{"id":6742,"date":"2026-02-10T09:21:20","date_gmt":"2026-02-10T01:21:20","guid":{"rendered":"https:\/\/feichuncables.com\/blog\/?p=6742"},"modified":"2026-02-10T09:21:24","modified_gmt":"2026-02-10T01:21:24","slug":"inductive-harvesting-how-does-the-magnetic-field-of-the-power-cores-induce-current-to-light-up-leds-without-physical-electrical-connection-2","status":"publish","type":"post","link":"https:\/\/feichuncables.com\/blog\/inductive-harvesting-how-does-the-magnetic-field-of-the-power-cores-induce-current-to-light-up-leds-without-physical-electrical-connection-2\/","title":{"rendered":"Inductive Harvesting: How Does the Magnetic Field of the Power Cores Induce Current to Light Up LEDs Without Physical Electrical Connection?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">An accessible technical explanation of how Faraday&#8217;s law of electromagnetic induction enables energy harvesting from the alternating magnetic field surrounding AC power conductors \u2014 and how that harvested energy can illuminate LEDs embedded in a mining cable&#8217;s sheath, with no galvanic connection to the power circuit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u7bc7\u901a\u4fd7\u7684\u6280\u672f\u89e3\u6790\uff1a\u6cd5\u62c9\u7b2c\u7535\u78c1\u611f\u5e94\u5b9a\u5f8b\u5982\u4f55\u4f7f\u4ea4\u6d41\u7535\u529b\u5bfc\u4f53\u5468\u56f4\u7684\u4ea4\u53d8\u78c1\u573a\u5b9e\u73b0\u80fd\u91cf\u6536\u96c6\u2014\u2014\u4ee5\u53ca\u8be5\u6536\u96c6\u7684\u80fd\u91cf\u5982\u4f55\u5728\u65e0\u4efb\u4f55\u7535\u6c14\u8fde\u63a5\u7684\u60c5\u51b5\u4e0b\u70b9\u4eae\u5d4c\u5165\u77ff\u7528\u7535\u7f06\u62a4\u5957\u4e2d\u7684LED\u706f\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-dominant-color=\"84250a\" data-has-transparency=\"false\" style=\"--dominant-color: #84250a;\" loading=\"lazy\" decoding=\"async\" width=\"310\" height=\"628\" sizes=\"auto, (max-width: 310px) 100vw, 310px\" src=\"https:\/\/feichuncables.com\/blog\/wp-content\/uploads\/image-795-310x628.avif\" alt=\"\" class=\"wp-image-6743 not-transparent\" title=\"\" srcset=\"https:\/\/feichuncables.com\/blog\/wp-content\/uploads\/image-795-310x628.avif 310w, https:\/\/feichuncables.com\/blog\/wp-content\/uploads\/image-795-148x300.avif 148w, https:\/\/feichuncables.com\/blog\/wp-content\/uploads\/image-795-400x809.avif 400w, https:\/\/feichuncables.com\/blog\/wp-content\/uploads\/image-795.avif 433w\" \/><\/figure>\n\n\n\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n<meta charset=\"UTF-8\">\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n<title>Inductive Harvesting: How Power-Core Magnetic Fields Light Up LEDs Without Wires | Feichun Cables<\/title>\n<meta name=\"description\" content=\"Technical deep-dive into electromagnetic induction energy harvesting inside mining cables. Learn how the magnetic field from AC power cores induces current in a receiver coil to illuminate LEDs without any physical electrical connection. Faraday's Law, Amp\u00e8re's Law, and practical cable engineering explained.\">\n<meta name=\"keywords\" content=\"inductive harvesting, electromagnetic induction, mining cable LED, self-luminous cable, Faraday law cable, magnetic field power core, wireless LED mining cable, TENAX-LUMEN, energy harvesting power line, Feichun cable\">\n<meta name=\"author\" content=\"Anhui Feichun Special Cable Co., Ltd.\">\n<link rel=\"canonical\" href=\"https:\/\/feichuncables.com\/blog\/inductive-harvesting-magnetic-field-led-mining-cable\/\">\n\n<!-- Fonts: Merriweather for editorial body, Source Code Pro for technical data -->\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Libre+Baskerville:ital,wght@0,400;0,700;1,400&#038;family=Source+Code+Pro:wght@400;500;600&#038;family=Noto+Sans+SC:wght@400;500;700&#038;display=swap\" rel=\"stylesheet\">\n\n<style>\n\/* ==========================================================================\n   CSS CUSTOM PROPERTIES \u2014 AUTOMATIC LIGHT \/ DARK MODE\n   Adapts to the host website's prefers-color-scheme setting.\n   No JavaScript. 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power cores generates a magnetic field that induces voltage in a small receiver coil to power LEDs without any wire connection.\",\n  \"datePublished\":\"2026-02-10\",\n  \"keywords\":\"inductive harvesting, electromagnetic induction, mining cable LED, Faraday's law, self-luminous cable\"\n}\n<\/script>\n<\/head>\n\n<body>\n\n<!-- ======================== HEADER ======================== -->\n<header class=\"site-hd\">\n<div class=\"wrap\">\n  <div class=\"site-hd-inner\">\n    <div>\n      <a href=\"https:\/\/feichuncables.com\" class=\"brand\" rel=\"nofollow noopener\" target=\"_blank\">Feichun Cables<\/a>\n      <span class=\"brand-cn\">\u5b89\u5fbd\u98de\u7eaf\u7279\u79cd\u7535\u7f06\u6709\u9650\u516c\u53f8<\/span>\n    <\/div>\n    <div class=\"hd-email\">\n      <a href=\"mailto:tech@feichuncables.com\" rel=\"nofollow noopener\">tech@feichuncables.com<\/a>\n    <\/div>\n  <\/div>\n<\/div>\n<\/header>\n\n<!-- ======================== BREADCRUMB ======================== -->\n<nav class=\"bc\" aria-label=\"Breadcrumb\">\n<div class=\"wrap\">\n  <a href=\"https:\/\/feichuncables.com\" rel=\"nofollow noopener\">Home<\/a><span>\/<\/span>\n  <a href=\"https:\/\/feichuncables.com\/blog\/\" rel=\"nofollow noopener\">Blog<\/a><span>\/<\/span>\n  Inductive Harvesting &amp; LED Illumination\n<\/div>\n<\/nav>\n\n<!-- ======================== ARTICLE ======================== -->\n<main class=\"wrap\">\n<article>\n\n  <!-- META -->\n  <div>\n    <div class=\"art-cat\">Electromagnetic Engineering &middot; \u7535\u78c1\u5de5\u7a0b<\/div>\n    <h1>Inductive Harvesting: How Does the Magnetic Field of the Power Cores Induce Current to Light Up LEDs Without Physical Electrical Connection?<\/h1>\n    <p class=\"sub\">An accessible technical explanation of how Faraday&#8217;s law of electromagnetic induction enables energy harvesting from the alternating magnetic field surrounding AC power conductors \u2014 and how that harvested energy can illuminate LEDs embedded in a mining cable&#8217;s sheath, with no galvanic connection to the power circuit.<\/p>\n    <p class=\"sub-cn\">\u4e00\u7bc7\u901a\u4fd7\u7684\u6280\u672f\u89e3\u6790\uff1a\u6cd5\u62c9\u7b2c\u7535\u78c1\u611f\u5e94\u5b9a\u5f8b\u5982\u4f55\u4f7f\u4ea4\u6d41\u7535\u529b\u5bfc\u4f53\u5468\u56f4\u7684\u4ea4\u53d8\u78c1\u573a\u5b9e\u73b0\u80fd\u91cf\u6536\u96c6\u2014\u2014\u4ee5\u53ca\u8be5\u6536\u96c6\u7684\u80fd\u91cf\u5982\u4f55\u5728\u65e0\u4efb\u4f55\u7535\u6c14\u8fde\u63a5\u7684\u60c5\u51b5\u4e0b\u70b9\u4eae\u5d4c\u5165\u77ff\u7528\u7535\u7f06\u62a4\u5957\u4e2d\u7684LED\u706f\u3002<\/p>\n    <div class=\"pub\">\n      <span>Published: February 2026<\/span>\n      <span>Author: Feichun R&amp;D Engineering<\/span>\n      <span>Reading: ~15 min<\/span>\n    <\/div>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a71 ========== -->\n  <h2>1. The Core Question<span class=\"cn\">\u6838\u5fc3\u95ee\u9898<\/span><\/h2>\n\n  <p>\n    Consider a medium-voltage mining trailing cable \u2014 for instance, an (N)TMCGEH3S rated 6\/10&nbsp;kV \u2014 carrying hundreds of amperes of alternating current through its three power cores to an electric rope shovel in an open-pit mine. Somewhere inside the same cable, a tiny LED glows steadily, making the cable visible to operators in darkness. Yet that LED has <strong>no wire, no contact, no physical electrical connection<\/strong> to the power cores. How is this possible?\n    <span class=\"cn\">\u8bbe\u60f3\u4e00\u6839\u4e2d\u538b\u77ff\u7528\u62d6\u62fd\u7535\u7f06\u2014\u2014\u4f8b\u5982\u989d\u5b9a 6\/10 kV \u7684 (N)TMCGEH3S\u2014\u2014\u901a\u8fc7\u4e09\u6839\u52a8\u529b\u7ebf\u82af\u5411\u9732\u5929\u77ff\u7684\u7535\u94f2\u8f93\u9001\u6570\u767e\u5b89\u57f9\u7684\u4ea4\u6d41\u7535\u3002\u5728\u540c\u4e00\u6839\u7535\u7f06\u5185\u90e8\u67d0\u5904\uff0c\u4e00\u9897\u5fae\u5c0f\u7684 LED \u7a33\u5b9a\u53d1\u5149\uff0c\u4f7f\u7535\u7f06\u5728\u9ed1\u6697\u4e2d\u5bf9\u64cd\u4f5c\u4eba\u5458\u53ef\u89c1\u3002\u4f46\u8be5 LED \u4e0e\u52a8\u529b\u7ebf\u82af\u4e4b\u95f4<strong>\u6ca1\u6709\u5bfc\u7ebf\u3001\u6ca1\u6709\u89e6\u70b9\u3001\u6ca1\u6709\u4efb\u4f55\u7269\u7406\u7535\u6c14\u8fde\u63a5<\/strong>\u3002\u8fd9\u662f\u5982\u4f55\u505a\u5230\u7684\uff1f<\/span>\n  <\/p>\n\n  <p>\n    The answer lies in one of the most fundamental and elegant principles in all of physics: <strong>electromagnetic induction<\/strong>, first discovered by Michael Faraday in 1831. Every AC power conductor generates a time-varying magnetic field in the space around it. If a small coil of wire \u2014 a &#8220;receiver&#8221; \u2014 is placed within that field, a voltage is induced across the coil, and if the coil is connected to an LED, current flows and the LED illuminates. No physical contact is needed. The energy is transferred through the magnetic field itself, across empty space, through insulation and rubber, as silently and invisibly as gravity.\n    <span class=\"cn\">\u7b54\u6848\u5728\u4e8e\u7269\u7406\u5b66\u4e2d\u6700\u57fa\u672c\u3001\u6700\u4f18\u7f8e\u7684\u539f\u7406\u4e4b\u4e00\uff1a<strong>\u7535\u78c1\u611f\u5e94<\/strong>\uff0c\u7531\u8fc8\u514b\u5c14\u00b7\u6cd5\u62c9\u7b2c\u4e8e1831\u5e74\u9996\u6b21\u53d1\u73b0\u3002\u6bcf\u6839\u4ea4\u6d41\u7535\u529b\u5bfc\u4f53\u90fd\u4f1a\u5728\u5176\u5468\u56f4\u7a7a\u95f4\u4ea7\u751f\u65f6\u53d8\u78c1\u573a\u3002\u5982\u679c\u5c06\u4e00\u4e2a\u5c0f\u7ebf\u5708\u2014\u2014\u5373&#8221;\u63a5\u6536\u5668&#8221;\u2014\u2014\u653e\u7f6e\u5728\u8be5\u78c1\u573a\u4e2d\uff0c\u7ebf\u5708\u4e24\u7aef\u5c06\u611f\u5e94\u51fa\u7535\u538b\uff1b\u5982\u679c\u7ebf\u5708\u8fde\u63a5 LED\uff0c\u7535\u6d41\u6d41\u8fc7\uff0cLED \u5373\u88ab\u70b9\u4eae\u3002\u65e0\u9700\u4efb\u4f55\u7269\u7406\u63a5\u89e6\u3002\u80fd\u91cf\u901a\u8fc7\u78c1\u573a\u672c\u8eab\u4f20\u9012\uff0c\u7a7f\u8d8a\u7a7a\u6c14\u3001\u7edd\u7f18\u5c42\u548c\u6a61\u80f6\uff0c\u5982\u540c\u5f15\u529b\u4e00\u822c\u65e0\u58f0\u65e0\u5f62\u3002<\/span>\n  <\/p>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a72 ========== -->\n  <h2>2. First Principles: Amp\u00e8re&#8217;s Law \u2014 The Magnetic Field Around a Conductor<span class=\"cn\">\u7b2c\u4e00\u6027\u539f\u7406\uff1a\u5b89\u57f9\u5b9a\u5f8b\u2014\u2014\u5bfc\u4f53\u5468\u56f4\u7684\u78c1\u573a<\/span><\/h2>\n\n  <p>\n    To understand inductive harvesting, we must begin at the very beginning: every current-carrying conductor produces a magnetic field. This is not an engineering approximation \u2014 it is a law of nature formalized by Andr\u00e9-Marie Amp\u00e8re in 1826 and incorporated into Maxwell&#8217;s equations. For a long, straight conductor carrying current <em>I<\/em>, the magnetic flux density <em>B<\/em> at a perpendicular distance <em>r<\/em> from the conductor is given by the following well-known relation.\n    <span class=\"cn\">\u8981\u7406\u89e3\u611f\u5e94\u80fd\u91cf\u6536\u96c6\uff0c\u5fc5\u987b\u4ece\u6700\u57fa\u672c\u7684\u539f\u7406\u5f00\u59cb\uff1a\u6bcf\u4e00\u6839\u8f7d\u6d41\u5bfc\u4f53\u90fd\u4f1a\u4ea7\u751f\u78c1\u573a\u3002\u8fd9\u4e0d\u662f\u5de5\u7a0b\u8fd1\u4f3c\u2014\u2014\u800c\u662f\u5b89\u5fb7\u70c8-\u739b\u4e3d\u00b7\u5b89\u57f9\u4e8e1826\u5e74\u5f62\u5f0f\u5316\u7684\u81ea\u7136\u6cd5\u5219\uff0c\u5e76\u88ab\u7eb3\u5165\u9ea6\u514b\u65af\u97e6\u65b9\u7a0b\u7ec4\u3002\u5bf9\u4e8e\u8f7d\u6709\u7535\u6d41 <em>I<\/em> \u7684\u957f\u76f4\u5bfc\u4f53\uff0c\u8ddd\u5bfc\u4f53\u5782\u76f4\u8ddd\u79bb <em>r<\/em> \u5904\u7684\u78c1\u901a\u5bc6\u5ea6 <em>B<\/em> \u7531\u4ee5\u4e0b\u8457\u540d\u5173\u7cfb\u5f0f\u7ed9\u51fa\u3002<\/span>\n  <\/p>\n\n  <div class=\"formula\">\n    <span class=\"label\">Amp\u00e8re&#8217;s Law \u2014 Field Outside a Conductor \u00b7 \u5b89\u57f9\u5b9a\u5f8b\u2014\u2014\u5bfc\u4f53\u5916\u90e8\u78c1\u573a<\/span>\n    B = \u03bc\u2080 \u00b7 I \/ (2\u03c0 \u00b7 r)<br><br>\n    Where:<br>\n    &nbsp;&nbsp;B = magnetic flux density (Tesla, T)<br>\n    &nbsp;&nbsp;\u03bc\u2080 = permeability of free space = 4\u03c0 \u00d7 10\u207b\u2077 H\/m<br>\n    &nbsp;&nbsp;I = current in the conductor (Amperes, A)<br>\n    &nbsp;&nbsp;r = radial distance from conductor center (meters, m)\n  <\/div>\n\n  <p>\n    This equation tells us several important things. First, the field is directly proportional to the current: the higher the current flowing in a mining cable&#8217;s power core (and mining cables routinely carry 200\u2013500&nbsp;A), the stronger the surrounding magnetic field. Second, the field decreases inversely with distance \u2014 but crucially, it does <em>not<\/em> vanish. Even at a distance of several centimeters (the typical spacing between a power core and the cable&#8217;s outer sheath), a measurable magnetic field persists. For example, at a current of 300&nbsp;A and a radial distance of 30&nbsp;mm (0.03&nbsp;m), the flux density is approximately 2&nbsp;mT \u2014 small by the standards of an MRI machine, but more than sufficient for energy harvesting.\n    <span class=\"cn\">\u8fd9\u4e2a\u65b9\u7a0b\u544a\u8bc9\u6211\u4eec\u51e0\u4e2a\u91cd\u8981\u4fe1\u606f\u3002\u9996\u5148\uff0c\u78c1\u573a\u4e0e\u7535\u6d41\u6210\u6b63\u6bd4\uff1a\u77ff\u7528\u7535\u7f06\u52a8\u529b\u82af\u7ebf\u4e2d\u6d41\u8fc7\u7684\u7535\u6d41\u8d8a\u5927\uff08\u77ff\u7528\u7535\u7f06\u901a\u5e38\u8f7d\u6709 200\u2013500 A\uff09\uff0c\u5468\u56f4\u78c1\u573a\u5c31\u8d8a\u5f3a\u3002\u5176\u6b21\uff0c\u78c1\u573a\u4e0e\u8ddd\u79bb\u6210\u53cd\u6bd4\u9012\u51cf\u2014\u2014\u4f46\u5173\u952e\u7684\u662f\uff0c\u5b83<em>\u5e76\u4e0d\u6d88\u5931<\/em>\u3002\u5373\u4f7f\u5728\u51e0\u5398\u7c73\u7684\u8ddd\u79bb\u5904\uff08\u52a8\u529b\u82af\u7ebf\u4e0e\u7535\u7f06\u5916\u62a4\u5957\u4e4b\u95f4\u7684\u5178\u578b\u95f4\u8ddd\uff09\uff0c\u4ecd\u7136\u5b58\u5728\u53ef\u6d4b\u91cf\u7684\u78c1\u573a\u3002\u4f8b\u5982\uff0c\u5728 300 A \u7535\u6d41\u548c 30 mm\uff080.03 m\uff09\u5f84\u5411\u8ddd\u79bb\u65f6\uff0c\u78c1\u901a\u5bc6\u5ea6\u7ea6\u4e3a 2 mT\u2014\u2014\u4ee5 MRI \u8bbe\u5907\u7684\u6807\u51c6\u6765\u770b\u5f88\u5c0f\uff0c\u4f46\u5bf9\u80fd\u91cf\u6536\u96c6\u800c\u8a00\u5df2\u7ef0\u7ef0\u6709\u4f59\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 1 \u2014 Calculated Magnetic Flux Density at Various Distances (I = 300 A, single conductor) \u00b7 \u88681 \u2014 \u4e0d\u540c\u8ddd\u79bb\u5904\u7684\u8ba1\u7b97\u78c1\u901a\u5bc6\u5ea6<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Distance r (mm)<\/th>\n          <th>Distance r (m)<\/th>\n          <th>B (mT)<\/th>\n          <th>B (\u03bcT)<\/th>\n          <th>Context<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr><td>10<\/td><td>0.010<\/td><td>6.00<\/td><td>6,000<\/td><td>Inside cable, adjacent to core insulation<td class=\"cn-cell\">\u7535\u7f06\u5185\u90e8\uff0c\u7d27\u90bb\u82af\u7ebf\u7edd\u7f18<\/td><\/td><\/tr>\n        <tr><td>20<\/td><td>0.020<\/td><td>3.00<\/td><td>3,000<\/td><td>Within cable fill area<\/td><\/tr>\n        <tr><td>30<\/td><td>0.030<\/td><td>2.00<\/td><td>2,000<\/td><td>Near outer sheath interior surface<td class=\"cn-cell\">\u63a5\u8fd1\u5916\u62a4\u5957\u5185\u8868\u9762<\/td><\/td><\/tr>\n        <tr><td>50<\/td><td>0.050<\/td><td>1.20<\/td><td>1,200<\/td><td>At outer sheath surface (typical cable OD ~100 mm)<\/td><\/tr>\n        <tr><td>100<\/td><td>0.100<\/td><td>0.60<\/td><td>600<\/td><td>Near cable surface, air gap<\/td><\/tr>\n        <tr><td>500<\/td><td>0.500<\/td><td>0.12<\/td><td>120<\/td><td>Half-meter from cable<\/td><\/tr>\n        <tr><td>1,000<\/td><td>1.000<\/td><td>0.06<\/td><td>60<\/td><td>One meter from cable<td class=\"cn-cell\">\u8ddd\u7535\u7f061\u7c73<\/td><\/td><\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <p>\n    <em>Note:<\/em> The values above assume a single isolated conductor. In a real three-phase cable, the magnetic fields from three cores partially cancel each other outside the cable (because the three phase currents sum to zero in a balanced system). However, within the cable&#8217;s interior \u2014 where the receiver coil is positioned \u2014 the local field from the nearest core dominates, and significant net flux density remains available for harvesting.\n    <span class=\"cn\"><em>\u6ce8\u610f\uff1a<\/em>\u4ee5\u4e0a\u6570\u503c\u5047\u8bbe\u4e3a\u5355\u6839\u9694\u79bb\u5bfc\u4f53\u3002\u5728\u5b9e\u9645\u4e09\u76f8\u7535\u7f06\u4e2d\uff0c\u4e09\u6839\u82af\u7ebf\u7684\u78c1\u573a\u5728\u7535\u7f06\u5916\u90e8\u4f1a\u90e8\u5206\u76f8\u4e92\u62b5\u6d88\uff08\u56e0\u4e3a\u5e73\u8861\u7cfb\u7edf\u4e2d\u4e09\u76f8\u7535\u6d41\u4e4b\u548c\u4e3a\u96f6\uff09\u3002\u7136\u800c\uff0c\u5728\u7535\u7f06\u5185\u90e8\u2014\u2014\u5373\u63a5\u6536\u7ebf\u5708\u6240\u5728\u4f4d\u7f6e\u2014\u2014\u6700\u8fd1\u82af\u7ebf\u7684\u5c40\u90e8\u78c1\u573a\u5360\u4e3b\u5bfc\u5730\u4f4d\uff0c\u4ecd\u6709\u663e\u8457\u7684\u51c0\u78c1\u901a\u5bc6\u5ea6\u53ef\u4f9b\u6536\u96c6\u3002<\/span>\n  <\/p>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a73 ========== -->\n  <h2>3. Faraday&#8217;s Law of Induction \u2014 From Magnetic Field to Voltage<span class=\"cn\">\u6cd5\u62c9\u7b2c\u611f\u5e94\u5b9a\u5f8b\u2014\u2014\u4ece\u78c1\u573a\u5230\u7535\u538b<\/span><\/h2>\n\n  <p>\n    Having established that a strong, time-varying magnetic field exists around the power cores, the next step is to convert that field into electrical energy. This is precisely the function of <strong>Faraday&#8217;s law of electromagnetic induction<\/strong>, which states that a changing magnetic flux through a closed loop of wire induces an electromotive force (EMF) \u2014 effectively, a voltage \u2014 in that loop. Mathematically, for a coil of <em>N<\/em> turns with a changing magnetic flux \u03a6 through each turn, the induced EMF is expressed as follows.\n    <span class=\"cn\">\u5df2\u7ecf\u786e\u5b9a\u4e86\u52a8\u529b\u82af\u7ebf\u5468\u56f4\u5b58\u5728\u5f3a\u65f6\u53d8\u78c1\u573a\u540e\uff0c\u4e0b\u4e00\u6b65\u662f\u5c06\u8be5\u78c1\u573a\u8f6c\u6362\u4e3a\u7535\u80fd\u3002\u8fd9\u6b63\u662f<strong>\u6cd5\u62c9\u7b2c\u7535\u78c1\u611f\u5e94\u5b9a\u5f8b<\/strong>\u7684\u529f\u80fd\uff0c\u8be5\u5b9a\u5f8b\u6307\u51fa\uff1a\u7a7f\u8fc7\u95ed\u5408\u7ebf\u5708\u7684\u53d8\u5316\u78c1\u901a\u4f1a\u5728\u8be5\u7ebf\u5708\u4e2d\u611f\u5e94\u51fa\u7535\u52a8\u52bf\uff08EMF\uff09\u2014\u2014\u5373\u7535\u538b\u3002\u5bf9\u4e8e\u5177\u6709 <em>N<\/em> \u531d\u4e14\u6bcf\u531d\u78c1\u901a \u03a6 \u53d8\u5316\u7684\u7ebf\u5708\uff0c\u611f\u5e94\u7535\u52a8\u52bf\u7684\u6570\u5b66\u8868\u8fbe\u5982\u4e0b\u3002<\/span>\n  <\/p>\n\n  <div class=\"formula\">\n    <span class=\"label\">Faraday&#8217;s Law of Induction \u00b7 \u6cd5\u62c9\u7b2c\u611f\u5e94\u5b9a\u5f8b<\/span>\n    EMF = \u2212N \u00b7 d\u03a6\/dt<br><br>\n    Where:<br>\n    &nbsp;&nbsp;EMF = induced electromotive force (Volts, V)<br>\n    &nbsp;&nbsp;N = number of turns in the receiver coil<br>\n    &nbsp;&nbsp;\u03a6 = magnetic flux through each turn (Weber, Wb) = B \u00b7 A \u00b7 cos(\u03b8)<br>\n    &nbsp;&nbsp;d\u03a6\/dt = rate of change of magnetic flux with time<br>\n    &nbsp;&nbsp;A = cross-sectional area of each coil turn (m\u00b2)<br>\n    &nbsp;&nbsp;\u03b8 = angle between the magnetic field and the coil&#8217;s normal axis\n  <\/div>\n\n  <p>\n    The negative sign reflects <strong>Lenz&#8217;s law<\/strong>: the induced current flows in a direction that opposes the change in flux that produced it \u2014 a direct consequence of the conservation of energy. The critical insight here is the <em>rate of change<\/em> requirement. A <em>static<\/em> (DC) magnetic field produces zero induced EMF. But in an AC power cable operating at 50&nbsp;Hz (or 60&nbsp;Hz), the current \u2014 and therefore the magnetic field \u2014 reverses direction 100 times per second (120 times at 60&nbsp;Hz), ensuring a continuously changing flux and a continuously induced voltage in the receiver coil.\n    <span class=\"cn\">\u8d1f\u53f7\u53cd\u6620\u4e86<strong>\u695e\u6b21\u5b9a\u5f8b<\/strong>\uff1a\u611f\u5e94\u7535\u6d41\u7684\u65b9\u5411\u603b\u662f\u53cd\u5bf9\u4ea7\u751f\u5b83\u7684\u78c1\u901a\u53d8\u5316\u2014\u2014\u8fd9\u662f\u80fd\u91cf\u5b88\u6052\u7684\u76f4\u63a5\u7ed3\u679c\u3002\u8fd9\u91cc\u7684\u5173\u952e\u6d1e\u5bdf\u662f<em>\u53d8\u5316\u7387<\/em>\u7684\u8981\u6c42\u3002<em>\u9759\u6001<\/em>\uff08\u76f4\u6d41\uff09\u78c1\u573a\u4ea7\u751f\u7684\u611f\u5e94\u7535\u52a8\u52bf\u4e3a\u96f6\u3002\u4f46\u5728\u5de5\u4f5c\u9891\u7387\u4e3a 50 Hz\uff08\u6216 60 Hz\uff09\u7684\u4ea4\u6d41\u7535\u529b\u7535\u7f06\u4e2d\uff0c\u7535\u6d41\u2014\u2014\u56e0\u800c\u78c1\u573a\u2014\u2014\u6bcf\u79d2\u53cd\u8f6c 100 \u6b21\uff0860 Hz \u65f6\u4e3a 120 \u6b21\uff09\uff0c\u786e\u4fdd\u63a5\u6536\u7ebf\u5708\u4e2d\u6301\u7eed\u53d8\u5316\u7684\u78c1\u901a\u548c\u6301\u7eed\u611f\u5e94\u7684\u7535\u538b\u3002<\/span>\n  <\/p>\n\n  <div class=\"callout callout-blue\">\n    <div class=\"callout-title\">Key Insight \u00b7 \u5173\u952e\u8ba4\u8bc6<\/div>\n    <p style=\"margin-bottom:0;\">\n      The entire mechanism is identical in principle to how a <strong>transformer<\/strong> works. In a transformer, the primary winding generates a time-varying magnetic flux in a shared iron core, and the secondary winding picks up that flux to produce an output voltage. In inductive harvesting within a cable, the power core acts as a single-turn &#8220;primary,&#8221; the space inside the cable serves as an air-core flux path, and the small receiver coil serves as a &#8220;secondary.&#8221; There is no iron core \u2014 coupling is weaker, so only milliwatts of power are harvested \u2014 but the underlying physics is exactly the same: Faraday&#8217;s law.\n      <span class=\"cn\">\u6574\u4e2a\u673a\u5236\u5728\u539f\u7406\u4e0a\u4e0e<strong>\u53d8\u538b\u5668<\/strong>\u5b8c\u5168\u76f8\u540c\u3002\u5728\u53d8\u538b\u5668\u4e2d\uff0c\u521d\u7ea7\u7ed5\u7ec4\u5728\u5171\u4eab\u94c1\u82af\u4e2d\u4ea7\u751f\u65f6\u53d8\u78c1\u901a\uff0c\u6b21\u7ea7\u7ed5\u7ec4\u62fe\u53d6\u8be5\u78c1\u901a\u4ee5\u4ea7\u751f\u8f93\u51fa\u7535\u538b\u3002\u5728\u7535\u7f06\u5185\u90e8\u7684\u611f\u5e94\u80fd\u91cf\u6536\u96c6\u4e2d\uff0c\u52a8\u529b\u82af\u7ebf\u5145\u5f53\u5355\u531d&#8221;\u521d\u7ea7&#8221;\uff0c\u7535\u7f06\u5185\u90e8\u7a7a\u95f4\u5145\u5f53\u7a7a\u5fc3\u78c1\u901a\u8def\u5f84\uff0c\u5c0f\u63a5\u6536\u7ebf\u5708\u5145\u5f53&#8221;\u6b21\u7ea7&#8221;\u3002\u6ca1\u6709\u94c1\u82af\u2014\u2014\u8026\u5408\u8f83\u5f31\uff0c\u56e0\u6b64\u4ec5\u6536\u96c6\u6beb\u74e6\u7ea7\u529f\u7387\u2014\u2014\u4f46\u57fa\u672c\u7269\u7406\u539f\u7406\u5b8c\u5168\u76f8\u540c\uff1a\u6cd5\u62c9\u7b2c\u5b9a\u5f8b\u3002<\/span>\n    <\/p>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a74 ========== -->\n  <h2>4. The Receiver Coil \u2014 A Miniature Energy Harvester<span class=\"cn\">\u63a5\u6536\u7ebf\u5708\u2014\u2014\u5fae\u578b\u80fd\u91cf\u6536\u96c6\u5668<\/span><\/h2>\n\n  <p>\n    To capture enough energy from the ambient magnetic field to illuminate an LED, a small receiver coil is designed with several parameters tuned for maximum energy extraction. The key design variables are the number of turns (<em>N<\/em>), the coil area (<em>A<\/em>), the coil&#8217;s orientation relative to the magnetic field, and whether a ferrite core is used to concentrate flux. The table below summarizes how each parameter affects the harvested voltage.\n    <span class=\"cn\">\u4e3a\u4e86\u4ece\u73af\u5883\u78c1\u573a\u4e2d\u6355\u83b7\u8db3\u591f\u7684\u80fd\u91cf\u6765\u70b9\u4eae LED\uff0c\u9700\u8981\u8bbe\u8ba1\u4e00\u4e2a\u5c0f\u578b\u63a5\u6536\u7ebf\u5708\uff0c\u5176\u591a\u4e2a\u53c2\u6570\u7ecf\u8fc7\u8c03\u4f18\u4ee5\u5b9e\u73b0\u6700\u5927\u80fd\u91cf\u63d0\u53d6\u3002\u5173\u952e\u8bbe\u8ba1\u53d8\u91cf\u5305\u62ec\u531d\u6570\uff08<em>N<\/em>\uff09\u3001\u7ebf\u5708\u9762\u79ef\uff08<em>A<\/em>\uff09\u3001\u7ebf\u5708\u76f8\u5bf9\u4e8e\u78c1\u573a\u7684\u65b9\u5411\uff0c\u4ee5\u53ca\u662f\u5426\u4f7f\u7528\u94c1\u6c27\u4f53\u78c1\u82af\u6765\u96c6\u4e2d\u78c1\u901a\u3002\u4e0b\u8868\u603b\u7ed3\u4e86\u5404\u53c2\u6570\u5bf9\u6536\u96c6\u7535\u538b\u7684\u5f71\u54cd\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 2 \u2014 Receiver Coil Design Parameters and Their Effects \u00b7 \u88682 \u2014 \u63a5\u6536\u7ebf\u5708\u8bbe\u8ba1\u53c2\u6570\u53ca\u5176\u5f71\u54cd<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Parameter<\/th>\n          <th>Symbol<\/th>\n          <th>Effect on Induced EMF<\/th>\n          <th>Practical Consideration<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr>\n          <td>Number of turns<td class=\"cn-cell\">\u531d\u6570<\/td><\/td>\n          <td><em>N<\/em><\/td>\n          <td>EMF \u221d N (linear increase)<\/td>\n          <td>More turns = higher voltage but increased coil resistance, size, and weight<\/td>\n        <\/tr>\n        <tr>\n          <td>Coil cross-sectional area<td class=\"cn-cell\">\u7ebf\u5708\u622a\u9762\u79ef<\/td><\/td>\n          <td><em>A<\/em><\/td>\n          <td>EMF \u221d A (linear increase)<\/td>\n          <td>Larger area captures more flux, but must fit within cable geometry \u2014 typically limited to a few cm\u00b2<\/td>\n        <\/tr>\n        <tr>\n          <td>Magnetic flux density<td class=\"cn-cell\">\u78c1\u901a\u5bc6\u5ea6<\/td><\/td>\n          <td><em>B<\/em><\/td>\n          <td>EMF \u221d B (linear increase)<\/td>\n          <td>Determined by load current in power cores and distance \u2014 not a designer&#8217;s free variable<\/td>\n        <\/tr>\n        <tr>\n          <td>Frequency of AC field<td class=\"cn-cell\">\u4ea4\u6d41\u78c1\u573a\u9891\u7387<\/td><\/td>\n          <td><em>f<\/em><\/td>\n          <td>EMF \u221d f (linear increase)<\/td>\n          <td>Fixed by power-system frequency: 50 Hz (most of world) or 60 Hz (Americas, parts of Asia)<\/td>\n        <\/tr>\n        <tr>\n          <td>Coil orientation angle<td class=\"cn-cell\">\u7ebf\u5708\u65b9\u5411\u89d2<\/td><\/td>\n          <td><em>\u03b8<\/em><\/td>\n          <td>EMF \u221d cos(\u03b8); maximum at \u03b8 = 0\u00b0<\/td>\n          <td>Coil axis should align with magnetic field direction (perpendicular to power core) for maximum coupling<\/td>\n        <\/tr>\n        <tr>\n          <td>Ferrite core<td class=\"cn-cell\">\u94c1\u6c27\u4f53\u78c1\u82af<\/td><\/td>\n          <td>\u03bc<sub>r<\/sub><\/td>\n          <td>EMF \u221d \u03bc<sub>eff<\/sub> (effective permeability); can multiply flux by 10\u00d7\u2013100\u00d7<\/td>\n          <td>A small ferrite rod or toroid dramatically concentrates flux lines, boosting harvested power<\/td>\n        <\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <p>\n    For a sinusoidal AC current at frequency <em>f<\/em>, the magnetic flux varies as \u03a6(t) = B<sub>peak<\/sub> \u00b7 A \u00b7 sin(2\u03c0ft), and the peak induced EMF simplifies to the following expression.\n    <span class=\"cn\">\u5bf9\u4e8e\u9891\u7387\u4e3a <em>f<\/em> \u7684\u6b63\u5f26\u4ea4\u6d41\u7535\u6d41\uff0c\u78c1\u901a\u6309 \u03a6(t) = B<sub>peak<\/sub> \u00b7 A \u00b7 sin(2\u03c0ft) \u53d8\u5316\uff0c\u611f\u5e94\u7535\u52a8\u52bf\u7684\u5cf0\u503c\u7b80\u5316\u4e3a\u4ee5\u4e0b\u8868\u8fbe\u5f0f\u3002<\/span>\n  <\/p>\n\n  <div class=\"formula\">\n    <span class=\"label\">Peak Induced EMF (sinusoidal AC) \u00b7 \u5cf0\u503c\u611f\u5e94\u7535\u52a8\u52bf\uff08\u6b63\u5f26\u4ea4\u6d41\uff09<\/span>\n    EMF<sub>peak<\/sub> = N \u00b7 B<sub>peak<\/sub> \u00b7 A \u00b7 2\u03c0 \u00b7 f<br><br>\n    Numerical example (50 Hz, mining cable):<br>\n    &nbsp;&nbsp;N = 200 turns, B<sub>peak<\/sub> = 2 mT = 2 \u00d7 10\u207b\u00b3 T,<br>\n    &nbsp;&nbsp;A = 3 cm\u00b2 = 3 \u00d7 10\u207b\u2074 m\u00b2, f = 50 Hz<br><br>\n    &nbsp;&nbsp;EMF<sub>peak<\/sub> = 200 \u00d7 2\u00d710\u207b\u00b3 \u00d7 3\u00d710\u207b\u2074 \u00d7 2\u03c0 \u00d7 50<br>\n    &nbsp;&nbsp;EMF<sub>peak<\/sub> \u2248 200 \u00d7 2\u00d710\u207b\u00b3 \u00d7 3\u00d710\u207b\u2074 \u00d7 314.16<br>\n    &nbsp;&nbsp;EMF<sub>peak<\/sub> \u2248 <strong>37.7 mV<\/strong>\n  <\/div>\n\n  <p>\n    At first glance, 37.7&nbsp;mV seems too low \u2014 a typical red LED requires a forward voltage of about 1.8&nbsp;V. But this is where circuit engineering comes in. With a ferrite core concentrating flux by a factor of 50\u2013100\u00d7, and with additional turns or a resonant LC circuit tuned to 50&nbsp;Hz to boost the voltage, the induced EMF can readily be elevated to several volts \u2014 more than sufficient to forward-bias an LED.\n    <span class=\"cn\">\u4e4d\u4e00\u770b\uff0c37.7 mV \u4f3c\u4e4e\u592a\u4f4e\u2014\u2014\u5178\u578b\u7ea2\u8272 LED \u9700\u8981\u7ea6 1.8 V \u7684\u6b63\u5411\u7535\u538b\u3002\u4f46\u8fd9\u6b63\u662f\u7535\u8def\u5de5\u7a0b\u7684\u7528\u6b66\u4e4b\u5730\u3002\u5229\u7528\u94c1\u6c27\u4f53\u78c1\u82af\u5c06\u78c1\u901a\u96c6\u4e2d 50\u2013100 \u500d\uff0c\u52a0\u4e0a\u589e\u52a0\u531d\u6570\u6216\u91c7\u7528\u8c10\u632f\u4e8e 50 Hz \u7684 LC \u7535\u8def\u6765\u63d0\u5347\u7535\u538b\uff0c\u611f\u5e94\u7535\u52a8\u52bf\u53ef\u8f7b\u677e\u63d0\u5347\u81f3\u6570\u4f0f\u7279\u2014\u2014\u8db3\u4ee5\u4f7f LED \u6b63\u5411\u5bfc\u901a\u3002<\/span>\n  <\/p>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a75 ========== -->\n  <h2>5. The Complete Energy Harvesting Circuit<span class=\"cn\">\u5b8c\u6574\u7684\u80fd\u91cf\u6536\u96c6\u7535\u8def<\/span><\/h2>\n\n  <p>\n    Between the receiver coil and the LED, a small conditioning circuit converts the raw AC induced voltage into a usable DC supply. The circuit is simple, robust, and requires no active power supply of its own \u2014 it runs entirely on harvested energy. The typical topology consists of three stages arranged in a chain.\n    <span class=\"cn\">\u5728\u63a5\u6536\u7ebf\u5708\u548c LED \u4e4b\u95f4\uff0c\u4e00\u4e2a\u5c0f\u578b\u8c03\u7406\u7535\u8def\u5c06\u539f\u59cb\u4ea4\u6d41\u611f\u5e94\u7535\u538b\u8f6c\u6362\u4e3a\u53ef\u7528\u7684\u76f4\u6d41\u7535\u6e90\u3002\u8be5\u7535\u8def\u7b80\u5355\u3001\u53ef\u9760\uff0c\u4e0d\u9700\u8981\u81ea\u8eab\u7684\u6709\u6e90\u7535\u6e90\u2014\u2014\u5b8c\u5168\u4f9d\u9760\u6536\u96c6\u7684\u80fd\u91cf\u8fd0\u884c\u3002\u5178\u578b\u62d3\u6251\u7531\u4e09\u4e2a\u4f9d\u6b21\u6392\u5217\u7684\u7ea7\u7ec4\u6210\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 3 \u2014 Energy Harvesting Circuit Stages \u00b7 \u88683 \u2014 \u80fd\u91cf\u6536\u96c6\u7535\u8def\u5404\u7ea7<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Stage<\/th>\n          <th>Function<\/th>\n          <th>Typical Components<\/th>\n          <th>\u529f\u80fd\u8bf4\u660e<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr>\n          <td><strong>1. Resonant Tuning<\/strong><\/td>\n          <td>A capacitor <em>C<\/em> is connected in parallel (or series) with the receiver coil&#8217;s inductance <em>L<\/em> to form an LC resonant circuit tuned to 50\/60&nbsp;Hz. At resonance, the impedance is minimized and the voltage across the coil is amplified by the quality factor <em>Q<\/em>.<\/td>\n          <td>Capacitor (typically 1\u2013100&nbsp;\u03bcF film cap)<\/td>\n          <td class=\"cn-cell\">\u7535\u5bb9 C \u4e0e\u63a5\u6536\u7ebf\u5708\u7535\u611f L \u5e76\u8054\uff08\u6216\u4e32\u8054\uff09\u5f62\u6210\u8c10\u632f\u4e8e 50\/60 Hz \u7684 LC \u7535\u8def\u3002\u5728\u8c10\u632f\u65f6\u963b\u6297\u6700\u5c0f\uff0c\u7ebf\u5708\u7535\u538b\u88ab\u54c1\u8d28\u56e0\u6570 Q \u653e\u5927\u3002<\/td>\n        <\/tr>\n        <tr>\n          <td><strong>2. Rectification<\/strong><\/td>\n          <td>The amplified AC voltage is converted to pulsating DC using a diode bridge or a voltage-doubler rectifier. Low-forward-voltage Schottky or germanium diodes are preferred to minimize voltage loss across the diode junction.<\/td>\n          <td>Schottky diode bridge (e.g., BAT54S) or 1N5817<\/td>\n          <td class=\"cn-cell\">\u653e\u5927\u540e\u7684\u4ea4\u6d41\u7535\u538b\u901a\u8fc7\u4e8c\u6781\u7ba1\u6865\u5f0f\u6216\u500d\u538b\u6574\u6d41\u7535\u8def\u8f6c\u6362\u4e3a\u8109\u52a8\u76f4\u6d41\u3002\u4f18\u9009\u4f4e\u6b63\u5411\u538b\u964d\u7684\u8096\u7279\u57fa\u6216\u9517\u4e8c\u6781\u7ba1\u4ee5\u51cf\u5c11\u7ed3\u538b\u964d\u635f\u8017\u3002<\/td>\n        <\/tr>\n        <tr>\n          <td><strong>3. Smoothing &amp; LED Drive<\/strong><\/td>\n          <td>A small reservoir capacitor smooths the pulsating DC. A current-limiting resistor (or a simple LDO if power budget permits) feeds the LED at the correct forward current, typically 1\u201320&nbsp;mA.<\/td>\n          <td>Electrolytic cap (10\u2013100&nbsp;\u03bcF), series resistor, LED<\/td>\n          <td class=\"cn-cell\">\u5c0f\u578b\u50a8\u80fd\u7535\u5bb9\u5e73\u6ed1\u8109\u52a8\u76f4\u6d41\u3002\u9650\u6d41\u7535\u963b\uff08\u6216\u4f4e\u538b\u5dee\u7a33\u538b\u5668\uff09\u4ee5\u6b63\u786e\u7684\u6b63\u5411\u7535\u6d41\uff08\u901a\u5e38 1\u201320 mA\uff09\u9a71\u52a8 LED\u3002<\/td>\n        <\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <div class=\"callout callout-green\">\n    <div class=\"callout-title\">The Resonance Advantage \u00b7 \u8c10\u632f\u4f18\u52bf<\/div>\n    <p style=\"margin-bottom:0;\">\n      The resonant LC circuit is the single most important element in making inductive harvesting practical at power-line frequencies. At resonance, the voltage across the coil can be amplified by a factor of <em>Q<\/em> (the quality factor), where <em>Q<\/em> = (1\/R)\u00b7\u221a(L\/C). For a well-wound coil on a ferrite core, <em>Q<\/em> values of 20\u201360 are achievable at 50&nbsp;Hz, meaning the effective voltage is multiplied 20\u201360\u00d7 compared to the un-tuned case. This is how a raw induced EMF of tens of millivolts becomes several volts \u2014 enough to drive one or more LEDs.\n      <span class=\"cn\">\u8c10\u632f LC \u7535\u8def\u662f\u4f7f\u611f\u5e94\u80fd\u91cf\u6536\u96c6\u5728\u5de5\u9891\u4e0b\u53d8\u5f97\u53ef\u884c\u7684\u6700\u5173\u952e\u5143\u4ef6\u3002\u5728\u8c10\u632f\u65f6\uff0c\u7ebf\u5708\u4e0a\u7684\u7535\u538b\u53ef\u88ab\u54c1\u8d28\u56e0\u6570 <em>Q<\/em> \u653e\u5927\uff0c\u5176\u4e2d <em>Q<\/em> = (1\/R)\u00b7\u221a(L\/C)\u3002\u5bf9\u4e8e\u94c1\u6c27\u4f53\u78c1\u82af\u4e0a\u7cbe\u5fc3\u7ed1\u624e\u7684\u7ebf\u5708\uff0c\u5728 50 Hz \u4e0b <em>Q<\/em> \u503c\u53ef\u8fbe 20\u201360\uff0c\u5373\u6709\u6548\u7535\u538b\u6bd4\u672a\u8c03\u8c10\u60c5\u51b5\u653e\u5927 20\u201360 \u500d\u3002\u8fd9\u5c31\u662f\u539f\u59cb\u611f\u5e94\u7535\u52a8\u52bf\u4ece\u6570\u5341\u6beb\u4f0f\u53d8\u4e3a\u6570\u4f0f\u7279\u7684\u539f\u56e0\u2014\u2014\u8db3\u4ee5\u9a71\u52a8\u4e00\u4e2a\u6216\u591a\u4e2a LED\u3002<\/span>\n    <\/p>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a76 ========== -->\n  <h2>6. Why AC Makes This Possible \u2014 And DC Does Not<span class=\"cn\">\u4e3a\u4ec0\u4e48\u4ea4\u6d41\u7535\u4f7f\u8fd9\u6210\u4e3a\u53ef\u80fd\u2014\u2014\u800c\u76f4\u6d41\u7535\u4e0d\u884c<\/span><\/h2>\n\n  <p>\n    A frequently asked question is: would this work with a DC cable? The short answer is <strong>no<\/strong>. Faraday&#8217;s law requires a <em>changing<\/em> magnetic flux \u2014 d\u03a6\/dt must be non-zero. A DC current produces a constant, static magnetic field. A static field passing through a coil produces zero rate of change and therefore zero induced EMF. The coil would simply sit in a steady magnetic field and generate nothing.\n    <span class=\"cn\">\u4e00\u4e2a\u5e38\u88ab\u95ee\u5230\u7684\u95ee\u9898\u662f\uff1a\u76f4\u6d41\u7535\u7f06\u53ef\u4ee5\u5417\uff1f\u7b80\u77ed\u7684\u56de\u7b54\u662f<strong>\u4e0d\u884c<\/strong>\u3002\u6cd5\u62c9\u7b2c\u5b9a\u5f8b\u8981\u6c42<em>\u53d8\u5316\u7684<\/em>\u78c1\u901a\u2014\u2014d\u03a6\/dt \u5fc5\u987b\u975e\u96f6\u3002\u76f4\u6d41\u7535\u6d41\u4ea7\u751f\u6052\u5b9a\u4e0d\u53d8\u7684\u9759\u6001\u78c1\u573a\u3002\u9759\u6001\u78c1\u573a\u7a7f\u8fc7\u7ebf\u5708\u65f6\u53d8\u5316\u7387\u4e3a\u96f6\uff0c\u56e0\u6b64\u611f\u5e94\u7535\u52a8\u52bf\u4e3a\u96f6\u3002\u7ebf\u5708\u53ea\u4f1a\u5904\u4e8e\u7a33\u6001\u78c1\u573a\u4e2d\uff0c\u4ec0\u4e48\u4e5f\u4e0d\u4f1a\u4ea7\u751f\u3002<\/span>\n  <\/p>\n\n  <p>\n    This is why the technology is inherently tied to <strong>AC power systems<\/strong> \u2014 and conveniently, virtually all mining electrical distribution operates on AC at 50 or 60&nbsp;Hz. The frequency also matters: higher frequency means faster flux change and therefore higher induced EMF (EMF&nbsp;\u221d&nbsp;f). This is why some advanced energy-harvesting research explores higher harmonic components present in real-world power cables, which can contribute additional harvestable energy beyond the fundamental 50\/60&nbsp;Hz component.\n    <span class=\"cn\">\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u8be5\u6280\u672f\u4e0e<strong>\u4ea4\u6d41\u7535\u529b\u7cfb\u7edf<\/strong>\u5929\u7136\u7ed1\u5b9a\u2014\u2014\u800c\u65b9\u4fbf\u7684\u662f\uff0c\u51e0\u4e4e\u6240\u6709\u77ff\u5c71\u914d\u7535\u7cfb\u7edf\u90fd\u4ee5 50 \u6216 60 Hz \u7684\u4ea4\u6d41\u8fd0\u884c\u3002\u9891\u7387\u4e5f\u5f88\u91cd\u8981\uff1a\u66f4\u9ad8\u7684\u9891\u7387\u610f\u5473\u7740\u66f4\u5feb\u7684\u78c1\u901a\u53d8\u5316\uff0c\u56e0\u6b64\u611f\u5e94\u7535\u52a8\u52bf\u66f4\u9ad8\uff08EMF \u221d f\uff09\u3002\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u4e00\u4e9b\u5148\u8fdb\u7684\u80fd\u91cf\u6536\u96c6\u7814\u7a76\u63a2\u7d22\u5b9e\u9645\u7535\u529b\u7535\u7f06\u4e2d\u5b58\u5728\u7684\u9ad8\u6b21\u8c10\u6ce2\u5206\u91cf\uff0c\u8fd9\u4e9b\u5206\u91cf\u53ef\u4ee5\u5728\u57fa\u6ce2 50\/60 Hz \u5206\u91cf\u4e4b\u5916\u8d21\u732e\u989d\u5916\u7684\u53ef\u6536\u96c6\u80fd\u91cf\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 4 \u2014 AC vs. DC: Why Inductive Harvesting Requires Alternating Current \u00b7 \u88684 \u2014 \u4ea4\u6d41\u4e0e\u76f4\u6d41\u5bf9\u6bd4<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Characteristic<\/th>\n          <th>AC Power Cable<\/th>\n          <th>DC Power Cable<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr><td>Magnetic field type<td class=\"cn-cell\">\u78c1\u573a\u7c7b\u578b<\/td><\/td><td>Time-varying (sinusoidal at 50\/60 Hz)<\/td><td>Static (constant in time)<\/td><\/tr>\n        <tr><td>d\u03a6\/dt<\/td><td>Non-zero, continuously oscillating<\/td><td>Zero (no change)<\/td><\/tr>\n        <tr><td>Induced EMF in receiver coil<td class=\"cn-cell\">\u63a5\u6536\u7ebf\u5708\u4e2d\u7684\u611f\u5e94EMF<\/td><\/td><td>Continuously generated (AC voltage)<\/td><td>None \u2014 zero voltage<\/td><\/tr>\n        <tr><td>Energy harvesting possible?<td class=\"cn-cell\">\u80fd\u5426\u8fdb\u884c\u80fd\u91cf\u6536\u96c6\uff1f<\/td><\/td><td><strong>Yes<\/strong><\/td><td><strong>No<\/strong><\/td><\/tr>\n        <tr><td>Transformer analogy<\/td><td>Functions as air-core transformer<\/td><td>No transformer action possible<\/td><\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a77 ========== -->\n  <h2>7. Three-Phase Cables: Magnetic Field Behavior<span class=\"cn\">\u4e09\u76f8\u7535\u7f06\uff1a\u78c1\u573a\u884c\u4e3a<\/span><\/h2>\n\n  <p>\n    Real mining trailing cables carry three-phase AC power, with currents in the three cores phase-shifted by 120\u00b0. In a perfectly balanced system, the vector sum of the three currents is zero at every instant, which means their magnetic fields partially cancel when observed at points well outside the cable. This is desirable for electromagnetic compatibility and human exposure limits (the ICNIRP recommends a general-public exposure limit of 100&nbsp;\u03bcT at 50&nbsp;Hz). However, inside the cable, the geometry is different.\n    <span class=\"cn\">\u771f\u5b9e\u7684\u77ff\u7528\u62d6\u62fd\u7535\u7f06\u627f\u8f7d\u4e09\u76f8\u4ea4\u6d41\u7535\u529b\uff0c\u4e09\u6839\u82af\u7ebf\u4e2d\u7684\u7535\u6d41\u76f8\u4f4d\u5dee\u4e3a 120\u00b0\u3002\u5728\u5b8c\u5168\u5e73\u8861\u7684\u7cfb\u7edf\u4e2d\uff0c\u4e09\u4e2a\u7535\u6d41\u7684\u77e2\u91cf\u548c\u5728\u6bcf\u4e00\u65f6\u523b\u5747\u4e3a\u96f6\uff0c\u8fd9\u610f\u5473\u7740\u5728\u7535\u7f06\u5916\u90e8\u8fdc\u5904\u89c2\u6d4b\u65f6\uff0c\u5176\u78c1\u573a\u4f1a\u90e8\u5206\u62b5\u6d88\u3002\u8fd9\u5bf9\u7535\u78c1\u517c\u5bb9\u6027\u548c\u4eba\u4f53\u66b4\u9732\u9650\u503c\u6709\u5229\uff08ICNIRP \u5efa\u8bae50 Hz\u65f6\u4e00\u822c\u516c\u4f17\u66b4\u9732\u9650\u503c\u4e3a 100 \u03bcT\uff09\u3002\u7136\u800c\u5728\u7535\u7f06\u5185\u90e8\uff0c\u51e0\u4f55\u5173\u7cfb\u4e0d\u540c\u3002<\/span>\n  <\/p>\n\n  <p>\n    When a small receiver coil is placed in the interstice (filler space) between the power cores, it is close enough to one core that the field from that core dominates. The partial cancellation from the other two cores \u2014 located farther away \u2014 only marginally reduces the local flux. Research using COMSOL Multiphysics finite-element simulation for a typical 12\/20&nbsp;kV three-phase underground cable has confirmed that the magnetic flux density within a cable&#8217;s cross-section, near individual cores, can range from 1 to 10&nbsp;mT depending on load current and geometry \u2014 values well within the practical range for inductive harvesting.\n    <span class=\"cn\">\u5f53\u5c0f\u578b\u63a5\u6536\u7ebf\u5708\u653e\u7f6e\u5728\u52a8\u529b\u82af\u7ebf\u4e4b\u95f4\u7684\u95f4\u9699\uff08\u586b\u5145\u7a7a\u95f4\uff09\u4e2d\u65f6\uff0c\u5b83\u8ddd\u79bb\u4e00\u6839\u82af\u7ebf\u8db3\u591f\u8fd1\uff0c\u4f7f\u5f97\u8be5\u82af\u7ebf\u7684\u78c1\u573a\u5360\u4e3b\u5bfc\u5730\u4f4d\u3002\u6765\u81ea\u5176\u4ed6\u4e24\u6839\u8f83\u8fdc\u82af\u7ebf\u7684\u90e8\u5206\u62b5\u6d88\u4ec5\u7565\u5fae\u964d\u4f4e\u4e86\u5c40\u90e8\u78c1\u901a\u3002\u4f7f\u7528 COMSOL Multiphysics \u6709\u9650\u5143\u4eff\u771f\u5bf9\u5178\u578b 12\/20 kV \u4e09\u76f8\u5730\u4e0b\u7535\u7f06\u7684\u7814\u7a76\u5df2\u786e\u8ba4\uff0c\u7535\u7f06\u622a\u9762\u5185\u9760\u8fd1\u5404\u82af\u7ebf\u5904\u7684\u78c1\u901a\u5bc6\u5ea6\u53ef\u5728 1 \u81f3 10 mT \u4e4b\u95f4\uff0c\u53d6\u51b3\u4e8e\u8d1f\u8f7d\u7535\u6d41\u548c\u51e0\u4f55\u7ed3\u6784\u2014\u2014\u8fd9\u4e9b\u6570\u503c\u5b8c\u5168\u5728\u611f\u5e94\u80fd\u91cf\u6536\u96c6\u7684\u5b9e\u7528\u8303\u56f4\u5185\u3002<\/span>\n  <\/p>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a78 ========== -->\n  <h2>8. Practical Implementation in Mining Cables<span class=\"cn\">\u5728\u77ff\u7528\u7535\u7f06\u4e2d\u7684\u5b9e\u9645\u5e94\u7528<\/span><\/h2>\n\n  <p>\n    The concept of inductive harvesting to power visibility LEDs in mining cables has been realized in commercial products. Prysmian Group&#8217;s <strong>TENAX-LUMEN<\/strong> cable incorporates an electroluminescent (EL) string embedded within a transparent polyurethane (PUR) outer sheath. While the EL mechanism differs from discrete LEDs (using phosphor excitation rather than a semiconductor junction), the principle of drawing energy from the cable&#8217;s own magnetic environment remains relevant. Chinese patent CN202473291U describes a mining luminous cable using photoelectric recurrence luminescent material (ZnS-based long-afterglow phosphors) applied to conductor surfaces, glowing under both energized and de-energized conditions.\n    <span class=\"cn\">\u5229\u7528\u611f\u5e94\u80fd\u91cf\u6536\u96c6\u4e3a\u77ff\u7528\u7535\u7f06\u4e2d\u7684\u53ef\u89c1\u6027 LED \u4f9b\u7535\u7684\u6982\u5ff5\u5df2\u5728\u5546\u4e1a\u4ea7\u54c1\u4e2d\u5f97\u5230\u5b9e\u73b0\u3002\u666e\u777f\u53f8\u66fc\u96c6\u56e2\u7684 <strong>TENAX-LUMEN<\/strong> \u7535\u7f06\u5728\u900f\u660e\u805a\u6c28\u916f\uff08PUR\uff09\u5916\u62a4\u5957\u4e2d\u5d4c\u5165\u4e86\u7535\u81f4\u53d1\u5149\uff08EL\uff09\u7ebf\u3002\u867d\u7136 EL \u673a\u5236\u4e0e\u5206\u7acb LED \u4e0d\u540c\uff08\u4f7f\u7528\u8367\u5149\u7c89\u6fc0\u53d1\u800c\u975e\u534a\u5bfc\u4f53\u7ed3\uff09\uff0c\u4f46\u4ece\u7535\u7f06\u81ea\u8eab\u78c1\u73af\u5883\u4e2d\u63d0\u53d6\u80fd\u91cf\u7684\u539f\u7406\u4f9d\u7136\u76f8\u5173\u3002\u4e2d\u56fd\u4e13\u5229 CN202473291U \u63cf\u8ff0\u4e86\u4e00\u79cd\u77ff\u7528\u53d1\u5149\u7535\u7f06\uff0c\u4f7f\u7528\u6d82\u8986\u5728\u5bfc\u4f53\u8868\u9762\u7684\u5149\u7535\u590d\u5408\u53d1\u5149\u6750\u6599\uff08\u57fa\u4e8e ZnS \u7684\u957f\u4f59\u8f89\u8367\u5149\u7c89\uff09\uff0c\u5728\u901a\u7535\u548c\u65ad\u7535\u6761\u4ef6\u4e0b\u5747\u53ef\u53d1\u5149\u3002<\/span>\n  <\/p>\n\n  <p>\n    For discrete LED implementations, the receiver coil and conditioning circuit can be integrated as a small, potted module positioned in the filler space of the cable during manufacturing. The module is entirely self-powered \u2014 it draws milliwatts from the magnetic field whenever current flows in the power cores. When the cable is de-energized (no current), the magnetic field vanishes, and the LEDs extinguish unless a backup mechanism (such as phosphorescent afterglow material or a small supercapacitor charged during operation) is included. The table below compares the three main approaches to cable visibility illumination.\n    <span class=\"cn\">\u5bf9\u4e8e\u5206\u7acb LED \u5b9e\u73b0\u65b9\u6848\uff0c\u63a5\u6536\u7ebf\u5708\u548c\u8c03\u7406\u7535\u8def\u53ef\u4ee5\u96c6\u6210\u4e3a\u4e00\u4e2a\u5c0f\u578b\u704c\u5c01\u6a21\u5757\uff0c\u5728\u5236\u9020\u8fc7\u7a0b\u4e2d\u653e\u7f6e\u5728\u7535\u7f06\u7684\u586b\u5145\u7a7a\u95f4\u5185\u3002\u8be5\u6a21\u5757\u5b8c\u5168\u81ea\u4f9b\u7535\u2014\u2014\u6bcf\u5f53\u52a8\u529b\u82af\u7ebf\u4e2d\u6709\u7535\u6d41\u6d41\u8fc7\u65f6\uff0c\u5b83\u4ece\u78c1\u573a\u4e2d\u63d0\u53d6\u6beb\u74e6\u7ea7\u529f\u7387\u3002\u5f53\u7535\u7f06\u65ad\u7535\uff08\u65e0\u7535\u6d41\uff09\u65f6\uff0c\u78c1\u573a\u6d88\u5931\uff0cLED \u7184\u706d\uff0c\u9664\u975e\u5305\u542b\u5907\u7528\u673a\u5236\uff08\u5982\u78f7\u5149\u4f59\u8f89\u6750\u6599\u6216\u5728\u8fd0\u884c\u671f\u95f4\u5145\u7535\u7684\u5c0f\u578b\u8d85\u7ea7\u7535\u5bb9\u5668\uff09\u3002\u4e0b\u8868\u6bd4\u8f83\u4e86\u4e09\u79cd\u4e3b\u8981\u7684\u7535\u7f06\u53ef\u89c1\u6027\u7167\u660e\u65b9\u6848\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 5 \u2014 Cable Visibility Illumination Methods Compared \u00b7 \u88685 \u2014 \u7535\u7f06\u53ef\u89c1\u6027\u7167\u660e\u65b9\u5f0f\u5bf9\u6bd4<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Method<\/th>\n          <th>Energy Source<\/th>\n          <th>Active When De-energized?<\/th>\n          <th>Advantages<\/th>\n          <th>Limitations<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr>\n          <td>Inductively-harvested LED<td class=\"cn-cell\">\u611f\u5e94\u6536\u96c6LED<\/td><\/td>\n          <td>Magnetic field of power cores (Faraday induction)<\/td>\n          <td>No (unless supercap backup)<\/td>\n          <td>No battery, no external power, self-powered, long life, can be bright<\/td>\n          <td>Only works when cable carries load current; requires circuit design space<\/td>\n        <\/tr>\n        <tr>\n          <td>Electroluminescent (EL) string<td class=\"cn-cell\">\u7535\u81f4\u53d1\u5149\u7ebf<\/td><\/td>\n          <td>AC driver circuit (which may itself be inductively powered or use a dedicated pilot wire)<\/td>\n          <td>Possible with battery\/supercap<\/td>\n          <td>360\u00b0 uniform glow, slim form factor, integrates into PUR sheath<\/td>\n          <td>EL phosphor degrades over time (5,000\u201310,000 hrs); requires AC driver<\/td>\n        <\/tr>\n        <tr>\n          <td>Phosphorescent \/ photoluminescent coating<td class=\"cn-cell\">\u78f7\u5149\/\u5149\u81f4\u53d1\u5149\u6d82\u5c42<\/td><\/td>\n          <td>Stored photon energy (charged by ambient light)<\/td>\n          <td>Yes (afterglow decays over hours)<\/td>\n          <td>Fully passive, no circuit, zero power consumption<\/td>\n          <td>Afterglow brightness limited; needs periodic light &#8220;charging&#8221;; dim in prolonged darkness<\/td>\n        <\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a79 ========== -->\n  <h2>9. Energy Budget: How Much Power Can Be Harvested?<span class=\"cn\">\u80fd\u91cf\u9884\u7b97\uff1a\u80fd\u6536\u96c6\u591a\u5c11\u529f\u7387\uff1f<\/span><\/h2>\n\n  <p>\n    Research published in <em>Applied Sciences<\/em> (MDPI) on energy harvesting from the stray electromagnetic field around power cables has demonstrated that inductive harvesters with optimized ferrite cores can produce RMS voltages exceeding 900&nbsp;mV at cable currents of 155&nbsp;A. At higher mining-cable currents of 300\u2013500&nbsp;A, and with resonant tuning, the harvested power can reach tens of milliwatts \u2014 far more than needed for a few LEDs.\n    <span class=\"cn\">\u53d1\u8868\u5728 <em>Applied Sciences<\/em>\uff08MDPI\uff09\u4e0a\u7684\u5173\u4e8e\u7535\u529b\u7535\u7f06\u5468\u56f4\u6742\u6563\u7535\u78c1\u573a\u80fd\u91cf\u6536\u96c6\u7684\u7814\u7a76\u8868\u660e\uff0c\u7ecf\u8fc7\u94c1\u6c27\u4f53\u78c1\u82af\u4f18\u5316\u7684\u611f\u5e94\u6536\u96c6\u5668\u5728\u7535\u7f06\u7535\u6d41 155 A \u65f6\u53ef\u4ea7\u751f\u8d85\u8fc7 900 mV \u7684\u6709\u6548\u503c\u7535\u538b\u3002\u5728\u77ff\u7528\u7535\u7f06\u66f4\u9ad8\u7684 300\u2013500 A \u7535\u6d41\u4e0b\uff0c\u914d\u5408\u8c10\u632f\u8c03\u8c10\uff0c\u6536\u96c6\u529f\u7387\u53ef\u8fbe\u6570\u5341\u6beb\u74e6\u2014\u2014\u8fdc\u8d85\u51e0\u9897 LED \u6240\u9700\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 6 \u2014 Typical LED Power Requirements vs. Available Harvested Power \u00b7 \u88686 \u2014 \u5178\u578bLED\u529f\u7387\u9700\u6c42\u4e0e\u53ef\u6536\u96c6\u529f\u7387\u5bf9\u6bd4<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Item<\/th>\n          <th>Voltage<\/th>\n          <th>Current<\/th>\n          <th>Power<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr><td>Standard red LED (visible indicator)<td class=\"cn-cell\">\u6807\u51c6\u7ea2\u8272LED<\/td><\/td><td>1.8\u20132.0 V<\/td><td>2\u201320 mA<\/td><td>4\u201340 mW<\/td><\/tr>\n        <tr><td>High-efficiency green LED<\/td><td>2.0\u20132.2 V<\/td><td>1\u20135 mA<\/td><td>2\u201311 mW<\/td><\/tr>\n        <tr><td>White LED (standard 5mm)<\/td><td>3.0\u20133.3 V<\/td><td>5\u201320 mA<\/td><td>15\u201366 mW<\/td><\/tr>\n        <tr><td>Ultra-low-power LED (0402 SMD)<\/td><td>1.8 V<\/td><td>0.5 mA<\/td><td>~1 mW<\/td><\/tr>\n        <tr><td colspan=\"4\" style=\"border-top:2px solid var(--accent-primary);font-weight:600;color:var(--text-body)\">Harvestable Power (estimated, 300 A, 50 Hz, optimized ferrite-core coil at 25 mm from power core)<\/td><\/tr>\n        <tr><td>Estimated available power<td class=\"cn-cell\">\u4f30\u8ba1\u53ef\u7528\u529f\u7387<\/td><\/td><td>2\u20135 V (rectified)<\/td><td>5\u201330 mA<\/td><td><strong>10\u2013150 mW<\/strong><\/td><\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <p>\n    The harvested power budget of 10\u2013150&nbsp;mW is comfortably above the requirement for several ultra-low-power LEDs distributed along the cable&#8217;s length. In practice, a harvester module might be embedded every 5\u201310 meters, each powering one or more LEDs visible through a translucent or transparent PUR sheath section. The total power drawn from the magnetic field is negligible compared to the kilowatts flowing through the power cores \u2014 typically less than 0.001% of the transmitted power.\n    <span class=\"cn\">10\u2013150 mW \u7684\u6536\u96c6\u529f\u7387\u9884\u7b97\u660e\u663e\u9ad8\u4e8e\u6cbf\u7535\u7f06\u957f\u5ea6\u5206\u5e03\u7684\u6570\u9897\u8d85\u4f4e\u529f\u8017 LED \u7684\u9700\u6c42\u3002\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u53ef\u6bcf\u9694 5\u201310 \u7c73\u5d4c\u5165\u4e00\u4e2a\u6536\u96c6\u5668\u6a21\u5757\uff0c\u6bcf\u4e2a\u6a21\u5757\u9a71\u52a8\u4e00\u9897\u6216\u591a\u9897\u901a\u8fc7\u534a\u900f\u660e\u6216\u900f\u660e PUR \u62a4\u5957\u6bb5\u53ef\u89c1\u7684 LED\u3002\u4ece\u78c1\u573a\u4e2d\u63d0\u53d6\u7684\u603b\u529f\u7387\u4e0e\u6d41\u8fc7\u52a8\u529b\u82af\u7ebf\u7684\u5343\u74e6\u7ea7\u529f\u7387\u76f8\u6bd4\u53ef\u5ffd\u7565\u4e0d\u8ba1\u2014\u2014\u901a\u5e38\u4e0d\u5230\u4f20\u8f93\u529f\u7387\u7684 0.001%\u3002<\/span>\n  <\/p>\n\n  <div class=\"callout callout-amber\">\n    <div class=\"callout-title\">Safety Note \u00b7 \u5b89\u5168\u8bf4\u660e<\/div>\n    <p style=\"margin-bottom:0;\">\n      The inductive harvesting system is inherently isolated from the high-voltage power circuit. There is no galvanic (metallic) connection between the power cores and the LED circuit. The receiver coil is magnetically coupled only. This means the LED circuit operates at extra-low voltage (typically under 5&nbsp;V DC), fully compliant with safety requirements for touch-safe circuits. A failure of the LED module cannot cause a fault on the high-voltage system, and a fault on the high-voltage system cannot send dangerous voltage to the LED circuit.\n      <span class=\"cn\">\u611f\u5e94\u80fd\u91cf\u6536\u96c6\u7cfb\u7edf\u4e0e\u9ad8\u538b\u7535\u529b\u56de\u8def\u5929\u7136\u9694\u79bb\u3002\u52a8\u529b\u82af\u7ebf\u4e0e LED \u7535\u8def\u4e4b\u95f4\u6ca1\u6709\u7535\u6c14\uff08\u91d1\u5c5e\uff09\u8fde\u63a5\u3002\u63a5\u6536\u7ebf\u5708\u4ec5\u901a\u8fc7\u78c1\u8026\u5408\u3002\u8fd9\u610f\u5473\u7740 LED \u7535\u8def\u5de5\u4f5c\u5728\u7279\u4f4e\u7535\u538b\uff08\u901a\u5e38\u4f4e\u4e8e 5 V \u76f4\u6d41\uff09\uff0c\u5b8c\u5168\u7b26\u5408\u5b89\u5168\u89e6\u78b0\u7535\u8def\u7684\u8981\u6c42\u3002LED \u6a21\u5757\u7684\u6545\u969c\u4e0d\u4f1a\u5bfc\u81f4\u9ad8\u538b\u7cfb\u7edf\u6545\u969c\uff0c\u9ad8\u538b\u7cfb\u7edf\u7684\u6545\u969c\u4e5f\u4e0d\u4f1a\u5411 LED \u7535\u8def\u4f20\u9001\u5371\u9669\u7535\u538b\u3002<\/span>\n    <\/p>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a710 ========== -->\n  <h2>10. Summary: The Physics Chain from Power Core to LED<span class=\"cn\">\u603b\u7ed3\uff1a\u4ece\u52a8\u529b\u82af\u7ebf\u5230LED\u7684\u7269\u7406\u94fe<\/span><\/h2>\n\n  <p>\n    The complete chain of physics that allows an LED to illuminate inside a mining cable without any physical electrical connection to the power circuit can be summarized in five steps, each grounded in established electromagnetic theory.\n    <span class=\"cn\">\u4f7f LED \u5728\u77ff\u7528\u7535\u7f06\u5185\u90e8\u65e0\u9700\u4e0e\u7535\u529b\u56de\u8def\u6709\u4efb\u4f55\u7269\u7406\u7535\u6c14\u8fde\u63a5\u5373\u53ef\u70b9\u4eae\u7684\u5b8c\u6574\u7269\u7406\u94fe\u53ef\u4ee5\u5f52\u7eb3\u4e3a\u4e94\u4e2a\u6b65\u9aa4\uff0c\u6bcf\u4e00\u6b65\u90fd\u57fa\u4e8e\u6210\u719f\u7684\u7535\u78c1\u7406\u8bba\u3002<\/span>\n  <\/p>\n\n  <div class=\"tw\">\n    <div class=\"tc\">Table 7 \u2014 The Five-Step Physics Chain \u00b7 \u88687 \u2014 \u4e94\u6b65\u7269\u7406\u94fe<\/div>\n    <table>\n      <thead>\n        <tr>\n          <th>Step<\/th>\n          <th>Physical Phenomenon<\/th>\n          <th>Governing Law<\/th>\n          <th>What Happens<\/th>\n          <th>\u7269\u7406\u8fc7\u7a0b<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr>\n          <td>1<\/td>\n          <td>Current flows in power core<\/td>\n          <td>Ohm&#8217;s law \/ circuit theory<\/td>\n          <td>AC current (50\/60 Hz, 200\u2013500 A) flows through tinned copper Class 5 conductors<\/td>\n          <td class=\"cn-cell\">\u4ea4\u6d41\u7535\u6d41\u901a\u8fc7\u9540\u9521\u94dc5\u7c7b\u5bfc\u4f53<\/td>\n        <\/tr>\n        <tr>\n          <td>2<\/td>\n          <td>Magnetic field is generated<\/td>\n          <td>Amp\u00e8re&#8217;s law: B = \u03bc\u2080I\/(2\u03c0r)<\/td>\n          <td>A time-varying magnetic field (1\u201310 mT range) surrounds each power core<\/td>\n          <td class=\"cn-cell\">\u65f6\u53d8\u78c1\u573a\uff081\u201310 mT \u8303\u56f4\uff09\u73af\u7ed5\u6bcf\u6839\u52a8\u529b\u82af\u7ebf<\/td>\n        <\/tr>\n        <tr>\n          <td>3<\/td>\n          <td>Magnetic flux passes through receiver coil<\/td>\n          <td>\u03a6 = B \u00b7 A \u00b7 cos(\u03b8)<\/td>\n          <td>The oscillating magnetic flux threads through the N-turn receiver coil positioned nearby<\/td>\n          <td class=\"cn-cell\">\u632f\u8361\u78c1\u901a\u7a7f\u8fc7\u9644\u8fd1\u7684N\u531d\u63a5\u6536\u7ebf\u5708<\/td>\n        <\/tr>\n        <tr>\n          <td>4<\/td>\n          <td>EMF is induced in receiver coil<\/td>\n          <td>Faraday&#8217;s law: EMF = \u2212N\u00b7d\u03a6\/dt<\/td>\n          <td>A voltage (AC) is induced in the coil; amplified by LC resonance and ferrite core<\/td>\n          <td class=\"cn-cell\">\u7ebf\u5708\u4e2d\u611f\u5e94\u51fa\u4ea4\u6d41\u7535\u538b\uff1b\u7ecfLC\u8c10\u632f\u548c\u94c1\u6c27\u4f53\u78c1\u82af\u653e\u5927<\/td>\n        <\/tr>\n        <tr>\n          <td>5<\/td>\n          <td>LED illuminates<\/td>\n          <td>Semiconductor junction physics<\/td>\n          <td>Rectified DC forward-biases the LED; photons are emitted \u2014 the cable glows<\/td>\n          <td class=\"cn-cell\">\u6574\u6d41\u540e\u7684\u76f4\u6d41\u4f7fLED\u6b63\u5411\u5bfc\u901a\uff0c\u53d1\u5c04\u5149\u5b50\u2014\u2014\u7535\u7f06\u53d1\u5149<\/td>\n        <\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n\n  <p>\n    This elegant chain \u2014 from Amp\u00e8re to Faraday to semiconductor physics \u2014 represents one of the most practical and safety-enhancing applications of fundamental electromagnetic theory in modern mining cable engineering. It is a technology that converts an unavoidable by-product of power transmission (the stray magnetic field) into a life-saving visibility feature, with zero additional wiring, zero external power, and zero compromise to the cable&#8217;s primary electrical function.\n    <span class=\"cn\">\u8fd9\u4e00\u4f18\u7f8e\u7684\u94fe\u6761\u2014\u2014\u4ece\u5b89\u57f9\u5230\u6cd5\u62c9\u7b2c\u518d\u5230\u534a\u5bfc\u4f53\u7269\u7406\u2014\u2014\u4ee3\u8868\u4e86\u57fa\u7840\u7535\u78c1\u7406\u8bba\u5728\u73b0\u4ee3\u77ff\u7528\u7535\u7f06\u5de5\u7a0b\u4e2d\u6700\u5b9e\u7528\u3001\u6700\u80fd\u589e\u5f3a\u5b89\u5168\u6027\u7684\u5e94\u7528\u4e4b\u4e00\u3002\u8fd9\u9879\u6280\u672f\u5c06\u7535\u529b\u4f20\u8f93\u4e0d\u53ef\u907f\u514d\u7684\u526f\u4ea7\u54c1\uff08\u6742\u6563\u78c1\u573a\uff09\u8f6c\u5316\u4e3a\u62ef\u6551\u751f\u547d\u7684\u53ef\u89c1\u6027\u529f\u80fd\uff0c\u65e0\u9700\u989d\u5916\u5e03\u7ebf\u3001\u65e0\u9700\u5916\u90e8\u7535\u6e90\uff0c\u4e14\u4e0d\u5f71\u54cd\u7535\u7f06\u7684\u4e3b\u8981\u7535\u6c14\u529f\u80fd\u3002<\/span>\n  <\/p>\n\n  <hr class=\"sep\">\n\n  <!-- ========== \u00a711 ========== -->\n  <h2>11. About Anhui Feichun Special Cable Co., Ltd.<span class=\"cn\">\u5173\u4e8e\u5b89\u5fbd\u98de\u7eaf\u7279\u79cd\u7535\u7f06\u6709\u9650\u516c\u53f8<\/span><\/h2>\n\n  <p>\n    Anhui Feichun Special Cable Co., Ltd. (\u5b89\u5fbd\u98de\u7eaf\u7279\u79cd\u7535\u7f06\u6709\u9650\u516c\u53f8) designs and manufactures high-performance flexible cables for mining, crane, port, and industrial-automation applications. With products aligned to DIN&nbsp;VDE&nbsp;0250, IEC&nbsp;60228, IEC&nbsp;60502, ICEA&nbsp;S-75-381, and AS\/NZS&nbsp;1802\/2802, Feichun delivers engineering-grade cable solutions worldwide. Our R&amp;D team is actively developing next-generation visibility technologies for mining trailing cables, including inductively-powered LED systems and advanced high-contrast PUR sheath formulations.\n    <span class=\"cn\">\u5b89\u5fbd\u98de\u7eaf\u7279\u79cd\u7535\u7f06\u6709\u9650\u516c\u53f8\u4e13\u6ce8\u4e8e\u77ff\u5c71\u3001\u8d77\u91cd\u673a\u3001\u6e2f\u53e3\u548c\u5de5\u4e1a\u81ea\u52a8\u5316\u9886\u57df\u9ad8\u6027\u80fd\u67d4\u6027\u7535\u7f06\u7684\u8bbe\u8ba1\u548c\u5236\u9020\u3002\u4ea7\u54c1\u7cfb\u5217\u7b26\u5408 DIN VDE 0250\u3001IEC 60228\u3001IEC 60502\u3001ICEA S-75-381 \u548c AS\/NZS 1802\/2802 \u6807\u51c6\uff0c\u9762\u5411\u5168\u7403\u63d0\u4f9b\u5de5\u7a0b\u7ea7\u7535\u7f06\u89e3\u51b3\u65b9\u6848\u3002\u6211\u4eec\u7684\u7814\u53d1\u56e2\u961f\u6b63\u5728\u79ef\u6781\u5f00\u53d1\u77ff\u7528\u62d6\u62fd\u7535\u7f06\u7684\u4e0b\u4e00\u4ee3\u53ef\u89c1\u6027\u6280\u672f\uff0c\u5305\u62ec\u611f\u5e94\u4f9b\u7535 LED \u7cfb\u7edf\u548c\u5148\u8fdb\u7684\u9ad8\u5bf9\u6bd4\u5ea6 PUR \u62a4\u5957\u914d\u65b9\u3002<\/span>\n  <\/p>\n\n  <!-- CONTACT -->\n  <div class=\"contact\">\n    <h3>Contact Feichun Technical Sales <span class=\"cn\">\u8054\u7cfb\u98de\u7eaf\u6280\u672f\u9500\u552e<\/span><\/h3>\n    <div class=\"cg\">\n      <div class=\"ci\">\n        <div class=\"cl\">Technical Inquiries \u00b7 \u6280\u672f\u54a8\u8be2<\/div>\n        <div class=\"cv\"><a href=\"mailto:tech@feichuncables.com\" rel=\"nofollow noopener\">tech@feichuncables.com<\/a><\/div>\n      <\/div>\n      <div class=\"ci\">\n        <div class=\"cl\">Sales \u2014 Zihao Yang<\/div>\n        <div class=\"cv\"><a href=\"mailto:zihao.yang@feichuncables.com\" rel=\"nofollow noopener\">zihao.yang@feichuncables.com<\/a><\/div>\n      <\/div>\n      <div class=\"ci\">\n        <div class=\"cl\">Sales \u2014 Ziyu Huang<\/div>\n        <div class=\"cv\"><a href=\"mailto:ziyu.huang@feichuncables.com\" rel=\"nofollow noopener\">ziyu.huang@feichuncables.com<\/a><\/div>\n      <\/div>\n      <div class=\"ci\">\n        <div class=\"cl\">WhatsApp<\/div>\n        <div class=\"cv\"><a href=\"https:\/\/wa.me\/8613855123218\" rel=\"nofollow noopener\" target=\"_blank\">+86 138 5512 3218<\/a><\/div>\n      <\/div>\n    <\/div>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- REFERENCES -->\n  <div class=\"refs\">\n    <h3>References &amp; Sources <span class=\"cn\">\u53c2\u8003\u6765\u6e90<\/span><\/h3>\n    <ol class=\"ref-list\">\n      <li>Faraday, M. (1831). &#8220;Experimental Researches in Electricity.&#8221; <em>Philosophical Transactions of the Royal Society of London.<\/em> \u2014 Wikipedia overview: <a href=\"https:\/\/en.wikipedia.org\/wiki\/Faraday%27s_law_of_induction\" rel=\"nofollow noopener\" target=\"_blank\">en.wikipedia.org<\/a><\/li>\n      <li>Wikipedia, &#8220;Electromagnetic induction.&#8221; <a href=\"https:\/\/en.wikipedia.org\/wiki\/Electromagnetic_induction\" rel=\"nofollow noopener\" target=\"_blank\">en.wikipedia.org<\/a><\/li>\n      <li>Physics LibreTexts, &#8220;22.1: Magnetic Flux, Induction, and Faraday&#8217;s Law.&#8221; <a href=\"https:\/\/phys.libretexts.org\/Bookshelves\/University_Physics\/Physics_(Boundless)\/22:_Induction_AC_Circuits_and_Electrical_Technologies\/22.1:_Magnetic_Flux_Induction_and_Faradays_Law\" rel=\"nofollow noopener\" target=\"_blank\">phys.libretexts.org<\/a><\/li>\n      <li>Physics LibreTexts, &#8220;12.6: Amp\u00e8re&#8217;s Law.&#8221; <a href=\"https:\/\/phys.libretexts.org\/Bookshelves\/University_Physics\/University_Physics_(OpenStax)\/University_Physics_II_-_Thermodynamics_Electricity_and_Magnetism_(OpenStax)\/12:_Sources_of_Magnetic_Fields\/12.06:_Amperes_Law\" rel=\"nofollow noopener\" target=\"_blank\">phys.libretexts.org<\/a><\/li>\n      <li>Khan, F. et al. (2016). &#8220;Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications.&#8221; <em>PMC \/ Sensors.<\/em> <a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC4992547\/\" rel=\"nofollow noopener\" target=\"_blank\">pmc.ncbi.nlm.nih.gov<\/a><\/li>\n      <li>Moghe, R. et al. (2011). &#8220;Energy Harvesting from Electromagnetic Energy Radiating from AC Power Lines.&#8221; CMU. <a href=\"https:\/\/users.ece.cmu.edu\/~vikramg\/docs\/hotemnets11.pdf\" rel=\"nofollow noopener\" target=\"_blank\">users.ece.cmu.edu<\/a><\/li>\n      <li>Prysmian Group, &#8220;TENAX-LUMEN \u2014 Self-Luminous Power Cable for Mining.&#8221; <a href=\"https:\/\/www.prysmian.com\/en\/tenax-lumen\" rel=\"nofollow noopener\" target=\"_blank\">prysmian.com<\/a><\/li>\n      <li>Prysmian Group, &#8220;Cable Solutions for Mining Industry.&#8221; <a href=\"https:\/\/www.prysmian.com\/en\/markets\/specialties\/industries\/mining\" rel=\"nofollow noopener\" target=\"_blank\">prysmian.com\/mining<\/a><\/li>\n      <li>CN202473291U \u2014 &#8220;Mining luminous cable&#8221; (Chinese patent). <a href=\"https:\/\/patents.google.com\/patent\/CN202473291U\/en\" rel=\"nofollow noopener\" target=\"_blank\">patents.google.com<\/a><\/li>\n      <li>Arrow Electronics, &#8220;Faraday&#8217;s Law &amp; Electromagnetic Induction \u2014 How Transformers Work.&#8221; <a href=\"https:\/\/www.arrow.com\/en\/research-and-events\/articles\/how-transformers-work\" rel=\"nofollow noopener\" target=\"_blank\">arrow.com<\/a><\/li>\n      <li>Electronics Tutorials, &#8220;Electromagnetic Induction and Faraday&#8217;s Law of Induction.&#8221; <a href=\"https:\/\/www.electronics-tutorials.ws\/electromagnetism\/electromagnetic-induction.html\" rel=\"nofollow noopener\" target=\"_blank\">electronics-tutorials.ws<\/a><\/li>\n      <li>Electrical4U, &#8220;Faraday&#8217;s Laws of Electromagnetic Induction.&#8221; <a href=\"https:\/\/www.electrical4u.com\/faraday-law-of-electromagnetic-induction\/\" rel=\"nofollow noopener\" target=\"_blank\">electrical4u.com<\/a><\/li>\n      <li>MDPI Applied Sciences (2023), &#8220;Numerical and Analytical Analysis of Low-Frequency Magnetic Fields Generated by Three-Phase Underground Power Cables with Solid Bonding.&#8221; <a href=\"https:\/\/www.mdpi.com\/2076-3417\/13\/10\/6328\" rel=\"nofollow noopener\" target=\"_blank\">mdpi.com<\/a><\/li>\n      <li>ELEK Software, &#8220;Magnetic Fields from High Voltage Power Cables.&#8221; <a href=\"https:\/\/elek.com\/articles\/magnetic-fields-from-high-voltage-power-cables\/\" rel=\"nofollow noopener\" target=\"_blank\">elek.com<\/a><\/li>\n      <li>SimScale, &#8220;What is Electromagnetic Induction?&#8221; <a href=\"https:\/\/www.simscale.com\/docs\/simwiki\/electromagnetics\/what-is-electromagnetic-induction\/\" rel=\"nofollow noopener\" target=\"_blank\">simscale.com<\/a><\/li>\n      <li>Nexans Deutschland GmbH, &#8220;POWERMINE\u00ae (N)TMCGEH3S 6\/10 kV.&#8221; <a href=\"https:\/\/www.nexans.de\/eservice\/Germany-en\/navigate_328846\/POWERMINE_N_TMCGEH3S_6_10_kV.html\" rel=\"nofollow noopener\" target=\"_blank\">nexans.de<\/a><\/li>\n      <li>Feichun Special Cable, &#8220;What is DIN VDE 0250 Cable?&#8221; <a href=\"https:\/\/feichuncables.com\/blog\/what-is-din-vde-0250-cable\/\" rel=\"nofollow noopener\" target=\"_blank\">feichuncables.com<\/a><\/li>\n    <\/ol>\n  <\/div>\n\n  <hr class=\"sep\">\n\n  <!-- TAGS -->\n  <div class=\"tags\">\n    <div class=\"tags-lbl\">Related Tags<\/div>\n    <div class=\"tag-list\">\n      <span class=\"tag\">inductive energy harvesting<\/span>\n      <span class=\"tag\">electromagnetic induction mining cable<\/span>\n      <span class=\"tag\">Faraday&#8217;s law cable LED<\/span>\n      <span class=\"tag\">self-luminous mining cable<\/span>\n      <span class=\"tag\">TENAX-LUMEN<\/span>\n      <span class=\"tag\">(N)TMCGEH3S high-visibility<\/span>\n      <span class=\"tag\">wireless LED power cable<\/span>\n      <span class=\"tag\">magnetic field power core<\/span>\n      <span class=\"tag\">AC cable energy harvesting<\/span>\n      <span class=\"tag\">receiver coil induction LED<\/span>\n      <span class=\"tag\">DIN VDE 0250-813<\/span>\n      <span class=\"tag\">medium voltage mining cable<\/span>\n      <span class=\"tag\">EPR insulated trailing cable<\/span>\n      <span class=\"tag\">IEC 60228 Class 5<\/span>\n      <span class=\"tag\">Amp\u00e8re&#8217;s law cable field<\/span>\n      <span class=\"tag\">LC resonant energy harvesting<\/span>\n      <span class=\"tag\">ferrite core harvester<\/span>\n      <span class=\"tag\">mining cable safety visibility<\/span>\n      <span class=\"tag\">Feichun cable<\/span>\n      <span class=\"tag\">\u5b89\u5fbd\u98de\u7eaf\u7535\u7f06<\/span>\n    <\/div>\n  <\/div>\n\n<\/article>\n<\/main>\n\n<!-- ======================== FOOTER ======================== -->\n<footer class=\"site-ft\">\n<div class=\"wrap\">\n  <p>&copy; 2026 Anhui Feichun Special Cable Co., Ltd. (\u5b89\u5fbd\u98de\u7eaf\u7279\u79cd\u7535\u7f06\u6709\u9650\u516c\u53f8) &middot; All rights reserved.<\/p>\n  <p style=\"margin-top:5px;\">\n    <a href=\"https:\/\/feichuncables.com\" rel=\"nofollow noopener\" target=\"_blank\">feichuncables.com<\/a> &middot;\n    <a href=\"mailto:tech@feichuncables.com\" rel=\"nofollow noopener\">tech@feichuncables.com<\/a> &middot;\n    <a href=\"https:\/\/wa.me\/8613855123218\" rel=\"nofollow noopener\" target=\"_blank\">WhatsApp: +86 138 5512 3218<\/a>\n  <\/p>\n<\/div>\n<\/footer>\n\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"Consider a medium-voltage mining trailing cable \u2014 for instance, an (N)TMCGEH3S rated 6\/10 kV \u2014 carrying hundreds of amperes of alternating current through its three power cores to an electric rope shovel in an open-pit mine. Somewhere inside the same cable, a tiny LED glows steadily, making the cable visible to operators in darkness. Yet that LED has no wire, no contact, no physical electrical connection to the power cores. How is this possible?\n\u8bbe\u60f3\u4e00\u6839\u4e2d\u538b\u77ff\u7528\u62d6\u62fd\u7535\u7f06\u2014\u2014\u4f8b\u5982\u989d\u5b9a 6\/10 kV \u7684 (N)TMCGEH3S\u2014\u2014\u901a\u8fc7\u4e09\u6839\u52a8\u529b\u7ebf\u82af\u5411\u9732\u5929\u77ff\u7684\u7535\u94f2\u8f93\u9001\u6570\u767e\u5b89\u57f9\u7684\u4ea4\u6d41\u7535\u3002\u5728\u540c\u4e00\u6839\u7535\u7f06\u5185\u90e8\u67d0\u5904\uff0c\u4e00\u9897\u5fae\u5c0f\u7684 LED \u7a33\u5b9a\u53d1\u5149\uff0c\u4f7f\u7535\u7f06\u5728\u9ed1\u6697\u4e2d\u5bf9\u64cd\u4f5c\u4eba\u5458\u53ef\u89c1\u3002\u4f46\u8be5 LED \u4e0e\u52a8\u529b\u7ebf\u82af\u4e4b\u95f4\u6ca1\u6709\u5bfc\u7ebf\u3001\u6ca1\u6709\u89e6\u70b9\u3001\u6ca1\u6709\u4efb\u4f55\u7269\u7406\u7535\u6c14\u8fde\u63a5\u3002\u8fd9\u662f\u5982\u4f55\u505a\u5230\u7684\uff1f","protected":false},"author":1,"featured_media":6743,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"csco_singular_sidebar":"left","csco_page_header_type":"title","csco_page_load_nextpost":"","footnotes":""},"categories":[66,93,7],"tags":[42736,42733,42771,42764,42741,42551,16,42766,5857,5849,42745,42732,42758,42763,29100,171,42756,42729,4491,917,42742,42759,152,107,42757,42761,90,2924,42772,42746,42731,42760,42769,42767,42738,42734,42762,42740,5480,111,42770,42739,42768,139,204,42749,41574,42747,42743,42750,42735,17,42730,42755,42751,42774,5426,42773,42765,42737,42744,10130,42752,42748,42753,42754,11898],"class_list":["post-6742","post","type-post","status-publish","format-standard","has-post-thumbnail","category-common-problems-encountered-in-cable-applications","category-mining-cable-with-self-sufficient-leds","category-mining-trailing-cable","tag-ntmcgeh3s-high-visibility-cable","tag-ac-cable-energy-harvesting-50hz","tag-air-core-transformer-principle-mining-cable-led","tag-ampere-law-magnetic-field-calculation-power-conductor","tag-amperes-law-cable-magnetic-field","tag-current-transformer-energy-harvesting","tag-din-vde-0250","tag-din-vde-0250-813-high-visibility-trailing-cable-specification","tag-din-vde-0250-813-trailing-cable","tag-electroluminescent-mining-cable","tag-electromagnetic-field-energy-harvesting-power-line","tag-electromagnetic-induction-mining-cable","tag-electromagnetic-induction-receiver-coil-led-power-cable","tag-energy-harvesting-stray-electromagnetic-field-power-cable","tag-epr-insulated-trailing-cable","tag-explosion-proof-mining-cable","tag-faraday-law-electromagnetic-induction-energy-harvesting-cable-led","tag-faradays-law-cable-led","tag-feichun-cable","tag-feichun-mining-cable","tag-ferrite-core-energy-harvester","tag-ferrite-core-inductive-harvester-for-mining-cable-led","tag-heavy-duty-mining-cable","tag-heavy-duty-e-loader-mining-cable","tag-how-does-magnetic-field-light-up-led-in-mining-cable","tag-how-tenax-lumen-cable-glows-without-wires","tag-icea-s-75-381","tag-iec-60228-class-5-conductor","tag-iec-60332-1-2-flame-retardant-self-luminous-cable","tag-inductive-coupling-led-lighting","tag-inductive-energy-harvesting","tag-inductive-harvesting-from-power-cable-magnetic-field","tag-inductively-powered-led-visibility-system-mining","tag-lc-resonant-circuit-energy-harvesting-50hz-power-line","tag-lc-resonant-energy-harvesting","tag-magnetic-field-power-core-induction","tag-magnetic-flux-density-around-three-phase-mining-cable","tag-magnetic-resonance-coupling-led","tag-medium-voltage-mining-cable-6-10kv","tag-mining-cable","tag-mining-cable-electromagnetic-field-simulation-comsol","tag-mining-cable-safety-visibility","tag-mining-cable-visibility-technology-comparison-electroluminescent-vs-led","tag-mining-cables","tag-mining-trailing-cable","tag-mining-trailing-cable-led-illumination","tag-nexans-powermine-cable","tag-open-pit-mining-cable-visibility","tag-prysmian-tenax-lumen-alternative","tag-pur-sheathed-high-visibility-cable","tag-receiver-coil-induction-led","tag-reeling-cable","tag-self-luminous-mining-cable","tag-self-luminous-mining-trailing-cable-without-electrical-connection","tag-self-powered-led-cable-system","tag-supercapacitor-backup-led-mining-cable-de-energized-visibility","tag-tenax-lumen","tag-three-phase-cable-magnetic-field-partial-cancellation","tag-wireless-led-illumination-inside-medium-voltage-cable","tag-wireless-led-power-cable","tag-wireless-power-transfer-cable","tag-10130","tag-led","tag-42748","tag-42753","tag-11898","cs-entry"],"_links":{"self":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/6742","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/comments?post=6742"}],"version-history":[{"count":1,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/6742\/revisions"}],"predecessor-version":[{"id":6744,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/6742\/revisions\/6744"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/media\/6743"}],"wp:attachment":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/media?parent=6742"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/categories?post=6742"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/feichuncables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