{"id":150,"date":"2015-08-31T11:17:00","date_gmt":"2015-08-31T11:17:00","guid":{"rendered":"http:\/\/machineryequipmentonline.com\/video-equipment\/uncategorized\/flat-panel-television-receiversprinciple-of-operation-of-resonant-converters\/"},"modified":"2015-08-31T11:17:00","modified_gmt":"2015-08-31T11:17:00","slug":"flat-panel-television-receiversprinciple-of-operation-of-resonant-converters","status":"publish","type":"post","link":"http:\/\/machineryequipmentonline.com\/video-equipment\/flat-panel-television-receiversprinciple-of-operation-of-resonant-converters\/","title":{"rendered":"Flat panel television receivers:Principle of operation of resonant converters"},"content":{"rendered":"<div class=\"bevtd6a0dbc3e742ef\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '61e5902552e2353963d8d2f1bd1f4a8f',\n\t\t'format' : 'iframe',\n\t\t'height' : 250,\n\t\t'width' : 300,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/61e5902552e2353963d8d2f1bd1f4a8f\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.bevtd6a0dbc3e742ef {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.bevtd6a0dbc3e742ef {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.bevtd6a0dbc3e742ef {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.bevtd6a0dbc3e742ef {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.bevtd6a0dbc3e742ef {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<h3 align=\"justify\">Principle of operation of resonant converters<\/h3>\n<p align=\"justify\">When a resonant circuit is fed with a +10 V step voltage, it oscillates resulting in what is known as ringing. The capacitor charges up to 10 V, at which point current ceases and the capacitor begins to discharge causing current to flow in the opposite direction transferring energy from the capacitor to the inductor. The current continues to flow in that direction until the capacitor is fully charged to -10 V at which point, current ceases and swings back in the opposite direction and so on as illustrated in Figure 16.24. As can be seen, the resonant waveform has zero current when the voltage is at a peak and zero voltage when it crosses the 0 V line. Resonant converters use this fact to ensure that switching takes place at one of these points.  <\/p>\n<h3 align=\"justify\">Steady-state analysis of a basic ZCS resonant converter Refer to Figures 16.25 and 16.26. In the steady state, load current <i>I<\/i>L2 is con- stant. The cycle starts when MOSFET Q1 is turned ON by a control pulse while D1 is also ON. With capacitor C1 short circuited by D1, <i>I<\/i>L1 flows through inductor L1 and diode D1. <i>I<\/i>L1 increases in a linear fashion and<\/h3>\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-UJ-c8WMUuao\/VeQ3WBc371I\/AAAAAAAB5fU\/AU8PnJs0nb8\/s1600-h\/Television-and-Video-Technology-0050.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-right-width: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top-width: 0px; border-bottom-width: 0px; border-left-width: 0px; padding-top: 0px\" title=\"Television and Video Technology-0050\" border=\"0\" alt=\"Television and Video Technology-0050\" src=\"http:\/\/lh3.googleusercontent.com\/-L01vke41J6U\/VeQ3jvkmLsI\/AAAAAAAB5fk\/Qrhn6U5rcK8\/Television-and-Video-Technology-0050%25255B1%25255D.jpg?imgmax=800\" width=\"403\" height=\"432\" \/><\/a><\/p>\n<p align=\"justify\">energy is stored in the inductor. When <i>I<\/i>L1 = <i>I<\/i>L2, diode current drops to zero and the diode turns OFF naturally (ZCS). With D1 open circuit, L1 and C1 form a resonant circuit. <i>I<\/i>L1 increases to a peak in a sinusoidal manner and energy is transferred to the capacitor as <i>I<\/i>C1 charges capacitor C1. Once <i>I<\/i>L1 reaches its peak (at which point the voltage across C1 is equal to the input voltage <i>V<\/i>IN), it begins to drop and when <i>I<\/i>L1 = <i>I<\/i>L2, C1 is fully charged and <i>I<\/i>C1 drops to zero. When <i>I<\/i>L1 drops further below <i>I<\/i>L2, <i>I<\/i>C1 is reversed and the capacitor begins to discharge transferring energy to inductor L2. When <i>I<\/i>L1 drops to zero, MOSFET Q1 switches OFF naturally (ZCS) keeping <i>I<\/i>L1 at zero. The capacitor continues to discharge and when its voltage falls to zero and <i>I<\/i>C1 = <i>I<\/i>L2, diode D1 switches ON naturally (ZCS) to short circuit C1 and break the resonant circuit. This state continues until Q1 is switched on by a control pulse to commence the next cycle and so on. As can be seen,<\/p><div class=\"bwhxx6a0dbc3e74497\" ><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-0778475562755157\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- 300x600 television-and-video -->\n<ins class=\"adsbygoogle\"\n     style=\"display:inline-block;width:300px;height:600px\"\n     data-ad-client=\"ca-pub-0778475562755157\"\n     data-ad-slot=\"6549443290\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.bwhxx6a0dbc3e74497 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.bwhxx6a0dbc3e74497 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.bwhxx6a0dbc3e74497 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.bwhxx6a0dbc3e74497 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.bwhxx6a0dbc3e74497 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<div class=\"pjipm6a0dbc3e743d6\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '0c1eb4c533eaedb7b996f49a5a4983a9',\n\t\t'format' : 'iframe',\n\t\t'height' : 300,\n\t\t'width' : 160,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/0c1eb4c533eaedb7b996f49a5a4983a9\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.pjipm6a0dbc3e743d6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.pjipm6a0dbc3e743d6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.pjipm6a0dbc3e743d6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.pjipm6a0dbc3e743d6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.pjipm6a0dbc3e743d6 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-TUnA3USjS4I\/VeQ3lswue0I\/AAAAAAAB5fs\/GjA98zhL2Q4\/s1600-h\/Television-and-Video-Technology-0051%25255B2%25255D.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-right-width: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top-width: 0px; border-bottom-width: 0px; border-left-width: 0px; padding-top: 0px\" title=\"Television and Video Technology-0051\" border=\"0\" alt=\"Television and Video Technology-0051\" src=\"http:\/\/lh3.googleusercontent.com\/--SdKJI63fRU\/VeQ30shYT5I\/AAAAAAAB5gQ\/5EcXw0pAtxc\/Television-and-Video-Technology-0051%25255B1%25255D.jpg?imgmax=800\" width=\"395\" height=\"358\" \/><\/a><\/p>\n<p align=\"justify\">the period Q1 remains ON is fixed by the resonant frequency of L1 and C1 while the time it is OFF is determined by the control pulse which is varied as necessary to regulate the voltage. This type of resonant converter is known as \u2018<i>fixed on-time<\/i>, <i>varied off-time<\/i>\u2019. The ON period of the power MOS- FET switch is the resonant period of L1\/C1, known as the <i>tan<\/i><i>k<\/i>. For heavy loads, the resonant off-time is made shorter.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Principle of operation of resonant converters When a resonant circuit is fed with a +10 V step voltage, it oscillates resulting in what is known as ringing. The capacitor charges up to 10 V, at which point current ceases and the capacitor begins to discharge causing current to flow in the opposite direction transferring energy [&hellip;]<br \/><a href=\"http:\/\/machineryequipmentonline.com\/video-equipment\/flat-panel-television-receiversprinciple-of-operation-of-resonant-converters\/\" class=\"more-link\" >Continue reading&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"aioseo_notices":[],"views":709,"_links":{"self":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/150"}],"collection":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/comments?post=150"}],"version-history":[{"count":0,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/150\/revisions"}],"wp:attachment":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/media?parent=150"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/categories?post=150"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/tags?post=150"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}