基于准谐振型软开关的高频开关电源变换器

摘要

The tradition high-frequency switching power supply transfer circuit uses the hard-switch technology, whose the circuit power consumption is great, the withstanding voltage and the current stress are high. In order to overcome the hard switch technology negative factors caused by the forced shutoff when electric current goes through the switching valve and the forced breakover when the switching valve has voltage, the quasi-resonance soft switch technology is adopted, namely zero current switch (ZCS) quasi-resonant converter and zero voltage switch (ZVS) quasi-resonance converter. The resonant loop is composed of the inductance and electric capacity. It allows the breakover when the switching valve is at zero voltage or the shutoff when the the switching valve is at zero current by the aid of the energy exchange between the inductance, electric capacity to achieve the reduction of switching power consumption and the electromagnetic interference. The soft switch technology is widely used in new switching power supply.%传统高频开关电源变换电路采用硬开关技术,电路功耗大,承受电压、电流应力高.为了克服硬开关技术中开关管在有电流通过的情况下被强制关断,有电压情况下被强制导通而带来的各种不利因素,采用准谐振型软开关技术,即零电流开关(ZCS)准谐振变换器、零电压开关(ZVS)准谐振变换器,由电感、电容组成谐振回路,利用电感、电容之间的能量交换,使主开关管在零电压下导通或零电流下截止,达到了减少开关损耗及电磁干扰的目的.软开关技术在新型开关电源中广泛采用.