图腾柱无桥PFC输入电压检测与仿真研究

Detection and Simulation of Input Voltage of Totem-Pole Bridgeless PFC

针对无桥PFC无"整流桥"存在,导致PFC控制电路所需的全波整流电压检测困难等问题,提出了一种低频整流桥加电压隔离放大器方式的适用于图腾柱无桥PFC的解决方案。电压隔离放大器将整流分压后得到的全波整流电压隔离传输至PFC控制输入端,有效阻断了输入电压检测电路与主电路之间相互干扰,解决了无"整流桥"输入电压检测问题。最后,通过PSIM仿真软件对所提方案进行仿真验证。仿真结果表明,所提方案能够较好地实现图腾柱无桥PFC输入电压检测作用,仿真得到的谐波含量较低,功率因数较高。

In order to solve the problem that the bridgeless PFC without “rectifier bridge” leads to the difficulty of detecting full-wave rectifier voltage in PFC control circuit,a solution of low-frequency rectifier bridge plus voltage isolation amplifier was proposed,which is suitable for totem-pole bridgeless PFC.The voltage isolation amplifier transmits the full wave rectified voltage isolated from rectifier to PFC control input,which effectively blocked the interference between the input voltage detection circuit and the main circuit,and solved the problem of detecting input voltage without “rectifier bridge”.Finally,the proposed scheme was verified by PSIM simulation software.The simulation results show that the proposed scheme can better detect the PFC input voltage of totem-pole bridgeless PFC,and has lower harmonic content and higher power factor.