软斩波功率控制IGBT四倍频300 kHz/50 kW焊接电源

提出了一种IGBT四倍频分时控制300kHz大功率感应焊接电源．功率调节由三相桥式不控整流电路和直流斩波电路组成，斩波电路采用有源无损缓冲Buck变换器，在较宽的负载范围内使主、副开关管和续流二极管均实现软开关．采州四组IGBT并联的逆变器，对每个IGBT进行分时控制，逆变器的工作频率是IGBT开关频率的四倍．逆变器工作在负载谐振状态，开关管工作在零电流开通和零电压关断的条件下．设计了输出300kHz／50kW的串联谐振感应焊接电源，给出了设计参数和试验波形．结果表明．采用四倍频分时控制的方法，用IGBT替代功率MOSFET制作高频大容量感应加热焊接电源成为可能．

Soft-switch DC chopper four fold-frequency power control 300 KHz/50 kW induction welding power

A four times frequency IGBT 300KHz induction welding power is put forward.Power control is composed with three-phase diode bridge inverter and DC chopper circuit.The chopper circuit adopts active nondestructive buffer buck converter, and in a wider range of the load the main, deputy switch tube and free-wheeling diode are achieve soft switch.The four groups of IGBT inverter in parallel are used for each IGBT in time-sharing control.The work frequency of the inverter is four times of the frequency IGBT switch.The inverter works in the load resonant state, and the switch tube works in shutting off at ZCS and switching on and off at ZVS.The output 300 kHz/50 kW serial-resonant inductive welding power was designed, and the design parameters and test waveforms were given.The results show that it is possible to produce capacity of high frequency induction heat welding power by using the method of four-times frequency control points with IGBT alternative power MOSFET.