基于Boost变换器的ZVT软开关三相APFC仿真研究

摘要

As the increasingly strict requirements to the power quality of electric grid,they,to increase the input power factor and to reduce the pollution of harmonic currents,have become significant performance index to the inverter type switching power supply.In this paper,the feasibility and superiority of single-phase Active Power Factor Correction (APFC) technology,which being applied in the three-phase rectifier and capacitor filter circuit of the inverter type plasma arc cutting power supply,was theoretically analyzed firstly,and then,the load adaptability of the APFC circuit with Zero Voltage Transition (ZVT) soft-switching was researched on account of the switching loss of power semiconductors in the APFC circuit.The application environment and operational modes of the Boost converter based three-phase APFC circuit with ZVT soft-switching were analyzed in details, pointing out the rationality of adopting discontinuous conduction mode.By using PSpice software,the simulation investigation was carried through to the APFC circuit,giving out the simulation waveforms of voltage and current in supply input and power semiconductors under different output power.The research results show that,the ZVT soft-switching of power semiconductor in the APFC circuit has been achieved in the total load ranges by adopting discontinuous conduction mode,the input power factor of supply can be raised to above 0.94,the waveform of input current is improved effectively and the pollution of harmonic currents is reduced substantially.%随着对电网电能质量的要求日益严格,提高输入功率因数、减少谐波电流污染已成为逆变式开关电源的重要性能指标.首先从理论上分析了将单相有源功率因数校正(APFC)技术应用于逆变式等离子孤切割电源三相整流、电容滤波电路的可行性和优势；然后针对APFC电路的功率器件开关损耗,研究了零压过渡(ZVT)软开关APFC电路的负载适应性.对基于升压变换器(Boost Converer)的ZVT软开关三相APFC电路的应用环境和工作模态进行了详细分析,指出采用非连续导通模式的合理性.采用PSpice软件对APFC电路进行了仿真研究,给出了不同输出功率下的电源输入和功率器件的电压电流仿真波形.研究结果表明,采用非连续导通模式的APFC电路可实现全负载范围的功率器件ZVT软开关,电源系统的输入功率因数可提高至0.94以上,有效改善了输入电流波形,谐波电流污染大幅降低.