摘要
提出一种采用无损有源箝位辅助电路的移相脉宽调制(phase shifted pulse width modulation,PSPWM)高频链DC-AC变换器。相比于当前的两级逆变技术,该变换器实现了单级功率变换,省去了两级逆变器中的DC-DC变换器,减小了变换器复杂度。该变换器采用双极性PSPWM调制,输出电压的总谐波失真(total harmonic distortion,THD)较低。在目前技术中,双向开关管在双极性调制下较难实现软开关。提出一种无损有源箝位电路,箝位变压器和双向开关管两端电压,实现了双向开关管的软开关,提高了变换器效率。分析该变换器的调制方法、工作模态及变换器软开关过程,通过搭建一台200W的实验样机,验证理论分析的正确性。实验结果显示,提出的变换器的峰值效率可达92.25%,输出电压THD在0.02~20k Hz宽范围内均低于0.22%。
A soft switching phase-shifted pulse-width modulation（PSPWM） high-frequency-link（HFL） DC-AC converter with auxiliary lossless active clamping circuit was proposed. Compared with two-stage DC-AC converter, the proposed DC-AC converter is single stage power conversion, omitting the DC-DC converter in two-stage DC-AC converter, reducing the complexity of the DC-AC converter. The output voltage total harmonic distortion（THD） of the proposed converter was lower by applying bipolar PSPWM. But it is difficult to achieve soft switching of bidirectional switches with bipolar PSPWM. A novel auxiliary active clamping circuit was proposed, clamping the spike voltage across transformer and bidirectional switches, making the bidirectional switches achieve soft switching, which greatly improves efficiency of the proposed DC-AC converter. In addition, experimental results of a 200 W prototype were presented to verify the analysis results of the proposed DC-AC converter. According to the experimental result, peak efficiency as 92.25% and ultralow output voltage THD below 0.22% are achieved.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2017年第4期1197-1207,共11页
Proceedings of the CSEE
关键词
高频链变换器
单级功率传输
软开关
低输出失真
有源箝位
high-frequency-link converter
single stage power conversion
soft switching
ultralow output distortion
active clamp
