This article proposes an approach to mitigate the dc-link double-frequency ripple current in a three-leg single-phase to three-phase converter. This article is based on an economical active phase converter (APC) utilizing a fewer number of switches. The presented approach does not demand either bulky dc side passive ripple filter or additional semiconductor switches typically employed in active dc-link ripple filters. The proposed method introduces an appropriately selected ac capacitor into the APC circuit, also known as auxiliary capacitor-based APC, which mitigates the dc-link double-frequency ripple. Reduction of power loss in the equivalent series resistor of the dc-bus capacitor associated with the dc-link double-frequency ripple current enhances the lifetime of electrolytic capacitor typically employed in the APC. At full load, the dc-link current at double-fundamental frequency is reduced by more than 50% and the temperature rise in the dc-bus electrolytic capacitors is reduced by more than 30%. The proposed method is validated experimentally using a laboratory prototype APC. Theoretical and simulation results of the dc-link double-frequency current are in close agreement with the experimental findings.

中文翻译：

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减少开关数量的单相至三相转换器中的低频直流母线电容器电流缓解


本文提出了一种减轻三桥臂单相至三相转换器中直流链路双频纹波电流的方法。本文基于使用较少数量开关的经济型有源相位转换器 (APC)。所提出的方法不需要笨重的直流侧无源纹波滤波器或通常在有源直流链路纹波滤波器中使用的额外半导体开关。所提出的方法将适当选择的交流电容器引入到APC电路中，也称为基于辅助电容器的APC，其减轻了直流链路双频纹波。与直流链路双频纹波电流相关的直流母线电容器的等效串联电阻器中的功率损耗的减少提高了通常在APC中使用的电解电容器的寿命。满负载时，双基频下的直流母线电流降低了50%以上，直流母线电解电容器的温升降低了30%以上。使用实验室原型 APC 对所提出的方法进行了实验验证。直流母线双频电流的理论和仿真结果与实验结果非常吻合。