電圧形PWM変換器のデッドタイムに起因する電圧誤差補償法の系統連系時の動作特性

抄録

This paper discusses the performance of compensation methods for dead-time voltage error in voltage-source grid-connection PWM converters. The theoretical analysis in this paper reveals the relationship between the voltage error and the current ripples through the converter. The analytical results imply that the voltage error is strongly affected by the amplitude of the current ripples as well as the source power factor. This paper proposes a new compensation method which makes it possible to use two lookup tables to reduce the calculation time in the controller. The compensation characteristics are compared by using a 200-V 5-kW three-phase grid-connection converter. As a result, conventional approximation-based compensation methods exhibit an acceptable performance in a restricted power-factor operation range. In contrast, the turn-off transition-based compensation method and the proposed method have a good compensation performance all over the power-factor.