低共模残压的改进型两电平四桥臂AZSPWM1方法OA

In flexible interconnection systems of distribution networks,common-mode voltage generated by power electronic converters may lead to a series of adverse issues such as leakage currents.The reduced common-mode voltage pulse width modulation(RCMV-PWM)techniques are widely studied and emphasized to deal with the problem.In four-wire systems,two-level four-leg RCMV-PWM often involves simultaneous switching actions of two different bridge arms.In such cases,the dead-time effect of interlocked switching devices may introduce undesired common-mode voltage spikes,increasing residual common-mode voltage and weakening the suppression effect.This paper proposes a modified active-zero-state PWM(AZSPWM)method based on current prediction and active disturbance dead-time compensation,which effectively reduces residual common-mode voltage and improves power quality.The paper presents a prediction method for the converter output current,achieving dead-time compensation by adjusting the amplitude of the modulation wave.Furthermore,to address the inaccuracy of current direction prediction near zero-crossing points,this paper introduces an active disturbance control method to regulate the current direction and enhance prediction accuracy.Simulation and experimental results verify the effectiveness of the proposed method.