矩阵式双向变流器改进型换流策略

Improved commutation strategy for bidirectional converter based on matrix converter

针对基于矩阵式变换器的双向变流器电压电流型一步换流策略进行研究。通过分析电压电流型一步换流中存在的问题,指出其在输入相电压相对大小判断不准确时会使得输入电流波形畸变,并提出了基于过渡区间两步换流的改进型换流策略。通过在输入相电压大小相近时设置合适宽度的过渡区间,在过渡区间内采用两步换流,在过渡区间外采用一步换流,从而有效地避免了电压扇区判断错误的情况。最后通过仿真模型和实验样机,对所提出的改进型换流策略的有效性和正确性进行了仿真和实验验证,结果证明所提换流策略能准确地判断电压扇区所在空间,改善输入电流波形。

The current-vohage one-step commutation strategy for bidireetional converter based on matrix converter is researched. The existing problems of current-voltage one-step commutation are analyzed and it is pointed out that,the inaccurate judgment of input relative voltage will distort the input current waveform. An improved commutation strategy based on ＂two-step commutation within intermediate interval＂ is proposed, which sets an intermediate interval with appropriate width when the input voltages are similar and adopts the two-step commutation within the interval while keeps the one-step commutation outside the interval, effectively avoiding the voltage sector judgment error. The effectiveness and correctness of the proposed commutation strategy are verified by simulation and experiment,which shows thai,the voltage space sector is accurately determined and the input current waveform is improved.