矩阵变换器的一种安全换流策略

矩阵变换器由于换流困难始终无法在大功率环境中得到推广应用，该文在传统的电压型两步换流法的基础上，提出一种过渡区间采用四步换流的安全换流策略，在电压接近的换流两相之间插入3个安全续流状态来实现换流，避免了电流型换流法小电流检测困难的问题，解决了原来换流法换区间时容易短路的现象，完善了电压型换流策略。该策略不仅对输入输出波形影响较小，而且实现较为简单，系统开关损耗也不会增长很多。全压380 V输入和5 kW功率输出实验结果表明，该换流策略是可行的。提出的新型换流策略可在大功率交-交电力变换中得到进一步推广和应用。

Safe Commutation Strategies for Matrix Converter

Commutation problem is one of the reasons why matrix converter has not been used in high-power conditions. To avoid zero crossing problem of the current-controlled commutation, four-step safe commutation strategy in transition intervals was proposed based on traditional voltage- controlled commutation. Three free wheeling states were used between two adjacent input voltages to realize safe commutation. The voltage-controlled commutation was consummated and the short-circuit phenomenon during changing intervals was solved. The strategy has many advantages such as little influence on input and output waveform, easy to realize and low additive switching loss. Experimental results of 380 V voltage input and 5 kW power output verified that the new method is valid and feasible. The commutation scheme can find broad applications in high-power AC-AC matrix converters.