矩阵变换器间接空间矢量逆变级过调制策略优化设计

Optimal design of indirect space-vector over-modulation strategy for inverter stage of matrix converter

为克服传统多轨迹矢量加权过调制策略中输出电压误差大和谐波含量高的缺点,提出一种新的过调制策略,该策略在过调制Ⅰ区和Ⅱ区分别减小了六边形矢量和基本矢量在参考电压矢量中的权重。通过对改进前后过调制策略的输出电压基波幅值和输出电压谐波畸变率进行理论分析,得出改进后过调制策略可以获得更小的输出电压误差和谐波含量。对改进前后过调制策略用于矩阵变换器的输出性能进行仿真研究和实验验证,结果表明所提策略有效减小了输出电压期望值与实际值之间的误差和输出电压谐波含量,验证了理论分析的正确性和所提策略的可行性。

An improved over-modulation strategy is proposed to avoid the big output voltage error and high THD（ Total Harmonic Distortion） of traditional multi- orbit vector weighted over-modulation strategy,which respectively reduces the weights of the hexagon vector and basic vector in the reference voltage vector for over-modulation Region Ⅰ and Region Ⅱ. The theoretic analysis on the fundamental amplitude and THD of the output voltages by the traditional and proposed over-modulation strategies shows that the output voltage error and THD by the proposed strategy are smaller. The output performance of matrix converter is simulated and tested with the traditional and proposed over-modulation strategies respectively and results show that,the proposed strategy effectively reduces the difference between expected and real output voltages and the output voltage THD,verifying the correctness of theoretical analysis and the feasibility of the proposed strategy.