可减小开关损耗的双级矩阵变换器调制策略

Modulation Strategy of Two-stage Matrix Converter with Reduced Switching Loss

提出了一种以降低整流级开关器件损耗为优化目标的双级矩阵变换器无零矢量调制策略,通过合理安排区间切换时的整流级输出直流电压,在不改变传统调制策略的合成电压矢量的前提下,降低了双级矩阵变换器的整流级开关频率,减小了开关损耗,提高了装置效率。从理论上进行了损耗分析,结果表明该调制策略可获得明显的装置效率提高。与双级矩阵变换器传统无零矢量调制策略的对比研究表明优化后的调制策略不仅能够降低开关损耗,同时在开关频率较低的应用场合输出线电压的总谐波畸变得到改善,提高了输出波形质量。

A modulation strategy without zero space vectors for the rectifier stage of two-stage matrix converterswas proposed,its optimization goal was to reduce the power loss of the rectifier stage. By reasonably arranging the DCvoltages of the rectifier outputs during the sector switching intervals,without changing the voltage vector synthesis oftraditional modulation strategy of the rectifier stage,the switching frequency of the two-stage matrix converter wasreduced and hence the switching loss was reduced,and the equipment efficiency was improved eventually. Thetheoretical loss analysis was carried out,the results show that the equipment efficiency is significantly improved whenthe proposed modulation strategy was employed. Comparative study with the traditional no zero space vector modulationstrategy of two-stage matrix converters shows that the proposed optimized modulation strategy can not only reduce theswitching losses,while the total harmonic distortion of the output line voltages are improved in the low switchingfrequency applications,the quality of the output waveforms are enhanced.