提高矩阵变换器电压传输比的新型调制策略

电压传输比一直是制约矩阵变换器工业化的一个关键因素．目前还没有具体的调制策略使电压传输比突破0．866．本文提出了一种调制策略,可以使电压传输比超过0．866,最大达到0．955．首先把矩阵变换器的变换过程虚拟为整流和逆变两个环节．整流阶段,采用输入电流空间矢量调制;逆变阶段,采用输出电压空间矢量过调制模式Ⅱ．接着消除中间直流环节,得到直接的交-交变换器．着重对逆变阶段进行了分析,给出了具体的控制算法,并推导出电压传输比的公式．最后进行了实验．结果表明:这种调制策略可以有效地提高电压传输比,具有一定的理论研究价值和应用前景,但增加了谐波,必须采取滤波措施．

New modulation strategy on raising voltage transfer ratio for matrix converts

Voltage transfer ratio is a key element to restrict matrix converter industrialization all the time. The concrete modulation strategy has not been put forward as yet for voltage transfer ratio to break through 0.866.A modulation strategy is put forward to make the voltage transfer ratio excess 0.866 and reach maximum 0.955 in this paper.First Its converting process was imagined into rectifying and inverting links.In rectifying process, the input current space vector modulation was adopted; while in inverting process, the space vector over-modulation mode II was applied to output voltage.Then the direct AC-AC converter was gotten by eliminating the middle direct current link.The inverting process was mainly analyzed.A concrete control algorithm was given and the voltage transfer ratio formula was deduced.Finally, simulation results show that the modulation strategy can raise the voltage transfer ratio of matrix converters, which has some theoretical research values and a good application future; but it increase harmonics. Filtering measures must be taken.