实际应用中的矩阵变换器空间矢量调制算法及优化调制模式

Optimization Modulation Pattern for Space Vector Modulation Method of Matrix Converter in Practical Application

矩阵变换器在实际应用中会出现非理想状况,空间矢量调制策略算法不恰当会引起输出波形畸变。考虑输入非正常工况和换流时间问题,提出空间矢量调制策略的实现算法和优化的调制模式,以获得宽调节范围、低谐波的输出性能。首先提出一种采用矢量幅值之比实时计算电压调制比的方法,实现矩阵变换器在输入电压正常和非正常工况下均能输出三相正弦对称电压的目的;然后分析7种调制模式在考虑换流时间情况下窄脉冲出现的几率,在此基础上提出优化的调制模式,以解决窄脉冲引起的输出波形畸变问题;最后,设计一套基于数字信号处理器和现场可编程门阵列的控制系统,实现所提算法。实验结果验证了该实用算法的正确性。

The traditional space vector modulation（SVM） method will cause the output voltage distortion of the matrix converter when it works under non-ideal conditions with considering the problems for practical use.Considering abnormal supply conditions and commutation time,an improved SVM algorithm and optimized modulation pattern for a practical matrix converter were presented to achieve the wide regulation range of the output voltages with few harmonics.First,a novel modulation method was presented by using the instantaneous vector magnitude of output voltage and input voltages to calculate voltage modulation index.The matrix converter could produce three-phase sinusoidal symmetrical voltage under normal and abnormal input voltage conditions with this method.Second,the probability of narrow pulses in seven modulation patterns was analyzed considering commutation time.Then an optimized modulation pattern was proposed to solve the problem of distorted the output voltages caused by the narrow pulses.Finally,a matrix converter prototype based on digital signal processor（DSP） and field programmable gate array（FPGA） had been built.Experimental results prove the validity of the practical strategy proposed in the paper.