多电平逆变器准最优脉宽调制方法

Improving Multilevel Inverter with a New Suboptimal PWM (Pulse Width Modulation) Algorithm

多电平变换器是高压大功率应用领域的研究热点,文中针对多电平载波PWM技术中电压调制深度低和基波幅值小的问题,提出了一种新颖的多电平准最优PWM法,分析了输出最大电压调制深度、基波幅值和谐波畸变率等,同时给出了输出电压开关切换角、最优调制波形等的求解方法,并进行了计算机仿真。结果表明,该方法极大地提高了输出电压调制深度和基波幅值。

The full paper starts with discussing in some detail what appeared to us to be the deficiencies of xisting PWM algorithms. We then propose a new suboptimal PWM algorithm that can, in our pinion, improve the performance of multilevel inverter. The proposed suboptimal algorithm can increase onsiderably the voltage modulation index and fundamental component. In the full paper, we describe in etail the proposed suboptimal algorithm; here we just list the two topics discussed： （1） the consideration n some detail of the calculation of optimal modulation wave form; （2） the consideration in much detail of he calculation of the suboptimal PWM wave form or switching angles. Simulation results do show preliminarily that the proposed suboptimal algorithm can increase the voltage modulation index and undamental component considerably. Besides, simulation results also show that total harmonic distortion can be decreased somewhat with our proposed suboptimal algorithm.