一种新型级联多电平逆变器SHEPWM控制技术

A Novel SHEPWM Control Technique for Cascaded Multilevel Inverter

传统级联型多电平逆变器特定谐波消除脉宽调制(SHEPWM)技术只适用于各单元直流侧电源完全相等的情况,但在实际应用中电源电压可能会产生一定的偏差,这使得SHEPWM消谐效果变差。此处提出了一种直流侧电源电压不相等的多电平逆变器SHEPWM技术,并利用多种群遗传算法(MPGA)求解所建立的非线性方程组,得出了开关角度轨迹,且确定了性能最优的一组解,通过仿真和实验研究验证了理论的正确性。

Traditional selective harmonic elimination pulse width modulation （SHEPWM） technology of cascaded mult- ilevel inverter is only applicable to the direct current power supply completely equal, but the power in the practical application of voltage may cause a certain deviation which makes the SHEPWM harmonic elimination effect of varia- tion.A new SHEPWM technique is presented for the multilevel inverter which direct current power is not equal.By using multiple population genetic algorithm（MPGA）,the established nonlinear equations are solved and the switch an- gle trajectories under are researched and a set of solutions for optimal performance is identified.Through the simula- tion and experimental results, the correctness of the theory is verified.