摘要
为了提高非线性方程组的求解速度,提出了一种基于"冲量相等、重心重合"原则和直接数值计算的非线性方程组初值求取方法。以12个开关切换点为例,主要研究了五电平逆变器SHEPWM非线性方程组在调制比从1.15到0.01的全范围变化时的求解方法,对每一个M值给出了至少一组数值解。求解过程证明所提初值方法是有效的。论文讨论了随着M值从大到小变化,SHEPWM问题的解及其代表的波形的变化趋势。对选取的典型数值解进行了仿真和实验研究,结果证明所得数值解能够实现基波控制目标并有效消除选定的低频次谐波。
In order to enhance the convergent speed, a method based on equality of area and superposition of barycenter of the PWM section with the sine-reference signal for obtaining initial values is proposed. The SHEPWM non-linear equations of five-level voltage inverters for full range modulation index M are solved and at least one group of solutions is obtained for each M with a step of 0.01. Solving process of the equations proved that the initial values are very effective. The numbers of switching angle between different output levels vary with M values. Based on PSIM6 software and a five-level cascade inverter prototype, two solutions for M equal to 0.5 are investigated by simulation and experiment. The result proved the conclusions reached.
出处
《电工技术学报》
EI
CSCD
北大核心
2009年第2期85-93,99,共10页
Transactions of China Electrotechnical Society
基金
江苏省高等学校自然科学基础研究(07KJB470056)
中国博士后科研基金(20060400934)资助项目
关键词
五电平逆变器
特定谐波消除
脉宽调制
调制度
Five-level inverter, selected harmonic elimination, PWM, modulation index
