基于Walsh变换的特定谐波消除脉宽调制技术在动态电压恢复器中的应用  

Application of Selective Harmonic Elimination PWM Technique Based on Walsh Transform in DVR

作　　者：赵艳雷[1] 何飚[1] 童建忠[1] 

机构地区：[1]中国科学院电工研究所,北京市海淀区100080

出　　处：《电网技术》2006年第10期45-49,共5页Power System Technology

摘　　要：基于Walsh变换的特定消谐PWM(selective harmonic elimination PWM,SHEPWM)方法把其对应的Fourier域内的超越非线性方程转化为线性代数方程,在合适的初始条件下,能得到基波幅值和开关角的分段线性关系,从而可实现在线调压和谐波抑制,特别适用于动态电压恢复器(dynamic voltage restorer,DVR)逆变器的控制。本文介绍了Walsh函数,分析了Walsh域SHE线性方程的建立和求解过程,提出了以质心PWM技术产生初始开关角分布模式的方法,有效提高了计算效率,并且针对SHEPWM脉冲的谐波分布特点,给出了逆变器的滤波器设计原则和方法。在200 kVA 级DVR上的实验结果表明,逆变器在整个电压范围内能有效抑制各次谐波并有良好的动态特性,证实了该方法的可行性和有效性。The SHEPWM （selective harmonic elimination PWM） technique based on Walsh transform converters nonlinear transcendental equations in the Fourier domain to linear algebraic ones. Under appropriate initial condition, the piecewise linear relation between voltage fundamental amplitude and switching angles is obtained, so voltage regulation and harmonic elimination can be realized online. Thus, the technique highly suits to the control of DVR （dynamic voltage restorer） inverter. The paper introduces Walsh function, production and solving of linear SHEPWM equations in Waish domain. A new initialization method is proposed that uses CPWM （centroid PWM） and can improve computation efficiency. According to the feature of harmonic distribution of the SHEPWM pulses, the paper presents design principle of inverter filter. The experimental result of 200kVA DVR, which indicates that the inverter can effectively restrain all the harmonics and has good dynamic performance in all the range of output voltage, proves feasibility and validity of the technique.

关 键 词：逆变器 动态电压恢复器(DVR) 特定谐波消除 WALSH函数 质心PWM(CPWM) 

分 类 号：TM761[电气工程—电力系统及自动化]