交-交变频器谐波消除方法的探讨

随着电力电子技术的发展,交-交变频器的应用愈加广泛。在交-交变频器输出的电压波形中含有大量的谐波,为有效地消除谐波的不利影响,采用余弦交点法控制的交-交变频器,通过对输出电压波形的基本结构进行分析,找出谐波的内在规律,提出了谐波同步消除方法,谐波同步消除方法属于有源滤波,利用其特有的谐波分析方法控制谐波电源的输出补偿电压,补偿电压与谐波同时产生,相位相反,从而达到滤波的目的。与现有的其它方法相比,其算法简单、效果明显,更加适用于输出电压频率频繁变化的场合,即使在变频器直流输出时,也可达到明显的滤波效果。

Research on the Filtering Method of Cycloconverter

With the development of power electronics,cycloconverter has been adopted in many fields.There are many harmonics in the output voltage of cycloconverter,so how to reduce the adverse influences of harmonic voltage is an important problem for researchers.In this paper,the configuration of the output voltage-wave of cycloconverter is analyzed,and the intrinsic regulation of harmonic voltage-wave is found.Based on this analysis,a new filter method named synchronous filter method is presented.Synchronous filter method is an active power filter,it controls the output compensating voltage of harmonic voltage source by its special harmonic analysis method.In order to filter the output voltage of cycloconverter,compensating voltage and harmonic voltage are outputted at the same time,and counteracted because their phases are opposite.Compared with other active power filters,synchronous filter method has the characteristics of simple calculation and obvious effect.This method is adapted to the situation that the output frequency is changed continually and even the output of cycloconverter is DC voltage.