带多频段采样观测器的单相逆变器控制  

A Single-phase Inverter Control With Multi-band Sampling Observers

作　　者：闫士杰[1] 纪茂新[1] 黄丽萍[1] 杨惠惠[1] 

机构地区：[1]东北大学信息科学与工程学院,辽宁省沈阳市110819

出　　处：《中国电机工程学报》2013年第12期81-89,189,共9页Proceedings of the CSEE

基　　金：辽宁省自然科学基金(20102068)~~

摘　　要：在单相逆变器控制系统中,当逆变器带非线性负载时,输出电压波形会出现畸变,存在幅值和相角误差。为解决上述问题,提出一种基于电流观测器的单相逆变器控制策略。首先应用傅里叶变换提取逆变器输出的基波电压,然后通过幅相分解,将逆变器输出电压等效变换为电压幅值与相角,最后应用PI控制器控制逆变器输出电压波形为正弦波。控制系统实现时,采用前馈控制方法,来抑制谐波,提高逆变器输出波形质量。为解决因采样频率低而带来的逆变器输出电流估算精度下降的问题,在前馈控制时,采用多频段采样法来对电流谐波进行估算,从而提高了前馈控制的精度,进一步提高了逆变器输出波形质量。仿真和实验结果表明了该控制策略的正确性和实用性。In the single-phase inverter control system, when the load was nonlinear, the output voltage waveform of inverter would be distorted. At the same time, the amplitude error and the phase angle error would be appeared. In order to solve these problems above, a control strategy based on current observers for single-phase inverter was proposed. Firstly, the harmonics were eliminated and the fundamental frequency voltage was extracted by the application of Fourier transform. Then the output voltage of inverter was equivalent transformed into amplitude and phase angle by amplitude-phase decomposition. Finally, controlled by PI controllers, the output voltage of inverter was sinusoidal wave. When the control system was carried out, the feed-forward control method was used to eliminate the harmonics and improve the quality of inverter output waveform. As the low sampling frequency for inverter output current would lead to estimation accuracy declining, a multi-band sampling method was used to estimate current harmonics. Therefore, the accuracy of feed-forward control can be improved and the quality of the inverter output waveform can be improved further. The results of simulation and experiment are shown that the control strategy is correct and practical.

关 键 词：单相逆变器 电流观测器 幅相控制 谐波补偿 多频段采样 

分 类 号：TM461[电气工程—电器]