基于WLSE的不平衡电压下APF谐波电流检测方法  

Harmonic Current Detection Method for APF Under Unbalanced Voltage Condition Using Weighted Least Squares Estimation

作　　者：吴宇[1] 张翠玲[1,2] 李云路[2] 

机构地区：[1]宁夏理工学院继续教育学院,宁夏石嘴山753000 [2]东北大学信息科学与工程学院,辽宁沈阳110819

出　　处：《电气传动》2016年第1期28-32,共5页Electric Drive

基　　金：国家自然科学基金重点资助项目(61433004);国家自然科学基金(51467007)

摘　　要：在三相不平衡的电网电压条件下,存在电压不平衡、甚至伴有频率波动的现象,会引起电压正序分量的相位难以检测,导致有源电力滤波器(APF)的谐波电流检测精度会严重降低。为了解决这一问题,提出了一种针对电压不平衡条件下的谐波电流检测方法。首先利用加权最小二乘估计(WLSE)的方法提升电压正序分量的相位检测精度。然后针对电压频率变化的问题,对电压的频率进行在线估计。最后将该方法与APF谐波电流检测方法相结合,改善检测精度。仿真和实验的结果证明了提出的方法能够在三相不平衡的电压条件下快速准确地检测谐波电流成分。Under the three phase unbalanced voltage condition,the existence of unbalanced voltage even variable frequency make the phase detection of positive sequence voltage more difficult and reduce the accuracy of harmonic detection of active power filter(APF). To solve this problem,proposed a harmonic current detection method under undesirable voltage condition. Firstly,improve the phase detection accuracy of positive sequence voltage using weighted least squares estimation(WLSE). Then,in order to accommodate the variable frequency,estimate the frequency online. At last,using this method combined with harmonic detection method of APF to improve the detection accuracy. The results of simulation and experiment demonstrate that the proposed method can detect the harmonic current component accurately and rapidly.

关 键 词：三相不平衡 有源电力滤波器 谐波电流检测 

分 类 号：TM46[电气工程—电器]