基于卡尔曼滤波器校正的改进dq变换的电压凹陷检测方法  

Method for Voltage Sag Detection Based on Modified dq Transformation Corrected by Kalman Filter

作　　者：袁锋[1] 杨洪耕[1] 林呈辉[1] 

机构地区：[1]四川大学电气信息学院,四川成都610065

出　　处：《现代电力》2008年第1期35-39,共5页Modern Electric Power

基　　金：国家自然科学基金资助项目(50677041)

摘　　要：电压凹陷是电能质量的重要问题之一,动态电压恢复器可有效抑制电压凹陷,要求检测算法动态响应速度快。瞬时dq变换法简单、易实现,在动态电压恢复器中应用较多,但低通滤波器降低了瞬时dq变换法的动态响应速度。针对该问题,分析了瞬时dq变换法动态响应过程特点,提出了卡尔曼滤波器校正的改进dq变换法。将动态过程的d轴分量分解为衰减分量和常分量,利用卡尔曼滤波器估计出常分量,并把该分量作为动态过程校正后的d轴分量。d轴变化量大于阈值时启动卡尔曼滤波器;衰减分量小于阈值时退出卡尔曼滤波器。在Matlab6.5中将该方法用于检测多种电压凹陷,结果表明,该方法比传统dq法具有更快的动态响应速度,满足动态电压恢复器的实时性要求。Voltage sag is one of important power quality problems, which can be mitigated efficiently by dynamic voltage restorer （DVR）which requires fast detection method. Dq transformation is applied widely in dynamic voltage restorer（DVR）as it is simple and easy to be implemented, but the low pass filter slows down its dynamic response speed. Aiming at this problem, the dynamic response feature of Dq transformation is analyzed. A modified dq transformation corrected by Kalman filter is presented. The d component is decomposing into decaying component and constant component. Kalman filter is used to estimate constant component as the corrected d component of dynamic process. It＇s suggested to start Kalman filter when d component variation exceeds the threshold and quit Kalman filter when the decaying component is less than the threshold. The proposed method is used to detect several types of voltage sag in the software Matlab6.5. Results show that the method is faster than dq transformation, and meets the real-time request of DVR.

关 键 词：电压凹陷 动态电压恢复器(DVR) dp变换 卡尔曼滤波器 衰减分量 常分量 

分 类 号：TM711[电气工程—电力系统及自动化] TM714