基于频率自适应的双二阶巴特沃斯数字滤波方法  

Digital Biquadratic Butterworth Filter Method Based on Frequency Self-adaptation

作　　者：郭燕[1] 曾光[1] 杨波[1] GUO Yan ZENG Guang YANG Bo(Department of Electrical Engineering, Xi＇an University of Technology, Xi＇an 710048, Shaanxi Province, China)

机构地区：[1]西安理工大学电气工程系,陕西省西安市710048

出　　处：《智能电网》2016年第12期1204-1209,共6页Smart Grid

摘　　要：频率波动、谐波未知的畸变电网导致相位和频率检测存在稳态误差,从而影响滤波器的滤波性能。针对上述问题,提出一种基于频率自适应的双二阶巴特沃斯数字滤波方法,该方法采用两个双二阶巴特沃斯带通滤波器,可实时检测电网电压的相位和频率并提取基波信号;分析巴特沃斯带通滤波器的特性及频率自适应滤波算法的结构;阐述该频率自适应滤波算法在电压锁相环和特定次谐波检测中的应用。仿真与实验结果验证了基于频率自适应的双二阶巴特沃斯数字滤波方法的有效性。该方法能够精确检测电网电压的相位和频率,并能有效消除因电网频率波动、电网畸变而导致的相位和频率检测误差,而且适用于单相或三相系统。Distorted grid with frequency fluctuation and unknown harmonic causes steady-state error in phase and frequency detection, which affects performance of the filter. To solve these problems, a digital biquadratic Butterworth filter method based on frequency self-adaptation is proposed. This design uses two biquadratic Butterworth band-pass filters to real-time detect phase and frequency of the grid voltage and extract fundamental component. The characteristics of Butterworth band-pass filter and the structure of frequency self-adaptive filtering algorithm are analyzed. The application of the algorithm in voltage phase-locked loop and specific harmonic detection is introduced. The simulation and experimental result show that the digital biquadratic butterworth filter method based on frequency self-adaptation is effective. The method can accurately detect the phase and frequency of the grid voltage and effectively eliminate detection error caused by frequency fluctuations and distortion of the grid. It works in single-phase or three-phase system.

关 键 词：巴特沃斯带通滤波器 频率自适应 基波提取 锁相环 特定次谐波检测 

分 类 号：TM935[电气工程—电力电子与电力传动]