摘要
分布式发电系统并网时,需要实时检测电网电压的基波频率和瞬时相位。该文提出基于强跟踪滤波器的单相电压基波相位实时提取方法:首先添加电网电压基波频率和直流偏移作为状态变量,建立含有直流偏移和谐波分量的单相电网电压信号的非线性状态空间描述;其次,考虑到扩展卡尔曼滤波在系统达到平稳状态时无法快速跟踪系统参数突变,采用强跟踪滤波器递推估计各状态变量,并利用状态变量估计值实时计算单相电压信号的基波频率、幅值和相位。实验结果表明,所提相位实时提取方法能够在消除电网电压直流偏移影响的同时快速跟踪电网参数突变。
Fundamental frequency and instantaneous phase of the grid voltage are the critical information for the operation of the grid-connected power generating systems. A novel strong tracking filter （STF） based real-time extraction method of the single-phase grid voltage fundamental phase was proposed. The grid voltage fundamental frequency and DC offset were added as two of the state variables, and the nonlinear state space description of the single-phase voltage signal contaminated by DC offset and harmonics was established. Considering the extended Kalman filter （EKF） can＇t fast track the system parameters mutation when the system reaches a steady state, STF was introduced to estimate the state variables to get the fundamental frequency, amplitude and phase of the single-phase grid voltage signal in real-time. Experimental results prove the proposed phase real-time extracting method can eliminate the impact of DC offset and fast track the power parameters mutation.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2012年第28期83-89,15,共7页
Proceedings of the CSEE
基金
中央高校基本科研业务费专项资金资助(10CX04036A)~~
关键词
强跟踪滤波器
单相电压
基波频率
瞬时相位
非线性状态空间描述
直流偏移
strong tracking filter
single-phase voltage
fundamental frequency
instantaneous phase
nonlinear statespace description
DC offset
