摘要
在谐波阻抗测量领域,投切电容器方法是比较通用的操作方法。在实际电网谐波阻抗测量中由于存在的背景谐波干扰、傅立叶变换过程中的频谱泄漏和采集信号中存在噪声等问题,测量结果将会产生较大误差。为了减小此类影响,采用投切电容器测量电网谐波阻抗的方法并对其进行改进,采取陷波器对信号波形进行预处理从而减小了背景谐波和频谱泄漏的影响;采用小波分析对信号进行重构有效消除了噪声干扰。基于PSCAD和Mat-lab仿真实验,得出比较理想的结果,测量误差大大减小。结果表明,提出的方法有效地减小了谐波阻抗测量误差,在电力系统谐波阻抗测量领域有良好的应用前景。
In the area of the measurement of network harmonic impedance, capacitor switching is a convenient method which is widely used to measure harmonic impedance. On the basis of the transient process of capacitor switching, we presented a method that employed the signal of current and voltage to perform the measurement of harmonic impedance. In addition, because of the disturbance of background harmonics, spectrum leakage and noise, the signal was preprocessed via trap filters, and the noise was eliminated by the wavelet transform. Moreover, case studies based on the simulation with PSCAD and Matlab verified the validity of the proposed method, as well as the potential of its application to the measurement of harmonic impedance.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2009年第7期1780-1784,共5页
High Voltage Engineering
基金
国家"十一五"科技支撑计划重大项目(2006BAA02A21)~~
关键词
谐波阻抗
阻抗测量
电能质量
电容器投切
小波分析
谐波
harmonic impedance
impedance measurement
power quality
capacitor switching
wavelet analysis
harmonics
