【摘要】 近年来,电能质量扰动信号的检测已成为国内外研究的一个热点。就振荡瞬变与电压波动这两种电能质量现象提出了新的检测方法。对于振荡瞬变现象,现有的方法往往只能实现扰动定位检测,难以提供振荡频率、幅值、持续时间等必要特性参数。提出了基于小波变换和Prony算法的检测方法,利用小波奇异性检测特性实现扰动定位检测,同时还利用Prony算法直接求取其特征参数。对于电压波动,IEC推荐的闪变仪不适合分析时变的或含多种调制频率的波动信号,并且只能提供基于统计评价的闪变值。提出的基于小波变换的检测方法,利用小波奇异性检测特性检测出波动的起止时刻;利用小波多分辨分析理论测量出波动分量含有的各调制频率及对应幅值,最后计算出闪变值。基于Matlab和Simulink/PSB软件的仿真结果都表明了提出的两种检测方法的有效性。更多还原

【Abstract】 In recent years,the detection of disturbance signal in power quality has become a research hotspot.In this paper,two new detection methods are proposed to detect the transient oscillation and the voltage fluctuation.The existing methods can only detect the occurring time of disturbance.Some necessary parameters such as oscillation frequency,amplitude and duration time can not be detected.The proposed detection method based on wavelet transform and Prony algorithm can detect the occurring time with the theory of wavelet singularity detection and also work out the parameters directly with the application of Prony algorithm at the same time.The flicker meter recommended by the IEC is not suitable for the analysis of time-variant fluctuation signal or that with multiplicate demodulation frequencies.And it can only provide the flicker value based on statistical evaluation.In this paper,the proposed detection method based on wavelet transform can detect the start and end time of fluctuation with the theory of wavelet singularity detection.It can also measure the frequency and amplitude of the component fluctuating signal with the theory of multi-resolution analysis.The accurate flicker value is finally got.The simulation results Matlab and Simulink/PSB software show the effectiveness of the two proposed detection methods.更多还原