基于近似熵和混沌振子的电力谐波检测与估计

Detection and estimation of the harmonics in power system based on approximate entropy and chaotic oscillator

将近似熵测度与基于混沌振子的信号检测方法相结合,以解决电力系统谐波检测与估计领域现存的技术难题。通过理论分析和仿真研究,证明了适应步长型间歇混沌振子的系统输出近似熵值,只与待测信号的频率有关,而且不同相态下的系统输出近似熵值具有明显差异,进而提出了一种采用近似熵测度的适应步长型间歇混沌振子,并说明了此方法对电力系统谐波、间谐波检测和频率估计的适用性。在此基础上,还对一种基于Duffing系统的正弦信号幅值和相位同步估计方法进行了改进,降低了原方法的复杂度并提高了实时性,并用以实现对谐波和间谐波的幅值、相位同步高精度估计。

In order to solve the current technology problems of harmonics detection and estimation in the field of power system,this paper attempts to combine the approximate entropy measurement and the chaotic oscillator firstly. Based on the theoretical analysis and the simulation research,this paper proved that the output approximate entropy of the adaptive-step-length intermittent chaotic oscillator is just relevant to the frequency of the signals to be detected. For the approximate entropy had oblivious differences under different conditions,this paper proposed the intermittent chaotic oscillator with the approximate entropy measurement,and described the applicability of this new method to the harmonics detection. Besides,this paper improved a synchronization estimation method of the amplitude and phase of sine signals based on Duffing system,which made the method complexity lower and the real-time performance better,and the high accuracy estimation of amplitude and phase synchronization was realized.