Research On The Application Of TLS-ESPRIT Algorithm To Signals Parameters Extracting In Power System

On the basis of a novel signal processing method called total least square estimating,this paper studied the measurement of dielectric loss angleδ,the parameters identification of Synchronous Machine and the voltage flicker parameter extracting.In sum,the researches in this paper are as follows:1.As the previous measurement algorithm of dielectric loss angle is complex and could not get the high accuracy,this paper infers a new method for Calculation of the dielectric loss angleδ-TLS-ESPRIT,which divides signal matrix into signal subspace and noise subspace.This method posses extracting fundamental component and denoising,which achieves high precision in extracting the initial phase of the operating voltage and leakage current.The simulation test shows that this method immunes to changing power system frequency,harmonics component and the changingδ.TLS-ESPRIT is a higher precision calculating method than the method of sine-wave parameters and the method of sine based on wavelet in dielectric loss angle measuring.2.According to the characteristics of three-phase short-circuit current signal, TLS-ESPRIT is applied in parameter identification of synchronous machine.This method decomposes HANKEL matrix which is formed by short-circuit current into signal subspace and noise subspace and is processed by TLS(total least square),so it is a high precision method and improves the capacity of anti-noise.It can extract the transient and sub-transient parameters of synchronous machine accurately.The simulation example demonstrates that this method is capable of having higher precision,stronger anti-noise capacity and easier than other identification method such as prony and prony based on wavelet.The dynamic simulation test proves that this method is available and feasible.3.The voltage flicker signal of low-amplitude single frequency and multi-frequency superposition modulated is decomposed,which is expressed as sum of a series of side-frequency and fundamental wave.This paper infers the method of TLS-ESPRIT in obtaining the parameters of side-frequency as amplitude,angle and frequency.By calculating,the parameters of voltage flicker is gotten.This paper infers a new method for the parameter extracting of voltage flicker.