Research On Harmonic Responsibility Sharing Method Based On Orthogonal Signal Correction And Partial Least Squares

With the rapid development of the smart grid,the proportion of nonlinear load in the power system has increased significantly.Especially after the thyristor rectification and frequency conversion devices are more and more widely used in the industry,the nonlinear load in the power supply system is greatly increased.Injecting a large number of high-order harmonics into the power grid,causing severe harmonic current injection at the common connection point(PCC),and forming harmonic voltages to distort the supply voltage waveform,and the power quality is degraded,giving other connections to the same grid system.Electrical equipment brings adverse effects and hazards.In order to effectively suppress the harmonics of the power grid,the sharing of harmonic responsibilities must be quantified.Encourage and promote the control of harmonic pollution according to the harmonic responsibility of each subject.At present,the study of harmonic responsibility sharing quantification is mainly based on the accurate calculation of harmonic impedance.There are two main methods,namely"intrusive" and "non-intrusive".Since "non-intrusive" directly uses measured harmonic data without changing the operating state of the power system,it has gradually become the main research direction for quantifying harmonic responsibility.Firstly,the paper summarizes the hazards of harmonics,and introduces the basic duties of power companies and power consumers to the harmonic management of power grids.Then it summarizes the existing methods of harmonic responsibility sharing and analyzes its advantages and disadvantages.Aiming at the problems existing in the current harmonic responsibility sharing method,this paper proposes a harmonic responsibility sharing method based on orthogonal signal correction and partial least squares method.Firstly,the orthogonal signal correction method is used to preprocess the measured PCC point harmonic voltage and harmonic current values,and the orthogonal data information irrelevant to the harmonic impedance calculation in the harmonic voltage and harmonic current measurement data is eliminated;The influence of background harmonics and noise in the system eliminates the interference of abnormal data in the measured data,and solves the system and user harmonic impedance by partial least squares algorithm;finally,the obtained harmonic impedance is substituted into harmonic responsibility.The allocation formula calculates the harmonic responsibility of the utility company and the user at the public connection point.Finally,the simulation and engineering examples verify that the proposed method only needs to measure the harmonic voltage value of the common connection point and the harmonic current values of each branch line to accurately distribute the harmonic responsibility,in practical engineering applications.Easy to operate and more practical.