Research On The Division Technology Of Harmonic Responsibility In Distribution Network

The result of the harmonic source is often the result of the system side and the user side.The identification of the harmonic source is helpful to coordinate the contradiction between the power supply and the user.If the respective responsibilities for power quality problems are distinguished,the contradiction between power supply companies and users caused by power quality problems can be easily resolved,and it will help improve the power quality of users and the service level of power supply companies.This article first introduces the index of harmonic responsibility division,theoretically analyzes the harmonic source identification technology based on power flow,and combines the simulation analysis to compare the advantages and disadvantages of different identification methods and the applicable scope of work.Then,from the qualitative and quantitative perspectives,the advantages and disadvantages and the applicable scope of work of the single harmonic source responsibility division technology based on different algorithms are compared.In the actual power system,each parameter and system operation conditions are time-varying,and the multi-harmonic sources at the public bus are widely distributed and cannot be specifically located.Therefore,this paper proposes an improved partial least squares method for dividing the responsibility of multiple harmonic sources.This method regards other harmonic source users and the system side except those concerned with harmonic sources as the equivalent system side,and converts the division of multiple harmonic source responsibilities into several single harmonic source responsibilities.In order to ensure a good correlation between the real part and the imaginary part of the harmonic impedance estimation results,this paper builds a data screening index factor based on the idea of hybrid modeling.First,the sampling point data with good linearity is filtered out,and then the complex number domain partial least squares method is used to estimate Pay attention to the equivalent system-side harmonic impedance corresponding to the harmonic source,and finally realize the division of responsibility for multiple harmonic sources.Through various simulations and case analysis,it can be seen that the improved method of division of responsibilities for multiple harmonic sources proposed in this paper is very accurate for the division of responsibilities of multiple harmonic sources in the actual power system.Finally,from the engineering point of view,based on the data in the PQDIF format,according to the short-circuit capacity at the PCC and the measurable voltage and current parameters,a method to approximate the division of responsibility for multiple harmonic sources in engineering is given.