Identification Parameters Of Equivalent Using PMU For Developing Adaptive Pacs For Distribution Networks With Electricity Sources

Abstract

Today, there is a tendency to introduce distributed generation, including an increase in the share of renewable energy sources. A significant amount of distributed generation leads to the inefficiency of the traditional approach to calculating the parameters of relay protection operation (offline), and as a result, can lead to improper relay protection and reduce the reliability of power supply.A significant drawback of the existing approach to the calculation of the trigger parameters is the representation of the power system in two modes: maximum and minimum modes.In the conditions of rapidly changing modes of generating electricity and generating loads, which depend, among other things, on weather conditions, in distribution networks with a high proportion of distributed generation, it is necessary to calculate and adjust the relay protection and automation parameters according to the current mode.To solve the problems of adaptability trigger parameters of relay protection in accordance with the current mode, it is proposed to create and maintain up to date a mathematical model of the electrical network, the electrical equipment of which is protected (hereinafter referred to as the internal network). To create an accurate current mathematical model of the electrical network, it is proposed to use the current equivalent of the external power system. Since the configuration and parameters of the external power system may not be known, it is proposed to synthesize its topology. It is assumed that the number of communication points (boundary points), as well as communication elements between these points (transformers, autotransformers and power lines), the parameters of which are known to us. The article proposes to represent the equivalent of an external energy system in the form of a polygon whose vertices are interconnected and communication lines with the internal system depart from the vertices. To identify the parameters in the work, it is proposed to use analytical and optimization methods.As input information, currents and voltages taken by PMU devices are used. It is proposed to use the Matlab software package, in particular, Simulink, as a modeling environment for an equivalent model. Certain parameters of the external equivalent must correspond to the real mode of the distribution network at the considered communication points in emergency and normal modes.