External equivalence method of power system based on psd-bpa auxiliary switch

Abstract

The invention provides a PSD-BPA auxiliary switch-based electric power system external equivalent method. The method comprises the following steps of: firstly, adding auxiliary switches at an externalsystem side of a connecting line, wherein one ends of the auxiliary switches are external system nodes and the other ends of the auxiliary switches are newly added auxiliary nodes; secondly, carryingout network equivalent on electric power system models which are added into the auxiliary switches by using an SCCP program, selecting the external system nodes and the auxiliary nodes as equivalentnodes, and enabling to-ground admittance at the external system side of the connecting line to be equivalent into to-ground equivalent parameters of the auxiliary nodes, but not into external system equivalent nodes; and finally, in the equivalent result, removing the auxiliary nodes and all the equivalent impedances connected with the auxiliary nodes, and only remaining the external system equivalent nodes and equivalent impedances between the equivalent nodes to form external equivalent models of research systems. By adoption of the equivalent method, research systems can be completely separated from external systems, so that the system external equivalent is correct and reliable.

Description

technical field [0001] The invention relates to a power system equivalent method, in particular to a method for performing static equivalent value of a power system by using PSD power system analysis software. Background technique [0002] With the development of the electric power industry, the national power grid has gradually formed a huge interconnected system, which has improved the quality of electric energy and the reliability of power supply. However, such a huge interconnected system makes the computer simulation of the power system very complicated, especially when the electromagnetic transient simulation of the power system is performed, the memory and calculation speed of the computer often cannot meet the fast requirements, so the equivalent method has to be resorted to , to replace the uninteresting part of the system (external system), and only keep the part that needs to be studied (research system), so that the simulation calculation scale can be greatly red...

AI Technical Summary

Problems solved by technology

When SCCP is used for system equivalence, the line-to-ground admittance will be equivalent to the ground-to-ground parameters of the nodes on both sides, or the ground-to-ground parameters of the equivalent nodes include half of the ground-to-ground parameters of the lines connected to it This causes half of the ground-to-ground admittance of the line connected to the external system in the research system (hereinafter referred to as "connection line") to be equivalent to the external system, resulting in the inability to completely separate the research system from the external system

Therefore, for the power system model without circuit breaker structure between tie lines and external system nodes, SCCP cannot achieve the real system external equivalent

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