Yankuang Grid Line Relay Calibration And Improvenent Of The Parameters

All large or super huge enterprises in our country are state-owned business, and they are mainstays of national economy. Their production operation and economic benefit plays a decisive role, so the safety of distribution network of these enterprises has a direct relation to their economic benefit. For the past few years, microcomputer protection develops rapidly and all kinds of protection emerge in an endless stream to meet more and more requirements, but there are more and more emergency in large industrial and mining establishments' distribution network. For one reason, it is the enlargement of the distribution network and the complex of the electric power network composition, for the other, it is the specificity of the distribution network of these enterprises, it has a difference to conventional electric power network composition, and the relay protection doesn' t solve these problems commendably.This paper points out that the low-voltage and short wirings are so many, and traditional stage type current relay protection which is widely used in low-voltage short transmission line, is setting difficulty and easy to action without sequence. It is very difficult to satisfy the demands of the modem electric power system development. This paper analyzes the characteristics of low-voltage short transmission line fault and the relative merits of relay protection used in this field on the foundation of the present research situation. This paper represents a compound ratio protection scheme used in complex current, which applied to short transmission line in middle or low-voltage power system. Through the introduce of this protection, it explains the microcomputer algorithm and all kinds of differential protection, and how to choose the short transmission line criterion of differential protection on this base.We draw the PSASP operational software which is used in high and supper high voltage distribution network into low-voltage distribution network, and improve the service conditions of PSASP operational software. We simplify and approximate the enterprise distribution network parameters, through modeling and inputting parameters, and computing the short circuit current, we get the value of short circuit current of every node and wiring.To analyze the distribution network of YANKUANG we use PSASP to model it, and compute the short circuit current, then we get the value of short circuit current. Through analyzing its relay protection deployment and accident in the past few years, we find that three service areas relay protection deployment is unreasonable. We compared the value of short circuit current and fixed value of intrinsic relay protection and analyze this three service areas relay protection deployment, We get its lacking, we change it into fiber differential protection, and it can meet the requirements of enterprise distribution network.At last, this paper outlooks the new technology and new principle relay protection application in enterprise distribution network, and it proposes the self-adapting theory and intelligent control theory digital information processing theory and so on, to solve the relay protection deployment in enterprise distribution network.