Substation DC Power System Design And Abnormality Analysis

As the working power of protection, monitoring and control, automatic devices, DC system is the infrastructure of the power system control and protection in transformer substation. In the case of the substation used AC disappeared, the DC system must ensure continuous supply of power. it can be said the reliable operation of the DC system is to ensure the safe operation of the power system, so more and more people payed more attention on the research on the DC system in recent years. With modern science and technology, especially the development of computer technology and communication technology, power systems developed toward integrated automation, network centralized direction. It put higher requirements forward the stability and reliability of substation DC system. Therefore, it’s important to research the design of substation DC system, analyze the fault that may be encountered in the DC system and propose solutions to the different types of DC system fault.This paper described the structure of the DC system, analyzed the function and the principles of the various components of DC system, analyzed the design principles and the issues that need attention of the battery, charging device, the voltage of the DC bus, the wiring of DC system, the feed network of DC system and the DC switchgear. This paper analyzes the problem of DC system abnormalities that may occur from the component failure of DC system, the two circuit faults in DC system and the DC system ground fault, and put forward the corresponding solutions to solve these problems. Analyzed the DC system ground fault, discussed the treatment of different types of DC ground fault with case. Studied the technology of DC system fault detection. Analyzed the principle of the method of the balanced bridge, the AC signal injection and DC detection. Analyzed of the advantages and disadvantages of each method. Described the operating characteristics of the breaker in DC system. Proposed a method and principles of staged difference coordination in DC system.