Study On Relaving Protection Of Rail Transit DC Traction System And Development Of Simulation Software

Rail transit plays a pivotal role in today’s society. For big cities, with increasing population pressure and traffic pressure, underground metro, light rail and other transportation means are gradually taken into our attention. In recent years, the development of rail transport is rapid in our country. The safety of the operation of rail transit is more and more important than before. So, the reliability of the relay of rail transit power system should take our enough attention. Rail transit power system is a AC-DC cofounding system. The relay of AC power system is similar to traditional power grid. It’s setting means are very mature. But, the study of relay of DC traction power system is still inadequate. Many large metro network relay for DC feeder breaker still rely on the experience of experts. The setting result calculated by this way is impossible applied to all the rail transit line. And the inaccuracy is also cause disoperation. So, the study of relay of rail transit DC traction power system is very necessary. Firstly, typical DC traction power supply system is introduced in this paper. The analysis of two-side supply power system widely used in our country is also included. On this basis, combining knowledge of relay, system failure is analyzed to a certain extent. The fault system is divided into transient and steady-state short-circuit, to lay the foundation for the later to the value of relay setting.After, DC traction systems commonly used to protect analyzed. According to the unique characteristics of rail transit system improvements, put forward a series of new tuning program:If the current protection action value in the case of short-circuit the midpoint of tuning to ensure the protection of no dead; DDL protect samples smoothed to reduce start frequent starts and other elements. In addition, how to improve cooperation between protected protection reliability and selectivity is also a focus of this article. The last chapter will conduct simulation.Finally, this article will discuss how to develop a suitable rail transit DC traction system protection of professional software, this software help guide the setting more scientific staff to develop or adjust the entire order, the scarcity of similar software also makes this work very necessary.