Research And Application Of Power Quality Test And Evaluation Technology For Power Supply In City Track Traffic System

Urban rail transit includes three types of transportation:metro,elevated road and light rail.The metro travels under the ground and doesn’t occupy the ground space.What’s more,compared to other types of communications,the metro has great superiority owes to its special tracks.For instance,The metro has advantages in many aspects,such as fast running,less chances for traffic jams,safe,comfortable and less interference.The metro brings us many benefits, at the same time causes negative effects, for instance, the metro pollutes the power quality. This article will discuss the power quality problem brought by metro and the solution, and finally, a better method of improve and harness power quality is mentioned after analyzing the examples in a certain city railway system.This mainly discussed the following contents:(1) This paper analyzes the reason for the harmonic in24pulse rectifier unit from two aspects——the theory and the silulation.The result is proved to be correct by calculating the effective data.(2) This artice reveals the characters of the power quality in the urban rail transit load by calculating the effective data from two aspects——the harmonic character and the power character.(3) This paper uses a new method to measure and calculate the voltage fluctuation,which improves the maneuverability and the precision.(4) A method of solving the harmonic and reactive power problems is goven.The method is proved to be feasible by simulating.