Measurement-Based Modeling And Model Application Of Traction Power Supply System

As the characteristics of fluctuation, nonlinearity and asymmetry, electrified railway traction loads have arose some hazardous effects to security and stability, reactive power compensation and voltage control, power supply quality of power system. The research on the influence of traction loads to power system has realistic engineering meaning for ensuring security and stability of power system.Power system simulation is believed as an indispensable tool for power system planning, design, operation, research etc. So research on the influence of traction loads to power system have two factors: one is how to construct the load model accurately reflecting the synthesis load characteristics of traction loads .and the other is how to imply the load model of traction loads to power system simulation. This paper studied the two aspects of research on the influence of traction loads to power system.Based on the actual load structure of the traction power supply system, a new load model is instructed,which includes induction motor, traction motor, constant impendence and reactive power compensator.To settle the time-variation problem of traction load in measurement-based load modeling, this paper uses the method of classification and synthesis for dynamic load characteristics by modern statistical analysis priniple. By the parameters identification, this paper provides recommended parameters of several different traction conditions. It can provide useful reference for the traction load model applying to power system simulation. The results of a instance verify the improved description of measured data and the effectiveness and rationality of the method of the classification and synthesis.The load model of traction loads is presented by PSASP/UDM (Power System Analysis Software Package/User Defined Model), which is based upon the mathematical description of the traction power supply system. All of load components are completed by basic function dialogs. At last, the correctness of user defined model of traction loads is verified with the example-WSCC 9 power system (Western Systems Coordinating Council 9). A simple analysis on the synthesis load characteristics of traction loads is accomplished in Hunan power grid.This paper constructs the load model of traction loads with PSASP/UPI (Power System Analysis Software Package/User Program). The user program (UP) of traction loads, which is composed by C++ language, then can be carried out with transient stability analysis module together by turns on PSASP/UPI through the interface transmitted data. It offers a new way of available practical model applying to power system simulation and research on the influence of traction loads to power system. At last, using the example EPRI-36 power system (Electric Power Research Institute 36) verifies the correctness of user interface of traction loads.