Low Frequency Simulation of Traction System for EMC Analysis

Sammanfattning: Bombardier Transportation in Västerås is developing traction system for trains. These systems must comply with Electromagnetic Compatibility (EMC) standards. Harmonics generated by the traction system is an EMC concern. Better models of the components enables more efficient and accurate prediction of harmonics generated in the traction system. The aim of the thesis has been to improve the existing model of the traction system, with focus on the Line Converter Module (LCM). The LCM is one of the sources of harmonics in the system. The existing model does not have a line converter controller implemented. Therefore, the main part of the thesis work has been to integrate a controller into the model. The controller has been implemented in the program Simulink, while the rest of the traction system is developed in the Simulink Toolbox Piecewise Linear Electrical Circuit Simulation (PLECS). The focus of the work has been to study how the controller affects the harmonics in the system. In the thesis work harmonics up to 1000 Hz have been analysed. The results from the simulations show that the controller introduces harmonics into the system, in particular the third order harmonic prevails. In order to verify and validate the performance of the developed model, the simulation results have been compared with measurements from a Real-Time Simulation environment (RTS). The RTS utilizes the hardware of the control systems but simulates the rest of the traction system. The simulation results from the developed model show quite good agreement with the RTS measurements. However, it is important to later verify the model with real measurements from a vehicle, when such measurements become available. A main conclusion of the work is that the controller affects harmonics under 1000 Hz in the system and should be included in the model of the traction system in order to accurately predict the EMC disturbances.