Publication

Abstract : This work aims to create a test bed for analyzing the performance characteristics of any electric vehicle motor via simulation and emulation. Given test bed can emulate the load torque which an electric motor may experience in actual drive conditions. The core part of the test bed comprises of a Permanent Magnet DC (PMDC) generator which is controlled by a special chopper circuit to emulate the mechanical characteristics of any electric vehicle. The vehicle's mechanical characteristics at various speeds is emulated by controlling the special chopper circuit connected to the DC generator which in turn controls torque the test motor will experience as both are connected via same shaft. The mass of the electric vehicle, frictional coefficients, tire radius and other functional elements are input parameters that can be entered by the user. Using these parameters, the load torque that an electric vehicle motor should experience is calculated from electrical vehicle simulation model based on the equations of various load forces acting on the vehicle for a given speed. According to the calculated torque value, chopper circuit of DC generator is controlled to emulate the torque for a given speed. The system can also be fed with a variable drive cycle. To test the effectiveness of test bed, DC motor drive is coupled to the test bed and the performance verified using MATLAB/Simulink.