Development of a Testbed for Evaluation of Electric Vehicle Drive Performance

Abstract

This thesis develops and implements a testbed for the evaluation of inverter fed motor drives used in electric vehicles. The testbed consists of a computer-controlled dynamometer connected to power analysis and data collection tools. The programming and operation and of the testbed is covered. Then it is used to evaluate three pairs of identical rating inverters. The goal is to analyze the effect of topology and software improvements on motor drive efficiency. The first test analyzes the effect of a soft-switching circuit on inverter and motor efficiency. The second test analyzes the difference between space vector modulation (SVM) and current-band hysteresis. The final test evaluates the effect of both soft-switching and SVM on drive performance. The tests begin with a steady state analysis of efficiency over a wide range of torque and speed. Then drive cycles tests are used to simulate both city and highway driving. Together, these dynamic and steady state test results provide a realistic assessment of electric vehicle drive performance.