Analysis on Energy Flow of Electric Vehicle

In order to appraise energy consumption and utilization of an electric vehicle, energy flow test method was proposed. The tests were completed in a 4WD chassis dynamometer test cell with a thermal chamber. During the test, high-voltage battery, motor system, DCDC, climate control system, low-voltage accessories were monitored. Then, energy consumption characteristics of each system or component were analyzed, and energy flow was calculated. Based on energy flow graph, evaluation indexes from vehicle level to system or component level that represent energy consumption and utilization were proposed. By changing the test conditions, the impacts of temperature and drive cycles were quantified, and the accuracy of energy flow was further improving. Finally, according to energy flow results at different test conditions, optimized schemes were proposed.