Optimal system efficiency operation of dual PMSM motor drive for fuel cell vehicles propulsion

Electric Vehicles (EVs) develop rapidly with the concerns of gas emission and energy crisis. Electric Motors, those are used for EV propulsion must have high efficiency for maximum utilization of the energy from batteries and/or fuel cells. This paper aims to address how to achieve the optimal system efficiency of multi-motor drive system, which has not been addressed previously. Based on the measurement or estimation of the real-time load condition and the efficiency optimization strategy, Digital signal processor (DSP) coordinates the work between the two motors and sets reasonable working mode of the inverter, and then improves the overall efficiency of the propulsion system notably. Fault-tolerant strategy base on the master-slave motor concept is also discussed to ensure the reliability of the system both under health and various faulty conditions. The paper presents the details of the experimental setup and measurement for the improvement of the system efficiency. Data obtained from this study will provide the preliminary understanding on how to achieve the optimal efficiency of multi-motor drive system.