Electric and hybrid vehicle power electronics efficiency, testing and reliability

System efficiency together with the reliability are the most critical factors in the design, characterization and operation of Electric and Hybrid Vehicles. This paper summarizes those aspects from the system level down to the component details and shows practical methods for evaluation and improvement. This paper concentrates on a small to medium size personal vehicles in electric vehicle (EV) and parallel hybrid (HEV) configuration. Even though the main focus of the paper is the traction inverter, other critical high power EV and HEV building blocks such as a DC/DC and AC/DC on board charger are also characterized and discussed to certain depth. Some test methods for evaluation of the individual units and their components including extreme conditions such as heavy overload, short circuit and overvoltage are explored along with examples of experimental results on the prototype units.