Elimination of Deadtime Effect on Resolver Offset Estimation Using the Pulsating Current Command for Electric Vehicle Application

An accurate position measurement of the rotor is critical for the success of field-oriented control (FOC) for interior permanent magnet synchronous machines (IPMSM). This paper proposes a back electromotive force (BEMF) based approach to determine the resolver offset (RO), commanding a pulsating current to eliminate the effect of inverter dead-time. The results show that the proposed approach successfully eliminates the effects of dead time on the estimation of RO, and estimation accuracy is higher than the method employing zero current command. The simulation results are experimentally verified by dynamometer testing.