Real-time optimization of dead time for motor control inverters

A correlation-based control technique was used previously to optimize dead time in synchronous rectifier-based buck converters. Here, the correlation method is applied to the problem of optimizing dead time in motor drive inverters. The approach works on each inverter leg. It optimizes dead time to minimize input current either to each leg or to the inverter bridge as a whole. This in turn minimizes switching loss as current commutates between inverter devices. The approach is shown to be stable whenever switching action takes place. An experimental implementation is given. Results show a significant reduction in switching loss for the test inverter.