Predictive digital hysteresis current control

A symmetrical band hysteresis current control technique of voltage source inverters is proposed, which uses digital calculation to predict the proper hysteresis band in order to commutate at fixed frequency. The technique is self-adapting to load and supply parameters, and does not require any A/D conversion but only timing measurement; also it can be synchronised with an internal or external clock The implementation is done by means of a standard micro controllers and very few external components. Simulations and experimental tests confirmed the excellent performance of the indicated method.