A simple and self-adapting high-performance current control scheme for three phase voltage source inverters

An adaptive optimized regulator (AOR) for three-phase voltage source inverters is presented. The zero-voltage vectors are used systematically to reduce the switching frequency and can be reached by switching only one inverter leg. In the steady stage the controller applies to the machine only those three voltage vectors which are directly adjacent to the machine voltage (similar to pulse width modulation). Adaptive identification of position and amplitude of the determining machine voltage vector is realized by multilevel hysteresis comparators and a switching table. The dynamic performance is as excellent as for the three-phase bang-bang controller, and the hardware implementation is very simple