A new three-phase varying-band hysteresis current controller for voltage-source inverters

Three independent hysteresis controllers are often used to control the currents of a neutral isolated well- balanced load through a three-phase voltage-fed inverter, because of their simplicity and robustness. But this control structure also has some drawbacks, such as the destruction of the inverter if its highest switching frequency is not limited and the interdependence of the load phases. This article shows how to limit this frequency in a single-phase case and how to extend this result to the three-phase case, through a transformation avoiding the complexity of most solutions proposed until now.