Analyse eines neuen Stromrichter- und Flussregelkonzepts zur Realisierung hochdynamischer Asynchronmaschinenantriebe mit extrem weitem Feldschwächbereich

The paper presents an inverter concept for the realization of an induction machine drive with an extremely wide constant power range. The stator winding of the induction machine is split up into two isolated and quasi-bifilar wound three-phase winding systems. The series operation of the two winding sets provides very high torque at low stator frequencies while keeping the machine terminal and the inverter DC link current relatively low. However, due to the high number of turns field weakening is necessary at low frequencies (approximately at 50% of rated speed) already. Nevertheless, with the help of an electronic transition from series to parallel stator winding arrangement the machine flux can be restored to its nominal value as given for rated machine speed. Consequently, the break-down torque is increased by a factor of 4 which gives the basis for a high maximum speed with constant machine power.