An induction machine servo with one current controller and an improved flux observer

A stator flux oriented torque control system for induction machines with a new flux control and flux estimation method is presented. The stator flux linkage is controlled directly, i.e. without any intermediate current control and the torque is controlled with current control of the torque producing stator current component. A stator flux observer is presented that is partly implemented in analogue integrators with a digital signal processor in a feedback loop. The entire concept is a high performance induction machine servo with a minimum of controllers and a minimum of hardware