Stator-flux-oriented control of a doubly-fed induction machine with and without position encoder

The control of a doubly-fed induction machine (DFM) with and without the use of a rotor position encoder is examined. First, a stator flux linkage oriented control scheme for power and speed control with a position encoder, shows the high performance control capabilities of this control arrangement and serves as foundation for the sensorless scheme. The power-control method is then applied to a sensorless method, based on a previous control arrangement. This method is then extended to derive a sensorless speed-control mechanism for the DFM. All control schemes are implemented and performed on an experimental test system, comprising two 80C167 microcontrollers and a 2.25 kW wound rotor induction machine