The brushless doubly-fed machine (BDFM) is based on the technic of field oriented control and the performance of its adjustable-speed drive can ultimately meet the need of the operation.

Based on the theory of vector control and automatic control system, the vector control system of current model for doubly-fed asynchronous machine with field-oriented rotor was established.

The controller provides an adaptive estimate of the turbine shaft torque as a torque reference for a field oriented squirrel cage induction machine.