Bit-Stream control of Doubly-Fed Induction Generators

Bit-Stream based control, which uses one bit wide signals to control power electronics applications, is a new approach for controller design. A Bit-Stream based control system for the Rotor Side Converter (RSC) of a Doubly Fed Induction Generator (DFIG) is proposed to demonstrate that the Bit-Stream control technique is suitable for complex vector control tasks. A new stator flux estimator and reference frame calculation unit are developed and used to control the rotor current of the generator. A 3.7 kW, 400 V generator and Bit-Stream control system are simulated using Mentor Graphics´ ModelSim. Simulation results show that the rotor current control system offers decoupled control of the torque and flux producing components of the rotor current vector, and the ability to operate in supersynchronous or subsynchronous modes.