A novel speed sensor-less stator flux-oriented vector control of dual-stator induction generator for grid-tied wind energy conversion system

The paper proposes a novel speed sensor-less stator flux-oriented vector control of dual-stator induction generator suitable for high-power applications in grid-tied wind energy conversion system. In this control strategy, the magnitude and angle of the flux are directly estimated by the measured stator voltages and currents. As the voltage and current sensors are placed on the stationery stator part, therefore, the proposed control strategy does not affect the robustness of the machine compared to the conventional rotor flux-oriented vector control where the sensors need to be mounted on the rotating part of the machine. Moreover, the proposed speed encoder-less stator flux-oriented vector control eliminates the use of speed encoder, thereby reducing the cost and eliminating the error caused due to faulty speed measurement by the speed encoder of the overall system. The performance of the novel speed sensor-less stator flux-oriented vector control scheme has been verified by simulation and then experimentally on a 2 hp, 415 V, 50 Hz, three-phase dual-stator induction generator drive. The control strategy was implemented through dSPACE 1104 DAC card. From the simulated and the experimental results, it is evident that the proposed control strategy reflects improved performance w.r.t. conventional rotor flux-oriented vector control. In this manuscript, a novel speed sensor-less stator flux-oriented vector control of DSIG machine has been proposed which has been incorporated in a grid-tied, variable speed wind energy conversion system. This control scheme not only proves to be more efficient in terms of speed estimation but also increases robustness of the overall system. Moreover, omission of speed sensor not only increases the robustness of the system but also reduces the chance of error caused owing to mis-measurement of speed by the speed encoder. The speed of the generator shaft is estimated from the motor terminal variables, that is, stator voltage and currents, so the system complexity gets increased to an acceptable extent. The overall control scheme is being simulated in MATLAB environment, and the results obtained in simulation are validated through appropriate experimental setup. Moreover, instead of using any DC motor as prime mover, an artificial wind generation unit is being constructed to form the experimental test bench. image