Diode Clamped Multi-Level Inverter Controller Connected To A DFIG Wind Turbine Configured DVR to Get Smoother Output Voltages

Abstract

The proposed technique in this paper is to remunerate system imbalance voltage utilizing the doubly fed induction generator (DFIG). In this, a diode clamped multi-level inverter or neutral clamped inverter in addition to dynamic voltage restorer employed to compensate the voltage unbalance. To remunerate the unbalanced voltage at the coupling point (PCC), the symmetrical per phase technique is used to calculate the current components of negative sequence required to remunerate the unbalanced voltages at coupling point. By using this technique, the torque oscillations in the machine are avoided by applying voltage at the stator of the machine. By using multi-level inverter (MLI), the smoother output voltages are obtained for the small amount of sequence currents. The two converters, one is at grid side (GSC) and other is at rotor of the machine (RSC) are the components used to inject the sequence components into the machine. This technique is validated by the simulation results which improves the smoother output voltages at PCC by reducing the oscillations in the electromagnetic torque.