Reduction of electromagnetic torque oscillations of DFIG based on DPC in unbalanced grid voltage condition

فاقد چكيده فارسي

Abstract—In this paper, a new control algorithm based on direct power control (DPC) is proposed for a doubly fed induction generator (DFIG) under unbalanced grid voltage conditions with the aim of reducing generator torque oscillations. For this purpose, the generator model and the grid and rotor side converters are expressed in positive sequence synchronous reference frame and the generator performance and oscillating power components are shown in unbalanced grid voltage conditions. The separation of the oscillatory components is simply based on the definition of these components in the positive sequence of the electrical parameters of the system. Then, using feedback of these oscillating components at the converter reference power, a significant reduction in the electromagnetic torque oscillations of the generator is achieved, as well as a decrease in DC voltage oscillations between the grid side and rotor side converters. The simulation results show that the proposed method can reduce torque and voltage fluctuations of the DC-link simultaneously in addition to separately controlling the active and reactive powers.