| Title |
Control Strategy of Improved Transient Response for a Doubly Fed Induction Generator in Medium Voltage Wind Power System under Grid Unbalance |
| Authors |
Dae-Su Han, Yong-Sug Suh ; |
| DOI |
10.6113/TKPE/2015.20.1.91 |
| Keywords |
Converter; DFIG; Unbalanced grid conditions; Wind power system |
| Abstract |
This paper investigates control algorithms for a doubly fed induction generator with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage wind power system under unbalanced grid conditions. Negative sequence control algorithms to compensate for unbalanced conditions have been investigated with respect to four performance factors: fault ride-through capability, instantaneous active power pulsation, harmonic distortions, and torque pulsation. The control algorithm having zero amplitude of torque ripple indicates the most cost-effective performance in terms of torque pulsation. The least active power pulsation is produced by a control algorithm that nullifies the oscillating component of the instantaneous stator active and reactive power. A combination of these two control algorithms depending on operating requirements and depth of grid unbalance presents the most optimized performance factors under generalized unbalanced operating conditions, leading to a high-performance DFIG wind turbine system with unbalanced grid adaptive features. |