Research on the Renewable Power Phase-Locked Stability Considering the Influence of Reactive Power Compensation Device

As the large-scale integration of the off-shore wind generation, the grid strength of the wind-thermal-bundled transmission system has become much more weaker and phase-locked instability problems are becoming more easily to encounter. As the phase-locked stability is mainly affected by the terminal voltage dynamic of the renewable generation, the reactive power compensation device which influence the terminal voltage dynamic will play a great role in phase-locked stability. However, the phase-locked stability interactions between the reactive power compensator and renewable generation are still not well researched. In this paper, PLL phase angle motion characteristic considering the influence of reactive power compensation device has been proposed and the influence of reactive power compensation device has been analyzied. Then, the calculation method of reactive power compensation device capacity is proposed, which can accurately calculate the capacity of reactive power compensation device under the constraint of phase-locked stability. At last, case studies have been carried out to verify the correctness and effectiveness.