含统一潮流控制器的风火打捆并网稳定性分析

Stability Analysis of Wind-Thermal Bundled Power System Integration Based on UPFC

为了增加风电并网的稳定性,提出了风火打捆直流外送的方案。当风电功率波动剧烈时,可以利用火电出力减弱风电功率波动带来的不利影响,保证电力输入至受端电网时的电压稳定。然而当受端电力系统出现故障时,需要无功装置维持受端电网稳定性。UPFC作为功能全面的无功补偿器件之一,既可以控制潮流,还可以在故障时候提供无功补偿,提高系统稳定性。在DIg SILENT软件中搭建了在受端配置UPFC的风火打捆电网模型,研究了不同工况下系统送、受两端的电压与功率特性。仿真结果证明了所建立系统的可行性及控制方案的有效性。

To effectively improve grid-connected operation stability of wind farm, the structure of wind-thermal bundled power transmitted by DC system is proposed. In the case of wind power fluctuations, thermal power output can be used to mitigate the influence of wind power to ensure voltage stability at the receiving end. When fault occurs at the receiving-end grid, reactive compensation equipment must be added to maintain the stability of the grid. Unified power flow controller（UPFC）, as a multi-purpose reactive power compensation equipment, can not only control power flow but also provide reactive power compensation and improve the system stability. The model of UPFC with wind-thermal bundled system is established in DIg SILENT software, and voltage and power characteristics of sending and receiving ends under different operating conditions are investigated. The simulation results demonstrate the feasibility of the proposed system and the effectiveness of the control strategies.