海上风电场黑启动系统的风柴协同控制策略

在风电平价上网政策的推动下中国海上风电场建设加速,未来大规模的海上风电场将会成为沿海地区局域电网的重要供电电源。当沿海局域电网发生大停电时,海上风电场若具备作为黑启动电源的能力将显著加快电网恢复过程。为启动沿岸无黑启动能力的火电机组,文中提出了利用海上风电场配置的小容量辅助柴油发电机作为支撑电源启动海上风电机组,后经主变压器和高压海底电缆向陆上火电机组供电的黑启动方案。为改善黑启动系统的频率调节能力以及在投入高压海底电缆时维持系统电压稳定,分别提出一种风柴协同调频控制和一种考虑柴油发电机功率极限的动态无功补偿控制,后者利用了风机网侧变流器(WGSC)作为静止无功发生器(SVG)运行。最后在PSCAD/EMTDC上依据实例搭建了海上风电场黑启动模型,验证了所提方案及策略的可行性和有效性。

Coordinated Control Strategy of Wind Turbine and Diesel Generator for Black-start System of Offshore Wind Farm

The construction of offshore wind farms in China has been accelerated with the promotion of wind power parity policy. In the future, large-scale offshore wind farms will become an important power supply for local power grids in coastal areas. When power outages occur in coastal local power grids, if offshore wind farms can act as black-start power sources, the restoration process of power grids will be significantly accelerated. In order to start coastal thermal power generation units without the black-start capability, a black-start scheme is proposed, which uses small-capacity auxiliary diesel generators equipped in offshore wind farms as supporting power to start offshore wind turbines, and then supplies power to onshore thermal power plants via main transformers and high-voltage submarine cables. In order to improve the frequency regulation ability of the black-start system and maintain the system voltage stability when the high-voltage submarine cable is put into operation, a coordinated frequency modulation control method of wind turbine and diesel generator and a dynamic reactive power compensation control method considering the power limit of diesel generator are proposed, respectively. The latter uses wind turbine grid-side converters as the sources of static reactive power. Finally, a black-start model of offshore wind farm is built on PSCAD/EMTDC to verify the feasibility and effectiveness of the proposed operation scheme and control strategy.