基于特高压交直流混联电网的调相机无功补偿及快速响应机制研究

为了改善特高压交直流混联电网的无功功率调节能力,国网公司近年来在送、受端加装了很多了大型调相机。目前,大型调相机的暂态及动态特性复杂,主要受电机本体及励磁系统的影响,也与特高压交直流电网结构及故障等因素有关。为充分发挥和提升大型调相机对特高压电网电压的支撑作用,满足特高压交直流混联电网对大型调相机无功快速出力的需求,根据特高压直流的云-广±800kV电网结构搭建PSCAD/EMTDC仿真模型。结合目前实际的湖北电网运行特点,研究大型调相机对受端电网交、直流侧电网电压的影响。分析大型调相机对系统电压的无功支撑作用以及快速响应机制,为今后国家电网公司在特高压直流电网中安装大容量的调相机提供参考和建议。

Research on reactive power compensation and fast response mechanism of synchronous condenser based on UHVAC/DC hybrid grid

In order to improve the reactive power regulation capability of UHV AC-DC hybrid power grids, State Grid Corporation of China has recently installed a large number of large-scale synchronous condensers in the sending and receiving ends. At present, the transient and dynamic characteristics of large-scale synchronous condensers are complex, which are mainly affected by the motor body and excitation system and also related to the structure and fault of UHV AC-DC power grid. In order to fully utilize and enhance the supporting role of large-scale synchronous condensers to UHV grid voltage, and meet the demand of UHV AC-DC hybrid power grid for synchronous condensers fast reactive power output, this paper builds a PSCAD/EMTDC simulation model according to the UHV DC Yunnan-Guangdong ±800 kV grid structure. Combined with the actual operating characteristics of Hubei Power Grid, the influence of large-scale condensers on the voltage of the AC and DC side grids at the receiving side is studied. Besides, the reactive power support function of the synchronous condensers to the system voltage and its fast response mechanism are studied, which will give the reference and recommendations for State Grid Corporation of China in the installation of synchronous condensers in future UHVDC grid. This work is supported by National Natural Science Foundation of China (No. U1766207).