渝鄂背靠背投运后水布垭近区电网调压策略优化研究

Voltage Regulation Strategy Optimization of Power Grid near Shuibuya Power Station with the Hubei-Chongqing Back-to-Back VSC-Based HVDC Project in Operation

渝鄂背靠背柔性直流工程投运后水布垭电站近区电网变为湖北交流电网末端,其电压无功特性显著改变。通过对工程投运前后水布垭电站近区电网的无功补偿设备配置情况进行梳理,分析了工程投运后近区电网渔峡电压偏高和恩施电压偏低问题形成原因。采用电力系统分析综合程序(PSASP)对电站近区电网的无功电压特性进行仿真计算,仿真结果表明施州柔直、恩施变和水布垭对降低渔峡电压效果基本相同,施州柔直对提升恩施电压的效果优于水布垭。最后,提出了综合考虑电网无功补偿设备资源配置、柔直电压控制死区和水布垭机组工况的调压优化策略。该控制策略能够保持渝鄂背靠背柔性直流工程投运后水布垭电站近区电网电压稳定,有利于系统的安全稳定运行。

The power grid near Shuibuya Hydropower Station becomes the end of Hubei AC power grid with the Hubei-Chongqing back-to-back VSC-based HVDC project put into operation,and the reactive power voltage characteristics of Shuibuya power station change significantly.By sorting out the configuration of reactive power compensation equipment for the regional power grid near Shuibuya power station both before and after the project is put into operation,this paper analyzes the causes of slightly higher voltage in Yuxia and slightly lower voltage in Enshi on the neighboring power grid after the project is in operation.And then,the paper uses the power system analysis and synthesis program(PSASP)to simulate the reactive voltage characteristics of the power grid near the station.The results indicates that Shizhou VSC-based HVDC,Enshi transformer substation and Shuibuya station have basically the same effect on reducing the voltage of Yuxia,while Shizhou VSC-based HVDC increases the voltage of Enshi more effectively than Shuibuya station.Finally,the paper proposes a voltage regulation optimization strategy comprehensively considering the allocation of reactive power compensation equipment,voltage control deadband of VSC-based HVDC and Shuibuya unit working condition.The control strategy can keep the voltage stability of the regional power grid near Shuibuya station after the back-to-back VSC-based HVDC project of Hubei-Chongqing is put into operation,which is beneficial to the safe and stable operation of the system.