基于RTDS闭环仿真的无功补偿低压投切策略测试分析

Test and analysis of reactive power compensation low-voltage switching strategy based on RTDS closed-loop simulation

为了提高电网受端动态无功补偿后电压运行的稳定性,建立了基于RTDS闭环仿真的无功补偿低压投切策略分析模型,并利用实时数字仿真(RTDS)平台建立220 kV及更高电压的控制系统。分析10 kV侧母线的有效电压发现,经过0.12 s低压动作后受到电压波动影响发生电压回升的现象,之后发生电压波动并引起正序电压的下降,不过依然没有达到du/dt超过故障判断滑差定值的临界值,实际测试期间装置并未发生动作。10 kV侧母线电压有效值分析出现了电压回升的情况,说明存在电容器投入的情况。单次投入电容器引起的电压升高为0.1 kV,经过电容器投入后可以使电压升高3.92%。

In order to make full use of the system′s reserve reactive power resources to improve the dynamic reactive power compensation ability of the receiving end of the power grid and better improve the voltage stability,the paper proposes the control strategy of on-off capacitor based on the automatic device of fast-on-off capacitor.The switching control strategy is set with system fault identification logic,low voltage input capacitor logic and overvoltage cutting capacitor logic.The simulation platform adopts digital real-time simulation(RTDS)to build the real-time simulation model of 220 kV system and above,and connects the actual dc control protection device and the automatic device of quick switching capacitor respectively,forming a double-closed-loop real-time simulation system.By setting up a variety of test projects,the paper carried out the experimental research on the basic switching strategy of the automatic device under different failure conditions,verified the correctness and effectiveness of the switching strategy,and provided important technical guidance for the engineering implementation and application of the device.