基于EMTDC的HVDC极控制的建模与仿真

为了配合高压直流输电系统在我国的发展,介绍了高压直流输电极控制系统的基本结构和工作原理,运用PSCAD/EMTDC仿真软件对极控系统中的最主要功能,如定电流控制、定电压控制、定熄弧角控制以及限幅环节进行了数字建模,并应用于Cigre的HVDC标准测试系统,对4种工况进行仿真计算,仿真结果表明该极控系统具有良好的跟踪设定参考值变化的能力;当交、直流系统发生故障时,控制系统调节快速,能迅速抑制故障,并使故障恢复后直流输电系统能平稳过渡到稳定工况,说明所建仿真模型的正确性。

Modeling and Simulation of HVDC Control System Based on EMTDC

In recent years,HVDC transmission project is developing greatly in the homeland.Be different from ac system,the natural operation and protection of HVDC transmssion system rely on its control system.The control system of HVDC decides the natural operation point and adjusts the rectifier and inverter process,it is very important for HVDC technique utilizatiion.The pole control and the converter control system of DC converter station are the key techniques in HVDC project.The basic structure and principle of HVDC transmission project pole control system are introduced in this paper.Modeling of basic function such as constant current control,constant voltage control,constant extinction angle control and limit function are realized based on PCAD/EMTDC.The model is applied to HVDC criterion testing system I-Cigre Benchmark I main circuit.Simulation and calculation in four modes,such as steady state,reduce DC voltage mode,a short circuit fault at the DC line and 3-phase short circuit fault at the rectifier ac side,corresponding DC voltage curve,DC current curve,DC power curve,and angle curve are given to prove that the pole control system has an ability to track the change of the reference value.When ac force HVDC transmission system come back to steady state.These proved the correctness of the simulation model in this paper.