基于VSC的高压直流输电系统的非线性控制

基于电压源型换流器的高压直流输电系统是一个多变量、非线性、强耦合的系统,建立精确的换流器数学模型比较困难。文章采用非线性变换和非线性系统反馈线性化理论,建立了同步旋转坐标系下VSC—HVDC系统换流器的非线性数学模型,结合线性系统最优控制原理,设计了VSC—HVDC系统的状态反馈线性化解耦控制器,实现系统有功功率和无功功率的解耦控制。基于PSCAD/EMTDC的数字仿真,验证了所设计的控制器具有良好的控制性能。

Nonlinear Control of VSC-Based HVDC Transmission System

Because the VSC-based HVDC transmission system is a multi-variable,nonlinear,and strongly coupled system,it is hard to establish an accurate converter mathematic model.By using nonlinear transformation and nonlinear system feedback linearization theory,nonlinear mathematic model of VSC-HVDC system converter in synchronous rotating coordinate system is established.And by combining theory of optimal control for linear systems,linearised state-feedback decoupling controller for VSC-HVDC system is implemented to realize decoupling control of system active and reactive power.PSCAD/EMTDC-based numerical simulation validates that the designed controller has good performances.