电压源换流器高压直流输电系统的精确线性化变结构控制器设计

Design of Exact Linearized Variable-Structure Controller for VSC-HVDC Power Transmission System

建立电压源换流器高压直流输电系统在同步旋转dq坐标系下的暂态非线性数学模型。为实现对这个非线性系统的控制器的直接设计,采用状态反馈精确线性化的方法,将非线性的数学模型转化成线性的形式。然后,运用变结构的控制方法,设计整流侧和逆变侧的控制器,从而实现直流侧电压恒定和有功、无功功率的独立解耦控制。最后,建立Matlab的仿真模型进行仿真分析,仿真结果表明所设计的控制器具有良好的暂态控制性能和较强的鲁棒性。

A nonlinear transient mathematical model of voltage source converter based high voltage direct current （VSC-HVDC） power transmission system in synchronously rotating d-q frame of axes is built. To design the controller for this nonlinear system directly, the approach of state feedback exact linearization is adopted to change the nonlinear mathematical model into the linear one; then utilizing the variable structure-based control method the controllers for rectifying side and inversion side are designed, thus the constant voltage at DC side and independent decoupling control for active and reactive power can be implemented; finally, a Matlab-based simulation model is constructed for simulation analysis of the proposed controllers. Simulation results show that the designed controllers possess satisfied transient control performance and strong robustness.