柔性直流输电系统的内模解耦控制研究

Research on Internal Modal Decoupling Control of a Flexible VSC-HVDC

基于电压源型换流器的直流输电技术作为一种新型高压直流输电技术,具有很多技术优点和广阔的应用前景。在d-q同步旋转坐标系下,电压源换流器的直流输电系统数学模型有功电流和无功电流存在耦合,利用内模控制原理对电流内环进行解耦,实现了有功功率和无功功率的独立控制,设计了电流内环控制器,并且给出了控制器参数整定的依据指标。Matlab数字仿真结果表明,该方法可以较好地实现有功和无功的解耦控制,具有较好的动态品质和鲁棒性,验证了控制策略的正确性和有效性。

As a new type of HVDC technology based on voltage source converter, VSC - HVDC has many technical advantages and broad application prospects. A mathematical model of VSC - HVDC system in d - q synchronous rotating coordinate sys- tem is described, but the active current and the reactive current are coupling. The internal model control principle is used to achieve a decoupling of the current inner loop and the independent control of active and reactive power, the inner current loop controller is designed and the basis indicators of controller parameter setting are given. The simulation results with Matlab show that the proposed method can achieve decoupling control of active and reactive power and have good dynamic quality and ro- bustness, which verifies the correctness and validity of the control strategy.