基于电压源换流器的高压直流输电系统的阻尼特性与阻尼控制

Research on VSC-HVDC Damping Characteristics and Damping Control

利用复数力矩分析方法近似推导了基于电压源换流器高压直流输电(voltage source converter HVDC,VSC-HVDC)系统的电磁力矩,定性分析了VSC-HVDC的快速功率控制可能会导致系统出现电气阻尼变弱或负阻尼现象。在建立包括VSC-HVDC及控制器在内的AC/DC混合系统的动态数学模型的基础上,应用最优控制理论设计了最优阻尼控制器,交直流并联系统数值仿真结果表明该附加阻尼控制方法的有效性。

By use of complex torque analysis method, the electromagnetic torque of voltage source converter based HVDC （VSC-HVDC） system is approximately derived, the phenomena of electric damping decreasing or negative damping in AC/DC transmission system caused by fast power control of VSC-HVDC are quantitatively analyzed. On the basis of establishing a small signal model for AC/DC hybrid power grid in which the VSC-HVDC and its controller are included and by use of optimal control theory, an optimal damping controller is designed. Numerical simulation results of AC/DC hybrid power grid show that the supplementary damping control method is efficient.