中文摘要：

基于电压源换流器（voltage source converter，VSC）和脉宽调制（pulsewidth modulation，PWM）技术的新型高压直流输电（vsc—HVDC）系统，具有与传统高压直流输电（HVDC）相似的有功功率控制能力，同时还具有与静止无功发生器（static synchronous compensator，STATCOM）相似的无功功率控制能力。在VSC-HVDC动态模型的基础上，利用电力系统分析综合程序提供的用户自定义功能（PSASP／UD），实现了含有VSC—HVDC的多机系统动态仿真。以定有功功率控制VSC的有功设定值信号为输入端，VSC—HVDC并列交流输电线路的有功功率为输出端，通过对指定输入下输出端时域响应数据的普罗尼（Prony）辨识，获取了两端口间的等值降阶线性开环模型。并利用该降阶开环模型以及极点配置技术，设计了VSC—HVDC单输入单输出结构的附加阻尼控制器。以修改后的CEPRI-36交直流并列输电系统为例进行了仿真分析，仿真结果表明VSC—HVDC配备该阻尼控制器后，可显著增加系统振荡阻尼，快速恢复系统稳定。

英文摘要：

Based on voltage source converter （VSC） and pulse width modulation （PWM） technology, the VSC based HVDC （VSC-HVDC） transmission system possesses the capability of controlling active power similar to conventional high voltage direct current （HVDC） transmission system as well as that of controlling reactive power similar to static synchronous compensator （STATCOM）. On the basis of dynamic model of VSC-HVDC transmission system and by use of the user-defined function provided by Power System Analysis Software Package （PSASP）, the dynamic simulation of multi-machine power system incorporated with VSC-HVDC is implemented. Taking VSC＇s active power set point as input and active power of VSC-HVDC parallel AC line as output, the reduced-order linear opened-loop model between input and output is obtained by use of the Prony identification of time-domain response data at output port under specified input. Using this reduced-order linear opened-loop model, an additional damping controller for VSC-HVDC with the structure of single input and single output is designed. The simulation of VSC-HVDC transmission system with additional damping controller is performed by modified CEPRI-36 multi-machine power system. Simulation results show that the system damping for low frequency oscillation can be obviously increased and system stability can be rapidly recovered while the additional damping controller is equipped,