【摘要】 针对目前基于电压源换流器型高压直流输电(VSC-HVDC)工程中常采用的定有功功率-定无功功率(P-Q)控制模式,建立了基于P-Q控制模式的VSC-HVDC系统的小干扰数学模型,分析了整流和逆变工作状态下交流系统强度、等值阻抗角、无功功率运行点对VSC-HVDC稳定性的影响;提出了一种综合考虑系统小干扰稳定性和电压安全运行约束的临界运行短路比(CSCR)指标,可以定量评估不同运行工况下VSCHVDC系统的安全稳定运行极限,为VSC-HVDC系统的安全稳定运行提供理论依据;最后在PSCAD/EMTDC下搭建仿真模型,验证了分析结论的正确性。更多还原

【Abstract】 The constant active power-reactive power(P-Q)control mode is widely used in voltage source converter based high voltage direct current projects. To evaluate the small-signal stability of the VSC-HVDC system based on P-Q control mode,a small-signal model was deduced. Based on this model,the impact of AC system strength,equivalent impedance angle and reactive power operating points on the stability of VSC-HVDC working as rectifier or inverter were analyzed. The critical operating short circuit ratio(COSCR)satisfied both the small-signal stability and safe voltage operating constraint were investigated,which provided useful information to evaluate the operating limits of VSC-HVDC based on P-Q control mode. Finally,the analysis results were verified by a detailed VSC-HVDC model built in PSCAD/EMTDC.更多还原