负荷中心含微电网的小干扰电压稳定性分析

Analysis of small disturbance voltage stability of the load center with microgrid

分析负荷断面的小干扰电压稳定时,当负荷中心包含地方电厂,这些负荷中心电源的动态特性对受端电网的电压稳定有着显著的影响。使用包含小电源的负荷模型,运用基于潮流的小干扰稳定分析法,研究小电源为汽轮发电机时其对负荷断面电压稳定的影响,利用模态分析法获得评价电压稳定的指标,并深入探讨了机组的励磁和调速系统的增益环节与电压稳定指标的关系。结果表明负荷中心的汽轮发电机组对电压稳定有着积极作用,仿真结果验证了该结论的正确性。

When analyzing cross-section of a load of small disturbance voltage stability, it is found that if local power plant is in load center, the small power has a significant impact on voltage stability of receiver grid. This paper uses the load model containing small power and the analysis method of small disturbance based on power flow to study the influence of local power that is taken as the turbo-generator unit on voltage stability of load cross-section. The modal analysis method is used to obtain voltage stability index and to deeply discuss how the amplification factors of the excitation system and speed control system of the unit affect the voltage stability index. Results show that the synchronous generator in load center has a positive effect on voltage stability. Simulation results indicate the validity of the conclusions.