基于主导惯量中心的紧急功率支援方法

Emergency DC Power Support Strategy Based on Dominant Center of Inertia

交直流并联系统中送端交流系统出现故障时,利用直流系统的过负荷能力进行紧急功率支援可缓解功率不平衡状况、提高暂态稳定性。介绍了以暂态过程中发电机组的动能增加为准来度量主要参与机组、形成"主导惯量中心"(DCOI)的紧急功率支援方法。直流线路连接的互联区域电网,暂态下区域电网主导惯量中心间的转速偏差能够保留系统重要的动态信息,用此集成紧急功率支援的控制信号,相比于传统的由本地信息构成的调制信号效果更优。在四川电网的仿真中表明:基于主导惯量的转速偏差能够保留系统重要的动态信息,用此集成紧急功率支援的控制信号,相比于传统的由本地信息构成的调制信号效果更优。在四川电网的仿真中表明:基于主导惯量中心的紧急功率支援方案有效地提高了大扰动下暂态系统的稳定性。

In the case of faults in AC sending-side of AC-DC parallel system,application of emergency DC power support relying on over-load capacity of DC system can mitigate the imbalance of active power and advance the transient stability of AC/DC system.For the DCOI-based emergency power support method,the kinetic energy increase of generating units in transient process is taken as the measurement of major participating units.The regional power network interconnected by DC lines,and the speed differences in the dominant center of inertia can retain important dynamic system information,assembled as the control signals for emergency power support,superior to the traditional modulating signals derived from local information.Sichuan Power Grid has been simulated and the results verify that the DCOI-based emergency power support scheme can effectively improve the stability of the transient system under large disturbance.