交直流电力系统暂态安全稳定在线紧急控制策略并行算法

针对在线策略优化约束和控制措施考虑不足以及计算速度无法满足在线要求等问题,基于参与因子、综合电气距离、无功电压灵敏度及安全稳定裕度,提出了直流系统功率紧急调制、切机、切负荷和局部电网解列的量化控制性能指标和两阶段在线策略优化集群计算方法。在各阶段计算中,依据控制措施性能指标进行措施组合,形成计算任务,按控制代价对计算任务排序形成调度队列,提交集群系统进行并行计算。首先计算暂态功角稳定紧急控制策略,实现直流紧急调制与切机和匹配切负荷的协调;然后,在暂态功角稳定策略的基础上,进行暂态电压和频率安全稳定策略的计算,实现暂态功角稳定控制与暂态电压和频率安全稳定控制的协调。仿真实例验证了算法的有效性。

A Parallel Algorithm for Determining an Online Emergency Control Strategy of Transient Security and Stability for AC-DC Power Systems

In view of insufficient consideration of the online strategy optimization constraining and control measures as well as the calculating speed that cannot meet the online requirements, a control performance index calculating method for DC power emergency modulation, generator tripping, load shedding and partial resection grid islanding is developed based on the participation factors, comprehensive electrical distance, reactive power-voltage sensitivity, and security-stability margin. In addition, a two-stage clustered computing method for online optimization strategy is proposed. At each stage, according to the control performance index, all control measures are combined to form the computing task with the scheduled queue to be submitted to the clustered system for parallel computation. Firstly, the transient angle stability emergency control strategy is computed to realize coordination among emergency DC modulation, generator tripping and load shedding. Secondly, on the basis of the optimal transient angle stability control strategy, the emergency control strategy of transient voltage and frequency security and stability is computed to realize the coordination between the transient angle stability with the security and stability of transient voltage and frequency. The simulation results have verified the validity of the proposed computing method. This work is supported by State Grid Corporation of China, Major Projects on Planning and Operation Control of Large Scale Grid (No. SGCC-MPLG001-003-2012).