基于响应的支路暂态输电能力指数及紧急控制

Response-based Branch Transient Transmission Capability Index and Transient Stability Emergency Control

源网荷结构深度调整,使交直流混联电网受扰动态行为愈趋复杂。电网稳定特性的深刻变化,对稳定态势监测与紧急控制技术提出新的要求。该文首先研究了机组功角摇摆过程中,网络中节点电压幅值与相位在时空上的分布规律,以及不同支路段功率传输的特征;基于网络受扰响应信息,构建一种可表征暂态功角稳定态势、评价互联电网稳定水平的定量指数——支路暂态输电能力(branchtransient transmissioncapability,BTTC)指数,其具备精准性、快速性、单调性和灵敏性等性能优点;基于BTTC指数,提出降低机群暂态功角失稳风险的紧急控制策略。针对实际交直流混联电网,仿真验证了BTTC指数刻画稳定态势及紧急控制策略降低失稳风险的有效性。

The deep adjustment of power supply, power grid and load structure make the disturbance behavior of the interconnected large power grid more and more complex. The profound changes of stability characteristics put forward new requirements for stability situation monitoring and emergency control technology. Firstly, this paper studied the spatial and temporal distribution characteristics of voltage amplitude and phase and the power transmission characteristics of different branches in the process of power angle swing of generators. An index of branch transient transmission capacity(BTTC) was constructed for continuous quantitative evaluation of transient stability, which has the advantages of single modulation of situation representation and criticality of judging instability. Based on the BTTC index, an emergency control strategy to reduce the risk of transient instability was proposed. The effectiveness of BTTC index and emergency control strategy is verified by simulation result got from the HVDC and ac hybrid china southern power system.