A novel preventive islanding scheme of power system under extreme typhoon events

Abstract

Extreme typhoon events often damage transmission lines and towers, causing large-scale cascading faults, and even collapsing the power system. In this paper, a preventive islanding scheme under extreme typhoon events is proposed to prevent the occurrence and propagation of cascading faults. Firstly, the outage probability of transmission branches under typhoon events is modeled and evaluated by employing the Batts typhoon model and fragility curve. Then, based on power flow calculation, a preventive islanding criterion is proposed to describe the damage degree of typhoon events to the power system and provide a decision-making basis for preventive islanding. Besides, a preventive islanding surface searching algorithm based on the combination of nodes with active power balance is proposed to minimize the load shedding of the system, and the vulnerable branches are selected as the obligatory splitting branches. Then, an optimal load shedding model is proposed to minimize the voltage deviation of each node in the islands by optimizing the reactive power generation and load shedding distribution in each island. Finally, a staged preventive islanding process under extreme typhoon events is proposed based on the time sequence of typhoon development. The simulation tests of the IEEE 39-bus and 118-bus systems under real typhoons indicate that the preventive islanding scheme proposed in this paper can effectively prevent the occurrence of cascading faults and reduce the load loss of the power system under an extreme typhoon event.