A viable controlled splitting strategy to improve transmission systems resilience against blackouts

摘要

An effective strategy for intentional islanding of a transmission system is proposed in this paper to boost its resilience under low-probability high-impact events such as man-made attacks and natural disasters, which can cause catastrophic blackouts. This strategy considers two main aspects of islanding, i.e. time and scheme. To realize the appropriate time that the system need to be intentionally islanded, a new algorithm based on analysis of the rotor angles of its generators is first presented to distinguish coherent groups of the generators. The main advantage of this algorithm is its independence to the predefined degree of coherency and number of the groups. The information obtained by grouping the generators is then used to compute a new defined indicator, whose sign change specifies the islanding time. To decide about the lines that must be disconnected for fulfillment of the islanding scheme, the initial islands are first formed by tracing the active power produced by the generators. Then, the intended scheme is devised by solving a binary linear programming (BLP) problem that minimizes the disruption of the power transferred between these islands. Comparing the proposed scheme with some existing ones shows that the proposed strategy splits two IEEE test systems into stable islands with a better voltage profile and lower imbalance between the active power generation and demand by disconnecting fewer lines, which have smaller amounts of the power flows.