Abstract:

In order to improve the calculation efficiency and accurately identify the saddle-node bifurcation point （SNBP） and the limit-induced bifurcation point （LIBP）, an improved continuous power-flow （CPF） algorithm is presented, in which the calculation process of P-V curve is divided into three stages, and the calculation with high accuracy is accelerated by matching a correct method according to the characteristics of the continuous power-flow calculation in each stage. Then, based on the analysis of the mechanism and characteristics of LIBP, a criterion to identify the LIBP is proposed. Moreover, the proposed three-stage CPF algorithm is used to identify the bifurcation points and to judge the key devices inducing the LIBP as well as the voltage/reactive power constraint exchange point closely related to LIBP. Numerical simulation and comparison are finally performed on IEEE 14-bus and 118- bus systems. The results verify the rationality and effectiveness of the proposed algorithm.

Key words: limit-induced bifurcation point, saddle-node bifurcation point, type identification, improved continuous power-flow algorithm