Algebraic-graph method for identification of islanding in power system grids

In this paper, a new algebraic-graph method for identification of islanding in power system grids is proposed. The proposed method identifies all the possible cases of islanding, due to the loss of a equipment, by means of a factorization of the bus-branch incidence matrix. The main features of this new method include: (i) simple implementation, (ii) high speed, (iii) real-time adaptability, (iv) identification of all islanding cases and (v) identification of the buses that compose each island in case of island formation. The method was successfully tested on large-scale systems such as the reduced south Brazilian system (45 buses/72 branches) and the south-southeast Brazilian system (810 buses/1340 branches).

► A new, fast and reliable algebraic-graph method for islanding analysis is proposed.
► A comprehensive theoretical foundation for the proposed method is presented.
► The method is based on the factorization of the bus-branch incidence matrix.
► The buses that compose each island are easily identified by factorization paths.
► A single factorization suffices to check islanding for the N-1 criterion.