Identifying single and double edge cutsets in power networks

Single edge cutsets constitute the most vulnerable spots of a given network due to the possibility of islanding in case of their outage. Double edge cutsets have recently been shown to also have a vulnerability which was that their parameter errors could not be identified using conventional measurements unless phasor measurement units (PMUs) were introduced at appropriate locations. The main motivation of this paper is to address this vulnerability. As a first step, the paper investigates a practical and efficient way of identifying such cutsets. The proposed method is based on factorization of the reduced incidence matrix of a system. The problem is solved without enumerating all the cutsets of a network, which is the main disadvantage of existing algorithms especially when the system is large. The method along with its implementation details are presented in the paper. Numerical examples are included to illustrate the proposed procedure.