A fast integer algorithm for observability analysis using network topology

An integer algorithm for determining the observability of a power system network with its linearized state estimator model is presented. By using some properties of the allocation of the flow and injection measurements and the network topology, the algorithm manipulates only integer numbers in the measurement Jacobian matrix. Theorems that determine the rank of the special kinds of matrices are proposed to speed up the observability analysis. There is neither manipulation of real numbers nor a complicated combinatorial problem involved in the proposed algorithm. Therefore, it is much simpler and the speed for observability analysis is much faster. Moreover, no numerical problems are encountered. The design and the test results of the algorithm are reported.<>