PHASOR MEASUREMENT UNIT BASED WIDE AREA BACKUP PROTECTION SCHEME FOR TRANSMISSION LINES

Abstract

This thesis proposes an innovative wide area backup protection scheme for untransposed single- or double-circuit transmission lines that can be applied as a substitute for third zone function of distance relay. The proposed scheme is derived based on the transmission line theory and Taylor series expansion of distributed line model parameters taking into account the effect of mutual couplings between the adjacent circuits. For large power network, a binary integer linear programming is utilized for determining the minimal number of PMUs to obtain complete fault observability. Synchronized voltage and current measurements obtained from PMUs are utilized for fault detection, faulty line identification, and fault location. Extensive simulation studies are applied to three-terminal untransposed double-circuit transmission lines and New England 39-bus test system and the simulation results prove that the proposed scheme yields acceptable performance for all simulated