A new model for optimal deployment of remote controlled switches in a radial distribution system using mixed-integer non-linear programming

Enhancement of service quality and reliability is the major concern for the present electricity market. To enhance service reliability different types of protective devices are placed in distribution systems. Remote controlled switches (RCSs) reduces the time to detect, isolate and restore the fault. Moreover it improves the reliability of the system to a great extent. In this paper, a new model has been developed for optimal deployment of RCSs in a radial distribution system (RDS). The formulated problem includes the number and locations of RCSs to be optimally placed in a RDS. The objective of the formulation is to maximize the profit while minimizing cost of RCSs installation, operation, maintenance, outage costs and improvement of reliability indices. Reliability indices which include SAIFI (system average interruption frequency index), SAIDI (system average interruption duration index), CAIDI (customer average interruption duration index), ASUI (average service unavailability index), ASAI (average service availability index) and AENS (average energy not supplied) are evaluated for reliability assessment. Mixed-integer non-linear programming (MINLP) is utilized to solve the formulated optimization problem. The obtained results show that optimal deployment of RCSs results in considerable improvement of reliability indices of a RDS. The proposed formulation has been implemented on 13-node, 58-node and IEEE 123-node radial distribution systems (RDSs) to verify its effectiveness.