Decentralised security constrained DC-OPF of interconnected power systems

A method for the decentralised solution of the security constrained optimal power flow (SCOPF) problem in large interconnected power systems is presented. The method decomposes the overall SCOPF problem of a multi-area system into independent SCOPF subproblems, one for each area. The solutions of the SCOPF subproblems of the different areas are co-ordinated through a pricing mechanism until they converge to a reduced scope central SCOPF solution. The prices used for the co-ordination of the subproblem solutions are the prices of electricity exchanges between adjacent areas. The reduced scope SCOPF of a multi-area power system is a SCOPF with a reduced set of security constraints, in which the effects of contingencies outside an area on monitored elements within the area are ignored. Test results from the application of the method to the IEEE three-area RTS-96 and to the Balkan power system are presented.