Optimization of transmission line planning including security constraints

The authors describe an automatic way of finding the least-cost method of securing a given power system. The objective is to minimize the present cost of building additional lines to make the system secure due to single contingencies, subject to the technical constraints with and without line outages. A second approach to the problem, heuristic in nature, is also illustrated and compared to the results of the first method. All network synthesis is based on the DC power flow model. A six-bus network is used to illustrate the methods, and solutions obtained using a standard mixed-integer linear programming computer package, MIP/370, are given