A method of determining the combination of outage works

In a power system, maintenance works are needed to secure stable power supply, which inevitably causes the outage of power facilities. During maintenance works, a high level of power system reliability must be secured. So far, the outage planning of an electric power system has been made by planning engineers with great experience. However, since the amount of information necessary to handle outage work planning is prohibitively large, it has become difficult to adjust the information by human experts. In order to automatically do it, the authors propose an approach to determine the combination of outage works by using numerical computation methods such as the DC load flow. This approach makes use of an index computed from a quantity of overloaded lines in case of any outage of two lines or a generator. The proposed approach has been applied to a part of the 110 kV transmission line systems of the Chugoku Electric Power Company.