The issue of unit commitment is one of the most important economic plans in power system. In modern and traditional power systems, in addition to being economical of the planning, the issue of security in unit operation is also of great importance. Hence power system operation confronts units’ participation and input considering network security constrains. The issue of units’ participation is defined as an optimization problem aimed at determining units' on or off condition and optimized level of units’ production تفاصيل المقالة