Bi-Objective Hydroelectric Optimal Dispatch under Electricity Deregulated Environment

Hydroelectric units play important roles within the power system security due to their fast response characteristics. Within the present operation strategy of the Taipower, both hydro and thermal units are concurrently dispatched under the Power Dispatch Center in order to raise the system security. However, after the power industry deregulation in Taiwan, many independent power producers (IPPs) join the power market. The operation strategy of IPPs is mainly concerned with electricity pricing competition rather than system security consideration. Therefore, with the increasing of IPPs, the conventional hydro-thermal coordination of Taipower faces a new challenge of increased security risk. This paper proposes a bi-objective hydroelectric optimal dispatch approach to improve system security under electricity deregulated environment. In the work, the bi-objective functions take system security risk minimization as well as thermal costs minimization into account to enhance system security