Thermal generator scheduling algorithm based on heuristic-guided depth-first search

Abstract

This paper develops an algorithm which is suitable for implementation on computers by a logic programming language, Prolog, for scheduling thermal generators to meet the daily rising system demand and spinning reserve requirement in the operation of power systems. The algorithm is based on the depth-first and heuristic search techniques in artificial intelligence, and an interpretation of the scheduling process as a tree searching problem. Heuristic rules are derived for overcoming the problem of combinatorial explosion in the search space of the scheduling process and for quickly determining the solution schedule having the lowest total excessive generation capacity between the total generation capacity and the combined system demand and spinning reserve. The ramp rate characteristics and crew constraints of generator units together with the system constraint of must-on units are incorporated in the algorithm. The application of the developed algorithm which is implemented by Prolog to schedule ten thermal generators is presented.