A new heuristic method for solving multi-period economic dispatch for thermal power plants was proposed.The dynamic programming method was applied to obtain the optimal start and stop status of each unit which was to be started and the corresponding start and stop cost which satisfied the cramping constraint under system load condition
thus to put the unit with the highest efficiency into service.Then
for the thermal power units whose start and stop status was certain
the optimal economy distribution that satisfying the system constraint was conducted.The simulation results showed that
this new heuristic approach overcame the problems appeared in priority list method
like difficult to obtain the unit start and stop cost
insufficient influence of cramping constraint on unit priority.It is practicable and effective.