Load despatch and PSO algorithm for DED control

The efficient and optimum economic operation, control and planning of generating units have always occupied important positions in the electric power industry. Optimisation is a very essential element in the power system, whether in the design or operational stage, to ensure minimum cost, which is of prime concern. Automatic control for load despatch problem comes in the picture because of bigger size in the interconnection of power generating stations day-by-day and it is carried out by adjusting the various control parameters in the system. Dynamic Economic Despatch (DED) determines the optimal operation of generating units with predicted load demands over a certain period of time with an objective to minimise total production cost while the system is operating within its ramp rate limits. This paper presents DED control with valve point loading effect based on Particle Swarm Optimisation (PSO) algorithm for the determination of the global or near global optimum despatch solution and its solution is compared with Static Economic Despatch (SED). In the present case, load balance constraints, operating limits, valve point loading, ramp constraints and network losses using B-loss coefficients are incorporated. Numerical results for a sample five-unit test system have been presented to demonstrate the performance and applicability of the proposed method.