Particle Swarm Optimization Based Optimal Power Flow for Volt-var Control

Evolutionary computation (EC) techniques such as genetic algorithms (GAs), utilize multiple searching points in the solution space like PSO. Whereas GAs can treat combinatorial optimization problems, PSO was aimed to treat nonlinear optimization problems with continuous variables originally. Moreover, PSO has been expanded to handle combinatorial optimization problems and both discrete and continuous variables as well. Efficient treatment of mixedinteger nonlinear optimization problems (MINLPs) is one of the most difficult problems in practical optimization. Moreover, unlike other EC techniques, PSO can be realized with only a small program; namely, PSO can handle MINLPs with only a small program. This feature of PSO is one of its advantages compared with other optimization techniques. In this paper, the basic PSO method is combined with Newton’s method, and interior point method for the optimal power flow/volt-var optimization. The results obtained on IEEE 30-bus system showed that the hybrid method based on PSO-IPM gives the best results compared to the other methods. It has been demonstrated that the proposed method can be easily applied to large systems.