Transformer tap estimation using hybrid particle swarm optimization

State estimation has become one of the main computing tasks of energy management system in power networks. However, little emphasis has been given to developing state estimator capable of handling discrete operating and control variables such as transformer tap used for voltage control. This paper proposes a practical method for state estimation including transformer´s tap estimation with discrete values using a hybrid particle swarm optimization (HPSO) technique. The proposed method is tested on IEEE 14 Bus system model where it has successfully estimated the transformer tap value.