Reactive power redispatch for loss reduction using a modified power flow jacobian

This study addresses the problem of reactive power redispatch under bilateral power transactions. The proposed approach is to reduce active loss in a critical area, under the voltage collapse point of view, which is identified by the tangent vector technique. A methodology that uses an augmented load flow Jacobian is proposed to redispatch the reactive power and can be easily implemented in ordinary power flow programmes. Tests with the IEEE 14-bus test system and with a real Brazilian-107 bus system are carried out to illustrate the proposed approach. Results obtained by solving an optimal power flow problem are also presented for validation purposes.