Optimisation of capacitor installations in distribution systems

Installation of reactive-power sources in the form of static capacitor banks is usually resorted to in distribution systems to reduce the energy loss and to achieve any required voltage correction. In this paper, the minimisation of the annual cost of energy loss and the annual cost of capacitor installation is first formulated as a time-dependent optimisation problem. The specific characteristics of distribution systems and the cyclic nature of the load variations permit the reformulation of the problem as a static quadratic programming problem.