Optimal hourly scheduling of distributed generation and capacitors for minimisation of energy loss and reduction in capacitors switching operations

Now-a-days electric power systems all over the world are undergoing a phase of increased size and complexity due to rising load demand expansion. This situation leads to excessive burden on the power distribution systems posing many challenges before the distribution system utilities. Minimisation of real power loss and maintaining voltage profile are the major requirements for a distribution system apart from cost reduction. Capacitors and tap changing transformers are being conventionally used for maintaining voltage profile along a primary distribution network. When a distributed generation (DG) is incorporated in a distribution system, the problem of efficiently controlling a system becomes more complex. In this study, a novel multi-objective optimisation problem of hourly scheduling of voltage control devices in coordination with a DG is attempted. An efficient particle swarm optimisation technique is used to solve the problem. Another novelty of this work is the use of Newton-based power flow method for evaluation of function value. The algorithm proposed is validated on IEEE standard 33 bus and 69 bus radial distribution systems. The results are encouraging.