Heuristic curve-fitted technique for distributed generation optimisation in radial distribution feeder systems

Introducing distributed generation (DG) in a distribution network has considerable advantages such as reducing power loss and cost, environmental friendliness, voltage improvement, postponing system upgrades and enhancing system reliability and continuity of service. Practical application of the DG, however, proves difficult. Social, economic and political factors affect the final optimal solution. Solution techniques for DG deployment rely on optimisation methods. The technique proposed here finds the optimal location and size of the DG to minimise the total system power loss for radial distribution feeder systems by solving two independent sub-problems: (i) location and (ii) size. A sufficient sensitivity test for the first problem is suggested. Determining the optimal DG size is done using a new heuristic curve-fitted technique that reduces the search-space by selecting fewer DG-tests. Four DG sizes, which are carefully selected based on the system´s total load demand percentages, are used to determine the optimal solution. To validate the proposed technique, the 33-bus and 69-bus feeder systems are examined and the results obtained by the presented technique are compared with those obtained using other competing methods.