Thesis (M.Eng.)--Chulalongkorn University, 2005

This thesis presents a method for solving a distribution system planning problem, which is aimed to minimize network expansion cost, i.e. investment and variable costs. The variable costs comprise loss cost and reliability costs, representing costs of both supply and demand uncertainties. Practical issues, e.g. cost of investment, line cost, reliability indices, load forecast uncertainty and voltage drop, are also included in our consideration. In addition to the costs of supply side as mentioned earlier, this thesis also takes into account the cost of expected unserved energy of customers for which the uncertainties on both demand and supply sides will be included in the analysis. The obtained expansion plan therefore reflects the optimum overall social cost. A power system reliability evaluation technique is employed to solve a single-stage distribution expansion planning problem. A generalized algorithm is developed, tested, and discussed with twosmall test systems