摘要:This article presents an optimal placement method in order to size and sit distributed generation in IEEE 33 bus test system. The algorithm for optimization in this paper is Simulated Annealing. The proposed objective function considers active power losses of the system and the voltage profile in nominal load of system. In order to use Simulated Annealing algorithm, at first, placement problem is written as an optimization problem which includes the objective function and constraints, and then to achieve the most desirable results, Simulated Annealing (SA) method is applied to solve the problem. High performance of the proposed algorithm in mention system is verified by simulations in MATLAB software and in order to illustrate of feasibility of proposed method this optimization in three cases – one DG unit, Two DG units, and Three DG units- will accomplish.