Amir Bagheri - Zanjan University
Yadollah Kordloo - Zanjan University

Distributed generation (DG) has provided new options in the design of electric networks. In this paper, the presence of distributed generation is regarded as an alternative for supplying the load of subtransmission system. The effects of DG on expansion planning of subtransmission system such as costs and energy loss have been mathematically modeled. The fixed and variable costs of plan are formulated in the model. This model gives the optimal capacity of substations; optimal location and capacity of DGs as well as optimal configuration of subtransmission lines satisfying the reliability and system operational constraints and considering the loss. The proposed objective function and its constraints compose an optimization problem which is solved using Decimal Codification Genetic Algorithm (DCGA) and Linear Programming (LP). The effectiveness of the proposed method is investigated by its application on the real subtransmission system of Zanjan Electric Company and the results are compared with expansion planning of the same system without the use of distributed generation.

Distributed generation, expansion planning, genetic algorithm, linear programming,subtransmission system