Distribution systems reliability improvement using optimal phase balancing and economic analysis

The distribution systems are the most unbalanced part of the power network. Voltage unbalance can cause major problems, such as the abnormal performance of the induction motors with their load increment, the network reliability decrement, and the power losses increment. So, phase balancing should be implemented in the distribution networks through the most effective rephasing strategy. In this paper, the optimal automatic rephasing strategy for the improvement of the distribution system reliability is investigated. Calculations of reliability factors after the rephasing strategy are introduced. Also, the impacts of voltage unbalance on induction motors and their costs are optimized. Generally, this paper focuses on system cost reduction through optimal automatic phase balancing, especially in a smart environment. The proposed optimization model is solved using a self-adaptive modified firefly algorithm (SAMFA). The performance of the SAMFA is compared with the ordinary firefly algorithm (FA), particle swarm algorithm (PSO), and genetic algorithm (GA). The proposed method is applied to the Kheibar feeder in Behbahan, Iran. Simulation studies and results analysis greatly demonstrate the significant economic benefits achieved from this research.