Considering Voltage Dips Mitigation in Distribution Network Planning

Voltage dips are disturbances that undermine the quality of supply or, more precisely, the power quality perceived by the customers, often causing heavy economic damages to the end-users. Methods for mitigating voltage dips have been widely investigated in literature, but poor attention has been given to solutions that consider their mitigation at the planning stage. In previous works, the authors have proposed a distribution network planning methodology to deal simultaneously with the network design and the power quality. The optimization algorithm is able to find some convenient solutions to comply with power quality constraints. To reduce the expected number of voltage dips above a threshold established by regulators and to protect the customers, the planner is driven to perform specific actions, as the installation of custom power devices in particular nodes of the network. In this paper, an improved model of dynamic voltage restorer has been developed and implemented in the optimization methodology. Accordingly with this model the effectiveness of the compensation device has been evaluated with the aim at finding the most economical solution to voltage-dip problems. In the paper, examples are provided to showing the impact of voltage dips and their mitigation in distribution planning