Optimal Location of Voltage Sag Monitors in Distribution Networks With DGs Using Network Zoning

With the growing use of sensitive loads and distributed generations (DGs), power quality is of great importance in distribution networks (DNs). Voltage sag is a significant power quality disturbance. Hence, monitoring of the voltages and currents of the network is necessary to identify the voltage sag occurrence and its location. However, installing measuring units at every busbar in very expensive. In this article, an optimal method for locating the voltage sag monitors (VSMs) in DNs is proposed, considering the DGs. The proposed method is based on the DN zoning algorithm that utilizes the matrix of voltage sag transfer coefficients. The optimal number of zones is determined based on the proposed threshold value or the financial limits. Then, in each zone, the electrical center busbar is determined by solving an optimization problem. The electrical center busbar in each zone is chosen as the optimal location of the VSMs. The location, size, type, and control strategy of DGs, and the network structure affect the optimal location of the VSMs. The proposed method is implemented in different simulation scenarios at the IEEE 33 bus test system and the simulation results show the efficiency of the proposed algorithm.