Non-Iterative, Unique, and Logical Formula-Based Technique to Determine Maximum Load Multiplier and Practical Load Multiplier for Both Transmission and Distribution Systems

Abstract

In recent days, due to the increasing number of electric vehicle charging stations (EVCSs) and additional power consumption by domestic, commercial, and industrial consumers, the overall power system performance suffers, which further degrades voltage profile, reduces stability, increases losses, and may also create a voltage collapse problem. Therefore, it is crucial to predetermine a maximum loadability limit for voltage collapse analysis and a practical allowable extra load for safe and secure operation, keeping the bus voltage within the security limits. To mitigate the problems, unique and innovative formulae such as the maximum load multiplier (MLM) and practical load multiplier (PLM) have been developed to consider line resistance. The determination of actual permissible extra load for a bus enables quick assessment of bus-wise suitable capacities and the number of EVs that can be charged simultaneously in the charging station. The planning engineers can easily settle on the extra load demand by domestic, commercial, and industrial consumers, while maintaining the voltage security constraint. The proposed technique is simple, non-iterative, computationally inexpensive, and applicable to both transmission and distribution systems. The proposed work is tested on a 57-bus transmission system and 69-bus radial distribution system, and the obtained results from the developed formulae are verified by comparing with conventional iterative methods.