Economic Design of Substation Grounding Grid using ETAP Software: A Case Study of 2 x 500 MVA Galang Substation

Abstract

Substation grounding purpose is to secure the safety of personal that are in the vicinity and provide protection of the equipment when short circuit faults. The grounding grid design is an important factor in a substation for fulfilling standard requirements formulated by IEEE Std. 80. Commonly, substation grounding is grid configuration or combination of grid and rod. This study is designing a substation economically by considering the length of rod conductor used. Some grid configuration models were used for analyzing viz. rectangular shape, T-shape and L-shape. The models were compared with the existing design in the Galang substation for finding the minimum conductor length. The grid grounding of the Galang substation is the rectangular shape. By using ETAP package software, the important parameters in design substations such as step voltage, touch voltage for 50 kg body weight can be obtained. The parameters must fulfill the IEEE std. 80-2013 as a safety requirement for designing of the substation. From various configurations were applied, all the shapes models meet the IEEE Std. 80, but T-shape is the most economical design based on the conductor length used.