Simplified Methodology for EMT Model of Three- Phase Short-Circuit Analysis Study

In the transition toward the utilisation of clean energies, the rise of distributed generations (DGs) leads to the increase of complexity of current power systems, affecting the power protection systems in indirect and direct manners. A study of short-circuit (SC) analysis could be a good approach to analyse the characteristics of the protection system according to the huge transformation. Accordingly, Electromagnetic Transient (EMT) model is commonly used with small discrete time step. The paper proposes a simplified methodology for constructing EMT model to analyse three-phase SC current based on Thevenin-Norton theorem. The complexity of the electrical network is simplified by constructing an equivalent circuit that consists of voltage sources and the network’s impedance components. Accordingly, the time-domain equations for the three-phase SC will be developed and used for analysis to determine the peak current and peak time. For real-world case testing, the CIGRE European Medium Voltage (MV) distribution benchmark system with two operating topologies, radial and loop, is used to validate the simplified methodology with specialised software, DIgSILENT PowerFactory and Typhoon HIL. This investigation brings EMT model back to foundational circuit theory and mathematics problem beyond the use of simulation software that can contribute to teaching and research materials focusing on SC analysis the potential impact that DERs integration may have on the power system protections.