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Following the theory and method of the 'same‐phase power supply scheme', as declared in United States and Taiwan patents, a novel power supply method is proposed to reduce damage to users when the supply power is in shortage. This paper proposes using the equivalent model function blocks, as built by MATLAB/Simulink, for simulations of the probable line‐to‐line and single line‐to‐ground faults in a distribution system when the power supply mode is switched from 'normal' to 'same‐phase'. The simulation results prove that, when the power supply is switched to the 'same‐phase' power supply mode, all the short‐circuit fault currents are a little lower than that in the 'normal' power supply mode, and the maximum difference is less than 3%. Therefore, when the supplying power of the system is in shortage or the power distribution system has a short‐circuit fault between phase lines, the system can be directly switched to the 'same‐phase' power supply mode and can continue supplying power to the essential and basic loads for life‐support and people's livelihoods. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

There is growing concern regarding air pollutants (NOx, SOx, and PM) and carbon emissions from ocean-going vessels in harbor areas and the role of high-voltage shore connection (HVSC) systems in mitigating these emissions during vessel berthing. The HVSC operates as a TN grounding system in humid environments, and it needs a proper grounding design to ensure safety when faults occur. This article intends to examine the overvoltage resulting from fault currents and its implications for the safety of operators when a single line-to-ground fault takes place within the design of HVSC grounding systems. The assessment is carried out by employing actual scenarios and parameters from a container berth at Kaohsiung Harbor in Taiwan. Considering site conditions, such as the wet ground surface, human body resistance, and electric shock duration, the tolerable safe voltage level is derived using IEEE Std. 80 and IEC 60479-1. Based on the shore power system grounding architecture specified in IEEE/IEC 80005-1, an equivalent circuit model is constructed to calculate the fault currents using symmetrical component analysis. The actual touch voltages generated in various locations are analyzed under scenarios of connecting or disconnecting the equipotential bonding between the ship and the shore using neutral grounding resistor (NGR) designs. This article delves into the scenarios of electric shock that may occur during the operation of an actual container ship's shore power system. It evaluates whether various contact voltage values exceed current international standards and verifies the grounding design and safety voltage specifications of IEEE/IEC 80005-1. According to the results of this study, the use of NGR and protective earthed neutral (PEN) conductors in HVSC is crucial. This can limit fault currents, reduce touch voltage, and ensure the safety of personnel and equipment. Therefore, ensuring and monitoring equipment conductors and adopting NGRs of appropriate sizes are crucial elements in maintaining electrical safety in HVSC systems. [ABSTRACT FROM AUTHOR]