Contactor-Based Simulation Design of an Automatic Transfer Switch and Mains Failure Panel for Power Continuity Systems

Abstract

Reliable electrical power supply is crucial for industrial, commercial, and essential facilities, as mains failures can cause significant operational losses and equipment damage. To address this, Automatic Transfer Switches (ATS) integrated with Mains Failure (AMF) panels are employed to ensure continuous power supply by automatically transferring loads to backup sources such as generators. This study aims to design and simulate a contactor-based ATS-AMF system to evaluate its performance, stability, and monitoring capabilities prior to physical implementation. The methodology involved system design, specification of components, simulation modeling, and performance testing, including input and output voltage verification at Miniature Circuit Breakers (MCBs) and contactors, measurement of current and frequency, and evaluation of operational modes (manual, automatic, and repair). Results indicate that both the PLN main supply and the generator maintain stable single-phase and three-phase voltages within nominal limits, with minimal voltage drop across contactors, confirming proper power transmission. Current measurements under no-load conditions were zero, while frequency remained constant at 50 Hz, meeting operational standards. These findings demonstrate that the contactor-based ATS-AMF system can reliably manage automatic load transfers, ensure uninterrupted and stable power delivery, and provide accurate monitoring, offering an effective and safe solution for backup power systems.