Behavior of COTS-Based Equipment Under Ship Mains Supply Frequency Tolerance Requirements

Abstract

The use of commercial off the shelf (COTS) devices have become a preferred strategy in ship system developments. In this work, we investigated the behavior of an uninterruptible power supply (UPS) using COTS-based equipment on a ship's power distribution system. It focuses on the implementation of IEC 60092-101 and STANAG 1008 Ed. 9 frequency tolerance requirements. One of the important benefits of this work is that it can be used as a consideration for the electromagnetic risk of integrating COTS-based equipment in an islanded power system like ships. The voltage and current behavior of the equipment under test were measured and recorded at four different points simultaneously using a multipoint measurement technique. From the analysis, it was found that when the frequency of the mains supply is deviated by 5 % the current at the UPS input is modulated and the maximum current is increased.

The Effect of Ship Mains Supply Frequency Transient on UPS-based Equipment

“…When the operating frequency of the main supply changes or deviates, it causes a difference in operating frequency between the input and output of the UPS (Δf). This difference could lead to amplitude modulation [2] and inaccuracy in the harmonic analysis [7]. Furthermore, this study investigates the effect of a ship's frequency transient tolerance on COTS UPSbased equipment according to STANAG 1008 Ed 9 and IEC 60092-101, which is also a continuity of the previous study [2].…”

“…This difference could lead to amplitude modulation [2] and inaccuracy in the harmonic analysis [7]. Furthermore, this study investigates the effect of a ship's frequency transient tolerance on COTS UPSbased equipment according to STANAG 1008 Ed 9 and IEC 60092-101, which is also a continuity of the previous study [2]. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 812391.…”

“…However, often ship system integrators install commercial off-the-shelf (COTS) UPS into the ship environment. It is unavoidable due to the limited availability of existing product suppliers and the cost to comply with certain marine standards environment differs a lot [2]. This COTS UPS is expected to be compatible with the existing supply voltage and frequency requirement stated in STANAG 1008 Ed.…”

Conducted Emission of a DC Motor Speed Drive: an Approach on Risk Assessment for Ship Application

“…Also, sailors or ship technicians bring often non-military standard-compliant equipment into the warships, such as commercial off-the-shelf (COTS) drills, household equipment, office equipment or rotating machines to support their daily activity in ships. It is inevitable because equipment that meets the specific standard for commercial ships and warships is very costly and sometimes not available in the market [2], [3].…”