On electric warship power system performance when meeting the energy requirements of electromagnetic railguns

Abstract

This paper investigates the ability of a gas turbine alternator to provide power to an electromagnetic (EM) railgun in surface combatants whilst simultaneously maintaining acceptable levels of power quality for other consumers. Following the justification of the investigation and a description of the research methods, which includes a proposed EM railgun charging control system, this paper discusses simulated results obtained from a validated power system model for both single shot and salvo operations and identifies factors that limit the rates of fire in each case. The findings from the investigations suggest that a large gas turbine alternator is able to maintain quality of power supply within acceptable limits for the majority of EM railgun operations. However, the transient quality of power supply limits was found to be exceeded for heavy firing rates but would remain within tolerable limits as defined for exceptional loads by North Atlantic Treaty Organization (NATO) standardization agreement (STANAG) 1008 Edition 9. A method to increase the maximum rate of fire whilst maintaining the quality of the power supply within acceptable limits is investigated by increasing the size of the energy storage device and retaining a residual charge. The paper concludes by suggesting that the EM railgun system could be integrated into the ship's electrical system without the need for any additional prime movers to achieve rates of fire commensurate with a surface combatant's requirements.

Transient performance of alternatively fueled internal combustion engines for naval applications

“…The third load profile represents the load demand of an electromagnetic railgun firing three shots at the rate of one shot per 6s and an initial charge time of 17.5s according to [52]. The load profile and the results are given in Figure 8.…”

An architectural framework for distributed naval ship systems

“…After the set of possible solutions is narrowed using low fidelity simulation, high-fidelity analysis of specific systems can be targeted. For instance, high-fidelity analyses have been performed to analyze the tradeoff between AC and DC electrical distribution systems (Chalfant et al, 2010), understand the impact of electrical weapons on power supply stability (Whitelegg et al, 2015), but also to understand the relationship between propulsion and maneuvering systems (Altosole et al, 2010). However, high-fidelity models often require a significant jump in design detail and can take up valuable time to model in early stage design, especially at a point in time where the chosen design solution has yet to emerge.…”

Dynamic Modeling of a Hybrid Propulsion System for Tourist Boat

“…Thanks to the increasing power density of lithium-ion battery technologies [16], HPS coupled with ESS has become a realistic option for many maritime applications. For example, real HPS applications can be found in naval vessels [17,18], offshore vessels [19,20], research vessels [21], yachts [22], ferries [23,24], towing vessels [25].…”

“…Consequently, ESS adoption (i.e., batteries, super capacitors, etc.) can provide peak shaving, load smoothing, frequency control, improved quality of power supply and, above all, can enable to switch off all internal combustion engines for a limited period [18,26] reducing noise and pollutant emission. Moreover, batteries can also provide back-up power during failures of diesel generators [24].…”