Gradient-Free Stochastic Sensitivity Analysis of the Shipboard Power System

Sensitivity analysis results are useful both for the early design stage – where the parametric space can be substantially reduced – but also in operating conditions, e.g. of the future electric ship, resulting in reduced operational costs and increased reliability. Here we discuss variance-based methods to analyze the sensitivity of stochastic electro-mechanical systems with multirate dynamics. We present results for an illustrative example and for a model of an integrated power system.United States. Office of Naval Research (N00014-02-1-0623); United States. Office of Naval Research (N00014-07-1-0846); Massachusetts Institute of Technology. Sea Grant College Program (NA060AR4170019 NOAA/DOC

Design of the All-Electric Ship: Focus on Integrated Power System Coupled to Hydrodynamics

We present a detailed model of the integrated power system coupled to hydrodynamics that allows us to study global sensitivities in the All-Electric Ship. A novel element of our formulation is the stochastic modeling of the coupled system to account for uncertainty in the parameters or operating conditions. This new computational framework is applied to a model of the DDG- 51 destroyer that involves a 19 MW 15-phase induction machine and an indirect field oriented controller. In particular, we simulate extreme events corresponding to propeller emergence and firing of pulsed power weapons.United States. Office of Naval Research (N00014-02-1-0623 ESRD Consortium); United States. Office of Naval Research (N00014-07-1-0846); Massachusetts Institute of Technology. Sea Grant College Program (NA060AR4170019 NOAA/DOC

A Design for the Interface Between a Battery Storage and Charging Unit, and a Medium Voltage DC (MVDC) Bus, as Part of an Integrated Propulsion System (IPS) in the All Electric Ship (AES)

Abstract In this paper we present the design of a rechargeable battery storage device for use in an all-electric ship. The purpose of this device is to provide power of predictable quality to selected equipment. In addition a recharging unit is proposed for recharging the battery from the ship's electric bus

Integrated simulation framework for crash back operation

We formulate a modeling and simulation framework that integrates models of an all-electric ship (AES) with ship and propeller hydrodynamic models. In particular we present the first simulation study about the transient behavior of the propulsion system of AES during crash stop and backing maneuvers. A time domain model of all electric propulsion system of a notional destroyer has been coupled with a simplified transient model of the hull and propeller hydrodynamics. The integrated power system of the integrated power system (IPS) includes all main elements of the chain, i.e. from power generators to control units down to frequency controlled electric motors. The simplified unsteady hydrodynamic model of the hull and twin shaft lines with fixed pitch propellers is based on semi-empirical quasi static data corrected with complimentary CFD simulations. The transient behavior of the electrical power distribution and motor control are analyzed and the relevant implications that these kind of violent transient maneuvers have on the engineering of the main electrical components are outlined in the paper. \ua9 2012 Simulation Councils, Inc