Dynamic Load and Storage Integration

Modern technology combined with the desire to minimize the size and weight of a ship’s power system are leading to renewed interest in more electric or all electric ships. An important characteristic of the emerging ship power system is an increasing level of load variability, with some future pulsed loads requiring peak power in excess of the available steady– state power. This inevitably leads to the need for some additional energy storage beyond that inherent in the fuel. With the current and evolving technology, it appears that storage will be in the form of batteries, rotating machines, and capacitors. All of these are in use on ships today and all have enjoyed significant technological improvements over the last decade. Moreover all are expected to be further enhanced by today’s materials research. A key benefit of storage is that, when it can be justified for a given load, it can have additional beneficial uses such as ride-through capability to restart a gas turbine if there is an unanticipated power loss; alternatively, storage can be used to stabilize the power grid when switching large loads. Knowing when to stage gas turbine utilization versus energy storage is a key subject in this paper. The clear need for storage has raised the opportunity to design a comprehensive storage system, sometimes called an energy magazine, that can combine intermittent generation as well as any or all of the other storage technologies to provide a smaller, lighter and better performing system than would individual storage solutions for each potential application.Center for Electromechanic

Modeling Fault Propagation Paths in Power Systems: A New Framework Based on Event SNP Systems With Neurotransmitter Concentration

To reveal fault propagation paths is one of the most critical studies for the analysis of power system security; however, it is rather dif cult. This paper proposes a new framework for the fault propagation path modeling method of power systems based on membrane computing.We rst model the fault propagation paths by proposing the event spiking neural P systems (Ev-SNP systems) with neurotransmitter concentration, which can intuitively reveal the fault propagation path due to the ability of its graphics models and parallel knowledge reasoning. The neurotransmitter concentration is used to represent the probability and gravity degree of fault propagation among synapses. Then, to reduce the dimension of the Ev-SNP system and make them suitable for large-scale power systems, we propose a model reduction method for the Ev-SNP system and devise its simpli ed model by constructing single-input and single-output neurons, called reduction-SNP system (RSNP system). Moreover, we apply the RSNP system to the IEEE 14- and 118-bus systems to study their fault propagation paths. The proposed approach rst extends the SNP systems to a large-scaled application in critical infrastructures from a single element to a system-wise investigation as well as from the post-ante fault diagnosis to a new ex-ante fault propagation path prediction, and the simulation results show a new success and promising approach to the engineering domain

ESRDC ship notional baseline Medium Voltage Direct Current (MVDC) architecture thermal simulation and visualization

This work presents a fast visualization and thermal simulation tool developed as part of the Electric Ship Research and Development Consortium (ESRDC) funded by the Office of Naval Research (ONR) that is capable of providing quick responses during early stages of ship design. The tool allows for the visualization of thermal and electrical loads, and equipment locations and other variables of interest in the all-electric ship, proceeding to the computation of the resulting whole ship temperature and relative humidity distribution. For that, a previously developed simplified physical model [1-3] -- which combines principles of classical thermodynamics and heat transfer, resulting in a system of three-dimensional differential equations which are discretized in space using a three-dimensional cell centered finite volume scheme -- is enhanced to include fresh and sea water cooled systems throughout the ship. Therefore, the combination of the proposed simplified physical model with the adopted finite volume scheme for the numerical discretization of the differential equations is called a volume element model (VEM). A 3D simulation is performed in order to determine the temperature distribution inside the ship for the baseline Medium Voltage Direct Current (MVDC) architecture, and representative operating conditions are analyzed. VisIt visualization tool [4] is used to plot the results.United States. Office of Naval Research (Grant N00014-08-1-0080

The safety case and the lessons learned for the reliability and maintainability case

This paper examine the safety case and the lessons learned for the reliability and maintainability case

A Review and Comparison of Ship Power Simulation Methods

Safe, secure and efficient clean sea shipping proposed by the IMO requires the development of the appropriate design, operating knowledge and tools for assessing energy efficient design and operation of ships. A brief overview of the methods and models of ship power management simulation shows the advantages and disadvantages of representative models. This review includes a comparison of different simulation methods, which implies different models, with the aim of optimizing the production of electricity on board, emission reductions and improved energy efficiency. In addition, the recommended technical solution for contributing to energy efficiency on board is given

Intellectual Inventory

http://deepblue.lib.umich.edu/bitstream/2027.42/79504/1/1984_Intellectual_Inventory.pd