E. A. Walters, C. E. Lucas, J. Jatskevich, O. Wasynczuk, PC Krause and Associates, Inc; P. T. Lamm, U.S. Air Force Research Laboratory; T. Neeves, Naval Surface Warfare Center ABSTRACT (Oleg has slide presentation.) American Society of Naval Engineers Symposium Harnessing the Power of Technology for the Warfighter, September 17, 2003, Bloomington, IN.
Read MoreDistributed Heterogeneous Simulation of Naval Integrated Power System
C. E. Lucas, E. A. Walters, J. Jatskevich , PC Krause and Associates, Inc; O. Wasynczuk, Purdue University; P. T. Lamm, U.S. Air Force Research Laboratory; T. E. Neeves, Naval Surface Warfare Center In this paper, a powerful technique of simulating large-scale dynamical systems is applied to a naval integrated power system. This approach enables the overall system simulation to be formed as the dynamic interconnection of interdependent simulations, each representing a specific electrical, mechanical, hydraulic, and/or thermal component/subsystem. Each simulation may be developed independently using possibly different commercial-off-the-shelf simulation programs thereby allowing the most suitable language or tool to be used based on the design/analysis needs. The simulation paradigm provides a structure that offers a convenient means of implementing simulations utilizing single-, multi-, or parallel-rates integration approaches as well as any combination thereof. Specifically, each component can be simulated using a time-step and integration algorithm that is best suited for that subsystem. The integrated power system is an advanced naval electric power system that includes a zonal dc electric distribution system and an integrated electric generation and propulsion system. The composite system simulation is implemented on a three-computer network of personal computers by interconnecting simulations of the constituent subsystems. In addition to the aforementioned advantages, it is shown that significant improvements in computational speed are achieved using this approach. Proceedings American Society of Naval Engineers Electric Machine Technology Symposium, January 27- 29, 2004, Philadelphia,...
Read MoreAn Efficient Multi-Rate Simulation Technique for Power Electronic-Based Systems
S. D. Pekarek, O. Wasynczuk, Purdue University; E. A. Walters, J. V. Jatskevich, C. E. Lucas, N. Wu, PC Krause and Associate, Inc; P. T. Lamm, U.S. Air Force Research Laboratory A novel multi-rate method of simulating power-electronic-based systems containing a wide range of time scales is presented. In this method, any suitable integration algorithm, with fixed or variable time-step, can be applied to the fast and/or slow subsystems. The subsystems exchange coupling variables at a communication interval that can be fixed or varied dynamically depending upon the state of the system variables. The proposed multi-rate method is applied to two example power systems that include power-electronic subsystems. Increases in simulation speed of 183-281% over established single-rate integration algorithms are demonstrated. IEEE Transactions on Power Systems, vol. 19, no. 1, February 2004, pp....
Read MoreDistributed Heterogeneous Simulation, a New Paradigm for Simulating Integrated Naval Power Systems
C. E. Lucas, E. A. Walters, J. Jatskevich, O. Wasynczuk, PC Krause and Associates, Inc; P. T. Lamm U.S. Air Force Research Laboratory; T. E. Neeves, Naval Surface Warfare Center A new paradigm for simulating large-scale dynamical systems is described and applied to an integrated naval power system. This approach enables the overall system simulation to be formed as an interconnection of interdependent dynamic simulations, each representing a specific electrical, mechanical, hydraulic, and/or thermal component/subsystem. Each simulation may be developed independently using possibly different commercial off-the-shelf simulation programs thereby allowing the most suitable language or tool to be used based on the design/analysis needs. The proposed simulation paradigm is applied to an advanced naval electric power system that includes a zonal dc electric distribution system and an integrated electric generation and propulsion system. The composite system simulation is implemented on a three-computer network of personal computers by interconnecting simulations of the constituent subsystems. It is shown that significant improvements in computational speed are achieved using this approach. WSEAS/IASME Transactions, issue 3, vol. 1, July 2004, pp....
Read MoreSynchronous Generator-Rectifier Average-Value Modeling for a Naval Electric Power System
Juri Jatskevich, University of British Columbia; E. A. Walters, C. E. Lucas, PC Krause and Associates, Inc. A prototype Integrated Power System that is representative of advanced power systems of future warships is considered. This system is comprised of an AC Generation and Propulsion System as well as a DC Zonal Electrical Distribution System. Obtaining accurate average-value models of individual subsystems that can be used for extracting the input/output impedance as well as for increasing the simulation speed of the respective models. In this paper, a parametric approach for developing a dynamic average-value model of a generator-rectifier subsystem is presented. The method initially requires a detailed switched model from which the rectifier/dc-link dynamics are captured using numerical averaging; however, the resulting model is continuous and computationally efficient. The developed average-value model is compared against measured and detailed simulation results and is shown to be very accurate in both the time- and frequency-domains. A 74-fold increase in simulation speed is achieved. WSEAS/IASME Transactions, issue 3, vol. 1, July 2004, pp....
Read MoreDistributed Simulation of an Uninhabited Aerial Vehicle Power System (SAE Paper) and Distributed Simulation (Aerospace Engineering)
Scott Graham, Ivan Wong, Won-Zon Chen, Alex Lazarevic, Keith Cleek, Northrop Grumman Corporation ; E. A. Walters, C. E. Lucas, O. Wasynczuk PC Krause and Associates, Inc; Peter Lamm, U.S. Air Force Research Laboratory Future Air Force intelligence, surveillance, and reconnaissance (ISR) platforms, such as high-altitude Uninhabited Aerial Vehicles (UAV), may drastically change the requirements of aircraft power systems. For example, there are potential interactions between large pulsed-power payloads and the turbine engine that could compromise the operation of the power system within certain flight envelopes. Until now, the development of large-scale, multi-disciplinary (propulsion, electrical, mechanical, hydraulic, thermal, etc.) simulations to investigate such interactions has been prohibitive due to the size of the system and the computational power required. Moreover, the subsystem simulations that are developed separately often are written in different commercial-off-the-shelf simulation programs. In this paper, a new technique useful for the numerical simulation of large-scale systems to overcome these obstacles, known as Distributed Heterogeneous Simulation (DHS), is utilized to form a dynamic system-level simulation of a high-altitude, long-endurance UAV-type of power system. This system includes detailed dynamic models of a turbine engine, high- and low-spool generators, and payloads. Although not necessary, all of the component models for this system were developed within the same simulation environment, specifically with MATLAB/Simulink. This enabled a single-computer integrated system model and a distributed computer system simulation to be formed thereby allowing for a direct comparison of simulation accuracy and computational performance for the two simulation approaches. From this comparison, it was determined that by distributing the system simulation across three computers, a 21-fold increase in simulation speed could be realized while producing nearly identical results. 2004 SAE Power Systems Conference, November 2-4, 2004 Paper #2004-01-3193 and Aerospace Engineering, November 2004,...
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