Type of Awards: SBIR Phase I and Phase II Subcontractors: Purdue Contract Numbers: W56HZV-04-C-0126 and W56HZV-04-C-0713 Agency: U.S. Army Tank Command Status: Completed Periods: 3/2/04 to 9/2/04 and 11/4/04 to 5/4/07 Principal Investigator: C. E. Lucas Abstract: Complex engineered systems such as the power systems of tactical vehicles and advanced weapon systems involve a broad spectrum of technologies and interactive subsystems that must work synergistically. Due to the interdependencies between subsystems and he ever present re-design process, it is becoming increasingly important to establish a flexible virtual prototyping design and analysis infrastructure that facilitates the investigation of interactions between subsystems and promotes the collaboration between individual groups and organizations involved in the design, analysis, and/or development of complex “systems of systems.” Moreover, this type of simulation infrastructure would provide system integrators and program managers with a rapid and easy-to-use means of establishing proof-of-concept for new systems, evaluating competitive system configurations or architectures at a system level and, after the candidate architecture is selected and a more detailed design phase is entered, tracking and managing the progress of the detailed system design. Such an infrastructure could also be useful throughout the life cycle of a military platform for analyzing potential field problems, evaluating technology enhancements/retrofits, and/or personnel training. The proof-of-concept and viability of such a capability were established in Phase I. The Phase II research will be focused upon the next steps in the development of this virtual prototyping vehicle electrical system management design...
Read MoreIntegrated Simulation/Design/Analysis Infrastructure for SiC-based High-Temperature Power Conversion
Type of Awards: SBIR Phase I with IEDC and Phase II Contract Numbers: FA8650-05-M-2599 and FA8650-06-C-2663 Agency: U.S. Air Force Research Laboratory Status: Completed Periods: 4/1/05 to 1/1/06 and 5/5/06 to 9/5/08 Principal Investigator: C. E. Lucas Abstract: In order to realize the full potential of Silicon Carbide and to facilitate its deployment in high-temperature power electronics applications, it is important to establish an integrated modeling, simulation, and analysis (MS&A) infrastructure to address the special considerations and numerous technical challenges that must be overcome and to support design at the device, subsystem, and system levels. The viability of such an infrastructure has been established in the on-going Phase I research. The overall objective of the proposed Phase II research is to further its development. In particular, the proposed Phase II effort entails: (1) the continued development of a distributed multi-level (device/subsystem/system) integrated (electrical/thermal) MS&A infrastructure to support SiC device development and their application to Air Force systems, (2) the investigation of how SiC device performance is affected by thermal and material properties and how defects influence thermal-electrical coupling, (3) the partitioning of the geometric physics-based device models for implementation in a distributed computer network, and (4) the investigation of the applicability of this powerful MS&A infrastructure to other areas of interest such as computational fluid dynamics, plasma physics, and...
Read MoreModeling of Switched Networks in Continuous State-Space
J. Jatskevich, O. Wasynczuk, E. A. Walters, C. E. Lucas, PC Krause and Associates, Inc. Proceedings IEEE Canadian Conference on Electrical and Computer Engineering, vol. 1, May xxxxx, 2000, pp. 559-563.
Read MoreContinuous State-Space Modeling of Switched Electric Networks
J. Jatskevich, O. Wasynczuk, E. A. Walters, C. E. Lucas, PC Krause and Associates, Inc. An Automated State Model Generator (ASMG) is a tool for modeling and analysis of lumped-parameter power-electronic-based systems. In this modeling approach, the minimal state-space representation of the overall system is generated automatically and updated dynamically based upon the topological state of the system. However, due to the changing topology, simulation of a switched circuit using the ASMG requires the concatenation of solutions to the initial value problems (IVPs) corresponding to the time intervals between commutations. In this paper, a transformation of state variables is derived such that the states are continuous throughout the simulation process. This feature eliminates the need to re-initialize the ODE solver. The continuous state algorithm is verified on a high-pulse-count power supply and sets the stage for state-space averaging and system-level analysis of switched circuits. Proceedings IEEE International Conference on Control Applications, vol. 1, September 2000, pp....
Read MoreAnalysis of Operational Modes of Switched Electrical Networks
J. Jatskevich, O. Wasynczuk, S. D. Pekarek, Purdue University; C. E. Lucas, E. A. Walters, PC Krause and Associates, Inc. In the analysis of power-electronic-based energy conversion systems, it is important to identify the operational modes of the associated converters and inverters. However, as the number of switching elements increases, it becomes more difficult to analytically establish all possible modes of operation. In this paper, a modeling technique is described wherein a state-space representation of the overall system is generated automatically and updated dynamically as each new topology is encountered. Utilizing this approach, it becomes possible to identify the operational modes of converters and inverters based upon the cyclically repeated sequences of topologies that can be observed during steady-state operation. To demonstrate this technique, an example system comprised of a 6-phase synchronous machine, rectifier, and interphase transformer is considered. This system exhibits several distinct modes of operation that depend upon specific circuit connections. These operating modes are automatically identified using the proposed methodology and the results are compared with measured dynamic performance. SAE Transactions Journal of Aerospace, sec. 1, set 3, Month, 2000, pp....
Read MoreDistributed Simulation of Electric Power Systems
J. Jatskevich, O. Wasynczuk, N. Mohd Noor, Purdue University; E. A. Walters, PC Krause and Associates, Inc; C. E. Lucas, Purdue University; P. T. Lamm, U.S. Air Force Research Laboratory Recent advancements in computer networking have enabled the interconnection of inexpensive desktop computers to form powerful computational clusters that can be effectively utilized when simulating electric power systems. In order to maximize the computational gain, it is necessary to identify the computational tasks that can be performed concurrently and to optimally distribute those tasks among the available processors. In this paper, the electrical power system is viewed as a collection of interconnected dynamical subsystems each described by a set of differential/algebraic equations. The tasks that can be performed concurrently are identified and a new approach of optimally distributing the corresponding calculations is set forth. The effectiveness of the proposed approach is demonstrated by distributing a detailed simulation of the Western System Coordinating Council (WSCC) three machine nine-bus system on an SCI-based network composed of three personal computers. The simulation includes the effects of network and stator transients. Using the Runge-Kutta-Fehlberg integration algorithm, a 206% improvement in simulation speed was achieved. Proceedings 14th Power Systems Computation Conference, June 24-28, 2002, Sevilla,...
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