E. Walters, PC Krause and Associates, Inc; S. Pekarek, O. Wasynczuk, Purdue University; A. Koenig, J. Wells, B. P. Loop, PC Krause and Associates, Inc; P. Lamm, U. S. Air Force Research Laboratory Historically, the design of aircraft electrical systems has been divided into separate mechanical (turbine engine) and electrical subsystems, wherein the coupled dynamics have been ignored until hardware integration. However, future loads such as Directed Energy Weapons (DEW), a coupled multi-physics design and analysis capability is required to evaluate system feasibility and establish optimal components in the context of a system-level architecture. In this paper, modeling and simulation techniques that provide a backbone for such design and analysis is set forth. Simulation techniques include a distributed heterogeneous simulation toolbox for interconnecting dynamic component models created using different simulation packages and/or operating systems. Modeling tools include a partitioned finite element technique and a field reconstruction technique that dramatically reduces the computational effort required to perform fields-based simulation of electric machines. Herein, the multi-physics tools are demonstrated for a multi-MW DEW system. The impact of the DEW load on the electrical, mechanical, and energy storage are evaluated under both transient and steady-state conditions and an attempt is made to search for architectures/ designs that minimize weight subject to maintaining stable system performance. 9th Annual Directed Energy Symposium, October 30-November 2, 2006, Albuquerque, NM. Contact Information:...
Read MoreGCU for Megawatt Class Directed Energy Weapons Pulse Generators
Lev Sorkin, Innovative Power Solutions, LLC; E. A. Walters, PC Krause and Associates, Inc. Directed Energy weapon (DEW) systems are being developed for both ground and airborne applications. Typically, they consist of microwave or laser powered guns. Both the microwave application and the diode based laser applications require significant amount of power. This power ranges from several hundred kilowatts (kW) for microwave applications to Megawatts (MW) for laser applications. The laser application requires that the full power be available for short duration, typically 5 seconds, which could be repeated several times with short pauses in between. The control of a generator, which delivers Megawatt of the intermittent power greatly differs from the of normal steady state generator control. It poses significant challenges. Application of power (and for this matter its removal) is a transient phenomenon that takes time and its effects ripple through the whole system. In the case at hand, the large applied power, which is required for a short duration, can have a more significant effect on the system. Furthermore, it is imperative that the full power will be available for the required duration with no degradation in quality on both ends (application and removal). There are four entities that interact affecting the performance of the...
Read MoreAutomated Evolutionary Design of a Hybrid-Electric Vehicle Power System Using Distributed Heterogeneous Optimization
Dionysios C. Aliprantis, O. Wasynczuk, Purdue University; N. Wu and C. E. Lucas, PC Krause and Associates, Inc; M. Abul Masrur, U.S. Army RDECOM-TARDEC The optimal design of hybrid-electric vehicle power systems poses a challenge to the system analyst, who is presented with a host of parameters to fine-tune, along with stringent performance criteria and multiple design objectives to meet. Herein, a methodology is presented to transform such a design task into a constrained multi-objective optimization problem, which is solved using a distributed evolutionary algorithm. A power system model representative of a series hybrid-electric vehicle is considered as a paradigm to support the illustration of the proposed methodology, with particular emphasis on the power system’s time-domain performance. 2006 SAE Power Systems Conference, November 7–9, 2006, New Orleans, LA. Paper #...
Read MoreDistributed Heterogeneous Simulation of a Hybrid-Electric Vehicle Drive System Using the Simplorer Software Product
N. Wu, C. E. Lucas, Curtis Rands, I. E. Simpson, PC Krause and Associates, Inc; Dionysios C. Aliprantis, Purdue University; M. Abul Masrur; U.S. Army RDECOM-TARDEC To support research and analysis requirements in the development of future hybrid-electric drive systems, a flexible and efficient means of predicting the dynamic performance of large-scale multi-disciplinary systems prior to hardware trials is crucial. With the development of Distributed Heterogeneous Simulation (DHS), the technology now exists to enable this type of investigation. Previously, DHS was shown to allow the interconnection of component simulations running on a single computer or networked computers and developed using any combination of a variety of commercial-off-the-shelf software packages. The US Army is interested in using the Simplorer software product from Ansoft Corporation to model various subsystems that are incorporated with such vehicle system simulations. In this paper, the DHS technique is expanded to support the Simplorer software package; thus, allowing subsystem models developed using this tool to be interconnected to form a dynamic system simulation. A representative hybrid-electric vehicle has been selected as a study system and includes propulsion, generation, weapon, and payload subsystems. Models of the components/subsystems that comprise the power system have each been developed in MATLAB/Simulink or Simplorer. Utilizing the system simulation, studies have been performed to illustrate the dynamic interactions between the subsystems when simulated on a computer network containing Windows based personal computers. 2006 SAE Power Systems Conference, November 7–9, 2006, New Orleans, LA. Paper #...
Read MoreIntegrated Hardware-in-the-Loop Simulation of a Complex Turbine Engine and Power System
Suraj Ramalingam, Aaron Green, Peter Lamm, U.S. Air Force Research Laboratory; Hank Barnard, Scientific Monitoring, Inc; E. A. Walters, J. R. Wells, PC Krause and Associates, Inc. The interdependency between propulsion, power, and thermal subsystems on military aircraft such as the F-35 Joint Strike Fighter (JSF) and F-22 Raptor continues to increase as advanced war-fighting capabilities including solid-state radars, electronic attack, electric actuation, and Directed Energy Weaponry (DEW) expand to meet Air Force needs. Novel analysis and testing methodologies are required to predict these interdependencies and address adverse interactions prior to costly hardware prototyping. As a result, the Air Force Research Laboratory (AFRL) has established a dynamic hardware-in-the-loop (HIL) test-bed wherein transient simulations can be integrated through advanced real-time simulation with prototype hardware for integrated system studies and analysis. This paper details a test-bed configuration where a dynamic simulation of an aircraft turbine engine is utilized to control a dual-head electric drive stand. The drive stand is connected to an electric generator and associated power system implemented in hardware. The electromagnetic torque produced by the generator is measured and fed back into the turbine engine simulation as a load to the shaft. The HIL capability of this test-bed configuration enables reduced cost altitude testing, supports the design and analysis of integrated starter / generators and alternative power / propulsion architectures, and sets the stage for advanced integrated turbine engine / generator control design. 2006 SAE Power Systems Conference, November 7–9, 2006, New Orleans, LA. Paper...
Read MoreCoupled-Circuit Modeling of 3, 6, and 9-Phase Induction Machine Drive Systems
Juri Jatskevich, University of British Columbia, Canada; E. A. Walters, C. E. Lucas, PC Krause and Associates, Inc. This paper describes a coupled-circuit physical-variable modeling of multiphase induction motors. The presented modeling interface makes it straightforward to implement an induction machine with arbitrary number of phases and/or phase groups on the stator and the rotor. The 3-, 6-, and 9-phase motors are simulated and compared. It is shown that machines with higher number of phases have less severe torque pulsation and the stator current increase following a loss of one phase. For the 9-phase machine, several studies involving loss of multiple phases are also presented, wherein the relative location of the faulted phases is shown to have a significant impact on redistribution of currents and resulting electromagnetic torque. The proposed models can be used to represent induction motors and generators for transient studies involving multiple faults, system-level reconfiguration, and survivability. 2006 SAE Power Systems Conference, November 7–9, 2006, New Orleans, LA. Paper...
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