Xiao P.,a Thermadyne Industries Inc. |
Venayagamoorthy G.K.,Missouri University of Science and Technology |
Corzine K.A.,Missouri University of Science and Technology |
Huang J.,SatCon Technology Corporation
IEEE Transactions on Power Electronics | Year: 2010
When designing and building power systems that contain power electronic switching sources and loads, system integrators must consider the frequency-dependent impedance characteristics at an interface to ensure system stability. Stability criteria have been developed in terms of source and load impedance, and it is often necessary to measure system impedance through experiments. Traditional injection-based impedance measurement techniques require multiple online testing that lead to many disadvantages, including prolonged test time, operating point variations, and impedance values at limited frequency points. The impedance identification method proposed in this paper greatly reduces online testing time by modeling the system with recurrent neural networks with adequate accuracy. The recurrent networks are trained with measured signals from the system with only one stimulus injection per frequency decade. The measurement and identification processes are developed, and the effectiveness of this new technique is demonstrated by simulation and laboratory tests. © 2010 IEEE.
Schauder C.,SatCon Technology Corporation
IEEE Power and Energy Society General Meeting | Year: 2011
Photovoltaic (PV) inverters may be subject to different standards and interconnection requirements, depending on their size and interconnection point. PV plants connected at transmission voltage levels may be expected to ride through faults and other disturbances, as expressed in FERC Order 661-A for wind power plants. Islanding detection is not necessary, because customers are not directly served from these plants. On the other hand, PV units connected to distribution feeders are expected to trip automatically during voltage and frequency excursions, as expressed in IEEE Std. 1547. Distribution-connected PV inverters have islanding detection that is designed to meet UL 1741. These conflicting requirements may appear as "wind vs. solar" or "transmission vs. distribution" viewpoints. The impacts on utility-scale PV inverter design and specification are discussed. © 2011 IEEE.
Agency: Department of Energy | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 99.88K | Year: 2009
Current permanent magnet (PM) machinery designs for hybrid and electric vehicles are limited by rotor tip speed and PM material costs. In addition, the Â¿always onÂ¿ PM field results in design voltage compromises and high magnetically-induced losses during partial power operation. In this project, induction machine alternatives for vehicle power train applications will be designed to compete with the PM machinery solutions. In Phase I, concept designs will be developed, and prototype induction machine rotors will be fabricated using cast copper rotor techniques. The rotors will be tested to verify the design models and inform improved designs. In Phase II a complete induction drive system with 30kW steady-state capability and 55kW transient capability will be fabricated and tested with a mating drive and controller. Commercial Applications and other Benefits as described by the awardee: The use of induction machines would benefit hybrid and electric vehicles by requiring fewer compromises for high speed operation and reducing losses associated with partial power use. Furthermore, by avoiding the need to use PM materials, the sensitivity to limited foreign supply and cost volatility would be reduced
Agency: Department of Energy | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 99.29K | Year: 2009
Current Permanent Magnet (PM) machinery designs, used in hybrid electric vehicles (HEVs) and plug-in hybrids (PHEVs), suffer from increased eddy current losses in newer applications with higher operating speeds and/or higher pole count. The resistivity of the flux-carrying materials and the design of the machine impact the character of the losses (magnitude and localization). At partial power conditions, where core losses are high but net power output is low, the net impact on efficiency can be more pronounced. This project will employ commercially available finite element analysis (FEA) models to predict eddy current rotor losses for both interior PM and surface PM machine models. The models will be substantiated and improved upon through experimental testing of PM prototype machines. Commercial Applications and other Benefits as described by the awardee: In addition to advanced vehicle applications, the technology should find use in industrial applications related to compressors, conveyors, machine tools. Likewise, the results should be advantageous for aerospace and military applications, particularly all-electric ship and all-electric aircraft programs
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 69.28K | Year: 2006
SatCon proposes to develop semiconductor packaging technology for the -65/+300°C temperature range. The goal is reliable operation while permitting high device temperature and wide temperature cycles, a particular challenge for existing Power and RF packaging techniques which are suited to the -40/+150°C range. While there are many issues to study further in the Phase I portion of the program, we will build on experience we already have with Wide Band Gap devices and in hi-rel and high-temperature packaging. Our approach is based on: · Minimization of number/types of materials · Use of materials stable at high temperatures · Near-perfect matching of thermal expansions, including :metal conductor layers · Use of multiple parallel die to minimize interface stresses, relative to single large die · Complete elimination of bond wires through use of bump-bonding (flip-chip), compression packaging and other advanced techniques. SatCon has active SiC packaging and applications programs and strong working relationships with the major suppliers (Northrop, Cree & SemiSouth have all endorsed this proposal). We have the facilities, knowledge and personnel to undertake this program through the completion of Phase II and relationships in the Wide Band Gap, Defense and Hi-Rel Industries that will enable us to commercialize the results.