Marchant C.C.,National Geospatial-Intelligence Agency (NGA) |
Wojcik M.D.,Energy Dynamics Laboratory |
Bradford W.J.,Energy Dynamics Laboratory
IEEE Transactions on Geoscience and Remote Sensing | Year: 2012
A new lidar algorithm is presented as part of a technique for estimating aerosol concentration and particle-size distribution (PSD). This technique uses a form of the extended Kalman filter (EKF), wherein the target aerosol is represented as a linear combination of basis-aerosols, so that the estimated PSD of the aerosol is a linear combination of the PSD of the individual basis-aerosols. The state vector of the filter contains the amplitudes of the basis-aerosols, eliminating the need for an intermediate step of estimating scattering coefficients. Point-sensor instruments and Mie scattering theory are used to establish the relationship between basis-aerosols and measured power. The algorithm is demonstrated using both synthetic test data and field measurements of biological and nonbiological aerosols. The estimated PSD allows straightforward calculation of parameters such as volume-fraction concentration and effective radius. © 2006 IEEE.
Wojcik M.D.,Energy Dynamics Laboratory
Optics InfoBase Conference Papers | Year: 2011
Aglite, a 3-wavelength elastic lidar system is used to measure the particulate emissions from a process water treatment facility related to fracture mining petroleum extraction. Particulate emissions were found to be low for the two kinds of water treatment studied. © 2011 OSA.
Simmons J.A.,Energy Dynamics Laboratory |
Marchant A.B.,Energy Dynamics Laboratory
Journal of Laser Applications | Year: 2012
A class 4 pulsed laser can be operated in a safe regime without reducing instantaneous irradiance or pulse energy by shortening its dwell time through duty cycle reduction or scanning. A conservative relationship for hazard distance as a function of scan rate is derived for the case of a scanning, retina safe laser. © 2012 Laser Institute of America.
Sharp B.,Energy Dynamics Laboratory |
Wu H.,Energy Dynamics Laboratory
Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC | Year: 2012
This paper presents the first conceptual description of a fixed frequency soft switched LCL load-resonant converter for Inductive Power Transfer (IPT) systems. By using Asymmetric Voltage Cancellation (AVC) control to avoid diode reverse recovery loss (DRRL), ZVS operation over a wide load range becomes possible. The circuit was solved using a time domain analysis method and the optimal control trajectory was determined using a greedy salesperson algorithm. Experiments on a 60W prototype were carried out to validate the regions for which DRRL is avoided and were used to compare the improved performance against previous fixed frequency control strategies. It has been shown that the efficiency can be improved up to 5% and the THD can be reduced up to a factor of 7 compared to phase shift and Asymmetric Duty Cycle control, respectively. © 2012 IEEE.
Wu H.H.,Energy Dynamics Laboratory |
Gilchrist A.,Energy Dynamics Laboratory |
Sealy K.,Energy Dynamics Laboratory |
Bronson D.,Energy Dynamics Laboratory
2012 IEEE Energy Conversion Congress and Exposition, ECCE 2012 | Year: 2012
This paper presents the design of a 5kW inductive charging system for electric vehicles (EVs). Over 90% efficiency is maintained from grid to battery across a wide range of coupling conditions at full load. Experimental measurements show that the magnetic field strength meets the stringent International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for human safety. In addition, a new dual side control scheme is proposed to optimize system level efficiency. Experimental validation showed that a 7% efficiency increase and 25% loss reduction under light load conditions is achievable. The authors believe this paper is the first to show such high measured efficiencies for a level 2 inductive charging system. Performance of this order would indicate that inductive charging systems are reasonably energy efficient when compared to the efficiency of plug-in charging systems. © 2012 IEEE.