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Expert has spent a large part of his career developing products in technical leadership positions in the general category of power electronics. He is a member of the IEEE Power Electronics Specialists Society and has attended and presented papers and seminars at the IEEE Power Electronics Specialists Conference, the Applied Power Electronics Conference, and High-Frequency Power Conversion Conferences. Expert has developed and published a mathematical model and associated spreadsheet for topology selection and resource allocation for optimal converter design for a given set of operating conditions and is an expert in design tradeoffs. He holds thirty-two patents and has several more patents pending. His inventions include several new converter families with zero voltage switching and universally applicable zero voltage switching cells that can be used to transform hard switching converters into soft switching equivalents. Several power conversion companies are using Expert's inventions on their leading-edge products. He has developed synthesis techniques that transform known circuits with pulsating terminal currents and poor EMC into new circuits with improved terminal ripple current properties and common mode noise cancellation. He has invented other circuit forms that improve efficiency and simplicity. Expert has invented a new planar magnetic structure that improves both efficiency and power density. More recently he has been involved in the design and development of grid-connected inverters for solar cell arrays, circuit design for wide bandgap semiconductor devices, drivers for solid-state lighting applications and drivers for silicon carbide field effect transistors. He has also served as the electronic system architect for the development of a Power Supply In Package (PSIP) product that exceeds the power density and efficiency of prior art products by a wide margin.

Expert has designed single and multi-output AC to DC converters of the forward, boost, and flyback types for various applications. He has designed 115 VAC input types and compliant input types that can operate over both 115 VAC and 230 VAC range for domestic and European mains applications. He has also designed power factor correction systems and holds a patent on a power factor correction system that accomplishes both tightly regulated line current and tightly regulated DC output voltages with significant efficiency, size, weight, and cost improvements over the prior art.

Expert has designed many single and multi-output DC to DC converters including both isolated and non-isolated types for a wide variety of applications. He holds patents and has patents pending on many new DC to DC converter topologies that improve efficiency, packaging density, and EMC over the existing art. One example of a new invention is a buck converter that accomplishes zero current ripples at both input and output terminals. This buck converter requires only two power MOSFETs, one magnetic circuit element (which can be a toroid or an Ecore) a control circuit, and a few capacitors. He has also invented several zero voltage switching techniques that can transform hard switching converters into more efficient soft switching equivalents capable of operating efficiently at the higher switching frequency and higher power density.

Expert has designed both switched-mode and linear power supply circuits as well as special purpose power supply circuits for applications such as forced current sharing parallel redundant systems, inrush current and inrush current slope limiting, multi-output sequencing, hold up circuits, and input and output filters for interface and noise control. Expert has designed low-cost commercial power supplies and high frequency, high density, high-performance circuits for military and space applications.

Expert has performed design, analysis, and modeling of switched-mode power supplies. His work includes a full spectrum of applications, power levels, and topologies. He has been active in all phases of development from conceptualization to manufacturing. Expert is responsible for some of the leading commercial advances in the field of switched-mode power supplies.

Expert has designed, analyzed, and modeled voltage regulator circuits. He has considerable education and experience in control loop stability analysis for amplifiers and voltage regulators. He has contributed an innovative method for improving load regulation under varying load conditions using the concept of negative output impedance about which a paper was published. He has performed trade-off studies, modeling, and analysis comparing line regulation in current mode and voltage feed-forward mode converters.

Expert has designed a wide range of amplifier types including audio power amplifiers, video amplifiers for CRT displays, video deflection amplifiers, audio pre-amplifiers, and control amplifiers for servo systems. He is also highly accomplished at low noise design for sensor interface.

Expert has designed several types of filter circuits including electromagnetic interference (EMI) suppression filters and has performed EMI filter analysis for high-frequency switched-mode power supplies for both differential and common mode noise rejection.

Expert has designed a wide variety of analog circuits for a wide variety of applications including audio, instrumentation, industrial automation control, servo control, communications, and power control.

Expert has designed a variety of switching and timing circuits for security alarm systems, instrument systems, automation systems, and power supply sequencing.

Expert has provided much of the conceptual design and some of the implementation of a 32-bit Windows-based power converter simulation tool which accomplishes precise time and frequency domain simulation of complex power converter systems.

Expert has used electronic modeling extensively as a design and analysis tool for a variety of circuit types. He has used PSPICE extensively to perform both average and real-time modeling of power converter circuits and systems. He has also worked extensively with Analog Workbench and with Excel as a digital signal processing machine. He has written a computer program for the synthesis of active filters. He has developed spreadsheets for magnetic circuit design aids.

Expert has designed both linear and switched-mode audio power amplifiers for a number of different applications. He recently designed a zero voltage switching amplifier with 1 megahertz ripple frequency for an audio noise cancellation application.

Expert designed a high power 60-hertz input, 3 phase 400 hertz output uninterruptible power supply combining a power factor corrected AC to DC converter and battery charger and three DC to AC converters.

Expert has been involved in the development of a very high-efficiency grid-connected inverter for a solar cell array application. He has designed a high power DC to AC converter as part of an uninterruptible power supply system.

Expert has designed high power UPS with AC output. He has also designed DC output supplies with substantial hold up capability and charging systems.

Expert has designed control systems for factory automation, instrumentation, engine control, and quality control. He has used board-level computers with microprocessor development systems, embedded microcontrollers, desktop computers, and programmable controllers. He has worked with a wide variety of motors and actuators, sensors, switches, and display devices, and has developed circuits for interfacing, multiplexing, decoding, and driving these devices under computer control.

Expert has done control loop dynamic stability analysis for many types of closed loop systems including engines, power converters, motor systems, valve systems, electro-surgical generators, and high and low-frequency amplifiers. He has also been active in modeling new types of control systems with performance improvements over the conventional PID-type controllers. He has experience using network analyzers for generating Bode plots for control loop stability analysis.

Expert has authored several papers which describe converters with resonant transition designs. He developed and holds a patent on a low parts count converter topology which accomplishes zero voltage resonant transition switching and low-recirculating energy. He has also developed high-power resonant transition phase shift modulated converters and resonant transition switching audio power amplifiers.

Expert has been involved in the development of power factor correction schemes for a variety of applications. As part of an uninterruptible power system, Expert designed a boost pre-regulator power converter that achieved near unity power factor. He holds patents and has others pending on power factor correction schemes.

Expert has taken a special interest in electromagnetic interference for power converters. He has designed power converters with exceptional performance in regards to electromagnetic interference for noise sensitive space applications. He holds four patents on circuits and techniques for improving electromagnetic compatibility of power conversion circuits. He has also taught a professional advancement course on EMC enhanced power supply design and will be teaching expanded courses on EMC for power supplies in the future.

Expert has designed very successfully electromagnetic interference filters for power supplies and has taken a special interest in this subject area. He has taught electromagnetic interference filter design as a part of a professional advancement course on EMC enhanced power supply design.

Expert has designed many electronic circuits for power conversion. He has invented many new circuits and new circuit synthesis techniques for power conversion circuits. Most of his 15 granted patents and three patents pending reveal new electronic circuit designs for power conversion.

Provided Galil Medical with an approach for improving power factor correction and increasing deliverable power to a motor for the compressor for a cryogenic cooler. Provided Microsemi with a system circuit design for the first commercially available driver IC for Silicon Carbide vertical JFETs and bipolar transistors and helped with the debugging process that leads to its successful release. Provided ASIC Advantage/Microsemi with a working model and an electronic system design for high efficiency, high-density Power Supply In Package product. Provided system and circuit design and debugging help for several isolated and non-isolated high efficiency and high-density product designs to Elektra. Provided a power conversion design review for Belmont Industries that pointed out design flaws that would have resulted in greater cost, size, and weight.