ORC Expert Advisory Services ORC International

  home    |    find an expert    |    request an expert    |    join our network    |    about us     expert login  
Expert Consulting and Expert Witness Services
  search tips 
Share this page:  Send to LinkedIn Send to Facebook Tweet This Email Print

 Expert  107858

Expert in Electronic Drive/Power Quality

Available for your Consulting and Expert Witness Needs

Colorado (CO)
Education Work History Career AccomplishmentsPublicationsConsulting Services Expert Witness

Summary of Expertise: Listed with other top experts in: 
Expert is concerned with the design, performance, and control of electrical energy conversion devices. He has research, development, and design experience in all types of variable-speed or constant-speed electromechanical drives, including variable-frequency/variable-voltage drives. He designed electric-hybrid, variable-speed drives for automobiles and variable-speed train drives for wind power plants employing insulated-gate bipolar transistors (IGBTs) for rectifier and inverter circuit components. The electric machines involved are mostly of the permanent-magnet type with neodymium-iron-boron (NeFeB) magnets with field weakening, resulting in high efficiencies.

A significant portion of Expert's career in the design of drives has involved the optimization of single- and three-phase induction motor drives with respect to efficiency for given constraints (costs, performance characteristics). Comparison of several constrained optimization techniques involving nonlinear programming approaches lead to similar solutions. It can be expected that such optimal design techniques will be heavily used due to the recent passage of the Energy Policy Act of 1992.

Within the emerging field of power quality in power systems, Expert is an expert in the analysis of the generation, propagation, mitigation, and prevention of harmonics and fractional harmonics in distribution systems. He uses fundamental Newton-Raphson type load flow, harmonic load flow (HARMFLO), and the electromagnetic transients program (EMTP). He studied impacts of voltage and current harmonics on power system components and end-use devices as well as the effects of geomagnetically induced currents in power systems.

In his design and development work, Expert routinely uses nonlinear magnetic field analysis such as finite element and finite difference methods in two and three dimensions. Applications of such methods include induction, synchronous, permanent-magnet, and homopolar machines; linear and rotary motion electromechanical actuators, magnets, and inductors. These numerical methods solve the linear and nonlinear Laplace, Poisson, and the diffusion equations, that is, magnetostatic as well as electrodynamic field problems.

Expert's most recent work concerns improvement of the seasonal energy efficiency ratio (SEER) of heat pumps and the design of variable-speed wind power plants, hybrid electric cars with recovery of braking energy, and of high-efficiency electric motors and drives exploiting permanent magnets. New materials such as compressed powdered iron cores are employed. Energy conservation is possible through motor efficiency improvement, distribution system power factor correction, mechanical system and motor matching with adjustable-speed drives, and process optimization.

Expert has designed pulse-width-modulated inverters and rectifiers and their simulation with SPICE. He has dealt with reverse-recovery currents of diodes and transistors and their suppression. Gating circuits with either transformer or optical coupling has been applied to single- and three-phase systems where the gating pulses are synchronized with an external periodic signal via a voltage-controlled oscillator. Control of inverters is made such that these devices can continuously change the power factor and waveshape of the output current.


direct energy conversion


variable frequency-variable voltage drive


energy conversion


electric-power conversion


energy-efficient drive


energy-efficient electric motor


energy-efficient electrical system


three-phase induction motor


electric power quality


finite element analysis


magnetic field theory


electric automobile


electric drive


electric energy generation


electric motor


electrical machinery


energy conservation


motor drive


renewable energy source


electric actuator


phase inverter

Expert has consulted with numerous businesses concerning application of electric machines, transformers, and actuators. He has resolved issues related to rewinding of electric machines, harmonic currents in the neutrals of transformers, and application of induction motors within bore holes. Electronically commutated DC, stepper, and switched reluctance motors, field-oriented control, and field weakening appear to be of recurring importance. He has advised on design of magnetic couplings and electromagnetic actuators consisting of permanent-magnet and voice coil, as well as torque motors.

Most electric quantities encountered are nonsinusoidal, Expert maintains, so conventional analog metering is not possible. With the emergence of flexible PCs, analog to digital (A/D) and digital to analog (D/A) converters as well as programmable arbitrary waveform generators, the measurement of nonsinusoidal/sinusoidal quantities can be preformed based on 12 to 16 bit sampled data acquisition networks. Expert has gained considerable laboratory experience through recent research and development work at the University of Colorado with respect to on-line monitoring of transformer losses and derating.




current transformer


electric machine


digital data acquisition

Show Secondary and Basic Areas of Expertise
Expert may consult nationally and internationally, and is also local to the following cities: Denver, Colorado;  Colorado Springs, Colorado;  Aurora, Colorado;  Fort Collins, Colorado;  Arvada, Colorado;  Westminster, Colorado;  Boulder, Colorado;  Greeley, Colorado;  Longmont, Colorado;  and Cheyenne, Wyoming.

Often requested
with this expert:

Power Electronics, Motor Drives, Renewable Energy, Etc.
Motor and Generator Design and Development
Electric Motors, Generators, Wind Energy, Voltage...
Electrical Engineering, Power Distribution, Control...

Year   Degree   Subject   Institution  
1970   PhD   Electrical Engineering   University of Colorado - Boulder  
1967   MS   Electrical Engineering   University of Stuttgart, Germany  
1965   BS   Electrical Enginnering   University of Stuttgart, Germany  

Work History:
Years   Employer   Title  

1979 to


(Undisclosed University)


Professor of Electrical Engineering


1971 to 1977



Senior Research and Development Engineer in Industry


Career Accomplishments:
Professional Appointments

Expert is a Fellow of the Institute of Electrical and Electronics Engineers. He is a reviewer of major technical journals in the fields of power systems, energy conversion, industry applications, and power electronics.


He was awarded a paper prize in 1972 by the German Association of Electrical Engineers, the IEEE 1989 Prize Paper Award of the Power Engineering Society, and the IEEE 1989 Power System Relaying Committee Award.

Publications and Patents Summary

He has published and presented about 100 technical papers in his chosen areas of energy conversion and control theory.

Consulting Services:
Recent Client Requests:
  • Expert for consulting on Transience in High Voltage Transformers.
  • Expert in Induction Motors (1-500 HP) for energy conservation standards.
  • Expert for consulting on Arc tracking and arc pressure.
  • Expert in de rating guidelines for consulting on upgrading based on today's technology guidelines based on RACs .
Click the green button above to contact Expert for a free initial screening call regarding your expert consulting needs.  Expert is available for consulting to corporate, legal and government clients.  Remember, your initial screening call to speak with Expert is free.

Expert Witness:
Recent Litigation Client Requests:
  • Electrical engineering and wind turbine expert for consulting on wind turbine crash case.
Click the green button above to contact Expert for a free initial screening call regarding expert testimony, litigation consulting and support, forensic services, or any related expert witness services.  A few litigation needs include product liability, personal injury, economic loss, intellectual property (patent, trademark, trade secret, copyright), and insurance matters.  Remember, your initial screening call to speak with Expert is free.

Language Skills:
Foreign Language  


Need the right expert?  We can help!

home       find an expert       request an expert       join our network       about us

Intota is now ORC Expert Advisory Services