Engineer Power
Resume:
Carl Klaes
Livonia, MI *****
abocyz@r.postjobfree.com
EXPERIENCE
Mahindra-Amphere, Power Electronics Principal Engineer, December 2012 to Present
• Responsible for development of a 48V, 2.2KW scooter electronics system including the PMDC motor controller, DC/DC converter and battery charger.
Meritor, Power Electronics Principal Engineer, September 2006 to October 2012.
• Lead an electronics team for a hybrid electric Class 8 truck’s inverter hardware and software development. Part of Supertruck, a US Dept of Energy industry cost share program. Navistar is developing a class 8 truck that will run battery only or series electric to 40MPH and engine only or parallel assist mode over 40MPH. Meritor is providing the electric machines and inverters for this “dual mode” operation. This system is also part of a “Cooperative Research and
Development Agreement” with Oak Ridge National Labs. The dual mode drive consists of two switched reluctance machines, each 360KW with 1100Apk phase currents fed from a 700Vnom DC bus.
• Developed PSPICE model of the SR machines that includes saturation and back emf. Provides for evaluating capacitor bank ripple currents and IGBT power losses at an operating point. The inverter was successfully designed from these simulations and test results verified the model.
• Designed all hardware:
* Isolated gate drive circuits
* Designed dc converters and planar pcb isolation transformers
* Guided safety critical layout for creepage, clearance and noise rejection.
* Selected Infineon IGBT modules based on PSPICE simulations.
* Custom film capacitors were developed with ECI from PSPICE simulations of ripple currents.
* Cold Plates were designed by Wolverine Tube / Micro Cool to PSPICE simulation predictions of IGBT power losses.
* Wrote SR motor control code for TI ‘F2808 DSP with Code Composer Studio in ‘C’. Phase current is controlled to a hysterisis band using time based ADC sampling. Output drive signal advance utilizes the compare circuits to provide 0.1degree accuracy to 12kRPM. Speed and position are estimated from the input capture of three hall effect sensors. This is an innovative approach that eliminates the FPGA used in most SR controllers. Demonstrated four quadrant control on a dynamometer. Implemented J1939 CAN bus and re-FLASH over CAN.
Visteon, Technical Fellow in Power Electronics, January 2002 to September 2006.
• Designed 3kw Starter/Alternator Inverter. Created a custom 16mil cu/ 5mil FR4 / 16mil cu circuit board that utilized SMD
MOSFETs to switch 600Amps. This innovation replaced a bus bar / epoxy / thru hole MOSFET design that was too
complex and expensive to manufacture. This was called SpeedStart and the technology was purchased by CPT. There
is a picture on http://www.cpowert.com/products/speedstart.htm in the cutaway view.
• Designed 5kw induction motor inverter mounted in end bell for a vehicle thrust assist application. Developed a PSPICE
model for a space vector modulator and implemented ‘DQ’ induction motor models.
• Designed a power electronics drive system for a vehicle equipped with a 30kW doubly fed induction generator feeding a
20kW induction motor. Created PSPICE system models that accurately predict system response as well as all electronic
component stresses.
Visteon, Chassis Advanced Technology, Product Design Engineer, January 2000 to March 2002.
• Designed a quad 1000 Amp, 48V eddy current brake controller with a custom heavy copper circuit board. This circuit
rectified a generator output with SMD diodes in metal packages cooled on both sides and SMD MOSFETs.
• Developed a unique method of utilizing ultra-capacitors for a hybrid vehicle. By using the inverter in a switch mode
rectifier mode during charging, an expensive DC-to-DC converter is not needed to charge the ultra-cap. Two conference
publications were presented on this subject.
Prestolite Electric, Technology Center Manager, March 1998 to January 2000.
• Responsible for small corporate research facility. Key activities included: Establishing research projects; Recruiting key
personnel; Establishing goals and budgets. Actively involved in motor power electronics and controls design.
Prestolite Electric, Senior Electronics Engineer, August 1994 to March 1998.
• Responsible for complete design of electromagnetic machine controls, including simulation, software, interface and
sensor circuits, power electronics and packaging. Acted as consultant to divisional engineers on all types of electronic
developments. Acted as EMI consultant to facilitate compliance to standards.
• Designed a complete motor controller for a 2.5HP, 3-phase, 6/4, switched reluctance motor, targeted for small electric
vehicles. Modeled motor and power electronics in PSPICE. Designed phase-locked loop position sensor that produces
better than degree resolution from simple opto-interupter. Software written in "C" for V25 microprocessor.
• Redesigned the HUMMER glowplug control box (Prestolite part no. WSU-4009) to pass MIL-STD_461D radiated
emissions test. Modeled circuits in PSPICE and constructed LISN for pre-qualification testing.
• Tested alternators for conducted and radiated emissions to CE standards at Irelands National Electronics Test Center
(NETC)
Cklaes
Pg 1 of 3
EXPERIENCE (cont’d)
• Designed an alternator fault-detection circuit that senses all alternator failure modes in a simple, cost-effective analog
circuit. Marketed as the "Smart-Check" regulator. Developed a dynamic dq alternator model in PSPICE and ran system
simulations of failure modes to correctly predict fault sensor operation.
Software Services, Contract Engineer, May 1994 to August 1994
• Designed hardware and software for Ford automatic climate controls.
MagneTek, Project Engineer, May 1988 to May 1994
• Responsible for all phases of industrial controls development: digital design, analog design, software design and safety
and EMI standards compliance.
• Designed "Quick-Set IV" programmable logic switch (patent no. 5,227,965). Provides set-point control in high-speed
machine applications.
• Designed several microprocessor based real-time industrial controllers. Experience with the Motorola 68332 series and
several 8-bit processors. Designed multiple FPGA boards.
• Experienced with "C" and Assembler programming.
• Designed off-line power supply to FCC specifications for conducted and radiated emissions. Radiated emissions testing
done at Eaton test facility. Personally tested conducted emissions with a LISN and spectrum analyzer. Tested several
digital designs for field susceptibility with sweep generators and a TEM cell. Re-designed board layouts for field rejection.
DESIGN TOOLS EXPERIENCE
• Matlab / Simulink. Developed a simple look up table based full vehicle model for hybrid / electric vehicle performance
comparisons.
• Code Composer Studio. Developed SR motor control in ‘C’ for the ‘F2812 DSP.
• PSPICE Modeling. Developed a PSPICE model for a Space Vector Modulator and implemented DQ permanent magnet
motor and induction motor models. Have simulated a full field oriented controlled inverter / motor system. These models allow
quick and very accurate sizing of all inverter components, including DC link capacitor ripple currents and transistor power
dissipation. Developed an SR motor model that includes saturation and speed based emfs that has been verified by test.
• SAUNA Modeling. Have modeled from transistor die, thru transistor packaging, thermal interface materials and water
cooled cold plates or air cooled heat sinks.
• FEMM Magnetics FEA. Have modeled high frequency transformers and inductors.
• ORCAD and Protel. Circuit board schematic capture and board layout experience.
PATENTS / PATENT APPLICATIONS
• US Patent Application US 2012/0176084 A1: Method and apparatus for generating a charging
circuit. This invention utilizes the power electronics of a switched reluctance motor controller and the phase windings of a
switched reluctance motor to make up a singe stage boost converter capable of charging a battery with power factor correction
(PFC) in the AC line. This provides the capability to charge the Supertruck from a 220Vac line without any additional charging
equipment
• US Patent 7081725: Power electronics apparatuses for double-fed induction generator to induction
motor drive system. The idea here was to use slippage from a front wheel to spin a generator and feed the power to the
rear wheels. Using a doubly fed induction generator reduces the power rating of the inverter needed. The output of the
generator directly feeds a three phase motor on the rear differential. Referenced by 5 newer patents.
• US Patent 7029077: Method and apparatus for power management of a regenerative braking
system. A vehicle braking system which includes electromagnetic and friction braking. The electromagnetic braking system
includes a generator which supplies power to eddy current brakes. In the event the generator produces an amount of power
greater than that needed by the electromagnetic braking system, the generator supplies power to a battery. Referenced by 8
newer patents.
Cklaes
Pg 2 of 3
PATENTS / PATENT APPLICATIONS (cont’d)
• US Patent 6,871,919: Method and apparatus for power management of a braking system. Same
system as above (7029077). In the event the generator is unable to supply a predetermined amount of power to the eddy
current brakes, friction braking is activated. Referenced by 3 newer patents.
• US Patent 6,753,619: Flywheel based regenerative energy management system. This invention
describes a regenerative energy management system having a flywheel assembly with an integrated motor-generator which is
coupled to a drivetrain motor-generator. The system controller has integrated inverters and voltage control that determine the
direction and flow of current between the flywheel assembly and the driveline motor-generator. Referenced by 15 newer
patents.
• US Patent 5,227,965: Fast Programmable Limit Switch . A programmable limit switch is a multicircuit on/of
position based controller. This patent employs high speed special purpose hardware circuits and a general purpose
microcontroller to achieve high speed operation. A state sequencer controls the high speed special purpose hardware. Using
fast logic the update time is greatly reduced over a software only implementation. Referenced by four newer patents.
• US Patent Application: Application # 60/013,603 – A Method and Apparatus for Detecting a
Multitude of Faults in an Automobile Charging System. This novel circuit is capable of detecting any alternator
fault under all operating conditions. Most faults are simple to detect by simply monitoring the output voltage. However, an
open phase is normally undetectable except at full load conditions. The circuit uses simple analog signal conditioning to
compare the relative magnitude of averaged phase voltages.
PUBLICATIONS
• Method of Selecting Bus Capacitance and Estimating the Voltage Ripple and RMS Ripple Current of
a Battery Fed PWM Circuit. Presented at the PCIM 2001 Power Electronics Conference. This paper
presents a new method of evaluating DC bus capacitor rms ripple current and ripple voltage for PWM and motor control
circuits. Simple equations are shown to be good approximations for many applications. Factors limiting these approximations
are evaluated.
• Modeling Optimum Charging of an Ultra-Capacitor by an Alternator. Presented at ELECTRIMACS
2002, Montreal. Operation of an ultra-capacitor in a vehicle regeneration cycle is explained. The maximum power curve
of the alternator is explained. An algorithm is derived to set the duty cycle of a DC-to-DC converter so that the alternator
operates on this maximum power curve while charging the ultra-capacitor.
• Maximum Charging of an Ultra-Capacitor Using Switch Mode Rectifiers in a Regeneration Cycle .
Presented at IEEE Vehicle Power and Propulsion (VPP ’05). This paper expands on the work presented at
Electrimacs ‘02 to implement the charging controller in a switch mode rectifier rather than a DC-to-DC converter – a major cost
savings. This publication referenced by Basu et.al., “A novel design scheme for improving ultra-capacitor lifetime while
charging with switch mode converters” PESC08.
EDUCATION
MSEE, University of Michigan – Dearborn, Dearborn, MI 1993.
BSEE, Lawrence Technological University, Southfield, MI, 1988.
Professional Development Courses:
• Dynamics and Control of AC Drives: 1 week training at University of Wisconsin
• TI ‘F28335 3 day Seminar
• TI Digital Power 1 day Semiar
• Matlab Simulink: 1 week training at U of M – Dearborn.
• Switched Reluctance Motor Control: SAE (Society of Automotive Engineers) 3 day seminar.
• Electronics Packaging / Thermal Analysis: SAE 3 day seminar
• Reliability Prediction of Automotive Electronic Components: SAE 3 day seminar
• Switch Mode Power Supply Design: 1 week course by Abe Pressman
• Motor Design Seminar (1 week tutorial): Visteon Internal Training
Cklaes
Pg 3 of 3
Contact this candidate