Introduction to Electric Machines and Drives

In the last 30 years, the introduction of power electronic drives with motors has led to new design opportunities. The increased integration of these drives and machines has triggered a quantum leap in productivity, efficiency and system performance.

This practical, hands-on course will give you a solid introduction to this rapidly expanding field under the guidance of industry experts.

This course will benefit those new to the field of electrical rotating machines and drives and those desiring a refresher from the perspective of actual designs from practitioners. People who will find this course valuable include those working in the fields of:

• Appliance drives
• Cranes and elevators
• Precision motion control
• Renewable/alternative energy
• Electric/hybrid-electric vehicles Autonomous vehicle control
• Aerospace, marine, and military vehicles

Introduction

Review: AC Systems and Three-Phase Circuits

• AC voltages and currents
• Effective or RMS values
• Complex numbers and phasor concepts
• Why three-phase?
• Harmonics
• Per-unit system

Review: Electromagnetics and Energy Conversion

• Magnetic fields, flux, and force
• Faraday’s Law of Induction
• Ferromagnetic materials
• Inductors and transformers
• The DC machine

Basics of AC Machines

• Elementary AC machines: air-gap MMF, flux, voltage waveforms
• Distributed stator windings
• Elementary rotor-stator coupling
• Three-phase operation

Induction Motors: Steady State

• Induction machine types: wound rotor, “squirrel cage” rotor
• Circuit models
• Concept of slip
• Torque-speed curves

Synchronous Machines: Steady State

• Synchronous machine types: wound rotor, permanent magnet
• Circuit models and vector diagrams
• Capability curves

Converter Power Electronics: Basic Theory, Devices

• Review of circuit fundamentals
• Basic converters
• Conversion stages
• Device characteristics and capabilities

AC Inverter Basics: VSI, CSI, Modulation

• Basic inverter system
• Voltage source inverter (VSI)
• Current source inverter (CSI)
• Modulation techniques
• Pulse width modulation (PWM)
• Practical considerations

Adjustable Speed Drives: Basics

• Basic adjustable speed drive systems
• Review: DC machine speed control
• Varying voltage
• Varying frequency
• Motor and drive selection

Adjustable Speed Drives: Volts/Hz Control

• Concepts of constant flux and torque
• Operation at constant torque or power
• Low speed operation
• Basic Volts-per-Hertz system
• Drive limitations

Adjustable Torque Drives: Basics

• Ideal adjustable torque systems
• Review: DC machine torque control
• Key elements of torque control
• Synchronous machine torque
• Induction machine torque-slip control

Induction Motor Field Orientation

• Review machine forces: Lorentz and reluctance
• Rotating vectors: stator and rotor currents
• Lorentz force control = vector control
• AC current regulation
• IM slip and torque production

Application-Specific Selection of Machine-and-Drive Systems

• Load types and characteristics
• Specific drives to suit application
• Practical issues of machine and drive selection
• PM versus IM
• Installation considerations

Application of Wide Bandgap Devices to Power Electronics

• Review of Silicon Carbide (SiC) and Gallium Nitride (GaN) devices
• DC-DC converter example using SiC
• 2-level VSI using SiC and GaN inverters

High-Speed Electric Machines

• Review of high speed electric machines
• Sizing equation and definition of tip speed
• Pros and cons of each machine for high speed
• High-speed machine design considerations

Michael Harke

Michael received his BS, MS and Ph.D. in Mechanical Engineering from the University of Wisconsin – Madison in 1997, 1999 and 2006, respectively.  His research focused on control theory, electric machines and power electronics.  During his studies, he worked with numerous companies including Whirlpool, Ford Motor Company, Schneider Electric, International Rectifier and Hamilton Sundstrand.

 In 2006, Michael joined Hamilton Sundstrand in the Applied Research Department where he worked on control and power electronics for aerospace applications including motor drives and actuators.  Between 2010 and 2013 he was with Danfoss Power Electronics where he focused on industrial motor control.  He has since returned to Hamilton Sundstrand, now known as Collins Aerospace.  He is also an Adjunct Professor at the University of Rome La Sapienza, teaching coursework on dynamic analysis and control of ac machines.

 Michael is a member of the Institute of Electrical and Electronic Engineers where he serves as the Past Chair of the Industrial Drives Committee and society representative to the Sensors Council AdCom for the Industry Applications Society.  He was the Technical Program co-Chair for the IEEE Energy Conversion Congress and Exposition in 2013 and 2021.  He has published 25 papers in conferences and journals and has numerous patents.

Thomas Jahns

Dr. Thomas M. Jahns received his bachelors, masters, and doctoral degrees from MIT, all in electrical engineering.

Dr. Jahns joined the faculty of the University of Wisconsin-Madison in 1998 in the Department of Electrical and Computer Engineering.  He served for 14 years as a Co-Director of the Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC), a world-renowned university/industry consortium in the electrical power engineering field.  Since 2021, he is the Grainger Emeritus Professor of Power Electronics and Electrical Machines.

Prior to coming to UW-Madison, Dr. Jahns worked at GE Corporate Research and Development (now GE Global Research) in Niskayuna, NY, for 15 years, where he pursued new power electronics and motor drive technology in a variety of research and management positions. His current research interests at UW-Madison include integrated motor drives and electrified propulsion for both land vehicles and aircraft.

Dr. Jahns is a Fellow of IEEE.  He received the 2005 IEEE Nikola Tesla Technical Field Award “for pioneering contributions to the design and application of AC permanent magnet machines”.  Dr. Jahns is a Past President of the IEEE Power Electronics Society.  He was elected to the US National Academy of Engineering in 2015 and received the IEEE Medal in Power Engineering in 2022.

Phil Kollmeyer

Phillip Kollmeyer received the B.S., M.S., and PhD degrees in Electrical Engineering from the University of Wisconsin-Madison, in 2006, 2011, and 2015 respectively, with a focus on electric machines, power electronics, and controls.

As a graduate student, Phil built a prototype light-duty electric truck and led the development of a new energy storage test facility.  He also performed a range of projects on hybrid energy storage, battery aging, and battery and ultracapacitor modeling, and received two awards for his teaching in the electric machines and drives area.  Phil is currently a Senior Principal Research Engineer at McMaster University, Hamilton, ON, Canada.  He is the engineering lead for the team of 40 graduate students and post-doctoral fellows working on The Car of the Future Project, which is funded by Stellantis and Canada's Natural Sciences and Engineering Research Council.

Michael Ryan

Michael Ryan received his B.S. in Electrical Engineering from the University of Connecticut, Storrs,1988, M.E. degree in Electrical Engineering from Rensselaer Polytechnic Institute, Troy, NY, 1992, and Ph.D. in Electrical Engineering from the University of Wisconsin-Madison, 1997. At UW-Madison, Ryan worked in the WEMPEC labs on projects including dc–dc converters, variable-speed generation systems, and UPS inverter control.

Ryan is President of Ryan Consulting, involved in the application of Power Electronics and Controls, particularly for Alternative Energy systems. He has held prior positions at Capstone Turbine, General Electric Corporate Research and Development and Defense Systems divisions, Automated Dynamics, Otis Elevator, and Hamilton Standard.

Bulent Sarlioglu

Bulent Sarlioglu is a Jean van Bladel Associate Professor at University of Wisconsin—Madison, and Associate Director, Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC). Dr. Sarlioglu spent more than 10 years at Honeywell International Inc.’s aerospace division. As a staff system engineer, he earned Honeywell’s technical achievement award and an outstanding engineer award. Dr. Sarlioglu contributed to multiple programs where high-speed electric machines and drives are used mainly for aerospace and ground vehicle applications. Dr. Sarlioglu is the inventor or co-inventor of 20 US patents and many other international patents. He published more than 200 journal and conference papers with his students. His research areas are motors and drives including high-speed electric machines, novel electric machines, and application of wide bandgap devices to power electronics to increase efficiency and power density. He received the NSF CAREER Award in 2016 and the 4^th Grand Nagamori Award from Nagamori Foundation, Japan in 2019. Dr. Sarlioglu became IEEE IAS Distinguished Lecturer in 2018.  He was the technical program co-chair for ECCE 2019 and was the general chair for ITEC 2018.  He is serving as a special session co-chair for ECCE 2020.