SMMA MOTOR & MOTION COLLEGE

Fundamentals of Brushless Motor Control
Course Outline

The purpose of this course is to provide fundamental concepts and knowledge necessary to design and apply DC and Brushless motor drives. This course is intended for design engineers and field application engineers in the motion control industry who wish to clarify basic principles. The course will also include brief discussion on the magnetic and mechanical structure of the various motor types to understand torque production mechanisms and to derive a circuit model. The content will cover most of the basic skills in designing brush and brushless DC motor drives including power electronic circuits, analog and digital motor control hardware, gate drive and feedback sensors, with particular, emphasis on motor control algorithms and servo systems. From the author's long experience in research and development of many types of drives, practical and useful procedures in selecting components and methods, rule-of-thumb design rules, performance vs cost trade-off etc., will be discussed.

COURSE OUTLINE

I. Motor Control Basics

A. Torque production mechanism in electric motors
B. Various motor types
C. Control of brushed DC motors
D. Brushless motors and electronic commutation
E. Other motor types

II. Power Electronics and Analog Motor Drives

A. Power electronics devices
B. Switch configuration and PWM
C. Gate drive design
D. Brushless motor controllers
E. 2Q and 4Q drive

III. Drive Configuration

A. Current limiting and bus current control
B. Feedback sensors
C. Sinusoidal drives
D. Phase current control
E. DSP's for motor drives

IV. Servo Systems and Motion Control

A. Servo systems fundamentals
B. PID and other velocity and position control algorithms
C. Mechanical resonance modeling and digital filtering technique
D. Motion profiles and system sizing (selection of motors and drives)
E. Dynamic model of brushless motors
F. Frame transformation and synchronous d-q frame model of motors
G. Angle advance control of brushless motors

V. New Technologies in Motor Control

A. Space vector modulation
B. Sensorless control
C. Modeling and simulation

About the Author

Dr. Dal Y. Ohm is president of Drivetech, Inc. a technical consulting firm specializing in motor control, drives and servo systems. He has more than 20 years of industrial and academic experience in research and product development in the fields of servo systems and control a various types of motors. His major area of interest includes motion control, digital control, and estimation, robotics, vector control, AC and DC motor drives and power electronics. He has more than 40 published articles and conference presentations in the above area. Prior to consulting, he was a Technical Director at Kollmorgen Motion Technologies Group and Principal Engineer at Baldor Electric Company. He has taught engineering courses (electric machines, robotics, digital control) at San Jose State University, Northwestern Polytechnical University and Cogswell Polytechnical College as Adjunct Professor for many years. He received his Ph.D. (1983) and M.S. (1980) degrees in Electrical Engineering from Texas A&M University..