LUP625  Electric drives SP3 and SP4 Spring 2022 (7.5 hp)

Course is offered by the department of Electrical Engineering

Examiner: Sonja Tidblad Lundmark , Associate Professor, PhD

Email: sonja.lundmark@chalmers.se

Phone: +46(0)31-772 1651

Division of Electric Power Engineering

Department of Electrical Engineering

Chalmers University of Technology

See Syllabus and Schedule in Syllabus LUP625_Jan_2022_including tutorial dates.pdf (The tutorial days are changed as seen below)

Schedule for the Tutorials and Practical Labs: See updated Schedule in Announcements New days/time for the tutorials and please sign up for the labs

Course Contents

The course menu is as follows:

1. Introduction to electric drive systems, primarily for a hybrid or electric vehicle application

2. Electric machine theory; steady-state and dynamic performance, assessments

3. Control engineering needed for the electric drive system control

4. Power electronics converters in drive systems in hybrid or electric vehicles (inverters, rectifiers and dc/dc converters), and pulse width modulation (PWM)

5. Motor/Drive selection criteria

The treated machine types are: dc-, permanent magnet synchronous-, asynchronous (induction), brushless dc-, switched reluctance, and synchronous reluctance machines. Special brushless dc-machines, like the axial flux and the transverse flux machines are treated briefly. Lectures and tutorials are given in conjunction with practical laboratory work and computer simulations.

Organisation
The course comprises of about 13 lectures, 9 tutorials, two practical (remote) laboratory exercises (2 x 2 h) and two computer labs. There is also a (not obligatory) trial exam. You are also expected to participate in discussion forums, regarding homework assignments in conjunction with some lectures.

Before coming to the remote lab, home assignments must be done, and the safety instructions must be read and understood. This will be tested before the labs can start.

The practical labs deal with the dc motor drive which is used as a model example and start point for other drives:

1.      Dc-motor: Determining dc-motor parameters

2.      Dc motor control: To implement a digital PI-regulator to control the speed of the dc machine in a Labview program and to perform a direct start of the DC motor.

The computer labs deal with:

1.      Dc-motor control: Simulations in Simulink and MATLAB regarding start of the dc machine, current and speed regulation etc

2.      PMSM-motor control: Building a model of a permanent magnet synchronous machine (PMSM) drive system in Simulink, including battery, inverter, motor and vehicle inertia and simulating current (torque) control

In the laboratory report, the results of the practical work and the simulations will be compared and discussed.

Personnel

Lecturs and tutorials: Associate Professor Sonja Lundmark (also examiner and coordinator)

Practical labs: TBD

Computer labs: PhD Student Artem Rodionov

Evaluation

The methods used to evaluate the students work in this course are:

1. Written examination (50%).
2. Approved laboratory exercises including a laboratory report (40%).
3. Homework assignments and participating in discussions (10%)

The relative weights of these methods are as follows (see also the Table below):

Students must achieve at least 50% in the laboratory mark to pass the course. Students must also achieve at least 40% in the written examination to pass the course. Lab tasks (totally 40 points) include a test conducted in conjunction with lab 2 (10 points), Lab report of the dc-lab (15 points) and computer lab 2 report (15 points).

Grades: Fail, 3, 4 or 5.

50-64 points G3          65-79 points G4         > 79 points G5

 

Trial exam (optional)	10 p
Lab report computer lab 1	15 p
Lab 2 test	10 p
Lab report computer lab 2	15 p
homework assignments and discussions	10 p
Final exam	50 p

Lectures and related course literature

Literature

Book of Hughes: Electric Motors and Drives, by A Hughes 3^rd or 4^th Edition, (or 5^th Edition)

Course Compendium: “Electric Power Engineering for General Motors” by Torbjörn Thiringer Course Compendium part I-GM_TEP.pdf Download Course Compendium part I-GM_TEP.pdf

Course Compendium part 2: “Course Compendium Part II for the course LUP 625 Electric Drives” by Sonja Lundmark. Course compendium part II.pdf Download Course compendium part II.pdf

Students are encouraged and expected to consult other books in the general area of Electric Drives.

Lectures

1. Introduction; Course information, introduction to motor drive systems in vehicles, the demands on the electrical machine in an electric or hybrid vehicle, revision of electrical machines basics. Book of Hughes Chapter 1
2. DC machines and experimental work introduction; dc motor components, commutation, speed control options, armature reaction, 4-quadrant operation and regenerative braking, losses. Book of Hughes Chapters 3 and 4
3. DC machines and experimental work introduction continuation and dc-computer lab introduction; Drives performance (controller and converter added), speed and current control and digital controlled drives. Course Compendium Chapter 1, 4, 6 and Section 3.2
4. Drive systems in electric and hybrid electric vehicles; Introduction to the drive system to be modeled in computer lab 2 and 3, power electronic converters, pulse width modulation. Course Compendium Chapter 2 and 3 and Book of Hughes Chapter 2
5. Synchronous machines; Rotating field, alignment torque and reluctance torque, pm synchronous motors, the switched reluctance machine, the synchronous reluctance machine (assessments, design criteria and mode of operation). Book of Hughes Chapters 5, 10
6. Permanent magnets and permanent magnet drives; permanent magnets characteristics and safety, materials, locations in the machine, effects of demagnetizing fields.Course Compendium part 2, Chapter 1

7. Permanent magnets and permanent magnet drives, including the brushless dc machine; brushless dc motor principle of operation, torque and emf calculations, torque-speed characteristics, special brushless dc machines (the axial flux and the transverse flux machines Course Compendium part 2, Chapter 2
8. The asynchronous machine; components, comparison to dc-machines and synchronous machines, operation (torque-speed curves, current-speed curves, rotor parameter and voltage reduction effects on maximum torque capability, speed control possibilities), demo of a machine direct start. Book of Hughes Chapters 5-8.
9. Core fabrications, core loss and windings. Course Compendium part 2, Chapter 3
10. General design aspects and motor drive selection criteria. Book of Hughes Chapters 11 and Course Compendium part 2, Chapter 4
11. The permanent magnet synchronous machine (PMSM) control; transformation to d-q system, machine equations, field-oriented vector control, introduction to computer lab 2. Course Compendium, Section1.17, Chapter 3 and Section 5.1
12. PMSM control continuation; Modelling of the drive system used in computer lab 2, performance, loss, efficiency. Course Compendium Chapter 5
13. Field-oriented control of the induction motor. Course Compendium Section 5.2.

Tutorials                                           

1. Ch.1 in course book   
2. DC machine and control        
3. Power electronic converters   
4. Synchronous machines and switched reluctance machines
5. PM design and PM drives      
6. Brushless dc-machines          
7. Asynchronous (induction) machines
8. Design aspects and motor drive selections and trial exam solutions
9. Revision and old exam problems

Assignments

Optional:

•  Optional homework exercises are provided with solutions by the Tutor who demonstrates and allows questions of homework problems at Tutorials
•  A trial exam (given after lecture 8) can give you 10 extra points
• Non graded quiz questions are provided in ping-pong (one quiz with general questions and one to help lab preparation). You can practice on those quizzes whenever you like, as many times as you like.

Compulsory:

• A lab report is to be handed in week 14 regarding practical labs and the DC motor computer lab.
• A report is to be handed in week 18 regarding PMSM computer labs.
• Practical lab homework exercises. Prepare yourself well before the lab!
•  2 compulsory homework exercises are given during the course with problems relating to lectures 6,7,8,9 and 10. Answers should be handed in as attached pdf document to a provided discussion forum in ping-pong. Thereafter, must every student make at least one thoughtful comment to another students answer to get a pass (give 10 points in total).

 

Assignment	Available	Hand-in	Feedback	Responsible teacher
Homework exercises are provided with solutions	According to the time schedule for tutorials	-	-	Sonja Lundmark
Homework exercises	When the corresponding lecture is available	Answers within 2 weeks and comment on another student’s hand-in within 2 more weeks	Two weeks after all hand-ins	Sonja Lundmark
Practical lab homework exercises	At course start	2 workdays before the lab occasion	Prior to the lab occasion	TBD
Lab report about practical labs and computer lab about the DC motor		Week 14	Week 16	Artem Rodionov
Computer lab about the PMSM	Week 16	Week 18	Week 20	Artem Rodionov

Aim

The overall aim of the course is to provide an understanding of the design, modeling and assessments of electric drive systems, primarily for a hybrid or electric vehicle application. The course will provide a deep understanding of electric machines: steady-state, and (for the dc-, induction and the permanent magnet synchronous machine) dynamic performance with speed and current control including relevant theory. The dc motor drive is used as a model example for other drives. Power electronics converters and control theory relevant to the electric drive systems in hybrid or electric vehicles are also treated. Further, an electric vehicle propulsion drive system is introduced and modeled, using field vector control. The student is encouraged to consider environmental aspects, such as energy-efficient drive systems.

Objectives

After the course the student will be able to:

• Describe the steps required for the design and implementation of an electric drive system and the demands on the electrical machine, primarily for a hybrid or electric vehicle application.
• Describe the assessments of the treated electric machines (mentioned below), the way of operation, relevant models, and general performance such as torque-speed curves.
• Recognize the appearance of the different machine types and know what the main parts look like and what kind of materials that can be used.
• Describe the performance and topology of power electronic converters, primarily for an electric vehicle application. Also describe how pulse width modulation works and can be used.
• Understand and follow safety instructions for the drive system lab used in the course.
• Describe the dynamic performance of the dc machine, the induction machine and the permanent magnet synchronous machine with the coupled electric and mechanic equations.
• Use the relevant models and perform simulations with Matlab/Simulink on direct start, current and speed control of the dc machine, connected to the supply via a thyristor converter (assumed ideal).
• Use the relevant models and perform simulations with Matlab/Simulink on vector field torque control of the permanent magnet synchronous machine.
• Compare simulations and experimental findings and document and present the work in a written report.
• Choose the relevant (environmentally friendly) drive system for an application with given specifications especially for hybrid or electric vehicles (like high speed, space requirements, price, efficiency, fault tolerance etc).