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Unit information: Electric Propulsion Drives in 2020/21

Unit name Electric Propulsion Drives
Unit code EENGM0034
Credit points 20
Level of study M/7
Teaching block(s) Teaching Block 2 (weeks 13 - 24)
Unit director Professor. Phil Mellor
Open unit status Not open

EENG20002 Electromechanical Energy Conversion



School/department Department of Electrical & Electronic Engineering
Faculty Faculty of Engineering


This unit will study the design and operation of high-performance AC permanent magnet and induction motor electrical drives used in the electric propulsion of land and air vehicles, encompassing the power electronics, control and electrical machine components. During the unit, students will build a software tool for specifying and sizing an electrical machine drive and this will be used to explore case study electric vehicle, electric vertical take-off and landing air vehicle and other propulsion drive applications used in low carbon transport.

The equivalent circuits and defining equations that model the operation of AC permanent magnet and induction machines will be reviewed and mathematical descriptions of flux vector control methods for AC machines developed. Typical control and sensor feedback structures used in power electronic controlled AC drives will be derived. In tandem the fundamental electromagnetic behaviour of electrical machines will be reviewed and contextualised in terms of flux vector operation. Techniques used to size the magnetic circuit and the design of the windings of an AC electrical machine will be developed. The relationship between the electrical machine design and the inverter VA rating will be established to give an understanding of system level impact of design decision. Matlab/SIMULINK based drive system simulations and electrical machine design software will be used to inform this understanding.

Intended learning outcomes

Upon successful completion of the unit students will be able to:

  1. Explain the fundamental requirements that determine the specification and physical size of an electrical machine drive.
  2. Derive the bases of analytical techniques that are used in the design of AC windings, in the sizing of the magnetic circuit, and in the calculation of characteristic electrical parameters.
  3. Make informed choices of magnetic materials to be used in the design of electrical machines based on performance and cost constraints.
  4. Apply flux and current vectors to the operation of brushless AC machines.
  5. Recall the mathematical models used in the implementation of vector control in brushless AC permanent magnet and induction motor drives and describe the methods of implementation and simulation of vector control AC propulsion drives.
  6. Describe and compare various AC drive control techniques and the sensors needed.
  7. Examine how losses and their distribution are determined from the electrical machine operating point and the methods used in determining electrical machine thermal behaviour.
  8. Embody analytical techniques in a parametric design tool that can be used to specify system level electrical requirements and magnetically size an AC electrical machine stator to meet these requirements.

Teaching details

Teaching will be delivered through a combination of synchronous and asynchronous sessions, including lectures, practical activities supported by drop-in sessions, problem sheets and self-directed exercises.

Assessment Details

Design case study assignment (100%) (All ILOs)

The study will test the students understanding in applying the analytical techniques, design tools and simulation models developed in the unit to an exemplar propulsion drive.

Reading and References

Mohan, N. Underland, J.M. and Robbins, W. Power Electronics:Converters, Applications & Design (3rd edition 2003), ISBN:0-471-42908-2.

Krishnan, R. Electric Motor Drives Modeling, Analysis and Control, ISBN:0-13-0910147, Prentice Hall.

Bose, B.K. Modern Power electronics and AC Drives, ISBN:0-13-016743-6, Prentice Hall.

Drury, W. (Editor), The Control Techniques Drives and Control Handbook Institution of Engineering and Technology (Jul 2001), ISBN-10: 0852967934.

Miller, T.J.E., Brushless Permanent Magnet and Reluctance Motor Drives (Electrical & Electronic Engineering Monographs), ISBN-10: 0198593694, ISBN-13 978-019853690, Clarendon Press.

Vas, Peter, Vector Control of Alternating Current Machines (Electrical & Electronic Engineering Monographs), ISBN-10 0198593708, ISBN-13 978-0198593706, Clarendon Press.

Fitzgerald, Kingsley and Urmans, ’Electrical Machinery’, 6th Addition, McGraw Hill, ISBN 0071230106