Design of Electric Machinery

Course Description

Basic principles of design and construction of electrical machines. Design algorithm. Selection of electrotechnical materials for constructions of machines and devices. Determination of main dimensions of transformers, induction machines and synchronous machines. Scaling laws in construction of electrical machines. Calculation of magnetic circuit and electric machine parameters. Capability curves, losses and efficiency. Choice of the cooling method. Thermal equivalent circuit and basic calculation of heat distribution. Computer aided design. The application of 2D and 3D finite element method in the machine design. Principles of optimization in the design. The use of standards and regulations in the design process.

General Competencies

Knowledge of electric machine design based on technical specifications and demands. Basic knowledge of thermal and mechanical limitations in construction and exploitation of electrical machines. Ability to utilize standards and regulations in electrical industry and utility. Capability of creating an electric machine design.

Learning Outcomes

  1. describe the structure of transformers and rotating machines
  2. identify the types of cooling, mechanical protection and construction of transformers and rotating machines
  3. explain the principles of design in electrical machinery
  4. calculate the main dimensions of transformers and rotating machines
  5. analyze the impact of the choice of parameters of an electric machine on the output characteristics
  6. relate characteristics of the magnetic circuit with parameters of an electric machine model

Forms of Teaching

Lectures

Lectures take place in two cycles: the first cycle lasts for 7 weeks with 2 hours per week, and the second cycle lasts for 6 weeks with 2 hours per week.

Laboratory Work

Laboratory exercises are held in the period of three weeks in the second cycle with duration of 3 hours per week.

Seminars

The seminar consists of creating an electromagnetic design of either a transformer, a synchronous machine or an induction machine

Grading Method

Continuous Assessment Exam
Type Threshold Percent of Grade Comment: Percent of Grade
Laboratory Exercises 0 % 30 % 0 % 30 %
Seminar/Project 0 % 40 % 0 % 40 %
Mid Term Exam: Written 0 % 20 % 0 %
Final Exam: Oral 10 %
Exam: Oral 30 %

Week by Week Schedule

  1. Definition of the design problem. Conditions and limitations in the design considering the properties of materials and utilization of international and national standards.
  2. Magnetic circuit of an electrical machine. Main and leakage flux. Reluctances of the magnetic circuit.
  3. Determination of main dimensions of the magnetic circuit. Electrical and magnetic limitations considering the allowed heating and saturation of the magnetic circuit. Nonlinearity of the magnetic circuit. The use of scaling laws in the design.
  4. Types of electric machine windings. Magnetomotive force, linear current density and air gap field distribution. Induced voltage.
  5. Electromagnetic forces and torques. Main and leakage inductances
  6. Calculation of winding and core losses. Mechanical losses. Efficiency.
  7. Heating of the machine and heat transfer. Thermal equivalent circuit. Calculation of winding and core temperatures.
  8. Mid-term exam
  9. Basic design of a power transformer
  10. Determination of principal dimensions of hydrogenerators and turbogenerators.
  11. Electromagnetic design of an induction machine
  12. Permanent magnet machine design
  13. Fundamentals of finite element method. Numerical calculation of torque, induced voltage and electric machine parameters.
  14. Structure of a computer program for an electric machine design. Flow chart. Iterative calculation procedure and criterions of convergence. Optimization methods, cost functions and constraints in electric machine design.
  15. Final exam

Study Programmes

University graduate
Electrical Engineering Systems and Technologies (profile)
Specialization Course (2. semester)

Literature

T.A. Lipo (2004.), Introduction to AC Machine Design, WisPERC, University of Wisconsin - Madison, USA
M. Ramamoorty (1998.), Computer - Aided Design of Electrical Equipment, Halsted Press New York, NY, USA
S. J. Salon (1995.), Finite Element Analysis of Electrical Machines, Kluwer Academic Publishers, USA
Vlado Ostovic (1994.), Computer-Aided Analysis of Electric Machines: A Mathematica Approach, Prentice Hall
Juha Pyrhönen, Tapani Jokinen, Valéria Hrabovcová (2008.), Design of Rotating Electrical Machines, John Wiley & Sons, Ltd

Grading System

ID 127431
  Summer semester
4 ECTS
L1 English Level
L1 e-Learning
30 Lecturers
15 Exercises
12 Laboratory exercises

General

90 Excellent
80 Very Good
70 Good
60 Acceptable