ECE 330
Power Circuits and Electromechanics

Section Type Times Days Location Instructor
C DIS 1000 - 1050 M W F   2017 Electrical & Computer Eng Bldg  Peter Sauer
N DIS 1400 - 1450 M W F   2017 Electrical & Computer Eng Bldg  Kiruba Haran
Web Page
Official Description Network equivalents; power and energy fundamentals, resonance, mutual inductance; three-phase power concepts, forces and torques of electric origin in electromagnetic and electrostatic systems; energy conversion cycles; principles of electric machines; transducers; relays; laboratory demonstration. Course Information: Prerequisite: ECE 210.
Subject Area Power and Energy Systems
Course Prerequisites Credit in ECE 210
Course Directors Peter W Sauer
Detailed Description and Outline

To provide an introduction to three phase circuits, transformers, and electromechanical systems with emphasis on analysis and some design insight.


  • Complex and reactive power in single- and three-phase circuits (6 hrs)
  • Magnetic circuits and transformers (6 hrs)
  • Energy conversion principles (6 hrs)
  • Electromechanical systems (6 hrs)
  • Synchronous machines (6 hrs)
  • Induction machines (6 hrs)
  • DC and single-phase machines (6 hrs)

Credit is not given toward graduate degrees in Electrical and Computer Engineering.

Computer Usage
Two homework problems in numerical solution of power circuits and electromechanical systems.
Topical Prerequisities
  • Basic circuit analysis
  • Maxwell's equations
  • Differential equations

M. A. Pai, Power Circuits and Electromechanics, Champaign: Stipes, 2006.
Class notes.

ABET Category
Engineering Science: 90%
Engineering Design: 10%
Course Goals

This is one of the technical electives (3 out of 5) in the EE curriculum. The goals are to impart basics of three phase power circuits, transformers and electromechanical systems with an emphasis on rotating machines. This addresses the ECE department Program Educational Objectives to provide depth, breadth, and learning environment.

The letters (a)-(n) refer to ABET Criterion 3 as follows:

(a) Ability to apply knowledge of mathematics, science, and engineering

(b) Ability to design and conduct experiments as well as to analyze and interpret data

(c) Ability to design a system to meet desired needs within realistic constraints such as economic, environmental, social, political, ethical, health and safety, manufacturability, and sustainability

(d) Ability to function on multidisciplinary teams

(e) Ability to identify, formulate, and solve engineering problems

(f) Understanding of professional and ethical responsibility

(g) Ability to communicate effectively

(h) Broad education necessary to understand impact of engineering solutions in a global, economic, environmental, and societal context

(i) Recognition of the need for and ability to engage in lifelong learning

(j) Knowledge of contemporary issues

(k) Ability to use the techniques, skills, and modern engineering tools necessary for engineering practice

(l) Knowledge of probability and statistics, including applications to electrical/computer engineering

(m) Knowledge of mathematics, and basic and engineering sciences, necessary to carry out analysis and design appropriate to electrical/computer engineering

(n) Knowledge of advanced mathematics

A. At the end of three weeks of classes the students should be able to analyze single and three phase sinusoidal balanced circuits (a, k). This includes being knowledgeable in the following topics:

  • Phasors; r.m.s. values; peak values; phase angle
  • power factor (leading (capacitive) or lagging (inductive))
  • complex power; real and reactive power; lagging and leading power factor
  • apparent power (volt amps); rated VA; rated volts; rated amps
  • use of phasors to calculate all complex power variables
  • conservation of complex power
  • Y and D connections; line and phase voltages and currents for Y and D connections
  • Y-D transformation (balanced only); power in 3-phase circuit, per phase calculations
  • Improvement of power factor

B. At the end of six weeks of classes, the students should be able to analyze magnetic circuits (a, c, e, k, m, n). This includes being knowledgeable in the following topics:

  • flux (f), magneto-motive force (MMF) (Ni); reluctance (Â)
  • calculation of fluxes; flux linkages and inductances (self and mutual)
  • coefficient of coupling for coupled coils; polarity dot marking; coupled coil equations
  • ideal transformers; transformer equivalent circuits
  • current, voltage and impedance relations for transformers
  • losses in transformers; efficiency,
  • approximate transformer equivalent circuits; voltage regulation
  • open and short circuit tests to determine transformer parameters

C. At the end of nine weeks of classes, the students should understand basic principles of electromechanical energy conversion, compute forces and torques of electric origin in magnetic devices such as relays, transducers etc. (a, b, e, k, m, n). This includes being knowledgeable in the following topics:

  • flux linkage (self and mutual); use of magnetic circuits to calculate flux linkages
  • calculation of energy Wm (path of integration); use of energy to calculate fe
  • use of energy to calculate Te; calculation of co-energy
  • calculation of co-energy (paths and integration)
  • fe and Te using co-energy (single and multiple terminal pair systems)
  • dynamics of lumped mechanical systems

D. At the end of twelve weeks of classes, the students should be able to Simulate numerically simple electromechanical systems and find the stability of the equilibria. (a, e, k, m, n). This includes being knowledgeable in the following topics:

  • nonlinear dynamic model; static equilibrium points
  • dynamic equations of motion; graphical method of computing equilibrium points
  • state space formulation
  • Euler’s method to integrate non-linear differential equations (numerical)
  • linearization of dynamic equations and stability of static equilibrium points

E. By the end of the semester the student should be able to analyze the basic steady-state operation of synchronous machines, induction machines and DC machines (a, c, k). This includes being knowledgeable in the following topics:

  • form of flux linkages; calculation of torque,
  • per-phase equivalent circuit; power relations; motor and generator operation
  • multiple pole machines-speed of operation
  • power and efficiency calculations; torque-speed curves

Last updated: 2/18/2013