This course is intended to provide a basic introduction to the theory of magnetic circuits linked with transformers and rotating electrical machines. The principles of electromechanical energy conversion will be discussed in the context of DC machines. An indepth analysis of DC generators and motors will be carried out for different characteristics.
Prerequisite: NIL
Catalog Data: Course Code: ET215
Course Title: Electrical MachinesI (Th.)
Credit Hours: 3
Course Designation: Engineering Technology Foundation
No of Sessions per week: 1 (Total 16 sessions)
Session Duration: 180 min
Time of Class Meeting: 11:00 AM to 02:00 PM (Monday)
Program Learning Outcome:
This course is designed in conjunction with the following PLOs.
PLO 1. Engineering Knowledge: An ability to apply knowledge of mathematics, science, engineering fundamentals and an engineering specialization to the solution of complex engineering problems.
PLO 2. Problem Analysis: An ability to identify, formulate, research literature, and analyze complex engineering problems reaching substantiated conclusions using first principles of mathematics, natural sciences and engineering sciences.
Course Learning Outcome (CLO):
Upon successful completion of this course, the student will be able to:
CLO 1. Apply the concepts of magnetic circuits for the performance evaluation of electrical machines [CognitiveLevel 3 (Applying)]
CLO 2. Evaluate the operation and characteristics of DC machines. [CognitiveLevel 5 (Evaluating)]
CLO 3. Analyze the performance of transformers and threephase machines. [CognitiveLevel 5 (Evaluating)]
Textbook:
References:
Evaluation Criteria:
COURSE DISTRIBUTION ON WEEKLY BASIS
Weeks 
Topics 
Quiz/ Assignment 
WEEK 01 TO WEEK 05 
Introduction to Magnetic Circuits 
CLO1 Chapter 1 (Chapman & Fitzgerald) 
WEEK 06 
DC Generator: Construction, Types of DC generators, separately excited generator, shunt generator, voltage buildup phenomenon, series generator, compounded generator and its type; under compounded, over compounded and flat compounded generator, terminal characteristics of all the generators. 
CLO2 (Chapman 7.3, 7.4 and Lecture Notes)
Assignment 1 
WEEK 07 
Armature Reaction: Concept of magnetic and magnetic neutral axis, placement of carbon brushes, armature reaction and its causes, components of armature reaction, effects of armature reaction, remedies for armature reaction (compensating winding, flux enhancement and brush shifting). 
CLO2 (Chapman 7.4 and Lecture Notes)
Quiz 1 
WEEK 08 
Commutation: One Commutation process, commutation time, ideal commutation, poor commutation, effects of poor commutation, practical difficulties, Ldi/dt effect, interpoles, function of interpoles. Losses: Different types of losses and their formulation, power flow diagram of motor and generator, calculation of maximum efficiency, calculation of losses at different loads circuit. 
CLO2 (Chapman 7.4, 7.7 and Lecture Notes) 
WEEK 08 
MidTerm 
CLO1CLO2 
WEEK 09 to WEEK 10 
DC Motors: Working principle, construction and operation, different types of DC motors, Back e.m.f equation, torque equation, terminal characteristics of separately excited and shunt type DC motor. Series and parallel combinations 
CLO2 (Chapman 8.1 to 8.4) 
WEEK 11 
Speed Control of DC Motor: Base speed, speed control of DC motors especially shunt type and separately excited machine, voltage control method, field current control method, effects of open field, permanent magnet machines. 
CLO2 (Chapman 8.4 to 8.5) 
WEEK 11 
DC series motor: Expression for torque, applications, terminal characteristics, methods for speed control. 
CLO2 (Chapman 8.6) 
WEEK 12 to WEEK 13 
Transformer: Basic principal and operation, types and construction, applications, ideal and practical transformer and their comparison; voltage and current transformation, impedance matching, dot convention. 
CLO3 (Chapman 2.1 to 2.4) 
WEEK 14 
Auto Transformers: Basic principle, construction and working, voltage and current relationship, apparent power rating advantage of auto transformers. Three phase transformers: Types, ratings, different type of connections. 
CLO3 (Chapman 2.9 and Lecture Notes) 
WEEK 15 
Losses: Different types of losses and their formulation, power flow diagram of motor and generator, calculation of maximum efficiency, calculation of losses at different loads circuit. 
CLO2 (Chapman 7.4, 7.7 and Lecture Notes) 
WEEK 16 
Transformer Tests and Voltage Regulations: Open circuit Test and calculations of magnetizing branch parameters, short circuit test and calculation of impedance, Voltage regulation, reasons of voltage drops, and voltage regulation under different load conditions. 
CLO3 (Fitzgerald 2.5 and Chapman 2.7 and 2.8)

WEEK 17 
Revision 

WEEK 18 
Final Examination 
CLO1 to CLO3 