JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Prerequisites

Electrical Machines (DC and AC), control theory

Course Objectives:

• To comprehend the basic two-pole machine.
• To identify the methods and assumptions in modeling of machines.
• To write voltage and torque equations for different machines.
• To recognize the different frames for modeling of different AC machines.
• To express the voltage and torque equations in State space form

Course Outcomes

Upon the completion of the course the student will be able to

• Write the voltage equation and torque equations for different machines like dc machine, induction motor and Synchronous machines.
• Model different machines using phase and Active transformations.
• Identify the different reference frames for modeling of machines.

UNIT - I

Basic Two-pole DC machine - primitive 2-axis machine – Voltage and Current relationship – Torque equation.

UNIT - II

Mathematical model of separately excited DC motor and DC Series motor in state variable form – Transfer function of the motor - Numerical problems. Mathematical model of D.C. shunt motor D.C. Compound motor in state variable form – Transfer function of the motor - Numerical Problems

UNIT - III

Liner transformation – Phase transformation (a, b, c to α, β, o) – Active transformation (α .β, o to d, q). Circuit model of a 3 phase Induction motor – Linear transformation - Phase Transformation – Transformation to a Reference frame – Two axis models for induction motor. dq model based DOL starting of Induction Motors.

UNIT - IV

Voltage and current Equations in stator reference frame – equation in Rotor reference frame – equations in a synchronously rotating frame – Torque equation - Equations I state – space form.

UNIT - V

Circuits model of a 3ph Synchronous motor – Two axis representation of Syn. Motor. Voltage and current Equations in state – space variable form – Torque equation. dq model based short circuit fault analysis- emphasis on voltage, frequency and recovery time.

TEXT BOOKS:

• 1. Analysis of electric machinery and Drive systems- Paul C. Krause , Oleg Wasynezuk, Scott D. Sudhoff, third edition, IEEE press
• 2. Generalized Machine theory P.S. Bimbhra, Khanna Publishers, 2002

REFERENCES:

• 1. Thyristor control of Electric Drives - Vedam Subramanyam, Tata McGraw-Hill Education, 1988
• 2. Power System Stability and Control – Prabha Kundur, EPRI.