# Electrical Machines-II

 Course Code : RT22025 Author : uLektz University : JNTU Kakinada Regulation : 2013 Categories : Electrical & Electronics Format : ePUB3 (DRM Protected) Type : eBook

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Description :Electrical Machines-II of RT22025 covers the latest syllabus prescribed by JNTU Kakinada for regulation 2013. Author: uLektz, Published by uLektz Learning Solutions Private Limited.

Note : No printed book. Only ebook. Access eBook using uLektz apps for Android, iOS and Windows Desktop PC.

##### Topics
###### UNIT-I SINGLE-PHASE TRANSFORMERS

1.1 Types and constructional details - principle of operation - emf equation - operation on no load and on load - lagging, leading and unity power factors loads

1.2 Phasor Diagrams Of Transformers – Equivalent Circuit – Regulation – Losses And Efficiency

1.3 Effect Of Variation Of Frequency And Supply Voltage On Losses – All Day Efficiency.

###### UNIT-II SINGLE-PHASE TRANSFORMERS TESTING

2.1 Tests on single phase transformers – open circuit and short circuit tests – Sumpner’s test – separation of losses

2.2 Parallel operation with equal voltage ratios

2.3 Auto Transformer - Equivalent Circuit – Comparison With Two Winding Transformers.

###### UNIT-III 3-PHASE TRANSFORMERS

3.1 Polyphase connections - Y/Y, Y/∆, ∆/Y, ∆/∆ and open ∆

3.2 Third harmonics in phase voltages

3.3 Three winding transformers: determination of Zp, Zs and Zt - transients in switching.

###### UNIT-IV 3-PHASE INDUCTION MOTORS

4.1 Construction details of cage and wound rotor machines

4.2 Production of a rotating magnetic field - principle of operation

4.3 Rotor Emf And Rotor Frequency-rotor Current And Pf At Standstill And During Running Conditions

4.4 Rotor Power Input, Rotor Copper Loss And Mechanical Power Developed And Their Inter Relationship-Equivalent Circuit – Phasor Diagram.

###### UNIT-V CHARACTERISTICS, STARTING AND TESTING METHODS OF INDUCTION MOTORS

5.1 Torque equation - expressions for maximum torque and starting torque

5.2 Torque slip characteristic - double cage and deep bar rotors

5.3 Crawling and cogging

5.4 No load and blocked rotor tests

5.5 Circle diagram for predetermination of performance

5.6 Methods of starting – starting current and torque calculations

5.7 Induction generator operation

###### UNIT-VI DESIGN OF TRANSFORMER AND 3-PHASE INDUCTION MOTOR

6.1 Transformer: Design concept – output equation

6.2 Choice of windings – calculation of number of turns- length of mean turn of winding - calculation of resistance and leakage reactance.

6.3 Three phase induction motor: Design concept