excitation system for alternator
TRANSCRIPT
STUDY OF DIFFERENT TYPES OF EXCITATION
SYSTEM FOR ALTERNATOR
SANTU SUTRADHAR ROLL NO- 10201615071 ELECTRICAL ENGINEERING
SUBMITTED BY :
Power Point Representation on
KALYANI GOVT. ENGINEERING COLLEGEKALYANI : NADIA
2
CONTENTS Alternator Excitation System Function Of Excitation System Types Of Excitation System Description Of Each Type Conclusion Reference
KGEC/EE 14/7/2016
3
ALTERNATOR
It Is An Electrical Machine Which Converts Mechanical Power Into Electrical Power By
The Principle Of Electro-magnetic Induction.
Alternators Are The Primary Source Of All The Electrical Energy We Consume And Also
The Largest Energy Converters. KGEC/EE 14/7/2016
4
STATOR
ROTOR
3 PHASE SUPPLY
ALTERNATOR
KGEC/EE 14/7/2016
5
EXCITATION SYSTEMThe Process Of Creating And Strengthening The Magnetic Field Of The Alternator By Providing The Necessary Direct Current To The Field Winding Of The Alternator
THE DIRECT CURRENT IS SUPPLIED TO THE ROTOR BY A SEPARATE D.C. SOURCE, CALLED EXCITER.
KGEC/EE 14/7/2016
6
FUNCTION OF EXCITATION
Supply Direct Current To the Field Winding For Creating Magnetic Field
Control Voltage & Reactive Power
Perform Protective Function
KGEC/EE 14/7/2016
7
TYPES OF EXCITATION SYSTEM
1. DC Excitation System
2. AC Excitation System
3. Static Excitation System
KGEC/EE 14/7/2016
8
D.C. EXCITATION SYSTEMTWO SMALL D.C.GENERATORS ARE USED AS EXCITERS.
D C EXCITATION SYSTEM
It is the oldest of all. Due to various problem now a days it is not conventionally used for large alternators
KGEC/EE 14/7/2016
9
A.C. EXCITATION SYSTEMIt Consists Of A.C. Generator And Thyristor Rectifier
Bridge Directly Connected To The Alternator Shaft or driven by separate motor.IT IS OF TWO TYPES
1. BRUSHLESS EXCITATION SYSTEM
2. ROTATING THYRISTOR EXCITATION SYSTEM
Main exciter is separately excited
Main exciter is self excited
KGEC/EE 14/7/2016
10
BRUSHLESS EXCITATION SYSTEM Elimination of brush & slip rings Less maintenance Fast response time
Suitable For Higher Rating Alternator
KGEC/EE 14/7/2016
11
Schematic Diagram
D.C.
A.C.
A.C.D.C.
KGEC/EE 14/7/2016
12
ROTATING THYRISTOR EXCITATION SYSTEM
D.C. A.C.D.C.
A.C
.D.C .
KGEC/EE 14/7/2016
13
STATIC EXCITATION SYSTEMThere Is No Rotating Part In This Excitation System. So No Windage Loss & Small Size.
Suitable For Medium & High Capacity Alternator
KGEC/EE 14/7/2016
14
Circuit Diagram
A.C.
D.C.
A.C.
KGEC/EE 14/7/2016
15
CONCLUSION
Selection of excitation system depends on various factors Alternator Power Alternator Size Alternator Speed Maintenance Cost
KGEC/EE 14/7/2016
16
Theory & Performance of Electrical Machine by J.B. Gupta https://www.quora.com https://www.youtube.com https://www.eblogbd.com
KGEC/EE 14/7/2016
REFERENCES
THANK YOU
DEPARTMENT OF ELECTRICAL ENGINEERING
KGEC/EE 14/7/2016