This document discusses the brushless excitation system for synchronous generators. It begins with an introduction and objective to understand the principles, components, and operation of brushless excitation systems. It then provides an overview of the key components, which include the synchronous generator, stator, rotor, pilot exciter, main exciter, diode bridge, and automatic voltage regulator (AVR). The main concepts are the use of a permanent magnet generator and exciter to produce a DC current to power the main generator field via a diode bridge, with the AVR controlling the output voltage.

1. Brushless Excitation System for Synchronous Generators
By Adhithya, Anabhayan
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2. Motivation and Objective
Brushless excitation system most popular and advanced methods of
for excitation.
By the end: You should be, to understand the principles,
components, and operation of brushless excitation system for
synchronous generators.
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3. Synchronous Generator
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4. Nameplate details
Figure: Name plate details of NCTPS 800 MW unit
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5. Stator
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6. Stator
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7. Rotor
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8. Rotor
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9. Static/Brushed Exciter
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10. Brushless Exciter
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11. Pilot Exciter
Let’s start step by step, understanding the purpose of each
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12. Why high frequency?
Figure:
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13. Main exciter
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14. Main exciter + Diode Bridge
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15. Diode bridge
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16. Diode bridge in Generator
Figure:
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17. Diode bridge in Generator
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18. AVR as a whole + Control
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19. Power Plant control + Simulator
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20. Main Concepts
The main concepts and terms related to brushless excitation system are:
Permanent Magnet Generator (PMG): A small permanent magnet
generator that provides the power supply for the automatic voltage
regulator (AVR) and the exciter field.
Exciter: A small AC generator that produces the DC source for the
main generator.
Automatic Voltage Regulator (AVR): A controller that regulates
the output voltage of the main generator by adjusting the exciter field
current.
Diode Bridge: A rectifier circuit that converts the AC output of the
exciter to DC for the main generator field.
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21. Thanks and References
https://airgapflux.in/search?q=AVRAutomatic
Theodore Wildi Electrical machines
https:
//www.slideshare.net/superbhuppi/brushless-excitation
https://www.youtube.com/watch?v=qMy5DFCuoFk
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