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Chapter 17
Electric Utility Applications
• These applications are growing rapidly
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-1
HVDC Transmission
• There are many such systems all over the world
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-2
HVDC Poles
• Each pole consists of 12-pulse converters
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-3
HVDC Transmission: 12-Pulse Waveforms
• Idealized waveforms
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-4
HVDC Transmission: Converters
• Inverter mode of operation
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-5
Control of HVDC Transmission System
• Inverter is operated at the minimum extinction
angle and the rectifier in the current-control mode
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-6
HVDC Transmission: DC-Side Filters
Tuned for the lowest (12th
harmonic) frequency
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-7
HVDC Transmission: AC-Side Filters
Tuned for the lowest (11th
and the 13th harmonic)
frequencies
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-8
Effect of Reactive Power on Voltage
Magnitude
• Illustration of the basic principle
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-9
Thyristor-Controlled Inductor (TCI)
• Increasing the delay angle reduces the reactive
power drawn by the TCI
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-10
Thyristor-Switched Capacitors (TSCs)
• Transient current at switching must be minimized
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-11
Instantaneous VAR Controller (SATCOM)
• Can be considered as a reactive current source
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-12
Characteristics of Solar Cells
• The maximum power point is at the knee of the
characteristics
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-13
Photovoltaic Interface
• This scheme uses a thyristor inverter
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-14
Harnessing of Wing Energy
• A switch-mode inverter may be needed on the
wind generator side also
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-15
Interface with 3-Phase Utility Grid
• Uses a thyristor inverter
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-16
Interface of SMES
• Can be used for utility load leveling
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by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-17
Active Filters for Harmonic Elimination
• Active filters inject a nullifying current so that the
current drawn from the utility is nearly sinusoidal
Copyright © 2003
by John Wiley & Sons, Inc.
Chapter 17 Electric
Utility Applications
17-18