Advanced Protective Relaying Based on Rogowski Coil Current Sensors

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Advanced Protective Relaying Based on Rogowski
Coil Current Sensors
Ljubomir A. Kojovic Martin T. Bishop Cooper
Power System Thomas A. Edison Technical
Center Franskville, Wisconsin, USA
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Iron-Core Current Transformer
Rogowski Coil
Ip
Air Core
RB
M
IP
IS
IS
IP
IE
Lm
RB
RB
High Impedance Burden
Low Impedance Burden
VB
IS
? 0?
? 90?
IE
IP
IP
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V-I Characteristics
Non-Gapped Iron-Core Current Transformer
Voltage
No Air-Gap
Increasing Air-Gap
Air-Gap 1
Air-Gap 2
Linear Coupler
Operating point
Rogowski Coil
Current
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Design Criteria

• Relative Position of the Primary Conductor inside
  the Coil Loop
• The Impact of Nearby Conductors (external
  electromagnetic fields)

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Relative Position of the Primary Conductor inside
the Coil Loop
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External Electromagnetic Fields
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Designs
Interior Applications
Exterior Applications
Split-Core Type Rogowski Coil
Parallel Conductors
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Comparison to CTs
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Spot Networks
SN1
SN2
SN3
Rogowski Coil
Circuit Breaker
Network Protector
Fuse
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Integrated Relay Protection Solutions
Zone 1
Network 1
R
G
Zone 5
Network 2
Zone 4
Bus
Zone 2
Zone 3
Load
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Integrated Relay Protection Solutions
Zone 1
RC1
RC2
Network 1
R
G
Relay2
Network 2
Relay1
RC3
Load
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Integrated Relay Protection Solutions
Network 1
R
G
Network 2
Zone 2
RC1
RC2
Fiber Optic Cable
Relay1
Relay2
Load
other IEDs
Ethernet Switch
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Busbar Protection
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Traveling Wave Based Protection
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Traveling Wave Based Protection
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Field Experience with Differential Protection of
Power Transformers Based on Rogowski Coil
Current Sensors
Ljubomir A. Kojovic Martin T. Bishop Cooper
Power System Thomas A. Edison Technical
Center Franskville, Wisconsin, USA
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Differential Protection of Power Transformers
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Differential Protection of Power Transformers
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Differential Protection of EAF Transformers
Split-Core Rogowski Coil
Non Split-Core Rogowski Coil
EAF Transformer
Water Cooled Leads 50 kA 100 kA
Tap position
EAF
Multifunction Relay
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Differential Protection of EAF Transformers
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Differential Protection of EAF Transformers
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