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Industrial Systems
BUS2000 Busbar Differential Protection SystemDifferential overcurrent system with
percentage restraint protection
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Industrial Systems
Typical Busbar Arrangements– Single Busbar– Double Busbar with Coupler– Breaker and a Half– Double Breaker– Double Busbar with Transfer Bar– Segregated Busbars with Coupler
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Industrial Systems
Typical Single BusbarArrangement
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Industrial Systems
Typical Double Busbarwith Coupler Arrangement
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Industrial Systems
Typical Breaker and a Half Arrangement
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Industrial Systems
Typical Double BreakerBusbar Arrangement
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Industrial Systems
Typical Double Busbarwith Transfer Bar
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Industrial Systems
Typical Segregated Busbarwith Coupler
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Industrial Systems
Types of Protection Schemes
–Low Impedance–High Impedance
• Medium Values• High Values
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Industrial Systems
Low Impedance Protection
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Industrial Systems
Saturation of the AuxiliaryCTs
• A. Primary Fault Current• B. Secondary Current from the Source CTs• C. Secondary Current in the Faulty CT• D. Differential Current
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Industrial Systems
Low Impedance Protection Current Detection + Second
Criteria–Time-delayed Overcurrent Relays–Directional Overcurrent Relays –Restraint Overcurrent relays–CT Saturation Detectors
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Industrial Systems
High Impedance ProtectionScheme
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Industrial Systems
High Impedance Protection
•• WHERE:• RL= CONNECTION WIRES RESISTANCE• IF = SECONDARY RMS CURRENT VALUE IN TI3
• VR = DIFFERENTIAL RELAY VOLTAGE• VS = CT MINIMUM SATURATION VOLTAGE• VOP = OPERATION VOLTAGE
• VR = IF x (2RL + RS)• VOP > VR Stability Criteria• VS > VOP Operation Criteria• TI3 Totally Saturated• RS CT Secondary Winding R Value
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Industrial SystemsDifferential Overcurrent Relay with Percentage Restraint & Stabilizing
Resistor
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Industrial Systems
BUS2000-External Fault
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Industrial Systems
BUS2000-Internal Fault
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Industrial Systems
BUS2000 - Differential Unit Block Diagram
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Industrial Systems
BUS2000-Sensitivity Algorithm (1)
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Industrial Systems
BUS2000-Sensitivity Algorithm (2)
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Industrial Systems
BUS2000-Sensitivity Algorithm (3)
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Industrial Systems
External Fault with CT Saturation
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Industrial Systems
BUS2000-Stability Algorithm
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Industrial Systems
BUS2000-Stability Limit
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Industrial Systems
BUS2000-Operation Characteristic
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Industrial Systems
BUS2000-Auxiliary CT. Magnetizing Curve of the Secondary Side
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Industrial Systems
BUS2000-Alarm Unit Block Diagram
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Industrial Systems
Breaker Failure Block Diagram
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Industrial Systems
Numerical Monitoring Module– Differential and Restraint Currents Metering Information– Full Human-Machine Interface (Keypad + Graphic
Display)– IRIG-B Time Synchronization– Alarm Treatment– Differential Protection Outputs Status
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Industrial Systems
Numerical Monitoring Module (cont)
– Oscillography Waveform Capture– Event Record– RS232 or fiber optics Communications– Configurable I/O– Undervoltage Supervision
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Industrial Systems
BUS2000-Single Busbar(6 feeders) Differential Protection
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Industrial Systems
BUS2000-Overcurrent and Breaker Failure (5 feeders) Protection
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Industrial Systems
BUS2000-Test Rack
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Industrial Systems
BUS2000-Numerical Monitoring Module
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Industrial Systems
External Connections Diagram of Single Busbar BUS2000
System
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Industrial Systems
BUS2000-Settings–K for Sensitivity–K and RE as low as possible–RE for CT requirements for
Overvoltage Conditions
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Industrial Systems
Key Advantages
– Flexibility– Independent setttings for K and RE done in the field
without any additional changes– Wide Setting Range
– Suitable for all kinds of installations
– Measurement Units Supervision
– Current Circuits Supervision
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Industrial Systems
Key Advantages (cont’d)
– Single-Three Phase Breaker Failure– Test Rack Independent from the protection– Easy Commisioning (accesible terminal blocks)– Suitable for updating of old Substations– Operating Principles well proven in the field– Numerical Monitoring Module