ABB SYNCHROTACT 6 SYN6302 Automatic Synchronizing Relay

Description

1. Core Overview & Positioning

2. Key Features & Functions

• Fully Automatic Synchronization:​ Continuously measures voltage, frequency, and phase angle of both sides (Generator and Busbar). It calculates the difference and, when all conditions are met, issues a close command to the circuit breaker at the precise moment for a smooth connection.
• Advanced Synchronization Modes:
  • Generator to Busbar (Standard).
  • Busbar to Busbar (Check Synchronizing).
  • Dead Busbar Closing:​ Allows closing onto a de-energized bus (dead bus) or a bus with residual voltage (live bus logic).
• Intelligent Control Strategies:
  • Can send raise/lower pulses​ to the generator’s governor (for speed/frequency matching) and raise/lower pulses​ to the Automatic Voltage Regulator (AVR) (for voltage matching).
  • Features adaptive control algorithms for efficient and fast synchronization.
• Integrated Protection & Safety Functions:
  • Sync-Check (ANSI 25):​ Permissive function to prevent closing if conditions are not met.
  • Voltage Differential Protection (ANSI 60):​ Protects against closing with excessive voltage difference.
  • Built-in safety timers and interlocks​ to prevent repeated failed attempts.
• User Interface & Configuration:
  • Front-panel LCD display​ and navigation keys for local operation, real-time parameter viewing (slip frequency, phase angle, voltage difference), and setting adjustments.
  • Configured using dedicated software (e.g., CAP 505​ or PCM600) for detailed parameterization.
• Communication:​ Equipped with communication ports (RS485, Ethernet) supporting standard protocols like Modbus RTU/TCP, IEC 61850, for integration into plant DCS/SCADA systems.

3. Common Technical Specifications

• Voltage Inputs:​ Typically two three-phase voltage inputs​ (for Generator side and Busbar side). Common nominal voltages: 100-120V AC or 200-240V AC (via VTs).
• Frequency Range:​ Wide operating range (e.g., 40-70 Hz).
• Synchronizing Accuracy:​ High-precision closing, typically < ±2°​ phase angle and < 0.3 Hz​ frequency difference at the moment of closing.
• Output Relays:​ Multiple programmable output relays for:
  • Close Command​ (pulsed output).
  • Raise/Lower Governor.
  • Raise/Lower AVR.
  • Alarms and Status signals.
• Binary Inputs:​ For external commands (Start Sync, Enable, Block) and status feedback.
• Power Supply:​ Wide-range DC or AC supply (e.g., 24-48 V DC, 110-230 V AC/DC).
• Mounting:​ DIN-rail or panel mounting.

4. System Integration

• Role in a Generator Control System:​ It works in conjunction with the Governor​ (speed control) and Automatic Voltage Regulator (AVR). Upon a start command, it takes over the fine-tuning of frequency and voltage before issuing the final closing command.
• Typical Wiring:​ Connects to:
  • Voltage Transformers (VTs) on the Generator and Busbar.
  • Circuit breaker’s closing coil.
  • Governor and AVR raise/lower interfaces.
  • Plant control system via communication or hardwired I/O.
• Commissioning:​ Requires careful setting of parameters such as allowable voltage difference, frequency difference (slip), phase angle window, circuit breaker closing time, and pulse durations for governor/AVR control.

5. Typical Applications

• Power Plants:​ Synchronizing diesel, gas, hydro, or steam turbine generators to a plant bus or the utility grid.
• Industrial Plants:​ For cogeneration (CHP) generators connecting to the factory electrical system.
• Marine & Offshore:​ Synchronizing generator sets on ships or offshore platforms.
• Utility Substations:​ For busbar coupling or line synchronization.