I. Basic Information

II. Technical Specifications

(1) Basic Hardware Parameters

• Brand: ABB | Origin: Sweden
• Type: Fully Digital Redundant Automatic Generator Precise Synchronizer
• Compatible Systems: Full-range UNITROL excitation devices, System800xA DCS and auxiliary power monitoring systems for power plants
• Application Scenarios: Thermal power generating units, hydropower units, captive power plants for chemical industry, cogeneration units and bus tie synchronization for substations
• Mounting: Standard DIN rail mounting inside control cabinet plus embedded cabinet installation
• Overall Dimension: 220mm(W)×150mm(H)×80mm(D), Net Weight: 1.8kg
• Protection Class: IP20 (for indoor cabinet installation)

• Hardware Architecture: Dual heterogeneous processor framework (two sets of main control ICs from different manufacturers with independent firmware programs); high-precision FPGA phase sampling circuit; fully enclosed PCB with three-proof coating for moisture and corrosion resistance

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(2) Rated Electrical Parameters

• Operating Power Supply: DC24V±15%, total power consumption ≤18W; built-in protection against reverse polarity, surge and overvoltage of power supply
• Synchronizing Voltage Sampling: AC100V (standard PT secondary rated voltage); accepts dual input voltages from generator terminal PT and grid PT
• Applicable Frequency Range: 45～65Hz, auto-adaptive for 50Hz/60Hz power grids
• Closing Output: Passive relay contact output with single-contact rating AC250V/5A, directly driving closing circuit of grid-connected circuit breakers

• Electrical Isolation: 2kV galvanic isolation across sampling circuit, control circuit and communication circuit to prevent equipment damage caused by high-voltage intrusion from PT circuits

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(3) Measurement, Control & Synchronization Performance Parameters

• Synchronization Accuracy: Phase closing error ＜0.1° electrical angle, frequency difference control precision 0.001Hz, voltage difference precision 0.2% Un; captures synchronization window within millisecond-level accuracy.
• Parameter Storage: 7 groups of independent grid connection parameters pre-stored onboard to save setting values for 7 separate units or 7 synchronization intervals, enabling one-click working condition switching.
• Speed & Voltage Regulation Interface: Multi-channel analog + digital output terminals to automatically interface with excitation AVR and turbine governor, adjusting unit frequency and voltage to approach grid parameters automatically.

• Interlock Logic: Automatic closing interlock upon excessive frequency deviation, voltage deviation or phase offset to avoid non-synchronous grid connection and consequent impact damage to generators and power grid.

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(4) Communication Interface Parameters

• LON Fieldbus: Standard onboard LON port for connection to ABB System800xA upper system to realize remote monitoring, remote parameter downloading and fault uploading.
• RS485 Serial Port: Modbus-RTU protocol for interconnection with third-party DCS and background monitoring systems.

• Local Debug Port: RS232, cooperating with SynView upper debugging software for online oscillography, parameter configuration and event record reading.

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(5) Environmental Specifications

• Operating Temperature: -25℃～+70℃, adaptable to seasonal temperature variation in power rooms and cabinet temperature rise
• Storage Temperature: -40℃～+85℃, resistant to extreme temperature shocks during long-distance transportation and storage
• Operating Humidity: 5%～95% RH (non-condensing), suitable for dusty and humid environment of power plant control rooms
• EMC Compliance: IEC61000-6-2 industrial EMC standard, immune to strong electromagnetic interference from excitation transformers and variable-frequency equipment

III. Key Features

Quadruple Redundant Safety Architecture Ensures Zero Outage During Grid Synchronization

Dual-mode Synchronization: Fully Automatic + Manual

• Fully Automatic Mode: The device automatically executes speed/voltage regulation → synchronization window capture → accurate closing pulse output;
• Manual Mode: Only synchronism interlock verification is implemented; closing command is blocked automatically once parameters exceed allowable tolerance to eliminate man-made wrong non-synchronous paralleling.

Partitioned Storage for 7 Parameter Groups Enables Multi-interval Reuse

A single unit supports parameter configuration for 7 different synchronization intervals. Multiple generating units at captive power plants can share one synchronizer to save cabinet space and procurement cost.

Full-range Protection Against Abnormal Grid Connection

Event & Fault Oscillography Storage

Direct Drop-in Replacement for Legacy Equivalent Series Products

IV. Working Principle

1. Power-on Self-test & Initialization: After DC24V energization, full self-check is executed for four independent sampling channels, processors and output loops. Upon successful verification, preselected grid connection parameter set is loaded and the unit enters standby sampling mode.
2. Dual-channel Voltage & Frequency Collection: Real-time sampling of AC voltages from generator terminal PT and grid PT to calculate amplitude, frequency and phase differences between the two sides.
3. Automatic Regulation Command Output: Speed-up/slow-down pulses are sent to turbine governor for excessive frequency deviation; voltage adjustment signals are transmitted to UNITROL excitation AVR for excessive voltage deviation to gradually align unit parameters with grid specifications.
4. Synchronization Window Prediction & Closing Control: The unit predicts the arrival of synchronous point and outputs closing pulse in advance to compensate inherent closing delay of circuit breaker, realizing precise zero-crossing phase grid connection.
5. Fault Interlock & Alarm: Closing output is blocked immediately upon parameter overrun or circuit disconnection; front-panel fault indicator lights up with corresponding fault code uploaded to upper DCS system.
6. Data Archiving & Cyclic Operation: Full-process parameters and action sequence of each synchronization operation are saved automatically before the unit resumes cyclic sampling for next grid connection task.

V. Application Scenarios

(1) Main Thermal Power Units (Coal/Gas-fired)

Terminal grid connection of turbo-generators and automatic bus transfer of station service transformers, matched with large-scale UNITROL6000 excitation system to realize full-automatic precise synchronization for main units.

(2) Hydropower Plant Hydro-generator Units

(3) Cogeneration Captive Power Plants for Chemical & Steel Industry

Grid connection of waste heat power generating units and paralleling of sectional bus tie breakers inside factory, applicable to harsh sites featuring dense variable-frequency loads and severe grid harmonic distortion.

(4) Substation Bus Tie Paralleling

(5) Spare Part Retrofit for Obsolete Excitation Systems