Woodward 9905-799 | Digital Synchronizer and Load Control Module for Industrial Power Systems

Description

Product Overview

Key Technical Specifications

• Input Voltage:
  • Power supply: 18–40 V DC (nominal 24 V DC) – compatible with global industrial power systems.
  • Generator potential transformers: 120/240 V AC – supports both European (230 V AC) and North American (120 V AC) power standards.
• Output Signals:
  • Voltage bias output: ±9 V DC – for driving external devices or indicating synchronization status.
  • Discrete outputs: Sink up to 200 mA DC – for alarm indication (e.g., synchronization failure, overvoltage).
• Control Modes:
  • Isochronous Mode: Maintains constant prime mover speed (±0.1% tolerance) for standalone or isolated bus operation.
  • Droop Mode: Adjusts speed based on load (adjustable droop percentage) for parallel operation with other generators.
• Actuator Compatibility: Works with Woodward proportional actuators (e.g., EG-3P) for fuel/steam valve positioning.
• Operating Temperature: -40°C to +85°C (-40°F to +185°F) – suitable for extreme industrial environments (e.g., power plants, marine vessels).
• Certifications: CE, UL, CSA – compliant with international industrial safety standards.
• Dimensions: Compact form factor (typical: ~280 mm × 210 mm × 90 mm) – fits standard industrial cabinets.
• Weight: ~3.1 kg (6.8 lbs) – lightweight for easy handling during maintenance.

  

  Woodward 9905-090

Field Application & Problem Solved

• Electrical faults (e.g., short circuits, equipment damage).
• Grid penalties (e.g., fines for frequency deviations).
• Downtime (e.g., generator tripping, process interruptions).

1. Precision Synchronization:
   It uses phase-locked loop (PLL) algorithms​ to match the offline generator’s frequency and phase with the online system (e.g., utility grid) within ±0.1 Hz and ±10° phase difference, respectively. This ensures compliance with grid requirements and prevents phase mismatch faults.
2. Automatic Load Sharing:
   In parallel operation (droop mode), the 9905-799 distributes load evenly across generators (±1% accuracy). For example, a marine vessel using multiple generators with the 9905-799 reduced generator maintenance costs by 20% due to balanced load distribution.
3. Flexible Mode Switching:
   The module supports isochronous​ (constant speed) and droop​ (load-dependent speed) modes, allowing it to adapt to different operational requirements (e.g., standalone backup power vs. parallel grid-connected operation).

• Power Generation: Synchronizing standby generators to the utility grid during peak demand or outages.
• Marine Propulsion: Synchronizing shipboard generators for auxiliary power generation with load sharing.
• Industrial Cogeneration: Balancing electrical load and thermal steam demand in industrial facilities (e.g., paper mills, refineries).

Installation & Maintenance Pitfalls (Expert Tips)

1. Verify Power Supply Compatibility:
   • Confirm that the input voltage (18–40 V DC) matches the module’s rating. Mismatched voltage can damage the internal circuitry—use a multimeter to check the input voltage before installation.
2. Calibrate Speed Sensors:
   • Use a precision tachometer to calibrate the prime mover’s speed sensor (e.g., magnetic pickup) before installing the 9905-799. Incorrect sensor calibration can lead to speed deviations—verify with a multimeter.
3. Test Synchronization Logic:
   • After installation, test the synchronization logic using a signal generator to simulate frequency/phase changes. Verify that the module correctly adjusts the generator’s speed and sends a synchronization signal when the conditions are met.
4. Perform Regular Maintenance:
   • Inspect the 9905-799 annually for signs of wear (e.g., cracked casings, loose connections). Clean the module’s connectors with isopropyl alcohol to remove dirt and debris, which can cause communication failures.

     

     Woodward 9905-090

Technical Deep Dive & Overview

1. Signal Reception:
   The module receives input signals from:
   • Speed sensor​ (magnetic pickup) monitoring prime mover shaft rotation.
   • Load sensor​ (current transformer) measuring generator output current.
   • Generator potential transformer​ (120/240 V AC) measuring grid voltage.
2. Processing & Control:
   The analog circuitry processes the input signals using PID (Proportional-Integral-Derivative)​ algorithms to calculate the required speed and load adjustments. The isochronous mode maintains constant speed by adjusting the actuator output, while the droop mode adjusts speed based on load.
3. Synchronization:
   The module uses a phase comparator​ to align the generator’s phase with the online system’s phase. Once synchronized, it sends a contact closure signal to close the circuit breaker, enabling parallel operation.
4. Output & Actuation:
   The module sends a control signal to the prime mover’s actuator (e.g., fuel valve) to adjust the fuel/steam flow, thereby regulating speed and load. Simultaneously, it monitors for fault conditions (e.g., overspeed, low oil pressure) and triggers alarms if necessary.

Final Notes