Woodward 9905-148 | 2301A Series Electronic Load Sharing and Speed Control Module

Description

Product Overview

Key Technical Specifications

• Input Voltage: 10-40 Vdc (nominal 24 Vdc) – compatible with global industrial power systems.
• 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 (varies by source; typical: ~280 mm × 210 mm × 90 mm) – fits standard industrial cabinets.
• Weight: ~4.0 kg (8.8 lbs) – lightweight for easy handling during maintenance.

  

  Woodward 9905-001-L

Field Application & Problem Solved

• Grid frequency deviations (triggering penalties or equipment shutdowns).
• Overload of individual generators (reducing lifespan).
• Inefficient energy transfer (increasing fuel consumption).

1. Precision Speed Regulation:
   The module uses phase-locked loop (PLL) algorithms​ to maintain speed within ±0.1% of the setpoint (isochronous mode). This stability is critical for power plants, where frequency deviations of ±0.5 Hz can trigger grid penalties.
2. Automatic Load Sharing:
   In parallel operation (droop mode), the 9905-148 distributes load evenly across generators (±1% accuracy). For example, a marine vessel using multiple generators with the 9905-148 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: Controlling steam turbines/gas turbines in coal-fired/gas-fired power plants to maintain grid frequency stability.
• Marine Propulsion: Controlling shipboard turbines/engines 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 (10-40 Vdc) 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 9905-148. Incorrect sensor calibration can lead to speed deviations—verify with a multimeter.
3. Test Load Sharing Logic:
   • After installation, test the load sharing logic using a resistive load bank. Verify that the 9905-148 distributes load evenly across generators (±1% accuracy)—this step prevents issues like “one generator taking all the load” during operation.
4. Perform Regular Maintenance:
   • Inspect the 9905-148 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 9905-001-L

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.
   • Operator inputs​ (via front-panel potentiometers) for speed setpoint and droop adjustment.
2. Processing & Control:
   The analog circuitry processes the input signals using PID (Proportional-Integral-Derivative)​ algorithms to calculate the required fuel/steam flow. The isochronous mode maintains constant speed by adjusting the actuator output, while the droop mode adjusts speed based on load.
3. 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.
4. Communication & Monitoring:
   The 9905-148 is compatible with Woodward’s SPM-A synchronizers and other power generation controls, allowing for seamless integration with plant DCS/SCADA systems. Operators can use Woodward’s 2301A Explorer​ software to visualize trends, adjust setpoints, and perform diagnostics remotely.

Final Notes