Description

WOODWARD 9907-135

I. Basic Information

Model: 9907-135

Series: Woodward GS3/LQ High Current Valve Driver Module

Brand: USA

Product Type: High-precision servo drive controller for electro-hydraulic fuel valves

Compatible Equipment: LQ3, LQ25, LQ25T and LQ bypass series actuators, widely used in gas turbines, steam turbines and generator sets. It converts 4~20mA valve position commands from turbine governors into high-current driving output, and realizes closed-loop precise valve control via resolver position feedback.

Product Positioning

The 9907-135 serves as the core power driving component of turbine speed control systems. It converts weak analog control signals into high-power output to drive heavy-duty fuel regulating valves, adopts resolver closed-loop feedback to ensure valve position follows set commands accurately, effectively preventing unit speed fluctuation, load instability and overspeed tripping faults caused by fuel regulation deviation. Equipped with multi-level hardware protection against overcurrent, overvoltage, short circuit and reverse wiring, it supports long-term heavy-duty continuous operation in power, petrochemical and metallurgical industries, widely used in equipment overhaul spare part replacement and control system technical renovation projects.

Hardware Architecture

Isolated 4~20mA Command Acquisition Unit: Opto-isolated input circuit suppresses ground loop and harmonic interference from on-site frequency converters, equipped with hardware signal filtering to avoid valve misoperation caused by signal drift.
Resolver Closed-loop Feedback Processing Unit: Dedicated resolver decoding circuit collects real-time valve opening value, forms PID closed-loop regulation with given command, and achieves steady-state control accuracy up to ±0.1%FS.
High-power Amplifier Drive Unit: Industrial power devices provide maximum 24A output current, with built-in current limiting function to protect actuator coils from burnout caused by valve jamming overcurrent.
Hardware Fault Diagnosis & Indication Unit: Multi-channel LED status indicators display power supply, command input, feedback abnormality and drive fault; fault status is latched and can be uploaded to the upper governor for rapid troubleshooting.
Aluminum Alloy DIN Rail Mounting Unit: Sealed heat-dissipating aluminum housing with fin structure ensures efficient heat dissipation under continuous high-load operation, suitable for compact cabinet installation.

Mounting Specifications

Power Supply: DC 10~32V, rated 24VDC
Control Input: 4~20mA, accuracy ±0.05%FS
Max Output Current: 24A
Feedback Type: Single-channel resolver
Response Time: ≤1ms
Mounting: 35mm standard DIN rail snap installation
Dimension: 292mm×175mm×68mm
Net Weight: 1.2kg
Protection Class: IP20 (indoor cabinet)
Supporting Equipment: Woodward 505/2301 governor, LQ series electro-hydraulic actuator, resolver, 24VDC redundant power supply, shielded signal cable
Commissioning Tools: Woodward ProView software, 4~20mA signal generator, multimeter, anti-static wristband

Supporting System

Supporting Hardware

Gas/steam turbine generator units, Woodward speed governors, fuel actuators, resolver sensors, DC control power supply, quick fuses.

Commissioning Tools

ProView configuration software, process signal calibrator, insulation tester, clamp ammeter.

Upper-level System

Unit DCS and plant SCADA system collect valve position feedback and module fault alarm signals via the governor to realize remote equipment monitoring.

Typical Application Industries

Thermal power self-provided power plants, petrochemical compressor stations, metallurgical waste heat power stations, marine power units, industrial waste incineration power generation facilities.

Product Features

High-current Heavy-load Driving Capacity: 24A maximum output adapts to high-torque industrial fuel actuators, eliminating regulation lag and frequent overcurrent protection faults of ordinary low-power drive modules.
High-reliability Resolver Closed-loop Control: Resolver feedback is resistant to high temperature, vibration and oil pollution, avoiding potentiometer wear failures that lead to speed control oscillation and load fluctuation.
Three-way Galvanic Isolation Anti-interference Design: Isolation for command, feedback and drive circuits prevents electromagnetic interference from causing valve runaway and unit overspeed safety accidents.
Comprehensive Hardware Safety Protection: Five built-in protection mechanisms including short circuit, overcurrent, reverse power and feedback disconnection instantly cut off drive output and latch fault status to protect actuators and main control systems.
Wide-temperature Industrial Rugged Design: Operating range from -40℃ to +85℃, compliant with IEC EMC standards, 24/7 continuous stable operation with MTBF ≥180000 hours.
Plug-and-play Compatible Replacement: Fully matched with GS3/LQ series actuators, existing wiring and governor parameters can be reused to minimize unit downtime during maintenance.

II. Technical Specifications

2.1 Electrical Parameters

Model: 9907-135
Power Range: DC 10~32V, rated 24VDC
Analog Input: 4~20mA, accuracy ±0.05%FS
Maximum Drive Current: 24A with hardware current limiting
Feedback Interface: Dedicated resolver decoding channel
Response Time: ≤1ms
Dielectric Withstand Voltage: 1500VAC/1min for signal isolation channels
Protection Functions: Short-circuit, overcurrent, reverse polarity, overvoltage, feedback break fault latch protection
Control Mode: PID closed-loop valve regulation, forward/reverse action configurable via software

2.2 Mechanical Parameters

Mounting: Vertical snap installation on 35mm DIN rail
Housing: Die-cast aluminum alloy heat dissipation shell
Terminals: Spring anti-loose terminals for 0.75~4mm² shielded cables
Indicators: Four LED lights for power, input, feedback and fault status
Dimension: 292×175×68mm
Net Weight: 1.2kg

2.3 Environmental Specifications

Operating Temperature: -40℃ ~ +85℃
Storage Temperature: -45℃ ~ +90℃
Humidity: 5%~95%RH, non-condensing, no corrosive gas or conductive dust

III. Key Features

Closed-loop Servo Amplification for Fuel Valve Position Control: Converts governor analog commands into high-current drive signals, stabilizes unit rotating speed and output load through resolver PID closed-loop regulation.
Heavy-duty Electro-hydraulic Actuator High-power Drive: Sufficient current margin copes with extreme working conditions such as valve jamming and low-temperature viscous hydraulic oil to guarantee fast speed regulation response.
Real-time Fault Diagnosis for Actuator and Wiring Loops: Detects feedback disconnection, coil overload and short-circuit faults, triggers safety interlock to prevent unit overspeed accidents.
Flexible Software Parameter Configuration: PID gain, control action direction, stroke limit and filter time can be modified online to adapt to different LQ series actuators without hardware modification.
Hierarchical Safety Isolation for Speed Control Systems: Prevents secondary damage to the main governor caused by valve-side electrical faults, improving the overall reliability of the turbine control system.
Legacy Turbine Control System Spare Part & Retrofit Component: Suitable for aging drive module replacement and actuator upgrade transformation of old generating units to maximize existing automation resource reuse.

IV. Working Principle

After power-on self-test of power supply, signal acquisition, feedback and drive circuits, the module enters closed-loop standby mode. It receives 4~20mA valve position setpoint from the Woodward governor, collects real-time valve opening via resolver, calculates deviation through PID algorithm, and outputs amplified current to drive the electro-hydraulic actuator until the actual valve position matches the set value. Once faults such as short circuit, overcurrent or feedback disconnection are detected, the drive output is immediately blocked with fault status latched and uploaded to the governor to trigger unit safety interlock. Normal operation can be restored by power cycling after troubleshooting.

V. Application Scenarios

Speed control system maintenance and technical upgrading for thermal power and self-owned power plant gas/steam turbine units.
Fuel valve servo drive for process turbines and compressors in refinery, chemical and natural gas stations.
Waste heat power generation unit control system renovation in metallurgical and mining enterprises.
Marine diesel and gas turbine generator set speed regulation equipment maintenance.
Medium and small turbine hardware overhaul and compatible transformation for waste incineration and residual heat power plants.