Air-Fuel Ratio (AFR) Controls

Air-fuel ratio (AFR) controls work in conjunction with catalysts to control and monitor the mass ratio of air to fuel in an internal combustion engine. At Alberta Governor, we carry the following AFR controls:

Woodward E3 Rich Burn Control

E3 Rich Burn integrates fuel control and catalyst control in a single system using StableSense™ Technology. Unlike first-generation A/F controls, E3 Rich Burn effectively analyzes, controls and optimizes engine and catalyst functions without continuous readjustment.

The system can be used as a stand-alone air-fuel ratio controller or as a complete gas engine emissions and engine control. It is designed for stoichiometric, spark-ignited natural-gas engines used in gas compression, power generation, pumping, and other stationary applications ranging from under 300 kW (400 hp) to over 2 MW (2700 hp). It has full authority over spark, fuel, and air. Additionally, diagnostics such as misfire detection and other health monitoring and engine protection functions are integrated into the system.

The E3 Rich Burn system-based solution analyzes and controls all of the functions of your engine and catalyst to optimize the amount of time your engine is in compliance. The system controls the air-fuel ratio through a fuel metering trim valve. By means of the exclusive StableSense™ oxygen feedback sensor in the exhaust and the unique StableSense™ control algorithm the air-fuel ratio (lambda) is controlled slightly below 1 to optimize the three-way catalyst emission reduction.

Features include:

  • Greatly reduced out-of-compliance downtime
  • Exclusive StableSense technology
  • Engine and catalyst health monitoring and alarming
  • Consistent engine starting over a wide range of conditions
  • Integrated engine protection and diagnostics to ensure safe engine operation
  • Works with both single- and dual-bank engines
  • Improved engine performance with automatic on-line cylinder bank balancing on dual-bank engines
  • Integrated approach improves reliability and reduces overall cost
  • Scalable to meet the entire range of customer needs
  • Supports RS-485 serial Modbus slave multi-drop communications up to 115 kBaud

Woodward E3 Lean Burn Full Authority Fuel Blending Control

Woodward’s E3 Lean-Burn Trim system controls lean-burn industrial gas engines used in numerous power generation, pumping, and other stationary applications. The highly accurate, closed-loop control system helps customers meet regulated emission levels while maintaining engine performance over a wide range of fuel qualities.

The E3 Lean-Burn’s core functionality is an air/fuel ratio trim control using either exhaust oxygen closed loop or generator power feedback. The system can control speed/load, air/fuel ratio and spark timing/duration, at any engine load and speed condition.

Features include:

  • Woodward Stable Sense Oxygen Sensors, designed for natural gas engines
  • Integrated approach reduces system complexity and reduces overall cost
  • Speed-density-based Air Fuel Ratio controller
  • Flexible Programming
  • Four different blending modes:
    • External blend ration with load shedding
    • Internal blend ratio with constant power
    • Pipeline gas avoidance with load shedding
    • Knock abatement with load shedding

Woodward TecJet with E3 Fuel Blending System

The E3 Fuel Blending System uses TecJet fuel metering valves for independent, full-authority control of two different fuel streams into a single engine. The system is designed to be able to meter the two fuels in any ratio from 0% to 100%.

Features include:

  • Woodward Stable Sense Oxygen Sensors, designed for natural gas engines
  • Forms ideal combination with any Woodward Full-Authority control
  • Bi-directional communication via CANbus: CAN J1939, CANopen, or custom CAN
  • Integrated sensors and electronics
  • Microprocessor based mass gas flow control
  • Accurate over entire flow range
  • Fast response to flow commands
  • Flow testing ensures that the engine does not have to be recalibrated if TecJet is replaced
  • Compensates for gas pressure and gas temperature fluctuations
  • Requires only analog or digital desired gas flow signal and supply voltage (CAN communication recommended)
  • Can be supported by flanges