Bi-Fuel Control Valve

The OptiBlend® system is designed to allow for fuel switching during full or partial load conditions without interruption of engine speed or power. The natural gas is fumigated to the combustion chambers using the stock air intake system. When the diesel fuel is injected into the chamber it acts as a pilot igniting the air-gas mixture. The fuel control valve adjusts the air-to-natural gas ratio based on the engine load. The gas train feeds the mixer(s) via an infinitely adjustable throttle valve (butterfly-style) giving better control over the system.

The fuel control valve has internal software with fault detection and position control. The position is managed by the PLC and is mapped relative to load during commissioning. A 5-point load vs. throttle position curve is generated and stored to the programmable logic controller (PLC). The fuel control valve is optimized to allow the best fuel-to-air ratio for each operating point. At loads between those points the PLC interpolates the throttle position.

The PLC has several alarm thresholds which need to be set during commissioning. It is helpful to record sensor values while commissioning so they can be easily compared to different engine loads with and without the addition of gas.