High Accuracy Glow Plug-Integrated Cylinder Pressure Sensor for Closed Loop Engine Control

The PressureSense Glow Plug combines a miniature cylinder pressure sensor with the automotive glow plug. The 1.7mm diameter fiber optic-based sensor is welded into the glow plug heater and the signal conditioner is encapsulated into a “smart connector” located on the top of the glow plug body. The sensor offers accuracy better than +/-2% of reading between 220 bar and 5 bar and +/-0.2 to +/-0.5 bar error for pressures below 5 bar. The performance of “dummy” as well as glowing and pressure sensing devices was evaluated on various engines and over a wide range of engine operating conditions.