Heavy-Duty Engine Intake Manifold Pressure Virtual Sensor 2019-01-1170

Increasing demands for more efficient engines and stricter legislations on exhaust emissions require more accurate control of the engine operating parameters. Engine control is based on sensors monitoring the condition of the engine. Numerous sensors, in a complex control context, increase the complexity, the fragility and the cost of the system. An alternative to physical sensors are virtual sensors, observers used to monitor parameters of the engine thus reducing both the fragility and the production cost but with a slight increase of the complexity. In the current paper a virtual intake manifold cylinder port pressure sensor is presented. The virtual sensor is based on a compressible flow model and on the pressure signal of the intake manifold pressure sensor. It uses the linearized pressure coefficient approach to keep vital performance behaviors while still conserving calibration effort and embedded system memory. The virtual sensor approach is evaluated from the perspectives of accuracy and robustness. The design and evaluation of the virtual sensor are based on a heavy-duty diesel engine experiment series. The virtual sensor provides promising results indicating its future use in real-time intake manifold cylinder port pressure estimation.