In-Cylinder Pressure Reconstruction for Multicylinder SI-Engine by Combined Processing of Engine Speed and One Cylinder Pressure

Abstract

The paper presents an approach to reconstruct cylinder-individual pressure of each combustion cycle by processing the instantaneous fluctuations of the engine speed and the in-cylinder pressure of one cylinder. A new pressure model with a feasible number of parameters is combined with a model-based torque estimation in order to reconstruct the pressure traces. The performance of the proposed algorithm is demonstrated with measurement data acquired from a vehicle with a four cylinder spark ignition (SI) engine.

Adaptation of a zero-dimensional cylinder pressure model for diesel engines using the crankshaft rotational speed

“…Hamedović proposes the combined processing of one cylinder pressure signal together with the engine speed [1,33]. This approach focuses on the cylinder-individual estimation of torque and combustion phasing especially with respect to the stabilization of partly homogeneous combustion processes.…”

“…Within the present study, a method proposed by Hamedović et al is applied [33,41], which performs a joint evaluation of the engine speed and the cylinder pressure signal. The compensation is carried out using measurements in motored condition and bases on an equalization of the calculated crankshaft energy from cylinder pressure and engine speed.…”

Engine cylinder pressure reconstruction using crank kinematics and recurrently-trained neural networks

“…In addition, certain features required for On Board Diagnostics could also be improved were pressure traces available for misfire detection, and for in-vehicle calibration by using the cylinder pressure trace for torque estimation [3]. Previous approaches using other on-board sensors, include the use of engine block vibration [4][5], crank kinematics [6] [7], and spark ignition ionisation current [8].…”

“…Use of crank speed and position in [ 12], exploited a second-order sliding-mode differentiator to estimate instantaneous indicated torque including friction, and was shown using a Simulink model for a 2 litre I4 gasoline engine, to obtain Pmax within 5%. A model was combined with a single pressure measurement in [7] to reconstruct pressure on the other cylinders of an I4 DISI engine,…”

Towards real-time and memory efficient predictions of valve states in diesel engines

“…Several authors have addressed the usability of in-cylinder pressure in the domain of engine control. At first, research focused on establishing a model for in-cylinder pressure curves in various fields of applications [2], [3], [4]. As pointed out by Sellnau et al [5], it does not only result in primary system benefits like an increased fuel economy or reduced NOx emmisions, but also in secondary effects like air-fuel balancing or calibration assistance.…”