Mtu Friedrichshafen Gmbh

Joerg Remele

Andreas Flohr

Andreas Schneider

Albrecht Debelak

Alexander Bernhard

Michael Prothmann

Otto Loehlein

Martin Fritzsche

Martin Lehmann

Andreas Krammer

In a method for controlling the NOx concentration in the exhaust gas of an internal combustion engine in which an NOx control deviation is calculated from an actual NOx value and a desired NOx value, a control value is calculated based on the NOx control deviation via an NOx controller and by means of the control value at least one condition of the cylinder inlet flow volume of the internal combustion engine is adjusted in that, additionally, an adaption injection begin is determined in dependence on the control value of the NOx controller, and the injection begin is changed by the adaption injection begin.

Method for controlling the nox concentration in the exhaust gas of an internal combustion engine

Contributions of individual cylinders of the internal-combustion engine to the rotational acceleration are determined by the rotational speed course of the crankshaft by individually cutting off the cylinders successively. From the thus obtained rotational speed course curves, a pulse response spectrum {right arrow over (I)} of an operating cycle is formed at least for the harmonic of the 0.5th order. In normal operation, the rotational speed course of the crankshaft is then continuously recorded above the angle of each operating cycle. By a Fourier transformation, Fourier coefficients are determined as a resultant {right arrow over (R)} at least of the harmonic of the 0.5th order. Correction factors for the injection quantities are obtained for equalization of the individual cylinders with respect to their rotational speed fractions. The components of the resultant {right arrow over (R)} situated in the direction of the pulse response vectors are multiplied with the pulse responses {right arrow over (I)} and are combined by addition.

Regulation of true running for diesel engines

A novel method and a suitable device for the cylinder-specific determination of spark failures on a reciprocating engine through a classifying unit based on measurement data that contain information about the number of crankshaft revolutions. For this process, the measurement data are subjected to a pre-processing procedure in the classifying unit and classified through a classification process, wherein within the framework of the pre-processing procedure the data are subjected to a principal axis transformation (HAT). Due to the utilization of this resource-saving method for detecting spark failures on reciprocating engines in accordance with the invention, the processing requirements for once cycle are less than 5 Kflops, despite a measurement vector v length of 240. Due to the fact that the invented device requires only a single measurement data recorder, e.g. in the form of a simple gear ring that is attached to the crankshaft and coupled to a motion sensor, even the mechanical design can be produced inexpensively and it can be decoupled from thermal or other negative influences of the environment in a simple manner.

Method and apparatus for detecting spark failure based on the number of crankshaft revolutions

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Hagnau, Germany

Joerg Remele