Patent ID: 6644029
Filing Date: 2003-11-11
Classification: F02B,Y02T

Abstract:
A process for controlling a boost pressure limitation of a turbocharger in an internal combustion engine as a function of the density of ambient air, comprising the steps of:determining actual values of the ambient temperature (Tâˆž), the ambient pressure (Pâˆž), and a value of an air mass (mL) drawn in; determining values of a boost pressure (PList) at downstream of a compressor in an operating condition at assigned time intervals; determining actual values of a pressure (PVE) at a compressor intake and a temperature (TVE) at the compressor intake by way of an air mass predetermined value dependent on correction curves; adjusting an air mass throughput (mLkor) at the compressor intake to standard conditions from the pressure (PVE) determined at the compressor intake, from the temperature (TVE) determined at the compressor intake, and from the determined air mass (mL) drawn in, respectively; comparing a maximum permissible compressor speed dependent on an adjusted maximum permissible boost pressure (PLmaxkor), taken respectively from a compressor characteristics being a maximum compressor speed (nVmax) for adjusting the permissible air mass throughput (mLkor) to standard compressor conditions at the compressor intake and the ambient pressure determined (Pâˆž), to the boost pressure (PList) determined in an operating condition; and controlling the boost pressure (PList) so that a maximum value in each instance determined for the boost pressure (PList) corresponds to the adjusted maximum permissible compressor speed dependent boost pressure (PLmaxkor) determined in this state.