| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To effectively utilize the performance of a turbocharger by avoiding excessive suppression of supercharging pressure while preventing oil coking in a diffuser part of a compressor. <P>SOLUTION: A turbocharger 30 is equipped with a turbine 32 provided to an exhaust passage 20 in an internal combustion engine, a compressor 34 provided to an intake passage 22 in the internal combustion engine and a rotation speed changing means for changing rotation speed of the compressor 34 by changing flow rate or flow velocity of exhaust gas passing through the turbine 32. An ECU 70 is equipped with a basic target supercharging pressure setting means for setting basic target supercharging pressure on the basis of an operating state of the internal combustion engine, a maximum target supercharging pressure setting means for setting maximum target supercharging pressure which is an upper limit value of supercharging pressure on the basis of an engine rotation speed and a target supercharging pressure setting means at oil deterioration for setting target supercharging pressure at oil deterioration on the basis of an oil coking producing condition due to oil deterioration. The minimum value of target supercharging pressure is taken as the final target supercharging pressure. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
