Patent ID: 6725660
Filing Date: 2004-04-27
Classification: F02B,F02D,F02M,Y02T

Abstract:
A control device for a variable-geometry turbocharger in an engine having nozzle opening adjustment means for adjusting an opening of the nozzle in a turbine inlet, comprising:detection means for detecting rotational speed and load of said engine, and pressure on at least a compressor outlet side of said variable geometry turbocharger; basic opening target value calculating means for calculating a basic opening target value of said nozzle on the basis of the detected values of the rotational speed and load of said engine; load variation amount calculating means for calculating an amount of variation in the engine load per predetermined time on the basis of the detected value of said engine load; pressure ratio calculating means for calculating a pressure ratio between the compressor outlet and inlet sides on the basis of the detected value of at least the pressure on said compressor outlet side; correction gain calculating means for calculating a correction gain value on the basis of the detected value of said engine rotational speed and said pressure ratio; corrected load variation amount calculating means for calculating an amount of variation in the load following correction on the basis of said correction gain and said engine load variation amount; nozzle opening correction value calculating means for calculating a nozzle opening correction value on the basis of said amount of variation in the load following correction; final opening target value calculating means for calculating a final opening target value of said nozzle on the basis of said basic opening target value and said nozzle opening correction value; and operating means for operating said nozzle opening adjustment means so that the actual opening value of said nozzle is an opening value that corresponds to said final opening target value.