Patent ID: 7047740

Claim:
A boost pressure estimation apparatus for an internal combustion engine with a super charger and a waste gate valve, the supercharger using an exhaust pressure to drive an exhaust turbine provided for an exhaust pipe of an internal combustion engine and to drive a compressor provided for an intake pipe to supply air into a cylinder, the waste gate valve opening and/or closing an exhaust bypass pipe to bypass the exhaust turbine, the boost pressure estimation apparatus comprising: a means for detecting intake air amount for detecting an intake air amount of an internal combustion engine; a turbine-supplied gas amount calculation means for calculating an exhaust gas amount supplied to the exhaust turbine (hereafter referred to as a “turbine-supplied gas amount”) based on an intake air amount detected by the means for detecting intake air amount and opening of the waste gate valve; and a boost pressure estimation means for calculating an estimated value of the supercharger boost pressure (hereafter referred to as an “estimated boost pressure”) based on the turbine-supplied gas amount.