Control System for Internal Combustion Engine

A control system for an internal combustion engine having fuel injection means for injecting fuel into a combustion chamber, said control system comprising:

• cylinder pressure detecting means for detecting a pressure in the combustion chamber;
• heat release amount calculating means for calculating a heat release amount in a predetermined crank angle range according to a pressure detected by said cylinder pressure detecting means;
• and
• fuel injection control means for performing a main injection and a plurality of pilot injections before the main injection by said fuel injection means,
• wherein said fuel injection control means controls a fuel injection amount in a first-performed pilot injection of the plurality of pilot injections according to the heat release amount calculated by said heat release amount calculating means.

A control method for an internal combustion engine having at least one fuel injection valve for injecting fuel into a combustion chamber of said engine, the control method comprising the steps of:

• a) estimating a compression end temperature in the combustion chamber;
• b) setting a target compression end temperature according to an operating condition of said engine;
• and
• c) performing a main injection and a plurality of pilot injections before the main injection by said at least one fuel injection valve,
• wherein a fuel injection amount in a first-performed pilot injection of the plurality of pilot injections is controlled to coincide the estimated compression end temperature with the target compression end temperature.

A control method for an internal combustion engine having at least one fuel injection valve for injecting fuel into a combustion chamber, said control method comprising the steps of:

• a) detecting a pressure in the combustion chamber;
• b) calculating a heat release amount in a predetermined crank angular range according to the detected pressure;
• and
• c) performing a main injection and a plurality of pilot injections before the main injection by said at least one fuel injection valve,
• wherein a fuel injection amount in a first-performed pilot injection of the plurality of pilot injections is controlled according to the heat release amount.