Fuel injection control device for internal combustion engine

A fuel injection control device applied to a fuel injection system for an internal combustion engine, wherein:

• the fuel injection system includes:
• a pressure accumulation chamber capable of accumulating pressure of fuel in a high-pressure state;
• a fuel injection valve injecting fuel, which is supplied by the pressure accumulation chamber, directly into a combustion chamber of the engine;
• a fuel pump highly-pressurizing fuel, which is supplied from a low-pressure side of the system, and supplying the highly-pressurized fuel to the pressure accumulation chamber;
• and
• a fuel pressure detecting means for detecting fuel pressure in the pressure accumulation chamber;
• and
• alcohol-containing fuel including alcohol is employable for fuel in the engine, the fuel injection control device comprising:
• a fuel injection control means for controlling a fuel injection amount of the fuel injection valve;
• and
• a pump control means for calculating a pump control amount based on a feedforward term and a feedback term and for controlling the fuel pump based on the pump control amount, wherein:
• the feedforward term is calculated based on the fuel injection amount of the fuel injection valve;
• the feedback term is calculated based on a difference between a target fuel pressure and an actual fuel pressure, which is detected by the fuel pressure detecting means;
• the fuel injection control means includes a first injection control means for performing the injection of fuel by the fuel injection valve at a starting injection amount in a starting period after commencement of starting of the engine by its starting means until a predetermined rotation increase of the engine is produced in association with fuel combustion;
• the starting injection amount is set based on an alcohol concentration of fuel and a temperature of the engine;
• and
• the pump control means includes a starting control means for calculating the feedforward term based on the starting injection amount in the starting period and for calculating the pump control amount by use of the feedforward term calculated by the starting control means.