Patent ID: 7316220

Claim:
A fuel injection system of an internal combustion engine, the fuel injection system comprising: a charge circuit for storing electrical energy; an injector having an actuator, which is driven by the electrical energy stored in the charge circuit, and a valve member, which is driven to open or to close by the actuator directly or indirectly, wherein the injector injects high-pressure fuel by opening and closing the valve member; and a control device for calculating target injection timing corresponding to an operating state of the engine and command injection timing for starting the injection at the target injection timing, and for making the injector inject the fuel at the target injection timing by supplying the electrical energy from the charge circuit to the actuator at the command injection timing, wherein the control device includes timing correcting means for monitoring the electrical energy stored in the charge circuit immediately before the command injection timing and for estimating the electrical energy at the command injection timing based on the monitored value of the electrical energy, the timing correcting means correcting the command injection timing based on the estimated electrical energy so that the injector injects the fuel at the target injection timing.