Control apparatus for engine

A control apparatus for an engine comprising:

• a rotation detector measuring an engine speed;
• a fuel supply device supplying a fuel into a combustion chamber of the engine based on a command value for a fuel injection amount;
• and
• an output controller setting an allowable range for an output of the engine and controlling the output of the engine within the allowable range, wherein
• the output controller calculates an emission amount of pollutant from the command value for the fuel injection amount for the fuel supply device and the engine speed measured by the rotation detector,
• the output controller calculates an accumulated emission amount of the pollutant emitted from the engine for a period of time from a first point of time to a current point of time,
• the output controller calculates a maximum allowable emission amount of the pollutant for a period of time from the first point of time to a second point of time at which a predetermined period of time has elapsed from the first point of time,
• the output controller calculates a difference between the calculated accumulated emission amount of the pollutant and the calculated maximum allowable emission amount of the pollutant,
• the output controller calculates a first output index by dividing the calculated difference by the period of time from the current point of time to the second point of time, and
• the output controller sets the allowable range for the output of the engine so that the emission amount of the pollutant becomes equal to or less than the first output index.