Patent ID: 7877192

Claim:
An apparatus for suppressing variations in the output between cylinders of an internal-combustion engine, the apparatus comprising a control unit configured to: detect a rotational speed parameter in accordance with a rotational speed of the engine; calculate a reference value of the rotational speed parameter; calculate as a relative speed parameter, for each cylinder, an error between the reference value and the rotational speed parameter detected every predetermined crank angle; integrate, for each cylinder, the relative speed parameter over a predetermined period to calculate an integrated value; calculate a first average value that is an average per cylinder of the sum of the integrated values of all of the cylinders; calculate, for each cylinder, an error between the integrated value of the cylinder and the first average value; and control, for each cylinder, the output of the engine in accordance with the error between the integrated value of the cylinder and the first average value calculated for the cylinder such that variations in the output between the cylinders are suppressed.