Patent ID: 7219003

Claim:
A method for controlling, in closed loop fashion, the operation of an internal combustion engine including engine cylinders, said method comprising the following steps: a) sampling an engine speed signal, b) applying a Hartley-transformation to said engine speed signal for transforming said engine speed signal into an angular frequency range, c) analyzing said angular frequency range for producing individual angular frequency orders representing phase information and amplitude information, d) performing a cylinder classification based on said phase information and said amplitude information by first comparing said phase information with a given reference phase value and by second comparing said amplitude information with a given first amplitude threshold value, said first comparing and said second comparing yielding individual cylinder informations for each cylinder of said engine cylinders, e) processing said individual cylinder informations for identifying, based on said first phase comparing, any cylinder which is causing an uneven running of said internal combustion engine for further identifying, also based on said first phase comparing, a fuel adjustment direction for each individual cylinder including said cylinder causing said uneven running, and for determining, based on said second amplitude comparing, an injection fuel quantity required for correcting said uneven running of said internal combustion engine, f) generating in response to said processing a closed loop control signal and applying said closed loop control signal to an engine controller for correcting said uneven running of said internal combustion engine, g) detecting a misfiring of any one of said engine cylinders by further comparing said amplitude information with a respective second given amplitude threshold value to provide information for concluding whether said uneven running is caused by said misfiring when said amplitude information exceeds said respective second given amplitude threshold value, h) detecting an actual power output of said internal combustion engine, i) comparing said actual power output with a rated power output of said internal combustion engine to provide a reduced power output information, j) modifying said closed loop control signal in response to said reduced power output information, and k) applying said modified closed loop control signal to said engine controller for controlling a fuel injection to all said engine cylinders for correcting said actual power output with reference to said rated power output.