CONTROL METHOD OF AIR-FUEL MIXTURE COMPOSITION FOR INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To improve the accuracy of control in a device of performing adjustment of actual control value and average value of periodical vibration in control operation variable by the change of a delay time. by obtaining an unnecessary time for control from a control operation variable characteristic, and considering the unnecessary time for control when changing the delay time. SOLUTION: To a controller 2, a signal of operation parameter of an internal combustion engine, namely each output signal of load measurement means 6, rotation speed sensor 7 and exhaust gas sensor 8 is input, and according to these signals. the supply quantity of fuel from a fuel supply quantity measurer 9 is calculated. In this case, a signal of the sensor 8 to output change in air-fuel mixture composition as a signal only for an unnecessary time is compared with a target value from a target value characteristic curve group block, in a comparison step, and according to the difference a control operation variable is formed. Then, the control operation variable is multiplied by a standard fuel supply quantity signal obtained from a characteristic curve group block. Accordingly a fuel supply quantity signal ti is formed.