PURPOSE: To make actual igniton time coincident with commanded ignition time and attain always optimal torque, by effecting ignition at compensated ignition time which is set by adding to the commanded ignition time a rotative fluctuation compensation angle for compensating the fluctuation in one rotation of a crankshaft.
CONSTITUTION: In a step 10, a revolution speed signal from a rotation sensor 1a and signals from a sucked air pressure sensor 1b, a water temperature sensor 1c, a sucked air temperature sensor 1d, an acceleration and deceleration sensor 1e and an EGR sensor 1f are applied as inputs. In a step 11, commanded ignition time ΘPO is determined from these control signals. In a step 12, a rotative fluctuation compensation angle ΘHO is added to the commanded ignition time ΘPO to calculate compensated ignition time ΘTO=ΘPO+ΘHO. In a step 13, ignition time T0 is predicted from the compensated ignition time and revolution speed. Signal input time to is stored in a calculation circuit 2. After the time T0 has elapsed since the time t0, an ignition instruction is applied and the time t1 of the application is stored in a step 14.
YAMADA TAKU
SHIMAMOTO MAMORU
