| 摘要 |
PURPOSE:To control an air-fuel ratio in an engine test to a specific value in a short time by detecting and feeding the air-fuel ratio back continuously by an input method in the beginning, and then estimating and determining a fuel supply manipulated variable from the last process and controlling the air-fuel ratio by an output method. CONSTITUTION:The air-fuel ratio is calculated by the input method through an AF value computing element 13 on the basis of outputs of a suction air quantity detector 11 and a fuel flow rate detector 12 and compared with a set value by a subtracter 14, and an operation signal is supplied to a pump motor 31 so that the deviation is zero. The approximation of the air-fuel ratio to the set value is timed under this continuous feedback control to detect manipulated variables at plural points of time and air-fuel ratios corresponding to the manipulated variables, and they are stored in a predictive arithmetic device 22. Then, the exhaust gas from an engine 4 is guided to an AF value detector 21 and analyzed to detect an air-fuel value, and the arithmetic device 22 varies an operation signal stepwise and supplies it to the pump motor 31 through a changeover switch 6 to control the air-fuel ratio. |
