Control apparatus, control method and engine control unit

A control method comprising the steps of:

• calculating a deviation of an output of a controlled object from a predetermined target value;
• calculating a first control input to said controlled object for converging the output of said controlled object to said target value in accordance with the calculated deviation based on one modulation algorithm selected from a Δ modulation algorithm, a ΔΣ modulation algorithm, and a ΣΔ modulation algorithm;
• calculating a second control input to said controlled object for converging the output of said controlled object to said target value in accordance with the calculated deviation based on a response specified control algorithm;
• detecting a state of said controlled object;
• selecting one of said first and second control inputs in accordance with the detected state of said controlled object as a control input;
• and
• switching, in response to a change from one of said first and second control inputs to the other one, from said one control input to said other control input when the calculated deviation falls within a predetermined range.

An engine control unit including a control program for causing a computer to calculate a deviation of an output of a controlled object from a predetermined target value;

• calculate a first control input to said controlled object for converging the output of said controlled object to said target value in accordance with the calculated deviation based on one modulation algorithm selected from a Δ modulation algorithm, a ΔΣ modulation algorithm, and a ΣΔ modulation algorithm;
• calculate a second control input to said controlled object for converging the output of said controlled object to said target value in accordance with the calculated deviation based on a response specified control algorithm;
• detect a state of said controlled object;
• select one of said first and second control inputs in accordance with the detected state of said controlled object as a control input;
• and switch, in response to a change from one of said first and second control inputs to the other one, from said one control input to said other control input when the calculated deviation falls within a predetermined range.