Control apparatus and control method for internal combustion engine

A control apparatus for an internal combustion engine, the internal combustion engine including an intake passage, an exhaust passage and an actuator, the control apparatus comprising

• an electronic control unit configured to:
• output a command signal to the actuator and control a controlled variable of the internal combustion engine;
• acquire an intake pressure in the intake passage;
• acquire an atmospheric pressure;
• calculate a normalized intake pressure, the normalized intake pressure being a pressure obtained by normalizing the intake pressure by the atmospheric pressure;
• calculate a pumping loss torque of the internal combustion engine based on the normalized intake pressure;
• calculate a first value or a value of a linear function in which the first value is an independent variable as the normalized intake pressure, the first value being obtained by dividing the intake pressure by the atmospheric pressure;
• store relational data, the relational data being data that associate an output value normalized by the atmospheric pressure with the normalized intake pressure;
• calculate the output value based on the normalized intake pressure and the relational data,
• the output value being one of a second value obtained by dividing the pumping loss torque by the atmospheric pressure, a normalized pumping loss torque as a value of a linear function in which the second value is an independent variable, a third value obtained by dividing an exhaust pressure as a pressure in the exhaust passage by the atmospheric pressure, and a normalized exhaust pressure as a value of a linear function in which the third value is an independent variable;
• and
• calculate one of the pumping loss torque based on the normalized pumping loss torque and the atmospheric pressure, and the exhaust pressure based on the normalized exhaust pressure and the atmospheric pressure, the exhaust pressure being utilized to calculate the pumping loss torque based on a differential pressure from the intake pressure.