Control apparatus for internal combustion engine with supercharger and method for controlling internal combustion engine with supercharger

A control apparatus for an internal combustion engine with a supercharger, comprising:

• a boost-pressure detector to detect a boost pressure controlled by the supercharger;
• calculating circuitry configured to calculate, in accordance with an operation state of the internal combustion engine, a steady-state target boost pressure in a steady operation state of the internal combustion engine;
• first boost pressure control circuitry configured to perform first boost pressure control with a feedback control algorithm to control the supercharger such that the boost pressure reaches a target pressure if the boost pressure is lower than the steady-state target boost pressure;
• target pressure setting circuitry configured to
• set the target pressure to an initial target pressure lower than the steady-state target boost pressure when the first boost pressure control starts,
• gradually increase the target pressure from the initial target pressure at a first rate if the target pressure is set to the initial target pressure and if a difference pressure between the boost pressure detected during execution of the first boost pressure control and the initial target pressure is equal to or less than a difference threshold pressure, and
• gradually increase the target pressure to the steady-state target boost pressure from the initial target pressure at a second rate smaller than the first rate if the boost pressure detected during execution of the first boost pressure control is equal to or higher than a threshold pressure while the target pressure is increased gradually at the first rate;
• second boost pressure control circuitry configured to perform second boost pressure control with the feedback control algorithm to control the supercharger such that the boost pressure reaches the steady-state target boost pressure if the boost pressure is lower than the steady-state target boost pressure;
• and
• inhibiting/allowing circuitry configured to inhibit execution of the first boost pressure control and allow execution of the second boost pressure control if the boost pressure is lower than the steady-state target boost pressure and if the steady-state target boost pressure is lower than the threshold pressure.

A control apparatus for an internal combustion engine with a supercharger, comprising:

• boost-pressure detecting means for detecting a boost pressure controlled by the supercharger;
• calculating means for calculating, in accordance with an operation state of the internal combustion engine, a steady-state target boost pressure in a steady operation state of the internal combustion engine;
• first boost pressure control means for performing first boost pressure control with a feedback control algorithm to control the supercharger such that the boost pressure reaches a target pressure if the boost pressure is lower than the steady-state target boost pressure;
• initial target pressure setting means for setting the target pressure to an initial target pressure lower than the steady-state target boost pressure when the first boost pressure control starts;
• first gradually increasing means for gradually increasing the target pressure from the initial target pressure at a first rate if the target pressure is set to the initial target pressure and if a difference pressure between the boost pressure detected during execution of the first boost pressure control and the initial target pressure is equal to or less than a difference threshold pressure;
• second gradually increasing means for gradually increasing the target pressure to the steady-state target boost pressure from the initial target pressure at a second rate smaller than the first rate if the boost pressure detected during execution of the first boost pressure control is equal to or higher than a threshold pressure while the target pressure is increased gradually at the first rate;
• second boost pressure control means for performing second boost pressure control with the feedback control algorithm to control the supercharger such that the boost pressure reaches the steady-state target boost pressure if the boost pressure is lower than the steady-state target boost pressure;
• and
• inhibiting/allowing means for inhibiting execution of the first boost pressure control and allowing execution of the second boost pressure control if the boost pressure is lower than the steady-state target boost pressure and if the steady-state target boost pressure is lower than the threshold pressure.

A method for controlling an internal combustion engine with a supercharger, comprising:

• detecting a boost pressure controlled by the supercharger;
• calculating, in accordance with an operation state of the internal combustion engine, a steady-state target boost pressure in a steady operation state of the internal combustion engine;
• performing first boost pressure control with a feedback control algorithm to control the supercharger such that the boost pressure reaches a target pressure if the boost pressure is lower than the steady-state target boost pressure;
• setting the target pressure to an initial target pressure lower than the steady-state target boost pressure when the first boost pressure control starts;
• gradually increasing the target pressure from the initial target pressure at a first rate if the target pressure is set to the initial target pressure and if a difference pressure between the boost pressure detected during execution of the first boost pressure control and the initial target pressure is equal to or less than a difference threshold pressure;
• gradually increasing the target pressure to the steady-state target boost pressure from the initial target pressure at a second rate smaller than the first rate if the boost pressure detected during execution of the first boost pressure control is equal to or higher than a threshold pressure while the target pressure is increased gradually at the first rate;
• performing second boost pressure control with the feedback control algorithm to control the supercharger such that the boost pressure reaches the steady-state target boost pressure if the boost pressure is lower than the steady-state target boost pressure;
• and
• inhibiting execution of the first boost pressure control and allowing execution of the second boost pressure control if the boost pressure is lower than the steady-state target boost pressure and if the steady-state target boost pressure is lower than the threshold pressure.