Controller for supercharger-equipped internal combustion engine

Patent metadata

Field	Value
Publication number	US-2017051663-A1
Application number	US-201615137199-A
Country	US
Kind code	A1
Filing date	Apr 25, 2016
Priority date	Aug 21, 2015
Publication date	Feb 23, 2017
Grant date	—

Abstract

A controller, for a supercharger-equipped internal combustion engine, that can improve the feedback response of compressor driving force is provided. In a controller, inertial force produced by an inertial moment of a supercharger is calculated, based on a real rotation speed of the supercharger; then, driving force feedback control is implemented in which a gate valve control value, which is a control value for a gate valve actuator, is changed so that an addition value obtained by adding the inertial force to the real compressor driving force approaches a target compressor driving force.

First claim

What is claimed is:

1 . A controller for an internal combustion engine equipped with a supercharger having a turbine provided in an exhaust path, a compressor that is provided at the upstream side of a throttle valve in an intake path and rotates integrally with the turbine, a wastegate valve provided in a bypass, in the exhaust path, that bypasses the turbine, and a gate valve actuator that drives the wastegate valve, the controller for an internal combustion engine equipped with a supercharger comprising:
a driving-condition detector that detects a real rotation speed of the supercharger; a target compressor driving force calculator that calculates a target compressor driving force, which is a target value of driving force for the compressor; a real compressor driving force calculator that calculates real compressor driving force, which is a real value of driving force for the compressor; a supercharger inertial force calculator that calculates inertial force produced by an inertial moment of the supercharger, based on the real rotation speed of the supercharger; and a gate valve control value calculator that implements driving force feedback control for changing a gate valve control value, which is a control value for the gate valve actuator, so that an addition value obtained by adding the inertial force to the real compressor driving force approaches the target compressor driving force, and performs driving control of the wastegate valve based on the gate valve control value.

2 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 , wherein the supercharger inertial force calculator adopts, as the final inertial force, a value obtained by applying upper/lower limitation with preliminarily set upper limit and lower limit values to the calculation value of the inertial force, which is calculated based on the real rotation speed of the supercharger.

3 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 , wherein in the case where the calculation value of the inertial force, calculated based on the real rotation speed of the supercharger, is within a preliminarily set falling range including zero, the supercharger inertial force calculator adopts, as the final inertial force, a value decreased so as to be smaller than the calculation value.

4 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 , wherein based on the real rotation speed of the supercharger, the supercharger inertial force calculator calculates a real rotation acceleration of the supercharger, and then calculates, as the inertial force, a value obtained by multiplying the real rotation acceleration of the supercharger by the inertial moment and the real rotation speed of the supercharger.

5 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 ,
wherein the driving-condition detector detects a real intake air flow rate of the internal combustion engine, a real atmospheric pressure, and a real supercharging pressure that is a real value of a supercharging pressure, which is a pressure at a position, in the intake path, that is at the downstream side of the compressor and at the upstream side of the throttle valve, and wherein the real compressor driving force calculator calculates the real compressor driving force, based on the real intake air flow rate and a real before/after-compressor pressure ratio, which is the pressure ratio of the real supercharging pressure and the real atmospheric pressure.

6 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 ,
wherein the driving-condition detector detects the real rotation speed of the supercharger, based on an output signal of a rotation speed sensor provided in the supercharger, and wherein, alternatively, the driving-condition detector detects a real intake air flow rate of the internal combustion engine, a real atmospheric pressure, and a real supercharging pressure that is a real value of a supercharging pressure, which is a pressure at a position, in the intake path portion, that is at the downstream side of the compressor and at the upstream side of the throttle valve, and then detects the real rotation speed of the supercharger, based on the real intake air flow rate, the real before/after-compressor pressure ratio, which is the pressure ratio of the real supercharging pressure and the real atmospheric pressure.

7 . The controller for an internal combustion engine equipped with a supercharger according to claim 1 , further comprising
an intake air controller that calculates a target intake air flow rate and a target charging efficiency of the internal combustion engine, and a target supercharging pressure calculator that calculates a target supercharging pressure, which is a target value of a supercharging pressure that is the pressure at a position, in the intake path portion, that is at the downstream side of the compressor and at the upstream side of the throttle valve, based on the target charging efficiency and a real rotation speed of the internal combustion engine, which is detected by the driving-condition detector, wherein the target compressor driving force calculator calculates the target compressor driving force, based on the target intake air flow rate and a target before/after-compressor pressure ratio, which is the pressure ratio of the target supercharging pressure and the real atmospheric pressure detected by the driving-condition detector, and wherein the gate valve control value calculator calculates an exhaust gas flow rate discharged from the internal combustion engine, based on a real intake air flow rate of the internal combustion engine, which is detected by the driving-condition detector, and an air-fuel ratio of the internal combustion engine, calculates a basic value of the gate valve control value, based on the target compressor driving force and the exhaust gas flow rate, and then calculates, as the final gate valve control value, a value obtained by correcting the basic value through the driving force feedback control.

Assignees

• Mitsubishi Electric Corp
• Mazda Motor

Inventors

• Inoue Junichi
• Ono Takahiko
• Maruo Toshiaki
• Nishio Takafumi
• Sunagare Yugou

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02D41/1497

  With detection of the mechanical response of the engine · CPC title

• F02D41/18

  by measuring intake air flow · CPC title

• F02B37/183 Primary

  Arrangements of bypass valves or actuators therefor · CPC title

• F02D41/0007

  for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12) · CPC title