Control device and method for internal combustion engine

Patent metadata

Field	Value
Publication number	US-9970369-B2
Application number	US-201313927909-A
Country	US
Kind code	B2
Filing date	Jun 26, 2013
Priority date	Oct 24, 2012
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

Provided is a control unit ( 1 ) for setting, for respective electronic throttles ( 11 ) and ( 12 ) provided for respective cylinders, respective ranges of a difference between a target rpm and an engine rpm where the electronic throttles ( 11 ) and ( 12 ) are not operated as a first dead zone and a second dead zone, determining, for each of the electronic throttles ( 11 ) and ( 12 ), whether or not the difference between the target rpm and the engine rpm is in the dead zone, preventing the electronic throttle determined to have the difference in the dead zone from operating, and determining, for the electronic throttle determined to have the difference exceeding the dead zone, a control gain for the electronic throttle depending on the magnitude of the difference, thereby operating the electronic throttle.

First claim

What is claimed is:

1. A control device for an internal combustion engine for controlling an engine rpm of the internal combustion engine, the internal combustion engine including a plurality of cylinders and independently controllable electronic throttles for the respective cylinder, the control device comprising:
an engine rpm sensor configured to detect the engine rpm of the internal combustion engine; and
a controller configured to:
set a target rpm based on an operation state of a vehicle in which the internal combustion engine is provided;
detect a difference between the target rpm and the engine rpm of the internal combustion engine; and
independently control the plurality of electronic throttles based on a magnitude of the detected difference so as to increase or decrease an intake air amount so that the target rpm and the engine rpm of the internal combustion engine match each other,

wherein the controller is further configured to:
set, to each of the electronic throttles, a respective dead zone in which the respective electronic throttle is prevented from being operated, wherein the respective dead zones have different ranges of the detected difference and are overlapping with one another;
determine, for the each of the plurality of the electronic throttles, whether or not the difference detected by the controller is in the respective dead zone set for the respective throttle;
in response to determining that one of the plurality of the electronic throttles has the difference in the dead zone, prevent the electronic throttle from operating; and
in response to determining that one of the plurality of the electronic throttles has the difference exceeding the dead zone, determine a control gain for said one electronic throttle depending on the magnitude of the difference detected by the controller so as to operate the electronic throttle.

2. The control device for an internal combustion engine according to claim 1 , wherein the controller independently sets the control gains for the respective plurality of electronic throttles.

3. The control device for an internal combustion engine according to claim 1 , wherein:
the dead zone set to the each of the plurality of the electronic throttles includes a first dead zone and a second dead zone; and
the controller sets the second dead zone to be a larger range than a range for the first dead zone, and sets a control gain for one of the plurality of the electronic throttles which is prevented from operating in the second dead zone to be a larger value than a value of a control gain for one of the plurality of the electronic throttles which is prevented from operating in the first dead zone.

4. The control device for an internal combustion engine according to claim 1 , wherein the controller is further configured to:
set, based on the control gain, target values of the intake air amounts independently controlled by the respective plurality of the electronic throttles; and
set again, when a difference between the target values of the intake air amounts exceeds a predetermined value, the target values so that the difference does not exceed the predetermined value.

5. The control device for an internal combustion engine according to claim 1 , wherein the target rpm comprises a target rpm in an idle state.

6. The control method for an internal combustion engine for controlling an engine rpm of the internal combustion engine, the internal combustion engine including a plurality of cylinders and independently controllable electronic throttles for the respective cylinder, the control method comprising:
setting, to each of the electronic throttles, a respective dead zone in which the respective electronic throttle is prevented from being operated, wherein dead zones have different range values of a difference between a target rpm and the engine rpm of the internal combustion engine, from one another and are overlapping ranges with respect to one another;
setting the target rpm based on an operation state of a vehicle in which the internal combustion engine is provided;
detecting the difference between the target rpm and the engine rpm of the internal combustion engine;
determining, for the each of the electronic throttles, whether or not the detected difference is in the set, respective dead zone; and
preventing one of the electronic throttles determined to have the difference in the respective dead zone from operating, and determining, for one of the electronic throttles determined to have the difference exceeding the dead zone, a control gain for the electronic throttle depending on the magnitude of the detected difference so as to operate the one of the electronic throttles.

7. The control device for an internal combustion engine according to claim 1 , wherein:
the electronic throttles comprise a first throttle for which a first dead zone is set and a second throttle for which a second dead zone is set,
the first dead zone is a smaller range of the detected difference than the second dead zone,
the controller is further configured to set, based on the detected difference, a first control gain for the first throttle and a second control gain for the second throttle,
the second control gain is a larger value than the first control gain in the detected difference outside of the dead zones, and
the controller is configured to independently set the first control gain for the first throttle and the second control gain for the second throttle so as to independently control opening degrees of the first throttle and the second throttle.

8. The control method for an internal combustion engine according to claim 6 , wherein:
the electronic throttles comprise a first throttle for which a first dead zone is set and a second throttle for which a second dead zone is set,
the first dead zone is a smaller range of the detected difference than the second dead zone,
the setting further comprises setting, based on the detected difference, a first control gain for the first throttle and a second control gain for the second throttle,
the second control gain is a larger value than the first control gain in the detected difference outside of the dead zones, and
the setting further comprises independently setting the first control gain for the first throttle and the second control gain for the second throttle so as to independently control opening degrees of the first throttle and the second throttle.

Assignees

• Mitsubishi Electric Corp

Inventors

• Takahashi Shingo
• Nomura Masahiko

Classifications

• F02D41/008

  Controlling each cylinder individually · CPC title

• F02D2041/1422

  Variable gain or coefficients · CPC title

• F02D41/0087

  Selective cylinder activation, i.e. partial cylinder operation (deceleration cut-off F02D41/123) · CPC title

• F02D31/003

  for idle speed control · CPC title

• F02D41/0082 Primary

  per groups or banks (F02D41/0087 takes precedence) · CPC title