Control device of internal-combustion engine

Patent metadata

Field	Value
Publication number	US-2018266341-A1
Application number	US-201815910011-A
Country	US
Kind code	A1
Filing date	Mar 2, 2018
Priority date	Mar 17, 2017
Publication date	Sep 20, 2018
Grant date	—

Abstract

A control device of an internal-combustion engine capable of improving merchantability by promptly and appropriately securing an in-cylinder fresh air amount even when an internal-combustion engine including a boost device and an EGR device is in a transient operation state is provided. A control device 1 includes an ECU 2. The ECU 2 calculates an intake air amount GGAScyl, sets an upper-limit target fresh air amount GAIR_hisH, controls a boost operation of a boost device 7 when an operating range of an internal-combustion engine 3 is in a predetermined boost range, and controls an EGR device 5 so that exhaust gas recirculation is stopped when the intake air amount GGAScyl does not reach an upper-limit target fresh air amount GAIR_hisH and the exhaust gas recirculation is executed when the intake air amount GGAScyl reaches the upper-limit target fresh air amount GAIR_hisH in the predetermined boost range.

First claim

What is claimed is:

1 . A control device of internal-combustion engine, the internal-combustion engine including a boost device and an EGR device, the control device comprising:
an intake gas amount acquiring unit which acquires an amount of a gas flowing into a cylinder of the internal-combustion engine as an intake gas amount; a target fresh air amount setting unit which sets a target fresh air amount as a target for an in-cylinder fresh air amount which is an amount of fresh air flowing into the cylinder of the internal-combustion engine; a boost control unit which controls a boost operation of the boost device when an operating range of the internal-combustion engine is in a predetermined boost range; and an EGR control unit which controls the EGR device so that exhaust gas recirculation is stopped when the intake gas amount does not reach the target fresh air amount and the exhaust gas recirculation is executed when the intake gas amount reaches the target fresh air amount in a case where the operating range of the internal-combustion engine is in the predetermined boost range.

2 . The control device of the internal-combustion engine according to claim 1 ,
wherein the boost device includes a compressor which is provided in an intake passage of the internal-combustion engine and a turbine which is provided in an exhaust passage of the internal-combustion engine, wherein the EGR device includes an EGR passage which is connected between a downstream portion in relation to the turbine of the exhaust passage and an upstream portion in relation to the compressor of the intake passage, an EGR valve which changes an amount of a recirculation gas flowing inside the EGR passage, and a differential pressure generating valve which is provided at an upstream side in relation to a connection portion between the intake passage and the EGR passage and generates a differential pressure between upstream and downstream sides of the EGR valve, and wherein when the intake gas amount reaches the target fresh air amount, the EGR control unit controls the EGR valve so that the recirculation gas flows inside the EGR passage and controls the differential pressure generating valve such that a differential pressure is generated.

3 . The control device of the internal-combustion engine according to claim 2 ,
wherein the target fresh air amount setting unit sets a basic target fresh air amount and an upper-limit target fresh air amount larger than the basic target fresh air amount by a predetermined value as the target fresh air amount, wherein the EGR control unit controls the EGR device so that the exhaust gas recirculation is stopped until the intake gas amount reaches the upper-limit target fresh air amount and the exhaust gas recirculation is executed after the intake gas amount reaches the upper-limit target fresh air amount when the operating range of the internal-combustion engine is in the predetermined boost range, and wherein the predetermined value is set to a value in which the intake gas amount does not become smaller than the basic target fresh air amount when the control of the differential pressure generating valve is executed.

4 . The control device of the internal-combustion engine according to claim 2 ,
wherein the EGR control unit controls an opening degree of the differential pressure generating valve such that the opening degree becomes a maximal opening degree in which a differential pressure is not generated until the intake gas amount reaches the target fresh air amount.

5 . The control device of the internal-combustion engine according to claim 2 ,
wherein the EGR control unit controls an opening degree of the differential pressure generating valve to become a predetermined standby opening degree until the intake gas amount reaches the target fresh air amount, and wherein the predetermined standby opening degree is set to a value larger than an effective opening degree of the differential pressure generating valve and smaller than a maximal opening degree in which no differential pressure is generated.

6 . The control device of the internal-combustion engine according to claim 2 ,
wherein the intake gas amount acquiring unit calculates a basic intake gas amount in response to the operation state of the internal-combustion engine and calculates the intake gas amount by executing a filtering process giving a predetermined response delay characteristic for the basic intake gas amount.

Assignees

• Honda Motor Co Ltd

Inventors

• Ueno Masaki
• Kimura Noritaka
• Ihara Kosuke
• Katori Yuto
• Yamada Yosuke
• Uto Hajime

Classifications

• F02D2041/1431

  the system including an input-output delay · CPC title

• F02D41/005 Primary

  according to engine operating conditions · CPC title

• F02D2200/0411

  Volumetric efficiency · CPC title

• F02M26/06

  Low pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust downstream of the turbocharger turbine and reintroduced into the intake system upstream of the compressor · CPC title

• F02D2200/0406

  Intake manifold pressure · CPC title