Control apparatus

Patent metadata

Field	Value
Publication number	US-11370408-B2
Application number	US-201916366096-A
Country	US
Kind code	B2
Filing date	Mar 27, 2019
Priority date	Mar 28, 2018
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

A control apparatus is used with a vehicle including an engine, a storage battery, and an electrical load. The control apparatus works as an automatic engine stop and restart system and calculates a SOC lower limit that is a minimum value of state of charge (SOC) of the battery required to continue to stop the engine in an idle stop mode. The control apparatus also calculates an amount of electric power expected to be consumed by the electrical load during the idle stop mode and determines an idle stop enable SOC at which the idle stop mode is entered and which is selected to be the sum of the SOC lower limit and a SOC of the battery which at least compensates for the consumed amount of electric power. This ensures chances to stop the engine in the idle stop mode and improves fuel economy.

First claim

What is claimed is:

1. A control apparatus configured to be used in a vehicle having an internal combustion engine, a starter configured to start the internal combustion engine, a chargeable and dischargeable storage battery, and an electrical load which is configured to be supplied with electric power from the storage battery, comprising:
a stop controller configured to stop the internal combustion engine in an idle stop mode when an automatic stop condition is met;
a start controller configured to control an operation of the starter to restart the internal combustion engine when a restart condition is met during the idle stop mode;
a lower limit calculator configured to calculate a SOC lower limit using a state of the storage battery, the SOC lower limit being a state of charge of the storage battery required to continue to stop the internal combustion engine in the idle stop mode;
a consumed power calculator configured to calculate a consumed amount of electric power that is an amount of electric power expected to be consumed by the electrical load during a stop of the internal combustion engine in the idle stop mode; and
a SOC determiner configured to determine an idle stop enable SOC that is a state of charge of the storage battery that permits the idle stop mode to be entered to stop the internal combustion engine, the idle stop enable SOC is the sum of the SOC lower limit and a SOC of the storage battery that is at least the consumed amount of electric power calculated by the consumed power calculator,
wherein the control apparatus is configured such that the stop controller does not stop the internal combustion engine in the idle stop mode when the idle stop enable SOC is less than the state of charge of the storage battery.

2. A control apparatus as set forth in claim 1 , wherein the lower limit calculator is configured such that the SOC lower limit is a function of a minimum value of state of charge of the storage battery required to restart the internal combustion engine.

3. A control apparatus as set forth in claim 1 , wherein the lower limit calculator is configured such that the SOC lower limit is based on a minimum value of state of charge of the storage battery required to output an amount of electric power which ensures stability in operation of the electrical load during the idle stop mode.

4. A control apparatus as set forth in claim 1 , wherein:
the vehicle includes an electrical generator configured to generate electric power using drive energy from the internal combustion engine or kinetic energy of the vehicle;
the storage battery is chargeable using the electric power from the electrical generator;
the control apparatus includes power generation controller configured to control an operation of the electrical generator to bring a state of charge of the storage battery to be higher than or equal to a target state of charge; and
the target state of charge is higher than the idle stop enable SOC.

5. A control apparatus as set forth in claim 4 , wherein the power generation controller is configured such that, when a state of charge of the storage battery is lower than the target state of charge after termination of stop of the internal combustion engine in the idle stop mode, the power generation controller actuates the electrical generator to produce electric power using the drive energy from the internal combustion engine or the kinetic energy of the vehicle until the target state of charge is reached.

6. A control apparatus as set forth in claim 4 , wherein the SOC determiner is configured such that the idle stop enable SOC is determined only within a time interval between stopping of the internal combustion engine in the idle stop mode and when a state of charge of the storage battery is increased to reach the target state of charge.

7. A control apparatus as set forth in claim 4 , wherein the SOC determiner is configured such that the idle stop enable SOC is determined when it is determined using a travel history of the vehicle or information about surroundings of the vehicle that a time interval between termination of the idle stop mode and subsequent satisfaction of the automatic stop condition is shorter than a given value.

8. A control apparatus as set forth in claim 1 , wherein the consumed power calculator is configured such that the consumed power calculator calculates the consumed amount of electric power based on a travel history of the vehicle.

9. A control apparatus as set forth in claim 8 , wherein the consumed power calculator is configured such that, when determining based on the travel history that a frequency of entry of the idle stop mode is large or a length of time the internal combustion engine is kept stopped in the idle stop mode is long, the consumed power calculator calculates the consumed amount of electric power to be larger than that when determining that the frequency of entry of the idle stop mode is small or the length of time the internal combustion engine is kept stopped in the idle stop mode is short.

10. A control apparatus as set forth in claim 1 , wherein the consumed power indicator is configured such that the consumed power calculator calculates the consumed amount of electric power based on information about surroundings of the vehicle.

11. A control apparatus as set forth in claim 10 , wherein the consumed power indicator is configured such that, when determining based on the information about surroundings of the vehicle that there is a traffic jam, a width of a road is large, or the number of times the vehicle passes through traffic lights is large, the consumed power calculator calculates the consumed amount of electric power to be larger than that when determining based on the information about surroundings of the vehicle that the traffic is light, the width of the road is narrow, or the number of times the vehicle passes through traffic lights is small.

12. A control apparatus as set forth in claim 1 , wherein the start controller is configured to restart the internal combustion engine based on comparison of a state of charge of the storage battery with the SOC lower limit before the restart condition is met.

Assignees

• Denso Corp

Inventors

• Morita Yoshinori

Classifications

• F02N11/0818

  Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode · CPC title

• B60W2555/60

  Traffic rules, e.g. speed limits or right of way · CPC title

• B60W20/00 Primary

  Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} · CPC title

• B60W10/08

  including control of electric propulsion units, e.g. motors or generators · CPC title

• F02D29/06

  peculiar to engines driving electric generators · CPC title