Control apparatus for power supply system

Patent metadata

Field	Value
Publication number	US-10082121-B2
Application number	US-201715607794-A
Country	US
Kind code	B2
Filing date	May 30, 2017
Priority date	May 31, 2016
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

In a control apparatus mounted in a vehicle supporting start-stop control, for controlling a power supply system, a target charge level setter variably sets a target charge level of a second rechargeable battery when an internal-combustion engine of the vehicle is operating. The target charge level setter sets the target charge level to a higher level as load current increases, and when setting the target charge level, performs at least one of subtracting a first load quantity indicative of a current that is supplied to first electrical loads from a detected value of the load current and adding a second load quantity indicative of a current that is supplied to second electrical loads to the detected value of the load current. The first electrical loads operate when the internal-combustion engine is operating, and the second electrical loads operate when the engine is not operating.

First claim

What is claimed is:

1. A control apparatus mounted in a vehicle supporting start-stop control to stop the operation of an internal-combustion engine when the vehicle is not moving, the apparatus being configured to control a power supply system comprising:
an alternator connected to an output shaft of the internal-combustion engine and configured to perform power generation by rotation of the output shaft of the internal-combustion engine;
a first rechargeable battery that can be charged with electrical power generated by the alternator;
a second rechargeable battery electrically connected in parallel with the first rechargeable battery through a switch;
electrical loads electrically connected to the second rechargeable battery side of the switch, the electrical loads including first electrical loads that operate when the internal-combustion engine is operating, and second electrical loads that operate when the internal-combustion engine is not operating, and
a current detector configured to detect a load current that is a current supplied to the electrical load side, wherein the control apparatus comprises:
a current value acquirer configured to acquire a value of the load current detected by the current detector;
a power generation controller configured to operate the alternator such that a charge level of the second rechargeable battery becomes a target charge level;
a target charge level setter configured to variably set the target charge level of the second rechargeable battery when the internal-combustion engine is operating, the target charge level setter being further configured to set the target charge level of the second rechargeable battery to a higher level as the load current increases, and when setting the target charge level, perform at least one of subtracting a first load quantity indicative of a current that is supplied to the first electrical loads from the detected value of the load current and adding a second load quantity indicative of a current that is supplied to the second electrical loads to the detected value of the load current; and
a connection controller configured to place the switch in a nonconducting state when idling of the internal-combustion engine is stopped.

2. The apparatus according to claim 1 , wherein the target charge level setter is configured to, when the first electrical loads are not operating, limit the subtraction of the first load quantity when setting the target charge level of the second rechargeable battery.

3. The apparatus according to claim 1 , wherein the target charge level setter is configured to, when the second electrical loads are operating, limit the addition of the second load quantity when setting the target charge level of the second rechargeable battery.

4. The apparatus according to claim 1 , wherein
the target charge level setter is configured to variably set the target charge level of the second rechargeable battery when the internal-combustion engine is not operating, and
the target charge level setter is further configured to, when the internal-combustion engine is not operating, limit the subtraction of the first load quantity and the addition of the second load quantity when setting the target charge level of the second rechargeable battery.

5. The apparatus according to claim 1 , wherein
the power supply system further comprises a first detector configured to detect a current supplied to the first electrical loads,
the current value acquirer is further configured to acquire a value of the current detected by the first detector, and
the target charge level setter is configured to set the first load quantity to the value of the current detected by the first detector.

6. The apparatus according to claim 1 , wherein
the power supply system further comprises a second detector configured to detect a current supplied to the second electrical loads,
the current value acquirer is further configured to acquire a value of the current detected by the second detector, and
the target charge level setter is configured to set the second load quantity to a value obtained by subtracting the value of the current detected by the second detector from a reference value based on the consumption current of the second electrical loads in a predetermined operating state.

Assignees

• Denso Corp

Inventors

• Morita Yoshinori

Classifications

• H02J7/865

  Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence) · CPC title

• H02J7/825

  Detection of fully charged condition · CPC title

• F02N2200/0801

  Vehicle speed · CPC title

• F02N11/0814

  comprising means for controlling automatic idle-start-stop · CPC title

• F02N11/0866 Primary

  comprising several power sources, e.g. battery and capacitor or two batteries · CPC title