Method for the management of the electrical current supply in a motor vehicle

• US 10,145,901 B2
• Filed: 05/13/2015
• Issued: 12/04/2018
• Est. Priority Date: 05/15/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Eifert, Mark
• Primary Examiner(s): Ngo, Brian
• Application Number:
  US14/711,122
• Publication Number:
  US 20150331060A1
• Time in Patent Office: 1,301 Days
• Field of Search: 320132, 320109, 320135, 320155
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/374 with means for correcting the measurement for temperature or ageing
• CPC Class Codes: H02J 7/1446 in response to parameters of a vehicle
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

This disclosure relates to a method for the management of the electrical current supply in a motor vehicle having a combustion engine, wherein the charge state of a battery is detected and characterized as a discrete variable that indicates whether the prevailing charge state is below or above a calibrated threshold value. If the discrete variable indicates that the prevailing charge state is below the calibrated threshold value, the battery is charged using a relatively high voltage over a predetermined time period in such a manner that all cells of the battery are charged. If the discrete variable indicates that the prevailing charge state is above the calibrated threshold value, different temperature-dependent voltage set points of an electric generator in the vehicle are set in dependence upon a prevailing energy conversion efficiency level of the drivetrain that is detected and characterized as a further discrete variable.

Claims

1. A method for managing current supply in a vehicle comprising:

in response to a discrete variable generated using a battery monitoring sensor indicating that a charge state of a battery is less than a calibrated threshold value, charging the battery using a voltage setpoint over a predetermined time period such that cells of the battery are charged to a target; and

in response to the discrete variable indicating that the charge state is greater than the calibrated threshold value, setting a voltage setpoint for an electric generator based on a parameter indicative of drivetrain efficiency and a parameter indicative of temperature of the battery.

2. The method as claimed in claim 1 further comprising monitoring current of the battery during a transition from a higher voltage set point to a lower voltage set point during a predetermined time period to determine whether the discrete variable indicates that the charge state is less than or greater than the calibrated threshold value.

3. The method as claimed in claim 1, wherein the voltage setpoint for the electric generator is further set based on whether the vehicle is decelerating.

4. The method as claimed in claim 1 further comprising determining the parameter indicative of drivetrain efficiency based on an accelerator pedal position, a velocity of the vehicle, and a rotational speed of an engine.

5. The method as claimed in claim 1 further comprising using a stored value for the discrete variable from a last drive cycle upon restart of the vehicle.

6. The method as claimed in claim 1, wherein the parameter indicative of drivetrain efficiency is a binary parameter.

7. The method as claimed in claim 1, wherein the discrete variable is a binary parameter.

8. A method comprising:

by a controller,

responsive to a discrete variable generated using a battery monitoring sensor indicating state of charge (SOC) less than a threshold, operating a generator at a voltage setpoint for a predetermined duration such that battery cells are charged to a target; and

responsive to the discrete variable indicating SOC greater than the threshold, operating the generator at a voltage setpoint set according to drivetrain efficiency and battery temperature.

9. A method for management of electrical current supply in a vehicle having a combustion engine, wherein a charge state of a battery that can provide current for a starter, ignition and lighting is detected and characterized as a discrete variable generated using a battery monitoring sensor that indicates whether the charge state is below or above a calibrated threshold value, the method comprising:

if the discrete variable indicates that the charge state is below the calibrated threshold value, charging the battery using a voltage setpoint over a predetermined time period in such a manner that cells of the battery are charged; and

if the discrete variable indicates that the charge state is above the calibrated threshold value, in dependence upon a drivetrain energy conversion efficiency level that is detected and characterized as a further discrete variable, setting different temperature-dependent voltage set points of an electric generator in the vehicle.

10. The method as claimed in claim 9, wherein the temperature-dependent voltage set points in addition comprise a function for operation of the battery as an energy buffer for a regenerative braking operation, wherein the voltage set point is selected not only with reference to the further discrete variable that characterizes the drivetrain energy conversion efficiency level as being low or high but rather also with reference to a further discrete variable that characterizes the drivetrain energy conversion efficiency level as very high as a result of deceleration of the vehicle without fuel supply.

11. The method as claimed in claim 10, wherein the drivetrain energy conversion efficiency level is identified as being low, high or very via monitoring of accelerator pedal position, vehicle velocity, and engine rotational speed.