Method to adjust fuel economy readings for stored energy

Patent metadata

Field	Value
Publication number	US-10163279-B2
Application number	US-201615159648-A
Country	US
Kind code	B2
Filing date	May 19, 2016
Priority date	Apr 21, 2014
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

Methods and systems are provided for compensating an instantaneous fuel economy reading for stored energy. One method comprises, when a vehicle undergoes a sufficient change in one or more of square of vehicle speed and vehicle altitude, estimating a conversion factor for fuel due to stored vehicle energy and adjusting the instantaneous fuel economy reading by the estimated conversion factor. The adjusted instantaneous fuel economy reading may be displayed to an operator of the vehicle.

First claim

The invention claimed is:

1. A method for vehicle operation with an engine, comprising:
sensing fuel flow and vehicle speed;
determining a fuel economy at steady-state driving conditions based on fuel flow and vehicle speed;
sensing a brake pedal position;
during non-braking conditions, estimating a conversion factor for stored vehicle energy based on the fuel economy at steady-state driving conditions;
waiting to estimate the conversion factor during braking conditions; and
displaying a fuel economy reading to an operator of a vehicle based on fuel consumed by the engine adjusted for stored vehicle energy with the conversion factor.

2. The method of claim 1 , wherein steady-state driving conditions include conditions when changes in each of a square of vehicle speed and vehicle altitude are below their respective thresholds, the conversion factor based on sensor signals.

3. The method of claim 2 , wherein the conversion factor for stored vehicle energy is determined when the square of vehicle speed is increased greater than a first vehicle speed threshold and vehicle altitude is increased greater than a second altitude threshold.

4. The method of claim 2 , wherein the conversion factor for stored vehicle energy is directly proportional to fuel flow due to stored vehicle energy and inversely proportional to each of a change in the square of vehicle speed and a change in vehicle altitude, the change in vehicle altitude measured by an inclinometer and corrected for offset error.

5. The method of claim 4 , wherein the fuel flow due to stored vehicle energy is determined by subtracting a fuel flow rate based on the fuel economy at steady-state driving conditions from an existing fuel flow rate.

6. The method of claim 1 , wherein the conversion factor for stored vehicle energy and the fuel economy at steady-state driving conditions are determined after engine warm up.

7. The method of claim 1 , wherein the conversion factor for stored vehicle energy and the fuel economy at steady-state driving conditions are not determined during transmission shifts.

8. The method of claim 1 , wherein the conversion factor for stored vehicle energy and the fuel economy at steady-state driving conditions are not determined during vehicle braking conditions.

9. A system in a vehicle comprising:
an engine; and
a controller configured with computer readable instructions stored in non-transitory memory to:
during a first braking mode,
determine a fuel economy reading; and
waiting to estimate a conversion factor for stored vehicle energy;

during a second non-braking mode,
determine the conversion factor for stored vehicle energy based on the fuel economy reading determined in the first braking mode; and
display instantaneous fuel economy readings, which are compensated for stored vehicle energy by using the conversion factor, to an operator of the vehicle.

10. The system of claim 9 , wherein the first braking mode includes steady-state driving conditions, and wherein the second non-braking mode includes only conditions when an increase in a square of vehicle speed is higher than a vehicle speed threshold and/or when an increase in vehicle altitude is higher than a vehicle altitude threshold.

Assignees

• Ford Global Tech Llc

Inventors

• Ulrey Joseph Norman
• Pursifull Ross Dykstra
• Ruona William Charles

Classifications

• B60W2552/25

  Road altitude · CPC title

• G07C5/0816 Primary

  Indicating performance data, e.g. occurrence of a malfunction · CPC title

• B60R16/0236 Primary

  for economical driving · CPC title

• B60W2520/10

  Longitudinal speed · CPC title

• Y02T10/84

  Data processing systems or methods, management, administration · CPC title