Method to adjust fuel economy readings for stored energy

• US 9,367,972 B2
• Filed: 04/21/2014
• Issued: 06/14/2016
• Est. Priority Date: 04/21/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Ulrey, Joseph Norman, Pursifull, Ross Dykstra, Ruona, William Charles
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): PECHE, JORGE O
• Application Number:
  US14/257,890
• Publication Number:
  US 20150302670A1
• Time in Patent Office: 785 Days
• Field of Search: 701/104, 701/103, 701/123
• US Class Current: 1/1
• CPC Class Codes: B60K 2360/174 Economic driving
• CPC Class Codes: B60K 35/28 characterised by the type of the output information, e.g. video entertainment or vehicle dynamics information; characterised by the purpose of the output information, e.g. for attracting the attention of the driver
• CPC Class Codes: B60K 35/60 Instruments characterised by their location or relative disposition in or on vehicles arrangements of lighting devices on dashboards B60Q3/10
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2552/25 Road altitude
• CPC Class Codes: B60W 40/00 Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
• CPC Class Codes: G01F 9/023 with electric, electro-mechanic or electronic means
• CPC Class Codes: G07C 5/0816 Indicating performance data, e.g. occurrence of a malfunction
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration

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.

Claims

1. A method for a vehicle, comprising:

when the vehicle undergoes a positive change in a square of vehicle speed greater than a threshold and/or a positive change in vehicle altitude that is greater than a vehicle altitude threshold;

estimating a fuel flow due to stored vehicle energy by subtracting a fuel flow rate determined during steady state driving conditions from an existing fuel flow rate;

estimating a conversion factor for stored vehicle energy, the conversion factor directly proportional to the estimated fuel flow; and

adjusting a fuel economy reading by the estimated conversion factor and displaying the adjusted fuel economy reading to an operator of the vehicle.

2. The method of claim 1, wherein the conversion factor is inversely proportional to each of the change in square of vehicle speed and the change in vehicle altitude.

3. The method of claim 1, wherein the steady state driving conditions include conditions when changes in each of the square of vehicle speed and vehicle altitude are below their respective thresholds.

4. The method of claim 1, wherein the adjusted fuel economy reading is displayed to the operator of the vehicle at periodic intervals.

5. The method of claim 1, wherein stored vehicle energy is one or both of potential energy and kinetic energy, and wherein potential energy is directly proportional to vehicle altitude, and kinetic energy is directly proportional to square of vehicle speed.

6. The method of claim 1, wherein the change in vehicle altitude is estimated based on grade readings from an inclinometer and vehicle speed.

7. The method of claim 6, wherein the grade readings from the inclinometer are corrected for offset error by comparison with readings from a barometric pressure sensor.