Energy economy mode using preview information
A method for improving energy efficient operation of a vehicle includes monitoring vehicle operating characteristics, modeling operation of the vehicle by utilizing the vehicle operating characteristics to estimate energy consumption rates of the vehicle across an allowable vehicle operating range, and generating a control output to the vehicle on the basis of the energy consumption rates.
1. A method for improving energy efficient operation of a vehicle, wherein a microprocessor performs the following steps:
monitoring vehicle operating characteristics comprising analyzing vehicle load and road topology and analyzing at least one of weather conditions, traffic conditions, road conditions, tire pressure, vehicle maintenance history, and driver operating patterns;
modeling operation of said vehicle, said modeling utilizing said vehicle operating characteristics to estimate energy consumption rates of said vehicle across an allowable speed range, wherein said allowable speed range comprises a maximum allowable speed corresponding to a maximum legal speed and a minimum allowable speed some speed interval less than said maximum legal speed;
determining a potential control speed within the allowable speed range on the basis of said energy consumption rates; and
generating a control output to said vehicle comprising setting a control speed based upon the potential control speed.
2. The method of claim 1 , further comprising defining said allowable speed range with at least one of a minimum allowable speed and a maximum allowable speed.
3. The method of claim 1 , further comprising defining a desired speed within said allowable speed range; and
wherein setting said control speed based upon said potential control speed comprises:
selecting between said desired speed and said potential control speed by balancing an energy consumption differential between an energy consumption rate at said desired speed and an energy consumption rate at said potential control speed against a speed differential between said desired speed and said potential control speed.
4. The method of claim 1 , further comprising selecting a hybrid operating state defining selection of fuel power and battery power for said vehicle.
5. The method of claim 1 , further comprising selecting a transmission gear state for said vehicle.
6. The method of claim 1 , further comprising selecting a hybrid operating state defining selection of fuel power and battery power for said vehicle and a transmission gear state for said vehicle.
7. The method of claim 1 , further comprising projecting said energy consumption rates across said allowable speed range over a planned travel route.
8. The method of claim 7 , further comprising generating a speed change schedule on the basis of said projected energy consumption rates.
9. The method of claim 8 , said method further comprising updating said speed change schedule in coordination with an adaptive cruise control module.
10. The method of claim 7 , further comprising generating a transmission shift strategy on the basis of said projected energy consumption rates.
11. The method of claim 7 , further comprising generating a hybrid powertrain energy consumption schedule on the basis of said projected energy consumption rates.
12. The method of claim 11 , further comprising generating a hybrid powertrain battery charging schedule on the basis of said projected energy consumption rates.
13. The method of claim 7 , further comprising generating travel route recommendations on the basis of said projected energy consumption rates.
14. The method of claim 1 , further comprising:
operating said vehicle under cruise control;
determining the potential control speed within said allowable speed range and a corresponding transmission gear state on the basis of said energy consumption rates;
selecting a cruise speed and a transmission gear state command based upon the potential control speed and the corresponding transmission gear state; and
controlling the vehicle based upon the cruise speed and the transmission gear state command.
15. The method of claim 14 , further comprising previewing potential future vehicle operating characteristics based on a planned travel route, wherein said selecting a cruise speed includes forming a speed control strategy and a transmission gear state strategy over said planned travel route.