Vehicle platooning with a hybrid electric vehicle system
A system and method are provided for controlling the operation of a vehicle equipped with a hybrid electric front end motor-generator system during vehicle platooning operations to maintain a predetermined separation distance between vehicles in the vehicle platoon. The motor-generator is operated to generate vehicle acceleration and deceleration by outputting torque to an engine crankshaft to accelerate the vehicle or generating a regenerative braking load via the crankshaft on the vehicle, in place of the vehicle's internal combustion engine and braking systems, when the required vehicle accelerations and/or decelerations needed to maintain the desired vehicle separation distance are small and within the torque output or torque load capacity of the motor-generator. If the required vehicle acceleration or deceleration is greater than the motor-generator's available capacity, the motor-generator may be operated to provide a portion of the required acceleration or deceleration, as a supplement to the acceleration provided by the engine or the deceleration provided by the braking system. The use of a front end motor-generator system in this manner increases overall vehicle energy efficiency by decreasing fuel consumption and increasing the amount of electrical energy captured for storage during vehicle platooning operations.
1. A method of operating a vehicle having an internal combustion engine and a hybrid electric front end motor-generator system, comprising the acts of:
receiving, at a wireless transceiver of the vehicle, vehicle platooning information from at least one other vehicle;
determining with a vehicle controller whether the vehicle and the at least one other vehicle are operating in a platooning mode in which operation of the vehicle and the at least one other vehicle are coordinated such that at least one predetermined multi-vehicle operating parameter is maintained;
if the vehicle is in platooning mode, maintaining the at least one predetermined multi-vehicle operating parameter by
determining with the vehicle controller whether the vehicle is to be accelerated or decelerated to maintain the at least one predetermined multi-vehicle operating parameter,
determining with the vehicle controller a required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter,
determining with the vehicle controller whether the required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter is obtainable from a motor-generator of the front end motor-generator system,
if the required amount of vehicle acceleration or deceleration is obtainable from the motor-generator, commanding with the vehicle controller a front end motor-generator controller to control the motor-generator to generate the required amount of vehicle acceleration or deceleration, and
if the required amount of vehicle acceleration or deceleration is not obtainable from the motor-generator, when acceleration is required commanding an engine controller to generate the required amount of vehicle acceleration, and when deceleration is required commanding a braking controller to generate the required amount of vehicle deceleration from a vehicle braking system,
wherein when in the platooning mode, prior to commanding with the front end motor-generator controller the motor-generator to generate vehicle acceleration or deceleration, the vehicle controller determines whether the front end motor-generator system is in an operating state in which a switchable coupling between the motor-generator and a crankshaft of the engine is not to be engaged, and if in said operating state the front end motor-generator controller does not control the motor-generator to generate vehicle acceleration or deceleration.
2. The method of claim 1 , wherein
the at least one predetermined multi-vehicle operating parameter includes at least one of a predetermined vehicle separation distance, a predetermined following time and a predetermined speed.
3. The method of claim 2 , wherein
if the required amount of acceleration or deceleration is not obtainable from the motor-generator, commanding with the front end motor-generator controller the motor-generator to generate an output torque or a regenerative braking torque load corresponding to a portion the required amount of vehicle acceleration or deceleration, respectively.
4. The method of claim 3 , wherein
the portion of the required amount of vehicle acceleration or deceleration the vehicle controller commands the front end motor-generator controller to obtain from the motor-generator corresponds to an upper limit on motor-generator output torque or an upper limit on motor-generator regenerative braking torque load.
5. The method of claim 2 , wherein the vehicle controller includes a platooning controller configured to determine the required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter.
6. The method of claim 5 , wherein
at least two of the vehicle controller, the front end motor-generator controller, the engine controller, and the braking controller are integrated with one another.
7. The method of claim 2 , wherein
when the motor-generator is operated to generate a regenerative braking torque load, electrical energy generated by the motor-generator is stored in a vehicle energy store.
8. The method of claim 7 , wherein
when the vehicle energy store includes at least one of a battery and capacitors.
9. The method of claim 2 , wherein
the vehicle platooning information received from the at least one other vehicle is received at least one of directly from the at least one other vehicle and indirectly via infrastructure.
10. A vehicle configured to operate in a vehicle platoon with at least one other vehicle, comprising:
an internal combustion engine;
a hybrid electric front end motor-generator system;
a braking system;
a vehicle-to-vehicle communications system; and
at least one controller, wherein the at least one controller is programmed to execute a platooning mode operation in which the at least one controller
receives from the vehicle-to-vehicle communications system vehicle platooning information from the at least one other vehicle;
determines whether the vehicle and the at least one other vehicle are operating in a platooning mode in which operation of the vehicle and the at least one other vehicle are coordinated such that at least one predetermined multi-vehicle operating parameter is to be maintained;
if the vehicle is in platooning mode, maintains the at least one predetermined multi-vehicle operating parameter by
determining whether the vehicle is to be accelerated or decelerated to obtain the at least one predetermined multi-vehicle operating parameter,
determining a required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter,
determining whether the required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter is obtainable from a motor-generator of the front end motor-generator system,
if the required amount of vehicle acceleration or deceleration is obtainable from the motor-generator, commanding the motor-generator to generate the required amount of vehicle acceleration or deceleration, and
if the required amount of vehicle acceleration or deceleration is not obtainable from the motor-generator, when acceleration is required commanding an engine controller to generate the required amount of vehicle acceleration, and when deceleration is required commanding a braking system to generate the required amount of vehicle deceleration,
wherein when in the platooning mode, prior to commanding the motor-generator to generate vehicle acceleration or deceleration, the at least one controller determines whether the front end motor-generator system is in an operating state in which a switchable coupling between the motor-generator and a crankshaft of the engine is not to be engaged, and if in said operating state the at least one controller does not control the motor-generator to generate vehicle acceleration or deceleration.
11. The vehicle of claim 10 , wherein
the at least one predetermined multi-vehicle operating parameter includes at least one of a predetermined vehicle separation distance, a predetermined following time and a predetermined speed.
12. The vehicle of claim 11 , wherein
if the required amount of acceleration or deceleration is not obtainable from the motor-generator, the at least one controller is further programmed to command the motor-generator to generate an output torque or a regenerative braking torque load corresponding to a portion the required amount of vehicle acceleration or deceleration, respectively.
13. The vehicle of claim 12 , wherein the portion of the required amount of vehicle acceleration or deceleration the at least one controller commands a front end motor-generator controller to obtain from the motor-generator corresponds to an upper limit on motor-generator output torque or an upper limit on motor-generator regenerative braking torque load.
14. The vehicle of claim 11 , wherein
the hybrid electric front end motor-generator system includes a vehicle energy store, and
when the motor-generator is operated to generate a regenerative braking torque load, electrical energy generated by the motor-generator is stored in the vehicle energy store.
15. The vehicle of claim 11 , wherein
the vehicle platooning information received from the at least one other vehicle is received at least one of directly from the at least one other vehicle and indirectly via infrastructure.
16. A vehicle platooning control system, comprising:
at least one controller, programmed to execute a platooning mode operation of a vehicle in which the at least one controller
receives from a vehicle-to-vehicle communications system vehicle platooning information from at least one other vehicle;
determines whether the vehicle and the at least one other vehicle are operating in a platooning mode in which operation of the vehicle and the at least one other vehicle are coordinated such that at least one predetermined multi-vehicle operating parameter is to be maintained,
if the vehicle is in platooning mode, maintains the at least one predetermined multi-vehicle operating parameter by
determining whether the vehicle is to be accelerated or decelerated to obtain the at least one predetermined multi-vehicle operating parameter,
determining a required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter,
determining whether the required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter is obtainable from a motor-generator of a front end motor-generator system of the vehicle,
if the required amount of vehicle acceleration or deceleration is obtainable from the motor-generator, commanding the motor-generator to generate the required amount of vehicle acceleration or deceleration, and
if the required amount of vehicle acceleration or deceleration is not obtainable from the motor-generator, when acceleration is required commanding an engine of the vehicle to generate the required amount of vehicle acceleration, and when deceleration is required commanding a braking system of the vehicle to generate the required amount of vehicle deceleration,
wherein when in the platooning mode, prior to commanding the motor-generator to generate vehicle acceleration or deceleration, the at least one controller determines whether the front end motor-generator system is in an operating state in which a switchable coupling between the motor-generator and a crankshaft of the engine is not to be engaged, and if in said operating state the at least one controller does not control the motor-generator to generate vehicle acceleration or deceleration.
17. The vehicle platooning control system of claim 15 , wherein
the at least one predetermined multi-vehicle operating parameter includes at least one of a predetermined vehicle separation distance, a predetermined following time and a predetermined speed.
18. The vehicle platooning control system of claim 16 , wherein
the vehicle platooning information received from the at least one other vehicle is received at least one of directly from the at least one other vehicle and indirectly via infrastructure.
19. A method of operating a vehicle having an internal combustion engine and a hybrid electric system configured to at least one of selectively apply torque to and receive torque from a drivetrain of the vehicle, comprising the acts of:
receiving, at a wireless transceiver of the vehicle, vehicle platooning information from at least one other vehicle;
determining with a vehicle controller whether the vehicle and the at least one other vehicle are operating in a platooning mode in which operation of the vehicle and the at least one other vehicle are coordinated such that at least one predetermined multi-vehicle operating parameter is maintained;
if the vehicle is in platooning mode, maintaining the at least one predetermined multi-vehicle operating parameter by
determining with the vehicle controller whether the vehicle is to be accelerated or decelerated to maintain the at least one predetermined multi-vehicle operating parameter,
determining with the vehicle controller a required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter,
determining with the vehicle controller whether the required amount of vehicle acceleration or deceleration needed to obtain the at least one predetermined multi-vehicle operating parameter is obtainable from the hybrid electric system,
if the required amount of vehicle acceleration or deceleration is obtainable from the hybrid electric system, commanding the hybrid electric system to generate the required amount of vehicle acceleration or deceleration, and
if the required amount of vehicle acceleration or deceleration is not obtainable from the hybrid electric system, when acceleration is required commanding an engine controller to generate the required amount of vehicle acceleration, and when deceleration is required commanding a braking controller to generate the required amount of vehicle deceleration from a vehicle braking system,
wherein when in the platooning mode, prior to commanding the hybrid electric system to generate vehicle acceleration or deceleration, the vehicle controller determines whether the hybrid electric system is in an operating state in which a switchable coupling between the hybrid electric system and a crankshaft of the engine is not to be engaged, and if in said operating state the hybrid electric system is not controlled to generate vehicle acceleration or deceleration.