Hybrid electric vehicle and method of control thereof

Patent metadata

Field	Value
Publication number	US-9315189-B2
Application number	US-201314374364-A
Country	US
Kind code	B2
Filing date	Jan 24, 2013
Priority date	Jan 25, 2012
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

A hybrid electric vehicle ( 100 ) comprising: a fuel powered engine ( 121 ) and electric motor means ( 123 ) operable to provide torque to drive the vehicle ( 100 ); energy storage means ( 150 ) operable to store electrical energy generated by generator means ( 123 ) for driving the electric motor means ( 123 ); and energy management means ( 140 ) for controlling the engine ( 121 ) and electric motor means ( 123 ) to provide torque to drive the vehicle and for controlling the generator means to generate electrical energy for storage in the energy storage means, wherein the vehicle comprises control means operable to monitor a value of one or more parameters associated with the vehicle, the control means being arranged automatically to identify a current driving style of a driver ranging from an economy-oriented driving style to a performance-oriented driving style responsive to the value of the one or more parameters, the energy management means being operable to control the engine, electric motor means and generator means responsive to the driving style of the user.

First claim

The invention claimed is:

1. A controller for a hybrid electric vehicle having a powertrain comprising an engine and at least one electric machine, at least one of said at least one electric machine being operable as a propulsion motor to provide drive torque to drive the vehicle, and an energy storage device that powers the at least one electric machine as a propulsion motor,
the controller being configured to control the engine and the at least one electric machine to provide torque to drive the vehicle in a hybrid vehicle (HV) mode in which the engine is switched on or an electric vehicle (EV) mode in which the engine is switched off, the controller being further configured to:
monitor a value of one or more parameters associated with the vehicle;
identify a current driving style of a driver in dependence on the value of the one or more parameters;
calculate a value of a driver behaviour index in dependence on the driving style of the driver;
control the powertrain to operate in the HV or EV modes in dependence on the driving style of the driver;
control at least one of said at least one electric machines to operate as a generator to generate electrical energy for storage in the energy storage device;
control the powertrain to operate in a torque boost mode of operation in which at least one of said at least one electric machine operates as a propulsion motor to provide drive torque to drive the vehicle in parallel with the engine;
control the engine and the at least one electric machine in dependence on the value of the driver behaviour index thereby to prevent the amount of energy stored in the energy storage device from falling to a value preventing assumption of the torque boost mode; and
prevent the value of the driver behaviour index changing in response to a value of longitudinal acceleration, when a value of lateral acceleration exceeds a prescribed value.

2. The controller of claim 1 , wherein the driving style ranges from an economy-oriented driving style to a performance-oriented driving style.

3. The controller of claim 1 , wherein the one or more parameters monitored by the controller comprise at least one selected from amongst:
(a) a speed of rotation of the engine;
(b) a speed of rotation of the electric motor machine;
(c) a speed of the vehicle;
(d) a longitudinal acceleration of the vehicle;
(e) a lateral acceleration of the vehicle;
(f) an accelerator pedal position;
(g) a state of an accelerator pedal kick-down detector;
(h) a brake pedal position;
(i) a gear ratio between the engine or the at least one electric machine operable as the propulsion motor and one or more wheels of the vehicle;
(j) a proportion of an amount of a brake torque requested by the driver that is provided by regenerative braking;
(k) an amount of energy stored in the energy storage device;
(l) a speed of at least one portion of a driveline of the vehicle; and
(m) an amount of positive drive torque.

4. The controller of claim 1 , configured to change the value of the driver behaviour index towards a first value when the driver displays an economy-oriented driving style and to change the value of the driver behaviour index towards a second value when the driver displays a performance-oriented driving style.

5. The controller of claim 4 , arranged to increase a target state of charge of the energy storage device as the value of the driver behaviour index tends towards the second value and to reduce the target state of charge of the energy storage device as the value of the driver behaviour index tends towards the first value.

6. The controller of claim 4 , configured to change the value of the driver behaviour index towards the second value in dependence on a value of longitudinal acceleration of the vehicle.

7. The controller of claim 6 , configured to change the value of the driver behaviour index towards the second value when the value of longitudinal acceleration is more positive than an index increase positive threshold value being a positive acceleration value or is more negative than an index increase negative threshold value being a negative acceleration value.

8. The controller of claim 6 , configured to change the value of driver behaviour index towards the first value when the value of longitudinal acceleration is between an index decrease positive threshold value being a positive value and an index decrease negative threshold value being a negative value.

9. The controller of claim 4 , configured to change the value of the driver behaviour index in dependence on a relative amount of a demanded braking torque that is provided by regenerative braking.

10. The controller of claim 9 , configured to change the value of the driver behaviour index towards the second value when the relative amount of a demanded braking torque that is provided by regenerative braking is below a prescribed amount.

11. The controller of claim 4 , configured to change the value of driver behaviour index responsive to at least one selected from amongst brake pedal pressure, brake pedal position, rate of change of brake pedal pressure and rate of change of brake pedal position.

12. The controller of claim 1 , operable to latch the engine in an on condition in dependence on the driving style of the driver.

13. The controller of claim 12 , operable to provide feedback to the driver as to whether the engine has been latched on because of the driving style of the driver.

14. The controller of claim 2 , operable to provide feedback to the driver in dependence on a result of the determination whether the driving style corresponds to a performance oriented driving style or an economy oriented driving style.

15. The controller of claim 13 , operable to provide feedback via a visual indicator or an audible indicator.

16. A method of controlling a hybrid electric vehicle having a powertrain comprising an engine and at least one electric machine, at least one of said at least one electric machine being operable as a propulsion motor to provide drive torque to drive the vehicle, and an energy storage device that powers the at least one electric machine as a propulsion motor,
the method comprising controlling the engine and at least one electric machine to provide torque to drive the vehicle in a hybrid vehicle (HV) mode in which the engine is switched on or an electric vehicle (EV) mode in which the engine is switched off, the method further comprising:
monitoring a value of one or more parameters associated with the vehicle;
identifying a current driving style of a driver in dependence on the value of the one or more parameters;
calculating a value of a driver behaviour index in dependence on the driving style of the driver;
controlling the powertrain to operate in the HV or EV modes in dependence on the driving style of the driver;
controlling at least one said at least one electric machine to operate as a generator to generate electrical energy for storage in the energy storage device;
controlling the powertrain to operate in a torque boost mode of operation in which at least one said at least one electric machine operates as a propulsion motor to provide drive torque to drive the vehicle in parallel with the engine;
controlling the engine and at least one electric machine in dependence on the value of the driver behaviour index thereby to prevent the amount of energy stored in the energy storage device from falling to a value preventing assumption of the torque boost mode; and
preventing the value of the driver behaviour index changing in response to a value of longitudinal acceleration, when a value

Assignees

• Jaguar Land Rover Ltd

Inventors

• Mould Andy
• Dixon Neil
• Eftychiou Yiannis
• Dextreit Clement
• Lowndes Andi

Classifications

• B60W2510/244

  Charge state · CPC title

• B60W20/10

  Controlling the power contribution of each of the prime movers to meet required power demand · CPC title

• B60W2540/30

  Driving style · CPC title

• B60W2540/103

  Accelerator thresholds, e.g. kickdown · CPC title

• B60W10/08

  including control of electric propulsion units, e.g. motors or generators · CPC title