OPERATION OF A RANGE EXTENDED ELECTRIC VEHICLE

• US 20100211242A1
• Filed: 09/26/2008
• Published: 08/19/2010
• Est. Priority Date: 09/26/2007
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Kohn, Scott Ira, Straubel, Jeffrey Brian, Hermann, Weston Arthur, Kelty, Kurt Russell
• Granted Patent: US 8,346,419 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 50/62 charged by low-power generators primarily intended to support the batteries, e.g. range extenders
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/28 including control of fuel cells
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2510/24 Energy storage means
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor

Abstract

One embodiment includes a method that includes monitoring a battery state of charge circuit that is coupled to a vehicle battery, calculating an averaged value of the state of charge over a time period, charging the vehicle battery by powering a generator with a fuel burning engine that powered on and powered off according to one of a first operational mode and a second operational mode, wherein in the first operational mode the engine is powered on when the battery state of charge drops below a first state of charge and continues until the averaged value of the state of charge increases to a first preprogrammed value.

Claims

1. A system, comprising:

a motor to propel an electric vehicle;

a battery to power the motor;

a fuel burning engine to charge the battery;

an engine controller circuit to power on the fuel burning engine when it receives an engine control signal;

a state of charge circuit preprogrammed to operate according to a selected one of a first operational mode and a second operational mode, the state of charge circuit to monitor a battery state of charge and to calculate an averaged value over a time period,

the state of charge circuit in the first operational mode to provide the engine control signal when the battery state of charge is below a first state of charge and until the averaged value increases to a first preprogrammed value,

the state of charge circuit in the second operational mode to provide the engine control signal when the state of charge reaches a second state of charge, lower than the first state of charge, and to provide the engine control signal until the averaged value increases to a second preprogrammed value other than the first preprogrammed value; and

a user interface coupled to the state of charge circuit to receive a user command to select an operational mode for the state of charge circuit.

2. The system of claim 1, wherein the state of charge circuit is preprogrammed to begin the time period after the engine control signal is provided and a preprogrammed battery state of charge is reached.

3. The system of claim 1, wherein the state of charge circuit is to calculate the averaged value only after the battery state of charge has reached a preprogrammed battery state of charge.

4. The system of claim 1, wherein the state of charge circuit is further preprogrammed with a third operational mode to provide the engine control signal when the battery state of charge is below a third state of charge and continues until a user selected target state of charge is reached.

5. The system of claim 4, wherein the first state of charge is approximately 70% of a full battery state of charge.

6. The system of claim 5, wherein the second state of charge is approximately 50% of the full battery state of charge.

7. The system of claim 6, wherein the third state of charge is approximately 20% of the full battery state of charge.

8. A method, comprising:

monitoring a battery state of charge circuit that is coupled to a vehicle battery;

calculating an averaged value of the state of charge over a time period;

charging the vehicle battery by powering a generator with a fuel burning engine that powered on and powered off according to one of a first operational mode and a second operational mode, wherein

in the first operational mode the engine is powered on when the battery state of charge drops below a first state of charge and continues until the averaged value of the state of charge increases to a first preprogrammed value; and

in the second operational the engine is powered on when the battery state of charge drops below a second state of charge, lower than the first state of charge, and continues until the averaged value of the state of charge increases to a second preprogrammed value lower than the first preprogrammed value; and

receiving a user command to select between the first operational mode and the second operational mode.

9. The method of claim 8, wherein the first preprogrammed value is approximately 50% of a full battery state of charge.

10. The method of claim 9, wherein the second preprogrammed value is approximately 20% of a full battery state of charge.

11. The method of claim 8, wherein the first preprogrammed value is approximately 70% of a full battery state of charge.

12. The method of claim 8, wherein calculating the averaged value occurs only after the battery state of charge has reached a preprogrammed battery state of charge.

13. A system, comprising:

a motor to propel an electric vehicle;

a battery to power the motor;

a fuel burning engine to charge the battery;

an engine controller circuit to power on the fuel burning engine when it receives an engine control signal;

a state of charge circuit to monitor a battery state of charge and preprogrammed to operate according to a selected one of a first operational mode and a second operational mode, wherein

the state of charge circuit in the first operational mode is to provide the engine control signal when the battery state of charge is below a first state of charge and until the battery state of charge reaches a second state of charge, and

the state of charge circuit in the second operational mode is to provide the engine control signal when the state of charge is below a third state of charge lower than the first state of charge and the second state of charge and until the battery state of charge reaches a second state of charge reaches a fourth state of charge that is higher than the third state of charge and lower than the first state of charge and the second state of charge; and

a user interface coupled to the state of charge circuit to receive a user command to select an operational mode for the state of charge circuit.

14. The system of claim 13, wherein in the second operational mode, after the third state of charge has been reached once, the state of charge circuit provides the engine control signal when the battery state of charge drops below a fifth state of charge that is between the third and fourth states of charge.

15. The system of claim 14, wherein the state of charge circuit is to calculate an averaged value over a time period and is preprogrammed to begin the time period after the engine control signal is provided and a preprogrammed battery state of charge is reached.

16. The system of claim 15, wherein the difference between the third state of charge and the averaged value is greater than the difference between the fifth state of charge and the averaged value.

17. The system of claim 14, wherein a difference between the third state of charge and the fifth state of charge is greater than a difference between the third state of charge and the fourth state of charge.

18. The system of claim 17, wherein the difference between the third state of charge and the fifth state of charge is twice as great as the difference between the third state of charge and the fourth state of charge.

19. The system of claim 14, wherein a difference between the third state of charge and the fifth state of charge is less than a difference between the third state of charge and the fourth state of charge.

20. The system of claim 14, wherein the third state of charge is approximately 10%, the fourth state of charge is approximately 23%, the fifth state of charge is approximately 17%.