Diversion of energy from regenerative braking

• US 9,020,674 B2
• Filed: 01/09/2013
• Issued: 04/28/2015
• Est. Priority Date: 04/13/2012
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Gregg, Christopher, Ward, Justin, Kusumi, Hidetoshi
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): Sweeney, Brian P
• Application Number:
  US13/737,869
• Publication Number:
  US 20130274975A1
• Time in Patent Office: 839 Days
• Field of Search: 701/22, 903/903, 903/941, 903/947, 180/65.1, 180/65.27, 180/65.275
• US Class Current: 701/22
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60W 10/196 acting within the driveline, e.g. retarders
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/14 in conjunction with braking regeneration
• CPC Class Codes: B60W 2556/00 Input parameters relating to data
• CPC Class Codes: B60W 30/18127 Regenerative braking
• CPC Class Codes: B60W 30/1886 Controlling power supply to auxiliary devices
• CPC Class Codes: B60Y 2300/92 Battery protection from overload or overcharge
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/947 Characterized by control of braking, e.g. blending of regeneration, friction braking

Abstract

A regenerative braking system for a vehicle utilizing diversion of energy for efficient use or maintaining consistent vehicle performance. The regenerative braking system includes a generator for producing regenerative energy during slowing and includes switches connected to a battery and a plurality of devices. A processor is connected with the battery and the switches for controlling the configuration of the switches based on a characteristic of the battery. If the battery has a state of charge exceeding a predetermined threshold, the processor controls the switches to route the regenerative energy to the other devices. The processor also controls the switches to provide regenerative energy to specific devices where it may most desirably be utilized. Heating and cooling units of the vehicle may be alternatively or simultaneously connected to receive the regenerative energy for providing consistent vehicle slowing performance when the battery state of charge exceeds the predetermined threshold.

Claims

1. A regenerative braking system for a vehicle comprising:

a generator coupled with the vehicle for generating energy during a deceleration of the vehicle;

a battery having a state of charge and switchably coupled with the generator for receiving at least a portion of the energy from the generator;

a first device switchably coupled with the generator for receiving at least a portion of the energy from the generator;

a second device switchably coupled with the generator for receiving at least a portion of the energy from the generator; and

a processor configured to control the switchable coupling of the battery, the first device and the second device with the generator based on the state of charge of the battery or an instantaneous temperature of air in an interior of the vehicle and, when the state of charge of the battery is greater than a predetermined threshold and the instantaneous temperature of air in the interior of the vehicle is equal to a desired temperature of air in the interior of the vehicle, to couple the first device to the generator for a first predetermined amount of time and then couple the second device to the generator for a second predetermined amount of time or to couple the first device and the second device to the generator such that an effect of the first device cancels out an effect of the second device.

2. The regenerative braking system of claim 1 wherein the processor is configured to couple the battery to the generator only when the state of charge of the battery is less than a predetermined threshold.

3. The regenerative braking system of claim 2 wherein the processor is configured to couple the first device to the generator or the second device to the generator when the state of charge of the battery is greater than the predetermined threshold for maintaining a constant deceleration rate for the vehicle.

4. The regenerative braking system of claim 2 wherein the processor is configured to couple the first device to the generator and the second device to the generator when the state of charge of the battery is greater than the predetermined threshold for maintaining a constant deceleration rate for the vehicle.

5. The regenerative braking system of claim 1 wherein the first device is a heater for providing heated air to an interior of the vehicle and the second device is an air conditioning unit for providing cooled air to the interior of the vehicle.

6. The regenerative braking system of claim 5 further comprising a climate control element coupled with the processor for setting a desired temperature of air in the interior of the vehicle.

7. The regenerative braking system of claim 6 wherein the processor is configured to couple the heater to the generator when the desired temperature is greater than an instantaneous temperature of air in the interior of the vehicle.

8. The regenerative braking system of claim 7 wherein the processor is configured to couple the air conditioning unit to the generator when the desired temperature is less than the instantaneous temperature of air in the interior of the vehicle.

9. A system for diverting regenerative energy from a generator of an electric vehicle comprising:

a battery having a state of charge, coupled with the generator through a first switch having a closed configuration and an open configuration and configured to receive regenerative energy from the generator when the first switch is in the closed configuration;

a heater coupled with the generator through a second switch having a closed configuration and an open configuration and configured to receive regenerative energy from the generator when the second switch is in the closed configuration;

an air conditioning unit coupled with the generator through a third switch having a closed configuration and an open configuration and configured to receive regenerative energy from the generator when the third switch is in the closed configuration; and

a processor coupled with the battery, the first switch, the second switch and the third switch and configured to control the first switch, the second switch and the third switch such that when the state of charge of the battery is greater than a predetermined threshold and an instantaneous temperature of the air in the interior of the vehicle is equal to a desired temperature the interior of the vehicle, the processor controls the first switch to be in the open configuration, the second switch to be in the closed configuration and the third switch to be in the open configuration for a first predetermined amount of time and controls the first switch to be in the open configuration, the second switch to be in the open configuration, and the third switch to be in the closed configuration for a second predetermined amount of time or the processor controls the first switch to he in the open configuration, the second s itch to be in the closed configuration and the third switch to be in the closed configuration such that an effect of the heater cancels out an effect of the air conditioning unit.

10. The system of claim 9 further comprising a temperature sensor coupled to the processor and configured to sense the instantaneous temperature of the air in the interior of the vehicle.

11. The system of claim 10 further comprising a user control coupled to the processor, the user control configured to set a desired temperature for air in the cabin of the vehicle.

12. The system of claim 11 wherein the processor is configured to control the first switch to the closed configuration, the second switch to the closed configuration and the third switch to the open configuration when the temperature of air sensed by the temperature sensor is less than the desired temperature and the state of charge of the battery is less than the predetermined threshold.

13. The system of claim 12 wherein the processor is configured to control the first switch to the closed configuration, the second switch to the open configuration and the third switch to the closed configuration when the temperature of air sensed by the temperature sensor is greater than the desired temperature and the state of charge of the battery is less than the predetermined threshold.

14. A method of diverting energy in a regenerative braking system for an electric vehicle, the method comprising the steps of:

providing a battery, a generator, a heater and an air conditioning unit coupled with the electric vehicle;

determining if the battery has a state of charge greater than a predetermined threshold;

determining a desired temperature within a cabin of the electric vehicle;

determining an instantaneous temperature within the cabin of the electric vehicle; and

coupling the heater to the generator for a first predetermined amount of time and then coupling the air conditioning unit to the generator for a second predetermined amount of time or coupling the heater and the air conditioning unit to the generator such that an effect of the heater cancels out an effect of the air conditioning unit when the state of charge of the battery is greater than the predetermined threshold and when the instantaneous temperature is equal to the desired temperature.

15. The method of claim 14 wherein the step of coupling the heater to the generator for a first predetermined amount of time and then coupling the air conditioning unit to the generator for a second predetermined amount of time or coupling the heater and the air conditioning unit to the generator maintains a constant deceleration rate for the electric vehicle.

16. The method of claim 14 further comprising the step of transmitting all of the energy to the battery of the electric vehicle when the state of charge of the battery is less than the predetermined threshold.

17. The method of claim 14 further comprising the steps of:

transmitting at least a portion of the energy to the heater when the instantaneous temperature is less than the desired temperature; and

transmitting at least a portion of the energy to the air conditioning unit when the instantaneous temperature is greater than the desired temperature.