Bi-directional battery voltage converter

• US 9,199,543 B2
• Filed: 07/29/2010
• Issued: 12/01/2015
• Est. Priority Date: 07/31/2009
• Status: Active Grant

• Current Assignee: Thermo King Corporation (Trane Technologies plc)
• Original Assignee: Thermo King Corporation (Trane Technologies plc)
• Inventors: Brabec, Ladislaus Joseph
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): Chung, Steve T
• Application Number:
  US12/845,838
• Publication Number:
  US 20110025126A1
• Time in Patent Office: 1,951 Days
• Field of Search: 320/103, 320/104, 320/110, 320/117, 320/119, 320/122, 320/123, 180/65.1, 180/65.21, 180/65.22, 180/65.225, 180/65.23, 180/65.24, 180/65.275, 180/65.28, 180/65.31, 180/65.51, 180/65.8, 307/149, 903/902, 903/907, 903/914
• US Class Current: 1/1
• CPC Class Codes: B60L 53/00 Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
• CPC Class Codes: B60L 53/51 Photovoltaic means
• CPC Class Codes: B60L 53/52 Wind-driven generators
• CPC Class Codes: B60L 53/54 Fuel cells
• CPC Class Codes: B60L 53/57 Charging stations without connection to power networks
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/0032 disconnection of loads if battery is not under charge, e.g. in vehicle if engine is not running
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel
• 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 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A method of charging batteries in a vehicle electrical system having a system bus, a first switch selectively connecting a first battery with the system bus, a second switch selectively connecting a second battery with the system bus, and a controller monitoring a voltage of the vehicle electrical system and controllably opening and closing the first switch and the second switch. The method includes closing the first switch and opening the first switch if the voltage of the vehicle electrical system traverses a threshold value. The method also includes closing the second switch and opening the second switch if the voltage of the vehicle electrical system traverses the threshold value.

Claims

1. A method of charging batteries in a vehicle electrical system, the vehicle electrical system comprising a system bus, a first switch selectively connecting a first battery with the system bus, a second switch selectively connecting a second battery with the system bus, and a controller monitoring a voltage of the vehicle electrical system and controllably opening and closing the first switch and the second switch, the method comprising:

a) opening the first switch and the second switch until the first switch and the second switch are open at the same time, thereby disconnecting the first battery and the second battery from the system bus;

b) closing the first switch, thereby connecting the first battery with the system bus;

c) monitoring the voltage of the vehicle electrical system in transient response to the first switch closing;

d) opening the first switch if the voltage of the vehicle electrical system traverses a threshold value in transient response to the first switch closing;

e) closing the second switch, thereby connecting the second battery with the system bus;

f) monitoring the voltage of the vehicle electrical system in transient response to the second switch closing; and

g) opening the second switch if the voltage of the vehicle electrical system traverses the threshold value in transient response to the second switch closing; and

repeating the steps of b, c, d, e, f, and g until the first switch and second switch remain closed.

2. The method of claim 1, wherein at least one of the first switch and the second switch is an electronic switch.

3. The method of claim 2, wherein the electronic switch includes a bi-directional voltage converter.

4. The method of claim 3, wherein the bi-directional voltage converter includes an inductive H-bridge circuit.

5. The method of claim 1, wherein the threshold value is based upon a voltage difference from a starting value.

6. The method of claim 1, wherein the threshold value is based upon a voltage difference from a nominal value.

7. The method of claim 1, wherein the threshold value is based on a ratio of the voltage of the vehicle electrical system to a starting voltage.

8. The method of claim 1, wherein the threshold value is based on a ratio of the voltage of the vehicle electrical system to a nominal value.

9. A controller for use with a vehicle electrical system, the controller comprising a voltage input terminal, a memory, and a micro-processor, the controller

controllably opening a first switch and a second switch until the first switch and the second switch are open at the same time, thereby disconnecting a first battery and a second battery from a system bus,

controllably closing the first switch, thereby connecting the first battery with the system bus,

receiving a voltage of the vehicle electrical system at the voltage input terminal in transient response to the first switch closing,

comparing, in the micro-processor, a value related to the voltage of the vehicle electrical system to a threshold value from the memory,

controllably opening the first switch in transient response to the voltage of the vehicle electrical system traversing the threshold value,

controllably closing the second switch, thereby connecting a second battery with the system bus,

receiving a voltage of the vehicle electrical system at the voltage input terminal in transient response to the second switch closing,

comparing, in the micro-processor, a value related to the voltage of the vehicle electrical system to the threshold value, and

controllably opening the second switch in transient response to the voltage of the vehicle electrical system traversing the threshold value,

wherein the controller continues

controllably closing the first switch, thereby connecting the first battery with the system bus,

receiving the voltage of the vehicle electrical system at the voltage input terminal in transient response to the first switch closing,

comparing, in the micro-processor, the value related to the voltage of the vehicle electrical system to the threshold value from the memory,

controllably opening the first switch in transient response to the voltage of the vehicle electrical system traversing the threshold value,

controllably closing the second switch, thereby connecting the second battery with the system bus,

receiving the voltage of the vehicle electrical system at the voltage input terminal in transient response to the second switch closing,

comparing, in the micro-processor, the value related to the voltage of the vehicle electrical system to the threshold value, and

controllably opening the second switch in transient response to the voltage of the vehicle electrical system traversing the threshold value until the first switch and the second switch remain closed.

10. A vehicle electrical system comprising;

a system bus;

a first battery;

a first switch selectively connecting the first battery to the system bus;

a second battery;

a second switch selectively connecting the second battery to the electrical system; and

a controller

controllably opening the first switch and the second switch until the first switch and the second switch are both open at the same time, thereby disconnecting the first battery and the second battery from the system bus,

controllably closing the first switch, thereby connecting the first battery with the system bus,

monitoring a voltage of the vehicle electrical system in transient response to the first switch closing,

controllably opening the first switch if the voltage of the vehicle electrical system traverses a threshold value in transient response to the first switch closing,

controllably closing the second switch, thereby connecting a second battery associated with the second switch with the system bus,

monitoring the voltage of the vehicle electrical system in transient response to the second switch closing, and

opening the second switch if the voltage of the vehicle electrical system traverses the threshold value in transient response to the second switch closing,

wherein the controller continues

controllably closing the first switch, thereby connecting the first battery with the system bus,

monitoring the voltage of the vehicle electrical system in transient response to the first switch closing,

controllably opening the first switch if the voltage of the vehicle electrical system traverses the threshold value in transient response to the first switch closing,

controllably closing the second switch, thereby connecting the second battery associated with the second switch with the system bus,

monitoring the voltage of the vehicle electrical system in transient response to the second switch closing, and

opening the second switch if the voltage of the vehicle electrical system traverses the threshold value in transient response to the second switch closing, until the first switch and second switch remain closed.

11. The vehicle electrical system of claim 10, wherein the first switch is a bi-directional voltage converter.

12. The vehicle electrical system of claim 11, wherein the bi-directional voltage converter includes an inductive H-bridge circuit.

13. The method of claim 10, wherein the threshold value is based upon a voltage difference from a starting value.

14. The method of claim 10, wherein the threshold value is based upon a voltage difference from a nominal value.

15. The method of claim 10, wherein the threshold value is based on a ratio of the voltage of the vehicle electrical system to a starting voltage.

16. The method of claim 10, wherein the threshold value is based on a ratio of the voltage of the vehicle electrical system to a nominal value.