Rapid charger for ultracapacitors

• US 7,170,260 B2
• Filed: 06/30/2003
• Issued: 01/30/2007
• Est. Priority Date: 06/30/2003
• Status: Expired due to Fees

• Current Assignee: Tesla Inc.
• Original Assignee: Maxwell Technologies Incorporated (Tesla Inc.)
• Inventors: Thrap, Guy C.
• Primary Examiner(s): Tso; Edward H.
• Application Number:
  US10/611,420
• Publication Number:
  US 20040263129A1
• Time in Patent Office: 1,310 Days
• Field of Search: 320/167, 320/166, 320/139, 320/140, 320/141, 320/148, 320/128, 320/129, 320/145, 320/1, 320/20, 320/39, 320/44, 323/282, 323/285, 323/222, 323/271, 323/290
• US Class Current: 320/166
• CPC Class Codes: H02J 2207/50 Charging of capacitors, supercapacitors, ultra-capacitors or double layer capacitors using capacitors as storage or buffering device in cooperation with batteries H02J7/345
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices

Abstract

A rapid charging circuit for charging a power module is disclosed. The power module includes one or more ultracapacitors. The power module is charged using an energy source connected to the power module. The charging circuit includes a control circuit adapted to maintain a constant power level at the power module during charging as the voltage level across the power module increases. The control circuit includes a pulse-width modulator and an inductor connected in series with the power module. The pulse-width modulator can control a charge level of the inductor. The charge level may correspond to a current level which is in accordance with a desired power level at the power module and an instantaneous voltage level across the power module. The inductor may be adapted to limit a current level through the power module to a predetermined peak level. The control circuit may be adapted to provide a current level through the power module greater than a current level from said energy source during at least a portion of a charging period.

Claims

1. An arrangement for charging a power module, comprising:

a power module including one or more ultracapacitors;

an energy source connected to said power module, a positive terminal of said energy source connected to a positive terminal of said power module, and a negative terminal of said energy source connected to a negative terminal of said power module; and

a control circuit adapted to provide a current level to said power module greater than a current level from said energy source during at least a portion of a charging period, wherein said control circuit is adapted to maintain a constant power level at the power module during at least a portion of the charging period as a voltage level across the power module increases.

2. The arrangement according to claim 1, wherein said control circuit includes pulse-width modulator and an inductor connected in series with said power module.

3. The arrangement according to claim 2, wherein said pulse-width modulator controls a charge level of said inductor.

4. The arrangement according to claim 3, wherein said charge level corresponds to a current level which is in accordance with a desired power level at said power module and an instantaneous voltage level across said power module.

5. The arrangement according to claim 2, wherein said inductor is adapted to limit a current level through said power module to a predetermined peak level.

6. A constant-power charging circuit for an ultracapacitor power module, comprising:

a pulse-width modulator; and

an inductor connected in series with said pulse-width modulator and said power module;

wherein said pulse-width modulator is adapted to control the charge level of said inductor, and wherein a control circuit is adapted to provide a current level through said power module greater than a current level from an energy source during at least a portion of a charging period.

7. The circuit according to claim 6, wherein said charge level corresponds to a current level which is in accordance with a desired power level at said power module and an instantaneous voltage level across said power module.

8. The arrangement according to claim 6, wherein said inductor is adapted to limit a current level through said power module to a predetermined peak level.

9. The arrangement according to claim 6, wherein said control circuit is adapted to provide a current level through said power module greater than a current level from said energy source during at least a portion of a charging period.

10. A method of charging an ultracapacitor power module, comprising:

charging an inductor connected in series between an energy source and said power module; and

controlling a charge level of said inductor to achieve a desired current level through said power module, said desired current level through said power module being greater than a current level from said energy source during at least a portion of a charging period, wherein a power level to said power module is kept constant during at least a portion of a charging period of said power module.

11. The method according to claim 10, wherein said controlling includes modulating the current from said energy source to said inductor through a pulse-width modulator.

12. The method according to claim 10, wherein said desired current level corresponds to a desired power level at said power module.