Pumped capacitive storage system

• US 6,169,389 B1
• Filed: 04/05/1999
• Issued: 01/02/2001
• Est. Priority Date: 04/05/1999
• Status: Expired due to Term

• Current Assignee: Tellabs Bedford, Inc. (Infinera Corp.)
• Original Assignee: Marconi Communications, Inc. (Marconi Holdings Company Limited)
• Inventors: Chen, William I. H.
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/286,055
• Time in Patent Office: 638 Days
• Field of Search: 320/166, 320/167, 320/141, 320/140, 363/59, 363/60, 363/71
• US Class Current: 320/166
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence

Abstract

An energy storage system is provided that includes input terminals for receiving input energy from a remote power source and an energy storage device coupled to the input terminals. The energy storage device is operative to store at least of portion of the input energy and to supply stored energy to the input terminals. A pump device is also coupled to the input terminal and to the storage device. The pump device is operative to cause the energy storage device to store at least a portion of the input energy when the input energy level is above a first threshold level, and to cause the energy storage device to supply energy to the input terminals when the input energy level is below a second threshold level. The energy storage system is optionally provided with a current limiter for added protection against short circuits. In one embodiment, the current limiter is bi-direction; it protects against short circuits originating at both the power source and within the energy storage system. Also, the energy storage system is optionally provided with a safety discharge circuit that discharges the energy storage system upon its removal from the energy storage system.

Claims

1. A remotely powered device comprising:

(a) input terminals for receiving available input power from a remote power source;

(b) a load element coupled to said input terminals, said load element consuming at least a portion of said available input power received by said input terminals and generating a load power demand;

(c) an input capacitive device coupled to said input terminals for providing transient bypass for said remote device;

(d) an energy storage device coupled to said input terminals, said energy storage device being configured to store at least a portion of said input power and to supply stored energy to said input terminals; and

(e) a pump device coupled to said input terminals and to said energy storage device, said pump device being operative to cause said energy storage device to store at least a portion of said input power when said input power level is above a first threshold level, and to cause said energy storage device to supply energy to said input terminals when said input power level is below a second threshold level.

2. The device according to claim 1 wherein said input power level is greater than said first power threshold level when said available input power is greater than the load power demands, and said input power level is less than said second power threshold level when said available input power is less than the load power demands.

3. The device according to claim 1 wherein said input power level is a voltage level.

4. The device according to claim 1 wherein said input power level is a current level.

5. The device according to claim 1 wherein said pump device causes said energy storage device to store energy at a voltage level higher than the voltage level of the input energy level.

6. The device according to claim 1 wherein said pump device pumps energy from said input terminals into said storage device.

7. The device according to claim 6 further comprising a controller operatively coupled to said pump device, said controller including voltage measuring circuit for measuring the voltage level at said input and said storage element, said controller being responsive to said measured voltage levels and causing said pump device to cease pumping energy into said storage device.

8. The device according to claim 7 wherein said controller comprises:

(1) a first voltage divider network coupled across said input terminal;

(2) a second voltage divider coupled across said storage device; and

(3) a comparator circuit for providing control signals in response to said voltage levels provided by said voltage divider networks.

9. The device according to claim 1 wherein said pump includes a plurality of switches.

10. The device according to claim 9 wherein said switches comprise FET devices.

11. The device according to claim 9 wherein said switches comprise BJT devices.

12. The device according to claim 1 wherein said pump is arranged in a boost power converter configuration when said storage element stores energy and a buck power converter configuration when said storage element supplies energy.

13. The device according to claim 1 further comprising a current limiter coupled between said input terminals and said pump device and a safety discharge circuit coupled to said energy storage device.

14. The device according to claim 13 wherein said current limiter is a bi-directional current limiter.

15. The device according to claim 1 wherein said first threshold level equals said second threshold level.

16. The device according to claim 1 wherein said pump is a bi-directional pump.

17. The device according to claim 1 wherein said pump is a bi-directional power converter.

18. A remotely powered system comprising:

(a) a power source;

(b) transmission wires coupled to said power source for transmitting energy from said power source to a remotely powered device; and

(c) said remotely powered device comprising;

(1) input terminals for receiving available input power from a remote power source;

(2) a load element coupled to said input terminals, said load element consuming at least a portion of said available input power received by said input terminals and generating a load power demand;

(3) an input capacitive device coupled to said input terminals for providing transient bypass for said remote device;

(4) an energy storage device coupled to said input terminals, said energy storage device being configured to store at least a portion of said input power and to supply stored energy to said input terminals; and

(5) a pump device coupled to said input terminals and to said energy storage device, said pump device being operative to cause said energy storage device to store at least a portion of said input power when said input power level is above a first threshold level, and to cause said energy storage device to supply energy to said input terminals when said input power level is below a second threshold level.

19. A power supply for a remotely powered device comprising:

(a) input terminals for receiving available input power from a remote power source;

(b) a power converter coupled to said input terminals, said power converter consuming at least a portion of said available input power received by said input terminals and generating a load power demand;

(c) an input capacitive device coupled to said input terminals for providing transient bypass for said remote device;

(d) an energy storage device coupled to said input terminals, said energy storage device being configured to store at least a portion of said available input power and to supply stored energy to said input terminals; and

(e) a pump device coupled to said input terminals and to said energy storage device, said pump device being operative to cause said energy storage device to store at least a portion of said input power when said input power level is above a first threshold level, and to cause said energy storage device to supply energy to said input terminals when said input power level is below a second threshold level.

20. A method of providing power to a device located remotely from a power source comprising the steps of:

(a) providing power to said remote device at an input;

(b) storing at least a portion of said power at a voltage level higher than the voltage level at said input when said voltage level at said input is higher than a first threshold level; and

(c) supplying energy to said input when the voltage level at said input falls below a second threshold level.

21. A method of providing power to a device located remotely from a power source comprising the steps of:

(a) providing power to said remote device at an input;

(b) storing at least a portion of said power at a voltage level higher than the voltage level at said input when said power available at said input is greater than the power demanded by said remote device; and

(c) supplying energy to said input when said power available at said input is less than the power demanded by said remote device.

22. A remotely powered device comprising:

(a) input terminals means for receiving input energy from a remote power source;

(b) load means for consuming input energy received by said input terminals;

(c) energy storage means for storing at least of portion of said input energy and for supplying said stored energy to said input terminals; and

(d) pump means for causing said energy storage means to store at least a portion of the input energy when said input energy level is above a first threshold level and for causing said energy storage device to supply energy to said input terminals when said input energy level is below a second threshold level.

23. A remotely powered device comprising:

(a) input terminals for receiving available input power from a remote power source;

(b) a load element coupled to said input terminals, said load element consuming at least a portion of said available input power received by said input terminals and generating a load power demand;

(c) an input capacitive device coupled to said input terminals for providing transient bypass for said remote device;

(d) an energy storage device coupled to said input terminals, said energy storage device being configured to store at least a portion of said available input power and to supply stored energy to said input terminals; and

(e) a pump device coupled to said input terminals and to said energy storage device, said pump device being operative to cause said energy storage device to store at least a portion of said available input power when said available input power is greater than said load power demands, and to cause said energy storage device to supply energy to said input terminals when said available input power is less than said load power demands.

24. A remotely powered device comprising:

(a) input terminals for receiving available input power from a remote power source;

(b) a load element coupled to said input terminals, said load element consuming at least a portion of said available input power received by said input terminals and generating a load power demand;

(c) an input capacitive device coupled to said input terminals for providing transient bypass for said remote device;

(d) an energy storage device coupled to said input terminals, said energy storage device being configured to store at least a portion of said input power and to supply stored energy to said input terminals;

(e) an input power detector coupled to said input terminals for measuring an input power characteristic;

(f) a load power detector coupled to said load element for measuring a load power demand characteristic

(g) a decision unit coupled to said input power detector and said output power detector, said decision unit providing an output in response to signals from said input power detector and said load power detector, said output signal providing a store indication signal when said energy storage device should store energy and providing a supply indication signal when said energy storage device should supply energy; and

(h) a pump device coupled to said input terminals, said energy storage device and said decision unit, said pump device being operative to cause said energy storage device to store at least a portion of said input power in response to said store indication signal and being operative to cause said energy storage device to supply energy to said input terminals in response to said supply indication signal.

25. The device according to claim 24 wherein said input power detector, load power detector, and said decision unit are external to said pump device.