Ultra-wide input range power supply for circuit protection devices

• US 6,577,485 B2
• Filed: 10/12/2001
• Issued: 06/10/2003
• Est. Priority Date: 10/12/2001
• Status: Active Grant

• Current Assignee: Square D Company (Schneider Electric SE)
• Original Assignee: Square D Company (Schneider Electric SE)
• Inventors: Meehleder, Steven M., Reid, Paul A.
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US09/976,706
• Publication Number:
  US 20030072115A1
• Time in Patent Office: 606 Days
• Field of Search: 363/49, 363/69, 363/70, 363/89, 323/901, 323/908, 361/18, 361/93.1, 361/93.9, 307/66
• US Class Current: 361/93.1
• CPC Class Codes: H02H 1/066 and comprising a shunt regulator

Abstract

A wide input range power supply for a circuit protection and/or fault detector device includes a passive supply for providing power to a load under nominal input voltage conditions at or near the nominal line voltage with minimum power loss, and a linear regulating supply path for assisting the passive supply at an input line voltage substantially below the nominal line voltage value.

Claims

1. A wide input range power supply for a circuit protection and/or fault detector device, said power supply comprising:

a passive supply path comprising a passive supply for providing power to a load under nominal input line voltage conditions at or near the nominal line voltage with minimum power loss; and

a linear regulating supply path including a linear supply for supplying power to said load during start-up and at input line voltages below a first value, and for assisting the passive supply at input line voltages substantially below the nominal line voltage value and above said first value.

2. The power supply of claim 1 wherein said passive supply comprises first circuit elements for reducing the supply voltage reactively, second circuit elements for eliminating surge current in response to high frequency pulses on the supply input, and a bridge rectifier.

3. The power supply of claim 1 wherein said linear regulating supply path comprises a circuit for monitoring the voltage level at an output capacitor;

and a switching circuit, responsive to said circuit for montoring the voltage level, for supplying current.

4. The power supply of claim 3 wherein said circuit for monitoring the voltage level and supplying current comprises a zener diode and wherein said switching circuit comprises a power-supplying transistor and a first switching transistor for switching said power-supplying transistor into a conductive state for conducting current to said load.

5. The power supply of claim 1 and further including an input filtering and surge limiting circuit.

6. The power supply of claim 5 wherein said input filtering and surge limiting circuit comprises a solenoid coil and a varistor.

7. The power supply of claim 1 and further including an output capacitor and a clamp diode wired in parallel across the load.

8. The power supply of claim 2 wherein said linear regulating supply path comprises a circuit for monitoring the voltage level at an output capacitor and supplying current when needed;

and a switching circuit, responsive to said circuit for montoring the voltage level, for supplying said current.

9. The power supply of claim 8 wherein said circuit for monitoring the voltage level and supplying current comprises a zener diode and wherein said switching circuit comprises a power-supplying transistor and a first switching transistor for switching said power-supplying transistor into a conductive state for conducting current to said load.

10. The power supply of claim 9 and further including an input filtering and surge limiting circuit.

11. The power supply of claim 10 wherein said input filtering and surge limiting circuit comprises a solenoid coil and a varistor.

12. The power supply of claim 11 and further including an output capacitor and a clamp diode wired in parallel across the load.

13. A method for supplying power over a wide range of input line voltages for a circuit protection device and/or fault detection device, said method comprising:

providing power to a load with minimum power loss using a passive supply path comprising a passive supply under nominal input voltage conditions at or near the nominal line voltage;

providing power to said load at low input voltages below a first value using a linear regulating supply path including a linear supply; and

assisting the passive supply using said linear regulating supply path at an input line voltage substantially below the nominal line voltage value and above said first value.

14. The method of claim 13 wherein said providing power under nominal input conditions comprises reducing the supply voltage reactively, eliminating surge current in response to high frequency pulses on the supply input, and rectifying an AC input.

15. The method of claim 13 wherein said providing power at low input voltages and said assisting comprises monitoring the voltage level at an output capacitor and supplying current when needed and in response to said circuit for montoring the voltage level.

16. The method of claim 15 wherein said monitoring the voltage level uses a zener diode and wherein said supplying current comprises switching a power supplying transistor into a conductive state for conducting current to said load.

17. The method of claim 13 and further including input filtering and surge limiting.

18. The method of claim 14 wherein said providing power at low input voltages and said assisting comprises monitoring the voltage level at an output capacitor and supplying current when needed in response to said circuit for montoring the voltage level.

19. The method of claim 18 wherein said monitoring the voltage level uses a zener diode and wherein said supplying current comprises switching a power supplying transistor into a conductive state for conducting current to said load.

20. The method of claim 19 and further including input filtering and surge limiting.

21. A system for supplying power over a wide range of input line voltages for a circuit protection device and/or fault detection device, said system comprising:

passive supply means for providing power to a load with minimum power loss under nominal input voltage conditions at or near the nominal line voltage; and

linear supply means for providing power to said load at low input voltages below a first value and for assisting the passive supply at an input line voltage substantially below the nominal line voltage value and above said first value.

22. The system of claim 21 wherein said passive supply means comprises means for reducing the supply voltage reactively, means for eliminating surge current in response to high frequency pulses on the supply input, and means for rectifying an AC input.

23. The system of claim 21 wherein said linear supply means comprises means for monitoring the voltage level at an output capacitor and means for supplying said current in response to said means for montoring the voltage level.

24. The system of claim 23 wherein said means for monitoring the voltage level includes a zener diode and wherein said means for supplying current comprises means for switching a power supplying transistor into a conductive state for conducting current to said load.

25. The system of claim 21 and further including input means for filtering and surge limiting.

26. The system of claim 22 wherein said linear supply means comprises means for monitoring the voltage level at an output capacitor and means for supplying current in response to said means for montoring the voltage level.

27. The system of claim 26 wherein said means for monitoring the voltage level includes a zener diode and wherein said means for supplying current comprises means for switching a power supplying transistor into a conductive state for conducting current to said load.

28. A linear/passive power converter, comprising:

a passive supply path comprising a passive supply for providing power to a load under nominal input voltage conditions at or near the nominal line voltage with minimum power loss; and

a linear regulating supply path including a linear supply for supplying power to said load during start-up and at input line voltages below a first value, and for assisting the passive supply at input line voltages substantially below the nominal line voltage value and above said first value.