Auxiliary power system

• US 7,802,121 B1
• Filed: 03/27/2006
• Issued: 09/21/2010
• Est. Priority Date: 03/27/2006
• Status: Expired due to Fees

• Current Assignee: NetApp, Inc.
• Original Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Inventors: Zansky, Zoltan, Jacobsen, Bill
• Primary Examiner(s): WANG, ALBERT C
• Application Number:
  US11/390,355
• Time in Patent Office: 1,639 Days
• Field of Search: 307/64, 307/66, 713/340, 320/166, 320/167
• US Class Current: 713/340
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence

Abstract

The present invention is a method and system for providing auxiliary power during a power interruption. An auxiliary power system of the present invention may be added to a power supply to provide auxiliary power during a power dip or power interruption to the power supply. The auxiliary power system may include a power storage device and a power storage charger which is powered by the power supply when power is supplied to the power supply. The power storage charger may charge the power storage device. The auxiliary power system may include a boost converter to provide a constant output voltage during a power interruption. A boost converter may also increase the output voltage supplied by the power storage device suitable for a load receiving power from the power supply.

Claims

1. A system for providing a constant output voltage;

comprising;

a power supply, said power supply receiving an alternating current (AC) input and providing a direct current (DC) output voltage to a load; and

an auxiliary power system incorporated with the power supply, said auxiliary power system including;

a controller coupled to said DC output voltage of said power supply, said controller monitoring an amount of DC output voltage supplied by the power supply;

a capacitor charger coupled to said controller;

a capacitor coupled to said capacitor charger; and

a boost converter including an input coupled to said capacitor and an output coupled to said load, said boost converter further coupled to said controller, said controller including a comparator which compares said DC output voltage supplied by said power supply with a reference voltage, wherein said controller is configured to detect a power interruption when said DC output voltage is less than said reference voltage and said controller is configured to initiate operation of said boost converter whereby said capacitor discharges energy through said boost converter to said load to maintain a substantially constant DC voltage at said load.

2. The system as claimed in claim 1, wherein said capacitor charger receives said DC output voltage from said power supply when said power supply is receiving input power.

3. The system as claimed in claim 1, wherein said boost converter includes an inductor, a transistor and a diode.

4. The system as claimed in claim 1, wherein said controller is a pulse width modulated controller.

5. The system as claimed in claim 4, wherein said pulse width modulated controller controls a duty cycle of said boost converter to provide said substantially constant DC voltage to said load during a power interruption for a period of time greater than 3 seconds.

6. The system as claimed in claim 1, wherein said capacitor is greater than 1 Farad.

7. The system as claimed in claim 6, wherein said capacitor is capable of being charged to 3 volts and discharged to 1 volt.

8. The system as claimed in claim 1, wherein said boost converter is suitable for converting a 3 volt input supply from said capacitor to a 12 volt output supply for said load.