Energy-Efficient Standby Mode In A Switching Power Supply

• US 20120026763A1
• Filed: 04/27/2009
• Published: 02/02/2012
• Est. Priority Date: 04/27/2009
• Status: Active Grant

• Current Assignee: Valtrus Innovations Limited (f/k/a Dolya Holdco 9 Limited) (Key Patent Innovations Limited)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: Humphrey, Daniel, Bemat, Mohamed Amin, Mohr, David Paul
• Granted Patent: US 9,401,635 B2
• Time in Patent Office: Days
• US Class Current: 363/65
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

A switching power supply includes power factor correction circuitry and a standby output converter. One or more loads may be coupled to one or more outputs of the switching power supply. The switching power supply is configured to disable the power factor correction circuitry under some load conditions and to enable the power factor correction circuitry under other load conditions. As a consequence, power that would have been drawn by the power factor correction circuitry is conserved when the power factor correction circuitry is disabled.

Claims

1. A switching power supply, comprising:

rectification circuitry;

an energy storage element;

first and second output converters, each having an input connected to the energy storage element;

power factor correction circuitry connected between the rectification circuitry and the energy storage element;

bypass circuitry connected in parallel with the power factor correction circuitry; and

control circuitry configured to disable the power factor correction circuitry when the first output converter is active and the second output converter is not active, and to enable the power factor correction circuitry when the second output converter is active.

2. The switching power supply of claim 1, wherein:

the control circuitry comprises a sense input configured to sense a voltage indicating whether it is possible to operate the first output converter while the power factor correction circuitry is disabled; and

wherein the control circuitry is configured not to disable the power factor correction circuitry when the voltage indicates that such operation is not possible.

3. The switching power supply of claim 2, wherein:

the voltage indicates whether a DC level at the input of the first output converter, created by the rectification circuitry and communicated thereto via at least the bypass circuitry, is within a range of input levels tolerated by the input of the first output converter.

4. The switching power supply of claim 3, wherein the voltage is an analog level taken from at least one node chosen from the following group:

an AC input to the rectification circuitry;

an output of the rectification circuitry; and

the input of the first output converter.

5. The switching power supply of claim 2, wherein the voltage is a binary level taken from at least one node chosen from the following group:

a control switch circuit;

a control jumper circuit; and

a memory element.

6. The switching power supply of claim 1, wherein:

the power factor correction circuitry comprises a boost converter and the bypass circuitry is a diode.

7. The switching power supply of claim 1, wherein:

the power factor correction circuitry is not a boost converter and the bypass circuitry comprises a switch operated by the control circuitry.

8. A method of operating a switching power supply, comprising:

determining whether a load of the power supply is in a standby mode; and

disabling power factor correction circuitry in the power supply if it is determined that the load is in the standby mode;

else enabling the power factor correction circuitry.

9. The method of claim 8, further comprising:

determining whether it is possible for the power supply to drive the load with the power factor correction circuitry disabled while the load is in the standby mode; and

not disabling the power factor correction circuitry if it is determined that it is not possible for the power supply to drive the load with the power factor correction circuitry disabled while the load is in the standby mode.

10. The method of claim 8, wherein:

the determining step comprises determining whether the load is in the standby mode or whether it is in an alternate mode requiring more power than the standby mode.

11. The method of claim 8, wherein:

the load comprises first and second loads;

the standby mode corresponds to a state in which the first load is active and the second load is not active; and

the determining step comprises determining whether the second load is or is about to become active.

12. A system, comprising:

a switching power supply having power factor correction circuitry and a standby output converter; and

a load coupled to an output of the switching power supply;

wherein the switching power supply is configured to disable the power factor correction circuitry when the load is in a standby mode powered by the standby output converter, and to enable the power factor correction circuitry when the load is in an alternate mode requiring more power than the standby mode.

13. The system of claim 12, wherein:

the load comprises a computing device.

14. The system of claim 12, further comprising:

mode determination logic in the power supply configured to determine, responsive either to a control signal from the load or to a sensed level of power demanded by the load, whether the load is in the standby or the alternate mode.

15. The system of claim 12, wherein:

the load comprises first and second loads;

the standby mode corresponds to a state in which the first load is active and the second load is not active; and

the alternate mode corresponds to a state in which the second load is active.