System and method for providing power to a power meter connected to a power line

• US 9,018,939 B2
• Filed: 11/22/2011
• Issued: 04/28/2015
• Est. Priority Date: 11/23/2010
• Status: Active Grant

• Current Assignee: Corinex Communications Corporation
• Original Assignee: Corinex Communications Corporation
• Inventors: Sobotka, Peter, Shi, Xiao Ming, Long, Yan
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): PRETLOW, DEMETRIUS R
• Application Number:
  US13/302,818
• Publication Number:
  US 20120126790A1
• Time in Patent Office: 1,253 Days
• Field of Search: 324/142, 324/76.11, 340/870.02
• US Class Current: 324/142
• CPC Class Codes: G01D 4/002 Remote reading of utility meters
• CPC Class Codes: G01D 4/004 Remote reading of utility meters to a fixed location
• CPC Class Codes: G01R 19/0007 Frequency selective voltage or current level measuring measuring frequency G01R23/00; testing attenuation in line transmission systems H04B3/48; monitoring testing in transmission systems H04B17/00
• CPC Class Codes: G01R 19/165 Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
• CPC Class Codes: G01R 31/42 AC power supplies
• CPC Class Codes: G08C 19/28 using pulse code
• CPC Class Codes: H04B 2203/5433 Remote metering
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04B 3/546 Combination of signalling, telemetering, protection circuits for remote indication of supply or distribution network condition H02J13/00
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading
• CPC Class Codes: Y04S 40/18 Network protocols supporting networked applications, e.g. including control of end-device applications over a network

Abstract

The disclosure relates to a meter for monitoring usage of power provided by a power transmission system to a site. The meter comprises: a meter module connected to a power feed associated with the power transmission system to provide readings relating to the power; a messaging module to provide messages to the power transmission system; a connection to an alternating current (AC) power supply; a rectifier circuit connected to the AC power supply to generate a direct current (DC) power signal; a capacitive circuit connected to an output of the rectifier circuit, the capacitive circuit including a capacitor for storing a voltage for temporarily providing replacement power for the rectifier circuit; and a switching regulator circuit connected to the output of the rectifier circuit and the capacitive circuit, the switching regulator converting the DC voltage signal to a stepped down voltage signal for the meter module.

Claims

1. A meter for monitoring usage of power provided by a power transmission system to a site, the meter comprising:

a meter module connected to a power feed associated with the power transmission system to provide readings relating to the power;

a connection to a household alternating current (AC) power supply providing power to the meter;

a rectifier circuit connected to the household AC power supply to generate a direct current (DC) power signal;

a capacitive circuit connected to an output of the rectifier circuit, the capacitive circuit including a capacitor for storing a voltage for temporarily providing replacement power for the rectifier circuit;

a switching regulator circuit connected to the output of the rectifier circuit and the capacitive circuit, the switching regulator converting the DC voltage signal to a stepped down voltage signal for the meter module;

a voltage detection circuit connected to the capacitive circuit to detect a low voltage condition where an output from the capacitive circuit drops below an operational threshold for the meter and to generate a low voltage signal upon detection of the drop; and

a message generation module for receiving the low voltage signal and for generation a power loss message for transmission from the meter and carried on a message carrier having a carrier frequency between approximately 2 MHz and 30 MHz to bridge a discontinuity in the power transmission system.

2. The meter for monitoring usage of power as claimed in claim 1, wherein:

when the household AC power supply fails, the capacitive circuit provides a voltage to the switching regulator through the capacitor and a resistor network to provide power for the switching regulator.

3. The meter for monitoring usage of power as claimed in claim 1, wherein:

the meter module maintains an internal clock for synchronization with a clock maintained by a head end.

4. The meter for monitoring usage of power as claimed in claim 3, wherein:

the meter module adjusts the internal clock with the clock maintained by the head end when a discrepancy between the internal clock and the clock maintained by the head end is detected.

5. The meter for monitoring usage of power as claimed in claim 1, wherein upon detection of the low voltage condition, the meter module:

tracks an unsynchronized time for the meter, the unsynchronized time beginning at a time associated with detection of the low voltage condition.

6. The meter for monitoring usage of power as claimed in claim 5, wherein upon a re-boot of the meter, the meter module:

compares the unsynchronized time with a clock maintained by a head end.

7. The meter for monitoring usage of power provided by a power transmission system to a site as claimed in claim 1, further comprising:

a disconnect manager module that controls the connection to the household AC power supply to connect and disconnect the meter from the household AC power supply based on a control action signal received by the disconnect manager module.

8. The meter for monitoring usage of power provided by a power transmission system to a site as claimed in claim 7, wherein:

the disconnect manager module controls the connection to disconnect the meter from the household AC power supply when either an over-voltage or an over-current situation is detected on the household AC power supply.

9. The meter for monitoring usage of power provided by a power transmission system to a site as claimed in claim 1, wherein:

the disconnect manager module also controls the connection to disconnect the meter from the household AC power supply when a total power reading for the meter for a period of time exceeds a threshold.

10. The meter for monitoring usage of power provided by a power transmission system to a site as claimed in claim 1, further comprising:

a schedule manager module that schedules for the meter, meter readings, power rate switching and synchronization of an internal clock with a clock maintained by a head end.

11. A method for monitoring usage of power provided by a power transmission system to a site at a meter, the method comprising:

charging a capacitive circuit located between a rectifier circuit connected to a household alternating current (AC) power supply for the meter that generates a direct current (DC) power signal for the meter and a switching regulator circuit connected to the output of the rectifier circuit, the switching regulator converting the DC voltage signal to a stepped down voltage signal for the meter module;

when the household AC power supply fails, discharging the capacitive circuit to provide a voltage to the switching regulator;

detecting a low voltage condition where an output from the capacitive circuit drops below an operational threshold for the meter; and

generating and sending a power loss message upon detection of the low voltage condition to the power transmission system from the meter carried on a message carrier having a carrier frequency between approximately 2 MHz and 30 MHz to bridge a discontinuity in the power transmission system.

12. The method for monitoring usage of power provided by a power transmission system to a site at a meter as claimed in claim 11, further comprising:

maintaining an internal clock in the meter for synchronization with a clock maintained by a head end; and

adjusting the internal clock with the clock maintained by the head end when a discrepancy between the internal clock and the clock maintained by the head end is detected.

13. The method for monitoring usage of power provided by a power transmission system to a site at a meter as claimed in claim 11, further comprising:

controlling the connection to the household AC power supply to connect and disconnect the meter from the household AC power supply based on a control action signal.

14. The method for monitoring usage of power provided by a power transmission system to a site at a meter as claimed in claim 13, wherein:

the meter is disconnected from the household AC power supply when either an over-voltage or an over-current situation is detected on the household AC power supply.

15. The method for monitoring usage of power provided by a power transmission system to a site at a meter as claimed in claim 14, further comprising:

disconnecting the meter from the household AC power supply when a total power reading for the meter for a period of time exceeds a threshold.

16. The method for monitoring usage of power provided by a power transmission system to a site at a meter as claimed in claim 11, further comprising:

scheduling for the meter, meter readings, power rate switching and synchronization of an internal clock with a clock maintained by a head end.