LOAD-SIDE VOLTAGE DETECTION VIA ELECTRIC METERING PROCESSING

• US 20120078546A1
• Filed: 09/28/2010
• Published: 03/29/2012
• Est. Priority Date: 09/28/2010
• Status: Abandoned Application

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.), General Electric Company
• Original Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.), General Electric Company
• Inventors: Lee, Robert Edward Jr., Mancuso, Marjorie Jo, Junker, John Paul, Lavoie, Gregory Paul
• Application Number:
  US12/892,005
• Publication Number:
  US 20120078546A1
• Time in Patent Office: Days
• US Class Current: 702/61
• CPC Class Codes: G01R 19/155 Indicating the presence of voltage
• CPC Class Codes: G01R 22/06 by electronic methods

Abstract

Load-side voltage detection via electric metering processing is disclosed. In one aspect, load-side voltage is provided as an input to a metering processing unit. The metering processing unit determines a voltage level of the load-side voltage. An application processing unit uses the voltage level to control operation of a service disconnect relay.

Claims

1. A utility metering device, comprising:

a load-side voltage detection circuit that detects load-side voltage;

a metering processing unit that receives the load-side voltage from the load-side voltage detection circuit and measures the voltage level of the detected load-side voltage; and

an application processing unit that receives the measured voltage level from the metering processing unit and determines the presence of the load-side voltage from the measured voltage level.

2. The utility metering device according to claim 1, further comprising a service disconnect relay controlled by operational commands provided from the application processing unit.

3. The utility metering device according to claim 2, wherein the application processing unit directs the service disconnect relay to remain in an open state in response to determining the presence of load-side voltage and directs the service disconnect relay to a closed state in response to determining the absence of load-side voltage.

4. The utility metering device according to claim 1, further comprising a phase voltage measurement device that detects line-side voltage.

5. The utility metering device according to claim 4, wherein the metering processing unit is further configured to receive the line-side voltage from the phase voltage measurement device for facilitating a determination of a phase relationship between the line-side voltage and the load-side voltage provided by the load-side detection circuit.

6. The utility metering device according to claim 5, wherein the metering processing unit calculates a voltage quantity defined as:

V_line-load²h=Σ

_k=1^N(V_line−

V_load)², where V_line and V_load are line and load-side voltage samples, respectively, N is the number of samples in a momentary interval, h is hours and k is the index for the summation.

7. The utility metering device according to claim 6, wherein the application processing unit determines the phase relationship between the line-side voltage and the load-side voltage provided by the load-side detection circuit as a function of the calculated voltage quantity.

8. The utility metering device according to claim 7, wherein the line-side voltage and the load-side voltage are out of phase in response to determining that there is a load-side voltage present and that V²_line-loadh is above a first predefined threshold, and wherein the line-side voltage and the load-side voltage are in phase in response to determining that a load-side voltage is present and that V²_line-loadh is below a second predefined threshold.

9. The utility metering device according to claim 7, wherein the application processing unit uses the determined phase relationship to determine if a utility service has been altered.

10. The utility metering device according to claim 9, further comprising an output that generates an alert in response to determining that the utility service has been altered.

11. An energy meter, comprising:

a service disconnect relay;

a load-side voltage detection circuit configured to detect load-side voltage;

a metering processing unit configured to receive the load-side voltage as an input from the load-side voltage detection circuit and measure magnitude of the detected load-side voltage; and

an application processing unit configured to receive the measured magnitude of the detected load-side voltage from the metering processing unit and control operation of the service disconnect relay as a function of the measured magnitude.

12. The energy meter according to claim 11, wherein the application processing unit is configured to maintain the service disconnect relay in an open state in response to determining that the measured magnitude is indicative of a presence of load-side voltage and close the service disconnect relay in response to determining the absence of load-side voltage.

13. The energy meter according to claim 11, further comprising a phase voltage measurement device that is configured to detect line-side voltage.

14. The energy meter according to claim 13, wherein the metering processing unit is further configured to receive the line-side voltage from the phase voltage measurement device for facilitating a determination of a phase relationship between the line-side voltage and the load-side voltage provided by the load-side detection circuit.

15. The energy meter according to claim 14, wherein the metering processing unit calculates a voltage quantity defined as:

V_line-load²h=Σ

_k=1^N(V_line−

V_load)², where V_line and V_load are line and load-side voltage samples, respectively, N is the number of samples in a momentary interval, h is hours and k is the index for the summation.

16. The energy meter according to claim 15, wherein the application processing unit determines the phase relationship between the line-side voltage and the load-side voltage provided by the load-side detection circuit as a function of the calculated voltage quantity, wherein the application processing unit uses the determined phase relationship to determine if a utility service has been altered.

17. The energy meter according to claim 16, wherein the line-side voltage and the load-side voltage are out of phase in response to determining that there is a load-side voltage present and that V²_line-loadh is above a first predefined threshold, and wherein the line-side voltage and the load-side voltage are in phase in response to determining that a load-side voltage is present and that V²_line-loadh is below a second predefined threshold.

18. A method for restoring an electric service, comprising:

detecting a load-side voltage;

inputting the load-side voltage to a metering processing unit;

measuring magnitude of the load-side voltage;

determining the presence of the load-side voltage as a function of the measured magnitude; and

restoring the electric service in response to determining that the measured magnitude is indicative of the absence of load-side voltage.

19. The method according to claim 18, further comprising prohibiting restoration of the electric service in response to determining that the measured magnitude is indicative of a presence of load-side voltage.

20. The method according to claim 18, further comprising:

detecting line-side voltage;

determining a phase relationship between line-side voltage and the load-side voltage;

determining if the electric service has been altered as a function of the phase relationship between the line-side voltage and the load-side voltage; and

generating an alert in response to determining that the electric service has been altered.