METHOD AND ARRANGEMENT FOR CONTROLLING DC POWER OUTPUT IN UTILITY METER

• US 20130054165A1
• Filed: 08/29/2011
• Published: 02/28/2013
• Est. Priority Date: 08/29/2011
• Status: Active Grant

• Current Assignee: Landis+Gyr AG (Landis+Gyr Group AG)
• Original Assignee: Landis+Gyr Inc. (Landis+Gyr Group AG)
• Inventors: Ramirez, Anibal Diego
• Granted Patent: US 10,036,768 B2
• Time in Patent Office: Days
• US Class Current: 702/62
• CPC Class Codes: G01R 19/16547 voltage or current in AC supplies switching for protection H02H; circuits for emergency power supply H02J9/00
• CPC Class Codes: G01R 21/06 by measuring current and voltage G01R21/08 - G01R21/133 take precedence
• CPC Class Codes: G01R 22/061 Details of electronic electricity meters
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: H02H 3/207 also responsive to under-voltage window comparators for indication G01R19/165
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence

Abstract

An electricity meter comprises a voltage sensor configured to determine an AC line voltage. A measurement circuit is coupled to the voltage sensor and is configured to determine energy consumption data based at least in part on the AC line voltage. A communications device is coupled to the measurement circuit and is configured to transmit the energy consumption data to a remote location. The electricity meter further includes a power supply configured to provide a DC voltage to the communications device. A switch is positioned between the power supply and the communications device. A switch controller is coupled to the measurement circuit and is configured to control the switch and the associated DC voltage supplied to the communications device depending at least in part on the AC line voltage.

Claims

1. An electricity meter comprising:

a voltage sensor configured to determine an AC line voltage;

a measurement circuit coupled to the voltage sensor and configured to determine energy consumption data based at least in part on the AC line voltage;

a communications device coupled to the measurement circuit and configured to transmit the energy consumption data to a remote location;

a power supply configured to provide a DC voltage to the communications device;

a switch positioned between the power supply and the communications device; and

a switch controller coupled to the measurement circuit, the switch controller configured to control the switch and the associated DC voltage supplied to the communications device depending at least in part on the AC line voltage.

2. The electricity meter of claim 1 wherein the switch controller and the measurement circuit are provided by a processor.

3. The electricity meter of claim 1 wherein the switch controller is configured to adjust the duty cycle of the switch depending at least in part on the AC line voltage.

4. The electricity meter of claim 3 wherein the switch is a transistor.

5. The electricity meter of claim 1 further comprising a temperature sensor coupled to the switch controller, wherein the switch controller is further configured to control the switch depending at least in part on an output of the temperature sensor provided to the switch controller.

6. The electricity meter of claim 1 further comprising a current sensor configured to determine a current flowing through the switch, wherein the switch controller is further configured to control the switch depending at least in part on an output of the current sensor provided to the switch controller.

7. The electricity meter of claim 6 wherein the DC voltage is provided to the switch controller, and wherein the switch controller is further configured to control the switch depending at least in part on the DC voltage from the power supply.

8. The electricity meter of claim 1 further comprising a holdup capacitor coupled to the switch.

9. The electricity meter of claim 1 wherein the switch controller is configured to control the switch such that a first amount of power is provided to the communications device if the AC line voltage is below a threshold voltage, and a second amount of power is provided to the communications device if the AC line voltage is not below the threshold voltage.

10. The electricity meter of claim 9 wherein the threshold voltage is about 96 Vrms.

11. The electricity meter of claim 9 wherein the first amount of power is about 3 W and the second amount of power is about 6 W.

12. An electricity meter comprising:

a communications device configured to transmit energy consumption data;

a power supply configured to provide DC power to the communications device; and

a switch positioned between the power supply and the communications device, the switch operable in a first mode and a second mode such that the DC power is provided to the communications device when the switch is in the first mode and the DC power is blocked from the communications device when the switch is in the second mode.

13. The electricity meter of claim 12 further comprising a switch controller configured to control the switch between the first mode and the second mode based at least in part on the AC line voltage.

14. The electricity meter of claim 13 further comprising a measurement circuit configured to determine the energy consumption data based in part on the AC line voltage.

15. The electricity meter of claim 14 wherein the switch is a MOSFET transistor and the switch controller and measurement circuit are provided on a single chip.

16. The electricity meter of claim 12 further comprising a switch controller configured to control the switch between the first mode and the second mode based at least in part on a temperature.

17. The electricity meter of claim 12 further comprising a current sensor and a switch controller, the current sensor configured to determine the current flowing through the switch, and the switch controller configured to control the switch between the first mode and the second mode based at least in part on the current flowing through the switch.

18. A method of providing power to a communications device in an electricity meter, the method comprising:

monitoring an electricity meter parameter; and

controlling a switch such that a first amount of power is provided to the communications device when the electricity meter parameter is less than a threshold amount and a second amount of power is provided to the communications device when the electricity meter parameter is not less than the threshold amount.

19. The method of claim 18 wherein the electricity meter parameter is an AC line voltage.

20. The method of claim 18 wherein the electricity meter parameter is a temperature within the electricity meter.