Device for measuring two phase power with single voltage input

• US 9,128,131 B2
• Filed: 04/07/2011
• Issued: 09/08/2015
• Est. Priority Date: 04/07/2011
• Status: Active Grant

• Current Assignee: Haier US Appliance Solutions, Inc. DBA GE Appliances (Haier Group Company)
• Original Assignee: General Electric Company
• Inventors: Finch, Michael Francis, Huff, Joshua Blake
• Primary Examiner(s): Nghiem, Michael
• Assistant Examiner(s): RABOVIANSKI, IVAN I
• Application Number:
  US13/081,844
• Publication Number:
  US 20120259566A1
• Time in Patent Office: 1,615 Days
• Field of Search: 702/60, 702/61, 702/62
• US Class Current: 1/1
• CPC Class Codes: G01R 21/06 by measuring current and voltage G01R21/08 - G01R21/133 take precedence
• CPC Class Codes: G01R 21/1331 Measuring real or reactive component, measuring apparent energy

Abstract

A device and method for more accurately measuring power consumption in a residential application without having to make connections to high voltage sources in a distribution panel. Since the device calculating the power consumption generally needs to be powered to perform its functions (e.g., plugged into wall outlet), the disclosure utilizes the power supply as a voltage source for measuring voltage without having to make connections to the panel.

Claims

1. A device for measuring a power consumption of a building receiving power from a conventional 120/240 volt AC power source comprising a first power line, a second power line and a neutral line, and at least one single-phase power outlet configured to receive a voltage and coupled to the first power line of the 120/240 volt AC power source, the device configured for operable connection to the at least one single-phase power outlet, the device comprising:

a metering microcontroller unit comprising;

a voltage input terminal configured to operably receive the voltage of the first power line from one of the at least one single-phase power outlet, wherein the metering microcontroller unit is configured to measure a first voltage value from the received voltage; and

a first current input terminal and a second current input terminal configured to respectively receive a first current signal and a second current signal, the first current signal and the second current signal being indicative of an amount of current flowing in the first power line and the second power line respectively, wherein the metering microcontroller unit is further configured to calculate a second voltage value based on the measured first voltage value, the second voltage value being indicative of the voltage of the second power line, and to calculate the power consumption of the building based on the measured first voltage value, the calculated second voltage value, and the first and the second current signals.

2. The device as set forth in claim 1, wherein first and the second current signals are provided to the metering microcontroller unit via a first and a second current transformers connected to a respective power line of the first and the second power lines.

3. The device as set forth in claim 1, further comprising a communication interface for communicating data relating to the power consumption.

4. The device as set forth in claim 3, wherein the communication interface comprises a wireless communication interface for communicating power consumption information to a remote device.

5. The device as set forth in claim 1, further comprising a display for displaying power consumption information to a user.

6. The device as set forth in claim 1, further comprising a first current transformer connectable to the first power line and a second current transformer connectable to the second power line, the first and second current transformers connected to a respective current input terminal of the first and the second current input terminals of the metering microcontroller unit.

7. The device as set forth in claim 1, further comprising a power supply, wherein the power supply and the metering microcontroller unit are housed within a housing of a two prong plug comprising two electrically conductive prongs configured to plug into one of the at least one single-phase power outlet, the power supply connectable to the single-phase power outlet via the electrically conducting prongs.

8. A system for measuring a power consumption of a-building, the system comprising:

a main power distribution panel for receiving a first power line and a second power line and distributing power to at least one household load;

at least one single phase power outlet configured to receive a voltage and coupled to the first power line through the main power distribution panel;

a device for measuring the power consumption of the building, wherein the device comprises a metering microcontroller unit comprising;

a voltage input terminal arranged to operably receive the voltage of the first power line from one of the at least one single-phase power outlet, wherein the metering microcontroller unit is configured to measure a first voltage value from the received voltage; and

a first current input terminal and a second current input terminal configured to respectively receive a first current signal and a second current signal, the first current signal and the second current signal being indicative of an amount of current flowing in the first power line and the second power line respectively,

wherein the metering microcontroller unit is further configured to calculate a second voltage value based on the measured first voltage value, the second voltage value being indicative of the voltage of the second power line, and to calculate the power consumption of the building based on the measured first voltage value, the calculated second voltage value, and the first and the second current signals; and

a first current transformer and a second current transformer each associated with a respective power line of the first and the second power lines for providing the first and the second current signals to the respective current input terminal of the first and the second current input terminals of the device for measuring the power consumption.

9. A device for measuring a power consumption of a-building, the device comprising:

a power supply including a first power supply line and a second power supply line, the first power supply line connectable to at least one single-phase power outlet configured to receive a voltage therefrom; and

a microprocessor connected to the power supply and configured to;

receive a first current signal indicative of an amount of current flowing in the first power line supplying power to the building,

receive a second current signal indicative of the amount of current in the second power line supplying power to the building,

measure a first voltage value from the received voltage;

calculate a second voltage value as the negative of the measured first voltage value, the second voltage value being indicative of the voltage of the second power supply line; and

derive the power consumption of the building by integrating with respect to time the sum of the measured first voltage value multiplied by the amount of current flowing in the first power line and the calculated second voltage value multiplied by the amount of current flowing in the second power line.

10. The device as set forth in claim 9, further comprising a user interface.

11. The device as set forth in claim 9, wherein the power supply and the microprocessor are housed within a housing of two prong plug comprising two electrically conductive prongs configured to plug into one of the at least one single-phase power outlet, the power supply connectable to the single-phase power outlet via the electrically conducting prongs.

12. A method of measuring a power consumption of a two-phase power distribution system having a distribution panel, the method comprising:

measuring a first current value indicative of the amount of current flowing in a first power line supplying power to the distribution panel;

measuring a second current value indicative of the amount of current flowing in a second power line supplying power to the distribution panel;

measuring a voltage first value of either the first or the second power line via a single-phase power outlet configured to receive a single voltage and coupled to the first or the second power lines via the distribution panel;

calculating a second voltage value based on the measured first voltage value, the second voltage value being indicative of the voltage of the first or the second power lines not coupled to the single-phase power outlet; and

calculating the power consumption of the building based on the first current value, the second current value, the measured first voltage value, and the calculated second voltage value.

13. The method as set forth in claim 12, wherein calculating the power consumption of the building comprises taking an integral with respect to time of the sum of the products of the measured first voltage value and the first current value and the product of the calculated second voltage value and the second current value.

14. The method as set forth in claim 13, further comprising communicating information related to the power consumption to a remote device via a communication interface.