Demand meter having load profile recording capabilities

• US 5,924,051 A
• Filed: 10/20/1997
• Issued: 07/13/1999
• Est. Priority Date: 12/16/1994
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Plis, Mark J., Edge, Ellen D., Maehl, Thomas, Provost, Roland J., Lavoie, Gregory P.
• Primary Examiner(s): WACHSMAN, HAL D
• Application Number:
  US08/954,419
• Time in Patent Office: 631 Days
• Field of Search: 702/60-62, 702/64, 702/65, 702/79, 702/85, 702/176-178, 702/187, 702/189, 364/923.2, 364/528.26, 364/528.3, 364/528.31, 364/528.32, 364/528.33, 324/142, 324/103 R, 324/113-116, 324/134, 324/139, 324/140 R, 324/140 D, 324/141, 705/410, 705/404, 705/411, 340/870.02, 340/870.3, 340/870.16, 340/870, 340/39, 340/687, 235/373-377, 235/116, 235/60.4, 235/60.45, 235/201 R, 235/91 D
• US Class Current: 702/61
• CPC Class Codes: G01R 21/133 by using digital technique

Abstract

A demand electronic electricity meter having load profile recording capabilities is presented. Load profile recording requires memory for storing the recorded information, whereby either on-board memory or external memory is required. Load profile parameters include the number of channels (e.g., 1, 2 or more channels), interval size (e.g., 1, 5, 10, 15, 30 or 60 minutes), quantities to be recorded (e.g., kWh and kvarh, kVAh, or Qh) and channel scalar/divisor (e.g., for each channel, a 2 byte divisor and a 2 byte scalar). With two channels, only two quantities are available for recording, kWh and the one other quantity that the meter has been configured to record, (e.g., kvarh, KVAh, or kQh). For each quantity selected, snapshots of the corresponding total accumulator; (i.e. total kWh and total kvarh, kVAh or kQh) are automatically maintained.

Claims

1. A device for metering electricity comprising:

a measurement scheme for generating measured signals indicative of a quantitative value of electricity being metered;

a signal processor system responsive to said measured signals, said system comprising a digital signal processor and a microcomputer coupled to said digital signal processor, said system further comprising a memory for storing signals including program signals defining an executable algorithm for calculating electricity energy signals; and

a load profile recorder for recording the electricity energy signals in discrete time intervals, inputs for configuring said load profile recorder being transported to said recorder in a standard table format, said inputs comprising at least one of a number of channels, an interval size, quantities to be recorded, and channel scalar and divisor;

said microcomputer programmed to transmit the electricity energy signals to said load profile recorder at predetermined time intervals, said load profile recorder comprising a processor programmed to store electricity energy signals; and

a meter enclosure, said measurement scheme, said signal processor system, and said load profile recorder located at least substantially within said enclosure.

2. The device of claim 1 wherein said measurement scheme comprises:

a voltage sensor for generating voltage signals indicative of the voltage of the electricity being metered;

a current sensor for generating current signals indicative of the current of the electricity being metered; and

wherein said measured signals comprise said voltage and current signals, and said quantitative value comprises voltage and current.

3. The device of claim 2 wherein said signal processor system further comprises:

an A/D converter for converting said voltage and current signals to digital signals indicative thereof.

4. The device of claim 1 wherein said measurement scheme comprises:

a meter disk which rotates in response to the electricity being metered;

a sensor for detecting rotation of said meter disk, said sensor generating a plurality of pulses, said plurality of pulses comprise said measured signals.

5. The device of claim 1 wherein said load profile recorder includes:

an accumulator for accumulating said electricity energy signals during each of said intervals to define a total energy value for each of said intervals, said total energy value for each of said intervals being written to a block within said memory.

6. The device of claim 1 wherein:

said signal processor system includes a real time clock, said discrete time intervals being associated with said real time clock; and

the device further comprising

a battery for maintaining said real time clock during a power fail, said load profile recorder accounting for said discrete time intervals during the power fail.

7. The device of claim 1 further comprising:

a line carrier network interface for two-way communication with a remote management system, said line carrier network interface for receiving time and date update information from the remote management system after recovery from a power fail, said load profile recorder utilizing said time and date update information to account for said discrete time intervals during the power fail.

8. The device of claim 1 wherein said electricity energy signals comprise kilowatt hours (KWhy, kilovar hours (Kvarh), kilovolt amp hours (KVAh), or kiloquadergy hours (KQh).

9. A method for metering electricity using a meter including a digital signal processor for generating digital data representative of energy consumed by a load, a microcomputer coupled to the digital signal processor, and a load profile recorder coupled to the microcomputer, said method comprising the steps of:

transporting to the load profile recorder inputs for configuring the recorder, the inputs being transported in a standard table format, the inputs comprising at least one of a number of channels, a time interval size, quantities to be recorded, and channel scalar and divisor;

generating, in the digital signal processor, digital measurement signals indicative of a quantitative value of electricity being metered;

transmitting the digital signal measurement signals to the microcomputer;

processing, in the microcomputer, the digital measurement signals to generate electricity demand signals;

transmitting, at preselected time intervals, the measurement signals to the load profile recorder;

scaling, in the recorder, the measurement signals; and

recording, in the recorder, at least the scaled electricity demand signals in discrete time intervals.

10. The method of claim 9 wherein said step of generating said measurement signals comprises the steps of:

generating voltage signals indicative of the voltage of the electricity being metered;

generating current signals indicative of the current of the electricity being metered; and

wherein said measurement signals comprise said voltage and current signals, and said quantitative value comprises voltage and current.

11. The method of claim 9 wherein said step of generating said measurement signals comprises:

detecting rotation of a meter disk which rotates in response to the electricity being metered to generate a plurality of pulses, said plurality of pulses comprise said measurement signals.

12. The method of claim 9 wherein said step recording comprises the steps of:

accumulating said electricity energy signals during each of said intervals to define a total energy value for each of said intervals; and

storing said total energy values for each of said intervals in a block of memory.

13. The method of claim 12 further comprising the step of multiplying said electricity energy signals by a scalar and dividing by a divisor prior to accumulating.

14. The method of claim 9 further comprising the step of:

maintaining a real time clock during a power fail to account for said discrete time intervals during the power fail.

15. The meter of claim 9 further comprising the step of:

receiving time and date update information after recovery from a power fail to account for said discrete time intervals during the power fail.

16. An electricity meter for measuring electricity and generating electricity energy signals in response thereto, the meter including a microcomputer and a meter enclosure, wherein the improvement comprises:

a load profile recorder located within the meter enclosure and comprising a processor, said processor electrically coupled to the microcomputer for recording electricity energy signals in discrete time intervals, said load profile recorder comprising a processor programmed to scale the energy signals and to store at least the scaled signals, inputs for configuring said load profile recorder being transported to said recorder in a standard table format, said inputs comprising at least one of a number of channels, an interval size, quantities to be recorded, and channel scalar and divisor.

17. The meter of claim 16 wherein said load profile recorder includes:

an accumulator for accumulating said electricity energy signals during each of said intervals to define a total energy value for each of said intervals, said total energy value for each of said intervals being written to a block of memory in said meter.

18. The meter of claim 16 wherein said meter further comprises:

a real time clock, said discrete time intervals being associated with said real time clock; and

a battery for maintaining said real time clock during a power fail, said load profile recorder accounting for said discrete time intervals during the power fail.

19. The meter of claim 16 further comprising:

a line carrier network interface for two-way communication with a remote management system, said line carrier network interface for receiving time and date update information from the remote management system after recovery from a power fail, said load profile recorder utilizing said time and date update information to account for said discrete time intervals during the power fail.

20. A demand only electronic register for measuring electricity and generating electricity demand signals in response thereto, wherein the improvement comprises:

a load profile recorder for recording electricity demand signals in discrete time intervals, said load profile recorder comprising a processor and a memory, said processor programmed to store demand signals in said memory, inputs for configuring said load profile recorder being transported to said recorder in a standard table format, said inputs comprising at least one of a number of channels, an interval size, quantities to be recorded, and channel scalar and divisor.

21. The register of claim 20 wherein said load profile recorder includes:

an accumulator for accumulating said electricity demand signals during each of said intervals to define a total energy value for each of said intervals, said total demand value for each of said intervals being written to a block of memory in said register.

22. The register of claim 20 wherein said register further comprises:

a real time clock, said discrete time intervals being associated with said real time clock; and

a battery for maintaining said real time clock during a power fail, said load profile recorder accounting for said discrete time intervals during the power fail.

23. The register of claim 20 further comprising:

a line carrier network interface for two-way communication with a remote management system, said line carrier network interface for receiving time and date update information from the remote management system after recovery from a power fail, said load profile recorder utilizing said time and date update information to account for said discrete time intervals during the power fail.

24. A device for metering electricity comprising:

a measurement scheme comprising a digital signal processor for generating measured signals indicative of a quantitative value of electricity being metered; and

a signal processor system responsive to said measured signals, and having a memory for storing signals including program signals defining an executable algorithm for calculating electricity energy signals, said system comprising recorder for executing an executable algorithm for recording electricity energy signals in discrete time intervals, said recorder comprising a processor programmed to record energy signals, inputs for configuring said recorder being transported to said recorder in a standard table format, said inputs comprising at least one of a number of channels, an interval size, quantities to be recorded, and channel scalar and divisor; and

a meter enclosure, said measurement scheme and said signal processor system located at least substantially within said enclosure.

25. The device of claim 24 wherein said signal processor system includes:

an accumulator for accumulating said electricity energy signals during each of said intervals to define a total energy value for each of said intervals, said total energy value for each of said intervals being written to a block within said memory.

26. The device of claim 24 wherein:

said signal processor system includes a real time clock, said discrete time intervals being associated with said real time clock; and

the device further comprising

a battery for maintaining said real time clock during a power fail, said signal processor system accounting for said discrete time intervals during the power fail when recording.

27. The device of claim 24 further comprising:

a line carrier network interface for two-way communication with a remote management system, said line carrier network interface for receiving time and date update information from the remote management system after recovery from a power fail, said signal processor system utilizing said time and date update information to account for said discrete time intervals during the power fail when recording.

28. The device of claim 24 wherein said electricity energy signals comprise kilowatt hours (KWh), kilovar hours (Kvarhj, kilovolt amp hours (KVAh), or kiloquadergy hours (Kqh).