System for Accurately Detecting Electricity Theft

• US 20100007336A1
• Filed: 01/12/2009
• Published: 01/14/2010
• Est. Priority Date: 07/13/2007
• Status: Active Grant

• Current Assignee: GRID20/20, Inc. (International Broadband Electric Communications Incorporated)
• Original Assignee: GRID20/20, Inc. (International Broadband Electric Communications Incorporated)
• Inventors: de Buda, Eric George
• Granted Patent: US 8,461,823 B2
• Time in Patent Office: Days
• US Class Current: 324/127
• CPC Class Codes: G01R 15/181 using coils without a magnetic core, e.g. Rogowski coils
• CPC Class Codes: G01R 22/06 by electronic methods
• 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 3/56 Circuits for coupling, blocking, or by-passing of signals

Abstract

There is disclosed a method of monitoring an electrical network of the type having a feeder line connected to a plurality of distribution transformers, each distribution transformer being in turn coupled to a load which may be provided with a customer meter. The method includes the steps of recording an accumulated in-phase current at each of the distribution transformers over a time period and recording for the same time period an accumulated in-phase current at the feeder line. The sum of the accumulated in-phase currents recorded at the distribution transformers are then compared to the accumulated in-phase current recorded at the feeder line. The method may also include the steps of recording accumulated in-phase currents at the customer meters and comparing their sum with the accumulated in-phase current measured at the distribution transformers coupled to the customer meters. The method may further include a method of automatically detecting the configuration of the network to determine on which phase the customer meters are connected to, and to which distribution transformer said customer meters are connected to, and further, where on the network, relative to a plurality of feeder meters, each of the distribution transformers are connected.

Claims

1. A method of monitoring an electrical network, the network having a feeder line connected to a plurality of distribution transformers, at least one distribution transformer being in turn coupled to a load, the method comprising the steps of:

recording an accumulated in-phase current at each of the distribution transformers over a time period;

recording for the same time period an accumulated in-phase current at the feeder line;

comparing a sum of the accumulated in-phase currents recorded for the distribution transformers to the accumulated in-phase current recorded at the feeder line.

2. The method of claim 1 further comprising the step of applying a transformation ratio when comparing the sum of the accumulated in-phase currents recorded for the distribution transformers with the feeder line accumulated in-phase current.

3. A method of monitoring an electrical network, the network having a feeder line connected to a plurality of distribution transformers, at least two of said distribution transformers each being connected to at least one customer meter, the method comprising the steps of:

a recording an accumulated in-phase current at the feeder line for a time period;

b recording an accumulated in-phase current at each of the customer meters for the same time period, and

c comparing the accumulated in-phase current recorded at the feeder line to a sum of the accumulated in-phase currents recorded at the customer meters.

4. The method of claim 3 further comprising the step of applying a transformation ratio when comparing the sum of the accumulated in-phase currents recorded for the customer meters with the feeder line accumulated in-phase current.

5. A method of monitoring an electrical network, the network having a distribution transformer connected to at least one customer meter, the method comprising the steps of:

a recording an accumulated in-phase current at the distribution transformer;

b recording an accumulated in-phase current at each of the customer meters, and

c comparing the accumulated in-phase current recorded at the distribution transformer with the sum of the accumulated in-phase currents recorded at the customer meters.

6. The method of claim 5 further comprising the step of applying a transformation ratio when comparing the accumulated in-phase current recorded at the distribution transformer with the sum of the accumulated in-phase currents recorded at the customer meters.

7. A method of metering electricity having current and voltage comprising the steps of:

a continuously determining a magnitude of a component of the current that is in phase with the voltage;

b integrating this component over time, and

c providing a numerical output corresponding to the result of the integration.

8. The method of claim 7 in which the magnitude of the component of the current that is in phase with the voltage is determined by multiplying a current signal with a sinusoidal waveform of fixed amplitude that is in phase with the voltage.

9. The method of claim 7 in which the magnitude of the component of the current that is in phase with the voltage is determined by multiplying a current signal with a sinusoidal waveform of varying amplitude, that is in phase with the voltage and continuously dividing by the amplitude of the sinusoidal waveform.

10. The method of claim 9 in which the sinusoidal waveform of varying amplitude is a voltage waveform.

11. The method of claim 7 in which the magnitude of the component of the current that is in phase with the voltage is determined by multiplying the magnitude of the current with a power factor.

12. The method of claim 11 in which the power factor is determined by measuring a phase angle between the voltage and the current and determining its cosine.

13. The method of claim 11 in which the power factor is determined by dividing an active energy by an apparent energy.