Electric power system control with measurement of energy demand and energy efficiency using t-distributions

• US 10,666,048 B2
• Filed: 01/11/2018
• Issued: 05/26/2020
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Dominion Energy, Inc.
• Original Assignee: Dominion Energy, Inc.
• Inventors: Hall, Edmund J., Tyler, Stephen J.
• Primary Examiner(s): Karim, Ziaul
• Application Number:
  US15/868,415
• Publication Number:
  US 20180138704A1
• Time in Patent Office: 866 Days
• Field of Search: 700295-298
• CPC Class Codes: G01R 21/00 Arrangements for measuring electric power or power factor G01R7/12 takes precedence
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 13/00017 using optical fiber
• CPC Class Codes: H02J 13/00022 using wireless data transmission
• CPC Class Codes: H02J 13/00024 by means of mobile telephony
• CPC Class Codes: H02J 13/00026 involving a local wireless network, e.g. Wi-Fi, ZigBee or Bluetooth
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 2310/12 The local stationary network supplying a household or a building
• CPC Class Codes: H02J 2310/60 Limiting power consumption in the network or in one section of the network, e.g. load shedding or peak shaving
• CPC Class Codes: H02J 3/00 Circuit arrangements for ac mains or ac distribution networks
• CPC Class Codes: H02J 3/003 Load forecast, e.g. methods or systems for forecasting future load demand
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: H02J 3/24 Arrangements for preventing or reducing oscillations of power in networks by control effected upon a single generator H02P9/00
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02E 40/70 Smart grids as climate change mitigation technology in the energy generation sector
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/50 Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 40/124 : using wired telecommunication networks or data transmission busses
• CPC Class Codes: Y04S 40/126 : using wireless data transmission

Abstract

A method, apparatus, system and computer program is provided for controlling an electric power system, including implementation of voltage measurement using paired t statistical analysis applied to calculating a shift in average usage per customer from one time period to another time period for a given electrical use population where the pairing process is optimized using a novel technique to improve the accuracy of the statistical measurement.

Claims

1. A control system for an electric power grid configured to supply electric power from a supply point to a plurality of consumption locations, the system comprising:

a plurality of sensors, wherein each sensor is located at a respective one of a plurality of distribution locations on the electric power grid at or between the supply point and at least one of the plurality of consumption locations, and wherein each sensor is configured to sense at least one component of a supplied electric power received at the respective consumption location and at least one of the plurality of sensors is configured to generate measurement data based on the sensed component of the power;

a controller configured to receive the measurement data from the sensors and to communicate with at least one component adjusting device to adjust a component of the electric power grid, wherein the controller is configured to operate the electric power grid in a modification on state or in a modification-off state and to determine a change in energy characteristics between the modification-on state and the modification-off state using a paired t measurement, wherein the paired t measurement determines an average shift in a mean energy usage, and wherein the modification-on state is a conservation voltage reduction (CVR) “

ON”

state and the modification off state is a CVR “

OFF”

state and wherein the paired t measurement includes a pairing process to determine a CVR factor for the electric power grid;

wherein the at least one component adjusting device is configured to adjust a component of the electric power grid based on the measurement data.

2. The control system of claim 1, wherein the modification-on state is a conservation voltage reduction (CVR) “

ON”

state and the modification-off state is a CVR “

OFF”

state.

3. The control system of claim 2, wherein the controller is configured to apply CVR to generate a CVR energy delivery parameter based on the measurement data when the controller is in the CVR “

ON”

state, but not when the controller is in the CVR “

OFF”

state.

4. The control system of claim 1, wherein the sensed component of the power is at least one of voltage and energy, and the sensed component of the power is measured on an interval basis.

5. The control system of claim 4, wherein each meter'"'"'s measurement data is averaged over the interval.

6. The system of claim 4, wherein the interval is a period of at least one of twenty-four hours, four hours, and one hour.

7. The control system of claim 1, wherein the pairing process includes measurements of CVR factor and/or conservation energy savings by season and uses at least one linear regression constant to determine the blocks of hours where consistent loads exist.

8. The control system of claim 1, wherein the paired t measurement includes a pairing process and the pairing process comprises pairing a modification “

ON”

record to a modification “

OFF”

record.

9. The control system of claim 8, wherein the modification “

OFF”

record has a predetermined first independent variable associated with the modification “

OFF”

record within a first independent variable tolerance of the first independent variable associated with the paired modification “

ON”

record.

10. The control system of claim 9, wherein the modification “

OFF”

record has a second independent variable associated with the modification “

OFF”

record within a predetermined second independent variable tolerance of the second independent variable associated with the paired modification “

ON”

record.

11. The control system of claim 1, wherein the at least one component adjusting device is configured to adjust a voltage set point value of the electrical power supplied at the supply point to the plurality of consumption locations based on the change in energy characteristics.

12. The control system of claim 1, wherein the controller is further configured to adjust the at least one component adjusting device based on the change in energy characteristics.

13. The control system of claim 1, wherein the energy characteristic is a CVR factor.

14. The control system of claim 1, wherein the energy characteristic is the energy savings.

15. The control system of claim 1, wherein the at least one component adjusting device includes a load tap change transformer configured to adjust a voltage of the electric power supplied at the supply point based on a load tap change coefficient and/or a voltage regulator that adjusts a voltage of the electric power supplied at the supply point.

16. The control system of claim 1, wherein the controller is configured to use a paired t p-factor to eliminate data having values outside of corresponding predetermined normalized ranges of values to determine measurement accuracy.

17. The control system of claim 1, wherein the controller is configured to determine the change in energy characteristic based on a first pairing variable.

18. The control system of claim 17, wherein the first variable is season, grouped hour, or customer type.

19. The control system of claim 17, wherein the controller is configured to provide a second pairing variable that is secondary to the first pairing variable, to pair the first variable values to the closest modification-off to modification-on values, and to determine a weighed scoring of the pairs based on the relative slopes of the linear relationship between the first and second respective variables.

20. The control system of claim 1, wherein the controller is configured to exclude data that is affected by non-efficiency variables.

21. The control system of claim 1, wherein the controller is further configured to receive measurement data from each sensor of a subset of the plurality of sensors, and the subset is fewer then all of the plurality of sensors receiving supplied electric power.

22. The control system of claim 21, wherein the controller is further configured to receive a signal indicating that the measured component of electric power sensed by at least one other sensor of the plurality of sensors is outside of a sensor target component band, and wherein the controller is further configured to add to the subset the at least one other sensor in response to receiving the signal indicating that the measured component of electric power sensed by the at least one other sensor is outside of the sensor target component band.

23. A non-transitory computer readable media, the computer readable media being at least one of volatile computer readable media and non-volatile computer readable media, the computer readable media having instructions for a control system for an electric power grid configured to supply electric power from a supply point to a plurality of consumption locations, the instructions comprising:

a sensor receiving instruction configured to receive measurement data from at least one of a plurality of sensors, wherein each sensor is located at a respective one of a plurality of distribution locations on the electric power grid at or between the supply point and at least one of the plurality of consumption locations, and wherein each sensor is configured to sense at least one component of a supplied electric power received at the respective distribution location, a controller instruction configured to receive the measurement data from the sensors and to communicate with at least one component adjusting device to adjust a component of the electric power grid, wherein the controller instruction is configured to operate the electric power grid in a modification-on state or in a modification-off state and to determine a change in energy characteristics between the modification-on state and the modification-off state, using a paired t measurement, wherein the paired t measurement determines an average shift in a mean energy usage, and wherein the modification-on state is a conservation voltage reduction (CVR) “

ON”

state and the modification-off state is a CVR “

OFF”

state and wherein the paired t measurement includes a pairing process to determine a CVR factor for the electric power grid;

a component adjusting instruction configured to communicate with at least one component adjusting device and to cause the at least one component adjusting device to adjust a component of the electric power grid based on the measurement data.

24. The computer readable media of claim 23, wherein the modification-on state is a conservation voltage reduction (CVR) “

ON”

state and the modification-off state is a CVR “

OFF”

state.

25. The computer readable media of claim 24, wherein the controller instruction is configured to apply CVR to generate a CVR energy delivery parameter based on the measurement data when the controller is in the CVR “

ON”

state, but not when the controller is in the CVR “

OFF”

state.

26. The computer readable media of claim 23, wherein the sensed component of the power is at least one of voltage and energy, and the sensed component of the power is measured on an interval basis.

27. The computer readable media of claim 26, wherein each meter'"'"'s measurement data is averaged over the interval.

28. The system of claim 26, wherein the interval is a period of at least one of twenty-four hours, four hours, and one hour.

29. The computer readable media of claim 23, wherein the pairing process includes measurements of CVR factor and/or conservation energy savings by season and uses at least one linear regression constant to determine the blocks of hours where consistent loads exist.

30. The computer readable media of claim 23, wherein the paired t measurement includes a pairing process and the pairing process comprises pairing a modification “

ON”

record to a modification “

OFF”

record.

31. The computer readable media of claim 30, wherein the modification “

OFF”

record has a predetermined first independent variable associated with the modification “

OFF”

record within a first independent variable tolerance of the first independent variable associated with the paired modification “

ON”

record.

32. The computer readable media of claim 31, wherein the modification “

OFF”

record has a second independent variable associated with the modification “

OFF”

record within a predetermined second independent variable tolerance of the second independent variable associated with the paired modification “

ON”

record.

33. The computer readable media of claim 23, wherein the at least one component adjusting device is configured to adjust a voltage set point value of the electrical power supplied at the supply point to the plurality of consumption locations based on the change in energy characteristics.

34. The computer readable media of claim 23, wherein the controller instruction is further configured to adjust the at least one component adjusting device based on the change in energy characteristics.

35. The computer readable media of claim 23, wherein the energy characteristic is a CVR factor.

36. The computer readable media of claim 23, wherein the energy characteristic is the energy savings.

37. The computer readable media of claim 23, wherein the at least one component adjusting device includes a load tap change transformer configured to adjust a voltage of the electric power supplied at the supply point based on a load tap change coefficient and/or a voltage regulator that adjusts a voltage of the electric power supplied at the supply point.

38. The computer readable media of claim 23, wherein the controller instruction is configured to use a paired t p-factor to eliminate data having values outside of corresponding predetermined normalized ranges of values to determine measurement accuracy.

39. The computer readable media of claim 23, wherein the controller instruction is configured to determine the change in energy characteristic based on a first pairing variable.

40. The computer readable media of claim 39, wherein the first variable is season, grouped hour, or customer type.

41. The computer readable media of claim 39, wherein the controller instruction is configured to provide a second pairing variable that is secondary to the first pairing variable, to pair the first variable values to the closest modification-off to modification-on values, and to determine a weighed scoring of the pairs based on the relative slopes of the linear relationship between the first and second respective variables.

42. The computer readable media of claim 23, wherein the controller instruction is configured to exclude data that is affected by non-efficiency variables.

43. The computer readable media of claim 23, wherein the controller instruction is further configured to receive measurement data from each sensor of a subset of the plurality of sensors, and the subset is fewer then all of the plurality of sensors receiving supplied electric power.

44. The computer readable media of claim 43, wherein the controller instruction is further configured to receive a signal indicating that the measured component of electric power sensed by at least one other sensor of the plurality of sensors is outside of a sensor target component band, and wherein the controller instruction is further configured to add to the subset the at least one other sensor in response to receiving the signal indicating that the measured component of electric power sensed by the at least one other sensor is outside of the sensor target component band.