Systems and methods for stabilizer control

• US 10,732,656 B2
• Filed: 08/22/2016
• Issued: 08/04/2020
• Est. Priority Date: 08/24/2015
• Status: Active Grant

• Current Assignee: Dominion Energy, Inc.
• Original Assignee: Dominion Energy, Inc.
• Inventors: Tyler, Stephen J., Powell, Phillip W.
• Primary Examiner(s): Saavedra, Emilio J
• Application Number:
  US15/243,217
• Publication Number:
  US 20170060161A1
• Time in Patent Office: 1,443 Days
• Field of Search: 700295
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence
• CPC Class Codes: G05B 19/0428 Safety, monitoring G05B19/0423 takes precedence
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy
• CPC Class Codes: H02J 3/16 by adjustment of reactive power
• CPC Class Codes: H02J 3/28 Arrangements for balancing of the load in a network by storage of energy
• CPC Class Codes: H02J 3/38 Arrangements for parallely feeding a single network by two or more generators, converters or transformers
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/388 Islanding, i.e. disconnection of local power supply from the network
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 40/30 Reactive power compensation
• CPC Class Codes: Y02E 40/70 Smart grids as climate change mitigation technology in the energy generation sector
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin
• 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

Abstract

A method, apparatus, system and computer program is provided for controlling an electric power system, including implementation of a voltage control and conservation (VCC) system used to optimally control the independent voltage and capacitor banks using a linear optimization methodology to minimize the losses in the EEDCS and the EUS. An energy validation process system (EVP) is provided which is used to document the savings of the VCC and an EPP is used to optimize improvements to the EEDCS for continuously improving the energy losses in the EEDS. The EVP system measures the improvement in the EEDS a result of operating the VCC system in the “ON” state determining the level of energy conservation achieved by the VCC system. In addition the VCC system monitors pattern recognition events and compares them to the report-by-exception data to detect HVL events. If one is detected the VCC optimizes the capacity of the EEDS to respond to the HVL events by centering the piecewise linear solution maximizing the ability of the EDDS to absorb the HVL event. The VCC stabilizer function integrates voltage data from AMI meters and assess the state of the grid and initiates appropriate voltage control actions to hedge against predictable voltage risks.

Claims

1. A control system for an electric power grid configured to supply electric power from a supply point to a plurality of user 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 grid at or between the supply point and at least one of the plurality of user locations, wherein each sensor is configured to sense a component of the supplied electric power at the respective distribution location and to generate measurement data based on the sensed component of the power, and wherein at least one of the plurality of sensors is associated with a distribution location having at least one distributed energy resource and is adapted to measure an amount of distributed power generation by the at least one distributed energy resource, wherein the at least one distributed energy resource is different than the supply point;

a controller configured to determine a distributed energy resource injection based on the measurement data, to modify a controller target value of the supplied electric power based on the distributed energy resource injection, and to generate an energy delivery parameter based on the controller target value of the supplied electric power and the measurement data received from the sensors including the amount of distributed power generation, wherein the distributed energy resource injection is the amount of distributed power generation, the controller target value of the supplied electric power is a controller voltage target value, and the controller is configured to raise the controller target voltage value within a predetermined range of voltage values as the amount of distributed power generation increases; and

a component adjusting device configured to adjust a component of the electric power grid at the supply point in response to the energy delivery parameter.

2. The system of claim 1, wherein the component of the supplied electric power is voltage and the controller target value of the supplied electric power is a controller target voltage band having a voltage set point and a voltage deviation range.

3. The system of claim 1, wherein the controller target voltage value of the supplied electric power is lowered as the amount of distributed power generation decreases.

4. The system of claim 1, wherein the distributed energy resource includes an inverter communicatively connected to the controller.

5. The system of claim 1, wherein the controller is further configured to add the measurement data from the plurality of sensors to a load profile, to assess the state of the grid, and to generate the energy deliver parameter to hedge against predictable voltage risk.

6. The 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, wherein the subset includes more than one and substantially fewer than all of the plurality of sensors, and to generate the energy delivery parameter based on the measurement data received from the subset and the controller target value of the supplied electric power.

7. The system of claim 6, wherein the subset is chosen based on a characteristic of the sensor.

8. The system of claim 7, wherein the characteristic is that the sensors are within a specific block of the grid.

9. The system of claim 7, wherein the characteristic is that the sensors are within a specific zone of the grid.

10. The system of claim 4, wherein the at least one of the plurality of sensors associated with the distribution location having at least one distributed energy resource is within a same block as the inverter.

11. The system of claim 6, wherein the controller is further configured to add to the subset at least one other sensor in response to receiving a signal indicating that a measured component of electric power sensed by the at least one other sensor is outside of the controller target value of the supplied electric power and to de-select at least one of the sensors in the subset when adding the at least one other sensor to the subset.

12. The system of claim 4, wherein the inverter is configured to modify VAR absorption or production in response to the controller.

13. The system of claim 12, wherein the inverter is configured to modify VAR absorption or production based on a power factor.

14. The system of claim 4, wherein the component of the supplied electric power is volts-amperes reactive (VAR), and the control system is configured to modify VAR absorption or production by the inverter to maintain a desired voltage at the inverter.

15. The system of claim 13, wherein the power factor is adjusted based on a proactive schedule.

16. The system of claim 1, wherein the distributed energy resource includes at least one of distributed storage, photovoltaic generation, and inverters.

17. The system of claim 1, wherein the component of the supplied electric power is at least one of phase angle, current angle, power factor, VAR and power vectors.

18. The system of claim 1, wherein the component adjusting device is configured to vary at least one of a phase angle, a current angle, a power factor, a VAR and a power vector.

19. The system of claim 1, wherein the controller is configured to modify the controller target value of the supplied electric power based on the distributed, energy resource injection and a pattern of voltage changes at the plurality of sensors.

20. The system of claim 1, wherein the controller is further configured to determine a complex voltage based on measurement data from the plurality of sensors.

21. The system of claim 1, wherein the controller target value of the supplied electric power has first upper and lower limits for a first control mode and has second upper and lower limits for a second control mode;

and wherein the controller selects either the first or second modes based on the measurement data received from the sensors.

22. The system of claim 21, wherein the first control mode is an active distributed generation control mode and the second control mode is an inactive distributed generation control mode.

23. A method for controlling electric power supplied through an electric power grid to a plurality of distribution locations located at or between a supply point and at least one user location, each of the plurality of distribution locations including at least one sensor configured to sense a component of the supplied electric power received by the sensor at the respective distribution location and to generate measurement data based on the sensed component, and at least one of the plurality of sensors is associated with a distribution location having at least one distributed energy resource, wherein the at least one distributed energy resource is different than the supply point, the method comprising:

determining a distributed energy resource injection based on the measurement data, wherein the at least one of the plurality of sensors is adapted to measure an amount of distributed power generation by the at least one distributed energy resource and the distributed energy resource injection is the amount of distributed power generation;

modifying a controller target value of the supplied electric power based on the distributed energy resource injection, wherein the controller target value of the supplied electric power is a controller voltage target value, and modifying a controller target value includes raising the controller target voltage value within a predetermined range of voltage values as the amount of distributed power generation increases;

generating an energy delivery parameter based on the controller target value of the supplied electric power and the measurement data received from the sensors; and

operating a component adjusting device configured to adjust a component of the electric power grid at the supply point in response to the energy delivery parameter.

24. The method of claim 23, wherein the component of the supplied electric power is voltage and the controller target value of the supplied electric power is a controller target voltage band having a voltage set point and a voltage deviation range.

25. The method of claim 23, wherein the controller target voltage value of the supplied electric power is lowered as the amount of distributed power generation decreases.

26. The method of claim 23, wherein the distributed energy resource includes an inverter communicatively connected to the controller.

27. The method of claim 23 further comprising adding the measurement data from the plurality of sensors to a load profile, to assess the state of the grid, and to generate the energy deliver parameter to hedge against predictable voltage risk.

28. The method of claim 26, wherein at least one of the plurality of sensors associated with the distribution location having at least one distributed energy resource is within a same block as the inverter.

29. The method of claim 26, wherein component of the supplied electric power is volts-amperes reactive (VAR), and the method further comprises modifying the VAR absorption or production of the inverter.

30. The method of claim 29, wherein the inverter is configured to modify VAR absorption or production based on a power factor.

31. The method of claim 26, wherein the method further comprises modifying VAR absorption or production by the inverter to maintain a desired voltage at the inverter.

32. The method of claim 30, wherein the power factor is adjusted based on a proactive schedule.

33. The method of claim 23, wherein the distributed energy resource includes at least one of distributed storage, photovoltaic generation, and inverters.

34. The method of claim 23, wherein the controller target value of the supplied electric power is modified based on the distributed energy resource injection and a pattern of voltage changes at the plurality of sensors.

35. The method of claim 23, wherein the controller target value of the supplied electric power has first upper and lower limits for a first control mode and has second upper and lower limits for a second control mode;

and wherein the first or second modes are selected based on the measurement data received from the sensors.

36. The method of claim 35, wherein the first control mode is an active distributed generation control mode and the second control mode is an inactive distributed generation control mode.