APPARATUS FOR DECENTRALIZED COORDINATED VOLT/VAR CONTROL (CVVC)

• US 20130024032A1
• Filed: 07/19/2011
• Published: 01/24/2013
• Est. Priority Date: 07/19/2011
• Status: Active Grant

• Current Assignee: GE Digital Holdings LLC (GE Aerospace)
• Original Assignee: General Electric Company
• Inventors: Vukojevic, Aleksandar, Milosevic, Borka
• Granted Patent: US 9,099,890 B2
• Time in Patent Office: Days
• US Class Current: 700/291
• CPC Class Codes: H02J 13/00001 characterised by the display of information or by user interaction, e.g. supervisory control and data acquisition systems [SCADA] or graphical user interfaces [GUI]
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• 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 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 3/1828 with stepwise control, the possibility of switching in or out the entire compensating arrangement not being considered as stepwise control
• 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 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/22 Flexible AC transmission systems [FACTS] or power factor or reactive power compensating or correcting units
• CPC Class Codes: Y04S 10/40 Display of information, e.g. of data or controls
• 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 system for enhancing decentralized coordinated Volt/Var control (CVVC) includes a memory device configured to store a plurality of operational measurements of an electric distribution system. The electric distribution system includes a plurality of capacitive devices. The system also includes a processor coupled in communication with the memory device. The processor is programmed to determine a plurality of potential configurations for the plurality of capacitive devices. The processor is also programmed to determine a priority of switching of each of the plurality of capacitive devices as a function of at least one of at least one actual voltage measurement of the electric distribution system, at least one power factor determination of the electric distribution system, at least one voltage parameter, at least one power factor parameter, and an availability of each of the capacitive devices.

Claims

1. A system for enhancing decentralized coordinated Volt/Var control (CVVC), said system comprising:

a memory device configured to store a plurality of operational measurements of an electric distribution system, the electric distribution system includes a plurality of capacitive devices; and

a processor coupled in communication with said memory device, said processor programmed to;

determine a plurality of potential configurations for the plurality of capacitive devices; and

determine a priority of switching of each of the plurality of capacitive devices as a function of at least one of;

at least one actual voltage measurement of the electric distribution system;

at least one power factor determination of the electric distribution system;

at least one voltage parameter;

at least one power factor parameter; and

an availability of each of the capacitive devices.

2. A system in accordance with claim 1, wherein the plurality of potential configurations for the plurality of capacitive devices comprises a plurality of capacitor switching combinations (CSCs), wherein each CSC comprises those capacitive devices available for switching as a function of at least one of capacitor switch timing devices and capacitor switch counting devices.

3. A system in accordance with claim 2, further comprising at least one feasible CSC, wherein said at least one feasible CSC comprises at least one capacitive device that facilitates maintaining at least one voltage value of the electric distribution system within predetermined parameters as a function of:

when the at least one capacitive device is switched from an ON status to an OFF status; and

when the at least one capacitive device is switched from an OFF status to an ON status.

4. A system in accordance with claim 2, wherein said at least one power factor determination of the electric distribution system comprises a power factor determination for the low side of a transformer associated with individually operating each of the plurality of capacitive devices.

5. A system in accordance with claim 2, wherein said processor is further programmed to eliminate a CSC from consideration as a feasible CSC as a function of at least one of:

at least one CSC comprising at least one capacitive device that induces a decrease of a voltage of the electric distribution system below a predetermined parameter upon a change of status of the at least one capacitive device; and

at least one CSC comprising at least one capacitive device that induces an increase of a voltage of the electric distribution system above a predetermined parameter upon a change of status of the at least one capacitive device.

6. A system in accordance with claim 2, wherein said processor is further programmed to eliminate CSCs from consideration as a feasible CSC as a function of at least one of:

at least one CSC comprising at least one capacitive device that induces a change of a power factor of the electric distribution system outside of a predetermined range defined by predetermined parameters upon a change of status of the at least one capacitive device; and

a first CSC comprising a first number of switches, a second CSC comprising a second number of switches, the first number of switches is greater than the second number of switches.

7. A system in accordance with claim 1, wherein said processor is further programmed to:

switch the at least one capacitive device from an OFF status to an ON status; and

switch the at least one capacitive device from an ON status to an OFF status.

8. A system for enhancing decentralized coordinated Volt/Var control (CVVC), said system comprising:

a memory device configured to store a plurality of actual measurements of an electric distribution system, the electric distribution system includes at least one feeder that includes a plurality of capacitive devices; and

a processor coupled in communication with said memory device, said processor programmed to;

determine an actual power factor for the at least one feeder;

determine if the actual power factor for the at least one feeder is within predetermined feeder power factor parameters;

determine a priority of each capacitive device available for switching from the plurality of capacitive devices as a function of a voltage flattening effect on the feeder;

determine a range between predetermined feeder reactive power parameters;

determine a range of differential reactive power values between actual reactive power on the at least one feeder and a target value for reactive power on the at least one feeder;

determine a differential reactive power value for each available capacitive device; and

command at least available capacitive device to switch.

9. A system in accordance with claim 8, wherein said processor is further programmed to determine the status of each available capacitive device as an OFF status or an ON status.

10. A system in accordance with claim 8, wherein said processor is further programmed to determine a range of reactive power differential values for the at least one feeder as a function of at least one of the predetermined power factor parameters.

11. A system in accordance with claim 10, wherein said processor is further programmed to determine if the differential reactive power value for each available capacitive device is within the range of reactive power differential values for the at least one feeder.

12. A system in accordance with claim 11, wherein said processor is further programmed to:

determine if no available capacitive devices have a differential reactive power value within the range of reactive power differential values for the at least one feeder; and

determine if at least one available capacitive device has a differential reactive power value within the range of reactive power differential values for the at least one feeder.

13. A system in accordance with claim 11, wherein said processor is further programmed to determine which capacitive device of the available capacitive devices provides the lowest determined differential feeder reactive power value when switched.

14. A system for enhancing decentralized coordinated Volt/Var control (CVVC), said system comprising:

a memory device configured to store a plurality of operational measurements of an electric distribution system, the electric distribution system includes a substation, a transformer, a plurality of feeders coupled to the transformer, and a plurality of capacitive devices in each feeder; and

a processor coupled in communication with said memory device, said processor programmed to;

determine an actual power factor for a low side of the transformer and an actual power factor for each feeder of the plurality of feeders;

determine if the actual power factor for the low side of the transformer is within predetermined transformer low side power factor parameters;

determine a forecasted power factor for each of the plurality of feeders as a function of a status and an availability of the capacitive devices in each feeder;

determine if each of the actual power factors for each feeder of the plurality of feeders and the forecasted power factors for each feeder of the plurality of feeders are within predetermined feeder power factor parameters;

determine a forecasted power factor for the low side of the transformer as a function of the status and the availability of the capacitive devices in each feeder;

determine if each of the actual power factor for the low side of the transformer and the forecasted power factors for the low side of the transformer are within predetermined transformer low side power factor parameters; and

determine a switching priority for each of the plurality capacitive devices as a function of a comparison between the power factors determined for the plurality of feeders and the power factors determined for the low side of the transformer.

15. A system in accordance with claim 14, wherein said processor is further programmed to determine a number of capacitive devices associated with the substation and positioned upstream of the plurality of feeders.

16. A system in accordance with claim 15, wherein said processor is further programmed to determine a forecasted power factor for the low side of the transformer for every capacitive device associated with the substation.

17. A system in accordance with claim 16, wherein said processor is further programmed to select at least one of the substation capacitive devices for changing the actual value of the power factor for the low side of the transformer to an actual value that is within the predetermined transformer low side power factor parameters.

18. A system in accordance with claim 14, wherein said processor is further programmed to:

determine an actual power factor value for each feeder of the plurality of feeders;

determine a target feeder power factor value for each feeder of the plurality of feeders; and

determine a feeder power factor error value between each target feeder power factor value and each actual feeder power factor value.

19. A system in accordance with claim 18, wherein said processor is further programmed to prioritize the plurality of feeders with respect to a magnitude of the feeder power factor error values.

20. A system in accordance with claim 14, wherein the transformer further includes a high side and a low side, wherein said processor is further programmed to determine and control an actual power factor on the high side of the transformer.