SYSTEM AND METHOD FOR CONTROLLING VOLTAGE ON A DISTRIBUTION FEEDER

• US 20130024040A1
• 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 8,639,389 B2
• Time in Patent Office: Days
• US Class Current: 700/293
• CPC Class Codes: H02J 3/16 by adjustment of reactive power
• 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

Abstract

A system for controlling voltage on a distribution feeder includes a plurality of capacitor banks that can be connected to or disconnected from the distribution feeder. A first bank is configured to connect to the distribution feeder when a first voltage is below a first lower threshold value and to connect to the distribution feeder when the first voltage is above a first upper threshold value. The first upper threshold and first lower threshold are determined based off an operational set point. The system further includes a sensor configured to measure the first voltage and a controller in operable communication with the plurality of capacitor banks configured to determine the operational state of the first and second capacitor banks and, based on the first voltage, send a first instruction to the first capacitor bank, the first instruction causing the capacitor bank to vary the operational set point.

Claims

1. A method for controlling voltage on a distribution feeder, the distribution feeder including a plurality of capacitor banks associated with the distribution feeder, the plurality of capacitor banks including a first capacitor bank and a second capacitor bank, the first capacitor bank being configured to connect to the distribution feeder when a first voltage is below a first lower threshold value and to disconnect from the distribution feeder when the first voltage is above a first upper threshold value, the first upper threshold value and first lower threshold value being determined based on an operational set point of the first capacitor bank, the method comprising:

determining at a computing device the operational state of the first and second capacitor banks;

measuring the first voltage with a voltage sensor associated with the first capacitor bank;

determining whether the first capacitor bank should be connected to or disconnected from the distribution feeder; and

sending a first instruction to the first capacitor bank, the first instruction causing the first capacitor bank to vary its operational set point.

2. The method of claim 1, wherein the operational state is one of connected or not connected.

3. The method of claim 2, wherein determining whether the first capacitor bank should be connected to or disconnected from the distribution feeder includes:

determining that operational state is connected; and

determining that disconnecting the first capacitor bank will flatten a voltage profile of the distribution feeder.

4. The method of claim 3, sending includes sending the first instruction such that it causes the first capacitor bank to increase its operational set point.

5. The method of claim 2, wherein determining whether the first capacitor bank should be connected to or disconnected from the distribution feeder includes:

determining that operational state is disconnected; and

determining that connecting the first capacitor bank will flatten a voltage profile of the distribution feeder.

6. The method of claim 5, wherein sending includes sending the first instruction such that it causes the first capacitor bank to decrease its operational set point.

7. The method of claim 1, further comprising:

after sending the first instruction to the first capacitor bank to cause it to vary its operational set point, sending a hold instruction to one or more of the plurality of capacitor banks that disallows them from changing operational status;

determining a lower input voltage for the distribution feeder; and

sending a second instruction to the first capacitor bank to decrease its operational set point.

8. The method of claim 7, wherein the lower input voltage is between 126 and 114 volts.

9. The method of claim 7, wherein the lower input voltage is lower than a current input voltage by a voltage difference and the second instruction causes the first capacitor bank to lower its operational set point in an amount equal to the voltage difference.

10. The method of claim 7, further comprising:

sending a release instruction to the one or more of the plurality of capacitor banks that allows them to change operational status.

11. A system for controlling voltage on a distribution feeder, the system comprising:

a plurality of capacitor banks that can be connected to or disconnected from the distribution feeder, the plurality of capacitor banks including a first capacitor bank and a second capacitor bank, the first capacitor bank being configured to connect to the distribution feeder when a first voltage is below a first lower threshold value and to disconnect from the distribution feeder when the first voltage is above a first upper threshold value, the first upper threshold and first lower threshold being determined based on an operational set point;

a sensor configured to measure the first voltage; and

a controller in operable communication with the plurality of capacitor banks configured to determine the operational state of the first and second capacitor banks and, based on the first voltage, send a first instruction to the first capacitor bank, the first instruction causing the capacitor bank to vary the operational set point.

12. The system of claim 11, wherein the controller is configured to determine whether the first capacitor bank should be connected to or disconnected from the distribution feeder based on a determination that an operational state of the first capacitor bank is connected and a determination that disconnecting the first capacitor bank will flatten a voltage profile of the distribution feeder.

13. The system of claim 12, wherein the controller is configured to send the first instruction such that it causes first the capacitor bank to increase the operational set point.

14. The system of claim 11, wherein the controller is configured to determine whether the first capacitor bank should be connected to or disconnected from the distribution feeder based on a determination that an operational state of the first capacitor bank is disconnected and a determination that connecting the first capacitor bank will flatten a voltage profile of the distribution feeder.

15. The system of claim 14, wherein the controller is configured to send the first instruction such that it causes first the capacitor bank to decrease the operational set point.