Control method and apparatus for power distribution network

• US 5,784,237 A
• Filed: 11/29/1996
• Issued: 07/21/1998
• Est. Priority Date: 11/29/1996
• Status: Expired due to Term

• Current Assignee: S&C Electric Company
• Original Assignee: S&C Electric Company
• Inventors: Velez, Andrew M.
• Primary Examiner(s): Gaffin, Jeffrey A.
• Assistant Examiner(s): JACKSON, STEPHEN W
• Application Number:
  US08/758,406
• Time in Patent Office: 599 Days
• Field of Search: 361/62, 361/63, 361/64, 361/66, 361/115
• US Class Current: 361/62
• CPC Class Codes: H02H 7/262 involving transmissions of switching or blocking orders

Abstract

A control method and apparatus is provided for isolating network faults via the communication between neighboring network locations and the control of sectionalizing switches at the network locations. Control apparatus is provided at particular network locations which responds to detected fault conditions and communicates the detected fault condition to the control apparatus at neighboring network locations. The appropriate control apparatus, in response to the information received from neighboring network locations, opens a sectionalizing switch to isolate the fault condition. In one particular arrangement, each control apparatus that detects a fault condition sends a signal to appropriate source-side, neighboring control apparatus to inhibit the source-side control apparatus from opening their respective sectionalizing switches. Further, any control apparatus that detected a fault condition and that does not receive an inhibiting signal, controls its sectionalizing switch to open. Inn a specific arrangement, the control apparatus that opens its sectionalizing switch also sends a signal to predetermined neighboring load-side control apparatus to open their sectionalizing switches, so as to prevent feeding into a fault condition after network restoration via a different path or source.

Claims

1. An arrangement for isolating a faulted section of a power distribution network comprising:

a plurality of control apparatus located at particular points in the distribution network, each of said plurality of control apparatus comprising detecting means for detecting fault conditions, first means responsive to said detecting means for communicating with predetermined source-side and load-side control apparatus in the power distribution network, and second means responsive to said detecting means and communications received from other of said plurality of control apparatus for providing a sectionalizing switch-opening signal to an associated sectionalizing switch and adjacent load-side control apparatus, said second means further comprising third means for providing an inhibit signal to predetermined source-side control apparatus so as to prevent the source-side control apparatus from providing a sectionalizing switch-opening signal.

2. The method of claim 1 wherein the control apparatus is responsive to the direction of current through its respective sectionalizing switch.

3. A method for isolating a faulted section of an electrical power distribution network which includes a plurality of control apparatus at predetermined locations along the power distribution network each of which includes provisions for detecting fault conditions and selectively controlling the opened or closed status of a respective sectionalizing switch, the method comprising the steps of:

detecting a fault condition by each of the control apparatus on the source side of the fault condition;

each of the control apparatus that detects a fault condition communicating an inhibit signal to predetermined source-side control apparatus so as to prevent the source-side control apparatus from opening the sectionalizing switch; and

each of the control apparatus that detects a fault condition and that does not receive an inhibit signal controlling the opening of its respective sectionalizing switch.

4. The method of claim 3 further comprising the step of sensing by each control apparatus the direction of current through its respective sectionalizing switch.

5. The method of claim 4 further comprising the step of sending a sectionalizing switch-opening signal to predetermined load-side control apparatus by the control apparatus that detects a fault condition and that does not receive an inhibit signal.

6. The method of claim 5 further comprising the step of storing within each control apparatus information representing the predetermined source-side and load-side control apparatus.

7. A method of isolating a faulted section of a power distribution network having sectionalizing apparatus with a respective associated switch at predetermined locations in the power distribution network, each of the sectionalizing apparatus detecting fault conditions including the direction of current, being capable of communicating with one or more predetermined neighboring sectionalizing apparatus, and being responsive to received open and open-inhibit signals, the method comprising the steps of:

sending an open-inhibit signal by each sectionalizing apparatus that detects a fault condition to its respective predetermined neighbors that are determined to be upstream of the fault condition;

each sectionalizing switch that detects a fault condition opening its respective associated switch a predetermined time interval after the detection of a fault condition unless an open-inhibit signal is received; and

each sectionalizing switch that detects a fault condition and does not receive an open-inhibit signal sending an open signal to the predetermined neighbors that are determined to be downstream of the fault condition.