Determining electric grid endpoint phase connectivity

• US 9,263,915 B2
• Filed: 05/25/2012
• Issued: 02/16/2016
• Est. Priority Date: 09/05/2008
• Status: Active Grant

• Current Assignee: Itron Networked Solutions, Inc. (Itron, Inc.)
• Original Assignee: Silver Spring Networks, Inc. (Itron, Inc.)
• Inventors: Vaswani, Raj, van Greunen, Jana, Gostrer, Alexander
• Primary Examiner(s): Baldridge, Benjamin M
• Application Number:
  US13/480,950
• Publication Number:
  US 20120232844A1
• Time in Patent Office: 1,362 Days
• Field of Search: 324/66
• US Class Current: 1/1
• CPC Class Codes: G01R 29/18 Indicating phase sequence; Indicating synchronism
• CPC Class Codes: H02J 13/00009 using pulsed signals
• CPC Class Codes: H02J 13/0001 using modification of a parameter of the network power signal
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 3/00 Circuit arrangements for ac mains or ac distribution networks
• CPC Class Codes: H02J 3/002 Flicker reduction, e.g. compensation of flicker introduced by non-linear load
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/52 Outage or fault management, e.g. fault detection or location
• CPC Class Codes: Y04S 40/121 using the power network as support for the transmission

Abstract

The service phase of the electrical connection to a customer endpoint device located within a power distribution system is determined by various techniques. At the feeder level, the system may be programmed to induce disturbances, thereby causing missed zero crossings at the customer endpoint devices. The pattern of these disturbances is a controlled one, designed specifically to avoid causing noticeable disruption even to sensitive devices, but to be unusual enough that it is statistically unlikely to be naturally occurring. The monitoring of the zero crossing information is used to determine the phase of the service line to the customer endpoint devices.

Claims

1. A method of determining a service phase of an endpoint device in a power distribution system, the method comprising:

sending a message to a point in the power distribution system requesting a power line event affecting power quality on one of a plurality of power distribution phases of a feeder line to customer sites;

receiving a report from each of a plurality of endpoint devices at respective customer sites indicating that the requested power line event was detected by each of the plurality of endpoint devices; and

based on the received reports, mapping at least one endpoint device that reported the detection of the power line event to the respective phase on which the power line event was created, thus identifying which of the plurality of phases the feeder line of the endpoint device is serviced by.

2. The method of claim 1, wherein the point in the power distribution system to which the message is sent is a substation.

3. The method of claim 1, wherein the plurality of endpoint devices are programmed to detect, log, and report power line events.

4. The method of claim 1, wherein the plurality of endpoint devices detect the power line event by monitoring missed zero crossings in alternating current power within a predetermined time period.

5. The method of claim 1, wherein the power line event is induced serially on each phase of the feeder line at a given time for a predetermined period of time.

6. The method of claim 5, wherein the mapping of the endpoint device is performed at a back office server having information pertaining to the power line event being induced on a particular phase, and based on the reports received from the end-point devices, the back office server links the end-point device reporting the power line event at the given time to the particular phase.

7. The method of claim 1, wherein a single power line event is detected when the endpoint device measures a zero-crossing for a period of time that is less than a predetermined maximum time period and longer than a predetermined minimum time period.

8. The method of claim 7, wherein the maximum time period is determined so that a device, to which the power is supplied, avoids reacting to the power line event as a loss of power.

9. The method of claim 7, wherein duration of a power line event for the predetermined minimum time period causes the endpoint devices to measure zero-crossing data, and send a report containing the measured data.

10. The method of claim 1, wherein the power line event is a temporary power interruption.