AUTOMATED SYNCHRONIZATION OF DATA BETWEEN ELECTRICAL GRIDS

• US 20100111112A1
• Filed: 10/31/2008
• Published: 05/06/2010
• Est. Priority Date: 10/31/2008
• Status: Active Grant

• Current Assignee: Schneider Electric USA, Inc. (Schneider Electric SE)
• Original Assignee: Square D Company (Schneider Electric SE)
• Inventors: Bickel, Jon A.
• Granted Patent: US 8,467,985 B2
• Time in Patent Office: Days
• US Class Current: 370/503
• CPC Class Codes: G06F 16/2358 Change logging, detection, and notification replication G06F16/27
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor

Abstract

A method and system of automatically correlating data measured by monitoring devices that monitor first and second electrical grids. The second electrical grid producing alternating current signals that are electrically isolated from alternating current signals produced by the first electrical grid. An example power monitoring device includes a controller, a first monitoring device interface and a second monitoring device interface. The first monitoring device interface is coupled to a first monitoring device in the first electrical grid and the second monitoring device interface is coupled to a second monitoring device in the second electrical grid. A first counter stores data counts of occurrences from the first electrical grid. A second counter stores data counts of occurrences from the second electrical grid. A synchronization monitoring algorithm automatically synchronizes the first and second counters by associating a data count from the first counter with a data count from the second counter with a time from either the first or second grid corresponding to the occurrence of an event on either the first or the second electrical grid or both.

Claims

1. A method of automatically associating data measured by monitoring devices that monitor independent electrical grids, comprising:

receiving, at a master synchronization device, first signal data from a first set of monitoring devices that are monitoring a first electrical grid, the first signal data representing at least frequency variations measured by respective ones of the first monitoring devices for a predetermined number of occurrences;

automatically synchronizing, in the master synchronization device, the frequency variations measured by each of the first monitoring devices and producing a first occurrence counter that counts a periodic occurrence in the synchronized frequency variations associated with the first monitoring devices;

receiving, at the master synchronization device, second signal data from a second set of monitoring devices that are monitoring a second electrical grid, the second electrical grid producing alternating current signals that are electrically isolated from alternating current signals produced by the first electrical grid, the second signal data representing at least frequency variations measured by respective ones of the second monitoring device for a predetermined number of occurrences;

automatically synchronizing, in the master synchronization device, the frequency variations measured by each of the second monitoring devices and producing a second occurrence counter that counts a periodic occurrence in the synchronized frequency variations associated with the second monitoring devices;

automatically associating, in the master synchronization device, a first count of the first occurrence counter with a second count of the second occurrence counter, wherein the first count and the second count temporally correspond to an electrical event in the first electrical grid or the second electrical grid or both.

2. The method of claim 1, wherein the first electrical grid or the second electrical grid is defined as part of an electrical utility grid interconnection.

3. The method of claim 1, wherein the alternating current produced by the first electrical grid is electrically isolated from the alternating current produced by the second electrical grid via an intervening uninterruptible power supply, a motor-generator set, or a diesel-generator set.

4. The method of claim 1, wherein the number of occurrences associated with the first monitoring devices is a number of cycles of the alternating current signals produced by the first electrical grid, and the number of occurrences associated with the second monitoring devices is a number of cycles of the alternating current signals produced by the second electrical grid.

5. The method of claim 1, wherein the first and second electrical grids both supply alternating current signals to a data center.

19. The method of claim 1, further comprising:

receiving, at the master synchronization device, a first time from the first electrical grid and a second time from the second electrical grid; and

associating the first time with the second time based on the association of the first count with the second count.

6. A power monitoring device for associating data between a first and second electrical grid, the second electrical grid producing alternating current signals that are electrically isolated from alternating current signals produced by the first electrical grid, the power monitoring device comprising:

a controller;

a first monitoring device interface coupled to a first monitoring device in the first electrical grid;

a second monitoring device interface coupled to a second monitoring device in the electrical utility grid;

a first counter corresponding to data counts of occurrences from the first electrical grid;

a second counter corresponding to data counts of occurrences from the second electrical grid; and

a synchronization monitoring algorithm automatically synchronizing the first and second counters by associating a data count from the first counter with a data count from the second counter with a time from either the first or second electrical grid corresponding to the occurrence of an event on either the first or the second electrical grid or both.

7. The device of claim 6, wherein said first monitoring and second monitoring devices are intelligent electronic devices.

8. The device of claim 6, wherein one of the electrical grids is defined as part of an electrical utility grid interconnection.

9. The device of claim 6, wherein the alternating current produced by the first electrical grid is electrically isolated from the alternating current produced by the second electrical grid via an intervening uninterruptible power supply, a motor-generator set, or a diesel-generator set.

10. The device of claim 6, wherein the date counts of occurrences from the first electrical grid is a number of cycles of the alternating current signals produced by the first electrical grid, and the data counts of occurrences from the second electrical grid is a number of cycles of the alternating current signals produced by the second electrical grid.

11. The device of claim 10, wherein the number of cycles associated with the first electrical grid represents a number of zero crossings by a current or voltage signal monitored by the first monitoring device in the first electrical grid.

12. The device of claim 6, wherein the first or second monitoring device interface are mounted on a card module detachable from the controller, and the master synchronization algorithm is stored in a memory.

13. The device of claim 6, wherein the first and second monitoring device interface are mounted on a card module detachable from the controller, and the master synchronization algorithm is stored in a memory coupled to the controller.

14. A machine readable medium having stored thereon instructions for associating data measured from a first and a second electrical grid, the second electrical grid producing alternating current signals that are electrically isolated from alternating current signals produced by the first electrical grid, comprising machine executable code, which when executed by at least one machine, causes the machine to:

receive first signal data from a first monitoring device monitoring the first electrical grid, the first signal data representing frequency variations measured by the first monitoring device for a predetermined number of occurrences;

receive second signal data from a second monitoring device monitoring the second electrical grid, the second signal data representing at least frequency variations measured by the second monitoring device for a predetermined number of occurrences;

determine a first occurrence count corresponding to one of the frequency variations measured by the first monitoring device;

determine a second occurrence count corresponding to the one of the frequency variations measured by the second monitoring device; and

associate the first occurrence count with the second occurrence count based on a time measurement of an event occurring in either the first or second electrical grid or both.

15. The machine readable medium of claim 14, wherein the first electrical grid or the second electrical grid is defined as part of an electrical utility grid interconnection.

16. The machine readable medium of claim 14, wherein the alternating current produced by the first electrical grid is electrically isolated from the alternating current produced by the second electrical grid via an intervening uninterruptible power supply, a motor-generator set, or a diesel generator set.

17. The machine readable medium of claim 14, wherein the number of occurrences associated with the first monitoring devices is a number of cycles of the alternating current signals produced by the first electrical grid, and the number of occurrences associated with the second monitoring devices is a number of cycles of the alternating current signals produced by the second electrical grid.

18. The machine readable medium of claim 14, wherein the first and second electrical grids both supply alternating current signals to a data center.