Method and system for multi-IED event zone identification in an electrical grid

• US 9,202,168 B2
• Filed: 01/25/2013
• Issued: 12/01/2015
• Est. Priority Date: 01/26/2012
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Research Ltd. (ABB Limited)
• Inventors: Saarinen, Kari, Mousavi, Mirrasoul
• Primary Examiner(s): Gaffin, Jeffrey A
• Assistant Examiner(s): Misir, Dave
• Application Number:
  US13/750,469
• Publication Number:
  US 20130198124A1
• Time in Patent Office: 1,040 Days
• Field of Search: 706/46, 702 58- 59
• US Class Current: 1/1
• CPC Class Codes: G06N 5/02 Knowledge representation; Symbolic representation
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: Y04S 10/50 Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications

Abstract

A method of identifying at least one event zone subject to an event in a substation environment of an electrical grid. Thereby, data from multiple intelligent electronic devices can be synthesized in real-time whereby an operator can be presented with a single conclusion describing the event attributes thereby helping the operator to determine the mitigation actions as needed. The method includes receiving first event related data from the intelligent electronic devices, and based on the first event related data, determining whether the at least one monitoring zone subject to the event is a primary monitoring zone of at least one of the intelligent electronic devices or a non-primary monitoring zone for all of the intelligent electronic devices using ensemble decision making and probabilistic methods. It is also presented a system for carrying out the method.

Claims

1. A method of identifying at least one event zone subject to an event in a busbar system comprising a plurality of feeders and a plurality of intelligent electronic devices monitoring at least some of the feeders, wherein the method comprises:

receiving first event related data from the intelligent electronic devices, and

determining whether the at least one event zone subject to the event is a primary monitoring zone of at least one of the intelligent electronic devices or a non-primary monitoring zone for all of the intelligent electronic devices, a primary monitoring zone of an intelligent electronic device being a monitoring zone which that intelligent electronic device is assigned to monitor, a non-primary monitoring zone being either an event zone having a power level which differs from the power level monitored by the intelligent electronic devices or an adjacent monitoring zone to all of the electronic intelligent devices,

wherein the determining comprises determining a conditional probability that the first event related data is a result of the event having occurred in an adjacent monitoring zone of all intelligent electronic devices, conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of one of the intelligent electronic devices, conditional probabilities that the first event related data is a result of the event having occurred in a primary monitoring zone of more than one intelligent electronic device, each determined conditional probability thereby being associated with at least one event zone,

determining whether the event occurred in at least one primary monitoring zone or in a non-primary monitoring zone based on the conditional probabilities, and

determining a respective weighted probability value for each of the determined conditional probabilities based on prior probabiliy that the event occurred in an adjacent monitoring zone for each intelligent electronic device, that the event occurred in a primary monitoring zone of one intelligent electronic device, that the event occurred in a primary monitoring zone for more than one intelligent electronic device, wherein the step of determining whether the event occurred in a primary monitoring zone or a non-primary monitoring zone is based on the highest value of the weighted probabilities, wherein each prior probability is seen as a weight and each weighted probability value is obtained by multiplying a respective prior probability with the corresponding determined conditional probability.

2. The method as claimed in claim 1, comprising, in case the event occurred in at least one primary monitoring zone, identifying the at least primary monitoring zone in which the event occurred based on an association of the at least one primary monitoring zone with a weighted probability value.

3. The method as claimed in claim 1, comprising, in case the event occurred in a non-primary monitoring zone and all feeders are monitored by an intelligent electronic device, determining that the event occurred in the upstream monitoring zone.

4. The method as claimed in claim 1, comprising receiving second event related data, and in case the event occurred in a non-primary monitoring zone and not all feeders are monitored by an intelligent electronic device, determining a conditional probability that the first event related data is a result of the event having occurred in an adjacent monitoring zone for all intelligent electronic devices and a conditional probability that the first event related data is a result of the event having occurred in the upstream monitoring zone based on the second event related data, and determining whether the event occurred in an adjacent monitoring zone or the upstream monitoring zone based on the conditional probabilities.

5. The method as claimed in claim 4, comprising determining a weighted probability value for each of the determined second event related data conditional probabilities based on prior probability that the event occurred in an adjacent monitoring zone for each intelligent electronic device and that the event occurred in the upstream monitoring zone, wherein the step of determining whether the event occurred in an adjacent monitoring zone or upstream of the busbar system is based on the highest value of the weighted probabilities.

6. The method as claimed in claim 1, wherein the steps of determining the conditional probabilities involves determining a respective joint density function.

7. The method as claimed in claim 1, wherein the step of determining the weighted conditional probabilities involves determining a respective discriminant function.

8. The method as claimed in claim 1, wherein the determining of the conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of more than one of the intelligent electronic devices comprises determining conditional probabilities for all primary monitoring zone combinations.

9. The method as claimed in claim 1, wherein the first event related data received from each intelligent electronic device comprises probabilities concerning the event being a primary monitoring zone event for that intelligent electronic device or an adjacent monitoring zone event for that intelligent electronic device.

10. The method as claimed in claim 1, wherein the system synthesizes data from multiple intelligent electronic devices and provides an operator with a single conclusion describing the event thereby helping the operator to determine mitigation actions.

11. A computer program product comprising computer-executable components run on a processing unit that includes a hardware processor which is included in a system and causing the system to perform a method of identifying at least one event zone subject to an event in a busbar system comprising a plurality of feeders and a plurality of intelligent electronic devices monitoring at least some of the feeders, wherein the method comprises:

receiving first event related data from the intelligent electronic devices, and

determining whether the at least one event zone subject to the event is a primary monitoring zone of at least one of the intelligent electronic devices or a non-primary monitoring zone for all of the intelligent electronic devices, a primary monitoring zone of an intelligent electronic device being a monitoring zone which that intelligent electronic device is assigned to monitor, a non-primary monitoring zone being either an event zone having a power level which differs from the power level monitored by the intelligent electronic devices or an adjacent monitoring zone to all of the electronic intelligent devices,

wherein the determining comprises determining a conditional probability that the first event related data is a result of the event having occurred in an adjacent monitoring zone of all intelligent electronic devices, conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of one of the intelligent electronic devices, conditional probabilities that the first event related data is a result of the event having occurred in a primary monitoring zone of more than one intelligent electronic device, each determined conditional probability thereby being associated with at least one event zone,

determining whether the event occurred in at least one primary monitoring zone or in a non-primary monitoring zone based on the conditional probabilities, and

determining a respective weighted probability value for each of the determined conditional probabilities based on prior probability that the event occurred in an adjacent monitoring zone for each intelligent electronic device, that the event occurred in a primaary monitoring zone of one intelligent electronic device, that the event occurred in a primary monitoring zone of more than one intelligent electronic device, wherein the step of determining whether the event occurred in a primary monitoring zone or a non-primary monitoring zone is base on the highest value of the weighted probabilities, wherein each prior probability is seen as a weight and each weighted probability value is obtained by multiplying a respective prior probability with the corresponding determined conditional probability.

12. A system for identifying at least one event zone subject to an event in a busbar system comprising a plurality of feeders and a plurality of intelligent electronic devices monitoring at least some of the feeders, wherein the system comprises:

an input unit having computer-executable components executing thereon and arranged to receive first event related data from the intelligent electronic devices, and

a processing unit that includes a hardware processor having computer-executable components executing thereon and arranged to determine whether the at least one event zone subject to the event is a primary monitoring zone of at least one of the intelligent electronic devices or a non-primary monitoring zone for all of the intelligent electronic devices, a primary monitoring zone of an intelligent electronic device being a monitoring zone which that intelligent electronic device is assigned to monitor, a non-primary monitoring zone being either an event zone having a power level which differs from the power level monitored by the intelligent electronic devices or an adjacent monitoring zone to all of the electronic intelligent devices,

wherein the processing unit is arranged to;

determine a conditional probability that the first event related data is a result of the event having occurred in an adjacent monitoring zone of all intelligent electronic devices, conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of one of the intelligent electronic devices, conditional probabilities that the first event related data is a result of the event having occurred in a primary monitoring zone of more than one intelligent electronic device, each determined conditional probability thereby being associated with at least one event zone,

based on the conditional probabilities, to determine whether the event occurred in at least one primary monitoring zone or in a non-primary monitoring zone, and

to determining a respective weighted probability value for each of the determined conditional probabilities based on prior probabiliy that the event occurred in an adjacent monitoring zone for each intelligent electronic device, that the event occurred in a primary monitoring zone of one intelligent electronic device, that the event occurred in a primary monitoring zone of more than one intelligent electronic device, wherein the processing unit is arranged to determine that the event occurred in at least one primary monitoring zone or a non-primary monitoring zone is base on the highest value of the weighted probabilities, wherein each prior probability is seen as a weight and each weighted probability value is obtained by multiplying a respective prior probability with the corresponding determined conditional probability.

13. A method of identifying at least one event zone subject to an event in a busbar system comprising a plurality of feeders and a plurality of intelligent electronic devices monitoring at least some of the feeders, wherein the method comprises:

receiving first event related data from the intelligent electronic devices, and

determining whether the at least one event zone subject to the event is a primary monitoring zone of at least one of the intelligent electronic devices or a non-primary monitoring zone for all of the intelligent electronic devices, a primary monitoring zone of an intelligent electronic device being a monitoring zone which that intelligent electronic device is assigned to monitor, a non-primary monitoring zone being either an event zone having a power level which differs from the power level monitored by the intelligent electronic devices or an adjacent monitoring zone to all of the electronic intelligent devices,

wherein the determining comprises determining a conditional probability that the first event related data is a result of he event having occurred in an adjacent monitoring zone of all intelligent electronic devices, conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of one of the intelligent electronic devices, conditional probabilities that the first event related data is a result of the event having occurred in a primary monitoring zone of more than one intelligent electronic device, each determined conditional probability thereby being associated with at least one event zone,

determining whether the event occurred in at least one primary monitoring zone or in a non-primary monitoring zone based on the conditional probabilities,

receiving second event related data, and in case the event occurred in a non-primary monitoring zone and not all feeders are monitored by an intelligent electronic device, determining a conditional probability that the first event related data is a result of the event having occurred in an adjacent monitoring zone for all intelligent electronic devices and a conditional probability that the first event related data is a result of the event having occurred in the upstream monitoring zone based on the second event related data, and determining whether the event occurred in an adjacent monitoring zone or the upstream monitoring zone based on the conditional probabilities, and

determining a weighted probability value for each of the determined second event related data conditional probabilities based on prior probability that the event occurred in an adjacent monitoring zone for each intelligent electronic device and that the event occurred in the upstream monitoring zone, wherein the step of determining whether the event occurred in an adjacent monitoring zone or upstream of the busbar system is based on the highest value of the weighted probabilities.

14. The method as claimed in claim 13, comprising determining a respective weighted probability value for each of the determined conditional probabilities based on prior probability that the event occurred in an adjacent monitoring zone for each intelligent electronic device, that the event occurred in a primary monitoring zone of one intelligent electronic device, that the event occurred in a primary monitoring zone for more than one intelligent electronic device, wherein the step of determining whether the event occurred in a primary monitoring zone or a non-primary monitoring zone is based on the highest value of the weighted probabilities.

15. The method as claimed in claim 13, comprising, in case the event occurred in at least one primary monitoring zone, identifying the at least primary monitoring zone in which the event occurred based on an association of the at least one primary monitoring zone with a weighted probability value.

16. The method as claimed in claim 13, comprising, in case the event occurred in a non-primary monitoring zone and all feeders are monitored by an intelligent electronic device, determining that the event occurred in the upstream monitoring zone.

17. The method as claimed in claim 13, wherein the steps of determining the conditional probabilities involves determining a respective joint density function.

18. The method as claimed in claim 13, wherein the step of determining the weighted conditional probabilities involves determining a respective discriminant function.

19. The method as claimed in claim 13, wherein the determining of the conditional probabilities for each intelligent electronic device that the first event related data is a result of the event having occurred in the primary monitoring zone of more than one of the intelligent electronic devices comprises determining conditional probabilities for all primary monitoring zone combinations.

20. The method as claimed in claim 13, wherein the first event related data received from each intelligent electronic device comprises probabilities concerning the event being a primary monitoring zone event for that intelligent electronic device or an adjacent monitoring zone event for that intelligent electronic device.