LOAD RESTORATION FOR FEEDER AUTOMATION IN ELECTRIC POWER DISTRIBUTION SYSTEMS

• US 20110029148A1
• Filed: 12/10/2008
• Published: 02/03/2011
• Est. Priority Date: 12/12/2007
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Research Ltd. (ABB Ltd.)
• Inventors: Stoupis, James, Donde, Vaibhav, Yang, Fang, Wang, Zhenyuan, Lubkeman, David
• Granted Patent: US 9,088,160 B2
• Time in Patent Office: Days
• US Class Current: 700/297
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: G06F 11/1441 Resetting or repowering
• CPC Class Codes: G06F 2201/805 Real-time
• CPC Class Codes: H02H 3/06 with automatic reconnection
• CPC Class Codes: H02H 3/265 responsive to phase angle between voltages or between currents
• CPC Class Codes: H02H 7/28 for meshed systems
• CPC Class Codes: Y04S 10/30 State monitoring, e.g. fault, temperature monitoring, insulator monitoring, corona discharge
• CPC Class Codes: Y04S 10/52 Outage or fault management, e.g. fault detection or location

Abstract

A method and system restores power in a power distribution network. The network includes a plurality of power sources, a plurality of loading zones, a plurality of switching devices interconnected between the plurality of power sources and the plurality of loading zones, and an intelligent electronic device associated with each of the plurality of switching devices to control the switching devices. A base network state is defined and a power restoration logic is created for the base network state. A simulation is run for the power restoration logic and then the power restoration logic is transmitted to a power restoration controller which thereafter monitors and controls the intelligent electronic devices.

Claims

1. A method of restoring power in a power distribution network having a plurality of power sources, a plurality of loading zones, a plurality of switching devices interconnected between the plurality of power sources and the plurality of loading zones, an intelligent electronic device associated with each of the plurality of switching devices to control the switching devices, the method comprising:

providing at least one power restoration controller in communication with the intelligent electronic devices;

defining at least one base network state;

creating power restoration logic for said at least one base network state;

simulating the power restoration logic for said at least one base network state; and

transmitting the power restoration logic to the at least one power restoration controller which thereafter monitors and controls the intelligent electronic devices.

2. The method according to claim 1 wherein said step of defining at least one base network state includes defining a plurality of base network states.

3. The method according to claim 2 wherein said step of creating power restoration logic for a plurality of base network states includes, for each base network state, automatically generating power restoration logic for a simulated single permanent fault at each of the load zones.

4. The method according to claim 3 further comprising isolating a permanently faulted load zone and implementing the restoration logic correlating to the permanent fault at the faulted load zone.

5. The method according to claim 1 wherein said step of defining at least one base network state includes defining loading capacity of the plurality of switches and the plurality of power sources and defining a network topology interrelating the plurality of switches and plurality of power sources.

6. The method according to claim 5 wherein the base network states are defined for a plurality of electric power usage patterns.

7. The method according to claim 6 wherein a first base network state is defined for summer electric power usage patterns and a second base network state is defined for winter electric power usage patterns.

8. The methods according to claim 5 further comprising the step of validating that the at least one base network state does not violate radial load requirements or capacity constraints.

9. The methods according to claim 1 wherein said step of creating power restoration logic for each base network state comprises automatically generating the restoration logic, displaying the restoration logic to a user, and allowing the restoration logic to be modified by the user.

10. The methods according to claim 1 wherein said step of creating power restoration logic for each base network state comprises:

creating a study network of un-served loads after fault isolation;

simulating the opening of all switches in the network;

moving downstream from each of the simulated power sources and closing one switch at a time;

computing the remaining available capacity, and if capacity is inadequate, marking the last opened switch as a tie-switch, otherwise, continuing until a tie-switch or multi-source load zone is reached;

using the simulated power source with the maximum remaining capacity for any multi-source supplied load reached by more than one power source; and

marking all switches connected to the multi-source load zone from power sources other than the power source having maximum capacity as tie-switches.

11. The method according to claim 1 wherein said step of simulating the predefined power restoration logics further comprises the step of simulating a fault at each loading zone.

12. The method according to claim 11 wherein the simulation is visually displayed to a user.

13. The method according to claim 1 further comprising generating and executing power restoration logic dynamically.

14. The method according to claim 13 wherein said step of generating and executing power restoration logics dynamically further comprises dynamically generating power restoration logic if a fault occurs when not in the power distribution network is not configured in the at least one base network state.

15. The method according to claim 14 wherein, when dynamically generating power restoration logic and more than one alternate source is available, choosing the source according to either predefined path user preferences or a capacity reservation factor.

16. The method according to claim 14 wherein, when dynamically generating power restoration logic and more than one alternate source is available, choosing the source with the largest priority value, wherein the priority value is calculated according to:

AltPriority(i)=AltPathPriority(i)*PF+AvailCapacityFactor(i)*(1−

PF);

where AvailCapacityFactor(i) is the post-restoration available capacity reservation factor of the corresponding alternative power restoration path i, and AltPathPriority(i) is a user defined priority setting of an alternative power restoration path (i), and PF is a user defined preference factor.

17. The method according to claim 16 wherein AvailCapacityFactor(i) is computed according to:

AvailCapacityFactor(i)=(Capacity−

TotalLoad)/Capacity

where Capacity is the source capacity of the alternative power restoration path i, and TotalLoad is the total load of the source after the restoration.

18. A method of restoring power in a power distribution network having a plurality of power sources, a plurality of loading zones, a plurality of switching devices interconnected between the plurality of power sources and the plurality of loading zones, an intelligent electronic device associated with each of the plurality of switching devices to control the switching devices, and a power restoration controller in communication with the intelligent electronic devices the method comprising:

isolating the loading zone that is in a faulted state;

identifying one or more un-served load networks including loading zones downstream from the loading zone in a faulted state;

restoring power to each un-served load network from a single power source;

opening the switch or switches that separate each un-served load network into two or more sub-networks if no single power source is capable of restoring power to the un-served load network; and

restoring power to each said sub-networks from a single power source, until the source capacity is exhausted or switch loading capacity is violated.

19. The method according to claim 18 wherein the step of opening the switch or switches that separate each un-served load network further comprises:

determining if more than one switch configuration is capable of separating the un-served load network to the two or more sub-networks;

selecting the switch configuration that best balances loads of the power sources restoring power to each sub-network.

20. The method according to claim 18 wherein the step of opening the switch or switches that separate each un-served load network further comprises:

determining if more than one switch configuration is capable of separating the un-served load network to the two or more sub-networks;

selecting the switch configuration based on user defined preferences.