Superconducting fault current limiter system

Patent metadata

Field	Value
Publication number	US-9912148-B2
Application number	US-201313835434-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Mar 15, 2013
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

A current limiter system includes a superconducting fault current limiter (SCFCL) operative to conduct load current during a normal operation state in which the SCFCL is in a superconducting state. The current limiter system also includes a shunt reactor connected in an electrically parallel fashion to the SCFCL and configured to conduct less current than the SCFL in the normal operation state, and a protection switch connected in electrical series with the SCFCL and shunt reactor and configured to disconnect the SCFCL for a predetermined time from a load current path during a fault condition after fault current exceeds a threshold current value.

First claim

What is claimed is:

1. A current limiter system, comprising:
a superconducting fault current limiter (SCFCL) configured to conduct load current during a normal operation state in which the SCFCL is in a superconducting state;
a shunt reactor connected in an electrically parallel fashion to the SCFCL and configured to conduct less current than the SCFL in the normal operation state; and
a protection switch including a set of electromagnetic coils, the set of electromagnetic coils having a first coil connected in a series to the SCFCL and a second coil connected in series to the shunt reactor wherein the protection switch is configured to disconnect the SCFCL for a predetermined time from a load current path during a fault condition when fault current exceeds a threshold current value,
wherein the protection switch further comprises a central magnetic component configured to complete a first electrical path containing the SCFCL in a first position, the first coil and second coil being disposed around a same portion of the central magnetic component, and wherein the first coil is disposed around the second coil.

2. The current limiter system of claim 1 , wherein the SCFCL is configured to conduct about eighty percent or greater of load current and the shunt reactor is configured to conduct about twenty percent or less of load current during the normal operation state.

3. The current limiter system of claim 1 , wherein the SCFCL is configured to conduct less than twenty percent of fault current and the shunt reactor is configured to conduct greater than eighty percent of fault current during an initial fault interval when fault current exceeds the threshold current value and before the SCFCL is disconnected from the load current path.

4. The current limiter system of claim 1 , wherein the SCFCL is configured to conduct zero percent of load current and the shunt reactor is configured to conduct one hundred percent of load current during a recovery period after the SCFCL is disconnected from the load current and after the load current drops below the threshold current value.

5. The current limiter system of claim 1 , wherein the set of electromagnetic coils is configured to exert a force effective to move the central magnetic component from the first position to a second position in which the first electrical path forms an open circuit when the fault current exceeds the threshold current.

6. The current limiter system of claim 5 further comprising a spring connected to the central magnetic component and having a spring time constant configured to move the central magnetic component from the second position to the first position within a return period comprising one to twenty seconds after fault current drops below the current threshold subsequent to the fault condition.

7. The current limiter system of claim 6 , wherein the return period comprises one to six seconds.

8. The current limiter system of claim 5 , further comprising an air cylinder, spring and lock mechanism connected to the central magnetic component and having a recovery time delay constant configured to move the central magnetic component from the second position to the first position within a return period comprising one to twenty seconds after fault current drops below the threshold current subsequent to the fault condition.

9. The current limiter system of claim 8 , wherein the return period comprises one to six seconds.

10. The current limiter system of claim 5 , further comprising a lever arm connected to the central magnetic component and having an opening speed time configured to move the central magnetic component from the first position to the second position within an actuation time comprising four to one hundred milli seconds after fault condition is initiated.

11. The current limiter system of claim 5 , wherein the second coil is configured to transmit the load current when the central magnetic component is in the second position.

12. The current limiter system of claim 1 , further comprising a monitor system configured to receive power from current drawn through the first and/or second coil.

13. A superconducting fault current limiter (SCFCL) system arranged in an electrical circuit comprising:
a first electrical path containing an SCFCL configured to conduct load current during a normal operation state in which the SCFCL is in a superconducting state;
a second electrical path electrically parallel to the first electrical path and containing a shunt reactor configured to conduct less current than the SCFL in the normal operation state; and
a protection component comprising:
a set of electromagnetic coils, the set of electromagnetic coils having a first coil connected in series to the SCFCL, a second coil connected in series to the shunt reactor; and
a central magnetic component configured in a first position to complete the first electrical path, the first coil and second coil being disposed around a same portion of the central magnetic component, wherein the first coil is disposed around the second coil,
wherein the protection component is configured to create an open circuit along the first electrical path containing the SCFCL for a predetermined time during a fault condition when fault current exceeds a threshold current value, wherein no current is conducted through the SCFCL during the predetermined time.

14. The SCFCL system of claim 13 , wherein the set of electromagnetic coils is configured to exert a force effective to move the central magnetic component from the first position to a second position in which the first electrical path forms an open circuit when the fault current exceeds the threshold current.

15. The SCFCL system of claim 13 , wherein the first electrical path comprises the SCFCL, the first coil, and the central magnetic component.

16. The SCFCL system of claim 13 , wherein the SCFCL is configured to conduct approximately one hundred percent of load current and the shunt reactor is configured to conduct approximately zero percent of load current during the normal operation state when total load current is less than 2000 A.

17. The current limiter system of claim 13 , wherein the SCFCL is configured to conduct less than twenty percent of fault current and the shunt reactor is configured to conduct greater than eighty percent of fault current during an initial fault interval when load current exceeds 5 kA, and before the SCFCL is disconnected from the load current path.

18. A current limiter system, comprising:
a superconducting fault current limiter (SCFCL) configured to conduct load current during a normal operation state in which the SCFCL is in a superconducting state;
a shunt reactor connected in an electrically parallel fashion to the SCFCL and configured to conduct less current than the SCFL in the normal operation state; and
a protection switch including a set of electromagnetic coils, the set of electromagnetic coils having a first coil connected in a series to the SCFCL and a second coil connected in series to the shunt reactor wherein the protection switch is configured to disconnect the SCFCL for a predetermined time from a load current path during a fault condition when fault current exceeds a threshold current value,
wherein the protection switch further comprises a central magnetic component configured to complete a first electrical path containing the SCFCL in a first position, the first coil and second coil being disposed around a same portion of the central magnetic component; and
a spring connected to the central magnetic component and having

Assignees

• Varian Semiconductor Equipment Ass Inc

Inventors

• Tekletsadik Kasegn D
• Stanley Charles L

Classifications

• H02H9/023 Primary

  Current limitation using superconducting elements · CPC title

• H01L39/16

  Electricity · mapped topic

• Y02E40/69

  Cross-Sectional Technologies · mapped topic

• H10N60/30

  Devices switchable between superconducting and normal states · CPC title

• Y02E40/60

  Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment · CPC title