Contactor arrangement for use in dielectric liquid
A contactor arrangement for operation in a dielectric liquid environment may include a first connection terminal and a second connection terminal, a contactor having a fixed contact, and a movable contact that is movable relative to the fixed contact, the contactor having an open state in which the movable contact is spaced apart from the fixed contact and a closed state in which the movable contact is in contact with the fixed contact so as to provide an electric connection through the contactor via the movable contact. The contactor arrangement may further include a conductor section.
1. A contactor arrangement for operation in a dielectric liquid environment, the contactor arrangement comprising:
a first connection terminal,
a second connection terminal,
a contactor having a fixed contact and a movable contact movable relative to the fixed contact along a movement axis, the contactor configured to switch between:
an open state in which the movable contact is spaced apart from the fixed contact and
a closed state in which the movable contact is in contact with the fixed contact so as to provide an electric connection through the contactor via the movable contact,
a conductor section connected in series with the contactor between the first connection terminal and the second connection terminal, wherein the conductor section and the fixed contact are arranged on opposite sides of the movable contact, the conductor section extending along the movable contact in the direction of current flow through the movable contact, the arrangement being such that a current between the first and second connection terminals via the movable contact and the conductor section results in an electromagnetic force being exerted on the movable contact,
wherein the conductor section and contactor are arranged such that in the open state of the contactor, the movable contact is spaced apart from the conductor section by a gap having a width along the movement axis of the movable contact that is less than 50% of a thickness of the movable contact along the movement axis, and
at least one isolation element arranged in the gap between the movable contact and the conductor section.
2. The contactor arrangement according to claim 1 , wherein the conductor section is connected and arranged such that in operation in the closed state, the current through the conductor section has a direction that is substantially opposite to the direction of the current through the movable contact, such that a repelling force is generated between the movable contact and the conductor section, wherein the repelling force increases the contact pressure between the movable contact and the fixed contact.
3. The contactor arrangement according to claim 1 , wherein the conductor section is connected and arranged such that in operation in the closed state, the current through the conductor section has a direction that is substantially parallel to the direction of the current through the movable contact, such that an attractive force is generated between the movable contact and the conductor section, wherein the attractive force acts on the movable contact to move the movable contact towards the open state.
4. The contactor arrangement according to claim 1 , wherein the fixed contact comprises a first fixed contact and a second fixed contact, each having a contact portion for contacting a respective contact portion on the movable contact in the closed state, the first fixed contact being connected to the first connection terminal, and the second fixed contact being connected to the conductor section.
5. The contactor arrangement according to claim 1 , wherein the movable contact comprises at least one contact plate extending in the direction of current flow through the movable contact, the contact plate having contact portions at each end thereof, and the contact portions facing respective contact portions on the fixed contact.
6. The contactor arrangement according to claim 1 , wherein the conductor section is a metal bar or a metal plate.
7. The contactor arrangement according to claim 1 , wherein one end of the conductor section is electrically connected to the second connection terminal or forms the second connections terminal, and wherein the other end of the conductor section is connected to the fixed contact of the contactor, said connection being provided by a U-shaped or C-shaped conductor section.
8. The contactor arrangement according to claim 1 , wherein the conductor section is a bus bar section.
9. The contactor arrangement according to claim 1 , further comprising one or more fixing elements configured to fix the position of the conductor section relative to the fixed contact.
10. The contactor arrangement according to claim 9 , wherein the fixing elements comprise isolating spacer elements and bolts affixed to the isolating spacer elements, the fixing elements being arranged between the conductor section and the fixed contact and being mechanically mounted thereto by the bolts.
11. The contactor arrangement according to claim 1 , wherein the first connection terminal and the second connection terminal of the contactor arrangement are connected to an input conductor or to a bus bar of a subsea device.
12. The contactor arrangement according to claim 1 , wherein in the open state of the contactor, the spacing between the movable contact and the conductor section is smaller than the thickness of the movable contact.
13. The contactor arrangement according to claim 1 , further comprising a subsea enclosure filled with a dielectric liquid, wherein the contactor arrangement is located in the subsea enclosure in the dielectric liquid.
14. A subsea electric device comprising:
a contactor arrangement comprising:
a first connection terminal,
a second connection terminal,
a contactor having a fixed contact and a movable contact movable relative to the fixed contact along a movement axis, the contactor configured to switch between:
an open state in which the movable contact is spaced apart from the fixed contact and
a closed state in which the movable contact is in contact with the fixed contact so as to provide an electric connection through the contactor via the movable contact,
a conductor section connected in series with the contactor between the first connection terminal and the second connection terminal, wherein the conductor section and the fixed contact are arranged on opposite sides of the movable contact, the conductor section extending along the movable contact in the direction of current flow through the movable contact, the arrangement being such that a current between the first and second connection terminals via the movable contact and the conductor section results in an electromagnetic force being exerted on the movable contact,
wherein the conductor section and contactor are arranged such that in the open state of the contactor, the movable contact is spaced apart from the conductor section by a gap having a width along the movement axis of the movable contact that is less than 50% of a thickness of the movable contact along the movement axis, and
at least one isolation element arranged in the gap between the movable contact and the conductor section.
15. The subsea electric device according to claim 14 , wherein the subsea electric device has an input conductor connected to a power source, wherein the contactor arrangement is connected to the input conductor to enable the disconnection of the subsea electric device from the power source.
16. The subsea electric device according to claim 14 , wherein the conductor section is connected and arranged such that in operation in the closed state, the current through the conductor section has a direction that is substantially opposite to the direction of the current through the movable contact, such that a repelling force is generated between the movable contact and the conductor section, wherein the repelling force increases the contact pressure between the movable contact and the fixed contact.
17. The subsea electric device according to claim 14 , wherein the conductor section is connected and arranged such that in operation in the closed state, the current through the conductor section has a direction that is substantially parallel to the direction of the current through the movable contact, such that an attractive force is generated between the movable contact and the conductor section, wherein the attractive force acts on the movable contact to move the movable contact towards the open state.
18. The subsea electric device according to claim 14 , wherein the fixed contact comprises a first fixed contact and a second fixed contact, each having a contact portion for contacting a respective contact portion on the movable contact in the closed state, the first fixed contact being connected to the first connection terminal, and the second fixed contact being connected to the conductor section.
19. The subsea electric device according to claim 14 , wherein the movable contact comprises at least one contact plate extending in the direction of current flow through the movable contact, the contact plate having contact portions at each end thereof, and the contact portions facing respective contact portions on the fixed contact.
20. The subsea electric device according to claim 14 , wherein the conductor section is a metal bar or a metal plate.