US 4,250,365 AGranted

Current interrupter for fault current limiter and method

AssigneeElectric Power Research Institute, Inc.

InventorLorne D. McConnell

Life of this patent

Estimating the term…

Loading patent…

Abstract

A current interrupter is provided for use in controlling currents associated with power line faults. The interrupter is of the type having a housing filled with a dielectric fluid such as pressurized sulfur hexafluoride liquid and having electrodes extending through the walls of the housing. Associated with the electrodes is a movable contact member which when closed provides a path for current flow and which is movable to break a circuit. The housing includes a fluid chamber having a passage for fluid communication with the remaining interior of the housing. The movable contact member closes the passage when in its closed position. The method of the invention includes rapidly increasing the pressure in the chamber to move the contact from its closed position. A chemical propellant drives a piston against the fluid in the chamber. The fluid drives the movable contact member to open the passage and to break the current path, causing an arc. The fluid escaping from the chamber flows transverse to the arc thereby increasing the voltage drop of the interrupter.

Claims9

Dependent claims

A current interrupter for use in controlling current associated with power line faults comprising:

a housing, a pair of electrode members fixed in spaced relation in said housing, a contact member supported in said housing for movement between closed and open positions, said contact member being electrically interconnected with one of said pair of electrode members at all times and being in electrical contact with the other of said pair of electrode members when in said closed position and spaced from said other of said pair of electrode members when in said open position, a third electrode member fixed in said housing and spaced from both said pair of electrode members, said contact member being spaced from said third electrode member when in said closed position and being in electrical contact with said third electrode member to interconnect said third electrode member with said one of said pair of electrode members when in said open position, a chamber in the interior of said housing for holding a dielectric fluid, a passage between said chamber and the interior of said housing, said contact member blocking and closing said passage when in said closed position, and means in said housing for rapidly incresing fluid pressure in said chamber to force escape of said dielectric fluid through said passage and thereby move said contact member from said closed position to said open position by means of fluid pressure.

Dependencies are inferred from the claim text.