According to one embodiment, an electrical contact assembly is disclosed. The assembly includes a layer of a conducting metal, a layer of copper adjacent to the layer of conducting metal, and a face layer comprising silver graphite adjacent to the layer of copper.

A high voltage gas switch includes a gas-tight housing containing an ionizable gas at a preselected gas pressure. The gas switch includes a gas-tight housing containing an ionizable gas at a gas pressure selected based upon a Paschen curve for the ionizable gas, where the Paschen curve plots breakdown voltages of the ionizable gas as a function of gas pressure multiplied by grid-to-anode distance, and where values of gas pressure multiplied by grid-to-anode distance increase over at least a portion of the Paschen curve in conjunction with increasing breakdown voltages. The gas switch also includes an anode disposed within the gas-tight housing, a cathode disposed within the gas-tight housing, and a control grid positioned between the anode and the cathode, where the control grid is spaced apart from the anode by a grid-to-anode distance selected based upon a desired operating voltage.

An electrical connection for medium and high voltage switchgears includes an electrical terminal of a switchgear. An electrical contacting surface of the electrical terminal as first current carrying part is electrically connected with a contacting surface of an external electrical connector part as second current carrying part via a connecting system. The connecting system includes a stretch-bolt function, which is integrated in one of the current carrying parts. The stretch bolt function is provided with a male screw thread at the extending end, which is configured to be screwed into a female threaded hole of the second current carrying part.

An electric contact system includes a moving member movable in a vertical direction, a movable contact mounted on and moved with the moving member, a static contact, and an arc extinguishing device including a movable bracket movable in a horizontal direction and an arc extinguishing sheet mounted on and movable with the movable bracket. The movable contact moves between a switch-on position and a switch-off position. The movable bracket is moved by the moving member between a first position and a second position when the movable contact is moved. When the movable bracket is moved to the first position, the arc extinguishing sheet is moved beyond a contact area between the movable contact and the static contact and allows the movable contact to electrically contact the static contact. When the movable bracket is moved to the second position, the arc extinguishing sheet is moved into the contact area between the movable contact and the static contact to electrically isolate the movable contact from the static contact.

A HVDC disconnector is disclosed. The HVDC disconnector comprises a fixed contact comprising a guide and a pair of conducting members positioned in the guide wherein the first and second conducting members are both tulip contacts; a movable contact comprising a fixed arm and a mobile arm having a conducting terminal, wherein the mobile arm is movable from an open position to a closed position to close a connection between the fixed contact and the second contact.

A contact assembly for connecting electrically and mechanically a first terminal of a first apparatus to a second terminal of a second apparatus, wherein at least one of the first and the second apparatus is movable with respect to the other along a connection/disconnection direction, includes: a plurality of electrically conducting contact-finger-elements, each including a main contact portion configured for engaging the second terminal and an auxiliary contact portion for engaging the first terminal, wherein the finger-contact-elements are supported by a support frame of the contact assembly connectable to the first terminal or are configured for being directly connectable and supportable by the first terminal; one or more spring elements configured for acting on the contact-finger-elements so to urge the main contact portions against the second terminal when the first and the second apparatus are connected. The main contact portions of at least two of the plurality of contact-finger-elements are shifted one relative to the other in such a manner so to engage the second terminal in subsequent moments when the first apparatus is being connected to the second apparatus by a relative movement thereof along the connection/disconnection direction.

An embodiment of the invention relates to a contact pin for an electric switch. The contact pin is designed as a composite support.

An alternative gas current pause circuit interrupter with an internally switched resistor-varistor impedance. The varistor limits the voltage rise across the main contactor limiting restrikes, while the resistor limits the current through the interrupter. The values of the resistor and varistor are selected to creates a current pause in the current. In a representative embodiment, the current pause performance is less than 10% of the rated line current for at least 15% of the half-cycle period allowing a plain break butt impedance contactor to be utilized without excessive arcing. For another embodiment the current pause performance is less than 5% of the rated line current for at least 20% of the half-cycle period. SF6 free alternative gas current pause circuit interrupters using a 60% CO2 blend can achieve similar or improved transient voltage performance compared to similarly sized conventional SF6 gas interrupters operating at the same voltage rating.

A high voltage gas switch includes a gas-tight housing containing an ionizable gas at a preselected gas pressure. The gas switch includes a gas-tight housing containing an ionizable gas at a gas pressure selected based upon a Paschen curve for the ionizable gas, where the Paschen curve plots breakdown voltages of the ionizable gas as a function of gas pressure multiplied by grid-to-anode distance, and where values of gas pressure multiplied by grid-to-anode distance increase over at least a portion of the Paschen curve in conjunction with increasing breakdown voltages. The gas switch also includes an anode disposed within the gas-tight housing, a cathode disposed within the gas-tight housing, and a control grid positioned between the anode and the cathode, where the control grid is spaced apart from the anode by a grid-to-anode distance selected based upon a desired operating voltage.

Switchgear comprises a support structure that supports one or more bus conductors. The bus conductor(s) each extend longitudinally in a bus direction. The switchgear further includes one or more circuit breaker bays. Each circuit breaker bay comprises feeder cable terminal(s) configured to respectively terminate feeder cable(s). Each circuit breaker bay further comprises a circuit breaker that is spaced from the feeder cable terminal(s) in the bus direction, and that comprises terminal pair(s). Each pair includes a bus-side terminal via which the circuit breaker connects to a respective bus conductor and a feeder-side terminal via which the circuit breaker connects to a respective feeder cable terminal. The circuit breaker is also configured to selectively interrupt current between the bus-side terminal and the feeder-side terminal of each terminal pair. The bus-side terminal and the feeder-side terminal of each terminal pair are spaced from one another in the bus direction.