An object is to provide a DC power supply connector that can suppress occurrence of an arc discharge at DC power off with a small-scale configuration without reducing power efficiency during DC power supply and can reduce heat generation.

The connector includes, on at least any of a positive-electrode-side electrode side and a negative-electrode-side electrode side, a movable contact piece (20c) that touches a first contact (25) in a state where a terminal (11) on a power receiving side has been inserted and to touch a second contact (24) in a state where the terminal has not been inserted, and a current limiting circuit (30) including a switching element (T1). The current limiting circuit (30) does not flow a current to the switching element (T1) in the case where the movable contact piece (20c) is touching the first contact (25), and flows a current to the terminal (11) through the movable contact piece (20c) until the movable contact piece (20c) is linked to the second contact (24) after separation from the first contact (25), and gradually decreases the flowing current.

A medium voltage load break switch includes a main contact and a knife. The knife is rotatable about a pivot point to connect to and be in contact with the main contact and to rotate about the pivot point to disconnect from and be spaced from the main contact. The load break switch also comprises a vacuum interrupter that has a fixed contact and a moveable contact. A lever rotates about a rotation point and a shaft of the moveable contact is aligned along an axis of the vacuum interrupter, and the shaft of the moveable contact is linked to the lever.

A circuit interrupting device including a vacuum interrupter, a separable ceramic capacitor, and an insulating housing. The vacuum interrupter includes a vacuum bottle and first and second contacts disposed within the vacuum bottle. The second contact is movable relative to the first contact between a closed position and an open position. The separable ceramic capacitor is electrically connected in parallel with the vacuum interrupter provided over an outer surface of the vacuum bottle. The insulating housing encloses the separable ceramic capacitor and the vacuum interrupter.

An object is to provide a DC power supply connector that can suppress occurrence of an arc discharge at DC power off with a small-scale configuration without reducing power efficiency during DC power supply and can reduce heat generation. The connector includes, on at least any of a positive-electrode-side electrode side and a negative-electrode-side electrode side, a movable contact piece (20c) that touches a first contact (25) in a state where a terminal (11) on a power receiving side has been inserted and to touch a second contact (24) in a state where the terminal has not been inserted, and a current limiting circuit (30) including a switching element (T1). The current limiting circuit (30) does not flow a current to the switching element (T1) in the case where the movable contact piece (20c) is touching the first contact (25), and flows a current to the terminal (11) through the movable contact piece (20c) until the movable contact piece (20c) is linked to the second contact (24) after separation from the first contact (25), and gradually decreases the flowing current.

Disclosed is a DC circuit breaker capable of interrupting fault currents flowing in both forward and backward directions. The DC circuit breaker includes: a first mechanical switch for interrupting a current in a DC transmission line; a first diode connected in parallel with the first mechanical switch; a second mechanical switch, connected in series with the first mechanical switch, for interrupting a current in the DC transmission line; a second diode connected in parallel with the second mechanical switch; an LC circuit connected in parallel with the first and second mechanical switches and including a capacitor and a reactor connected in series to induce LC resonance; a first unidirectional switching device connected in parallel with the LC circuit and switching a current to induce LC resonance; and a bidirectional switching device connected in series with the LC circuit and switching currents flowing in both forward and backward directions.

A switching system for switching an electrical device that includes a vacuum breaker. The vacuum breaker includes a fixed electrode, and a mobile electrode, able to move between a first position, referred to as a closed position, and a second position, referred to as an open position. The electrical device also includes a driving plate connected to the mobile electrode, and a main switch able to move between a first position allowing electrical current to pass in a main electric circuit of the electrical device and a second position preventing electrical current from passing in the main electric circuit, the main switch being configured to drive the driving plate during the transition from the first position to the second position, so as to cause the mobile electrode to make the transition from the closed position to the open position. The electrical device further includes a contact-maintaining element configured to maintain mechanical and electrical contact between the driving plate and the main switch while the driving plate is being driven by the main switch.

A vacuum interrupter for a high voltage air break switch is disclosed. The interrupter has a plurality of load interrupter contacts enclosed in axially aligned vacuum bottles, each bottle containing a fixed contact and a second contact movable axially away from the fixed contact to open position and toward the fixed contact to closed position. The bottles are positioned in an tubular housing of dielectric material having a top end member and a bottom end member. The vacuum bottles are mechanically coupled to one another in a stack with the top bottle supported by the top end member. At least one air permeable hydrophobic vent member is operatively disposed in the top end member and/or bottom end member and/or tubular housing to prevent condensation in the housing. The stack of vacuum bottles are axially supported at the bottom by a cushion spring assembly keeping the bottles in compression to prevent tension loads on the braze joints of the bottles.

The invention relates to an electric arc-blast nozzle for a circuit breaker comprising a middle portion forming a throat defining internally an axial passage for interrupting an electric arc, and two end portions extending on either side of the middle portion and being designed to receive respective arcing contacts and that are movable axially relative to each other. The middle portion and the two end portions are made of a same dielectric material obtained from a composition consisting of a fluorocarbon polymer matrix and of at least one oxide, the oxide(s) being present in a proportion by weight lying in the range 11% to 50%, relative to the total weight of the composition. The invention also relates to a circuit breaker including such a nozzle.

A direct current circuit breaker used in a self-commutated direct current power transmission system includes a high-speed circuit breaker and a low-speed circuit breaker connected in series. The high-speed circuit breaker includes a high-speed circuit breaker interruption unit to interrupt a DC current flowing through a direct current line when a fault has occurred, and a current limiting element connected in parallel therewith. The low-speed circuit breaker includes a low-speed circuit breaker interruption unit to interrupt a DC current when a fault has occurred. A time required for the high-speed circuit breaker interruption unit to interrupt the DC current is shorter than a time required for the low-speed circuit breaker interruption unit. The low-speed circuit breaker interruption unit completes interruption of the DC current before a voltage applied to the current limiting element becomes lower than a minimum voltage allowable for the system.

The invention relates to an electric arc-blast nozzle for a circuit breaker comprising a middle portion forming a throat defining internally an axial passage for interrupting an electric arc, and two end portions extending on either side of the middle portion and being designed to receive respective arcing contacts and that are movable axially relative to each other.

The middle portion and the two end portions are made of a same dielectric material obtained from a composition consisting of a fluorocarbon polymer matrix and of at least one oxide, the oxide(s) being present in a proportion by weight lying in the range 11% to 50%, relative to the total weight of the composition.

The invention also relates to a circuit breaker including such a nozzle.