Abstract: A DC circuit breaker capable of blocking a fault current flowing through a DC line when a fault occurs in the DC line is proposed. The DC circuit breaker includes a main switch connected to a first DC line at one end and connected to a second line at the other end; a first circuit unit connected in parallel to the main switch; and n second circuit units each connected in parallel to the main switch, wherein the first circuit unit is composed of a series connection of an inductor, a first capacitor and a first switch, the inductor or the first capacitor being connected to the first DC line and the first switch being connected to the second DC line.

Abstract: A configuration for generating a zero current pulse for generating a zero current crossing in an electrical component through which a direct current flows, in particular a vacuum interrupter, includes a switch and an electrical energy storage device or store having two poles through which the electrical energy storage device can be charged by a voltage source. A loop can be formed by the energy storage device, the electrical component through which the direct current flows and the switch, so that the energy storage device can be discharged by closing the switch while generating a zero current pulse counter to the direct current across the electrical component. The energy storage device has a plurality of energy storage elements for mutual generation of a zero current pulse.

Abstract: A DC voltage circuit breaker includes at least one interrupter and a commutator device connected in parallel with the interrupter. The commutator device includes a capacitor circuit. The capacitor circuit includes a parallel circuit having at least two capacitor branches and the capacitor branches each have a capacitor in series with a capacitor branch switch.

Abstract: The present invention relates to a method of extinguishing an electric arc, which occurs in low or high voltage switchgears, by pulse discharge. The electric arc is cut like a “fuse” by connecting a condenser (201) to both ends of the electric arc at the moment when it occurs and discharging the condenser (201) through the electric arc. The condenser is charged using a resistor (202) and a diode (203), and its discharge is adjusted by some auxiliary contacts.

Abstract: The present invention discloses an arc extinguishing switch, including a mechanical switch and a first electric branch connected in parallel with a first contact branch of the mechanical switch, the first electric branch includes a first controllable unidirectional turn-on subbranch and a second controllable unidirectional turn-on subbranch, the first controllable unidirectional turn-on subbranch and the second controllable unidirectional turn-on subbranch are respectively controlled by two thyristors to be turned on in AC positive and negative periods correspondingly and share a first capacitor connected in series with the two thyristors. The invention further discloses a switching method using the arc extinguishing switch. In the invention, the high power requirement for the thyristor in the arc extinguishing switch and the product cost are lowered, and it is avoided that the mechanical switch is bypassed when the short-circuit failure occurs on the thyristor.

Abstract: An electromechanical/solid-state AC relay has an electromechanical winding coil that moves an armature to force mechanical contacts to open or close. Electrical arcing across the mechanical contacts that occur as the contacts are opening or closing can damage and severely reduce the lifetime of the relay. Contact arcing is prevented by pulsing a triac on for a short period of time just before and after the mechanical contacts make or break contact. The triac limits the voltage difference across the mechanical contacts to less than one volt to prevent arcing. The triac is turned off after the mechanical contacts finish moving, reducing the heating and average power through the triac. A zero-sampling circuit that detects when the AC input voltage switches across 0 volts and activates a control integrated circuit to switch on the triac during zero-crossings to minimize power surges.

Abstract: A switching device for direct-current applications including a housing, and at least three current paths. Each current path includes a respective movable switching contact element, a respective stationary switching contact element, and a respective air break between the respective movable and stationary contact elements. Each movable switching contact element is movable into a closed position and into an open position. The switching device includes a quenching capacitor connected in parallel to the respective at least one air break of a first of the current paths and configured to at least one of prevent the formation of an arc and quench an arc formed therealong. The quenching capacitor is not coupled to a second of the current paths. The second current path is couplable in series to the first current path.

Abstract: A limiter device for a “dead tank” high voltage circuit breaker having a grounded metal tank, the circuit breaker having two terminals for connection respectively to a high voltage electricity line and to a link leading to a source that is situated upstream and that enables the line to be fed via the circuit breaker. It comprises a capacitor placed outside the tank of the circuit breaker and which is electrically connected between the two terminals of the circuit breaker to limit voltage recovery speeds both upstream and downstream of the circuit breaker, following an interruption due to a line fault.

Abstract: The gas-insulated line comprises a conductor (1A) disposed inside a case (3A) filled with a dielectric gas under pressure. A power capacitor (5) is electrically connected to the conductor while being disposed inside a compartment (3P) secured to the case (3A) and filled with a dielectric gas under pressure. The dielectric gas present in the compartment (3P) provides electrical insulation for the compartment relative to the power capacitor (5). In this way, electrical insulation of the gas-insulated line between the conductor (1A) and the case (3A) is maintained inside the compartment (3P) in which the power capacitor (5) and the conductor (1A) are electrically interconnected. This results in the gas-insulated line of the invention retaining small bulk and the ability to be used on the ground or buried.

Abstract: The invention concerns an open air high-voltage circuit breaker comprising a circuit breaker unit (13) and a control capacitor connected electrically in parallel to it and surrounded by a common composite isolation housing (7, 8) made essentially of plastic, resting a terminal column (1) fixed to one of its ends. The use of a composite isolation housing saves cost and weight at the upper end of the terminal column and also improves earthquake security.

Abstract: The steep initial rate of rise of the transient recovery voltage across the poles of a circuit breaker just after a fault current break is decreased. The breaking performance in the case of a short-circuit fault to ground taking place in an electrical power transmission system at relatively as near a place as several kilometers apart from the circuit breaker, that is a short-line-fault is improved by a saturable reactor having a capacitor connected in parallel therewith to the circuit breaker in series. As a result, as the saturable reactor changes from the magnetically saturated state to the unsaturated state just before the zero point of the fault current, the self-inductance of the saturable reactor gradually increases and an LC resonance is produced between the self-inductance of the saturable reactor and the capacitor connected to the saturable reactor in parallel.

Abstract: An insulation gas filled circuit breaker in which a circuit breaking portion including two separably opposing contacts and a capacitor connected in parallel between the two contacts in the circuit breaking portion are disposed in a closed metal container filled with gas having an insulating property. A shield is provided at both the side of the capacitor facing the circuit breaking portion and the side of the capacitor facing the closed metal container for relaxing the electric field concentration near the capacitor. The top end of the shield is positioned so as to extend from the contacting face between the capacitor and an electrode pressing the capacitor toward the capacitor by a predetermined distance, whereby the dielectric strength of the capacitor connected in parallel with the circuit breaking portion is increased and a highly reliable and compact insulation gas filled circuit breaker of a high voltage and a large capacity use is provided.

Abstract: Breaking poles (1) and (2) are respectively secured to respective conductor bodies (4) and (5) and electrically connected thereto, and the conductor bodies (4) and (5) are fixedly secured and connected to each other by an interpole insulating support body (3). Interpole capacitors (7) are accommodated in the respective side walls of the interpole insulating support body (3). These parts for the breaking portion are accommodated within a grounded metal container (19) together with insulating gas and are secured to an operating box (18) via an insulating support body (17). The breaking poles (1) and (2) are designed to be transmitted an actuating force from the operating box (18) via an actuating insulation rod (not shown) and perform a breaking/making operation.