A DC circuit breaker includes a case, two fixed contacts, two movable contacts, a bypass plate electrically connecting the two movable contacts, a moving block to move the bypass plate, a moving block biasing member to bias the moving block in a direction away from the fixed contacts, a thermally responsive member, a latch, a shutter, and a shutter biasing member. The thermally responsive member deforms when an installation surface equals or exceeds a prescribed temperature. The latch restricts movement of the moving block by locking the moving block when the thermally responsive member is in a pre-deformation state. The latch cancels the restriction of the movement the thermally responsive member deforms. The shutter is insertable between the fixed contacts and the movable contacts. The shutter biasing member constantly biases the shutter in a direction to be inserted between the fixed contacts and the movable contacts.

A method may include receiving a command to move one or more armatures configured to move between a first position that electrically couples one or more first movable contacts to one or more second contacts and a second position that electrically uncouples the one or more first movable contacts from the one or more second contacts. The method may also include determining an operating frequency of the system, dynamically determining an open-before-zero target point associated with the operating frequency, and transmitting a command to the switching device to move the one or more armatures from the first position to the second position at the open-before-zero target point to normalize the arc energy over the operating frequency range.

A circuit interrupter includes a first set of contacts connected in series with a second set of contacts, with both sets of contacts configured to open and close simultaneously. First and second arc extinguishers are associated with the first and second sets of contacts, respectively. A moveable permanent magnet moves as the sets of contacts simultaneously open and close, the moveable magnet generating a moveable magnetic field, a first stationary permanent magnet associated with the first arc extinguisher, the first stationary magnet generating a first stationary magnetic field, where the first stationary magnetic field and the moveable magnetic field are additive, and a second stationary permanent magnet associated with the second arc extinguisher, the second stationary magnet generating a second stationary magnetic field, where the second stationary magnetic field and the moveable magnetic field are also additive.

An electrical contactor has an arc extinguishing component. The electrical contactor includes a first electrical contact and a second electrical contact that, when the contactor is open, define a gap therebetween. The arc extinguishing component includes a magnet adjacent a first side of the gap and an electrically non-conductive shutter adjacent an opposing second side of the gap. The electrically non-conductive shutter capable of reciprocating from a first position to a second position wherein the first position is outside of the gap and the second position is within the gap.

A switching element (100) that comprises a switching unit (30), a first and a second coil unit (10, 20) for closing and opening the switching unit (30), wherein the first coil unit (10) comprises a first coil (12) and wherein the second coil unit (20) comprises a second coil (22). According to the invention, the first coil unit (10) comprises a first controllable delay circuit (14) that is connected in series with the first coil (12). The invention further relates to a switching device (200) that comprises a switching element (100) according to the invention. The invention further relates to a first and a second method for the operation of the switching device (200) according to the invention.

A switching element (100) that comprises a switching unit (30), a first and a second coil unit (10, 20) for closing and opening the switching unit (30), wherein the first coil unit (10) comprises a first coil (12) and wherein the second coil unit (20) comprises a second coil (22). According to the invention, the first coil unit (10) comprises a first controllable delay circuit (14) that is connected in series with the first coil (12). The invention further relates to a switching device (200) that comprises a switching element (100) according to the invention. The invention further relates to a first and a second method for the operation of the switching device (200) according to the invention.

The present invention discloses a system for limiting a peak current of short-circuit current, which comprises a first a first high-frequency branch configured to provide a first high-frequency current to a first switch (1SKa) of a first phase branch of a three-phase AC when the first phase branch occurs a short-circuit, wherein the first high-frequency current is configured to cause a zero-crossing point of a short-circuit current to appear before a zero-crossing point of the three-phase AC; a second high-frequency branch configured to provide a second high-frequency current to a second switch (1SKc) of a second phase branch of the three-phase AC when the second phase branch occurs a short-circuit, wherein the second high-frequency current is configured to cause a zero-crossing point of a short-circuit current to appear before a zero-crossing point of the three-phase AC, a third phase branch of the three-phase AC connected in parallel with the first phase branch and the second phase branch and configured to always supply power. The present invention superimposes the high-frequency current on the original short-circuit current of the switch, thereby the total time from the arc generation to extinction at the zero-crossing point and then to the judgement by the control system is shorter than the time that the short-circuit current peak appears. Therefore, it can effectively lower the damage of the short-circuit current peak to the dynamic stability of the switch and lower the impact on system equipment.

The present disclosure provides a DC mechanical circuit breaker that can utilize two switches, one of which can generate zero-crossing with an alternate oscillatory circuit for the other one, which can be a conventional zero-crossing-based AC breaker and can be used in the main circuit. This is different from the conventional single-switch commute-and-absorb method currently used. The present disclosure shows that disclosed circuit breaker improves the fault current extinction and significantly reduces the voltage rate-of-change while creating the current zero-crossing faster compared to the available technology. Thus, disclosed circuit breaker is capable of interrupting high DC currents with minimal arc through a less expensive AC circuit breaker. Simulation and hardware results are provided to show the efficiency of the disclosed circuit breaker.

A system for limiting a peak current of short-circuit current comprises a first high-frequency branch configured to provide a first high-frequency current to a first switch (1SKa) of a first phase branch of a three-phase AC when the first phase branch occurs a short-circuit; a second high-frequency branch configured to provide a second high-frequency current to a second switch (1SKc) of a second phase branch of the three-phase AC when the second phase branch occurs a short-circuit; and a third phase branch of the three-phase AC connected in parallel with the first phase branch and the second phase branch and configured to always supply power.

A circuit and method are disclosed enabling a direct current (DC) power source to power a load circuit designed for alternating current (AC) input. The circuit is arranged to be connected between a DC power source and a load circuit in which the load circuit includes an electric load and a switch with a mechanical contact in series with the load. The circuit comprises a contact opening detector arranged to detect an opening event of the switch contact and a damping component arranged to be triggered in response to the contact opening detector detecting a contact opening event. The triggered damping component causes a momentary lowering of a load circuit input voltage, such that the momentary lowering of the load circuit input voltage prevents the sustaining of an electric arc across the opened switch contact.