A hybrid circuit breaker includes a primary trip/isolation relay component and a primary trip/isolation relay component driver coupled to the primary trip/isolation relay component and structured to interrupt current from flowing to the load in an event of fault; a sensing mechanism structured to sense at least current, voltage, and power flowing to the load; a metrology component coupled to the sensing mechanism and structured to monitor and measure at least the current, voltage and power; a controller structured to detect the event of fault based on data received from the sensing mechanism and the metrology component and communicate with a user device; and a hybrid secondary switching device coupled to the controller and the primary trip/isolation relay component, the hybrid secondary switch device including secondary contacts, a miniaturized electromechanical relay and a power electronics circuit connected in parallel with the miniaturized electromechanical relay.

A device for controlling a pre-charge current generated when electrically connecting a first terminal and a second terminal, according to one embodiment of the present invention, may comprise: a switch for controlling a magnitude of a current flowing between the first terminal and the second terminal; a first resistor for generating a base voltage of a first transistor in proportion to a magnitude of the pre-charge current flowing between the first terminal and the second terminal; the first transistor for limiting the magnitude of the pre-charge current when a voltage generated by the first resistor is equal to or greater than a predetermined threshold voltage; a photocoupler for receiving, in a state insulated from a first power source, an optical signal from the first power source and supplying power; a capacitor charged by the power supplied by the photocoupler; a second transistor for controlling the magnitude of the pre-charge current on the basis of a charging voltage of the capacitor; and a second resistor for controlling an operating time of the second transistor along with the capacitor.

An arc suppressing circuit configured to suppress arcing across a power contactor coupled to an alternating current (AC) power source having a predetermined number of phases, each contact of the power contactor corresponding to one of the predetermined number of phases includes a number of dual unidirectional arc suppressors equal to the predetermined number of phases of the AC power source. Each dual unidirectional arc suppressor includes a first phase-specific arc suppressor configured to suppress arcing across the associated contacts in a positive domain, a a second phase-specific arc suppressor configured to suppress arcing across the associated contacts in a negative domain, and a coil lock controller, configured to be coupled between a contact coil driver of the power contactor, configured to detect an output condition from the contact coil driver and inhibit operation of the first and second phase-specific arc suppressors over a predetermined time.

A low-voltage circuit breaker includes at least one current sensor for determining the magnitude of the electric current of a conductor of the low-voltage circuit breaker; and at least one electromechanical switching unit for connecting and disconnecting at least two electrical contact points. In a first switching position of the movable contact point, two contact points are connected and in a second switching position the contact points are not connected to one another. The circuit breaker further includes at least one electronic switching unit having a semiconductor switching element, electrically conductive in a first switching state and electrically blocking in a second switching state; an electronic tripping unit, connected to the current sensor, the electronic switching unit and the electromechanical switching unit. Further, when current and/or current/time-period limit values of the conductor are exceeded, first the electromechanical switching unit is opened and then the electronic switching unit is blocked.

A circuit breaker comprises a solid-state bidirectional switch, a switch control circuit, current and voltage sensors, and a processor. The solid-state bidirectional switch is connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-on state and a switched-off state. The switch control circuit control operation of the bidirectional switch. The current sensor is configured to sense a magnitude of current flowing in an electrical path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage on the electrical path and generate a voltage sense signal. The processor is configured to process the current and voltage sense signals to determine operational status information of the circuit breaker, a fault event, and power usage information of a load connected to the load output terminal.

A system including an arc flash sensor that detects an arc flash event and an arc flash mitigation device in communication with the sensor. The mitigation device includes a path of least resistance having a path input and a path output. The arc flash sensor is located downstream the output. The mitigation device includes an electro-mechanical switch between the input and the output and an actuator. The mitigation device also includes a bypass power switch device that includes a solid-state circuit interrupter and that conduct current between the input and the output in response to an open-circuit condition of the switch. A system controller is provided to generate a trigger to activate the actuator to generate the open-circuit condition of the switch, which causes the power switch device to interrupt a fault current associated with a fault event in response to detection of the arc flash event.

A device includes an electro-mechanical switching device having an open-circuit and closed-circuit conditions and a path of least resistance having a path input and a path output with the switching device between the input and the output. The device includes a bypass power switch device that comprises a solid-state circuit interrupter and that is configured to conduct current between the input and the output in response to an open-circuit condition of the switching device. The device includes a current sensor that is connected to the output and configured to detect a fault current event. The device includes an actuator that is coupled to the switching device and a controller that is configured to generate a trigger signal to activate the actuator to cause the open-circuit condition of the switching device and to interrupt the fault current event by the power switch device, based on the detected fault current event.

A high speed arc suppressor and method include a first phase-specific arc suppressor configured to suppress arcing across contacts of the power contactor in a positive domain and a second phase-specific arc suppressor configured to suppress arcing across the contacts in a negative domain. First and second high speed switches are configured to enable and disable operation of an associated one of the first and second phase-specific arc suppressors. First and second drivers are configured to drive the first and second high speed switches.

Solid state and hybrid circuit protection devices include improved chemical, static discharge and impact resistant housing construction, arc-free switching operation, secure terminal assemblies and thermal management features. The solid state and hybrid circuit protection devices are ignition protected and avoid possible explosions and therefore obviate a need for conventional explosion-proof enclosures to ensure safe operation of an electrical power system in a potentially explosive environment.

A switching apparatus for electric power distribution grids including: a withdrawable first switching unit having one or more first electric poles; a withdrawable second switching unit having one or more second electric poles and electrically connected ins series with said first switching unit; and a controller implementing control strategies directed to increase the safety of the withdrawal manoeuvres of said first and second switching units.