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.

According to one embodiment, an excitation inrush current suppressing apparatus comprising: bus voltage measurement equipment which measures each phase voltage of the single-phase AC-side bus; transformer voltage measurement equipment which measures a single-phase-side voltage of the transformer; phase detector which detects a cutoff phase when opening the circuit breaker by monitoring each phase voltage measured by the bus voltage measurement equipment and the single-phase-side voltage measured by the transformer voltage measurement equipment, holds the detected cutoff phase, and outputs the same phase as the held cutoff phase; and close command output device which closes the circuit breaker by the same voltage phase as the cutoff phase output from the phase detector.

An electric power distribution switchgear is connected between an electric power grid and an electric power equipment. The switchgear includes a synchronized vacuum switching apparatus configured to break the current to the electric power equipment using a synchronized technique to avoid re-ignition during the breaking and thus any transients caused by such re-ignition; and a surge arrester arrangement connected to the electric power equipment, the surge arrester arrangement being designed and configured to only handle transients caused by the current chopping at the breaking. The surge arrester arrangement can be arranged remote from the electric power equipment, such as e.g. in the same casing as the synchronized vacuum switching apparatus.

An apparatus for predicting an operating time in a power device includes an operating characteristic parameter estimating unit, and only the operation historical data in the vicinity of a current operation environmental condition is extracted and input by a vicinity operation historical data extracting unit.

A method for controlling a power switching apparatus to solve problems including: setting a target time reaching a predetermined position immediately before a target phase by a time calculator during an opening and closing operation of a movable arc contact with respect to a fixed arc contact in a target phase at a predetermined average switching speed; and controlling an electric motor at a speed equal to or less than an average switching speed immediately before the target phase from an operation start time to the target time by a motor controller.

A circuit breaking apparatus comprises a circuit breaker, a motor drive system, and a controller. The circuit breaker is electrically connectable to a power line. The motor drive system is mechanically coupled to the circuit breaker and configured to operate the circuit breaker such as to perform a movement including at least an opening movement from a closed position to an open position, thereby electrically interrupting the power line. The controller includes a model of at least one of the motor drive system and the circuit breaker. The controller is configured to receive reference travel curve information of the movement; generate actuator information from the reference travel curve information based on the model; and output the actuator information.

A method and an apparatus for controlling a circuit breaker in an electrical energy supply network. A switching signal is generated by a protective or control device of the energy supply network and the switching signal is transmitted to a control unit of the circuit breaker. The control unit is caused to open the switching contacts of the circuit breaker upon reception of the switching signal. In order to ensure a switching operation which is as fast as possible even in those energy supply networks in which phases of the current to be switched by a circuit breaker which are free of zero crossings can occur, a current flowing through the circuit breaker is recorded and is checked for the occurrence of zero crossings. The transmission of the signal for opening the switching contacts is prevented until at least one zero crossing has been detected.

A power switching control device includes a voltage measurement unit to measure a power-source-side voltage of a circuit breaker and a load-side voltage of the circuit breaker, an inter-pole-voltage estimation unit to estimate a future inter-pole voltage from a value of the power-source-side voltage and a value of the load-side voltage, a target closing-clock-time determination unit to set a target activation point of the circuit breaker on a waveform of an absolute value of the future inter-pole voltage, set an inter-pole withstand-voltage characteristic line calculated from a rate of decrease of dielectric strength, so that the inter-pole withstand-voltage characteristic line passes through the target activation point, and determine a clock time when the inter-pole withstand-voltage characteristic line becomes zero as a target closing clock time of the circuit breaker, and a closing control unit to close the circuit breaker at the target closing clock time.

A contactor apparatus and method for operating the contactor apparatus can include a contactor assembly with a contactor coil operably coupled to a contactor switch. One or more sensors can be provided in the contactor assembly adapted to measure one or more aspects of the contactor assembly. Based upon the measured aspects, a controller can initiate operation of the contactor switch to effectively toggle the contactor switch at a zero-crossing point along an alternating current waveform.

The present disclosure provides a contact actuating unit for an electrical circuit breaker. The contact actuating unit includes an electro-mechanical device. An actuator of the electro-mechanical device is connected to a contact arrangement in the electrical circuit breaker. The contact actuating unit further comprises a control unit. The control unit is configured to control the electro-mechanical device to move the actuator and to bring the contact arrangement from a first to a second position. The contact actuating unit further includes a command feed forward or motion trajectory and feed forward controller, configured to provide one or more data signals. At least one of the provided data signals is indicative of a predetermined force and/or torque value, adapted to command the control unit to move the contact arrangement with the actuator to a predetermined position.