The invention is intended to provide a circuit breaker or a circuit breaker operating method enabling a current interruption action to be performed efficiently. A circuit breaker is characterized in that includes a fixed contact and a movable contact that comes in and goes out of contact with the fixed contact; a main circuit conductor that is electrically connected to the fixed contact and the movable contact; an operating mechanism including a mover configured by concatenating permanent magnets or magnetic materials alternately having opposite N and S magnetic polarities along the direction of motion axis of the movable contact and magnetic poles disposed to face the N and S magnetic polarities of the mover and wound with windings; a current detector that detects a current flowing through the main circuit conductor; and a control device that varies the amount of a current to be supplied to the windings of the magnetic poles, depending on a current value detected by the current detector.

A system and methods providing for minimizing the arc energy delivered to the pads of a plurality of contactors using a single control coil based on monitoring the electrical sine waves of the three alternating current electrical poles and calculating the instant to energize or deenergize a single control coil. The remainder of the contactors will make or break based on an offset in time from the making or breaking of the control contactor.

A contactor includes a coil through which current flows in an active state of the contactor; a controller configured to control the contactor; and a voltage converter, wherein, in the active state, the voltage converter is configured to converts an input voltage into a coil voltage which drops across the coil. The voltage converter can be electrically switched back into the active state from an inactive state using the controller. The contactor is configured to be switched into the active state from the inactive state by activating the voltage converter. The contactor is switched out of the active state into the inactive state by deactivating the voltage converter.

A wireless power transmission system includes a power control device, a power transmitting device, a relay device, and a power receiving device. The power control device includes a direct-current power supply, and a main control circuit that generates a first load instruction value and a second load instruction value. The power transmitting device returns a first response signal and information on alternating-current power supplied to a load circuit in the relay device, such as a voltage value, when receiving the first load instruction value. The load circuit returns a second response signal when receiving the second load instruction value. The main control circuit determines that not the load circuit but the relay-side power receiving circuit is faulty when not receiving the second response signal within a first period and receiving the first response signal within a second period and not receiving is the information within a second period.

In some aspects, a relay control device includes a processor and a timer. The processor is electrically connectable to a relay that controls current flow to a load device. The processor causes the relay to be actuated at a first point in time so that a current flows to the load device. The processor determines an actuation duration for the relay from a measurement of the load current that is obtained with a current sense component. The processor determines a frequency of an input voltage or current from the measured load current. The processor synchronizes the timer with this frequency and identifies a zero-crossing point for a second load current based on the synchronized timer. The processor subsequently causes the relay to be actuated at a time that is offset from the zero-crossing point by the actuation duration.

A controller for an alternating current contactor includes: a filtering and rectification circuit that filters and rectifies external alternating current; an electromagnet component driven by an output of the filtering and rectification circuit that performs actions of attraction, holding or releasing; a power transistor circuit connected to the electromagnet component; and a microcontroller that controls the power transistor circuit to control the actions performed by the electromagnet component. The controller further includes a voltage control loop that provides a voltage feedback signal and a current control loop that provides a current feedback signal to the microcontroller. The microcontroller generates a control signal according to the voltage feedback signal. The control signal is a PWM control signal having different duty cycles during the attraction and holding of the electromagnet component so that the current does not exceed a predetermined current threshold during the attraction and bolding of the electromagnet component.

A three phase switching device and method for reducing arc energy and contact erosion during the opening and closing of electrical contacts, the device having one electromagnet and one armature. The device and method permits the closing of all three phases at calculated target points immediately prior to their current zero crossing by controlling the velocity at which the armature travels during the opening and closing process.

Methods, apparatus, and articles of manufacture to regulate relay coil switching are disclosed. A disclosed example method of regulating switching times of a relay having a pair of contacts to selectively and electrically couple an analog alternating current (AC) power source and a load includes forming a digital pulse train representative of an AC signal at the load, determining a first value corresponding to a representative pulse width of the digital pulse train, providing a first relay switching signal to the relay at a first time relative to a zero crossing of the AC signal, selecting a second time for providing a second relay switching signal to the relay based the first value and a second value representative of the width of a first pulse of the digital pulse train associated with the first relay switching signal at the first time, and providing the second relay switching signal to the relay at the second time.

A system and methods providing for minimizing the arc energy delivered to the pads of a plurality of contactors using a single control coil based on monitoring the electrical sine waves of the three alternating current electrical poles and calculating the instant to energize or deenergize a single control coil. The remainder of the contactors will make or break based on an offset in time from the making or breaking of the control contactor.

A DC solenoid coil current controller includes a rectifier, pulse width modulator, and power driver. The rectifier inputs an alternating current signal and a direct current signal, and outputs a rectified signal using at least one of the alternating current signal and the direct current signal. The pulse width modulator outputs a pulse width modulated signal in response to the rectified signal. The power driver controls a DC solenoid coil using the pulse width modulated signal, thereby enabling a direct current DC solenoid coil to be controlled in response to the alternating current signal. A method of controlling current to a DC solenoid coil is also disclosed.