A switch controls current to be supplied to an inductive load when turned on. A clamp circuit clamps a flyback voltage resulting from turning off the switch. The clamp circuit has a first clamping voltage responsive to the switch being turned off, and has a second clamping voltage, higher than the first clamping voltage, responsive to a current level through the inductive load being lower than a predetermined current level. That ensures that as the current comes down to levels required to break contact, the clamp voltage is increased to speed the collapse of the magnetic field when needed to minimize contact wear by maintaining armature momentum.

A generator has a voltage regulator that includes a first control unit for lowering an output voltage of the generator when a first maximum value is exceeded and a second control unit for lowering the output voltage either when a first maximum value is exceeded or when a second maximum value that is different from the first maximum value is exceeded.

A solenoid coil discharging circuit includes a rectifier, transistor, and diode. The rectifier is coupled to an alternating current signal, and provides a rectified signal in response to being coupled to the alternating current signal. The transistor is coupled to the rectifier circuit, and biased in on in response to the alternating current signal being coupled to the rectifier, thereby enabling coupling of the rectified signal to a solenoid coil. The diode is coupled to the rectifier, and discharges current from the solenoid coil in response to the alternating current signal being de-coupled from the rectifier. A method of discharging a solenoid coil includes rectifying an alternating current signal to provide a rectified signal, biasing a transistor on in response to the alternating current signal being rectified, thereby enabling coupling of the rectified signal to the solenoid coil through the transistor, and discharging current from the solenoid coil through the diode in response to discontinuing rectification of the alternating current signal.

A converter for avoiding a short-circuit fault of the converter while inhibiting a surge impact includes: a power factor correction (PFC) circuit, a surge protection circuit, and a switch circuit. The PFC circuit is configured to: convert a first component of a first alternating current received by an alternating current terminal of the PFC circuit into a first direct current, and output the first direct current through a direct current terminal of the PFC circuit; and convert a second direct current received by the direct current terminal of the PFC circuit into a second alternating current, and output the second alternating current through the alternating current terminal of the PFC circuit.

The present application discloses a contactor coil control circuit, including a switch control circuit, a drive circuit, a fast turn-off circuit, a diode D1, a first MOS (Metal Oxide Semiconductor) transistor TR1 and a contactor coil. The fast turn-off circuit at least includes an MOS transistor TR2 or a triode; the cathode of the diode is connected to an input voltage VIN; the anode of the diode is connected to a first port of the fast turn-off circuit; a second port of the fast turn-off circuit is connected to the drain of the first MOS transistor; the source of the first MOS transistor is grounded; one end of the contactor coil L1 is connected to an input voltage, and the other end of the contactor coil is connected to the drain of the first MOS transistor; a third port of the fast turn-off circuit is connected to an output port of the drive circuit; an input port of the drive circuit is connected to a first output port of the switch control circuit; and a second output port of the switch control circuit is connected to the gate of the first MOS transistor. On the premise of turning off the contactor quickly, the coil control circuit is lower in loss, adopts a fewer of devices, and is lower in cost and smaller in volume.

A fast shut-off solenoid circuit network includes a solenoid circuit and a current dissipation circuit. The solenoid circuit is operable in response to an electrical current, and configured to operate in an enable mode and a disable mode. The current dissipation circuit is configured to dissipate the current discharged from the solenoid circuit in response to invoking the disable mode. The fast shut-off solenoid circuit network further includes a dissipation bypass circuit. The dissipation bypass circuit is configured to divert the current discharged by the solenoid circuit away from current dissipation circuit when operating in the enable mode.

A switch controls current to be supplied to an inductive load when turned on. A clamp circuit clamps a flyback voltage resulting from turning off the switch. The clamp circuit has a first clamping voltage responsive to the switch being turned off, and has a second clamping voltage, higher than the first clamping voltage, responsive to a current level through the inductive load being lower than a predetermined current level. That ensures that as the current comes down to levels required to break contact, the clamp voltage is increased to speed the collapse of the magnetic field when needed to minimize contact wear by maintaining armature momentum.

A solenoid coil discharging circuit includes a rectifier, transistor, and diode. The rectifier is coupled to an alternating current signal, and provides a rectified signal in response to being coupled to the alternating current signal. The transistor is coupled to the rectifier circuit, and biased in on in response to the alternating current signal being coupled to the rectifier, thereby enabling coupling of the rectified signal to a solenoid coil. The diode is coupled to the rectifier, and discharges current from the solenoid coil in response to the alternating current signal being de-coupled from the rectifier. A method of discharging a solenoid coil includes rectifying an alternating current signal to provide a rectified signal, biasing a transistor on in response to the alternating current signal being rectified, thereby enabling coupling of the rectified signal to the solenoid coil through the transistor, and discharging current from the solenoid coil through the diode in response to discontinuing rectification of the alternating current signal.

The disclosure relates to a contactor, which includes a coil unit including a coil and a first switch; a first power supply unit including a second switch and a voltage stabilizing diode, wherein the second switch is connected in parallel with the voltage stabilizing diode, and the first power supply unit is connected in series with the coil unit; a current detection unit, which is configured to detect a current flowing through the coil; a voltage detection unit, which is configured to detect a first supply voltage at the output; and the control unit, which is configured to control the switching on and off of the first switch according to the current detection signal, and to control the switching on and off of the second switch according to the voltage detection signal, wherein the first supply voltage is less than an input voltage.