Within a direct current hybrid circuit breaker (DC HCB), a commutation unit (CU) is provided in a semiconductor switch path in series with a semiconductor switch to facilitate opening the DC HCB. The semiconductor switch path is connected in parallel with a mechanical switch path that includes a mechanical switch. The CU is a controlled voltage source which applies a reverse biased voltage on the semiconductor switch path. The CU causes the current through the mechanical switch to ramp down while the current through the semiconductor switch ramps up to a supply current. The CU maintains the current through the mechanical switch to remain at a zero vale by compensating for the voltage drop across the semiconductor switch and the self-inductance of the semiconductor switch path. The mechanical switch can open without current and against no recovery voltage.

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 control circuit for a switch device including a first switch element including a movable contact and a drive coil that controls the movable contact of the first switch element, the control circuit for returning the movable contact when the drive coil turns off the movable contact after the drive coil turns on the movable contact during supply of a source voltage from a power source, the control circuit includes a second switch element inserted between a rectifier circuit or a surge absorbing element and the first switch element, the second switch element being turned off when the supply of the source voltage is turned off. The rectifier circuit or the surge absorbing element is connected between the power source and the control circuit. The first switch element is turned off the movable contact is returned by turning off the second switch element to turn off the first switch element.

A circuit interrupter includes a solid-state switch and a mode control circuit. The solid-state switch is serially connected between a line input terminal and a load output terminal of the circuit interrupter. The mode control circuit is configured to implement a first control mode and a second control mode to control operation of the circuit interrupter. The first control mode is configured to generate a self-bias turn-on threshold voltage for the solid-state switch during power-up of the circuit interrupter, while maintaining the solid-state switch in a switched-off state until the self-bias turn-on threshold voltage is generated. The second control mode is configured to disrupt the self-bias turn-on threshold voltage and place the solid-state switch into a switched-off state.

An alternating current solid-state relay having a short-circuit protection function, comprises an output switch circuit, which is connected to a load loop in series and comprises two power switch transistors, a driver circuit having a short-circuit protection function, and a short-circuit detection circuit, wherein the two power switch transistors are IGBTs or MOS transistors and are in opposing series, and two terminals formed after series connection of the two power switch transistors serve as two output terminals of the alternating current solid-state relay; a power circuit supplies power to the driver circuit, and the driver circuit correspondingly controls on-off of the two power switch transistors according to a control signal accessed to an input terminal of the driver circuit, and detects through the short-circuit detection circuit whether or not a short circuit happens to a load; and if yes, the two power switch transistors are controlled to be turned off.

Provided is a switch apparatus that provides a connection or a disconnect between an input terminal and an output terminal, including a mechanical switch section and a first semiconductor switch section that are connected in series, between the input terminal and the output terminal; a second semiconductor switch section that is connected in parallel with the mechanical switch section and the first semiconductor switch section, between the input terminal and the output terminal; and a switch control section that individually controls respective ON/OFF timings of the first semiconductor switch section and the second semiconductor switch section and an open/close timing of the mechanical switch section.

A passive timing circuit for optocoupled relay has a rail having an output for an input terminal of the optocoupled relay. The circuit also has a capacitive network between the rail and ground. The capacitance of the capacitive network can be configured according to a timing period and the circuit does not require a voltage source other than that applied by the input terminal which, over the time period, increases voltage of the rail until the relay switches.

A semiconductor relay device includes a conversion circuit configured to receive an input signal from outside and pass a first current to a first node based on the input signal. A zener diode has an anode coupled to a second node and a cathode coupled to the first node. A resistor is coupled between the second node and a third node. A number n of diodes are serially coupled. A thyristor has an anode coupled to the first node, a cathode coupled to the second node, and a control terminal coupled to the third node. A transistor has a gate coupled to the first node. An anode of a diode at a first end of the n diodes is coupled to the first node, and a cathode of a diode at a second end of the n diodes is coupled to a third node.

An arc extinguishing power device driving apparatus and an arc extinguishing apparatus of the present disclosure belong to the electrical field, and are particularly an arc extinguishing power device driving apparatus applicable to an electronic arc extinguishing apparatus for driving a power device. The power device that needs to be driven is connected in parallel to a mechanical switch that requires arc extinguishing, and includes a first voltage detection switch. An input end of the first voltage detection switch is connected to two ends of the power device. The first voltage detection switch is connected in series in a driving loop of the power device. The first voltage detection switch is turned on when detecting that there is a potential difference between the two ends of the power device. A driving signal is transferred to the power device by using the first voltage detection switch, to drive the power device to be turned on. The first voltage detection switch is a semi-controllable switch, or a fully-controllable switch whose threshold is less than an on-state voltage of the power device. The present disclosure has advantages of no need of a semiconductor device with a high withstand voltage, real-time detection on disconnection of a mechanical switch, and low driving energy consumption.

A semiconductor relay device includes a conversion circuit configured to receive an input signal from outside and pass a first current to a first node based on the input signal. A zener diode has an anode coupled to a second node and a cathode coupled to the first node. A resistor is coupled between the second node and a third node. A number n of diodes are serially coupled. A thyristor has an anode coupled to the first node, a cathode coupled to the second node, and a control terminal coupled to the third node. A transistor has a gate coupled to the first node. An anode of a diode at a first end of the n diodes is coupled to the first node, and a cathode of a diode at a second end of the n diodes is coupled to a third node.