A system and method for maintaining electrical stability of a high-voltage transmission power system in response to a fault. The method includes detecting the fault, opening a switch to clear the fault, performing a first pulse test for a predetermined duration of time to determine if the fault is still present, preventing a reclosing operation from occurring if the pulse test indicates that the fault is still present, and allowing the reclosing operation to occur if the first pulse test indicates that the fault is not present. One or more subsequent pulse tests can be performed if the first pulse test is inclusive about the persistence of the fault, where the reclosing operation is prevented from occurring if the pulse tests indicate that the fault is still present and the reclosing operation is allowed if the pulse tests indicate that the fault is no longer present.

A pre-charge control circuit includes a control unit, a conversion unit, and a pre-charge switch. The control unit provides a control signal according to a PWM signal, and the conversion unit provides a control voltage according to the control signal. The pre-charge switch adjusts a magnitude of the current flowing through the input path of the electronic circuit according to the control voltage.

A semiconductor integrated circuit device includes a control unit configured to control a switching element or an output transistor of a power supply device, a monitor terminal for monitoring an output voltage of the power supply device, a test unit configured to output a test signal to the monitor terminal before activation of the power supply device, and a determination unit configured to determine whether or not the monitor terminal is open, on the basis of a voltage of the monitor terminal when the test unit outputs the test signal to the monitor terminal.

A method for automatically testing a relay is provided. The method includes applying power to a testing device for automatically testing the relay, determining a position of a selector switch based on a user selection for testing, selectively energizing the relay based on the position of the selector switch, detecting, by a hardware processor, an energize status signal from the selector switch, testing, by the hardware processor and based at least on the energize status signal, a control coil or a contact of the relay to generate a test result, and displaying, using display, the energize status signal and the test result.

A method for automatically testing a relay is provided. The method includes applying power to a testing device for automatically testing the relay, determining a position of a selector switch based on a user selection for testing, selectively energizing the relay based on the position of the selector switch, detecting, by a hardware processor, an energize status signal from the selector switch, testing, by the hardware processor and based at least on the energize status signal, a control coil or a contact of the relay to generate a test result, and displaying, using display, the energize status signal and the test result.

A control circuit of a power conversion apparatus is provided with a switch driving unit that drives the upper and lower arm switches; a short circuit control unit that causes the switch driving unit to execute a short circuit control when a failure occurs in the system, the short circuit control turning an ON side switch to an ON state and turning an OFF side switch to an OFF state; a checking unit that executes a checking process to check whether the short circuit control is able to perform correctly; and a protection control unit that causes the switch driving unit to execute a protection control when a failure occurs on either the upper arm switch or the lower arm switch, the protection control turning the switch where the failure occurs to an OFF state. The control circuit enables the protection control during execution of the checking process.

In an embodiment an isolated gate driver device includes a low-voltage section having a control input configured to receive a PWM control signal with a switching frequency from a control stage, a high-voltage section, galvanically isolated from the low-voltage section the high-voltage section including a driving output configured to provide a gate-driving signal as a function of the PWM control signal to a power stage having at least one switch, a feedback input configured to receive at least one feedback signal indicative of an operation of the power stag, and an ADC module configured to convert the feedback signal into a digital data stream and a conversion-control module coupled to the ADC module and configured to provide a conversion-trigger signal designed to determine a start of a conversion for acquiring a new sample of the feedback signal.

An electronic fuse circuit includes an electronic switch with a load current path coupled between an output node and a supply node and that connects or disconnects the output node and the supply node in accordance with a drive signal. The circuit includes a control circuit to generate the drive signal based on an input signal. A monitoring circuit is included in the control circuit to receive a current sense signal representing the load current passing through the load current path and to determine a first protection signal based on the current sense signal and a wire parameter. The first protection signal is indicative of whether to disconnect the output node from supply node. The control circuit changes from normal mode to idle mode when the load current is below a given current threshold and another criterion is fulfilled.

A method for monitoring a switchable semiconductor component having a protective circuit connected in parallel to the semiconductor component includes tapping an electrical variable applied to the semiconductor component and the protective circuit, and detecting damage to the semiconductor component and/or the protective circuit when an electrical variable is greater than a previously known critical value.

According to one embodiment, a multichannel switch integrated circuit (IC) includes a multichannel switch circuit and a common test terminal. The multichannel switch circuit includes a plurality of switch circuitries. Each of the switch circuitries includes: an output transistor that outputs an output signal through an output terminal; an overcurrent detection circuit that detects a detection current according to a current flowing through the output transistor; and a diode having an anode that receives the detection current. The common test terminal is connected to each channel switch circuitry, connected to the overcurrent detection circuit through the diode, and connected to a cathode of the diode.