An integrated circuit includes a voltage regulating circuit in the form of only one transistor, or a group of several transistors in parallel, that are connected between first and second terminals configured to be coupled to an antenna. A control circuit operates to make the voltage regulating circuit inactive when a pulse generated by an electrostatic discharge event appears at one of the first and second terminals, regardless of the direction of flow of the pulse between the first and second terminals. An electrostatic discharge circuit is further provided to address the electrostatic discharge event.

A device comprises a rectifier configured to convert an alternating current voltage into a direct current voltage, a first overvoltage protection apparatus connected to inputs of the rectifier and a second overvoltage protection apparatus connected to an output of the rectifier, wherein the first overvoltage protection apparatus and the second overvoltage protection apparatus are controlled based upon a switching frequency of the device.

A system for control of a polyphase rotary electrical machine includes a stator provided with a plurality of phases, a synchronous rectifier bridge with a plurality of branches, each associated with a phase, each branch comprising a high transistor and a low transistor, a circuit for control of the high transistor, which can control a state of the said high transistor according to a difference between the positive potential and a reference voltage relative to the phase, a circuit for control of the low transistor, which can control a state of the said low transistor according to a difference between the phase voltage and a reference voltage relative to the negative potential, and, for each phase, a first protection device which is configured to permit a command for the low transistor to go to the switched-on state only if the phase voltage is lower than a threshold voltage.

An electrical assembly comprises a power converter including first and second DC terminals and an AC terminal. The electrical assembly also includes a grounding circuit to connect the AC terminal to ground. The grounding circuit defines first and second current flow paths between the AC terminal and ground. The first current flow path includes a switching element. The second current flow path includes a first current flow control element that is configured to operate in a first mode in which it reduce the flow of current between the AC terminal and ground when the first current flow path is open. The electrical assembly additionally includes a control unit configured to operate the switching element to maintain open the first current flow path following an occurrence of a DC network fault. The power converter is configured to continue transferring power between the DC and AC networks throughout the DC network fault.

A method for eliminating an arc driven by at least one phase voltage source of a converter circuit is disclosed. The converter circuit can include a converter unit and an energy storage circuit, wherein the at least one phase voltage source can be connected on an AC voltage side of the converter unit, and the converter unit can have a plurality of actuable power semiconductor switches. The method can include monitoring a state variable of the converter circuit for a predeterminable threshold value of the state variable to detect an arc, and actuating at least one of the plurality of actuable power semiconductor switches of the converter unit upon detecting a discrepancy between the state variable and the predeterminable threshold value.

An inrush current limiter circuit for a rectifier provides a flow of a current between a rectifying part of the rectifier and a filter capacitance. A power stage includes a power stage resistor and a power stage transistor disposed in parallel circuit arrangement to the power stage resistor. The power stage resistor conducts an amount of the current in dependence on the state of the power stage transistor, and the power stage transistor conducts an amount of the current in dependence on a charging of a gate capacitance of the power stage transistor.

A power converter includes an input voltage detection section, a power factor correction (PFC) section, a DC-DC conversion section, and a control section that stops power conversion operation in a case where an input voltage value is greater than or equal to a predetermined value. The control section resumes power conversion operation such that a second input current value lower than a first input current value corresponding to the input voltage value is input into the PFC section after stopping the power conversion operation.

Power converters, protection systems and methods to protect a precharge circuit in which a precharge resistor voltage is indirectly monitored during a normal operating mode, and a rectifier and an inverter are selectively disabled in response to the indirectly measured precharge resistor voltage indicating a fault in a precharge circuit SCR.

A variable frequency drive (VFD) circuit includes an input connectable to an AC source, a rectifier to convert an AC power input to a DC power, a DC link to receive DC power from the rectifier and having a DC link voltage thereon, a DC link capacitor bank with one or more capacitors connected to the DC link, and a pre-charge circuit coupled to the DC link capacitor. The pre-charge circuit further includes one or more resistors, one or more pre-charge relays each operable in on and off states to selectively control a current flow through the resistor(s) so as to control an initial pre-charge of the DC link capacitor, and an overvoltage relay operable in on and off states to selectively cut-off a current flow to the DC link capacitor bank, so as to prevent an overvoltage condition in the DC link capacitor bank.

An overvoltage protection circuit is provided which is connected between a rectifier circuit and a load including an input capacitor element connected to both ends of the load. The overvoltage protection circuit includes a semiconductor switch connected between the rectifier circuit and the load, and a control circuit controls the semiconductor switch. When the rectified voltage exceeds a predetermined value, the control circuit turns off the semiconductor switch, and detects a voltage potential difference between both ends of the semiconductor switch, and then, for an interval when the voltage potential difference is zero or a predetermined minute value, the control circuit generates a control voltage for turning on the semiconductor switch, and outputs the control voltage to a control terminal of the semiconductor switch. The overvoltage protection circuit includes a current change circuit that gradually changes a current flowing through the semiconductor switch.