A power converter arrangement including a semiconductor switch system including at least one controllable switch, a capacitor unit including at least one capacitor having a capacitance value, the capacitor unit being operatively connected to the semiconductor switch system, a conductor arrangement including of at least one conductor adapted to conduct an electric current between the capacitor unit and the semiconductor switch system, wherein the at least one conductor having a resistance and an inductance, and wherein a resonant circuit is formed by the resistance, the inductance and the capacitance, and wherein the power converter arrangement includes at least one attenuating element for attenuating an electrical ringing in the resonant circuit, wherein the at least one attenuating element is conductively isolated from the resonant circuit, and wherein the at least one attenuating element includes ferromagnetic material, and wherein the at least one attenuating element is magnetically coupled to the at least one conductor such that variations in the electric current intensity of the at least one conductor induces eddy currents within the at least one attenuating element.

A power converter includes an energy transfer element coupled between an input of the power converter and an output of the power converter. A control switch is coupled to a normally-on switch. The normally-on switch is coupled to the energy transfer element. A controller is coupled to control switching of the control switch to control a transfer of energy from the input of the power converter to the output of the power converter. The controller includes a drive circuit coupled to generate a drive signal in response to a control signal to control switching of the control switch. The drive signal in a first stage of a multiple stage gate drive is coupled not to fully enhance the control switch. The drive signal provided by a second stage of the multiple stage gate drive is coupled to fully enhance the control switch.

Effects of a surge in an AC input voltage to a UPS is mitigated. If the AC input voltage is overvoltage, the rectifier is operated using a DC bus target voltage for the DC bus voltage unless the rectifier reaches its current limit. If the rectifier reaches its current limit, the DC bus target voltage is increased by a predetermined amount which is used as a current DC bus target voltage unless the increased DC bus target voltage exceeds a maximum DC bus voltage limit in which case the current DC bus target voltage is set to the maximum DC bus voltage limit. The rectifier is then operated using the current DC bus target voltage until it reaches its current limit or the AC input voltage surge has passed. If the rectifier again reaches its current limit, the above steps starting with increasing the DC bus target voltage are repeated.

An embodiment of the present application provides a voltage conversion device configured to convert an inputted alternating voltage into a direct voltage or current, the voltage conversion device including at least a first voltage connector and a second voltage connector, where the alternating voltage is fed to the voltage conversion device via either the first voltage connector or the second voltage connector, the voltage conversion device further including: an electromagnetic filter unit; a conversion unit; a determination unit configured to determine which one of the first voltage connector and the second voltage connector is used to feed the alternating voltage into the voltage conversion device; a control unit controlling the conversion unit based on a determination result of the determination unit such that the direct voltage or current outputted by the conversion unit corresponds to the determination result, wherein the determination unit is electrically connected the first voltage connector and the second voltage connector. This application can determine a voltage connector for feeding via a simple circuit and can perform corresponding control to output a corresponding direct voltage or current.

A semiconductor device includes: parasitic inductances connected to respective power transistors; and a drive circuit connected to connection points at which the power transistors are connected to the respective parasitic inductances, and driving the power transistors. The drive circuit insulates reference potentials of the power transistors at the connection points from each other.

The present disclosure relates to a method and apparatus for charging and discharging. The apparatus includes: an AC power terminal, including first to third nodes, and a first center line node, and being configured to receive input an AC input or send an AC output; a power conversion stage, including fourth to sixth nodes, and a second center line node; a first bus capacitor and a second bus capacitor both coupled to the second center line node, the first center line node being coupled to the second center line node; a first switch set; a second switch set; a control module, coupled to the first switch set, the second switch set, the AC power terminal, and the power conversion stage.

A bidirectional switch for the control of power from an AC source to a load is described. The approach uses power MOSFETs in a bidirectional switch subcircuit configuration having an optically coupled, electrically floating control circuit that self-biases the switches into the on state and uses an optically coupled control element to force the switches into the off state. The time constant of the control circuit is fast enough to allow phase control as well as on-off control. A boost circuit is included to ensure that the control voltage exceeds a threshold voltage of the MOSFETs to force an off state. A plurality of subcircuits can be easily cascaded to provide improved performance.

[Object] [Solving Means] A discharge device includes a discharge unit and a cut-off detection unit. The discharge unit is configured to discharge a capacitor at a variable discharge current value on the basis of a voltage of a rectified signal obtained by full-wave rectifying an AC voltage input via an input filter including the capacitor. The cut-off detection unit is configured to monitor the voltage of the rectified signal and to detect whether or not a power supply is cut off on the basis of a change of the voltage when the capacitor is discharged by the discharge unit at a specific discharge current value.

Provided is a premagnetization device for a converter system that is connectable to a three-phase electrical grid that has a three-phase power transformer, a converter connected to the power transformer and a circuit-breaker on the grid side of the power transformer. The premagnetization device is premagnetizes the power transformer in a state isolated from the grid. The premagnetization device uses a single-phase reference voltage (Uref) that has a fixed relationship to the grid voltage (Ugrid) with regard to the voltage parameters, in order to generate, based on the measured instantaneous reference voltage (Uref) and the known fixed parameter relationships, by actuating the converter, a three-phase alternating voltage synchronous to the grid voltage (Ugrid) on the grid side of the power transformer.

A power adapter is provided to supply electric power from an alternating current from an alternating current (AC) power supply to a powered apparatus. It includes a switchable capacitor circuit housed within a housing and including: a first switch path associated with a positive half cycle of the alternating current and a second switch path associated with a negative half cycle of the alternating current, both coupled across the AC power supply. Each switch path includes a switchable capacitor in series with a switch.