A power inverter topology for converting a DC input to one or more phases of AC output, and methods for operating the same. The power inverter includes a switching circuit, an input circuit and a freewheeling diode bridge arrangement. The switching circuit comprises switch arms extending between the upper and lower branches of the switching circuit. The input circuit includes upper and lower isolating switches that can be selectively operated to respectively isolate the upper and/or lower branches of the switching circuit.

A wireless power receiver includes a rectifier with first and second inputs coupled to first and second terminals of a receiver coil, and having a first output coupled to ground and a second output at which a rectified voltage is produced. A first switch is coupled between the second input and ground, and is controlled by a first gate voltage generated at a first node. A second switch is coupled between the first node and ground, and is controlled by a second gate voltage. The first gate voltage closes the first switch to couple the second input to ground when the rectified voltage is less than a threshold voltage, boosting the rectified voltage. The second gate voltage closes the second switch to cause the second gate voltage to be pulled to ground when the rectified voltage is greater than the threshold voltage, limiting the boosting of the rectified voltage.

A controller for a boost power factor correction (PFC) converter. The controller is configured to operate the boost PFC converter in multiple operating modes, including a continuous conduction mode (CCM), a transition mode (TM), and a hybrid mode in which the controller operates the converter in both CCM and TM within a same line cycle. An example controller includes a current control loop and a mode transition circuit. The current control loop is configured to compute an inductor current for each of first and second operation modes, based on a current sample taken, for example, during a boost synchronous rectifier conduction period of the converter. The mode transition circuit includes digital logic circuitry and is configured to generate a pulse indicating that one, two or all three of: zero-voltage switching (ZVS) has been achieved; the synchronous rectifier conduction period is active; and/or one of TM or hybrid mode is active.

Techniques for converting power received from a power grid at a first voltage and outputting a signal at a second voltage are discussed herein. A power converter with a transformer that has a 22.5 degrees phase shift between current output by corresponding pairs of secondary windings can be utilized to convert power of a first level to power of a second level. The transformer can output power from 30 secondary windings. The power converter can output power with a total harmonic distortion of 5% and an efficiency of 96% or higher. Further, power can be output by a transmission coil and received by a receive coil in a device, such as a vehicle, to wirelessly charge the vehicle.

The present disclosure relates to an uninterruptible power supply (UPS) system and, more specifically, to a static transfer switch (STS) that can be applied to a UPS module, the static transfer switch comprising: one semiconductor rectifying element connected to either the anode terminal or the cathode terminal of a direct current power source; a bypass circuit for connecting the input terminal and the output terminal of the semiconductor rectifying element so as to bypass the semiconductor rectifying element; a breaker for opening or closing the bypass circuit; and a switch including a control unit, which controls the semiconductor rectifying element so as to conduct current when a preset conduction signal is received, controls the breaker so as to close the bypass circuit, and, when the bypass circuit is closed by the breaker, controls the semiconductor rectifying element so as to stop the conduction of current.

An example welding-type power supply includes: power conversion circuitry configured to convert three-phase input power to welding-type power; a reference node coupled to each winding of the three-phase input power via a corresponding impedance; and a phase detection circuit coupled to the reference node and configured to determine a number of phases connected to the input based on comparing a frequency of a signal at the reference node to a threshold frequency.

An example welding-type power supply includes: power conversion circuitry configured to convert three-phase input power to welding-type power; a reference node coupled to each winding of the three-phase input power via a corresponding impedance; and a phase detection circuit coupled to the reference node and configured to determine a number of phases connected to the input based on comparing a frequency of a signal at the reference node to a threshold frequency.

An on-board charger is provided with a bulk capacitor adapted to couple to a vehicle traction battery and a relay for receiving electrical power from an external power supply and to pre-charge the bulk capacitor. A power factor correction (PFC) circuit is connected between the bulk capacitor and the relay. The PFC circuit includes a switch that is adjustable between an on-position and an off-position. The switch enables current flow from the relay to the bulk capacitor in the off-position. A snubber circuit is coupled to the switch to damp a transient voltage present at the switch during a transition from the on-position to the off-position. A processor is programmed to control the switch.

A method for controlling a power conversion device can prevent over temperature by suppressing a change in impedance of a capacitor included in a rectifier circuit. The power conversion device includes an AC wave generation circuit for generating an AC wave, and a rectifier circuit for rectifying the AC wave generated by the AC wave generation circuit with a configuration including a rectifier capacitor and a diode connected in parallel. The method for controlling the power conversion device regulates the AC wave input to the rectifier capacitor depending on a change in impedance of the rectifier capacitor so as to suppress the change in the impedance of the rectifier capacitor.

A switching device is provided. The apparatus includes a switching circuit and a noise filter. The switching circuit is capable of switching a connection destination of a first power conversion circuit other than a second power conversion circuit among the plurality of power conversion circuits between a phase corresponding to the first power conversion circuit and a certain phase of the external power supply. The second power conversion circuit corresponds to the certain phase of the external power supply. In the noise filter, a capacitor is provided on a side of the multiple-phase AC supply of the switching circuit.