An electronic apparatus includes: an operator; and a power circuit configured to supply power to the operator, wherein the power circuit includes a first voltage converter configured to output a first voltage based on input power, and a power factor corrector (PFC) configured to output a second voltage by performing power factor correction for the first voltage, and supplies power based on the first voltage or the second voltage to the operator, wherein the power circuit stops an operation of the PFC, lowers the first voltage to have a level corresponding to the second voltage, and supplies power based on the lowered first voltage to the operator, based on power consumption of the operator lower than or equal to a predetermined value.

A magnetic device includes a winding, and insulators by which the winding is surrounded. Each of the insulators is in contact with the winding. A gap exists between each two adjacent of the insulators in a winding direction of the winding.

The isolation transformer includes two kinds of winding, a high voltage side winding and a low voltage side winding, and the high voltage side winding and the low voltage side winding are formed in winding layers, wherein the high voltage side winding includes windings formed in multiple winding layers, a winding layer having a different number of turns exists in one or more kinds of the two kinds of winding among the windings formed in the multiple winding layers, winding layers wherein current flows in the same direction are stacked in such a way as not to be neighboring, and at least one of winding layers having the greatest number of turns is disposed as a layer other than an outermost layer.

A DC-DC converter includes a first switching network that receives the input DC voltage and outputs a first AC voltage, a transformer, and a secondary side conversion circuit that receives the second AC voltage and outputs the output DC voltage. The transformer includes a first plurality of primary windings, a second plurality of primary windings and a plurality of secondary windings. The transformer is configured to receive the first AC voltage and outputting a second AC voltage. When the input DC voltage is intended to be used in a low voltage range, the first plurality of primary windings and the second plurality of primary windings are configured to be in parallel at the time the DC-DC converter is manufactured. When the input DC voltage is intended to be used in a high voltage range the first plurality of primary windings and the second plurality of primary windings are configured to be in series at the time of manufacture.

Various embodiments are directed to a voltage clamp system comprising: a rectifier; a protected node, a reference node, and one or more internal nodes, coupled to the rectifier; a power converter, coupled to the rectifier via the one or more internal nodes; and one or more output nodes coupled to the power converter and configured to couple to a power sink. The rectifier and the power converter are configured to output power via one or more output nodes coupled to the rectifier, and to limit a component of the voltage between the protected node and the reference node.

A controller of a power converter is coupled to a switch assembly and configured to perform a hold-up time procedure that causes the controller to control first and second switching elements into opposite conducting states during a first period of time of a pulse cycle and into alternate opposite conducting states during a second period of time of the pulse cycle. The hold-up time procedure also causes the controller to control a first pair of synchronous rectifier switching devices into a conducting state during a third period of time overlapping less than all of the first period of time and into the conducting state during a fourth period of time overlapping less than all of the second period of time. A second pair of synchronous rectifier switching devices is controlled into a non-conducting state during the first and second periods of time.

A crystal that is useful for semiconductor element and a semiconductor element that has enhanced electrical properties are provided. A crystal, including: a corundum structured crystalline oxide, the crystalline oxide including gallium and/or indium, and the crystalline oxide further including a metal of Group 4 of the periodic table. The crystal is used to make a semiconductor element, and the obtained semiconductor element is used to make a semiconductor device such as a power card. Also, the semiconductor element and the semiconductor device are used to make a semiconductor system.

A three-phase AC to DC converter includes a first converter stage for converting between three phase voltages at three phase terminals and a first signal at a first intermediate node and a second intermediate node. A phase selector is configured to selectively connect the three phase terminals to a third intermediate node. The converter includes a second converter stage, a DC link connecting the first and second converter stages, and a galvanically isolated DC/DC converter stage having a first side connected to output nodes of the second converter stage and a first common node. A second side of the DC/DC converter stage is galvanically isolated from the first side. The first common node is connected to the third intermediate node. The difference of a first current applied to the DC/DC converter at output nodes of the second converter stage is provided at the third intermediate node.

A power conversion device includes a filter circuit unit between a power conversion unit and a smoothing capacitor for smoothing a pulsating flow accompanying power conversion in the power conversion unit to absorb at least a part of a high-frequency component of the pulsating flow.

The present invention relates to the control of a dual active bridge converter. In particular, it is provided that a control variable for the dual active bridge converter is superimposed with an additional ripple component and to control the dual active bridge converter with a combination of the control variable and the additional ripple component.