Abstract: The present disclosure provides a power electronic conversion unit and a power electronic conversion system. The power electronic conversion unit includes: two AC/DC subunits, AC ports of which are coupled in series to form a first port; two half-bridge subunits, DC ports of which are coupled to DC ports of the two AC/DC subunits, respectively; and a transformer, wherein two terminals of a primary winding of the transformer are coupled to a midpoint of bridge arms of the two half-bridge subunits. And a power electronic conversion system comprises a plurality of power electronic conversion units.

Abstract: A DC/DC converter includes: a first capacitor and a second capacitor coupled to a first node; a five-port network coupled to the first to fifth nodes; a transformer electrically connected to the fourth and fifth nodes; and a secondary side circuit electrically connected to a secondary winding of the transformer and coupled to a load; the control method includes: controlling, when the load is less than a preset value, switching states of multiple switches in the secondary side circuit, causing the transformer to be short-circuited for at least a first time period during a phase of stopping energy transmission; and controlling switching states of multiple switches in the five-port network during the first time period, causing current to flow from the five-port network to the first node or flow from the first node to the five-port network.

Abstract: A DC/DC converter includes a first capacitor and a second capacitor coupled to a first node, a first switch and a second switch coupled between the first node and a second node, a third switch and a fourth switch coupled between the first node and a third node, a first passive network coupled between a fourth node and a fifth node, the first passive network connecting the fourth node and the fifth node in series to a primary winding of a transformer, and a secondary side circuit coupled to a secondary winding of the transformer, a control method of the DC/DC converter includes: adjusting a phase shift angle between control signals of the first switch and the fourth switch to reduce a voltage difference between the first capacitor and the second capacitor.

Abstract: Embodiments provide a power electronic conversion unit and system, where the power electronic conversion unit includes an AC/DC subunit, which is a three-level circuit and includes a direct current output port; a first bus capacitor subunit and a second bus capacitor subunit are connected in series and connected to the direct current output port of the AC/DC subunit; the first DC/DC subunit includes a first and a second half-bridge DC/AC sub-modules, a first capacitor unit and a first transformer, where the first and second half-bridge DC/AC sub-modules has their direct current input ports connected to the first and second bus capacitor subunits in parallel, respectively; the first and the second half-bridge DC/AC sub-modules respectively include a bridge arm neutral point, and the first capacitor unit connects the bridge arm neutral points of the first and the second half-bridge DC/AC sub-modules and a primary winding of a first transformer in series.

Abstract: The present disclosure provides a power electronic conversion unit and a power electronic conversion system. The power electronic conversion unit includes: two AC/DC subunits, AC ports of which are coupled in series to form a first port; two half-bridge subunits, DC ports of which are coupled to DC ports of the two AC/DC subunits, respectively; and a transformer, wherein two terminals of a primary winding of the transformer are coupled to a midpoint of bridge arms of the two half-bridge subunits, And a power electronic conversion system comprises a plurality of power electronic conversion units.

Abstract: According to a first aspect of the present invention there is provided an apparatus for performing power equalization and phase correction of two signals (400). The apparatus comprises a first hybrid coupler (401) configured to operate as a power combiner, and a second hybrid coupler (402) configured to operate as a power divider, wherein the apparatus is configured to provide an output (406) of the first hybrid coupler as an input (407) to the second hybrid coupler.

Abstract: According to a first aspect of the present invention there is provided an apparatus for performing power equalisation and phase correction of two signals (400). The apparatus comprises a first hybrid coupler (401) configured to operate as a power combiner, and a second hybrid coupler (402) configured to operate as a power divider, wherein the apparatus is configured to provide an output (406) of the first hybrid coupler as an input (407) to the second hybrid coupler.