For power transfer from a first DC part to a second DC part in a dual active bridge (DAB) converter by stepping up a voltage, the second bridge circuit 12 includes a period in which a secondary winding n2 of an insulated transformer TR1 and the second DC part conduct and a period in which ends of the secondary winding n2 of the insulated transformer TR1 are short-circuited in the second bridge circuit 12. A control circuit 13 fixes a phase difference between a first leg a the second leg, variably controls a simultaneous off period of a fifth switching element S5 and a sixth switching element S6, and variably controls a simultaneous off period of a seventh switching element S7 and an eighth switching element S8.

According to the integrated power conversion apparatus and method according to the exemplary embodiment of the present disclosure, the on-board battery charger (OBC), the lower voltage battery charger (LDC), and the traction converter (TC) are integrated to convert the power so that all the functions which need to be performed by the power conversion system of the related art can be performed. Further, the number of switches is reduced to increase a power density and not only the number of switches, but also the number of controllers is reduced to improve feasibility.

The present disclosure provides an isolated multi-phase DC/DC converter with a reduced quantity of blocking capacitors. In one aspect, the converter includes a multi-phase transformer having a primary circuit and a secondary circuit magnetically coupled to the primary circuit, the primary circuit having a first quantity of terminals, and the secondary circuit having a second quantity of terminals; a third quantity of blocking capacitors, each being electrically connected in series to a respective one of the terminals of the primary circuit; and a fourth quantity of blocking capacitors, each being electrically connected in series to a respective one of the terminals of the secondary circuit. The third quantity is one less than the first quantity. The fourth quantity is one less than the second quantity.

A variable voltage generator circuit is described for generating, from a substantially constant supply voltage V.sub.S, a variable high-voltage control voltage V.sub.C for a variable power capacitor (1) having a variable-permittivity dielectric. The control voltage generator circuit comprises a top-up circuit (10) for maintaining the voltage V.sub.Cin on an input capacitor (12) at least at supply voltage V.sub.S, and a bidirectional DC-DC converter circuit (20) having a variable voltage conversion factor G controlled by control input signal (27). The bidirectional DC-DC converter (20) is arranged to convert voltage, at the voltage conversion factor G, between the input capacitor voltage V.sub.Cin and the output voltage V.sub.C. When V.sub.C<G×V.sub.Cin, the DC-DC converter circuit (20) uses charge stored in the input capacitor (12) to charge the capacitive load (1). When V.sub.C>G×V.sub.Cin, the DC-DC converter circuit (20) uses charge stored in the load capacitance (1) to charge the input capacitor (12).

A power apparatus applied in a solid state transformer structure includes an AC-to-DC conversion unit, a first DC bus, and a plurality of bi-directional DC conversion units. First sides of the bi-directional DC conversion units are coupled to the first DC bus. Second sides of the bi-directional DC conversion units are configured to form at least one second DC bus, and the number of the at least one second DC bus is a bus number. The bi-directional DC conversion units receive a bus voltage of the first DC bus and convert the bus voltage into at least one DC voltage, or the bi-directional DC conversion units receive at least one external DC voltage and convert the at least one external DC voltage into the bus voltage.

The invention relates to a method and to a device for operating a bidirectional voltage transformer connectable to a primary battery and having a primary-side smoothing capacitor, an inductive transformer, and a secondary-side clamping capacitor, wherein, before the primary battery is connected, a voltage at the primary-side smoothing capacitor is matched to a voltage of the primary battery by a cyclical transfer of charge from the secondary-side clamping capacitor. The voltage of the primary-side smoothing capacitor is matchable in this way to the voltage of the primary battery before the primary battery is connected, and current spikes thus avoided during connection of the primary battery.

Compact light-weight on-board three-port power electronic system built in various configurations of triple-active-bridge-derived topologies, including modular implementations, with control strategies capable of bi-directional power transfer among the three ports of the power electronic system, including simultaneous charging of a high voltage (HV) battery and a low voltage (LV) battery from a single phase power grid or a three-phase power grid with minimized reactive power and active circulating current, with ensured soft-switching for MOSFET devices, and with enhanced synchronous rectification and reduced power losses.

A resonant converter and a manufacturing method of a transformer thereof are provided. The resonant converter includes a full bridge circuit, an element, a first branch circuit, a second branch circuit and a secondary winding. The full bridge circuit includes a first node and a second node. The element includes an inductor or a capacitor. The first branch circuit includes a first primary winding. The second branch circuit includes a second primary winding, and the first and second primary windings have the same turn number. The transformer is constructed by the first and second primary windings and the secondary winding. The first branch circuit, the element and the second branch circuit are sequentially coupled in series between the first and second nodes. The first branch circuit and the second branch circuit are symmetrically located with respect to the element. The first and second branch circuits have the same impedance.

The present disclosure provides a control method of a DC/DC converter and a related DC/DC converter. The control method allows for: detecting a difference between a first voltage and a second voltage; if an absolute value of the difference between the first voltage and the second voltage is greater than or equal to a preset value, reselecting desired operating states of respective switches in a 1-level state according to the difference between the first voltage and the second voltage and a direction of an average current from a fourth node to a first passive network in the 1-level state; and thus outputting a control signal to enable the voltage difference between the first capacitor and the second capacitor to be reduced, thereby effectively adjusting the neutral-point voltage balance of the DC/DC converter.

This power converter device is provided with a capacitor for smoothing a voltage entering therein; a first switching unit; a second switching unit; a reactor; an isolated transformer; a second capacitor; and a controller for controlling the switching of the first switching unit and the second switching unit; and the controller converting direct-current power to alternating-current power via the reactor and the isolated transformer, and converting said alternating-current power to direct-current power via the second capacitor; wherein, the controller includes a phase-shift operation unit for taking at least any of first switching control signals as a reference signal, and calculating a phase shift that shifts the phase of the reference signal; and a logic operation unit for performing a logic operation that takes the signal resulting from shifting the phase of the reference signal by exactly the phase shift as input and outputting a second switching control signal.