A low-voltage circuit in a bidirectional DC-DC converter converts output AC power from a high-voltage circuit to DC power to charge a smoothing reactor and discharge the smoothing reactor, and includes an active snubber circuit including switching elements and each having a backward diode and a snubber capacitor. The snubber capacitor of the active snubber circuit has its one end connected to a drain end of the switching elements and has its other end connected to a node between a center tap of a high-frequency transformer and a smoothing reactor.

The invention relates to a device (200) for measuring a current through a choke (130) of a voltage converter (100) comprising an integrator circuit (140), an amplifier circuit and an NTC resistor (160). The amplifier circuit comprises an inverting and a non-inverting amplifier input connection (152, 154) and an amplifier output connection (156). The non-inverting amplifier input connection (154) is supplied with an amplifier input signal according to an integrator output signal. A voltage signal characterising the current through the choke (130) is applied at the amplifier output connection (156) of the amplifier circuit. The NTC resistor (160) is arranged in the feedback path of the amplifier circuit between the inverting amplifier input connection (152) and the amplifier output connection (156).

A power converter configured to be connected to three or more voltage parts, includes three or more power-conversion circuitries to be connected to respective ones of the three or more voltage parts, and a multi-port transformer connected to the three or more power-conversion circuitries at respectively different ports. The three or more voltage parts include a vehicle drive battery and a plurality of alternating-current (AC) voltage parts. Each of the plurality of AC voltage parts is configured to provide at least one of power input to a multi-port transformer side and power output from the multi-port transformer side.

This control device is configured to control a converter comprising a piezoelectric element and several switches, and capable of delivering N output voltage(s) from of E input voltage(s), E≥1, N≥1.

The control device comprises a module for controlling, during a respective resonance cycle of the piezoelectric element, switching of the switches to alternate phases at substantially constant voltage and phases at a substantially constant charge at the terminals of the piezoelectric element, each cycle comprising first and second half-cycles, a current flowing in one direction in the piezoelectric element during first half-cycle and in an opposite direction during the second half-cycle.

The number of substantially constant voltage phases during a cycle is greater than or equal to E+N+2, and each of the half-cycles comprises at least two substantially constant voltage phases.

The application provides a current detecting circuit, including a current transformer having a primary winding for receiving a current to be detected and a secondary winding for generating a sampling current; a demagnetizing circuit for demagnetizing the current transformer; a chip selection circuit electrically connected to the demagnetizing circuit, and operably switched between a first mode and a second mode; a sampling circuit electrically connected to the chip selection circuit to sample the sampling current, and outputting a sampling signal to a controller; and a clamping circuit electrically connected between the sampling circuit and the controller, and configured for providing a reference potential. The application further provides a converter including the current detecting circuit.

Disclosed herein is a charger capable of bidirectional power transfer. A power factor compensation circuit converts a multi-phase AC voltage into a DC voltage and includes a plurality of inductors and a plurality of switching elements. The DC voltage converted by the power factor compensation circuit is applied to a DC link capacitor. A bidirectional DC converter bidirectionally converts the magnitude of a voltage between the DC link capacitor and a battery. In DC power supply mode, a controller controls the bidirectional DC converter to convert a magnitude of a voltage of the battery to apply the voltage of the battery to the DC link capacitor and controls the plurality of switching elements to generate a DC supply voltage by converting the magnitude of the DC voltage of the DC link capacitor and output the DC supply voltage through a terminal through which the multi-phase AC voltage is input.

An embodiment charging device includes a power factor correction circuit first to third switch legs connected to first to third inductors, respectively, a relay network for controlling connection between the first to third inductors and first to third input terminals according to a phase of a power grid connected to the first to third input terminals, a relay control circuit connected to the first to third input terminals for sensing one of the first to third input terminals to which a power source is connected and controlling the relay network based on a sensing result, and a relay filter circuit including first to third filter capacitors connected between a ground plane and first to third sensing lines connected to the relay control circuit for sensing voltages of the first to third input terminals and a fourth filter capacitor connected between the ground plane and a chassis.

A system for an AC to DC PFC converter includes a first phase switch group connected to a first node to receive power from a first phase of a voltage source; a second phase switch group connected to a second node to receive power from a second phase of the voltage source; a third phase switch group connected to a third node to receive power from a third phase of the voltage source; a neutral phase switch group connected to a fourth node to be connected to a ground terminal of the voltage source; a first switch connected to the first node and the second node; and a second switch connected to the second node and the third node.

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.

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.