Provided are a power supply conversion circuit and a power supply conversion method. The power supply conversion circuit includes a first direct-current conversion circuit connected to an electric load, a secondary transformer coil connected to the first direct-current conversion circuit, and a primary transformer coil coupled to the secondary transformer coil. The primary transformer coil is configured to generate, based on an initial voltage inputted to the primary transformer coil, an electromagnetic field and couple the electromagnetic field to the secondary transformer coil. The secondary transformer coil is configured to generate an induced current by virtue of the electromagnetic field, generate a secondary output voltage based on the induced current, and transmit the secondary output voltage to the first direct-current conversion circuit. The first direct-current conversion circuit is configured to adjust, based on a predetermined demand voltage of the electric load, the secondary output voltage to obtain a target voltage.

Provided by the present disclosure are a power supply circuit and a charging device. The power supply circuit comprises a pulse transformer circuit and a first power supply conversion circuit. The pulse transformer circuit comprises a pulse transformer and a switch control circuit; a primary winding of the pulse transformer is connected to a power supply and is connected to the switch control circuit, and the switch control circuit is used to modulate the voltage on the primary winding into a pulse voltage; and the input terminal of the first power supply conversion circuit is connected to a secondary winding of the pulse transformer, and is used to transform the voltage on the secondary winding of the pulse transformer into a first preset voltage range when the voltage outputted by the secondary winding exceeds the first preset voltage range, and then output the voltage.

Provided by the present disclosure are a power supply circuit and a charging device. The power supply circuit comprises a pulse transformer circuit and a first power supply conversion circuit. The pulse transformer circuit comprises a pulse transformer and a switch control circuit; a primary winding of the pulse transformer is connected to a power supply and is connected to the switch control circuit, and the switch control circuit is used to modulate the voltage on the primary winding into a pulse voltage; and the input terminal of the first power supply conversion circuit is connected to a secondary winding of the pulse transformer, and is used to transform the voltage on the secondary winding of the pulse transformer into a first preset voltage range when the voltage outputted by the secondary winding exceeds the first preset voltage range, and then output the voltage.

This application discloses a drive circuit of a bridge arm switching transistor, a drive circuit, and a power converter. The bridge arm switching transistor includes a first switching transistor and a second switching transistor. A first terminal of the first switching transistor is connected to a power supply, a second terminal of the first switching transistor is connected to a first terminal of the second switching transistor, and a second terminal of the second switching transistor is grounded. The drive circuit includes a low-voltage region and at least two high-voltage regions isolated which include a first high-voltage region and a second high-voltage region. A semiconductor device configured to drive the second switching transistor is disposed in the low-voltage region. P-type semiconductor devices are disposed in each of the first high-voltage region and the second high-voltage region, and the P-type semiconductor devices are configured to drive the first switching transistor.

A load control device for controlling power delivered from an AC power source to an electrical load may have a closed-loop gate drive circuit for controlling a semiconductor switch of a controllably conductive device. The controllably conductive device may be coupled in series between the source and the load. The gate drive circuit may generate a target signal in response to a control circuit. The gate drive circuit may shape the target signal over a period of time and may increase the target signal to a predetermined level after the period of time. The gate drive circuit may receive a feedback signal that indicates a magnitude of a load current conducted through the semiconductor switch. The gate drive circuit may generate a gate control signal in response to the target signal and the feedback signal, and render the semiconductor switch conductive and non-conductive in response to the gate control signal.

A load control device for controlling power delivered from an AC power source to an electrical load may have a closed-loop gate drive circuit for controlling a semiconductor switch of a controllably conductive device. The controllably conductive device may be coupled in series between the source and the load. The gate drive circuit may generate a target signal in response to a control circuit. The gate drive circuit may shape the target signal over a period of time and may increase the target signal to a predetermined level after the period of time. The gate drive circuit may receive a feedback signal that indicates a magnitude of a load current conducted through the semiconductor switch. The gate drive circuit may generate a gate control signal in response to the target signal and the feedback signal, and render the semiconductor switch conductive and non-conductive in response to the gate control signal.

A rectifier circuit has one or more bridge circuits each with: a first leg with two diodes in series and an AC terminal at a midpoint between the two, a second leg with two semiconductor switches in parallel to the first, a third diode connected to a upper node of each leg, a fourth diode connected to a lower node of each leg, and a capacitor leg with two capacitors in series between the third and fourth diode. A midpoint between the capacitors is connected to a midpoint between the semiconductor switches. The first arrangement is two controllable semiconductor switches in series. A gate node of the second is connected to a first load terminal of the first switch and the first load terminal is connected to the lower node. The second semiconductor switch is a third controllable semiconductor switch with a gate node connected to the lower node.

A rectifier circuit has one or more bridge circuits each with: a first leg with two diodes in series and an AC terminal at a midpoint between the two, a second leg with two semiconductor switches in parallel to the first, a third diode connected to a upper node of each leg, a fourth diode connected to a lower node of each leg, and a capacitor leg with two capacitors in series between the third and fourth diode. A midpoint between the capacitors is connected to a midpoint between the semiconductor switches. The first arrangement is two controllable semiconductor switches in series. A gate node of the second is connected to a first load terminal of the first switch and the first load terminal is connected to the lower node. The second semiconductor switch is a third controllable semiconductor switch with a gate node connected to the lower node.

A DC-link charging arrangement is described having a DC-link capacitor, rectifier means, and contactor means arranged between supply voltage ports and the rectifier means and having at least one contactor. Such a charging arrangement should enable charging of a DC-link capacitor in a simple way with low losses. To this end a charging capacitor is arranged bridging the at least one contactor.

A DC-link charging arrangement is described having a DC-link capacitor, rectifier means, and contactor means arranged between supply voltage ports and the rectifier means and having at least one contactor. Such a charging arrangement should enable charging of a DC-link capacitor in a simple way with low losses. To this end a charging capacitor is arranged bridging the at least one contactor.