This uninterruptible power supply device includes an input module provided with a plurality of conductor wires having a plate shape including at least a plurality of AC input wires, and an uninterruptible power supply module. In addition, the plurality of AC input wires each extend in an X direction in which the uninterruptible power supply module and the input module are adjacent to each other, and have AC input cable attachment portions in which an AC input cable is attached. The AC input cable attachment portions are disposed so as to be separated from each other in a Y direction, which is a direction in which a front side and a rear side of the input module face each other.

A voltage conversion system includes an energy storage device; a power conversion unit connected to the energy storage device, the power conversion unit comprising: an inductor, the inductor comprising a number of coils that are non-coupled or weakly coupled, with a coupling coefficient less than 0.05; a multi-phase boost stage coupled to the inductor, wherein the multiphase boost stage comprises a number of phases that equals the number of coils; an inverter coupled to the multiphase boost stage; and a load coupled to the power conversion unit.

A voltage conversion system includes an energy storage device; a power conversion unit connected to the energy storage device, the power conversion unit comprising: an inductor, the inductor comprising a number of coils that are non-coupled or weakly coupled, with a coupling coefficient less than 0.05; a multi-phase boost stage coupled to the inductor, wherein the multiphase boost stage comprises a number of phases that equals the number of coils; an inverter coupled to the multiphase boost stage; and a load coupled to the power conversion unit.

Circuitry for reducing the energy losses of a snubber circuit used to protect current switching devices from overvoltage, comprising a switching cell consisting of a switch with alternating opposite conduction states, the switch being serially connected via one contact to a first diode, the switch includes an inherent output capacitance, the switch connects, via a first stray inductance), between one port of a power supply and an output inductor feeding a load, and the first diode connects, via a second stray inductance, between the other port of the power supply and the output inductor, such that whenever the switch passes from a conducting state to a non-conducting state, its inherent output capacitance is charged by a current pulse from the first stray inductance; a snubber circuit consisting of a ferrite bead, a snubber capacitor and a second diode, the snubber circuit being connecting between the other contact of the switch and the other port, for discharging at least a portion of the charge across the inherent output capacitance of the switch to the snubber capacitor via the other port.

Circuitry for reducing the energy losses of a snubber circuit used to protect current switching devices from overvoltage, comprising a switching cell consisting of a switch with alternating opposite conduction states, the switch being serially connected via one contact to a first diode, the switch includes an inherent output capacitance, the switch connects, via a first stray inductance), between one port of a power supply and an output inductor feeding a load, and the first diode connects, via a second stray inductance, between the other port of the power supply and the output inductor, such that whenever the switch passes from a conducting state to a non-conducting state, its inherent output capacitance is charged by a current pulse from the first stray inductance; a snubber circuit consisting of a ferrite bead, a snubber capacitor and a second diode, the snubber circuit being connecting between the other contact of the switch and the other port, for discharging at least a portion of the charge across the inherent output capacitance of the switch to the snubber capacitor via the other port.

In one form, a method of manufacturing a circuit device comprises providing a lead frame comprising a plurality of leads, each comprising an island portion, a bonding portion elevated from the island portion, a slope portion extending obliquely so as to connect the island portion and the bonding portion, and a lead portion extending from the bonding portion. First and second transistors and first and second diodes are mounted upper surfaces of island portions of respective first and second leads, and are connected to the respective leads through wirings that connect the transistors and diodes to the bonding portions of the respective leads. Lower surfaces of the island portions are attached to an upper surface of a circuit board, and the circuit board, the transistors, the diodes, and the lead frame are encapsulated by a resin, so that the lead portions are not covered by the resin.

In one form, a method of manufacturing a circuit device comprises providing a lead frame comprising a plurality of leads, each comprising an island portion, a bonding portion elevated from the island portion, a slope portion extending obliquely so as to connect the island portion and the bonding portion, and a lead portion extending from the bonding portion. First and second transistors and first and second diodes are mounted upper surfaces of island portions of respective first and second leads, and are connected to the respective leads through wirings that connect the transistors and diodes to the bonding portions of the respective leads. Lower surfaces of the island portions are attached to an upper surface of a circuit board, and the circuit board, the transistors, the diodes, and the lead frame are encapsulated by a resin, so that the lead portions are not covered by the resin.

A discharging method of a bus capacitor, a controller, a DC-DC converter and an inverter are provided. After a DC-DC converter or an inverter is powered off, in a case that a detected voltage across a bus capacitor of the DC-DC converter or the inverter is determined to meet a preset condition, a switch of the DC-DC converter or the inverter is controlled to be turned on or turned off to cause the bus capacitor, the switch, and a reactor of the DC-DC converter or the inverter to form a current loop, until the voltage does not meet the preset condition. Based on the method, discharging function is achieved for the bus capacitor after the DC-DC converter or the inverter is powered off, without the need for an additional discharging circuit, which solves problems caused by the additional discharging circuit required in the conventional technology.

A discharging method of a bus capacitor, a controller, a DC-DC converter and an inverter are provided. After a DC-DC converter or an inverter is powered off, in a case that a detected voltage across a bus capacitor of the DC-DC converter or the inverter is determined to meet a preset condition, a switch of the DC-DC converter or the inverter is controlled to be turned on or turned off to cause the bus capacitor, the switch, and a reactor of the DC-DC converter or the inverter to form a current loop, until the voltage does not meet the preset condition. Based on the method, discharging function is achieved for the bus capacitor after the DC-DC converter or the inverter is powered off, without the need for an additional discharging circuit, which solves problems caused by the additional discharging circuit required in the conventional technology.

A drive circuit includes a first driver to control on/off of an upper arm, a second driver to control on/off of a lower arm, a first switching device including a first terminal connected with a power supply for the first driver, a second terminal connected with a power supply for the second driver and a control terminal, a booster circuit to turn on the first switching device by boosting a control signal which is at a high level when the lower arm is in an on state, a second switching device to cause continuity between the control terminal and the booster circuit when the control signal is at the high level, and first switch unit to short-circuit the control terminal and the terminal for grounding when the control signal is at the low level.