A power conversion apparatus includes: a first stage on which a first module is mounted, a second stage stacked on the first stage and on which a second module is mounted, and a coolant circulation circuit allowing a coolant to circulate through the first and second modules. The coolant circulation circuit includes a first cooling pipe disposed on the first stage, a second cooling pipe disposed on the second stage, a first connecting member provided at an opening end of the first cooling pipe, a second connecting member provided at an opening end of the second cooling pipe, a connecting pipe connecting the first connecting member and the second connecting member, a first coupler that couples a first end portion of the connecting pipe to the first connecting member, and a second coupler that couples a second end portion of the connecting pipe to the second connecting member.

A converter includes first and second transistors coupled between first and second nodes, and first and second thyristors coupled between the first and second nodes. The converter is controlled for operation to: in first periods, turn the first transistor and second thyristor on and turn the second transistor and the first thyristor off, and in second periods, turn the first transistor and the second thyristor off and turn the second transistor and the first thyristor on. Further control of converter operation includes, for a third period following each first period, turning the first and second transistors off, turning the second thyristor off, and injecting a current into the gate of the first thyristor. Additional control of converter operation includes, for a fourth period following each second period, turning the first and second transistors off, turning the first thyristor off, and injecting a current into the gate of the second thyristor.

Provided is a battery-charging device that uses a full-bridge rectifier circuit in which each arm is composed of MOSFET as a circuit that rectifies an output of a magnet-type AC generator. The charging device comprises: an ON/OFF state establishment means that, on the basis of a polarity of a potential of each input terminal of the rectifier circuit, establishes ON/OFF state to be assumed by each MOSFET of the rectifier circuit when a battery is charged; a during-charging FET control means that performs control which matches the state of each MOSFET of the rectifier circuit with the state established by the ON/OFF state establishment means when the battery is charged; a short-circuit control means that performs short-circuit control which causes short-circuiting between output terminals of the generator when battery charging is paused; and a FET OFF means that generates a FET OFF time period in which all of the MOSFETs of the rectifier circuit assume an OFF state in a fixed cycle. While short-circuit control is being performed as well, information for establishing the states to be assumed by the MOSFETs of the rectifier circuit during battery charging can be obtained during the FET OFF time periods.

A high-frequency isolation alternating/direct current conversion circuit and a control method thereof are disclosed. The conversion circuit includes an alternating current source, a direct current source, a resonant capacitor, a high-voltage energy-storage filter, a high-frequency inverter bridge, a drive circuit, a resonant inductor, a high-frequency isolation transformer, a direct current side synchronous switch, a control circuit, and the like. The conversion circuit is made to be switched between two working modes, a rectification mode and an inversion mode by using a preset direct current source reference voltage as a reference, according to an external voltage reference, and by using different turn-on working modes of the high-frequency inverter bridge.

A rectifying bridge has a thyristor coupled in series with a rectifying element between a first rectified output terminal of a rectifying bridge circuit and a second rectified output terminal of the rectifying bridge circuit. A diode is coupled in series with a DC voltage source between a gate of the thyristor and the second rectified output terminal.

The power supply is capable of operating in a first state and a second state having a consumption power lower than a consumption power of the first state. The power supply controls a first power supply in the first state such that a first DC voltage is a first voltage and controls the first power supply in the second state such that the first DC voltage is a second voltage lower than the first voltage.

This power conversion device converts AC power to DC power and is provided with: a rectifier unit including a thyristor; a capacitor provided at a stage subsequent to the rectifier unit; and a control unit for controlling the firing of the thyristor. The control unit fires the thyristor after a predetermined time from when a zero-cross point where the voltage of the AC power is zero has been reached, thereby supplying power to the capacitor, said predetermined time being determined in accordance with a predetermined frequency of the AC power. The control unit also sets the predetermined time short every time when firing the thyristor and, when the frequency of the AC power has deviated from the predetermined frequency, performs control so as not to fire the thyristor after the predetermined time determined in accordance with the predetermined frequency.

The present description concerns a circuit for converting from a first alternating voltage to a second voltage. The circuit includes: a first thyristor; a first control circuit of the first thyristor; a power factor correction circuit comprising a coil; and a first circuit configured to convert a third voltage into a fourth DC voltage. The third voltage corresponds to a difference between a potential at a first node connected to an output node of the coil and a reference potential. The fourth DC voltage is configured to supply the first control circuit of the first thyristor, and is referenced with respect to the same reference potential as the third voltage.

In the field of line commutated converters, for use in high voltage direct current (HVDC) power transmission, a line commutated converter comprises a plurality of converter limbs that extend between first and second DC terminals. Each converter limb includes first and second limb portions which are separated by an AC terminal. The first limb portions together define a first limb portion group and the second limb portions together define a second limb portion group. Each limb portion includes at least one switching element that is configured to turn on and conduct current when it is forward biased and it receives a turn on signal and to naturally turn off and no longer conduct current when it is reverse biased and the current flowing through it falls to zero. The converter also includes a control unit.

An AC-DC conversion device that includes a major circuit portion and a control circuit. The major circuit portion includes a converter in which multiple switch portions in a bridge connection include separately-excited switching elements and snubber circuits connected in parallel with the switching elements; and the major circuit portion is connected to an alternating current power supply and a direct current circuit and applies, to the direct current circuit, an alternating current voltage applied from the alternating current power supply by an ON of the multiple switch portions. The control circuit controls the voltage applied to the direct current circuit by controlling the ON timing of the multiple switch portions by inputting a control pulse to each of the multiple switch portions.