Tdk Corporation

Hisanori Cho

Masahiko Hirokawa

Yasuhiro Murai

Akinori Hariya

A power conversion apparatus includes: a first power terminal; a switching circuit including a first switching device on a path coupling a first power node to a first node, a second switching device on a path coupling the first node to a second power node, a third switching device on a path coupling the first power node to a second node, and a fourth switching device on a path coupling the second node to the second power node; a transformer including a first winding coupled to the switching circuit and a second winding; a rectifier circuit; a second power terminal; and a controller that controls operations of the switching circuit and the rectifier circuit to supply power from the second power terminal toward the first power terminal during a predetermined period different from a period during which power is supplied from the first power terminal toward the second power terminal.

Power conversion apparatus and power conversion system

A switching power supply device includes a pair of input terminals, a pair of output terminals, N number (N: an integer of 2 or greater) of transformers, N number of inverter circuits, a rectifying and smoothing circuit, and a driver. The transformers include respective primary-side windings and respective secondary-side windings. The inverter circuits are disposed in parallel between the pair of input terminals and the primary-side windings and each include switching elements. The rectifying and smoothing circuit is disposed between the pair of output terminals and the secondary-side windings and includes a rectifying circuit and a smoothing circuit. The driver sets an input voltage to be supplied to the smoothing circuit at successive stage levels (N+1) by causing, through switching driving, the inverter circuits to apply a predetermined pulse voltage or a voltage at a predetermined voltage value to the respective primary-side windings.

Switching power supply device

A switching power supply unit capable of adjusting the inductance value of a resonance circuit and outputting a rated output voltage regardless of any fluctuation in an input voltage and a load. The switching power supply unit comprises first to fourth switching elements connected with each other in a bridge connection. A diode having a reverse polarity and a capacitor are disposed between main electrodes of each of the switching elements. A first winding of a transformer is connected between first and second connection points An inductor is inserted into a path ranging from the first connection point through the first winding to the second connection point and forms a resonance circuit in conjunction with the capacitors The inductance value L2 of the inductor is arranged to provide the output voltage Vout of an output circuit greater than or equal to the rated output voltage Vout (nom), in a minimum input voltage Vin (mm), a maximum output current Iout (max), and a switching phase-difference f of zero.

Growing community of inventors

Tokyo, Japan

Hisanori Cho