Sanken Electric Co., Ltd.

Shimane University

Nagoya University

National University Corporation Shimane University

Hideharu Takano

Hideki Asuke

Masayoshi Yamamoto

Mamoru Tsuruya

Shigeyuki Funabiki

Takahiro Kawashima

Masaki Kanazawa

Hiromitsu Terui

Masashi Ochiai

Hiroyuki Horii

Hirotaka Hara

Jun Imaoka

A bidirectional DC-DC converter includes a series circuit of a first winding of a first reactor, a second reactor, and a first switch connected to both ends of a first DC power source, a series circuit of a second switch and a second DC power source connected to both ends of the first switch, a series circuit of a second winding of the first reactor, a third reactor, a first selector switch, and a first diode connected to both ends of a series circuit of the second reactor and the first switch, a series circuit of a second selector switch, a second diode, and the second DC power source connected to both ends of a series circuit of the first selector switch and first diode, and a controller turning on/off the switches and the selector switches.

Bidirectional DC-DC converter

The present invention includes: a main switch Trconnected to two ends of a DC power supply Vi via a first primary windingand a second primary winding, connected to the first primary winding in series, of a transformer T; a series circuit connected to the two ends of the main switch, and including a reactor L, a diode D, a smoothing capacitor Co and a hoist windingconnected to the second primary winding in series; a series circuit connected to the two ends of the main switch, and including a diode D, a diode Dand the smoothing capacitor; a control circuitto turn on and off the main switch; a soft-switching circuit Da, Tra, La, Cato cause the main switch to perform a soft-switching operation each time the main switch turns on; and a switching control circuitto switch the soft-switching circuit between operating and non-operating modes in accordance with the state of a load.

DC-DC converter

In order to achieve an object to reduce a surge voltage and suppress noise generation, the present invention provides a DC-DC converter with a snubber circuit, which boosts a voltage Vi of a DC power supply. The snubber circuit includes: a series circuit connected to both ends of a smoothing capacitor Co and including a snubber capacitor Cs and a snubber resistor Rs; a snubber diode Dsconnected to a node at which the snubber capacitor Cs and the snubber resistor Rs are connected, and to a node at which a reactor Lrand an additional windingof a transformer Tare connected; and a snubber diode Dsconnected to the node at which the snubber capacitor Cs and the snubber resistor Rs are connected, and to a node at which a reactor Lrand an additional windingof a transformer Tare connected.

DC-DC converter with snubber circuit

A resonant power conversion apparatus includes a transformer Thaving a primary winding n, a secondary winding n, a tertiary winding n, and a reset winding nR, a series circuit of switches Sand S, a capacitor Crand diode Dto the switch S, a capacitor Crand diode Dto the switch S, a series circuit of the winding nand a diode Dn, a series circuit of the winding nR and a diode DR, a reactor Lr connected between a connection point of the switches Sand Sand a connection point of the windings nand n, a switch Sconnected between the DC power source and the winding n, a switch Sconnected between the DC power source and the winding n, and a controllerconfigured to perform a zero-voltage switching operation of the switches Sand S

Resonant power conversion apparatus

The present invention provides a DC-DC converter including a first series circuit connected to both ends of a first switch and formed of a winding of a first transformer, a first reactor, a first diode, and a smoothing capacitor, a second diode connected to a connection point of a primary winding of the first transformer, the winding of the first transformer and the first switch, and to one end of the smoothing capacitor, a second series circuit connected to both ends of a second switch and formed of a winding of a second transformer, a second reactor, a third diode, and the smoothing capacitor, a fourth diode connected to a connection point of a primary winding of the second transformer, the winding of the second transformer and the second switch, and to the one end of the smoothing capacitor, a third reactor connected to both ends of a series circuit of a secondary winding of the first transformer and a secondary winding of the second transformer, and a control circuit which alternately turns on the first switch and the second switch every &#xbd; cycle, turns off the first switch during an on-period of the second switch, and turns off the second switch during an on-period of the first switch.

A current-mode controlled DC-DC converter includes a comparator comparing a first or second current detection signal with a first or second reference current that is based on an error voltage of a voltage detection signal, a pulse generator generating a first pulse signal whose ON time is longer than an interval between when the second current detection signal reaches a minimum value and when the second current detection signal reaches the second reference current, a pulse generator generating a second pulse signal whose ON time is longer than an interval between when the first current detection signal reaches a minimum value and when the first current detection signal reaches the first reference current, the second pulse signal being behind the first pulse signal by a half period, and a PWM circuit generating a first or second PWM signal according to the pulse signal and an output signal from the comparator, thereby turning on/off a switch.

Current-mode controlled DC-DC converter

A bi-directional DC-DC converter includes a first series circuit connected to ends of a first DC power source and including a first winding of a first reactor and a first switch; a second series circuit connected to ends of the first switch and including a second winding of the first reactor, a second reactor, a second switch, a third switch, and a second DC power source; a third series circuit connected to the ends of the first switch and including a fourth switch and the second DC power source; and a control circuit configured to turn on/off the switches and thereby carry out step-up and step-down operations between the first and second DC power sources.

Growing community of inventors

Niiza, Japan

Hideharu Takano