JPH0354379U

JPH0354379U -

Info

Publication number: JPH0354379U
Application number: JP7802990U
Authority: JP
Priority date: 1990-07-23
Filing date: 1990-07-23
Publication date: 1991-05-27
Also published as: JPH0353597Y2

Description

[Brief explanation of drawings]

第１図は従来回路の説明図、第２図はその動作
説明図の波形図、第３図は本考案の一実施例回路
図、第４図はその動作説明用の波形図である。ＰＷ１……入力直流電源、ＡＣ……商用周波交
流電源、ＦＲ１……全波整流回路、Ｃ１……入力
用コンデンサ、ＰＷ２……駆動回路用補助直流電
源、ＣＯＮＶ……ＤＣ−ＤＣコンバータ、Ｃ２…
…入力用コンデンサ、７……出力用主変圧器、８
……１次巻線、９……２次巻線、１０，１１……
ダイオード、１２……チヨーク、１３……コンデ
ンサ、ＲＬ……負荷、３……駆動用電流トランス
、４……１次巻線、５……ベース巻線、６……制
御巻線、ＣＯＮ……制御回路、２……駆動用トラ
ンジスタ、ＰＣ……不足電圧保護回路、ＤＶ……
不足電圧検出回路、Ｒ１，Ｒ３，Ｒ４……抵抗、
ＣＺ１……主電圧ダイオード、Ｑ１……不足電圧
検出用トランジスタ、ＳＳＳ……駆動用トランジ
スタ短絡回路、Ｑ２……短絡用トランジスタ、Ｒ
２……抵抗、Ｄ１……ダイオード。 FIG. 1 is an explanatory diagram of a conventional circuit, FIG. 2 is a waveform diagram illustrating its operation, FIG. 3 is a circuit diagram of an embodiment of the present invention, and FIG. 4 is a waveform diagram illustrating its operation. PW1...Input DC power supply, AC...Commercial frequency AC power supply, FR1...Full wave rectifier circuit, C1...Input capacitor, PW2...Auxiliary DC power supply for drive circuit, CONV...DC-DC converter, C2...
...Input capacitor, 7...Output main transformer, 8
...Primary winding, 9...Secondary winding, 10, 11...
Diode, 12...Chiyoke, 13...Capacitor, RL...Load, 3...Drive current transformer, 4...Primary winding, 5...Base winding, 6...Control winding, CON... Control circuit, 2... Drive transistor, PC... Undervoltage protection circuit, DV...
Undervoltage detection circuit, R1, R3, R4...resistance,
CZ1...Main voltage diode, Q1...Transistor for undervoltage detection, SSS...Drive transistor short circuit, Q2...Short circuit transistor, R
2...Resistor, D1...Diode.

Claims

[Claims for Utility Model Registration] Control that is operated by a predetermined output of an auxiliary DC power supply for a drive circuit operated by an input DC power supply, and sends an on/off signal corresponding to a comparative difference output between an output voltage and a reference voltage for setting the output voltage. a driving semiconductor switching element that is controlled on and off by circuit output;
A series circuit is provided between a primary winding of an output main transformer connected to the input DC power supply, a primary winding of a drive current transformer, and a collector-emitter of a conversion main transistor, and the drive semiconductor switching When the element is turned on, current is caused to flow through a control winding provided in the drive current transformer, and a reverse bias current is applied to the conversion main transistor through the base winding of the drive current transformer to turn the element off; When the driving semiconductor switching element is turned off, a base current is caused to flow through the base winding of the driving current transformer by transformer action using the excitation energy accumulated in the driving current transformer during the ON period of the driving semiconductor switching element. In a DC-DC converter that turns on the conversion main transistor, rectifies and smoothes the secondary winding voltage of the output main transformer sent by the on/off operation of the conversion main transistor, and supplies power to a load. , a second control winding is provided in the drive current transformer, and an undervoltage detection circuit that detects a drop in the output voltage of the input DC power supply; A DC-DC converter comprising: a reverse bias current supply circuit including a reverse bias current supply semiconductor switching element connected in series with the second control winding of the input DC power source and between the output terminals of the input DC power supply. converter.