Flyback active clamping circuit and control method

A clamping circuit and voltage technology, which is applied in the direction of control/regulation system, electrical components, and adjustment of electrical variables, etc., can solve the problems of no precise control of switching tube MA, no distinction between judgment and control, and increased conduction loss, etc., to achieve reduction Loss, reduction of turn-on loss, effect of reduction of conduction loss

Active Publication Date: 2018-03-02
JOULWATT TECH INC LTD
View PDF5 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] L M is the magnetizing inductance in the primary winding, the prior art utilizes figure 2 The control method in the control method controls the turn-off of the switch tube MA. Since there is no precise control for the turn-off time of the switch tube MA before the main power switch tube M0 is turned on, it may cause L M The technical problem of increasing the conduction loss due to excessive negative current
Moreover, the BCM and DCM modes are different for whether negative current is required, and the prior art does not distinguish, judge and control this

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Flyback active clamping circuit and control method
  • Flyback active clamping circuit and control method
  • Flyback active clamping circuit and control method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0029] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention is not limited to these embodiments. The present invention covers any alternatives, modifications, equivalent methods and schemes made within the spirit and scope of the present invention.

[0030] In order to provide the public with a thorough understanding of the present invention, specific details are set forth in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details.

[0031] In the following paragraphs the invention is described more specifically by way of example with reference to the accompanying drawings. It should be noted that all the drawings are in simplified form and use inaccurate scales, which are only used to facilitate and clearly assist the purpose of illustrating the embodiments of t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a flyback active clamping circuit and a control method. The flyback active clamping circuit comprises a flyback switch power supply, a first capacitor and a first switch tube.One end of the first capacitor is connected to a high potential end of an input power supply, and the other end is connected to a first end of the first switch tube. A second end of the first switch tube is connected to a common end of a main power switch tube and a primary winding. According to time of main power switch tube conduction and turn off of the first switch tube, and a voltage of two ends of a magnetizing inductance, turn off time of the first switch tube is adjusted. In the invention, under a critical conduction mode (BCM) or a discontinuous conduction mode (DCM), the turn off time of the first switch tube is adjusted and controlled, which is good for reducing losses. Especially under the critical conduction mode, a slight negative current is generated on the magnetizing inductance so that discharge is performed on the common end of the main power switch tube and the primary winding (a drain electrode of the main power switch tube) before the main power switch tube is conducted.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a flyback active clamping circuit and a control method thereof. Background technique [0002] A flyback switching power supply is an isolated switching power supply that is widely used in alternating current direct current (AC / DC) and direct current direct current (DC / DC) conversion, and provides insulating isolation between the input stage and the output stage. The flyback switching power supply includes a main power switch tube, a transformer and a secondary rectifier tube, the transformer includes a primary winding and a secondary winding, the main power switch tube is connected to the primary winding, and the secondary rectifier tube It is connected with the secondary winding, and the switching state of the main power switch tube is controlled by the primary side control circuit, and the secondary rectifier tube located on the secondary side conducts freewheeling af...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H02M3/335
CPCH02M3/33569H02M1/0058H02M3/01Y02B70/10H02M1/0054H02M1/08
Inventor 黄必亮周逊伟
Owner JOULWATT TECH INC LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products