Digital soft start method of full-bridge LLC converter

A soft-start, converter technology, applied in the direction of output power conversion devices, electrical components, etc., can solve the problem of inability to effectively limit inrush current, and achieve the purpose of reducing inrush current and voltage stress, and reducing inrush current. Effect

Inactive Publication Date: 2016-07-13
GUANGDONG UNIV OF TECH
View PDF3 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At the same time, using this soft start method cannot effectively limit the inrush current within a certain range

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
  • Digital soft start method of full-bridge LLC converter
  • Digital soft start method of full-bridge LLC converter
  • Digital soft start method of full-bridge LLC converter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0031] like figure 1 , figure 2 As shown, the present invention is a digital soft-start method for a full-bridge LLC converter, which is divided into three steps.

[0032] First, set the upper limit of the resonant inductor current I for initial soft start rh (attached figure 2shown in ①) and the lower limit-I rl (attached figure 2 shown in ②). When the bus voltage V in For the rated range, applying a drive pulse requires I rh rl . Then according to the design parameters of the circuit, the switching time of each switching tube is accurately calculated by solving the differential equation. The formula is given as follows:

[0033] Q 1 , Q 2 , Q 3 , Q 4 Opening time calculation formula (Q 1 , Q 4 Simultaneously turn on and turn off; Q 2 , Q 3 Simultaneous turn-on and turn-off):

[0034] u c r = ( U c r - ...

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 digital soft start method of a full-bridge LLC converter. The method includes the steps of: S1. setting a resonant inductive current upper limit I<rh> and lower limit I<rl> for an initial soft start, and accurately limiting surge current within a range in which a circuit stably works; S2. according to design parameters of the circuit, by solving a differential equation, accurately calculating the switching time of each switching tube; S3. keeping switching frequency f1 unchanged till an output voltage can reach a stable value Vo1 at the switching frequency; and S4. in a fixed time interval, continuously decreasing from the switching frequency of f1 till the output voltage reaches a rated output voltage Vo, or when f1 is smaller than resonant frequency fr, ending a soft start. The digital soft start method performs optimized design of a soft start process, according to the design parameters of the circuit, sets the upper limit and lower limit of a resonant network current, accurately calculates the switching time of each switching tube through the differential equation, and then uses a digital control table look-up method to strictly control the whole soft start process.

Description

technical field [0001] The invention relates to the research field of electronic power and electric drive, in particular to a digital soft start method for a full-bridge LLC converter. Background technique [0002] With the rapid development of power electronics technology, more high frequency, high efficiency, high power density and low noise requirements are put forward for switching power supply. At present, the relatively mature soft switching technology, such as phase-shifted full bridge, is difficult to achieve a truly ideal soft switching (including the main switching tube and the secondary rectifying diode), and as the switching frequency increases, its loss continues to increase , so seeking a more efficient, high switching frequency and high power density topology has become the focus of current research. LLC resonant full-bridge converter, as one of the more outstanding performances in the full-bridge topology, has the following advantages: the primary MOSFET ZVS...

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): H02M1/36
CPCH02M1/36H02M1/0012
Inventor 李志忠兰尚荣李学易李优新刘东峰程昱黄国宏
Owner GUANGDONG UNIV OF TECH
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap