兰州理工大学学报

兰州理工大学学报 ›› 2022, Vol. 48 ›› Issue (5): 79-84.

• 自动化技术与计算机技术 • 上一篇    下一篇

一种原边反馈反激式数字化LED驱动电路

刘芳*1, 王群杰1, 白倩2   

  1. 1.北方民族大学 电气信息工程学院, 宁夏 银川 750021;
    2.黄河交通学院 智能工程学院, 河南 焦作 454000
  • 收稿日期:2021-04-21 出版日期:2022-10-28 发布日期:2022-11-21
  • 通讯作者: 刘 芳(1970-),女,宁夏中卫人,教授,博导. Email:fangliu214@163.com
  • 基金资助:
    宁夏自然科学基金(2021AAC03229),大型电气传动系统与装备技术国家重点实验室开放基金(SKLLDJ022019006),宁夏高等学校一流学科建设(电子科学与技术学科)资助项目(NXYLXK2017A07)

A digital LED driving circuit with the primary side feedback control flyback converter

LIU Fang1, WANG Qun-jie1, BAI Qian2   

  1. 1. College of Electrical Information Engineering, North Minzu University, Yinchuan 750021, China;
    2. College of Intelligent Engineering, Huanghe Jiaotong University, Jiaozuo 454000, China
  • Received:2021-04-21 Online:2022-10-28 Published:2022-11-21

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摘要： 为了减少LED的频闪现象,设计了一款原边反馈反激式数字化恒流控制驱动电路.推导了该电路的软启动/恒流切换依据,给出了恒流控制原理,构建了数字控制器的内部结构.软启动/恒流切换模块的设置可以有效抑制浪涌电流,确保Flyback变换器平稳进入恒流状态;基于恒流控制原理设计了去磁时间采样及计数器调制模块,与控制信号生成模块协同工作,达到了自动调节开关导通信号的目的.采用ModelSim与Simulink软件联合仿真,验证了设计方案的可行性.结果表明,Flyback变换器运行在恒流状态时去磁时间与开关周期的比值恒定,输出恒流约为320 mA,电流纹波0.38%,驱动电路可以稳定可靠地工作.

关键词: 数字控制, LED驱动, 反激变换器, 恒流输出, 联合仿真

Abstract: In order to reduce flickering of the LED, a driving circuit with the primary side feedback control flyback converter is specifically designed on the basis of the digital technology. The principle of soft-start and the controlling flow of constant current output is deduced, the constant current control principle is given, and the internal structure of the digital controller is constructed. The setting of soft-start/constant current switching module can effectively suppress the surge current of the flyback converter and ensure that the flyback converter enters the constant current state smoothly. Based on the principle of constant current control, the demagnetization time sampling module and counter modulation module are designed, which works in coordination with the control signal generation module to automatically switching signal. Finally, the feasibility of the presented scheme is verified by the united simulation technique based on ModelSim and Simulink. The results show that the ratio of demagnetization time to switching period is constant when the flyback converter operates in constant current state, with the output constant current of about 320 mA and the current ripple of 0.38%. Consequently, the drive circuit investigated in this paper can work stably and reliably.

Key words: digital control, LED driver, flyback converter, constant current output, united simulation

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