一种Boost型PFC电路在DCM下的恒频控制方案

更新时间：2020-05-25 06:23:52 大小：421K 上传用户：IC老兵查看TA发布的资源 标签：PFC电路 下载积分：5分评价赚积分（如何评价?）收藏评论(0) 举报

资料介绍

通过对Boost型变换器在不连续导电模式DCM（Discontinued Conduction Mode）下平均电感电流的分析，得到了在恒频状态下实现功率因数校正PFC（Power Factor Correction）时，功率开关管所需的开启时间与输入、输出电压之间的数学关系，并结合实际电路设计，提出了一种PFC控制方案。该方案利用输入、输出电压的采样信号和一个二次积分电路来调制功率开关管的开启时间，使Boost变换器在不连续导电模式下恒频工作并实现电压跟随。理论分析求解出了电路控制参量取值的边界条件。实验电路测试获得了接近1的功率因数和很低的电流谐波含量。

The average inductor current of a Boost converter operating in Discontinued Conduction Mode （DCM） is analyzed, and the mathematical relationship between the power switch turn-on-time and input-output voltage is found to guarantee that the converter operates with constant switching frequency as a Power Factor Correction （PFC） regulator. Along with a practical circuit design, this paper proposes a PFC control method employing the sampling circuit of input-output voltage and a double integral circuit, with which the Boost converter can operate in DCM with constant switching frequency as a voltage follower. The theoretical analysis works out the boundary conditio...