Discontinuous conduction mode is often used in boost power factor correction converter. This article proposes a unified control method to achieve both pulsewidth modulation control and pulse frequency modulation control, which is based on the virtual impedance principle. The control modes can easily be changed by only adjusting one control parameter. Consequently, by comprehensively considering current ripple, switching frequency, and efficiency, the converter can operate flexibly in the situation of variable loads. This article first introduces the operation principle of the proposed unified control method. Then, the operation condition for each control mode is discussed. Besides, the current ripple, the switching frequency, and the power loss are analyzed. Finally, the experimental results of steady-state test and load switching test are presented. And the efficiency of the converter is more than 95% in the range from half load to full load. These experimental results fully verify the effectiveness of the proposed control.

中文翻译：

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具有 PWM/PFM 模式无缝转换的 PFC 转换器统一控制


间断导通模式常用于升压功率因数校正转换器。本文提出一种基于虚拟阻抗原理的统一控制方法，实现脉宽调制控制和脉频调制控制。只需调整一个控制参数即可轻松改变控制模式。因此，通过综合考虑电流纹波、开关频率和效率，转换器可以在可变负载的情况下灵活运行。本文首先介绍了所提出的统一控制方法的工作原理。然后，讨论每种控制模式的操作条件。此外，还分析了电流纹波、开关频率和功率损耗。最后给出了稳态测试和负载切换测试的实验结果。转换器的效率在半载到满载范围内均超过95%。这些实验结果充分验证了所提出的控制的有效性。