This article proposes a unified pulsewidth-cycle (UPWC) control strategy to achieve mixed-mode operation and consistent valley switching (VS) for boost power factor correction converter. Compared with conventional single-mode controllers, it has a unified scheme to achieve single discontinuous conduction mode (DCM), single critical conduction mode (CRM), or mixed DCM/CRM operations in each half-line cycle. To regulate the input current as a sinusoid, the UPWC controller adopts a variable pulsewidth and a near-constant switching cycle under DCM, while adopts a constant pulsewidth and a variable switching cycle under CRM. To facilitate analysis, normalized mapping of operation modes is provided, along with the final pulsewidth and switching cycle. Furthermore, to ensure consistent VS, a controlled zero current detection method is proposed to fix the turn-on point of the power switch. No matter in DCM or CRM, consistent VS reduces both the switching loss and current distortion caused by parasitic resonance. To further reduce the current distortion caused by fixing the turn-on point, a compensation gain is provided that reshapes the input current as a sinusoid. Finally, through mixed DCM/CRM operation and consistent VS, the proposed UPWC controller achieves preferable performances in the power range, efficiency, power factor, and current distortion.

中文翻译：

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统一脉宽周期控制策略可实现升压 PFC 转换器的混合 DCM/CRM 操作和一致谷底开关


本文提出了一种统一的脉宽周期 (UPWC) 控制策略，以实现升压功率因数校正转换器的混合模式操作和一致的谷底开关 (VS)。与传统的单模控制器相比，它具有统一的方案，可以在每个半线周期内实现单一不连续导通模式（DCM）、单一临界导通模式（CRM）或混合DCM/CRM操作。为了将输入电流调节为正弦波，UPWC控制器在DCM下采用可变脉冲宽度和接近恒定的开关周期，而在CRM下采用恒定脉冲宽度和可变开关周期。为了便于分析，提供了操作模式的归一化映射以及最终脉冲宽度和开关周期。此外，为了确保一致的VS，提出了一种受控零电流检测方法来固定功率开关的导通点。无论在DCM还是CRM中，一致的VS都可以减少寄生谐振引起的开关损耗和电流失真。为了进一步减少因固定导通点而引起的电流失真，提供了补偿增益，将输入电流重塑为正弦曲线。最后，通过混合 DCM/CRM 操作和一致的 VS，所提出的 UPWC 控制器在功率范围、效率、功率因数和电流失真方面实现了更好的性能。