带零电压转换软开关的新型单相单级隔离式Cuk开关电源

摘要

针对Cuk变换器在硬开关工作模式下开关损耗大、传输效率低、di/dt和du/dt较大以及电磁干扰严重等不足，研究了一种基于零电压转换（ZVT）软开关技术的隔离式Cuk变换器系统。详细分析了隔离式Cuk变换器的软开关工作过程，计算了变换器和ZVT软开关电路的参数，研制了一台额定输出功率为500W 的带 ZVT 软开关的新型单相单级隔离式 Cuk 高频开关电源样机。实验结果表明：变换器中的开关管均工作于软开关模式，与硬开关工作模式相比，有效减少了开关损耗，减小了 di/dt 和 du/dt，降低了电磁干扰，提高了开关变换器的效率，从而验证了本文提出的方法和参数设计的合理性。%of the Cuk converter has some disadvantages under hard-switching operations, such as high switch losses, low efficiency of conversion, and large electromagnetic interference (EMI), and so on. A new ZVT isolated Cuk converter system is proposed in this paper. The operation modes and parameters design procedure are given as well. A prototype of 500W is built and tested. The experimental results show that all switches can operate in soft-switching mode. Compared with the converter under hard-switching operations, the peak current and peak voltage decrease obviously, while the efficiency of the proposed Cuk converter is improved significantly, which validate that the proposed methods and parameters calculation are reasonable.