一种高效率高增益的谐振型直流功率变换器

A Novel High-efficiency High Step-up Resonant DC/DC Converter

提出一种高效率高增益的谐振型直流功率变换器。该电路利用耦合电感、开关电容电路及输出串联结构实现高电压增益。耦合电感中的漏感能量由输出端回收,利于提升效率,降低开关管的电压应力。同时借助漏感和开关电容谐振,次级二极管的零电流开关得以实现,从而减小反向恢复的影响。详细分析了高效率高增益谐振型直流功率变换器的工作原理,及连续导通模式下变换器的稳态性能,并借助一台35 V输入、200 V/0.75 A输出的实验样机验证了理论分析的正确性。

A novel high-efficiency high step-up resonant DC/DC converter is proposed.Through coupled inductor, switched-capacitor circuit and output series structure, the proposed converter achieves high step-up voltage gain with- out large duty cycle.The energy stored in the leakage inductance of the coupled inductor can be recycled to the out-put terminal, which not only improves efficiency but also alleviates large voltage spike to reduce the voltage stress.Ad- ditionally, the secondary diodes can achieve zero current switching by the resonant tank consists of the leakage in- ductor and switched-capacitors, which can eliminate the reverse recovery problem and reduce their switching loss sig- nificantly.The operating principles and steady-state analyses of the proposed converter in continuous-conduction mode are discussed in detail.Finally,a prototype sample with 35 V input and 200 V/0.75 A output is implemented and the experimental results verify the correction of the theoretical analysis.