提出一种Boost-LCL谐振变换器,由全桥电路、主/辅助变压器、谐振器件和一组整流桥构成。辅助变压器既是反激变压器,其原边绕组又同时复用作谐振电感和Boost电感以提高功率密度和电压增益。电路依据输出电压需求有低、高2种电压增益工作...提出一种Boost-LCL谐振变换器,由全桥电路、主/辅助变压器、谐振器件和一组整流桥构成。辅助变压器既是反激变压器,其原边绕组又同时复用作谐振电感和Boost电感以提高功率密度和电压增益。电路依据输出电压需求有低、高2种电压增益工作模式。在低电压增益模式,电路工作在定频脉冲宽度调制(pulse width modulation,PWM)模式。在高电压增益模式,电路工作在Boost+调频模式,即在全桥谐振之前加入Boost脉冲频率调制(pulse frequency modulation,PFM)以提高输出电压。与传统LCL谐振变换器相比,新电路在在同样的谐振参数下,具有更高的电压增益,更适合宽输出范围使用。详细分析了新拓扑的工作原理,并与传统拓扑进行了对比分析。研制了一台100～150V输出的样机,测试表明在宽输出范围内,新拓扑效率最高可达93.1%,验证了理论分析的正确性。展开更多
This paper proposes a family of PWM modulation strategies for boostfull-bridge (FB) converters. The modulation strategies can be classified into two kinds according tothe turn-on sequence of the diagonal switches. The...This paper proposes a family of PWM modulation strategies for boostfull-bridge (FB) converters. The modulation strategies can be classified into two kinds according tothe turn-on sequence of the diagonal switches. The concept of leading switches and lagging switchesis introduced to realize soft-switching. According to the soft-switching realized by the leadingswitches and the lagging switches, two kinds of soft-switching techniques for PWM boost FBconverters yield: zero-current-switching (ZCS) and zero-current and zero-voltage-switching (ZCZVS).Simulation results verify the analysis.展开更多
A 5-level PFC （power factor correction） topology with fault-diagnostic and fault-tolerant capability is proposed and compared to known structures. It is derived from a 3-level non differential double-boost PFC inclu...A 5-level PFC （power factor correction） topology with fault-diagnostic and fault-tolerant capability is proposed and compared to known structures. It is derived from a 3-level non differential double-boost PFC including fly-cap cells. The series-connection of the two low-voltage switching-cells is decoupled by a single flying capacitor that provides a direct fault-tolerant capability and a post-failure operation increasing the availability of converter. The monitoring of the voltages across flying capacitors allows a rapid detection and localization either for open circuit failure or short-circuits failure. A PWM （pulse width modulation） phase-disposition type reconfiguration is also used and presented in order to optimize both normal operation and post-fault continuation. The design and the most important features are highlighted thanks to a digital control frame and a mock-up rated to： AC voltage network 115 V-load 400 V-nominal power 4 kW-switching frequency 62 kHz.展开更多
文摘提出一种Boost-LCL谐振变换器,由全桥电路、主/辅助变压器、谐振器件和一组整流桥构成。辅助变压器既是反激变压器,其原边绕组又同时复用作谐振电感和Boost电感以提高功率密度和电压增益。电路依据输出电压需求有低、高2种电压增益工作模式。在低电压增益模式,电路工作在定频脉冲宽度调制(pulse width modulation,PWM)模式。在高电压增益模式,电路工作在Boost+调频模式,即在全桥谐振之前加入Boost脉冲频率调制(pulse frequency modulation,PFM)以提高输出电压。与传统LCL谐振变换器相比,新电路在在同样的谐振参数下,具有更高的电压增益,更适合宽输出范围使用。详细分析了新拓扑的工作原理,并与传统拓扑进行了对比分析。研制了一台100～150V输出的样机,测试表明在宽输出范围内,新拓扑效率最高可达93.1%,验证了理论分析的正确性。
文摘This paper proposes a family of PWM modulation strategies for boostfull-bridge (FB) converters. The modulation strategies can be classified into two kinds according tothe turn-on sequence of the diagonal switches. The concept of leading switches and lagging switchesis introduced to realize soft-switching. According to the soft-switching realized by the leadingswitches and the lagging switches, two kinds of soft-switching techniques for PWM boost FBconverters yield: zero-current-switching (ZCS) and zero-current and zero-voltage-switching (ZCZVS).Simulation results verify the analysis.
文摘A 5-level PFC （power factor correction） topology with fault-diagnostic and fault-tolerant capability is proposed and compared to known structures. It is derived from a 3-level non differential double-boost PFC including fly-cap cells. The series-connection of the two low-voltage switching-cells is decoupled by a single flying capacitor that provides a direct fault-tolerant capability and a post-failure operation increasing the availability of converter. The monitoring of the voltages across flying capacitors allows a rapid detection and localization either for open circuit failure or short-circuits failure. A PWM （pulse width modulation） phase-disposition type reconfiguration is also used and presented in order to optimize both normal operation and post-fault continuation. The design and the most important features are highlighted thanks to a digital control frame and a mock-up rated to： AC voltage network 115 V-load 400 V-nominal power 4 kW-switching frequency 62 kHz.
