基于FPGA+Si8235控制的LLC谐振变换器设计

Design of LLC Resonant Converter Based on FPGA+Si8235

为了增加LLC谐振变换器控制灵活性,降低驱动电路的损耗,提出了基于FPGA控制和Si8235驱动的方案;分析了LLC谐振变换器的增益特性;对载波调制隔离驱动芯片Si8235的开通和关断时间进行了测试比较,设计加速关断的优化驱动电路;实验证明,LLC谐振变换器使用FPGA+Si8235组合的控制驱动策略,使电路更加简单,能实现更快的驱动速度,提高控制灵活性和增加性能效率。

LLC resonant converter based on FPGA digital control and Si8235 driven is proposed to increase the flexibility and reduce the power loss of the driving circuit. Detailed analysis on gain characteristic of LLC resonant converter is presented. According to the test of the turn on and turn off time of the carrier modulation isolated chip Si8235 and making a comparison between them, an optimal driving circuit with cutting down turn-off time is designed and realized. The experiments show that LLC resonant converter combined with FPGA control and Si8235 driven strategy achieves simpler circuit,faster drive speed,and control flexibility and performance efficiency.