论文部分内容阅读
开关电源工作在高频开关状态下,是电子设备主要的电磁干扰源。从麦克斯韦方程出发,分析了开关电源产生电磁干扰(EMI)的主要原因。介绍了开关电源传统的驱动电路及解决EMI的方法,提出了一种结构新颖的驱动电路。该电路不仅具有功率管开启时间不随其输入电容变化的优点,而且采用两段式的方法关闭功率管,有效减缓了di/dt和dv/dt,同时,保证系统具有较高的工作效率。实验结果表明,提出的驱动电路在无效率损失的情况下,经EN55022Class B标准测试,将水平1m的峰值裕度提高15.40dB,垂直3m的峰值裕度提高16.19dB。
Switching power supply work in the high-frequency switch state, is the main source of electromagnetic interference of electronic equipment. Starting from the Maxwell equation, the main reason for the electromagnetic interference (EMI) of the switching power supply is analyzed. The traditional driving circuit of switching power supply and the method of solving EMI are introduced. A novel driving circuit is proposed. The circuit not only has the advantages of power tube open time does not vary with the input capacitance, but also uses two-stage method to turn off the power tube, effectively reducing the di / dt and dv / dt, while ensuring system with high efficiency. The experimental results show that the proposed driver circuit can improve the peak margin of level 1m by 15.40dB and the peak margin of vertical level 3m by 16.19dB after the loss of efficiency and EN55022 Class B standard test.