倍压整流电路在DC/DC大升压比电路中的应用

Application of Voltage-doubler Rectifier Circuit in High-frequency DC/DC High Boost Ratio Circuit

针对随钻核磁共振测井仪对井下高压电源的设计需求,采用一种半桥形式的倍压整流电路结构,解决了大升压比DC/DC电路中变压器体积及寄生参数的控制问题,同时抛弃传统LC滤波输出,基本消除了整流二极管的高压振铃问题,有利于整流二极管的选型工作。其次,通过变压器漏感和倍压电容的谐振,优化电流波形,进一步减轻整流二极管及开关管的电流应力及功率耗散。最终,通过设计实验室原理样机,验证上述设计的可行性。

Aiming at the design requirements of the underground high-voltage power supply while drilling nuclear magnetic resonance logging(NMRL)tool,a half-bridge voltage doubler rectifier circuit structure was adopted to solve the control problem of transformer volume and parasitic parameters in high-frequency large-boost ratio DC/DC circuit.At the same time,the traditional LC filter output was discarded,which could basically eliminate the high-voltage ringing problem of the rectifier diode,so as to be beneficial to the selection of the diode.Secondly,through the resonance of the leakage inductance of the transformer and the voltage doubler capacitor,the current waveform was optimized to further reduce the current stress and power dissipation of the rectifier diode and the switching transistor.Finally,the feasibility of the above design was verified by designing a laboratory prototype.