核磁测井仪器直流供电电源的控制研究

Control principle of DC power supply for nuclear magnetic logging instrument

核磁仪器发射RF脉冲时需要大量的能量,仅仅通过地面系统直流电源直接供电是无法完成的,必须经过下井仪组合中的电容短节进行储能,利用电容短节中存储的能量向地层发射RF脉冲,并且利用发射间隔由地面直流电源对电容短节快速充电来来完成。为此,核磁测井除了对地面直流供电电源的输出电压、输出电流及程控反应速度有很高要求外,还要求直流电源控制系统必须具备“BOOST”功能,即在给核磁电容短节充电时,能够自动抬升地面直流电源的输出电压,实现对电容短节的快速充电,在电容充电到600Vdc或核磁停止发射时,自动将直流电源的输出电压降回到600Vdc,防止电容和发射模块超过工作电压被击穿。本文详细的介绍了直流电源“BOOST”功能控制机理。

nuclear magnetic instrument emission RF pulse need a lot of energy,only through the ground system dc power supply is unable to complete,must go through the well combination of capacitor short energy storage,using the capacitor short energy storage to stratum RF pulse,and use the emission interval by the ground dc power supply to capacitor short quick charging to complete.For this purpose,the magnetic well in addition to the ground DC power output voltage,output current and programming control reaction speed has high requirements,also requires the DC power control system must have the"BOOST"function,namely can automatically,the output voltage of the ground DC power supply,realize the quick charging of the capacitor,in the capacitor charging to 600 Vdc or nuclear stop transmitting,the output voltage of the DC power automatically back to 600 Vdc,prevent the capacitor and transmission module over the working voltage breakdown.This paper introduces the function control mechanism of BOOST of DC power supply in detail.