HT-1旋转式井壁取心仪通信原理及干扰抑制

Communication principle and interference suppression of HT-1 rotary sidewall coring tool

HT-1旋转式井壁取心仪以RS-485通信方式传输命令和数据,通信芯片采用半双工设计的MAX487芯片。出现通信干扰时,HT-1地面控制台上显示的所有遥测信号均随机跳变,且井下电机电源不能接通。通信干扰通常与传输线及通道绝缘、电缆缆芯信号分配方式、阻抗匹配、屏蔽地接触电阻、信号波特率等因素有关。文章介绍了一系列抑制通信干扰的方法和措施。

The command and data of HT-1 rotary sidewall coring tool are transmitted by the RS-485 communication way.The communication chip is MAX487,which is one half-duplex chip.When communication interference appears,all telemetering signals shown on the ground panel of HT-1 jump to change randomly,and the motor power of downhole tools can't be put through.Communication interference of HT-1 system is always relevant to the insulation of deliver line and signal channel,the allotment way of cable and signal,impedance matching,contact resistance of shielding ground,and baud rate,etc.Combining with the operational principle of coring tool,the article introduces a series of ways and precautions to suppress the communication interference of HT-1.