石油测井仪器电流检测系统的研究

摘要

In the process of developing the logging instrument,the power consumption of the instrument should be monitored so that the instrument can be equipped with the proper battery.A detection system which can continuously monitor the small DC current in large dynamic range is designed,for system with weak current components for the continuous monitoring of special requirements,with high input impedance method and differential op amp I/V conversion method to extract signal amplification,multistage hardware filter circuit and digital filter with interference suppression method.The emphasis is to suppress the internal noise of the system and the external power frequency interference.In addition,the software can realize the automatic range conversion to meet the needs of large range current detection.After the experiment verify the system reached the use requirement.%针对测井仪器研发过程中,需要监测仪器的功耗,以便给仪器配置合适电池的需求,设计了一种能够在大动态范围内,连续监测直流小电流的检测系统,针对系统有连续监测微弱电流成分的特殊要求,设计了采用高输入阻抗法与差分运放I/V转换法提取放大信号、多级硬件电路滤波与数字滤波结合的抑制干扰方法,重点是抑制系统内部噪声与系统外部工频干扰;此外采用软件实现自动量程转换以满足大范围电流检测的需求,经实验验证达到使用要求.