The Control Technology of Downhole Tools Based on Radio Frequency Identification

In order to overcome the shortcomes of ball injection downhole tools,the working process and the tool structure of a RFID triggering downhole tool were discussed.Fluid mechanics were used to analyze the influence factors of RFID damage and reading efficiency.An antenna matching circuit which could adapt itself to all kinds of drilling fluid environment was designed,and a reader circuit system and related embedded program were developed.The experimental results proved that the reading effect of 125 kHz and 134 kHz low frequency RFID were best and they satisfied the requirements of the downhole Radio Frequency Receiver.In conjunction with the theoretical analysis and the experimental results,the Downhole Radio Frequency Receiver was designed.The coupling efficiency was improved by using long distance antenna matching circuit.The experimental results showed that the reading success rate was 100 % under 3 m/s velocity of mud flow.The research results showed that RFID label instructions designed system could be applied to the control of downhole tools through the optimization of electronic label work frequency and optimal read power antenna matching.