Analysis And Design Of Downhole Wireless Charging Device

Petroleum is an indispensable resource of modern society,and the conflicts between layers in reservoir are deepened by years of exploitation.Layered production can alleviate this conflicts,in which the downhole intelligent valve controller is easier to control than the traditional packer.Nevertheless,the valve controller needs multiple actions to switch the exploitation layer,which quickly consumes its battery energy,so that the battery needs to be replaced regularly.Downhole wireless charging technology is presented to provide power for the switching control of downhole valves.Based on the mechanism of wireless power transmission(WPT)system,the analysis and design of downhole wireless charging device are investigated.It consists of the mathematical derivation of the system and simulation by virtue of the multiphysics simulation software.The influence of various device parameters on the coil electrical parameters and mutual inductance is researched.Furthermore,the rationality of analysis and design is verified by experiments.The main research contents are as follows:First,the condition for efficient transmission of the system at a rated load power is analyzed by dint of equivalent coupling model,the corresponding matched load and the condition formula of high efficiency at rated power are obtained.Second,the simulation is guided by the theoretical analysis,and the relationship between device parameters and system is studied.After optimization,a downhole WPT system with high transmission efficiency at a rated 50 W power is built.Finally,the inverter and rectifier circuit are researched and designed.The physical model is basically consistent with the theory and simulation ideas by testing the circuit and overall device prototype,the feasibility of analysis and design of device is verified.