磁力悬浮式井下发电装置的优化设计

Optimization Design of Downhole Magnetic Suspension Generator

为解决井下工具长期运行的供电问题,设计了一种小型磁力悬浮式井下发电装置,通过磁力悬浮结构实现叶轮单元的无接触扶正,避免了摩擦带来的启动和效率问题。考虑到结构参数与工作参数对装置发电能力的影响,采用正交设计试验法对该装置进行了组合优化设计,对不同组合参数的装置进行模拟仿真。研究结果表明:发电功率影响因素的重要程度依次为入口速度、扭转力矩、叶片角度、叶片数和叶片高度;在10 m^(3)/d流量工况下,内径34 mm的磁力悬浮式井下发电装置的最优结构为叶轮叶片数16,叶片高3 mm,叶片角度45°;在10 m^(3)/d流量工况下,随着扭转力矩的增大,发电功率呈现先增加后减小的变化趋势,最优扭转力矩为0.003 N·m^(3)优化后的磁力悬浮式井下发电装置试验功率可达0.332 W,使用36 min可充满容量为1200 mAh的5 V锂电池,充电完成后可为工作电流不高于20 mA的用电工具持续供电60 min以上。研究结果可为解决井下工具供电问题提供参考。

A small impeller generator supported by magnetic suspension is designed to solve the power supply problem of long-term operating downhole tools.The magnetic suspension structure realizes contactless centralization of impellers,which avoid the problems in start-up and efficiency due to frictions.Considering the influence of structural parameters and working parameters on the power generation capacity,the orthogonal design test method was used to perform combined optimization design.The generator was simulated with different combinations of parameters.The results show that the importance of the factors influencing the power generation is in order of inlet velocity,torsional moment,blade angle,blade number and blade height.At the flow rate of 10 m^(3)/d,the optimal structure of magnetic suspension impeller generator with inner diameter of 34 mm is as follows:the number of impeller blades is 16,the blade height is 3 mm,and the blade angle is 45°.At the flow rate of 10 m^(3)/d,with the increase of torsion moment,the power generation increases first and then decreases,and the optimal torsion moment is 0.003 N·m.The test power of the optimized magnetic suspension impeller generator reaches 0.332 W,and a 5 V lithium battery with a capacity of 1200 mAh could be fully charged in 36 minutes.After charging,it could continuously supply power for downhole electric tools with working current no more than 20 mA for more than 60 minutes.The study results provide a reference for solving the power supply problem of downhole tools.