水膜压力监测节点旋转非接触供电耦合机理研究

Research on coupling mechanism of rotating contactless power supply coupler for water film pressure wireless monitoring node

水润滑轴承水膜压力无线监测方法中,由于节点随主轴旋转,其供电成为一大难题。而常见的电池、滑环和自供电等供电方法均无法保证无线监测节点的持续和稳定性,因此,提出一种非接触供电方法并深入研究耦合机构电磁耦合机理。首先,通过耦合机构磁通路径建立等效磁路模型,获得了物理模型与电感参数的映射关系。然后,结合有限元仿真分析了耦合机构中磁芯数量、气隙、径向偏移和旋转等因素对耦合性能的影响,并对两侧电路进行无功补偿,通过联合仿真对比了补偿前后的输出功率。最后,将耦合机构安装在水润滑轴承试验台上进行了动态测试试验。研究结果表明,仿真与试验一致性较好,该耦合机构在5 mm气隙下能够兼顾耦合和抗偏移性能,且不受旋转工况影响,经过补偿后的耦合机构平均输出功率为12.496 W,传输效率为71.96%,满足无线监测节点需要。

Due to wireless monitoring node rotates with shaft to monitor the film pressure of water-lubricated bearing,the power supply for wireless node is difficult.The continuity with stability of wireless monitoring node cannot be realized by common power supply methods,such as battery-powered,slipring-powered,self-powered,etc.For this reason,a contactless power supply method is proposed,and the coupling mechanism of coupler is studied.First,in order to obtain the relationship between coupler and electrical parameters,the equivalent magnetic circuit model of coupler was established by magnetic flux path.Second,the influence of core numbers,gap length,radial offset,and rotation to coupling performance were analyzed by FEA,the capacitor is used to compensate the coupler circuit,and the output power before and after compensation was compared by co-simulation.Finally,the coupler was installed on water-lubricated bearing test-rig,and the dynamic test was conducted.The research results show that the simulation and test have favorable consistency,the coupler has well coupled and offset resistance performances when the gap length is 5 mm,meanwhile,it is not affected by rotation condition.After compensation,the average output power of coupler is 12.496 W with a transmission efficiency of 71.96%,which can meet the needs of wireless monitoring node.