【作者】 刘浩洋；

【导师】 汪洋；

【作者基本信息】 哈尔滨工业大学 ， 信息与通信工程， 2019， 硕士

【摘要】 水下无线传感器网络(Underwater Wireless Sensor Networks,UWSNs)在海洋勘探、水文监测、远洋开发等领域具有重要的应用价值。近年来随着水下无线传感器网络的应用场合越来越复杂,传统的以金属线缆方式为传感器供能和回传数据的方法已经不能满足实际需求。无线能量传输(Wireless Power Transfer,WPT)技术和近场通讯(Near Field Communication,NFC)技术由于具有无需收发设备之间的物理接触即可实现能量与信息的传输,且海水不会影响作为能量与信息载体的近场磁场传播的特点。因此本文以等效电路理论和近场电磁场理论为基础,将无线能量传输技术与近场通讯技术相结合,为水下无线传感器网络的供能和数据回传提供了良好的解决方案。针对近场电磁场传播距离受限,使能量与信息收发设备无法保持稳定磁耦合的问题,本文重点研究了能量传输的功率与传输介质、收发间距之间的关系。提出了在收发线圈之间插入铁氧体磁芯来提升收发线圈之间介质的平均磁导率以提高收发间距的方案,并通过仿真计算确定了磁芯参数。同时,深入分析了线圈内部磁场分布,针对收发线圈相对径向偏移的问题,提出了使用铁氧体磁芯的优化方法,仿真分析表明提出的方法可以有效抵御海流扰动引起的径向偏移,提高充电过程的稳定性。针对复杂环境下的UWSNs的数据回传问题,本文提出了一种将传感器端数据回传至自主水下航行器(Autonomous Underwater Vehicle,AUV)保存并带回水面对接站的无线能量与信息同步传输方法。该方法中AUV作为电能的供电端和数据的接收端,UWSNs作为电能的受电端和数据的发送端。将两组空间位置相互正交的线圈分别用于能量和信息传输,实现了能量和信息传输过程的同步和独立化,为传感器供电和数据回传提供了解决方案。针对磁耦合谐振无线能量传输技术对发射和接收线圈的轴线相重合的要求,本文提出了一种AUV姿态控制方法,通过监测AUV上发射线圈的传输指标来确定收发线圈的耦合状态,进而获知发射线圈与接收线圈的角度偏转情况以及AUV的姿态情况。并通过传输特性参数与姿态控制处理器之间的实时反馈来调整AUV姿态,优化了收发线圈的相对角度,从而使传输特性达到最佳状态。更多还原

【Abstract】 Underwater Wireless Sensor Networks(UWSNs)have important application value in marine exploration,hydrological monitoring,and oceanic development.In recent years,with the increasing complexity of the application of UWSNs,the traditional method of powering and returning data by means of metal cable has not been able to meet the actual needs.Wireless Power Transfer(WPT)and Near Field Communication(NFC)enable energy and information transmission without physical contact between transceivers,and seawater does not affect energy and The characteristics of the propagation of the near-field magnetic field of the information carrier.Therefore,based on the equivalent circuit theory and near-field electromagnetic field theory,this paper combines WPT technology with NFC technology to provide a good solution for the energy supply and data back-transmission of UWSNs.Aiming at the limited propagation distance of near-field electromagnetic field,which makes it not convenient to maintain stable magnetic coupling between energy and information transceiver equipment.This paper focuses on the relationship between power transmission energy and transmission medium,transmission and reception spacing.A ferrite core is inserted to increase the average magnetic permeability in seawater to improve the transmission and reception spacing,and the core parameters are determined through simulation calculation.At the same time,the internal magnetic field distribution of the coil is analyzed.For the problem of relative radial offset of the transmitting and receiving coils,an optimization method using ferrite core is proposed.The simulation analysis shows that the proposed method can effectively resist the radial offset caused by current disturbance,which improves the stability of the charging process.Aiming at the problem of data backhaul of UWSNs in complex environment,this paper proposes a wireless energy and information synchronization transmission method that transmits the sensor-side data back to Autonomous Underwater Vehicle(AUV).In this method,AUV is used to supply power and collect data when UWSNs are used to receive power and transfer data,the two sets of coils whose spatial positions are orthogonal to each other are used for energy and information transmission,which realizes the synchronization and independence of energy and information transmission process,which provides a solution for sensor power supply and data backhaul.Aiming at the requirement of the magnetic resonance coupling wireless energy transmission technology to coincide with the axes of the transmitting and receiving coils,this paper proposes an AUV attitude control method.By monitoring the transmitting characteristic parameters of the power supply terminal,the coupling status of the transmitting and receiving coils is determined,and then the relative angle between the transfer coil and the receiving coil and the attitude of the power supply end is obtained.The AUV attitude is adjusted by real-time feedback between the transmitting characteristic parameters and the attitude control processor,and the relative angles of the transmitting and receiving coils are optimized,so that the transmission characteristics are optimized.更多还原