深海无人航行器双向无线充电系统的涡流损耗分析与效率优化  

Analysis of Eddy Current Loss and Efficiency Optimization for Bidirectional Underwater Wireless Power Transfer of AUVs

作　　者：刘宇鑫 高飞[1,2] 刘鑫 程正顺 刘东[1,2] Liu Yuxin;Gao Fei;Liu Xin;Cheng Zhengshun;Liu Dong(School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University,Shanghai 200240 China;School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University,Shanghai 200240 China)

机构地区：[1]上海交通大学电子信息与电气工程学院,上海200240 [2]上海交通大学船舶海洋与建筑工程学院,上海200240

出　　处：《电工技术学报》2024年第18期5599-5609,共11页Transactions of China Electrotechnical Society

基　　金：上海交通大学“深蓝计划”基金项目(SL2022MS009);国家自然科学基金青年科学基金项目(52307012)资助。

摘　　要：无线电能传输(WPT)技术在深海无人航行器(AUUS)领域中应用逐渐广泛,相比于空气介质的无线充电而言,海水介质中无线充电产生的涡流损耗严重降低了能量传输效率。该文提出一种采用一次侧和二次侧移相策略的双边LCC水下WPT系统,降低海水介质中的涡流损耗,提高系统效率。通过研究两线圈电流相位差对海水介质的涡流损耗的影响,建立合成感生电场模型,计算合成感生电场的分布和涡流损耗。在其他条件不变时,增大两线圈电流的相位差,会使线圈间各点处的合成感生电场幅值下降,使涡流损耗在总损耗的占比中下降,提高能量传输效率。通过对比在空气介质和海水介质中的损耗与线圈间电流相位差之间的关系,可以得到海水介质中无线充电时的最大效率点的电流相位差。相比于空气介质而言,在海水介质中无线充电的最大效率点处,线圈间的电流相位差增大。在深海双向双边LCC无线充电系统中,仅需增大两侧逆变电压相位差,即可增大线圈间电流相位差,进而提高系统效率。实验中搭建了200 V/3.5 kW级水下无线充电样机,通过增大两侧逆变器之间相位差,实现了91.5%的最大效率传输,比不采用移相策略时的效率提升了0.8%,证实了理论分析结果的正确性与可行性。Wireless power transfer(WPT)has been widely applied in autonomous underwater vehicles(AUVs),effectively addressing the issues related to limited endurance,challenging plug-and-charge processes,and leakage in seawater.Compared with the WPT in air,the eddy current loss(ECL)in seawater significantly decreases the efficiency.Recently,some methods have been proposed to reduce the effect of ECL,such as modifying coil structures and adjusting operating frequency,which complicates the system design.This paper proposes an underwater bidirectional LCC WPT system with a phase-shifting strategy for the primary and secondary inverters.The ECL is reduced by increasing the phase angles between the inverter voltages on both primary and secondary sides,thereby increasing overall efficiency.With fixed coil parameters,the amplitude of the induced electric field excited by each coil current in seawater is directly proportional to the current amplitude,while the phase angle of the induced electric field at any point between the two coils is almost the same.The synthetic induced electric field is the vector sum of the induced electric field generated by each coil current.Thus,the phase angle of the synthetic-induced electric field is primarily determined by the phase angle of the coil current.Consequently,increasing the phase angle between the coil currents decreases the amplitude of the synthetic-induced electric field,leading to a decrease in ECL and an increase in efficiency.When the system reaches the maximum efficiency,the decrease rate in ECL equals the increase rate in other circuit losses.To achieve zero voltage switching(ZVS)for both side inverters,the phase angle between the two inverter voltages varies from 90°to 180°.A prototype of a 200 V/3.5 kW underwater bidirectional LCC WPT system is built.Waveforms of inverter voltages,inverter currents,and coil currents are shown with phase angles of 100°and 120°.Increasing the phase angle of inverter voltages raises the phase angle of coil currents.Meanwhile,the near-constant c

关 键 词：深海双向无线充电 海水介质 涡流损耗 相位差 最大效率点 

分 类 号：TM724[电气工程—电力系统及自动化]