【作者】 郑陆海；

【导师】 金建勋；

【作者基本信息】 电子科技大学 ， 检测技术与自动化装置， 2011， 博士

【摘要】 自高温超导体在1986年发现后,其应用技术也逐步发展起来。目前,高温超导材料的主要应用形式为块材,带材和薄膜,其中高温超导块材基于其迈斯纳效应和强磁场俘获能力而具有广泛应用于磁悬浮运输、电机、高能物理等领域的潜力。本论文系统总结了高温超导材料在电机驱动和磁悬浮中的应用,基于相关理论和数值分析,研制出了国内首台应用高温超导块材磁体阵列作为电机次级的高温超导直线同步电动机,同时该样机复合了高温超导磁悬浮子系统,实现了无摩擦悬浮推进,并具有自悬浮和自导向功能,使得电机推力大,效率高,控制技术简单。本论文围绕与该高温超导直线电机推进系统模型相关的关键技术问题开展下述研究工作。首先完成了高温超导直线同步电动机的结构设计,包括长初级定子和两种不同结构的高温超导块材磁体阵列次级动子。根据所设计电机的实际结构与尺寸,结合超导块材磁体理论模型,建立了高温超导直线同步电动机的数值模型和等价有限元模型,推导出了新型直线电机的主要电磁参数计算公式,通过有限元仿真研究了电机的电磁推力和法向力特性,以及齿槽力特性,为后续的实际样机性能测试奠定理论基础。其次完成了用于高温超导直线同步电动机次级动子悬浮和导向的高温超导磁悬浮子系统的结构设计,包括三种永磁轨道物理模型,并实际开发了表面置磁型和磁通聚集型永磁轨道。为能够采用数值方法研究高温超导磁悬浮系统的悬浮力和导向力特性,本文采用等价电流片方法建立了不同结构类型永磁轨道的磁场分布数值模型,并通过实验测试验证了所建模型的准确性。基于建立的等价电流片永磁轨道数值模型,作者分别建立了矩形和圆柱体形高温超导块材在永磁轨道上方的悬浮力和导向力模型,为高温超导磁悬浮系统的悬浮/导向性能研究,提供了有效的理论分析手段。在完成样机研制的基础上,开展了用于高温超导直线同步电动机次级的高温超导块材的充磁特性研究,包括直流场冷/零场冷,以及脉冲零场冷充磁特性,并比较了不同充磁方法的特点,探索可实际用于直线电机的高温超导块材的最佳充磁方法。针对高温超导块材磁体的交场应用环境,率先对YBCO(Y-123)高温超导块材磁体在直线电机产生的交变行波磁场中的电磁特性展开实验研究,获得了高温超导块材磁体俘获磁场在直线电机中不同交变外场条件下的衰变特性,为提高超导块材磁体在交场环境下的应用性能提供了理论与实验依据。基于实验研究成果,针对设计的两种不同结构的高温超导块材磁体阵列次级,分别设计了用于获得交替磁极的新型充磁系统,解决了在高温超导直线电机应用当中交替磁极磁体阵列充磁的关键技术问题。针对所研制的高温超导直线同步电动机的特点,开发了相应的直线电机控制系统和测试系统。应用所开发的直线电机测控平台,对高温超导直线同步电动机的主要运行参数进行了测试,系统研究了电机的推力和法向力特性,得到的重要结论为高温超导直线同步电动机的优化电磁设计和优化控制策略选择提供了依据。在现有样机设计的基础上,作者提出了两种采用双边型高温超导直线同步电动机实现推进的新型高温超导磁悬浮与直线推进系统模型,并分别对它们在飞机电磁弹射系统和磁悬浮列车中的应用做了探讨性研究。基于实际应用需求,作者给出了实际设计参数,并通过有限元仿真得到其性能特征和优化设计方案。更多还原

【Abstract】 Since the discovery of high temperature superconductors (HTS) in 1986, HTS application techniques have been widely developed. Currently, the applicable HTS materials are mainly in the forms of bulks, tapes and thin films, among which, HTS bulks based on Meissner effect and strong magnetic field trapping ability have been widely adopted for potential applications in the maglev, city metro, electric machines, linear motor, high-energy physics etc.After comprehensive research survey of HTS materials applied to HTS linear motors and HTS magnetic suspension systems, the first prototype of HTS linear synchronous motor (HTSLSM) with HTS bulk magnet array as its secondary has been proposed and developed in our laboratory. The HTSLSM in combination with an HTS magnetic suspension sub-system, has been developed in a novel HTS magnetic suspension and linear propulsion system, which brings higher efficiency for its operation with self-levitation and self-guidance capacities without any slide friction loss. Principal work focuses on the studies of the related HTSLSM models and key technologies as summarized below.Firstly, electromagnetic designs of the HTSLSM, including a long-primary stator and an HTS bulk magnet array secondary have been conducted. Two novel magnetization systems for the HTS bulk magnet array has been designed, which can be used to magnetize the HTS bulk array magnet with alternate magnetic poles efficiently. According to practical requirement and the practical parameters of the developed HTSLSM, the theoretical model of the HTS bulk magnet, the numerical model and equivalent finite element analysis (FEA) model of the HTSLSM have been built up, and its electromagnetic parameters are also calculated. The traits of electromagnetic thrust, normal force and the cogging force of the HTSLSM have also been obtained by FEA, which form the theoretical bases for the related measurements on the HTSLSM prototype.Secondly, the HTS magnetic suspension system have been designed with three different types of permanent magnet guideways (PMGs), including surface mounted PMG, flux concentration PMG and Halbach array PMG. In order to study the suspension and guidance characteristics of the HTS magnetic suspension system by numerical method, the equivalent current sheet (ECS) method is used to build up the magnetic field distribution models of the PMGs, which have been verified by relevant measurements. The interaction models between one rectangular or cylindrical HTS bulk and PMG have been built up by numerical method based on the ECS models of the PMGs, which provide effective theory approaches to study the levitation and guidance performance of the HTS magnetic suspension system.Moreover, the experiments to study the magnetization characteristics of the developed HTSLSM, including the DC field-cooled (FC), DC zero-field-cooled (ZFC), and pulse magnetizations for the HTS bulk, have been carried out. The results are helpful to find an optimal magnetization method to obtain HTS bulk magnets for the practical applications. The experimental investigations on the electromagnetic characteristics of the YBCO HTS bulk magnet exposed to the external AC traveling wave magnetic field generated by the linear motor primary have been carried out, and the trapped magnetic field attenuation characteristics of HTS bulk magnet exposed to the external AC magnetic field have been obtained, which forms the theoretical and experimental basis to improve the application performance of HTS bulk magnet for the AC applications.Based on the characteristics of the developed HTSLSM, the corresponding control and measurement systems for the HTSLSM have been developed. By the help of the control and measurement platform, main electromagnetic parameters, thrust and normal force of the HTSLSM have been measured. The methodology is verified by the optimal electromagnetic design and control algorithm analysis of the HTSLSM.Based on the developed HTSLSM model, two types of HTS magnetic suspension and linear propulsion systems driven by a double-sided HTSLSM have been proposed. The applications of the HTS suspension and linear propulsion system on the electromagnetic aircraft launch system (EMALS) and Maglev have been studied, and the design parameters of the propulsion system are obtained based on their practical requirements. Theoretical analysis has been carried out by the FEA.更多还原