【作者】 朱英伟；

【导师】 王豫；

【作者基本信息】 西南交通大学 ， 电工理论与新技术， 2011， 博士

【摘要】 电磁推进或者称为电磁发射(Electromagnetic Launch, EML),是指根据磁场与电流之间的相互作用效果,利用电磁力推进或驱动物体,使之加速运动达到所需应用要求的一类发射装置。电磁推进器具有发射质量范围大、出口初速度高、能源简易、发射效率高、工作性能优良、可控性好和结构多样等优点,使其在未来军事武器、科学研究、航天和交通、民用工业等相关领域有着广泛的应用潜力。按照推进装置结构和工作原理的不同,常规电磁推进器基本上可以分为三大类：导轨式(轨道炮Railgun)、同轴线圈式(线圈炮Coilgun)和重接式(Reconnection gun)。对于大质量和大推力的发射要求,常规电磁推进器存在一些原理性缺陷或面临一定技术困难。导轨型电磁推进器的两条平行导轨和电枢是在兆安级电流下进行工作的,电枢、导轨等部件在发射瞬间要承受极大的热流和电磁应力冲击,容易造成导轨的严重烧蚀与表面剥落,本身高速运动与电接触摩擦就是一对矛盾问题；同轴直螺线管线圈型推进器对抛体电枢的电磁力主要分量为径向力,表现为径向压缩力或径向扩张力,而用于对抛体电枢加速的轴向分量力则较小,且轴向加速力远小于径向作用力,因此,线圈型电磁推进器的电磁力利用率不高。本论文在国内外首次提出应用径向磁场与环向电流相互作用进行电磁推进的思想,建立了多极矩场线圈型电磁推进模式,并对多极矩场线圈型电磁推进系统进行分析和设计。论文首先对线圈型电磁推进的动力学过程进行分析,给出了导轨型和线圈型电磁推进的数学模型,并对常规线圈型电磁推进模式的关键技术进行研究,发现存在问题并加以改进；接着,提出应用径向磁场与环向电流相互作用进行电磁推进的思想,建立了多极矩场线圈型电磁推进模式,对多极矩磁场构型进行数学解析,分析多极矩场电磁推进模式的数学模型和机电方程,并给出系统方程的求解方法；然后,采用电磁场有限元方法仿真计算多极矩场电磁推进的瞬态发射过程,对带有弹射线圈的单级八极矩线圈推进系统进行瞬态运动仿真,结果发现,多极矩场电磁推进模型解决了传统线圈型电磁推进器轴向电磁力分量不足导致加速力较小的缺陷,并对抛体电枢提供了稳定的悬浮恢复力；对三级并排八极矩线圈型电磁推进器的瞬态发射仿真,结果表明,多级加速效果明显,该模式具有向多级高速扩展的潜力；最后,对多级扭转八极矩场线圈型电磁推进器进行系统设计,扭转多极矩场线圈型电磁推进器是对并排多极矩场线圈的结构改进,理论分析和仿真结果显示,该推进模式使抛体电枢具有自旋运动,提高了抛体电枢的运动稳定性；同时,该部分还对电源电路与检测控制系统进行设计和优化,设计了多极矩线圈的分组供电模式,给出了脉冲电流波形与触发放电位置相匹配和优化设计准则。多极矩场电磁推进模式能够改善目前电磁推进器的性能,适合大质量、大口径抛体电枢向高速和高动能发射,具有电磁推力大、出口速度高,悬浮稳定的发射性能。将多极矩场电磁推进技术应用到交通运输,可以设计成多极矩场电磁驱动机车,具有高速、重载、平稳和高效能的优点；将多极矩场电磁推进技术应用到航天工程,可以设计成火箭的助推装置,能够实现大质量和大推力的发射。更多还原

【Abstract】 Electromagnetic launch (EML), sometimes called electromagnetic propulsion, is suggested as that uses electromagnetic force to propel or drive objects according the interaction between magnetic field and current. The launch goal is to accelerate objects to high speed or hypervelocity. Electromagnetic launch has such advantages as no launch mass limit, high muzzle velocity, and simplified energy source, higher launch efficiency, and good working performance, easily controllable and large variety of launch structure. The most promising application for electromagnetic launch is used by the military weapons, scientific research, spaceflight and transportation, and civil industry has extensive application potential.According to the difference of launcher structure and working mode, conventional electromagnetic launcher is divided into three types:rail launcher (Railgun), coil launcher (Coilgun) and reconnection launcher (Reconnection gun). For the requirements of big mass and huge propulsion force transportation, conventional electromagnetic launchers have some principle limitations and confront several technique troubles. The two parallel rails and armature of rail launcher are working in the current of megampere, and they endure huge thermal and magnetic stress impact in the launch transient. That always causes the rails ablation and interface erosion. Intrinsically, the hypervelocity motion and electric contact friction are inherent contradiction. The coaxial solenoid coil launcher has greater radial component of electromagnetic force, represented as radial compress force or distension force. The axial force of coil launcher used to accelerate the projectile is much littler than the radial force and the utilizable efficiency of electromagnetic force is not high. For the first time in the world, this paper presents a new idea of radial magnetic field interacting with azimuthal current for electromagnetic launch, and proposes a novel multipole field electromagnetic launch mode. This paper gives the system design and analyses the performance of multipole field electromagnetic launcher.Firstly, the paper analyses the dynamics of coil launcher, and gives the mathematic model of rail launcher and coil launcher. The key techniques of conventional electromagnetic launch mode are indicated and improved. Then, the idea of radial magnetic field interacting with azimuthal current to launch object is presented and the concept of multipole electromagnetic launcher. The multipole electromagnetic launch mode is established and the multipole magnetic field configuration is mathematical resolved. The mathematical model and mechanical-electric equations of multipole electromagnetic launch mode are obtained. The solution method of system equations is presented. After the theoretical analysis, the transient launch process of multipole electromagnetic launcher is simulated with electromagnetic field finite element method (FEM). The simulation results of single stage octapole field electromagnetic launcher with catapult coil indicate that multipole electromagnetic field launcher conquer the shortcoming of conventional coil launcher, which with less axial component of electromagnetic force used to accelerate the projectile. Moreover, the multipole coils provide a restoring force for the projectile which could keep the projectile maglev and accelerate stability. Then, the three stage appositional octapole field electromagnetic launcher is simulated and analyzed. The simulated results indicate that acceleration performance of multistage launcher is obvious acceptable, and the launch mode has the potential of hypervelocity to expand with multi stages. In the end, an improved launch mode called multi-stage twisty multipole electromagnetic launcher is presented. Then three-stage twisty octapole field electromagnetic launch system is designed and simulated. The theoretic analysis and simulation results indicate that this launch mode makes the projectile with spinning motion, which improves the flying stability of projectile motion. This part of paper also gives the design of power supply circuit, detect and control system. The group power supply mode of multipole coils is proposed. Finally, the optimal design and match of pulsed current wave with discharge position is presented.Multipole electromagnetic field launch mode could improve the acceleration performance of conventional coil launcher, and they fit for large mass and big caliber projectile to accelerate to high speed and high kinetic energy. Multipole electromagnetic field launcher has the advantage of huge thrust force, high exit velocity and steady maglev characteristic. We suggest this launch mode could be applied in the transportation locomotive, designed as multipole electromagnetic levitated trains. This train has the potential of high speed, over loading, stabilization and efficiency. Furthermore, multipole electromagnetic field launch mode could be used in the field of spaceflight engineering, and designed as satellite and space shuttle’s launch equipment. This launcher could easily achieve large mass and hypervelocity launch.更多还原