基于标定原理的单磁极编码器设计

与光电编码器相比,磁性编码器结构简单,易实现微型化,且不受尘埃和结雾的影响。但其分辨率和精度较低且难以提高,严重制约了其发展和应用。针对单磁极编码器,提出一种基于标定查表的信号处理方式,用高精度光电编码器进行标定,采用FPGA(Field Programmable Gate Array)进行信号处理,采用两相电压分区间查表得到角度值,突破了技术瓶颈,实现了分辨率31 757 p/r、精度12位(4 096线)的角度输出。

位标器框架平台用单磁极磁电编码器设计

角位移传感器对于伺服控制闭环是一个重要的反馈元件,在军工和航天领域,旋转变压器和光电编码器本身的缺陷限制了其应用。为了弥补传统角位移传感器的不足,选择磁电编码器作为位标器框架平台的角位置反馈器件。依据校准查表信号细分算法研制出了一种单磁极磁电编码器,并设计了温漂补偿算法,以扩大工作温度适用范围,并为之设计制作了配套使用的校准和检测系统。经过实验验证,所研制的磁电编码器满足了位标器的应用要求。

单磁极加长降低表贴式永磁电机齿槽转矩

针对表贴式永磁电机存在的齿槽转矩问题,提出运用单磁极加长的方法来降低电机齿槽转矩。运用解析法推导出电机单磁极加长后齿槽转矩解析表达式,通过傅里叶分析,得到对电机齿槽转矩具有重要影响的变量B_(r(vz))。引入磁极加长系数η,研究如何选取η的数值削弱齿槽转矩。通过有限元仿真验证了所提方法的有效性。结果表明:通过合理选取磁极加长系数,将与齿槽转矩关键谐波分量有关的B_(r(vz))削减为零可有效降低电机齿槽转矩。

磁编码器算法分析与研究

磁编码器使用线性霍尔元件作为主体,结构简单,易实现微型化,适应恶劣环境能力强。实际应用中,磁编码器的分辨率和精度除受制于线性霍尔元件的精度外,也与AD采样精度、磁编码器算法有密切关系。在分析比较磁编码器的几种实现算法的基础上,给出了高精度的实现方案,在使用10 b it AD的基础上,可达到超过0.1°的分辨率。

内燃机用自由活塞永磁直流直线发电机分析

提出了一种新结构的自由活塞永磁直流直线发电机。电机为圆筒形,粘贴在动子支架上的永磁体由内向外沿径向充磁,通过内静子铁心与动子支架间的穿插配合,从静子上看动子只有一个磁极,静子上只有一组串联绕组,当永磁体动子朝一个方向运动时,电动势方向不变,可看作直流永磁直线发电机。通过三维有限元分析计算,指出设置磁路调整环的必要性;给出了有效削弱齿槽力波动的方法;得到了反映电机性能的电感、电动势和电磁推力等重要参数或曲线。

Quantum Entropy of Black Hole with Internal Global Monopole

Using the generalized uncertainty relation, the new equation of state density is obtained, and then the entropy of black hole with an internal global monopole is discussed. The divergence that appears in black hole entropy calculation through original brick-wall model is overcome. The result of the direct proportion between black hole entropy and its event horizon area is drawn and given. The result shows that the black hole entropy must be the entropy of quantum state near the event horizon.

Y（sl（2）） Algebra Application in Extended Hydrogen Atom and Monopole Models

We present the extended hydrogen atom and monopole-hydrogen atom theory through generalizing the usual hydrogen atom model and with a monopole model respectively, in which Y (sl(2) ) algebras are realized. We derive the Hamiltonians of the two models based on the Y(sl(2) ) and the generalized Pauli equation. The energy spectra of the systems are also given in terms of Yangian algebra and quantum mechanics.

Absolute multi-pole encoder with a simple structure based on an improved gray code to enhance the resolution

We developed a novel absolute multi-pole encoder structure to improve the resolution of the multi-pole encoder, realize absolute output and reduce the manufacturing cost of the encoder. The structure includes two ring alnicos defined as index track and sub-division track, respectively. The index track is magnetized based on the improved gray code, with linear halls placed around the track evenly. The outputs of linear halls show the region the rotor belongs to. The sub-division track is magnetized to N-S-N-S (north-south-north-south), and the number of N-S pole pairs is determined by the index track. Three linear hall sensors with an air-gap of 2 mm are used to translate the magnetic filed to voltage signals. The relative offset in a single N-S is obtained through look-up. The magnetic encoder is calibrated using a higher-resolution incremental optical encoder. The pulse output from the optical encoder and hall signals from the magnetic encoder are sampled at the same time and transmitted to a computer, and the relation between them is calculated, and stored in the FLASH of MCU (micro controller unit) for look-up. In the working state, the absolute angle is derived by looking-up with hall signals. The structure is simple and the manufacturing cost is very low and suitable for mass production.

Affine A_3^((1)) N=2 Monopole as the D Module and Aftine ADHMN Sheaf

A Higgs-Yang-Mills monopole scattering spherical symmetrically along light cones is given. The left incoming anti-self-dual α plane fields are holomorphic, but the right outgoing SD β plane fields are antiholomorphic, meanwhile the diffeomorphism symmetry is preserved with mutual inverse afiine rapidity parameters μ and μ^-1. The Dirac wave function scattering in this background also factorized respectively into the （anti）holomorphic amplitudes. The holomorphic anomaly is realized by the center term of a quasi Hopf algebra corresponding to an integrable conformal affine massive field. We find explicit Nahm transformation matrix （Fourier Mukai transformation） between the Higgs YM BPS （fiat） bundles （1） modules） and the affinized blow up ADHMN twistors （perverse sheafs）. Thus we establish the algebra for the ＇t Hooft Hecke operators in the Hecke correspondence of the geometric Langlands program.

Acceleration Effect in the Field of Neutron Star with Electric and Magnetic Charge and Magnetic Moment

The expression of acceleration in the external gravitational field of neutron star with electric and magnetic charge and magnetic moment is obtained. And some gravitational effects and properties of the field are discussed respectively from the contributions of the electric and magnetic charge and magnetic moment on the acceleration.

Topological Excitation in Skyrme Theory

Based on the C-mapping topological current theory and the decomposition of gauge potential theory, we investigate knotted vortex lines and monopoles in Skyrme theory and simply discuss the branch processes （splitting, merging, and intersection） during the evolution of the monopoles.

Branch Processes of Regular Magnetic Monopole

In this paper, by making use of Duan＇s topological current theory, the branch process of regular magnetic monopoles is discussed in detail. Regular magnetic monopoles are found generating or annihilating at the limit point and encountering, splitting, or merging at the bifurcation point and the degenerate point systematically of the vector order parameter field φ（x）. Furthermore, it is also shown that when regular magnetic monopoles split or merge at the degenerate point of field function φ, the total topological charges of the regular magnetic monopoles are stilI unchanged.

Vortex Lines and Monopoles in Electrically Conducting Plasmas

Based on the φ-mapping topological current theory and the decomposition of gauge potential theory, the vortex lines and the monopoles in electrically conducting plasmas are studied. It is pointed out that these two topological structures respectively inhere in two-dimensional and three-dimensional topological currents, which can be derived from the same topological term n^→·（Эin^→×Эjn^→）, and both these topological structures axe characterized by the φ-mapping topological numbers-Hopf indices and Brouwer degrees. Furthermore, the spatial bifurcation of vortex lines and the generation and annihilation of monopoles are also discussed. At last, we point out that the Hopf invaxiant is a proper topological invaxiant to describe the knotted solitons.

Vacuum-Induced Abelian and Non-Abelian Gauge Potentials in Cavity Quantum Electrodynamics

Gauge potential plays an important role in exploring exotic phenomena in the single- and many-body quantum systems.In this paper,we propose a scheme to create both new Abelian and non-Abelian gauge potentials by adiabatically controlling the degenerate Dicke model in cavity quantum electrodynamics.It is shown that a non-Abelian gauge potential is achieved only for a single atom,whereas an Abelianizen diagonal gauge potential is realized for the atomic ensemble.More importantly,two interesting quantum phenomena such as the geometric phase and the magnetic monopole induced by our created gauge potentials are also predicted.The possible physical realization is presented in the macroscopic circuit quantum electrodynamics with the Cooper pair boxes,which act as the artificial two-level atoms controlled by the gate voltage and the external magnetic flux.

Analysis and design of excitation system in homopolar inductor machine

The excitation system of the homopolar inductor machine(HIM)is analyzed and designed to establish the design approach and evaluation criteria of the excitation system.The finite element method is used to calculate the three-dimensional electromagnetic field in the HIM,and the distribution and characteristics of the magnetic field are described.The analytical method is applied to investigate the design process of the excitation winding.The ratio of the axial length of the armature winding to the excitation winding and the ratio of the axial length of the working air-gap to the non-working air-gap are investigated by the numerical calculation method.A prototype HIM is designed and manufactured,and some experiments are implemented to verify the correctness of the theoretical analysis and numerical calculation results.The research results show that the established design method of the excitation winding is practical and feasible.Under the conditions of constant excitation magnetomotive force or constant excitation power,the optimum range of the axial length ratio of the armature winding and the excitation winding is 0.45 to 0.5.The optimal axial length of the non-working air-gap can be determined by the ratio of the stator inner diameter and pole-pairs.

A Simple Approach to Air-Gap Armature Reaction Field Computation in Fractional-Slot SPM Multiphase Machines

Fractional-slot concentrated-coil electric machines are often used in those applications where a number of rotor poles close to the number of stator slots is required. A major criticality of such machines is the occurrence of large air-gap field harmonics due to winding distribution and to slotting effects. Predicting such harmonics analytically with adequate accuracy is a good way to significantly speed-up subsequent investigations, concerning the rotor effects of the field harmonics in terms of rotor losses. This paper proposes different analytical formulations for this purpose, covering the case of a generic number of stator phases and differing by how slotting effects are taken into account. The various approaches proposed are evaluated by comparing analytical results with finite-element analysis computations on a sample machine geometries.

写磁头对记录介质中输出信号的影响

在对垂直二层膜介质的输出信号随时间衰减的实验测试中 ,发现当使用单磁极磁头兼作读写磁头时 ,输出电压的变化量很大 .通过对这一现象的研究发现 ,影响介质退磁的外界原因主要有磁头主磁极膜磁畴的不稳定性和信号读出过程中主磁极对外界游离磁场的汇集吸收作用 .

新以太介质的物理化学理论

论文提出一种运用新以太介质物理理论来研究化学反应变化过程和物质结构的新方法。分子的结构有通过静电吸引的离子键和通过表面张力做功的原子键。而支配原子键结构的是一种质量Mq=7．61418×10^31克、电磁能量q=1．38867×10^-11静电库仑的单磁极予。气体分子中原子数目会随着温度、压力等外部条件的变化而发生变化。

Chain formation in a monolayer of dipolar hard spheres under an external field

The phase behavior of a monolayer of dipolar hard spheres under an external field, which makes all dipoles of the monolayer orientate along its direction, is investigated. Using integral equation theory in the reference hypemetted chain （RHNC） approximation we calculate the correlation functions, which are used to obtain the response matrix of grand potential with respect to density fluctuations. The smallest eigenvalue of this response matrix determines the stability of the monolayer. When the smallest eigenvalue approaches zero, the monolayer becomes unstable and the corresponding eigenvector characterizes this instability. At dilute densities, with decreasing temperature the dipoles of the monolayer begin to form chains and simultaneously condensate. At medium and high densities, however, the dipoles of the monolayer have a stronger tendency to form dipolar chains with decreasing temperature and there is no condensation. The part of specific heat related to potential energy is investigated and found to increase sharply near the temperature of dipolar chain formation. This is in accordance with a sharp decrease in potential energy induced by the formation of a dipolar chain.