查询词典 permanent field

In the experimental research, the levitation force of a HTS above a permanent magnetic guideway was first investigated in the case of zero-field cooling. The hysteresis of the levitation force curve and the interaction between a HTS and the applied magnetic field were explained by the Bean model, and the effect of the measuring precess on the levitation force was further analyzed.

实验研究中，首先研究了零场冷条件下高温超导体在永磁导轨上方的悬浮力特性，借助于Bean模型分析了悬浮力曲线的磁滞特性，阐述了高温超导体与外磁场间的相互作用原理，在此基础上进一步分析了悬浮力测试过程对悬浮力测试结果的影响。

The mathematical model of permanent magnet is a key problem for computing electromagnetic field of permanent magnet electrical machines.

引 言近年，随着高性能永磁材料的发展，永磁电机得到了迅猛的发展和广泛的应用。

Besides, numerical simulation of electromagnetic field of permanent magnet retarder was analyzed, and the design theory and method of permanent magnet retarder was studied.

主要研究内容和取得的结论包括： 1、永磁式缓速器磁路计算理论的研究。

The conversion between the electromagnetic energy and mechanical energy is completed in the magnetic field, and permanent magnet was applied in this designing to establish magnetic field to complete the conversion of energy.

电机中的电磁能与机械能的转换是在磁场中完成的，本设计中采用永磁体建立磁场，完成能量的转换。

It does not need an external power supply to excite the rotor field and hence the field winding and slip rings are eliminated. This thesis sets up the mathematical model of the permanent magnet synchronous motor in SIMULINK.

本文主要研究了永磁同步电机交流伺服系统的建模仿真和基于TMS320LF2407A数字信号处理器的系统实现，主要内容如下：建立了永磁同步电动机在dq坐标系中的数学模型，在SIMULINK中建立了仿真模型。

Permanent magnet can provide for a maximum intensity of the magnetic field around Tesla, Helmholtz coils and solenoids can provide alternating magnetic field or relatively uniform magnetic field, and solenoids can also be used to provide strength for the solenoid around 10 Tesla.

其中永磁铁能够提供强度最大为1特斯拉左右的静磁场，亥姆霍兹线圈和螺线管可提供交变磁场或相对均匀的磁场，也可用螺线管提供强度为10特斯拉左右的超强静磁场，电磁铁则可产生强度为几百毫特斯拉或特斯拉级的静磁场。

The opened magnetic circuit is composed as tow NdFeB permanent magnets and a top plate without U-yoke. After take analyzed deeply for the opened magnet circuit with FEMM (Finite Element Method Magnetics) we find out the field distributing that is separated into three sections . One is the main area what we called as positive field section. Beside the main field there are tow areas that are called the inverted field sections. Loudspeaker arise a very serious distortion when the voice coil moving into inverted field areas. The direction of induced current in the coil part of entered inverted field area is same with the current driving into loudspeaker so that total currents increas largely and heat increase rapidly. With more coils moving into inverted area the voice coil will take on negative inductance properties. It is the main reason that voice coil is burned by heating with increasing current due to arise negative inductance. So opened magnetic circuit is not suitable for the woofers in which the voice coil have wider displacement range. When using this kind magnetic circuit design, the voice coil moving range should be less than the range of positive field to avoid loudspeaker arise serious distortion and heating. Even though voice coil moving range is in the positive area, loudspeaker will still arise more distortion because the field distribution is very cliffy at tow sides of the positive area and full range of magnetic field distribution is not parallel that will arise distortion. Base on above reasons, opened magnetic circuit is not an ideal magnetic circuit for low-frequency loudspeakers. But it can be used in mid-range or high-frequency productions.

开式磁路是由2片钕铁硼磁铁和主导磁板和导磁垫片组成，我们在实践过程中发现这种磁路结构不适合于低频扬声器的使用，我们通过使用FEMM（Finite Element Method Magnetics）软件包对该磁路进行了分析，该磁路的磁场范围被分成3个区域，其中在主导磁板附近形成一个正向磁场，在正向磁场的两边存在反向的磁场，音圈在工作时有很大一部分进入了反向磁场中，在反向磁场内线圈的感应电流方向与驱动电流方向相同，使得音圈呈现出负感抗特性，由于音圈的负感抗特性引起电流的增加导致音圈发热甚至烧毁，因此在扬声器中使用开式磁路时，音圈的运动范围应控制在正向磁场范围之内，否则音圈运动到反向磁场区域时将会产生很大的失真和发热，即使在设计时已经将音圈的运动范围控制在正向磁场范围之内，由于正向磁场的2个边缘磁场强度衰减太快，同时开式磁路中磁场的分布不是平行的，而是自由发散的分布，这样肯定会导致扬声器的非线性失真，因此我们得到的结论是：开式磁路并不是一个理想的磁路，它不适合于低频扬声器的使用，但它还可以应用于中高频扬声器。

At last ,it drew a conclusion that summarined the design thought of permanent magnetic brushless DC motor control system after absenting waves of controllers work . Permanent Magnetic Brushless DC motor control system canbecome main power source in ship electric propulsion field ,and the research have important s signification.

最后，在控制系统实际运行时对波形进行了观测，给出了结论，总结了无刷直流电机控制系统的设计思想，提出永磁无刷直流电机将成为船舶电力推进的主要动力，对其控制系统的研究具有广泛的应用价值。

Two fruits of the item, Low Speed and High Torque Permanent Magnetic Synchronous Motor, and Permanent Magnetic Synchronous Gearless Elevator Traction Machine, have passed the science and technique fruit identification. Two fruits are all appraised as International Lead Level in the correlative field by the indentification committee. Two fruits have become industrialization now, and have achieved outstanding economic benefits and society benefits.

本项目的两项研究成果&低速大转矩稀土永磁同步电动机&和&永磁同步无齿轮电梯曳引机&，已通过科学技术成果鉴定，均被评价为&国际领先水平&，并已经产业化，取得了显著的经济效益和社会效益。

Firstly, the relationship between the magnetic pole state of active magnetic pole and the running state of passive magnetic pole was analyzed. The electromagnet's four magnetic pole state and switch sequence, which can drive permanent magnet rotate, were ascertained. Secondly, taking one of magnetic pole state NS (N denotes electromagnet's left magnetic pole and S right magnetic pole) as an example, the distribution of space magnetic field was studied. In addition, the mathematical model of space magnetic field was set up based on the magnetic circuit fundamental and using the method of magnetic analysis and modeling. Lastly, the four states' mathematical model of space magnetic field was solved by using the MATLAB.

首先，分析系统主动磁极磁极状态和从动磁极转动状态之间的关系，确定驱动永磁体转动的电磁体4个磁极状态及切换顺序；其次，基于磁路基本原理，通过磁场分析和建模，以电磁体4个磁极状态之一的NS（N表示其左极、S为右极）为例，对电磁体的空间磁场分布进行研究并建立空间磁场数学模型；最后，以MATLAB为平台对4个磁极状态的空间磁场数学模型进行求解，将求解结果与实验数据进行对比。

He is the most remarkable man that I have ever known.

他是我知道的人中最值得注意的人。

Increased appearance of lymphocele was noticed in patients with diabetic nephropathy, congenital malformations of the urinary tract, and inflammatory diseases, including glomerulopathy and extraglomerular ones, after high-voltage radiotherapy and after removal of the renal graft.

经过高压放射疗法和切除移植肾后，在糖尿病肾病患者、泌尿系统先天性畸形患者和炎症患者身上发现淋巴囊肿有所增加，包括肾小球病和球外疾病等。