permanent magnet actuator,intrinsic

关键词:low voltage control,permanent magnet actuator,intrinsic

safety,vacuum contactor
摘要:This paper reports a new application of permanent magnet

actuator for vacuum contactors.A novel permanent magnet(PM)

actuator to drive a vacuum contactor Neodymium Magnets with intrinsically safe and

low supply voltage is proposed.PM is mounted on the static iron

of the contactor to enhance its holding force and

reliability.While only one coil is used to break the vacuum

contactor,two series coils http://www.999magnet.com/products/110-sintered-neodymium-magnets are deployed to yield a high

magnetomotive force to realize the making operation.The

electrical circuit equation,mechanical equation and magnetic

field are all coupled in the simulation.A prototype is

manufactured and tested to validate and showcase the performance

of the contactor which is equipped with the proposed PM actuator.

magnetic field properties

作者:孙献静;邓昌东;康文;
关键词:CSNS, RCS, transient electromagnetic simulation, thermal

analysis
单位:Institute of High Energy Physics,Chinese Academy of

Sciences;
摘要:Due to the large eddy currents at the ends of the quadrupole

magnets for CSNS/RCS, the magnetic field magnetic materials properties and the heat

generation are of great concern. In this paper, we take transient

electromagnetic simulation and make use of the eddy current loss

from the transient electromagnetic http://www.999magnet.com results to perform thermal

analysis. Through analysis of the simulated results, the magnetic

field dynamic properties of these magnets and a temperature rise

are achieved. Finally, the accuracy of the thermal analysis is

confirmed by a test of the prototype quadrupole magnet of the

RCS.

phosphating;ultrasonic

关键词:sintered NdFeB magnet;phosphating;ultrasonic

wave;corrosion resistance
摘要:The corrosion behavior of a NdFeB magnet obtained at room

temperature,with and without ultrasonic were investigated.The

corrosion resistance was investigated by neodymium standard state corrosion immersion

tests in 3 wt%neutral NaCl solutions,potentiodynamic polarization

tests and electrochemical impedance spectroscopy(EIS).The

morphology of the conversion coatings on NdFeB surface were

analyzed by scanning electron http://www.999magnet.com/products/112-neodymium-standard-state microscopy(SEM).And the forming

mechanism of coatings was studied by potential-time curves.The

tests of corrosion resistances show that the combination of

phosphating treatment with ultrasonic will further improve the

corrosion resistance of the NdFeB.The SEM also confirms that

phosphating coating under ultrasonic is more homogeneous and

compact.

Chemistry, Peking University

作者:顾菡珍,吴念祖,叶于浦
关键词:切吸:4375,北京大学:3789,新金属材料:3777,翻台:3299,钢铁研究

:2975,万宁:2803,化学系:2785,剑兰:2783,角门:2573,百万:1580
单位:Department of Chemistry, Ball Neodymium Magnets
http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php Peking University





,Department

of Chemistry, Peking University





,Department of Chemistry,

Peking University
摘要:<正> In the preceding article, the approach was made mainly

to the effect of various factors on the magnetic performance in

the preparation of SmCo_5 by the Reduction-Diffusion Process.

Some of the samples were produced using water pulvermation and

solid phase sintering, which gave rather satisfactory results. In

order to make this technology applicable to production on a

larger scale it is

Engieering, Academia Sinica,

作者:韩朔,张超骥,旷远达,冯之鑫,罗昆崙,宋守森,黄惠志,高志远,李克文

,陈月莲
单位:Institute of Electrical Engieering, Block neodymium magnet
http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php Academia Sinica,

Beijing





,Institute of Electrical Engieering, Academia

Sinica, Beijing





,Institute of Electrical Engieering,

Academia Sinica, Beijing





,Institute of Electrical

Engieering, Academia Sinica, Beijing





,Institute of

Electrical Engieering, Academia Sinica, Beijing





,Institute

of Electrical Engieering, Academia Sinica, Beijing





,

Institute of Electrical Engieering, Academia Sinica, Beijing







,Institute of Electrical Engieering, Academia Sinica, Beijing







,Institute of Electrical Engieering, Academia Sinica, Beijing







,Institute of Electrical Engieering, Academia Sinica, Beijing
摘要:<正> Superconducting dipole and quadrapole magnets with high

field homogeneity and high gradient are required in high energy

physics experiments.There are two types of dipole magnet, one has

iron shield and the other has not. The latter is dangerous

Free piston (FP), Linear alternator (LA),

关键词:Free piston (FP), Linear alternator (LA), Internal combustion engine (ICE), Finite element method (FEM)
摘要:We proposed the flat-type permanent magnetic materials
http://www.999magnet.com magnet linear alternator (LA) for free piston linear alternators (FPLAs) instead of the tubular one. Using the finite element method (FEM), we compare these two kinds of LAs. The FEM result shows that the flat-type permanent magnet LA has higher efficiency and larger output specific power than the tubular one, therefore more suitable for FPLAs, and that the alternator design can be optimized with respect to the permanent magnet length as well as the air gap.

Jointly supported by the National Natural Scien

摘要:<正>Jointly supported by the National Natural Science Foundation of China,Ministry of Science and Technology and Chinese Academy of Sciences,Ma Xucun's group in CAS Institute of Physics Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets and Condensed Matter Physics National Lab,in cooperation with Xue Qikun's research team in the Department of Physics of Tsinghua University,studied the super exchange mechanism in cobalt phthalocyanine(CoPc)thin films


关键词:sintered NdFeB permanent magnet; Ni-P/TiO2 composite film; sodium chloride solution; corrosion resistance
摘要:The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (icorr) and the polarization resistance (Rp) of Ni-P/TiO2 film are 0.22 μA/cm2 (about 14% of that of Ni-P coating),and 120 kΩ·cm2 (about 2 times of that of Ni-P coating),respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.

Elevator door system, Tubular permanent magnet linear

关键词:Elevator door system, Tubular permanent magnet linear synchronous motor (TPMLSM), Finite element analysis(FEA)
摘要:A novel elevator door driven by tubular permanent magnet linear synchronous motor (TPMLSM) is presented. This TPMLSM neodymium price
http://www.999magnet.com/products/142-neodymium-price applies axial magnet array topology of the secondary rod, air-cored armature windings and slotless structure of the forcer to improve the stability of the thrust. The influence of two major dimensions, the pitch and radius of the permanent magnet (PM), on magnetic field was studied and the best values were given by the finite element analysis (FEA). The magnetic field, back EMF and thrust of the motor were analyzed and the PM size was optimized to reduce the harmonic components of the magnetic field and improve the performance of the motor. Predicted results are validated by the experiment. It is shown that the performance of the motor and the novel elevator door system is satisfying.

Permanent Magnet Synchronous Motor

关键词:Permanent Magnet Synchronous Motor, Passive system, State observer
摘要:Passive system theory was applied to propose a new passive control method with nonlinear observer of the Permanent Magnet Synchronous Motor chaotic system. Through constructing a Lyapunov function, neodymium price
http://www.999magnet.com/products/142-neodymium-price the subsystem of the Permanent Magnet Synchronous Motor chaotic system could be proved to be globally stable at the equilibrium point. Then a controller with smooth state feedback is designed so that the Permanent Magnet Synchronous Motor chaotic system can be equivalent to a passive system. To get the state variables of the controller, the nonlinear observer is also studied. It is found that the outputs of the nonlinear observer can approximate the state variables of the Permanent Magnet Synchronous Motor chaotic system if the system’s nonlinear function is a globally Lipschitz function. Simulation results showed that the equivalent passive system of Permanent Magnet Synchronous Motor chaotic system could be globally asymptotically stabilized by smooth state feedback in the observed parameter convergence condition area.

permanent magnet

关键词:rare earths; permanent magnet; settling; separation
摘要:Mechanism and characteristics of magnetic particle′s solid-liquid separation in rare earth magnetic Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets field were studied. Magnetic force resulted from magnet is a function of magnet′s magnetization M and particle′s position x. It weakens significantly with increase of spatial distance x. Two groups of comparative experiments were carried out. It was found out that presence of Nd-Fe-B magnet gives much shorter free settling and pressing time in gravitational separation and shorter pressing time in centrifugal separation. Expressions for effective acting distance of permanent magnetic field in gravitational settling and centrifugal settling were summarized based on the analysis and experiments.

NdFeB magnets; alloying; coercivity

作者:宋晓平,杨森,王献辉,孙占波,孙军
关键词:rare earths; NdFeB magnets; alloying; coercivity
摘要:Alloying elements Cu and Ti were added to the intergranular regions of sintered NdFeB magnets and their effects magnetic materials
http://www.999magnet.com on microstructure and magnetic properties were investigated. The results show that small amounts of Cu/Ti additives can enhance the coercivity greatly and have little effect on the remanence of the magnets, while Ti content is less than 1  2%. The improvement of the coercivity can be attributed to the segregation of Cu and Ti on the surface of main phase, which inhibits the growth of main phase grains during sintering. At the same time, segregation of Cu and Ti can also prevent the magnetic coupling of Nd  2Fe    14  B grains to a certain degree and impede effectively the propagation of reversed domain walls through the magnetic phase grains. As the Ti content increased above 1  2% a strip  like Ti  rich phase appears in the intergranular region, resulting in the dramatic reduction of the remanence of Nd  Fe  B magnets. Compared with the single alloying method, the combined alloying of intergranular regions is more efficient to modify the properties of NdFeB magnets.

Particle size, Particle

关键词:Rare earths, NdFeB neodymium standard state
http://www.999magnet.com/products/112-neodymium-standard-state powder, Particle size, Particle









distribution, Magnetic properties
摘要:ＰｏｌｙｍｅｒｂｏｎｄｅｄＮｄＦｅＢｐｅｒｍａｎｅｎｔｍａｇｎｅｔ，ｆｉｒｓｔｌｙａｐｐｅａｒｅｄｉｎ１９８０ｓ，ｉｓａｎｅｗｔｙｐｅｏｆｐｅｒｍａｎｅｎｔｍａｇｎｅｔｉｃｃｏｍｐｏｓｉｔｅ，ｗｈｉｃｈｃｏｎｓｉｓｔｓｏｆＮｄＦｅＢｐｅｒｍａｎｅ...


作者:刘湘涟,何建平,董清飞,周寿增
关键词:rare earths; NdFeB-type magnet; sintering; grain growth kinetics
摘要:The Nd  2Fe    14  B grain growth kinetics in sintered NdFeB magnets with nominal compositions of   Nd    30+x  Dy    1.5  Fe    67.08-x  Al    0.4  B    1.02     (%, x=0, 3) was studied. The grain size parameters were determined by means of the linear intercept method on SEM secondary electron images. It is observed that the grain growth process is more sensitive to sintering temperature than to sintering time although the grain size rises with both sintering temperature and time. It is also found that magnets prepared from the pre-alloy powder with a higher oxygen content exhibit a lower grain growth rate and magnets made from the pre-alloy powder with a broader particle size distribution demonstrate a higher grain growth rate. It is believed that the presence of appropriate amounts of Nd oxides effectively impedes the grain growth process and a larger difference in sizes between pre-alloy powder particles significantly accelerates the grain growth process. On the basis of experimental results, the grain growth exponent and the corresponding activation energy were obtained. A possible grain growth mechanism in NdFeB magnets during sintering was briefly discussed.

microstructure; magnetic force microscope

作者:吕友胜;陈翌庆;苏勇;成问好;熊永飞;依晓飞;周庆涛;
关键词:NdFeB; microstructure; magnetic force microscope; domain structure; rare earths
单位:School of Materials Science magnetic materials
http://www.999magnet.com and Engineering  Hefei University of Technology,School of Materials Science and Engineering Hefei University of Technology,School of Materials Science and Engineering Hefei University of Technology,Earth Wind Advance Magnetic Material Co. Ltd.,Earth Wind Advance Magnetic Material Co. Ltd.,Earth Wind Advance Magnetic Material Co. Ltd.,School of Materials Science and Engineering Hefei University of Technology,,Hefei 230009 China,Hefei 230009 China,Hefei 230009 China,Lujiang,Anhui,China,Lujiang,Anhui,China,Lujiang,Anhui,China,Hefei 230009 China
摘要:A new alloy of Nd33.5Dy0.99Febal.Al0.52Cu0.1B1.15 (%, mass fraction) was fabricated by powder metallurgy. The effects of Dy, Al and Cu additions on the microstructure and magnetic properties of sintered NdFeB magnet were investigated. The additions of Dy, Al and Cu are effective to refine grains and improve coercivity. Moreover, suitable amounts of Dy, Al and Cu lead to a demagnetization curve with good rectangularity. It is found that the sintered NdFeB magnet has relatively high magnetic performance of Br=12.17 kGs, jHc=13.52 kOe and (BH)max=34.71 MGOe. The sintered NdFeB sample was examined by magnetic force microscope which revealed the domain structures at the surface. It is revealed that the mean Nd2Fe14B grain size is significantly larger than the average scale of the magnetic contrast. An explanation about this is that most Nd2Fe14B grains in sintered NdFeB alloy are dominated with the multidomain structures when the magnet is in thermally demagnetization state.

sintered NdFeB permanent magnet

作者:于升学;陈玲;
关键词:sintered NdFeB permanent magnet; Zn-Cr coating; magnet property; anticorrosion property; rare earths
单位:Department of Applied Chemistry  Yanshan University Qinhuangdao 066004 China,Department of Applied Chemistry Yanshan University Qinhuangdao 066004 China,
摘要:Zn-Cr coating was prepared Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets on the surface of sintered NdFeB permanent magnet samples and preparation parameters were established. The anticorrosive property of Zn-Cr coating on NdFeB was studied by whole-immersion test in NaCl solution and compared with that of zinc plating and nickel plating on NdFeB. Open-circuit potential and self-corrosion current of NdFeB samples with and without Zn-Cr coating were measured. The micro-morphology and composition of Zn-Cr coating were analyzed through SEM, XPS, EDS and XRD. The effect of Zn-Cr coating on magnetic property of NdFeB magnet was also investigated. It is exposed that Zn-Cr coating is anodic type coating for NdFeB magnet, and provided substrate electrochemical protection, barrier protection and passivation protection. The anticorrosion property of NdFeB magnet is obviously enhanced by Zn-Cr coating while the magnet property of NdFeB magnet changed little.

nanocomposite magnets; melt spinning

作者:王伟,倪建森,徐晖,周邦新,李强,王占勇
关键词:nanocomposite magnets; melt spinning; exchange coupling; rare earths
单位:Institute of Materials, neodymium prices
http://www.999magnet.com/products/142-neodymium-prices Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China








,Institute of Materials, Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China








,Institute of Materials, Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China








,Institute of Materials, Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China








,Institute of Materials, Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China








,Institute of Materials, Research Center of Nano-Science and Nano-Technology, Shanghai University, Shanghai 200072, China
摘要:Nd_(11)Fe_(71)Co_8V_(1.5)Cr_1B_(7.5) magnet was prepared by melt-spinning and subsequently annealed. The effects of the wheel speed on the magnetic properties and microstructure were studied. The results reveal that fine nanocomposite microstructure consisting of Nd_2Fe_(14)B and α-Fe phases can be developed at an optimum wheel speed of about 21 m·s~(-1). After optimal annealing (640 ℃×4 min), magnetic properties of B_r=0.64 T, (()_jH_c)=903.5 kA·m~(-1) and (BH)_(max)=71 (kJ·m~(-3)) were obtained for the bonded magnets. The addition of Cr element significantly reduces grain size, increasing the intrinsic coercivity and maximum magnetic energy product.

Calibration,Commissioning

关键词:Booster,Magnet,Calibration,Commissioning
摘要:The Shanghai Synchrotron Radiation Facility (SSRF) is a low

emittance third-generation synchrotron radiation light source

under commissioning. The excitation Neodymium Magnets curve calibration for the

booster magnets is important to provide the magnet current

configurations as reference. Calibration studies give the

polynomial coefficients of each type of magnets and provide the

magnet current configurations under different beam energies as

beam is ramped at speed of 2 Hz. http://www.999magnet.com/products/110-sintered-neodymium-magnets The applications of calibration

in booster commissioning which show the accuracy of the magnetic

excitation curve calibration are also discussed.

rare earth permanent magnets

者:彭龙;杨青慧;张怀武;徐光亮;张明;王敬东;
关键词:rare earth permanent magnets; SmCo alloys; coercivity;

temperature coefficient
单位:State Key Laboratory of Electronic Thin Films and Integrated

Devices  University of Electronic Science and Technology of

China,State Key Laboratory of neodymium prices Electronic Thin Films and

Integrated Devices University of Electronic Science and

Technology of China,State Key Laboratory of Electronic Thin Films

and Integrated Devices University of Electronic Science and

Technology of China,Shcool of Materials Science and Engineering

Southwest University of Science and Technology,Southwest

Institute of Applied Magnetics,Southwest Institute of Applied

Magnetics,,Chengdu 610054,China,Chengdu 610054,China,Chengdu

610054,China,Mianyang 621010 China,Mianyang 621000 China,Mianyang

621000 China
摘要:Sintered Sm(CobalFexCu0.1Zr0.03)7.5 (x=0.09-0.21) permanent

magnets with higher Fe content were found to have higher

remanence Br and maximum energy http://www.999magnet.com/products/142-neodymium-prices product (BH)max at room

temperature. Br and (BH)max reached maximum of 0.96 T and 176.7

kJ/m3, respectively at room temperature when the Fe content x

reached 0.21. However, the intrinsic coercivity Hci at room

temperature increased gradually when the Fe content x increased

from 0.09 to 0.15, but when x further increased to 0.21, Hci

decreased. Hci attained its peak value of 2276.6 kA/m with Fe

content x=0.15 at room temperature. For magnets with x=0.15, Br,

(BH)max and Hci reached 0.67 T, 81.2 kJ/m3 and 509.4 kA/m at 500

°C, respectively, showing good high temperature stability, which

could be used in high temperature applications.

NdFeB magnets; intergranular addition; magnetic

作者:莫文剑;张澜庭;刘琼珍;单爱党;吴建生;Komuro Matahiro;沈丽萍;
关键词:NdFeB magnets; intergranular addition; magnetic

properties; corrosion resistance; microstructure; rare earths
单位:School of Materials Science and Engineering  Shanghai Jiao

Tong University,School of Materials Science and Engineering

Shanghai Jiao Tong University,School Block neodymium magnet of Materials Science and

Engineering Shanghai Jiao Tong University,School of Materials

Science and Engineering Shanghai Jiao Tong University,School of

Materials Science and Engineering Shanghai Jiao Tong

University,Advanced Research Laboratory Hitachi Ltd. Hitachi-shi

Ibaraki-ken 319-1292 Japan,http://www.chinamagnets.biz/Neodymium/Block-neodymium-magnet.php Hitachi (China) Research & Development

Corporation Shanghai Branch,,Shanghai 200240 China,Shanghai

200240 China,Shanghai 200240 China,Shanghai 200240 China,Shanghai

200240 China,Shanghai 200020 China
摘要:Microstructure and corrosion resistance of sintered

Nd15Dy1.2Fe77Al0.8B6 and Nd22Fe71B7 magnets modified by

intergranular addi- tion of MgO and ZnO were investigated. Both

the remanence and sintering density of the magnets increased

slightly with intergranular addi- tions of MgO and ZnO. There was

a remarkable increase in coercivity of Nd22Fe71B7 after addition.

Besides, the effects on magnetic proper- ties and an improved

corrosion resistance were observed. Compared with the native

magnets without addition, corrosion potential of the magnets with

MgO and ZnO additives was more positive and the current density

in the anodic branch of the polarization curve was reduced.

Corrosion resistance resulting from autoclave testing (2×105 Pa

of steam pressure, 120 °C) showed that the corrosion rate of

NdFeB magnets reduced with the increase of additive amount.

Microstructure observation revealed that MgO and ZnO additives

were incorporated into the intergranular phases in the magnets.

With the introduction of MgO and ZnO, more intergranular phase

with high oxygen content was formed while keeping the volume

fraction of all the intergranular phases almost unchanged, which

may contribute to improved corrosion resistance. Furthermore,

addition of MgO and ZnO refined the grain size of Nd22Fe71B7.

strip casting technique; rare earth permanent magnet

作者:韩卫平;郭炳麟;喻晓军;祝景汉;程星华;
关键词:strip casting technique; rare earth permanent magnet

material; rare earth hydrogen storage alloy; columnar crystal
单位:Functional Material Division Advanced Technology & Materials

Co.,Ltd,Functional Material Division,Ball Neodymium Magnets Advanced Technology &

Materials Co.,Ltd,Functional Material Division,Advanced

Technology & Materials Co.,Ltd,Functional Material

Division,Advanced Technology & Materials Co.,Ltd,Functional

Material Division,Advanced Technology & Materials

Co.,Ltd,,Beijing 100081 China,Beijing 100081 China,Beijing 100081

China,Beijing 100081 China,Beijing 100081 China
摘要:The SC technique is now being applied widely in material

preparation, especially in rare earth functional materials in

virtue of its advanced process and high performance product. The

applications of SC technique in rare earth permanent magnet

alloys and hydrogen storage alloys http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php were analyzed integrative, on

the basis of summary of SC technique development in this paper.

The paper mainly includes development history of SC technology,

effect of SC technology on alloy microstructure, application of

SC technology in RE storage hydrogen alloy and sintered Nd-Fe-B

alloy, development of SC equipment and SC product industry. At

the same time, the paper points out the existing problem of SC

products.

nanocomposite; temperature coefficient; magnetic

作者:张士岩;徐晖;谭晓华;倪建森;董远达;
关键词:nanocomposite; temperature coefficient; magnetic

properties; Zr addition
单位:Institute of Material Science  Shanghai University,Institute

of Material Science Shanghai University,Institute of Material

Science Shanghai University,Institute of Neodymium Magnets Material Science

Shanghai University,Institute of Material Science Shanghai

University,,Shanghai 200072,China,Shanghai 200072,China,Shanghai

200072,China,Shanghai 200072,China,Shanghai 200072,China
摘要:The influence of Zr addition on magnetic properties and

temperature coefficient for nanocomposite Nd10Fe78.5-xCo5ZrxB6.5

(x=0～4) bonded magnets was investigated. It was found that the

room-temperature magnetic properties were remarkably improved

with Zr addition due to the grain refinement and increasing

volume fraction of the hard magnetic phase. The optimal magnetic

properties of Jr=0.689 T, iHc=769.4 kA·m-1 and (BH)max=84 kJ·m

-3 were obtained for 2.5% Zr http://www.999magnet.com/products/110-sintered-neodymium-magnets addition. The temperature

coefficient of remanence (α) increases slightly and the

temperature coefficient of coercivity (β) decreases obviously

with increasing Zr content for nanocomposite Nd10Fe78.5-

xCo5ZrxB6.5 (x=0～4) bonded magnets.

Application of Neural Networks PID Algorithm in Rotation and Location Control for the Crucible

Application of Neural Networks PID Algorithm in Rotation and Location Control for the Crucible

 A new method of controlling the rotation and location of the single crystal furnace crucible is present in the dissertation, which bases on the technology of single crystal silicon growth, and designs the hardware circuit according and program to the require. It respectively controls the rotation and location of the single crystal furnace by a piece of single-chip micyoco 80C196KC. The drive motor of the single crystal furnace crucible is the permanent magnetism direct-current servo motor, and the drive neodymium standard state of the motor adopts MOSFET which is as the master element in the control. There are many merits of the permanent magnet direct-current servo motor, such as the volume is small, the weight is light, the output power is big, the efficacy is high, the structure is simple, the initiating performance is good, operation is smooth, and it can control the speed in the extensive range. In the growth of the single crystal silicon, it adopts the signal of diameter and weight that are detected by the sensors of diameter and weight as the controlling data of diameter. The way can improve the accuracy of the diameter.Because the controlling object has the characters of nonlinearity, time-varying, time delay, the general PID controller is difficult to come to the exact controlling. It adopts the calculation of PWM space ratio by the combination of ANN and traditional PID algorithm, and then adjusting the output of the PWM of the single-chip computer, to realize the adjustment http://www.999magnet.com/products/112-neodymium-standard-state of armature voltage of the motor, and to control the rotation and location of the single crystal furnace crucible. The system can ensure the stability and robustness in the process of the crystal growth, and make the error of the diameter much smaller than the present standard +/-1 mm, it also can improve the quality of the crystal growth and the rate of finished products. 更多还原