比導磁率 的英文怎麼說
中文拼音 [bǐdǎocílǜ]
比導磁率
英文
specific permeability-
The bragg diffraction efficiency of gows in bismuth - doped yig film is caculated by considering the edge cut - off effect. the obtained theoretical curve is basically agreement with the experimental results. it is shown that the diffraction performance for mo bragg cells can be greatly increased by using an appropriately nonuniform bias field
2 .考慮到邊緣截止效應,論文中計算了靜磁正向體波對導波光的衍射效率,理論結果與實驗符合;從而表明,與均勻場情形相比,適當不均勻場可以大大提高磁光bragg器件的衍射效率。The stability of electric power system has been being focused for a long time toprevent a power system from losing synchronism after sudden fault , researchers have done much work and got many accomplishments this paper applied the direct feedback linearization ( dfl ) technique on the power system , a strong nonlinear system simulation results by matlab proved this method efficiency main works and results are as follows : this paper compared some existing methods in excitation control , fast valve control and coordinated control respectively, analyzed the developments and actuality of nonlinear control research in brief, illustrated why ransient stability could be greatly improved by using the fast valve control in chapter 3 , indicated the importance of coordinated control farther this paper introduced the inverse system theory, based on which , discussed the dfl theory, pointed out which had consistency with the inverse theory, expanded the dfl theory combined the idiographic model equations , made which adapt to the model of a single machine - infinite bus power system this paper referenced abundance articles and educed a set of equations , which could describe the dynamical process of excitation and fast valve control for synchronous generators in the equations , there were several very important parameters of power system - - rotor angle ( ) , rotor speed ( ) , generator q axis voltage ( eq ) , transient voltage ( e ' q ) , active power ( pe ) , mechanical input power ( pm ) , valve opening ( ) , generator terminal voltage ( vt ) , based on the model , nonlinear coordinated controller and terminal voltage optimal controller have been designed by using the expanded dfl theory and lq optimal control theory the simulation results showed that the controller could keep power system transiently stable under the effects of a symmetrical 3 - phase short circuit fault , which achieved better postfault regulation compared with another two routine methods , one is the proportion excitation controller and proportion fast valve controller, the other is the proportion excitation controller and the optimal fast valve controller, which could exert good performance when met 1ittle disturbance either
在介紹逆系統理論的基礎上,詳細介紹了dfl理論,通過比較闡明了dfl理論其本質是逆系統方法的一類,並結合具體課題推導出的模型方程將dfl理論進行了擴展,使之適應于電力系統這個強非線性對象。通過參考大量的書籍文獻推導出一套實用的可將大型汽輪發電機勵磁與汽門綜合起來進行控制的模型方程,此模型方程涵蓋了電力系統中特別引人注目的幾個量- -轉子角、轉子轉速、發電機q軸電勢eq 、暫態電勢e ' q 、有功功率pe 、機械功率pm 、汽門開度、機端電壓vt ,在此基礎上建立了實用的電力系統簡化的數學模型,並將擴展的dfl理論應用於此模型系統,結合線性二次型最優控制理論設計出大型汽輪發電機的非線性綜合控制器及機端電壓最優控制器,通過模擬實驗與採用常規的按電壓偏差進行調節的比例式勵磁控制器+汽門比例控制及採用常規的按電壓偏差進行調節的比例式勵磁調節器和基於二次型性能指標設計的最優快控汽門(考慮發電機的飽和因素)進行了對比,證實了採用此種控制器可以有效地提高電力系統的暫態穩定性,並且在電力系統遭受小干擾時同樣具有良好的調節性能。Relative temperature coefficient of initial permeability
初始磁導率比溫度系數Compared with three - level atomic system, the atomic coherence effects in four - level can lead to eit and eia, which depend on the intensity of control light and the relaxation of the fourth level
與三能級原子系統相比,四能級原子相干效應即可導致電磁感應透明的產生,也可產生電磁感應吸收現象,取決于控制光的強度和第四個能級衰變率的大小。By successful solution of non - linear magnetic fields and revision of the program, we can reach following conclusions : in the computation of nonlinear magnetic fields, if iteration method is used, under - relaxation is necessary when amending the permeability distribution in soft magnetic materials ; and when < wp = 5 > calculating the equivalent current density in permanent magnets, under - relaxation is not a necessity ; when searching for permeability values by interpolation method on the demagnetization curve of soft magnetic materials, if a fixed saturation point is set, around this point an abrupt change of permeability values will be obtained ; this sudden change may cause a little problem in the smoothness of magnetic field distribution ; because the magnetic circuits of microwave tubes are too complicated, in the author ' s view, to describe the working state of a magnet system, the working points of magnets can not do it properly but average energy production of magnets will serve ; as to indicate the quality of a magnet system design for microwave tubes, the efficiency of magnetic energy utilization will be a very good criterion
由此得出結論,在非線性磁場計算中:採用迭代法的情況下,在各迭代循環之間進行磁導率修正時,一個欠鬆弛迭代過程是必需的;對永磁體中的等效電流修正時可以不作欠鬆弛迭代;在純鐵的磁化曲線上指定某一個固定的磁感應強度為磁飽和值,會使得插值求出的磁導率在該磁飽和值附近有一突變,這一突變對計算結果中磁場分佈變化的光滑性稍有影響。在微波管磁系統設計中,由於微波管磁路比較復雜,作者認為磁體的工作點並不能很好地反映磁體的工作狀態,而採用平均磁能積為衡量磁體工作狀態的標準更加符合微波管磁系統的實際情況;要表示磁系統設計好壞的程度,則用磁能利用的效率為標準更好。B ) equivalent circuit method and finite element analysis ( fea ) to compute the static force are presented, the results obtained by each method are compared one with the other. c ) the results of dynamic simulation by means of the software, ansoft show the hlfm " s characteristics when the motor works in the special frequency and single stroke and the conditions used for position control. d ) the measured static thrust - displacement characteristics and the dynamic characteristics during starting show good correlation with the calculated results
在設計並製作了實驗樣機的基礎上所做的研究內容包括; ( 1 )分別用能量法和麥克斯韋張量法推導電磁力的計算公式,並討論他們的不同應用范圍; ( 2 )分別用等效磁路法和有限元法作直線力電機的靜特性分析,並比較分析它們的計算結果; ( 3 )用有限元模擬軟體做直線力電機動態特性的模擬,分別分析直線力電機的頻率特性、動子開合閘特性和開環位置控制的工作特性; ( 4 )做直線力電機的靜推力?位移特性實驗和動子開合閘的動態實驗,並將實驗結果與計算結果進行對比,實驗驗證了計算模型及計算方法的正確性。In order to improve the behavior of transformer protection that is incomplete at present in distinguishing magnetizing inrush current from fault current, the paper puts forward a kind of new principle of transformer differential protection after analyzing the characteristic of magnetizing inrush and active power consume of transformers. this protection uses differential protection based on positive sequence active power as a criterion to discriminate internal faults from magnetizing inrush, and ratio restraint differential current protection as a signal to touch off the protection
針對當前電力系統中變壓器保護由於勵磁涌流鑒別理論不完善而導致的誤動率相對較高的問題,論文在分析了變壓器勵磁涌流特性和有功損耗的基礎上,提出了用變壓器正序有功功率差動作為區別勵磁涌流和故障電流的判據,並以成熟的比率制動差流保護作為內外部故障判據的變壓器主保護。The x - ray diffraction, scanning electronic microscope and the squid were used to characterize the properties of the mgb2 core in mgb2 / fe tapes and wires. the effect of the proportion of mg, b and sic as well as the sintering parameters on the phase formation, microstructure and the critical current densities of mgb2 / fe tapes and wires was discussed in details. the results showed that the high purity of mgb2 core could be synthesized by both the traditional vacuum sintering and the sparking plasma sintering and the vacuum sintering environment restrained the oxidation of mg effectively
相對于傳統真空燒結, sps燒結方式成相速度快、樣品晶粒細小均勻、 mgb2超導芯緻密性好、晶間連接優良,因而sps燒結樣品的臨界電流密度明顯高於傳統真空燒結樣品,其中未摻雜的帶材樣品經過sps800 , 15分鐘燒結后,自場下的臨界電流密度jc值在10k時達到8 . 64 105a / cm2 ,而且隨著測量溫度和外加磁場的增加, sps燒結樣品的臨界電流密度下降率比傳統真空燒結樣品緩慢,在20k ,自場時為5 . 97 105a / cm2 , 20k , 3t時,臨界電流密度值仍大於104a / cm2 。Abstract : a two - pole axially - laminated anisotropic ( ala ) rotor reluctance motor, with a high saliency ratio, is de - veloped. based on it, the performance characte istics of the motors are investigated with open - loop operation. it is proposed that an intensive oscillation occurs at low speed, corresponding to the frequency supplied a little greater than the natural one of the system
文摘:研製了一臺高凸極比的兩極ala轉子磁阻同步電動機,實驗研究了電機的開環運行特性,研究結果表明電機開環運行時存在一個比較嚴重的低頻振蕩,這個振蕩發生在電機電源頻率略大於電機的自然頻率后的某一頻段,且會導致電機失去同步And then we used the armor plate to do the experiment, we found that the thin silicon steel board which poses high magnetism conductance rate is far better than the normal steel board
選擇鋼板材料作渦流加熱實驗時,發現具有高磁導率的薄硅鋼板的渦流熱效應明顯比普通鋼板好。We have investigated transport properties of electrons in magnetic quantum structures under an applied constant electric field. the transmission coefficient and current density have been calculated for electron tunneling through structures consisting of identical magnetic barriers and magnetic wells and structures consisting of unidentical magnetic barriers and magnetic wells. it is shown that the transmission coefficient of electrons in a wider nonresonance energy region is enhanced under an applied electric field. the resonance is suppressed for electron tunneling through double - barrier magnetic ( dbm ) structures arranged with identical magnetic barriers and magnetic wells. incomplete resonance at zero bias is changed to complete resonance at proper bias for electron tunneling through dbm structures arranged with different magnetic barriers and magnetic wells. the results also indicate that there exist negative conductivity and noticeable size effect in dbm structures
對磁量子結構中電子在外加恆定電場下的輸運性質進行了研究.分別計算了電子隧穿相同磁壘磁阱和不同磁壘磁阱構成的兩種磁量子結構的傳輸概率和電流密度.計算結果表明,在相當寬廣的非共振電子入射能區,外加電場下電子的傳輸概率比無電場時增加.對于電子隧穿相同磁壘磁阱構成的雙磁壘結構,共振減弱;對于電子隧穿不同磁壘磁阱構成的雙磁壘結構,無電場作用時的非完全共振在適當的偏置電壓下轉化為完全共振,這時的電子可實現理想的共振隧穿.研究同時表明,磁量子結構中存在著顯著的量子尺寸效應和負微分電導( 3 ) the saturation shear stresses vary as the relative permeability of the matrix fluids, the volume fraction of particles, and the square of the particles " saturation magnetization
磁流變液的飽和剪切屈服應力隨基液磁導率、磁性固體粒子濃度呈線性正比關系,隨磁性固體粒子的飽和磁化強度呈平方正比關系。( 2 ) the shear stresses vary as the relative permeability of the matrix fluids, the volume fraction of particles, and the square of the particles " magnetization. the shear stresses increase with the external magnetic field, but have saturation values
磁流變液的剪切應力隨基液磁導率、磁性固體粒子濃度呈線性正比關系,隨磁性固體粒子的磁化強度呈平方正比關系,隨著外加磁場的增大而迅速增大。The change of transformer ’ s output voltage with coupling coefficient is analyzed. the calculated formulas for parameters of air - core and part - magnetic - core pulse transformer are deduced based on electromagnetic theory. comparing with past formulas for calculated the parameters of the transformer, this formulas is more accurate to reckon the parameters of transformer
首先從理論上分析了提高耦合系數對變壓器輸出電壓的影響,推導了高功率帶繞式空芯和部分磁芯脈沖變壓器的電感及耦合系數的計算公式,並與已有的方法進行比較,經實驗驗證,本文推導的方法能夠較準確地計算帶繞式空芯脈沖變壓器的參數。Compared with traditional silicon steel, fe - 6. 5wt % si in theory is considered as an excellent property soft magnetism alloy. it has such excellent soft magnetism properties as higher permeability higher saturation magnetic induction near - zero magnetostriction and low core loss
Fe - 6 . 5wt si硅鋼是一種性能優異的軟磁合金,與傳統硅鋼材料相比,它具有高磁導率、高飽和磁感應強度、低磁致伸縮和低鐵損等更優異的性能。The following important work has been done : ( 1 ) some special problems of rate - bias laser gyro were analysed. the problems include modulation and demodulation of the output and algorithm of the attitude updates ; ( 2 ) the integrated navigation system with the fault tolerance property which equipped with many navigation equipments as sins, gps, dvs, ads, mg, vg is designed, and compared with that of ckf via simulations ; ( 3 ) the theories and methods of system level fault detection apply to federated filtering is investigated ; ( 4 ) the problem about using the fused information of sins based on rate - bias laser gyroscope / dynamical tune gyroscope to realize the component level hard fault interactions detection through a back - propagation neural network is discussed
主要研究工作有:研究了速率偏頻激光捷聯慣導的陀螺測量信號的解調演算法;設計了在速率偏頻激光捷聯慣導、 gps 、多普勒雷達、大氣數據系統、磁航向儀及垂直陀螺配備條件下聯邦濾波組合導航系統,對聯邦濾波器和集中濾波器的性能做了模擬對比分析;研究了適用於聯邦濾波器的系統級故障理論和方法;探討了利用速率偏頻激光捷聯慣導撓性捷聯慣導陀螺的混合測量信息,通過神經網路實現硬故障交互檢測的方法。Abstract : this paper proposes an self - adaptive speed - accommodating control circuit, which can get the speed - error, and can test the change of frequency of feedback signals of the single phase ac tacho generator through self comparing and automatically corrects the speed
文摘:文章介紹了通過自比較來檢測錄音機主導軸單相永磁交流測速發電機反饋信號的頻率變化,從而獲得速度誤差,並自動校正轉速的一種自適應速度調節控制電路。Starting with automation system, this paper, firstly, outlines the status of sensor lying in automation field and its developing state, shows the superiority about eddy current test by comparing it with the other nondestructive tests, expatiates the modern developing state about eddy current technology both here and there, shows the vista about eddy current test in our country and the background of the subject about the test for the width and thickness of stripe in the in - wall of cylinder after laser thermal treatment. secondly, beginning with maxwell equation in electromagnetic field theory and combining with some electromagnetic phenomena in real life, this paper explains qualitatively the operating principle about eddy current technology and the test theory for multi - parameter test with multi - frequency by math illation and gives some applying occasions about it
通過同其它幾種無損檢測技術的比較,給出了電渦流技術的優越性,闡述了國內外電渦流技術的發展現狀,展望了我國電渦流技術發展的未來,給出了汽缸內壁激光熱處理條紋厚度與寬度的檢測這個課題的背景;然後從電磁場理論中的麥克斯韋方程出發,通過一系列的數學嚴密推導,並結合現實生活中的一些電磁現象,定性地解釋了電渦流技術的原理,以及電渦流傳感器多頻率多參數的檢測原理,給出了電渦流技術的部分應用場合,以及電渦流檢測的等效電路。The mode competition is much improved. it may operated with a large electron beam radius, that means decreasing the space charge effects compared with a smaller radius beam with the same current, hence the rbwo may operated with a low axial guide magnetic field. besides, the rbwo with a sinusoidal corrugated coaxial structure is very easy to manufacture
波紋內導體rbwo具有一些突出優點:同軸結構中內導體的存在使系統的截止頻率顯著升高,使得系統尺寸可比普通波紋波導慢波系統大;具有很大的抑制模式競爭的能力和很高的功率容量;可以採用大半徑電子注,在工作電流不變的情況下空間電荷效應大幅度降低,因而可以工作在低磁場狀態;此種慢波結構內導體上的波紋易於加工。3 in si units, the ratio between the magnetic flux density b and the magnetic force h defines the permeability
在國際單位制中,磁感應強度b與磁場強度h之比被稱為導磁率。分享友人