磁測基點 的英文怎麼說
中文拼音 [cícèjīdiǎn]
磁測基點
英文
magnetic base station-
Depend on the comprehensive analysis and study of the structure, principle, and exterior characteristic of the motor, through the methods of system modeling and digital simulation analysis, two kind of control device that work for the low voltage ( lvdc ) and the high voltage ( hvdc ) in avigation are researched respectively. point to the control technique of close - loop speed stabilization at a limited adjustment speed range, we bring out the close - loop speed control method that using the rotor position sensor indirectly measure the speed of the motor
在全面分析了稀土永磁無刷直流電動機的結構特點、工作原理、運行方式以及外部特性的基礎上,通過系統建模和數字模擬分析,分別針對航空低壓直流( lvdc )和高壓直流( hvdc )兩種電動機構用永磁無刷電動機,在小范圍轉速連續調節下的閉環穩速控制技術進行了詳細理論研究,提出了利用轉子位置傳感器信號間接測量電機轉速進行電機轉速閉環穩速控制的策略。Fourthly, according with the analyzing of flow measurement, we research the main problems needed to be solve in the process of measurement, such as analysis and measurement of the internal resistance, selection of excitation frequency, stable signal datum mark and restraining common mode interference, restraining for serial mode interference and working frequency interference ; transporting and shielding the flow signal, constant current excitation and magnetic field equalizing, flow measuring
第四,根據對流量測量問題分析的,深入研究了設計過程中需要解決的主要問題。如內阻分析與測量;勵磁頻率的選擇;穩定信號基準點與抑制共模干擾;串模干擾與工頻干擾抑制;流量信號傳輸與屏蔽;恆流勵磁與磁場補償;流量測量點的選擇等。Magnetoelectricity gear method is a general torsional oscillation measurement method. it has disadvantages on less measure point and improved - needed dynamic characteristic. in the paper a new method of measuring torsional oscillation of the turbine - generator shaft was proposed on the basis of high speed ccd ( charge coupled device ) photography
現行的扭振測量方法以磁電式齒輪測量法為主,這種方法存在測點少,動態特性有待提高的缺點,就此本文提出了一種基於高速ccd ( chargecoupleddevice )攝像技術的汽輪發電機組軸系扭振測量的新方法。The algorithm principle, hardware design and software design of the scheme are proposed and experimentally demonstrated ; the main contents of this thesis are as follows : firstly, we study the principle of the fiber optic weak magnetic sensor based on magnetostrictive effect. after analyzing the characters of the magnetic field sensing signals, we know that the magnetic field sensing signals ’ fundamental component is proportional to input dc magnetic field
敘述了該方案的原理、軟硬體設計過程,並通過實驗進行了驗證,本文主要內容如下:首先,研究了基於磁致伸縮效應的光纖微弱磁場傳感器傳感原理以及輸出信號的特徵,分析得出在干涉儀處于正交工作點時,傳感器輸出信號的基頻分量與被測直流磁場成正比關系。In the thesis, a signal processing scheme of polarization - insensitive fiber optic michelson interferometric magnetic sensor is described : making the interferometer work near the quadrature with closed loop controlling working point method, the fundamental frequency component of the magnetic field sensing signals can be detected to measure the input direct current ( dc ) magnetic field by phase sensitive demodulation
本文主要介紹了偏振無關光纖michelson干涉型微弱磁場傳感器信號處理的方案:通過閉環控制工作點演算法使干涉儀工作在正交工作點處,再利用相敏檢波演算法提取傳感器輸出信號的基頻分量,以測量直流磁場的大小。In order to utilize the magnetic anomaly information obtained by high - precision aeromagnetic survey more effectively, this paper, based on the reliable proof of the existence of weak magnetic anomalies in middle and high mountain areas and combined with characteristics of middle and high mountain areas, has advanced an improved nonlinear filtering method and described its effect in practical application
為了更有效地利用高精度航空磁法測量得到的磁異常信息,在充分論證中高山區弱磁異常存在的可靠性基礎上,結合中高山地區特點,提出了改進的非線性濾波方法,並給出其實際應用效果。The resistivity of the films drops compared with the as - grown films, but the temperature of maximum magnetoresistance reaches 287k, very close to the room temperature. therefore it is not only an important improvement to fabricate the cmr bolometer which can work near room temperature, but also a prospective research for other applications such as magnetic - sensors, spintronics devices and infrared detectors
同時,退火后薄膜的電阻率明顯下降,外加5t磁場時,最大磁電阻率溫度點上升到287k ,接近於室溫,這不僅為製作室溫超巨磁電阻測輻射熱儀打下了堅實的基礎,也為其它許多器件的應用提供了可能。For parameter a, there is a close relationship exist between a ( 9, sr ) in two different radar incident angle that can be expressed as : with considering the effects of soil texture, we get the final expression of the inversion model : where mv ( t1 ), mv ( t2 ) is volumetric soil moisture content in two different temp, c, d is soil type related parameters, and v ( t1 ), s ( t2 ) is coresponding bare soil radar backscattering coefficients. inversion results show that for the c band hh polarized radarsat scansar data with a range of incidence angle from 20 to 40, the soil moisture change value can be derived with an acceptable accuracy using the above model. the temporal and spatial soil moisture change patterns are associated with rainfall and vegetation cover, as well as the soil hydraulic characteristics
利用最新發展的電磁波散射模型研究了不同植被覆蓋地表雷達波對地表土壤水分的敏感性,建立了半經驗植被雷達後向散射模型; 2 ) .研究發現在農作物等矮小植被覆蓋地表,植被層直接後向散射與植被類型相關,且在植被生長期,雷達後向散射系數對植被含水量的敏感性要高於對植被高度變化的敏感性; 3 ) .解決了單參數雷達地表土壤水分反演問題中,雷達入射角和地表粗糙度的影響這一難點問題; 4 ) .利用土壤介電模型校正了不同土壤類型對反演地表土壤體積含水量的影響; 5 ) .在以上成果基礎上,建立了完整的單參數雷達地表土壤水分變化探測反演演算法,經地表驗證,模型反演地表土壤水分變化值的精度為rmse = 0This paper systematically discussed the fundamental, characteristics, research status and equipment of microwave sintering, and introduced the preparation and development of sintered ndfeb magnets, on the basis of which the effects of the parameters on the heating rate and sintering temperature were investigated. and by means of optical metallurgical analysis, x - ray diffraction analysis and the measurement of density and magnetic properties, the paper compared the properties and technology of ndfeb magnets sintered in microwave magnetic field with that of magnets sintered in conventional heating process
本文系統論述了微波燒結基本原理、特點、研究現狀和燒結設備,介紹了燒結ndfeb制備工藝和發展,在此基礎上研究了微波磁場燒結ndfeb永磁材料過程中各因素對升溫速率、燒結溫度的影響,並通過金相顯微分析、 x射線衍射分析、密度及磁性能測試等手段,將微波磁場燒結的ndfeb磁體與常規燒結的磁體進行了工藝與性能的對比分析。The model of fujian power grid and models of generators, excitation systems, governor systems and loads are established, the tested excitation system models of large hydro and thermal units, the model of wind turbine are established as well in this paper with pss / e, a new software imported from pti of u. s. a. recently. some key points are proposed on data convertion from psasp and bpa to pss / e. the transient and dynamic characteristics between separate excitation system and transformer - fed excitation ( self excitation ) system are compared with pss / e
本文完成了pss e的福建省電力系統的基本框架以及發電機、勵磁系統、調速系統、負荷的數學模型和參數,實現了大型水、火電廠發電機組勵磁系統實測模型和風電機組的pss e建模,提出了pss e與bpa 、 psasp數據互轉的部分要點,比較了福建電力系統現有大型水、火電廠發電機組它勵與自並勵勵磁方式的動態和暫態性能的差別。Aim at the dtc ' s blemish mentioned above and the direction of dtc technique development, the dissertation put great emphasis on the work as follows, with an eye to exalt dtc system function : ( 1 ) a new speed - flux observer of an induction motor is proposed to enhance the accuracy of flux observing, which is an adaptive closed - loop flux observer and different from the traditions. a new adaptive speed - observation - way is deduced out according to the popov ' s stability theories ; ( 2 ) to improve the performance of dtc at low speed operation, we have to exalt the accuracy of the stator flux estimation and a new way of bp neural network based on extended pidbp algorithm is given to estimate and tune the stator resistance of an induction motor to increase the accuracy of the stator flux estimation ; ( 3 ) digital signal processor is adopted to realize digital control. an device of direct torque control system is designed for experiment using tms320lf2407 chip produced by ti company ; ( 4 ) bring up a distributed direct torque control system based on sercos bus, sercos stand for serial real time communication system agreement which is most in keeping with synchronous with moderate motor control ; ( 5 ) the basic design frame of the hardware and software of the whole control system is given here and some concrete problem in the experiments is described here in detail
針對上面提到的直接轉矩控制的缺陷和未來直接轉矩控制技術發展方向,本論文重點做了以下幾個方面的工作,目的在於提高dtc系統的綜合性能: ( 1 )提出一種新型的速度磁鏈觀測器,新型的速度磁鏈觀測器採用自適應閉環磁鏈觀測器代替傳統的積分器從而提高磁鏈觀測的精度,並且根據popov超穩定性理論推導出轉速的新型自適應收斂律; ( 2 )改善系統的低速運行性能,主要從提高低速時對定子磁鏈的估計精度入手,提出了一種提高定子磁鏈觀測精度的新思路? ?利用基於bp網路增廣pidbp學習演算法來實時在線地修正定子電阻參數; ( 3 )採用數字信號處理器dsp實現系統全數字化硬體控制,結合ti公司生產的tms320lf2407晶元,設計了直接轉矩控制系統的實驗裝置; ( 4 )提出了基於sercos總線網路化分散式的直接轉矩控制系統, sercos ( serialrealtimecommunicationsystem )是目前最適合同步和協調控制的串列實時通信協議; ( 5 )基本勾勒出整個控制系統的硬體和軟體設計基本框架,詳細描述一些實驗中的具體的細節問題。In this dissertation, the principle of fem in em was discussed, then the pulse radar and three - layered pavements were analyzed with 20 - noded and 4 - noded isoparametric elements respectively. then, corresponding fem programs are compiled in fortran90. so a forward model was built up to describe the transmitting of electromagnetic in the radar and pavements, according to the system identification method
針對上述情況,本文系統闡述了電磁場有限單元法的基本原理,然後採用二十節點、四節點等參單元分別對pulse雷達實體及三層路面系統進行了靜態場和時變場的有限元分析,初步建立了電磁波在三層路面中傳播的正演模型,同實測波形相比,模擬效果較好,並用fortran90語言編制了相應的三維、二維有限元程序,具有較好的可讀性和可移植性。Using the microwave selective heating property for materials, by setup equivalent equation, and first time inducing the electromagnetic field perturbation theory to the design of heating materials for substrate in mpcvd, three temperature distribution modes were established, including temperature distribution comprehensive mode of inhomogeneous plasma, temperature distribution composite mode of composite substrate materials, temperature distribution perturbation mode of composite materials, which ii provided an whole new technology route to the design of substrate heating system in mpcvd and guided the preparation of heating materials for substrate. and then the heating materials for substrate were designed and optimized to obtain large area homogeneous temperature distribution even larger than substrate holder ' s diameter. as an important part, this thesis researched the nucleation and growth of diamond films in mpcvd, systematically researched the effects of substrate pretreatment, methane concentration, deposition pressure and substrate temperature etc experimental technologic parameters on diamond films " quality on ( 100 ) single crystal silicon substrate in the process of mpcvd, characterized the films qualities in laser raman spectra ( raman ), x - ray diffraction ( xrd ), scanning electron microscopy ( sem ), infrared transmission spectra ( ir ), atomic force microscopy ( afm ), determined the optimum parameters for mpcvd high quality diamond in the mpcvd - 4 mode system
該系統可通過沉積參數的精確控制,以控制沉積過程,減少金剛石膜生長過程中的缺陷,並採用光纖光譜儀檢測分析等離子體的可見光光譜以監測微波等離體化學氣相沉積過程;利用微波對材料的選擇加熱特性,通過構造等效方程,並首次將電磁場攝動理論引入到mpcvd的基片加熱材料的設計中,建立了非均勻等離子體溫度場綜合模型、復合介質基片材料的復合溫度場模型及復合介質材料溫度場攝動模型,為mpcvd的基片加熱系統設計提供了一條全新的技術路線以指導基片加熱材料的制備,並對基片加熱材料進行了設計和優選,以獲取大面積均勻的溫度場區,甚至獲得大於基片臺尺寸的均勻溫度區;作為研究重點之一,開展了微波等離體化學氣相沉積金剛石的成核與生長研究,系統地研究了在( 100 )單晶硅基片上mpcvd沉積金剛石膜的實驗過程中,基片預處理、甲烷濃度、沉積氣壓、基體溫度等不同實驗工藝參數對金剛石薄膜質量的影響,分別用raman光譜、 x射線衍射( xrd ) 、掃描電鏡( sem ) 、紅外透射光譜( ir ) 、原子力顯微鏡( afm )對薄膜進行了表徵,確立了該系統上mpcvd金剛石膜的最佳的實驗工藝參數。On the basis of the research efforts of magnetic polymer nanocomposite at home and abroad in recent years, the preparation methods of magnetic polymer nanocomposite were reviewed in this article, the latest research advanced in magnetic polymer nanocomposite with core - shell structure and sandwich structure were also reviewed in detail, and also the applications in determinating microbe and organism in water determination were summarized
在總結國內外有關磁性高分子微球研究成果的基礎上,介紹了納米磁性高分子復合微球的制備方法,重點闡述了核殼式結構和三明治式結構納米磁性高分子復合微球制備的最新研究進展,概述了磁性高分子復合微球在檢測水中微生物和有機物的應用。Using high - resolution t1 - weighted magnetic resonance imaging and voxel - based morphometry, we examined a population of 133 healthy adults ( women, 73 ; men, 60 ; age range, 29 - 80 years ) focusing on differential aging between men and women ( i. e., interaction of age and gender )
利用高解析度的t1加權核磁共振影像和三維象素為基礎的形態測定法,我們研究了133位健康成年人( 73位女性; 60位男子;年齡范圍29 - 80歲) ,重點比較了不同年齡男子和女性的差別。In the process of mt depth measurement, frequencies with 40 numbers are basically used at present
摘要在大地電磁測深中,目前基本上使用40個頻率點的數據。Based on extensively gathering and sysmatically analyzing much geophysics, sedimentary, structure and petrological materials in research field and taking two field geological explorations from south to north in western odors basin margin, the paper studied large numbers of seismic sections and newly - finished profiles in former seismic blanked area of western margin as well as up - to - date gravity and magmatic fruits, put views on the regional geotectonic background and basin - mountain coupling and made through research on the structure features and attribute together with the result of fission track testing
筆者廣泛收集和系統分析了研究區大量的地球物理、沉積、構造和巖石學等資料,對盆地西緣自南而北進行了兩次野外地質實際調查,在此基礎上,重點研究了大量地震剖面和在西緣地震勘探空白區新完成的地震剖面及新近重磁電研究成果,結合裂變徑跡等測試分析資料,從區域地球動力學背景和盆山耦合的思路入手,對鄂爾多斯盆地西緣的構造特徵及其屬性進行了詳細解剖。Temperature measurement techniques for microfluids in capillary and microfluidic systems are reviewed, including exterior contact methods, fluid physical - parameter - based methods, thermo - sensitive marker methods, nmr and raman spectrometric methods, and laser - based interface measurement technique
摘要綜述了近年來應用於毛細管和微流控系統中的各種微流體測溫技術,包括外部接觸測溫、依據液體物理參數變化測溫、基於熱敏物質測溫、核磁共振和拉曼光譜測溫以及基於激光的界面測溫,並對各種測量方法和優缺點進行了討論。Firstly, this paper introduces the asynchronous motor model, and compares it with the dc motor ’ s. then the paper studies the principle of vector control, and proposes an improved current model of rotor flux observer. this paper also studies the three - level inverter ’ s topology, working principle, the neutral - potential unbalance mechanism and its controlling strategy. the paper especially studies the svpwm in details. the interface between the vector control and the three - level inverter is studied in details, including the generation of reference voltage vector, its judging of the sector and triangular regions, and the working mechanism after it sent into three - level inverter. when synthesizing the reference voltage vector, select the vector which only includes p and o states as the starting vector, thus eliminate the vector shift problem when sector changes. this paper fully takes advantages of the powerful functions of matlab / simulink to set up the simulation model. this construction is very explicit. the simulation results verify the inverter voltage output is correct, the rotor flux is steady, the asynchronous motor ’ s dynamic and steady state performances and speed modulation are excellent
本文首先介紹了異步電機的數學模型,在此基礎上將異步電機的數學模型與直流電機的數學模型進行了比較;然後介紹了矢量控制的基本原理,採用了一種改進的轉子磁鏈電流型觀測模型;對三電平逆變器的電路拓撲、工作原理、中點電位不平衡的機理及控制方法進行了介紹,詳細分析了空間矢量脈寬調制策略。本文對異步電機的矢量控制與三電平逆變器之間的介面進行了詳細的研究,包括:參考電壓矢量的形成、所落扇區與具體小三角形區域的判斷、送入逆變器之後的工作機理。在參考電壓矢量的合成時,選擇只包含p 、 o狀態的空間電壓矢量作為起始矢量,解決了扇區切換時的矢量突變問題。After studying a lot of documents, we present a speed - estimating method for direct torque control system. this method is based on the theory of dtc, but it takes advantage of the convenient of both the theory of dtc and the theory of foc. we need only to sample the stator ' s current to estimate the speed of the rotor, at the same time the integration of the voltage is avoided
在研究大量文獻的基礎上提出了一種適用於交流電機dtc控制系統的轉速計算方法,該方法以dtc控制為中心,結合dtc和定子磁場定向和轉子磁場定向各自的特點,綜合利用各自的有利之處,只需測量定子電流,避免了對電壓積分,思路清晰,計算簡單。分享友人