電流變換系數 的英文怎麼說

中文拼音 [diànliúbiànhuànxìshǔ]
電流變換系數 英文
current ratio
  • 電 : Ⅰ名詞1 （有電荷存在和電荷變化的現象） electricity 2 （電報） telegram; cable Ⅱ動詞1 （觸電） give...
  • 流 : Ⅰ動1 （液體移動; 流動） flow 2 （移動不定） drift; move; wander 3 （流傳; 傳播） spread 4 （向壞...
  • 換 : 動詞1. （給人東西同時從他那裡取得別的東西） exchange; barter; trade 2. （變換; 更換） change 3. （兌換） exchange; cash
  • 系 : 系動詞（打結; 扣） tie; fasten; do up; button up
  • 數 : 數副詞（屢次） frequently; repeatedly
  • 電流 : current; galvanic current; electric current; electricity; current flow電流保護裝置 current protec...
  • 系數 : [數學] coefficient; ratio; modulus; quotient; factor
  1. According to the system technology require, adopting singlechip realize open loop digital control of hdclsm ; using v / f conversion and complex key - control method realize digital setting of system parameter, such as velocity ; using micro - stepping control insure the motor running more smoothly ; adopting debasing speed control method to eliminate the mechanical impact of distance termination effectively ; at the same time, analyzing main power circuits drive circuit and protect circuit of system, completing hardware design and facture and software programming and debugging ; at last, making a whole test in hybrid rotary step motor. the experiment result indicates that this control system reaches the qualities required and run smoothly also

    根據系統技術要求，採用單片機實現了混合式直流直線步進電動機的開環數字控制；利用v f變換和復合鍵控方法實現了系統轉速等參數的數字設定；利用細分控制技術保證了電機運行的平穩性，並進行了波形分析和理論研究；採用單片機軟體降速控制策略解決直線步進電機行程末端的機械沖擊問題；同時對主功率電路、驅動電路和系統保護電路進行了分析，完成了硬體設計、製作和軟體編程、調試，最後在混合式旋轉步進電動機上進行了全面測試。
  2. Monitor apparatus can measure valid value of three phase voltage and current, power factor, three phase disequilibrium, instant flecker of short time and harmonic without twenty, degree and harmonic distortion total. the paper are laid on the following. ( 1 ) master plan and function of circuit, ( 2 ) hardware design including circuit and principle of a / d conversion, phase lock, liquid crystal display and keystroke and so on, ( 3 ) design of system software including digital filtering, fft, a / d conversion and monitor interface of pc, ( 4 ) system test

    監測儀能夠完成包括三相電壓、三相電流的有效值、功率因數、三相不平衡、電壓短期閃變、以及20次內的諧波、諧波相位、諧波失真總量等的測量。論文重點介紹了以下幾部分： （ 1 ）電路的總體設計和功能； （ 2 ）硬體設計，包括a d轉換、鎖相環、液晶顯示和按鍵輸入等原理和電路。 （ 3 ）系統軟體設計，包括a d轉換、 fft 、數字濾波等程序的原理和演算法以及上位機監控界面的設計； （ 4 ）系統測試。
  3. Firstly, in spherical coordinate system, the sovp formulation for the time - harmonic electromagnetic fields of the current dipole in conductive infinite - space is derived, using reciprocity theorem and transforming relations between special functions. then, selecting appropriate coordinate system, using superposition principle, the boundary - value problem of modified magnetic vector potential on the problem of a time - harmonic current dipole in spherical conductor is solved and analytical solution is obtained. finally, by means of the addition formulas of legendre polynomial and spherical harmonics function of degree n and order 1, the analytical solution in spherical coordinate system specially located is transformed into that in spherical coordinate system arbitrarily located

    首先利用特殊函數間的轉化關系和互易定理推導得到了無限大導體空間中球坐標下時諧電流元電磁場的二階矢量位形式：然後利用疊加原理，選擇合適坐標系，求解了導體球中時諧電流元的修正磁矢量位邊值問題，得到了問題的解析解；最後依據不同坐標系下電磁場解的轉化原理，藉助勒讓德多項式和n次1階球諧函數的加法公式，將坐標系特殊安放時的電磁場解析解變換到坐標系一般安放時的解析解，給出了球內電場和球外磁場的並矢格林函數。
  4. During the period of measurement, the transduction circuits transform the differential pressures, the absolute pressures and the temperatures received by the sensors into the voltage signals, and then, the voltage signals are transformed into digital signals by the a / d convertor. the mcu processes these digital signals and calculates the cumulation of the flow. finally the totalizers contact with the pc by rs - 485 bus to form a distributed measuring network

    在測量過程中，系統以流量計節流所獲得的差壓信號作為主信號、絕壓和溫度信號作為補償信號進行流量積算，這三種信號分別由相應傳感器感知后，經各自的物理信號測量電路轉換為電信號，再由a / d轉換模塊轉變為數字量，交微控制器進行處理、積算。
  5. At present, the typic harmful current detection methods are the fast fourier transform algorithm in frequency domain and methods based on the instantaneous reactive power theory, these methods all require some transform and quick, real - time calculating, so high precision analog multipliers or high speed dsp chip with fast a / d are needed, this results in complex circuit and high cost ， which have restricted the development of apf

    目前畸變電流檢測常用的方法有頻域法的fft和基於瞬時無功理論的畸變電流檢測法。這些方法均有一定的變換，需要快速、實時運算，因此必須使用高速的數字微處理器和高性能a / d轉換器，這必將大大提高系統成本，使得電路結構復雜，在一定程度上限制了有源濾波器的發展。
  6. Eddy - current sensor conversion circuit consist amplification circuit, band - pass filter circuit, demodulation circuit, differentiation phase and data sampling circuit. these circuits are used to convert the test signal of eddy - current sensor to discrete signal tend to process. the microprocessor system that formed of dsp chip is used to data fitting of test system, data displaying and data communicating with personal computer, etc. the interference questions of hardware design and the measure of eliminating interference signal in the subject are introduced in the last of this chapter

    硬體電路的設計主要分三大部分來實現：激勵源電路部分，由分頻電路和頻率合成電路組成，產生頻率穩定的激勵信號以確保檢測任務的正常進行；傳感器變換電路部分，由放大電路、濾波電路、檢波電路、鑒相電路和數據採集電路組成，主要將電渦流傳感器檢測線圈檢測到的信號變換成只含有被測信息的離散信號，易於后續電路處理；由dsp晶元構成的微處理系統，主要完成檢測系統的數據擬合、顯示及與主機通信等功能。
  7. A novel parallel - serial type cttfc ( combined two - transistor forward converter ) with coupled inductor is present in this paper, and the performance of three parallel - serial type cttfcs is studied and compared. the performance of cttfc with coupled inductor is similar to the other two cttfcs while coupling coefficient is less than one and the converter working ccm ( continuous current mode ), and input - to - output voltage gain increase one times while coupling coefficient is one

    本文提出了一種耦合電感並?串型雙管正激組合變換器，並對三種並?串型組合變換器的特性作了比較：耦合系數小於1且耦合線圈電流連續時，三種並?串型組合變換器特性相類似：耦合系數為1時，組合變換器輸入輸出電壓增益增大一倍。
  8. Three parallel - parallel type cttfcs is studied and compared in this paper. the performance of the cttfc with coupled inductor is similar to that with sharing freewheeling diode while coupling coefficient is one, and similar to that with sharing output capcitor while coupling coefficient is less than one and the converter working ccm

    揭示了耦合電感並?並型雙管正激組合變換器與其餘兩種並?並型組合變換器的關系：耦合系數為1時，具有與共用續流管組合變換器相類似的特性；耦合系數小於1且耦合線圈電流連續時，具有與共用輸出濾波容組合變換器相一致的特性。
  9. The second chapter simply introduces the development of alternate asynchronous inverter technology and retrospects some types of energy - saving systems for hydraulic elevators. then the working principles of the project are discussed and analyzed at four different working status, i. e. light load upwards, heavy load upwards, light load downwards and heavy load downwards. and the chapter focus on the introduction of structure design of pump station, calculation and type selection of pump / motor reversible units, research on oil leakage principles of accumulator circuit, design of accumulator - pump / motor pressure - energy transformer and integrated valve blocks, etc. the last but not the least, the electrical wiring of vector inverter control cabin and design of computer control and data acquisition system are introduced

    論文第二章首先簡單介紹了交流異步電動機變頻調速技術的發展概況，在回顧電梯液壓控制系統節能技術的基礎上，介紹了本課題研製的「採用蓄能器的液壓電梯變頻節能控制系統研究」的基本原理，分析了動力系統在電梯轎廂輕載上下行、重載上下行等四種典型工況下的基本工作狀態和工作方式；詳細地介紹了本課題節能系統液壓動力泵站的結構設計和參數設計，重點研究了液壓動力泵站的結構設計、液壓泵馬達可逆性問題及其選型設計計算、蓄能器迴路泄漏油損失機理的研究及其補償裝置的設計、蓄能器-泵馬達壓力能量轉換裝置的設計、多功能集成控制閥組的設計等內容；最後簡單介紹了本課題矢量控制變頻控制櫃的外部附件電氣接線、計算機控制及數據採集系統的硬體設計等內容。
  10. There are five parts are as follows : in part one, the concept of switching function is introduced first to establish the nonlinear mathematical model of the induction motor variable frequency speed adjustment system which is fed by a sine pulse width modulated ( spwm ) inverter and takes the effect of the main magnetic circuit saturation into consideration, then the low frequency oscillation of the system is simulated according to the model. next, from the view point of energy conversion of the inverter - induction system, a criterion for the low frequency oscillation is proposed to determine whether the system is in low frequency oscillation which is judged by whether the interval of the negative current component of the inverter input current is more than 1 / fc ( fc is the carrier wave frequency of the inverter ) or not

    首先引入開關函數概念，建立了正弦脈寬調制（ spwm ）逆變器供電異步電動機，考慮主磁路飽和時的變頻調速系統整體數學模型，模擬系統的低頻振蕩；其次從逆變器-異步電動機系統能量轉換角度出發，提出通過檢測逆變器輸入電流中負電流的間隔時間是否大於1 / f _ c （ f _ c為逆變器載波頻率）來判定系統是否出現低頻振蕩；最後的實驗結果驗證了系統低頻振蕩建模和判據的實用性和正確性。
  11. The test instruments based on this method are highly precise, but costly. the author develops a grounding measurement system of substations based on the virtual instruments, which uses labview as the development software and adopts the small electric current method. the fft method is used to process the measurement data, which can decrease the measurement error

    本文作者研製了基於虛擬儀器的變電站接地網接地測量系統，該系統以labview為軟體開發平臺，採用小電流測試法，並利用快速傅立葉變換方法對測試信號進行數字濾波處理，提高了該系統的信噪比。
  12. According to the request of this subject, we have developed the system hardware and software for the slave device and the inspection software running on the pc. in this paper all of the followings is illustrated detailedly, such as the research on the principles of measurement and its realization, three means of water - level measurement that are separately based on photo electricity coder, pressure sensor and potentiometer ; selection of the microchip, we choose an advanced integrated soc ( system on chip ) microchip c8051f021 as the main controller ; realization of signal sampling, processing and its conversion in the mcu ; application of high precision 16 bits adc cmos chip - - ad7705 in our system, designing its interface with the microchip and relevant program ; using a trickle charge timekeeping chip ds1302 in the system which can provide time norm and designing of its i / o interface and program ; additionally, a 4 ~ 20ma current output channel to provide system check - up using ad421. in the system, ad421, ad7705 and the microchip compose spi bus ; to communicate with the master pc, here we use two ways which are separately rs232 and rs485 ; moreover, there are alarm unit, keyboard unit, power supply inspection unit and voltage norm providing unit in the system

    針對研製任務的要求，課題期間研製了下位機系統硬體和軟體，開發了上位機監控軟體，其中所作的具體工作包括：測量原理的研究和在系統中的實現，在本次設計中用三種方法來進行水位測量，分別是旋轉編碼器法、液位壓力傳感器法和可變電阻器法；主控晶元的選擇，我們選用了高集成度的混合信號系統級晶元c8051f021 ；實現了信號的採集和處理，包括信號的轉換和在單片機內的運算；高集成度16位模數轉換晶元ad7705在系統中的應用，我們完成了它與單片機的介面設計及程序編制任務；精確時鐘晶元ds1302在系統中的應用，在此，我們實現了用單片機的i o口與ds1302的連接和在軟體中對時序的模擬，該晶元的應用給整臺儀器提供了時間基準，方便了儀器的使用；另外，針對研製任務的要求，還給系統加上了一路4 20ma模擬信號電流環的輸出電路來提供系統監測，該部分的實現是通過採用ad421晶元來完成的，本設計中完成了ad421與單片機的spi介面任務，協調了它與ad7705晶元和單片機共同構成的spi總線系統的關系，並完成了程序設計；與上位機的通信介面設計，該部分通過兩種方法實現： rs232通信方式和rs485通信方式；系統設計方面還包括報警電路設計、操作鍵盤設計、電源監控電路設計、電壓基準電路的設計。
  13. The pulse - width modulated ( pwm ) is the key technologyto acquire the high power factor. the document presents the principle of three - phase pwm, then analyzes and compares the several maturely control methods for pwm

    本文將交流電機理論中空間坐標系旋轉變換理論引入到pwm整流器的分析中來，建立了三相pwm整流器的統一的數學模型。
  14. This thesis chooses b spline wavelet that adapts to the analysis of power system signal, and uses the wavelet transformer to analyze the magnetizing inrush current and inner fault current. a transformer microcomputer protection was designed in this thesis, and in the base of intermission angle principle, a new criterion was established, which pierces through the traditional method with accurate measurement of intermission angle, but analyses the wave by wavelet transform. this criterion is lower in hardware, so it will be realized in the existing hardware

    本文選擇適合電力系統信號分析的b樣條函數作為母小波，對勵磁涌流和內部故障電流進行小波分析，並設計微機型變壓器保護基本配置，在以往間斷角原理鑒別勵磁涌流的基礎上，突破傳統精確測量勵磁涌流間斷角的方法，直接對信號小波變換后的波形進行分析，建立一個新的鑒別勵磁涌流判據，該判據對硬體要求不高，可以在現有一般硬體平臺上實現；並編寫以b樣條函數為母小波的小波變換判據演算法程序。
  15. The software of the system have been compiled on the base of data sampling. the system used double - closed loop and pid method, one loop is speed control, the other is curret control

    系統軟體中，以中斷響應方式，實現電機轉速和電機電流實時採集、處理和控制；通過常數值切換法，實現電機的變結構控制。
  16. Motion control is a comprehensive subject. modern ac drive is a important embranchment in the field of motion control. however, it is difficult to rea1ize high - performance ac drive systems because induction motors are a kind of strongly - coupled nonlinear system with many variables and the torque is not easy to control. with vector control technology decoupling and torque control of ac motor are solved. the basic idea of vector control is that three - phase system is equiva1ent to two - phase system by coordinate transformation and it realizes the decoupling between field current and torque current of the stator in order to control the flux and current respectively, thus induction motor can be considered dc motor and high performance is achieved easily. with the progress of electric and electronic technology and the development of computer, high - integrated special modules and high - precision digital signal processor ( dsp ) are applied to ac drive so that vector control has been developed rapidly

    但是高性能的交流調速系統實現很困難，這是因為交流電機是多變量、強耦合的非線性系統，不易實現高性能轉矩控制。矢量控制技術則解決了交流電機解耦與轉矩控制問題，其基本思路? ?應用坐標變換將三相等效為二相，實現定子勵磁電流分量與轉矩電流分量之間的解耦，達到對交流電機磁鏈與電流分別控制的目的，交流電機等效為直流電機實現高性能調速。隨著電力電子技術的進步，計算機技術飛躍發展，高度集成的專用模塊和高精度的數字信號處理器應用於交流傳動系統中，促進矢量控制迅猛發展，日趨成熟。
  17. It also builds the mathematic model of all section of vscf ac exited wind power generation system on a - b - b and d - q coordinate system by the coordinate commutation technology. the thesis gives the characteristics of torque, active power, reactive power and the steady - state analysis of it. it proves that the capability of wind generator is determined to slip, the amplitude and phase of rotor voltage, the phase dispatch between stator voltage and rotor voltage

    並分析了交流勵磁風力發電機作變速恆頻運行時的工作原理，闡述了與同步發電機、異步發電機的不同之處，分析了其能量平衡關系，在坐標變換技術的幫助下，詳細推導了交流勵磁發電機在a - b - c坐標系和d - q坐標系下的數學模型，分析並模擬了其有功和無功特性、轉矩和功率調節特性、穩態運行和機械特性，證明了發電機的性能由轉差率、轉子電壓的相位和幅值、定轉子電壓相位差所決定的。
  18. And power loss analysis of srs and the layout design related to srs are very important to the proper design. with a small signal mathematic model of half - bridge converter, the relationship between performance of power supply and frequency domain characteristics of the system is analyzed. based on the above study and some simulation the system design is completed

    文中在給出了結合單繞組自驅動方案的對稱半橋變換器穩態原理分析、同步整流管損耗分析暨選擇原則、同步整流管相關電路的布局設計后，建立了對稱半橋變換器的小信號數學模型，分析了電源系統時域性能指標與頻域特性之間的聯系，在此基礎上完成了系統的設計。
  19. Combining with the practical project, the development of an instrument for multi - channel harmonic detection and analysis were described in the third chapter, including the system structure, hardware and software of the device. then the technology of multi - channel data gathering was discussed, and some key techniques have been presented including high precision 、 high speed sampling of the voltage and current, fast flourier transform ( fft ), data compression and storage techniques, planar graphic fitting, three dimensional graphic projection, multithreading and the computer graphics techniques

    第三章結合多通道諧波監測及故障錄波一體化裝置的研製這一課題，介紹了裝置的體系結構和硬體、軟體構成，詳細介紹了在裝置研究過程中所提出的關鍵技術，主要包括電流電壓信號高精度、高速采樣技術，快速傅立葉變換fft 、數據壓縮存儲技術，多線程技術，二維圖形擬合、三維圖形投影技術及海量存儲技術，計算機圖形技術等。
  20. Since that the choosing line hardware for the neutral ungrounded system has just passed part of the dynamic simulative test, matlab software was chosen to do a lot of simulative tests on single phase - to - grounding fault. and the simulative sampling ratio is almost the same as the hardware ' s. because there is a low wave filter in the hardware, i choose the db15 wave - let to carry out the multidimensional decomposition on the sample by the method of one dimension discrete wavelet in order to obtain low frequency signal including the high frequency transient information on single phase - to - grounding fault

    鑒于實驗室已有的小電流接地系統選線硬體的研製只通過了實驗室里的動模試驗，故選用matlab軟體對小電流接地系統進行大量的單相接地故障模擬試驗，模擬的采樣率和硬體基本一致，由於硬體中帶有低通濾波器，故在進行采樣數據的morlet小波分析時先採用db15小波對采樣進行一維離散小波的多尺度分解，使得分解得到的低頻信號剛好包括了小電流接地系統單相接地故障時的暫態高頻信息，然後對這一信息再繼續進行小波演算法分析，分析結論表明利用變換后的實部、虛部和模值能夠較準確的實現單相接地故障時的故障選線和暫態高頻分量的提取。
分享友人
分享到 Line

分享到臉書