電換算因數 的英文怎麼說
中文拼音 [diànhuànsuànyīnshǔ]
電換算因數
英文
electrical conversion factor- 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...
- 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
- 算 : Ⅰ動詞1 (計算數目) calculate; reckon; compute; figure 2 (計算進去) include; count 3 (謀劃;計...
- 因 : Ⅰ動詞[書面語] (沿襲) follow; carry on Ⅱ介詞1 [書面語] (憑借; 根據) on the basis of; in accord...
- 數 : 數副詞(屢次) frequently; repeatedly
- 換算 : [數學] matrixing; scaler; conversion; convert; translation換算表 conversion table; equivalent tab...
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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。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。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。In addition, the author puts forward that the eggs could be recognized based on the difference in the frequencies of their prompted sounds. because the eggs " prompted sounds are lied on low frequency bands, the microphone and sound amplifier that have excellent duration response should be used. the output signal from the sound amplifier is transferred to data signal by a / d card before it is put into computer
蛋品激勵出的聲音主要集中在低頻段,因此選擇在低頻段有好的頻率響應特性的麥克風和放大電路;放大輸出信號通過a / d採集板變換成相應的電壓數值信號送入計算機,對離散的信號數據進行傅立葉變換得到它的頻譜圖和各頻段能量分布圖;而後將能量分佈特徵數據作為神經網路的輸入值,這樣,好蛋和破損蛋的模型就建立起來。The theoretical calculation has a good agreement with the test result in a 400mw hydro - generator. many factors that effect coolant flow and heat exchange was analyzed
通過400mw水輪發電機空心導線的實驗數據,驗證了計算程序的正確性,分析了各因素對介質流動和換熱的影響。To accept the current signal from high negative voltage circuit, the analog ground is raised to a certain positive voltage, which makes it possible for the signal amplitude to be compressed at the same time of its polarity reversion. a pi control program special for laser gyro current control is brought forward according to the conventional pid control method, in which the control signal is figured out corresponding to the difference between the sample and the reference value by turn of proportion - short step integral - long step integral. and at the end of this paper, a comparison of system performance on different conditions is made and the key elements influencing system performance are educed
利用集成a / d 、 d / a轉換器的新型晶元aduc824 ,實現了電流(電壓)采樣?數據處理?電流控制的閉環控制結構;地電位的抬升解決了a / d轉換器對負高壓迴路電流采樣時的輸入范圍匹配問題;控制信號反相的同時進行幅度壓縮,使得輸出調整電壓的解析度提高;根據常規的比例?積分?微分( pid )調節模型,針對陀螺系統的特性,給出了一種可以滿足系統要求、據采樣值偏差大小進行的比例?大步長積分?小步長積分、分層次比例?積分演算法;不同條件下系統穩流性能的對比、分析在論文最後給出,並據此找出了決定該系統穩流精度的關鍵因素,提出了系統的改進意見。The electrical damping within the whole subsynchronous frequency range is calculated. the impacts of the unit interaction factor between hvdc and turbine generator, the dc power level, the firing delay angle and the parameter settings of hvdc controller on the have the potential danger of subsynchronous oscillation
在整個次同步頻率范圍內,計算得到了系統電氣阻尼,並詳盡地分析了同步發電機與hvdc的耦合程度、直流輸送功率水平,換流閥觸發角大小以及控制器參數等因素對系統電氣阻尼的影響。The current in the dac ’ s output can drive the load, and the structure can save a buffer consisted of operational amplifier, so the structure can achieve high speed with no close - loop and feedback in this circuit
該10位分段式電流舵型數模轉換器的輸出端可直接用電流輸出來驅動負載阻抗,省去運算放大器構成的輸出緩沖,整個電路中沒有形成閉環和反饋,因此這種電路結構可以達到很高的速度。Abstract : we conduct a theoretical study on the properties of a bound polaron in a quantum well under an electric field using linear combination operator and unitary transformation methods, which are valid in the whole range of electron - lo phonon coupling. the changing relations between the ground - state energy of the bound polaron in the quantum well and the coulomb bound potential, the electric field strength, and the well width are derived. the numerical results show that the ground - state energy increases with the increase of the electric field strength and the coulomb bound potential and decreases as the well width increases
文摘:採用線性組合算符及幺正變換方法研究了電場對量子阱弱耦合束縛極化子的性質的影響.推導出量子阱中束縛極化子的基態能量和庫侖束縛勢、電場和阱寬的變化關系.數值計算結果表明,基態能量因電場和庫侖束縛勢的不同而不同,隨電場和庫侖束縛勢的增大而增大,隨阱寬的增大而迅速減小First, variable speed constant frequency wind energy convertion theory is described in this paper, then presents a review on the development of wind turbines control and the main types of generator and static converters used to interface variable speed wind turbines to the electric grid. then discuss main circuit constructure and advantage of direct drive wind energy conversion system and introduce pitch - control method for wind power traction and electric power stability. simply aerodynamic characteristic of the turbine is analysised and permanent magnet synchnonous generator math model is established. to convert the variable frequency electricity into utility grid, back to back four - quadrant pwm - vsi is used and three typies of control strategy is presented to capture the maximum wind energy and transmit energy. then simulation is implemented to test the control strategy. in the following chapter a simple ac - dc - ac converter with a dc - dc boosting chopper is proposed to transmit the wind energy into electricity energy and two control strategy is presented
建立了永磁電機和變流器的數學模型,針對雙pwm變頻器的特點提出了三種控制策略對變流器進行控制,通過變流器交-直-交的變換,將發電機發出的變頻變幅值交流電轉化為可用的恆定頻率的交流電,通過pwm調治能使其輸出功率因數為一,並且該控制系統功率因數為可調,能在特殊情況下同電網交換一定的無功功率,並通過對變流器的控制實現了最大風能俘獲的功能。最後採用matlab / simulink進行了模擬,取得了良好的模擬效果。在風力發電系統中,採用先進的最大功率俘獲演算法,能有效的從風中獲得最大的能量。The general transfer functions of pwm converter are developed and the small - signal transfer functions controlled by the duty cycle are given using matlab. the voltage adjuster and the current regulator of the control circuit are designed. the isolated cuk converter is analyzed and the features and the description of the uc3854 are presented in detail
論文分析了帶隔離變壓器的cuk變換電路,介紹了平均電流型功率因數校正晶元uc3854的結構、功能;根據uc3854的具體特點與要求,以設計一個具體、實用的帶pfc功能的開關電源為例,設計、計算了主電路電感l1 、 l2 、 c1 、 c2 、隔離變壓器以及電壓、電流調節器電路的參數及要求。It involves not only the detection of signal frequency, signal phase and power factor but also calculation and control of phase. the method of calculating phase is based on fast fourier transform algorithm ( fft ). it is used to calculate signal frequency, signal phase, power factor and the phase on / off time according to sampling instantaneous value of voltage and current
本文主要提出了採用信號處理技術(快速傅里葉變換fft ) ,根據電壓、電流采樣的瞬時值,計算信號頻率、信號相位、功率因數、分合閘相角的選相控制方法,並介紹了最終控制分合閘的原理與實現方法On one hand, the problem of " big horse pulls little wagon " is resolved and the working efficiency of motor is improved by optimizing way to control the stator ' s voltage ; on the other hand, an energy automatic processing system of " electric motor generates electricity " is developed, in which, the energy of the feedback of motor generating electricity is processed duly and correctly through real - time switch control of the generating electricity absorbing energy cell and is used at wellhead instead of returning power net
本課題運用新型電力電子技術和計算機控制技術研究開發了一種電機功率因數自調整及節能控制系統,一方面通過對定子電壓的尋優控制,解決了「大馬拉小車」問題,改善了電機的工作效率;另一方面開發了一種電機「倒發電」能量自動處理系統,通過倒發電吸收單元的實時切換控制,將倒發電反饋的能量及時準確地進行處理,使其在井口利用不返回電網。First, because pipelines are so complex that controlled object is high order, delay, coupling, nolinear and time - varing, it is difficult to realize closed loop control for it using valid mathematic model. to resolve this problem, the paper presents a fuzzy - pid control algorithm with self - adjusting regulation factor. second, if a moving motor supplied by inverter power is switched to be supplied by power supply, the impact of overload - voltage and overload - current appears
主要針對中、大容量供水系統中,由於供水管網鋪設復雜、彎管多、控制對象具有高階、滯后、耦合、非線性及參數時變的特點,難以利用有效的解析式數學模型進行閉環控制,以及多臺水泵並聯運行時,水泵電機由變頻電源供電向工頻電源供電切換過程中產生的過電壓過電流沖擊這兩個難題,提出了可調整因子fuzzy - pid控制演算法及利用鎖相環控制實現水泵電機由變頻電源向工頻電源的同頻同相平滑切換。Besides, digital signal processing technology in ac contactors electric life test is studied in this paper. under the principles of digital signal processing, using fft, the calculate process of power supply frequency and power factor is discussed
此外,本文研究了交流接觸器電壽命試驗中數據處理技術,應用數字信號處理理論,利用傅利葉變換,分析了電源頻率、功率因數的計算過程。The effect of each referred factor on the commutation torque ripple is calculated by the numerical computation so that the foundation is theoretically established for further research for reduction of commutation torque ripple, the design and control of the brushless dc motors
通過數值計算結果說明?各因素對換相轉矩波動的影響程度,為研究換相轉矩波動的減小措施和永磁無別電機的設計及控制提供了理論依據。分享友人