瞬時流率 的英文怎麼說
中文拼音 [shùnshíliúlǜ]
瞬時流率
英文
instantaneous flow rate-
The reactive power compensation is an important engineering in the power system. the active reactive power compensator designed in this text takes the instantaneous reactive power theory of three - phase as foundation, and is formed by the reactive current testing circuit, current tracking control circuit and the main circuit, and among them the current tracking control circuit is formed by instruction current arithmetic circuit, current polarity checkout circuit and current tracking control logic circuit three parts in the circuit form
無功功率補償是電力系統中的一項重要工程,本文所設計的有源無功功率補償器是以三相瞬時無功功率理論為基礎的,它由無功電流檢測電路、電流跟蹤控制電路和主電路三大部分組成,其中電流跟蹤控制電路由指令電流運算電路、電流極性檢測電路和電流跟蹤控制邏輯電路三部分構成。By studying traditional instantaneous power theory in single - phase circuit, we developed a real - time detecting method in this paper based on digital technology, which can detect harmonic current and fundamental reactive current in both single - phase and three - phase circuits
本文通過對于單相電路瞬時功率理論的分析研究,提出了一種基於數字技術的單相和三相電路諧波和無功電流的實時檢測方法。This paper focuses on the control strategies to improve the performance of the three - phase ac - dc pwm voltage - source - converters ( vsr ) under unbalanced power supply. the problems such as negative sequences current, voltage and current harmonics and un - constant ( un - smooth ) power flow from ac to dc side are discussed in this paper. the analytical solutions for negative sequence current and harmonic current elimination are obtained by fully feed - forward of negative sequence voltage and producing a non - harmonic current command of the inner - loop
電網不平衡時,基於電網平衡為約束條件設計的三相vsr將出現不正常運行狀態,比如三相vsr交流電流中出現負序分量,使交流電流嚴重不對稱;直流電壓和交流電流中出現非特徵諧波分量,使直流電壓和交流電流波形發生嚴重畸變;三相vsr從電網吸收不平衡的瞬時功率等一系列問題。The control tactics of space voltage vector are investigated, and the simplified algorithm which judges the sector location of reference vector and calculates switch operation time is put forward. by analyzing the current hysteresis control, the relation between switch frequency, and hysteresis bandwidth and input inductance of pwm rectifier is deduced. by applying instantaneous power theory, the principle of pwm rectifier power control is analyzed, and the direct power control by matlab toolbox through estimating active power and reactive power with virtual flux is realized, and the simulation results prove that it is correct
對常用空間電壓矢量控制策略進行分析,提出了給定參考矢量所在區間判斷的簡化方法,以及電壓矢量作用時間的求取方法;分析了電流滯環控制策略,推導出開關頻率與滯環帶寬以及整流器輸入電感之間的關系;應用瞬時功率理論分析pwm整流器功率控制原理,通過虛擬磁鏈估計有功功率和無功功率,用matlab實現了直接功率控制,並驗證了該控制方法的正確性。The emulational calculating theories of traction power supply system ' s operating charts combine with actual things of engineering design at present in chapter three, to set up traction web current distributing mathematical model, integral distributing mathematical model, locomotive distribution and obtaining current model at every moment, and on which making use of mathematical planning methods to set up mathematical models is based at every moment in every instance interval of the railroads. for instance, instantaneous current, instantaneous voltage descent and effective current, main changing capacity and so on, in addition, there are the minimum power shortage model, the optimal transformer substation location, the least engineering expenditure, the optimal mathematical model of traction power supply system. optimize design ' s algorithm of traction power supply system is introduced in detail in chapter four, where programming idea and realizing method of the computer software are given an explanation
本研究主要進行了以下工作:結合牽引供電系統運行圖的模擬原理和現行工程設計的實際情況,建立了牽引網電流分佈、積分分佈、任一時刻機車分佈和取流的數學模型;應用數學規劃方法建立了任一距離區間、任一時刻的瞬時電流、瞬時電壓降數學模型和有效電流、主變容量和主變壓降、最小功率損失、最佳變電所容量、最佳變電所位置、最少工程費用、最少運營維護費用和牽引供電系統方案最優等方面的數學模型;闡明了牽引供電系統優化設計的演算法和計算機軟體編程思想及實現方法;進行了工程實例計算;最後,對牽引供電系統優化設計技術應用進行了總結。This method can rapidly extract speed law from starting current of dc motor with fairly good precision, and thus the torque - speed characteristic can be acquired
並通過提取直流電機起動過程電流信號的瞬時頻率有效地研製了一套無轉矩轉速傳感器直流電機的快速測試系統。The main circuit is consisted of 18 thyristors circuit and protection circuit. with the help of control subsystem, it can get the output of low frequency voltage ( current ) with the shape of sine wave ; the core of the control subsystem is the cpu of 87c196kc, and the synchronization circuit, the pulse - widen circuit, and the power - enlarged circuit form the accessorial subsystem of the control system. it possesses all the functions of digital triggering, digital tuning, analog / digital conversion ; the input transfer can isolate the input and output ; and the circumfluence reactor can reduce the circumfluence
主迴路採用由18個晶閘管組成的三相零式電路,並輔以晶閘管的保護電路,通過控制可以得到低頻正弦波的電壓(電流)輸出;控制迴路主要以87c196kccpu為核心,其外圍電路包括同步電路,脈沖拓寬電路,功率放大驅動電路等,完成了數字觸發、數字調節、模數轉換等功能;進線電源變壓器具有變壓和隔離作用;環流電抗器則實現了有效抑制主迴路瞬時脈動環流的功能。From the perspective of minimum transmission losses, an instantaneous reactive power theory for systems with any number of phases and with or without neutral line is developed. under the new definition, each quantity has its own physical meaning, and the zero sequence current can be decomposed into active and reactive components. furthermore, a generalized compensation method for zero sequence current is developed
從輸電損耗最小的角度出發,提出了任意相無中性線或有中性線系統的瞬時無功功率理論,在新的理論下,每個量都有清晰的物理意義,且能分解出零序電流的有功分量和無功分量,並給出了通用的零序電流補償方法,揭示了瞬時無功功率理論與傳統平均意義下的無功功率理論的聯系及本質區別,從而為研究hvdc - vsc及各種facts裝置的無功功率控制奠定了理論基礎。Taking dc motor test as an example, a creative idea of applications of some advanced signal processing tools, such as time - frequency analysis, wavelet, and instantaneous frequency ( if ) evaluation, in motor testing field is presented. the paper systematically summarizes basic theories of time - frequency analysis and wavelet transform based on which an in - depth research of effective if evaluation based on wavelet ridge and wavelet curve is carried out. in the end a fast t - n characteristic testing system with neither torque nor speed sensor is successfully developed
本論文主要關注小波分析在電機性能自動測試系統中的應用,針對傳統電機測試系統以及信號處理技術在電機測試領域中應用的不足,以直流電機為例,提出了將時頻分析、小波包變換以及基於小波脊的瞬時頻率提取方法應用到電機測試領域的新思路;較系統地總結了時頻分析和小波變換的基本理論,深入探討了基於小波脊線和小波曲線的瞬時頻率提取,並成功開發了基於正交小波包分析和基於小波脊線的瞬時頻率提取的無轉矩轉速傳感器的直流電機快速測試系統。The algorithm is also applied in the broken rotor bars detection in squirrel cage induction machines, which is dependent on detecting the twice slip frequency modulation due to the speed or torque in the stator current, and the rotor bar faults can be detected effectively without some preprocessing
指出可以利用信號的小波脊線來提取頻率隨時間連續變換的信號的瞬時頻率,並將該瞬時頻率提取演算法成功地應用到異步電動機定子起動電流信號的分析中,有效地提取出了轉子斷條故障特徵。Effects of fluctuating temperature of gas flow on the instantaneous devolatilization rate of pulverized coal particle
氣流溫度脈動對煤粉顆粒瞬時熱解揮發速率的影響Japanese scholar akagi h. put forward instantaneous reactive power theory in 1980s, 20 century, meeting the demand for real time and instantaneousness
20世紀80年代由日本學者赤木泰文提出的瞬時無功功率理論滿足了對電流諧波和基波無功電流快速檢測的要求。Based on the combustion model, the intermediate combustion products, the rate of the heat release in the swirl chamber, the engine ' s transient pressure and temperature are traced in details during the calculation
在此模型基礎上,對發動機缸內燃燒的中間產物、渦流室的放熱率、缸內瞬時壓力和溫度進行了分析。Using numerical simulation method, detailed dynamic pressure variations, transient gas temperature and mass flow rate in the ptr, and the coefficient of performance of ptr and the exergy losses of all parts of ptr were obtained
用數值模擬方法得到了製冷機內部各點的壓力、溫度、質量流率等參數的瞬時變化情況及整機的製冷系數,並得到了製冷機各部件的(火用)損失及整機的(火用)效率。Firstly, wall ’ s transfer matrix is deduced by laplace transformation based on 3r2c thermal network model. secondly, frequency response of transfer matrix is calculated. thirdly, we make the frequency response of transfer matrix of stimulation model equate the theoretical frequency response of wall transient heat conduction by applying appropriate identification algorithm, from which we can obtain every polynomial ’ s coefficient of model transfer function, then each parameter of resistance and capacitance is calculated by appropriate optimization algorithm
首先,根據模擬熱流網路模型用拉普拉斯變換推出墻體的傳遞矩陣;然後,計算傳遞矩陣的頻率響應;最後,採用頻域回歸方法求出模型傳遞函數各次項的系數,進而通過一定的優化演算法確定模型的各個熱阻、熱容參數,使通過模型建立的多項式s -傳遞函數與墻體瞬時傳熱的理論超越s -傳遞函數完全等價。For this reason, we redefined the instantaneous reactive power so as to make it easier for detecting harmonic current and fundamental reactive current
為此,重新定義了系統瞬時無功功率,使其更易於諧波和無功電流的實時檢測。A closed - loop detecting approach of harmonic and reactive current based on instantaneous reactive power theory is proposed, its base design rules are given
摘要分析了基於瞬時無功功率理論的諧波及無功電流檢測原理,在此基礎上提出一種自適應閉環控制的檢測系統,給出優化設計的基本原則。( 5 ) basing on the exploring of the functions of cohesion force and friction force during rheology course and the assumptin that viscosity lost according viscosic strain, a constitutive model for viscous, elastic and plastic rock is set up, which can simulate the third course of creep. then the impact of transcient damage to rheology is discussed and corresponding creep model for rock is proposed
( 5 )在探導巖石顆粒間粘聚力和顆粒間摩擦力在巖石發生流變過程中的作用基礎上假設粘性失效按流變應變統計概率分佈,建立了巖石粘彈塑性本構關系,能夠描述巖石蠕變加速階段特徵;討論了瞬時損傷對巖石流變的影響和相應的損傷蠕變模型建模問題。Taking single four - quadrant power switch mode circuit as an example, the operational mode, steady principles, transient voltage feedback control strategy, the auxiliary switching power supply and parallel technology of this kind of converters are investigated. the output characteristic curve and the design for the key circuit parameters are given
以單四象限功率開關式電路拓撲為例,分析研究了這類變換器工作模式、穩態原理與電壓瞬時值反饋控制策略,給出了變換器的外特性曲線、關鍵電路參數、機內輔助開關電源的設計,對電流源高頻交流環節ac ac變換器並聯擴容技術進行了研究。Taking single four - quadrant power switch mode circuit as an example, the operational mode, steady principles, transient voltage feedback control strategy of current mode ac - ac mode ac / ac converters with high frequency link are investigated. the output characteristic curve and the design for the key circuit parameters are given
以單四象限功率開關式拓撲為例,分析研究了電流源交?交型高頻環節ac ac變換器的工作模式、穩態原理與電壓瞬時值反饋控制策略,給出了變換器的關鍵電路參數的設計準則和變換器的外特性曲線。分享友人