無效電壓 的英文怎麼說
中文拼音 [wúxiàodiànyā]
無效電壓
英文
dead voltage- 無 : 無Ⅰ動詞(沒有) not have; there is not; be without Ⅱ名詞1 (沒有) nothing; nil 2 (姓氏) a surn...
- 效 : Ⅰ名詞(效果; 功用) effect; efficiency; result Ⅱ動詞1 (仿效) imitate; follow the example of 2 ...
- 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...
- 壓 : 壓構詞成分。
- 無效 : of no avail; to no avail; invalid; null and void; nullity (合同等的); in vain; unavailability; ...
- 電壓 : voltage; electric tension; electric voltage
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In the positioning servo - system, which generally is configured by the d. c. pulse width modulator ( pwm ) velocity governing system and position servo - loop, the parameter perturbance of pwm velocity loop really exist by reason of such as the load behavior ; power voltage supply ; operating setting value, etc. 1, 2 , and it cannot be ignored. by using the identification technique to form the mathematical model of the system, authors have confirmed the facts. therefore, to design the discrete sliding mode controller ( dsmc ) of the positioning servo - system, the perturbed parameters value bounds of the pwm velocity loop, which is as the controlled plant of position servo - loop, should be accounted. consequently, the design principle of dsmc for accounting system with parameter perturbance is proposed by the authors. the proposed method can ensure the stability of system with parameter perturbance and the behavior of non - overshoot, fast precise positioning. in order to reveal the effects of the design method, the comparative research work is done by the authors. also, it has been tested in an industrial experiment, the results proved it is satisfactory
由直流脈寬調速系統( pwm )和位置環構成的定位系統中,速度環的參數隨負載特性;電網電壓;給定工況而攝動是不容忽視的.作者通過系統辨識建模也證實了這一事實1 , 2 .因此在設計位置環的離散滑模控制時,必須針對速度環(即位置環的控制對象)的參數攝動范圍採用「對象參數攝動離散滑模控制器的設計方法」 ,以確保系統在參數攝動時的穩定性和快速、無超調、準確定位的優良動態品質.為剖析該設計方法的控制效果,本文作了對比性研究,並將該設計方法用於工業試驗中,取得了滿意的結果The operation principleresult of saving power , mate rial and reliability of ac and dc usual auto - converting saving power instrument are expounded, which the operation - coil of ac contactor given ac and dc voltage is usual, output is even dc, on and off and keeping voltage non - contactor auto - convert
論述了與交流接觸器操作線圈適配的交直流輸入(操作)電壓通用、恆直流輸出、吸合與保持電壓無觸點自動轉換節電器的工作原理;接觸器配用節電器后的節能節材效果及節電器的可靠性。Because of its good electrical conductivity, cfrc specimens will engender joule effect when a relatively low voltage was added to them. if there are flaws inside, the surface temperature distribution of the specimens should be uneven. therefore, infrared thermograph ndt can be conducted
利用碳纖維混凝土良好的導電性,通過對碳纖維混凝土試件施加較低的電壓,使其產生焦耳效應,如果試件內部存在缺陷,將在表面產生溫度差,從而可以利用紅外熱像技術進行無損檢測。In the paper, the four methods based on the evaluation of source ’ s reactive power are analyzed. those are voltage sensitivity ( vs ), pv curves, back - up generation and equivalent reactive compensation ( erc ) methods
由此文章分析了四種評估無功容量價值的方法:電壓靈敏度法、 pv曲線法、備用發電量法和等效無功補償法。First from system aspect, this paper uses voltage sensitivity, pv curves method, equivalent reactive compensation method, back - up generation method to evaluate the reactive value of the generators in seven buses system and ieee 14 buses system. the vs and pv methods can evaluate the source ' s ability of tracking the load ' s variation. the erc and back - up methods can evaluate the availability of replacing other generators. the value determines the cost
從對系統貢獻角度,採用電壓靈敏度方法( vs法) 、 pv曲線法、等效無功補償法( erc ) 、無功備用方法來確定一個七節點系統中的發電機的無功價值和ieee14節點系統的發電機的無功價值,電壓靈敏度法和pv曲線法可比較出不同電源跟蹤負荷變化的靈敏度大小,而等效無功補償法和無功備用方法可比較出不同電源替換其它發電機是否是最有效率的。Influence of dc - rail zero - voltage notch on the output of the inverter is investigated, and an important conclusion is obtained that the direction of output current of the inverter is not effected by the voltage deviation produced by dc - rail zero - voltage notch, on the basis of which, a new simple correction approach is put forward. experiment results show that the proposed correction method is effective
探索了直流母線零電壓凹槽對逆變器輸出特性的影響,得出了母線零電壓凹槽形成的輸出電壓偏差與逆變器輸出電流方向無關這一重要結論,在此基礎上,提出了一種簡便的校正新方法,通過試驗驗證了該校正方法的有效性。Our object is an intermediate frequency modem of a software defined radio transmitter - receiver of multi - service, multi - modulationmode and multi - processdatarate. first, related software defined radio theory is introduced ; later, channels of transmitter - receiver are designed with consideration of data format, modulation, fec, interwaving. and scrambling ; emphasis is placed on theory and implementation of an audio compression algorithm cvsd ( continuous variable slope delta modulation ) and a fec technique convolutional coding - decoding
本文首先介紹了相關的軟體無線電理論;然後完成了包括數據格式,調制方式,糾錯碼方式,交織器和擾碼器等部分的中頻數據機通道設計;接著著重介紹了系統中使用的音頻壓縮演算法cvsd (連續可變斜率增量調制)的原理和實現,以及作為前向糾錯碼的卷積碼編碼理論和編解碼的高效實現。The main work and conclusion for this paper is as following : according to the flashover test results of several kinds of iced insulators under positive voltage and negative voltage, this paper obtained : for the single porcelain insulator, the single glass insulator and the composite insulator bridged completely by icicle, the metal cathode ' s strong ability of emission electron is the primary reason that results in the lower negative flashover voltage ; the position difference of the high resistance district in method anode side results in that porcelain insulator cluster and glass insulator cluster have an evident effect of polarity ; when less ice and no icicle at the brim of the sheds, due to numerous non - polar arcs on the composite surface, the effects of polarity of composite insulator was lost using the test method of the average flashover voltage in the freezing period, dc flashover performances were investigated of several insulators with some typical structures and different material
本文的主要工作和結論如下:在人工氣候室內,根據不同覆冰絕緣子正、負極性下的閃絡試驗結果,得出負極性電弧金屬陰極的強電子發射能力造成了單片瓷、玻璃絕緣子及被冰凌橋接的合成絕緣子有較低負極性冰閃電壓;正極性電弧金屬陽極側產生高電阻區所處位置的差異使得瓷和玻璃絕緣子串具有明顯的極性效應;覆冰較少時,合成絕緣子表面出現數量較多的非極性電弧使合成絕緣子無極性效應。利用覆冰期內平均閃絡電壓的試驗方法,對不同材質和結構的絕緣子在覆冰、低氣壓和污穢共存環境中的直流閃絡特性進行了研究。試驗結果表明,直流平均閃絡電壓隨著海拔的升高、覆冰量的增加以及污穢度的增加而降低,且其特徵指數與絕緣子結構、覆冰量、覆冰狀態、污穢度等有關。In this paper, a new control strategy based on the adaptive deadbeat voltage space vector is presented. this control scheme has a lower sample frequency and a smaller difference between switch frequency and sample frequency. it has many advantages, such as producing zero vectors organically, tracing exactly, non - shaking, etc. and its dynamic response is better
對于電能質量調節器來講, pwm跟隨指令參考信號的控制性能在很大程度上影響著裝置的補償效果,本文選擇無差拍電壓空間矢量控制為系統控制策略,這種控制方法具有采樣頻率低,開關頻率與采樣頻率的差距小,能有機地產主零矢量、跟蹤精確以及無抖振等優點,動態響應快。Placing facilities for reactive power compensation can reduce network loss effectively as well as improve transmission capacity and regulate voltage profile
在配電系統中加裝無功補償設備,可達到降低網損的效果,此外還可以提高電網輸送能力和改善電壓質量。The reactive power optimization of a radial distribution system can efficiently minimize the real power losses and improve voltage level of it, so that the yearly running charge will be reduced and the quality of power energy can be increased
配電網無功優化可以有效地降低網路有功損耗,提高系統的電壓合格率,從而降低網路運行費用,提高供電質量。Capacitors dispatch of distribution system is an efficient method to network loss reduction and voltage improvement in the distribution system operation. it is an important component of distribution automation system ( das ). the thesis mainly discusses reactive optimal control of distribution system
首先,研究了配電網無功優化控制的基本理論,討論了配電網無功優化控制對電壓和有功損耗的影響,提出配電饋線電容器優化控制對進一步降低配電網的有功損耗效果顯著。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Through theoretic reckoning and simulating analyzing, several control strategies for shunt apf were compared and chose ip - iq arithmetic of the instantaneous reactive power theory control strategy as the right scheme to produce the instructing current. based on it, some new control arithmetic was subjoined to suppress the resonance in system and balance the dc side capacitor voltage. two topologies of main circuit were compared and chose the three - phase voltage - source converter with a split - capacitor as its main circuit structure
通過理論計算和模擬分析,比較了並聯型apf的幾種控制策略的優點和缺點,從中選擇瞬時無功理論控制策略i _ p - i _ q計算方式為指令電流產生的演算法,並在此基礎上增加了抑制系統諧振和平衡直流側電容電壓的控制;比較了並聯型apf主電路的兩種常見形式,從中選擇了三相電壓型變流器的主電路形式;算出適合該apf的直流側電容和出線電感的參數;設計出能有效消除apf產生的高次諧波的高通濾波器。( 3 ) reactive power optimal of radial network is a very complex nonlinear discrete optimal problem. to ensure the speediness, feasibility and optimality, evolution algorithm is improved by combination with interior point sequence linear optimal algorithm and principle of var balance. the improved algorithm is applied to the reactive power optimization and achieves distinct effect
( 3 )配網網路無功優化是一個非常復雜的非線性離散優化問題,為了保證計算結果的快速性、可行性和最優性,本文結合內點法的逐次線性優化方法,以及配網電壓調節的特點,對模擬進化優化方法進行了改進,並將該演算法應用於配網無功優化問題的求解,取得了顯著的效果。( 2 ) reactive power optimal of hv network is a very complex nonlinear discrete optimal problem. to ensure the speediness, feasibility and optimality, evolution algorithm is improved by combination with interior point sequence linear optimal algorithm and expert knowledge of voltage / var adjustment. the improved algorithm is applied to the reactive power optimization and achieves distinct effect
( 2 )高壓網路無功優化是一個非常復雜的非線性離散優化問題,為了保證計算結果的快速性、可行性和最優性,本文結合內點法的逐次線性優化方法,以及電壓無功調節的專家經驗,對模擬進化優化方法進行了改進,並將該演算法應用於無功優化問題的求解,取得了顯著的效果。Reactive power and voltage control in the distribution systems is very important. it makes the running of the systems more safe and stable and economical. it can also decrease the real power loss and improve the voltage
在配電系統中進行無功電壓控制能夠有效地降低有功功率損耗、改善電壓水平,對系統的安全穩定經濟運行具有重要意義。This paper explicitly describes the optical measurement of the electric parameters in the high - voltage electric power system, and an optic fiber large current sensor based on farady magnetooptic effect and an optic fiber high voltage sensor based on the linear transformation characteristic of led are developed from research on both theory and experiments. by combining the two sensors to form a synchronous system, the task of harmonic analysis, phase demodulation, power and wattless power computation is accomplished, which helps to monitor and control the electric power system
本文詳細論述了電力系統高壓電網電參量的光學測量的一種實現方法,從理論和實驗兩方面研究了基於farady磁光效應的光纖電流傳感器及基於led線性電光轉換特性的光纖電壓傳感器,並聯合兩種傳感器形成了電壓、電流的同步測量系統,實現了諧波分析、鑒相及有功、無功功率的計算,可對電能質量進行監控。It is both a theoretic and a practical project. after analyzing several identification methods, the writer put forward a method based on t - model equivalent circuit. to consider the skin effect, the writer modified the t - model equivalent circuit, adding the skin effect coefficients
經過分析幾種常用的電機參數辨識方法,如頻響法,最小二乘法和卡爾曼濾波法等之後發現在本課題的前提條件? ?空載全電壓起動下無法進行辨識,因此藉助于電機的t型等效電路模型。Compared with the traditional ballast, it has the advantage of less power dissipation, less weight, no flicker, no noise and capability of ignition on the low supply voltage
與長期使用的電感式(也叫電磁式)鎮流器比較,電子鎮流器具有節電效果顯著、體積小、重量輕、無閃爍、無噪聲以及在較低的電源電壓下仍然可以啟動熒光燈的優點。分享友人