線對地電壓 的英文怎麼說
中文拼音 [xiànduìdediànyā]
線對地電壓
英文
line-to-earth voltage-
According to the quickly adjustable characteristic of the peterson coil grounding system, this dissertation proposes a new control strategy. when the system is in operation, the strategy can limit the series resonance over - voltage by using the off - resonance method. when fault occurs, the strategy can conveniently suppressing arc by rapidly adjusting the inductance value of the peterson coil to the point, which the resonance with grounding capacitance of the power network is occurred
依據可控硅控制消弧線圈接地系統的快速可控性,一改傳統的電網正常運行時調節消弧線圈接近於全補償的預調諧方法,提出正常運行時採用脫諧方法抑制串聯諧振過電壓;故障時立即調節消弧線圈電感量達到與對地電容諧振,以利熄弧的新型調節原理和方法。A model of the interface state density distribution near by valence band is presented, and the dependence of the threshold voltage on temperature, the c - v characteristics and the subthreshold characteristics are predicted exactly with this model ; the effects of s / d series resistance on the output characteristics, transfer characteristics and effective mobility of sic pmosfets are analyzed. thirdly, the output characteristics and the drain breakdown characteristics are modeled with the procedure medici. the output characteristics in the room temperature and 300 ? are simulated, and the effects of gate voltage. contact resistance, interface state and other factors on sic pmos drain breakdown characteristics are analyzed
提出了一個價帶附近的界面態分佈模型,用該模型較好地描述了sicpmos器件閾值電壓隨溫度的變化關系、 c - v特性曲線以及亞閾特性曲線;分析了源漏寄生電阻對sicpmos器件輸出特性、轉移特性以及有效遷移率的影響;論文中用模擬軟體medici模擬了sicpmos器件的輸出特性和漏擊穿特性,分別模擬了室溫下和300時sicpmos器件的輸出特性,分析了柵電壓、接觸電阻、界面態以及其他因素對sicpmos擊穿特性的影響。The problem about neutral - point - grounding mode is an all - around technical problem which associated with not only power system reliability , insulation coordination , electromagnetic interference , but assault safety 。 in china , the neutral grounding modes of the 10kv net involved of none grounding, grounding by arc suppressing coils, resistance grounding or reactance grounding in the past 。 with the development of civic power network , low resistance grounding mode was used to restrain the over voltage, particularly in guangzhou, shanghai , beijing , and zhuhai etc. it was reported that the over - voltage level of low resistance grounding mode is lower than that of arc suppressing coil mode, but the operation carried out the other way 。 at substations in guangzhou and shanghai it was found that the low resistance grounding mode is successful 。 but in some areas , such as zhuhai , substations grounding with low resistance revealed some problems , including power supply reliability rapidly dropping , transmitting line often tripping ; and person safety being threatened 。 so interiorly the grounding mode selection of the 10kv network was disputed, which mainly focused on the fault form of 10kv net grounding, the apply area of suppressing arcing coil grounding mode, power supply reliability level of the two modes, person safety, communication interfere and the workload of maintenance
爭議點主要是在10kv電網接地故障的形式、消弧線圈接地的應用范圍、兩種運行方式供電可靠性的高低、人身安全、通訊干擾和運行維護工作量等諸多方面。 11 17本論文就是針對以電纜為主的城區10kv電網中性點接地方式的選擇問題進行研究。論文首先對10kv電網的中性點運行各種方式進行分析,比較各方式的特點,然後以重慶儲奇門變電站10kv電網的實際參數來建立數值計算模型,在考慮了電網接地電容電流變化、中性點電阻取值大小、接地點接地電阻值變化等多種影響因素的情況下,對中性點經消弧線圈接地和經小電阻接地方式下電網的過電壓水平和接地點短路電流大小進行了數值計算,其計算結果與電科院所作現場試驗進行了比較。An automatic fault location method is proposed based on ftu after the circuit analysis of single line - to - ground fault in distribution networks
通過對配電網發生單相接地故障后饋線的電壓、電流變化規律的分析,論文提出了基於饋線現場監控終端ftu的故障點智能定位方法。The stability of electric power system has been being focused for a long time toprevent a power system from losing synchronism after sudden fault , researchers have done much work and got many accomplishments this paper applied the direct feedback linearization ( dfl ) technique on the power system , a strong nonlinear system simulation results by matlab proved this method efficiency main works and results are as follows : this paper compared some existing methods in excitation control , fast valve control and coordinated control respectively, analyzed the developments and actuality of nonlinear control research in brief, illustrated why ransient stability could be greatly improved by using the fast valve control in chapter 3 , indicated the importance of coordinated control farther this paper introduced the inverse system theory, based on which , discussed the dfl theory, pointed out which had consistency with the inverse theory, expanded the dfl theory combined the idiographic model equations , made which adapt to the model of a single machine - infinite bus power system this paper referenced abundance articles and educed a set of equations , which could describe the dynamical process of excitation and fast valve control for synchronous generators in the equations , there were several very important parameters of power system - - rotor angle ( ) , rotor speed ( ) , generator q axis voltage ( eq ) , transient voltage ( e ' q ) , active power ( pe ) , mechanical input power ( pm ) , valve opening ( ) , generator terminal voltage ( vt ) , based on the model , nonlinear coordinated controller and terminal voltage optimal controller have been designed by using the expanded dfl theory and lq optimal control theory the simulation results showed that the controller could keep power system transiently stable under the effects of a symmetrical 3 - phase short circuit fault , which achieved better postfault regulation compared with another two routine methods , one is the proportion excitation controller and proportion fast valve controller, the other is the proportion excitation controller and the optimal fast valve controller, which could exert good performance when met 1ittle disturbance either
在介紹逆系統理論的基礎上,詳細介紹了dfl理論,通過比較闡明了dfl理論其本質是逆系統方法的一類,並結合具體課題推導出的模型方程將dfl理論進行了擴展,使之適應于電力系統這個強非線性對象。通過參考大量的書籍文獻推導出一套實用的可將大型汽輪發電機勵磁與汽門綜合起來進行控制的模型方程,此模型方程涵蓋了電力系統中特別引人注目的幾個量- -轉子角、轉子轉速、發電機q軸電勢eq 、暫態電勢e ' q 、有功功率pe 、機械功率pm 、汽門開度、機端電壓vt ,在此基礎上建立了實用的電力系統簡化的數學模型,並將擴展的dfl理論應用於此模型系統,結合線性二次型最優控制理論設計出大型汽輪發電機的非線性綜合控制器及機端電壓最優控制器,通過模擬實驗與採用常規的按電壓偏差進行調節的比例式勵磁控制器+汽門比例控制及採用常規的按電壓偏差進行調節的比例式勵磁調節器和基於二次型性能指標設計的最優快控汽門(考慮發電機的飽和因素)進行了對比,證實了採用此種控制器可以有效地提高電力系統的暫態穩定性,並且在電力系統遭受小干擾時同樣具有良好的調節性能。All the transmission lines of west - east electricity transmitting project are inevitable to crossing the high altitude and icing areas. for the reducing of the air pressure and the absolute humidity, the electricity strength of insulators will drop obviously. therefore, it must be considered the effect on the insulators " flashover voltage caused by the change of altitude and ice when the insulation cooperation of transmission lines are being designed
「西電東送」工程的所有輸電線路都不可避免的要經過高海拔和覆冰地區,由於大氣壓力和絕對濕度的降低會使絕緣子的電氣強度顯著下降,因此在進行輸電線路的絕緣配合設計時必須考慮到海拔高度和覆冰的變化對絕緣子的閃絡電壓影響。Applying relative arithmetic to all kinds of faults and calculating off - line, we can master time - distance relation chart for all kinds of faults. computation indicates : when transmission lines occur faults, the data window of protection algorithm consisting of prefault and postfault data at the same time has important significance. the following methods are useful to achieve the inverse time characteristic : calculating impedance by using flourier in a full cycle, calculating work voltage by using fault component, calculating the torque created by a phase comparator or a magnitude comparator
實際的計算表明:輸電線路發生故障后,用故障前後的數據同時充滿保護演算法的數據窗,對于快速切除近區故障具有很重要的意義;同時利用故障前後的數據,下述方法可以比較好地實現距離保護的反時限特性:直接用全周傅里葉演算法進行阻抗計算;採用工頻變化量阻抗繼電器進行工作電壓的計算;採用轉矩的思想進行轉矩的計算。This thesis not only analysed the serious results of deviation of electricd pressure, which was harm for equipments and personal safety, caused by disconnection of null line, but also proposed effective protecting measure for mulfunction, such as repetition earth protecting measures and so on
摘要分析了零線斷線造成電壓偏移而對設備和人身安全帶來的嚴重後果,提出了重復接地等有效的故障保護措施。Arc - grounding fault line selection is the paper ' s key point and innovative point about small current grounding power systems. a lot of simulations are made based on the change rule and the character of fault voltage, fault current. the simulation study declare that the use of the method of wavelet analysis can select the fault line when the arc - grounding fault take place, it will play a important directive role in the research of the protection equipment
對小電流接地系統電弧故障的選線模擬是本文的重點,也是一個創新點,本文從研究的角度,在深入分析電弧接地時故障電壓、電流的特點和變化情況的基礎上,進行了大量的選線模擬,模擬表明電弧故障時,小波分析方法也能準確地選出故障線路,這對研製高性能的接地保護裝置將起到重要的指導作用。The fluid properties and strata pressure have obviousely changed during the high water cut stage, which exert unfavorable influence on determining formation water resistivity based on spontaneous potential curves. from the analysis of the mechanism for forming
針對油田高含水期地層流體性質和地層壓力的變化給應用自然電位曲線求取地層水電阻率產生不利影響的實際問題,從自然電位產生的機理出發,研究了應用自然電位曲線求取地層水電阻率的方法。However, some unique geographical characters, such as fire grounding, bamboo grounding and treetop grounding, can cause single phase high - impedance grounding fault frequently. since the voltage drops down very little and the voltage among three phases keeps symmetric, this fault increases the difficulty of the check on this fault
然而,由火焰接地、毛竹接地或樹梢接地等原因引起的單相高阻接地故障,由於電壓降小、三相線間電壓依然幾乎對稱,從而增加了高阻接地檢測的難度。Microprocessor distance protection set is one of the most important protections for high - pressure transmission lines. when high pressure transmission line occurs fault, due to it ' s high voltage level, faults brings big impact to power system and users. the closer the faults occur, the bigger impact it brings
高壓線路發生故障時,由於電壓等級高,涉及面大,對于電力系統以及電力用戶沖擊很大;高壓線路故障地點距離保護安裝處越近,對于電力系統以及電力用戶的沖擊越大;距離保護的近區故障快速動作具有很重要的意義,本文基於上述目的研究微機距離保護的反時限。Though standard cast resin dry - type transformers can meet the demands of most consumers. we still have to proceed special designing of transformers for special application field and operating conditions, such as single phase transformers, regulating transformers with onload tap changer, double voltage transformers, isolating transformers, rectifying transformers, earthing transformers and transformers with special tapping arrangement, which we are supplying to consumers all over the country
雖然標準的樹脂絕緣乾式變壓器已能滿足大多數用戶的要求,但是對于某些特殊的應用領域與使用條件仍需我們進行特殊設計。諸如單相有載調壓雙電壓變換隔離整流接地以及有特殊出線排列的變壓器,我公司在不斷地提供給各地的用戶。Obtained by emtp program and the egm, this paper studies on lightning protection performance on 500kv double circuit transmission line the distributed parameter model of tower is built when analyzing the back stroking lightning protection performance for double circuit line, it can truly reflect the spreading course of lightning current on the tower, furthermore, considering the randomness of working voltage ' s phase when lightning strokes the top tower and supposing the probability of lightning appearing arbitrary phase in a cycle of ac is equal, this paper brings forward the statistical method to calculate the rate of back stroking on double circuit line
本文利用emtp程序、擊距法對500kv同桿雙回線路的耐雷性能進行了研究。在分析同桿雙回線路的反擊耐雷性能時,建立了桿塔的分佈參數計算模型,此模型可以真實地反映雷電流在桿塔上的傳播過程。並針對雷擊塔頂時,導線運行電壓相位角的隨機性,本文假定雷擊出現于交流一周期的任一角度區間內的概率相等,提出了利用統計法計算同桿雙回線路的反擊跳閘率。To put into operation a large amount of non - linear load, make in harmony wave of rural power grids serious becoming in pollution, pass to rural local electric wire netting main in harmony analysis of wave source, put forward in order to restrain from insert rural power grids in harmony wave source voltage total in harmony wave distortion rate and the containing rate change last device number pulsating for increase of goal, increase the pulse of the current change device and install light specified value electricity active wave filter mix with passive wave filter near the harmonics source to control the wave in harmony
摘要大量非線性負荷的投運,使農村電網的諧波污染日趨嚴重,通過對農村地方電網主要諧波源的分析,最終提出了以限制接入農村電網的諧波源的電壓總諧波畸變率和各次諧波電壓含有率為目標的增加換流裝置脈動數,以及在諧波源附近裝設小額定值的電力有源濾波器配以無源濾波器的混合型電力濾波方式,以進行諧波治理。It can be predicated that the study results are useful to the design of overvoltage protective device in electric power system and the development of canceling arc light earthed overvoltage device and small electric current chosen equipment
本文的研究結果對電力系統過電壓保護裝置的設計及消除弧光接地過電壓和小電流選線裝置的開發具有實際指導意義。Through the monitoring on the frequency performance and square - wave response performance of manganese - zinc ferrite coil with different sizes., different ratios of winding and different matching impedances, the result shows that manganese - zinc ferrite coil with proper ratio of winding and matching impedance can effectively restrain the interference and damage which the over - voltage and large - current signals of the power system do to the on - line monitoring system
通過對不同尺寸、不同匝數比和不同匹配阻抗下的錳鋅鐵氧體線圈的頻帶性能、方波響應性能測試實驗,結果表明:適當匝數比和匹配阻抗的錳鋅鐵氧體線圈可以有效地抑制系統過電壓和大電流信號對在線監測系統干擾和破壞。By analyzing the refraction 、 reflection process of fault transient current traveling wave of high voltage and characteristics of refraction 、 reflection coefficient systematically, a new fault location method of single ended traveling wave is presented. it can not only identify the reflection wave for fault location efficiently, but also not be affected by the structure and length of line. fault earthed resistance 、 fault type 、 system impedance and can locate fault in adjacent areas accurately
論文深入地分析了高壓線路故障暫態電流行波的波折、反射過程以及折、反射系數的特點,提出了新的單端行波故障測距方法,它不僅能夠有效地識別出測距所用的反射波,而且幾乎不受線路結構、長短、故障接地電阻、故障類型、系統阻抗的影響,在近區仍可以準確地進行測距;同時模擬阻波器的特徵,設計了低通數字濾波器,對通過了低通數字濾波器的暫態故障電流行波再次進行小波分析,並利用本文提出的單端行波故障測距方法進行故障定位,結論是所提出的測距方法在實際應用中仍是有效的。Based on the results, the article analysis the main factors : the voltage level and the current of the line, the height of the line, the distance between two phases, the structure and the location of the lines, that affect the distribution in human body, and gets some basic principles
根據計算結果,分析了超高壓輸電線的電壓等級、電流、離地高度、導線的相對位置結構和距離等影響人體內電磁場分佈的主要因素,得出一些基本規律。Line to earth voltage
線路對地電壓分享友人