轉發電流 的英文怎麼說
中文拼音 [zhuǎnfādiànliú]
轉發電流
英文
repeat current- 轉 : 轉構詞成分。
- 發 : 名詞(頭發) hair
- 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...
- 轉發 : retransmission; transmit; repeat; relay
- 電流 : current; galvanic current; electric current; electricity; current flow電流保護裝置 current protec...
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Repair of the slip ring on the alternator rotor
交流發電機轉子滑環的修復The test shall demonstrate to the satisfaction of the owner that the equipment meets all specified performance criteria, is properly installed and anchored, and operates smoothly throughout the specified speed range without exceeding the full load amperage rating of the motor or excessive motor heating
測試應該讓用戶滿意,證明這些設備符合所有規定的性能標準,經過正確的安裝和錨固,在額定轉速范圍內運行平穩,沒有超過電機的額定滿負荷運轉電流安培數,或發生電機過熱。Mems ( micro electromechanical system ) has become one of the most rapidly development technologies. along with the rapid development of mems techniques, capacitive sensor is used widely whose capacitance changes small, which has put forward the new request to the measurement technique. the common measure for capacitance measurement is that convert capacitance to voltage, electric current or frequency. the area of polar plate of the capacitor becomes smaller and smaller, and the total capacitance of micro capacitive sensor is usually several pico farad only. as a result, its change amount is smaller
Mems ( microelectromechanicalsystem )近年來發展最快的技術之一,隨著mems技術的快速發展,電容式加速度計的電容變化變化量越來越小,對檢測技術提出了新的要求。在電容式傳感器中,常用電容檢測電路是將其轉換為電壓、電流或者頻率信號。目前的微型電容傳感器的極板面積變得越來越小,電容總量只有幾個pf ,變化量就更小。That the earth has an iron - rich liquid core, sufficient energy to drive convection and a coriolis force to twist the convecting fluid are primary reasons why the geodynamo has sustained itself for billions of years
地球擁有富含鐵的液態核心、有足夠的能量驅動對流,並具有科氏力可使對流的流體扭轉,這些是地球發電機之所以能自我維持數十億年的主要原因。As a result, the electromagnetic field intensity is changed accordingly and fluctuating current in the damper coil is created. damping force is mostly produced because of the phase difference between fluctuating current and displacement of rotor. the formulas of fluctuating current and damping coefficient are deduced theoretically, and the calculated results are consistent with the experimental results
通過分析發現電磁阻尼器線圈內由於轉子渦動時變化的磁場而產生的波動電流與轉子位移間的相位差是產生阻尼的主要原因,推導了波動電流、阻尼系數的計算公式,並通過實驗展示了被動式電磁阻尼器的阻尼效應。It looks upon water resistant as load, simulate every instance of locomotive running and check its every parameter automatically, then collect and dispose these data of parameters, calculate the power of simulating running of locomotive, which is based on the current, and voltage of host dynamotor. afterward, it can be judged from the working state of locomotive. through experiment and adjust each parameter, it can provide important warrant to the components of locomotive whether they can work normally and credibly
即以水阻作為負載,模擬機車運行,對機車的主發電動機的電流、電壓和柴油機的轉速等參數進行檢測,並對檢測結果進行處理,計算出模擬機車運行時的功率,並以此為依據,對機車的工作狀念進行判斷,通過水阻試驗,調整有關參數,使機車運行時能發揮所要求的功率和滿足規定的工作特性。The two - point to earth short fault may cause short currents whic h can lead to serious accident. so it is necessary to monitor the state of field windings of turbo - generator and detect the kind of fault and predict its inclination. thus the security level of power system will be improved
由於發電機轉子兩點接地故障時會產生較大的短路電流,導致惡性事故的發生,因此對發電機轉子繞組進行狀態監測,判斷短路故障的形式和趨勢是十分必要,有助於提高系統安全運行水平。Many planets ( for example, ganymede, mercury, the earth, jupiter and saturn ) and stars ( for example, the sun ) possess intrinsic magnetic fields. the explanation for their existence and variation remains a great challenge to planetary scientists and astrophysicists. this article attempts to review some recent developments and difficulties in the study of magnetohydrodynamics for the electrically conducting fluid interiors of planets and stars. it is the fluid motions, usually driven by thermal convection, that generate and sustain magnetic fields through magnetohydrodynamic processes in planets and stars. in planets, the magnetohydrodynamic processes are strongly affected by the combined and inseparable effects of rotation, magnetic fields and spherical geometry. the key dynamics involves the interaction between the coriolis and lorentz forces. in the sun, it is the solar tachocline, a thin shear flow layer located at the base of the convection envelope, that plays an essential role in the solar magnetohydrodynamic processes which produce the 11 - year sunspot cycle. some results of a new nonlinear three - dimensional solar dynamo model are also presented
許多行星(如木衛三,水星,地球,木星和土星)和恆星(如太陽)具有內部磁場.對這些磁場的存在和變化的解釋對行星科學家和天體物理學家是一個巨大的挑戰.本文試圖總結行星和恆星的導電流體內部磁流體力學研究的新近發展和困難.一般由熱對流驅動的流動通過磁流體力學過程產生並維持在行星和恆星中的磁場.在行星中磁流體力學過程強烈地受到轉動,磁場和球幾何位型的綜合影響.其動力學的關鍵方面涉及科里奧利力和洛倫茲力間的相互作用.在太陽中其流線,即處于對流層的薄的剪切流層在太陽的磁流體力學過程中扮演了一個基本的角色,並由之產生了11年的太陽黑子周期.本文也給出了一個新的非線性三維太陽發電機模型From the last century ninetieth, microprocessor relay protection technology has been rapidly developed and widely used in our country. it has become an inevitably flow and trend in the development of relay protection technology. but there are scarce experimental devices of microprocessor relay protection at present in our country and the devices which are being used have the defect of function single, inconvenient, and high cost etc. based on this condition, an experimental and training system for the multifunctional microprocessor relay protection and substation integrated automation is explored and developed in this paper
從上個世紀九十年代起微機繼電保護技術在我國得到了快速的發展和廣泛的應用並已成為繼電保護技術發展不可逆轉的潮流和趨勢,但是微機保護實驗設備的開發在我國幾乎是一片空白,僅有的微機保護實驗設備也存在著功能單一、體積大、成本高等諸多缺點,基於這一現狀,本文著力研究和開發一種多功能微機保護與變電站綜合自動化實驗培訓系統。Value, and the current density and intensity versus the substorm phases. moreover, the characteristics of substorm current wedge are given special attention. it is found that the density and intensity of facs reach their peak during the expansion phase, the onset of the expansion phase is triggered when imf is changed to southward from northward or the southward imf decreases, and the positions of onset are most likely to be at the edge of plasma sheet near the earth
值分佈以及場向電流強度和密度隨亞暴位相的變化,並著重分析了亞暴電流楔的特徵。結果表明,亞暴膨脹相的場向電流強度和密度都達到極大值亞暴的膨脹相是由行星際磁場轉向或南向分量變小觸發的,其起始位置很可能位於近地等離子體片內邊緣。Torsional interaction exists between hvdc converters and turbine - generators, and negative electrical damping provided by hvdc may cause subsynchronous oscillation ( sso ) that can lead to turbine - generator shaft failure and electrical instability at oscillation frequencies lower than the fundamental system frequency
高壓直流輸電( high - voltage - direct - current - - - - hvdc )系統與臨近同步發電機組之間存在著扭振相互作用, hvdc的電氣負阻尼作用有可能引起機組在次同步頻率范圍的扭轉振蕩。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。In this paper, several scheme of vscf is compared firstly, of which gets doubly - fed generating mode. doubly - fed vscf wind power generating system uses a doubly - fed induction generator, which rotate speed can be able to change with wind turbine, and it ensures a constant - frequency output, by controlling the frequency of current input into rotor windings. in vector trans control system, the control of stator active power and the control of stator reactive power can be essentially decoupled, and the former is via torque component and the latter is via exciting component of stator current
本文首先比較了幾種變速恆頻方案,從中選擇了雙饋式變速恆頻方案;它運用雙饋電機的工作原理,允許發電機轉速變化,而在電機轉子側接入低頻勵磁電流,通過控制該電流的頻率,保證雙饋電機定子輸出的頻率恆定;再結合矢量控制技術,通過調節轉子電流來控制定子電流的轉矩分量和勵磁分量,相應獨立地控制發電機輸出的有功功率和無功功率。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。The contributions done are as follows : according to the mathematical model of doubly fed motor and the theory of vector control, a unit power factor of rotor control scheme is proposed. in the doubly fed adjustment system, in order to control magnetic torque of motor this scheme is designed by controlling the reverse direction between rotor voltage and current to keep the vertical direction between rotor current and flux. it is known from theoretical analysis that for partly decoupling this scheme is only effective under sub - synchronization speed, but not control the system and obtain steady state since speed adjustment system ca n ' t adjust the magnitude of rotor flux under sup - synchronization
而傳統的無速度傳感器雙饋調速矢量控制系統,由於採用磁鏈定向方法,在同步速附近存在較大的工作死區,針對上述問題,本文做了如下的研究工作:本文從雙饋電機的數學模型出發,根據矢量控制的基本原理,提出了一種轉子側功率因數為1的雙饋電機矢量控制方案的設想,即在雙饋調速時採用轉子電流定向的方法,並控制外加轉子電壓與轉子電流始終反相,以保持了轉子電流與轉子磁鏈矢量垂直,通過控制轉子電流的大小來達到控制電機電磁轉矩的要求。If balanced three - phase current flow through these three - phase distributed windings, a rotating magnetic field of constant amplitude and speed will be produced in the air gap and will induce current in the rotor circuit to produce torque
如果平衡型三相電流流經這三相分散式繞組,將在氣隙中產生振幅及速度穩定的旋轉磁場,並會誘發電流在轉子迴路產生轉矩。Llpa power push button switch is applicable to the motor of the voltage up to 500v and the capacity up to 3kw for directly starting run and breaking, also for infrequently turning on and off loaded current
Llpa系列控制按鈕開關是可適用於電壓500v和負載量為3kw的發動機直接運轉和阻斷,同時頻率運轉和電流負載。In this paper the predictive system of field current is studied using takagi - sugeno fuzzy system. the input parameters are drawn from the turbo - generator ' s stator
因此,本文利用基於神經網路集成的高木一關野模糊系統來建立發電機正常運行時轉子電流的預測模型。Abstract : through the analysis of the coordination characteristics between the switch and the fuses in combination, it is shown that the transfer current of combination can be decreased by reducing the prearcing time of fuses in the range of transfer current or by increasing the fuse - initiated opening time ( t0 ) of the switch. the ways to decrease the transfer current for present combinations are put forward
文摘:本文通過對組合電器中負荷開關與熔斷器之間的配合特性分析,認為減小熔斷器在轉移電流區域內的弧前時間或適當增加熔斷器觸發的負荷開關分閘時間t0 ,均可降低組合電器所需開斷的轉移電流值,並針對現有組合電器提出了減小轉移電流的具體方案。The steady state and transient characteristics of the aceg system are simulated, the harmonics of the emf and stator current and rotor current as well as mc ' s input current are researched. the operation characteristics of aceg with mc as an exciter are compared to those of aceg with ac - dc - ac converter and cycloconverter as an exciter. the results in this thesis will be helpful to the design of the aceg excitation control system
利用所建模型,對交流勵磁發電機系統的穩態調節特性、暫態特性進行了模擬研究;模擬研究了發電機定、轉子電流和感應電勢及變頻器輸入電流波形,並作了相應的諧波分析;與交-直-交變頻器和交-交變頻器作勵磁電源時發電機的運行特性進行了對比分析。分享友人