負阻振蕩 的英文怎麼說
中文拼音 [fùzǔzhèndàng]
負阻振蕩
英文
negative resistance oscillation-
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。The system parameters are developed at the same time, and some universal conclusions on the theoretical analysis of pll are reached. then, we have carried on analysis and research to the theory of differential delay ring voltage controlled oscillator ( vco ). on this basis, a improved differential delay ring vco with more efficient loads is described. this circuit has been designed and implemented in 0. 35 m cmos technology
本文還對差分延遲結構環形壓控振蕩器電路進行了深入的分析與研究，並提出了一種基於高質量電阻電路的主從差分延遲結構環形壓控振蕩器，其採用了一種新型的主從差分延遲結構，並用一個更有效、更穩定的負載電阻電路結構來替代vco設計常使用的單個mos管電阻結構，使其系統穩定性有了相應提高。Negative resistance oscillation
負阻振蕩According to these theories we know the reason of the emergence of low frequency oscillation is lacking positive damping even appearing negative damping. this problem can be classified as dynamic stability
從而得出，電力系統低頻振蕩是由於系統正阻尼不足甚至產生負阻尼而引起的，可以將其歸類為動態穩定問題。Through the deep study of f. d. demello dynamic model of electromechanical transition and synchronous generator theory, we proposed a new control strategy of excitation device that can eliminate the negative - damping phenomenon, which is directly against the cause of producing negative - damping represented as low frequency oscillation in the system
通過深入研究f . d . demello機電暫態的動力學模型以及同步發電機理論，針對系統產生負阻尼即低頻振蕩的原因，我們提出了一種新的可消除負阻尼現象的勵磁控制策略。On the contrary, because of the effect of positive damping provided by the inverter, the unit near a inveter will have no subsynchronous oscillation risk. based on the same method described above, a damping study is carried out for a hybrid ac / dc system, which include a hvdc link and an ac transmission line in parallel
研究表明，系統整流站附近的同步發電機組要承受電氣負阻尼作用，因此有可能引起機組低頻扭轉振蕩模式失穩；而hvdc的逆變站向其臨近同步發電機組提供正阻尼，因而機組不存在次同步振蕩危險。The characteristics of damping shows that the uncompensated parallel ac transmission line can release the coupling between the hvdc and generator and improve the damping of the system, hence the possibility of subsynchronous oscillation decrease. in such a system scheme, the hvdc system dominates the changes of damping due to the small magnitude of the damping provided by ac line. when the ac transmission line is compensated with a fixed series capacitor, the situation will be totally different
其中，並列運行的無串補交流輸電線路可以緩解hvdc與其臨近機組之間的機電耦合程度，改善hvdc的電氣負阻尼特性，從浙江大學博士學位論文摘要而減輕機組發生次同步振蕩的危險性，此時系統的整體電氣阻尼特性由hvdc的性質決定;但若交流線路中存在串聯補償電容，則系統幅值較大的電氣負阻尼不僅可能使整流站機組發生次同步振蕩，逆變站附近機組同樣存在發生次同步振蕩的可能性，此時系統的整體阻尼特性由串聯補償電容的性質決定。Unified power flow controller ( upfc ) is one of the most powerful and most promising controllers of facts. if we use upfc to control the transmission parameters, terminal voltage, line impedance and phase angle in normal situation and use it to compensate zero sequence and negative sequence currents when one of transmission lines is cut off, we can implement two phases operating in high voltage transmission lines, which can improve stability and reliability for the transmission system
統一潮流控制器（ upfc ）是功能最強、最具發展潛力的靈活交流輸電系統（ facts ）控制器之一，如果在常規條件下，用upfc實現輸電線路的電壓調節、移相、潮流控制、阻尼振蕩等功能，在發生單相永久性接地或單相斷路故障時，由傳統的三相跳閘改為單相跳閘，用upfc的並補來濾除兩端系統的零序和負序電流，用upfc的串補來提高輸電線的傳輸功率，以實現兩相長期運行，那麼輸電系統的穩定性、可靠性將大大提高。First of all, single port negative impedance oscillator is analyzed in the thesis. a design method of gunn diode vco is introduced and an vco chip using gunn diode is fabricated. the substrate of the vco chip is gaas with dimension of 4. 4mmx3. 9mm
本文首先對單埠負阻振蕩器進行了分析，給出了gunn二極體負阻振蕩器的設計方法，設計出了一個變容管調諧平面微帶gunn二極體vco晶元，該晶元以gaas為襯底，尺寸為4 . 4mm 3 . 9mm 。It also gives the motive of the ka - band vco and mixer, associated with the subject ' s requirement and the realistic conditions, according to which a proposal is confirmed that the gunn diode and the varactor are mounted in the same cavity to fulfill the vco and an antiparallel diode pair is used to fulfill the harmonic mixer. in chapter 2, based on the basic theory of negative resistance oscillating, we analyses the gunn oscillator and it ’ s tuning character. chapter 3 introduces the theory of millimeter - wave harmonic mixer
以此為根據結合課題需要和實驗室的實際條件，確定vco採用耿氏管腔體振蕩器形式，變容管與耿氏管安裝在同一個腔內以進一步減小體積，採用反向並聯二極體實現諧波混頻;第二章介紹負阻振蕩器理論及其調諧原理;第三章介紹毫米波諧波混頻器基本原理;第四章給出了振蕩器及諧波混頻器的設計過程，整個組件聯調的結果;最後是結束語，分析了電路中存在的問題，指出了改進方向。Some fundamentally influential factors such as systemic structure, the distribution of power flow, effects of excitation system and pss, as well as characteristics of load models, etc, are discussed in detail to study the systemic damping
隨后從系統結構、潮流分配方式、勵磁系統和電力系統穩定器的作用以及負荷特性等角度，詳細討論了影響互聯系統振蕩模式阻尼的因素，並研究了這些因素的相互作用。On the base of the fujian power system that has the special configuration of " large power generator with small power system " in 2000, constructs power system models of fujian and fujian interconnected with other parts, does a lot of calculation and analysis and simulation, researches the security mechanism and rule of the fujian special power system interconnected with large power system. the above connection can keep security and stability and can make obvious benefits, but when the transmission power reach to excessive quantity the main power grid will increases interconnected flow - in or flow - out exchange power load. the power operation state tended to instability ; the infirmable interconnection make s the damp infirmable
本文以2000年前後具有「大機組小電網」特殊結構的福建電力系統為背景，建立了福建電力系統及其與外部互聯的數學模型，開展大量的模擬計算分析，研究了「大帆組小電網」電力系統與大容量電力系統互聯偏弱的安全穩定性的機理和規律：前述互聯可以安全穩定運行，取得顯著效益，當傳輸功率達到一定量后，主網架增加了送出或吸收互聯交換功率的負載，系統運行狀態向穩定性水平有所下降的方向轉移；聯絡偏弱使阻尼偏弱，聯絡線小幅低頻振蕩和大幅低頻振蕩易被激發，聯絡線一旦重載斷開，系統高周或低調嚴重。分享友人