按比例擴大 的英文怎麼說
中文拼音 [ànbǐlìkuòdà]
按比例擴大
英文
scale up-
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。The reasoning of structured model : how to transfer structured model into mathematical model that can be solved by an arithmetic system ; the determination of the most appropriate target case includes two steps : the first is wide retrieval, and the second is extract retrieval that is a method driven by adaptation rules. the case base maintenance : case storage and case knowledge maintenance. the last part of this paper is about the real information system, which introduces the analysis and design of the information system and uses a real case to describe how the system operates
這些研究工作包括：事例和問題的知識表示：給出屬性集、結構集和目標集的事例表示方法；知識化模型的推理：結構化的模型如何轉化為求解系統可識別的屬性模型的過程；最相似事例的確定：兩步選擇過程，粗選過程按屬性相交度，精選按類比轉換的規則驅動的確定最相似事例的原則和方法；類比轉換的方法：確定在一定條件下的轉換方法；事例庫的維護：事例庫是可維護的，一方面隨著系統解決問題的增多，事例庫也會不斷擴大知識領域；另一方面，通過事例庫維護模塊，可以從用戶那裡得到新的建模知識。First, to ensure the children from rural then " access to higher education on an equal footing, compulsory education with no fees must be brought about with the more government ' s funding flowing to the schools in rural. second, we can increase appropriately the number of senior middle school students in rural
作者認為可以從三個方面著手：首先政府必須加大對農村義務教育的投入，優先在農村地區實行完全免費的義務教育；第二，適度擴大農村高中教育招生規模；第三，高考錄取名額依考生人數按比例分配。
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