零相變換 的英文怎麼說
中文拼音 [língxiāngbiànhuàn]
零相變換
英文
zero phase shift-
In the system, the collimation semiconductor laser - scanned beam scanning two perpendiculars direct of one plane of the measured workpiece at the same time is made. the beams with the dimension information of two perpendiculars direct are processed by the scanning receive system, the high - speed photoelectric transition and electronic data process. two measured results of the diametric directs and ellipse tolerance, etc, parameter, of the turning workpiece on the same plane are obtained by non - contact automatic measurement
在單向激光掃描檢測技術的基礎之上,提出了一種雙向激光掃描檢測系統,其採用激光掃描檢測技術與特殊光學系統相結合,用準直半導體激光掃描光束對被測工件徑向某一截面的兩個相互垂直方向同時掃描,經掃描接收光學系統、高速光電變換、電子學系統和微機數據處理系統,對將攜帶有垂直方向被測量信息的光束進行處理,實現了回轉體工件同一截面兩個垂直方向的徑向尺寸和橢圓度等參數的非接觸自動測量,解決了同時非接觸測量回轉體零件同一截面兩個徑向尺寸的難題,它具有高速,高精度和非接觸自動測量等特點。Phase - shifted zero - voltage - switching pwm full bridge converter can realize zvs for the power switches with the use of the leakage inductance of the transformer and the intrinsic capacitors of the power switches, so it is used widely for medium and high power applications
移相控制零電壓開關pwm全橋變換器利用變壓器的漏感和開關管的結電容可以實現開關管的零電壓開關,在中大功率的場合應用廣泛。2 rayleigy and weibull distribution ground clutter for airborne phased array radar ( apar ) general pulse signal was simulate with method of zero memory nonlinear transform
二、利用零記憶非線性變換法實現機載相控陣雷達常規脈沖情況下的瑞利分佈、韋伯爾分佈的地面雜波模擬。In the second method, wavelet transform is combined with modal transform, and transient travelling - wave signal is used. after three phase signals are decomposed into their modal components, the wavelet transform coefficient of ground mode can be used to identify approximate position of fault, and the wavelet transform coefficient of aerial mode is used for identifying arrival time of traveling - wave
第二種方法將小波變換與模式變換理論結合起來,採用的是暫態行波信號,首先將三相信號轉換成模式分量,零模分量的小波變換系數用於判別故障的大致位置,然後利用線模分量的小波變換系數來確定行波到達時間。Conventional hard switching technology has several flaws below : on and off loss, inductive off, capacitive on and diode recover problems. comparing with it, the loss of on and off decreases markedly, as the switches are on and off in zero voltage or zero current cases. and also the size of converter becomes smaller because of the higher of switching frequency
傳統硬開關技術由於存在開通關斷損耗大、感性關斷、容性開通、二極體反向恢復等問題,與之相比,軟開關技術在零電壓或零電流條件下導通,開關損耗明顯降低,加上開關頻率的提高使得變換器的體積得以減小,這也是軟開關技術受到青睞的原因。The soft switching, phase - shifted pwm and bi - directional dc - dc converter hang together, depress circuit switching loss and noise effectively, which provide condition to increase switch frequency, efficiency and reduce size and weight for the converter ; at the same time, it is proved the converter can achieve zvs in larger load variation, and the converter has the virtue of structure compact, voltage and current stress small such as ordinary hard switch converter
該變換器把軟開關技術和相移控制pwm技術以及雙向dc - dc變換器技術有機結合在一起,有效地降低了電路的開關損耗和開關噪聲,為變換器裝置提高開關頻率、效率以及降低尺寸及重量提供了良好的條件;同時,能拓寬零電壓開關的范圍,使變換器在較寬的負載變化范圍內都能實現軟開關。Research on modulation strategy of matrix converter to reduce common - mode voltage
用於抑制矩陣變換器共模電壓的零輸出換相策略Two kinds of method to divide the photo into blocks are presented in the dissertation, then the techniques of appending zero, dct transform and changing low frequency coefficents are utilized to hide information ( in fact, information is masked in dc components ). so information is hided in the low frequency domain of a photo. furthermore, good quantity evaluation is got after compared with original photos
本文通過對原圖像分別使用兩種分塊方法進行分塊,然後通過補零, dct變換,改變低頻系數來進行信息隱藏(實際上是在直流分量上隱藏信息) ,實現了在低頻域進行信息隱藏的目的,且使得隱藏后的圖像與原圖像相比具有較好的質量評價。The proposed jtc greatly reduces the intensity and width of the strong dc component, sharpens the correlation peak, eliminates cross - correlations among each input target, and the conjugate cross - correlation between the reference and input targets at the same time. in order to calculate the discriminant probability of the objects, a simple but self - explainable statistic function was presented to show where the true object and false object occurred in the unknown input image sequence
在此基礎上,論文提出了基於位相編碼振幅調制的畸變不變多目標識別聯合變換相關技術,即通過改變隨機位相模板的調制因子的大小來改善相關輸出的性能,一步消除了共軛相關項、輸入待識別圖像之間的互相關項,並大大降低了零級相關峰的能量和寬度。A novel high - power pollution - free smps is presented in this paper, which accomplishes simultaneously the goal of soft - switching pwm, the input / output isolation, the output voltage regulation and three - phase pfc with a single - stage power processor and simple pseudo - phase - shift control circuit. therefore, compared with the normal two - stage system, the single - stage power supply has simpler structure, lower cost, higher efficiency and easier to control. the proposed smps can be used in the three - phase power system, and can output high power over kw - order and input / output ( i / o ) isolation dc power supply
本文提出的新型無污染大功率開關電源正是採用三相三線制輸入電源,利用單級偽相移零電壓零電流開關脈寬調制( pps - zvzcs - pwm )全橋變換器完,成功率因數校正( pfc )和輸出電壓快速調節、隔離的雙重功能,並且該變換器開關管在零電壓或零電流下通斷,顯著的減小了emi 。The following is the main works and conclusions of this thesis. the novel upfc needs high power rate because it is generally used in high voltage transmission lines. after studied high - power converters and the literatures of upfc, the main circuit topology of novel upfc base on diode - clamping multilevel inverter is presented and the principle of using novel upfc to eliminate zero sequence and negative sequence currents is analyzed
本文所做的主要工作及得出的主要結論如下:由於upfc一般用於高壓輸電線,其功率等級要求很高,在綜合研究大功率變換器和upfc現有文獻的基礎上,提出了基於二極體箝位多電平變換器的新型upfc的主電路拓撲,分析了用其來濾出高壓輸電線非全相運行時所產生的零序和負序電流的原理。The clamping diodes conduct only once in a switching period, and the resonant inductance current is smaller in zero state, leading to a higher efficiency and reduced duty cycle loss. the operation principle of the improved converter and the comparison with the original converter are analyzed in this paper. the effect of the blocking capacitor in series with the transformer or resonant inductance is discussed, and a best scheme is determined
本文將諧振電感和變壓器交換位置,使變壓器與滯后橋臂相連,這樣箝位二極體在一個開關周期中只導通一次,同時零狀態時諧振電感電流較小,有利於提高變換效率和減小占空比丟失,本文分析改進后變換器的工作原理,並與改進前的變換器進行對比,討論隔直電容在不同位置對變換器工作的影響,確定一種最佳工程方案。Firstly, we analyze the transient and steady character of single phase high - impedance grounding fault. secondly, based on wavelet analysis on checking mutational signal and direction high frequency protection theory, utilizing zero sequence current and module current, this paper provides a new scheme including fault starting element, fault phase selection element, directional element and main criterion. this scheme can bear high impedance and is immune to system surge and frequency warp, which gets over the shortcoming of the lack of sensitivity
由於現有的保護方案無法快速有效地切除此類故障,本文在詳細分析了單相高阻接地故障的穩態和暫態特性的基礎上,從小波分析原理出發,利用小波變換檢測突變信號的原理,以零序電流、模電流等為研究對象,結合方向高頻保護的原理,設計了一套包含啟動元件、選相元件、方向元件、主保護的保護新方案。Design verifications shall be done for any new components or design by review of alternative calculations and relevant test operations such as hydrostatic and functional tests
任何新零件的設計確認都將進行變換方法計算和相關的測試操作,如液壓試驗和功能測試。4. problem of circular array ’ s high side - lobe ( relative to main - lobe ) and the lower depth of zeros is resolved using mode space transform, which changing uniform
4 .利用模式空間變換將均勻圓形陣列轉化成虛擬的均勻線陣,解決了圓形陣列副瓣電平較高(相對于主瓣) 、零點深度相對較淺的問題。The theory of phase - shifted full - bridge zvs pwm dc / dc converter circuit is studied and the phase - shifted controller uc3875 is used for phase - shifted control circuit
文中研究了移相全橋零電壓pwmdc dc變換器的工作原理,使用移相控制晶元uc3875設計了移相控制電路。In this thesis, the tradition phase - shift full - bridge zvs dc / dc converter are analyzed, and then a new dc / dc full - bridge converter employing switches clamping in secondary side of transformer is proposed, and the converter employing saturable inductor clamping are studied, and zvs ( zero - voltage - switching ) can be easily achieve by experiment validate
本文分析了一些傳統的移相全橋軟開關變換器,提出了開關管箝位dc dc全橋變換器拓撲方案,並對飽和電感器箝位dc dc全橋變換器進行了研究,並進行實驗驗證,從而解決了開關管的零電壓開關問題。By using phase shifting control between right bridge leg and left bridge leg, the output cy cloconverter commutating while the bi - polarity three - state high frequency ac volage from the input cycloconveter is zero, . and commutation overlap of the output cycloconverter and polarity selection of the input voltage, the leakage inductance energy and the output filtering inductance current are naturally commutated, and zvs switching of the output cycloconverter are realized, the surge voltage and surge current of the output cycloconverters are overcome
通過輸入周波變換器右橋臂相對左橋臂的移相,讓輸出周波變換器功率開關在輸入周波變換器輸出的高頻交流電壓為零期間進行換流,並藉助輸出周波變換器換流重疊和輸入電壓極性選擇,從而實現了變壓器漏感能量和輸出濾波電感電流的自然換流、輸出周波變換器的zvs開關,解決了輸出周波變換器固有的電壓過沖和環流問題。Compared with phase - shift control, pwm plus phase - shift control can reduce the current stresses and rms currents of the converter. the loss of the converter can also decrease. lt is proved the converter can achieve zvs in larger load variation
與常規相移控制方式相比, pwm加相移控制方式能減小變換器的電流應力,減小通態損耗,同時也能拓寬零電壓開關的范圍,使變換器在較寬的負載變化范圍內都能實現軟開關。Firstly, the basic theory of full - bridge phase - shift zvs pwm converters are expatiated and another three kinds of circuits of full - bridge phase - shift zvs pwm converters are discussed. there are four kinds of problems which are emphasized : how to expand the zvs range ; how to reduce the circulation in the primary side of the transformer in order to minimize the on state losses ; how to decrease the loss of effective duty circle and how to eliminate the parasitic oscillation of the output rectifiers
本文首先分析了基本的全橋移相zvsdc dc變換器的工作原理,為解決滯后橋臂不易實現零電壓開關( zvs )的情況,討論了另外三種全橋移相zvsdc dc變換器的電路拓撲,重點分析並解決了四個方面的問題:如何擴大zvs的負載范圍;減小變壓器原邊環流,降低變換器系統通態損耗;減少變壓器次邊有效占空比丟失;消除輸出整流二極體的寄生振蕩。分享友人