脈波調變 的英文怎麼說
中文拼音 [màibōdiàobiàn]
脈波調變
英文
pulse modulation; phase modulation （pm）-
The second, at the high frequency primary coil, when switch turn on with control signal ( the spwm pulse is modulated ), in the positive or negative semi - period of low frequency modulation signal, transformer coil with same direction voltage. the magnetic flux of transformer core will increase step by step. at the end, it leads to magnetic flux saturation
二、在高頻變壓器原邊，當開關管接收控制信號脈沖列（經調制的spwm波列）導通時，在低頻調制信號的正半周或負半周內，施加在變壓器繞組上的是同一方向的電壓，變壓器磁芯中的磁通可能將級進地逐漸增加，導致磁芯飽和，造成磁偏或單向磁化，導致低頻電信號放大失真或由於很大的磁化電流而無法正常工作。The algorithm of svpwm that is adopted by the system implements motor speed - regulation by control of magnitude and phase of motor flux. it can generate less harmonics in the output current of power inverter and less losses of ac motor, reduce pulsant component in output torque and raise availability of dc supply voltage
系統採用的svpwm演算法通過對空間磁鏈矢量幅值和相位的控制來調節電機轉速，減少了逆變器輸出電流的諧波，降低了脈動轉矩，提高了電壓的利用率。3. passive and active time - domain demodulation schemes were demonstrated based on a fiber bragg grating used as a tunable filter controlled by a piezoelectric stack, which was driven by an electrical sine wave signal. the measured strain applied on the sensor axially could be judged by observing the interval of the output between notches within a driving period in time - domain
利用匹配濾波技術，分別採用無源和有源方式，藉助受pzt驅動的解調光柵，將待測應變信息變為時序負脈沖間隔的變化，利用常規的示波器觀測同一掃描周期中兩負脈沖在時域中間隔的變化來確定待測應變的變化。1 m 0. 5, the phase - shifted angle 6 is controlled in term of sine law which makes the magnitude of resonant voltage track a reference sine voltage, and the resonant voltage is rectified, filtered, inverted and then the better sine - voltage output is obtained, theoretical analysis and experimental results show that for the resistive load and inductive load, the switches of leading leg of the phase - shift - controlled circuit are always turned on at zvs, and ones of lagging leg are turned on at zvs ( < 0 ) or turned off at zcs ( ( > 0 ), moreover, all switches in the low - frequency inverter are always turned on and off at zvs, the measured circuit efficiency for rated load reaches up to 88 %
從功率單向流動角度出發，提出了一種lcc諧振型恆頻移相單相高頻鏈逆變電路拓撲，在調制系數0 . 1 m 0 . 5情況下，控制移相角按正弦規律變化，使諧振電壓脈沖列的幅值追蹤參考正弦電壓信號，經過整流、濾波、低頻逆變，從而獲得正弦度較好的輸出電壓。理論分析和實驗結果證明對于阻性負載或阻感性負載，移相全橋具有超前橋臂零電壓開通，滯后橋臂或者零電壓開通（ _ 0 ）或者零電流關斷（ _ 0 ）的軟開關特性，而低頻逆變器的各個開關均實現零電壓條件下的開通與關斷。The study has completed the design of two - phase inverter and made up of the two - phase inverter - motor system for experimental use it is a variable frequency adjustable speed system with a open - loop control of rotational speed, which consists of voltage - controlled oscillator circulating assign device inverter circuit and two - phase induction motor a accurate mathematical model is set based on the whole system, and simulator program of dynamic and steady condition is established, which is used to calculate the dynamic and steady performance by kron and symmetrical coordinate converter by simulator calculation and experimental research with specific parameter of the system, a comparison is made between predicted and experimental characteristics, experimental measurements are shown to compare closely with corresponding theoretical result it is compared with some variable frequency adjus table speed system comprising inverter and single - phase induction motor from the system efficiency torque pulsation and the effect of two - phase inverter capacitance based on the conclusion, harmonic cancellation pulse width modulation control of a two - phase inverter - fed induction - motor drive system is researched, which cancelled the low harmonic and improve the system performance
通過對電機的kron變換和對稱分量變換，建立了系統較精確的數學模型，編制了系統動態及穩態運行的模擬計算程序分別計算系統的動態和穩態性能。通過對系統的具體參數進行了模擬運算和實驗研究，實驗和模擬結果進行比較，說明實驗和理論較為一致，並從系統效率、轉矩脈動及兩相逆變器電容的影響等方面與各種逆變器和單相異步電動機組成的變頻調速系統加以比較。在此基礎上，對兩相逆變器供電-異步電動機系統使用諧波抑制pwm控制進行了研究，由於減少了低次諧波，改善了系統性能。The detail study on the interaction between the electron beam and standing wave of complex cavity gyrotron with gradual transition and gyroklystron has been done in this dissertation, supported by the pre - study important items " the study on 8mm third harmonic gyrotron with a permanent magnet system " and " the study on 8mm high power gyroklystron ". the main works of this dissertation are listed as following : 1. the study on the rf distribution of the complex cavity with gradual transition is presented, in which the multi - modes coupling are taken into account
本論文就是結合該課題組的「九?五」重點項目「 8mm三次諧波永磁包裝迴旋管技術的研究」及「十?五」重點項目「 8mm高功率迴旋速調管技術的研究」 ，對以諧振腔為互作用高頻系統的迴旋脈塞器件中兩種典型的器件? ?迴旋振蕩管及迴旋速調管中電子注與駐波場的互作用進行了深入細致的探討和研究，其中迴旋振蕩管採用的是漸變復合腔。There are five parts are as follows : in part one, the concept of switching function is introduced first to establish the nonlinear mathematical model of the induction motor variable frequency speed adjustment system which is fed by a sine pulse width modulated ( spwm ) inverter and takes the effect of the main magnetic circuit saturation into consideration, then the low frequency oscillation of the system is simulated according to the model. next, from the view point of energy conversion of the inverter - induction system, a criterion for the low frequency oscillation is proposed to determine whether the system is in low frequency oscillation which is judged by whether the interval of the negative current component of the inverter input current is more than 1 / fc ( fc is the carrier wave frequency of the inverter ) or not
首先引入開關函數概念，建立了正弦脈寬調制（ spwm ）逆變器供電異步電動機，考慮主磁路飽和時的變頻調速系統整體數學模型，模擬系統的低頻振蕩；其次從逆變器-異步電動機系統能量轉換角度出發，提出通過檢測逆變器輸入電流中負電流的間隔時間是否大於1 / f _ c （ f _ c為逆變器載波頻率）來判定系統是否出現低頻振蕩；最後的實驗結果驗證了系統低頻振蕩建模和判據的實用性和正確性。The system can generate three - phase spwm pulses and has following characters : the range of modulation frequency is from 0 khz to 4 khz. and can be divided to 7 classes to control. the carrier frequency may be selected up to 24 khz, and can be divided to 8 classes to control ; rotational frequency is defined to 16 bits
該系統能產生三相六路正弦脈寬調制（ spwm ）波形;調制頻率范圍為0 4khz ，分7級控制; 16位的速度控制解析度;載波頻率分8級控制，最高可達24khz ;系統介面兼容intel系列和motorola系列單片機;該系統控制簡單、精確，易修改，可現場編程;同時具有脈沖延時小、最小脈沖刪除、過壓和過流保護功能等特點，可應用於pwm變頻調速系統的全數字化控制。According to the mechanism characteristics of the ac motor, with zero - voltage switching technology, the pdm converter mathematical models both the pwm and rectangular wave control mode are given in this paper. and the voltage and current harmonic analysis and the simulation waveforms of the output voltage, current and power are also described respectively
根據交流電機在恆轉矩區和恆功率區的特性，結合零電壓開關技術，分別給出相應的脈寬調制控制（ pwm ）方式和方波控制方式下的高頻交流脈沖密度調制變頻器的數學模型，電壓和電流的諧波分析以及輸出電壓、電流和功率的模擬波形。（ 2 ） the major circuit has been established, composed of rectifier 、 buck - chopper 、 push - pull inverter and matching network, which realizes high - power supersonic ac output. to achieve maximal output power, the pulse frequency modulation ( pfm ) has been applied to auto - adjustment of output frequency, which corresponds to the load ' s resonant frequency
（ 2 ）建立了超聲電源主電路，其中包括：整流、直流斬波、推挽逆變器和匹配網路等部分，實現了大功率超聲頻交流電的輸出，輸出頻率的脈頻調制（ pfm ）和輸出功率的脈寬調制（ pwm ） 。Unlike inverters for general purpose, auxiliary inverters of subway vehicle have the characters of high power, wide range of high dc input voltage, entirely sealed electronic units and natural cooling. single pulse width modulation ( pwm ) technology is found to be optimal by comparing several different high power inverter technologies and is utilized in the 2 - channel staircase inverter discussed in this thesis
針對地鐵車輛輔助逆變電源的大功率、直流側輸入電壓高且變化范圍寬、輸出電壓穩定且波形質量高，電子部件全密封且要求自然冷卻的特點，分析比較了幾種大功率逆變器技術方案，選擇單邊脈寬調制階梯波合成逆變器為研究對象。The author designed and developed a single phase mid - frequency inverter control unit, which is based on dual micro - processor system. the inverter is modulated by pre - set spwm pulse width wave
本文研製出一種基於雙微處理器（ mpu ）控制的單相中頻逆變電源控制裝置，逆變電路基於開關預置spwm波脈寬調制。According to the space vector modulation method of the equivalent structure of the ac - dc - ac transformation, the transformation relations of the matrix converter are deeply investigated. the ac - ac direct conversion control and the double - space - vector pwm scheme of the matrix converter are deduced, the four - step current commutation strategy of matrix converter is expatiated, the design method of input filter and over voltage protection circuit is analyzed, and the modeling and simulation of a three - phase matrix converter are implemented
從等效交-直-交變換的空間矢量調制方法出發，深入分析了矩陣式變頻器的變換關系，導出了交-交直接變換控制規律和雙空間矢量脈寬調制技術，闡述了矩陣式變頻器的換流控制策略，分析了輸入濾波器和過電壓保護電路的設計方法，實現了矩陣式變頻器的建模和運行分析。Firstly, the basic theory of switch reluctance generator ( srg ) is discussed in detailed, based on the mechanism electric energy converting analysis, non - linear analysis and non - linear simulation. three control methods of srg ( angle position control method, current chopping control method, pulse width modulation control method ) are deeply studied and analyzed. the electronic controller, which controlled by dsp or by hardware circuit are developed for low - power switched reluctance generation system
首先系統地研究了開關磁阻電機發電運行的基本理論，從機電能量變換的角度分析開關磁阻發電機的機電能量變化規律；通過非線性分析和非線性模擬方法，明晰開關磁阻電機發電本質，概括出開關磁阻電機發電運行的特點；系統、深入地研究了開關磁阻電機發電運行的控制方案（角度位置控制、電流斬波控制、脈寬調制控制） 。Pulse width modulation pwm
脈波寬度調變The performance of the electric vehicle is improved greatly in which the harmonic wave of output voltage, power loss and torque pulsation of the system are decreased by controlling the switch angles
它運用規則采樣法產生正弦脈寬調制波，通過開關角的控制抑制逆變器輸出電壓中的諧波分量，降低了電動機的損耗和轉矩脈動，使電動車的運行性能得到了較大改善。This paper studies on used the ac servo system based on ti dsp ( lf2407a ) and the foc and digital signal processing thorem, achieves following results : algorithm. we employ svpwm ( space voltage pwm ) algorithm, improve the efficiency of the electric source, and decrease the harmonious elements. we build the mathematic model of the system and simulate it on matlab platform, dsigne segmented pid regulator to adapt variable speed and widen the speed range. measurement. the velocity and electric current measuring, we adopt multi - sampling - rate and digital filter principles. as more improvements we make, the whole system gets a good results. pc control. the complete controlling system can be controlled remotely. so we develop the pc controlling program.
採用磁場定向脈寬調制演算法，提高了電源利用率，降低了逆變電壓的諧波，改善了電機的運行特性，降低了對電網的污染；在matlab平臺上建立了交流永磁同步伺服電機和電壓空間矢量脈寬調制控制系統的數學模型，在模擬的基礎上，對傳統pid調節器進行了改進，提出轉速調節器和電流調節器採用分段pid結構，根據給定轉速所處的區間，自動選擇相應pid調節器的參數，拓寬了調速范圍，提高了控制精度。Digital receiver and its forepart operational principle are discussed, then methods of instantaneous autorelation, short - time fourier transform, wigner distribution and wavelet analysis are introduced in detail. the advantages and disadvantages and the application range of these algorithms are given. based on the merits of these algorithms, a new method for signal modulation type analysis is presented
本文討論了數字接收機以及前端的工作過程，然後詳細闡述了瞬時自相關、短時傅立葉變換、 wd演算法、過零檢測和小波分析等各種演算法在脈內調制分析上的應用，分析了各演算法的優缺點，提出一種并行處理模式：即針對不同的信號採用不同的演算法對脈內調制信號進行分析。As a result, there are some disadvantages for its large size, heavy weight and lower efficiency. in this paper, phase - shifted zero - voltage - switching pwm converter is presented, which is help to ruduce the size and improve the efficiency of inverter. in the later stage, we adopted a pic microcomputer as the control chip, whose low price decreases the price of the inverter
在逆變環節中，本文採用體積小、功能全、價格便宜而且簡單易學的單片機pic16c72作為控制晶元，對前級直流電壓進行spwm正弦脈寬調制，從而產生了高質量的正弦輸出電壓波形，減小了輸出電壓中的諧波含量。This paper investigates the induction motor full digital ac frequency conversion system, and develops an ac motor experiment platform based on dsp tms320f240, the software and hardware implementation of the system is discussed in detail. the industry computer controls the dsp to output the space vector pulse width modulation voltage wave ( svpwm ) onto the induction motor. using this software we can view the state variable waveform on the pc and modify the variable in the dsp memory
本論文結合「基於dsp的交流電機實驗控制系統」實際科研項目，開發出基於dsp的全數字交流電機實驗控制平臺，給出了該系統平臺的軟硬體設計方案，該系統使用工控pc機對下位機dsp進行實時控制，在dsp中依據選定的電機控制策略程序，發出空間矢量脈寬調制形式的電壓波形，實現對交流電機變壓變頻控制；在上位機中能實時查看變量波形，並對dsp內存變量進行修改，在該平臺上能方便的使用軟體實現各種高性能的電機控制演算法。分享友人