脈波頻率調變 的英文怎麼說
中文拼音 [màibōbīnlǜdiàobiàn]
脈波頻率調變
英文
pulse-frequency modulation (pfm)- 脈 : 脈名詞1. (動脈和靜脈的統稱) arteries and veins2. (脈搏的簡稱) pulse 3. (像血管的組織; 連貫成系統的東西) vein
- 波 : Ⅰ名詞1 (波浪) wave 2 [物理學] (振動傳播的過程) wave 3 (意外變化) an unexpected turn of even...
- 頻 : Ⅰ形容詞(次數多) frequent Ⅱ副詞(屢次) frequently; repeatedly Ⅲ名詞1 [物理學] (物體每秒鐘振動...
- 率 : 率名詞(比值) rate; ratio; proportion
- 調 : Ⅰ動詞1 (配合得均勻合適) harmonize; suit well; fit in perfectly 2 (使配合得均勻合適) mix; adju...
- 頻率 : frequency; rate
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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 main circuit is consisted of 18 thyristors circuit and protection circuit. with the help of control subsystem, it can get the output of low frequency voltage ( current ) with the shape of sine wave ; the core of the control subsystem is the cpu of 87c196kc, and the synchronization circuit, the pulse - widen circuit, and the power - enlarged circuit form the accessorial subsystem of the control system. it possesses all the functions of digital triggering, digital tuning, analog / digital conversion ; the input transfer can isolate the input and output ; and the circumfluence reactor can reduce the circumfluence
主迴路採用由18個晶閘管組成的三相零式電路,並輔以晶閘管的保護電路,通過控制可以得到低頻正弦波的電壓(電流)輸出;控制迴路主要以87c196kccpu為核心,其外圍電路包括同步電路,脈沖拓寬電路,功率放大驅動電路等,完成了數字觸發、數字調節、模數轉換等功能;進線電源變壓器具有變壓和隔離作用;環流電抗器則實現了有效抑制主迴路瞬時脈動環流的功能。Due to the complexity of the structure and control of cycloconverter - type three - phase hf link inverter for soft - switching based on phase - shift - controlled full - bridge mode, a simple and optimized vvvf control strategy is proposed. this control strategy includes : produced pwm by space voltage vector ( svm ) and equivalent carrier frequency fe = 1 / te are introduced into the pdm control of the cycloconverter ; softened equivalent pwm wave is generated at the notches of hf voltage pulses ; the harmonious control between regulating pulse width by phase - shifted angle and regulating voltage of equivalent pwm is to minimize the harmonics content of output voltage of the inverter
西安理工大學博士學位論文針對這種前級移相全橋軟開關周波變流型三相高頻鏈逆變器結構和控制的復雜性,提出了一種實現簡單而整體優化的vvvf控制策略:將空間電壓矢量產生p姍的方法svm和等效載波頻率fe = 1 / te引入到周波變流器的pdm控制;按高頻電壓脈沖前後沿軟化等效p翎波;用移相調節高頻脈沖寬度和等效p姍調壓協調控制逆變器輸出電壓,在滿足輸出電壓條件下使諧波最小。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。In this part the signal from the infrared sensor was amplified by common collector amplifier, and the demodulator was built by filter. in which the signal got demodulated. because we just need the frequency of the signal, filter may achieved
通過信號通路,傳感器生成的調幅波信號轉變為與脈搏頻率相同的方波。先由運算放大器接共集電極電路完成信號放大,通過濾波得到脈搏信號的頻率,從而用濾波器電路完成了解調功能。Then the pulse is modulated by pwm. after the modulated signal through a low pass filter, we can get the change of the frequency that related to the capacitor
對頻率變化的脈沖進行寬度調制,通過低通濾波就可以輸出頻率變化量,也就可以得到相應的加速度值。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 ) 。Some valuable conclusions are summarized by theoretical analysis and simulation experiments : from the side of signal processing, pulse jamming can be deleted by the method of time - domain sliding window accumulation and can be restored by interpolative prediction. ; gauss white nose can be attenuated while jamming disperse point - target by the method of time - frequency analysis in time - frequency domain. ; radio frequency noise jamming can be deleted by the method of average range frequency spectrum and notching in frequency domain
通過大量的理論分析和模擬實驗,得到了一批具有一定價值的結論:從信號處理的角度出發,對于脈沖式干擾,能夠運用時域滑動窗口積累的方法去掉,並且通過預測插值得到較好的恢復;對于高斯白噪聲干擾,在時頻變換域內應用時頻分析方法可減小其對分散點目標的干擾;對于射頻噪聲,通過平均距離頻頻法和頻域陷波的方法可以去掉;從改變合成孔徑雷達系統角度出發,類似雙基地雷達能夠避免各種干擾,對發射信號進行調幅,調相以及改變調頻斜率都是較好的抗干擾方法。For ac discrete digital signal, the zero - calculating method is applied to calculate the true zero in the periodic signal. for the measurement of ac and dc voltage spectrum, the faster fourier transform ( fft ) is used. to measure dc voltage ripple spectrum and frequency modulation of ac voltage, the digital filter is used
其中對于交變的離散數字量,採用零點撿出技術計算周波信號的真實過零點;對于交直流電壓頻譜,採用快速傅立葉變換進行頻譜分析;對于直流電壓脈動和頻率調制,採用數字濾波器進行濾波后再做分析處理。These illuminate that voltage vector control of a low power tow phase inverter - fed induction motor driver as a pulse width modulation control of a two - phase inverter - fed induction motor driver system can effectively cancelled the low harmonic and improve the system performance
相對于方波等其它供電方式的控制,採用電壓空間矢量技術在小功率兩相異步電動機的變頻調速控制上的應用可使轉矩脈動減少,效率提高,具有一定的經濟性和實用性。Then on one hand, author makes researches of anti - jamming against pulse jamming 、 gauss white noise jamming and radio frequency noise jamming from the side of signal processing. author exercises much signal processing knowledge of time - domain sliding window accumulation 、 wavelet analysis 、 time - frequency analysis and linear prediction and carries out many simulation experiments. on the other hand, author proposes the anti - jamming methods of using a sar similar to double - base radar and modulating the amplitude 、 the phase of emission signal and changing the frequency modulation slope from the side of changing sar system model
作者首先提出了合成孔徑雷達抗干擾的定義、分類以及評價抗干擾方法好壞的主客觀標準;然後,一方面從信號處理的角度出發對脈沖式干擾、高斯白噪聲干擾以及射頻噪聲干擾進行了抗干擾研究,其中運用了時域滑動窗口積累,小波分析,時頻分析以及線性預測等信號處理知識,做了大量的模擬實驗;另一方面,本文基於改變合成孔徑雷達系統模式提出了利用類似雙基地雷達來抗干擾,以及對發射信號進行調幅、調相以及改變調頻斜率來抗干擾,同樣做了相應的模擬實驗。According to the following design theory : the dsp calculates in real time and produces three phases spwm waves to control the on or off of the 6 igbts in ipm respectively. ipm then inverts the commutated single phase direct current ( insulated gate bipolar transistor ) into three phases alternating current. when modulated signals of spwm are changed, the on - off time of switches also changes, so as to the voltage and frequency of output signals
本文提出了一種基於dsp (數字信號處理器tms320f240 )的通用的三相間接變頻電源系統,利用分段同步調製法和混合查表法,實時計算不同頻率下的采樣周期、電壓幅值、輸出脈寬,產生雙極性spwm波形,經驅動放大後用于ipm ( intelligentpowermodule )中的絕緣柵雙極型晶體管柵級驅動,以控制電源的輸出電壓和頻率,實現變頻電源的智能數字控制。The list betterments aimed at the properties of system : through the testing of dc voltage, pulse width and inverting voltage and frequency can be regulated online to fit for different steady load ; reducing speed ripples by compensating with nonzero voltage working proportional time ; adopting the technology of harmonics suppression. as a result, the high precision and wide speed control is realized and the step out is overcome
針對系統的性能指標,做了如下改進:對直流側電壓的檢測,在線調整逆變器導通脈寬、輸出電壓和頻率,可以適應不同大小的恆負載;並用非零電壓矢量作用時間進行補償的方法,減小電機的低速脈動;加入了諧波抑制技術等。分享友人