current harmonics 中文意思是什麼

current harmonics 解釋
電流諧波
  • current : adj. 1. 通用的,流行的。2. 現在的,現時的,當時的。3. 流暢的;草寫的。n. 1. 水流;氣流;電流。2. 思潮,潮流;趨勢,傾向。3. 進行,過程。
  • harmonics : n. 【音樂】和聲學。
  1. Because of the elements which run under nonideal linearity and unentire symmetry in the power system, the loads which are different and change randomly, the methods which adjust and control the system faultily and operate improperly, the disturbance and the malfunction which happen somewhere, the current and voltage in the supply system are distorted seriously and thus large amount of harmonics are produced

    但是,由於電力系統元件運行的非理想線性或非完全對稱、負載的性質各異且隨機變化、調控手段的不完善以及錯誤操作、外來干擾和各種故障的存在,供電網中的電流(電壓)發生畸變,產生大量諧波。
  2. Firstly, in spherical coordinate system, the sovp formulation for the time - harmonic electromagnetic fields of the current dipole in conductive infinite - space is derived, using reciprocity theorem and transforming relations between special functions. then, selecting appropriate coordinate system, using superposition principle, the boundary - value problem of modified magnetic vector potential on the problem of a time - harmonic current dipole in spherical conductor is solved and analytical solution is obtained. finally, by means of the addition formulas of legendre polynomial and spherical harmonics function of degree n and order 1, the analytical solution in spherical coordinate system specially located is transformed into that in spherical coordinate system arbitrarily located

    首先利用特殊函數間的轉化關系和互易定理推導得到了無限大導體空間中球坐標下時諧電流元電磁場的二階矢量位形式:然後利用疊加原理,選擇合適坐標系,求解了導體球中時諧電流元的修正磁矢量位邊值問題,得到了問題的解析解;最後依據不同坐標系下電磁場解的轉化原理,藉助勒讓德多項式和n次1階球諧函數的加法公式,將坐標系特殊安放時的電磁場解析解變換到坐標系一般安放時的解析解,給出了球內電場和球外磁場的並矢格林函數。
  3. There is great change of negative current component when it happens the line - open fault. it is marked as the occurrence of the fault. and it can be concluded the phase characteristic of negative current in the line. in the transient course, there are plenty of harmonics in the fault line. through the transient analysis, it is drawed that the amplitude of each harmonic in fault phase is greater than other phases. harmonic current in fault line is far greater than other normal lines

    發生斷線故障以後,線路中會出現負序電流的突變,可以作為故障啟動判斷的標志,並且通過分析得出了故障時負序基波電流的相位特點。在故障暫態過程中,故障電流中含有大量豐富的諧波成分,各次諧波在故障期間有突變,並且衰減很快。
  4. The way of taking one nth out of capacitor ' s the first harmonic capacitive reactance as its nth harmonic impedance is verified whit the data from tang7c. according to the approximately estimating method, the first harmonic impedance of 220kv system is calculated. on the basis of the models, this paper gives the harmonic equivalent circuit of substation and gives the b ( n ) function of the harmonic time n. when the capacitors has different combination, b ( n ) ' s value will also change, with the inputting local measurement data, the paper studies the series and parallel resonance at the substation, and deduces that the reason the capacitor ' s fuse of tang6c is frequently interrupted is that its capacitor current contains a large number of 5th harmonics, and that the reason the discharging pt of tang7c capacitor being exploded is also that the 7th and 9th harmonic currents are amplified

    據此,對該站進行了串聯諧振分析和並聯諧振分析,並結合測試數據和有關變電站的運行記錄,指出了導致該站電容器湯6c頻繁燒保險的主要原因是5次諧波電流含量偏高,引起湯7c放電pt爆炸也是因為7次和9次諧波電流被放大。針對這些導致湯陰變電站補償電容器故障的原因,提出了相應的諧波治理措施,包括針對湯6c電容器5次諧波電流含量偏高的原因,提出了停運湯6c電容器或者通過把湯sc電容器的部分容量併入湯6c電容器(湯sc其餘部分停運)以增加湯6c諧波承受能力的措施;針對# 2變低壓側7次和9次諧波電流被放大的現象,提出了在湯7c電容器上加裝一定百分比的串聯電抗器的措施。
  5. 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。
  6. This paper makes a science analysis to power system " s harmonics and harmonic oscillation in partial power net, develop the analysis software of harmonic oscillation characteristic. make use of this software can obtain the harmonic oscillation characteristic curve in a row frequency range, can discover accurately oscillation, can make an in - depth analysis and statistics and renew the realistic curve of voltage or current on the basis of the measured - data

    本文通過對電力系統諧波及局域電網諧波諧振現象的理論分析,設計、開發了局域電網諧波諧振特性分析軟體,利用該軟體可以獲取連續頻域內的諧波諧振特性曲線,發現準諧振區域,而且還能根據實際測試數據,正確統計分析出所要求的參數,同時能夠恢復電網實際的電壓、電流波形,並能根據國家標準自動生成分析報告。
  7. To reduce the harmonics in the line current, the random pwm mode is adapt. related to the typically constant pwm carrier frequency and its high harmonics, modulation of this frequency can be used to decrease emi and cost no more gain

    為了抑制輸入電流中一些幅值較大的諧波成分,利用dsp控制的特點,電路採用了隨機pwm方式,在不增加系統成本的前提下,有效地抑制了輸入電流的高次諧波含量。
  8. This paper focuses on the control strategies to improve the performance of the three - phase ac - dc pwm voltage - source - converters ( vsr ) under unbalanced power supply. the problems such as negative sequences current, voltage and current harmonics and un - constant ( un - smooth ) power flow from ac to dc side are discussed in this paper. the analytical solutions for negative sequence current and harmonic current elimination are obtained by fully feed - forward of negative sequence voltage and producing a non - harmonic current command of the inner - loop

    電網不平衡時,基於電網平衡為約束條件設計的三相vsr將出現不正常運行狀態,比如三相vsr交流電流中出現負序分量,使交流電流嚴重不對稱;直流電壓和交流電流中出現非特徵諧波分量,使直流電壓和交流電流波形發生嚴重畸變;三相vsr從電網吸收不平衡的瞬時功率等一系列問題。
  9. Harmonics, reactive power, voltage flicker and negative - sequence current of power grids can affect the power quality and harm the power equipment badly

    摘要電網中存在諧波、無功、電壓閃變及負序電流等問題,嚴重影響電能質量,危害電力設備。
  10. Secondly the detection precision is only related to the synchronization phase but not to the amplitude of the mainline voltage because that it uses the optimized pulses synchronous with the mainline voltage as modulation signals. thirdly it decreases the requirement of the input low pass filter and eliminates the error resulting from the direct component and even harmonics of load current. the most significant merit is that it can eliminate the effect of a few low order odd harmonics and the detecting circuit is easy to be implemented

    模擬和實驗結果表明該方法的主要優點有:不需使用乘法器進行信號調制,調制信號採用與電網電壓同步的優化特定脈沖,其檢測精度只與同步相位有關,而與電網電壓幅值無關;降低了對輸入低通濾波器的通頻帶要求,直流和偶次諧波分量對檢測精度沒有影響;突出的優點是可以消除有限個低奇次諧波對檢測結果的影響。
  11. Realization of detecting current harmonics theory based on the instantaneous reactive power in dsp

    基於瞬時無功理論的電流諧波檢測演算法實現
  12. Also a prototype for the boost two - level converter is built. the experimental results show that the boost tl converter has lower input current harmonics than the boost two - level converter, and it can satisfy the limits specified in rtca do - 160d. so the boost tl converter has the potential to apply in the future variable frequency ac airborne system ranged from 360hz to 800hz

    並完成一臺boostpfc變換器進行實驗對比,實驗結果表明,相比于boostpfc變換器, boosttlpfc變換器能有效地減小電流諧波使其滿足相應的諧波標準rtcado - 160d ,所以它適合於即將採用360hz - 800hz變頻交流供電體制的航空電網。
  13. With promulgation and obliging actualization of iec 1000 - 3 - 2 etc. international standards, power factor correction ( pfc ) technique become a hotspot of research in power electronics field. based on average current mode, the paper introduce the design and implementation of a fully digital controlled single - phase boost power factor corrector with fast response. the control - loop circuit is realized using digital control and the corrector can tend to unity power factor, lower current harmonics and high transfer efficiency

    本文在平均電流模式控制的有源功率因數校正技術的基礎上,設計了一種控制電路基於數字信號處理器( dsp ) 、主電路採用boost變換器拓撲結構的全數字單相功率因數校正器,用數字電路代替傳統的模擬電路來實現對整個迴路的控制,最終使得校正器具有輸入功率因數接近於1 、低電流諧波以及高轉換效率的特性。
  14. The operating principles of svpwm and associated control algorithms are also covered in the paper. by using svpwm to control the magnitude and phase angles of the spatial voltage vector, the speed control of the drive system in this paper can reduce the output of current harmonics, lower the torque ripple, and improve the energy efficiency

    本文還對svpwm的工作原理和控制演算法進行了研究,控制系統採用svpwm演算法,通過對空間電壓矢量的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。
  15. Combined active power filter and reactive power filter make up hybrid active power filter which not only reduce the cost but also have good harmonics compensation effect, so hybrid active power filter reaches a practical purpose. the paper introduces the concept of harmonics 、 its harm to power grid and limitation of harmonics voltage and current harmonics, and it also demonstrates the necessity of eliminate harmonics, and briefly introduces several methods to eliminate harmonics and research of both here and abroad

    將有源電力濾波器與無源電力濾波器相結合,構成混合有源濾波器,取兩者之長,補兩者之短,既可以降低諧波補償系統的成本,也可以有良好的諧波補償效果,從而達到混合有源濾波器實用的目的。
  16. As a result of employing multilevel phase - shifted method with zig zag connection in transformer secondary, in the primary the current harmonics their orders are lower than 6m 1 are eliminated ( m is the number of power cell each phase ). in the inverter side because of using pulse shifting pwm control, the equivalent switch frequency of output is m times as high as one h - bridge, so the output voltage waveform of the inverter is near sine with less harmonics

    對于整流電路,由於採用變壓器移相多重化整流,在理論上可以實現曲折變壓器一次繞組中低於6m 1次諧波電流相互抵消( m為串聯單元個數) ;對于逆變電路,由於採用移相pwm控制方式,等效開關頻率提高m倍,因此輸出電壓接近正弦波,諧波含量較小。
  17. In order to solve this problem, the power factor correction ( pfc ) pre - regulators are applied to limit the input current harmonics of the switching power supplies

    為了限制諧波污染,用電設備需加入功率因數校正( powerfactorcorrection , pfc )裝置。
  18. The standard bi - state magnetic bearing amplifier have some disadvantages such as high current harmonics, low reliability and the current mode switching for tri - state amplifier is expounded. the ba

    從降低系統成本和提高可靠性的角度,提出了一種採用空間電壓矢量控制的開關功率放大器,對其進行了模擬研究,指出了這種功放的應用前景。
  19. As the most effective means to eliminate current harmonics, active power filer ( apf ) can compensate dynamically harmonics whose frequencies and amplitudes vary ; moreover, its compensation characteristics is immune to the impedance variation of utility

    有源電力濾波器是抑制電網諧波的有效措施之一,這種濾波器對頻率和幅度都變化的諧波進行跟蹤補償,且補償特性不受電網阻抗的影響,因而受到了廣泛的重視。
  20. The current harmonics it produces deteriorate the quality of the power source, which eventually affect the other equipment. in order to solve this problem and meet the requirement for standards, such as iec 555 - 2, iec 1000 - 10 - 3 - 2, ieee 519, and iec 6100 - 3 - 2, a lot of power - factor - correction circuits, as the best way to improve power quality, have been developed

    所產生的諧波污染了電源的質量,並最終干擾其它電氣設備的正常工作,為了解決這一問題以滿足諸如iec555 - 2 、 iec1000 - 10 - 3 - 2 、 ieee519 、和iec6100 - 3 - 2等標準的要求,許多功率因數校正變換器作為解決這一問題的最佳方法被研製出來了。
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