外文文獻(xiàn)翻譯變頻器設(shè)計(jì)使用參考

1、畢業(yè)論文(設(shè)計(jì))外文資料翻譯姓 名 學(xué) 號 年 級 專 業(yè) 系（院） 指導(dǎo)教師評語： 簽名： 年 月 日外文文獻(xiàn)及譯文Converter reference design(1) Converter Selection: Selection to determine the frequency converter when the following points: 1) The purpose of a variable frequency; constant pressure to control or constant current control. 2) the load conver

2、ter types such as leaves or pump volume pumps, with special attention to load the performance curve, the performance curve of the decision of the ways and means. 3) the frequency converter and load matching Voltage match: a rated voltage converter with a rated voltage line with the load. Current mat

3、ches: ordinary pump, the rated current inverter and motor rated current match. For special load such as deep-water pumps, and so on need to refer to the electrical performance parameters to determine the most current inverter current and Guozainengli. Torque match: in this case constant torque load

4、or slow down when the device may have occurred. 4) the use of high-speed motor drive inverter, because of the high-speed motor, anti-small, high harmonics lead to increased output current value increases. So for high-speed motor inverter Selection, its capacity to be slightly larger than the ordinar

5、y motor selection. 5) If the frequency converter to a long cable run, this time to take measures to curb the long cable to the impact of capacitive coupling, inadequate efforts to avoid converter, so in this case, the drive to enlarge the capacity of a file or the converter Output installed output r

6、eactor. 6) For the application of some special occasions, such as high temperatures, high altitude, at this time would cause the down converter capacity, the drive to enlarge the capacity of a block. (2) inverter control schematic design: 1) First confirmation of the installation environment Convert

7、er Operating temperature: high-power converter is the internal electronic components, vulnerable to the effects of temperature, product general requirements for 0 55 , but in order to ensure the safe, reliable, the use of room to be taken into account, the best control in 40 below. In the control bo

8、x, the converter box should generally be installed in the upper and strictly comply with the Manual of installation requirements, absolutely not be allowed to heating elements or components easily fever close to the converter installed at the bottom. Ambient temperature: the temperature is too high

9、and large temperature changes, within easy converter there is dew, the insulation properties will be greatly reduced, or even short-circuit caused the accident. When necessary, to be added to the desiccant in the box and heater. In water treatment, generally heavier than water vapor, if the temperat

10、ure changes, then this problem would be more prominent. Corrosive gases: the use of the environment if the corrosive gas concentrations, will not only lead corrosion of components, printed circuit boards, but it will also accelerate the aging of plastic devices, reducing insulation properties. Vibra

11、tion and shock: the control cabinet with converter by vibration and mechanical shocks will cause electrical connection is bad. Huaian thermoelectric there such a problem. Apart from raising the control cabinet at this time of the mechanical strength, vibration and shock away from the source, we must

12、 also use seismic rubber pad fixed within and outside the control cabinet, such as electromagnetic switches have a vibration components. Equipment operation after a period of time and should conduct inspections and maintenance. Electromagnetic interference: Inverter at work due to rectification and

13、frequency, produce around a lot of electromagnetic interference, these high-frequency electromagnetic waves in the vicinity of the instrument, apparatus, a certain interference. Therefore, the cabinet instrumentation and electronic systems, it should be optional metal, shielding the inverter instrum

14、ent interference. All the components should be reliable grounding, in addition, the electrical components, equipment and instrumentation should use the connectivity between the shielding control cables, and the shield should be grounded. If handled properly electromagnetic interference, often cause

15、the entire system does not work, leading to the control unit failure or damage. 2) Drives and determine the distance between the electrical cables and wiring methods Drives and motor the short distance should be as much as possible. This reduces the capacitance of the cable, reducing the emission so

16、urce of interference. Control cables optional shielded cable, power cable or optional shielding from the cable converter to use all the threads of the electrical shield. Electric cables should be independent of the other cable alignment, the minimum distance of 500 mm. At the same time should avoid

17、the electrical cables and other long-running cable lines, in order to reduce the output voltage inverter rapid changes in the electromagnetic interference. If the control cables and power cables cross, as far as possible so that they cross the 90-degree angle. Converter and analog signals on the lin

18、e and back to the main line of separation of alignment, even in the case also in the control cabinet. And the analog signal converter line the best choice of unshielded twisted pair, shielded power cables selection of the three-core cable (its specifications than ordinary electrical cables in the fi

19、les) or to comply with the user manual converter. 3) inverter control schematics Main circuit: the role of reactor is to prevent the high-frequency converter harmonic power through the input circuit to return to the grid by the impact of other electronic devices, in accordance with the capacity size

20、 converter to decide whether to increase reactor; filter Converter is installed in the output, the output of high-frequency converter to reduce harmonics, when the electrical inverter to the longer distance, we should install filters. Although the frequency converter itself has all kinds of protecti

21、on, but the lack of protection is not perfect, the main circuit breaker played overload, lack the same protection, selection, in accordance with the capacity to choose the frequency converter. Converter itself can be used to replace thermal overload protection relay. Control loop: the frequency with

22、 the frequency manually switch to the failure frequency can be manually cut-operation, not because of output voltage, frequency and frequency-be interlocked. 4) Inverter grounding Inverter correct grounding is to improve the system stability, the ability to inhibit an important means of noise. Inver

23、ter grounding resistance grounding terminal of the smaller the better, the grounding wire cross-section of not less than 4 mm, the length of not more than 5 m. Inverter should be grounded and power equipment to the sites separately, not in total. The shield signal converter from one end of the groun

24、ding end, the other floating air. Inverter and control of electrical between the same counter. (3) Inverter Control Design Converter should be installed in the control cabinet internal control counters in the design should pay attention to the following issues 1) heat: Inverter fever is the internal

25、 loss. In the frequency converter in the main part of the loss mainly to the main circuit, or about 98 percent, accounting for 2% of control circuits. In order to ensure reliable operation of the normal inverter, Thermal must inverter are usually used for cooling fan; converter fan of the contents o

26、f the converter box can be removed internal heat, if the fan does not work, should immediately stop inverter Operation; the high-power inverter also need to increase control Guishang fan, Control of the wind, to design a reasonable, all outlet into the net to set up dust, exhaust open, to avoid over

27、 the counter in a swirl, in a fixed location dust Accumulation, according to the statement converter ventilation fans to select the match, fans installed to the attention of earthquake problems. 2) the problem of electromagnetic interference Converter in its work due to rectification and frequency,

28、produce around a lot of electromagnetic interference, these high-frequency electromagnetic waves in the vicinity of the instrument, apparatus, a certain interference, and will produce high harmonics, the high harmonics will be available for adoption Xinhua loop into the whole power supply network, t

29、hus affecting other instruments. If the power inverter system as a whole lot of more than 25 percent, to be considered the anti-jamming measures to control supply. When the system in the high-frequency welding machine such as the impact load, electroplating power, the converter itself will appear as

30、 interference protection, to consider the whole system of power quality problems. 3) protection issues need to pay attention to the following points Waterproof anti-condensation: If the converter on the scene, the need to pay attention to the frequency converter Guishang not have the flange or other

31、 pipeline leak, the inverter can not be near the water splash, sum up the scene OEM Switchgear Kits & level of security to IP43 above. BOOT: All outlet into the net to set up dust debris into the barrier floc, dust network should be designed to be removable, to facilitate the clean-up, maintenance.

32、Dust of the grid network in accordance with the specific circumstances at the scene determined that dust around the net and Control Department to handle the combination of tight. Anti-corrosive gases: the chemical industry in this relatively Most of this can be on the frequency counters in the contr

33、ol room. (4) converter cable norms Signal lines and power lines must be separately alignment: the use of analog signal converter for remote control, in order to reduce the analog converter and other equipment from the interference, please control signal converter line with the strong electric circui

34、t (H Circuit-and-loop) separate alignment. Distance should be 30 cm above. Even in the control cabinet, the same connection to maintain such a standard. The signal converter and the control should not be longer than the road back to 50 m. Signal lines and power lines must be placed in different meta

35、l pipe or metal hose internal: connect PLC and the signal converter if not placed in metal tubes, Drives and vulnerable to external interference equipment; because the converter No built-in the reactor, so the converter input and output level of external power line will have a very strong interferen

36、ce, placing the signal lines of metal or metal hose has to be extended to the inverter control terminal, to ensure that the signal Line and the complete separation of power lines. 1) analog control signal line should use two-strands shielding line, cable specifications for 0.75 mm2. When the wiring

37、must pay attention to, to the extent possible, the cable Baoxian short (5-7 mm or so), while Bao Xian after the shield should wrap insulating tape to prevent shielding lines and other equipment contact with the introduction of interference. 2) To improve the simple wiring and reliability, signal rec

38、ommend the use of online video pressure bar. (5) converter and the operation of the relevant parameters set Inverter setting parameters, the parameters of each have a certain range of options, often encountered in the use of individual set of parameters for misconduct, leading converter does not wor

39、k phenomenon. Control: that is, speed control, transferred from the control, PID control or other means. To take control, according to the general control precision, the need for static or dynamic identification. Running a minimum of: that is, the minimum speed motor running, the motor running at lo

40、w speed, its poor performance cooling, electrical long run on low speed, it can cause burning motor. And at low speed, the cable will increase in the current, cable will lead to fever. The maximum operating frequency: the general maximum frequency converter to 60 Hz, and some even to 400 Hz, high-fr

41、equency will enable high-speed motor operation, which the ordinary motor, its bearings can not be over-speed long run, whether the motor rotor To be capable of such a centrifugal force. Carrier frequency: the higher the carrier frequency setting its high harmonics greater weight, and the length of c

42、able, the electrical heating, cable converter fever fever and other factors are closely related. Electrical parameters: the frequency converter to set parameters of the motor power, current, voltage, speed, maximum frequency, these parameters can be directly in the motor nameplate. FH: In a frequenc

43、y point, there may be a resonance phenomenon, particularly in the relatively high when the entire device in control of the compressor, the compressor to avoid the surge point. (6) common fault analysis 1) flow failure: over-current fault can be divided into acceleration, deceleration, constant speed

44、 over-current. May be due to the increase in frequency converter too little time to slow down, load mutations, the unequal distribution of load, output short-circuit, and other causes. At this time can be extended by the general acceleration and deceleration time, reduce the load of mutations, plus

45、braking energy components, load distribution design, the lines to be checked. If off-load converter or a failure that has been Central converter inverter circuits, to be replaced converter. 2) overload fault: overload fault, including frequency and overload the electrical overload. May be accelerate

46、d their time is too short, too low voltage power grids, Fuzaiguochong and other causes. General can be accelerated through the extension of time to extend the braking time, such as check-voltage power grid. Fuzaiguochong, selected motor and inverter can not drag the load, but also may be due to poor

47、 machinery lubrication caused. If the former is the need to replace high-power motors and inverter, if the latter will have to carry out maintenance on production machinery. 3) under-voltage: the importation of some of the power inverter that there are problems, need to check before you can run.變頻器設(shè)

48、計(jì)使用參考（1）變頻器選型：變頻器選型時(shí)要確定以下幾點(diǎn)：1) 采用變頻的目的；恒壓控制或恒流控制等。2) 變頻器的負(fù)載類型；如葉片泵或容積泵等，特別注意負(fù)載的性能曲線，性能曲線決定了應(yīng)用時(shí)的方式方法。3) 變頻器與負(fù)載的匹配問題電壓匹配：變頻器的額定電壓與負(fù)載的額定電壓相符。電流匹配：普通的離心泵，變頻器的額定電流與電機(jī)的額定電流相符。對于特殊的負(fù)載如深水泵等則需要參考電機(jī)性能參數(shù)，以最大電流確定變頻器電流和過載能力。轉(zhuǎn)矩匹配：這種情況在恒轉(zhuǎn)矩負(fù)載或有減速裝置時(shí)有可能發(fā)生。4) 在使用變頻器驅(qū)動(dòng)高速電機(jī)時(shí)，由于高速電機(jī)的電抗小，高次諧波增加導(dǎo)致輸出電流值增大。因此用于高速電機(jī)的變頻器的選型，其

49、容量要稍大于普通電機(jī)的選型。5) 變頻器如果要長電纜運(yùn)行時(shí)，此時(shí)要采取措施抑制長電纜對地耦合電容的影響，避免變頻器出力不足，所以在這樣情況下，變頻器容量要放大一檔或者在變頻器的輸出端安裝輸出電抗器。6) 對于一些特殊的應(yīng)用場合，如高溫，高海拔，此時(shí)會(huì)引起變頻器的降容，變頻器容量要放大一擋。（2）變頻器控制原理圖設(shè)計(jì)：1) 首先確認(rèn)變頻器的安裝環(huán)境工作溫度：變頻器內(nèi)部是大功率的電子元件，極易受到工作溫度的影響，產(chǎn)品一般要求為055，但為了保證工作安全、可靠，使用時(shí)應(yīng)考慮留有余地，最好控制在40以下。在控制箱中，變頻器一般應(yīng)安裝在箱體上部，并嚴(yán)格遵守產(chǎn)品說明書中的安裝要求，絕對不允許把發(fā)熱元件或易

50、發(fā)熱的元件緊靠變頻器的底部安裝。環(huán)境溫度：溫度太高且溫度變化較大時(shí)，變頻器內(nèi)部易出現(xiàn)結(jié)露現(xiàn)象，其絕緣性能就會(huì)大大降低，甚至可能引發(fā)短路事故。必要時(shí)，必須在箱中增加干燥劑和加熱器。在水處理間，一般水汽都比較重，如果溫度變化大的話，這個(gè)問題會(huì)比較突出。腐蝕性氣體：使用環(huán)境如果腐蝕性氣體濃度大，不僅會(huì)腐蝕元器件的引線、印刷電路板等，而且還會(huì)加速塑料器件的老化，降低絕緣性能。振動(dòng)和沖擊：裝有變頻器的控制柜受到機(jī)械振動(dòng)和沖擊時(shí)，會(huì)引起電氣接觸不良?；窗矡犭娋统霈F(xiàn)這樣的問題。這時(shí)除了提高控制柜的機(jī)械強(qiáng)度、遠(yuǎn)離振動(dòng)源和沖擊源外，還應(yīng)使用抗震橡皮墊固定控制柜外和內(nèi)電磁開關(guān)之類產(chǎn)生振動(dòng)的元器件。設(shè)備運(yùn)行一段時(shí)間

51、后，應(yīng)對其進(jìn)行檢查和維護(hù)。電磁波干擾：變頻器在工作中由于整流和變頻，周圍產(chǎn)生了很多的干擾電磁波，這些高頻電磁波對附近的儀表、儀器有一定的干擾。因此，柜內(nèi)儀表和電子系統(tǒng)，應(yīng)該選用金屬外殼，屏蔽變頻器對儀表的干擾。所有的元器件均應(yīng)可靠接地，除此之外，各電氣元件、儀器及儀表之間的連線應(yīng)選用屏蔽控制電纜，且屏蔽層應(yīng)接地。如果處理不好電磁干擾，往往會(huì)使整個(gè)系統(tǒng)無法工作，導(dǎo)致控制單元失靈或損壞。2) 變頻器和電機(jī)的距離確定電纜和布線方法變頻器和電機(jī)的距離應(yīng)該盡量的短。這樣減小了電纜的對地電容，減少干擾的發(fā)射源?？刂齐娎|選用屏蔽電纜，動(dòng)力電纜選用屏蔽電纜或者從變頻器到電機(jī)全部用穿線管屏蔽。電機(jī)電纜應(yīng)獨(dú)立于其

52、它電纜走線，其最小距離為500mm。同時(shí)應(yīng)避免電機(jī)電纜與其它電纜長距離平行走線，這樣才能減少變頻器輸出電壓快速變化而產(chǎn)生的電磁干擾。如果控制電纜和電源電纜交叉，應(yīng)盡可能使它們按90度角交叉。與變頻器有關(guān)的模擬量信號線與主回路線分開走線，即使在控制柜中也要如此。與變頻器有關(guān)的模擬信號線最好選用屏蔽雙絞線，動(dòng)力電纜選用屏蔽的三芯電纜（其規(guī)格要比普通電機(jī)的電纜大檔）或遵從變頻器的用戶手冊。3) 變頻器控制原理圖主回路：電抗器的作用是防止變頻器產(chǎn)生的高次諧波通過電源的輸入回路返回到電網(wǎng)從而影響其他的受電設(shè)備，需要根據(jù)變頻器的容量大小來決定是否需要加電抗器；濾波器是安裝在變頻器的輸出端，減少變頻器輸出的

53、高次諧波，當(dāng)變頻器到電機(jī)的距離較遠(yuǎn)時(shí)，應(yīng)該安裝濾波器。雖然變頻器本身有各種保護(hù)功能，但缺相保護(hù)卻并不完美，斷路器在主回路中起到過載，缺相等保護(hù)，選型時(shí)可按照變頻器的容量進(jìn)行選擇?？梢杂米冾l器本身的過載保護(hù)代替熱繼電器?？刂苹芈罚壕哂泄ゎl變頻的手動(dòng)切換，以便在變頻出現(xiàn)故障時(shí)可以手動(dòng)切工頻運(yùn)行，因輸出端不能加電壓，固工頻和變頻要有互鎖。4) 變頻器的接地變頻器正確接地是提高系統(tǒng)穩(wěn)定性，抑制噪聲能力的重要手段。變頻器的接地端子的接地電阻越小越好，接地導(dǎo)線的截面不小于4mm，長度不超過5m。變頻器的接地應(yīng)和動(dòng)力設(shè)備的接地點(diǎn)分開，不能共地。信號線的屏蔽層一端接到變頻器的接地端，另一端浮空。變頻器與控制柜之間電氣相通。（3）變頻器控制柜設(shè)計(jì)變頻器應(yīng)該安裝在控制柜內(nèi)部，控制柜在設(shè)計(jì)時(shí)要注意以下問題1) 散熱問題：變頻器的發(fā)熱是由內(nèi)部的損耗產(chǎn)生的。在變頻器中各部分損耗中主要以主電路為主，約占98%，控制電路占2%。為了保證變頻器正常可靠運(yùn)行，必須對變頻器進(jìn)行散熱我們通常采用風(fēng)扇散熱；變頻器的內(nèi)裝風(fēng)扇可將變頻器的箱體內(nèi)部散熱帶