大傾角上運帶式輸送機系統(tǒng)設(shè)計

大傾角上運帶式輸送機系統(tǒng)設(shè)計,傾角,上運帶式,輸送,系統(tǒng),設(shè)計 山東科技大學(xué)學(xué)士學(xué)位論文 附錄一 英文文獻(xiàn) Development of belt conveyor driving system Abstract A short review for the existing various driving methods for belt conveyor was given，which include the analysis and comparison about the advantages，disadvantages and suitable application range of these methods．Based on this the variable-frequency-control(VFC)method for belt conveyor drive was fully discussed with focus on its application in medium-high voltage range．The principle of Neutral Point Clamped (NPC)Three-Level inverters using high-voltage lGBTs together with the control strategy of rotor field-oriented vector control for induction motor drive were illustrated． Key words belt conveyor driving system，variable-frequency-control，three-level inverter. Among the methods of material conveying employed，belt conveyors play a very important part in the reliable carrying of material over long distances at competitive cost． Conveyor systems have become larger and more complex and drive systems have also been going through a process of evolution and will continue to do so．Nowadays，bigger belts require more power and have brought the need for larger individual drives as well as multiple drives such as 3 drives of 750kw for one belt (this is the case for the conveyor drives in Cheng zhuang Mine)．The ability to control drive acceleration torque is critical to belt conveyors’ performance．An efficient drive system should be able to provide smooth，soft starts while maintaining belt tensions within the specified safe limits．For load sharing on multiple drives, torque and speed control are also important considerations in the drive systems design due to the advances in conveyor drive control technology，at present many more reliable cost-effective and performance-driven conveyor drive systems.· In this paper，a short review for the existing various driving methods for belt conveyor is given in the beginning, which include the analysis and comparison bout the advantages，disadvantages and suitable application range of these methods．Based on the analysis and comparison，the variable-frequency-control(VFC) method for conveyor drive is fully discussed．VFC drives can provide excellent speed and torque control for starting conveyor belts and can also be designed to provide load sharing for multiple drives． Large belt conveyor device drivers The development of large belt conveyor exists two key questions, one is starting control problem of belt conveyor, the other one is the output power control problem. In practical use, conveyor belt is sticky elastic, long distance belt conveyor belt drive device for starting the dynamic response of the brake is a very complicated process, because of its inertia and the effect of heavy, start not smooth, starting current, the impact of electric power system and the inertia, at the moment the effect of stress changes, the instantaneous variation caused considerable bearing part dynamic load change each roller, will accelerate the damage, shorten the conveyor belt use life. Therefore, in recent years the development of large belt conveyor belt, besides improving the strength, mainly developing large belt conveyor control device. Because domestic in the design of large belt conveyor is according to analysis and calculation of the rigid body mechanics, to choose high safety coefficient of conveyor belt, generally take n = 10, investment costs, and the big difference with actual situation, still cannot meet the requirements. At present, the large belt conveyor device drivers are mainly: dc motor drives, frequency conversion, SCR motor drive device, mouse cage induction motor with torque-limiting norms or velocity modulated hydraulic coupler, liquid viscous transmission speed device etc. (1) Dc motor drives Dc motor drive speed range, adjust the smooth, overload, starting, braking torque, easy to control, high reliability, high speed, but when the high cost less energy consumption, and a brush and ring collector, using less. (2) variable-frequency-control Through the change of frequency conversion power is to change the frequency of the stator motor speed, speed range, high precision, but to corresponding solution on a series of problems with electrical and circuit system is more complex, and maintenance cost is higher, therefore, are not generally adopted. (3) Fluid Viscosity Soft Start-up Equipment Liquid viscous transmission technology is developed abroad in the 1970s, a new transmission technology, viscous clutch brake piece by changing the spacing between viscosity fluid to change the shear force to change the transmission torque. Liquid viscous governor matches with mouse cage induction motor soft starter, fluid sticky as drive system, to realize the full speed belt conveyor, smooth, and more motor start-up, reduce the load balance of electrical components and other technical requirements, improve the reliability of the belt conveyor and life-span, significant economic benefits. The working principle of the system The introduction has discussed the importance of the soft start for belt conveyor. In order to solve by soft start-up is full of belt conveyor, reduces to the influence of starting current, reduce the startup problem such as tension. Belt conveyor in soft start-up is start asking, control; ensure start-up acceleration of belt conveyor speed curve of the required rated speed until smooth startup, motor startup current and belt tension control of start within permitted. Hydraulic disaster machine as a kind of belt conveyor soft start-up device has the largest single power, to 650KW reaches 80% of soft start-up mode. It is still the main way of soft start for mine belt conveyor. The structure and function of the system In the belt drive system controlled by computer, digital control system and drive will be closed system to achieve. Feedback control is shown in figure 1, control system of main parts: SCM, digital-to-analog converters and analog-to-digital converter, keyboard and display, op-amp, sensors, communication module and actuators, etc. As part of the core chip system used to receive feedback signal, and according to the speed of calculation program, output, as the input sensor to measure the speed signal part and turn it into electrical signals, Actuator is according to the control unit of output signals required changes of driving. The structure of the system theory is shown in figure 2. Analysis on conveyor drive technologies Thanks to advances in conveyor drive control technology，nowadays many choices are available which result in more reliable, cost-effective and performance driven conveyor drive systems. Mechanical，hydraulic and electrical devices, or a combination thereof，now can be installed to provide smooth, soft starts for conveyor systems．In the following，a short review of these methods will be presented. Direct drives Full voltage starters . With a full-voltage starter design，the conveyor head shaft is direct-coupled to the motor through the gear drive．Direct full—voltage starters are adequate for relatively low—power, simple profile conveyors. With direct fu11-voltage starters, no control is provided for various conveyor loads and depending on the ratio between fu11and no-1oad power requirements，empty starting times can be three or four times faster than full load．The maintenance-free starting system is simple，low-cost and very reliable. However, they can not control starting torque and maximum stall torque；therefore．They are limited to the low-power, simple-profile conveyor belt drives . Conclusion Large foreign belt conveyor design technology has reached very high levels, have special belt conveyor belt dynamic design software, the manufacturing cost is low. For large domestic belt dynamic analysis and design is still in the stage of exploration, large belt conveyor design still press rigid theory to study, not only manufacturing cost, but can not meet the needs of practical use. So make large belt conveyor dynamic analysis and the dynamic design, can design and low cost, safe and reliable, and the conveying equipment. Therefore, the dynamic problem of belt conveyor belt directly related to the design and manufacturing technology level. Advances in conveyor drive control technology in recent years have resulted in many more reliable cost-effective and performance driven conveyor drive system choices for users．Among these choices，the variable frequency control (VFC) method shows promising use in the future for long distance belt conveyor drives due to its excellent performances．The NPC three—level inverter using high voltage 1GBTs make the variable frequency control in medium voltage applications become much more simple because the inverter itself can provide the medium voltage needed at the motor terminals，thus eliminating the step-up transformer in most applications in the past．The testing results taken from the VFC control system with NPC three-level inverters used in a 2.7km long belt conveyor drives in Chengzhuang Mine indicates that the performance of NPC three—level inverter using HV-1GBTs together with the control strategy of rotor field-oriented vector control for induction motor drive is excellent for belt conveyor driving system． Rerences 【1】 Jim Ehler. Conveyor drive technologies offer smooth，soft starts[J]．Motors& Drives．2001(4)：28—35． 【2】 Sommer R，Mertens A．Medium voltage drive system with three level NPC inverter using 1GBTs[A]．IEECo11oquium on PWM Medium Voltage Drives[C]．Birmingham．2000． 【3】 Mertens A，Sommer R，Brunotte C．Applications of medium voltage drives with 1GBT three-level inverter[A]1EE colloquium on PWM medium voltage drives [C] Birmingham，2000． 附錄二 中文譯文 帶式輸送機驅(qū)動系統(tǒng)的發(fā)展 摘要 一個簡短的評審,給出了帶式輸送機現(xiàn)有的各種驅(qū)動方法的適用范圍、優(yōu)缺點的分析和比較?；趲捷斔蜋C變頻控制的探討是全面的，并重點分析了其應(yīng)用于中高電壓的范圍。中點箝位式的原則是三級電流換向器一起用高壓lGBTs轉(zhuǎn)子磁場定向控制策略,對異步電動機的矢量進(jìn)行控制從而控制驅(qū)動。 關(guān)鍵詞 帶式輸送機驅(qū)動系統(tǒng) 變頻控制 三級電流換向器 在所有的物料輸送方法中，帶式輸送機在長距離輸送中因其經(jīng)濟可行性而起到了非常重要的作用。 輸送機系統(tǒng)已經(jīng)變得越來越大,越來越復(fù)雜，驅(qū)動系統(tǒng)也將經(jīng)歷這樣的進(jìn)化過程,并將繼續(xù)如此。現(xiàn)在，大型的帶式輸送機需要更大的能量，將需要更大的個人驅(qū)動器以及多重驅(qū)動，例如3個750KW的電機驅(qū)動一個皮帶輸送機。（這是在成莊礦對輸送機的驅(qū)動要求）能夠控制驅(qū)動力矩是控制帶式輸送機加速性能的關(guān)鍵。一個有效的驅(qū)動系統(tǒng)應(yīng)該能夠提供平滑的軟啟動，從而保持帶在特定的安全范圍內(nèi)啟動。在多重驅(qū)動為負(fù)載共享時，速度控制和扭矩也是非常重要的驅(qū)動系統(tǒng)的設(shè)計因素, 因為在輸送機驅(qū)動控制技術(shù)的進(jìn)展中目前有許多更可靠的低成本的輸送機驅(qū)動系統(tǒng)。 在這篇文章中, 在開端的一個簡短的評析，給出了帶式輸送機現(xiàn)有的各種驅(qū)動方法的比較,其中包括分析和比較了各自的優(yōu)缺點和適用范圍。根據(jù)分析和比較，帶式輸送機的變頻控制得到了充分的討論。變頻控制可提供很好的轉(zhuǎn)速和轉(zhuǎn)矩控制起動傳送帶,也可以用來為負(fù)載提供多重驅(qū)動。 大型帶式輸送機的驅(qū)動裝置 大型帶式輸送機的開發(fā)存在2個關(guān)鍵問題,一是帶式輸送機的起動控制問題,二是帶式輸送機的輸出功率控制問題。實際使用中,輸送帶是粘性彈性體,長距離帶式輸送機的輸送帶對驅(qū)動裝置起動制動的動態(tài)響應(yīng)是一個非常復(fù)雜的過程,由于其重負(fù)及慣性的影響,起動不平穩(wěn),起動電流對電網(wǎng)的沖擊較大,且在制動力、慣性力的瞬間作用下產(chǎn)生的應(yīng)力變化相當(dāng)大,瞬時變化引起各承載件的動載荷變化,會加速托輥的損壞,縮短輸送帶的使用壽命。因此,近年來對大型帶式輸送機的研制,除了提高輸送帶的強度外,主要是研制大型帶式輸送機的控制傳動裝置。由于國內(nèi)在設(shè)計大型帶式輸送機時仍按剛體力學(xué)來分析和計算,對輸送帶的安全系數(shù)選用很高,一般?。?10左右,投資成本大,且與實際情況相差較遠(yuǎn),尚不能滿足使用要求。 目前,現(xiàn)行的大型帶式輸送機的驅(qū)動裝置主要有:直流電機驅(qū)動裝置、變頻調(diào)速裝置、可控硅電動機調(diào)速裝置、鼠籠式感應(yīng)電動機配限矩型液力偶合器或調(diào)速型液力偶合器、液體粘性傳動調(diào)速裝置等幾種。 (1)直流電動機驅(qū)動裝置 直流電動機驅(qū)動裝置調(diào)速范圍廣,調(diào)節(jié)平滑,過載、起動、制動力矩大,易于控制,可靠性高,調(diào)速時能耗較少,但造價很高,且有電刷和整流子,維護(hù)量大,采用較少。 (2) 變頻控制 變頻調(diào)速是通過改變定子的供電頻率以改變電機的轉(zhuǎn)速來實現(xiàn)的,調(diào)速范圍廣,精度高,但要相應(yīng)解決電氣上帶來的一系列問題,電路系統(tǒng)比較復(fù)雜,且維修困難,造價較高,因此采用并不普遍. (3)液體粘性傳動調(diào)速裝置 液體粘性傳動技術(shù)是國外70年代發(fā)展起來的一種新型傳動技術(shù),是粘滯離合器通過改變離合片的間距達(dá)到改變粘性液體間的剪切力來改變傳遞力矩。液體粘性調(diào)速器配以鼠籠式感應(yīng)電動機,組成液粘軟起動裝置作為驅(qū)動系統(tǒng),能夠?qū)崿F(xiàn)帶式輸送機的滿速、滿載、平穩(wěn)起動、使多臺電機的負(fù)載平衡,降低對電氣及其他元部件的技術(shù)要求,提高大型帶式輸送機的可靠性和使用壽命,具有明顯的經(jīng)濟效益。 系統(tǒng)的工作原理 緒論中己經(jīng)討論了軟啟動對輸送機的重要性。采用軟啟動就是為了解決帶式輸送機必須滿載啟動，降低起動電流對電網(wǎng)的影響，減小啟動張力等問題。帶式輸送機的軟啟動就是在一定的啟動時問內(nèi)，控制啟動加速度，確保帶式輸送機按所要求的速度曲線平穩(wěn)啟動直到額定運行速度，同時電機的啟動電流和輸送帶的啟動張力控制在允許范圍內(nèi). 液力禍合器作為帶式輸送機的一種軟啟動裝置目前最大單機功率己達(dá)650KW.，占到各類軟啟動方式80%以上。仍然是我國煤礦帶式輸送機軟啟動的主要方式。 系統(tǒng)的結(jié)構(gòu)與功能 在輸送機驅(qū)動系統(tǒng)中采用微機控制，將數(shù)字電控系統(tǒng)與驅(qū)動系統(tǒng)組成閉環(huán)以實現(xiàn)反饋控制，電控系統(tǒng)主要部分組成:單片機、數(shù)模轉(zhuǎn)換器、模數(shù)轉(zhuǎn)換器、鍵盤與顯示、運放、傳感器、通信模塊及執(zhí)行器等。單片機作為系統(tǒng)的核心部分用來接收轉(zhuǎn)速反饋信號，并按設(shè)定的程序進(jìn)行計算處理，輸出結(jié)果;傳感器作為輸入部分用來測量轉(zhuǎn)速信號并將其轉(zhuǎn)化為電信號;執(zhí)行器則根據(jù)控制單元輸出的信號驅(qū)動使之按要求變化。 輸送機驅(qū)動技術(shù)的分析 多虧了輸送機驅(qū)動控制技術(shù),現(xiàn)在有許多選擇可導(dǎo)致驅(qū)動式驅(qū)動系統(tǒng)的性能和成本更可靠。機械、液壓、電氣設(shè)備,或者使他們其結(jié)合了,現(xiàn)在可以安裝提供給輸送機軟啟動、下面的這些將會呈現(xiàn)。 直接驅(qū)動 全電壓啟動,在全電壓起動設(shè)中，輸送機頭軸電機通過齒輪傳動。直接啟動是否有足夠的相對低功耗、簡單的輪廓輸送設(shè)備。不控制時提供了各種輸送荷載之間的比例,它們?nèi)Q于電力需求，空載的起動時間可以比全負(fù)荷的速度快3到4倍。免維護(hù)的起動系統(tǒng)是簡單、低成本、很可靠。然而,他們無法控制啟動的轉(zhuǎn)矩和最大的停頓扭矩。因而，它們在低能量，簡單結(jié)構(gòu)皮帶輸送機中的應(yīng)用也不廣泛。 結(jié)論 國外大型帶式輸送機的設(shè)計技術(shù)已達(dá)到很高的水平,已有專用的帶式輸送機動態(tài)設(shè)計軟件,輸送機制造成本較低。國內(nèi)對大型輸送機的動態(tài)分析和設(shè)計尚處于研究探索階段,大型帶式輸送機的設(shè)計仍按剛性理論來分析研究,不但制造成本高,而且不能滿足實際使用的需要。因此制造大型帶式輸送機需要進(jìn)行動態(tài)分析和動態(tài)設(shè)計,才能設(shè)計出既安全可靠、成本又低的輸送設(shè)備。由此可見,帶式輸送機的動態(tài)問題直接關(guān)系到輸送機的設(shè)計制造技術(shù)水平。 在最近幾年輸送機驅(qū)動控制技術(shù)的進(jìn)展,已經(jīng)導(dǎo)致許多用戶選擇更可靠的低成本和效益高的輸送機驅(qū)動系統(tǒng)。在這些選擇中，變頻控制法由于其優(yōu)良的性能在長距離帶式輸送機驅(qū)動中有廣泛的應(yīng)用前景。三級電流換向器一起用高壓lGBTs轉(zhuǎn)子磁場定向控制策略,使控制變得更加簡單,因為逆變器本身所能提供的中壓需要終端,從而消除了在過去大多數(shù)應(yīng)用的變壓器。變頻控制和三級變頻器在成莊礦2.7千米長距離帶式輸送機驅(qū)動的測試結(jié)果表明,使用HV-1GBTs三電平逆變器控制策略與轉(zhuǎn)子磁場定向矢量控制感應(yīng)電動機調(diào)速系統(tǒng)對帶式輸送機來說是很有益處的。