防恐電子擋車器設計——擋車器總體及控制系統(tǒng)設計

防恐電子擋車器設計——擋車器總體及控制系統(tǒng)設計,防恐電子擋車器設計——擋車器總體及控制系統(tǒng)設計,電子,擋車,設計,總體,整體,控制系統(tǒng) 南京理工大學泰州科技學院 畢業(yè)設計(論文)外文資料翻譯 系　　部： 機械工程系 專 業(yè)： 機械工程及自動化 姓 名： 王鋒 學 號： 0501510137 外文出處： Michael L. Nave, P.E.1989. 附 件： 1.外文資料翻譯譯文；2.外文原文。 指導教師評語： 該譯文大體正確地表達了原文意思，敘述條理清楚，語句通順，翻譯質量達到規(guī)定的要求，專業(yè)術語譯文有些還不夠準確。 簽名： 2009年 3月 18日 注：請將該封面與附件裝訂成冊。 附件1：外文資料翻譯譯文 煤礦業(yè)帶式輸送機幾種軟起動方式的比較 運行帶式運送機的動力必須由驅動滑輪產生，通過滑輪和傳送帶之間的摩擦力來傳遞。為了傳遞能量，傳送帶上面的張力在接近滑輪部分和離開滑輪部分必定存在著差別。這種差別在穩(wěn)定運行、啟動和停止時刻都是真實存在的。傳統(tǒng)傳送帶結構的設計，都是根據穩(wěn)定運行情況下傳送帶的受力情況。因為設計過程中沒有詳盡研究傳送帶啟動和停止階段的受力情況，所有的安全措施都集中在穩(wěn)定運行階段（Harrison 1987）。本文主要集中講述傳送機啟動和加速階段的特性。傳送帶設計者在設計時必須考慮控制啟動階段的加速狀況，以免使傳送帶和傳送機驅動系統(tǒng)產生過大的張力和動力（Suttees，1986）。大加速度產生的動力會給傳送帶的紋理、傳送帶結合處、驅動滑輪、軸承、減速器以及耦合器帶來負面影響。毫無控制的加速度產生的動力能夠引起帶式傳送機系統(tǒng)產生諸多不良問題，比如上下曲線運動、過度傳送帶提升運動、滑輪和傳送帶打滑、運輸原料的溢出和傳送帶結構。傳送帶的設計需要面對兩個問題：第一，傳送帶驅動系統(tǒng)必須能夠產生啟動帶式傳送機的最小轉動力矩；第二，控制加速度產生動力在安全界限內。可以通過驅動力矩控制設備來完成，控制設備可以是電子手段也可以是機械手段，也可以是兩者的組合（CEM，1979）。 本文主要闡述輸送機的開始和加速的過程。傳送帶設計師必須控制開始加速度防止過度張緊在傳送帶織品和力量在皮帶傳動系統(tǒng)。強加速度力量可能有害地影響傳送帶織品，傳送帶接合，驅動皮帶輪，更加無所事事的滑輪,軸,軸承, 速度還原劑, 并且聯結。未管制的加速度力量可能造成皮帶輸送機有垂直的曲線的系統(tǒng)性能問題,傳送帶緊線器運動, 驅動皮帶輪摩擦損失, 材料溢出, 并且做成花彩傳送帶織品。傳送帶設計員與二個問題被面對, 皮帶傳動系統(tǒng)必須導致極小的扭矩足夠強有力開始傳動機, 和控制了這樣加速度強制是在安全限額內。光滑開始傳動機可能由對驅動器扭矩控制設備的用途, 或機械或電子, 或組合的二完成(CEM 1979) 。 什么是最佳的皮帶輸送機驅動系統(tǒng)? 答案取決于許多變量。最佳的系統(tǒng)是一個為開始, 運行, 和終止提供可接受的控制在合理的費用和以及高可靠性。皮帶傳動系統(tǒng)為本文我們考慮的設計方案, 皮帶輸送機被電子頭等搬家工人幾乎總驅動。傳送帶"驅動系統(tǒng)" 將包括多個要素包括電子原動力、電子馬達起始者以控制系統(tǒng), 馬達聯結、速度還原劑、低速聯結、皮帶傳動滑輪、和滑輪閘 (Cur 1986) 。它重要, 傳送帶設計員審查各個系統(tǒng)要素的適用性對特殊申請。為本文的目的, 我們假設, 所有驅動系統(tǒng)要素設置礦的新鮮空氣, 非允許, 面積,全國電子編碼, 條款500 防爆, 礦的表面的面積。皮帶傳動要素歸因于范圍。某些驅動器要素是可利用和實用的用不同的范圍。為這論述, 我們假設那皮帶傳動系統(tǒng)范圍從分數馬力對千位的多個馬力。小驅動系統(tǒng)經常是在50 馬力以下。中型系統(tǒng)范圍從50 到1000 馬力。大型系統(tǒng)可能被考慮在1000 馬力之上。范圍分部入這些組是整個地任意的。必須被保重抵抗誘惑對超出馬達或在馬達之下傳送帶飛行提高標準化。驅動器結果在粗劣的效率和在高扭矩的潛在,當驅動器能導致破壞性超速在再生,或過度加熱以變短的馬達壽命。扭矩控制。傳送帶設計員設法限制開始的扭矩到沒有比150%運行中。限額在應用的開始的扭矩經常是傳送帶胴體肉、傳送帶接合、滑輪絕熱材料,軸偏折評級。在更大的傳送帶和傳送帶以優(yōu)化大小的要素, 扭矩限額110%至125%是公用。除扭矩限額之外, 傳送帶起始者必需限制會舒展圍繞和會導致旅行的波浪的扭矩增量。一個理想的開始的控制系統(tǒng)會適用于資格整個傳送帶的扭矩傳送帶休息由問題的脫離決定, 或運動, 然后扭矩相等與傳送帶的運動需求以負荷加上恒定的扭矩從休息加速系統(tǒng)要素的慣性對最終奔跑速度。這使系統(tǒng)臨時強制和傳送帶舒展。不同的驅動系統(tǒng)陳列變化的能力控制扭矩的申請對傳送帶休息和以不同的速度。并且, 傳動機陳列裝載二個極端。一條空傳送帶正常存在最小的必需的扭矩為脫離和加速度, 當一條充分地被裝載的傳送帶存在最高的必需的扭矩。開采驅動系統(tǒng)必須是能稱應用的扭矩從一個2/1 比率為一個水平的簡單傳送帶安排, 對一個10/1 范圍為一個傾斜、復雜傳送帶配置文件。 各個驅動系統(tǒng)將要求一個控制系統(tǒng)調控開始的機制。 最共同的類型控制被使用在更小對中等大小驅動以簡單的外形被命名“開環(huán)加速度控制” 。 在開環(huán), 控制系統(tǒng)早先被配置程序化開始的機制以被規(guī)定的方式, 通常準時根據。 在開環(huán)控制, 駕駛使用參數譬如潮流,扭矩,或速度不影響序列操作。這個方法假定, 控制設計師充分地塑造了驅動系統(tǒng)表現在傳動機。為更大或更加復雜的傳送帶,“閉合回路”或“反饋”控制可以他運用了。在閉合回路控制, 在開始期間, 控制系統(tǒng)顯示器通過傳感器駕駛使用參數譬如馬達的當前層, 傳送帶的速度, 或力量在傳送帶, 并且修改起動程序控制,極限,或優(yōu)選或佩帶了參量。閉合回路控制系統(tǒng)修改開始的被應用的力量在一臺空和充分地被裝載的傳動機之間。 常數在數學模型與被測量的可變物有關對系統(tǒng)驅動反應被命名定調的常數。 這些常數必須適當地被調整為成功的應用對各臺傳動機。 最共同的計劃為傳動機開始閉合回路控制是車頭表反饋為速度控制和壓電池力量或驅動力反饋為扭矩控制。在一些復雜系統(tǒng), 它是中意安排閉合回路控制系統(tǒng)調整自己為各種各樣的遇到的傳動機情況。這被命名“能適應的控制” 。這些極端可能介入浩大的變異在裝貨,圍繞的溫度,裝貨的地點在外形, 或多個驅動選擇在傳動機。有三個共同的能適應的方法。介入決定做在開始之前,如果控制系統(tǒng)能知道傳送帶是空的,它會減少最初的力量和會加長加速度力量的應用對最高速度。如果傳送帶被裝載, 控制系統(tǒng)會應用資格力量在攤位之下使較少時刻和供應充足的扭矩及時地充分地加速傳送帶。因為傳送帶只成為了裝載在早先賽跑期間由裝載驅動, 平均驅動潮流可能被抽樣當連續(xù)和被保留在反射傳送帶搬運器時間的緩沖記憶。然后在停工平均也許是預先處理一些開環(huán)和閉合回路為下個開始。第二個方法介入根據驅動觀察發(fā)生在最初開始或“行動期間證明”的決定。這及時驅動潮流的或力量通常介入比較對傳送帶速度。如果驅動潮流或力量必需及早在序列是降低并且行動被創(chuàng)始, 傳送帶必須被卸載。如果驅動潮流或力量必需是高的。在開始, 傳動機必須被裝載。這個決定可能被劃分在區(qū)域和使用修改起動程序控制的中部和結束。 第三個方法介入傳送帶速度的比較對時刻為這個開始反對傳送帶加速度歷史極限, 或“加速度信封監(jiān)視”。在開始, 傳送帶速度被測量對時間。這與被保留在控制系統(tǒng)記憶的二限制的傳送帶速度曲線比較。第一曲線描出空的傳送帶加速, 并且第二個充分地被裝載的傳送帶。因而,如果當前的速度對時間比被裝載的外形低,它也許表明,傳送帶被超載,妨礙,或驅動故障。如果當前的速度對時間比空間的外形高級,它也許表明一條殘破的傳送帶結合或驅動故障。 無論如何，當前的起飛中止并且警報運行。 最好的傳送帶啟動系統(tǒng)要求在不同的傳送帶負載條件下，能夠以合理的代價帶來可靠性高的可以接受的運行性能。但是至今沒有一個啟動系統(tǒng)能夠達到這樣的要求。傳送帶設計者必須為每個傳送帶設計啟動系統(tǒng)屬性。總得來說，全電壓交流發(fā)動機啟動適合于簡單結構的小型傳送帶。減電壓SCR交流發(fā)動機啟動是地下中、小型傳送帶的基本啟動方法。最新的進展顯示，固定液體填充耦合系統(tǒng)的交流發(fā)動機是簡單結構中、大型傳送帶基本啟動方法。對于那些大、中型而且需要重復啟動的復雜結構傳送帶，繞線轉子發(fā)動機驅動是常用的選擇。在結構特別復雜，運行需要不同速度的傳送帶啟動中，傳送帶直流發(fā)動機驅動、不同填充液體驅動、和相異機械傳遞驅動系統(tǒng)一直實力相當的候選者。具體選擇哪個啟動方式由使用環(huán)境，相對價格，運行能耗，反應速度和使用者習慣來決定。變頻交流驅動和非電刷直流驅動主要限制于中型傳送帶，這些中型傳送帶需要精確的速度控制，高代價和復雜性。但是，隨著持續(xù)的競爭和技術進步，波形綜合技術的電子驅動器的使用將越來越廣。 附件2：外文原文 A Comparison of Soft Start Mechanisms for Mining Belt Conveyors The force required to move a belt conveyor must be transmitted by the drive pulley via friction between the drive pulley and the belt fabric. In order to transmit power there must be a difference in the belt tension as it approaches and leaves the drive pulley. These conditions are true for steady state running, starting, and stopping. Traditionally, belt designs are based on static calculations of running forces. Since starting and stopping are not examined in detail, safety factors are applied to static loadings (Harrison, 1987). This paper will primarily address the starting or acceleration duty of the conveyor. The belt designer must control starting acceleration to prevent excessive tension in the belt fabric and forces in the belt drive system (Suttees, 1986). High acceleration forces can adversely affect the belt fabric, belt splices, drive pulleys, idler pulleys, shafts, bearings, speed reducers, and couplings. Uncontrolled acceleration forces can cause belt conveyor system performance problems with vertical curves, excessive belt take-up movement, loss of drive pulley friction, spillage of materials, and festooning of the belt fabric. The belt designer is confronted with two problems, The belt drive system must produce a minimum torque powerful enough to start the conveyor, and controlled such that the acceleration forces are within safe limits. Smooth starting of the conveyor can be accomplished by the use of drive torque control equipment, either mechanical or electrical, or a combination of the two (CEM, 1979). What is the best belt conveyor drive system? The answer depends on many variables. The best system is one that provides acceptable control for starting, running, and stopping at a reasonable cost and with high reliability (Lewdly and Sugarcane, 1978). Belt Drive System For the purposes of this paper we will assume that belt conveyors are almost always driven by electrical prime movers (Goodyear Tire and Rubber, 1982). The belt "drive system" shall consist of multiple components including the electrical prime mover, the electrical motor starter with control system, the motor coupling, the speed reducer, the low speed coupling, the belt drive pulley, and the pulley brake or hold back (Cur, 1986). It is important that the belt designer examine the applicability of each system component to the particular application. For the purpose of this paper, we will assume that all drive system components are located in the fresh air, non-permissible, areas of the mine, or in non-hazardous, National Electrical Code, Article 500 explosion-proof, areas of the surface of the mine. Belt Drive Component Attributes Size. Certain drive components are available and practical in different size ranges. For this discussion, we will assume that belt drive systems range from fractional horsepower to multiples of thousands of horsepower. Small drive systems are often below 50 horsepower. Medium systems range from 50 to 1000 horsepower. Large systems can be considered above 1000 horsepower. Division of sizes into these groups is entirely arbitrary. Care must be taken to resist the temptation to over motor or under motor a belt flight to enhance standardization. An over motored drive results in poor efficiency and the potential for high torques, while an under motored drive could result in destructive overspending on regeneration, or overheating with shortened motor life (Lords, et al., 1978). Torque Control. Belt designers try to limit the starting torque to no more than 150% of the running torque (CEMA, 1979; Goodyear, 1982). The limit on the applied starting torque is often the limit of rating of the belt carcass, belt splice, pulley lagging, or shaft deflections. On larger belts and belts with optimized sized components, torque limits of 110% through 125% are common (Elberton, 1986). In addition to a torque limit, the belt starter may be required to limit torque increments that would stretch belting and cause traveling waves. An ideal starting control system would apply a pretension torque to the belt at rest up to the point of breakaway, or movement of the entire belt, then a torque equal to the movement requirements of the belt with load plus a constant torque to accelerate the inertia of the system components from rest to final running speed. This would minimize system transient forces and belt stretch (Shultz, 1992). Different drive systems exhibit varying ability to control the application of torques to the belt at rest and at different speeds. Also, the conveyor itself exhibits two extremes of loading. An empty belt normally presents the smallest required torque for breakaway and acceleration, while a fully loaded belt presents the highest required torque. A mining drive system must be capable of scaling the applied torque from a 2/1 ratio for a horizontal simple belt arrangement, to a 10/1 ranges for an inclined or complex belt profile. Each drive system will require a control system to regulate the starting mechanism. The most common type of control used on smaller to medium sized drives with simple profiles is termed "Open Loop Acceleration Control". In open loop, the control system is previously configured to sequence the starting mechanism in a prescribed manner, usually based on time. In open loop control, drive-operating parameters such as current, torque, or speed do not influence sequence operation. This method presumes that the control designer has adequately modeled drive system performance on the conveyor. For larger or more complex belts, "Closed Loop" or "Feedback" control may he utilized. In closed loop control, during starting, the control system monitors via sensors drive operating parameters such as current level of the motor, speed of the belt, or force on the belt, and modifies the starting sequence to control, limit, or optimize one or wore parameters. Closed loop control systems modify the starting applied force between an empty and fully loaded conveyor. The constants in the mathematical model related to the measured variable versus the system drive response are termed the tuning constants. These constants must be properly adjusted for successful application to each conveyor. The most common schemes for closed loop control of conveyor starts are tachometer feedback for speed control and load cell force or drive force feedback for torque control. On some complex systems, It is desirable to have the closed loop control system adjust itself for various encountered conveyor conditions. This is termed "Adaptive Control". These extremes can involve vast variations in loadings, temperature of the belting, location of the loading on the profile, or multiple drive options on the conveyor. There are three common adaptive methods. The first involves decisions made before the start, or 'Restart Conditioning'. If the control system could know that the belt is empty, it would reduce initial force and lengthen the application of acceleration force to full speed. If the belt is loaded, the control system would apply pretension forces under stall for less time and supply sufficient torque to adequately accelerate the belt in a timely manner. Since the belt only became loaded during previous running by loading the drive, the average drive current can be sampled when running and retained in a first-in-first-out buffer memory that reflects the belt conveyance time. Then at shutdown the FIFO average may be use4 to precondition some open loop and closed loop set points for the next start. The second method involves decisions that are based on drive observations that occur during initial starting or “Motion Proving". This usually involves a comparison In time of the drive current or force versus the belt speed. if the drive current or force required early in the sequence is low and motion is initiated, the belt must be unloaded. If the drive current or force required is high and motion is slow in starting, the conveyor must be loaded. This decision can be divided in zones and used to modify the middle and finish of the start sequence control. The third method involves a comparison of the belt speed versus time for this start against historical limits of belt acceleration, or 'Acceleration Envelope Monitoring'. At start, the belt speed is measured versus time. This is compared with two limiting belt speed curves that are retained in control system memory. The first curve profiles the empty belt when accelerated, and the second one the fully loaded belt. Thus, if the current speed versus time is lower than the loaded profile, it may indicate that the belt is overloaded, impeded, or drive malfunction. If the current speed versus time is higher than the empty profile, it may indicate a broken belt, coupling, or drive malfunction. In either case, the current start is aborted and an alarm issued. The best belt starting system is one that provides acceptable performance under all belt load Conditions at a reasonable cost with high reliability. No one starting system meets all needs. The belt designer must define the starting system attributes that are required for each belt. In general, the AC induction motor with full voltage starting is confined to small belts with simple profiles. The AC induction motor with reduced voltage SCR starting is the base case mining starter for underground belts from small to medium sizes. With recent improvements, the AC motor with fixed fill fluid couplings is the base case for medium to large conveyors with simple profiles. The Wound Rotor Induction Motor drive is the traditional choice for medium to large belts with repeated starting duty or complex profiles that require precise torque control. The DC motor drive, Variable Fill Hydrokinetic drive, and the Variable Mechanical Transmission drive compete for application on belts with extreme profiles or variable speed at running requirements. The choice is dependent on location environment, competitive price, operating energy losses, speed response, and user familiarity. AC Variable Frequency drive and Brush less DC applications are limited to small to medium sized belts that require precise speed control due to higher present costs and complexity. However, with continuing competitive and technical improvements, the use of synthesized waveform electronic drives will expand. 10