外文翻譯--礦井提升機精確測速的微機實現(xiàn)【中英文文獻譯文】
外文翻譯-礦井提升機精確測速的微機實現(xiàn)【中英文文獻譯文】,中英文文獻譯文,外文,翻譯,礦井,提升,晉升,精確,測速,微機,實現(xiàn),中英文,文獻,譯文
中文譯文礦井提升機精確測速的微機實現(xiàn)礦井提升機是礦井生產(chǎn)的重要設(shè)備,擔負礦物、材料、設(shè)備和人員在井筒內(nèi)往復運輸?shù)娜蝿?,在礦井的正常生產(chǎn)中占有極其重要地位。為保證提升設(shè)備安全可靠地運行,要求控制系統(tǒng)的性能良好,要有較高的調(diào)速性能和位置控制。隨著計算機應用科學的飛速發(fā)展,采用計算機控制系統(tǒng)取代原來的電控系統(tǒng)是一種趨勢。由于礦井提升機控制系統(tǒng)高度復雜性和對安全可靠性的嚴格要求,目前國內(nèi)還未開發(fā)出較為理想、適于工業(yè)現(xiàn)場要求的計算機控制系統(tǒng)。本文介紹了作者從事這方面工作的一個片斷。1 對微機測速裝置的要求對微機測速裝置的一般要求是:分辨能力強、精度高,盡可能短的檢測時間。1.1分辨率用微機進行轉(zhuǎn)速檢測時,分辨率用改變一個測量計數(shù)字所對應的被測轉(zhuǎn)速的變化量來表示。設(shè)轉(zhuǎn)速由n1變?yōu)閚2時,引起測量計數(shù)值改變了一個字,用Q代表分辨率: r/min (1)分辨率的大小與系統(tǒng)的控制精度關(guān)系甚大,Q值愈小,分辨能力愈強,系統(tǒng)的控制精度愈高,它是測速裝置的一個重要指標。1. 2測速精度測速精度是指測速裝置對實際轉(zhuǎn)速測量的精確程度。如果用n代表測量值與實際值之差,n代表實際轉(zhuǎn)速,代表用相對值表示的測量誤差,則(2)顯然,%愈小,測速精度愈高,系統(tǒng)的控制精度也將愈高。測量誤差%的大小決定于測速元件的制造精度,并與測速方法有關(guān)。1. 3檢測時間檢測時間是指兩次轉(zhuǎn)速采樣之間的時間間隔。檢測時間的長短對系統(tǒng)的控制性能影響很大,如果檢測時間很長,則系統(tǒng)將難以實現(xiàn)穩(wěn)定的快速響應。檢測時間愈短,對于系統(tǒng)的控制性能的改善愈有利。2微機測速的一般方法由光電式旋轉(zhuǎn)編碼器與提升機的軸硬性聯(lián)接,提升機每轉(zhuǎn)發(fā)出一定數(shù)量(1080個)的脈沖信號,由計數(shù)器記下脈沖數(shù),并送給計算機處理以實現(xiàn)微機測速。常用的測速方法主要有以下兩種。2.1 M法測速M法測速是在相等的時間間隔內(nèi)讀取旋轉(zhuǎn)編碼器發(fā)出的脈沖個數(shù)以算出轉(zhuǎn)速。在相同的時間內(nèi)旋轉(zhuǎn)編碼器發(fā)出的脈沖數(shù)不同,測量值也不相同。M法測速的原理圖如圖1所示。由計數(shù)器對旋轉(zhuǎn)編碼器發(fā)送的脈沖計數(shù),定時器每隔時間T向CPU發(fā)出一次中斷請求,根據(jù)計數(shù)值的大小求出對應的轉(zhuǎn)速。旋轉(zhuǎn)編碼器每轉(zhuǎn)發(fā)出脈沖1080個,在T時間內(nèi)共發(fā)生m個脈沖,則轉(zhuǎn)速為: r/min (3)這種測速方法是由計數(shù)值m的大小反映轉(zhuǎn)速的高低,因而稱為M法測速。(1)分辨率根據(jù)分辨率的定義由式(3)可得:(4)可見,M法測速時的分辨率與速度的大小無關(guān),和轉(zhuǎn)速采樣周期T有關(guān)。(2)測速精度利用旋轉(zhuǎn)編碼器測速時,其測量誤差決定于編碼器的制造精度并與轉(zhuǎn)速的大小有關(guān)。設(shè)旋轉(zhuǎn)編碼器兩相鄰脈沖之間的角偏差為。一個檢測周期的計數(shù)值為m,則測量誤差為:(5)轉(zhuǎn)速愈低,m愈小,測量誤差愈大,測速精度愈低。隨著轉(zhuǎn)速下降測速精度降低是M法測速的一個缺點。(3)檢測時間:就等于測量周期T。2. 2T法測速T法測速是測出旋轉(zhuǎn)編碼器兩個輸出脈沖之間的間隔時間來計算轉(zhuǎn)速的測速方法。時間的測量由一個計數(shù)器對已知頻率的時鐘脈沖進行計數(shù)求得,T法測速原理圖如圖2所示。旋轉(zhuǎn)編碼器每輸出一個脈沖都通過微機接口向CPU發(fā)出一次中斷,CPU響應后從計數(shù)器中讀出計數(shù)值,由計數(shù)值即可算出轉(zhuǎn)速。設(shè)時鐘頻率為f,兩個脈沖間的計數(shù)值為m,則轉(zhuǎn)速n為: r/min (6)可以看出,T法測速與M法恰恰相反.轉(zhuǎn)速愈高測量計數(shù)值m愈小。(1)分辨率設(shè)轉(zhuǎn)速的計數(shù)值由m變?yōu)閙-1,根據(jù)分辨率的定義:(7)由式(7)得,Q值的大小與轉(zhuǎn)速有關(guān),轉(zhuǎn)速愈小,m愈大,Q則愈小,測速裝置的分辨能力愈強。T法測速的優(yōu)點在于低速段對轉(zhuǎn)速有較強的分辨能力,從而可提高低速的控制性能。(2)測速精度測量誤差就等于旋轉(zhuǎn)編碼器兩脈沖間的角偏差,即測量誤差:(8)它只決定于編碼器的制造精度,與被測轉(zhuǎn)速無關(guān),它比M法測速精度要差。(3)檢測時間:由于旋轉(zhuǎn)編碼器每轉(zhuǎn)發(fā)出1080個脈沖,所以兩脈沖之間的間隔時間為: s (9)式(9)表明,T法測速檢測時間隨轉(zhuǎn)速而變。3 礦井提升機對轉(zhuǎn)速測量的要求礦井提升機的運行過程,是一個周期性的過程。一般提升機的提升周期包括加速、等速、減速、爬行、停車五個階段。在五個階段中,提升機的運行速度是有很大差別的。下面給出安徽省某礦提升機運行的速度圖,見圖3。由速度圖可以看出,在加速段和減速段提升機的速度是一個按一定加速度或減速度不斷變化的過程,等速段以較高運行速度運行,爬行段的速度相對來講要慢得多,只有0.4m/s,總體來說,提升機運行過程是一個速度在較大范圍內(nèi)不斷變化的過程,要想實現(xiàn)微機的準確測速,則測速方法必須滿足在較高速度和較低速度段均能準確測量的要求。為保障提升機運行的高安全性,在提升機的各種保護中,有等速段過速保護和減速段過速保護,等速段運行速度如超過最高轉(zhuǎn)速Vm的15%,提升機將安全制動;減速段運行中,如測出速度超過給定值10%,亦將實施安全制動。因而,為了準確反映提升機運行中的速度狀況,實現(xiàn)控制系統(tǒng)安全、可靠、連續(xù)地運行,要求微機測出的速度必須準確,能夠滿足一定的精度。4 提升機精確測速的M/T法由上述可知,提升機的速度測量要求有較高的精確度,能夠準確地反映提升機運行中的實際轉(zhuǎn)速。前述的M法測速,低速段測速精度比較低;T法測速,低速段轉(zhuǎn)速分辨能力較強,但其測速精度比M法又差得多,它們用于提升機測速均不夠理想;而M/T測速法則綜合兩種方法的優(yōu)點,既可以低速段可靠地測速,又在高速段具有較高的分辨能力,適應了提升機對速度測量的要求。M /T法則測速原理見圖4。其中T0由一定時器定時,檢測周期T由T0結(jié)束后,脈沖發(fā)生器輸出的第一個脈沖決定,即T=T0+T, m1為T時間內(nèi)編碼器發(fā)出的脈沖數(shù),m2為周期T內(nèi)對時鐘脈沖的計數(shù)值。轉(zhuǎn)速的表達式為:r/min (10)式中:f一時鐘脈沖的頻率;1080一編碼器每轉(zhuǎn)發(fā)出的脈沖數(shù)。我們開發(fā)的IPC控制系統(tǒng)中,M /T法測速是依賴于HY-6220計數(shù)/定時器模板實現(xiàn)的,這是IBM PC XT/AT總線兼容的隔離型可編程多功能模板,板上有8253,8255,8259三種可編程器件。M/T法測速的硬件實現(xiàn)圖見圖5。工作過程如下:計算機發(fā)出啟動信號,從編碼器輸出第一個脈沖起,8253定時器(T0)計數(shù)開始,與此同時8253計數(shù)器(m2)亦開始計數(shù),20ms后T0定時器向8259發(fā)中斷信號,直到編碼器再送來一個脈沖,停止m1和m2計數(shù)器,并通過8259向CPU發(fā)出中斷請求,計算轉(zhuǎn)速n。HY-6220模板軟件編程框圖見圖6。以上給出M/T法測速的硬件實現(xiàn)圖和軟件框圖,現(xiàn)討論M /T法測速的分辨率等問題。(1)分辨率:M/T法測速計數(shù)值m1及m2都隨轉(zhuǎn)速而變化。在此分別對高速段和低速段討論分辨率。在高速段,T0T,即TT0,認為M2不隨轉(zhuǎn)速變化。該種情況下可得: r/min把M2= fTfT0代入上式得:Q=60/1080T0。這與M法測速分辨完全相同。在轉(zhuǎn)速很低時,m1=l。m2隨轉(zhuǎn)速變化而變化,其分辨率為: r/min這與T法測速完全相同。圖6 HY-6220模板軟件編程框圖由上分析,M/T法測速在高速段與M法相近,在低速段則與T法相近,兼有二者的優(yōu)點,在高速和低速均有較強的分辨能力。(1)測速精度:高速段(M11),測速精度與M法相同,即%=p %/m1;在低速段(m11)與M法相近,轉(zhuǎn)速愈高,檢測時間愈接近T0,在低速段(m1l)則與T法接近。5結(jié)論M/T法測速的微機實現(xiàn),滿足了提升機運行對速度測量的要求,在等速段、減速段和爬行段均能滿足一定的精度要求,保證了提升機安全、可靠、持續(xù)地運行。The mine pit elevator measured precisely the fast microcomputer realizesThe mine pit elevator is the mine pit production important equipment, the load mineral, the material, the equipment and the personnel moves back and forth transportations duty in the well chamber, holds the extremely important position in the mine pit regular production. Moves reliably safely for the guarantee lift technique, the request control systems performance is good, must have the high velocity modulation performance and the position control.Along with the computer applied sciences swift development, uses the computer control system substitution original electrically controlled system is one tendency. As a result of the mine pit elevator control system highly complexity and to the security reliable strict request, domestic has not developed at present is more ideal, is suitable for the industry scene request the computer control system. This article introduced the author is engaged in a piece which this aspect works.1 To the microcomputer measured that the fast installment request To the microcomputer measured the fast installment the general request is: Resolution is strong, the precision is high, as far as possible short examination time. 1.1 resolution When carries on the rotational speed examination with the microcomputer, the resolution with changes was measured that the rotational speed which a survey meter digit corresponds the change quantity expressed. Supposes the rotational speed when become n2 by n1 causes the survey meter value to change a character, represents the resolution with Q:The resolution size and systems control precision relations are really big, the Q value is smaller, resolution is stronger, systems control precision is higher, it is measures the fast installment an important target.1.2 measured that fast precision Measured the fast precision is refers to measures the fast installment to the actual tachometric survey precise degree. If with n represents the observed value and the actual value difference, n represents the actual rotational speed, % represent the measuring error which expressed with the relative value, thenObviously, % is smaller, measured that the fast precision is higher; systems control precision will be also higher. The measuring error % sizes decided that in measured the fast parts manufacture precision, and with measured the fast method concerns.1.3 examination time The examination time is refers to between two time rotational speed sampling the time-gap. The examination times length the control performance influence is very big to the system, if the examination time is very long, then the system will realize the stable fast response with difficulty. The examination time is shorter, is more advantageous regarding systems control performances improvement.2 The microcomputer measured that fast general method By the electro-optical type revolving encoder and elevators axis solid joint, the elevator retransmits the certain amount every time (1080) the signal impulse, takes down the pulse number by the counter, and gives computer processing to realize the microcomputer to measure fast. Commonly used measured that the fast method mainly has the following two kinds.2.1 The M law measures fastThe M law measured that fast is reads the pulse integer which in the equal time-gap the revolving encoder sends out to figure out the rotational speed. The pulse number which sends out in the same time internal rotation encoder is different; the observed value is not same. The M law measured that fast schematic diagram as shown in Figure 1.By the counter the pulse counting which transmits to the revolving encoder, timer every other time T sends out an interrupt request to CPU, extracts corresponding according to the counting values size the rotational speed. The revolving encoder retransmits pulse 1080 every time, altogether has m pulse in the T time, then the rotational speed is:This kind measured that the fast method is by the counting value m size reflection rotational speed height, thus is called the M law to measure fast.(1) ResolutionMay result in according to the resolution definition by type (3):Obviously, the M law measured fast when the resolution has nothing to do with the speed size, concerns with rotational speed sampling period T.(2) measured that fast precision When measures using the revolving encoder fast, its measuring error decided that concerns in encoders manufacture precision and with the rotational speed size. Supposes between the revolving encoder two neighboring pulses the angular deviations are. p%, an examination cycles counting value is m, then the measuring error is:The rotational speed is lower, m is smaller, the measuring error is bigger, measured that the fast precision is lower. Along with the RPM drop measured that the fast precision reduces is the M law measures a fast shortcoming.(3) Examines the time: Is equal to survey cycle T.2. 2 T law measured that fast T law measured fast is determines between the revolving encoder two output pulses the time interval to calculate the rotational speed to measure the fast method. The time survey carries on the counting by a counter to the known frequencys clock pulse to obtain, the T law measured that fast schematic diagram as shown in Figure 2.The revolving encoder outputs a pulse through the microcomputer connection sends out an interrupt to CPU, after the CPU response, to read out the counting value every time from the counter, then figures out the rotational speed by the counting value. Supposes the clock rate is f, counting values between two pulses are m, then rotational speed n is:May see, the T law measured that fast is just the opposite with the M law. Rotational speed higher survey meter value m is smaller.(1) ResolutionSupposes, because the rotational speed counting value becomes m-1 by m, according to resolution definition:By type (7), Q value size and rotational speed related, the rotational speed is smaller, m is bigger, Q is smaller, measured that the fast installment resolution is stronger. The T law measured that the fast merit lies in the low speed section to have the strong resolution to the rotational speed, thus may enhance the low speed the control performance.(2) Measures the fast precisionMeasuring error is equal to the angular deviations between the revolving encoder two pulses p %, namely measuring error:It only decided that in encoders manufacture precision, with is measured the rotational speed to have nothing to do with, it compared to the M law measured that the fast precision must miss.(3) examines the time: Because the revolving encoder retransmits 1080 pulses every time, therefore between two pulses time intervals are:Type (9) indicated that the T law measured the fast examination time changes along with the rotational speed.3 Mine pit elevator to tachometric surveys request The mine pit elevators movement process is a periodic process. Generally elevators promotion cycle including the acceleration, the constant speed, the deceleration, crawling, stops five stages. In five stages, elevators running rate has the very wide difference. Below gives the AnhuiProvince some ore elevator movement the speed chart, see Figure 3. May see by the speed chart, in the acceleration leg and the deceleration section elevators speed is one process which changes unceasingly according to certain acceleration or the retarded velocity, constant speed Duan Yijiao the high running rate movement, the crawling section speed relative says must be much slower, only then 0.4m/s, generally speaking, the elevator movement process is a speed the process which changes unceasingly in the wide range, if wants to realize the microcomputer to measure accurately fast, then measured that the fast method must satisfy in the high speed and compares the low speed section to be able the correct measurement request.In order to safeguard the elevator movement the high security, in elevators each kind of protection, has the constant speed section too fast protection and the deceleration section too fast protection, the constant speed section running rate like surpasses highest rotational speed Vm 15%, elevator safety arrestment; In deceleration section movement, if determines the speed to surpass given value 10%, also will implement the safety arrestment. Therefore, to reflect in the elevator movement accurately the speed condition, realizes the control system security, reliably, to move continuously, requests the speed which the microcomputer determines to be accurate, can satisfy certain precision.4 The elevator measured precisely fast M/T law By above may know, elevators velocity measurement request has the high precision, can reflect in the elevator movement accurately the actual rotational speed. The fore-mentioned M law measures fast, low speed Duan Cesu the precision is quite low; The T law measures fast, low speed section rotational speed resolution is strong, but it measured that the fast precision is also much worse than the M law, they use in the elevator measuring the fast insufficient ideal; But M/T measured that the fast principle synthesizes two methods the merits, both may the low speed section reliable surveying fast, and also has the high resolution in the high speed section, adapted the elevator to the velocity measurement request. The M /T principle measured that the fast principle sees Figure 4.And T0 by a timer fixed time, examination cycle T had finished after T0, the pulse generator outputs first pulse decided that namely T=T0+T, m1 is the pulse number which in the T time the encoder sends out, m2 is in cyclical T to the clock pulse counting value. The rotational speed expression is:A in the formula f clock pulse frequency; the 1080yi encoder retransmits every time pulse number.We develop in the IPC control system, the M /T law measured that fast is relies on the HY-6220 counting/timer template realizes, this is IBM PC the XT/AT main line compatible isolation type programmable multi-purpose template, on the board has 8253,8255,8259 three kind of programmable components. The M/T law measured that the fast hardware realizes the chart to see Figure 5.The work process is as follows: The computer sends out the start signal, outputs the first pulse from the encoder, 8253 timer (T0) counting start, 8253 counters (m2) also starts to count at the same time, after 20ms, the T0 timer to 8259 round of signals of stop, sends a pulse again until the encoder, stops m1 and the m2 counter, and through 8259 sends out the interrupt request to CPU, computation rotational speed n.The HY-6220 template software programming diagram see Figure 6.above Gives the M/T law to measure that the fast hardware realizes the chart and the software diagram, presently discusses the M /T law to measure questions and so on fast resolution.(1) Resolution:M/T law velocity meter value m1 and m2 change along with the rotational speed. In this separately to high speed section and low speed section discussion resolution. In the high speed section, T0T, namely TT0, thinks M2 not along with the rotational speed change. In this kind of situation may result in:The M2= fTfT0 substitution above equation: Q=60/1080T0. This with the M law measured that the fast resolution is completely same. When the rotational speed is very low, m1=l, m2 changes along with the rotational speed change, its resolution is:This measures with the T law fast identical.Figure 6 HY-6220 template software programming diagram analyzes by on, the M/T law measured that fast the law is close in high speed Duan Yum, is close in low speed Duan Ze and the T law, has at the same time the twos merit, has the strong resolution in high speed and the low speed.(2) Measures the fast precision:The high speed section (M11), measured that the fast precision and the M law are the same, namely %=p %/m1; in low speed section (m1(3) Examination time:The M/T law measured that fast examination cycle T under the different rotational speed is different, (m11) and the M law is close in the high speed section, the rotational speed is higher, examination time closer T0, in low speed section is close with the T law.5 conclusions The M/T law measured that the fast microcomputer realized, has satisfied the elevator movement to the velocity measurement request, in the constant speed section, the deceleration section and crawled Duan Junneng to satisfy certain accuracy requirement, had guaranteed the elevator safe, reliable, moved continually.
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