【正文】 ough a puter (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a puter if you have the software needed for programming. Today’s transmission puters are ideal for reprogramming a PLC controller in factory itself. This is of great importance to industry. Once the system is corrected, it is also important to read the right program into a PLC again. It is also good to check from time to time whether program in a PLC has not changed. This helps to avoid hazardous situations in factory rooms (some automakers have established munication networks which regularly check programs in PLC controllers to ensure execution only of good programs).Almost every program for programming a PLC controller possesses various useful options such as： forced switching on and off of the system input/outputs (I/O lines), program follow up in real time as well as documenting a diagram. This documenting is necessary to understand and define failures and malfunctions. Programmer can add remarks, names of input or output devices, and ments that can be useful when finding errors, or with system maintenance. Adding ments and remarks enables any technician (and not just a person who developed the system) to understand a ladder diagram right away. Comments and remarks can even quote precisely part numbers if replacements would be needed. This would speed up a repair of any problems that e up due to bad parts. The old way was such that a person who developed a system had protection on the program, so nobody aside from this person could understand how it was done. Correctly documented ladder diagram allows any technician to understand thoroughly how system functions. Electrical supply is used in bringing electrical energy to central processing unit. Most PLC controllers work either at 24 VDC or 220 VAC. On some PLC controllers you’ll find electrical supply as a separate module. Those are usually bigger PLC controllers, while small and medium series already contain the supply module. User has to determine how much current to take from I/O module to ensure that electrical supply provides appropriate amount of current. Different types of modules use different amounts of electrical current.This electrical supply is usually not used to start external input or output. User has to provide separate supplies in starting PLC controller inputs because then you can ensure so called “pure” supply for the PLC controller. With pure supply we mean supply where industrial environment can not affect it damagingly. Some of the smaller PLC controllers supply their inputs with voltage from a small supply source already incorporated into a PLC.Four、PLC design criteria A systematic approach to designing PLC software can overe deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a highlevel description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, welldefined control systems design outes are conducive to automatic code generation An ability to produce control software executable on mercial distinct logic controllers can reduce programming leadtime and labor cost. In particular, the thesis is relevant with respect to the following aspects.In modern manufacturing, systems are characterized by product and process innovation, bee customerdriven and thus have to respond quickly to changing system requirements. A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused in realtime, therefore, giving a significant petitive edge in industrial practice.Studies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of puting resources. For instance, the programming of PLCs still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debuggi。Third, adaptability good。綜上所述，本文對凹版印刷機(jī)的PLC控制系統(tǒng)的設(shè)計采用PLC控制變頻器調(diào)速的基本方法，綜合的運(yùn)用了閉環(huán)控制，反饋調(diào)節(jié)的基本原理，在原有的基礎(chǔ)上實現(xiàn)加入加速裝置的新創(chuàng)意，提高了系統(tǒng)的穩(wěn)定性和效率，在今后的工作中將會繼續(xù)研究這方面的問題。2． 提出了一種采用張力傳感器的力電轉(zhuǎn)換裝置使比較抽象的張力檢測轉(zhuǎn)變成我們能夠?qū)崟r檢測的電信號。7．設(shè)定加速上限和減速下限：當(dāng)系統(tǒng)計數(shù)次數(shù)大于等于500次時，M0通道被接通，則常閉觸點(M0)此時動作為關(guān)閉，完成對加速過程斷電，此時加速結(jié)束。3．啟動整個系統(tǒng)：此時系統(tǒng)按下啟動按鈕，即此時(X000)被接通，M2由于上條語句構(gòu)成自鎖，(Y001)為系統(tǒng)指示燈，當(dāng)系統(tǒng)啟動按鈕被按下此時系統(tǒng)指示燈被點亮，并且構(gòu)成自鎖，此時系統(tǒng)主變頻運(yùn)行(Y004)、后變頻運(yùn)行(Y005)、前變頻運(yùn)行(Y006)基于通道M2的指示而接通或者斷開。比例I/微分D=2，具體值可根據(jù)儀表定，再調(diào)整比例帶P，P過頭，到達(dá)穩(wěn)定的時間長，P太短，會震蕩，永遠(yuǎn)也打不到設(shè)定要求[6]?，F(xiàn)在一般采用的是臨界比例法。二是工程整定方法，它主要依賴工程經(jīng)驗，直接在控制系統(tǒng)的試驗中進(jìn)行，且方法簡單、易于掌握，在工程實際中被廣泛采用。它是根據(jù)被控過程的特性確定PID控制器的比例系數(shù)、積分時間和微分時間的大小。解決的辦法是使抑制誤差的作用的變化“超前”，即在誤差接近零時，抑制誤差的作用就應(yīng)該是零。 微分(D)控制：在微分控制中，控制器的輸出與輸入誤差信號的微分(即誤差的變化率)成正比關(guān)系。這樣，即便誤差很小，積分項也會隨著時間的增加而加大，它推動控制器的輸出增大使穩(wěn)態(tài)誤差進(jìn)一步減小，直到等于零。：在積分控制中，控制器的輸出與輸入誤差信號的積分成正比關(guān)系。其控制器的輸出與輸入誤差信號成比例關(guān)系。Bit2：輸出變化量(增方)超出。2．PID控制說明表41微分時間常數(shù)TD增大時，超調(diào)量減小，動態(tài)性能得到改善，但是抑制高頻干擾的能力下降。因此，積分部分可以消除穩(wěn)態(tài)誤差，提高控制精度，但是積分作用的動作緩慢，可能給系統(tǒng)的動態(tài)穩(wěn)定性帶來不良影響。在整定參數(shù)時應(yīng)把握住PID參數(shù)與系統(tǒng)動態(tài)、靜態(tài)性能之間的關(guān)系。如果使用有斷電保持功能的數(shù)據(jù)寄存器，不需要重復(fù)寫入。［S1］和［S2］分別用來存放給定值SV和當(dāng)前測量到的反饋值PV，［S3］~[S3]＋6用來存放控制參數(shù)的值，運(yùn)算結(jié)果MV存放在［D］中。當(dāng)線速度達(dá)到1015米/分鐘的時候，才對主牽引停止加速，當(dāng)人工調(diào)節(jié)印刷套準(zhǔn)之后達(dá)到套準(zhǔn)要求，再次按下加速按鈕繼續(xù)加速運(yùn)行。圖41 GX DEVELOPER 系統(tǒng)總流程圖系統(tǒng)的控制流程為：在整個系統(tǒng)開始工作之前先按下警鈴按鈕，此時是為了避免出現(xiàn)不必要的意外事故。圖36 主牽引變頻器端子接線圖第4章 系統(tǒng)軟件設(shè)計GX DEVELOPER是三菱PLC的編程軟件。圖34 PLC外部I/O接線圖MD320系列變頻器有豐富的擴(kuò)展卡選配件，包括I/O擴(kuò)展卡、Modbus卡、RTU總線卡、供水?dāng)U展卡等?？刂茖ο螅核俣瓤刂婆c轉(zhuǎn)矩控制兩種?？刂埔?guī)模：16~256點內(nèi)置8K容量的EEPROM存儲器,最大可以擴(kuò)展到16K，~。