【正文】 ng it to the field of engineering systems design. A system design theory for largescale and plex system is not yet fully developed. Particularly, the question of how to simplify a plicated or plex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outes of formal representations in puter sciences and operations research, 安徽建筑大學 畢業(yè)設計（論文） 32 such as discrete event system modeling, can advance future development in engineering design. From a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely plex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a ponent design and a system design stage. At ponent design stage, single functions are designed and verified. At system design stage, ponents are aggregated and the whole system behavior and functionality is tested through simulation. In general, a plete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design. SIEMENS PLC SIMATIC S7300 series PLC applied to all walks of life and various occasions in the detection, monitoring and control of automation, its power to both the independent operation of, or connected to a work able to achieve plex control. The photoelectric products with isolation, high electromagic patibility。s own Communications protocol (of the agreement ASCII), the baud rate to M bit / s (adjustable). So that can greatly increase the scope of munications so that the control system configuration more flexible and convenient. Of any kind with a serial interface peripherals, such as: printers or bar code readers, Drives, a modem (Modem), the top PCconnected, and so can be used. Users can program to develop munication protocols, the exchange of data (for example: ASCII character code), RS232 interfaces with the equipment can also be used PC / PPI cable linking the free munication munications. 安徽建筑大學 畢業(yè)設計（論文） 33 When the PC offline, under the control of the next crew, the whole system can operate normally. PC that is by control centre, mainly by the PC and laser printer po nents, using SIMATIC WINCC software platform, the allChinese interface, friendly manmachine dialogue. Managers and operators can be observed through a PC, shown in the various kinds of information to understand the present and past the icestorage operation of the automatic control system and all the parameters, and through the mouse to print equipment management and implementation tasks. WINCC software in the field of automation can be used for all the operators’ control and monitoring tasks. Can be controlled in the process of the events clearly show, and shows the current status and order records, the recorded data can show all or select summary form, or may be required for editing, printing and output statements and trends . WINCC able to control the critical situation in the early stages of the report, and the signal can be displayed on the screen, can also use sound to be felt. It supported by online help and operational guidelines to eliminate failure. WINCC a workstation can be devoted to the process control to the process so that important information not is shielded. Softwareassisted operation strategy ensures that the pro。 has strong antijamming and antivibration and impact resistance, so in a harsh working environment has been widely Applications. I also mean freedom of munication S7300 type PLC39。 IEC 61499, 1998。 由于工業(yè) PLC 無論何時不可能廣泛的涉及到 MAP，生產廠家正在考慮專用網絡。例如，雖然當新的生產自動化協(xié)議 版本使用之時以 版本為基礎的產品將會被汰，但是現(xiàn)在人們仍然將產品用于 版。 通信 通信對于個人自動單元是很重要的。某一 WINCC 工作站可專門用于過程控制以使那些重要的過程信息不被屏蔽。 WINCC 軟件在自動化領域中可用于所有的操作員控制和監(jiān)控任務。用戶可通過編程來編制通訊協(xié)議、交換數(shù)據(jù)（例如： ASCII 碼字符），具有 RS232 接口的設備也可用 PC/PPI 電纜連接起來進行自由通訊方式通訊。 自由通訊口方式也是 S7300 型 PLC 的一個很有特色的功能，它使 S7300型 PLC 可以與任何通訊協(xié)議公開的其它設備、控制器進行通訊，即 S7 300 型PLC 可以由用戶自己定義通訊協(xié)議（例 ASCII 協(xié)議），波特率為 1。一般來說，所有部分都完全的驗證是不可能的?，F(xiàn)代超大規(guī)模集成電路設計（ Very Large Scale IntegrationVLSI）是及其復雜的， 一個集成電路一般有幾百萬個晶體管，而且產品開發(fā)周期大都三年左右。針對大規(guī)模和復雜系統(tǒng)的系統(tǒng)設計理安徽建筑大學 畢業(yè)設計（論文） 29 論并沒有成熟。因此，軟件的使用周期花費是總共花費的一個固定不變的增長部分。其結果是，一方面造成了大量而低效率的程序代碼，另一方面并沒有獲得高的硬件性能。 系統(tǒng)的方法通過使用原有的軟件模塊，有助于增加設計自動化的水平，同時也將提供一種可管理的大規(guī)模系統(tǒng)設計的方法。在發(fā)展和傳播“ＳＴＡＴＥ－ＯＦ－ＴＨＥ－ＡＲＴ”已經形成標準 [IEC 60848, 1999。 研究表明，在自動化系統(tǒng)中，程序實現(xiàn)的方法已經與計算機資源應用的急速增長不能匹配。 安徽建筑大學 畢業(yè)設計（論文） 21 安徽建筑大學 畢業(yè)設計（論文） 22 子程序，將輸入的溫度值進行轉化 安徽建筑大學 畢業(yè)設計（論文） 23 致 謝 本課題的研究是在我的導師李老師的悉心指導下完成的，趙老師學識 淵博、治學態(tài)度嚴謹、工作一絲不茍 ，更有誨人不倦的師者風范， 在此謹向 趙 老師致以誠摯的謝意和崇高的敬意 ！ 此外，衷心感謝本組的其他成員，若是沒有他們，也就不會有這篇論文的產生。 設定： 水箱內溫度 ＶＤ４００ 入口電磁閥 Ｑ０ .０ 出口電磁閥 Ｑ０ .１ 啟動變頻 器 Ｑ０ .２ 報警器 Ｑ０ .３ 控制加熱量大小 ＡＱＷ０ 設定溫度 ＶＤ４０４ 溫度輸入 ＡＩＷ０ 安徽建筑大學 畢業(yè)設計（論文） 18 程序的編寫 主程序，初始化并且啟動電磁閥 將采集到的水箱內的溫度和設定的溫度進行對比，要是大于這個溫度值，報警器就動作． 安徽建筑大學 畢業(yè)設計（論文） 19 主程序，將采集到的溫度通過程序運算抓換得出真實的溫度值?？煽毓杵骷c 雙極型晶體管 有密切的關系，二者的傳導 過程 皆牽涉到電子和 空穴 ，但可控硅的開關機制和 雙極晶體管 是不同的，且因為器件結構不同，可控硅器件有較寬廣范圍的電流、電壓控制能力。 可控硅又稱晶閘管（ Silicon Controlled Rectifier,SCR）。 安徽建筑大學 畢業(yè)設計（論文） 16 可控硅 可控硅，是可控硅 整流 元件的簡稱，是一種具有三個 PN 結的四層結構的大功率半導體 器件 ，亦稱為晶閘管。 單極性的 歸一化的公式 ： )3202