GE 350-027750-746001 K卡件,350-027750-746001 K燃機模塊
在DCS控制系統中,電源占有極重要的地位。電網干擾串入DCS控制系統主要通過DCS系統的供電電源(如CPU電源、I/O電源等)、變送器供電電源和與DCS系統具有直接電氣連接的儀表供電電源等耦合進入的?,F在,對于DCS系統供電的電源,350-027750-746001 K卡件一般都采用隔離性能較好電源,而對于變送器供電的電源和DCS系統有直接電氣連接的儀表的供電電源,并沒受到足夠的重視,雖然采取了一定的隔離措施,但普遍還不夠,主要是使用的隔離變壓器分布參數大,抑制干擾能力差,經電源耦合而串入共模干擾、差模干擾。
所以,對于變送器和共用信號儀表供電應選擇分布電容孝抑制帶大(如采用多次隔離和屏蔽及漏感技術)的配電器,以減少DCS系統的干擾。
此外,位保證電網饋點不中斷,可采用在線式不間斷供電電源(UPS)供電,提高供電的安全可靠性。并且UPS還具有較強的干擾隔離性能,是一種DCS控制系統的理想電源。
2 電纜選擇的敖設
為了減少動力電纜輻射電磁干擾,尤其是變頻裝置饋電電纜。筆者在某工程中,采用了銅帶鎧裝屏蔽電力電纜,從而降低了動力線生產的電磁干擾,該工程投產后取得了滿意的效果。
不同類型的信號分別由不同電纜傳輸,信號電纜應按傳輸信號種類分層敖設,嚴禁用同一電纜的不同導線同時傳送動力電源和信號,避免信號線與動力電纜靠近平行敖設,以減少電磁干擾。350-027750-746001 K燃機模塊
3 硬件濾波及軟件抗干擾措施
信號在接入計算機前,在信號線與地間并接電容,以減少共模干擾;在信號兩極間加裝濾波器可減少差模干擾。
由于電磁干擾的復雜性,要根本消除迎接干擾影響是不可能的,因此在DCS控制系統的軟件設計和組態時,還應在軟件方面進行抗干擾處理,進一步提高系統的可靠性。
from factory machine layout to unit operation in processing workshop; ⑤ The established network protocol and program language standards are adopted to ensure the network data exchange of users, such as TCP / IP, opc.xml and SQL query language.
Compared with traditional control technology, PAC technology mainly has the following advantages:
1) A single controller is adopted. PAC has a single controller, which can be used to process digital and analog I / O. it has motion vision function and modular instrument. Therefore, when users need vision and other functions, they do not have to buy other controllers.
2) Advanced control. Advanced control technologies such as fuzzy logic and neural network not only need powerful floating-point processor, but also need to occupy a lot of memory. PAC platform can meet these conditions.
3) Real time analysis. PAC can collect data from analog or digital I / O channels in real time and analyze these data in