描述
電氣系統(tǒng)控制的特點
電氣系統(tǒng)與熱工自動化相比在控制要求及運行過程中有著很多不同點,電氣的主要特點表現(xiàn)為:
(1)電氣設(shè)備相對熱工設(shè)備而言控制對象少,操作頻率低,有的系統(tǒng)或設(shè)備運行正常時,時常幾個月或更長時間才操作一次。
(2)電氣設(shè)備保護(hù)自動裝置要求可靠性高,動作速度快。發(fā)變組保護(hù)動作速度要求在40ms以內(nèi);自動準(zhǔn)同期采用同步電壓方式,轉(zhuǎn)速、電壓調(diào)整和滑壓控制要求在5ms以內(nèi);電壓自動調(diào)整裝置快速勵磁要求時間極短;廠用電快切裝置快速切換時間一般小于60~80ms,同步鑒定相位差5°~20°。
(3)300MW及以上機組一般每2臺機組共用1臺起/備變,任一機組檢修都不能影響另1臺機組的正常運行,因此DCS控制應(yīng)考慮其控制方式,確保只能有1臺機組的DCS實現(xiàn)對共用部分的控制,同時另一機組DCS能夠?qū)崿F(xiàn)實時監(jiān)視,并且這種操作控制權(quán)能實現(xiàn)切換。
(4)電氣設(shè)備電氣系統(tǒng)的聯(lián)鎖邏輯較簡單,但電氣設(shè)備本身操作機構(gòu)復(fù)雜。
因此,機組的電氣系統(tǒng)納入DCS控制,要求控制系統(tǒng)具有很高的可靠性。除了能實現(xiàn)正常起停和運行操作外,尤其要求能夠?qū)崿F(xiàn)實時顯示異常運行和事故狀態(tài)下的各種數(shù)據(jù)和狀態(tài),并提供相應(yīng)的操作指導(dǎo)和應(yīng)急處理措施,保證電氣系統(tǒng)自動控制在最安全合理的工況下工作。
2 電氣系統(tǒng)納入DCS監(jiān)控的范圍
根據(jù)單元機組的運行和電氣控制的特點,在工程的應(yīng)用中采用將發(fā)電機—變壓器組和廠用電源等電氣系統(tǒng)的控制都納入DCS監(jiān)控。
從升壓站(不包括升壓站)至電廠側(cè)的所有主廠房內(nèi)電氣系統(tǒng)均納入DCS監(jiān)控,主要系統(tǒng)歸納為:
發(fā)變組系統(tǒng)(不包括變壓器本身的通風(fēng)系統(tǒng));
發(fā)電機勵磁系統(tǒng);
高壓廠用電源系統(tǒng)(包括廠用電源正常切換);
低壓廠用電源系統(tǒng)和400VPC;
高壓啟/備變電源系統(tǒng)(2臺機共用);
柴油發(fā)電機組和保安電源(僅監(jiān)視);
直流系統(tǒng)和UPS系統(tǒng)(僅監(jiān)視);
自動同期系統(tǒng);
廠用電快切系統(tǒng)。
電氣主要保護(hù)安全自動裝置因要求DCS實現(xiàn)其功能目前尚有一定的難度,并且要增加相當(dāng)大的費用。原則上不要求通過DCS實現(xiàn)其功能,仍保留其裝置,但它們與DCS之間要有接口,常規(guī)方式采用硬接口。保留的保護(hù)自動專用裝置主要有如下:
發(fā)變組保護(hù)裝置;
自動準(zhǔn)同期裝置(ASS);
自動電壓調(diào)整裝置(AVR);
廠用電快切裝置;
故障錄波裝置。
主廠房外輔助系統(tǒng)的電氣系統(tǒng)如輸煤、化水、制氫、電除塵等暫不納入DCS系統(tǒng)中。
產(chǎn)品承諾:
保?證?全新原裝進(jìn)口,
保?證?安全準(zhǔn)時發(fā)貨,
保?證售后服務(wù)質(zhì)量,
優(yōu)勢價格,大量現(xiàn)貨。
主營DCS系統(tǒng)配件
機器人系統(tǒng)配件
大型伺服系統(tǒng)配件
品牌:ABB???,AB??,GE,FOXBORO,本特利,英維思,伍德沃德,西屋,瑞恩,施耐德,西門子,摩托羅拉,安川。力士樂。ACSO,橫河等進(jìn)口品牌。 專業(yè)銷售進(jìn)口DCS? PLC系統(tǒng)備件模塊
Triconex?Siemens?Yaskawa?ABB?GE?Ovation?AB?Foxboro?Motorola?Schneider?XYCOM?KUKA ? 專業(yè)銷售進(jìn)口DCS? PLC系統(tǒng)備件模塊 15天包退換 一年質(zhì)保 大量現(xiàn)貨? 國內(nèi)實力庫存商家
YXLON MU 231 XL X-RAY WHEEL INSPECTION SYSTEM
2010 Pax-DUO3D Digital Panoramic & 3D X-Ray System
2008 Sedecal APR-Veterinary X-Ray System
2007 DMX Works, Inc. Digital Motion X-Ray System
NEW I-MAX Touch Digital Dental Panoramic X-Ray System
CR Navigator Digital X-Ray Imaging System Equipment
NEW I-MAX Easy Digital Dental Panoramic X-Ray System
KODAK CR 120 DIGITAL VETERINARY X-RAY SYSTEM NEW
Heimann -Eagle Tall- X-Ray Inspection System
CINTEX FOOD X-RAY MACHINE model-L-400 CONVEYOR SYSTEM
Kavo Gendex Orthoralix 9200 Panoramic X-Ray System
Veeco XRF-2000AT X-Ray Measurement System
2008 Dexis Digital X-ray System
HI-SCAN 7555-A X-Ray Luggage Baggage Inspection System
X-Ray EG&G System 210
CMI 950S X-Ray System for Coating Thickness & Alloys
HP 43856A X Ray system
Nicolet NXR1400 X-Ray System
HP FAXITRON 43855A X-RAY SYSTEM MEDICAL X-RAY CABINET
J B 70 INTRAORAL X-RAY SYSTEM THAT IS SMARTER
HP 43855B X Ray system
X0020 Panoramic Corp. PC-1000 Pan X-Ray System
IDDC Model 1200 Porta Ray Portable X Ray System
L3 COMMUNICATIONS MODEL PX-M SERIES II X-RAY SYSTEM
HP 43855A X Ray System
Kodak 2100 Intraoral X-ray System
NEW Kodak 2100 DC Intraoral X-Ray System
Gendex Gx-Pan Dental Panoramic X Ray X-Ray xray System
LORAD Mammography M-IIE M-II-E X-RAY System Unit Mammo
Philips Medical Systems X-Ray Tube Housing Assembly
InnoVet Select Veterinary Radiographic X-Ray System
Siemens Stabilipan Orthovoltage Therapy X-Ray System
Used ScanRay Corp Torrex 150D X-Ray Inspection System
Varian Optical Tracking System X-Ray Digital Imaging
Portable Dental Digital Trophy X-Ray System
X-Ray System Fischer FX325R Complete & Works Great
DENTAL MEDICAL MOBILE CORIX 70 X-RAY SYSTEM
HP X-Ray System
EG&G Miniscan II X-ray Inspection System
EG&G ASTROPHYSICS MAIL BOX SECURITY X-RAY XRAY SYSTEM
DENTALEZ DENTAL X RAY SYSTEM HDX ,USED & OPERATIONAL
Mini Scan X-Ray Letter & Parcel Inspection System
X-Ray Camera System Thomson Tubes Electroniques
DentalEZ HDX X-Ray System
SPECIMEX DC X-ray System Government Surplus Shipped!!
Astrophysics Research Corp-X-Ray-Insp?ection-System
GE 700 Complete Dental X-ray System Intraoral 2-Systems
GE Medical Systems X-Ray, Mamo Camera Printer, 5130/240
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL B
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL B
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL B
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL B
AMD Athlon II X2 Desktop PC System w/BLUE RAY!
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
DENTAL MOBILE HIGH FREQUENCY X-RAY MACHINE SYSTEM
DENTAL MOBILE HIGH FREQUENCY X-RAY MACHINE SYSTEM
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
Dental Portable Mobile X – RAY Machine System Digital
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL MOBILE HIGH FREQUENCY X-RAY MACHINE SYSTEM
DENTAL PORTABLE MOBILE X RAY MACHINE SYSTEM w/DIGITAL
Single phase GE x-ray system
GE Medical Systems ZRLTXDMR Stereotix 2 X-RAY Equipment
AMD Athlon II X2 Desktop System BLUE RAY~TV Tuner Card!
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM DIGITAL P
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM DIGITAL
PHILIPS MEDICAL SYSTEM X-RAY TUBE SRO 2550 ROT 350
X-Ray IMAGE INTERPRETATION SYSTEM -Bausch-Lomb Scope
Enlarge
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
AMD Athlon II X2 Desktop System BLUE-RAY!
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
AMD Athlon II X2 (w/Blu-ray Rom Drive) Computer system
Dental X-Ray Gendex GX 900 Intra Oral System Parts
AMD Athlon II X2 Desktop System w/BLUE-RAY!
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
AMD Athlon II X2 2.8Ghz Desktop System w/BLUE-RAY!
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X – RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X-RAY MACHINE SYSTEM w/DIGITAL
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL c7
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL c8
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL c9
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL d1
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL e1
DENTAL PORTABLE MOBILE X- RAY MACHINE SYSTEM DIGITAL e3
PLC模塊,可編程控制器,CPU模塊,IO模塊,AI模塊,通訊模塊。AB/施耐德/ABB/GE/本特利/西屋/英維斯/霍尼韋爾/黑馬/FU克斯波羅
15天包退換 一年質(zhì)保 大量現(xiàn)貨? 國內(nèi)實力庫存商家