Fahimtar Rabuwar Fasaha Tsakanin Muhallan PLC da DCS
Programmable logic controllers suna ficewa a sarrafawar “discrete” mai sauri sosai. Suna iya sarrafa martani na milisakan ga na’urorin jigilar kaya, robot, da layukan marufi. Distributed control systems kuwa na musamman ne wajen daidaita madauki na analog. Suna sarrafa zafin jiki, matsa lamba, da kwarara ta amfani da algoridim na PID. Waɗannan dandamali biyu suna amfani da nau’o’in bayanai da suka bambanta. PLCs suna aiki ne a kan zagayen bincike na maimaituwa. Tsarin DCS suna amfani da aiwatarwa mai tuƙa-da-abubuwan-da-suka-faru (event-driven). ABB tana cike wannan babbar gibin ta hanyar matakan fassarar middleware.
Dalilin da ya Sa Hanyoyin Haɗa Kai na Gargajiya ke Gagari
Injiniyoyi da yawa suna ƙoƙarin yin “OPC tunneling” tsakanin na’urorin sarrafawa daban-daban. Wannan hanya tana aiki don sa ido kawai amma tana kasa ga sarrafawa da ke rufe madauki (closed-loop control). Jinkirin bayanai yana canzawa ba tare da tsari ba. Umarnin bawul na iya ɗaukar milisakan 50 a sakan guda, sannan milisakan 500 a gaba. Tsayin dakan tsarin aiki yana raguwa. ABB tana warware wannan ta hanyar zana samfuran aiwatarwa biyu cikin muhalli guda mai daidaitaccen lokaci. Zagayen bincike (scan cycles) suna daidaituwa a dukkan na’urorin sarrafawa.
Rawar Fasaha ta OPC UA a Cikin Haɗaɗɗen Tsari
ABB tana aiwatar da OPC UA tare da ƙarin PubSub. Wannan yana ba da damar sadarwar mai-buga-da-mai-saya a ainihin lokaci (real-time). Na’urorin filin suna watsa bayanai ba tare da buƙatar tambayar su (polling) ba. Amfanin faɗin hanyar sadarwa yana raguwa da 60%. Injiniyoyi suna saita tazarar biyan kuɗi (subscription intervals) bisa mahimmancin sigina. Na’urorin auna matsa lamba suna sabuntawa duk milisakan 50. Na’urorin auna zafin jiki suna sabuntawa duk daƙiƙa biyu. Wannan ikon sarrafawa a matakin sigina yana hana cunkoson hanyar sadarwa.
Bincike Mai Zurfi: Daidaita Madauki na Sarrafawa a Fadin Dandamali
Wata al’ada a masana’antar sarrafa aiki ita ce tana amfani da ɗaruruwan madauki na sarrafawa. Wasu madaukai suna cikin PLCs. Wasu kuma suna gudana a cikin na’urorin sarrafa DCS. Ba tare da haɗin kai ba, madauki na cascade da ke ketare iyakar dandamali suna haifar da rashin ƙarfi. Maganin ABB yana ƙirƙirar ƙirar sassan sarrafawa na kama-da-wane. Waɗannan sassan suna aiwatarwa a fadin na’urorin sarrafawa na jiki ba tare da tangarda ba.
Magance Bambancin Zagayen Bincike (Scan Cycle)
Yawanci PLCs suna duba madaukai duk milisakan 10 zuwa 50. Madauki na DCS sau da yawa suna aiwatarwa duk milisakan 100 zuwa 500. Musayar bayanai kai tsaye tana haifar da kuskuren daidaiton lokaci. ABB tana aiwatar da ma’ajiyar bayanai masu alamar lokaci. Kowane ƙima yana ɗauke da lokacin da aka samo shi. Na’urar sarrafawa da ke karɓa tana aiwatar da gyaran hasashe. Misali, PLC tana aika matakin tanki da alamar lokaci na milisakan 20. DCS tana ƙididdige matakin yanzu bisa ga saurin cikowa. Daidaiton sarrafawa yana ƙaruwa da 35% idan aka kwatanta da musayar bayanai kai tsaye ba tare da sarrafawa ba.
Daidaidaita Ƙararrawa da Abubuwan da Suka Faru
Dandamali daban-daban suna ware ƙararrawa ta hanyoyi daban. PLC na iya ɗaukar gazawar na’ura mai auna sigina a matsayin ƙaramin kuskure. Wannan yanayin ɗaya a DCS kuma na iya zama abin tayar da matakin rufewa mai tsanani. Wannan rashin daidaiton yana rikita masu aiki. ABB tana samar da haɓaɗɗen tushen bayanan ƙararrawa guda. Injiniyoyi suna daidaita matakan fifikon ƙararrawa a tsakanin tsarin daban-daban. Saiti guda ɗaya ne yake ayyana duk halayen ƙararrawa. Masu aiki suna ganin launuka da umarnin amsawa iri ɗaya ba tare da la’akari da na’urar sarrafawa da ta haifar da su ba.
Aiwtarwa ta Fasaha: Jagorar Injiniya Mataki-zuwa-Mataki
Wannan jerin matakan yana wakiltar tsarin tura aiki da ABB ta ba da shawara ga injiniyoyin sarrafa tsari.
Mataki na Ɗaya: Rarraba Sigina da Tag Mapping
Ƙirƙiri master tag list da ta haɗa duka maki na PLC da DCS. Rarraba kowane sigina bisa yawan sabunta shi da muhimmancinsa. High-speed digital inputs suna buƙatar scanning na milisekan 10. Analog process variables suna buƙatar sabuntawa na milisekan 200. Batch recipe parameters suna iya jure jinkirin daƙiƙa ɗaya. Ɗora kowane tag a cikin ajin fifikon sadarwa. Wannan rarrabawar ce ke ƙayyade yadda za a raba bandwidth na network.
Mataki na Biyu: Saitin Gateway da Redundancy
ABB tana amfani da masu kula da AC700F ko AC800M a matsayin integration gateways. Saita gateways biyu don muhimman tsare-tsare. Primary gateway yana gudanar da musayar bayanai na ainihin lokaci. Secondary yana aiki a hot standby. Failover yana kammala a cikin zagayowar scan guda. Sanya data buffering don ɗan katsewar network na wucin gadi. Buffer yana ajiye bayanan tsari na daƙiƙu 60. Babu asarar bayani a lokacin canjin tsarin aiki.
Mataki na Uku: Daidaita Lokaci a Fadin Domains
Sanya NTP server na musamman a kan control network. Saita dukkan PLCs, masu kula da DCS, da gateways su zama NTP clients. A cimma daidaiton lokaci ƙasa da milisekan guda. Yi amfani da IEEE 1588 Precision Time Protocol don aikace-aikacen da lokaci yake da matuƙar muhimmanci. Wannan daidaiton lokaci yana ba da damar daidai rikodin sequence-of-events. Masu aiki za su ga a sarari wane abin da ya faru ne ya fara tayar da matsala yayin nazarin kuskure.
Mataki na Huɗu: Dabarar Ƙaura da Logic
Kada ka ƙaura da dukkan logic a lokaci guda. Fara da logic blocks da ba su da interlock. Fara da sauƙaƙan lissafen analog. Gwada kowane block da aka ƙaura da halayyar asali. Yi amfani da kayan aikin ABB na kwatanta code domin tabbatar da aiwatarwa. Ƙaura da logic mai muhimmancin tsaro a ƙarshe. Gudanar da aiwatarwa a layi ɗaya na tsawon sa’o’i 168 kafin a cire tsofaffin controllers.
Mataki na Biyar: Raba Network zuwa Yankuna da Ƙarfafa Tsaro
Ƙirƙiri yankuna uku na network. Yanki na farko ya ƙunshi na'urorin filin aiki da I/O. Yanki na biyu yana ɗauke da masu kula da PLC da DCS. Yanki na uku yana masaukin kwamfutocin injiniya da historians. Sanya industrial firewalls a tsakanin yankuna. Tosa duk wani zirga-zirgar da ba ta da mahimmanci. Whitelist ɗin kawai tashoshin sadarwar ABB. Kunna tacewar adireshin MAC a kan managed switches. Waɗannan matakan suna hana haɗa na'urori ba bisa ƙa’ida ba.
Batutuwan Fasaha Masu Ci gaba Ga Injiniyoyi Masu Ƙwarewa
Magance Bumpless Transfer Tsakanin Dandamalin Kula da Tsari
Lokacin da ake ƙaura da wani loop daga PLC zuwa DCS, bai kamata fitarwa ta yi tsalle ba. ABB tana amfani da algorithm na tracking. Mai kula da tsarin da bai yi aiki ba yana bin fitarwar mai kula da tsarin da yake aiki. Duka biyun suna aiwatar da lissafe-lissafe iri ɗaya a lokaci guda. Lokacin da masu aiki suka miƙa ikon sarrafawa, fitarwa tana nan ba ta canza ba. Wannan dabara tana kare tsarin aiki daga rikicewa a lokacin ƙaura. Aiƙawa da karɓar bayanai ta bangarori biyu na buƙatar a yi su kowane milisekan 100.
Sarrafa Rarrabben I/O a Dukkan Wurare Masu Nisa
Manyan wurare suna da racks na I/O da aka baza su a tsawon kilomita da dama. Hanyoyin gargajiya suna amfani da igiyoyi dabam zuwa kowane mai sarrafawa. Tsarin ABB yana amfani da zobba na fiber optic. Modules na I/O suna haɗuwa da switch mafi kusa. Kowane mai sarrafawa na iya samun damar kowane maɓallin I/O. Wannan yana rage kuɗin igiyoyi da kashi 40%. Lokacin amsa ya ƙaru kaɗan amma ya ci gaba da kasancewa ƙasa da milisekand 50 ga muhimman maɓalli.
Hanyoyin Sadarwa Masu Maimaici don Samun Babban Samuwa
Saita zoben Ethernet guda biyu don muhimman tsare-tsare. Kowane zobe yana aiki ne dabam. Idan ɗaya daga cikin igiyoyi ya karye, zirga-zirga tana sake bi ta zobe na biyu. Warkewa tana kammaluwa cikin milisekand 50. Masu aiki ba sa ganin wani katsewa. Don matuƙar sahihanci, a ƙara madadin wayar salula. Tsarin yana sauyawa zuwa 4G idan duka zobba sun gaza. Wannan tsari yana kaiwa 99.999% uptime.
Nazarin Ayyukan Gaskiya na Injiniya tare da Cikakkun Bayanai na Fasaha
Tashar LNG: Haɗa Sarrafa Turbin da DCS na Shuka
Wani tashar LNG (liquefied natural gas) tana da sarrafa turbin a kan PLCs na musamman. Ayyukan shuka suna amfani da wani DCS dabam. Masu aiki ba za su iya daidaita lodin compressors da ƙimar liquefaction ba. ABB ta tura gateways AC800M tare da daidaita lokaci na milisekand 1. Siginar saurin turbin yanzu suna sabunta DCS kowane milisekand 50. DCS yana ƙirga rabon load mafi kyau a kan compressors guda huɗu. Sakamako: jimillar ƙarfin samar da shuka ya ƙaru da kashi 14%. Abubuwan compressor surge sun ragu da kashi 82%.
Tsarin Ruwa na Allura a Masana’antar Magunguna
Samar da WFI na buƙatar bin ka’idojin USP tare da ci gaba da sa ido. Shuka tana amfani da PLCs dabam-dabam ga kowane madauki na ruwa. Rubuta bayanai yana buƙatar shigar da su da hannu a cikin spreadsheet. ABB ta haɗa duk madaukai cikin System 800xA. Injiniyoyi sun saita inputs na analog 247 da duba su a kowane milisekand 200. Tarihin trends yanzu yana ajiye bayanan da aka tabbatar na shekaru goma. Lokacin shiri don audit ya ragu daga makonni uku zuwa awanni huɗu. Tsarin ya wuce binciken FDA ba tare da wata lura ba.
Sarrafa Muhallin Shagon Fentin Motoci
Yanayin zafin jiki da danshi a dakin feshin fenti suna shafar ingancin gamawa kai tsaye. Wurin yana amfani da PLCs don na’urorin sarrafa iska da DCS don robobin fenti. Gibin zafin jiki yana haifar da kayayyakin ƙyale. ABB ta aiwatar da cascade control a duk dandamali. DCS yana auna yanayin dakin feshin. Yana aika saiti (setpoints) zuwa PLC na na’urorin iska kowane milisekand 500. PLCs suna daidaita matsayin dampers a cikin milisekand 100. Bambancin zafin jiki ya ragu daga ±2.5°C zuwa ±0.7°C. Yawan lahani a fenti ya ragu da kashi 31%.
Hanyar Bel ɗin Jigilar Ma'adanai Mai Nisa
Bel ɗin jigilar kaya masu tsawon kilomita goma sha huɗu suna aiki ne dabam-dabam. Masu aiki ba su iya ganin rabon kayan a lokaci na ainihi. ABB ta shigar da zoben fiber optic tare da nodes na I/O 48. Kowane node yana haɗuwa da PLCs na yankin. DCS na tsakiya yana ƙirga saurin bel mafi dacewa bisa ga kwararar kaya. Jeren kunna bel yanzu yana daidaituwa a duk sassan. Amfanin wuta ya ragu da kashi 18%. Lalacewar bel ta ragu da kashi 23%.
Warware Mafi Yawan Matsalolin Haɗa Kai
Binciken Kurakuran Timeout na Sadarwa
Idan gateways suna bayar da rahoton timeouts, duba saitin maɓuɓɓugan cibiyar sadarwa (network switches) da farko. Yawancin switches suna da tsohon saitin kariyar guguwar watsawa (broadcast storm protection). Wannan fasalin na iya toshe zirga-zirgar OPC UA multicast. Kashe storm control a kan maɓuɓɓugan cibiyar sadarwa na sarrafa kansu kaɗai. Na gaba, tabbatar da saitin TCP keepalive. Sanya keepalive interval zuwa sakan 30. Ƙimomi sama da sakan 60 suna haifar da faɗakarwar timeout na ƙarya.
Magance Bambancin Nau’in Bayanai (Data Type Mismatches)
PLCs suna amfani da nau’ikan bayanai INT da REAL. Tsarin DCS galibi suna amfani da na’urorin injiniya na musamman (custom engineering units). Daidaita su kai tsaye yana haifar da kurakuran sikeli (scaling errors). ABB na ba da tubalan sauya na’urar injiniya (engineering unit conversion blocks). Sanya waɗannan tubalan da ƙimar sikeli mafi ƙasa da mafi sama. Misali, daidaita ƙididdigar PLC 0 zuwa 65535 zuwa matsin lamba na DCS 0 zuwa 100 bar. Gwada sauyawar da ƙima mafi ƙasa, ta tsakiya, da mafi girma kafin commissioning.
Gyara Jitter a Zagayen Scan
Jitter yana faruwa ne idan lokacin duba zagaye (scan time) yana sauyawa ba tare da tsari ba. Sanadin da aka fi samu: yawan interrupt routines. Matsa lambar da ba ta da muhimmanci zuwa ayyukan da aka tsara (scheduled tasks). Takaita kowace interrupt routine zuwa umarni (instructions) 50 kacal. Yi amfani da kayan aikin auna jitter na ABB don gano sassan lamba masu matsala. Nufa iyakar jitter ƙasa da kashi 5% na lokacin scan don aikace-aikacen sarrafa tsari.
Tambayoyi da ake yawan yi daga tawagogin injiniyoyi
Me ke faruwa idan integration gateway ta rasa wuta?
ABB gateways suna tallafa wa tushen wuta masu maimaituwa (redundant power supplies). Kowanne gateway yana karɓar shigar 24V DC biyu daga tushe daban-daban. Idan dukkan shigar wuta biyu sun faɗi, gateway ɗin yana ajiye bayanai a ƙwaƙwalwar da ba ta gogewa (non-volatile memory). Da zarar an sake kunnawa, gateway ɗin yana ci gaba da musayar bayanai cikin sakan 15. Na’urorin filin (field devices) suna ci gaba da sarrafa gida yayin katsewar. Ba a kashe ayyukan tsaro ko ɗaya ba.
Za mu iya haɗa nau’ukan na’urar sarrafawa (controller families) daban-daban na ABB cikin tsari ɗaya?
I. ABB's Unified Engineering environment tana tallafa wa AC500 PLCs, AC800M na’urorin sarrafawa masu ƙarfi, da System 800xA DCS. Injiniyoyi suna shirya (program) duk dandamali da irin kayan aikin software ɗaya. Ana iya canja dakunan lambar (code libraries) tsakanin nau’ukan na’urorin sarrafawa. Wannan yana ba da damar gina tsarin da zai iya faɗaɗa (scalable architecture). Ƙananan skids suna amfani da AC500. Babban yankunan aikin tsari suna amfani da AC800M. DCS na tsakiya ne ke tsara komai.
Ta yaya za mu tantance aikin haɗa kai kafin a fara aikin shuka (plant startup)?
ABB na samar da kwaikwayon hardware-in-the-loop. Haɗa na’urar sarrafawa ta ainihi da samfurorin aikin tsari na kwaikwayo. Saka kurakurai (faults) ka kuma lura da yadda tsarin ke amsawa. Gwada mafi muni nauyin zirga-zirgar cibiyar sadarwa (network load) da na’urorin ƙirƙirar zirga-zirga (traffic generators). Tabbatar da yanayin canza iko (failover) ta hanyar cire kebul da wutar lantarki. Kammala gwajin aiki na sa’o’i 72 a jere ba tare da kuskure ba. Wannan kwaikwayon yana gano kusan kashi 95% na matsalolin haɗa kai kafin a kai tsarin filin aiki.
