FUNKCIONALNA ANALIZA SODOBNIH NADZORNIH SISTEMOV SCADA

Zorko, Blaž (author), Humar, Iztok (mentor)

Sistemi avtomatizacije v industriji in stavbah sestojijo iz štirih nivojev opreme, in sicer iz perifernega, krmilnega, nadzornega in informacijskega nivoja. Nadzorni sistemi (SCADA – Supervisory Control And Data Acquisition) so glavno orodje operaterjev za spremljanje in upravljanje s procesi. Na trgu danes obstaja veliko število nadzornih sistemov in ob današnjem hitrem razvoju le-teh, se pri uporabnikih, kakor tudi pri projektnih inženirjih, velikokrat pojavlja vprašanje, kaj zmorejo nadzorni sistemi, kakšne so razlike med njimi, kakšne možnosti sploh obstajajo. V tej nalogi je obravnavanih pet predstavnikov nadzornih sistemov, ki so prisotni na trgu, in hkrati zagotavljajo dovolj visoko stopnjo kvalitete. Trendi razvoja perifernega in krmilnega nivoja grejo v smeri, da postajajo tudi na tem nivoju elementi vedno bolj “multifunkcionalni”. Tako npr. senzor ni več zgolj merilni, temveč tudi komunikacijski element, krmilnik pa ni več zgolj krmilnik, ampak je velikokrat hkrati tudi preprost nadzorni sistem, največkrat s pomočjo vgrajenega WEB strežnika. Programiranje krmilnikov postaja vedno bolj dovršeno. Tako vse več dobaviteljev ponuja funkcionalnosti kot npr., da se na krmilnem nivoju izbere ena od ponujenih aplikacij in programska oprema avtomatsko izvede tudi programsko logiko, ki jo lahko potem programer poljubno predela. Ta rešitev se na primer pri Desigo krmilnikih imenuje “Get Datapoints and Logic from a Solutionˮ. Komunikacijske protokole nadzornih sistemov najlažje razdelimo v dve skupini: industrijski komunikacijski protokoli in industrijski protokoli stavbne avtomatike. Najbolj uveljavljeni industrijski komunikacijski protokoli so Ethernet, Modbus in Profibus, komunikacijski protokoli stavbne avtomatike pa BACnet in LON. Razlika med njimi je, da industrijski komunikacijski protokoli prenašajo preproste podatke, kot so bit, byte, Word, itd. Komunikacijski protokoli stavbne avtomatike pa prenašajo kompleksne podatkovne objekte kot npr. urnik, ki so sestavljeni iz več podatkov, ne zgolj iz ene vrednosti. Za izmenjavo podatkov med nadzornimi sistemi različnih proizvajalcev že vrsto let prevladuje OPC protokol preko Ethernet-a. Kar se tiče ekranskih prikazov oziroma grafičnih pregledovalnikov in urejevalnikov, vsi obravnavani nadzorni sistemi zagotavljajo dinamizirane objekte, knjižnice objektov in simbolov, Desigo CC pa ima najnaprednejši inženiring s funkcijo t.i. “Associated Graphicsˮ, ki z vnosom podatkovne točke na sliko sama poda tudi najbolj primeren grafični simbol. Desigo CC ponuja tudi povsem nov princip upravljanja za operaterje s petimi okni, med katerimi je tudi “System Browserˮ, ki je podoben raziskovalcu v Windows-ih. Razlika med obravnavanimi nadzornimi sistemi je tudi v številu podprtih tipov grafičnih datotek, ki se lahko direktno uvozijo v ekranske prikaze. Vsi obravnavani nadzorni sistemi imajo dovršeno zgodovino oziroma shranjevanje vrednosti meritev in dogodkov, pri čemer je povsod osnova za shranjevanje “Microsoft SQLˮ baza podatkov. Dobavitelji nadzornih sistemov stavbne avtomatike že več let zagotavljajo shranjevanje podatkov tudi na nivoju krmilnikov (t.i. “Offline Trendsˮ), dobavitelji nadzornih sistemov industrijske avtomatike pa so začeli implementirati to funkcionalnost v zadnjem času. Vsi nadzorni sistemi so se pravočasno prilagodili zahtevam trga in omogočajo t.i. energetska poročila, ki so glavno orodje za spremljanje in optimizacijo porabe energije. V osnovi energetska poročila omogočajo prikaz grafov porabe energentov in izvoz podatkov v datoteke, največkrat v excel. Izjema je le Desigo CC, pri katerem bodo energetska poročila na voljo šele v verziji MP3.0. Podobno lahko trdimo tudi za zagotavljanje skladnosti z zahtevami v farmacevtski industriji. Vsi obravnavani nadzorni sistemi omogočajo sledenje spremembam z zaščiteno bazo podatkov (t.i. “Audit Trailˮ) in elektronsko podpisovanje. To je izvedeno z instalacijo dodatnih programskih modulov oziroma aplikacij in ni del osnovnega programa nadzornega sistema. Izjema bo Desigo CC, kjer bo to implementirano znotraj edine aplikacije, vendar šele z verzijo MP3.0. Glavna razlika med nadzornim sistemom Desigo CC in ostalimi obravnavanimi nadzornimi sistemi je, da je Desigo CC zasnovan na t.i. “One Layerˮ konceptu, kar pomeni, da so vse funkcije in možnosti implementirane znotraj ene in edine aplikacije. Pri ostalih nadzornih sistemih pa obstaja več dodatnih programskih modulov oziroma aplikacij (t.i. “Multi Layerˮ koncept), s katerimi se zagotovi dodatne funkcionalnosti, kot so npr. energetska poročila, skladnost s farmacevtskim standardom 21 CFR Part 11 itd. Desigo CC je tudi nadzorni sistem, ki prinaša revolucionaren koncept glede integracije različnih disciplin stavbne avtomatike. Do nedavnega so bili požarni sistem, video nadzor, kontrola pristopa itd. strogo ločeni od nadzornega sistema za klimatizacijo in ogrevanje. Desigo CC je združil vse discipline znotraj ene aplikacije, kar prinaša številne poenostavitve za operaterje. Obravnavani nadzorni sistemi zagotavljajo še številne funkcije, ki jih sodoben nadzorni sistem mora imeti: pregledovalnik alarmov in dogodkov, WEB strežnik, strežnik/odjemalec arhitekture sistema, večnivojska zaščita dostopa do sistemov in objektov, generator običajnih poročil itd. Na trgu se pojavlja tudi vse več enostavnih, včasih celo brezplačnih nadzornih sistemov, ki že ponujajo vse osnovne funkcionalnosti, ki jih ima sodoben nadzorni sistem. V tem delu so obravnavani trije taki, in sicer ACS790, N152 in OZW772. Pojav tovrstnih nadzornih sistemov je vzpodbuda večjim dobaviteljem nadzornih sistemov k novim in naprednejšim idejam in rešitvam. Nedvomno bo razvoj nadzornih sistemov še silovit in bo potekal v koraku z razvojem računalniške tehnologije in industrije. Predvideva se polna podpora mobilnim aplikacijam, podpora vsem standardnim protokolom preko etherneta, poenostavitev elektronskega podpisovanja in elektronskih poročil, poenostavljen “One Layer” aplikacijski model, kar pomeni, da bo nadzorni sistem ena sama aplikacija, ki zmore vse. V tem delu so podani še predlogi za izboljšave kot npr. podpora Konnex komunikacijskemu protokolu preko etherneta, zanesljiva zaščita pred nepooblaščenim kopiranjem izvorne kode, standardizacija podprtih grafičnih datotek itd. Dejstvo pa je, da se razvoja natančno ne da predvideti. Poleg tehnološkega vidika bo imela zelo velik vpliv na razvoj nadzornih sistemov tudi globalna ekonomija.

• Language: Slovenian
• Keywords: Ključne besede: nadzorni sistemi, iFix, Nova Pro Open, WinCC, Desigo Insight, Desigo CC, industrijski nadzorni sistemi, nadzorni sistemi stavbne avtomatike, “One Layer” koncept, itd.
• Work type: Master's thesis
• Organization: FE - Faculty of Electrical Engineering
• Year: 2016
• PID: 20.500.12556/RUL-84936
• Publication date in RUL: 08.09.2016

Secondary language

• Language: English
• Title: FUNCTIONAL ANALYSIS OF MODERN SUPERVISORY SYSTEMS SCADA

Abstract

Automation systems in industry and in buildings consist of four levels of equipment which are peripheral level, control level, monitoring level and information level. Supervisory systems (SCADA- Supervisory Control and Data Acquisition) are the main tool for operators to monitor and manage processes. On the market today there is a large number of SCADA systems. Users and also project engineers are often asking themselves what can supervisory systems do today, what are the differences between them, what options do exist. In this work we compare five SCADA systems which are present on the market today and are providing high degree of quality. Development of peripheral and control level goes in direction that elements on this level are becoming more and more sophisticated as well. A sensor is not any more just a measuring device but also a communicating device, controller is not any more just a device for logic but also a small supervisory system, usually providing simple WEB server, etc. Programming of controllers is becoming more and more sophisticated. Many producers of controllers are providing option that programmer can choose a preprogrammed application and the programming software itself produces a logic program which can be freely adapted by programmer. In Desigo controllers portfolio this solution is called “Get Datapoints and Logic from a Solution”. Communication protocols of supervisory systems can be easilly divided into two groups: industrial communication protocols and protocols of building automation. The most spread industrial protocols are ethernet, Modbus and Profibus while communication protocols of building automation are mostly BACnet and LON. The main difference between this two groups is that industrial communication protocols are mostly transferring simple data types like “bit”, “byte”, “word” and the protocols of building automation are using complex datatypes like “Time scheduler” which consists of many simple data types, not just of one value. For communication between supervisory systems of different suppliers OPC protocol over ethernet is mostly used. All five supervisory systems in this document are providing dynamised graphic symbols and graphic libraries but Desigo CC has the most advanced engineering with so called “Associated Graphics” function which creates a graphic symbol on a picture with simple drag and drop of a single BACnet objet (variable). Desigo CC is providing also completely new principle of managing systems for operators with five windows. Difference between this five analysed supervisory systems is also in the number of graphical file formats that can be directly imported into the picture. All supervisory systems have also powerfull trends (so called archives of alarms, events and measured values). All of them are using Microsoft SQL database. Producers of building automation supervisory systems are providing so called “Offline Trends” for many years, while producers of industrial supervisory systems are providing “Offline Trends” only recently. Offline trend means that values are being stored also in controllers, not just in a supervisory system. At the same time all supervisory systems have been adjusted to requirements of the market and are offering so called “Energy Reports” which are main tool for energy management and optimisation. Basically energy reports are providing graphs of energy consumption and costs and are offering also data export into file formats like “excel”. In Desigo CC Energy reports will be available with version MP3.0. Simillary is with compliance with standard for pharmaceutical industry (21 CFR Part 11). All analysed supervisory systems are providing audit trail with protected database and electronic signatures. This is realised with installation of additonal program modules (applications) and is not part of main application of supervisory system. Exception here is Desigo CC which will provide compliance with pharmaceutical standard within the only application – Desigo CC. The main differnce betweend Desigo CC and the other supervisory systems is that Desigo CC is based on so called “One Layer” concept which means that all functions are implemented within one and only application. Other supervisory systems consist of many program modules (so called “Multi Layer” concept) which provide required functionallities like energy reports, compliance with pharmaceutical industry standard 21 CFR Part 11, etc. Desigo CC is also supervisory system which brings new revolutionary concept regarding integration of different disciplines of building automation. Fire, security and video supervisory systems were recently strictly separated from supervisory system for heating and ventilation. Desigo CC has joined all disciplines within one and only application which brings many benefits for operators. All analysed supervisory systems are providing also many other functions that supervisory system must have like alarm and event viewer, WEB server, client/server architecture of the system, multi level access control, report generator, etc. On the market there are more and more simple supervisory systems which are sometimes even free of charge but at the same time they are offering all basic functionallities that modern supervisory system has. In this work three of such systems are discussed: ACS790, N152 and OZW772. Appearance of such supervisory systems is pushing bigger players on the market to develop new ideas and solutions to keep the main role on the market. Development of supervisory systems will follow the development of computer technology and industry. Supervisory systems will have to provide full support for mobile applications, give support to all standard protocols over ethernet, simplify electronic signatures and electronic reports and probably follow “One Layer” application model which means that supervisory system will be only one application which will be capable of all functionallities. In this work are presented some conclusions and suggestions for improvement like support of Konnex communication protocol over ethernet, advanced security protection of source code against unauthorized access, support of standard graphic file formats, etc. But the fact is that the development of supervisory systems can not be precisely foreseen. Beside the influence of technological development also global economy will have strong impact on development of the supervisory systems.

• Keywords: Keywords: SCADA systems, iFix, Nova Pro Open WinCC, Desigo Insight, Desigo CC, industrial supervisory systems, supervisory systems for building automation, “One Layer” concept, etc.