Multi-Agent System Based Distributed Voltage Control in Distribution Systems

Distribution System is a standout among the most complex entities of the electric power grid. Moreover, voltage quality sustainability till customer premises, with the introduction of Distributed Generation (DG), is one of the most frenzied control areas. Previously, SCADA in cohesion with Wide Area Measurement Systems (WAMS) was a dependable control strategy, yet as the ever growing and complex distribution system is advancing towards the Smart Grids, control strategies are becoming more and more distributed in spite of the centralized one. A detailed literature review of the voltage control methods ranging from the centralized one to the fully distributed agent based control is conducted. In the light of the previous researches, a distributed voltage control based on Multi-Agent System is proposed, as the agents based control strategies, are becoming well known day by day, due to its autonomous control and decision making capacity. To make the proposed algorithm fully distributed, token transversal through the network and agents communication to remove voltage violation over least correspondence and measurements of the system, are utilized. Following instant voltage control at the load nodes, a penalty function is employed to keep the voltage value curve throughout the network as close as possible to the nominal, with minimum network losses and minimum voltage damage. The authentication of the devised control algorithm is acknowledged by utilizing a Greenfield distribution Network, which is based on the realistic loading data. Agents and the controlling logic are codded in Matlab ® programming software. A sensitivity analysis is performed based on DG penetration to have the complete overview of the proposed methodology. The principle objective of the technique is to keep the voltage value within the standard limit of ±10% of the nominal, at all load nodes while instantly utilizing voltage control entities like DGs, Static VAR Compensator (SVCs) and On-Load Tap Changer (OLTC). In addition, the optimization of network losses and voltage level close to nominal is to be accomplished by the penalty function implementation

Agentno razvojno okružje za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima

A human settlement may exist in an environment which does not allow the use of central resource distribution systems such as national electrical grid, municipal water supply, etc., or where the use of such systems is not preferable by its inhabitants. In such scenarios, there is a need for managing resources that are being produced, stored, and consumed, within the boundaries of such settlements, with a goal to maintain the self-sustainability of such settlement. Settlements are hereafter considered self-sustainable if sufficient resource quantities are available in the observed time period, with regard to defined comfort levels and observed resource type.Considering existing work in the fields of smart cities, self-sustainable settlements, smart grids,Internet of things and existing intelligent agent infrastructures tackling renewable resource management, new agent classes, behaviours and protocols are proposed. A central part of the dissertation work includes developing specialized agent classes and behaviours that would allow to model and simulate the dynamics of a local resource production, storage and consumption in order to pursue and evaluate self-sustainability of the settlement.Such framework could be used by a modeler either to design and simulate a new self-sustainable system, or to evaluate and analyze an existing system, which could lead to considerable improvements in the design of a settlement and its resource production, consumption and storage elements, in regard to the context of self-sustainability.Cilj istraživanja je modelirati i simulirati samoodrživa ljudska naselja u novorazvijenom razvojnom okružju za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima temeljenom na agentima, sa svrhom produljenja samoodrživosti naselja. U tom kontekstu, identificirani su sljedeći istraživački ciljevi:1. Razviti nove klase agenata, ponašanja i protokola specijaliziranih za modeliranje i simulacije upravljanja resursima u pametnim samoodrživim ljudskim naseljima.2. Integrirati novo razvijene klase agenata, ponašanja i protokola u funkcionalno razvojno okružje za modeliranje i simulaciju.3. Razviti ne-trivijalno kompleksne scenarije za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima. Scenariji će biti razvijen i unutar tri kategorije: permakulturno eko-selo, vanzemaljska kolonija, svemirsko putovanje.Hipoteza disertacije je sljedeća:H1. Razvojno okruženje za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima temeljeno na agentima produžiti će vremenski period samoodrživosti prilikom korištenja u razvijenim testnim scenarijima.Prvo poglavlje je uvodno i elaborira kontekst istraživanja u konciznom obliku, predstavljajući istraživačke ciljeve i hipotezu.Poglavlje 2 detaljizira istraživanje, od inicijalnog koncepta okružja, prema gradnji okružja i implementaciji, dajući uvid u detalje implementacije i korištene istraživačke metode.Poglavlje 3 pruža pregled literature područja relevantnih za istraživanje, kao što su održivi razvoj, samoodrživa ljudska naselja, agenti i više-agentni sustavi, inteligentne zgrade, pametni gradovi, eko-povratne informacije, upravljanje vršnim opterećenjem, te drugih povezanih područja.Poglavlje 4 prezentira implementaciju razvojnog okružja. Slijedeći prilagođeni tok rada MaSEmetodologije, u prvim koracima identificiraju se zahtjevi sustava, prema kojima se deriviraju ciljevi sustava. Ciljevi se nakon toga koriste u kreiranju agentnih uloga, a uloge se potom koristeza definiciju klasa agenata.Globalni cilj razvojnog okruženja je sljedeći:Nakon izvršenih aktivnih napora usmjerenih u svrhu ostvarenja samoodrživosti modeliranog sustava, informiraj korisnika o tome da li je sustav samoodrživ; ukoliko modelirani sustav nije samoodrživ, usmjeri korisnika na relevantne probleme koji sprječavaju samoodrživost.Isto poglavlje elaborira modele konzumacije resursa i mehanizme samoodrživosti. Mehanizmi samoodrživosti izvedeni su iz literature povezanih i relevantnih područja istraživanja, iz intervjua provedenih sa ekspertima za samoodrživost, iz stvarnih mehanizama koje koristeprimjerice poduzeća za energetiku, te iz poznavanja načina rada velikog broja jedinica zapotrošnju energije, analize i vlastitih iskustava.Poglavlje 5 elaborira način korištenja razvojnog okružja prilikom modeliranja i simulacija specifičnih sustava. Pojašnjene se ulazne i izvještajne varijable koje korisnik koristi za modeliranje, prilagodbu i analizu sustava.Poglavlje 6 opisuje razvijene testne scenarije, rezultate simulacija nad tim scenarijima, te analizu i diskusiju. Scenariji su inicijalno simulirani bez korištenja mehanizama za samoodrživost, koristeći jednostavne matematičke formule u alokaciji resursa. Nakon toga,scenariji su simulirani nad identičnim ulaznim podacima koristeći mehanizme za samoodrživost razvojnog okružja. Rezultati provedenih simulacija pokazali su da je razvojnookružje produžilo trajanje samoodrživosti u svakom od razvijenih scenarija, što je konzistentnosa istraživačkom hipotezom H1.U poglavlju 7 zaključuje se istraživanje, diskutira o rezultatima simulacije, te se predlažuplanovi za daljnje istraživanje

Agentno razvojno okružje za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima

A human settlement may exist in an environment which does not allow the use of central resource distribution systems such as national electrical grid, municipal water supply, etc., or where the use of such systems is not preferable by its inhabitants. In such scenarios, there is a need for managing resources that are being produced, stored, and consumed, within the boundaries of such settlements, with a goal to maintain the self-sustainability of such settlement. Settlements are hereafter considered self-sustainable if sufficient resource quantities are available in the observed time period, with regard to defined comfort levels and observed resource type.Considering existing work in the fields of smart cities, self-sustainable settlements, smart grids,Internet of things and existing intelligent agent infrastructures tackling renewable resource management, new agent classes, behaviours and protocols are proposed. A central part of the dissertation work includes developing specialized agent classes and behaviours that would allow to model and simulate the dynamics of a local resource production, storage and consumption in order to pursue and evaluate self-sustainability of the settlement.Such framework could be used by a modeler either to design and simulate a new self-sustainable system, or to evaluate and analyze an existing system, which could lead to considerable improvements in the design of a settlement and its resource production, consumption and storage elements, in regard to the context of self-sustainability.Cilj istraživanja je modelirati i simulirati samoodrživa ljudska naselja u novorazvijenom razvojnom okružju za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima temeljenom na agentima, sa svrhom produljenja samoodrživosti naselja. U tom kontekstu, identificirani su sljedeći istraživački ciljevi:1. Razviti nove klase agenata, ponašanja i protokola specijaliziranih za modeliranje i simulacije upravljanja resursima u pametnim samoodrživim ljudskim naseljima.2. Integrirati novo razvijene klase agenata, ponašanja i protokola u funkcionalno razvojno okružje za modeliranje i simulaciju.3. Razviti ne-trivijalno kompleksne scenarije za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima. Scenariji će biti razvijen i unutar tri kategorije: permakulturno eko-selo, vanzemaljska kolonija, svemirsko putovanje.Hipoteza disertacije je sljedeća:H1. Razvojno okruženje za modeliranje i simulaciju upravljanja resursima u pametnim samoodrživim ljudskim naseljima temeljeno na agentima produžiti će vremenski period samoodrživosti prilikom korištenja u razvijenim testnim scenarijima.Prvo poglavlje je uvodno i elaborira kontekst istraživanja u konciznom obliku, predstavljajući istraživačke ciljeve i hipotezu.Poglavlje 2 detaljizira istraživanje, od inicijalnog koncepta okružja, prema gradnji okružja i implementaciji, dajući uvid u detalje implementacije i korištene istraživačke metode.Poglavlje 3 pruža pregled literature područja relevantnih za istraživanje, kao što su održivi razvoj, samoodrživa ljudska naselja, agenti i više-agentni sustavi, inteligentne zgrade, pametni gradovi, eko-povratne informacije, upravljanje vršnim opterećenjem, te drugih povezanih područja.Poglavlje 4 prezentira implementaciju razvojnog okružja. Slijedeći prilagođeni tok rada MaSEmetodologije, u prvim koracima identificiraju se zahtjevi sustava, prema kojima se deriviraju ciljevi sustava. Ciljevi se nakon toga koriste u kreiranju agentnih uloga, a uloge se potom koristeza definiciju klasa agenata.Globalni cilj razvojnog okruženja je sljedeći:Nakon izvršenih aktivnih napora usmjerenih u svrhu ostvarenja samoodrživosti modeliranog sustava, informiraj korisnika o tome da li je sustav samoodrživ; ukoliko modelirani sustav nije samoodrživ, usmjeri korisnika na relevantne probleme koji sprječavaju samoodrživost.Isto poglavlje elaborira modele konzumacije resursa i mehanizme samoodrživosti. Mehanizmi samoodrživosti izvedeni su iz literature povezanih i relevantnih područja istraživanja, iz intervjua provedenih sa ekspertima za samoodrživost, iz stvarnih mehanizama koje koristeprimjerice poduzeća za energetiku, te iz poznavanja načina rada velikog broja jedinica zapotrošnju energije, analize i vlastitih iskustava.Poglavlje 5 elaborira način korištenja razvojnog okružja prilikom modeliranja i simulacija specifičnih sustava. Pojašnjene se ulazne i izvještajne varijable koje korisnik koristi za modeliranje, prilagodbu i analizu sustava.Poglavlje 6 opisuje razvijene testne scenarije, rezultate simulacija nad tim scenarijima, te analizu i diskusiju. Scenariji su inicijalno simulirani bez korištenja mehanizama za samoodrživost, koristeći jednostavne matematičke formule u alokaciji resursa. Nakon toga,scenariji su simulirani nad identičnim ulaznim podacima koristeći mehanizme za samoodrživost razvojnog okružja. Rezultati provedenih simulacija pokazali su da je razvojnookružje produžilo trajanje samoodrživosti u svakom od razvijenih scenarija, što je konzistentnosa istraživačkom hipotezom H1.U poglavlju 7 zaključuje se istraživanje, diskutira o rezultatima simulacije, te se predlažuplanovi za daljnje istraživanje

Automated validation of minimum risk model-based system designs of complex avionics systems

Today, large civil aircraft incorporate a vast array of complex and coupled subsystems with thousands of electronic control units and software with millions of lines of code. Aircraft suppliers are challenged to provide superior products that are developed at a minimum time and cost, with maximum safety and security. No single person can understand the complex interactions of such a system of systems. Finding an optimal solution from large sets of different possible designs is an impossible task if done manually. Thus, written, non-executable specifications carry a high degree of product uncertainty. As a result, more than two-thirds of all specifications need to be reworked. Since most specification flaws are discovered and resolved at a late stage during development, when expenditures for redesign are at a maximum, the development approach currently used has a high probability of project cost and time overruns or even project failure, thus maximizing the risk of development. It is the aim of this work, to develop a model- and simulation-based systems engineering method with associated design and validation environment that minimizes the risk of development for complex systems, e.g. aircraft. The development risk is a minimum, if all development decisions are validated early against the services of a product at mission level by the final customer. To do so, executable specifications are created during design and validated against the requirements of system services at mission level. Validated executable specifications are used and updated for all decisions from concept development through implementation and training. In addition, virtual prototypes are developed. A virtual prototype is an executable system specification that is combined with human machine interface concept models to include usability requirements in the overall design and to enable interactive specification validation and early end user training by means of interactive user-driven system simulation. In a first step, so called executable workflows and simulation sets are developed to enable the execution of sets of structured and coupled simulation models. In a second step, a model- and simulation-based development and validation process model is developed from concept design to specification development. In a final step, two different validation processes are developed. An automated validation process based on executable specifications and an interactive validation process based on virtual prototypes. For the development of executable specifications and virtual prototypes, plug-and-play capable model components are developed. The developed method is validated for examples from civil aircraft development with focus on avionics and highly configurable and customizable cabin systems.Große zivile Flugzeuge umfassen eine hohe Anzahl von komplexen und gekoppelten Subsystemen mit Tausenden von elektronischen Steuergeräten und Software mit Millionen von Codezeilen. Keine einzelne Person kann die komplexen Wechselwirkungen eines solchen Systems von Systemen verstehen. Daher beinhalten geschriebene, nicht ausführbare Spezifikationen einen hohen Grad an Produktunsicherheit. Infolgedessen müssen mehr als zwei Drittel aller Spezifikationen überarbeitet werden. Da die meisten Spezifikationsfehler zu einem späten Zeitpunkt entdeckt und gelöst werden, wenn Aufwände für Überarbeitungen maximal sind, hat der gegenwärtige Entwicklungsansatz eine hohe Wahrscheinlichkeit für Kosten- und Zeitüberschreitungen oder führt zum Fehlschlagen von Projekten. Hierdurch wird das Entwicklungsrisiko maximiert. Es ist das Ziel dieser Arbeit, eine modell- und simulationsbasierte Entwicklungsmethode mit zugehöriger Entwurfs- und Validierungsumgebung zu entwickeln, welche das Risiko der Entwicklung für komplexe Systeme minimiert. Das Entwicklungsrisiko ist minimal, wenn alle Entwicklungsentscheidungen frühzeitig vom Endkunden gegen die Leistungen eines Produktes auf Missionsebene validiert werden. Dazu werden ausführbare Spezifikationen während des Entwurfs erstellt und anhand der Anforderungen auf Missionsebene validiert. Validierte ausführbare Spezifikationen werden für alle Entscheidungen von der Konzeptentwicklung bis zur Implementierung verwendet und aktualisiert. Darüber hinaus werden virtuelle Prototypen entwickelt, welche ausführbare Spezifikationen mit Konzeptmodellen für Mensch-Maschine-Schnittstellen kombinieren, um Usability-Anforderungen in den Gesamtentwurf aufzunehmen. Dies ermöglicht eine interaktive Validierung sowie frühes Endbenutzertraining mittels benutzergesteuerter Systemsimulation. Es werden ausführbare Arbeitsabläufe und Simulation Sets entwickelt, welche die Ausführung von strukturierten und gekoppelten Simulationsmodellen ermöglichen. Anschließend wird ein modell- und simulationsbasiertes Entwicklungs- und Validierungsprozessmodell vom Konzeptdesign bis zur Spezifikationsentwicklung entwickelt. Hierfür werden zwei verschiedene Validierungsprozesse verwendet. Ein automatisierter Validierungsprozess basierend auf ausführbaren Spezifikationen und ein interaktiver Validierungsprozess basierend auf virtuellen Prototypen. Für die Entwicklung von ausführbaren Spezifikationen und virtuellen Prototypen werden Modellkomponenten entwickelt. Die entwickelte Methode wird mithilfe von Beispielen aus der zivilen Flugzeugentwicklung validiert, insbesondere in Hinblick auf Avionik sowie hoch konfigurierbare und anpassbare Kabinensysteme