Hardware-in-the-Loop Co-Simulation Based Validation of Power System Control Applications

Renewables are key enablers for the realization of a sustainable energy supply but grid operators and energy utilities have to mange their intermittent behavior and limited storage capabilities by ensuring the security of supply and power quality. Advanced control approaches, automation concepts, and communication technologies have the potential to address these challenges by providing new intelligent solutions and products. However, the validation of certain aspects of such smart grid systems, especially advanced control and automation concepts is still a challenge. The main aim of this work therefore is to introduce a hardware-in-the-loop co-simulation-based validation framework which allows the simulation of large-scale power networks and control solutions together with real-world components. The application of this concept to a selected voltage control example shows its applicability.Comment: 2018 IEEE 27th International Symposium on Industrial Electronics (ISIE

Simulation-based validation of smart grids – Status quo and future research trends

Smart grid systems are characterized by high complexity due to interactions between a traditional passive network and active power electronic components, coupled using communication links. Additionally, automation and information technology plays an important role in order to operate and optimize such cyber-physical energy systems with a high(er) penetration of fluctuating renewable generation and controllable loads. As a result of these developments the validation on the system level becomes much more important during the whole engineering and deployment process, today. In earlier development stages and for larger system configurations laboratory-based testing is not always an option. Due to recent developments, simulation-based approaches are now an appropriate tool to support the development, implementation, and roll-out of smart grid solutions. This paper discusses the current state of simulation-based approaches and outlines the necessary future research and development directions in the domain of power and energy systems. © Springer International Publishing AG 2017acceptedVersio

Co-simulação de rede para internet das coisas

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáA construção da rede co-simulada (rede física e rede simulada) dessa tese, será uma base para o desenvolvimento de técnicas de simulação usando a plataforma OMNeT++ (computacional) com dispositivos sensores (físicos). Uma vez estabelecida a plataforma, seria possível estender o funcionamento da rede para outros ambientes, como é o caso do desenvolvimento de redes físicas na mineração. Nesse sentido podemos construir uma rede física, e simular o comportamento de outros componentes e redes utilizando o OMNeT++. Como esse trabalho utiliza IoT para o desenvolvimento da topologia proposta, esse trabalho acaba corroborando na utilização de aparelhos com baixa potência. O objetivo desta dissertação é mostrar em um ambiente real a utilização de co-simulação com o OMNeT++ de forma a validar a plataforma criada para a produção de simulações de redes IoT. De tal forma será possível mostrar que a co-simulação funciona adequadamente no ambiente de simulações OMNeT++, e fornecer uma base para eventuais futuras expansões. Basicamente temos um conjunto de componentes que estarão conectados entre si sem fios (criando uma RSSF), que estarão ligados (através de TCP/IP) a um computador executando OMNeT++, o qual suporta uma topologia de rede IP criada dentro do simulador. Deste modo é criada uma rede completa de dispositivos, tanto simulados, quanto físicos, e que pode ser usada para recolher resultados estatísticos do seu desempenho, nomeadamente dentro do OMNeT++. Tivemos como resultado de recepção de pacotes em média 64,4%, demorando cerca de 1,20 segundos para a transmissão de cada pacote. Acreditamos que as ineficiências possam ter sido devidas tanto ao mau contato dos componentes, como à ineficiência do código projetado.The construction of the co-simulated network (physical network and simulated network) of this thesis will be a basis for the development of simulation techniques using the OMNeT ++ (computational) platform with (physical) sensors. Once the platform is established, it would be possible to extend the operation of the network to other environments, such as the development of physical networks in mining. In this sense we can build a physical network, and simulate the behavior of other components and networks using OMNeT ++. As this work uses IoT for the development of the proposed topology, this work ends up corroborating the use of low power appliances. The objective of this dissertation is to show in a real environment the use of co-simulation with OMNeT ++ to validate the platform created for the production of simulations of IoT networks. In such a way it will be possible to show that the co-simulation works properly in the OMNeT ++ simulations environment, and to provide a basis for possible future expansions. Basically we have a set of components that will be connected to each other wirelessly (creating an RSSF), which will be connected (via TCP / IP) to a computer running OMNeT ++, which supports an IP network topology created inside the simulator. In this way a complete network of devices, both simulated and physical, is created and can be used to collect statistical results of its performance, namely within OMNeT ++. We had because of receiving packets on average 64.4%, taking about 1.20 seconds for the transmission of each packet. We believe that the inefficiencies may have been due to both the bad contact of the components and the inefficiency of the designed code

A modular co-simulation approach for urban energy systems

Cities are the main site of energy consumption, which result in approximately 71% of global CO2 emissions. Therefore, energy planning in cities can play a critical role in climate change mitigation by improving the efficiency of urban energy usage. The energy characteristics of cities are complex as they involve interactions of multiple domains, such as energy resources, distribution networks, storage and demands from various consumers. Such complexity makes urban energy planning a challenging task, which requires an accurate simulation of the interactions and flows between different urban energy subsystems. Co-simulation has been adopted by a number of researchers to simulate dynamic interactions between subsystems. However, the research has been domain specific and could only be used in limited areas. There was no generic approach to tackle the interoperability challenge of a comprehensive simulation for urban energy systems. To address such a gap, the aim of this thesis is to develop a generic and scalable urban energy co-simulation approach to comprehensively model the dynamic, complex and interactive nature of urban energy systems. This was achieved through the development of a generic and scalable urban energy co-simulation architecture and approach for the integration and orchestration of urban energy simulation tools, also called simulators, from different domains. Nine requirements were identified through a literature review of co-simulation, its approaches, standards, middleware and simulation tools. A conceptual co-simulation architecture was proposed that can address the requirements. The architecture has a modular design with four layers. The simulator layer wraps the simulation tools; the interconnection layer enables the communication between tools programmed in different programming languages; the interoperability layer provides a mechanism for the tool composition and orchestration; and the control layer controls the overall simulation sequence and how data is exchanged. Based on the architecture, a Co-simulation Platform for Ecological-urban (COPE) was developed. Suitable co-simulation software libraries were adopted and mapped together to fulfil the requirements of each layer of COPE to achieve the research objectives. For different simulation purposes, subsystem simulation tools from different domains could be selected and integrated into the platform. A master algorithm could then be developed to orchestrate and synchronise the tools by controlling how the tools are run and how data are exchanged among the tools. In order to evaluate COPE’s fundamental functionality and demonstrate its application, two case studies are presented in the thesis: simulating multiple application domains for a single building and multiple (interacting) buildings respectively. From the case studies, it was observed that COPE can successfully synchronise and manage interactions between the co-simulation platform and integrated simulation tools. The simulation results are validated by comparing the results obtained from the direct coupling approach. The applicability of COPE is demonstrated by simulating energy flows in urban energy systems in a neighbourhood context. Computing performance diagnostics also showed that this functionality is achieved with modest overhead. The layered modular co-simulation approach and COPE presented in this thesis provide a generic and scalable approach to simulating urban energy systems. It could be used for decision making to improve urban energy efficiency

Integrated modelling of control and adaptive building envelope: development of a modelling solution using a co-simulation approach

Adaptive building envelopes can dynamically adapt to environmental changes, often supported by a control system. Although adaptive building envelopes can play a significant role in improving thermal building performance, uncertainties and risks have led to a slow uptake in the built environment. A reason for this is the reluctance of practitioners to consider integrating adaptive building envelopes in building design. This may be due to Building Performance Simulation (BPS) tools that can be employed for performance prediction of design proposals with adaptive building envelopes. However, a shortcoming of existing tools is their limited adaptation that hinders proper modelling of the influence of control decisions on the dynamic behaviour of these building envelopes. This thesis investigates an approach for the integrated modelling of control and adaptive building envelope. To this aim, an interview-based industry study with experts in adaptive building envelope simulation was conducted. The interview study aimed to advance the understanding of the limitations of adaptive building envelope simulation in current design practice and to identify implications for future tool developments. The feedback from the interviewees was then used to inform the development of an integrated modelling approach using co-simulation, the accuracy and functionality of which were subsequently tested through a validation study and a multiple case study. The findings of the interview study outline the need for more flexible modelling approaches that enable designers to fully exploit adaptive building envelopes in building design. The proposed modelling approach for predicting the thermal performance of adaptive building envelopes has shown that its co-simulation setup seems to offer more flexibility in integrating the dynamic behaviour of adaptive building envelopes. What is now needed is to observe the execution of the modelling approach in design practice to obtain realistic feedback from its users and to verify that it works as intended

Testen von Datensicherheit in vernetzten und automatisierten Fahrzeugen durch virtuelle Steuergeräte

In der Automobilindustrie sind in den vergangenen Jahren die zwei Trends Automatisierung und Vernetzung entstanden. Diese Trends sorgen für eine steigende Anzahl an Funktionen im Fahrzeug. Neben einer Erhöhung des Komforts nehmen jedoch auch die Risiken durch den unerlaubten Zugriff von außen zu. Das IT-Manipulationen bei Fahrzeugen keine Ausnahme bilden, zeigen bereits erste Beispiele. Besonders durch die langen Lebenszyklen in der Automobilindustrie und der Tatsache, dass 44% aller Angriffe auf IT-Systeme durch bekannte Schwachstellen geschehen, müssen Fahrzeuge bereits in der Entwicklung abgesichert werden. Bezogen auf die funktionale Sicherheit (engl. Safety) existieren in der Automobilentwicklung bereits eine Vielzahl an Testprozessen und -methoden. Eine Übertragbarkeit dieser auf die Datensicherheit (engl. Security) ist jedoch nicht gegeben, wodurch neue Methoden am Entstehen sind. Daher wird eine Testmethode mittels virtuellen Steuergeräten vorstellt. Hierfür wird aufgezeigt, welche Beobachtungspunkte und Überwachungsfunktionen für die Tests der Datensicherheit gegeben sein müssen, wie sich daraus eine Testmethodik ableiten lässt und wie diese Testmethodik anschließend in die Automobilentwicklung eingebunden werden kann. Für die Testmethodik wurden die Bereiche Speicher-, Numerische-, Systematische-, Funktionale- und Anwendungsfehler identifiziert. Der Fokus wird dabei auf die ersten beiden Fehlerarten gelegt und daraus Kriterien für einen Test der Datensicherheit abgeleitet. Anhand der Kriterien werden Beobachtungspunkte in bestehenden Testsystemen analysiert und basierend auf einem virtuellen Steuergerät neue Beobachtungspunkte ergänzt. Hierbei werden nicht nur Schnittstellen des Steuergeräts berücksichtigt, sondern ebenfalls interne Zustände des steuernden Artefakts (ausgeführte Instruktionen, Variablen und Speicherbereiche) und des ausführenden Artefakts (Register, lokaler Busse und Recheneinheit). Eine Berücksichtigung der internen Zustände ist wichtig, da Speicherfehler und numerische Fehler nicht zwangsläufig an die Schnittstellen propagieren und dadurch in der Umwelt sichtbar sind. Anhand der Beobachtungspunkte in einem virtuellen Steuergerät wurde eine Gesamtsystemsimulation erstellt, die das Steuergerät mit Applikation, Prozessor und Peripherie simuliert. Eine Co-Simulation übernimmt die Erzeugung der Teststimuli. Durch die Beobachtungspunkte können Rückschlüsse auf das Verhalten und die Zustände innerhalb des Steuergeräts gezogen werden. Durch die zusätzlichen Beobachtungspunkte können Testmethoden wie Überwachung der Instruktionen und Register, Analyse der Eingaben, Markierung des genutzten Speichers und Analysemöglichkeiten der Codeabdeckung eingesetzt werden. Zusätzlich ergeben sich durch evolutionäre Verfahren die Möglichkeit der Maximierung des Variablen Wachstums und des Speicherzugriffs sowie die Minimierung des Abstands zwischen Heap und Stack. Um die Testmethoden in einem Entwicklungsprozess einsetzten zu können werden die Ergebnisse auf eine vernetzte Funktion (Adaptive Cruise Control) skaliert und das Echtzeitverhalten beurteilt. Für die Simulation eines einzelnen Steuergeräts können dabei bis zu 62 Steuergeräte parallel simuliert werden, bevor die Simulation auf der realen Hardware schneller als der Ablauf in der Simulation ist. Durch die Ergänzung von Überwachungsfunktionen und Co-Simulationen sinkt das Echtzeitverhältnis jedoch exponentiell. Abschließend wird die Testmethodik mit Angriffen aus der Automobilindustrie bewertet und aufgezeigt, welche Fehler erkannt worden wären. Die Testmethodik ist dabei jedoch nur so genau, wie die zugrundeliegenden Modelle. Eine Erhöhung der Genauigkeit bedeutet dabei höhere Kosten in der Entwicklung. Zudem muss der Quellcode für die Applikation als Source- oder Maschinencode bekannt sein. Wird die Testmethode als Ergänzung zu bereits bekannten Testverfahren eingesetzt, können jedoch Probleme in der Datensicherheit bereits der Entwicklung erkannt werden