Stability Analysis of Droop-Controlled Inverter-Based Power Grids via Timescale Separation

We consider the problem of stability analysis for distribution grids with droop-controlled inverters and dynamic distribution power lines. The inverters are modeled as voltage sources with controllable frequency and amplitude. This problem is very challenging for large networks as numerical simulations and detailed eigenvalue analysis are impactical. Motivated by the above limitations, we present in this paper a systematic and computationally efficient framework for stability analysis of inverter-based distribution grids. To design our framework, we use tools from singular perturbation and Lyapunov theories. Interestingly, we show that stability of the fast dynamics of the power grid depends only on the voltage droop gains of the inverters while, stability of the slow dynamics, depends on both voltage and frequency droop gains. Finally, by leveraging these timescale separation properties, we derive sufficient conditions on the frequency and voltage droop gains of the inverters that warrant stability of the full system. We illustrate our theoretical results through a numerical example on the IEEE 13-bus distribution grid

Smart energy cities: the evolution of the city-energy-sustainability nexus

This paper reviews the emergence and development of the “smart energy city” as an academic, normative, and applied concept. An examination of the academic literature since the early 2000s reveals the unfolding of spatiotemporal trends relating to this concept. It has been emerging to represent a sector-specified version of its sister concept of smart cities, also popularized in the past decade. However, the idea of the smart energy city has its own historic precursors and nationally specific trajectories. It rose from concerns with energy efficient/green buildings as well as smart grids for low carbon and distributed energy generation and distribution, which were later scaled up to the whole urban scale, and to embrace multiple other urban sectors and urban domains. By so doing, and combining the developments in ICT-led smart cities and sustainable energy, the notion of the smart energy city has come close to represent a digitally-mediated variant of low carbon cities. It can, thus, be conceptualized as a blend of smart cities and low carbon cities. National and urban case studies help to further distinguish “actually existing” projects, patterns, and conceptualization relating to both smart cities and smart energy cities and barriers to their practical integration. A greater focus on intersystem integration and a multistakeholder approach more recently offers a stronger representation of interdisciplinarity and conveys the complexity of the system involved, where humans and social systems become increasingly more central

Оптимізація технікоекономічних показників локальних систем електроживлення з транзактивним керуванням

У монографії розглянуті питання побудови та функціонування локальних систем електроживлення з транзактивним керуванням. Представлена оптимізація технікоекономічних показників. Розроблено алгоритм для оптимізації витрат, який виконує розрахунок розподілу потужностей паралельно з’єднаних генераторів, ці потужності відповідають мінімальному значенню витрат. Запропоновано забезпечення вимог щодо якості енергопостачання та електромагнітної сумісності в рамках транзактивного контролю, шляхом використання розроблених систем силової електроніки як інтерфейсу сонячних та вітрогенераторів. Розглянуті питання якості електричної енергії локальних систем, надійності та обмінних енергетичних процесів

Agents and Robots for Reliable Engineered Autonomy

This book contains the contributions of the Special Issue entitled "Agents and Robots for Reliable Engineered Autonomy". The Special Issue was based on the successful first edition of the "Workshop on Agents and Robots for reliable Engineered Autonomy" (AREA 2020), co-located with the 24th European Conference on Artificial Intelligence (ECAI 2020). The aim was to bring together researchers from autonomous agents, as well as software engineering and robotics communities, as combining knowledge from these three research areas may lead to innovative approaches that solve complex problems related to the verification and validation of autonomous robotic systems

The (long) road towards smart management and maintenance: Organising the digital transformation of critical infrastructures

The digital transformation of organisations, triggered by various digital technologies such as smart sensors, smart meters and IoT devices, provides large amounts of data that make it possible to make smarter decisions. For (Dutch) infrastructure organisations this provides opportunities to smarten the management and maintenance of their assets. But why are these technologies not used on a large scale yet? Two important hurdles for infrastructure managers here are 1) accessing the right data and the expertise needed to transform data into information and 2) the need to collaborate closely with partners in their respective supply networks. This doctoral thesis investigates these hurdles, thereby adding to the emerging literature regarding the impact of digital transformation on collaborating organisations and providing Dutch infrastructure with practical ways to overcome these hurdles. The three empirical studies in this doctoral thesis each investigate a specific aspect of the impact of digital transformations on collaborating supply network partners. Specifically, the study in Chapter 2 focuses on how the two main data processing activities (i.e. gathering data and transforming data) can be managed in dyadic relationships through contractual and relational governance mechanisms. The study in Chapter 3 focuses on how post formation adjustments to contractual and relational governance mechanisms in dyadic relationships are made to cope with uncertainty caused by the digitalisation of collaborative processes. Finally, the study in Chapter 4 focuses on the governance of supply networks (i.e. networks with three or more partners) and how these can be motivated to start sharing and using data coming from digital technologies