Improving Grid Hosting Capacity and Inertia Response with High Penetration of Renewable Generation

To achieve a more sustainable supply of electricity, utilizing renewable energy resources is a promising solution. However, the inclusion of intermittent renewable energy resources in electric power systems, if not appropriately managed and controlled, will raise a new set of technical challenges in both voltage and frequency control and jeopardizes the reliability and stability of the power system, as one of the most critical infrastructures in the today’s world. This dissertation aims to answer how to achieve high penetration of renewable generations in the entire power system without jeopardizing its security and reliability. First, we tackle the data insufficiency in testing new methods and concepts in renewable generation integration and develop a toolkit to generate any number of synthetic power grids feathering the same properties of real power grids. Next, we focus on small-scale PV systems as the most growing renewable generation in distribution networks and develop a detailed impact assessment framework to examine its impacts on the system and provide installation scheme recommendations to improve the hosting capacity of PV systems in the distribution networks. Following, we examine smart homes with rooftop PV systems and propose a new demand side management algorithm to make the best use of distributed renewable energy. Finally, the findings in the aforementioned three parts have been incorporated to solve the challenge of inertia response and hosting capacity of renewables in transmission network

Assessing frequency support and voltage regulation by wind turbines: scalability and replicability analysis of the OSMOSE project

Questa tesi di laurea ha avuto come obiettivo quello di condurre una analisi di scalabilità e replicabilità all’interno di un progetto Europeo relativo alle smart grid. Nel dettaglio, ci si è concentrati sui risultati raggiunti da due impianti eolici pilota che hanno implementato la fornitura di inerzia sintetica e la regolazione automatica della tensione. Da una analisi di scalabilità e replicabilità, ci si aspetta di ottenere sia indicazioni assolute sulle performance delle soluzioni implementate sia, soprattutto, indicazioni su quelle che potrebbero essere le principali barriere e difficoltà nell’implementare le medesime funzioni su differente scala o con differenti condizioni al contorno. Perciò, si sono impostate due diverse tipologie di analisi: una di tipo qualitativo, che ha direttamente coinvolto i partner del progetto con lo scopo di investigare sulla tecnologia utilizzata, e una seconda analisi quantitativa, che si è svincolata dagli aspetti tecnologici dei singoli impianti e quindi ha analizzato la disponibilità e gli impatti che i nuovi servizi di regolazione avrebbero sull’intera penisola italiana. La prima analisi ha permesso di comprendere potenzialità e barriere delle singole implementazioni. La seconda invece, si è resa necessaria per stimare i risultati che potrebbero essere ottenuti estendendo le funzioni innovative a tutti gli impianti esistenti sul territorio, tenendo conto che nella fornitura di servizi basata su fonte eolica è fondamentale considerare la variabilità e arbitrarietà caratteristica del vento.This thesis aimed to conduct a scalability and replicability analysis within a European smart grid project. In detail, the focus was on the results achieved by two pilot wind farms that implemented the provision of synthetic inertia and automatic voltage control. From a scalability and replicability analysis, it is expected to obtain both absolute information on the performance of the implemented solutions and information on what might be the main barriers and difficulties in implementing the same functions on a different scale or with different boundary conditions. Therefore, two different types of analysis were set up: a qualitative one, which directly involved the project partners with the aim of investigating the technology used, and a second quantitative analysis, which analysed the functional aspects of the implemented solutions by assessing the availability and impacts that the new regulatory services would have on the entire national perimeter. The first analysis allowed to understand the strengths and barriers of each implementation. The second analysis, on the other hand, was necessary to estimate the results that could be obtained by extending the innovative functions to all existing plants in the area, bearing in mind that in the provision of services based on wind power it is essential to consider the variability and arbitrariness characteristic of wind

Agilicious: Open-source and open-hardware agile quadrotor for vision-based flight

Autonomous, agile quadrotor flight raises fundamental challenges for robotics research in terms of perception, planning, learning, and control. A versatile and standardized platform is needed to accelerate research and let practitioners focus on the core problems. To this end, we present Agilicious, a codesigned hardware and software framework tailored to autonomous, agile quadrotor flight. It is completely open source and open hardware and supports both model-based and neural network–based controllers. Also, it provides high thrust-to-weight and torque-to-inertia ratios for agility, onboard vision sensors, graphics processing unit (GPU)–accelerated compute hardware for real-time perception and neural network inference, a real-time flight controller, and a versatile software stack. In contrast to existing frameworks, Agilicious offers a unique combination of flexible software stack and high-performance hardware. We compare Agilicious with prior works and demonstrate it on different agile tasks, using both model-based and neural network–based controllers. Our demonstrators include trajectory tracking at up to 5g and 70 kilometers per hour in a motion capture system, and vision-based acrobatic flight and obstacle avoidance in both structured and unstructured environments using solely onboard perception. Last, we demonstrate its use for hardware-in-the-loop simulation in virtual reality environments. Because of its versatility, we believe that Agilicious supports the next generation of scientific and industrial quadrotor research

Exploiting phasor measurement units for enhanced transmission network operation and control

This thesis was submitted for the degree of Doctor of Engineering and awarded by Brunel UniversityIn order to achieve binding Government targets towards the decarbonisation of the electricity network, the GB power system is undergoing an unprecedented amount of change. A series of new technologies designed to integrate massive volumes of renewable generation, predominantly in the form of offshore wind, asynchronously connecting to the periphery of the transmission system, are transforming the requirements of the network. This displacement of traditional thermal generation is leading to a significant reduction in system inertia, thus making the task of system operation more challenging. It is therefore deemed necessary to develop tools and technologies that provide far greater insight into the state of the power system in real-time and give rise to methods for improving offline modelling practices through an enhanced understanding of the systems performance. To that extent PMUs are seen as one of the key enablers of the Smart Grid, providing accurate time-synchronised measurements on the state of the power system, allowing the true dynamics of the power system to be captured and analysed. This thesis provides an analysis of the existing PMU deployment on the GB transmission system with a view to the future system monitoring requirements. A critical evaluation and comparison is also provided on the suitability of a University based Low Voltage PMU network to further enhance the visibility of the GB system. In addition a novel event detection algorithm based on Detrended Fluctuation Analysis is developed and demonstrated, designed to determine the exact start time of a transmission event, as well as the suitability of such an event for additional transmission system analysis, namely inertia estimation. Finally, a reliable method for the estimation of total system inertia is proposed that includes an estimate of the contribution from residual sources, of which there is currently no visibility. The proposed method identifies the importance of regional inertia and its impact to the operation of the GB transmission system.Engineering and Physical Sciences Research Council (EPSRC) and National Grid