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The purpose of the paper is to introduce a new bi-directional approach to assess the gap between the customer needs and technology developers’ perception on the value propositions of innovations which includes storages. The paper used two methods, the first comprehensive sense and respond analysis investigated technology developers’ perceptions using the value propositions defined under the EU-funded H2020 RESOLVD project. The second method focused on customers and collected a survey which covered challenges, value propositions and preparedness to adopt new technology. The H2020 RESOLVD project has developed an intelligent low-voltage grid management system with storage. The results from the sense and respond analysis showed that most of the value propositions aligned with the responses from the broader survey which are needed within five years (e.g., improved power quality of grid, fault detection, reduced technical loss). However, the cybersecurity perception differed between developers and distribution system operators (DSOs). The customer survey highlighted that certain value propositions of technological solutions are needed more urgently than others, and therefore, technology developers should prioritize these in further developments. Regarding the use of flexibility to manage the LV grid, unclear regulations were expressed as a key barrier, thereby affecting business feasibility around battery storage.

The application of Artificial Intelligence techniques in industry equips companies with new essential tools to improve their principal processes. This is especially true for energy companies, as they have the opportunity, thanks to the modernization of their installations, to exploit a large amount of data with smart algorithms. In this work we explore the possibilities that exist in the implementation of Machine-Learning techniques for the detection of Non-Technical Losses in customers. The analysis is based on the work done in collaboration with an international energy distribution company. We report on how the success in detecting Non-Technical Losses can help the company to better control the energy provided to their customers, avoiding a misuse and hence improving the sustainability of the service that the company provides.

Microgrid integration and fault protection in complex network scenarios is a coming challenge to be faced with new strategies and solutions. In this context of increasing complexity, this paper describes two specific overload control strategies for four-wire inverters integrated in low voltage four-wire alternating current (AC) microgrids. The control of grid-tied microgrid inverters has been widely studied in the past and mainly focused on the use of droop control, which hugely constrains the time response during grid-disconnected operation. Taking into account the previous knowledge and experience about this subject, the main contribution of these two proposals regards providing fault current limitation in both operation modes, over-load capability skills in grid-connected operation and sinusoidal short-circuit proof in grid-disconnected operation. In the complex operation scenarios mentioned above, a hybrid combination of AC droop control based on dynamic phasors with varying virtual resistance, and voltage/frequency master voltage control for grid-(dis)connected operation modes are adopted as the mechanism to enhance time response. The two proposals described in the present document are validated by means of simulations using Matlab/Simulink and real experimental results obtained from CENER (The National Renewable Energy Centre) experimental ATENEA four-wire AC microgrid, obtaining time responses in the order of two-three grid cycles for all cases.

In this paper, the finite control set model predictive control is combined with the vector operation technique to be applied in the control of a three-phase active power filter. Typically, in the finite control set technique applied to three-phase power converters, eight different vectors are considered in order to obtain the optimum control signal by minimizing a cost function. On the other hand, the vector operation technique is based on dividing the grid voltage period into six different regions. The main advantage of combining both techniques is that for each region the number of possible voltage vectors to be considered can be reduced to a half, thus reducing the computational load employed by the control algorithm. Besides, in each region, only two phase-legs are switching at high frequency while the remaining phase-leg is maintained to a constant dc-voltage value during this interval. Accordingly, a reduction of the switching losses is obtained. Unlike the typical model predictive control methods which make use of the discrete differential equations of the converter, this method considers a Kalman filter in order to improve the behavior of the closed-loop system in noisy environments. Selected experimental results are exposed in order the demonstrate the validity of the control proposal.

Power devices intended for high-voltage systems must be tested according to international standards, which includes the short-time withstand current test and peak withstand current test. However, these tests require very special facilities which consume huge amounts of electrical power. Therefore, mathematical tools to simulate such tests are highly appealing since they allow reproducing the electromagnetic and thermal behavior of the test object in a fast and economical manner. In this paper, a three-dimensional finite element method (3D-FEM) approach to simulate the transient thermal behavior of substation connectors is presented and validated against experimental data. To this end, a multiphysics 3D-FEM method is proposed, which considers both the connector and the reference power conductors. The transient and steady-state temperature profiles of both the conductors and connector provided by the 3D-FEM method prove its suitability and accuracy as compared to experimental data provided by short-circuit tests conducted in two high-current laboratories. The proposed simulation tool, which was proven to be accurate and realistic, may be particularly useful during the design and optimization phases of substation connectors since it allows anticipating the results of mandatory laboratory tests.