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Emerging appliance technology deployed by more and more energy-aware citizens requires an in-depth analysis of the actual/real load profiles for residential consumers. While the smart metering roll-out makes this analysis possible, especially when using the new generation smart meters with enhanced functionalities and high reporting rates, its necessity is highlighted by the different, asynchronous and sometimes unpredictable consumer behavior especially when dealing with young educated adults. In this context, a correlation-based analysis of consumer behavior and its impact on voltage levels is proposed in this paper. High reporting rate smart meters installed in a student campus are used as pilot for this study.

Over the last decades, the study of the asymmetrical power flow in distribution systems has come to play a crucial role. That is because of the increased number of asymmetrical loads given the high penetration of distributed generation within these distribution networks. Thus, the goal of this paper is to conduct a comparison of the voltage profiles and power losses in a grid based on the IEEE 34 bus topology, over 24 h, when an SVC (Static Var Compensator) and a shunt are connected to a node where a student residence is also connected.

As part of the global interest towards energy efficiency and low carbon emissions, an increased interest in electric energy consumption for end-users can be observed. Part of these initiatives concentrate on balancing the difference between generation and load curves and others on the study of human behavior and the possibility of engaging the end-user itself in this effort. In the same time, these studies highlight the difference between the theoretical load curves based on statistical information and used in planning activities and actual load curves of different types of users (e.g.: young professionals, families in large cities). In this context, the paper presents evidence of this difference based on a study performed for Politehnica University of Bucharest students. Some different aspects will be discussed: (1) students’ perception regarding their own consumption, (2) measured load curves for university dorms (3) the difference between these and classical load curves. The chosen sample, students living in a university campus is representative for future lead users in smart cities. Even more, this is the generation that needs to be aware of the residential consumption impact on the electric grid and to be involved in the effort to create sustainable local energy communities.

In the context of emerging technologies and increased consumer awareness, device interoperability and portability is becoming one of the most important features in today’s market. A study based on the level of interoperability as defined in the SGAM for commercially available smart meters is conducted in this paper. The findings focus on available information for the communication layer of smart meters and propose a set of interoperability levels based on communication performances and dynamic behaviour.

The scope of this paper is to present an EU-28 overview of the smart meter roll-out implementation progress. The study is based on publicly available information and presents a traffic light map with the deployment status by mid-2017. A series of particular cases are approached and a gap between the European Commission recommendation, expected diffusion rate and actual deployment is identified. The study further provides some possible causes considering the number of metering points available at EU-28 level, country specific assumed targets and macro-environmental factors.

Over the last years, the PV systems have become a very attractive solution in view of achieving sustainability and efficient local generation with applicability for university campuses. However, such grids exhibit high load variation spanning from low (during vacation) to high (during winter semesters, for example). Thus, the voltage regulation in low voltage grids becomes important. The purpose of this work is to present five control strategies for voltage regulation based either on using electricity storage, transformer tap changing or on a combination of both.

The scope of this paper is to present an EU-28 overview of the smart meter roll-out implementation progress. The study is based on publicly available information and presents a traffic light map with the deployment status by mid-2017. A series of particular cases are approached and a gap between the European Commission recommendation, expected diffusion rate and actual deployment is identified. The study further provides some possible causes considering the number of metering points available at EU-28 level, country specific assumed targets and macro-environmental factors.

The Holy Bible includes descriptions of the spine with both neurosurgical and neurological implications and most spinal disorders presented have been briefly described and display a mystical nature. The Holy Bible is a book full of sacred precepts and not a medical encyclopedia as it was written in the context of that age, and in a language that had to be understood by people of that era. This paper aims to give a short presentation of several diseases of the spine mentioned in the Holy Scripture in order to identify the most common disease among the Jews during biblical times and attempts to provide their diagnosis.

This paper deals with a comparative analysis carried out on two types of PV panels widely spread on the market: polycrystalline and thin-film (CIS technology). The research was focused on the performance evaluation of the studied PV panels in real operation conditions. In this context the influence of different parameters (temperature, solar irradiance and shadowing effect) on panels' performance were studied.

A special category that requires special attention and has become a pressing issue in psychopedagogy is that of children under a form of social protection. The present study, conducted in orphanages in the Arges County, tries to analyze the school success/failure of these children/young people and at the same time to identify the cultural, family and educational barriers that lead to issues related to integration, socialization and even finding a job. The analysis of the theme was based on issues of qualitative research, the research methods being document analysis and the interview. The results of this study demonstrate that solving the problems in question requires individualized treatment, non-formal education, vocational counseling and even therapies. The risk of failure of the child is not limited to academic failure. Therefore a sustained effort of both the General Directorate of Social Assistance and Child Protection, the school and the community is needed to increase the school performance of institutionalized children and at the same time to achieve adequate social integration.

The climate changes are becoming more and more obvious for each of us. Nowadays, the link between the greenhouse gas (GHG) emissions and the climate change is a worldwide recognized phenomenon. Although, the consumption of grid electricity is one of the most important sources of GHG emissions, the effects of this human behavior on the environment are still unknown, being invisible to the domestic consumer. A universal solution for the consumer information, from the environmental impact viewpoint of its electricity consumption behavior, may come from the smart metering area. A smart meter could also provide information about the carbon footprint. This paper presents a carbon footprint computation and possible displaying algorithm associated with the household consumption of grid electricity. The algorithm could be implemented in the smart metering system and it represents an easy user-intuitive way to improve the domestic consumer information using the smart meter data. Results based on typical load curves and national energy mix are presented.

This paper presents a Robotics laboratory conceived for the Electrical Engineering students. The laboratory work comprises two stages - a preliminary one, in which they apply Robotics concepts by means of ready to use platforms, and a second one, when the students are engaged in a complex project, whose goal is to develop their own platform. There are detailed the work stages, emphasizing both the trainer and the students' activities.

Storage selection is usually based on availability and price but there is always a need to assess the opportunity of making use of existing storage facilities versus commissioning new installations or use of other customer-premises related technologies due to the fact that some constrains are increasing the overall costs of electrical storage-based solutions. In this paper, a comprehensive set of characteristics of storage facilities, able to accurately describe their use was implemented in an updatable database and its functionality was tested using a study case and Cost Benefit Analysis (CBA) considerations. The database together with the storage selection procedure is dedicated to help Distribution System Operators (DSOs) in their decision to implement storage technologies at substation level.

Introduction: Spinal teratoma is an extremely rare entity as it represents 0.10-0.60% of all spinal tumors. It is mainly diagnosed during the first two decades of life and can be associated with spinal dysraphism. Aim: To present a case of an asymptomatic mature teratoma of filum terminale, incidentally diagnosed in an elderly patient admitted to the Neurosurgery Department for multiple traumas after falling from 3 meters height. Case description: A 76 year-old patient was admitted in the 2nd Neurosurgery Department, “Prof. Dr. N. Oblu” Emergency Clinical Hospital, Iasi with multiple traumas after falling from 3 meters height. The patient presented bilateral paresthesia of lower limbs and urinary incontinence. Radiography of the dorsal-lumbar spine column in emergency highlighted a dorsal - lumbar fracture (D12-L1) with medullar compression. MRI examination revealed a neoformation of filum terminale that filled almost the entire spinal canal, which had a composite, fatty and fluid structure, corresponding to L2-L4 and compressing the medullary cone. The neurosurgical decision was the excision of the entire neoformation. The histopathological examination of excised pieces revealed the presence of adipose tissue mixed together with striated and smooth muscle fibers, small and large cysts lined by various epithelia ranging from malpighian keratinized multilayered to simple ciliated columnar epithelium. No immature or malignant cells were identified and therefore the diagnosis was mature teratoma of filum terminale. The evolution of the patient was favorable with the remission of the neurological deficit. Conclusions: Our patient is one of the oldest patients diagnosed up to date with a mature teratoma of filum terminale. Moreover, the location of neoformation at the lumbar (L2-L4) level is extremely rare. This case also highlights the fact that this mature teratoma was discovered by chance, when the patient came to the Neurosurgery Department for a spinal injury due to a falling from a tree.

Deposition of bioactive coatings composed of zinc oxide, cyclodextrin and cefepime (ZnO/CD/Cfp) was performed by the Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. The obtained nanostructures were characterized by X-ray diffraction, IR microscopy and scanning electron microscopy. The efficient release of cefepime was correlated with an increased anti-biofilm activity of ZnO/CD/Cfp composites. In vitro and in vivo tests have revealed a good biocompatibility of ZnO/CD/Cfp coatings, which recommend them as competitive candidates for the development of antimicrobial surfaces with biomedical applications. The release of the fourth generation cephalosporin Cfp in a biologically active form from the ZnO matrix could help preventing the bacterial adhesion and the subsequent colonization and biofilm development on various surfaces, and thus decreasing the risk of biofilm-related infections., Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI; European Union (EU)

Recently the main IEC standard on measurements in the frame of power quality has been updated [1], and a new section has been added for rapid voltage changes [RVC] assessment. Also, in the standard it is acknowledged the variability of voltage signals and the need of validation of the “steady state” behavior of the system characterizing the measurement context. In this context it is proposed the 1s time interval within the voltage variability should relate to the dynamic behavior. This paper addresses the potential implications of the new standard on the measurement layer in LV grids and on the knowledge management process for various power systems applications. PMU data obtained with the highest reporting rate is used to identify a rapid voltage change event and to potentially discriminate it from voltage sags or swells.

In this paper, experimental results obtained with two different types of measurement equipment are presented comparatively. One type of equipment is dedicated to power quality monitoring, while the second one is a phasor measurement unit with a supplementary module intended to be used to determine some power quality parameters. Experiments were designed as to emulate different power quality levels in LV office typical networks, in what concerns unbalance and harmonic distortion of voltage and current waveforms. All results have been compared with a focus on the rms values of the currents measured by the two types of equipment. Data from the phasor measurement unit were aggregated before this comparison was made in order to mitigate the potential inadvertences introduced by the different reporting rates of the two devices. Special attention has been paid to frequency measurement as well, considering its importance in emerging grids.

Data received with high reporting rates and aggregated data from measurement equipment (i.e. with lower reporting rates and usually complying with power quality time-aggregation standards) are sometimes used in the same application. This is raising the question of merging the two types of information and assessing the quality of the result. Modern control algorithms process information acquired from distributed, synchronized measurement systems. Their requirements are difficult to meet when multiple measurement approaches are simultaneously used: on one side, the existing time-aggregation assessments in SCADA framework, including smart meters; on the other side, the high-resolution waveform-based monitoring devices like PMUs with fault-recorder functionality which are increasingly deployed in distribution systems. In this paper we propose a methodology for assessing the variability of a particular quantity in the monitored power network while using two different reporting rates and time-aggregation algorithms.

In Romania, the communist period brought about some serious damage to the image of the woman both at the society and at the family level, a fact that generated numerous social problems. Later on, the transition from socialism to capitalism was carried out with difficulty, and, in order to overcome the crisis situation (both social and familial) created, after 1989 the politicians preferred to “import” solutions without adapting them to the needs of the people, to its lifestyle and especially to the religion and culture of this nation. Moreover, domestic violence “continued its natural course”, still being considered a hidden problem, protected by the privacy of the family, by the institution of marriage and conceived as a thing that was allowed, accepted. Studies that should analyse the real status of this social problem were carried out only at national level, with more emphasis being laid on identifying the cases reported and solved and on the types of violence the victims were subjected to, but, unfortunately, the local or regional studies that should bring new and specific elements are very few. For this reason, the present survey tries to analyse the issues related to woman’s victimisation within an area lying in the south of Romania, namely in the Argeş County, by shaping a portrait of the woman from this area who presents a high risk of being abused and by identifying the cultural and structural barriers that prevent abuse and provide the means the victims need in order to be safe. The interviews carried out with the victims of domestic violence, as well as the analysis of their files, for a period of three years, render, in addition to the severity of the acts of violence and the trauma suffered, the authorities’ incapacity to manage this phenomenon which seems to become more and more present in Romanian households every single day that goes by. En Rumania, el periodo bajo el régimen comunista afectó seriamente la imagen de la mujer en la sociedad pero también en la familia, lo que generó varios problemas sociales. Más tarde, la transición desde el socialismo al capitalismo se realizó con dificultad y para enfrentar la situación de crisis (bien social y bien familiar) creada, después del año 1989, los políticos prefirieron «importar» soluciones sin adaptarlas a las necesidades del pueblo, a su estilo de vida pero sobre todo a la religión y cultura de esta nación. Además, la violencia doméstica «siguió su curso normal» todavía considerándose un problema ignorado, protegido en la intimidad de la familia, por la institución del matrimonio y visto como una cosa permitida, aceptada. Los estudios que analizan la situación real de este problema social se realizaron solamente al nivel nacional centrándose más en identificar los casos denunciados, solucionados y los tipos de violencia a las cuales fueron sujetas las víctimas, pero desgraciadamente, hay muy pocos estudios locales o regionales que traten de traer elementos nuevos y específicos. Por lo tanto, este estudio trata de analizar los problemas relacionados a la victimización de la mujer en una zona del Sur de Rumania, concretamente, en la provincia de Argeş, esbozando un retrato de la mujer que vive en esta zona y que presenta un riesgo más alto para abuso e identificando las barreras culturales y estructurales que impiden el abuso y ofrecen la ayuda que necesitan las víctimas para sentirse seguras. Las entrevistas realizadas con las víctimas de la violencia doméstica así como el análisis de los expedientes correspondientes, por un periodo de tres años, ponen de manifiesto, aparte de la gravedad de los actos de violencia y de los traumas sufridos, la incapacidad de las autoridades de gestionar este fenómeno que parece extenderse más en los hogares de los rumanos.

Conjunctival malignant melanoma is a rare tumor with a high risk of local recurrence, lymph node and systemic metastases. The aim of this study was to correlate tumor thickness, tumor ulceration, high mitotic rate, epithelioid cells with the presence of metastases and death from conjunctival malignant melanoma. We report the case of a 33-year-old patient who presented with a left eyelid ptosis associated with an eyelid prominence, foreign body sensation in the eye, and bloody discharge, symptoms occurring about one month earlier. Ophthalmologic examination revealed in eyelid conjunctiva two vegetant and ulcerative tumors of 8/6 mm and 3/3 mm. The two tumors were surgically removed with safety margins. The diagnosis of amelanotic malignant melanoma of the conjunctiva with brain metastasis was made by routine morphological methods and immunohistochemical reactions (HMB45, vimentin, S100 protein). Systemic metastases (skin, brain, lung, liver, kidney, peritoneal) and peripancreatic lymph node metastases were detected at 1.9 years after the diagnosis of conjunctival malignant melanoma. The patient died three months after the surgical excision of brain metastasis. Early diagnosis is essential to prevent tumor recurrence, ocular invasion, systemic and lymph node metastases, and preserving visual function.

The emergence of next generation WAMS and WAMPAC networks offers promising advantages for ensuring the stability of the distribution grid. Thanks to the revolutionary synchrophasor technology, the power system observability is no longer an unknown quantity. However the deployment of such systems is heavy and rigid. We implemented a mobility-oriented lightweight deployment consisting in several PMUs and a couple of PDCs for monitoring certain segments of active distribution grids, which can be moved across geographic regions with ease and, at the same time, can be reconfigured and adjusted to integrate easily to any existing network topology. This paper presents the challenges involved by this new mobility approach, the structure of our existing flexible deployment and the results we have achieved in one of the active grid segments where we have recently performed an on-field installation of the whole deployment scheme.

Smart Grids is already considered an attractive topic in the power engineering education programs. Politehnica University of Bucharest has a unique profile in the engineering higher education landscape by including among its 14 Faculties, one dedicated to Power Engineering and another one to Electrical Engineering. In this paper we focus on the smart grids topics that the students enrolled in non-power engineering programs are exposed to. We believe that these courses reflect in a high degree the smart grids philosophy, seen as a mix of communication, power transfer and information processing layers. In this paper, several courses outlines are presented as an example of developing the missing link between equipment providers and the grid stakeholders (customers, network operators and energy providers).

The need of using in the same application synchronized data received with high reporting rate (like those provided by Phasor Measurement Units, PMUs) and aggregated data from measurement equipment with a lower reporting rate (which are usually complying with power quality data aggregation standards) is raising the question of achieving compatible data for ultimately assessing relevant information on the energy transfer in distribution grids. Moreover, modern control algorithms need to process information acquired from distributed, synchronized measurement systems, and embedded in data streams with high degree of correlation. The control requirements represent a true challenge in case when multiple measurement approaches are used: on one side, the existing time-aggregation based measurements are offered by currently deployed IEDs (SCADA framework), including smart meters and other merging units while on the other side, the high-resolution waveform-based monitoring devices like PMUs with fault-recorder functionality are increasingly deployed in distribution systems as well. In this paper is introduced a methodology for deriving an equivalent “accuracy class” of the measurement channel where the individual measurement device has associated a defined measurement quality and embeds specified aggregation algorithms.

The smart grids paradigm includes newly defined real time control strategies, and therefore detailed models for the energy transfer are required together with new algorithms for information retrieval. Although today measurement infrastructure (including the high reporting rate measurement devices, like Phasor Measurement Units) is capable to give insight to such details, the measurement information has to be structured in a new way. Moreover, new quantities - like rate of change of frequency - rocof - become relevant for both monitoring and control purposes. Presently there are in use aggregation algorithms inherited from power quality standards like the IEC 61000-4-30 set, but no algorithm is yet specified for rocof reporting. In this paper is presented a discussion of the time- and space- aggregation of frequency (including its rate of change) using phasor data concentrators' framework.

Hydatid cyst is a major public health problem in the pediatric population, both in terms of its frequency and of its endemic character in certain regions. The aim of the study was to present the incidence of hydatidosis in children who were hospitalized in pediatric clinics specialized in surgery of the Emergency Hospital for Children "St. Maria" from lasi.Prospective study conducted in the interval 2008-2012 in a series of 194 children patients from Moldova, Romania.The peak incidence of the hydatid disease is located around the age of 11-14 years (33%) in male patients (55%) from rural areas (79%) and families with low socioeconomic level. The hepatic localization of the hydatid cyst (50.51%) among children was more common than pulmonary localization (16.49%). Liver and lung localization was found in 22.16% of cases.Hydatidosis remains a major health problem requiring drastic measures to limit the spread and transmission of the parasite in humans, primarily by reducing the number of stray dogs.

In the case of electrical power networks using the RMS values for the measured voltages in order to determine its state is the accepted procedure. This method is based on the stationarity hypothesis. In this paper the validity of this hypothesis is studied based on numerical and experimental data. Practical examples of its non-validity are shown using the data aggregation algorithm.

One component of active power filters is the controller, whose design can determine the overall performance of the filter. Among different active filters control strategies, there is one configuration with generally accepted good performance: the harmonic controller. Its robustness against the measurements is evaluated in this paper for two different implementations. The overall performance of the control section of the active filter is analyzed taking into account the current and voltage measurement uncertainties For comparison purposes, the classical PI controller is also analyzed. Based on numerical simulation data, it is concluded that for similar active filter design, the control method based on harmonic controllers implemented on the synchronous referential is more appropriate.

As an alternative form of childcare, in Romania foster care is a welfare system that comes to meet the needs of the children who are medically fragile, who have been mistreated or who need specialized services. Most children who benefit from this protection have been traumatized and need medical, psychiatric, educational and special social care, and others come here because their biological families are unable or unequipped to manage care for a child with serious emotional issues or behavioral problems. The placement treatment is based on the premise that foster parents can serve as an important provider of therapy in the daily interactions with the child, that therapy should not be practiced only by a clinician and that the psychological needs of children can be best achieved in a family environment. Therefore, success of the placement to a specialist carer depends on the attachment that is created between the family of the carer and the child taken into care but also on the support received by the family from the community. The aim of this study is to find out the quality of life of children placed in a foster family. The standard of living is further understood as satisfaction of the basic needs (both spiritual and existential) of a child.The analysis of the problem was based on a qualitative research firstly using observation as a method precursory of all the other tools and direct investigation of the face-to-face type. The sample consisted of two groups of respondents - children and foster parents. It should be stressed that the investigation into family life is very difficult because it may interfere with intimacy. In the case of the questionnaire prepared for children, it was necessary for it to be made as simple as possible without going too deep into their privacy. The relatively simple and comprehensive questionnaire makes it easy to assess the quality of life of children placed in foster families and the fact that the issue is studied from two perspectives, using two different questionnaires provides the possibility to collect more varied information, at least some of which can be compared. The results of this study demonstrate that the placement of children in professional foster care increases their quality of life, bringing major contributions to their recovery and social integration. Keywords : social protection, foster family, quality of life, research method

Performance of active power filters is a function not only of the inverter design but also of the type of controller. Among different active filters control strategies, there are two different controller configurations with generally accepted good performance: the classical PI controller and the harmonic controller. Their robustness against the measurements is evaluated in this paper, while both are implemented in (d, q) frame. The influence of measurement uncertainties in the current and voltage measurement chain on the overall performance of the control part of the active filter is considered. Based on numerical simulation data, it is concluded that the method based on harmonic controllers implemented on the synchronous referential is more appropriate for the control of active filters.

As the distribution grids are an important part of the electrical system, their components need to be known in order to achieve optimal control of energy transfer. The present paper considers one component of the distribution grid namely the power line, aerial or cable, its model parameters leading to pseudo measurement uncertainties that can propagate through the entire grid when, for example, state estimation algorithms are applied. The paper discusses the case of short lines in order to decide whether it is important to have a better knowledge on the power lines parameters in estimating the losses of the electrical power system and also for various control strategies in active distribution grids. The validation of estimated parameters is made considering different load conditions for the aerial distribution line.

Active filters represent one of the most performant solutions for improving power quality in distribution networks. The development of active distribution grids imposed new requirements for active filters, as they are installed in points of common coupling (PCC) and considering that the grid parameters can change in time. In the paper a thoroughly approach of the measurement chain and associated uncertainties is going to be presented, together with a set of recommendations for a more robust design.

In this paper is presented a solution for optimal operation of the Francis turbine, the most used hydro energy converter in small hydro plants. As the efficiency of this turbine is highly dependent from the water flow, which generally has a large variation, variable speed operation was chosen. Due to the fact that all hydro generators are AC machines, the connection to the 50 Hz power grid can be done only using as interface the AC/DC DC/AC static converters. For higher than 1 MW power generators, front end three level inverters are recommended. In addition, for higher than 1 kV voltage, double three level inverters shall be used, as these are allowing their connection directly to the medium voltage grid, eliminating in this way the need of separation transformers. The converter control is done by a single chip DSP controller TM3202028, which takes care of all system functions.

The paper presents a variable speed solution for optimal operation of a group of small water turbines integrated in a medium voltage AC grid. As the efficiency of hydro machines is dependent on the water flow, which usually exhibits a large variation, operation at variable speed is considered. Due to the fact that all hydro generators are AC machines, the connection to the 50 Hz power grid can be done using an AC/DC-DC/AC interface. This power electronics-based interface, additional to transferring the energy from the generator to the grid, will also operate as a reactive power and a harmonic voltage compensator. A small AC micro grid was designed, comprising an 45 kW Frances turbo group, an 7 kW diesel synchronous generator, an 1.2 kW Ballard fuel cell, an 1.5 PV solar panel, an 3 kW energy storage acid lead battery and various loads.

A DC grid with different type of generators and load is presented. It is considered an islanded and grid connected operation. A low voltage laboratory model is simulated and tested and is expected in the future the results to be extended to high voltage applications. It is demonstrated that the solution can have not only scientific but also commercial viability.

Low power factor and increased current harmonic content are some of the negative effects of static power converters usage. To correct these disadvantages, active power filters with complex current control schemes can be used. This paper proposes an new method for tuning the resonant controllers also known as proportional sinusoidal-signal-integrator (P-SSI) controllers, based on Naslin polynomials theory.

The exploitation of renewable sources is expected to become the most promising solution to the environmental issues and to the permanent increase of prices of the fossil energy. Since most of renewable energy sources are widely distributed and the energy converters generally do not provide electric power at main grid frequency and voltage, a DC bus is suggested to be used for integrating them into a DC grid and further transfer it into an AC grid (usually available at a certain distance). Due to differences among the technical parameters of the power supply equipment, their outputs have to be firstly conditioned and then connected in parallel to a DC bus via appropriate power electronics. The aim of this paper is to suggest practical solutions for RES integration into distribution networks. The proposed DC link is simulated and different methods for load sharing and droop control is discussed. The standard model is a 6 kV, 1 MW electrical hydro generator with six phases YDelta connected, and having the output rectified by six phase diodes and paralleled to a 10 kV DC cable underground line. Three levels DC-AC, front-end bi-directional converters are used as interface with the AC grid. The connection of the low voltage grid (connecting the output of different power sources) to the medium voltage DC link is done by means of a DC-DC quasi-resonant converter provided with an internal high frequency insulation transformer. For the further connection of the DC link to the medium voltage AC distribution grid a solution employing IGBT four legs, front-end converter is proposed. A low voltage DC grid model, in the tens of kW range, 400/230 V AC - 720/320 V DC is under commissioning

The emergence of concepts, policies and applications like smart grid, energy communities, carbon footprint reduction, energy-efficient consumption, demand response, demand side management enables the development and implementation of algorithms and procedures dedicated to the analysis of domestic energy consumption. In this paper a method of modelling and forecasting is presented and an optimization of electric energy consumption using machine learning and a cost function based on local peaks identified in load curves is proposed. This approach supports the effort of balancing the difference between generation and consumption curves by enabling the DSO to identify peak intervals and routes towards optimization.

The article presents the most relevant aspects concerning an innovative European project in the field of electricity – „inteGRIDy” and its Romanian component „Ploiești Pilot”. Different sections of the paper describe the scope and objectives of the „inteGRIDy” project, significant aspects concerning the Consortium and the complexity of the Project implementation and the innovative approach for implementing the Romanian Pilot solution. The article presents also technical aspects about „Ploiești Pilot” and the expected benefits of the solution implementation

Power Quality indicators are still conveyed into a classical paradigm of power systems where the steady state operation is governed by quasi-constant frequency. Moreover, distribution grids are considered as network structures with solely load behavior. The standards proposing power quality descriptors are built on models, which seem to limit the possibilities of achieving real time control targeting highly efficient energy transfer, at least in all-electric grids. In this paper the measurement data aggregation algorithms proposed in the well-known standard IEC 61000-4-30 are discussed based on an analysis performed on voltages and frequency measurements. Raw data are obtained from PMUs installed in various nodes of active distribution grids with reporting rate of 50 frames per second. New aggregation algorithms for frequency, rate of change of frequency and unbalance coefficient appear to be needed.

Emerging power systems are requiring changes on all layers: planning, operation and markets. Smart grids operation, including control of the energy flow in active distribution grids adds more challenges to the measurement layer. Presently there is a gap between the models used for the current and voltage waveforms in the corresponding measurement algorithms implemented by devices deployed in power systems and the functionalities (like choice of available reporting rates) of the new generation of synchronized measurement units (SMU). Overlooking these issues can determine a significant depreciation of the information mediated by the control systems that are relying on real-time measurements delivered by equipment. Moreover, several applications require an estimation of the measurement quality thus enabling an effective control: state estimation, power quality improvement, voltage control, frequency control, network parameter’ estimation etc. Wide Area Measurement and Control Systems (WAMCS) have to accommodate multiple measurement approaches: on one side, the existing time-aggregation based measurements offered by currently deployed Intelligent Electronic Devices in SCADA framework, including smart meters and other emerging units; while on the other side, the high-resolution waveform-based monitoring devices like Phasor Measurement Units (PMUs) with fault-recorder functionality. In this paper the case of frequency measurement is analysed, addressing the measurement paradigm on a long term vision of future energy systems.