It is well known that in a photovoltaic (PV) plant, the modules are connected to switch-mode power converters to enhance the power output in every environmental condition. This task is performed by the maximum power point tracker (MPPT), which provides a current or voltage reference to the converter. Traditional perturb and observe or incremental conductance algorithms are not efficient in rapidly changing conditions, whereas a model-based (MB) MPPT offers a better dynamic performance. Because it is relatively easy to obtain an accurate model of a single PV panel, thus predicting the maximum power point voltage for given environmental conditions, MB MPPTs seemed to be attractive for employing in module integrated converters. Conventional MB MPPT algorithms, however, usually require an expensive pyranometer to properly operate. In this paper, starting from a new set of equations modeling a PV module, a novel MB MPPT technique, which does not require the direct measurement of the solar radiation, is proposed and experimentally validated

This study presents an overview of the results obtained during the first year of the SmartNet project, which aims at comparing possible architectures for optimised interaction between transmission system operator (TSOs) and distribution system operator (DSOs), including exchange of information for monitoring as well as acquisition of ancillary services (reserve and balancing, voltage regulation, congestion management), both for local needs and for the entire power system. The results concerning TSO-DSO coordination schemes, market design and information and communication technology (ICT) architectures are shown along with the layout of the three technological pilot projects.Additionally, this paper provides insight on the three physical pilots. Five TSO-DSO coordination schemesThe need for increased cooperation between TSOs and DSOs is widely recognised by regulators [1,2]. Within SmartNet, five 24th International Conference & Exhibition on Electricity Distribution (CIRED)

The growing number of installed photovoltaic (PV) plants is making the simulation of their behavior and their effects on the power network more and more relevant. In this context, an accurate yet simple model of the panels is beneficial for evaluating the power production as well as the system efficiency in off-line and on-line analysis. In the preliminary design stages of large plants, this kind of model can support design and decision making, allowing for the simulation of the entire plant and the testing of various power architectures. During the operation, such models may support monitoring, diagnostic, and control functions. In this paper, a model of PV panel, suitable for the aforementioned applications, is presented together with a simple procedure for the identification of its parameters. The critical issues related to the measurement and the estimation of the required environmental quantities are analyzed together with their main metrological requirements. Finally, the experimental validation of the proposed model and algorithms is presented using as a case study the estimation of the energy production of a domestic solar plant

The continuously growing distributed generation and the business potential for demand response are gradually enabling significant provision of flexibility and reserve towards distribution networks. For this reason, transmission and distribution system operators need to coordinate their operation in order to develop efficient market arrangements that can help utilize all the resources capable of providing ancillary services. SmartNet project investigated the potential interaction schemes between network operators, together with the possible new services devoted to the optimal distribution grid management. This paper summarizes the main challenges in simulating complex electricity systems and flexibility markets for three European countries (Italy, Denmark and Spain) in 2030 scenarios. The simulation results are then analyzed using cost-benefit analysis and regulatory conclusions are deduced.

The renewable energy industry has been growing\ud remarkably in the last years and the Fukushima event has\ud given a further incentive. In this context, solar radiation\ud represents one of the most accessible and clean energy\ud resources. For this reason the number and size of the\ud photovoltaic (PV) systems is growing and consequently the\ud amount of the investments and the related opportunities and\ud risks are increasing. Therefore, the optimization of electrical\ud performances of PV plants and the assessment of their\ud quality and reliability are important for both the investors\ud and the manufacturers. In a previous work some aspects,\ud fundamental for the efficiency evaluation of PV panels,\ud have been considered with particular attention to the\ud presence of pollution and dust on the panel surface. On the\ud basis of the results so obtained, an experimental activity\ud based on the electrical characterization of some PV modules\ud in presence of powder is proposed in this paper as evolution.\ud The results, in terms of power analysis, were analyzed by\ud means of a statistical approach in order to identify the\ud behavior of PV modules, with a given confidence interval.\ud The final aim is to use a PV panel as “reference panel” in\ud order to monitor the operating condition of a more complex\ud PV plant

As well known, the market of PV systems is having a great development nowadays. In this process both companies and governments require to evaluate the projects of PV plants both in terms of revenue and quality. Therefore accurate tools for predicting their performances are becoming more and more important. The accuracy of the estimation is key for photovoltaic applications since this technology is characterized by quite low efficiency and high fixed costs. In this scenario, it is extremely important to develop models of each component of the system in order to evaluate the PV plant behavior in any working condition. In this paper a flexible model of PV module suitable for off-line and on-line simulation will be presented and discussed. It will be shown that beside its simplicity, the accuracy is very good. Furthermore its parameters can be easily measured or estimated from the rated values

The continuously increasing number of Photovoltaic (PV) plants has stimulated the research in order to increment their overall efficiency. Usually, the efforts have been focused on the research of innovative materials and in general on the optimization of the photovoltaic conversion. Pollution due to the traffic, to the industrial activities or to the residential heating can reduce the efficiency of the PV plant. However, this phenomenon has been rarely investigated. It is important to highlight that these losses may have a significant impact in PV module and plant performances thus reducing the financial incomes in a nonnegligible way. This paper present and discuss a method which allows to choose the optimal maintenance interval for a PV plant. The method, starting from the costs related to the cleaning of the panels, compares them to the economic losses due to the decrease of the efficiency

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