P. G. Vidal

Universidad de Jaén | UJAEN · Department of Electric Engineering

Combining complementarity services such as frequency containment reserve (FCR) and photovoltaic self-consumption (PV SFC) can increase revenues for household-prosumers supported by battery/supercapacitor-based hybrid energy storage systems (HESSs). Nonetheless, to calculate the best financial profitability, optimization algorithms should be applied...

The industrial sector has a great opportunity to reduce its energy costs through distributed generation. In this sense, the potential of photovoltaic self-consumption systems in the industrial cooling and refrigeration sector is shown. Two industries with photovoltaic self-consumption installations are shown and the electricity consumption profile...

Various challenges should be considered when measuring photovoltaic array power and energy in pulse width modulation (PWM) charge controllers. These controllers are frequently used not only in stand-alone photovoltaic (SAPV) systems, but may also be found in photovoltaic (PV) self-consumption systems with battery storage connected to the electricit...

Because of vehicle-to-grid (V2G) growth, the provision of ancillary services by V2Gs is now required in the most recent network codes. A lack of primary frequency control (PFC) and dynamic grid support (DGS) in V2Gs could thus be detrimental to power system stability. This research presents a detailed V2G model with a hybrid energy storage system (...

This paper describes a multiterminal DC compact node consisting of voltage-source converters and DC-DC converters as a promising arrangement to feed electric vehicle (EV) charging stations with renewable power sources. This research analyzed the behavior of the node currents under DC faults, and more specifically their natural response, which can p...

Load duration curve (LDC) and output duration curve (ODC) are a very useful graphic tools to analyze the behaviour of an electric system both for demand purposes and for generation ones, respectively. Despite that, the use of this tool is not much extended in photovoltaics systems, not even in grid connected PV systems. However, its utilization may...

The detection of irregularities such as a fraudulent branch line or a fault in short-length low voltage (LV) lines is of great interest for electricity supply companies as well as for other businesses. This paper describes and systematizes new techniques that afford in-depth knowledge of the occurrence of irregularities in these lines for the first...

This research provides a detailed overview of the design and functionalities specified in electrical protection requirements for the grid-interconnection systems of a smart dc node used to feed electric vehicle (EV) charging stations. The survey focuses on protection relays. The multi-terminal dc node connects a 0.4-kV ac secondary distribution net...

A multi-terminal dc node consists of voltage-source converters (VSCs) and dc-dc converters (DC-DCCs) is presented in this paper as promising topology to feed electric vehicle (EV) charging stations from renewable power. The research focuses on the detailed analysis of the characteristic behaviour of node currents under dc faults, and in particular...

This paper describes a hitherto unstudied malfunction that can occur in the protection system of distribution networks (DNs) in the presence of large photovoltaic plants (LPVPs). The focus here is on the phase-balance current (PBC) protection of overhead or blended feeders back-fed by LPVPs. This study used the DNs belonging to ENDESA Distribución...

Most of electric energy is generated in large centralized plants, transmitted through high-voltage transmission systems and then distributed to consumer via medium and low-voltage distribution networks, however, the Distributed Generation (DG) it is gained importance. Photovoltaic technology is a type of GD and most of the newest photovoltaic syste...

The photovoltaic technology is one of the distributed generation energy sources that has experienced a great development in the last years, where most part of these installations are connected to the network. This growing increase of photovoltaic-distributed generation systems embedded in the distribution networks is causing power quality issues. C...

CPV modules are influenced by incident irradiance, air temperature and incident spectrum. However, the study of these effects and the ability to quantify them individually is not easy and it is still under study. The aim of this paper is describe a procedure to study the influence of air temperature in the maximum power point independently of the i...

For the behavior of concentrator photovoltaic systems technology under real conditions to be understood, different modules from different manufacturers were measured in a new research center in Jaén. The influence in the power and the efficiency of irradiation levels, air temperature, and the influence of air mass were under study for 6 months. Pma...

Assessing the correct operation of PV grid-connected systems (PVGCS) is paramount not only for mere energy and profitability concerns but also for safety reasons. Intended to this purpose, the IEC 62446 standard is open to some tests to be required in some circumstances, in addition to those stated in this document. Our work proposes a procedure to...

Photovoltaic devices are in a mature technological stage with a long and wide field experience; but if this source of energy wants to compete against other renewable energy sources or even to get into the traditional energy generation system, it is necessary a novel scientific progress in the behavior of these photovoltaic systems. In this challeng...

Currently, the electromagnetic compatibility (EMC) poses the following challenges for photovoltaic-distributed generation (PV-DG) units connected to the distribution network: a) PV-DG equipment should manage emissions as a 'product' with specific tests under a given set of conditions; b) PV-DG units should be incorporated as a 'user', and its emiss...

The recent research and field experiences in CPV systems have proved that this technology has present and potential advantages when compared with other sources of energy. Despite of that, if this technology wants to initiate its learning curve with the increment of the production and the consequent price reduction, it is necessary an institutional...

Protection against electric shock in photovoltaic generators (PVGs) with active protective measures requires an in-depth knowledge of the electrical behaviour of PVG insulation and PVG response under operating conditions with insulation faults. On the one hand, this knowledge can be obtained with an equivalent circuit model that characterises this...

Concentrator Photovoltaic (CPV) is showing a growing trend in the energy market as a consequence of the big investment made by the Photovoltaic industry; but this industrial and commercial growth will be successfully possible with the simultaneous creation of standardization norms that certify the reliability and durability of the CPV systems manuf...

In view of all the concerns associated with fossil fuels and energy demand it is appropriate to investigate the large number of abandoned small hydropower plants.In order to solve the difficulty implied, by a viability study on the refurbishment of a small hydropower plant, a series of simple equations has been developed based on the economic optim...

This paper assesses the protection against electric shock in a photovoltaic generator (PVG), the DC side of a PV installation. Within this context, we discuss the applicability of the protection requirements of the International Electrotechnical Commission 60364, the international standard that provides guidelines for wiring in low-voltage (LV) ele...

One of the most important elements on the recovery of a small hydro-power plant is the electro-mechanical equipment (turbine–alternator), since the cost of the equipment means a high percentage of the total budget of the plant. The present paper intends to develop a series of equations which determine its cost from basic parameters such as power an...

The aim of this paper is to give scientific background and essential assumptions to be introduced into the design of lightning and surge protection in photovoltaic installations (PVIs), with particular emphasis on the aspects of standardization to be covered. For this purpose, the relevant protective measures given in the standards for conventional...

This paper is focused on the personal safety on the dc side of PV generators. It deals with the adaptation and application in PV generators of proposed protective measures of the international standard IEC 60364. Different operational properties of PV generators in comparison to conventional ac low-voltage systems require this revision.

The adaptation and application of some active protective measures of international Standard IEC 60364 against electric shock in PV generators (PVGs) that involve the utilization of protective devices (PDs) require a deep knowledge of the behaviour of electric insulation of the PVG. In this paper we propose a model of equivalent electric circuit tha...

A comprehensive surge and lightning protection design concept for PV systems (PVSs) is described in detail in this paper. For this purpose, the relevant protective measures given in standards for conventional low-voltage power distribution systems (CLVPDSs) are adapted. This revision is required due to the specific characteristics of PVSs different...

The adaptation and application of some active protective measures of international Standard IEC 60364 against electric shock in PV generators (PVGs) that involve the utilization of protective devices (PDs) require a deep knowledge of the behaviour of electric insulation of the PVG. In this paper we propose a model of equivalent electric circuit tha...

The adaptation and application of some active protective measures against electric shocks in photovoltaic (PV) generators that involve the utilization of protective devices (PD's) require a deep knowledge of the behaviour of electric insulation of the PV generator. In this paper we propose a model of equivalent electrical circuit that characterizes...

Ensuring personal safety in future PV installations is a key issue for the progress of this market. This is especially crucial having in mind the increasing electrical risk of these installations as their size is becoming larger and given their proximity to residential areas. Personal protection measures in conventional electric systems are gathere...

Many of the solutions to integrate PV in buildings have the special feature of placing the generator in transit areas where people can have access to inside zones of the installation (metalworks, modules, junction boxes, etc.). In these cases, if we also need a higher level of generation voltage, due to the generator size and efficiency reasons, th...

This project consists in the installation of four photovoltaic subgenerators connected to the low voltage grid at Jaen University Campus (Spain), with a total power of 200 kWp. The Univer Project is developed under the Thermie Programme of the EU, with a budget of about 1.8 M euros. The main objective is the integration of a medium scale PV plant u...

This paper is intended to prove an economic profitability of the by-products obtained from the olive-grove in Jaen (Spain). There is a two-fold aim, on the one hand, the calculation of the biomass total potential originated from the olive-grove in Jaen, analysing the available potential and the viable economically potential, eliminating the zones o...

The aim of this paper is to develop a methodology that allows to know a optimal size of a photovoltaic (PV) generator in a building (dwellings, commercial buildings, etc.). The adopted design criterion is to optimize the profitability and the amortization of PV installations. There is an optimal maximum size for each building, the profitability of...

The aim of this paper is the analysis of the concentration achievable, without loss of rays, for a receiver located in an optically dense medium, presenting an interface of separation with the air either flat or spheric.