Guillermo Velasco

Grid-connected PV systems energy extraction improvement by means of an Electric Array Reconfiguration (EAR) strategy: Operating principle and experimental results

This paper applies a dynamical electrical array reconfiguration (EAR) strategy on the PV modules of a grid-connected PV system based on a plant oriented (PO) configuration, in order to improve its energy production when the operating conditions of the solar panels are different, such as in the case of partial shadowing or module failure. The EAR strategy is carried out by inserting a controllable switching matrix between the PV generator and the central inverter, which allows the electrical reconnection of the available PV modules depending on their incident irradiance estimated values. As a result, the PV system exhibits a self-capacity for real-time adaptation to the PV generator external operating conditions in order to improve the energy extraction of the system. The paper details both the operating principle and a set of experimental results carried out on a 1.65 kWp EAR-based grid-connected system.

Irradiance equalization method for output power optimization in plant oriented grid-connected PV generators

A dynamic interconnection of PV modules based on an irradiance equalization algorithm in grid-connected systems based on a plant oriented configuration is presented. The maximum output power at the PV generator level obtained with approach is similar to that obtained in the module integrated configuration

Power sizing factor design of central inverter PV grid-connected systems: A simulation approach

This paper presents a simulation approach which can help in the preliminary power sizing design of a grid-connected PV system based on a single inverter configuration. Given a nominal peak power of the PV array, this simulation procedure leads to the PV inverter maximum rated power which maximizes the yearly injected energy to the grid.

Inverter power sizing considerations in grid-connected PV systems

This work is devoted to establish preliminary criteria helping in the choice of a central inverter power sizing in grid-connected PV systems in order to maximize the yearly energy injected to the grid. These criteria come from an estimation of the injected energy by means of a set of Matlabreg-based simulations involving a simulation-oriented model of the PV conversion chain, the environmental data of several PV Spanish sites as well as the PV installation mounting type characteristics. The simulation results show that the current practice of under-sizing the inverter maximum power with respect to the PV generator nominal power may not be the best choice in terms of yearly produced energy and also evidence the strong impact of the PV generator operating temperature in the choice of the optimal inverter power sizing.

Low consumption Flux-gate transducer for AC and DC high-current measurement

This work presents the design and implementation of a transducer system for the measurement of AC and DC high-current using the flux compensation technique in the measurement transformer, also called Flux- gate technology. The system can measure currents greater than 700 A (peak value) with a 100 kHz bandwidth measured at -3 dB. This equipment has been developed under the agreement of collaboration subscribed between the EUETIB-CEIB of the Technical University of Catalonia (UPC) and Group PREMO S.A. The Group PREMO S.A. is a Spanish company specialized in high-quality inductive components and leader in this sector.