Micaela Caserza Magro

Validation of ZnO surge arresters model for overvoltage studies

This paper presents an improvement of the procedure to determine the parameters of the simplified model for metal-oxide surge arresters, derived from the IEEE standard model. The main innovation introduced by the paper lays in the possibility to define an approximate dynamic model even if data about residual voltages for steep current pulse are not defined in the manufacturers data sheets. This model has a wide rangeability and its effectiveness is good for both medium- and high-voltage arresters. The effectiveness of the model was tested for several arresters of different manufacturers. The residual voltages reported in the datasheets and obtained by the manufacturers through a discharge test are compared with the simulations performed with Matlab. The possibility of defining a dynamic model for surge arresters even with missing data makes the proposed model a useful tool for insulation coordination studies involving steep front transients.

Reliability and availability performances of a universal and flexible power management system

This paper presents the results of the activities carried out by the authors within the European Project UNIFLEX-PM. The core of the activities dealt with the reliability and availability analysis of the new architecture proposed by the Consortium for a power management system to be used in the power distribution network. In particular, the contents of the paper address the analysis of the effects on system stochastic performances deriving from basic components wear-out phenomena, and the ones deriving from the adoption of different redundancy strategies and maintenance policies. Aim of these additional studies is to highlight the lack of a bottleneck from the dependability point of view, so paving the way toward the future development of an industrial product based on the new power converter architecture proposed and investigated during the project.

Detection of voltage transients to select and trigger control rules of SMES for power quality applications

The paper describes the preliminary results obtained in the HotSMESProject sponsored by the EU. The project has the goal to investigate the performances of the so-called High-Temperature Superconductor (HTS) when used in Superconducting Magnetic Energy Storage systems (SMES) used to improve the Power Quality (PQ).

Base reliability analysis for an universal and flexible power management system

This paper presents the results of the study carried out by the authors to estimate the reliability performances of an innovative modular power conversion architecture, developed within the UNIFLEX-PM EU project. The paper not only deals with the analysis of the base reliability, but also presents two further studies. Namely, the paper also addresses the analysis performed to identify the impact of basic components wear out on the system stochastic performances, and the analysis carried out to investigate the effects deriving from the adoption of different redundancy strategies as far as the reliability of the whole application is concerned.