Ferdinanda Ponci

Multiagent based power systems monitoring platform: a prototype

The paper presents a prototype of a monitoring platform that exploits the agent approach to improve the computation capability. The approach is supposed to be extremely useful for monitoring and diagnostic application where computational intensive task could be required. Preliminary experimental results complement the paper.

Time evolution of Haar spectra for periodic switching circuits

The study of time evolution of Haar spectra for periodic switching circuits is presented in this paper. The Haar transform is introduced and then applied to define the structure of the matrices involved in the analysis. This theory is then applied to the most important power converters in order to demonstrate the concrete possibility of the proposed approach in the analysis of power electronics circuits.

Power converter control design based on Haar analysis

This paper deals with the application of the Haar modeling approach for power converter control design. In previous papers, the authors introduced a new approach to the circuit analysis that is applicable to switching power converters and that contains the average-model as a particular case. In this paper, starting from the analysis of the properties of the matrix relating the time evolution of the Haar spectra between two switching periods, the application for control design is considered. This analysis seems to be particularly promising: also in this case the average-model constitutes a particular case. The main advantage of the proposed approach is the possibility to obtain very quickly information about a linear model for many possible situations with a really restricted computational effort. In particular, the user can forecast different scenarios, tracing interesting loci that can help the control designer to understand the system performances from a wider and global view.

Extending Haar domain analysis to DC/AC converters

This paper deals with the application of the Haar modeling approach to DC/AC converters. In previous papers, the authors introduced a new approach to circuit analysis that works particularly well with switching circuits and is therefore very appropriate for power converters. The converter model obtained using this approach contains the conventional average-model as a particular case. The previous analysis focused on a DC/DC converter, while in this paper a new extension to a three-phase DC/AC converter is proposed. The analysis is performed with the help of the Park transform. The results demonstrate the possibility to quickly obtain information about the steady-state condition of the system: this opens the way to detailed analysis and design optimization of many performance indexes of the system such as current ripple. Furthermore the equations extend the definition of the space vector concept introducing a multidimensional quantity in the Park domain to represent with a very small set of coefficients the whole information describing the system.

Measurement issues for performance assessment in large photovoltaic plants

The role of measurements is crucial for performance assessment in PV plants. Measurements are of critical importance both on a preliminary stage of model validation and on the subsequent stage of on-line monitoring. Measurement issues are particularly critical above all in large PV plants, where different environmental, geometrical and technical conditions may coexist. This paper addresses such issues, focusing on the features of the measurement system that should be guaranteed to obtain cost-effective model validation and performance evaluation in a large PV plant, with specific reference to a 18 MW plant installed in the north of Sardinia (Italy).