Lorenzo Peretto

CALIBRATION OF VOLTAGE AND CURRENT TRANSDUCERS USED WITH DSP. Research for the determination of indices for the analysis of the propagation of uncertainties in digital measurement systems. DISTRIBUTED MEASUREMENT SYSTEMS. Study of distributed and synchronized measurement systems for the identification of sources of transient disturbances in medium voltage networks. INNOVATIVE METHODS FOR THE OBJECTIVE MEASUREMENT OF LIGHT FLICKER. Synthesis of a mathematical model of the response of the eye-brain system to variations in luminance in order to measure the amount of annoyance produced by light flicker. TECHNIQUES FOR THE RELIABILITY ANALYSIS OF ELECTRONIC SYSTEMS. Creation of virtual tools for the analysis of the reliability of electronic systems and components. RELIABILITY TESTS FOR POLYPROPYLENE CAPACITORS. Design of a destruction test for newly developed polypropylene capacitors to verify safety in the event of out of service.

CALIBRATION OF VOLTAGE AND CURRENT TRANSDUCERS USED WITH DSP. In instrumentation based on DSP, the type B evaluation of the uncertainty on the measurements carried out is problematic as the accuracy specifications of the acquisition block refer to the generic sample, while the transducers are characterized with integral parameters. The method being studied is based on the comparison between the values of the signals acquired simultaneously at the input and output of the device under test and, through the comparison of the calibration curve of the device with the straight line of best fit and with the transduction characteristic ideal to obtain appropriate calibration indices, which can be used in the evaluation of uncertainty in measurements with DSP. DISTRIBUTED MEASUREMENT SYSTEMS. The availability at decreasing costs of acquisition devices that can be interfaced with personal computers (PCs) and the possibility of easily connecting to communication networks on a geographical scale have made the implementation of distributed architecture measurement systems possible. These systems are very often of the master-slave type; the local units (slaves) acquire the signals of the quantities to be monitored, carry out and send the measurement results (for example via the Internet) to a central unit (master) which processes the results. The research carried out in recent years has concentrated on the development of distributed measurement systems aimed at solving specific problems. Initially, the focus was on measuring harmonic pollution and evaluating the related responsibilities. Research is still oriented towards the development of a distributed system for identifying the sources of transient disturbances in medium voltage networks. The system uses an event detection block, GPS receivers for synchronization and GPRS for connection to the internet. ANALYTICAL MODELS AND EQUIPMENT FOR THE OBJECTIVE MEASUREMENT OF LIGHT FLICKER. Light flicker is caused by the fluctuation of the power supply voltage of a light source. The measurement of this effect occurs by processing the signal representing this voltage on the basis of a model referring to a 230 V, 50 Hz, 60 W incandescent lamp. Only a flicker measurement based on the analysis of light radiation can provide reliable information. To do this, however, it is necessary to have a model of the response of the eye-brain system to variations in luminance. The model being studied is based on the analysis of the mechanism of the pupillary reflex (pupillary light reflex model). The research carried out so far has shown that the proposed model correctly describes the behavior of the eye-brain system. The creation of a measurement instrument that implements this model is envisaged. TECHNIQUES FOR THE RELIABILITY ANALYSIS OF ELECTRONIC SYSTEMS. Virtual tools are studied for the analysis of the reliability prediction of electronic systems using the libraries and methodology suggested by MIL-HDBK-217F-N2 which implements the technique called Parts Stress Analysis in accordance with the CEI 56-29 standard. The program recalls mathematical models from the libraries to calculate the failure rate of the system as a function of multiple parameters such as the technological characteristics, the value of the applied stress, and the type, the environmental conditions, the construction type, the type of application, the production date, etc. The values of all these parameters can be entered by the user for each of the components used. In this way the operator can, in the design phase, vary the operating parameters of the individual components and verify the variation in both their failure rate and that of the system. RELIABILITY TESTS FOR POLYPROPYLENE CAPACITORS The research aims to identify a destruction test for metallized polypropylene capacitors with armatures made with the new segment technology. Faults must occur without risk of lightning and fire. The Conference Internationale des Grandes Réseaux Electriques (CIGRE) has created a Task Force led by prof. Mario Rinaldi tasked him with identifying such evidence and it is in this context that the research will develop. The German industry Steiner supplied capacitive elements made with different types of segmentations: the Italian companies Ducati Energia, Italfarad, ICAR, Arcotronics transformed them into finished capacitors. It is intended to carry out tests on these capacitors together with the Italian Quality Mark Institute (IMQ) to develop a destruction test that is significant for these capacitors. The research will be conducted in close collaboration with the aforementioned structures.