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Time-frequency analysis is naturally the way of characterization of non-stationary signals. One fundamental parameter of the any-non-stationary is the Instantaneous Frequency Law of its components. The Instantaneous Frequency Law (IFL) estimation is usually subject of tracking in time-frequency domain, especially in the case of complex time-frequency structures. Using the concept of phase diagram...
Electrical arc faults represent a danger for today's power generation systems, and their detection can have a serious positive economic impact. In this paper we present a system for the detection and localization of DC electrical arc faults (typical for a photovoltaic power generation system). Our approach is based on the multidimensionality of the arc fault emissions, therefore we use a dual sensing...
Electrical arc faults that occur in photovoltaic systems represent a danger due to their economic impact on production and distribution. In this paper we propose a complete system, with focus on the methodology, that enables the detection and localization of the arc fault, by the use of an electromagnetic-acoustic sensing system. By exploiting the multiple emissions of the arc fault, in conjunction...
Wireless sensor networks are currently being deployed over a vast array of applications to collect, process and reliably transmit data from a source event to a data sink. This in turn requires reliable power supply, mainly in the form of primary or secondary batteries storing energy to supply the various functional discrete components along with accurate prediction of sensor node life time, based...
This paper presents two methods applied in the context of surveilling and localizing electrical arcs which usually occur in photovoltaic power systems. The wavelet analysis has proved to be very powerful in transient signal detection, namely in multiscale edge detection, thereby we use this method to detect the electrical arcs and to localize them in time. Secondly, we applied the recurrence plot...
In this paper, we present a new technique for detecting and localising defects in metallic structures, using ultrasound non-destructive inspection. This technique consists in applying a dual path inspection and the matched filter to a stepped frequency-type signal. This new technique is compared with classical non-destructive testing approaches. An experimental setup is presented that allows us to...
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