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As a direct consequence of the increasing demand. of energy and the need to decrease pollution in order to cope. with global warming, political, industrial and scientific interests. have combined to understand the way ICT technologies can. help to review all phases of energetic cycle, from generation. (through renewable sources), to accumulation and. transportation, until distribution. The union between ICT and. energy is usually identified as “Smart Grid”, to emphasize an. expectation change in what will be the Power Grid of the. incoming future. The aim of this study is to give some ideas. about the experimentation of new techniques of energy. acquisition through renewable sources (solar, chp, wind, etc.).. These techniques would guarantee more accessible prices for. production, improving performances, the overcome of those. constraints that did not allow the exploitation of potential. energy capacity of renewable sources. This grid will be made of. devices forming a control cycle that will check the station of. energy generation as much as the behaviour of single. consumers.

A very simple linear folding architecture for subranging ADC is presented. The preprocessing analog structure is constituted with 2n (with n number of bits) parallel circuits made with a simple subtracting node and with a series of two MOS switches able to join the functionalities of DAC, summing node and amplifier typical of classical subranging ADC. To validate the idea an accurate simulation of the single channels and of the whole structure has been realized.

A software to evaluate the performances of fuel cells. has been developed The software, initially developed for Molten. Carbonate Fuel Cells, allows to realize some measurement tests. on it, satisfying flexibility characteristics particularly appreciated. by qualified developer and researcher. The software allows to. verify both single cells and whole stack by the control of voltage. waveform versus time or current. Moreover it can be used also. for other kind of fuel cells.

A Data Acquisition USB Device has been. designed, developed, realized and characterized to be used in. Power Quality monitoring activities. The system. simultaneously manage 8 data acquisition channels to allow. acquisition on tri-phases plus neutral lines working at 499. samples per 50 Hz period. It can get external certified time and. voltage references to warranty certified measurements. The. system is directly powered by USB interface and use a. multiplatform FTDI Virtual ComPort drivers to yield a simpleto-. use and scalable device able to send and receive data over. High Speed RS232 virtual interfaces, without requiring any. advanced programming skill. The virtual serial communication. makes data acquisition software portable over many platforms,. regardless development environment and programming. language. The proposed device has been tested with custom. software written in C# and VB6, than in LabView and MatLab. environment, moreover it has been characterized applying the. most common ADC performing test to verify its behaviour.

A feedforward artificial neural network has been realized and trained to individualize subharmonics frequencies in an electric network. The adopted sampling window is fixed in 20 ms correspondent to a period of the fundamental frequency of 50 Hz, nevertheless the net is able to identify the subharmonics frequencies even if their period is not completed. The particular binary successive approximation structure realized for the ANN forecasts the scalability of the same net so allowing to recognize the subharmonics with a prefixed resolution. The net has been widely tested on synthesized signals.

Remote control of instrumentations and the connected measurement techniques represent an interesting topic particularly appreciated in some sectors as industry, research and e-learning. The current technologies allow to fully control modern instrumentation that is already conceived for this aim, while it is harder to manage old instrumentation not specifically designed for this kind of control. At the moment the costs are strongly conditioned by the current architecture that uses a personal computer as local server to manage the local instrumentations making impossible a really common use of these technologies. In this paper a system for remote controlling instrumentations implementing IEEE 488 or otherwise, based on an economic Wi-fi architecture, is described.

A Data Acquisition USB Device has been realized to be used in Power Quality monitoring activities. The adopted solution allows to perform 8 channel simultaneous data acquisition with external certified time and voltage references, working at 499 samples per 50 Hz period. The self-powered USB interface combined to multiplatform FTDI Virtual ComPort drivers yields a simple-to-use and scalable device; it can be driven simply sending and receiving data over High Speed RS232 virtual interfaces, without requiring any advanced programming skill. The virtual serial communication makes data acquisition software portable over many platforms, regardless development environment and programming language. The proposed device has been tested with custom software written in C# and VB6, than in LabView and MatLab environment.

An improvement of a feedforward artificial neural network for individualizing electric network subharmonics frequencies has been realized increasing the neural network resolution. Whishing to have a quick system able to signal the presence of subharmonics in real time, It has been fixed a sampling window of 20 ms equal to a period of an ideal fundamental frequency of 50 Hz. This choice obliges to pick up only a fraction of the subharmonics period that is not ever completed inside the sampling window making the classical spectral frequency recognition method unsuited. This obliges to transfer the problem of the their recognition on the neural network trained phase obtained by an appropriate discretization of the training set. The binary successive approximation structure has the merit of the scalability exploited in this article to increase the resolution than previous work. The net has been widely tested on synthesized signals.

Power quality is an important subject to correctly dimension protection devices and back up power systems for next generation of telecommunication network. In this paper it is presented an overview of some power quality data obtained using integrated instruments put inside Chloride's UPS, widely distributed in the world and active for quite a few years, allow statistical evaluations to derive some important convictions about the power quality situation, which are the electrical energy parameters particularly important for the design of new generation tIc apparatuses. The article is focused on the Italian situation and in detail analyzes the mains failures for each Italian region.

The need to deploy distributed power quality monitoring systems requires the development of circuits able to yield an accurate time reference that is easy to disseminate on specific monitoring sites. In this paper, the design and initial realization of a time reference continuously traceable to a Cs133 atomic standard is proposed. Such reference is based on the locking of the Cesium-derived L1 GPS satellites carrier and would simply require visibility of one GPS satellite in order to be operative. In particular, attention is focused on the hybrid design and realization of the carrier tracking section, with particular emphasis on its fundamental building blocks, such as the voltage controlled oscillator, mixers, and power dividers. The design procedure for the different blocks and some prototypes are discussed and preliminary measurements showing their functionality are presented.

This work shows an example of power quality (PQ) data of four important telecommunication sites placed in Rome, Italy. The data are collected, elaborated and analyzed by four self made instruments developed for this purpose and inserted in four automatic telecommunication exchanges kindly at our disposal by TELECOM, the most important Italian telecommunication company. The analysis shows the active and reactive power consumption and, for one site, the harmonic distortion.

A simplified architecture of subranging pure linear folding ADC is proposed. The device is based on the folding idea to eliminate the DAC, the summing node and the amplifier, fundamental elements of the classical architecture, replacing them by means of an analogical signal preprocessing parallel structure named “channels”. The presented circuit in addition to the advantage of a reduction of total conversion time than a classical subranging ADC, so approaching ADC flashes, is very simple and easy to build. An accurate simulation of the single channels and of the whole structure validate the idea. A first discrete circuit it has been realized and tested.

The research shows as the deep lack of knowledge by low voltage and domestic customers is made the most by the producers/suppliers to impose their will disappointing the ISO 9000 certification. A new way to build the relationships between these actors is suggested with the declared aim to formulate new type of agreement based on the quality of electrical energy appropriately measured.

A possibility to obtain a new time reference constantly locked to the Caesium-derived GPS satellites carriers was investigated by means of a new GPS receiver architecture able to lock the two GPS carriers and mix them to obtain a reference frequency with an accuracy close to the GPS one. This is very important in Perceived Power Quality distributed measurements systems where the exact knowledge of the events on the geographic compass is strongly joined to the capability to associate them an accurate time. A simulation of the carrier tracking loop has been performed. It shows how choosing appropriately the frequency of the low-pass filter of Costas loop, a modified PLL typically used in GPS system, it is possible to recover carriers in presence of high noise to signal ratio too. The front-end of the system able to select GPS frequencies, which is the first block of the entire system, was also realized.

An instrument based on FPGA technology able to determine in an only period and with a little number of samples the fundamental frequency of electrical net signal is been realized. The algorithm implemented on the instrument is a modified version of the well known Curve Fitting Algorithm (CFA) particularly suitable to determine Power Quality Parameters. A study of the uncertainty to evaluate the performances of the instruments is presented too.

A first comparison between data comes from an investigation on the Perceived Power Quality (PPQ) parameters effected on customers of Rome (Italy) and data measured of Power Quality (PQ) normed parameters in the same zone is presented. The results show how the intuitions and the experiences of the customers are verified. The PQ parameters have been measured by means a self made instrument developed ad hoc for this purpose.

A circuit able to protect electronic devices by overvoltages is proposed. A comparison among existing protection devices is discussed, pointing out the advantages of our system to satisfy specific requirements. Some measurements have been effected to verify the device's performances. An example of the use of this system in Perceived Power Quality instrument is proposed.

A monitoring of power quality parameters it is been effected inside four medium/low voltage transformer rooms of telecommunication power substations of the biggest Italian telecommunication society. The measurements have been realized by means of an appropriate self-made instrument that samples the three-phases with neutral lines of the mains for a total period of about two years. By the analysis of the parameters it is possible to determine which are the power quality parameters which the society is more sensible, so to suggest which are the parameters to monitor and to ask with more quality to the energy supplier society.

A new architecture of subranging ADC is proposed. Against a little increase of the number of comparators than a classical subranging architecture, the substitution of the DAC and summing node brings to a reduction of total conversion time, approaching it to an ADC flash behavior.

Many computing techniques are used to evaluate Power Quality parameters, each showing specific advantages and disadvantages. This paper presents an improvement of Curve Fitting Algorithm (CFA) having good accuracy in the estimation of the signal’s power quality parameters.

The Perceived Power Quality by costumers has been faced, starting from ISO 9000 Quality definition. An experimental investigation is presented on customers of Rome (Italy). By the results one demonstrates that fluxes of parameters defined on own manner by costumers, can be determined.

Quality parameters, each showing specific advantages. This paper presents an improvement of Curve Fitting Algorithm (CFA), having good accuracy in the estimation of the signal’s power quality parameters, in order to compare the Perceived Power Quality of complex networks electric systems explored, out of line, by a questionnaire supplied to people Pertaining to the Technology of Commerce that operate as a Filter

W sieciach elektroenergetycznych, zakłócenia mogą powodować problemy w urządzeniach elektronicznych. W związku z tym ich monitorowanie, ma fundamentalne znaczenie dla prawidłowego projektowania urządzeń ochronnych i kompensacyjnych. W artykule podjęto problem wykrywania zakłóceń "za pomocą dwóch różnych metod przetwarzania sygnałów: falek i transformaty Hilberta (HT). Metody te były badane przy różnych poziomach szumu i zniekształceń harmonicznych (THD). Stwierdzono przydatność HT do analizy krótkich przebiegów przejściowych i zakłóceń oraz podobnych zjawisk. (Falki i transformata Hilberta do wykrywania zakłóceń w krótkim czasie trwania w sieciach elektroenergetycznych) In electrical energy power network, disturbances can cause problems in electronic devices therefore their monitoring is fundamental to properly design the protection and compensation devices. In this paper we address the problem of disturbances’ detection by using two different signal processing methods: Wavelets and Hilbert Transform (HT). Methods were tested under different conditions of noise and harmonic distortion (THD) showing the Hilbert Transform can be used as a valid approach for this type of phenomena.

Starting from gas-chromatograms of samples of extra virgin olive oil, choosing most significant peaks, authors try to define a standard ortho-normal base be deposited for quality valuation

With a wide range of power electronics-related applications in power systems, harmonic currents are increasing at an alarming rate which has greatly deteriorated the power quality in electrical power networks. Moreover, some of electronic controlled equipments used in power systems, such as cycloconverters, produce sub-harmonics, a type of waveform distortion, which can severely degrade the power system performance. Therefore, they must be closely monitored. Moreover, Fast Fourier Transform cannot accurately analyze waveforms containing sub-harmonics because the synchronization of the sampling procedure to subharmonics is practically infeasible. The detection of subharmonics requires a different approach from that used for harmonics analysis. In most analysis methods the voltage waveform is expected to be a pure sinusoid with a given frequency and amplitude. Standard tools of harmonic analysis based on the Fourier transform assume that only harmonics are present in the investigated signal and the periodicity intervals are fixed, while periodicity intervals in the presence of interharmonics and sub-harmonics can be variable and very long. Two novel approaches to analyze non-stationary signals are shown in this paper. The first is the “Root-Music” harmonic retrieval method that is an example of high-resolution eigenstructure-based method, the second is a numerical method based on moving average.

The possibility to use the Curve Fitting Algorithm (CFA), for the Power Quality (PQ) parameters valuation foreseen by the EN 50160 Rule, is faced in terms of frequency determination. The comparison between the loop algorithm performance in the frequency determination and the thrown one, using a Taylor Series, truncated in terms of foreseen uncertainty, is presented.

Nowadays a large number of studies are being carried out on active vibration control, especially in the aeronautical gas turbine industry. Indeed, uncontrolled vibration in aeronautical engine blades can lead to fatigue failure with catastrophic consequences. For this reason, many efforts are made to implement an embedded active vibration control on rotors. Furthermore in this particular kind of application a compact, integrated and robust system, controlled by a wireless remote system, is necessary. Before designing the vibration active control it is mandatory to characterize the vibration monitoring system of the blade in order to develop a feedback system for active damping. To this regard a MEMS accelerometer for mobile applications (MEMSWMAA) may be considered a good choice, since the wireless features are relevant in a rotor vibration monitoring application, its cost is usually low and its size and weight allow to obtain a lower insertion effect. However, the metrological limits of this type of sensors are not well investigated. In this work a preliminary characterization of a MEMSWMAA for blade vibration monitoring application is proposed. In particular the authors evaluate the actual performance of MEMSWMAA by means of a direct and simultaneous comparison with a reference sensor. The frequency range of investigation (10 Hz up to 1080 Hz) includes the first three resonant frequencies of a cantilever beam that will be used in a future work to experimentally validate the vibration control algorithm.

Spectral leakage and picket-fence effects associated with the system fundamental frequency variation and improperly selected sampling time window prevents a direct application of the DFT algorithm with a constant sampling rate. In particular it’s very difficult to detect low level interharmoincs and subharmonics. In this paper we compare two methods, proposed in literature, evaluating the detection capability and accuracy in frequency spectrum estimation. Several tests in different condition has been effected for the comparison.

Ultrasound signal, received by an ultrasound (U.S.) machine from target under observation, has an impulsive form. Actual systems use a non-linear stage, as a logarithmic amplifier, to get its amplitude demodulation and to display it on U.S. scanner monitor. This work proposes an idea to realize a new input stage based on phase locked loop (PLL) system to obtain a more accurate amplitude demodulation. PLL, is an inherently slow system and it needs several cycles to reach phase lock, so it must be modified by means with a delay locked loop (DLL) to obtain more quickness from PLL. A first system has been realized and experimental results confirm the goodness of our idea.

The Guidance and Control system is a critical part of the design of a drone. This paper explains the study of a high accuracy attitude system for the SQUID TUG, a Tailless Underwater Glider drone. As the vehicle does not have movable surfaces, the entire manoeuvring system is geared to the buoyancy system and the centre of gravity displacement. We will examine the control system for a tailless AUV (Autonomous Underwater Vehicle) without any type of movable control surfaces embedded in the hydrodynamic flow whose actuators may require "waterways" through the hull.

The need to correlate as accurately as possible Time to the power quality events pushes towards the necessity to develop circuits able to yield a time reference that is referable to International Time Standards. Moreover, the necessity to deploy distributed power quality monitoring systems requires these time references to be easy to disseminate, making them available on specific monitoring sites. In this paper, the possibility to obtain a time reference continuously traceable to a Cs133 atomic standard is proposed, by locking the Cesium-derived L1 GPS satellites carrier by means of a specifically designed GPS receiver. Such time reference would simply require visibility of one GPS satellite in order to be operative. In particular, the overall architecture of such receiver will be first outlined and then attention will be focused on the design and realization of the VCO which is one of its fundamental building blocks. Measurements carried out on a prototype of the proposed VCO show that its performances are adequate for the aim.

A new platform for Power Quality measurement based on PIC 32 family microcontroller has been realized and tested. The board is able to determine the frequency of the mains implementing the Curve Fitting Algorithm and is able to detect punctual events as short interruptions. The device allows performing high accuracy measurements and is a good candidate as platform to use in civil suit in the subject of Power Quality analysis.

A very simple circuit for a 3-bits discrete pure linear analog preprocessing folding ADC is presented. The device is based on the folding idea: the DAC, the summing node and the amplifier, fundamental elements of the classical architecture, are eliminated and replaced with an analogical signal preprocessing parallel structure named “channels”. All channels are connected as a cascade and only three transistors constitute each one. The circuit has been widely analyzed by simulation and its simplicity guarantees easiness of realization, reduction of power consumption and reduction of total conversion time, making it close to the ADC flash. A first discrete circuit it has been realized and tested

This paper describes an integrated control system architecture with a high accuracy navigation system for an underwater glider. To optimize the glider performances, a centralized control system called "Glider Integrated Control System (GICS)" is provided: part of this system oversees the navigation function, based on an INS reference. Unlike an UAV system, in our case, some important inertial navigation error terms cannot be neglected due to the peculiar mission.

The problem of useful echoes identification in an Ultra Sound (U.S.) signal is faced. The used approach consists in the time re-arrangement of a paths matrix built utilizing the electro-acoustic equivalence. Some acoustic parameter identification of slabs encountered by U.S. wave has been demonstrated been possible, in particular cases. The precise time positioning of identified useful echoes has been obtained applying an improved Maximum Likelihood Estimator (M.L.E.). The great computational load of the method has been faced by a parallel computational structure measurement. Experimental on software performances are presented too.