The growing demand for the utilization of clean energy resources requires consideration of more efficient and economical ways in the usage of available resources and technologies. In the field of solar energy both the...
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The growing demand for the utilization of clean energy resources requires consideration of more efficient and economical ways in the usage of available resources and technologies. In the field of solar energy both the efficiency and the economics, i.e. the payback times are crucial questions for a more widespread application of this resource in the future. A novel solution and system are proposed in the paper aimed at enhancing the amount of energy that can be harvested from solar radiation in the same area. The basis of the method presented is a special construction of combined Photovoltaic/Thermal panels that can generate heat power to produce hot water, while the photovoltaic part provides electric power for covering the electric power consumption of loads, to supply its own electronic control units and to operate pump drives etc. The theoretical predictions of the electric part of the system are confirmed by laboratory test results. The system and the overall control structure, including the MPPT control, are presented assuming stand-alone operation but parallel operation is also possible.
In this paper are presented some new concepts of control applied in Power Systems. Are given the architectures and methodologies based on the agents theory. The complexity of Power Systems is included into a new parad...
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ISBN:
(纸本)9783902661388
In this paper are presented some new concepts of control applied in Power Systems. Are given the architectures and methodologies based on the agents theory. The complexity of Power Systems is included into a new paradigm - Complex Adaptive Systems - and the modelling and control of Power Systems based on intelligent agents are considered. Some concepts on hierarchical and heterarchical architectures which include different intelligent techniques are also presented in this paper.
The paper presents an original frequency domain decentralized controller design technique for guaranteed performance. The novelty consists in that the designed decentralized controller guarantees the required performa...
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The paper treats a simple SISO control tool that uses classical nonlinear controllers. Description of basic functions and programs and several examples of their use comprise the main part of the paper. The tool forms ...
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The paper presents the measurement results of the noise level of a power transformer. The noise sources occurring in the transformer are presented, and the method applied and the measuring tools used are characterized...
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ISBN:
(纸本)9781627480000
The paper presents the measurement results of the noise level of a power transformer. The noise sources occurring in the transformer are presented, and the method applied and the measuring tools used are characterized. The measurements were taken in 29 points located around the transformer. The evaluation of noise was carried out based on the revised coefficient of the acoustic pressure level. The research work results presented enable the evaluation of the influence of the noise of the unit under study on its environment and make it easier to diagnose the degrees of wear of the fans installed in transformer coolers.
The paper will present the wavelet analysis results using continuous and discrete wavelet transforms of vibrations of a power transformer tub installed on the block of a conventional, thermal condensation power statio...
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ISBN:
(纸本)9781627480000
The paper will present the wavelet analysis results using continuous and discrete wavelet transforms of vibrations of a power transformer tub installed on the block of a conventional, thermal condensation power station. The research tests were carried out during a regular transformer operation in industrial conditions. The measurements were taken from the point of view of the evaluation of the influence of the vibrations registered on the analysis results of the acoustic emission signals generated by partial discharges that can occur in paper-oil insulation systems of power transformers. Moreover, the analyses carried out were supplemented with the research results obtained in laboratory conditions during the measurements taken in the high-voltage testing station of high-voltage power appliances. The influence of the loosened screws fastening the lid of the transformer tub on the time-frequency analysis results obtained of the vibrations registered was investigated. Moreover, the range of the research work carried out referred to the evaluation of the influence of the changes of the pressure force of the metal plates forming the transformer core on the vibration measurement results were obtained. In summary, the evaluation of usefulness was presented and the range of the time-frequency analysis application possibilities, and especially wavelet transforms, in diagnostics of power transformers using the acoustic methods was characterized.
The subject matter of this paper refers to vibroacoustic measurements of high power transformers. The evaluation method of the transformer technical condition, based on the measurements of mechanical vibrations of its...
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ISBN:
(纸本)9781627480000
The subject matter of this paper refers to vibroacoustic measurements of high power transformers. The evaluation method of the transformer technical condition, based on the measurements of mechanical vibrations of its tub, is characterized. The elements of the measuring set-up, which were used during the registration of the signals coming from the core and winding vibrations of a given transformer unit, transferred by the tub, are presented. Based on the criterion values of the vibroacoustic parameters measured: root-mean-square value of the vibration acceleration and the vibration spectrum amplitude in the frequency range from 0 to 3000 Hz, the evaluation of the technical condition of the power appliance under study was carried out.
The paper presents research results of electrokinetic zeta potential that exists in the electrical double layer on the border of the solid and liquid phases. For zeta potential examination, samples in the colloid form...
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The paper presents research results of electrokinetic zeta potential that exists in the electrical double layer on the border of the solid and liquid phases. For zeta potential examination, samples in the colloid form were used, the continuous (dispersing) phase of which was constituted by dielectric liquid mixtures formed on the base of simple hydrocarbons (hexane, cyclohexane, toluene), and the solid (dispersed) phase was constituted by materials in a disintegrated form (aluminum, copper, steatite, Al-70). The measurements were taken with Zetasizer 2000 - by Malvern Instruments (UK). Volume density of charge qw on the border of the solid and liquid phases, responsible for generation of electrostatic charges, was determined based on the measured zeta potential and physicochemical properties of the liquids under study.
In this paper we introduce a discrete event system model of immune systems of mammalians using Markov Decision Processes based on Petri Nets Models. Based on immunological principles we propose an approach in order to...
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In this paper we introduce a discrete event system model of immune systems of mammalians using Markov Decision Processes based on Petri Nets Models. Based on immunological principles we propose an approach in order to study the mechanisms that govern the immune system's functionality. A two-module algorithm is developed, which launch a specific action against an anomalous situation. The Petri nets tools are assumed in this approach. Also, Markov Decision Processes (MDPs) with a truncated state space to the problem with infinite state space considered. We also propose a new algorithm to build a large model (e.g., a macro-model) of immune mechanisms of mammalians. We show that an optimal stationary policy exists and we apply the results of [1] to a dynamic scheduling problem of the immunological response to external stimuli.
In this paper are presented some new concepts of control applied in Power Systems. Are given the architectures and methodologies based on the agents theory. The complexity of Power Systems is included into a new parad...
详细信息
In this paper are presented some new concepts of control applied in Power Systems. Are given the architectures and methodologies based on the agents theory. The complexity of Power Systems is included into a new paradigm – Complex Adaptive Systems – and the modelling and control of Power Systems based on intelligent agents are considered. Some concepts on hierarchical and heterarchical architectures which include different intelligent techniques are also presented in this paper.
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