159 research outputs found

    Network-centric technologies for control of three-phase network operation modes

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    Purpose. The development of the control system for three-phase network is based on intelligent technologies of network-centric control of heterogeneous objects. The introduction of unmanned aerial vehicles for monitoring of three-phase network increases the efficiency of management. Methodology. The case of decomposition of the instantaneous capacities of the fixed and variable components for 3-wire system. The features of power balance for the different modes of its functioning. It should be noted that symmetric sinusoidal mode is balanced and good, but really unbalanced, if the standard reactive power is not zero. To solve the problem of compensation is sufficient knowledge of the total value of the inactive components of full power (value of the inactive power) without detail. The creation of a methodology of measurement and assessment will require knowledge of the magnitudes of each inactive component separately, which leads to the development of a unified approach to the measurement and compensation of inactive components of full power and the development of a generalized theory of power. Results. Procedure for the compensation of the current of zero sequence excludes from circuit the source, as the active component of instantaneous power of zero sequence, and a vector due to a current of zero sequence. This procedure is performed without time delay as it does not require integration. Only a 3–wire system with symmetrical voltage eliminates pulsations and symmetrization of the equivalent conductances of the phases of the task. Under asymmetric voltage, the power is different, its analysis requires the creation of a vector mathematical model of the energy processes of asymmetrical modes of 3–phase systems. Originality. The proposed method extends the basis of the vector method for any zero sequence voltages and shows that the various theories of instantaneous power three wired scheme due to the choice of a basis in a two-dimensional subspace. Practical value. The algorithm and software implementation for the decomposition of the zero sequence current, which allocated the procedure of obtaining null-balanced vectors of phase and interfacial voltage, calculation of active and inactive instantaneous power is zero balanced mode. The simulation results obtained in the software package Matlab by the method of visual programming in Simulink.Интеграция интеллектуальных и сетецентрических технологий в процесс управления режимами работы трехфазной сети обеспечивают оперативность компенсации нелинейностей в системе за счет ортогонального разложения тока и использования метода базисных функций для минимизации потерь

    The development of the theory of instantaneous power of three-phase network in terms of network centrism

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    Purpose. Information technologies allow multidimensional analysis of information about the state of the power system in a single information space in terms of providing network-centric approach to control and use of unmanned aerial vehicles as tools for condition monitoring of three-phase network. Methodology. The idea of energy processes in three independent (rather than four dependent) curves vector-functions with values in the arithmetic three-dimensional space adequately for both 4-wire and 3–wire circuits. The presence of zero sequence current structural (and mathematically) features a 4-wire scheme of energy from a 3-wire circuit. The zero sequence voltage caused by the displacement of the zero voltage phases. Offset zero in the calculations can be taken into account by appropriate selection of the reference voltages. Both of these energetic phenomena with common methodical positions are described in the framework of the general mathematical model, in which a significant role is played by the ort zero sequence. Results. Vector approach with a unified voice allows us to obtain and analyze new energy characteristics for 4–wire and 3–wire circuits in sinusoidal and non-sinusoidal mode, both in temporal and frequency domain. Originality. Symmetric sinusoidal mode is balanced, even with non-zero reactive power. The converse is not true. The mode can be balanced and unbalanced load. The mode can be balanced and unbalanced voltage. Practical value. Assessing balance in network mode and the impact of instantaneous power on the magnitude of the losses, will allow to avoid the appearance of zero sequence and, thus, to improve the quality of electricity.Обеспечение сетецентрического подхода к режиму управления трехфазной сетью и оценка сбалансированности режима сети с учетом влияния мгновенной мощности на величину потерь даст возможность исключить появление нулевой последовательности и, тем самым, повысить качество электроэнергии

    Assessment of the antifungal activity of the violacein-forming strain Janthinobacterium sp. B-3515 against the mould fungus Alternaria brassicicola F-1864

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    A study of antifungal properties of violacein-forming strain Janthinobacterium sp. B-3515 as well as its secondary metabolite, violacein, against Alternaria brassicicola F-1864 is presented. Regardless of the presence of bacteria, mycelium growth in the first two days proceeded at the same rate. The effect of the bacterial strain was manifested after the third day of incubation. In general, during co-culture, the bacterial strain statistically significantly reduced the average growth of the mycelium of the mould fungus by 10

    Nonlinear elastic properties of decagonal quasicrystals

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