One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free...One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free system of electric and gravimagnetic charges and currents and generated by them EGM-field. By using generalized functions theory the fundamental and regular solutions of this system are determined and some of them are considered (spinors, plane waves, shock EGM-waves and others). The properties of these solutions are investigated.展开更多
One the base of differential algebra of biquaternions, the one model of electro-gravimagnetic interactions of electric and gravimagnetic charges and currents has been constructed. For this, three Newton laws analogues...One the base of differential algebra of biquaternions, the one model of electro-gravimagnetic interactions of electric and gravimagnetic charges and currents has been constructed. For this, three Newton laws analogues are used. The closed system of biquaternionic wave equations is constructed for determination of the charges-currents and electro-gravimagnetic fields and united field of interactions. The equation of charge-current transformation is like the generalization of biquaternionic presentation of Dirac equation. The properties of its solutions are described, depending on properties of external EGM field. The biquaternions of energy-pulse of EGM-field and charges-currents are considered. The energy-pulse of EGM-interactions is calculated.展开更多
To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer （AT） feeding systems for high-speed railways in China. However,...To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer （AT） feeding systems for high-speed railways in China. However, no systematic algorithm yet exists to evaluate the consistency of the current distribution of short-circuit tests. A methodology is proposed in this paper to address this problem. Based on Kirchhoff’s current law and the generalized method of symmetrical components, the current deviations of the AT feeding systems are analysed and then normalized with the short-circuit current as they vary greatly with systems and short-circuit sites. It is also found that the short-circuit current varies with the calculation methods, and its unbiased standard deviation also reflects the consistency of the short-circuit test. The mean and maximum of the current deviations, as well as the unbiased standard deviation of the short-circuit current, show the consistency of the short-circuit test from different aspects,although the last two items are highly relevant. Therefore, a unified evaluation index is defined as the sum of the three items, and then applied in two case studies to test its performance. The results show that, the proposed index canclearly distinguish the consistency of the short-circuit tests and may be used to sort the short-circuit tests for fault location systems. Besides, some short-circuit tests may have very poor consistency indices, and thus are not applicable to the tuning of fault location systems. In the authors’ opinion, the determination of the threshold of the proposed index needs further investigation.展开更多
This paper is concerned with novel power law of turbulent energy spectrum and the relevant experiment in tidal current. The power law in the inertial sub-range has been proposed in such a way that the power of the one...This paper is concerned with novel power law of turbulent energy spectrum and the relevant experiment in tidal current. The power law in the inertial sub-range has been proposed in such a way that the power of the one-dimensional turbulent energy spectrum varies from 0 to -2 approximately, but it is accompanying the small oscillation with increasing the wave number. The well-known Kolmogorov -5/3 power law is merely one facet, to appear within the present proposed novel power law. The turbulent energy spectra (Su, Sv, Sw) in x-, y-and z-directions, respectively oscillate with the wave number. It is found that the turbulent in the tidal currents is three dimensional, and the intermittence of momentum transport is a predominant and characteristic feature in tidal current.展开更多
针对光伏并网系统在最大功率点跟踪(maximum power point tracking,MPPT)控制下直流侧电压振荡引起的间谐波电流现象,结合光伏逆变器控制系统特点,建立了单级式光伏并网系统解析模型。分析了直流侧电压振荡到交流侧间谐波电流的传变规律...针对光伏并网系统在最大功率点跟踪(maximum power point tracking,MPPT)控制下直流侧电压振荡引起的间谐波电流现象,结合光伏逆变器控制系统特点,建立了单级式光伏并网系统解析模型。分析了直流侧电压振荡到交流侧间谐波电流的传变规律,并通过仿真实验验证了传变规律的准确性。分析了MPPT控制参数和逆变器控制参数对光伏并网系统输出间谐波电流的影响。仿真结果表明MPPT控制参数影响间谐波电流幅值和频率分布,逆变器控制参数在不同频段下对间谐波电流幅值影响不同。展开更多
文摘One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free system of electric and gravimagnetic charges and currents and generated by them EGM-field. By using generalized functions theory the fundamental and regular solutions of this system are determined and some of them are considered (spinors, plane waves, shock EGM-waves and others). The properties of these solutions are investigated.
文摘One the base of differential algebra of biquaternions, the one model of electro-gravimagnetic interactions of electric and gravimagnetic charges and currents has been constructed. For this, three Newton laws analogues are used. The closed system of biquaternionic wave equations is constructed for determination of the charges-currents and electro-gravimagnetic fields and united field of interactions. The equation of charge-current transformation is like the generalization of biquaternionic presentation of Dirac equation. The properties of its solutions are described, depending on properties of external EGM field. The biquaternions of energy-pulse of EGM-field and charges-currents are considered. The energy-pulse of EGM-interactions is calculated.
文摘To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer （AT） feeding systems for high-speed railways in China. However, no systematic algorithm yet exists to evaluate the consistency of the current distribution of short-circuit tests. A methodology is proposed in this paper to address this problem. Based on Kirchhoff’s current law and the generalized method of symmetrical components, the current deviations of the AT feeding systems are analysed and then normalized with the short-circuit current as they vary greatly with systems and short-circuit sites. It is also found that the short-circuit current varies with the calculation methods, and its unbiased standard deviation also reflects the consistency of the short-circuit test. The mean and maximum of the current deviations, as well as the unbiased standard deviation of the short-circuit current, show the consistency of the short-circuit test from different aspects,although the last two items are highly relevant. Therefore, a unified evaluation index is defined as the sum of the three items, and then applied in two case studies to test its performance. The results show that, the proposed index canclearly distinguish the consistency of the short-circuit tests and may be used to sort the short-circuit tests for fault location systems. Besides, some short-circuit tests may have very poor consistency indices, and thus are not applicable to the tuning of fault location systems. In the authors’ opinion, the determination of the threshold of the proposed index needs further investigation.
文摘This paper is concerned with novel power law of turbulent energy spectrum and the relevant experiment in tidal current. The power law in the inertial sub-range has been proposed in such a way that the power of the one-dimensional turbulent energy spectrum varies from 0 to -2 approximately, but it is accompanying the small oscillation with increasing the wave number. The well-known Kolmogorov -5/3 power law is merely one facet, to appear within the present proposed novel power law. The turbulent energy spectra (Su, Sv, Sw) in x-, y-and z-directions, respectively oscillate with the wave number. It is found that the turbulent in the tidal currents is three dimensional, and the intermittence of momentum transport is a predominant and characteristic feature in tidal current.
文摘针对光伏并网系统在最大功率点跟踪(maximum power point tracking,MPPT)控制下直流侧电压振荡引起的间谐波电流现象,结合光伏逆变器控制系统特点,建立了单级式光伏并网系统解析模型。分析了直流侧电压振荡到交流侧间谐波电流的传变规律,并通过仿真实验验证了传变规律的准确性。分析了MPPT控制参数和逆变器控制参数对光伏并网系统输出间谐波电流的影响。仿真结果表明MPPT控制参数影响间谐波电流幅值和频率分布,逆变器控制参数在不同频段下对间谐波电流幅值影响不同。
