The method is based on that the waveform of the inrush distorts seriously, while the fault current nearly keeps sinusoid. The complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the EM...The method is based on that the waveform of the inrush distorts seriously, while the fault current nearly keeps sinusoid. The complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the EMD, then define and compute the projection area on X-axis of each IMF—, the specific gravity of SIMF—, and the maximum of —. We can get a new scheme of transformer-protection based on comparing the difference between inrush and fault current. Theoretical analysis show that the method can precisely discriminate inrush and fault current, fault clearance time is about 20ms. Moreover, it is convenient to achieve and hardly be affect by not-periodic component.展开更多
This paper has analyzed the dynamics mechanism of resource enterprises community vulnerability,selected the key factor of resources to establish a nonlinear dynamical model.The model reveals the constrained relationsh...This paper has analyzed the dynamics mechanism of resource enterprises community vulnerability,selected the key factor of resources to establish a nonlinear dynamical model.The model reveals the constrained relationship between the number of vulnerable enterprises and resource shortage rate,and the same relationship between t vulnerable enterprise numbers and the owning rate of resource market by the biggest enterprise in resource-type enterprises community of China.The results showed that,the shortage rate of resources take up more percentage than the occupancy of resource rate of the strongest enterprises in Enterprise community when D>q.the characteristics and patterns of the Chinese enterprise evolution are as follows,(1)The strongest enterprises n1 will decline or transform in the enterprise community.(2)The enterprises which survived after the shortage of resources will go through three stages:①resistance stage;②recovery stage;③stable stage.We believe that there are three movements that can make sure the resource-based enterprises community keep growing continuously in the competitive market for resources,(1)understand the enterprise resources shortage rate and the strongest enterprises share in resource rate in enterprise community,(2)follow the even-odd symmetry or odd-even symmetry laws based on the familiarity of a resource economy,(3)put the enterprises in the suitable position.展开更多
文摘The method is based on that the waveform of the inrush distorts seriously, while the fault current nearly keeps sinusoid. The complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the EMD, then define and compute the projection area on X-axis of each IMF—, the specific gravity of SIMF—, and the maximum of —. We can get a new scheme of transformer-protection based on comparing the difference between inrush and fault current. Theoretical analysis show that the method can precisely discriminate inrush and fault current, fault clearance time is about 20ms. Moreover, it is convenient to achieve and hardly be affect by not-periodic component.
基金This work was supported by Jiangxi University Humanities and Social Sciences Research Project of China[No.JC18118]the Humanity and Social Sciences Foundation of Ministry of Education of China(17YJAZH113)+1 种基金Hainan Provincial Natural Science Foundation of China[Grant No.417151]the Doctoral Scientific Research Foundation of Hainan Tropical Ocean University[Grant No.RHDXB201613].
文摘This paper has analyzed the dynamics mechanism of resource enterprises community vulnerability,selected the key factor of resources to establish a nonlinear dynamical model.The model reveals the constrained relationship between the number of vulnerable enterprises and resource shortage rate,and the same relationship between t vulnerable enterprise numbers and the owning rate of resource market by the biggest enterprise in resource-type enterprises community of China.The results showed that,the shortage rate of resources take up more percentage than the occupancy of resource rate of the strongest enterprises in Enterprise community when D>q.the characteristics and patterns of the Chinese enterprise evolution are as follows,(1)The strongest enterprises n1 will decline or transform in the enterprise community.(2)The enterprises which survived after the shortage of resources will go through three stages:①resistance stage;②recovery stage;③stable stage.We believe that there are three movements that can make sure the resource-based enterprises community keep growing continuously in the competitive market for resources,(1)understand the enterprise resources shortage rate and the strongest enterprises share in resource rate in enterprise community,(2)follow the even-odd symmetry or odd-even symmetry laws based on the familiarity of a resource economy,(3)put the enterprises in the suitable position.