Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus,the transfer function modeling and analysis of the open-loop Buck converter in a continuous co...Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus,the transfer function modeling and analysis of the open-loop Buck converter in a continuous conduction mode（CCM） operation are carried out in this paper.The fractional order small signal model and the corresponding equivalent circuit of the open-loop Buck converter in a CCM operation are presented.The transfer functions from the input voltage to the output voltage,from the input voltage to the inductor current,from the duty cycle to the output voltage,from the duty cycle to the inductor current,and the output impedance of the open-loop Buck converter in CCM operation are derived,and their bode diagrams and step responses are calculated,respectively.It is found that all the derived fractional order transfer functions of the system are influenced by the fractional orders of the inductor and the capacitor.Finally,the realization of the fractional order inductor and the fractional order capacitor is designed,and the corresponding PSIM circuit simulation results of the open-loop Buck converter in CCM operation are given to confirm the correctness of the derivations and the theoretical analysis.展开更多
In this work a method called “signal flow graph (SFG)” is presented. A signal-flow graph describes a system by its signal flow by directed and weighted graph;the signals are applied to nodes and functions on edges. ...In this work a method called “signal flow graph (SFG)” is presented. A signal-flow graph describes a system by its signal flow by directed and weighted graph;the signals are applied to nodes and functions on edges. The edges of the signal flow graph are small processing units, through which the incoming signals are processed in a certain form. In this case, the result is sent to the outgoing node. The SFG allows a good visual inspection into complex feedback problems. Furthermore such a presentation allows for a clear and unambiguous description of a generating system, for example, a netview. A Signal Flow Graph (SFG) allows a fast and practical network analysis based on a clear data presentation in graphic format of the mathematical linear equations of the circuit. During creation of a SFG the Direct Current-Case (DC-Case) was observed since the correct current and voltage directions was drawn from zero frequency. In addition, the mathematical axioms, which are based on field algebra, are declared. In this work we show you in addition: How we check our SFG whether it is a consistent system or not. A signal flow graph can be verified by generating the identity of the signal flow graph itself, illustrated by the inverse signal flow graph (SFG−1). Two signal flow graphs are always generated from one circuit, so that the signal flow diagram already presented in previous sections corresponds to only half of the solution. The other half of the solution is the so-called identity, which represents the (SFG−1). If these two graphs are superposed with one another, so called 1-edges are created at the node points. In Boolean algebra, these 1-edges are given the value 1, whereas this value can be identified with a zero in the field algebra.展开更多
The design method for a low-cost toroidal inductor is proposed as an alternative to power-quality evaluation. The method is based on well-known tools by the engineers in which is presented the relationships that exist...The design method for a low-cost toroidal inductor is proposed as an alternative to power-quality evaluation. The method is based on well-known tools by the engineers in which is presented the relationships that exist between equivalent circuit and transfer function of a toroidal inductor. The proposed design method has been explained with normalized functions based on physical parameters of a toroidal inductor. This work presents the main arguments of the suggested methodology and as demonstration of the design method as function of normalized parameters, is developed a current-signal sensor which has been validated in the laboratory by the EN-50160-2-2 standard to evaluate the power quality in home use loads.展开更多
This paper presents an analysis of dispersion of dynamic biochemical signals in steady flow in a shallow Y-type microfluidic channel. A method is presented to control the flow widths of two steady flows in the Y-type ...This paper presents an analysis of dispersion of dynamic biochemical signals in steady flow in a shallow Y-type microfluidic channel. A method is presented to control the flow widths of two steady flows in the Y-type microchannel from two inlets.The transfer function for the Y-type microchannel is given by solving the governing equation for the Taylor-Aris dispersion in the microchannel. The amplitude-frequency and phase-frequency relations are provided which show that a shallow Y-type microchannel acts as a low-pass filter. The transports of different dynamic biochemical signals are investigated. In comparison with a fully mixing microfluidic channel, the magnitudes of the dynamic signals at the outlets in a Y-type microchannel are much smaller than those in a fully mixing microchannel, which demonstrates that the amplitude attenuation in a Y-type microchannel is larger than that of a fully mixing microchannel due to the transverse molecular diffusion. In order to control the desired signal in a microchannel, the solution of the inverse problem for the channel is also presented.展开更多
On the basis of the pulse source-system model, a convenient and effective method used to evaluate the transfer function of human pulse system has been proposed by using the principle of signal detection and system ana...On the basis of the pulse source-system model, a convenient and effective method used to evaluate the transfer function of human pulse system has been proposed by using the principle of signal detection and system analysis. The experimental results show that the pulse system of the normal pulse has 3 formants; the smooth pulse, 2 formants; the wiry pulse, 4 formants; and the thready pulse, only 1 formant. Formant frequencies reflect the resonance behaviour of the arterial system.展开更多
强干扰区多类噪声时空叠加,对电磁勘探的影响严重且复杂.以往的人工源电磁(Controlled-Source Electromagnetic Method,CSEM)信号处理方法大多针对单道数据进行处理,并未考虑各道之间的相关性,从而产生非必要的误差.为此,在同步观测的...强干扰区多类噪声时空叠加,对电磁勘探的影响严重且复杂.以往的人工源电磁(Controlled-Source Electromagnetic Method,CSEM)信号处理方法大多针对单道数据进行处理,并未考虑各道之间的相关性,从而产生非必要的误差.为此,在同步观测的基础上,本文提出一种基于站间传递函数的CSEM有效信号提取方法.首先,从多域对同步观测的CSEM数据进行质量评价,优选出高信噪比的参考站;其次,基于参考站与测站之间的时域信号方差比(Ratio of variance,ROV)实现测站强干扰噪声的快速识别与定位,采用密度聚类方法(Density-based spatial clustering of applications with noise,DBSCAN)筛选出测站高信噪比数据段,并构建频率域站间传递函数;最后,考虑各道之间的相关性,利用参考站信号与站间传递函数对受强干扰时间段的观测数据进行处理,从而实现了强干扰环境下CSEM有效信号的高精度提取.通过对仿真信号与广域电磁法(Wide Field Electromagnetic Method,WFEM)实测数据的处理,验证了方法的有效性和实用性.结果表明,本文提出的基于站间传递函数的CSEM信噪分离方法不仅考虑了多道同步观测数据之间的相关性,还能在不增加野外工作量的基础上实现对有效信号的高精度提取,方法具有普适性,为CSEM同步阵列数据处理提供了一种快速、可行的解决方案.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 51007068)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20100201120028)+2 种基金the Natural Science Basic Research Plan in Shaanxi Province of China (Grant No. 2012JQ7026)the Fundamental Research Funds for the Central Universities of China (Grant No. 2012jdgz09)the State Key Laboratory of Electrical Insulation and Power Equipment of China (Grant No. EIPE12303)
文摘Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus,the transfer function modeling and analysis of the open-loop Buck converter in a continuous conduction mode（CCM） operation are carried out in this paper.The fractional order small signal model and the corresponding equivalent circuit of the open-loop Buck converter in a CCM operation are presented.The transfer functions from the input voltage to the output voltage,from the input voltage to the inductor current,from the duty cycle to the output voltage,from the duty cycle to the inductor current,and the output impedance of the open-loop Buck converter in CCM operation are derived,and their bode diagrams and step responses are calculated,respectively.It is found that all the derived fractional order transfer functions of the system are influenced by the fractional orders of the inductor and the capacitor.Finally,the realization of the fractional order inductor and the fractional order capacitor is designed,and the corresponding PSIM circuit simulation results of the open-loop Buck converter in CCM operation are given to confirm the correctness of the derivations and the theoretical analysis.
文摘In this work a method called “signal flow graph (SFG)” is presented. A signal-flow graph describes a system by its signal flow by directed and weighted graph;the signals are applied to nodes and functions on edges. The edges of the signal flow graph are small processing units, through which the incoming signals are processed in a certain form. In this case, the result is sent to the outgoing node. The SFG allows a good visual inspection into complex feedback problems. Furthermore such a presentation allows for a clear and unambiguous description of a generating system, for example, a netview. A Signal Flow Graph (SFG) allows a fast and practical network analysis based on a clear data presentation in graphic format of the mathematical linear equations of the circuit. During creation of a SFG the Direct Current-Case (DC-Case) was observed since the correct current and voltage directions was drawn from zero frequency. In addition, the mathematical axioms, which are based on field algebra, are declared. In this work we show you in addition: How we check our SFG whether it is a consistent system or not. A signal flow graph can be verified by generating the identity of the signal flow graph itself, illustrated by the inverse signal flow graph (SFG−1). Two signal flow graphs are always generated from one circuit, so that the signal flow diagram already presented in previous sections corresponds to only half of the solution. The other half of the solution is the so-called identity, which represents the (SFG−1). If these two graphs are superposed with one another, so called 1-edges are created at the node points. In Boolean algebra, these 1-edges are given the value 1, whereas this value can be identified with a zero in the field algebra.
文摘The design method for a low-cost toroidal inductor is proposed as an alternative to power-quality evaluation. The method is based on well-known tools by the engineers in which is presented the relationships that exist between equivalent circuit and transfer function of a toroidal inductor. The proposed design method has been explained with normalized functions based on physical parameters of a toroidal inductor. This work presents the main arguments of the suggested methodology and as demonstration of the design method as function of normalized parameters, is developed a current-signal sensor which has been validated in the laboratory by the EN-50160-2-2 standard to evaluate the power quality in home use loads.
基金National Natural Science Foundation of Chinagrant number:11172060the Fundamental Research Funds for the Central Universities in China
文摘This paper presents an analysis of dispersion of dynamic biochemical signals in steady flow in a shallow Y-type microfluidic channel. A method is presented to control the flow widths of two steady flows in the Y-type microchannel from two inlets.The transfer function for the Y-type microchannel is given by solving the governing equation for the Taylor-Aris dispersion in the microchannel. The amplitude-frequency and phase-frequency relations are provided which show that a shallow Y-type microchannel acts as a low-pass filter. The transports of different dynamic biochemical signals are investigated. In comparison with a fully mixing microfluidic channel, the magnitudes of the dynamic signals at the outlets in a Y-type microchannel are much smaller than those in a fully mixing microchannel, which demonstrates that the amplitude attenuation in a Y-type microchannel is larger than that of a fully mixing microchannel due to the transverse molecular diffusion. In order to control the desired signal in a microchannel, the solution of the inverse problem for the channel is also presented.
文摘On the basis of the pulse source-system model, a convenient and effective method used to evaluate the transfer function of human pulse system has been proposed by using the principle of signal detection and system analysis. The experimental results show that the pulse system of the normal pulse has 3 formants; the smooth pulse, 2 formants; the wiry pulse, 4 formants; and the thready pulse, only 1 formant. Formant frequencies reflect the resonance behaviour of the arterial system.
文摘强干扰区多类噪声时空叠加,对电磁勘探的影响严重且复杂.以往的人工源电磁(Controlled-Source Electromagnetic Method,CSEM)信号处理方法大多针对单道数据进行处理,并未考虑各道之间的相关性,从而产生非必要的误差.为此,在同步观测的基础上,本文提出一种基于站间传递函数的CSEM有效信号提取方法.首先,从多域对同步观测的CSEM数据进行质量评价,优选出高信噪比的参考站;其次,基于参考站与测站之间的时域信号方差比(Ratio of variance,ROV)实现测站强干扰噪声的快速识别与定位,采用密度聚类方法(Density-based spatial clustering of applications with noise,DBSCAN)筛选出测站高信噪比数据段,并构建频率域站间传递函数;最后,考虑各道之间的相关性,利用参考站信号与站间传递函数对受强干扰时间段的观测数据进行处理,从而实现了强干扰环境下CSEM有效信号的高精度提取.通过对仿真信号与广域电磁法(Wide Field Electromagnetic Method,WFEM)实测数据的处理,验证了方法的有效性和实用性.结果表明,本文提出的基于站间传递函数的CSEM信噪分离方法不仅考虑了多道同步观测数据之间的相关性,还能在不增加野外工作量的基础上实现对有效信号的高精度提取,方法具有普适性,为CSEM同步阵列数据处理提供了一种快速、可行的解决方案.
