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Jian Sun - One of the best experts on this subject based on the ideXlab platform.
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Input Impedance modeling of multipulse rectifiers by double-fourier series method
2010 IEEE Energy Conversion Congress and Exposition, 2010Co-Authors: Zhonghui Bing, Jian SunAbstract:Rectifier Input Impedance models are required for stability analysis of ac power systems with significant amount of rectification loads. Such stability analysis is particularly important for mobile and autonomous systems, such as aircraft and ship power systems, where high-power, multipulse rectifiers often dominates the loads. Averaging techniques can be applied to develop Input Impedance models for PWM rectifiers. To model the Input Impedance of line-frequency rectifiers, a direct linearization technique was developed recently and has been applied to model direct multipulse rectifiers without using inter-phase transformers. This paper extends the previous work and uses double-Fourier series method to develop describing (mapping) functions for the rectifier bridge. The double-Fourier method overcomes the limitations of conventional Fourier analysis which requires the perturbation frequency to be commensurable with the line fundamental frequency. The method is also applied to model the Input Impedance of multipulse rectifiers with interphase transformers. Analytical Input Impedance models are presented and validated by numerical simulation and experimental results.
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Input Impedance modeling of multipulse rectifiers by harmonic linearization
IEEE Transactions on Power Electronics, 2009Co-Authors: Jian Sun, Zhonghui Bing, Kamiar J. KarimiAbstract:Multipulse rectifiers are used in large industrial drives, aircraft, electric ships, and other systems, where limits on harmonic currents prohibit the use of conventional three-phase, six-pulse rectifiers. The large power rating of these rectifiers and the dynamic nature of the loads often necessitate the study of their dynamic interactions with the source, which can lead to system stability and power quality problems if not properly designed. This paper presents Input Impedance models for multipulse rectifiers that can be used for such system stability and dynamic power quality analysis. The modeling method is based on the concept of harmonic linearization and makes use of analytical mapping functions that describe voltage and current transfer through multiphase diode rectifiers. Input Impedance models are developed first for general N-phase rectifiers, and then combined with a model of the phase-shifting transformer to define the three-phase Input Impedance. Magnetizing inductance and line commutation due to transformer leakage inductance are also considered. Details of the modeling method are presented using an 18-pulse rectifier as example, and experimental measurement results are also presented to validate the models.
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low frequency Input Impedance modeling of boost single phase pfc converters
IEEE Transactions on Power Electronics, 2007Co-Authors: Min Chen, Jian SunAbstract:Input Impedance models of boost single-phase power factor correction converters suitable for predicting small-signal Input characteristics below the line fundamental frequency are presented in this paper. Existing low-frequency Input Impedance models based on double averaging predicts Input current responses to perturbations in the amplitude of the Input voltage. It is shown in this paper that such Impedance models do not conform to the standard definition of Impedance, and, hence, cannot be used in conjunction with the source output Impedance to study system interactions based on the Nyquist stability criterion, as traditionally done in dc power systems. A new Input Impedance model that overcomes this problem is developed by using the method of harmonic balance. The new model conforms to the standard definition of Impedance and predicts Input current responses to superimposed Input harmonic voltages. Numerical simulation and experimental results are presented to validate the proposed model. Mathematical relationship between the two types of models are also presented.
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Input Impedance analysis of single-phase PFC converters
IEEE Transactions on Power Electronics, 2005Co-Authors: Jian SunAbstract:The Input Impedance of single-phase boost power factor corrected (PFC) AC-DC converters is modeled and analyzed in this paper. A large-signal model is presented for the Input Impedance which overcomes the limitations of traditional piece-wise linearized models. The model is valid at frequencies ranging from the crossover frequency of the output voltage loop to half the switching frequency of the converter. Experimental results from a boost single-phase PFC converter are provided to validate the model. Input characteristics of typical boost PFC converters, such as Input Impedance dipping, leading phase of the Input current, and responses to distorted Input voltages are studied by using the model. A simple compensation technique to reduce the dipping in the Input Impedance, thereby improving converter performance and minimizing the potential for undesirable interactions with the Input filter or the ac source, is also presented.
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Input Impedance analysis of single-phase PFC converters
Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition 2003. APEC '03., 1Co-Authors: Jian SunAbstract:Input Impedance of single-phase boost power factor corrected (PFC) AC-DC converters is modeled and analyzed in this paper. A large-signal model is presented for the Input Impedance which overcomes the limitations of traditional piecewise linearized models. The model is valid at frequencies ranging from the crossover frequency of the output voltage loop to half the switching frequency of the converter. Experimental results from a boost single-phase PFC converter are provided to validate the model. Input characteristics of typical boost PFC converter designs, such as Input Impedance dipping, leading phase of the Input current, and responses to distorted lines are studied by using the model. A simple compensation technique to reduce the dipping in the Input Impedance thereby improving converter performance and minimizing the potential for undesirable interactions with the Input EMI filter is also presented.
Kamiar J. Karimi - One of the best experts on this subject based on the ideXlab platform.
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Input Impedance modeling of multipulse rectifiers by harmonic linearization
IEEE Transactions on Power Electronics, 2009Co-Authors: Jian Sun, Zhonghui Bing, Kamiar J. KarimiAbstract:Multipulse rectifiers are used in large industrial drives, aircraft, electric ships, and other systems, where limits on harmonic currents prohibit the use of conventional three-phase, six-pulse rectifiers. The large power rating of these rectifiers and the dynamic nature of the loads often necessitate the study of their dynamic interactions with the source, which can lead to system stability and power quality problems if not properly designed. This paper presents Input Impedance models for multipulse rectifiers that can be used for such system stability and dynamic power quality analysis. The modeling method is based on the concept of harmonic linearization and makes use of analytical mapping functions that describe voltage and current transfer through multiphase diode rectifiers. Input Impedance models are developed first for general N-phase rectifiers, and then combined with a model of the phase-shifting transformer to define the three-phase Input Impedance. Magnetizing inductance and line commutation due to transformer leakage inductance are also considered. Details of the modeling method are presented using an 18-pulse rectifier as example, and experimental measurement results are also presented to validate the models.
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Input Impedance Modeling and Analysis of Line-Commutated Rectifiers
IEEE Transactions on Power Electronics, 2009Co-Authors: Zhonghui Bing, Kamiar J. KarimiAbstract:This paper presents the modeling and analysis of small-signal Input Impedance for line-commutated rectifiers. The recently developed Impedance mapping method, which has been applied to single-phase rectifiers with sinusoidal line Inputs, is generalized to single-phase rectifiers with distorted lines as well as three-phase rectifiers. The modeling method assumes known Impedance of the circuit on the dc side of the rectifier bridge (including its output filter and the load), and determines the corresponding ac Input Impedance by using a current and voltage mapping function that describes the operation of the rectifier bridge in the frequency domain. In this approach, closed-form analytical expressions are derived for the ac Input Impedance as functions of the dc circuit Impedance. The resulting models are intended for stability analysis and design of large ac power systems involving significant number of rectification loads, such as more-electric aircraft power systems and microgrids. Detailed derivation of the models is presented in this paper. Numerical simulation and experimental measurement results are also presented to validate the developed models.
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small signal Input Impedance modeling of line frequency rectifiers
IEEE Transactions on Aerospace and Electronic Systems, 2008Co-Authors: Kamiar J. KarimiAbstract:This paper presents a systematic method for modeling small-signal Input Impedance of line-frequency AC-DC converters. The objective is to develop proper models that can be used for stability analysis of AC power systems with significant DC loads powered by such converters. The proposed modeling method uses harmonic linearization and Fourier analysis techniques to describe the current and voltage mapping process through the converter switching circuit. The voltage and current mapping relations are then combined to give an Impedance mapping model which converts the Impedance of any circuit or system connected to the DC output of converter into a corresponding small-signal Input Impedance of the converter at the AC side. Similar relations can be used to map the AC source Impedance into the DC side to give the equivalent dc source Impedance for stability analysis of the DC subsystem. This paper focuses on the basic principle of the Impedance mapping method and uses a single-phase diode rectifier circuit to demonstrate the modeling process. The resulting ac Input Impedance model is validated by detailed circuit simulation as well as experimental measurements.
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Input Impedance Modeling and Analysis of Line-Commutated Rectifiers
2007 IEEE Power Electronics Specialists Conference, 2007Co-Authors: Zhonghui Bing, Kamiar J. KarimiAbstract:This paper presents the modeling and analysis of small-signal Input Impedance for line-commutated rectifiers. The recently developed Impedance mapping method, which has been applied to single-phase rectifiers with sinusoidal line Inputs, is generalized to single-phase rectifiers with distorted lines as well as three-phase rectifiers. The modeling method assumes known Impedance of the circuit on the dc side of the rectifier bridge (including its output filter and the load), and determines the corresponding ac Input Impedance by using a current and voltage mapping function which describes the operation of the rectifier bridge in the frequency domain. In this approach, closed-form analytical expressions are derived for the ac Input Impedance as functions of the dc circuit Impedance. The resulting models are intended for stability analysis and design of large ac power systems involving significant number of rectification loads, such as more-electric aircraft power systems and microgrids. Detailed derivation of the models is presented in this paper. Numerical simulation and experimental measurement results are also presented to validate the derived models.
Zhonghui Bing - One of the best experts on this subject based on the ideXlab platform.
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Input Impedance modeling of multipulse rectifiers by double-fourier series method
2010 IEEE Energy Conversion Congress and Exposition, 2010Co-Authors: Zhonghui Bing, Jian SunAbstract:Rectifier Input Impedance models are required for stability analysis of ac power systems with significant amount of rectification loads. Such stability analysis is particularly important for mobile and autonomous systems, such as aircraft and ship power systems, where high-power, multipulse rectifiers often dominates the loads. Averaging techniques can be applied to develop Input Impedance models for PWM rectifiers. To model the Input Impedance of line-frequency rectifiers, a direct linearization technique was developed recently and has been applied to model direct multipulse rectifiers without using inter-phase transformers. This paper extends the previous work and uses double-Fourier series method to develop describing (mapping) functions for the rectifier bridge. The double-Fourier method overcomes the limitations of conventional Fourier analysis which requires the perturbation frequency to be commensurable with the line fundamental frequency. The method is also applied to model the Input Impedance of multipulse rectifiers with interphase transformers. Analytical Input Impedance models are presented and validated by numerical simulation and experimental results.
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Input Impedance modeling of multipulse rectifiers by harmonic linearization
IEEE Transactions on Power Electronics, 2009Co-Authors: Jian Sun, Zhonghui Bing, Kamiar J. KarimiAbstract:Multipulse rectifiers are used in large industrial drives, aircraft, electric ships, and other systems, where limits on harmonic currents prohibit the use of conventional three-phase, six-pulse rectifiers. The large power rating of these rectifiers and the dynamic nature of the loads often necessitate the study of their dynamic interactions with the source, which can lead to system stability and power quality problems if not properly designed. This paper presents Input Impedance models for multipulse rectifiers that can be used for such system stability and dynamic power quality analysis. The modeling method is based on the concept of harmonic linearization and makes use of analytical mapping functions that describe voltage and current transfer through multiphase diode rectifiers. Input Impedance models are developed first for general N-phase rectifiers, and then combined with a model of the phase-shifting transformer to define the three-phase Input Impedance. Magnetizing inductance and line commutation due to transformer leakage inductance are also considered. Details of the modeling method are presented using an 18-pulse rectifier as example, and experimental measurement results are also presented to validate the models.
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Input Impedance Modeling and Analysis of Line-Commutated Rectifiers
IEEE Transactions on Power Electronics, 2009Co-Authors: Zhonghui Bing, Kamiar J. KarimiAbstract:This paper presents the modeling and analysis of small-signal Input Impedance for line-commutated rectifiers. The recently developed Impedance mapping method, which has been applied to single-phase rectifiers with sinusoidal line Inputs, is generalized to single-phase rectifiers with distorted lines as well as three-phase rectifiers. The modeling method assumes known Impedance of the circuit on the dc side of the rectifier bridge (including its output filter and the load), and determines the corresponding ac Input Impedance by using a current and voltage mapping function that describes the operation of the rectifier bridge in the frequency domain. In this approach, closed-form analytical expressions are derived for the ac Input Impedance as functions of the dc circuit Impedance. The resulting models are intended for stability analysis and design of large ac power systems involving significant number of rectification loads, such as more-electric aircraft power systems and microgrids. Detailed derivation of the models is presented in this paper. Numerical simulation and experimental measurement results are also presented to validate the developed models.
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Input Impedance Modeling and Analysis of Line-Commutated Rectifiers
2007 IEEE Power Electronics Specialists Conference, 2007Co-Authors: Zhonghui Bing, Kamiar J. KarimiAbstract:This paper presents the modeling and analysis of small-signal Input Impedance for line-commutated rectifiers. The recently developed Impedance mapping method, which has been applied to single-phase rectifiers with sinusoidal line Inputs, is generalized to single-phase rectifiers with distorted lines as well as three-phase rectifiers. The modeling method assumes known Impedance of the circuit on the dc side of the rectifier bridge (including its output filter and the load), and determines the corresponding ac Input Impedance by using a current and voltage mapping function which describes the operation of the rectifier bridge in the frequency domain. In this approach, closed-form analytical expressions are derived for the ac Input Impedance as functions of the dc circuit Impedance. The resulting models are intended for stability analysis and design of large ac power systems involving significant number of rectification loads, such as more-electric aircraft power systems and microgrids. Detailed derivation of the models is presented in this paper. Numerical simulation and experimental measurement results are also presented to validate the derived models.
Min Chen - One of the best experts on this subject based on the ideXlab platform.
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low frequency Input Impedance modeling of boost single phase pfc converters
IEEE Transactions on Power Electronics, 2007Co-Authors: Min Chen, Jian SunAbstract:Input Impedance models of boost single-phase power factor correction converters suitable for predicting small-signal Input characteristics below the line fundamental frequency are presented in this paper. Existing low-frequency Input Impedance models based on double averaging predicts Input current responses to perturbations in the amplitude of the Input voltage. It is shown in this paper that such Impedance models do not conform to the standard definition of Impedance, and, hence, cannot be used in conjunction with the source output Impedance to study system interactions based on the Nyquist stability criterion, as traditionally done in dc power systems. A new Input Impedance model that overcomes this problem is developed by using the method of harmonic balance. The new model conforms to the standard definition of Impedance and predicts Input current responses to superimposed Input harmonic voltages. Numerical simulation and experimental results are presented to validate the proposed model. Mathematical relationship between the two types of models are also presented.
Kerim Guney - One of the best experts on this subject based on the ideXlab platform.
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SIMPLE MODEL FOR THE Input Impedance OF RECTANGULAR MICROSTRIP ANTENNA
Pamukkale University Journal of Engineering Sciences, 2011Co-Authors: Celal Yildiz, Kerim GuneyAbstract:A very simple model for the Input Impedance of a coax-fed rectangular microstrip patch antenna is presented. Itis based on the cavity model and the equivalent resonant circuits. The theoretical Input Impedance resultsobtained from this model are in good agreement with the experimental results available in the literature. Thismodel is well suited for computer-aided design (CAD).
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Input Impedance of an equilateral triangular microstrip antenna
Proceedings of MELECON '94. Mediterranean Electrotechnical Conference, 1Co-Authors: Kerim GuneyAbstract:The Input Impedance of an equilateral triangular microstrip antenna is obtained from the magnetic wall cavity model with a new effective side length and effective relative dielectric constant. The theoretical Input Impedance and resonant frequency results obtained from the cavity model with this new effective side length and effective relative dielectric constant are in very good agreement with experimental results available in the literature. >
