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Prerit Pramod - One of the best experts on this subject based on the ideXlab platform.
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modeling of mutually coupled switched reluctance motors based on Net Flux method
IEEE Transactions on Industry Applications, 2020Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal Husain, Prerit PramodAbstract:Modeling and accurate estimation of mutual Flux in switched reluctance motors are complex due to interphase Flux interactions, magNetic saturation, and harmonics. The mutual Flux contributes significantly toward torque production of mutually coupled switched reluctance motors (MCSRMs); therefore, their accurate modeling directly influences the control design. In this article, a Net-Flux-based machine model is proposed to model MCSRMs. The model utilizes dual-phase excitation and multiphase excitation methods to generate the Flux lookup tables from the finite-element model of the MCSRM. The modeling process is simple, as it does not require the segregation of the self- and mutual Flux components, and machine performance can be predicted accurately using the Net Flux. The proposed modeling method is validated by implementing it for a fully pitched and concentrated-wound MCSRM and evaluating accuracy against the finite-element method. Details of the developed model are presented along with its comparison with existing methods. A prototype of a fully pitched MCSRM has been built, and the model is validated experimentally. Results show that the proposed model has excellent accuracy even under saturated operating conditions.
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Predictive Current Control of Mutually Coupled Switched Reluctance Motors Using Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit PramodAbstract:This work presents a fixed switching frequency predictive current controller for Mutually Coupled Switched Reluctance Machines (MCSRMs). For high performance applications requiring high precision torque control, it is necessary to have high bandwidth current regulators. This can be satisfied by using a digital deadbeat control strategy. Since the controller is model based, it is essential to estimate the mutual Flux accurately. This can be challenging in the case of reluctance machines because of the magNetic non-linearity, especially in the saturation region. In order to have an accurate reference current tracking, the controller is developed on the machine model which is based on the Net Flux Method (NFM). Dynamic simulations are carried out in Matlab/Simulink to control a 12/8, 1 HP MCSRM. The results are presented and compared with the performance of proportional integral (PI) controller.
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Small Signal Model of Mutually Coupled Switched Reluctance Motors Based on Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit Pramod, Ashfanoor KabirAbstract:In this work, a small signal model is developed for Mutually Coupled Switched Reluctance Machines (MCSRMs) based on Net Flux Method (NFM) that facilitates the development of the motor current controller utilizing established controller development resources. This method expedites the modeling, as well as the controller process as separate calculations of the self and mutual Flux as a function of rotor position and phase currents are not required. Using NFM, the MCSRM can be represented in terms of a single Net phase incremental inductance which further simplifies the controller design procedure. The modeling is complemented with the complete design procedure of a proportional-integrator (PI) controller. Dynamic simulations of a 3 phase, 1 HP, tooth wound, MCSRM drive system is carried out in Matlab and Simulink and results are presented. A prototype of a 150 W, fully pitched MCSRM has been built and preliminary experimental results are presented.
Siddharth Mehta - One of the best experts on this subject based on the ideXlab platform.
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modeling of mutually coupled switched reluctance motors based on Net Flux method
IEEE Transactions on Industry Applications, 2020Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal Husain, Prerit PramodAbstract:Modeling and accurate estimation of mutual Flux in switched reluctance motors are complex due to interphase Flux interactions, magNetic saturation, and harmonics. The mutual Flux contributes significantly toward torque production of mutually coupled switched reluctance motors (MCSRMs); therefore, their accurate modeling directly influences the control design. In this article, a Net-Flux-based machine model is proposed to model MCSRMs. The model utilizes dual-phase excitation and multiphase excitation methods to generate the Flux lookup tables from the finite-element model of the MCSRM. The modeling process is simple, as it does not require the segregation of the self- and mutual Flux components, and machine performance can be predicted accurately using the Net Flux. The proposed modeling method is validated by implementing it for a fully pitched and concentrated-wound MCSRM and evaluating accuracy against the finite-element method. Details of the developed model are presented along with its comparison with existing methods. A prototype of a fully pitched MCSRM has been built, and the model is validated experimentally. Results show that the proposed model has excellent accuracy even under saturated operating conditions.
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Predictive Current Control of Mutually Coupled Switched Reluctance Motors Using Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit PramodAbstract:This work presents a fixed switching frequency predictive current controller for Mutually Coupled Switched Reluctance Machines (MCSRMs). For high performance applications requiring high precision torque control, it is necessary to have high bandwidth current regulators. This can be satisfied by using a digital deadbeat control strategy. Since the controller is model based, it is essential to estimate the mutual Flux accurately. This can be challenging in the case of reluctance machines because of the magNetic non-linearity, especially in the saturation region. In order to have an accurate reference current tracking, the controller is developed on the machine model which is based on the Net Flux Method (NFM). Dynamic simulations are carried out in Matlab/Simulink to control a 12/8, 1 HP MCSRM. The results are presented and compared with the performance of proportional integral (PI) controller.
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Small Signal Model of Mutually Coupled Switched Reluctance Motors Based on Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit Pramod, Ashfanoor KabirAbstract:In this work, a small signal model is developed for Mutually Coupled Switched Reluctance Machines (MCSRMs) based on Net Flux Method (NFM) that facilitates the development of the motor current controller utilizing established controller development resources. This method expedites the modeling, as well as the controller process as separate calculations of the self and mutual Flux as a function of rotor position and phase currents are not required. Using NFM, the MCSRM can be represented in terms of a single Net phase incremental inductance which further simplifies the controller design procedure. The modeling is complemented with the complete design procedure of a proportional-integrator (PI) controller. Dynamic simulations of a 3 phase, 1 HP, tooth wound, MCSRM drive system is carried out in Matlab and Simulink and results are presented. A prototype of a 150 W, fully pitched MCSRM has been built and preliminary experimental results are presented.
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Decoupled Modeling of Mutually Coupled SRM Based on Net Flux Method
2018 IEEE Transportation Electrification Conference and Expo (ITEC), 2018Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal HusainAbstract:This work presents a novel method to model mutually coupled switched reluctance machines (MCSRMs). The model uses Flux look-up tables (LUTs) generated from finite element analysis (FEA) based on dual phase excitations. The modeling process is simplified by removing the segregation of the self and mutual Flux components. The performance can be predicted using only one 2D LUT. The Net Flux approach makes the model universal and can be applied to any dual phase excited SRM. Details of the model implementation are described along with its performance with comparison against existing methods and FEA. Results show that the proposed model has improved accuracy, especially in the saturated operating conditions, making it more suitable for high performance applications.
Ashfanoor Kabir - One of the best experts on this subject based on the ideXlab platform.
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modeling of mutually coupled switched reluctance motors based on Net Flux method
IEEE Transactions on Industry Applications, 2020Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal Husain, Prerit PramodAbstract:Modeling and accurate estimation of mutual Flux in switched reluctance motors are complex due to interphase Flux interactions, magNetic saturation, and harmonics. The mutual Flux contributes significantly toward torque production of mutually coupled switched reluctance motors (MCSRMs); therefore, their accurate modeling directly influences the control design. In this article, a Net-Flux-based machine model is proposed to model MCSRMs. The model utilizes dual-phase excitation and multiphase excitation methods to generate the Flux lookup tables from the finite-element model of the MCSRM. The modeling process is simple, as it does not require the segregation of the self- and mutual Flux components, and machine performance can be predicted accurately using the Net Flux. The proposed modeling method is validated by implementing it for a fully pitched and concentrated-wound MCSRM and evaluating accuracy against the finite-element method. Details of the developed model are presented along with its comparison with existing methods. A prototype of a fully pitched MCSRM has been built, and the model is validated experimentally. Results show that the proposed model has excellent accuracy even under saturated operating conditions.
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Small Signal Model of Mutually Coupled Switched Reluctance Motors Based on Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit Pramod, Ashfanoor KabirAbstract:In this work, a small signal model is developed for Mutually Coupled Switched Reluctance Machines (MCSRMs) based on Net Flux Method (NFM) that facilitates the development of the motor current controller utilizing established controller development resources. This method expedites the modeling, as well as the controller process as separate calculations of the self and mutual Flux as a function of rotor position and phase currents are not required. Using NFM, the MCSRM can be represented in terms of a single Net phase incremental inductance which further simplifies the controller design procedure. The modeling is complemented with the complete design procedure of a proportional-integrator (PI) controller. Dynamic simulations of a 3 phase, 1 HP, tooth wound, MCSRM drive system is carried out in Matlab and Simulink and results are presented. A prototype of a 150 W, fully pitched MCSRM has been built and preliminary experimental results are presented.
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Decoupled Modeling of Mutually Coupled SRM Based on Net Flux Method
2018 IEEE Transportation Electrification Conference and Expo (ITEC), 2018Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal HusainAbstract:This work presents a novel method to model mutually coupled switched reluctance machines (MCSRMs). The model uses Flux look-up tables (LUTs) generated from finite element analysis (FEA) based on dual phase excitations. The modeling process is simplified by removing the segregation of the self and mutual Flux components. The performance can be predicted using only one 2D LUT. The Net Flux approach makes the model universal and can be applied to any dual phase excited SRM. Details of the model implementation are described along with its performance with comparison against existing methods and FEA. Results show that the proposed model has improved accuracy, especially in the saturated operating conditions, making it more suitable for high performance applications.
Sebastien Fromang - One of the best experts on this subject based on the ideXlab platform.
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MHD simulations of the magNetorotational instability in a shearing box with zero Net Flux: the case Pm = 4
Astronomy and Astrophysics, 2010Co-Authors: Sebastien FromangAbstract:Aims. This letter investigates the transport properties of MHD turbulence induced by the magNetorotational instability at large Reynolds numbers Re when the magNetic Prandtl number Pm is larger than unity. Methods. Three MHD simulations of the magNetorotational instability (MRI) in the unstratified shearing box with zero Net Flux are presented. These simulations are performed with the code Zeus and consider the evolution of the rate of angular momentum transport as Re is gradually increased from 3125 to 12 500 while simultaneously keeping Pm = 4. To ensure that the small scale features of the flow are well resolved, the resolution varies from 128 cells per disk scaleheight to 512 cells per scaleheight. The latter constitutes the highest resolution of an MRI turbulence simulation to date. Results. The rate of angular momentum transport, measured using the α parameter, depends only very weakly on the Reynolds number: α is found to be about 7 × 10- 3 with variations around this mean value bounded by 15% in all simulations. There is no systematic evolution with Re. For the best resolved model, the kiNetic energy power spectrum tentatively displays a power-law range with an exponent -3/2, while the magNetic energy is found to shift to smaller and smaller scales as the magNetic Reynolds number increases. A couple of different diagnostics both suggest a well-defined injection length of a fraction of a scaleheight. Conclusions. The results presented in this letter are consistent with the MRI being able to transport angular momentum efficiently at large Reynolds numbers when Pm = 4 in unstratified zero Net Flux shearing boxes.
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mhd simulations of the magNetorotational instability in a shearing box with zero Net Flux the case pm 4
Astronomy and Astrophysics, 2010Co-Authors: Sebastien FromangAbstract:Aims. This letter investigates the transport properties of MHD turbulence induced by the magNetorotational instability at large Reynolds numbers Re when the magNetic Prandtl number Pm is larger than unity. Methods. Three MHD simulations of the magNetorotational instability (MRI) in the unstratified shearing box with zero Net Flux are presented. These simulations are performed with the code Zeus and consider the evolution of the rate of angular momentum transport as Re is gradually increased from 3125 to 12 500 while simultaneously keeping Pm = 4. To ensure that the small scale features of the flow are well resolved, the resolution varies from 128 cells per disk scaleheight to 512 cells per scaleheight. The latter constitutes the highest resolution of an MRI turbulence simulation to date. Results. The rate of angular momentum transport, measured using the α parameter, depends only very weakly on the Reynolds number: α is found to be about 7 × 10- 3 with variations around this mean value bounded by 15% in all simulations. There is no systematic evolution with Re. For the best resolved model, the kiNetic energy power spectrum tentatively displays a power-law range with an exponent -3/2, while the magNetic energy is found to shift to smaller and smaller scales as the magNetic Reynolds number increases. A couple of different diagnostics both suggest a well-defined injection length of a fraction of a scaleheight. Conclusions. The results presented in this letter are consistent with the MRI being able to transport angular momentum efficiently at large Reynolds numbers when Pm = 4 in unstratified zero Net Flux shearing boxes.
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mhd simulations of the magNetorotational instability in a shearing box with zero Net Flux the case pm 4
arXiv: High Energy Astrophysical Phenomena, 2010Co-Authors: Sebastien FromangAbstract:This letter investigates the transport properties of MHD turbulence induced by the magNetorotational instability at large Reynolds numbers Re when the magNetic Prandtl number Pm is larger than unity. Three MHD simulations of the magNetorotational instability (MRI) in the unstratified shearing box with zero Net Flux are presented. These simulations are performed with the code Zeus and consider the evolution of the rate of angular momentum transport as Re is gradually increased from 3125 to 12500 while simultaneously keeping Pm=4. To ensure that the small scale features of the flow are well resolved, the resolution varies from 128 cells per disk scaleheight to 512 cells per scaleheight. The latter constitutes the highest resolution of an MRI turbulence simulation to date. The rate of angular momentum transport, measured using the alpha parameter, depends only very weakly on the Reynolds number: alpha is found to be about 0.007 with variations around this mean value bounded by 15% in all simulations. There is no systematic evolution with Re. For the best resolved model, the kiNetic energy power spectrum tentatively displays a power-law range with an exponent -3/2, while the magNetic energy is found to shift to smaller and smaller scales as the magNetic Reynolds number increases. A couple of different diagnostics both suggest a well-defined injection length of a fraction of a scaleheight. The results presented in this letter are consistent with the MRI being able to transport angular momentum efficiently at large Reynolds numbers when Pm=4 in unstratified zero Net Flux shearing boxes.
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MHD simulations of the magNetorotational instability in a shearing box with zero Net Flux II. The effect of transport coefficients
Astronomy & Astrophysics, 2007Co-Authors: Sebastien Fromang, J C B Papaloizou, Geoffroy Lesur, T. HeinemannAbstract:Aims. We study the influence of the choice of transport coefficients (viscosity and resistivity) on MHD turbulence driven by the magNetorotational instability (MRI) in accretion disks. Methods. We follow the methodology described in Paper I: we adopt an unstratified shearing box model and focus on the case where the Net vertical magNetic Flux threading the box vanishes. For the most part we use the operator split code ZEUS, including explicit transport coefficients in the calculations. However, we also compare our results with those obtained using other algorithms (NIRVANA, the PENCIL code and a spectral code) to demonstrate both the convergence of our results and their independence of the numerical scheme. Results. We find that small scale dissipation affects the saturated state of MHD turbulence. In agreement with recent similar numerical simulations done in the presence of a Net vertical magNetic Flux, we find that turbulent activity (measured by the rate of angular momentum transport) is an increasing function of the magNetic Prandtl number Pm for all values of the Reynolds number Re that we investigated. We also found that turbulence disappears when the Prandtl number falls below a critical value Pmc that is apparently a decreasing function of Re. For the limited region of parameter space that can be probed with current computational resources, we always obtained Pmc > 1. Conclusions. We conclude that the magnitudes of the transport coefficients are important in determining the properties of MHD turbulence in numerical simulations in the shearing box with zero Net Flux, at least for Reynolds numbers and magNetic Prandtl numbers that are such that transport is not dominated by numerical effects and thus can be probed using current computational resources.
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MHD simulations of the magNetorotational instability in a shearing box with zero Net Flux - I. The issue of convergence
Astronomy & Astrophysics, 2007Co-Authors: Sebastien Fromang, J C B PapaloizouAbstract:Aims. We study the properties of MHD turbulence driven by the magNetorotational instability (MRI) in accretion disks. To do this we perform a series of numerical simulations for which the resolution is gradually increased. Methods. We adopt the local shearing box model and focus on the special case for which the initial magNetic Flux threading the disk vanishes. We employ the finite difference code ZEUS to evolve the ideal MHD equations. Results. Performing a set of numerical simulations in a fixed computational domain with increasing resolution, we demonstrate that turbulent activity decreases as resolution increases. The highest resolution considered is 256 grid cells per scale height. We quantify the turbulent activity by measuring the rate of angular momentum transport through evaluating the standard α parameter. We find α = 0.004 when $(N_x,N_y,N_z) = (64,100,64)$, α = 0.002 when $(N_x,N_y,N_z) = (128,200,128)$ and α = 0.001 when $(N_x,N_y,N_z) = (256,400,256)$. This steady decline is an indication that numerical dissipation, occurring at the grid scale is an important determinant of the saturated form of the MHD turbulence. Analysing the results in Fourier space, we demonstrate that this is due to the MRI forcing significant flow energy all the way down to the grid dissipation scale. We also use our results to study the properties of the numerical dissipation in ZEUS. Its amplitude is characterised by the magnitude of an effective magNetic Reynolds number $\rm Re_{M}$ which increases from 10 4 to 10 5 as the number of grid points is increased from 64 to 256 per scale height. Conclusions. The simulations we have carried out do not produce results that are independent of the numerical dissipation scale, even at the highest resolution studied. Thus it is important to use physical dissipation, both viscous and resistive, and to quantify contributions from numerical effects, when performing numerical simulations of MHD turbulence with zero Net Flux in accretion disks at the resolutions normally considered.
Iqbal Husain - One of the best experts on this subject based on the ideXlab platform.
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modeling of mutually coupled switched reluctance motors based on Net Flux method
IEEE Transactions on Industry Applications, 2020Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal Husain, Prerit PramodAbstract:Modeling and accurate estimation of mutual Flux in switched reluctance motors are complex due to interphase Flux interactions, magNetic saturation, and harmonics. The mutual Flux contributes significantly toward torque production of mutually coupled switched reluctance motors (MCSRMs); therefore, their accurate modeling directly influences the control design. In this article, a Net-Flux-based machine model is proposed to model MCSRMs. The model utilizes dual-phase excitation and multiphase excitation methods to generate the Flux lookup tables from the finite-element model of the MCSRM. The modeling process is simple, as it does not require the segregation of the self- and mutual Flux components, and machine performance can be predicted accurately using the Net Flux. The proposed modeling method is validated by implementing it for a fully pitched and concentrated-wound MCSRM and evaluating accuracy against the finite-element method. Details of the developed model are presented along with its comparison with existing methods. A prototype of a fully pitched MCSRM has been built, and the model is validated experimentally. Results show that the proposed model has excellent accuracy even under saturated operating conditions.
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Predictive Current Control of Mutually Coupled Switched Reluctance Motors Using Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit PramodAbstract:This work presents a fixed switching frequency predictive current controller for Mutually Coupled Switched Reluctance Machines (MCSRMs). For high performance applications requiring high precision torque control, it is necessary to have high bandwidth current regulators. This can be satisfied by using a digital deadbeat control strategy. Since the controller is model based, it is essential to estimate the mutual Flux accurately. This can be challenging in the case of reluctance machines because of the magNetic non-linearity, especially in the saturation region. In order to have an accurate reference current tracking, the controller is developed on the machine model which is based on the Net Flux Method (NFM). Dynamic simulations are carried out in Matlab/Simulink to control a 12/8, 1 HP MCSRM. The results are presented and compared with the performance of proportional integral (PI) controller.
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Small Signal Model of Mutually Coupled Switched Reluctance Motors Based on Net Flux Method
2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019Co-Authors: Siddharth Mehta, Iqbal Husain, Prerit Pramod, Ashfanoor KabirAbstract:In this work, a small signal model is developed for Mutually Coupled Switched Reluctance Machines (MCSRMs) based on Net Flux Method (NFM) that facilitates the development of the motor current controller utilizing established controller development resources. This method expedites the modeling, as well as the controller process as separate calculations of the self and mutual Flux as a function of rotor position and phase currents are not required. Using NFM, the MCSRM can be represented in terms of a single Net phase incremental inductance which further simplifies the controller design procedure. The modeling is complemented with the complete design procedure of a proportional-integrator (PI) controller. Dynamic simulations of a 3 phase, 1 HP, tooth wound, MCSRM drive system is carried out in Matlab and Simulink and results are presented. A prototype of a 150 W, fully pitched MCSRM has been built and preliminary experimental results are presented.
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Decoupled Modeling of Mutually Coupled SRM Based on Net Flux Method
2018 IEEE Transportation Electrification Conference and Expo (ITEC), 2018Co-Authors: Siddharth Mehta, Ashfanoor Kabir, Iqbal HusainAbstract:This work presents a novel method to model mutually coupled switched reluctance machines (MCSRMs). The model uses Flux look-up tables (LUTs) generated from finite element analysis (FEA) based on dual phase excitations. The modeling process is simplified by removing the segregation of the self and mutual Flux components. The performance can be predicted using only one 2D LUT. The Net Flux approach makes the model universal and can be applied to any dual phase excited SRM. Details of the model implementation are described along with its performance with comparison against existing methods and FEA. Results show that the proposed model has improved accuracy, especially in the saturated operating conditions, making it more suitable for high performance applications.