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C Akyel - One of the best experts on this subject based on the ideXlab platform.
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Mutual Inductance and magnetic force calculations between thick bitter circular coil of rectangular cross section with inverse radial current and filamentary circular coil with constant azimuthal current
Iet Electric Power Applications, 2017Co-Authors: Slobodan Babic, C AkyelAbstract:In many engineering applications, the coils of different geometrical shapes are used. Usually, these coils (circular, right etc.) are with the constant currents in different directions. In the literature, there are many papers on the calculations of the magnetic fields of the circular coils with the constant azimuthal currents or the calculations of the Mutual Inductance and the magnetic force between them. In some applications, where the high intensity magnetic fields are required the circular metal plates and insulating spacers are used with the inverse radial current. Such configurations form an electromagnet named after its inventor Bitter. In this study, the authors calculate the Mutual Inductance and the magnetic force between the thick Bitter coil of rectangular cross-section with the inverse radial current and the circular filamentary coil with the constant azimuthal current. The semi-analytical and the analytical expressions of these quantities are obtained over complete elliptic integrals of the first and second kind as well as Heuman's lambda function. There is one simple integral which has to be solved numerically. The results of this method are compared by those obtained by the modified filament method for the presented configuration. All results are in an excellent agreement.
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Mutual Inductance and magnetic force calculations for coaxial bitter disk coils pancakes
Iet Science Measurement & Technology, 2016Co-Authors: Slobodan Babic, C AkyelAbstract:Recently Y. Ren and J.T. Conway calculated the Mutual Inductance and the magnetic force between an ordinary coil and a bitter coil or between two bitter coils. The bitter coil is the coil with inverse radial current density. In this study, the authors calculate the Mutual Inductance and the magnetic force between two disk coils (pancakes) with inverse radial current density. This coil configuration with proposed current density seems to be similar to bitter coils. Both calculations give the semi-analytical expressions either for Mutual Inductance or for the magnetic force. Also they derived the self-Inductance for the disk coil with radial current density which is obtained in closed form. The results of this method are compared by those obtained by the modified filament method for the presented configuration.
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new formulas for Mutual Inductance and axial magnetic force between magnetically coupled coils thick circular coil of the rectangular cross section thin disk coil pancake
IEEE Transactions on Magnetics, 2013Co-Authors: Slobodan I Babic, C AkyelAbstract:This paper deals with novel formulas for calculating the Mutual Inductance and the magnetic force between two coaxial coils in air comprising a circular coil of the rectangular cross section and a thin disk coil (pancake). The Mutual Inductance and the magnetic force are expressed over the complete elliptical integrals of the first and second kinds, Heuman's lambda function, and three terms that must be solved numerically. All singular cases have been resolved analytically. We also give another approach as comparative method that is based on the filament method where all conductors are approximated by the set of Maxwell's coils. The expressions are obtained over the complete elliptical integrals of the first and second kinds. These new consistent expressions are accurate and simple for useful applications. All results obtained by different approaches are in excellent agreement.
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new formulas for Mutual Inductance and axial magnetic force between a thin wall solenoid and a thick circular coil of rectangular cross section
IEEE Transactions on Magnetics, 2011Co-Authors: Slobodan I Babic, C Akyel, Frederic Sirois, Guy Lemarquand, V Lemarquand, Romain RavaudAbstract:This paper presents new analytic formulas for determining the Mutual Inductance and the axial magnetic force between two coaxial coils in air, namely a thick circular coil with rectangular cross-section and a thin wall solenoid. The Mutual Inductance and the magnetic force are expressed as complete elliptical integrals of the first and second kind, Heuman's Lambda function and one well-behaved integral that must be solved numerically. All possible singular cases are automatically handled by the proposed formulas. The results of the work presented here have been verified by the filament method and previously published data. The new formulas provide a substantially simple alternative over previously published approaches, which involve either numerical techniques (finite element method, boundary element method, method of moments) or other semianalytic or analytic approaches.
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calculation of the Mutual Inductance and the magnetic force between a thick circular coil of the rectangular cross section and a thin wall solenoid integro differential approach
Progress in Electromagnetics Research B, 2011Co-Authors: Slobodan Babic, C Akyel, Frederic Sirois, Guy Lemarquand, Romain Ravaud, V LemarquandAbstract:Systems that employ stimulating and implantable moni- toring devices utilize inductive links, such as external and implanted coils. The calculation of the Mutual Inductance and the magnetic force between these coils is important for optimizing power transfer. This paper deals with an e-cient and new approach for determining the Mutual Inductance and the magnetic force between two coaxial coils in air. The setup is comprised of a thick circular coil of the rectangular cross section and a thin wall solenoid. We use an integro-difierential approach to calculate these electrical parameters. The Mutual induc- tance and the magnetic force are obtained using the complete elliptic integrals of the flrst and second kind, Heuman's Lambda function and one term that has to be solved numerically. All possible regular and singular cases were solved. The results of the presented work have been verifled with the fllament method and previously published data.
S Babic - One of the best experts on this subject based on the ideXlab platform.
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Mutual Inductance calculation between misalignment coils for wireless power transfer of energy
Progress in Electromagnetics Research M, 2014Co-Authors: S Babic, Cevdet Akyel, Jose Martinez, Bojan BabicAbstract:In this paper we present a detailed theoretical analysis of lateral and angular misalignment effects in RF coils. Radio-frequency (RF) coils are used extensively in the design of implantable devices for transdermal power and data transmission. A design procedure is established to maximize coil coupling for a given configuration to reduce the effects of misalignment on transmission efficiency. Formulas are derived for the Mutual Inductance between all possible coil configurations including the coils of cross section, thin solenoids, pancakes and filamentary circular coils whose axes are laterally and angularly displaced. Coils are in air. In this approach we used the filament method and the Mutual Inductance between filamentary circular coils placed in any desired position. We completely describe all mathematical procedures to define coil positions that lead to relatively easy method for calculating the Mutual Inductance between previously mentioned coils. The practical coils in implantable devices fall into two categories: disk coils (pancakes) and solenoid coils. From the general approach for calculating the Mutual Inductance between coils of rectangular cross section with lateral and angular misalignments the Mutual Inductance between misalignment solenoids and disks will be calculated easily and accurately.
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Mutual Inductance calculation between circular filaments arbitrarily positioned in space alternative to grover s formula
IEEE Transactions on Magnetics, 2010Co-Authors: S Babic, C Akyel, Frederic Sirois, C GirardiAbstract:In this paper, we present the full derivation of a new formula for calculating the Mutual Inductance between inclined circular filaments arbitrarily positioned with respect to each other. Although such a formula was already proposed by Grover more than 50 years ago, the formula presented here is slightly more general and simpler to use, i.e., it involves only a sequential evaluation of expressions and the numerical resolution of a simple numerical integration. We derived the new formula using the method of vector potential, as opposed to Grover's approach, which was based on the Neumann formula. We validated the new formula through a series of examples, which are presented here. Finally, we present the relationship between the two general formulas (i.e., Grover's and our new one) explicitly (Example 12).
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Mutual Inductance calculation between circular coils with lateral and angular misalignment
2009Co-Authors: S Babic, Cevdet Akyel, Mohamedmehdi MahmoudiAbstract:The purpose of this paper is to present a relatively easy approach for the 3D calculation of the Mutual Inductance between circular coils with lateral and angular misalignment. The fllament method and Grover formulas for the Mutual Inductance between fllamentary circular coils with parallel and inclined axes are used in this approach. The semi-analytical formulas of the Mutual induction given in the integral form cover all possible coil conflgurations and lead to very accurate and fast results. This easy and lucid approach is suitable either for micro-coils or large coils so that one does not need to use modern numerical methods such as FEM and BEM frequently employed in such calculations. Computed Mutual-Inductance values obtained by the proposed approach, by the software FastHenry (based on FEM) and by already published data are in a very good agreement. The magnetically coupled coils are important in magnetically controllable devices and sensors, in modern medicine and telemetric systems applied in biomedical engineering (long-term implantable devices such as pacemakers, cochlear implants, deflbrillators, instrumented orthopaedic implants), in conventional medical MRI systems, tokamaks, superconducting coils. In all these applications it is necessary to calculate or measure the Mutual Inductance of magnetically coupled coils (1{ 3). The problem of the accurate and fast calculation of the Mutual Inductance of circular coils in air has a long history in the electrical engineering (4{17). The Mutual Inductance of circular coils can be obtained by analytical, semi-analytical and numerical methods. In this paper, we use Grover formulas expressed over the complete elliptical integrals of the flrst and second kind (4) for calculating the Mutual Inductance between two fllamentary circular coils with parallel and inclined axes. The fllament method (8) is used to replace circular coils of the rectangular cross section (either with lateral or with angular misalignment) by the set of fllamentary circular coils. The simple numerical integration is required to integrate the kernel functions. In this paper, we use Romberg numerical integration and Gaussian numerical integration in singular cases. 2. THEORY 2.1. Circular Coils of the Rectangular Cross Section with Lateral Misalignment Let us take into consideration the system of two non-coaxial circular coils of rectangular cross section with parallel axes (lateral misalignment), (Fig. 1), with N1 and N2, the total number of turns of the windings. It is assumed that the coils are compactly wound and the insulation on the wires is thin, so that the electrical current can be considered uniformly distributed over the whole cross-sections of the winding. The corresponding dimensions of these coils are shown in Fig. 1. The cross-sectional area of the flrst coil I is divided into (2K+1) by (2N+1) cells and the second coil II into (2m + 1) by (2n + 1) cells. Each cell in the flrst coil I contains one fllament, and the current density in the coil cross{section is assumed to be uniform, so that the fllament currents are equal. The same assumption applies to the second coil II (8). Using the fllament method and Grover's Formula (2) (4) for the Mutual Inductance between two circular fllamentary coils with parallel axes, the Mutual Inductance between two circular coils of rectangular cross section with parallel axes is given by,
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Mutual Inductance calculation for non coaxial circular air coils with parallel axes
Progress in Electromagnetics Research-pier, 2009Co-Authors: Cevdet Akyel, S Babic, Mohamedmehdi MahmoudiAbstract:We present a practical and simple method for calculating the Mutual Inductance between two non-coaxial circular coils with parallel axes. All possible circular coils such as coils of rectangular cross section, thin wall solenoids, thin disk coils (pancakes) and circular filamentary coils are taken into consideration. We use Grover’s formula for the Mutual Inductance between two filamentary circular coils with parallel axes. The filament method is applied for all coil combinations, for coils of the rectangular cross section and for thin coils. We consider that the proposed method is very simple, accurate and practical for engineering applications. Computed Mutual Inductance values obtained by the proposed method have been verified by previously published data and the software Fast-Henry. All results are in a very good agreement. This method can be used in various electromagnetic applications such as coil guns, tubular linear motors, transducers, actuators and biomedical implanted sensors.
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new Mutual Inductance calculation of the magnetically coupled coils thin disk coil thin wall solenoid
Journal of Electromagnetic Waves and Applications, 2006Co-Authors: S Babic, C AkyelAbstract:This paper deals with new expressions for calculating the Mutual Inductance between thin wall solenoids and thin disk coils in air. This original method which appears in this mathematical form for the first time may seem complicated but it is exact and fast, even though all expressions are obtained by the complete elliptic integrals of the first and second kind, Neumann's Lambda function and one member that has to be solved numerically. Results of the presented approach are compared to results obtained by the well-known filament method regarding the accuracy and computational cost. Also results of this approach are compared to previously published data These new expressions are accurate and simple for useful applications and they considerably reduce computational time.
S Ron Y Hui - One of the best experts on this subject based on the ideXlab platform.
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front end monitoring of the Mutual Inductance and load resistance in a series series compensated wireless power transfer system
IEEE Transactions on Power Electronics, 2016Co-Authors: Jian Yin, Deyan Lin, Thomas Parisini, S Ron Y HuiAbstract:In this paper, a new method to estimate the Mutual Inductance and load resistance in a series–series compensated wireless power transfer system is presented. Reasonably accurate estimations can be obtained from measurements of the input voltage and current obtained at one operating frequency only. The proposal can be used to dynamically monitor both the coupling relationship between the transmitter and receiver coils and the load conditions without any direct measurement on the receiver side. It can also be used as a simple method to measure the Mutual Inductance of any pair of coupled coils. A novel impedance spectrum analysis method is further presented to show that series–series compensation has special characteristics in its input impedance spectrum. Experimental results with acceptable tolerance are included to show the effectiveness of the proposed method.
Cevdet Akyel - One of the best experts on this subject based on the ideXlab platform.
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Calculation of Mutual Inductance and magnetic force between two thick coaxial Bitter coils of rectangular cross section
IET Electric Power Applications, 2017Co-Authors: Slobodan Babic, Cevdet AkyelAbstract:The Mutual Inductance and magnetic force between coaxial Bitter coils with rectangular cross section were recently calculated by some authors using semi-analytical expressions based on two integrations (Ren et al.) and by using the Bessel function approach (Conway). In this study, these important electrical quantities are calculated using the analytical and semi-analytical expressions based on elliptical integrals of the first and second kinds, Heuman's Lambda function, and two simple integrals with their kernel functions continuous on the whole integration interval. Simple Gaussian numerical integration is used. This method can be applied to calculate the Mutual Inductance and magnetic force between two thin Bitter disk coils (pancakes) as well as between two Bitter coils, where one has a rectangular cross section and the other is a thin disk (pancake). The calculations of the Mutual Inductances and magnetic forces are validated by comparison with values already published in the literature. The presented approach has advantages of high accuracy and low computational time.
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Mutual Inductance calculation between misalignment coils for wireless power transfer of energy
Progress in Electromagnetics Research M, 2014Co-Authors: S Babic, Cevdet Akyel, Jose Martinez, Bojan BabicAbstract:In this paper we present a detailed theoretical analysis of lateral and angular misalignment effects in RF coils. Radio-frequency (RF) coils are used extensively in the design of implantable devices for transdermal power and data transmission. A design procedure is established to maximize coil coupling for a given configuration to reduce the effects of misalignment on transmission efficiency. Formulas are derived for the Mutual Inductance between all possible coil configurations including the coils of cross section, thin solenoids, pancakes and filamentary circular coils whose axes are laterally and angularly displaced. Coils are in air. In this approach we used the filament method and the Mutual Inductance between filamentary circular coils placed in any desired position. We completely describe all mathematical procedures to define coil positions that lead to relatively easy method for calculating the Mutual Inductance between previously mentioned coils. The practical coils in implantable devices fall into two categories: disk coils (pancakes) and solenoid coils. From the general approach for calculating the Mutual Inductance between coils of rectangular cross section with lateral and angular misalignments the Mutual Inductance between misalignment solenoids and disks will be calculated easily and accurately.
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Mutual Inductance calculation between circular coils with lateral and angular misalignment
2009Co-Authors: S Babic, Cevdet Akyel, Mohamedmehdi MahmoudiAbstract:The purpose of this paper is to present a relatively easy approach for the 3D calculation of the Mutual Inductance between circular coils with lateral and angular misalignment. The fllament method and Grover formulas for the Mutual Inductance between fllamentary circular coils with parallel and inclined axes are used in this approach. The semi-analytical formulas of the Mutual induction given in the integral form cover all possible coil conflgurations and lead to very accurate and fast results. This easy and lucid approach is suitable either for micro-coils or large coils so that one does not need to use modern numerical methods such as FEM and BEM frequently employed in such calculations. Computed Mutual-Inductance values obtained by the proposed approach, by the software FastHenry (based on FEM) and by already published data are in a very good agreement. The magnetically coupled coils are important in magnetically controllable devices and sensors, in modern medicine and telemetric systems applied in biomedical engineering (long-term implantable devices such as pacemakers, cochlear implants, deflbrillators, instrumented orthopaedic implants), in conventional medical MRI systems, tokamaks, superconducting coils. In all these applications it is necessary to calculate or measure the Mutual Inductance of magnetically coupled coils (1{ 3). The problem of the accurate and fast calculation of the Mutual Inductance of circular coils in air has a long history in the electrical engineering (4{17). The Mutual Inductance of circular coils can be obtained by analytical, semi-analytical and numerical methods. In this paper, we use Grover formulas expressed over the complete elliptical integrals of the flrst and second kind (4) for calculating the Mutual Inductance between two fllamentary circular coils with parallel and inclined axes. The fllament method (8) is used to replace circular coils of the rectangular cross section (either with lateral or with angular misalignment) by the set of fllamentary circular coils. The simple numerical integration is required to integrate the kernel functions. In this paper, we use Romberg numerical integration and Gaussian numerical integration in singular cases. 2. THEORY 2.1. Circular Coils of the Rectangular Cross Section with Lateral Misalignment Let us take into consideration the system of two non-coaxial circular coils of rectangular cross section with parallel axes (lateral misalignment), (Fig. 1), with N1 and N2, the total number of turns of the windings. It is assumed that the coils are compactly wound and the insulation on the wires is thin, so that the electrical current can be considered uniformly distributed over the whole cross-sections of the winding. The corresponding dimensions of these coils are shown in Fig. 1. The cross-sectional area of the flrst coil I is divided into (2K+1) by (2N+1) cells and the second coil II into (2m + 1) by (2n + 1) cells. Each cell in the flrst coil I contains one fllament, and the current density in the coil cross{section is assumed to be uniform, so that the fllament currents are equal. The same assumption applies to the second coil II (8). Using the fllament method and Grover's Formula (2) (4) for the Mutual Inductance between two circular fllamentary coils with parallel axes, the Mutual Inductance between two circular coils of rectangular cross section with parallel axes is given by,
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Mutual Inductance calculation for non coaxial circular air coils with parallel axes
Progress in Electromagnetics Research-pier, 2009Co-Authors: Cevdet Akyel, S Babic, Mohamedmehdi MahmoudiAbstract:We present a practical and simple method for calculating the Mutual Inductance between two non-coaxial circular coils with parallel axes. All possible circular coils such as coils of rectangular cross section, thin wall solenoids, thin disk coils (pancakes) and circular filamentary coils are taken into consideration. We use Grover’s formula for the Mutual Inductance between two filamentary circular coils with parallel axes. The filament method is applied for all coil combinations, for coils of the rectangular cross section and for thin coils. We consider that the proposed method is very simple, accurate and practical for engineering applications. Computed Mutual Inductance values obtained by the proposed method have been verified by previously published data and the software Fast-Henry. All results are in a very good agreement. This method can be used in various electromagnetic applications such as coil guns, tubular linear motors, transducers, actuators and biomedical implanted sensors.
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VALIDITY CHECK OF Mutual Inductance FORMULAS FOR CIRCULAR FILAMENTS WITH LATERAL AND ANGULAR MISALIGNMENTS
Progress in Electromagnetics Research M, 2009Co-Authors: Slobodan I Babic, Frederic Sirois, Cevdet AkyelAbstract:In this paper we derived the formula for calculating the Mutual Inductance between circular fllaments with lateral and angular misalignment by using the approach of the magnetic vector potential. The results obtained correspond to those of F. W. Grover, although the latter used the general formula given by the Neumann integral instead of a vector potential approach. However, the major purpose of this paper is to clarify some confusion introduced in previous works regarding the Mutual Inductance calculation between thin fllamentary circular coils with parallel axes in air. This problem has been solved by Kim etal. (8) using the magnetic vector potential, but unfortunately it leads to erroneous results, even for slight misalignments of the coils' center axes. This is why we chose to use the approach of the magnetic vector potential to show that, when properly derived, the results must indeed reduce to the well known F. W. Grover's formulas.
Chun Sing Cheng - One of the best experts on this subject based on the ideXlab platform.
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online regulation of receiver side power and estimation of Mutual Inductance in wireless inductive link based on transmitter side electrical information
Applied Power Electronics Conference, 2016Co-Authors: Jeff Powa Chow, Henry Shuhung Chung, Chun Sing ChengAbstract:It is well-known that the power transfer efficiency and the power transmitted over a wireless inductive link are significantly affected by the strength of the magnetic coupling and the spatial displacement between the transmitting and receiving coils. Misalignment between the transmitting and receiving coils is practically unavoidable. In order to control and regulate the receiver-side power, on-the-spot measurement of electrical quantities and establishment of communication link between the transmitter and receiver are typically required. This paper will present an investigation into the use of the transmitter-side electrical information to estimate the Mutual Inductance and regulate the power consumption of the receiver side. The nonlinear characteristics of the diode-bridge rectifier are taken into account in the mathematical formulations. The proposed technique is successfully implemented on a 4W wireless-powered LED driver prototype. Experimental results reveal that the LED power can be regulated within ±25% spatial misalignment over the operating zone. The estimated Mutual Inductance is also found to be in close agreement with the theoretical predictions.
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use of transmitter side electrical information to estimate Mutual Inductance and regulate receiver side power in wireless inductive link
IEEE Transactions on Power Electronics, 2016Co-Authors: Jeff Powa Chow, Henry Shuhung Chung, Chun Sing ChengAbstract:It is well-known that the power transfer efficiency and the power transmitted over a wireless inductive link are significantly affected by the strength of the magnetic coupling and the spatial displacement between the transmitting and receiving coils. Misalignment between the transmitting and receiving coils is practically unavoidable. In order to control and regulate the receiver-side power, on-the-spot measurement of electrical quantities and establishment of communication link between the transmitter and receiver are typically required. This paper will present an investigation into the use of the transmitter-side electrical information to estimate the Mutual Inductance and regulate the power consumption of the receiver side. The nonlinear input voltage–current characteristics of the diode-bridge rectifier, which causes current distortions in the system, are taken into account in the mathematical formulations. The proposed technique is successfully implemented on a 4-W wireless-powered LED driver prototype. Experimental results reveal that the LED power can be regulated within ±25% spatial misalignment over the operating zone. The estimated Mutual Inductance is also found to be in close agreement with the theoretical predictions.
