In this paper, we present a rigorous full-wave analysis able to estimate exactly the resonant characteristics of stacked high Tc superconducting circular disk microstrip antenna. The superconducting patches are assumed to be embedded in a multilayered substrate containing isotropic and/or uniaxial anisotropic materials (the analysis is valid for an arbitrary number of layers). London’s equations and the two-fluid model of Gorter and Casimir are used in the calculation of the complex surface impedance of the superconducting circular disks. Numerical results are presented for a single layer structure as well as for two stacked circular disks fabricated on a double-layered substrate.

In this paper, we present a rigorous full-wave analysis able to estimate exactly the resonant characteristics of stacked high Tc superconducting circular disk microstrip antenna. The superconducting patches are assumed to be embedded in a multilayered substrate containing isotropic and/or uniaxial anisotropic materials (the analysis is valid for an arbitrary number of layers). London’s equations and the two-fluid model of Gorter and Casimir are used in the calculation of the complex surface impedance of the superconducting circular disks. Numerical results are presented for a single layer structure as well as for two stacked circular disks fabricated on a double-layered substrate.

In this paper, new expressions for the effective radius and fringing capacitance have been derived to predict accurately the resonant frequency of the two-layered circular microstrip patch antenna. These expressions are obtained based on genetic algorithm and the data base is generated using moment method (MOM). The proposed model is very simple, fast, and valid for an entire range of permittivities and thicknesses of two-layered substrate. The present model has been validated by comparing our numerical results obtained for the resonant frequencies with measurements. Finaly, the effect of the two-layered substrate on the resonant charateristics of the circular microstrip patch antenna has been presented.

In this paper, new expressions for the effective radius and fringing capacitance have been derived to predict accurately the resonant frequency of the two-layered circular microstrip patch antenna. These expressions are obtained based on genetic algorithm and the data base is generated using moment method (MOM). The proposed model is very simple, fast, and valid for an entire range of permittivities and thicknesses of two-layered substrate. The present model has been validated by comparing our numerical results obtained for the resonant frequencies with measurements. Finaly, the effect of the two-layered substrate on the resonant charateristics of the circular microstrip patch antenna has been presented.

In this paper, new expressions for the effective radius and fringing capacitance have been derived to predict accurately the resonant frequency of the two-layered circular microstrip patch antenna. These expressions are obtained based on genetic algorithm and the data base is generated using moment method (MOM). The proposed model is very simple, fast, and valid for an entire range of permittivities and thicknesses of two-layered substrate. The present model has been validated by comparing our numerical results obtained for the resonant frequencies with measurements. Finaly, the effect of the two-layered substrate on the resonant charateristics of the circular microstrip patch antenna has been presented.

In this paper, new expressions for the effective radius and fringing capacitance have been derived to predict accurately the resonant frequency of the two-layered circular microstrip patch antenna. These expressions are obtained based on genetic algorithm and the data base is generated using moment method (MOM). The proposed model is very simple, fast, and valid for an entire range of permittivities and thicknesses of two-layered substrate. The present model has been validated by comparing our numerical results obtained for the resonant frequencies with measurements. Finaly, the effect of the two-layered substrate on the resonant charateristics of the circular microstrip patch antenna has been presented.

This paper deals with the robust power control of a grid-connected brushless doubly-fed induction generator (BDFIG) driven by the variable speed wind turbine. With the using of a super twisting algorithm which is a high-order sliding mode controller (HOSMC). This approach guarantees both the dynamic performance and the same robustness as traditional first order (SMC) algorithm and reduces the chattering phenomenon, which is the biggest disadvantage in the implementation of this technique. The developed algorithm relies on the decoupling control by implementing the strategy of oriented grid flux vector control. In order to enhance the desired performances, an attempt is made by controlling the generated stator active and reactive powers in a linear and decoupled manner to ensure the global asymptotical stability, HOSMC approach is implemented. Therefore, an optimal operation of the BDFIG in sub-synchronous operation is used in addition to the stator power flows where the stator power factor is kept in a unity. The suggested method is examined with the Matlab/Simulink software. The performances and the feasibility of the designed control are illustrated by simulation results.

This paper deals with the robust power control of a grid-connected brushless doubly-fed induction generator (BDFIG) driven by the variable speed wind turbine. With the using of a super twisting algorithm which is a high-order sliding mode controller (HOSMC). This approach guarantees both the dynamic performance and the same robustness as traditional first order (SMC) algorithm and reduces the chattering phenomenon, which is the biggest disadvantage in the implementation of this technique. The developed algorithm relies on the decoupling control by implementing the strategy of oriented grid flux vector control. In order to enhance the desired performances, an attempt is made by controlling the generated stator active and reactive powers in a linear and decoupled manner to ensure the global asymptotical stability, HOSMC approach is implemented. Therefore, an optimal operation of the BDFIG in sub-synchronous operation is used in addition to the stator power flows where the stator power factor is kept in a unity. The suggested method is examined with the Matlab/Simulink software. The performances and the feasibility of the designed control are illustrated by simulation results.