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Abstrak :
Saat ini perkembangan teknologi Wireless Power Transfer (WPT) atau transmisi daya nirkabel semakin meningkat dengan pesat. Penelitian dalam peningkatan efisiensi WPT pun semakin beragam, baik di sisi transmitter maupun di sisi receiver nya. Pada tugas akhir ini, penelitian untuk meningkatkan efisiensi WPT dilakukan di sisi transmitter yaitu pada bagian Power Amplifier (PA). Penambahan terminasi harmonik ketiga pada sisi output PA kelas E konvensional secara efektif mampu menurunkan nilai arus yang mengalir dari drain ke source, sehingga total konsumsi daya rangkaian menjadi lebih rendah. Di sisi lain, modifikasi yang diusulkan mampu meningkatkan power gain secara signifikan sehingga diperoleh peningkatan Power Added Efficiency (PAE). Hasil simulasi desain PA kelas-E dengan terminasi harmonik ketiga pada frekuensi 6,78 MHz menggunakan perangkat lunak Advanced Design Sistem 2020, mampu meningkatkan efisiensi hingga 3,5% dibandingkan PA kelas-E konvensional dan power gain yang dihasilkan bernilai lebih dari 30 dB. Karena keterbatasan alat pengukuran, hasil desain PA pada PCB hanya menghasilkan power output sebesar -3.02 dBm, serta power gain sebesar -27 dB. Perbaikan dan optimasi desain dilakukan untuk memperoleh kondisi optimum desain PA yaitu menggunakan mode bias transistor kelas B pada tegangan VGS 8 volt, dan tegangan VDD sebesar 35 volt. Dengan kondisi tersebut, PA yang diusulkan memiliki nilai power gain sebesar 31.848 dB dan nilai PAE sebesar 26.116%. ......Nowadays, the development of Wireless Power Transfer (WPT) technology or wireless power transmission is increasing rapidly. Research on improving the efficiency of WPT is also increasingly diverse, both on the transmitter and the receiver side. In this final project, the research to improve WPT efficiency is carried out at the transmitter side, i.e., the Power Amplifier (PA). The addition of a third harmonic termination on the output side of the conventional class E PA effectively reduces the drain to the source, so that the total power consumption is decreased. On the other hand, the proposed modification boosts the power gain so that the Power Added Efficiency (PAE) increases simultaneously. The simulation of class-E PA with third harmonic termination at a frequency of 6.78 MHz increases the PAE by 3.5% compared to conventional E-class PA and the power gain increase by 6.23 dB. Due to the limitations of measurement tools, the PA design on the PCB only produces an output power of -3.02 dBm and a power gain of -27 dB. Design improvement and optimization are carried out to obtain the optimum conditions for the PA design by using class B transistor bias mode at VGS of 8 V and VDD of 35 V. Under these conditions, the proposed PA has a power gain of 31,848 dB and a PAE of 26,116%.

Abstrak :
This book investigates the utilization of harmonics in the permanent magnet (PM) or rotor shape to improve the torque density of PM brushless AC machines including three-phase inner rotor and outer rotor machines, five-phase machines, dual three-phase machines, linear machines, by means of analytical, finite element analyses, and as well as experimental validation. The torque density can be improved while the torque ripple remains low in PM shaping utilizing the 3rd harmonic. In this book, the analytical expression of output torque is derived for PM machines with rotor shape using the 3rd harmonic, and then the optimal 3rd harmonic for maximizing torque is analytically obtained. The book compares the PM shape in surface-mounted PM (SPM) machines and the rotor lamination shape in interior PM (IPM) machines utilizing the 3rd harmonic, and it becomes clear that their shaping methods and amount of torque improvement are different. In a five-phase PM machine, the 3rd harmonic can be utilized in both the current waveform and PM shapes to further improve the output torque. For the dual three-phase SPM machines without deteriorating the torque more than 30% when the optimal 3rd harmonic into both the current and PM shape are injected. The harmonics in airgap flux density have significant influence on the cogging torque, stator iron flux distribution, and radial force between the rotor and stator. These effects has been investigated as well in this book.

Abstrak :
This monograph deals with theoretical aspects and numerical simulations of the interaction of electromagnetic fields with nonlinear materials. It focuses in particular on media with nonlinear polarization properties. It addresses the direct problem of nonlinear Electrodynamics, that is to understand the nonlinear behavior in the induced polarization and to analyze or even to control its impact on the propagation of electromagnetic fields in the matter. The book gives a comprehensive presentation of the results obtained by the authors during the last decade and put those findings in a broader, unified context and extends them in several directions. It is divided into eight chapters and three appendices. Chapter 1 starts from the Maxwell’s equations and develops a wave propagation theory in plate-like media with nonlinear polarizability. In chapter 2 a theoretical framework in terms of weak solutions is given in order to prove the existence and uniqueness of a solution of the semilinear boundary-value problem derived in the first chapter. Chapter 3 presents a different approach to the solvability theory of the reduced frequency-domain model. Here the boundary-value problem is reduced to finding solutions of a system of one-dimensional nonlinear Hammerstein integral equations. Chapter 4 describes an approach to the spectral analysis of the linearized system of integral equations. Chapters 5 and 6 are devoted to the numerical approximation of the solutions of the corresponding mathematical models. Chapter 7 contains detailed descriptions, discussions and evaluations of the numerical experiments. Finally, chapter 8 gives a summary of the results and an outlook for future work.