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"This paper describes about the rarely Newton Raphson formulation for solving the power flowproblem, consist of the injetion 2n current equation written on rectangular coordinate. The Jacobianmatrix has same structure such as admittance matrix knot (Zn x Zn), where each network branchrepresented by block (2 x 2). Execptable for PV bus. Diagonal-of block (2 x 2) from jacobian equationwas proposed as some in admittance matrix knot. The result indicate that the proposed methods forsolving the power flow is faster, its than the conventionally Newton Raphson formulation, expressed inimbalanced power condition which written in polar coordinate."

"ABSTRAKTeknik Tomografi yang berkembang saat ini salah satunya adalah pemanfaatan sinyal akustik untuk menghasilkan citra suatu obyek, dimana sinyal tersebut dihasilkan oleh interaksi medan magnet luar dengan obyek yang berarus listrik, baik arus listriknya di injeksikan dari luar ataupun dibangkitkan sendiri di dalam obyek tersebut. Teknik ini disebut Magnetoacoustic Tomography MAT , yang menggabungkan kontras yang bagus dari teknik Electrical Impedance Tomography EIT dan resolusi spasial yang bagus dari Sonografi.Pada penelitian ini akan dilakukan perancangan piranti keras MAT dengan arus listrik pada sampel di injeksikan dari luar atau sering disebut Magnetoacoustic Tomography with Current Injection MAT-CI . Karena arus listriknya di injeksikan dari luar, maka sebagai sampel pada penelitian ini digunakan obyek yang bersifat konduktif dengan berbagai variasi bentuk dan jenis material. Selain itu arus yang di injeksikan akan divariasikan frekuensinya untuk melihat pengaruh frekuensi terhadap sinyal akustik yang dihasilkan pada beberapa jenis material.Secara keseluruhan dari sistem yang dibuat telah bisa digunakan untuk pengambilan data sinyal ultrasonik pada sistem MAT-CI. Dimana hasil eksperimen juga bisa direkonstruksi menggunakan software MATLAB dengan K-Wave Toolbox-nya, sehingga bisa menggambarkan bentuk sampel yang digunakan.

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ABSTRACTTomography techniques that developed today one of them is the use of acoustic signals to produce an image of an object, where the signal is generated by the interaction of the external magnetic field with an object that has electricity, either the electric current is injected from the outside or self generated within the object. This technique is called Magnetoacoustic Tomography MAT , which combines the excellent contrast of Electrical Impedance Tomography EIT techniques and excellent spatial resolution of Sonography.In this research will be designing MAT hardware with electric current in the sample injected from the outside or often called Magnetoacoustic Tomography with Current Injection MAT CI . Because the electric current is injected from the outside, then as a sample in this study must used objects that are conductive with a variety of shapes and types of materials. In addition, the frequency of the injected current will be varied to see the frequency effect on the acoustic signal generated on some types of materials.Overall of the system that has been created can be used to acquire data of ultrasonic signal on MAT CI system. Where experimental results can also be reconstructed using MATLAB software with its K Wave Toolbox, so it can illustrate the sample form used."

"Motor induksi tiga fasa banyak digunakan oleh dunia industri karena memiliki beberapa keuntungan antara lain motor ini sederhana, murah dan mudah pemeliharaannya. Pada penggunaan motor induksi sering dibutuhkan proses menghentikan putaran motor dengan cepat, terutama aplikasi untuk konveyor. Untuk menghentikan putaran rotor, torsi pengereman diperlukan yang dapat dihasilkan secara mekanik maupun secara elektrik. Pengereman untuk menghentikan putaran motor induksi dapat dirancang secara dinamik, yaitu sistem pengereman yang dilakukan dengan membuat medan magnetik motor stasioner. Keadaan tersebut dilaksanakan dengan menginjeksikan arus DC pada kumparan stator motor induksi tiga fasa setelah hubungan kumparan stator dilepaskan dari sumber tegangan suplai AC. Metode pengereman dinamik memiliki keuntungan antara lain kemudahan pengaturan kecepatan pengereman terhadap motor induksi tiga fasa dan kerugian mekanis dapat dikurangi. Dengan mengaplikasikan pengereman dinamik pada motor induksi tiga fasa didapatkan hasil proses menghentikan putaran motor induksi lebih cepat dibandingkan tanpa pengereman dinamik.

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The Three Phase Induction Motor is common used in industrial technology because they have any advantages, such as simple construction, more cheap, dan easy maintenance. When used, the induction motor ussually needed a process for stop the rotor speed fastest, especially for koneyor aplication. For stop the rotor speed, braking torque needed who can resulting mechanically or electrically. Braking for stop the rotor speed can be builded as dinamic, braking system that making a stationary magnetic field. That condition happen with injecting direct current on stator winding of the three phase induction motor after stator winding connection is cut off from AC voltage supply Dinamic braking method have any advantages, such as easy to setting speed of braking, and also mechanical effect can be minimize. With aplicate dinamic braking on the three phase induction motor, we have that result of the braking process more fastest than without usign dinamic braking."

"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."