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"Transfer daya nirkabel merupakan sebuah cara baru untuk mengatasi ketidaknyamanan dari sumber listrik dengan kabel. Salah satu cara untuk menyuplai listrik tanpa kabel yaitu menggunakan resonansi kopling elektromagnetik. Cara ini dapat menyuplai listrik ke beban karena adanya medan magnet dan medan listrik di sekitar alat transfer daya nirkabel tersebut. Jadi, perlu diketahui karakteristik medan magnet dan medan listrik dari antena pengirim dan penerima yang akan digunakan pada alat tersebut dan hasilnya apabila dibandingkan dengan standar paparan elektromagnetik. Pada tulisan ini, tiga model antena loop dianalisis yaitu antena berongga, antena pejal, dan antena mikrostrip. Beberapa parameter disimulasikan dengan perangkat lunak berbasis finite integration technique (FIT) yaitu intensitas medan magnet(H-field), medan magnet(B-field), dan intensitas medan listrik(E-field). Hasil simulasi menunjukkan bahwa antena mikrostrip menghasilkan nilai tertinggi pada ketiga parameter yang dianalisis yaitu H-field, B-field, and E-field. Hasil distribusi medan untuk tipe antena yang lain, antena berongga dan pejal, lebih kecil dari pada yang dihasilkan oleh antena mikrostrip. Berdasarkan standar paparan elektromagnetik dari ICNIRP dan IEEE, nilai medan magnet dan medan listrik alat transfer daya nirkabel hasil simulasi masih dibawah standar.Sedangkan pada penerapannya untuk teknologi ruang angkasa, desain dan pengukuran pada jarak 5 mm belum sesuai untuk teknologi ruang angkasa.

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Wireless power transfer is a new way to break inconvenience of wiring power sources. The best way how to supply electric power through wireless system is using the electromagnetic coupled resonance phenomena. It can supply electric power to the load because of the magnetic and electric field that emerge around wireless power transfer device. So, we need to know the characteristic of magnetic and electric field from transmitter and receiver that will be used for the device and see the results based on electromagnetic exposure standard. In this study, three loop model of antennas are investigated, namely a solid coil model, hollow coil model, and microstrip coil model. Some parameters of those models are numerically analyzed using the finite integration technique (FIT) such as magnetic field intensity (H-field), magnetic field (B-field), and electric field intensity (E-field).

The final result shows that microstrip antenna has the highest score in H-field, B-field, and E-field. The field distribution of the others, those are solid coil and hollow coil, are relatively less than that the microstip coil has.Based on electromagnetic exposure like ICNIRP and IEEE, magnetic and electric field of wireless power transfer device are below the standards. Meanwhile, for space aircraft applications, this kind of design and simulation which are measured on 5 mm is unappropriate for space aircraft technology."

"A rapid increase in Sensor markets creates an optical sensor to be a best target for many researchers and scientists for their designing simplicity and easy implementation for a required task. Because of the breadth of optical bio applications, the challenges to design and functioning of an optical sensor for a particular task requires knowledge of optical, material, and environmental properties that affect sensor performance. This undergraduate thesis consists of experiments performed to develop a light intensity and power meter. This can be used to study the interaction between the optical signal and the target, the effect of the environment on propagation of the optical signal, methods to enhance the optical signal, and materials used to generate reliable optical source and to produce sensors with ultra high precision. In optical market several light meters are available to measure luminance values in lux or footcandles. These state of the art light meters measure only the luminance of the area on which the light fall, and displayed over LCD screen. The system designed by the author of this report after performing experiments, follows the state of the art calibration procedure, by taking advantage of the inverse power law that the photo detectors obey to provide user with best accuracy in power and light intensity measurement with graphical user interface. The system provide two parallel sensor data streams feed directly to microcontroller and graphic user interface over serial communication port, hence providing a user with capability to re-modify formulas and other parameters accordingly in GUI. This experiment uses a light dependent resistor (LDR) as a light sensor to build a light intensity and power meter. The instrument uses microcontroller "Arduino" Atmega32 chip with 10 bit ADC resolution as a data measurement processing centre. The results measured by data processing are displayed on LCD screen, and graph is plotted over GUI. With datasheet available on internet, few important parameters can be calculated such as speed response, working frequency, temperature effect and other losses for a microcontroller and sensor used in. The microcontroller is programmed to calculate and calibrate the input LDR value and display the calibrated data output over LCD screen. The system is also designed and programmed to provide serial communication interface for real time data plotting and data saving over various software like matlab, labview, excel, GUI etc."

"Electric Submersible Pump ESP sebagai salah satu metode pengangkatan buatan artificial lift minyak bumi yang dianggap paling efektif dan efisien, semakin banyak diterapkan oleh industri minyak dan gas. Begitupula dengan PT. Medco E P Indonesia yang sedang melakukan perubahan metode artificial lift gas lift menjadi ESP untuk Blok Rimau, Kaji, Sumatera. Dalam proses kerjanya ESP membutuhkan Variable Speed Drive VSD untuk mengendalikan putaran motor submersible sehingga dapat mengatur debit fluida yang dapat diangkat. Namun, saat populasi ESP semakin bertambah, tentunya jumlah dari VSD, sebagai sumber harmonisa beban non-linier , akan semakin bertambah pula. Sehingga kadar harmonisa pada sistem ketenagalistrikan akan semakin mengingkat. Berdasarkan penelitian dalam skripsi ini, penerapan dari transformator penggeser fasa ini mampu menurunkan kadar harmonisa di Kaji, khususnya arus harmonisa orde ke-5 mencapai 61,97, orde ke-7 mencapai 75,67 , orde ke-17 mencapai 90,90, orde ke-19 mencapai 57,14, dan total harmonisa arus mencapai 58 pada titik hubung listrik PCC. Oleh karena itu, transformator penggeser fasa menjadi pilihan metode untuk mengendalikan harmonisa agar dampaknya tidak mengganggu sistem sehingga menurunkan hasil produksi minyak.

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ESP is a one of artificial lift as a considered to be a most effective and efficient methods. The same with PT. Medco E P Indonesia which is doing transformation artificial methods from gas lift to ESP in Rimau Block, Kaji, Sumatera. In the operation system, ESP needs VSD to adjust the speed of induction motors so that can be used to control the flowrate of fluid lifted by the ESP. However, when the population of ESP is increasing, certainly quantity of VSD, as a nonlinear load, is increasing too. Futhermore level of harmonics in electric power system more increasing.

Based on a research in this thesis, implementation of phase shifting transformers can be decreased level of harmonics in Kaji, especially for harmonic current level order 5 up to 61,97, order 7 up to 75,67, order 17 up to 90,90, order 19 up to 57,14, and total harmonic distortion current up to 58 in the point of common coupling PCC. Therefore, phase shifting transformers as a choice methods for handling harmonics so that doesn't make descrease production of oil."