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"Telah dibangun sistem pengendali syringe pump dengan rentang debit 3.2 mL⁄h-202.35 mL⁄h dan high voltage power supply dengan rentang tegangan 0-30 kV untuk sistem electrospinning. Sistem penggerak piston syringe menggunakan linear actuator yang dibangun dari ball screw 1510 dengan penggerak stepper motor. Untuk meningkatkan daya dorong piston syringe, kecepatan stepper motor direduksi dengan gearbox rasio 100:1. Pengaturan debit setiap syringe pump diatur dengan pulsa clock yang diberikan ke driver motor yang frekuensinya dapat diatur dengan persamaan frekuensi versus debit sebesar y=3.9815e^(-5) x-0.0026712. Modul tegangan tinggi AHV24V30KV1MAW dari Analog Technologies membutuhkan suplai tegangan 24 V/2 A yang dapat mengeluarkan output 0-30 kV proporsional dengan input tegangan control 0-5 V. Sistem pengendalian tegangan tinggi digunakan dua metode yaitu metode otomatis dan manual. Tegangan tinggi dan syringe pump digunakan untuk menghasilkan nanofiber menggunakan larutan polimer polyvinyl alcohol (PVA) 15wt%. Proses pengeluaran PVA dengan debit 3.2 mL/h dan tegangan tinggi minimal 10 kV dapat menghasilkan taylor cone dan tumpukan serat di collector.

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A syringe pump control system has been built with a flow rate range of 3.2-202.35 mL/h and a high voltage power supply with a voltage range of 0-30 kV for electrospinning system. Piston of the syringe is driven by a linear actuator built from a 1510 ball screw connected by a stepper motor. To increase the thrust of the syringe piston, the speed of the stepper motor is reduced by a 100:1 ratio gearbox. The flow rate setting of each syringe pump is regulated by clock pulses given to the motor driver whose frequency can be adjusted by the equation of frequency versus discharge of y=3.9815e^(-5) x-0.0026712. The high-voltage module AHV24V30KV1MAW from Analog Technologies requires a 24 V/2 A supply voltage that can output 0-30 kV proportional to the 0 -5 V control voltage input. The high-voltage control system uses two methods, namely automatic and manual methods. High voltage and a syringe pump were used to produce nanofibers using a 15wt% polyvinyl alcohol (PVA) polymer solution. PVA solution is discharged from the syringe with a flow rate of 3.2 mL/h and a high voltage at least 10 kV can produce Taylor cones and piles of fiber in the collector."

"Pompa jarum suntik dianggap sebagai salah satu peralatan medis kritis yang memberikan obat dan cairan dengan dosis terkontrol kepada pasien. Namun, di banyak negara berkembang, pompa jarum suntik konvensional seringkali diimpor  dari luar negeri dengan biaya tinggi. Karena itu  fasilitas kesehatan dengan sumber daya terbatas seringkali  kesulitan untuk mendapatkan dan memelihara perangkat ini, alternatif yang kurang tepat kadang  digunakan sehingga  menempatkan risiko signifikan  bagi pasien yang sensitif.  Untuk mengatasi masalah ini, prototipe pompa jarum suntik yang terjangkau dikembangkan dengan menggunakan teknologi pencetakan 3D. Perangkat ini dirancang dungeon komponen yang dicetak 3D dan komponen yang tersedia secara lokal, sehingga mengurangi ketergantungan pada komponen impor yang mahal. Akurasi volumetrik alat dievaluasi dengan jarum suntik plastik 10 mL menggunakan pendekatan gravimetri. Perangkat diatur untuk mengeluarkan volume air (0,3 - 5 mL) pada variasi laju aliran (1 - 20 mL / menit) dan menghasilkan kesalahan sistematis di bawah 6%.

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Syringe pumps are considered a critical piece of medical equipment that delivers controlled doses of drugs and fluids to patients. However, in many developing countries, conventional syringe pumps are often imported from abroad at a high cost. As health facilities with limited resources often struggle to procure and maintain these devices, less appropriate alternatives are sometimes used, putting sensitive patients at significant risk.  To address this issue, a prototype of an affordable syringe pump was developed using 3D printing technology. The device was designed with 3D printed parts and locally available components, thereby reducing dependence on expensive imported parts. The volumetric accuracy of the device was evaluated with a 10 mL plastic syringe using a gravimetric approach. The device was set to dispense varying volumes of water (0.3 - 5 mL) and resulted in a systematic error below 6%."

"ABSTRACTHigh Voltage measurement based on the electro-optic effect of LiTaOa crystal plate has been developed. This crystal was placed between two parallel plates which more like capacitor arrangement. On the first step, this system was capable only to measure the do voltage from 0 to 1 kV, and the ac voltage from 0 to 0.3 kV. But, by enlarging the spaces in between one side at crystal to one of the plate surface, d, the range of measurement was increased up to 4.8 kV, with d =7 mm."

"Dalam peneliatian ini telah dibuat dan dirancang sistem electrospinning berbasis mikrokontroler. Electrospinning umumnya digunakan untuk membuat nanofibers secara elektrostatik yang kemudian menghasilkan polimer nanofiber dengan diameter dalam skala nm dari larutan polimer yang diberi tegangan tinggi. Jika dibandingkan dengan teknologi konvensional, electrospinning adalah teknik yang serbaguna dan sangat efisien. Untuk dapat menerapkan teknik electrospinning ini, instrumen yang diperlukan adalah microfluidic syringe pump, kolektor, dan tegangan tinggi. Sistem syringe pump dibuat modular dan independent satu sama lain. Setiap syringe pump memiliki motor stepper yang menggerakkan lead screw, yang menggerakkan penyangga untuk piston pada suntikan. Drum kolektor memiliki efek yang signifikan pada produktivitas dan pengaturan nanofibers dan struktur akhir. Kecepatan rotasi atau RPM dari drum kolektor harus dikontrol untuk mendapatkan membran nanofibrous yang optimal. Tegangan tinggi yang diberikan akan menghasilkan peregangan tetesan larutan polimer yang dapat ditingkatkan dengan memberikan tegangan yang lebih tinggi. Pengaturan tegangan yang diterapkan juga merupakan faktor penting dalam teknik electrospinning, oleh karena itu perlu untuk mengontrol tegangan tinggi yang diberikan. Mikrokontroler yang digunakan dalam sistem ini adalah Atmega16. Untuk mengendalikan stepper motor digunakan driver a4988. Komunikasi antara mikrokontroler dan PC menggunakan komunikasi serial dengan baud rate 9600. Fungsi transfer kalibrasi dari microfluidic syringe pump dengan Sistem syringe pump dapat atur hingga 0,0043 mL/detik atau 15480 uL/jam dengan kesalahan Fungsi transfer kalibrasi dari drum kolektor  dengan. Drum kolektor dapat diatur dengan kecepatan maksimum 208 RPM dengan kesalahan.

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This research describes the design development of electrospinning system based on microcontroller. Electrospinning is commonly used to make nanofibers electrostatically which then produces nanofiber polymers with a diameter in the nm scale from a high voltage polymer solution. When compared with conventional technology, electrospinning is a versatile and very efficient technique. To be able to apply this electrospinning technique, the required instruments are microfluidic syringe pump, collector, and high voltage. The syringe pump system is modular and independent of each other. Each pump has a stepper motor that drives the lead screw, which in turn moves the sled (mounted on a linear ball bearing) which pushes (inserts) or pulls (sucks) the syringe. Collectors have a significant effect on the productivity and arrangement of nanofibers and the final structure. The rotation speed or RPM of the drum collector must be controlled to obtain the optimal nanofibrous membranes. The applied voltage will result in stretching of the polymer solution droplets which can be increased by giving a higher voltage. The voltage regulation applied is also an important factor in this electrospinning technique, therefore it is necessary to control the applied high voltage. The microcontroller used in this system is ATmega16. Communication between the microcontroller and PC uses serial communication with a baud rate of 9600. Calibration transfer function of a microfluidic syringe pump  with. The system flow-rate can be set up to 0.0043 mL/second or 15480 uL/hour with error 0,674%. Calibration transfer function of microfluidic syringe pump  with. The collector drum can be set with a maximum speed of 208 RPM with an error of 0.277%."

"This book addresses the very latest research and development issues in high voltage technology and is intended as a reference source for researchers and students in the field, specifically covering developments throughout the past decade. This unique blend of expert authors and comprehensive subject coverage means that this book is ideally suited as a reference source for engineers and academics in the field for years to come."

"Kestabilan tegangan merupakan salah satu syarat sistem operasi tenaga listrik. Tegangan pada sistem tenaga listrik akan mengalami collapse seiring dengan kenaikan beban yang terus menerus hingga mencapai batas maksimumnya. Selain itu terlepasnya unit-unit pembangkit dan sirkit penghantar juga merupakan salah satu penyebab jatuhnya tegangan. Dalam studi kasus ini, tegangan krititis pada Subsistem Bekasi Cibatu dan Kembangan akan dianalisis dengan menggunakan metode kurva PV. Kurva ini menjelaskan hubungan antara daya aktif dan tegangan pada suatu bus. Dengan menaikkan beban, maka nilai tegangan kritis pada pembebanan maksimum dapat diperoleh.Hasil penelitian menunjukkan bahwa susbistem yang diterapkan skenario lepas pembangkit Unit 8 PLTU Suralaya memiliki tegangan kritis terendah sekaligus penurunan tegangan kritis terbesar yaitu subsistem Cibatu dengan tegangan kritis sebesar 423.087 kV atau mengalami penurunan sebesar 5.192 % dari tegangan kritis kondisi normalnya.

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Voltage stability is one of requirements among operation of electrical power system. Voltage on electrical power system will collapse along with continuously rising load until its maximum limit and due to lose of generator unit and conductor circuit.

In this study case, critical voltage at these Subsystem Bekasi Cibatu and Kembangan will be analyzed using PV curve method. The curve explains relationship between active power and voltage on a load bus. Critical voltage value on maximum loading can be yielded when load is increased.

This research resulted that application of lose scenario of PLTU Suralaya Unit 8 has the biggest impact of critical voltage drop at Cibatu subsystem. Critical voltage of Cibatu subsystem is 423.087 kV or its critical voltage decrease to 5.192 % from its critical voltage at normal condition."

"Sistem proteksi sangatlah penting dalam sistem tenaga listrik, terutama untuk kehandalan kerja dan perlindungan pada sistem dalam mesin-mesin listrik. Rele merupakan salah salah satu alat proteksi yang banyak digunakan pada sistem tenaga listrik. Jenis rele bermacam-macam tergantung karakteristik yang dibutuhkan, salah satunya adalah rele jarak dan rele diferesial penghantar. Pada PT. PLN, penggunaan sistem proteksi mutlak diperlukan untuk mendukung kinerja sistem tenaga listrik karena sebagai perusahaan listrik negara, PLN merupakan gardu terdepan dalam pendistribusian listrik di seluruh Indonesia sehingga tentunya diharapkan keberlangsungan sistem listrik tidak terganggu.Pada skripsi ini, penulis akan mengangkat topik tentang konfigurasi proteksi dimana pada sistem transmisi SUTT (Saluran Udara Tegangan Tinggi) di daerah Alam Sutera akan dibangun gardu induk baru sehingga dengan adanya penambahan sistem, konfigurasi sistem proteksi yang lama perlu diperbaharui untuk menyesuaikan dengan sistem yang baru secara keseluruhan. Karena fokus lebih diutamakan pada proteksi utama, maka rele yang akan dibahas pada skripsi ini adalah rele jarak dan rele diferensial penghantar yang biasa digunakan pada SUTT. Untuk melihat koordinasi rele setelah perhitungan, akan digunakan metode scanning untuk melihat hubungan koordinasi antar rele dalam sistem yang baru. Sehingga di dapatkan hasil rekonfigurasi dan pengaruhnya pada sistem sebelumnya.

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Protection system is essential in an electrical power system, especially for the reliability and protection on the system in electric machines. Relay is one of the devices that is widely used in the protection system of electric power. There are various types of relay based on characteristics that are required on system, two of them are distance relay and line differential relay. In PT. PLN, the usage of protection system is undoubtedly needed to support the performance of electrical power systems because their position as main electrical company on the state, PLN is forefront for electrical distribution throughout Indonesia so it is expected that sustainability of the electrical system is not disturbed.In this thesis, the author will discuss the topic of protection system configuration about the high voltage overhead power line of transmision system in the area of Alam Sutera where the new main substation will be built. To adjust this new system as a whole, the old protection system needs to be updated. This thesis will focus in main protection of the system, the relay that will be discussed on this thesis is distance relay and line differential relay which commonly used in high voltage overhead transmission line. For the simulation of distance relay coodination, scanning method will be used to see the relation of coordination of the relay on the new system. Therefore the result can be gotten by reconfiguration and the impact for the previous system."

"The book introduces the reader to the major components of a high voltage system and the different insulating materials applied in particular equipments.During a review of these materials, measurable properties suitable for condition assessment are identified. Analyses are included of some of the insulation fault scenarios that may occur in power equipment.The basic facilities for carrying out tests on the internal and external insulation structures at high and low voltages are described. Tests and measurements according to specifications, on-site requirements and research investigations are considered.Advances in the application of digital techniques for detection and analyses of partial discharges are discussed and methods in use, or under development, for service condition monitoring are described. These include the utilization of new sensors, the solution of online problems associated with noise rejection and the adaptation of artificial intelligence techniques for incipient fault diagnosis.The subject matter of the book is suitable for final year courses in electrical power engineering, short courses in insulation condition assessment and postgraduate programmes. Power system engineers associated with high voltage equipment should find the book of value in relation to fault investigations, maintenance requirements, insulation testing and condition monitoring."