Agung Warsito
Jurusan Teknik Elektro, Fakultas Teknik, Universitas Diponegoro Jl. Prof. Sudharto, Tembalang, Semarang, Indonesia

Published : 55 Documents
Articles

BALLAST ELEKTRONIK LAMPU UV BERTOPOLOGI INVERTER SETENGAH JEMBATAN RESONAN LCC FREKUENSI TINGGI Atmaja, Gilang Surya; Warsito, Agung; Karnoto, Karnoto
Transmisi Vol 16, No 2 (2014): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (948.524 KB) | DOI: 10.12777/transmisi.16.2.54-61

Abstract

Abstrak Sinar ultraviolet dapat dengan efektif membunuh segala jenis mikroorganisme, seperti bakteri, virus, jamur dan protozoa. Hal inilah yang membuat lampu ultraviolet dapat digunakan dalam sistem penjernihan udara dan air, seperti pada rumah sakit, kantor, laboratorium, dan lain – lain. Lampu ultraviolet, yang termasuk dalam jenis lampu discharge, membutuhkan komponen ballast untuk dapat menyala. Jenis ballast yang kini semakin marak digunakan yaitu jenis ballast elektronik. Pada penelitian ini dibuat ballast elektronik dengan topologi inverter half bridge resonan LCC frekuensi tinggi. Inverter half bridge menggunakan MOSFET sebagai komponen pensaklarannya. Pengoperasian lampu dengan frekuensi tinggi dapat memperbaiki kinerja lampu. Pemicuan kontrol frekuensi menggunakan IC 4047 dan pengaturan daya keluaran dilakukan dengan mengatur frekuensi pemicuannya sehingga lampu dapat diatur keredupannya.Hasil penelitian ini menunjukkan bahwa ballast eletronik yang dirancang dapat menyalakan lampu pada frekuensi 26 kHz dengan tegangan heating 35,3 V; tegangan igniting 141,4 V dan tegangan running 54,8 V. Ballast elektronik yang dirancang ini tergolong ballast elektronik tipe rapid start. Efisiensi rata – rata ballast ini yaitu 91,8 %.  Daya keluaran ballast dapat diatur dengan mengatur frekuensi kerja sehingga lampu dapat diredupkan. Peredupan dapat dilakukan pada rentang 13,2 W sampai dengan 7,3 W pada frekuensi 25,5 kHz sampai dengan 33,3 kHz.   Kata kunci : ultraviolet, ballast elektronik, inverter     Abstract Ultraviolet light can kill all types of microorganisms, such as bacteria, viruses, fungi and protozoa effectively. This makes ultraviolet light can be used in air and water purification systems, such as in hospitals, offices, laboratories, and others. Ultraviolet lamp, which is included in the type of discharge lamp, needs ballast components to be lit. Types of ballasts which increasingly widespread use now are electronic ballasts.This paper made an electronic ballast with half-bridge resonant inverter topology LCC high frequency. This inverter use MOSFETs as switching components. Operation lamp with high frequency can improve the performance of the lamp. Frequency control is triggered with IC 4047. The setting of power output is done by adjusting frequency so that the lights can be dimmed. The results of this study indicate that electronic ballast turn on the lights at a frequency of 26 kHz with a heating voltage of 35.3 V, igniting voltage of 141.4 V and running voltage of 54.8 V. It can be classified as a rapid start electronic ballast type. Average efficiency of this ballast is 91.8%. The output power can be set by adjusting the ballast operating frequency so that the lights can be dimmed. Dimming can be performed range of frequency 25.5 kHz up to 33.3 kHz and it consumes power of 7.3 W to 13.2 W.   Keyword : ultraviolet, electronic ballast, inverter
Perancangan Pengasutan Bintang – Segitiga dan Pengereman Dinamik pada Motor Induksi 3 Fasa dengan Menggunakan Programmable Logic Controller (PLC) Prakoso, Isna Joko; Warsito, Agung; Sukmadi, Tejo
Transmisi Vol 14, No 1 (2012): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (428.694 KB) | DOI: 10.12777/transmisi.14.1.13-19

Abstract

Three-phase induction motor is the motor of alternating current (AC) is the most widely used and much used by the industry because it has several advantages, among others, this motor is simple, in expensive and easy to maintain and can be directly connected to an AC power source. Besides the advantages of this motor, also has disadvantages. The disadvantage of this induction motor which has a large starting currents and the use of induction motors are often needed to stop the motor rotation quickly, especially for conveyor applications. At this final project, created a system starting star (Y)-triangle (Δ) and the dynamic braking of three phase induction motor using a Programmable Logic Controller (PLC). Where the system is very simple, does not require a lot of support tools and can be applied to any type of three-phase induction motors. Starting of the test results to show that the method starting with Y-Δ has a starting current of 3.59 A. This current is smaller than the nominal starting current induction motor 1 HP is 6.3 A relationship Δ and 3.62 A relationships Y. Starting time is good for the displacement of the star (Y) - triangle (Δ) is 6 seconds, so the starting of induction motors using the star (Y) - triangle (Δ) can reduce the high current flow starting of induction motor starts to operate. For braking, DC injection current is supplied by 1.908 A and the stop time for load 100 W is 1,57 seconds, for load 200 W is 1,38 seconds, and for load 300 W is 0,95 seconds. Time stopped by dynamic braking faster than without dynamic braking. Keywords : Starting star (Y)-triangle (Δ), dynamic braking, three-phase induction motor, Programmable Logic Control (PLC)
PERANCANGAN EXTERNAL LIGHTNING PROTECTION GEDUNG DI KOMPLEK PLTG GORONTALO 100 MW DENGAN METODE ROLLING SPHERE, PROTECTION ANGLE, DAN COLLECTING VOLUME Bakhtiar, Muhamad Marin; Warsito, Agung; Syakur, Abdul
Transmisi Vol 19, No 3 Juli (2017): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1447.659 KB) | DOI: 10.14710/transmisi.19.3.100-107

Abstract

Menurut Badan Meteorologi Klimatologi dan Geofisika tingkat hari guruh pertahun di Indonesia adalah 25 sampai  200. Ini menunjukkan kecenderungan jumlah sambaran petir yang tinggi. Sambaran petir dapat merusak peralatan, merusak bangunan, bahkan korban jiwa. Hal tersebut menimbulkan kerugian yang sangat besar, sehingga dibutuhkan usaha untuk mengurangi resiko kerusakan, yaitu dengan Sistem Proteksi Petir (SPP). Gedung di komplek PLTG Gorontalo 100 MW belum memiliki SPP padahal Gorontalo memiliki hari guruh pertahun mencapai 175,2. Maka, digunakan SPP eksternal (External lightning protection) untuk melindungi gedung dari sambaran petir langsung dengan metode Rolling Sphere, Protection Angle, dan Collecting Volume. Dengan metode tersebut, kita dapat menentukan letak dan jumlah air terminal, down conductor, grounding rod pada tiap gedung hingga seluruh bagian gedung dapat terlindungi dari sambaran petir.  Perhitungan dan perancangan Rolling Sphere dan Protection Angle yang digunakan  berdasarkan IEC 62305-3 sedangkan Collecting Volume berdasarkan IEEE998-2012 standard. Dari penelitian ini dapat diketahui metode Collecting Volume  memiliki area perlindungan terluas dan juga membutuhkan air terminal paling sedikit dibanding dengan metode lainnya. Sehingga, metode Collecting Volume merupakan SPP eksternal terbaik yang dapat melindungi gedung di komplek PLTG Gorontalo 100 MW dari sabaran petir secara langsung.
KINERJA ARRESTER AKIBAT INDUKSI SAMBARAN PETIR Syakur, Abdul; Warsito, Agung
Transmisi Vol 11, No 1 (2009): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (501.351 KB) | DOI: 10.12777/transmisi.11.1.9-15

Abstract

Electricity demand continues to increase so that the required power in a large number of high quality and reliability. Problems in electric power system that occur in transmission and distribution lines that is often of lightning stroke. This is because Indonesia is in the region the equator with a tropical climate and high humidity, so that Indonesia has a number of lightning strikes.In this paper the lightning stroke and lightning arrester performance on distribution lines 20 kV were simulated using EMTP (Electromagnetic Transient Program) for lightning stroke observation.As case study, Mojosongo 1 main feeder 20 kV three phase lines were used. From simulation of lightning stroke 20 kA in By1-61-61E-84-9I  on S phase at 0,1 ms, will experience of increase of voltage on S phase was 1,3054 MV and for R phase and T phase will experience of increase of induced voltage were 0,79539 MV and 0,80484 MV. Then we will see performance of MOV Arrester (Metal Oxide Varistor) in overcoming lightning stroke trouble, where arrester can decrease voltage up to 15,198 kV on S phase, while at R phase and T phase arrester can decrease voltage up to 11,375 kV and 13,616 kV. Keywords: Distribution lines 20 kV, lightning arrester, lightning stroke.
AUDIT ENERGI LISTRIK PADA GEDUNG KAMPUS UNDIP PLEBURAN SEMARANG Salpanio, Ricky; Warsito, Agung; Winardi, Bambang
Transmisi Vol 9, No 2 (2007): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (136.289 KB) | DOI: 10.12777/transmisi.9.2.181-190

Abstract

Konsumsi energi listrik di kampus UNDIP Pleburan mengalami peningkatan setiap tahunnya, sehingga perlu dilakukan perhitungan konsumsi energi listrik ulang guna mengetahui apakah konsumsi energi listriknya masih hemat dan efisien atau tidak. Setelah dilakukan perhitungan konsumsi energi listrik, kemudian mencari alternatif peluang untuk penghematannya. Untuk maksud inilah perlu dilaksanakan kegiatan audit energi listrik di kampus UNDIP Pleburan. Audit energi listrik diawali dengan pengumpulan data historis gedung kampus UNDIP Pleburan. Kemudian menghitung Intensitas Konsumsi Energi (IKE) listrik dari setiap pelanggan yang ada di kampus UNDIP Pleburan. Dari hasil perhitungan IKE tersebut akan diketahui tingkat efisiensi konsumsi energi listrik pada gedung kampus UNDIP Pleburan. Peningkatan efisiensi konsumsi energi listrik di kampus UNDIP Pleburan dapat dilakukan dengan penghentian penggunaan beberapa pelanggan listrik, dimana pelanggan listrik tersebut penggunaannya sudah tidak efisien. Peningkatan efisiensi konsumsi energi listrik di kampus UNDIP Pleburan juga dapat dilakukan dengan penurunan kapasitas pelanggan listrik yang ada di kampus UNDIP Pleburan. Keywords: Audit energi listrik, Intensitas Konsumsi Energi (IKE) listrik, efisiensi, kampus UNDIP Pleburan.
Suplai DC Terpisah untuk Multilevel Inverter Satu Fase Tiga Tingkat Menggunakan Buck Converter Warsito, Agung; Facta, Mochammad; A.W., Donny
Transmisi Vol 10, No 1 (2008): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1171.627 KB) | DOI: 10.12777/transmisi.10.1.10-15

Abstract

DC chopper or DC to DC converter is a power electronics circuit which convert DC voltage to desired variable DC voltage. This paper presents the making of DCChopper in Buck converter type which is used as separated DC power supply for one phase multilevel inverter in three level. This Buck converter produce variable voltage which can be adjusted by duty cycle control in order to meet one phase multilevel inverter need. Duty cycle is obtained by using pulse width modulation technique with constant  frequency range 2 kHz. This separated DC power supply is made from three Buck converter which is consist of three MOSFET as switching components. Triggering signal for MOSFET is produced and controlled by microcontroller AT89S51. This system is made in open loop with one phase multilevel inverter as the load. As a result, this DC chopper is able to supply multilevel inverter with duty cycle varitation for the first and third stage Buck converter is 20%  - 65%, and 50% - 95% for the seccond stage Buck converter.Key words:  buck converter, duty cycle, multi-level inverter, PWM, mikrokontroller
ANALISA PERBAIKAN SUSUT TEKNIS DAN SUSUT TEGANGAN PADA PENYULANG KLS 06 DI GI KALISARI DENGAN MENGGUNAKAN SOFTWARE ETAP 7.5.0 Winardi, Bambang; Warsito, Agung; Kartika, Meigy Restanaswari
Transmisi Vol 17, No 3 Juli (2015): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (563.011 KB) | DOI: 10.12777/transmisi.17.3.135-140

Abstract

Abstrak   Susut daya listrik merupakan persoalan klasik yang dihadapi oleh PLN dan belum dapat sepenuhnya terpecahkan. Permasalahan yang ada di lapangan saat ini adalah tingginya angka susut energi listrik dan susut tegangan yang melebihi standar yang telah ditetapkan. Hal ini merugikan baik dari konsumen listrik itu sendiri maupun dari peruhasahaan dalam hal ini adalah PLN. Untuk mengurangi besarnya susut energi listrik dapat dilakukan secara teknis maupun non teknis. Akan tetapi perbaikan susut secara non teknis sulit dilakukan karena berhubungan dengan manusia dan orang banyak. Sehingga yang dilakukan adalah penekanan susut teknis dan susut tegangan pada jaringan sehingga dapat memperkecil besarnya susut energi listrik. Salah satu cara teknis untuk menguranginya adalah dengan penarikan jaring baru atau pengembangan jaringan. Data exsisting dan penarikan jaring baru disimulasikan menggunakan software ETAP 4.0.0 yang nantinya dapat digunakan dalam menentukan besarnya susut daya dan susut tegangan. Simulasi penekanan susut daya dan susut tegangan menggunakan software ETAP 4.0.0 mempelihatkan perubahan besarnya susut daya dan susut tegangan.   Kata kunci : penekanan susut, software etap 7.5.0, susut teknis, drop tegangan, pengembangan jaringan.   Abstract   Losses of electrical power is a classical problem that is faced by PLN and cannot be completely solved. Nowadays, the problems that exist are the high number of losses and drop voltage that exceeds the established standard. Both the consumers itself or the company of electricity were disadvantage by these problems. To decrease the amount of losses and drop voltage, it can be done by either technical or non-technical way. However, an improvement of losses by non-technical way is difficult to be done because it deals with people and crowds. Then it can be done by the emphasis of technical losses and drop voltage, so that can decrease the amount of electrical power losses. One of technical way to decrease the amount of losses is new distribution feeder development. Existing and new feeder development file were simulated using Etap 4.0.0 software that can be used to determine the amount of technical losses and drop voltage. Emphasis simulation of technical losses and drop voltage using Etap 4.0.0 software shows amount of technical and drop voltage that changed.   Keywords: emphasis losses, software etap 4.0.0, technical losses, voltage drop, feeder development.
PENGGUNAAN FEM (FINITE ELEMENT METHOD) DALAM MEMETAKAN MEDAN LISTRIK PADA PERMUKAAN ISOLATOR JENIS PIN DAN POST 20 KV SERTA UDARA DI SEKITARNYA Warsito, Agung; Facta, M.; Azmi, Safarul
Transmisi VOL 10, NO 4 (2008): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (7425.223 KB) | DOI: 10.12777/transmisi.10.4.172-178

Abstract

Abstract. Electric field is the area which still be influenced electricity from certain electric charge. Based on WHO recommendation in 1990, electric field limits which is allowed at public during 24 hours per day is 5 kV/m. Saluran Udara Tegangan Menengah (SUTM) has big electric field intensity. Therefore, required a study to map the electric field and know the distance that a man is enabled to stay at that electric field limits. The analysis to map the electric field at this final report is by using the Finite Element Method GEM). FEM is a numerical method for solving problems of engineering and mathematical physics. The analysis is assist by using MATLAB 7.0.1 and ANSYS 9.0 as benchmarking prograrn. From the result of simulation, the transformation of electric mast construction at pin type insulator had an effect on the electric field intensity value only at the direction from middle position of conductor upward. The electric mast construction using post type insulator has bigger electric field intensity than the electric mast construction using pin type insulator if evaluated from the same distance. Keywords : electric field, finite element method, and distribution line
PERANCANGAN INVERTER PUSHPULL SEBAGAI CATU DAYA FREKUENSI TINGGI UNTUK RANGKAIAN RESONANSI KUMPARAN TESLA Kurniawan, Sandra Aditya; Warsito, Agung; Facta, Mochammad
Transmisi Vol 16, No 3 (2014): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (996.326 KB) | DOI: 10.12777/transmisi.16.3.114-120

Abstract

Abstrak Salah satu penggunaan rangkaian resonansi adalah untuk menaikkan tegangan, namun rangkaian resonansi tetap memerlukan suatu catu daya arus bolak balik sebagai sumber awal energi listrik.Catu daya tersebut diharapkan dapat diatur besaran tegangan dan frekuensinya agar rangkaian resonansi dapat menghasilkan tergangan yang lebih tinggi. Atas dasar hal diatas, pada Tugas Akhir ini dirancang suatu inverter sebagai alat catu daya arus bolak balik yang dapat diatur frekuensi dan tegangannya.Inverter yang dirancang berupa inverter jenis pushpull yang menggunakan MOSFET sebagai saklar elektronik dan IC TL494 sebagai osilator frekuensi pengontrol pemicuan MOSFET. Rancangan inverter yang dilakukan  juga meliputi perancangan trafo pulsa sebagai isolator listrik antara rangkaian kontrol dan daya. Pengujian dilakukan dengan beban rangkaian resonansi kumparan Tesla untuk mengetahui pengaruh frekuensi dan duty cycle terhadap tegangan disisi beban. Kumparan Tesla memiliki perbandingan 11 : 1400 lilitan. Pengujian dilakukan pada 3 frekuensi, yaitu 100kHz, 114kHz, dan 120kHz.Berdasar hasil pengujian , ketika frekuensi 114kHz didapat tegangan tertinggi, yaitu 3,44 kV, sedangkan pada frekuensi 100kHz, tegangan mencapai 0,7kV, dan untuk frekuensi 120kHz tegangan mencapai 0,5kV. Kata Kunci: resonan, kumparan Tesla, inverter, pushpull.     Abstract   One use of the resonant circuit is to increase voltage. Resonant circuit needs an AC supply as the initial electric source. That source is expected to be equiped with adjustable voltage and frequency in order to produce higher voltage . Based on that reason, in this final assignment, an inverter is as designed alternating current power supply to produce regulated frequency and voltage. The proposed inverter is pushpull inverter that uses MOSFET as electronic switch and IC TL494 MOSFET as a trigger frequency oscillator . The design of the inverter also includes a pulse transformer design as an electrical insulator between the control circuit and the step up pushpull transformer. The test is performed with a Tesla coil resonant circuit as load to know the effect frequency and duty cycle of voltage  at the load side. Tesla coil has a winding ratio of 11: 1400. Test was carried out on 3 frequencies, ie,  100kHz, 114kHz, and 120kHz.The results show that at frequency 114kHz the highest voltage obtained at 3,44 kV, at 100kHz the voltage reaches 0.7 kV, and for frequencies 120kHz the voltage is 0.5 kV. Keyword : resonant, tesla coil , inverter, pushpull.
Perancangan Inverter Dual Conversion Push Pull-Full Bridge pada Aplikasi Fotovoltaik Ariwibowo, Cahyo; Warsito, Agung; Karnoto, Karnoto
Transmisi Vol 12, No 3 (2010): TRANSMISI
Publisher : Departemen Teknik Elektro, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (369.916 KB) | DOI: 10.12777/transmisi.12.3.94-100

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Currently, electric energy is essential for human needs, while for remote areas not all of them powered from PLN. The solution is to use existing energy and transforms it into electrical energy. One of the energy that can be considered is solar energy.Photovoltaic is a device that directly converts solar energy into electricity. To be more efficient, electricity from photovoltaic stored in batteries that can be used at any time during overcast conditions or at night when sunlight does not exist. Most electrical appliances use a standard 220 Volt AC voltage and frequency of 50 Hz, while the electricity generated by photovoltaic is a DC voltage. To get electricity as specified electrical equipment, inverter is used. Inverter is a power electronic device that converts DC voltage into AC voltage.Inverter that was designed can be burdened with incandescent lamp between 100-300 watt with an average efficiency of 63%. Photovoltaic water pump system can supplying 1440 liters of water for every 1 cycle of charging a 65 Ah battery for 52 minutes 18 seconds with an average efficiency of 61%. Keyword :   solar energy, photovoltaic, battery, inverter, water pump