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Renewable Distributed Generation Models in Three-Phase Load Flow Analysis for Smart Grid Syafii, Syafii; Nor, K. M.
TELKOMNIKA Telecommunication, Computing, Electronics and Control Vol 11, No 4: December 2013
Publisher : Universitas Ahmad Dahlan

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Abstract

The paper presents renewable distributed generation (RDG) models as three-phase resource in load flow computation and analyzes their effect when they are connected in composite networks. The RDG models that have been considered comprise of photovoltaic (PV) and wind turbine generation (WTG). The voltage-controlled node and complex power injection node are used in the models. These improvement models are suitable for smart grid power system analysis. The combination of IEEE transmission and distribution data used to test and analyze the algorithm in solving balanced/unbalanced active systems. The combination of IEEE transmission data and IEEE test feeder are used to test the the algorithm for balanced and unbalanced multi-phase distribution system problem. The simulation results show that by increased number and size of RDG units have improved voltage profile and reduced system losses. 
EFFECT ANALYSIS OF RESIDUAL MAGNETISM AVAILABILITY LEVEL ON THE SUCCESS OF VOLTAGE GENERATION PROCESSES IN SELF-EXCITED INDUCTION GENERATORS Nazir, Refdinal; Syafii, Syafii; Pawawoi, Andi; Akbar, Fajril; Arfan, Yudi
International Journal of Power Electronics and Drive Systems (IJPEDS) Vol 11, No 3: September 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.765 KB) | DOI: 10.11591/ijpeds.v11.i3.pp1211-1219

Abstract

The voltage generation process is a very crucial initial stage for the successful operation of the self-excited induction generator (SEIG). The availability of residual magnetism and the adequacy of excitation capacitor value are factors that determine the success of the voltage generation process on the SEIG. This paper analyzes the effect of the availability of residual magnetism on the rotor's magnetic core. With a simple approach, the terminal voltage on the SEIG can be solved through the intersection between the magnetization curve (Xm) and the excitation curve (Xce). The shape and equation of the magnetization curve will be affected by the availability of residual magnetism. The change in residual magnetism availability will cause a change in the intersection point between the magnetization curve (Xm) and the excitation curve (Xce), which will determine the value of voltage generated by the generator. In this study, Newton Rhapson's method with numerical iteration approach has been used to analyze the effect of changes in the availability of residual magnetism on the success of voltage generation on the SEIG. The analysis results have been shown that the availability of residual magnetism with residual voltage values below 1.04 Volt will cause the failure of the SEIG to generate the terminal voltage at its nominal value. Meanwhile, the availability of residual magnetism in SEIG with residual voltage values above 1.04 Volt, will succeed in generating terminal voltage at its nominal value. For SEIG used as the object of this study, the value of Eres = 1.04 Volt is a critical value of the availability of residual magnetism.
Strategi Pembebanan PLTS Off Grid untuk Peningkatan Kontinuitas Suplai Energi Listrik Syafii, Syafii; Mayura, Yona; Muhardika, Muhardika
Jurnal Rekayasa Elektrika Vol 15, No 3 (2019)
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (713.79 KB) | DOI: 10.17529/jre.v15i3.14793

Abstract

Solar power plants using environmentally friendly technology in the process of harvesting energy from the sun can be a solution to the future electricity crisis so that it has been the most widely developed and reliable alternative. However, the conversion of solar energy depends on the availability and conditions of sunlight. In sunny conditions, the PV system can serve large loads while charging the battery to the maximum. While in cloudy weather conditions or at night, the PV system serves the load and without charge of the battery. The battery will discharge the stored energy until it runs out and the supply to the load will be cut off before the desired time. Therefore, research on PV system loading strategy is needed to increase the amount of electricity from solar energy and maintain the continuity of electricity supply to the load. The load power management strategy follows the conditions of sunny, cloudy, rainy or night time by considering the remaining capacity of the battery that can be used. Load installations are designed to consist of low, medium and high load installations. Simulation results show that the use of PV loading management strategies can increase the operating time of the PV system. When the remaining 15% battery capacity and PLN supply is available, the supply will be switched to PLN. The remaining 15% of PV battery capacity could be used to maintain electricity supply to a low load if the PLN supply interrupted. Thus the use of the charging strategy will increase the supply of electricity from renewable energy and improve the continuity of electricity supply.
EVALUASI PENGGUNAAN AGREGAT EX SUMLILI SEBAGAI MATERIAL LAPIS PONDASI ATAS TERHADAP KERUSAKAN JALAN STRATEGIS NASIONAL / JALUR 40 Setyawan, Ary; Syafii, Syafii
Jurnal Teknik Sipil Vol 1, No 1 (2013): Jurnal Teknik Sipil
Publisher : Jurnal Teknik Sipil

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Abstract

Jalan raya merupakan prasarana transportasi darat yang sangat pentingoleh karena itu kestabilan dari konstuksi jalan bergantung pada sejauh manaperencanaan atau desain dari tipe konstruksi tersebut. Jalan Strategis Nasional /jalur 40 sudah mengalami kerusakan pada lapis pondasi atas pada konstruksiperkerasan ,segmen Sp Tabun – Sp Sikumana dengan panjang 5,200 km denganlebar jalan 4,50 m. Tujuan penelitian ini adalah untuk mengetahui nilai kondisipermukaan perkerasan, penyebab terjadinya kerusakan perkerasan jalan,mengevaluasi kegiatan pemeliharaan yang telah dilaksanakan sebelumnya danmemberikan rekomendasi penyelesaian masalah tersebut.Tahapan penelitian ini meliputi penentuan kondisi perkerasan, Analisakondisi perkerasan jalan dilakukan dengan metode PCI, alternatif perbaikanuntuk lapis pondasi atas (Agregat ’A’) menggunakan material yang sama atauperlukah diganti dengan material yang lain.Hasil analisa PCI pada km.5 + 200 – 10 + 400 diperoleh nilai rata-ratasebesar 21,09 dan termasuk dalam klasifikasi Very poor atau sangat buruksehingga perlu segera dilakukan perbaikan, dan dari hasil pengujianlaboraturium jenis material pada Lapis Pondasi Atas (Agregat ’A’) yang lamaharus diganti dengan marerial lapis pondasi yang baru, berdasarkan hasilpengujian laboraturium material yang dapat digunakan untuk Lapis Pondasi Atas(Agregat ’A’) yaitu untuk batu pecahnya dari quari Ex Sumlili dan materilal tanahputih dari quari Ex Manulai. Setelah dilakukan perbaikan pada Lapis Pondasi atasdengan dua material yang berbeda maka dapat di ketehui nilai rata – rata PCIsetelah perbaikan sebesar 99,64 dan termasuk dalam klasifikasi Excellent atausempurna dalam kategori mantap.Kata kunci : kerusakan perkerasan jalan, nilai PCI , bahan pengganti lapispondasi atas agregat ’A’
PENGEMBANGAN KURIKULUM DAN MEDIA PEMBELAJARAN WAYANG DI TAMAN KANAK-KANAK DI KOTA SEMARANG Syafii, Syafii; Syarir, M Ibnan; syakir, syakir
Abdimas Vol 14, No 2 (2010)
Publisher : Lembaga Penelitian dan Pengabdian Masyarakat (LP2M), Universitas Negeri Semarang

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Abstract

Wayang merupakan salah satu kekayaan budaya bangsa Indonesia yang telah diakui dunia. Namun eksistensinya di negara sendiri semakin tidak diminati terutama oleh para generasi muda. Hal tersebut diduga oleh karena kurangnya dilakukan upaya pembiasaan pada usia dini mereka. Kegiatan ini berupaya untuk mengenalkan wayang pada usia dini, yakni anak usia TK di Kota Semarang, melalui guru sebagai khalayak kegiatan dalam pengembangan kurikulum dan media pembelajaran. Adapun tujuan yang ingin dicapai adalah: 1) Meningkatkan kemampuan guru TK di Kota Semarang dalam mengembangkan kurikulum (materi) pembelajaran wayang, (2)Meningkatkan kemampuan guru-guru TK di Kota Semarang dalam mengembangkan media pembelajaran wayang. Metode yang digunakan dalam kegiatan Pengabdian kepada Masyarakat ini adalah metode ceramah, peragaan, dan latihan pratek yang didukung dengan demonstrasi dan tanya jawab. Berdasarkan pelaksanaan kegiatan pelatihan ini dapat disimpulkan sebagai berikut: 1) Kegiatan pelatihan dapat berjalan sesuai sasaran yang diharapkan tanpa kendala yang berarti. 2) Kegiatan pengabdian ini merupakan salah satu upaya dalam meningkatkan pengetahuan dan keterampilan guru TK dalam mengembangkan kurikulum dan media pembelajaran wayang guna menunjang pembelajaran di Taman Kanak-kanak. 3) Kegiatan ini juga telah memberikan pemahaman pada guru tentang model pembelajaran wayang sebagai alternatif di TK. Dapat disampaikan saransaran: 1) Kepada peserta pelatihan, agar dapat menerapkan di sekolah tempat mengajar masing-masing tentang pengetahuan dan keterampilannya yang didapatkan dalam pelatihan ini. 2) Kepada penyelenggara pendidikan khususnya TK, agar senantiasa berupaya mengembangkan profesionalisme guru dalam pengembangan kurikulum dan media pembelajaran wayang 3) Kepada tim PPM UNNES, agar melakukan kegiatan pelatihan yang sama di wilayah lain sehingga pengetahuan dan keterampilan serupa dapat lebih meluas. 4) Kepada Jurusan Seni Rupa FBS UNNES, agar menindak lanjuti hasil kegiatan ini dalam bentuk penelitian yang secara khusus mengkaji sejauh mana guru dapat membelajarkan wayang dan memanfaatkan media pembelajaran wayang di TK. Kata Kunci: Kurikulum, media pembelajaran, wayang
Komputasi Aliran Daya Optimal Sistem Tenaga Skala Besar dengan Metode Primal Dual Interior Point Syafii, Syafii; Masrul, Ikhwannul Kadri
Jurnal Rekayasa Elektrika Vol 12, No 1 (2016)
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (578.091 KB) | DOI: 10.17529/jre.v12i1.2428

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This paper focuses on the use of Primal Dual Interior Point method in the analysis of optimal power flow. Optimal power flow analysis with Primal Dual Interior Point method then compared with Linear Programming Method using Matpower program. The simulation results show that the computation results of Primal Dual Interior Point similar with Linear Programming Method for total cost of generation and large power generated by each power plant. But in terms of computation time Primal Dual Interior Point method is faster than the method of Linear Programming, especially for large systems. Primal Dual Interior Point method have solved the problem in 40.59 seconds, while Linear Programming method takes longer 239.72 seconds for large-scale system 9241 bus. This is because the settlement PDIP algorithm starts from the starting point x0, which is located within the area of feasible move towards the optimal point, in contrast to the simplex method that moves along the border of the feasible from one extreme point to the other extreme point. Thus Primal Dual Interior Point method have more efficient in solving optimal power flow problem of large-scale power systems.
Asesmen Struktur Gedung Kantor Camat Nongsa Batam Murni, Cahaya; Rahmadi, Agus Parwito; syafii, syafii
Jurnal Teknik Sipil Vol 2, No 2 (2014): Jurnal Teknik Sipil
Publisher : Jurnal Teknik Sipil

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Abstract

Kondisi bangunan gedung Kantor Camat Nongsa Batam mengalami retak struktur yang menyebar pada beberapa bagian struktur bangunan. Retak tersebut secara visual terlihat adanya lendutan pada balok struktur, hal ini dikhawatirkan bangunan sudah tidak aman lagi sesuai fungsinya. Tesis ini bertujuan untuk mengetahui kekuatan pada komponen struktur bangunan serta mengetahui tingkat keamanan struktur pada kondisi eksisting bangunan. Tahapan asesmen yang digunakan yaitu tahapan asesmen awal dan asesmen detail. Tahapan analisis dilakukan terhadap kondisi kekuatan komponen struktur. Proses asesmen dilakukan melalui pengujian lapangan. Pengujian di lapangan menggunakan peralatan Schmidt Rebound Hammer Test untuk mengetahui kuat tekan beton dan mutu beton, Waterpass, Theodolite, , dan meteran untuk pengukuran geometris bangunan. Analisis data menggunakan ETABS V9.7.2. Hasil penelitian yang dilakukan dilapangan menunjukkan bahwa kualitas beton pada bangunan gedung ini bervariasi pada kolom 21.71MPa, balok 29 MPa dan Plat 30.6 MPa. Pada balok lantai dua ( 87%) dan balok lantai tiga (84%) mengalami lendutan yang sudah melebihi nilai batas lendutan yang diijinkan sesuai ketentuan di dalam peraturan yang ada. Nilai interstory drift terbesar 18.637 mm. Perlunya rehabilitasi pada komponen struktur sehingga direkomendasikan adanya perkuatan struktur pada komponen struktur. Kata Kunci : asesmen, pengujian, defleksi, interstory drift, analisis data, komponen struktur, perkuatan.
On Load Characteristic of the New Design Permanent Magnets Reluctance Generator Pawawoi, Andi; Syafii, Syafii
International Journal of Applied Power Engineering (IJAPE) Vol 6, No 3: December 2017
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijape.v6.i3.pp193-198

Abstract

These The new design of a permanent magnet reluctance generator claimed to be able to convert the energy of the permanent magnet is the source of the main field into electrical energy, so that the generator output power can reach 167% compared with the input power axis. In this paper will discuss the characteristics of the generator voltage when under load, pure resistance, inductive load and caThese The new design of a permanent magnet reluctance generator claimed to be able to convert the energy of the permanent magnet is the source of the main field into electrical energy, so that the generator output power can reach 167% compared with the input power axis. In this paper will discuss the characteristics of the generator voltage when under load, pure resistance, inductive load and capacitive load. The results showed that when given a purely resistive load, the terminal voltage tends to be constant, but if given the inductive load, the voltage drop occurs significantly approaching zero voltage at full load current. It is very different when loaded capacitive load. When the generator under load is capacitive, the generator voltage at full load increased by 224.7% from no-load voltage.pacitive load. The results showed that when given a purely resistive load, the terminal voltage tends to be constant, but if given the inductive load, the voltage drop occurs significantly approaching zero voltage at full load current. It is very different when loaded capacitive load. When the generator under load is capacitive, the generator voltage at full load increased by 224.7% from no-load voltage
Sensorless Solar Tracker Based on Sun Position for Maximum Energy Conversion Syafii, Syafii; Nazir, Refdinal; Putra, Muhammad Hadi; Kamsory, Kamsory
Proceeding of the Electrical Engineering Computer Science and Informatics Vol 2: EECSI 2015
Publisher : IAES Indonesia Section

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/eecsi.2.596

Abstract

The performance of solar panels energy conversion is dependent on sunlight it receives. Therefore, it is necessary to design a tracker device that can set the direction of the solar panel always follow the sun position. The two-axis sensorless trackers have developed in this research to maximize energy conversion. Position of solar panel move based on sun position using sunrise and sunset database. By using linear interpolation the sun position in latitute and longitude direction for other time can be obtained during a day. Based on these value the solar panel set its position using two servo motor which drived by Arduino. This technique independent from weather conditions, although cloudy, panel position remains consistent with the maximum illumination when the weather is sunny back later. By this way, the solar panel absorbs maximum sunlight as well as generate maximum electricity.
Sistem Monitoring Online dan Analisa Performansi PLTS Rooftop Terhubung ke Grid PLN Satria, Habib; Syafii, Syafii
Jurnal Rekayasa Elektrika Vol 14, No 2 (2018)
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1307.108 KB) | DOI: 10.17529/jre.v14i2.11141

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This paper presents an online monitoring system and PV system performance analysis under various weather conditions. The PV monitoring system consists of an Arduino sensors circuit, and a design monitor display built using Visual Basic.Net programming. The monitoring system was applied to the 1.25 kW PV system mounted on the roof of the Department of Electrical Engineering, Andalas University. The rooftop PV system is connected to the PLN grid using five units of 250 Wp polycrystalline solar panels and mounted flat in series connected to the load through a 2 kW grid tie inverter. The process of data retrieval of the results of the monitoring took place in real time and displayed in the form of data tables and graphs. The data information of the PV system comes from the sensors connected to the Arduino device which then connected to a PC. Furthermore, data recorded using Visual Basic.Net software converted into Microsoft Excel so it can be analysed further. The PV system performance analysis consists of the synchronisation process, power curve and electrical energy that can be generated by a rooftop PV system. The average solar panels start generating electricity from 7:00 am to 6:00 pm for sunny weather, but for rainy weather, the power of the PV goes down and disconnects early before sunset. The results presented show that the performance of PV systems connected to the PLN network is highly dependent on weather conditions. The monitoring result of power and energy potency can be used as a consideration parameter for a feasibility study of rooftop PV system installed in the tropical area.