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This paper presents a hybrid photovoltaic (PV)-diesel management system performance analysis considering weather conditions. The system is designed to operate based on charging current, battery capacity, and loading current. During charging current is decreased but the battery capacity is high, and the PV system remains supplied for low and medium loading current. When the charging current is lowered and the battery capacity is in the middle, the PV system still supplies for low loading current. However, when the charging current decreases and the battery voltage decreased below 22.3 volts, the supply instantly switches to the diesel generator. The charge current is calculated by subtracting the PV current from the load current. A real-time clock is implemented as a timer to guarantee that there is no repetitive switching throughout the night when charging from the panel is missing. The system works automatically through microcontroller control during the day for 9 hours. The improvement that has been obtained is to overcome the problem of repeated switching processes by limiting the transfer process back to PV when sunlight is not available.

Kegiatan perencanaan pengembangan sistem informasi untuk pengelolaan Taman Bacaan Masyarakat (TBM) Karang Putih dengan mitra kegiatan ini adalah Taman Bacaan Masyarakat (TBM) Karang Putih. Permasalahan utama dari TBM dimana belum memiliki sistem pengelolaan yang berbasis teknologi informasi untuk mendukung aktifitas kegiatan sehari–hari. Untuk itu dilakukan pengembangan aplikasi yang berbasis teknologi informasi untuk pengelolaan aktivitas di TBM Karang Putih. Pengembangan aplikasi sistem yang berbasis teknologi informasi ini bertujuan untuk pengelolaan aktivitas di TBM Karang Putih secara efektif dan efisien. Adapun manfaat dari adanya aplikasi sistem informasi ini selain untuk membantu pengelolaan aktivitas sehari – hari di Taman Bacaan Masyarakat (TBM) Karang Putih juga mampu memberikan dampak pada peningkatan proses pembelajaran, peningkatan kesadaran dan kemampuan penggunaan teknologi informasi di Taman Bacaan Masyarakat (TBM) Karang Putih Kelurahan Batu Gadang Kecamatan Lubuk Kilangan Kota Padang. Adapun metoda pelaksanaan kegiatan ini akan difokuskan pada perencanaan pengembangan aplikasi sistem informasi untuk membantu pengelolaan aktivitas di Taman Bacaan Masyarakat (TBM) Karang Putih.

Energi listrik adalah salah satu kebutuhan utama bagi usaha pertanian hidroponik. Mereka butuh untuk mengalirkan nutrisi tanaman melalui air secara terus-menerus menggunakan pompa. Jika sumber energi listrik terputus, maka akan menyebabkan tanaman tidak tumbuh sempurna. Oleh karena itu, pada kegiatan ini dilakukan penerapan sel surya sebagai energi listrik alternatif pada mitra pengabdian Alfi Hidroponik. Kegiatan dilaksanakan dengan merancang kebutuhan sel surya pada usaha hidroponik. Batrai Aki 40 Ah dapat menjadi sumber energi listrik bagi usaha mitra yang kebutuhan dayanya 85 watt selama minimal 10 jam. Selain penerapan sel surya, pada pengabdian ini juga dikembangkan beberapa sensor untuk memonitor suhu dan kelembaban lahan pertahian. Kegiatan ini dapat menjawab kebutuhan mitra dan masih diperlukan penerapan teknologi lainnya pada usaha hidroponik untuk optimalisasi produksi mitra.

This journal describes the design and analysis of the response of a single controller and cascade direct current type of Automatic Voltage Regulator (AVR) system. The direct current AVR system is represented form of a transfer function. For single and cascade controllers, it is designed using a parallel architecture using MATLAB software with predetermined design criteria. The types of controllers used consist of Proportional Differential (PD), Proportional Integral (PI), Proportional Integral Differential (PID), Proportional Differential with First Order Filters in the Differential Section (PDF) and Proportional Integral Differentials with First Order Filters in the Differential Section(PIDF). For the transition analysis, the observed parameters consist of rise time, peak time, steady state time, maximum pass value and peak value. The results of the analysis show that the controllers that meet the design criteria are Proportional Differential (PD) controllers and Proportional Differential controllers with First Order Filters in Differential Sections (PDF) for single controllers and cascade controllers. For a single controller, the value of the Proportional constant (Kp) is 0.6280 and the value of the Differential constant (KD) is 0.1710 for the Proportional Differential (PD) controller. Proportional constant value (Kp) is 0.6130, Differential constant value (KD) is 0.1710 and filter constant value (Tf) is 0.0009 for Proportional Differential controller with First Order Filter in Differential Section (PDF). Cascade controllers and Proportional Differential (PD) controllers, the Proportional constant (Kp) is 1.7300 and the Differential constant (KD) is 0.0242 for the inner circle (C2). Outer ring controller (C1), the proportional constant (Kp) is 179,000 and the Differential constant (KD) is 2.4600. Cascade controllers and Proportional Differential controller types with First Order Filters in the Differential Section (PDF), the Proportional constant (Kp) value is 1.5900, the Differential constant (KD) value is 0.0246, the filter constant value (Tf) is 0.0018 for the inner circumference (C2 ). For the outer ring controller (C1), the Proportional constant (Kp) value is 134,0000, the Differential constant (KD) value is 2.2900 and the filter constant value (Tf) is 0.00008.

This paper presents the economic feasibility of hybrid microgrid power system for three remote islands of Sumatra, Indonesia. The microgrid system simulated and analysed using Homer Pro software. Optimization results showed that the combination of photovoltaic (PV), diesel generation (G) and batteries (Batt) for microgrid power system in Mandeh and Lagundri Island area were the most economical configuration. Meanwhile, for Mentawai area, the combination of PV, Wind Turbine (WT), G, Batt was the most optimal since it has higher wind speed then the other two areas. The Mandeh area has the highest solar radiation compared to the other two areas, resulting in the lowest CoE of $0.096/kWh as well as the lowest investment and operational costs. For the fixed PV 100 kW scenario, the optimal configuration is obtained with 86 kW supplied by WT for the Lagundri location, and 67 kW supplied by WT for the Mentawai area, while the WT installation area is not recommended for Mandeh location. The power management analysis showed that the average and patterns of weather parameters including solar radiation and wind speed effect both PV and Wind electrical power production.

This journal discusses the design and analysis of the transfer response of the direct cuurent type of Automatic Voltage Regulator (AVR) system with 2 degrees of freedom controller. Direct current type of the AVR system is represented in the form of transfer function. For 2 degrees of freedom controllers are designed using a parallel architecture with the help of Matlab software using predefined design criteria. The types of controllers used consist of Proportional Differential (PD), Proportional Integral (PI), Proportional Integral Differential (PID), Proportional Differential with First Order Filters in the Differential Section (PDF) and Proportional Intregral Differential with First Order Filters in the Differential Section (PIDF). For the transition analysis, the observed parameters consist of rise time, peak time, steady state time, maximum pass value and peak value. The results of the analysis show that the controller that meets the design criteria is a Proportional Differential (PD) controller with an uptime parameter value of 0.2808 seconds, a peak time of 1.3354 seconds, a steady state time of 0.7017 seconds, a maximum pass of 0% and a peak value of 0.9512. For the Proportional Differential controller with First Order Filter in the Differential Section (PDF) with an increase time parameter value of 0.4177 seconds, a peak time of 1.4684 seconds, a steady state time of 0.8453 seconds, a maximum pass of 0% and a peak value of 0.9502.

This service activity will be focused on everything related to assembly, software installation and computer troubleshooting for participants in the Karang Putih Community Learning Center (PKBM). The activity steps are carried out in several stages, starting from field surveys, literature studies, discussions, to the implementation of training activities that use an approach between theory and practice. Indicators of the success of this activity are the Assembly Training, Software Installation and Computer Troubleshooting. This training is used by partners, by seeing that this training has been in accordance with the needs of the community in the partner environment; This training can help the educational process and skills in practice quickly; and this training can be conducted by other Community Learning Activity Centers (PKBM). The attention of the participants in this activity was quite large, almost all of them were active in the discussions and practices that were carried out. From this discussion and training it was revealed that about 75% of the participants had understood the material as a whole.

Pemanfaatan teknologi informasi dan telekomunikasi (ICT) sebagai media promosi dan komunikasi di Indonesia masih kurang berkembang. Kondisi ini memberi peluang kepada masyarakat untuk lebih memanfaatkan teknologi ini terutama di sektor pendidikan baik formal maupun nonformal. Hal ini memberikan dampak yang signifikan terhadap kemajuan aktifitas pendidikan di berbagai negara. Pengunaan teknologi teknologi informasi dan telekomunikasi (ICT) terutama teknologi internet merupakan cara yang inovatif dalam melaksanakan berbagai program pendidikan. Dengan memanfaatkan teknologi internet, lembaga pendidikan formal dan nonformal dapat melakukan berbagai kegiatan secara elektronik seperti media forum, email, mailing list dan berbagai aktifitas lainnya. Pondok Pesantren Modern Terpadu Dr. Muhammad Natsir Alahan Panjang. merupakan salah satu lembaga pendidikan yang mengintegrasikan nilai – nilai keagamaan dan ilmu pengetahuan dalam proses belajar mengajarnya. Agar masyarakat luas mengetahui tentang aktivitas pondok pesantren modern pada umumnya dan Pondok Pesantren Modern Terpadu Dr. Muhammad Natsir Alahan Panjang khususnya maka dikembagkanlah suatu webiste. Website ini nantinya dapat digunakan sebagai media promosi dan komunikasi bagi Pondok Pesantren Modern Terpadu Dr. Muhammad Natsir Alahan Panjang.

Training of Computer network using Miktrotik at the Integrated Modern Islamic Boarding School of Dr. Muhammad Natsir at Alahan Panjang is one of the solutions to overcome the problem of the effectiveness and efficiency computer user. The training was started by a field survey to laboratory of the information and communication technology (ICT) at the School. In this survey, discussions were held on what problems are very important and get priority to find solutions in increasing the effectiveness and efficiency of computer use at the School. The results of the survey agreed that computer network training with Mikrotik would be held in order to increase the effectiveness and efficiency of computer use on it. The second activity was the preparation of computer network training with Mikrotik. Preparation was carried out in the form of discussions with teammates to determine materials and methods that were more efficient and effective in the implementation of computer network training with Mikrotik at the Information and Communication Technology (ICT) laboratory. The results of the discussion agreed that the training would be provided in the form of presentations and hands-on practice. The third activity was the implementation of computer network training with mikrotik. This training was provided for 2 days, namely Saturday and Sunday. The first day was done by shared knowledge about the basics of computer networks and Mikrotik. The second day, students did a computer network training with Mikrotik. The fourth activity was the evaluation of computer network training activities with Mikrotik, to evaluate the activities that have been carried out and to obtain suggestions and input for future improvements.

Penjual nasi goreng merupakan salah satu profesi yang mempunyai waktu tidur yang kurang dikarenakan aktifitasnya di malam hari. Dengan aktifitas berjualannya rata- rata dari jam 17.00 s/d 03.00 membuat penjual tidak beristirahat pada malam hari dan merasa lelah sehingga waktu tidurnya berkurang. Di kota Bengkulu pada umumnya penjual nasi goreng bekerja hingga larut malam, sehingga rentan terhadap peningkatan gula darah, yang dapat berlanjut menjadi diabetes mellitus tipe 2. Normalnya kadar glukosa darah sewaktu yaitu kurang dari 200 mg/dL. Kadar glukosa darah yang tinggi dalam tubuh menandakan penyakit Diabetes Mellitus. Tujuan dari penelitian ini diketahui Gambaran Kadar Glukosa Darah Sewaktu pada Penjual Nasi Goreng di Kecamatan Singaran Pati Kota Bengkulu Tahun 2019. Jenis Penelitian ini yang digunakan deskriptif, yaitu penelitian yang dilakukan untuk menggambarkan suatu phenomena yang terjadi di kalangan masyarakat. Populasi dalam penelitian ini adalah penjual nasi goreng di kecamatan singaran pati kota Bengkulu. Teknik pengumpulan data yang digunakan pada calon responden dalam penelitian dan peneliti melakukan wawancara yang meliputi identitas responden. Didapatkan hasil kadar glukosa normal sebanyak 34 responden (97,2%) dan 1 responden (2,8%) kadar glukosanya abnormal. Maka dapat disimpulkan bahwa hasil kadar glukosa hampir seluruh responden yaitu normal dengan jumlah 34 orang (97,2%) dan sebagian kecil responden abnormal dengan jumlah 1 orang (2,8%).

Latar Belakang: Tinea pedis salah satu penyakit infeksi yang disebabkan oleh jamur yang sering terjadi dan ditemukan di daerah kulit telapak kaki dan sela jari kaki. Salah satu spesies jamur penyebab penyakit ini adalah Trichophyton rubrum. Beberapa faktor resiko dari penyakit ini adalah orang yang sering bekerja ditempat basah atau orang yang setiap hari harus memakai sepatu tertutup dalam waktu yang lama, bertambahnya kelembapan karena keringat, dan paparan jamur. Tujuan: Untuk mengetahui prevalensi Tinea pedis yang disebabkan oleh jamur Trichophyton rubrum pada sela jari kaki wanita pembelah ikan di Pemukiman Nelayan Kota Bengkulu. Metode: Jenis penelitian ini menggunakan desain survei deskriptif cross sectional. Data yang dikumpulkan merupakan data primer. Sampel penelitian ini sebanyak 24 responden kerokan kulit sela jari kaki wanita pembelah ikan. Hasil pemeriksaan jamur Trichophyton rubrum di laboratorium diperiksa secara makroskopis dan dilanjutkan dengan pemeriksaan mikroskopis. Hasil: Hasil penelitian menunjukkan bahwa prevalensi kejadian Tines pedis pada wanita pembelah ikan di Pemukiman Nelayan Kota Bengkulu sebesar 37,5% atau sebanyak 9 orang dari 24 responden yang diperiksa diperoleh hasil positif. Kesimpulan: Prevalensi infeksi jamur Trichophyton rubrum pada wanita pembelah ikan di Kampung Sejahtera sebesar 37,5%. Distribusi frekuensi berdasarkan karakteristik faktor resiko (Menggunakan sepatu boots, Penggantian kaos kaki, kebisaan mencuci kaki, dan Lama bekerja dalam sehari).

Background: Diabetes mellitus is a chronic metabolic disease or disorder with multietiology (many causes) which is characterized by high blood sugar levels accompanied by impaired carbohydrate, fat, and protein metabolism as a result of inadequate insulin function. Cherry leaves as an alternative medicine for diabetes mellitus, are used by boiling the carcinoma leaves using water. Boiling process attracts polar compounds found in cherry leaves, cherry leaves contain saponins and flavonids which can inhibit the absorption of blood sugar from the intestine, thus inhibiting the absorption of carbohydrates. Method : this research uses descriptive type with Cross Sectional research design. Sample selection with snowball sampling method. There were 32 respondents, namely type II diabetes mellitus who consumed cherry leaf boiled water (20 routines, and 12 non-routine). M ethod of blood sugar levels using a glucometer. Results : blood sugar levels in patients with type II diabetes mellitus who consume boiled water cherry leaves regularly at 20 probandus (40% normal and 60% abnormal) obtained an average of 166.6 mg / dl and standard deviation of 35,905, not routine (100% abnormal) an average of 211.3 mg / dl was obtained and a standard deviation of 76,935. Conclusion : cherry leaves boiled water when consumed regularly and regularly can reduce blood sugar levels of patients with type II diabetes mellitus. Keywords: Blood glucose, DM type II, Cherry leaves.

Oksigen dibutuhkan manusia agar proses metabolisme sel berjalan baik, dimana paru-paru berperan dalam proses pengambilan oksigen dari atmosfer menuju tubuh. Penurunan fungsi paru memberikan buruk diantaranya: terganggunya fungsi metabolisme, penurunan stamina dan daya tahan tubuh, risiko serangan jantung dan stroke meningkat, fatigue, penurunan fokus umum, konsentrasi dan memori, serta meningkatkan respon peradangan (Davis, 2013). Alat utama dalam test fungsi paru adalah spirometer untuk mengukur perubahan volume paru dengan pertukaran gas yang ada diatmosfer (Ronal, B et al, 2015). Jenis penelitian ini deskriptif analitik dengan rancangan cross sectional. Penelitian dilakukan pada 109 orang mahasiswa Jurusan Keperawatan Poltekkes Kemenkes Bengkulu. Data didapat dari pengisian kuesioner, pengukuran berat badan, tinggi badan dan kapasitas paru. Analisis data dilaksanakan secara kuantitatif yaitu univariat dan bivariat. Berdasarkan hasil penelitian didapatkan bahwa sebagian besar (87.2%) responden memiliki kapasitas paru kurang, sebagian kecil (11.9%) responden obesitas, lebih dari separuh (65.1) responden tidak punya kebiasaan berolahraga. Tidak ada hubungan antara obesitas dan kapasitas paru (p=0.140). Ada hubungan bermakna antara kebiasaan olahraga dan kapasitas paru (p=0.005). Berdasarkan hasil penelitian ini masa akan datang disarankan untuk melihat pengaruh beberapa faktor lain terhadap penurunan kapasitas paru.

This paper presents an analysis of optimal micro hydropower (MH) capacity of hybrid systems to improve renewable energy based power systems. The electricity system was designed by considering river water flow data and solar radiation data at the research location of Universitas Andalas (Unand). Optimal results obtained for the configuration of the Grid, MH, and photovoltaic (PV) with a head height of 30 m and a flow rate of 800 L/s with the lowest Cost of Energy (CoE) value of $ 0.065. As an optimal sizing system has been able to increase the composition of renewable energy generation in the Unand electrical network. The renewable energy fraction has increased from 26.4% to 36.5%. Therefore, determining the optimal capacity will increase the use of renewable energy generation. Conversely, an increase in electricity supply from renewable energy plants will reduce electricity consumption from the State Electricity Company (Perusahaan Listrik Negara, PLN) grid. The latest excess power generation at a low load can be sold to the PLN grid.

Puskesmas yang menjadi salah satu tempat pelayanan kesehatan pertama. Untuk menjamin pelanyanan kesehatan yang baik di Puskesmas maka ketersediaan logistik kesehatan salah satunya obat harus dapat dijamin. Tujuan penelitian ini adalah untuk mengevaluasi dan menganalisa permasalahan terkait kondisi ketersediaan logistik obat di Puskesmas pada wilayah Kota Bengkulu. Penelitian ini menggunakan metode pendekatan kualitatif dengan wawancara mendalam dan survei sebagai cara untuk mengumpulkan data. Data yang digunakan adalah voice recorder dan dokumen laporan ketersediaan obat di puskesmas. Informan penelitian ini sebanyak 14 orang yang terdiri dari Dinas Kesehatan Kota Bengkulu, Plh Kepala UPTD Farmasi Dinkes Kota Bengkulu, Apoteker/Staf penanggung jawab farmasi di Puskesmas. Hasil penelitian menunjukkan bahwa ketersediaan obat di Puskesmas wilayah Kota Bengkulu belum sesuai dengan kebutuhan puskesmas. Rata-rata persentase ketersediaan obat di Puskesmas mencapai 97% dan telah melampaui target yang ditetapkan oleh pemerintah yaitu 95%, akan tetapi yang terjadi di lapangan adalah pemenuhan pelayanan kesehatan yang berkaitan dengan obat tidak mencukupi. Pengadaan obat belum sesuai dengan LPLPO yang dibutuhkan oleh puskesmas. Disarankan Kementerian Kesehatan terkhususnya Ditjen Kefarmasian dan Alat Kesehatan melakukan evaluasi kembali dalam penggunaan Formulir Ketersediaan Obat di Puskesmas sebagai instrumen dalam penetapan sasaran kinerja.

This study discusses the application of Polar Placement method using Bass - Gura algorithm on Non - Reheat type frequency electric control system with emphasis on frequency deviation on power system. The performance indicators of electric power system that can be calculated and observed include error analysis, response speed, response quality, frequency domain analysis, stability analysis and robustness analysis of the frequency deviation response of electric power system. The simulation results show that the non-reheat type deviation of electric power with Polar Placement method shows better result compared to non-reheat type frequency power deviation response without the Polar Placement method with a steady state error value of 0.0041, the rise time value of 0.0562 second, the peak time value is 0.0049 seconds, the time value of the steady state is 0.5113 seconds, the maximum pass value is 19.2112%, the root of the characteristic equation which all the parts are negative, the maximum peak value is 1.0049 and the maximum peak value of complementary sensitivity is 0.0051. Keywords: Frequency Deviation, Polar Placement, Bass - Gura Algorithm, Non – Reheat

This journal discussed the stability analysis of generator excitation control system in type of direct current without and by using controller. The stability Analysis was conducted on absolute stability analysis, relative stability analysis and internal stability analysis. For the absolute stability analysis was demonstrated by using gain margin and phase margin value. In order to get satisfied system performance so that cultivated gain margin value was greater than 6 dB and phase margin value was in ranges from 30 0 to 60 0 . For the relative stability was shown by the peak value of resonance. The system would be relatively stable if the peak value of resonance range was between 1:10 to 1:50. The system would be internal stable if all closed circle transfer functions from input to internal output was stable. For internal stability indicator was shown by number 0 if the system is internally stable and number 1 if the system was internally unstable. For controllers used consisted of Proportional controller (P), Proportional Integral controller (PI), Proportional Differential controller (PD) and Proportional Integral Differential controller (PID). The controllers were designed with a frequency response approach. The results showed that the voltage response of generator excitation system type direct current with Proportional controller (P), Proportional Integral controller (PI), Proportional Differential controller (PD) and Proportional Integral Differential controller (PID) was stable of absolute, relative and internal. With Proportional controller (P), the voltage response of generator excitation system type direct current had 4.2542 (12.5760 dB) in gain margin value, 50.5290 degrees in phase margin value, 1.2136 (1.6816) in resonance peak value and 0 in internal stability index. With Proportional Integral controller (PI), the voltage response of generator excitation system type direct current had 4.3362 (12.7420 dB) in gain margin value, 49.0000 degrees in phase margin value, 1.2391 (1.8624 dB) in resonance peak value and 0 in internal stability index. With Proportional Differential controller (PD), the voltage response of generator excitation system type direct current had 16.6910 (24.4490 dB)in gain margin value, 54.0000 degrees in phase margin value, 1.1030 (0.8516 dB) in resonance peak value and 0 in internal stability index. For Proportional Integral Differential controller (PID), the voltage response of generator excitation system type direct current had 8.9451 (19.0320 dB) in gain margin value, 50.0000 degrees in phase margin value, 1.1792 (1.4316 dB) in resonance peak value and 0 in internal stability index. Keyword: Excitation system, absolute stability, relative stability, internal stability, frequency response Abstrak — Jurnal ini membahas tentang analisa kestabilan sistem kendali eksitasi generator tipe arus searah tanpa dan dengan pengendali. Analisa kestabilan yang dilakukan meliputi analisa kestabilan mutlak, analisa kestabilan relatif dan analisa kestabilan internal. Untuk analisa kestabilan mutlak ditunjukkan dengan menggunakan nilai margin penguatan dan nilai margin fasa. agar performansi sistem memuaskan maka diusahakan nilai margin penguatan ini besar dari 6 dB dan nilai margin fasa berkisar antara 30 0 sampai 60 0 . Untuk kestabilan relatif ditunjukkan dengan nilai puncak resonansi. Sistem akan bersifat stabil relatif jika nilai puncak resonansi berkisar antara 1.10 s/d 1.50. sistem akan bersifat stabil internal jika semua fungsi alih lingkar tertutup dari masukan ke keluaran internal bersifat stabil. Untuk indikator kestabilan internal ini ditunjukkan oleh angka 0 jika sistem bersifat stabil internal dan angka 1 jika sistem bersifat tidak stabil internal. Untuk pengendali yang digunakan terdiri dari pengendali Proporsional (P), pengendali Proporsional Integral (PI), pengendali Proporsional Diferensial (PD) dan pengendali Proporsional Integral Diferensial (PID). Pengendali – pengendali tersebut dirancang dengan pendekatan tanggapan frekuensi. Hasil yang diperoleh bahwa tanggapan tegangan sistem eksitasi generator tipe arus searah dengan pengendali Proporsional (P), pengendali Proporsional Integral (PI), pengendali Proporsional Diferensial (PD) dan pengendali Proporsional Integral Diferensial (PID) bersifat stabil mutlak, stabil relatif dan stabil internal. Dengan kontroler Proporsional (P), respon tegangan generator eksitasi jenis sistem arus searah memiliki 4,2542 (12,5760 dB) nilai marjin keuntungan, 50,5290 derajat nilai fasa, 1,2136 (1,6816) dalam resonansi nilai puncak dan 0 dalam indeks stabilitas internal. Dengan kontroler Proportional Integral (PI), respon tegangan dari jenis sistem eksitasi generator arus searah memiliki 4,3362 (12,7420 dB) nilai marjin keuntungan, 49,0000 derajat nilai fasa, 1,2391 (1,8624 dB) di resonansi nilai puncak dan 0 dalam stabilitas internal yang indeks. Dengan kontroler Proporsional Differential (PD), respon tegangan dari jenis sistem eksitasi generator arus searah memiliki 16,6910 (24,4490 dB) nilai marjin keuntungan, 54,0000 derajat nilai fasa, 1,1030 (0,8516 dB) di resonansi nilai puncak dan 0 dalam stabilitas internal yang indeks. Untuk Proporsional Integral Diferensial controller (PID), respon tegangan dari jenis sistem eksitasi generator arus searah memiliki 8,9451 (19,0320 dB) nilai margin keuntungan, 50,0000 derajat nilai fasa, 1,1792 (1,4316 dB) di resonansi nilai puncak dan 0 di intern indeks stabilitas. Kata kunci : sistem eksitasi, kestabilan mutlak, kestabilan relatif, kestabilan internal, tanggapan frekuensi

The Rogowski Coil sensor is one of the sensors used to detect aging insulation, which is marked by the occurrence of Partial Discharge. Aging is damaged, which fails power tools when operated. If the insulation is aging and even causing damage, the distribution of electrical energy will be disrupted. This research presents two types of Rogowski Coil sensor core materials to detect Partial Discharge with the same number of turns. The number of turns is 5. The first sensor is a sensor with a ferromagnetic core and the second sensor is a sensor with a non ferromagnetic core. The test of the sensor is carried out by using a magnitude test using a charge calibrator as an imitation of Partial Discharge. The magnitude of the Partial Discharge read by the sensor uses a digital oscilloscope with an impedance of 50 Ohm. Measurement results compared to commercial sensors. The measurement results read by the oscilloscope found that the type of sensor core influences the magnitude value of Partial Discharge. The magnitude of the Partial Discharge sensor with a ferromagnetic core is greater than that of a sensor with a non ferromagnetic core. However, both results are much smaller than the commercial sensor even though the digital oscilloscope can read them.

The SARS-CoV-2, a virus that attacks the respiratory system, has some difficulty breathing and chest pain. A mechanical ventilator is a simple version of a ventilator and most used to support patient breathing because it iseasy to use. This research design a mechanical ventilator operate based on the frequency and air volume of inspiration. The operator can set the ventilator using a potentiometer and choose the menu on an LCD. A couple of press wall push a bag valve mask in the desired frequency. The motor speed has a vital role to perform the number pushing based on the desired setting. The amount of airflow out from this bag depends on the duration and the depth of pushing. Some standard frequencies of human breathing were investigated in the range of 12 to 20 times of inspiration in a minute. The acceleration of the ventilator based on calculation was implemented to the machine, and it reduced the number frequency to 64% of the desired frequency. An error compensator is used to improve the accuracy of the ventilator. It compensates by multiply calculated acceleration by 2.31. It is successfulin improving the performance and resulted in the ventilator work in the desired frequency and volume.

This paper reports the steady-state performance of a grid-connected photovoltaic-wind power system in a 20 kV active distribution system. The system was initially designed to meet a typical of State Electricity Company (Perusahaan Listrik Negara, PLN) primary feeder in Indonesia. In this study, 200 kWp solar power capacity and 200 kW wind power capacity were selected in the simulation of power flow analysis to evaluate the better system states. The results of the study using four cases show that the better voltage profile is obtained in conditions where the hybrid system is placed on the bus, which has the lowest voltage and on the load bus, which farthest from the source. The presence of power injection from solar and wind power plants on low voltage (LV) buses has reduced the active power flow from the grid utility. All load bus voltages have above 0.95 p.u in these cases, already within PLN standard. The lowest level of losses of 11 kW and 50 kVAr are obtained in the case where hybrid Photovoltaic (PV) and Wind Turbine (WT) with capacitor integration in the distribution network. Power losses are secured far below 10% as the losses permitted according to the PLN standard. Therefore, the integration of PV and wind turbine into a 20 kV distribution network can improve the voltage profile and reduce total system losses.

Partial-discharge is a symptom of high voltage insulation aging, which is a small voltage pulse with high frequency and superposition with high voltage sources that have low frequencies. To find out the existence of this signal, it needs a reliable measurement technique to avoid misinterpretation. This paper presents a technique for measuring partial discharge with an induction method. The sensor used is circular twin loops. The first loop passes through a partial discharge signal, and the second induction receiver produces an induced voltage signal. Various sizes of loop diameters are designed with dimensions 3.2, 4.7, 8.9, and 11.4 cm to look for sensor sensitivity. The performance sensor is analyzed by reading the sensitivity test to the input given with 50-ohm oscilloscope impedance. From the measurement results, the higher the diameter of the sensor loop has good sensitivity.

In the process of power system development planning necessary to have a forecast of electricity demand in the future. The results obtained estimates can be considered for policymakers to formulate measures to be taken for the future. It aims to achieve optimization in the process of supplying electrical energy. To optimize the energy supply of electricity in the province of West Sumatra required an estimation of electrical energy. In this study, estimation methods used are fuzzy logic. Estimates carried out long term, ie until 2018. Estimated long-term electric energy demand is generally based on past statistics and analysis based on energy consumption characteristics ago. Such characteristics are usually influenced by several factors, such as population, number of electricity customers, electrification ratio, and so forth. The fuzzy logic method uses historical data / actual accumulated in several time periods, namely from 2000 to 2008. Results estimated by using fuzzy logic shows that the electrical energy needs in West Sumatra province in 2018 amounted to 3610 GWh. This value is not much different from the estimates made by PLN, which amounted to 3998.5 GWh. Error between the estimated value of fuzzy logic in 2018 and PLN was 5:48%.

Electric power systems produce power that can be used for various purposes. The distribution of electrical power and its relationship to the voltage and current generated by the generator. Voltage can change with changes in load. The change of voltage is undesirable due to it can cause disturbances to the power system. A device called Automatic Voltage Regulator (AVR) is used to maintain the voltage stable. This AVR is equipped with a control system to get the voltage stability following the specified criteria. In this study, the Ziegler -Nichols (Z-N) method is used with the First Order Plus Dead Time (FOPDT) approach. FOPDT is used for AVR control based on frequency response and transfer function methods. AVR used is direct current type AVR. The design that fulfils the criteria for controlling the voltage transfer response of direct current type AVR systems is the Proportional Integral Differential (PID) controller. This PID is designed using the Ziegler-Nichols method with the FOPDT approach based on the transfer function method. Information on the simulation results of the direct current type of system switching AVR response is obtained where the steady-state error value is 0.0000, the rise time value is 0.6114 seconds, the peak time value is 1.4391 seconds, the peak value is 1.1492 seconds, the maximum throughput is 14.942% and time to state steady reaches value at 2.5562 seconds. The values of parameter control are k of 13.2000, L of 0.4283, T of 1.0817, Proportional constant (Kp) of 0.2296, integral time constant (Ti) of 0.8564 and differential time constant (Td) of 4.6667. Keywords : Ziegler-Nichols, Fisrt order plus dead time, Automatic voltage regulator, Transient analysis Abstrak Sistem tenaga listrik menghasilkan daya yang dapat di gunakan untuk berbagai keperluan. Penyaluran daya listrik ini erta hubungan nya dengan tegangan dan arus yang di hasilkan oleh pembangkit. Tegangan dapat berubah-ubah dengan berubahnya beban. Perubahan tegangan ini tidak diinginkan karena dapat mengakibatkan gangguan pada sistem tenaga. Untuk menjaga agar tegangan tetap stabil digunakan Automatic Voltage Regulator (AVR). AVR ini dilengkapi dengan sistim pengendalian untuk mendapatkan kestabilan tegangan sesuai dengan kriteria yang di tetapkan. Pada penelitian ini digunakan metoda Ziegler -Nichols (Z-N) dengan pendekatan First Order Plus Dead Time (FOPDT) berdasarkan tanggapan frekuensi dan metoda fungsi alih sebagai metoda pengendali AVR dan AVR yang digunakan adalah AVR tipe arus searah.Pengendali yang memenuhi kriteria rancangan untuk pengendalian tanggapan peralihan tegangan sistem AVR tipe arus searah adalah pengendali Proporsional Integral Diferensial (PID). Pengendali Proporsional Integral Diferensial (PID) ini dirancang dengan menggunakan metoda Ziegler-Nichols dengan pendekatan First Order Plus Dead Time (FOPDT) berdasarkan metoda fungsi alih. Informasi hasil simulasi tanggapan peralihan sistem AVR tipe arus searah yang diperoleh dimana nilai kesalahan keadaan mantap sebesar 0.0000, nilai waktu naik sebesar 0.6114 detik, nilai waktu puncak sebesar 1.4391 detik, nilai puncak sebesar 1.1492 detik, nilai lewatan maksimum sebesar 14.942 % dan nilai waktu keadaan mantap sebesar 2.5562 detik. Untuk nilai parameter pengendali yang digunakan adalah k sebesar 13.2000, L sebesar 0.4283, T sebesar 1.0817, konstanta Proporsional (K p ) sebesar 0.2296, konstanta waktu integral (T i ) sebesar 0.8564 dan konstanta waktu diferensial (T d ) sebesar 4.6667. Kata Kunci :Ziegler-Nichols, Fisrt order plus dead time, Automatic voltage regulator, Analis peralihan

This journal discusses about performance analysis of generator excitation system voltage response towards parameters changes. Changes in the parameters of the generator excitation system will affect the response voltage generator excitation system performance, in both time domain and frequency domain performances. The performance analysis of the generator excitation system voltage response in both time domain and frequency domain, conduct with the help of Matlab software. For performance in the time domain is consists of error analysis and transient analysis, while for performance in the frequency domain is consists of the open-loop performance and closed-loop performance. The parameters that to be changed are the amplifier gain constant, amplifier time constant, generator gain constant, and generator time constant. The analysis result shows that the performance of the generator excitation system voltage response in both time domain and frequency domain performances is very sensitive towards the changes in the parameters, especially for the changes of amplifier gain constant, the changes of amplifier time constant, the changes of generator gain constant, and the changes of generator time constant. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";}

The journal discusses the evaluation and calculation of the termination time of the critical electrical system stability studies Sumatra through the transient stability by using the Runge-Kutta method Order 4. For this type of disorder transition used is a three-phase symmetrical disorder with the help of MATLAB software. The calculation result shows that the value of the smallest critical time termination occurs between PLTGU Belawan - GI Ombilin Binjai and power plant - GI Batusangkat at 0:24 seconds. While the most critical time of termination occurs at a power plant Pauh Limo - GI Indarung at 1:14 seconds. Keywords : Stabilitas peralihan, runge – kutta orde 4, waktu kritis pemutusan . Abstrak Jurnal ini membahas tentang evaluasi dan perhitungan waktu pemutusan kritis dari sistem kelistrikan Sumatera melalui studi kestabilan peralihan dengan menggunakan metoda Runge-Kutta Orde 4. Untuk jenis gangguan peralihan yang digunakan adalah gangguan tiga fasa simetris dengan bantuan perangkat lunak Matlab. Hasil perhitungan diperoleh bahwa nilai waktu pemutusan kritis terkecil terjadi antara PLTGU Belawan – GI Binjai dan PLTU Ombilin – GI Batusangkat sebesar 0.24 detik. Sedangkan waktu pemutusan kritis terbesar terjadi pada PLTG Pauh Limo – GI Indarung sebesar 1.14 detik. Kata Kunci : Stabilitas peralihan, runge – kutta orde 4, waktu kritis pemutusan

This paper presents partial discharge (PD) measurement techniques using a commercial sensor, High-Frequency Current Transformer (HFCT). An Output signal from HFCT is read by a digital oscilloscope and compared with the reading of convensional that PD detector. When PD occurs, the signals detected using high impedance that has a long time of oscillations and cause the delay of next reading of PD signals. To avoid this issue, the time of oscillations must be reduced by installing a damper which is a resistor connected in parallel between the sensor and the oscilloscope. The result of the measurement shows that the damper has the same reading on peak values as read by the convensional PD detector.

This paper presents the development of Rogowski coil to detect the partial discharge. Rogowski coil sensor is composed of a ferrite core with a various number of turns which is 5, 10, 20 and 30 turns with a half circle and full circle configuration. The sensors need to be tested based on the number of the turns they have in reading the partial discharge signals. The sensor is connected to a digital measurement device such as a digital oscilloscope which has an input impedance of 50 ohms and 1 Mohm with a time frame duration greater than or equal to 20 ms. The reading comparison is not only between the proposed sensors but also with a commercial partial discharge sensor. The partial discharge signal is generated by a commercial charge calibrator. The measurement result shows that using low impedance lead to decreased noise but the reading is too small compared with using high impedance.

This paper discusses the evaluation of the voltage profile of electric power systems based on power flow analysis by the Newton Raphson method. The aim of power flow analysis is to obtain information about the voltage profile of the system under operating conditions in a steady state in order to evaluate the performance of the electric power system and analyze the conditions of generation and loading of both normal and emergency conditions. The results of the analysis show that there are several load buses which voltage values are below 1.0 pu. In anticipation of a greater voltage drop, reactive power injection is carried out in the form of mounting a certain value capacitor on these buses and obtaining a greater and greater voltage magnitude equal to 1.0 pu

The good operation of metal oxide surge arresters depends on the increment of temperature. If the arresters cannot quickly disperse the absorbed energy into the ambient, arresters temperature may exceed its operating temperature limit. Consequently, thermal runaway occurs and results in power loss. In this paper, thermal characteristics and thermal stability based on power loss calculation were investigated. Applied voltages, leakage current, and temperature were the main parameters consideration. The power loss calculated by the electrical model is the input to the thermal model. The electro-thermal model is used to determine the two intersection points (stable operating point and the thermal instability point) of the power input and heat loss curves. The results show that irrespective of the different magnitude voltages applied to the arrester and different energy ratings for the elements, the power loss occurs at the certain applied voltage.

System stability is an inportant part in the planning and operation of electric power systems, especially dynamic stability. The ability of a power system to maintain stability under small disturbances defined as dynamic stability. The small disturbances consist of load variation in generation side in random, slow and cascaded. This condition may change system frequency which effect in system stability and can not work normally. The aim of this research is to design suitable control system via simulation to respond small disturbances in the power system. The simulation test system is used PT. PLN data Sumbar-Riau system under Linear Quadratic Regulator (LQR) method. The method is used to obtain control value to reach desagn criteria, that are overshoot less then 5 % and steady state time less then 4 second. The simulatino result shows that the system design have reach the criteria of design at 0.65 times basic load to 1.35 times of basic load. Ke ywords : Dy nami c stability, controller, Linear Quadratic Regulator (LQR) Abstrak Pada perencanaan dan operasi sistem tenaga listrik, kestabilan sistem adalah hal yang sangat penting terutama kestabilan dinamik. Kestabilan dinamik adalah kestabilan sistem terhadap gangguan kecil. Gangguan kecil ini berupa perubahan beban pada sisi pembangkit secara acak, pelan, dan bertingkat. Gangguan ini mengakibatkan perubahan frekuensi yang menyebabkan kestabilan sistem berubah sehingga tidak mampu bekerja secara normal. Tujuan penelitian ini untuk mendapatkan informasi perancangan pengendali melalui simulasi untuk memperbaiki kestabilan sistem akibat perubahan beban kecil. Simulasi dilakukan pada sistem tenaga listrik PT. PLN Sumbar-Riau dengan menerapkan metoda Linear Quadratic Regulator (LQR). Metode ini digunakan mendapatkan nilai pengendali agar dapat memenuhi kriteria rancangan yang diinginkan, yaitu lewatan maksimum tidak lebih dari 5 % dan waktu keadaan mantap kurang dari 4 detik. Hasil simulasi menunjukkan rancangan pengendali memenuhi kriteria pada kondisi 0.65 kali beban dasar sampai dengan 1.35 kali beban dasar. Ke ywords : Dy nami c stability, controller, Linear Quadratic Regulator (LQR)

In power systems, the behavior patterns of excitation system voltage is very important to note because it can affect the voltage stability of the power system. Several previous studies showed performance behavior pattern generator excitation system voltage is less than satisfactory at the point of operation. Under these conditions, conducted a study of the patterns of behavior of dynamic voltage generator excitation system with pole placement method using the Bass-Gura algorithm. With the help of information obtained by Matlab software, that behavior pattern generator excitation system voltage indicates better performance compared to the performance of the behavior patterns of excitation system voltage without the pole placement method. Keywords: generator excitation systems, pole placement method, bass-Gura, performance Abstrak Dalam sistem tenaga listrik, pola tingkah laku tegangan sistem eksitasi merupakan hal yang sangat penting untuk diperhatikan karena dapat mempengaruhi kestabilan tegangan sistem tenaga listrik. Beberapa penelitian terdahulu menunjukkan performansi pola tingkah laku tegangan sistem eksitasi generator yang kurang memuaskan pada titik operasinya. Berdasarkan kondisi tersebut, dilakukan suatu studi dinamik mengenai pola tingkah laku tegangan pada sistem eksitasi generator dengan metoda penempatan kutub menggunakan algoritma Bass-Gura. Dengan bantuan perangkat lunak Matlab diperoleh informasi, bahwa pola tingkah laku tegangan sistem eksitasi generator menunjukkan performansi yang lebih baik dibandingkan performansi pola tingkah laku tegangan sistem eksitasi tanpa metoda penempatan kutub. Keywords: generator excitation systems, pole placement method, bass-Gura, performance

Dalam sistem tenaga listrik, perilaku tegangan sistem eksitasi merupakan hal yang sangat penting untuk diperhatikan karena dapat mempengaruhi kestabilan tegangan sistem tenaga listrik. Beberapa penelitian terdahulu menunjukkan performansi perilaku tegangan sistem eksitasi generator yang kurang memuaskan pada titik operasinya. Berdasarkan kondisi tersebut, dilakukan suatu studi dinamik mengenai perilaku tegangan pada sistem eksitasi generator dengan metoda penempatan kutub menggunakan algoritma Bass-Gura , algoritma Ackerman, algoritma Robust Pole Placement dan stabilizer sebagai pembanding nantinya. Dengan menggunakan perangkat lunak Matlab diperoleh bahwa dengan menggunakan metoda penempatan kutub, perilaku tegangan sistem eksitasi generator menunjukkan performansi yang lebih baik dibandingkan performansi perilaku tegangan sistem eksitasi tanpa metoda penempatan kutub dan dengan stabilizer . Kata Kunci : sistem eksitasi generator, metoda penempatan kutub , bass-gura, ackerman, robust pole placement, stabilizer

Dalam pengendalian kecepatan motor arus searah, model sistem bersifat nonlinier. Untuk menganalisa pola tingkah laku disekitar titik operasi, salah satu model sistem adalah dengan dilinierisasi di titik operasi. Berdasarkan model sistem yang dilinierisasi tersebut diperoleh fungsi alih motor arus searah dan dirancang pengendali Proporsional (P), Proporsional Integral (PI), Proporsional Diferensial (PD) dan Proporsional Integral Diferensial (PID) melalui suatu simulasi dengan menggunakan perangkat lunak Matlab serta pendekatan tempat kedudukan akar. Hasil simulasi didapatkan nilai konstanta Proporsional (P), konstanta Integral (I) dan konstanta Diferensial (D) pengendali yang mengendalikan kecepatan motor arus searah. Kata Kunci : motor arus searah (DC), pengendali proporsional (P), pengendali proporsional integral (PI), pengendali proporsional diferensial, pengendali proporsional integral diferensial (PID), tempat kedudukan akar.

Closed-loop configuration has been introduced to Spatial Audio Coding (SAC) which make it possible to minimise distortion introduced during the quantisation and encoding processes. Significant performance improvement has been shown and reported in some papers. However, implementation of closed-loop system directly to MPEG Surround (MPS) is still problematic due to the unbalanced-delay filterbank that is used in the MPEG standard which is not appropriate for a closed-loop system that needs synchronisation between the original audio signals with the target audio signals. In this paper, we investigate the delay characteristic of the Quadrature Mirror Filterbank (QMF) which is used in several MPEG standards. Based on this study, a balanced-delay QMF is proposed and tested in a closed-loop MPS system. The results of the experiments show that approximately 8 dB of SNR improvement is achieved when applying balanced-delay filterbank compared to the unbalanced-delay filterbank as specified in MPS.