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All Journal Program Kreativitas Mahasiswa - Teknologi JAREE (Journal on Advanced Research in Electrical Engineering) Jurnal Nasional Teknik Elektro dan Teknologi Informasi
Mochammad Wahyudi
Universitas Gadjah Mada
Computer Science & IT Control & Systems Engineering Electrical & Electronics Engineering Energy Engineering

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SPIN DRY-PAD: MESIN PUTAR PENGERING PADI BERBASIS SISTEM OTOMASI UNTUK MENINGKATKAN KUALITAS DAN PRODUKTIVITAS PADI UD SUMBER REJEKI Adhim, Mochammad Machrus; Wahyudi, Mochammad; Yunansha, Dony; Maulida, Nadhifa; Ayu, Nur Ika Puji
Program Kreativitas Mahasiswa - Teknologi PKM-T 2013
Publisher : Ditlitabmas, Ditjen DIKTI, Kemdikbud RI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (137.739 KB)

Abstract

The climate change causing rice production decreases, particularly on rice drying process before being milled rice. At the observation at UD Sumber Rejeki that the drying process of rice in the rainy season suffered a loss of 900,000/ton. To minimize the production process failed in drying rice process, made a rice dryer technology with automatic dialing systems, as well as controlling the temperature and moist content in the precision can be set as needed (Spin Dry-Pad). The Result when using Spin Dry Pad, UD Sumber Rejeki can increase domestic rice production during rainy season with operational cost only 191.500/ton and the quality of rice produced according to the standart PUSLITBANG agriculture department of Indonesia, which the moisture of rice is 14%.
Demagnetization Method for Reducing Inrush Current of Single Phase 1 kVA Transformer I Made Yulistya Negara; Dicky Wahyu Darmawan; Ryan Nurdianto; Dedet Candra Riawan; Arif Musthofa; Dimas Anton Asfani; Mochammad Wahyudi; Daniar Fahmi
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 1, No 1 (2017): April
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25796216.v1.i1.4

Abstract

This study deals with an effort to reduce inrush current of single phase transformer during its energizing. Inrush current affected by residual flux was minimized using demagnetization method in order to reduce residual flux trapped in the core of transformer. Two methods of demagnetization namely variable frequency-constant voltage (VFCV) and variable voltage–constant frequency (VVCF) were applied and the effectiveness of both methods were then compared. Both methods were supplied with alternated direct current (DC), however the one was changed its frequency and the other one was changed its voltage. The results obtained after transformer was demagnetized using these methods show that VFCV method educed inrush current up to 76%, on the other hand VVCF ethod reduced inrush current only up to 37%. Moreover, demagnetization time process of VFCV method was about 1.46 s, which is 1 s faster than VVCF method.Keywords: demagnetization; inrush current; variable voltage-constant frequency; variable frequency-constant voltage
Design of Motor Current Signature Analysis (MCSA) Based on LabVIEW for Online Detection of Induction Motor Faults Dimas Anton Asfani; Soedibyo Soedibyo; I Made Yulistya Negara; Daniar Fahmi; Muhammad Eko Septiawan; Mochammad Wahyudi; Neisya Islamey Rifma
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 1, No 2 (2017): October
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25796216.v1.i2.20

Abstract

Induction motor is the most common used electric motor in industry. Along with its operation, induction motor can savere certain damage which is generally dominated by internal fault, such as s rotor fault, stator fault, and bearing fault. In this paper, the online detection based on motor current signature analyses (MCSA) for such faults was designed using LabVIEW. MCSA was performed to obtain the frequency which indicated the presence of certain damage of induction motor. The experimental result showed that the accuracy of proposed method reached 90 %. Keywords: induction motor; online detection; rotor fault; stator fault; bearing fault; MCSA.
Ferroresonance Signal Analysis with Wavelet Transform on 500 kV Transmission Lines Capacitive Voltage Transformers I Gusti Ngurah Satriyadi Hernanda; I Made Yulistya Negara; Adi Soeprijanto; Dimas Anton Asfani; Mochammad Wahyudi; Surya Dwi Kisdarmawan; Daniar Fahmi
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 1, No 1 (2017): April
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25796216.v1.i1.8

Abstract

This paper deals with ferroresonance detection on an transmission line utilizing wavelet transform. The ferroresonance involving linear capacitor and non-linear inductor was triggered by the disturbances of power system, such as lightning strike, switching operation and ground fault. The primary voltage of capacitive voltage divider (CVT) was observed as response of the triggered ferroresonance. The voltage signal was processed using wavelet daubechies (db5) until 9 levels. The cyclic cumulative energy for each condition was then calculated and compared. The result shows that the cyclic cumulative energy ratio and duration of period of cumulative energy deviation can be used as ferroresonance detection parameters.Keywords: ferroresonance; capacitive voltage divider, wavelet transform
Analysis of Breakdown Voltage Test on Transformer Oil based on Dissolved Gas Analysis Test Result I Made Yulistya Negara; Dimas Anton Asfani; Daniar Fahmi; Roikhana Farista Dewira; Mochammad Wahyudi; Made Yudha Pranadiksa Giri
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 2, No 2 (2018): October
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25796216.v2.i2.55

Abstract

Transformer which has full-load and used continuously will create heat on the core, so that oil insulation is required. The impact of gases in oil insulation to breakdown voltage has been not investigated yet. This research implied an information about the impact of gases in insulation oil to breakdown voltage. Multiple linear regression with 300 data was the method used in this research. Analysis had been conducted on each gas, all gases, three combinations of gasses, four combination gases without acetylene, and three combination gases without acetylene. The target of this research was to know the impact of gases in oil transformer to the value of breakdown voltage. The results showed that the gasses had impact of 0.325 on breakdown voltage classified as a slight impact for breakdown voltage. Keywords: DGA, BDV, Transformer Oil, Double Linear Regression
Impact of Shape and Total of Particle to Characteristics of Partial Discharge and Breakdown Voltage on Oil Insulation in Uniform Field Daniar Fahmi; I Made Yulistya Negara; R. Wahyudi; Dimas Anton Asfani; Made Yudhi Setyawan; Mochammad Wahyudi
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 2, No 1 (2018): April
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25796216.v2.i1.35

Abstract

Oil insulation is one of the insulation medium types commonly used in high voltage apparatus. This insulation is to separate between the conductive part and non-conductive part. However, oil insulation can experience decreasing of dielectric strength. It may be caused by the presence of solid particles. Therefore, the testing was conducted to obtain the effect of solid particles to characteristics of partial discharge and breakdown voltage of oil insulation. The results generally proved that the existence of solid particles can reduce the breakdown voltage value of oil insulation. In addition, the solid particles led to two types of corona on oil insulation, namely positive and negative corona. Keywords: oil insulation; partial discharge; breakdown voltage; corona; particle shape; particle total.
Detection of Partial Discharge in Oil Filled-Tank using Acoustic in Audio Frequency Mochammad Wahyudi; Noor Akhmad Setiawan; Bambang Sugiyantoro; I Made Yulistya Negara; Gilang Adityasakti
JAREE (Journal on Advanced Research in Electrical Engineering) Vol 5, No 1 (2021): April
Publisher : Department of Electrical Engineering ITS and FORTEI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/jaree.v5i1.105

Abstract

In this paper, the acoustic signal within an audio sonic range emitted by partial discharge (PD) in an oil-filled cylindrical tank was investigated. The PD was generated by point-to-flat electrodes subjected to a high-voltage DC. The PD source location, installation method, and sensor microphone, as well as the electrode gap distance, were varied. Subsequently, acoustic waveforms and their frequency spectrum, as well as the PD current, were analyzed. The results showed that transient acoustic signals indicated the emergence of PD. The acoustic sensor attached to the outer wall of the tank (contact type) was more sensitive than the sensor that had a distance from the tank (non-contact type). Sensor contact type acoustic signals placed parallel to the location of the PD source provided a more accurate signal form compared to those set nonparallel to the frequency spectrum, which was relatively flat. A closer electrode distance caused the duration, acoustic signal amplitude as well as the currents to be more considerable. For the identical variable, the acoustic signal form was not related to the current signal despite the same signal duration. Besides, locations of sources of the PD notably influenced the signal form, but it did not apply for the current signal.Keywords: acoustic, audio frequency, fast Fourier transform, high-frequency current transformer, oil transformer, partial discharge
Evaluasi Degradasi Isolasi Motor akibat Multi-factor Aging berdasarkan Indeks Polarisasi dan SEM-EDX Mochammad Wahyudi; Dimas Anton Asfani; I Made Yulistya Negara; Daniar Fahmi; I Gusti Ngurah Satriyadi Hernanda
Jurnal Nasional Teknik Elektro dan Teknologi Informasi Vol 8 No 1: Februari 2019
Publisher : Departemen Teknik Elektro dan Teknologi Informasi, Fakultas Teknik, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1189.562 KB)

Abstract

The operation of induction motor affected by stress factor causes insulation degradation. This degradation can be observed from changes in insulation characteristics, including electrical, physical, and chemical. This study aimed to evaluate the insulation resistance (IR) and polarization index (PI) since the induction motor condition was good until burned out. Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy ( SEM-EDX) testing was also carried out to analyze changes in microstructure, morphological characteristics, and chemical composition in stator windings. In addition, X-ray powder diffraction ( XRD) testing was presented to validate that the damaged insulation was caused by the given stress. To accelerate degradation of insulation, induction motor in service condition was subjected by a lot of pressure simultaneously, including thermal, moisture, and salt contamination. The accelerated aging testing was gradually conducted according to three schemes with different pressure levels. The results showed that the applied stresses could accelerate the insulation aging. A significant decrease of IR and PI values was found in the third scheme, as the IR value was less than 5 MΩ and the PI value was 0.6 (danger category). The insulation failure was achieved at a total duration of testing for 222 hours. The results of SEM-EDX and XRD testing showed the presence of mineral deposits from water vapor, salt contaminants, cracks, and fracture on the insulation surface.
Analisis Karakteristik Arus dan Tegangan pada Inisiasi Feroresonansi Transformator Tegangan Rendah I Gusti Ngurah Satriyadi Hernanda; I Made Yulistya Negara; Adi Soeprijanto; Dimas Anton Asfani; Mochammad Wahyudi; Daniar Fahmi
Jurnal Nasional Teknik Elektro dan Teknologi Informasi Vol 7 No 2: Mei 2018
Publisher : Departemen Teknik Elektro dan Teknologi Informasi, Fakultas Teknik, Universitas Gadjah Mada

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Abstract

Ferroresonance is an interaction phenomenon between non-linear inductance and capacitance that initiates abnormal waveform of current and voltage. This phenomenon is very sensitive to system parameter and initial condition. In this paper, ferroresonance initiation involved a basic circuit of series ferroresonance with variation of source voltage magnitude on a single phase low voltage transformer. The scheme of experiment was based on the case of transformer energizing. The trends of current and voltage waveform on the primary windings were investigated and transformed by using Fast Fourier Transform (FFT). The harmonics spectrum was then employed to identify the feroresonance mode and calculate the Total Harmonics Distortion (THD) of current and voltage. The experimental results showed that the higher source voltage magnitude caused the ferroresonance responses to be seen more clearly. It was indicated by the more distorted waveform, the higher odd harmonics frequency amplitude especially for 150 Hz, and the greater THD. Based on the harmonics spectrum and wave period, the ferroresonance responses were identified as fundamental mode. The effects of initial conditions, such as residual flux of transformer and capacitor charge, were also seen on the distorted wave peak during transient condition. In addition, the difference of waveform between normal and ferroresonance condition could be more easily observed on the voltage than the current. The waveforms of current and voltage during experiment had been verified by using simulation.
Co-Authors Adi Soeprijanto Bambang Sugiyantoro Daniar Fahmi, Daniar Dedet Candra Riawan Dicky Wahyu Darmawan Dimas Anton Asfani Dony Yunansha Gilang Adityasakti I Gusti Ngurah Satriyadi Hernanda I Made Yulistya Negara Made Yudha Pranadiksa Giri Made Yudhi Setyawan Mochammad Machrus Adhim Muhammad Eko Septiawan Musthofa, Arif Nadhifa Maulida Neisya Islamey Rifma Noor Akhmad Setiawan Nur Ika Puji Ayu R. Wahyudi Roikhana Farista Dewira Ryan Nurdianto Soedibyo Soedibyo Surya Dwi Kisdarmawan