Jurnal Nasional Teknik Elektro
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359 research outputs found
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Signal Lights-Based Light Vehicle Safe Movement on Underground Mine Ramps
Full text linkThe safe movement of Light Vehicles (LVs) is jeopardised on underground mine ramps due to the single lane nature of ramp and the use of ramp by Heavy Vehicles (HVs). Two-way traffic flow dynamics in single-lane underground mine haulage ramps do affect productivity of ramp in times of ore transportation from underground to the surface for processing. In this research, we made use of traffic signal lights, Radio Frequency (RF) Transmitters (Tx) and Receivers (Rx) and a traffic signal lights module to safeguard LV motion on underground ramp. Simulation outcomes confirm safe movement of LV in the midst of HV and other LV on the haulage ramp. This development assures of safety of LV and stands to minimise the incidents occurrences rate in mine ramp haulage systems
Analysis of Electronic Load Controller with Bidirectional Converter in Self-Excited Induction Generator
Full text linkInduction generators are widely used in small-scale power plants driven by renewable energy, such as wind, mini/micro-hydro, tidal wave, biomass, biogas, etc. In applying this generator to a micro-hydropower plant, it is usually equipped with an ELC (Electronic Load Controller), which regulates the frequency to remain constant at a safe tolerance limit (49.8 – 50.2 Hz). However, this system is still not optimal because the ELC dumps its excess power into the dummy load. This paper proposes an ELC system that can adjust the frequency to remain constant without wasting excess power from the generator. This system uses the working principle of a bidirectional converter, which can regulate the flow of power from the generator and dummy load in two directions. In the proposed system, the dummy load uses a battery to store excess electrical energy and be utilized and reused when needed. Performance analysis of the proposed system uses simulation with MATLAB Simulink software. The induction generator used has a voltage specification of 380 Y, 50 Hz, 1420 rpm, 3.5 A, and 1.5 kW. The analysis results show that the developed ELC design can adjust the frequency in the value range of 49.98-50.01 Hz during load changes with a range of 955 Watt to 1.045 Watt, with the response time reaching its steady-state value of 0.1-0.4 seconds
Intermittent Oscillation Diagnosis in a Control Loop Using Extreme Gradient Boosting
Full text linkThe control loop in the industry is a component that must be maintained because it will determine the plant's performance. Most industrial controllers experience oscillations with various causes, such as noise, oscillation, backlash, dead band, hysteresis, random variation, and poor controller tuning. The oscillation diagnosis system, which can understand the oscillation type characteristics, is built based on machine learning because it is dynamic and not based on specific rules. This study developed an online oscillation diagnosis program using the extreme gradient boosting (XGBoost) method. The data was obtained through the simulation of the Tennessee Eastman process. The data is segmented on specific window sizes, and then time series feature extraction is performed. The extraction results are then used to build an XGBoost model capable of performing oscillation diagnosis tasks. There are seven types of oscillations tested in this study. The model that has been made is implemented online with the help of sliding windows. The results show that the XGBoost model performs best when the data window size is 100, with the accuracy performance and the F1 score of the model in classifying the type of oscillation being 0.918 and 0.905, respectively. The model can detect the type of oscillation with an average diagnosis time of 712 seconds on diagnostic tests
Feasibility Analysis of Distributed Power Control System for Cognitive Radio Networks
Full text linkThe need for an efficient transmit power is affected by the condition of user and power control methods used. User conditions that categorized in cognitive femtocell networks included in the category as distributed user, so it required a distributed power control (DPC). To be implemented in cognitive radio network (CRN) communication, the system must be feasible. The problem raised in this research regarding the feasibility of implementing the DPC system on the CR network To meet the feasible requirements, it is necessary to test the system's feasibility through testing the eigenvalues of the link gain matrix obtained and testing the non-negative power vector conditions. In this study, experiments were carried out on 2 schemes of the number of users, namely the scheme of 5 users and 10 users, to determine the power requirements of each user according to the channel distribution. The results obtained for both schemes show that the total eigenvalue of the link gain matrix for all channels is less than 1 and all users meet the non-negative power vector requirements. So it can be concluded that those two schemes are feasible to implement a distributed power control system. Furthermore, as more users use the channel and the closer the distance between users, the more power is consumed due to high interference, necessitating high power compensation in order to maintain the target of signal to interference and noise ratio (SINR)
Gas Production by Monoester of Saturated Fatty Acids under Electrical Fault
Full text linkThis paper deals with the gas production by monoester oil intended to be used as insulating oil under an electrical discharge of low energy. The monoester contains only saturated fatty acids in its hydrocarbon chain. The electrical fault was realized by implementing an AC high voltage to hemispherical shaped electrode pairs with the gap of 2.5 mm immersed in the oil sample. The voltage application was paused when the breakdown occurred in oil and re-applied repeatedly up to 50 and 75 times to allow a high concentration of gasses produced by the oil sample. The resulting gasses were extracted from the oil sample using the headspace method and then analyzed using gas chromatography (GC). Fault identification methods, like DGA status, Key Gas, Duval Triangle, and IEC Ratio, were performed to predict the fault causing the production of such gasses. The results are compared with those of the monoester of unsaturated type. It is found that the Key Gas method is applicable for both oils under electrical discharge. The Duval Triangle and the IEC Ratio methods diagnose the electrical discharge in both monoesters but overestimate them as high energy discharge
Model Design of The Image Recognition of Lung CT Scan for COVID-19 Detection Using Artificial Neural Network
Full text linkCOVID-19 has become a pandemic and is a big problem that needs to be checked out immediately. CT scan images can explain the lung conditions of COVID-19 patients and have the potential to be a clinical diagnostic tool. In this research, we classify COVID-19 by recognizing images on a computer tomography scan (CT scan) of the lungs using digital image processing and GLCM feature extraction techniques to obtain grayscale level values in CT images, followed by the creation of an artificial neural network model. So that the model can classify CT scan images, the results in this research obtained the most optimal model for COVID-19 classification performance with 90% accuracy, 88% precision, 91% recall, and 90% F1 score. This research can be a useful tool for clinical practitioners and radiologists to assist them in the diagnosis, quantification, and follow-up of COVID-19 cases
Distribution Transformer Synchronization Simulation with Two Different Vector Groups using the Matlab Simulink
No full textNowadays, the quality of electrical energy really needs to be improved especially for industrial purposes that require a good level of reliability in the distribution of electrical energy. Maintenance of distribution transformers is routinely carried out to ensure that the quality of electrical energy produced is in accordance with standards. This maintenance is done using the customer’s load from the distribution transformer to the mobile substation transformer, that can be done using synchronization. This synchronization requires the same distribution transformer vector groups, otherwise it will produce non-standard output. The aim of this research is to determine the vector groups effect on parallel transformer installation system, the method to overcome the synchronous problem of different vector groups based on simulating and testing the synchronization of a 20 / 0.4 kV distribution transformer with the Dyn5 and Dyn11 vector groups. The results obtained from this research are two transformers that have different vector groups can be synchronized with an abnormal connection (changing the position of the secondary terminal cable connection and the primary terminal cable) so that it will produce the same voltage phase. This will abnormal treatment of distribution transformers maintenance that do not have a back-up transformer with the same vector group still can use the different vector group transformers
The Design of Soil Temperature and Humidity Monitoring Systems with IoT-Based LoRa Technology
Full text linkSoil temperature and humidity are important factors in affecting the condition of agricultural sector, which has an impact on the quality and quantity of the production. Lack of information on the condition of agricultural soil is one of the causes in productivity deficiency in the process of agricultural cultivation. The application of technology in the field of agriculture is expected to be able to reduce various adverse effects of agricultural soil conditions. One of which is by periodic monitoring, such as the temperature and humidity of agricultural soil. This research aims to design LoRa technology to be used as a data transmission medium for monitoring soil temperature and humidity by applying a system that is based on the Blynk application, which will make the users easier to monitor the system remotely. The temperature sensor was able to acquire data with 98.37% accuracy and the soil humidity sensor was able to acquire data with 91.63% accuracy. The changes in LoRa transmission parameters for monitoring data have an effect on the quality of its performance. The experimental results with Bandwidth variation (BW) from 31.25 kHz, 62.50 kHz, 125 kHz, 250 kHz, and 500 kHz at a distance of 15m, the best SNR and RSSI values were obtained for BW 31.25 kHz with values of 5.42 dB and -104.90 dBm. Whereas, the best ToA is obtained with a BW of 500 kHz with a value of 27.50 ms. While, the experimental result with the variation of Coding Rate (CR) from CR 4/5, 4/6, 4/7, and 4/8 at a distance of 15m, the best SNR and RSSI values were obtained CR 4/8 with values of 4.10 dB and -106.40 dBm and he best ToA was obtained CR 4/5 with a value of 112.70 ms. In testing by using variation Spreading Factor (SF) from SF7, SF9, and SF12, the higher the SF value used, the wider the range of area data communication will be. Configuration SF7 and SF9 were only able to reach a distance of 25m, while SF12 was able to reach a distance of 35m
Techno-Economic Simulation of On-grid PV System at a New Grand Mosque in Bukittinggi using HOMER
Full text linkMosque is an important building for Muslims worldwide for doing religious activities, such as daily prayers, weekly discourses, and annual celebrations. In many places, mosques are considered appropriate buildings for rooftop solar photovoltaics (PV) installation. This study provides a techno-economic analysis of an on-grid PV system in a great mosque. As a case study, Masjid Tablighiyah Garegeh in Bukittinggi is chosen, which is currently under construction with an expected capacity of up to 1,400 people. This study uses HOMER software as a tool to assess optimum configuration for an on-grid PV system. There are four options that is considered in this study: PV-grid, PV-battery-grid, battery-grid, and grid only system . Optimization results showed that both configurations with PV have promising performance; however, an on-grid PV system without battery system is the most optimum configuration. A 40 kWp PV equipped with a 27 kW converter has the least net present cost with USD 6,902, while the cost of energy when implementing the system is only about USD 4.8 cent per kWh. By implementing the system, 57.2 MWh of electricity will be produced from the PV
Classification Of Alcohol Type Using Gas Sensor And K-Nearest Neighbor
Full text linkEthanol, isopropyl and methanol belong to the same alcohol group. The latter is commonly used as an industrial solvent, not for personal consumption. Many traditional alcoholic drink sellers often mix alcoholic beverages, which are commonly called as “oplosan”, this mixed drink is very dangerous for human if it contains methanol. Based on this problem, it is necessary to make a measuring device for the alcohol content in the liquid to classify the alcohol type. The design of this gas sensor-based alcohol classification system and method consists of a series of hardware and software applications. The block diagram of the alcohol classification system measures the ethanol and methanol substances in each alcoholic drink using the MQ3 gas sensor and WeMos as a data acquisition device and microcontroller. The computer was used to process the acquisition data from the gas sensor being used then calculates the K-Nearest Neighbor (K-NN) to obtain the prediction results. The K-NN system testing consists of testing the effect of the K value and testing its accuracy. The result of testing the effect of the K value produces 100% optimum accuracy at the values namely K=1, K=3, K=5, K=10 and 55% on K=20