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Electrical power is a very important source for life. One of the electrical components is a distribution transformer which is used to transmit electrical voltage from the substation to the load center. Every year the electricity demand increases, so that the transformer works optimally, you must also pay attention to the loading. Load imbalance on electric power distribution transformers always occurs and this imbalance occurs due to the use of electrical energy. The current flowing in the neutral conductor of the transformer causes an imbalance in the transformer load and losses, namely losses due to the neutral current in the neutral conductor of the transformer. When analyzing mass, use quantitative methods. After analysis, it shows that the transformer is in an unbalanced state where neutral current appears in the transformer. To determine the efficiency of the distribution transformer  

Lightning has always been a dangerous threat to the equipment of electric power systems consisting of: power plants, substations, transmission lines and distribution lines. Generally, overhead high-voltage transmission lines are exposed to lightning strikes. Therefore, the degree of protection against lightning is determined based on the degree of insulation of the equipment. To prevent damage to equipment due to lightning strikes, arresters are used. In this study, three arrester models were used as comparisons, namely. IEEE arrester model. The system was simulated using Alternative Transients Program (ATP) software. The results showed that the lightning rod was declared successful in protecting the transmission system, where the three lightning rods had a Margin Protection (MP) of arresters that reached 28%. In the simulation, it is known that the IEEE arrester successfully cut off the lightning current in the transmission system so that the transient overvoltage recorded on the transformer does not exceed the Basic Insulation Level ((BIL) trafo.  

A reliable, efficient and high quality electrical energy supply is certainly very necessary. Frequent damage to electronic equipment and practical equipment in Building A, Faculty of Science and Technology (FST), Jambi University, prompted the author to conduct research on analyzing the quality of electrical power in this building. The research aims to analyze the quality of electrical power in building A FST. The research method used is the observation method which cannot influence the variables studied but can only record and observe the data that has been measured. The power quality quantities measured are voltage, current, active power, reactive power, power factor, voltage harmonics and current harmonics in each main panel. Based on the research results, the problem that occurs in the main panel of transformer A is load imbalance, namely at a percentage of 5.56% to 6%, the standard set by the IEC is only 5%. and the occurrence of current harmonic distortion (THDi) at a percentage of between 24%, the standard set by IEEE is 12%. The problem that occurs in the main panel of transformer B is that it has a low power factor value in the R and T phases, namely below 0.85. The occurrence of load imbalance is at a percentage of 10.9% to 12%, the standard set by the IEC is only 5%. The occurrence of voltage fluctuations is +7.4%, the standard according to PUIL 2011 is +5% with a value of 231 Volts and -10% with a value of 198 Volts and the occurrence of current harmonic distortion (THDi) is very high at a percentage of 29.83% to 58.419%, the value permitted by the IEEE standard is 15%.

Along with the development of the times, the need for electricity is very necessary. Electrical energy is one of the energy that is needed in using equipment that is related to electrical energy such as household, office and commercial industrial equipment that requires electrical energy. Bawean Island is one of the islands that requires a large amount of electricity due to the growing development of these sectors. With the rapid development of large-scale developments, the need for electricity needs to be increased in order to meet people's demands related to electricity needs. Technical losses are losses that occur for technical reasons where energy is reduced by turning into heat or heat energy. Basically technical losses occur based on energy losses in components caused by errors in the components themselves. Technical losses that occur in distribution transformers are common. In principle, losses always occur because efficiency cannot be 100%. Energy is lost along with distribution from upstream to downstream of distribution transformers. Based on the formulation of the problem taken, the researchers calculated losses at neutral currents, copper losses, total losses, output power and total losses in the form of prices. From the results of the conclusions above, it can be seen that the greater the current in the neutral of the transformer, the more losses that occur in the transformer.

The MotoGP One race in West Nusa Tenggara Lombok, Mandalika which was held on March 18 2022, received many responses or reactions from the public on social media, especially Twitter. There are those who agree and disagree about the holding of MotoGP in Mandalika, to find out the responses of the people who agree or disagree is needed that can process tweets data using the sentiment analysis method. The use of BERT (Bidirectional Encoder Representations from Transformers) for sentiment analysis produces a bidirectional language model that can understand the context of all words from a sentence. The dataset used goes through preprocessing stages such as case folding, data cleaning, tokenization, normalization, and removal of stopwords before sentiment analysis is carried out. This study uses several hyperparameters, namely a batch size of 32, the optimizer uses Adam with a learning rate of 3e-6 or 0.000003, and an epoch of 25. The evaluation results of the model obtain an accuracy of 55%. Precision for positive by 56%, neutral by 59%, and negative by 44%. Recall for positive is 74%, neutral is 29%, and negative is 54%. F1-score for positive is 64%, neutral is 38%, and negative is 48%.

Electrical systems use high-voltage insulation as a cooling agent. A breakdown voltage will show up to indicate insulation failure if the applied voltage is greater than the liquid insulation's dielectric strength. According to SPLN '50-1982 and IEC No. 56 of 1991, the typical breakdown voltage of PERTAMINA MESRAN transformer oil insulation at 30°C temperature before cleaning or treatment is 14.59 kV / 2.5 mm. Insulation of transformer oil is categorized as a sub-interest. (in a 30 Kv/2.5 mm manner). According to SPLN '50- 1982 and IEC No. 56 of 1991, the average breakdown voltage of PERTAMINA MESRAN transformer oil insulation at 300C temperature after cleaning/remediation process is 15.18kV / 2.5mm. Insulation of transformer oil is designated as standard ((standard). usually 2.5 mm/30 Kv). According to SPLN '50- 1982 and IEC No. 56 of 1991, the average breakdown voltage of SHE LL increase the oil-insulated transformer at 30°C temperature before cleaning / treatment Process is 16.52kV / 2.5mm. Transformer oil insulation (30Kv/2.5mm nominal) is viewed as being insufficient. According to SPLN'50-1982 and IEC No. 56 of 1991, the average breakdown voltage of SHELL formed transformer oil insulation at 30°C temperature after cleaning and treatment is 22.83 kV / 2.5 mm. A division below the standard (30 Kv / 2.5 mm is common) is transformer oil insulation.

In transformers installed and used in electric power systems, especially at substations (GI) there are often disturbances or problems. One of the problems with the transformer can occur due to the failure of the insulating oil which can be caused by a decrease in the value of the translucent voltage, therefore it is necessary to carry out maintenance to prevent and localize interference. Tap Changer oil is different from oil in the main tank (in terms of placement), in terms of type and function Tap Changer oil with oil in the main tank has similarities from the type of oil and its function as insulation, cooling and protecting windings from oxidation. With the method of observation (observation) in the field of all equipment worked on and with the literature method can be known the process of replacing oil On Load Tap Changer. From the results of the oil translucent voltage test study, it is known that the value of the penetrating voltage of the On Load Tap Changer oil sample used in the transformer is an average value of 38.8 kV, it can be known that the value of the new oil penetrating voltage (sample 1) being filtered is 86.8 kV, the value of the new oil penetrating voltage (sample 2) being filtered is worth 88 kV, and the value of the new oil penetrating voltage (sample 3) being filtered is 98.2 kV.

Research has been carried out on the load imbalance analysis on the transformer with the aim of knowing the percentage of load imbalance on the transformer. From the results of the analysis that has been carried out, it is known that the percentage of transformer loading is unbalanced and is in bad condition because it exceeds the balance standard that has been set, which is above 25% with a percentage for line 1 of 60% during the day and 80% at night. While on line 2 has a percentage of 35% during the day and 33% during the day.

Load imbalance in three-phase distribution transformers can increase neutral current and power losses, thereby reducing the efficiency and reliability of electric power distribution systems. This study aims to analyze the level of load imbalance, power losses caused by neutral current, and the effectiveness of manual load balancing using the two-time-point method, namely peak load time (PLT) and off-peak load time (OPLT). The research was conducted on the PNIAI007 distribution transformer at PT PLN (Persero) ULP Enarotali using a quantitative descriptive approach with a case study design. Data were obtained through measurements of phase currents and neutral current, which were then analyzed to compare conditions before and after load balancing.The results show that the load imbalance level was significantly reduced from more than 29% to 2.47% during daytime operation and 1.21% during nighttime operation. The neutral current decreased from 37.81 A to 14.58 A during the daytime and from 51.76 A to 19.83 A at night. In addition, power losses due to neutral current were reduced by more than 85%. These results indicate that the two-time-point load balancing method is effective in improving the efficiency and operational reliability of distribution transformers.