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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.