Electrical Energy Supply Research Articles

Analisa Dan Rancang Bangun Alat Pendeteksi Gangguan Fuse Cut Out Melalui Notifikasi Telegram Berbasis Global Positioning System

The electric power system must be able to provide a continuous supply of electrical energy with a standard amount of voltage and frequency in accordance with applicable regulations and the system must immediately return to normal conditions if the system experiences a disturbance. This tool is used to detect faults and the location of the fuse cut out (FCO). PZEM-004T sensor to read the voltage of each phase. Neo-6M GPS to get the coordinates of the location which is accessed via Google Map, then the Telegram bot sends a message to the feeder status information, the location connected to the Google Map, the transformer address and the voltage value after the disturbance. The average difference between the actual location distance to the location recorded by GPS NEO-6M is 4.10 meters and recorded by GPS Coordinates is 6.90 meters. The average percentage error of voltage values for each phase in the measuring instrument and in the sensor is in the R = 0.62 % phase, S = 8.94 % and T = 8.57 %. The Telegram bot sends a message when the FCO in the S phase is decided, namely the S Phase status is Lost, because the voltage in the S phase decreases from 221.9 V AC to 117.7 V AC, with the average duration of sending Telegram bot messages is 41.3 seconds.

Multi-Phase Power System Simulation

Abstract: Six Phase Transmission System has the capacity to increase the transmission capacity by 1.732 times the existing Three Phase System. It is possible to convert existing Three Phase Double circuit transmission line into compact Six Phase transmission line within the existing Right-of-way. Forecasting the demand and supply of Electrical energy gives the alternative solution is Six Phase Transmission system in addition to its several advantages like reduced phase voltage, less corona, declined magnetic field etc. This paper presents the study and analysis of design of transformer for six phase system. Comparison by system count per unit use MATLAB and PSCAD/ EMTDC simulation implemented for both system. Analysis of data carried out for parameters as value phase difference, voltage, current and power in transmission line. Apart from that assessment choosing the best transformer design for six phase system also implemented. From the analysis data performed found line system six phase have successfully produced ascendant as many as 73% in the division transmission line over system double three phase circuit. Apart from obtain that the best connection six phase system to acquire stated ascendant is delta Star delta inverted Star connection and diametrical connection

The Effect Of Distributed Generation (DG) Placement On Electricity Reliability

The continuity of the supply of electric power is becoming a greater demand from consumers. Feeder MRA05 GI Mrica Banjarnegara supplies electrical energy for parts of Banjarnegara Regency until 2020 has 4 distributed generations, namely PLTMH Sigebang 500 KW, PLTMH Kincang 320 KW, PLTMH Adipasir 320 KW, PLTMH Rakit 500 KW. Based on recorded data in 2020, the MRA05 feeder experienced 15 blackouts/year, with a total outage duration of 38.68 hours/year, of course it was enough to disrupt the continuity of the distribution of electrical energy to consumers. This research discusses the magnitude of the reliability index (SAIFI, SAIDI, CAIDI) when the DG is not installed and installed. The calculation of the magnitude of the reliability index was carried out using the Reliability Index Assessment (RIA) method, the calculation results were compared with the results of the ETAP 12.6.0 software simulation. The reliability index is based on the RIA method when DG is not installed, the SAIFI value is 2.96228 interruptions/year, the SAIDI value is 9.1185 hours/year, the CAIDI value is 3.078 hours/interruption, When DG is installed, the SAIFI value is 2.96228 disturbances/ year, the SAIDI value is 7.567 hours/year, the CAIDI value is 2.5546 hours/interruption.

A three-dimensional unsteady numerical model on a novel aerogel-based PV/T-PCM system with dynamic heat-transfer mechanism and solar energy harvesting analysis

The daily increasing energy demand combined with global environmental issues has promoted the development of a photovoltaic thermal (PV/T) system with onsite electrical and thermal energy supply in buildings. However, suffering from massive radiative and convective heat losses, the overall efficiency of PV/T systems is relatively low (normally lower than 70%). In this paper, silica aerogel, a spectral selective porous material with high solar transmittance, extra-low thermal conductivity and low mid-infrared emissivity, is integrated into the upper surface of PV/T systems to reduce heat losses. Meanwhile, composite phase change material (PCM) with active heat-transfer enhancement strategies is integrated at the backside for accumulated heat dissipation. Subsequently, a three-dimensional numerical model based on the finite volume method and enthalpy-porosity method is established in the commercial software Ansys Fluent to simulate the dynamic performance. Dynamic heat-transfer mechanism is studied with solar energy harvesting analysis subjected to the typical weather conditions in Guangzhou, China. A series of comparative and parametric studies are performed for optimal structural design and operation. Results indicate that, the incorporation of aerogel and composite PCM with high thermal conductivity are beneficial to improve electrical and thermal efficiencies, while the integration of nanofluid shows negligible effects. The optimal results show the improvement on overall energy and exergy efficiencies by 40.2% and 1.5% in summer and by 42.4% and 0.43% in winter, together with annual CO2 mitigation of 104.1 kg/m2 and return on investment (ROI) of 0.169. This study provides a novel structural design and optimal operation on a novel aerogel-based PV/T-PCM system, together with guidelines on techno-economic-environmental performance improvement, promoting the solar energy harvesting for decarbonization transformations in buildings.

Impact of Tourist Areas on the Electrical Grid: A Case Study of the Southern Dominican Republic

The growing integration of tourist areas and complexes increases the demand for electrical power systems. This increased demand may represent a vulnerability to voltage and frequency stability in electrical grids, where these parameters are essential for an optimal and continuous supply of electrical energy. The Dominican Republic has begun a tourist expansion process in areas that were previously not commercially exploited. Based on the factors mentioned above, this article’s objective was to analyze the impact caused by the increase in electricity demand due to the tourism sector, using the Enriquillo Region of the Dominican Republic as a case study. The impacts of this expansion on the voltage profiles and the system’s frequency were determined. The methodology consisted of obtaining information on the mathematical model of the system to evaluate the expansion plan for the study period and the projection of the demand of the grid. The complete system was modeled with this information, including expansion and possible renewable generators. Finally, the flow of charges was measured, and dynamic analysis was carried out. The quasi-dynamic and RMS/EMT simulations were carried out in the DIgSILENT software for this investigation. The results showed that the electrical system benefits stability and national standards. This is because the transmission lines reduced their loading by approximately 2.99% in 2032. As the years of study passed and the system load increased, the voltage in the bars of the 138 kV systems and generators did not exceed the range of ±5% established in the technical regulations of the Dominican electricity market.

A Novel Flexible Method for Optimal Operation Modeling of Multi-Carrier Energy Systems

This research suggests a new flexible method for the optimal operation of multi-carrier energy systems based on optimization techniques for different weather conditions and seasons. The results apply to different modes (a hot summer day, a cold winter day and a normal day). A new cost function from the operator’s point of view is suggested considering the constraints on consumable gas supply and electrical energy in the cold and hot seasons respectively. Furthermore, a novel algorithm is suggested that gives the economical values of energy carriers, final cost, and the percentage of the direct electrical energy supply and outside the hub. In this method, load data, related prices, constraints, and penalties are applied to the suggested model, and afterward hub optimization assists in finding the optimal operation and costs. MATLAB software is used to check the results and the simulation outputs confirming the effectiveness of the proposed method.

Synchronization and Optimal Operation of a 140 kVA Inverter in On-Grid Mode Using Mamdani Controllers in Cascade

This paper addresses the synchronization and operation of a 140 kVA inverter system connected to the main grid as part of a decentralized microgeneration system. The considerations for the supply of electrical energy stored in battery banks, mostly of photovoltaic origin, involve a study of the details of a rigid nonlinear system, which parallels the generation and distribution standards typical of hydroelectric and thermoelectric plants. Considering aspects related to power electronics operation, this paper presents both the modeling and the controlling aspects necessary to synchronize and ensure a stable operation of the microgeneration systems when connected to the main grid. Statistical processing was developed to guarantee synchronization between the systems without presenting electric shocks by simulating the magnetic link in asynchronous generators to meet this aim. The proposed model simulates the increase in power by a phase shift by maintaining a constant frequency based on a Chirp wave generator. The proposed process considers a generation power baseband operation. A Mamdani-type fuzzy proportional-integral controller is used to determine the power setpoint, which sets the Chirp generator phase shift setpoint, which includes a Mamdani fuzzy proportional-type controller. Both controllers are connected in a cascade. The applied correlational technique to achieve the synthesis of the sinusoid and the synchronization presented optimal performance when using 17 samples per signal period. The design of the transformer primarily, guaranteed a phase shift of −4.3018°, allowed for a THD below 2.75%.

ELECTRICAL ENERGY SAVINGS BY UTILIZING INTERNET-BASED AUTOMATIC MONITORING AND CONTROL OF THINGS

Utilization of modern technology is almost inseparable from the use of electrical energy. There is often the use of electrical energy that is actually not needed (wasteful), wasteful use of electrical energy results in increased costs, increased power supply, which has an impact on increasing equipment capacity, the problem of saving electrical energy has been widely discussed but saving electrical energy is easy and can be controlled automatically and can be monitored remotely still needs to be improved. Saving electrical energy can have an impact on cost savings, as well as prevent a crisis in the supply of electrical energy. According to data from the Ministry of Energy and Mineral Resources, the installed capacity of power plants for the 2018-2020 period increased by 2.34% per year. The distribution of electricity to customers in the 2018 – 2020 period has increased by 1% per year. Monitoring and controlling electrical energy can be done using controls using sensors and can be monitored and controlled remotely based on the internet of things. This study aims to design and manufacture a prototype tool that functions to monitor and control electrical loads in real time from a distance based on the internet of things and by utilizing sensors can also help turn on and turn off electrical loads as needed. The method used is through the stages of Analysis, Design, Development, Implementation, Evaluation (ADDIE). The results of the study show that the designed and manufactured tools can monitor electrical loads whether they are on or off and can turn on or turn off electric loads automatically with the help of sensors and actuators and can also be controlled remotely via smartphones, laptops, computers or tablets. Future studies are expected to be able to control electrical parameters including voltage, current, frequency, real power, reactive power, apparent power, and power factor. The expected impact of this research is that it can control electrical energy automatically easily and can control it remotely and save electricity usage.

Prediction of Electric Vehicles Charging Demand: A Transformer-Based Deep Learning Approach

Electric vehicles have been gaining attention as a cleaner means of transportation that is low-carbon and environmentally friendly and can reduce greenhouse gas emissions and air pollution. Despite EVs’ many advantages, widespread adoption will negatively affect the electric grid due to their random and volatile nature. Consequently, predicting the charging demand for electric vehicles is becoming a priority to maintain a steady supply of electric energy. Time series methodologies are applied to predict the charging demand: traditional and deep learning. RNN, LSTM, and transformers represent deep learning approaches, while ARIMA and SARIMA are traditional techniques. This research represents one of the first attempts to use the Transformer model for predicting EV charging demand. Predictions for 3-time steps are considered: 7 days, 30 days, and 90 days to address both short-term and long-term forecasting of EV charging load. RMSE and MAE were used to compare the model’s performance. According to the results, the Transformer outperforms the other mentioned models in terms of short-term and long-term predictions, demonstrating its ability to address time series problems, especially EV charging predictions. The proposed Transformers framework and the obtained results can be used to manage electricity grids efficiently and smoothly.

Electrical Energy for Rural, Small Scale and Value Creation Industrialization in Mbozi District-Songwe, Tanzania

The study aims at investigating the impacts of steady electrical energy supply on industrialization. To reveal the nature of the relationship between the two variables i.e. steady electrical energy supply and industrial development, the study which was carried out in Mbozi district in Songwe region-Tanzania employed a survey research design. Moreover the investigation applied the strata-multistage sampling technique to derive to 101 respondents. Using documentary review and questionnaire the facts was gathered regarding the study in which processors, constructors, farmers and traders was a sample frame. Using a latent variable analysis, rotated component matrix and average variance expected data analysis tools it was revealed that steady supply electrical energy contribute positively towards industrial development. It was conclusively found that steady electrical energy supply and industrialization detailing rural industrialization, small scale industrialization and value addition was statistically significant at p>=0.05. Thus it is with these positive results what this study suggests to policy makers that the environment for sustainable electrical energy should be created for rural industrialization, small scale industrialization and value creation policies to be realized.

Fluctuations in the wind energy supply do not impair acceptance of wind farms

With the growing contribution of wind power to the electric energy supply, fluctuation in available wind energy might increasingly become part of public debate. Fluctuation influences energy prices and might lead to acceptance problems. As a first step to gauge potential communication strategies, we investigated in an experimental study if acceptance is influenced by being made aware of fluctuation. Participants either answered questions on acceptance before or after judging fluctuation and predictability for 30 days of wind energy input. To test for potentially biased cognition, we additionally checked if judgments were affected by whether or not it was transparent that the graphs showed wind energy input. Mean acceptance did not differ between the groups. Directing attention to the fluctuation of power generated by wind does not have an impact on acceptance. Additionally, presence or absence of labels on the graphs and thus knowing that the graphs depicted wind energy supply, did not affect fluctuation and predictability ratings.

Analisa Keandalan Transformator Distribusi Menggunakan Weibull Distribution di Wilayah ULP Rungkut Kota Surabaya

The reliability of the electric power system is very important in the continuity of the supply of electrical energy to the load. One of the important parts in the electric power system is the transformer. Maintaining the reliability of the transformer is an effort to make electrical energy channeled properly. For this reason, efforts are needed to evaluate whether the transformer is in good condition or not by using the Weibull distribution. By looking at the average failure rate, the MTTF value is used as a benchmark for reliability. It is based on the number of disturbances that cause the transformer to fail to operate. The results of the reliability analysis with the Weibull distribution on distribution transformers in the Rungkut ULP area during the time span from 2019, 2020, 2021 obtained an average failure rate of 18.321894% per year, with an MTTF value of 0.054579 per year, so the value reliability obtained 0.981. So according to Croanbach alpha, this value belongs to a very reliable level.

Study on the electrothermal coupling characteristics of different types of thermoelectric units

The electric heating characteristics of thermoelectric units refer to the coupling relationship between the generating power P and the steam extraction volume G of the unit for external heating. The heat supply forms of directly regulated public thermoelectric units mainly include steam extraction condensing heat supply and back pressure circulating water heat supply. Through the research on the electrothermal coupling characteristics of different types of thermoelectric units, we can master the electric load output range of thermoelectric units in the heating season, provide data support for the power grid dispatching department, effectively promote the consumption of new energy, and ensure the smooth and orderly supply of electric energy.

Proposals to improve the demand response in Brazil

The gradual commercial opening of electricity markets to keep pace with technological evolution and promote the active participation of players to increase their efficiency is recognized as one of the best practices in most developed markets in the world. The same principle applies to the Brazilian electricity sector, which increasingly demands intelligent mechanisms that serve as instruments to optimally face the increasingly complex challenges. Demand response (DR), a mechanism not widely used in Brazil, can offer many advantages to the electric system, such as increasing its competitiveness and improving the reliability of the electric energy supply through the active participation of the energy consumer. This study presents different paths and proposals by which the load side can contribute to increased energy security and avoid the increase in the system operating costs in Brazil. This study tracks the progress of the DR programs adopted in several international markets, observing their remuneration for the services provided to the electricity system, as well as the motivation of the operator, utilities, or market administrator to offer programs that allow the participation of consumers, resulting in benefits for the participant, programs, and system.

TECHO-ECONOMIC OPTIMIZATION OF HYBRID RENEWABLE ENERGY RESOURCES FOR ELECTRICAL POWER GENERATION: CONSIDERING JIBIA GENERAL HOSPITAL A CASE STUDY

Due to depletion of fossil energy supplies, climate change, absence of electric energy supply to remote locations, and high connection costs due to long distance, the embracing of Renewable Energy Systems (RES) has been recently accepted worldwide. Despite the problems described above, many countries are taking a long time to deploy renewable energy because of the high capital costs and uncertainty. Therefore, this work considered an optimized techno economic design of a standalone PV, Wind and Battery RES for power generation considering coordinate (13.0931◦N, 7.2248◦E) of Jibia Katsina state Nigeria, using Hybrid Optimization Model for Electric Renewables (HOMER) simulation software system. The simulation was carried out in three scenarios namely; PV and Battery, Wind and Battery, and PV, Wind and Battery. The Levelized Cost of Energy (LCOE) obtained from HOMER were found to be ₦44.14/kWhr, ₦29.63/kWhr and ₦29.48/kWhr respectively. The Loss of Power Supply Probability (LPSP) obtained from HOMER were found to be 0.0328%, 0.0021%, and 0.0137% respectively. The Excess Energy (ExE) produced from HOMER simulation were found to be 4,238kW, 7,710kW, and 3,523kW

Implementation Strategy for DC Fast Charging Stations for Electric Vehicles

Adoption of electric vehicles (EV) has been on a rising trend in the recent past. Provision of public DC fast charging infrastructure at strategic points is one of the major drivers towards the adoption of electric vehicles. This paper develops an implementation strategy for DC fast charging stations as an element in transmission and distribution infrastructure at strategic points to supply electrical energy for the recharging of electric vehicles. Kenya Power Ltd., a distribution utility player in Kenya, is a key stakeholder in the e-mobility ecosystem an is keen on opportunities that can take up extra capacity especially off-peak hence smoothening the load curve, maximizing on the use of transmission and distribution infrastructure as well as exposure to new technology. DC fast charging stations encourage the purchase of electrical vehicles and is one-step closer to a low – carbon economy, using clean transport. A SWOT analysis was used to construct an implementation strategy for EVs charging stations. Financial viability of the project was analysed using payback period, cost-to-benefit ratio, net present value (NPV), and internal rate of return (IRR). The financial indicators suggested that the investment is profitable, hence it is worth to consider it for investment.

Off-design performance analysis of a gas-supercritical carbon dioxide combined cycle under multi-stage mass flow cooperative operation

• A gas-supercritical carbon dioxide combined cycle was employed for load balance. • A reduction coefficient was proposed to build multi-stage mass flow cooperative operation. • Off-design performance models were proposed to present the performance of combined cycle. • Transcritical CO 2 cycle became more important under low-load operating conditions. • The combined cycle had good off-design performance under cooperative operation strategy. Renewable energy power plants have widely installed to supply electrical energy to power grids, which could lead to a grid load-balancing problem owning to the uncertainty of wind and solar power generations. To solve the issue of load balancing, a gas-supercritical carbon dioxide (CO 2 ) combined cycle, which has the advantages of compactness and flexibility, is employed and operated under off-design conditions with load-following operating strategies. A reduction coefficient is assumed to elucidate the multi-stage mass flow cooperative operation strategy of the combined cycle. Furthermore, off-design performance models and a solution procedure are proposed to present the off-design performance of the combined cycle under a cooperative operation strategy. The results from off-design simulations show that a large amount of recovered waste heat ensures that the transcritical CO 2 (t-CO 2 ) cycle becomes more important under low-load operating conditions. Additionally, the power ratio of the t-CO 2 cycle to the cascaded CO 2 cycle can be greater than 90% when the inlet guide vane is closed to the minimum opening, whereas the variation in the efficiency of the cascaded CO 2 cycle is relatively smooth. In general, the gas-supercritical carbon dioxide combined cycle has good off-design performance under multi-stage mass flow cooperative operation in terms of its wide load-following range and remarkably thermal efficiency improvement.

THE EMERGING ROLE OF REPETITIVE TRANSCRANIAL MAGNETIC STIMULATION IN TREATING THE MENTAL CONDITION

repetitive Transcranial Magnetic Stimulation (rTMS) is a form of brain stimulation therapy which is approved by FDA (USA) and CE (Europe). In rTMS treatment, an instrument called a stimulator supplies electrical energy to a magnetic coil that generates a magnetic field in the brain for a short period of time. rTMS is based on the principle of electromagnetic induction that can either stimulate or inhibit the neuronal activity of specific brain areas as per need. This drug free treatment is helpful in many neurological and psychological disorders such as depression, OCD, migraines, autism, ADHD, epilepsy, Bipolar and sexual disorders. The treatment is so safe that it could be conducted on one year old child to an old age. It is an outpatient procedure which does not require hospitalization or anesthesia and entails no memory loss. After the session, patients require no recovery period and are able to go about their daily activities immediately following treatment. Other than some precautions, it is often ideal for patients, because it has none of the side effects of traditional medications and other treatments. It can be said rtms is a focal, non-invasive and very well-tolerated form of brain stimulation in clinical use which is safe for almost all patients suffering from mental or psychological disturbance.

Creating a competitive market for solid biofuels: the role of the electronic trading system and public procurement

The article is a part of a series of works dedicated to the problems of legal regulation of the creation and functioning of the system of electronic trade in solid biofuel as a tool of intensifying the production of biofuel, as well as ensuring sustainable development. Special consideration is given to the issue of participation in the electronic trading system of contracting authorities within the meaning of the Law of Ukraine «On Public Procurement», which requires a clear definition, since the existence of two parallel markets for trading significant volumes of solid biofuel can lead to the leveling of the idea and purpose of creating an electronic trading system. The categories of contracting authorities for which it is expedient to provide the obligation to purchase a set percentage of solid biofuel in the electronic trade system are detailed. It is proposed that such an obligation should be extended to contracting authorities within the meaning of the Law of Ukraine «On Public Procurement» who, due to the special sphere in which they carry out their activities, systematically purchase large volumes of solid biofuel, namely: legal entities in accordance with clause 4, part 1 of article 2 of the Law of Ukraine «On Public Procurement», which carry out activities in the field of ensuring the production, transportation, and supply of thermal and electrical energy to consumers, drinking water, functioning of centralized drainage and meet the characteristics established by the Law. Taking into account the obligations of Ukraine within the framework of the EU-Ukraine Association Agreement, as well as the need to ensure compliance with the Sustainable Development Goals, the feasibility of gradually introducing «green» public procurement of solid biofuel has been proven, taking into account the fact that certain volumes of biofuel will be purchasedby such categories of contracting authorities in the meaning of the Law of Ukraine «On Public Procurement», as state and local government bodies and legal entities that ensure the needs of the state or territorial community, specifically in the public procurement system. The problematicaspects of the registered draft of the Law of Ukraine «On Amendments to Certain Legislative Acts of Ukraine Regarding the Development of Electronic Trade in Alternative Fuels» No. 8052, which is currently under consideration by the Verkhovna Rada of Ukraine, are emphasized.

Rutting Behavior of Asphalt Surface Layers Designed for Solar Harvesting Systems

Solar harvesting systems applied to asphalt roads consist of pipes or coils installed a few centimeters below the asphalt pavement surface. They work thanks to a circulating fluid able to collect the heat coming from solar irradiation of the pavement surface and convert it into thermal gradients that can be used for electric energy supply. Specific attention must be paid to the design of the asphalt mixtures comprising the system. In this sense, the high in-service temperature rutting potential is one of the main issues to be assessed in such applications since the thermal optimization of asphalt mixes could lead to excessively deformable materials. The present study is a part of a wider research area aimed at developing an efficient asphalt solar collector. Here, a laboratory mixture-scale investigation is proposed to verify the anti-rutting potential of specific asphalt layers that were initially designed based on thermal properties only. Repeated load axial and wheel tracking tests are carried out on limestone- and steel slag-based bituminous mixtures. Overall, the tested layers were not fully able to satisfy the permanent deformation acceptance criteria; in this regard, possible improvements in terms of mix constituents and properties are ultimately addressed.