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Contribution: A distinct instructional approach to laboratory activities for power system machines, based on hybrid project-based learning (h-PBL). Students develop their own laboratory procedures and explain their results. This approach creates a positive environment to improve students' problem-solving, and their control design and implementation skills. Background: Prior studies on undergraduate education in electric machines show that power systems control techniques are mostly approached as lectures and simulation tasks, which makes it difficult for students to apply these concepts in real situations. Several studies explored the impact of educational platforms on student learning of various power systems subjects, but further investigation is needed to analyze the influence of the instructional approaches used in applying these educational tools. Intended Outcomes: The h-PBL laboratory activities are intended to foster student learning of power system control by replacing the teacher-led approach with a focus on student-centered real-world applications. This method is also expected to improve student skills in control systems design. Application Design: Students have difficulties implementing power system control techniques in real machines since these are abstract and highly complex. The h-PBL laboratory activities allow students to transition from theory to practice by finding their own solutions to the proposed problems. Findings: The h-PBL laboratory had a positive impact on student learning and grades due to factors that include improving student's critical sense and their problem-solving skills, providing more opportunities for peer-to-peer discussion in group h-PBL activities, and increasing students' interest and motivation to learn through practical engineering applications.

Non-technical losses (NTLs) verified in the power distribution grids cause great financial losses to power utilities. In rural distribution grids, fraudulent consumers contribute to technical problems. The Southern region in Brazil contains more than 70% of the total rice production and power irrigation systems. These systems operate seasonally in distribution grids with high NTL conditions. This work aimed to present an artificial intelligence-based system to help power distribution companies detect potential consumers causing NTLs. This minimizes the challenge of maintaining compliance with current regulations and ensuring the quality of services and products. In the proposed methodology, historical energy consumption information, meteorological data, satellite images, and data from energy suppliers are processed by artificial intelligence, indicating the suspicious consumer units of NTL. This work presents every step developed in the proposed methodology and the tool application in a pilot area. We detected a high number of consumers responsible for NTLs, with an accuracy of 63% and an average reduction of 78% in the search area. These results corroborated the effectiveness of the tool and instigated the research team to expand the application to other rice production areas. [ABSTRACT FROM AUTHOR]

On average, 70% of the world's freshwater is used in agriculture, with farmers transitioning to electrical irrigation systems to increase productivity, reduce climate uncertainties, and decrease water consumption. In Brazil, where agriculture is a significant part of the economy, this transition has reached record levels over the last decade, further increasing the impact of energy consumption. This paper presents a methodology that utilizes the U-Net model to detect flooded rice fields using Sentinel-2 satellite images and estimates the electrical energy consumption required to pump water for this irrigation. The proposed approach involves grouping the detected flooded areas using k-means clustering with the electricity customers' geographical coordinates, provided by the Power Distribution Company. The methodology was evaluated in a dataset of satellite images from southern Brazil, and the results demonstrate the potential of using U-Net models to identify rice fields. Furthermore, comparing the estimated electrical energy consumption required for irrigation in each cluster with the billed energy values provides valuable insights into the sustainable management of rice production systems and the electricity grid, helping to identify non-technical losses and improve irrigation efficiency. [ABSTRACT FROM AUTHOR]

The IEC 61850 standard aims at digitization substations and provides interoperability between various Intelligent Electronic Device vendors. The digitization process is accompanied by several challenges related to data transmission on the ethernet network and the protection behavior under these conditions. Among the challenges, we can mention packet loss, delay, and duplicate frame, which occurs when the merging units (publisher) transmit the sampled values and, for some reason, these packets do not reach the subscriber or are duplicated. Nowadays, most Intelligent Electronic Device manufacturers block the protection function when some sampled value packets are corrupted. The effects of blocking protection when packet loss occurs under normal operating conditions do not cause significant problems. However, when a fault occurs, the corrupted packets can cause a delay in fault clearance, causing even more damage to the grid. The purpose of this article is to present the effects of corrupted sampled values on the performance of overcurrent protection. All the evaluations were performed in real time using the hardware-in-loop simulation approach with a commercial Intelligent Electronic Device. The OP5700 hardware platform from OPAL-RT, with the library "IEC 61850 Data Integrity Manipulation", was used. The results show that corrupted sampled value frames affect the functioning of the protections. [ABSTRACT FROM AUTHOR]

The occurrence of an electric arc is an inherent possibility when working in a live line. Thermal risk is considered one of the most relevant risks associated with this type of event, so every worker who performs daily activities in the electricity distribution sector is subject to this risk to a lesser or greater degree. The quantification of the thermal risk is based on estimating the energy generated by the electric arc, and focuses on a surface called incident energy. Therefore, the incident energy estimate is used to define thermal protection strategies applicable to workers who carry out activities in the distribution sector. In light of this, the present work proposes a review of incident energy estimation methods for electric arcs in electric power distribution grids, highlighting the applicability of each of these methods in terms of voltage, short circuit type, and environment. Finally, five case studies are presented in which adequate methods are used to estimate the incident energy. Their results concerning incident energy and selected protective equipment (PPE) are compared. From the review of existing incident energy estimation methods in the literature and the case studies presented, the importance of selecting a suitable method for the type of system analyzed, considering electric, spatial, and intervention aspects, is observed. Finally, considering that the primary objective of incident energy estimation is to determine the need and selection of arc-rated PPE, the selected estimation method must be aligned and integrated with the clothing selection procedures and applicable PPE. [ABSTRACT FROM AUTHOR]

The quality of electricity is one of the most discussed issues in the regulatory context, structured by guidelines that allow the assessment of efficiency in electricity supply. Regarding electricity distribution systems, it is essential to highlight the aspects associated with the definition of continuity indicators to measure the service provided by the utilities. The parameters used to calculate the indicators are set by specific agencies in each country based on studies and their characteristics. With the growth in demand for electricity, debates associated with reducing greenhouse gas emissions in the atmosphere, and the increase in Distributed Energy Resources (DERs) connected to the grid, a new trend related to the energy supply is verified. Given these new scenarios, this paper presents a literature review in the regulatory field of existing distribution systems in South American countries. The research proposes to analyze, compare, and expose the current models to evaluate their methods and indicators, including a complete case study in Brazil. This paper seeks to illustrate and point out perspectives, challenges, and future perspectives through the collected and analyzed data. [ABSTRACT FROM AUTHOR]

This paper presents the development and application of an experimental and educational platform for operation testing of synchronous machines and power system regulators. This platform is composed by an asynchronous motor, which simulates the primary machine, that is coupled to a synchronous generator shaft. The platform also includes a supervisory and control system, which acts on the parameterization of the regulators and drives the primary machine and generator's excitation field. It is possible to carry out operation tests with the generator stator running in open circuit, stand-alone or connected to the grid, and to simulate disturbances in the system to observe the power system behavior and control performance in such cases. The main contribution of this research is a real platform for experimental validation of digital models of automatic voltage regulators, power system stabilizers and governors, consequently optimizing control design and parameterization. Regarding to the teaching in power system control, the differential of this platform is the unified approach of theory understanding with the comprehension of techniques for implementation of control and instrumentation in real systems, thus contributing to the improvement of student learning, professional formation and motivation for practical activities. [ABSTRACT FROM AUTHOR]

Summary: Transient stability in distribution systems has gained special interest because of the continuous increase of distributed generation connected to the grid. Besides the dynamic behavior of the generation system, the distribution networks present extensive branches and unbalanced loads with a specific set of equipment, what increases the complexity of the numerical analysis of transient stability. In this context, this work proposes a new methodology for transient analysis in distribution networks with distributed generation, which is divided in 3 major steps: (1) the representation of the network model through a simplified model, (2) the selection of disturbances types and buses for application, and (3) and the adjustment of stability control systems. The methodology is suitable for unbalanced networks and a demonstration of a single‐pole switching is presented. Some case studies were simulated and analyzed for a real network model. [ABSTRACT FROM AUTHOR]

Continuity in power supply for the consumers is a permanent concern from the utilities, pursued with the development of technological solutions in order to improve the performance of network restoration conditions. Using remotely controlled switches corresponds to one possible approach to reach such an improvement and gives some convenient remote resources, such as the fault detect, isolation, and transfer loads. This paper presents a methodology implemented in a computer programming language for allocation of these devices in electric distribution systems based on the analytic hierarchical process (AHP) method. The main contributions focus on considering the impact of installing remotely controlled switches in the reliability indices and the AHP decision-making algorithm for the switches allocation. The effectiveness of the proposed algorithm is demonstrated with case studies involving actual systems of the AES Sul utility located in Southern Brazil. [ABSTRACT FROM AUTHOR]

• Dynamic network reconfiguration heuristic after contingency situations. • Reconfiguration for multiple time periods and multicriteria decision making process. • Distributed generations operating in both grid-connected and islanded modes. This paper presents a decision-making model for the dynamic reconfiguration of distribution networks after contingency situations based on formulations of the self-healing problem with islanding. This paper develops a three-stage algorithm. The first stage applies a greedy reconfiguration heuristic, which calculates the criteria values for each viable network configuration in each hour. To address the variety of criteria, the analytic hierarchy process method is applied to define the weights. The second stage addresses the problem statically to reduce the number of configurations and, therefore, the combinations of step 3. In the third stage, the problem is approached dynamically, generating the optimal sequence of topologies for the analyzed period, while considering the time-varying operational conditions of the system. The proposed heuristic significantly reduces the complexity of the problem while minimizing the following criteria: energy not supplied, losses, number of interrupted consumers and switch operations. The physical constraints of the power grid considered in the proposed model are the line limits, protective equipment settings, voltage limits, distributed generators (DG) limits and network radiality. The proposed model is analyzed in different scenarios in the IEEE 123-bus system, modified with the insertion of DGs. The proposed method is compared with a conventional benchmark model. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a new probabilistic model for active low‐voltage prosumers suitable for distribution expansion planning studies. The load uncertainty of these consumers is considered through a range of load profiles by segmenting the energy consumption according to the different energy uses. Then, consumption adjustments are simulated using a nonhomogenous Poisson process based on the energy usage preferences and the financial gains according to the tariff scheme. A case study based on the modified IEEE 33‐Bus test system with real data collected from a Brazilian distribution company is performed in order to analyze the impact of the load profiles in scenarios with high penetration of renewable distributed generation (DG). The experiments carried out reveal that considerable monetary savings in the expansion of the distribution grid can be achieved for this case study (up to 37%) as compared with the alternative with no active demand (AD) by exploiting the flexibility associated with the active behavior of prosumers as a response to price signals and/or by permitting adequate levels for the integration of DG into the distribution grid. [ABSTRACT FROM AUTHOR]

Highlights • Matheuristic for emergency response in electric distribution system with islanding. • Cost impact analysis of islanded customers in a time-function. • MILP model of the emergency order scheduling problem with islanding operation. • Validation on the IEEE 33-bus system, modified with the insertion of DGs. Abstract Since power supply may suffer interruptions, caused by climate events or even due to equipment and human failures, these interruptions are associated with procedures commonly referred as emergency orders. These emergency orders must be attended by repair crews in an attempt to reestablish the power supply all over the system. Assuming a set of these emergency orders, the network operation center (NOC) must find a scheduling so that they are all attended by the repair crews and the power supply reestablished as soon as possible, while considering the minimization of the total service cost. Distributed generation (DG) may be one alternative for furnishing temporally power supply, such as photovoltaic and wind power generation sources. In such approach, the islanding operation confers such a complexity when considering how much time should be needed to supply the affected loads and which ones may be even selected. This study proposes a novel matheuristic for emergency response to the contingency planning problem related to electric distribution operations, considering unforeseen islanding of DG. From using a mixed integer linear programming (MILP) model, based on the emergency order scheduling problem (EOSP) with islanding operation formulations, the optimization criteria involves the minimization of the cost of non-supplied energy and the penalties related to high important customers, while respecting electrical constraints. Computational results on the IEEE 33-bus system, modified with the insertion of DGs, show the effectiveness of the proposed solution on reducing the total attendance cost when compared to a traditional scheduling solution without considering the islanding operation. [ABSTRACT FROM AUTHOR]

This paper proposes a new approach to the development of coordinated Volt/VAr control for real-time operation of smart distribution grids. The methodology intended for the coordinated Volt/VAr control conveys the minimization of the voltage violations and also a better distribution of the number of commutations among the control equipments. The control algorithm developed centrally coordinates the equipment actions in the conditions where the local control does not act properly. The adjustments are performed in the voltage regulator, in the capacitors banks and in the reactive power injected by the inverters of the distributed generation. The coordinated control strategy uses the fuzzy logic combined with a heuristic algorithm, which has implementation simplicity and suitable performance for real-time applications. A numerical example is presented aiming to clarify the procedure of the proposed control algorithm. Furthermore, the algorithm performance is verified through a modified IEEE 34 node test feeder under distinct operating conditions. [ABSTRACT FROM AUTHOR]