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This paper aims to propose a method for the design of the substation grounding grid in China Fusion Engineering Test Reactor (CFETR). In order to evaluate the safety of the grounding grid, Electrical Transient Analysis Program (ETAP) was used to simulate the fault current, contact voltage, and step voltage, and the results are compared with theoretical calculations to verify the correctness of the design. This will help reduce faults caused by the defects of grounding grid This method is special in that the designed grounding grid not only meets the requirements of relevant standards, but also reduces the number of conductors. During the design process, factors such as voltage level, fault location, and soil resistivity were fully considered to adapt to different occasions. This method can also guide the design and renovation of grounding grids for other buildings in CFETR., (© 2024. The Author(s).)

One of the key challenges in Multi-Spectral Automatic Diagnostic (MAD) robot design is the precise targeting of narrow-angle cameras on a specific part of the equipment. The paper shows that a low-cost MAD robot, whose navigation system is based on open-source ArduRover firmware and a pair of low-cost Ublox F9P GNSS receivers, can inspect the 8 × 4 degree ultraviolet camera bounding the targeting error within 0.5 degrees. To achieve this result, we propose a new targeting procedure that can be implemented without any modifications in ArduRover firmware and outperforms more expensive solutions based on LiDAR SLAM and UWB. This paper will be interesting to the developers of robotic systems for power equipment inspection because it proposes a simple and effective solution for MAD robots' camera targeting and provides the first quantitative analysis of the GNSS reception conditions during power equipment inspection. This analysis is based on the experimental results collected during the inspection of the overhead power transmission lines and equipment inspections on the open switchgear of different power plants. Moreover, it includes not only satellite, dilution of precision, and positioning/heading estimation accuracy but also the direct measurements of angular errors that could be achieved on operating power plants using GNSS-only camera targeting.

Artificial intelligence has demonstrated notable advancements in the realm of visual inspection and defect detection in substations. Nevertheless, practical application presents challenges, with issues arising from the dynamic shooting environment and limited dataset resulting in suboptimal defect identification accuracy and instability. To address these concerns, a pioneering approach based on hybrid pruning YOLOv5 and multiscale data augmentation is proposed for enhancing defect detection in substations. Initially, an enhanced multiscale data augmentation method is proposed. The improved multiscale data augmentation mitigates the impact of the time-varying shooting environment on recognition accuracy and enhances defect detection precision. Subsequently, YOLOv5 is employed for training and detecting defects within multi-scale image data. To alleviate the potential destabilizing effects of YOLOv5's large-scale parameters on model stability, a new model pruning method is implemented. This method strategically prunes parameters to bolster the model's defect identification accuracy. The efficacy of the proposed methodology is evaluated through testing on substation defect images, confirming its effectiveness in enhancing defect detection capabilities., (© 2024. The Author(s).)

The use of information technology and the automation of control systems in the energy sector enables a more efficient transmission and distribution of electricity. However, in addition to the many benefits that the deployment of intelligent and largely autonomous systems brings, it also carries risks associated with information and cyber security breaches. Technology systems form a specific and critical communication infrastructure, in which powerful control elements integrating IoT principles and IED devices are present. It also contains intelligent access control systems such as RTU, IDE, HMI, and SCADA systems that provide communication with the data and control center on the outer perimeter. Therefore, the key question is how to comprehensively protect these specialized systems and how to approach security implementation projects in this area. To establish rules, procedures, and techniques to ensure the cyber security of smart grid control systems in the energy sector, it is necessary to understand the security threats and bring appropriate measures to ensure the security of energy distribution. Given the use of a wide range of information and industrial technologies, it is difficult to protect energy distribution systems using standard constraints to protect common IT technologies and business processes. Therefore, as part of a comprehensive approach to cyber security, specifics such as legislative framework, technological constraints, international standards, specialized protocols or company processes, and many others need to be considered. Therefore, the key question is how to comprehensively protect these specialized systems and how to approach security implementation projects in this area. In this article, a basic security concept for control systems of power stations, which are part of the power transmission and distribution system, is presented based on the Smart Grid domain model with emphasis on substation intelligence, according to the Purdue model. The main contribution of the paper is the comprehensive design of mitigation measures divided into mandatory and recommended implementation based on the standards defined within the MITRE ATT&CK matrix specified, concerning the specifications of intelligent distribution substations. The proposed and industry-tested solution is mapped to meet the international security standards ISO 27001 and national legislation reflecting the requirements of NIS2. This ensures that the security requirements will be met when implementing the proposed Security Baseline., Competing Interests: The authors declare no conflict of interest.

The protection of traditional high voltage capacitor banks relies on an unbalance relay which operates when an internal fuse is blown. However, the unbalance relay cannot indicate cause or position of the fault. Thus, an operator wastes time and human resources investigating the fault issues. To address this issue, a method to locate the fault position in a capacitor bank is developed in this study. The study was simulated by using PSCAD software and modeled on the 115-kV system of the Electricity Generating Authority of Thailand (EGAT). Case studies involving faults with varied phases, side and branch connections, row connections, and inception angles were considered. Moreover, the magnitude and argument of the current phase and unbalanced current were analyzed to identify the fault location in a capacitor bank. The performance of the proposed method was verified via comparison with that of traditional methods and the results of laboratory experiments. In addition, various voltage systems were observed to verify the flexibility and accuracy of the proposed method. The results demonstrate that the proposed method was more efficient than traditional methods at locating the fault position in a capacitor bank., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

Public infrastructure, such as substations, is crucial for the advancement of the economy and society. However, the "not in my backyard" phenomenon is causing concern among the population, and these two things are at odds with one another. This study aims to investigate the driving mechanism that influences participation willingness of the public in order to promote the construction of substations, so the study proposes an integration model based on the planned behavior theory and the normative activation theory. Moreover, a structural equation model is created using the two dimensions, namely, social altruism and personal egoism, while data of 568 questionnaires are used for empirical research in combination with the "Decision-Making Trial and Evaluation Laboratory" method; these data are collected in the surrounding areas of three 110kV substations in Jiaozuo city, China. The key factors that affect participation willingness of the public are discussed, and the study demonstrates that the model is most significantly impacted by public trust, which is an a priori variable. Furthermore, the direct path coefficient of personal norms on participation willingness is the largest, which confirms that increased moral responsibility has a beneficial effect on project execution, and subjective norms contribute to the improvement of the assessment model overall since they are the main variables with the largest centrality degree in the system. The findings of this research better our understandings about the mechanism of "not in my backyard" and offer practical implications for its dissolution. On the basis of this, we present pertinent policy proposals for the "not in my backyard" effect that develops during the construction of public infrastructure., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ma, Li, Guo, Cui, Chen, Xv and Wang.)

Introduction . This research is an attempt to show the role of interior layout of equipment in generating magnetic fields. Materials and methods . The levels of an extremely low-frequency magnetic field were measured in accordance with Standard No. IEEE 644:1994 in three substations and a control building in a petrochemical power plant in southern Iran. Then, workers' occupational exposure (time-weighted average [TWA]) was calculated and the sources of maximum magnetic field generation at each place were identified. Their interior design was changed to achieve the optimal layout of equipment subsequently; the workers' TWA was recalculated for the new situation. Results . The obtained results showed that electrical engineers and technicians were exposed to the maximum TWA of 10.14 μT. The operators in the control room were exposed to the lowest TWA of 0.84 μT. The results also showed that after the change of interior design and proper layout design of the equipment in the substations, the TWA was reduced by 0.73 μT. Conclusion . The research findings revealed that the most harmonious arrangement of equipment in an industrial unit plays a major role in reducing the exposure of workers to magnetic fields and ultimately increases the level of their health in the workplace.

In substations, a localization system based on a wireless sensor network (WSN) is a challenge, because the propagation of the measured signal could be blocked by various devices. In other words, non-line-of-sight (NLOS) propagation, where the signal propagation path is occluded, will affect measurement accuracy. A novel localization method based on a two-step weighted least squares and a probability distribution function is proposed to reduce the influence of NLOS error on the localization result. In this method, the initial multi-group localization result is obtained by the two-step weight weighted least-squares method, and the probability distribution function of the target is constructed by using the initial localization results, which can effectively reduce the influence of the NLOS error on the localization result. The simulation and test results show that the proposed method can keep the coordinate error within 30 cm in the substation. Compared with the localization result of two-step weighted least-squares (TSWLS) method, the average localization error is reduced by more than 1 m. Compared with the other two similar algorithms, the localization accuracy is improved by more than 50%. The tested results show that the localization performance of the method is robustness in the NLOS environment of the substation. While ensuring stability, the proposed algorithm is less efficient than some existing ones. However, under the calculation conditions of ordinary computers, the average single-point calculation time is less than 0.1 s, which can meet the needs of applications in substations.

To separate and locate multi-partial discharge (PD) sources in a substation, the use of spectrum differences of ultra-high frequency signals radiated from various sources as characteristic parameters has been previously reported. However, the separation success rate was poor when signal-to-noise ratio was low, and the localization result was a coordinate on two-dimensional plane. In this paper, a novel method is proposed to improve the separation rate and the localization accuracy. A directional measuring platform is built using two directional antennas. The time delay (TD) of the signals captured by the antennas is calculated, and TD sequences are obtained by rotating the platform at different angles. The sequences are separated with the TD distribution feature, and the directions of the multi-PD sources are calculated. The PD sources are located by directions using the error probability method. To verify the method, a simulated model with three PD sources was established by XFdtd. Simulation results show that the separation rate is increased from 71% to 95% compared with the previous method, and an accurate three-dimensional localization result was obtained. A field test with two PD sources was carried out, and the sources were separated and located accurately by the proposed method.

The use of cardiac pacemakers (PMs) increases in Western countries. The aim of the study is to investigate cardiac pacemakers (PMs) using a human-shaped phantom in magnetic fields of a shunt reactor at a 400 kV substation. We performed seven PM experiments using a phantom. Two locations close to the shunt reactors were chosen. The magnetic field exposure was over 1000 µT in one location and over 600 µT in the other one. The magnetic field exposure did not disturb the tested five different PMs (in unipolar or bipolar configurations). It can be stated that in our experiment, the magnetic field exposure (over 600 µT and over 1000 µT) did not disturb the PMs (in unipolar or bipolar configurations). Since we only studied some PMs, it is possible that the magnetic field exposure at 400 kV substations can cause disturbances to other PMs. However, the risk of disturbances does not seem to be high.