Search

The papers address the following key areas: ' B I Applications of IoT and digital twin in electrical power systems: A comprehensive survey i b ': This research paper reviews the applications of the Internet of Things (IoT) and digital twin technology in electrical power systems. With the growth of Internet of Things (IoT) techniques, applications have become smarter, and linked gadgets allow them to be used in many parts of power systems. ' B I A new low-cost and low-power industrial Internet of Things infrastructure for effective integration of distributed and isolated systems with smart grids i b ': This research paper provides an Internet of Things (IoT) infrastructure solution based on a newly designed low-cost microcontroller-based IoT remote terminal unit (RTU) to integrate new, old, and conventional sites of existing grids with smart grids. [Extracted from the article]

This article discusses the role of power electronic converters in smart grids and electric vehicle applications. The authors highlight the technical connection between renewable energy, smart grids, energy storage, and electric vehicles. The special issue includes twelve accepted papers that cover topics such as high gain DC-DC converters, power converters for electric vehicle and motor drive applications, and power system applications. The papers present various novel topologies and control techniques, indicating the rapid growth and future potential of power converters in these fields. The authors express their appreciation to the contributing authors and anonymous reviewers for their valuable contributions to this special issue. [Extracted from the article]

This paper proposes a new DC–DC bipolar resonance converter that combines a dual‐active‐bridge and a multi‐port resonance Buck‐Boost converter. This structure uses a resonance network between the input and output ports, which has the following advantages: it creates a constant current supply in the open‐loop mode; it keeps the current phase of the output ports constant under different loads; and it allows reversing the power from any output port by adjusting the phase shift of its switches, if the converter is connected to a DC microgrid. In this way, power can be exchanged among each of the output ports and input ports. The advantages of this converter are bidirectional power exchange, power exchange between output ports, soft switching, high efficiency, integration of transformer parasitic elements, and the modular capability to connect multiple resources at the input. Furthermore, the proposed structure of the bipolar converter has been implemented for verification purposes, and its results are presented in three modes: open loop, voltage control, and current control. Additionally, the results of different modes of power sharing and their bidirectionally are shown. [ABSTRACT FROM AUTHOR]

Solar photovoltaic energy is a vital renewable resource because it is clean, endless, and pollution‐free. Due to the fast growth of the semiconductor and power electronics sectors, photovoltaic (PV) technologies are climbing significant attention in modern electrical power applications. Operating PV energy conversion systems at the maximum power point is essential for getting the maximum power output and raising efficiency. This paper proposes a regression‐based Perturb and Observe method to quickly find a global maximum power point, avoiding being stuck in local maxima, likewise analytical and metaheuristic methods. The improved control focuses on the narrowed search areas by linear and non‐linear regression analyses using the generated PV model on a flexible Python environment. Furthermore, the method's accuracy is validated in real time under variable temperatures, irradiations, and loads. This method was proven with a hardware implementation. The proposed method is more than 98% accurate and can withstand long‐term modelling. The suggested regression‐based perturbation and observation method provided a short learning time and easy implementation. Additionally, the dynamic recorded results can be visualized for researchers to utilize efficiently. [ABSTRACT FROM AUTHOR]

Uncertainty analysis deals with the fluctuations and unpredictability of the electrical power generated from renewable resources (RRs), such as solar PV and wind energy systems. This paper gives an insight into various techniques used for the uncertainty analysis and a probabilistic Monte Carlo Simulation is applied for modelling the uncertainties concerned with RRs and electric vehicle (EV) load in the MATLAB platform. The uncertainty associated with the price sensitivity of EV charging and the state of charge of EVs is taken as a prime factor for analysis in the present work. Despite the fluctuations and unpredictability of electricity generation and consumption, the considered system ensures that the total amount of electricity supplied by solar PV, wind and grid matches the total amount of electricity demanded by EV load. Rao‐1, Rao‐2 and Rao‐3 algorithms are applied in this work to optimize the operation cost of charging stations under uncertain conditions and without any uncertainties. The results obtained without uncertainties by Rao algorithms are compared with the existing particle swarm optimisation method. In the presence of uncertainties, Rao‐1 and Rao‐2 algorithms are compared with Rao‐3 and it is found that the Rao‐3 algorithm performed better. [ABSTRACT FROM AUTHOR]

This paper presents the development of an Air‐Cored Axial Flux Permanent Magnet Generator (ACAF PMG) integrated for direct battery charging scheme for urban and rural micro‐wind turbine applications rated at 1 kW. The proposed generator has a Single Stator Double Rotor configuration with a relatively short axial length. In this paper, the analytical model for generator sizing is presented and the main parameters are defined. Novel analytical model is presented to determine the required number of turns for each phase in order to produce a balanced voltage in the three phases. The generator is electromagnetically analyzed using Finite Element model and simulated using Matlab/Simulink to predict its performance under several operating conditions. The effect of retainment ring type on the generator performance is also demonstrated. The machine is harnessed to a battery bank via a three‐phase fully controlled converter using six bridge thyristors to regulate the output voltage delivered from the generator to the battery. Generator model and simulation results are validated via experimental tests. The preliminary experimental results showed a good match with the simulation results. Moreover, the proposed machine is compared favourably with other counter machines of similar configuration and power ratings in terms of machine size, power‐to‐weight ratio, and voltage regulation. This paper therefore demonstrates the concrete benefits of utilizing the axial flux PMG in scavenging energy to generate electrical power from micro wind turbines. [ABSTRACT FROM AUTHOR]

This paper reviews the applications of Internet of Things (IoT) and digital twin technology in electrical power systems. It begins by discussing the generalized IoT value chain, followed by the terminology of smart grid, with clarifying the role of IoT‐systems and the digital twin structure within the Smart Grid. A comparison between different short‐range and long‐range transports is presented. The paper then discusses the use of IoT and digital twin technology for effective energy management with applications in smart homes, smart buildings, smart grids, smart industries (Industry 4.0), smart transportation and smart cities. Additionally, the paper explores the use of IoT and digital twin technology for condition monitoring and diagnosis (CMD) in electrical power systems. Three different cases are presented for CMD, that is, CMD of power transformers, CMD of electrical grids and CMD of substations. IoT and digital twin applications are also highlighted in power electronic systems. Finally, the paper discusses the challenges and opportunities of applying IoT and digital twin technology to electrical power systems and provides recommendations for future research. [ABSTRACT FROM AUTHOR]

Summary: Autonomy is becoming a prime requirement for satellite mission control operations. Data‐driven methods like Machine Learning models are playing a key role in bringing in autonomy. Health keeping data from satellite telemetry is a key ingredient in these data‐driven methods. In real‐world satellite operations, the health‐keeping telemetry data gradually drifts due to adverse space weather effects and wear and tear of electronic and mechanical components. The key question that arises is how to detect and quantify the data drift which is generally a gradual phenomenon. This paper discusses a novel statistical method for detecting data drift occurring in satellite telemetry. For the purpose of experimental work in this paper, an actual telemetry data set of the BUS CURRENT sensor which is part of the Electrical Power System of a Low Earth Orbit Satellite was considered. Data drift detection test was carried out using this sensor data using the developed novel statistical method and with Kolmogorov Smirnov test which is a probabilistic method. Both results are analysed and compared. Thereafter novel statical method was used to check its efficacy using a synthetic data set with induced drift. [ABSTRACT FROM AUTHOR]

Large geomagnetic storms are a space weather hazard to power transmission networks due to the effects of Geomagnetically Induced Currents (GICs). GIC can negatively impact power transmission systems through the generation of even‐order current and voltage harmonics due to half‐cycle transformer saturation. This study investigates a decade of even‐order voltage total harmonic distortion (hereon referred to as Even‐Order Total Harmonic Distortion (ETHD)) observations provided by Transpower New Zealand Ltd., the national system operator. We make use of ETHD measurements at 139 locations throughout New Zealand, monitored at 377 separate circuit breakers, focusing on 10 large geomagnetic disturbances during the period 2013–2023. Analysis identified 5 key substations, which appeared to act as sources of ETHD. The majority of these substations include single phase transformer banks, and evidence of significant GIC magnitudes. The ETHD from the source substations was found to propagate into the surrounding network, with the percentage distortion typically decaying away over distances of 150–200 km locally, that is, at a rate of −0.0043 %km−1. During the study period some significant changes occurred in the power network, that is, removal of the Halfway Bush (HWB) single phase bank transformer T4 in November 2017, and decommissioning of the New Plymouth substation in December 2019. Decommissioning of these two assets resulted in less ETHD occurring in the surrounding regions during subsequent geomagnetic storms. However, ETHD still increased at HWB with increasing levels of GIC, indicating that three phase transformer units were still susceptible to saturation, albeit with about 1/3 of the ETHD percentage exhibited by single phase transformers. Plain Language Summary: Space weather, triggered by solar storms, can lead to significant variations in the Earth's magnetic field. The magnetic variations are termed geomagnetic disturbances. Changing magnetic fields induce electric fields at the Earth's surface, causing unwanted currents to flow in electrical power transmission networks. These Geomagnetically Induced Currents (GICs), pose a hazard to network operations as they can cause networks to become destabilized, leading to blackouts and damage to transformers. One negative impact of GIC in a power network is the production of harmonics of the power transmission frequency (typically 50 or 60 Hz); such harmonics contributed to the blackout of the Québec power system in March 1989. In our paper we study harmonic distortion occurrence in the New Zealand power grid using measurements from 139 substations across the country during 10 geomagnetic storms. Analysis identified 5 key substations, which appeared to act as sources of harmonic distortion. The majority of these substations include a particular transformer design which is known to be more susceptible to GIC issues, as well as evidence of significant GIC. Key Points: A decade of even‐order harmonic distortion data are used to investigate the impact of space weather on a power networkIn New Zealand four key substations containing single phase transformers act as sources of enhanced harmonic distortionThe harmonic distortion is found to propagate into the nearby power network over 150–200 km distances, decaying at a rate of −0.0043 %km−1 [ABSTRACT FROM AUTHOR]

This paper deals with the control and performance improvement of parallel-operated voltage-source inverters (VSIs) controlled as virtual synchronous generators (VSGs). In publications regarding the parallel-operated VSGs, transmission lines are considered to be mainly inductive. However, less analytical works have been done regarding the control of paralleled VSGs in low-voltage grids with dominant resistive impedances. Once VSIs are controlled as VSGs in a microgrid with more resistive transmission lines, swing equation and system representation for the power-angle synchronization will change leading to a new control structure. Therefore, this paper deals with the control of parallel-operated converter-based VSGs in low-voltage grids with dominant resistive line impedances. In this way, the VSG representation, comprising the swing equation and V-P droop characteristic, for applications in highly resistive microgrids is presented, in which the swing equation and VSG frequency are related to reactive power. Then, the V-P droop characteristic is modified and an enhanced P-V droop characteristic for proper sharing of active power between the VSGs in highly resistive microgrids is proposed. Next, the VSG control is modified so that the R/X ratio at the VSG output increases and thus the decoupled control of active/reactive powers in relatively inductive cases is realized as well. [ABSTRACT FROM AUTHOR]

For ultra‐high‐voltage (UHV) systems together with high‐voltage facilities, more rationalized insulation coordination and equipment design are required. To this end, making large‐scale and long‐term field lightning‐strike observations, large amount of and practical experiments, and introducing new analysis techniques have enabled the development of advanced technologies capable of transforming conventional techniques. This paper reviews what has been developed in a Japanese electric power company in this regard. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

It has been reported that electrical engineering schools might be facing a decline in newly enrolled students combined with an increase in the number of dropouts due to motivation and engagement problems. At the same time, companies in the electric power industry require safe and realistic training environments for their trainees to reduce induction program times, costs, and accidents. Game‐based learning (GBL) applications offer alternatives in both sectors, that is, education and training, for increasing engagement, motivation, and knowledge transfer in controlled environments. This paper aims to show applications of GBL techniques towards educational and training objectives in electrical power and energy systems in the period spanning from 2002 to 2021. This review points to two main research questions: what GBL tools have been used for education and training purposes in electrical power and energy systems during 2002 to 2021? Also, what are the methodologies used for assessing the efficacy of using GBL applications in electrical power and energy systems? A structured review methodology was applied to identify how GBL has been used in electrical power and energy systems. A total of 81 papers were selected for full review. The procedure included the formulation of research questions, identification and selection of studies, and data synthesis of results. Our review showed that most GBL applications in electrical power and energy systems were developed with education purposes (63%), from which 29% used graphic user interfaces and 23% used serious games. On the other hand, for training purposes, the most popular GBL tool was virtual reality, applications of which were discussed in 56% of the reviewed papers. The review also showed that only 42% of the education papers and 37% of the training papers performed learning efficacy analyses; in which qualitative postevaluations or postsurveys were the most popular methodologies used in over 50% of those papers. [ABSTRACT FROM AUTHOR]

Electric power generated by photovoltaic (PV) systems is generally unstable because of uncertain meteorological conditions. Stably maintaining the supply‐demand balance of power systems requires an accurate prediction of the performance of PV systems. Especially for predicting the performance of the PV systems containing modules with different electrical characteristics or installed in different angles, it is necessary to calculate the generated power of the system by combining the current‐voltage (I‐V) characteristics of each module in series and parallel. Therefore, an accurate method is required for estimating the I‐V characteristics in various meteorological conditions. In this paper, a simple modeling method of the I‐V characteristics for crystalline silicon PV modules is proposed. The I‐V characteristics can be simulated in a good accuracy for practical use based on a simplified equivalent circuit of PV modules and a temperature correction of the short‐circuit current, open‐circuit voltage, and the current and voltage at maximum power point. The validity of the proposed method is examined by comparing simulated and measured I‐V characteristics of a PV module. Furthermore, to demonstrate the effectiveness of the proposed modelling method, it was applied to simulating the power generation of a PV system containing modules installed in different angles. [ABSTRACT FROM AUTHOR]

The electric industry is developing towards a more efficient, reliable, and resilient electric power network. In this way, utilizing distributed energy resources (DERs), especially renewable DERs (RDERs) are a paradigm change. DERs offer many advantages in power systems, including transmission loss reduction, environmental benefits of RDERs, and enhancement of security, reliability, and resiliency of the network. However, high penetration of DERs increases uncertainty and challenges the efficient and reliable operation of the power system. This paper provides a thorough review of the transactive distribution platform which is essential to address the aforementioned challenges. This distribution platform includes a transactive distribution system operator providing a seamless and coordinated control to dynamically balance supply and demand and follow uncertain generations of RDERs. Indeed, this review paper highlights the capability of transactive energy (TE) by considering its key aspect in providing energy sharing opportunities for the integration of DERs into smart grids (SGs). TE is acombination of economic and control methods that enable optimum, reliable, sustainable, and efficient operation of SGs. Furthermore, a fully transactive framework offers more choices for DERs to control and manage the energy transactions in the retail market, as well as improves the inter operability among various market players. [ABSTRACT FROM AUTHOR]

Unit commitment (UC) stands out as a significant challenge in electrical power systems. With the rapid growth in power demand and the pressing issues of fossil fuel scarcity and global warming, it has become crucial to enhance the utilization of renewable energy sources. This study focuses on addressing the UC problem by incorporating a wind farm and proposes a modified version of the metaheuristic African vultures optimization algorithm (AVOA) in binary form, utilizing the sigmoid transfer function. The modified AVOA employs multiple phase‐shift tactics to overcome premature local optima. By determining the on/off status of generating units, the modified AVOA improves the algorithm's effectiveness. Additionally, the paper develops an auto‐regressive moving average model (ARMA) to forecast wind speeds, with the AVOA assisting in selecting the optimal orders (q and p) of the ARMA model. This is done using historical wind speed data to capture uncertainty in the wind speed. The wind power is then calculated using various models and integrated into the UC problem. The effectiveness of the modified AVOA is examined on the IEEE 30‐bus system. The binary AVOA (BAVOA) outperforms several algorithms presented in the case study, demonstrating its superiority. Furthermore, the results indicate that BAVOA delivers superior outcomes within the discrete search space when compared to the continuous search space. [ABSTRACT FROM AUTHOR]

Photovoltaic technology enables the direct conversion of solar energy into electrical energy. Model studies have a very crucial place in the implementation of PV systems. Electrical efficiency decreases with increasing PV panel temperature. So, solar panel temperature is an important parameter that needs to be reduced to obtain a better energy efficiency from PV panels. In this study, the aim is to develop a simple method that can estimate the temperature of a solar panel. It can utilize different methods to obtain the thermal responses of a PV panel. In this study, a modeling study was carried out to find panel temperature, efficiency and power values under transient ambient conditions. As a simpler approach, "lumped system analysis" method was used. The model developed in this study can simulate the thermal performance of the PV panel under transient conditions. After the model is defined for a particular PV panel, the required inputs are; total incident solar radiation, wind speed and ambient temperature. The results obtained from this model were compared with existing modeling and experimental studies in the literature. With the simulation using the model developed in this study, panel efficiency, temperature and panel electricity power were calculated using instantaneous environmental data for the selected Konya and Sanliurfa (Turkey) regions. In this paper, it was obtained that the wind speed increased the PV panel efficiency, while the ambient temperature decreased it. Depending on the increase in wind speed (1–2 m/s), the increase in PV panel electric power is 3.7%, while the increase in high wind speeds (5–6 m/s) decreases to 0.77%. It was found that a 7°C increase in ambient temperature caused a 4°C increase in PV panel temperature and a 1.5% decrease in PV electrical power generation. The PV panel electrical power values calculated using the efficiency values calculated according to the daily average environmental temperatures were found to be 13% higher than the power values calculated using instantaneous environmental temperatures. If this difference is not taken into account in the calculation of economic payback periods, it will lead to significant erroneous results. The importance of transient simulations of the PV panel has been demonstrated by the calculations. [ABSTRACT FROM AUTHOR]

Background: 2022 marks a decade since the profession of podiatry secured independent prescribing rights in the UK. Widely viewed as a significant milestone, its advent appeared to herald a new age of practice, with increased autonomy, a broader scope of practice and improved patient care. Access to any medicine within the British National Formulary (with a few notable exceptions) seemed to signal an end to the perennial difficulties and frequent disappointments in obtaining ease of access to medicines necessary for effective practice. Main body: Recent attempts to expand the scope of prescribing practice to include access to a broader range of controlled drugs (CDs) have led to unanticipated complications which may even threaten existing rights. These issues highlight the limitations of current independent prescribing and the continuing inability of podiatrists to access certain key medicines, primarily controlled drugs. Reliance on specified 'lists' of approved medicines, whether a controlled drug list for prescribers or the use of statutory exemptions by non-prescriber podiatrists, remain inflexible and difficult to change. The data underpinning much of this paper is derived from the work undertaken by the authors as representatives of podiatry on NHS England's Chief Professions' Officers' Medicines project, in particular involving submissions to the Commission on Human Medicines and the Advisory Council on the Misuse of Medicines, spanning the years 2017–2021. It describes a complex process, and highlights a misalignment between two legislative frameworks that threaten to unravel existing rights. Short conclusion: Ongoing difficulties relating to controlled drugs illustrate the problematic nature of current supply, administration and prescribing rights in podiatry. Efforts to keep pace with periodic legal reclassifications of medicines are constrained by limited and inflexible legal mechanisms, and formal approval for extended access via prescribing remains unpredictable and complex. For prescriber and non-prescriber1 (1Non- prescriber podiatrists are those who are neither supplementary or independent prescribers, but do enjoy existing administration and supply rights to certain medicines.) podiatrists alike, the profession of podiatry faces a new challenge to its ability to access medicines, and to realise its full clinical potential. [ABSTRACT FROM AUTHOR]

Spacers in the compact power distribution network are essential components for the support, organization, and spacing of conductors. To improve the reliability of these components and have an optimized network design, it is necessary to evaluate the performance of the variation of their geometric parameters. The analysis of these components is fundamental, considering that there are several models available that are validated by the electric power utilities. Due to the various possible design shapes, it is necessary to use an optimized model to reduce the electric potential located in specific sites, improving the reliability in the component, as the higher electrical potential results in a greater chance of failure to occur. The finite element method (FEM) stands out for evaluating the distribution of electrical potential. In this paper, an FEM is used to evaluate variations in vertical and horizontal dimensions in spacers used in the 13.8 kV power grid. The models are analyzed in relation to their behavior regarding the potential distribution on their surface. From the results of these variations, the model is optimized by means of a mixed‐integer linear problem (MILP), replacing the FEM output with a ReLU network substitute model, to obtain a spacer with more efficiency to be used in semi‐insulated distribution networks. [ABSTRACT FROM AUTHOR]

To ensure the robustness of both civilian and military infrastructure, it is important to protect electric power grids, smart grids, and other electrotechnologies from known and possibly as‐of‐yet unknown space weather hazards. Space weather can generate intense geoelectric fields at the surface of the Earth, as well as large voltage gradients across long distances of the Earth. These voltage gradients can lead to geomagnetically induced currents (GICs), which are known to produce hazards to electric power grids. The finite‐difference time‐domain (FDTD) method is a powerful and versatile method that has already been applied to the study of geoelectric fields. The advantages of FDTD over other methods are that it can account for more geometrical complexities and realistic time waveforms and that it directly solves for geoelectric fields. Snell's Law predicts that any electromagnetic waves incident on the ground should essentially propagate straight downwards into the low resistivity ground. For this reason, vertical FDTD grid resolutions of 1/3 of a skin depth were usually chosen, while the horizontal grid resolution was relaxed. We find, however, that there is another important consideration for choosing an FDTD grid resolution applied to real‐world scenarios: localized field variations due to currents generated by ground features. It turns out the grid resolution requirements are much stricter when taking this physics into account. Key Points: Previous FDTD models limited the vertical resolution to <13 ${< } \frac{1}{3}$ of a skin depth but relaxed the horizontal resolution for efficiencyThis paper shows that there is another important consideration: localized field variations due to currents generated by ground featuresWe find that the required vertical and horizontal resolution requirements are higher for realistic scenarios than previously thought [ABSTRACT FROM AUTHOR]

Summary: Dual‐inverter‐driven open‐end winding brushless direct current motor (OEWBLDCM) drives are amenable for the implementation of some interesting fault‐tolerant features, which could find useful applications in low power electric vehicles (EVs). The power semiconductor switching devices in the dual‐inverter system are vulnerable to the development of open‐circuit faults (OCFs) and the short‐circuit faults (SCFs). This paper investigates the possibility of imparting complete fault‐tolerant capability to EVs, which employ OEWBLDC motors for propulsion. With the proposed dynamic post‐fault reconfiguration of the power circuit and the reconnection of the battery banks, it is possible to deliver the rated (i.e., 100%) post‐fault output power to the BLDC motor, despite the failure of a power semiconductor switching device (because of either an OCF or an SCF) in the dual‐inverter system. The feasibility evaluation of the proposed fault‐tolerant drive reveals that the aforementioned objectives are realizable at an affordable hike in the raw material cost of the propulsion system. Simulation studies and Experimental verification on a laboratory prototype validate the proposed fault‐tolerant OEWBLDCM drive. [ABSTRACT FROM AUTHOR]

Waste heat recovery (WHR) system uses the thermal energy from the exhaust gases of an internal combustion engine (ICE) to assist in the electricity generated by the ICE generator in buildings. This paper presents a model predictive control (MPC) framework to minimize the fuel consumption of an ICE by integrating it with a WHR system. To this end, a control oriented model of a WHR system is developed and then integrated to a control oriented model of a turbocharged dual fuel diesel‐natural gas ICE. The ICE model is derived based on experimental data collected from a 6.7 L Cummins ISB engine modified for dual fuel operation. The designed MPC framework optimizes the ICE combustion, turbocharger, and organic Rankine cycle (ORC) system in the WHR to minimize fuel consumption of the ICE. The designed control framework also allows to meet time‐varying exhaust gas temperature requirements of the ICE to meet exhaust emission constraints. The results show that the optimal operation of the WHR and the ICE reduces the fuel consumption of the ICE by 6.7%. [ABSTRACT FROM AUTHOR]

The American College of Clinical Pharmacy (ACCP) supports the completion of residency training as a prerequisite for direct patient care responsibilities. The current supply of pharmacy residency opportunities, however, does not match the demand, causing many graduates to enter the workforce directly after completing their pharmacy school training. Many pharmacists may then desire to transition into a clinical position leveraging the versatility of the Pharm.D. degree and the expanding opportunities in the profession. Without residency training, however, these candidates may be disadvantaged or find it difficult to justify their experience matches that of their residency‐trained colleagues for a clinical pharmacist position. The college recognizes the usefulness of and potential need for a pharmacy residency equivalency to assist both pharmacists seeking further advancement and employers recruiting clinical pharmacists to provide direct patient care. The pharmacy residency equivalency should be standardized and demonstrate achievements in clinical pharmacist competency areas. This white paper from the ACCP Publications Committee provides updated considerations for components of a standardized pharmacy residency equivalency. [ABSTRACT FROM AUTHOR]

The unmanned aerial vehicle formation plays a crucial role in numerous applications, such as reconnaissance, agricultural plant protection, and electric power inspection. This paper provides a comprehensive review and analysis of the unmanned aerial vehicle swarm communication networks and formation control strategies. First, the most commonly used unmanned aerial vehicles are introduced and compared. Next, the entire process of the formation task, from the formation assignment to the formation transformation, is detailed described. At last, the widely adopted communication networks are analyzed, and the existing formation control strategies of the UAV swarm are compared, which shows that the distributed formation control is superior to the centralized method and is the future development trend. [ABSTRACT FROM AUTHOR]

Previous statistical studies of plasmaspheric hiss investigated the averaged shape of the magnetic field power spectra at various points in the magnetosphere. However, this approach does not consider the fact that very diverse spectral shapes exist at a given L‐shell and magnetic local time. Averaging the data together means that important features of the spectral shapes are lost. In this paper, we use an unsupervised machine learning technique to categorize plasmaspheric hiss. In contrast to the previous studies, this technique allows us to identify power spectra that have "similar" shapes and study their spatial distribution without averaging together vastly different spectral shapes. We show that strong negative correlations exist between the hiss frequency and bandwidth. Key Points: Unsupervised machine learning is used to categorize hiss power spectra of the electric field from Van Allen ProbesFrom the pre‐noon sector toward the afternoon sector the hiss frequency decreases while the bandwidth increasesWe discuss possible source mechanisms that are consistent with the spatial distribution of the hiss waves [ABSTRACT FROM AUTHOR]

Energy forecasting plays a vital role in mitigating challenges in data rich smart grid (SG) systems involving various applications such as demand‐side management, load shedding, and optimum dispatch. Managing efficient forecasting while ensuring the least possible prediction error is one of the main challenges posed in the grid today, considering the uncertainty in SG data. This paper presents a comprehensive and application‐oriented review of state‐of‐the‐art forecasting methods for SG systems along with recent developments in probabilistic deep learning (PDL). Traditional point forecasting methods including statistical, machine learning (ML), and deep learning (DL) are extensively investigated in terms of their applicability to energy forecasting. In addition, the significance of hybrid and data pre‐processing techniques to support forecasting performance is also studied. A comparative case study using the Victorian electricity consumption in Australia and American electric power (AEP) datasets is conducted to analyze the performance of deterministic and probabilistic forecasting methods. The analysis demonstrates higher efficacy of DL methods with appropriate hyper‐parameter tuning when sample sizes are larger and involve nonlinear patterns. Furthermore, PDL methods are found to achieve at least 60% lower prediction errors in comparison to other benchmark DL methods. However, the execution time increases significantly for PDL methods due to large sample space and a tradeoff between computational performance and forecasting accuracy needs to be maintained. [ABSTRACT FROM AUTHOR]

In field reliability analyses, a data collection period is given to monitor the failure events from the field. Left‐truncation arises due to early failures occurring before the data collection period, and right‐censoring arises for late failures occurring beyond the monitoring period. Naïve analyses of left‐truncated and right‐censored data lead to biased estimation of the population lifetime of interest. A variety of models and methods have been developed to analyze the left‐truncated and right‐censored data for field reliability analyses. The goal of the paper is to review the existing models and methods for fitting left‐truncated and right‐censored data. Our review includes the existing statistical models, such as the exponential, Weibull, lognormal, gamma, Gompertz, Lomax, and spline models. We comprehensively review the statistical issues of maximum likelihood estimation, model selection, residual lifetime prediction, and Bayesian methods. Some of these methods are illustrated through the field reliability analysis of the electric power transformer dataset. [ABSTRACT FROM AUTHOR]

This paper exhibits a sensorless speed control method based on full‐order‐sliding‐mode observer applied to a fault‐tolerant permanent‐magnet‐synchronous motor (PMSM) drive system. So, this paper proposes a rapid method of fault switch detection in the power converters aiming to make sure of the continuity of service despite the fault presence of an opening phase. In fact, the full‐order‐sliding‐mode observer (FO‐SMO) observer is used to replace the mechanical sensor and a redundant inverter leg is equally employed to replace the faulty leg. The proposed new fast fault diagnosis method has the features of a simple algorithm, independent of the transient states and being simply integrated without any additional sensors. [ABSTRACT FROM AUTHOR]

As for the insufficient nature of the fossil fuel resources, the renewable energies as alternative fuels are imperative and highly heeded. To deliver the required electric power to the industrial and domestic consumers from DC renewable energy sources like fuel cell (FC), the power converter operates as an adjustable interface device. This paper suggests a new boost structure to provide the required voltage with wide range gain for FC power source. The proposed structure based on the boost converter and the quazi network, the so‐called SBQN, can effectively enhance the FC functionality against its high operational sensitivity to experience low current ripple and also propagate voltage and current with low stress across its semiconductors. Furthermore, the switching power losses have been decreased to make this structure more durable. A full operational analysis of the proposed SBQN and its advantages over the conventional and famous structures has been compared and explained. Furthermore, a prototype of the single‐phase converter has been constructed and tested in the laboratory. [ABSTRACT FROM AUTHOR]

The electric power propulsion is becoming the important development direction of ship propulsion technology recent years, as it is conducive to the realization of automation, intelligence, reduced noise, enhanced propulsion efficiency, high power density, flexible arrangement, and energy saving. The good fault‐tolerant capacity and robustness of the fault‐tolerant permanent magnet motor (FTPMM) make it a potentially highly effective and economical propulsion motor in the electric power propulsion ship than other alternatives. In this paper, the structure and mathematical model of FTPMM are analyzed and the improved sliding mode observer (SMO) is constructed according to the deviation between the observed currents and actual currents. Combined with model reference adaptive control (MRAC) method and the phase‐lock loop (PLL), the switch function is replaced by the continuous Sigmoid function to reduce the chattering and finally the rotor position estimated accuracy is improved. When the motor winding open‐circuit and short‐circuit fault occur, the current vector fault‐tolerant control strategy is introduced into the improved SMO algorithm, and the rotor position is estimated accurately under faulty conditions. Finally, the proposed improved SMO position estimation algorithm under healthy and faulty conditions is verified in Matlab/Simulink. The FTPMM position sensorless technology would play a critical role in the electric power propulsion ship, and may have a profound impact on the high‐performance advanced ships and green shipping industry as well. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Networks describe a wide range of systems in nature and society including examples the Internet, metabolic networks, electric power grids, supply chains, and the world trade Web among many others. The stability and reliability of a network are of prime importance to network designers. The domination number and its various, for example, bondage number, reinforcement number, etc. have been used network vulnerability parameters. Very recently, the average lower bondage number has been defined by Turacı in Reference [27]. In this paper, the average lower bondage number of the corona graphs and join graphs of given any two graphs G1 and G2 have been investigated, also exact formulas have been obtained. [ABSTRACT FROM AUTHOR]

Summary: The paper presents a new configuration of a grid‐connected converter centering on the needs of voltage‐sensitive nonlinear loads with source current compensation and photovoltaic (PV) power injection capability. The presented system consists of a six‐switch converter, which gives dual single‐phase output. The first output is connected in shunt near the source end to inject PV‐generated power along with the supply of load current harmonics and reactive power. The second output forms a series connection near the load end to protect the voltage‐sensitive nonlinear load from supply‐side voltage variations such as sags and harmonics. The system operation is validated through MATLAB simulation and real‐time simulation using Opal‐RT (OP4510) under different dynamic conditions such as variations in supply voltage, variation in solar irradiance, and load variation which is typically encountered in a modern distribution network. The performance of the proposed multifunctional converter is found to be satisfactory in all operating conditions by meeting the desired PV power injections along with the compensation of sensitive nonlinear load terminal voltage and source current harmonic issues within the standard allowable limit specified by IEEE. [ABSTRACT FROM AUTHOR]

This paper presents a control mechanism on high voltage direct current (HVDC) transmission line for frequency/voltage regulation, fault ride through (FRT) capability, and cyber‐attack/fault detection. The network under study consists of two areas with different frequencies that are connected through one 300 km HVDC line. The proposed control system regulates the frequency in both areas by managing power through HVDC line. The converters on both sides of HVDC line are controlled to handle faults on the DC and AC sections as well as improving fault ride through capability. The control strategies are implemented and operated depending on fault/cyber‐attack type and behaviour. In this respect, the control mechanism may change the firing angle of converters, switch their operating mode from rectifier to converter and vice‐versa or even block the converters. The proposed paradigm successfully distinguishes between the cyber‐attacks and faults. The simulations in MATLAB software validate that the proposed mechanism realizes all the objectives and the cyber‐attacks are completely identified and separated from the faults. [ABSTRACT FROM AUTHOR]

In this paper, a new model of electric power supply‐demand analysis based on a clustered unit commitment (CUC) model is proposed. This method enables to derive daily generation plans in multi‐area by minimizing daily generation cost. In the CUC model, the generation units are clustered for the purpose of saving calculation time of the optimization. The proposed model is formulated by Mixed Integer Linear Programming (MILP). The numerical experiment of annual supply‐demand analysis was done to evaluate the availability of the proposed model. As a result, the availability of proposed model was clarified in the view of calculation time and operational results, which are derived by the numerical experiment. [ABSTRACT FROM AUTHOR]

In recent times, regional renewable energy sources (RES) are increasingly integrated with the existing electric power grid by onboarding certain superior power quality features, thereby helping them in meeting massive electrical demand. This grid integration drastically reduces the use of fossil fuels, besides preventing environmental hazards as well. However, in grid‐connected systems, with RES such as photovoltaic (PV) systems and wind energy systems, many power quality issues (PQ) still crop up. In this paper, Gray Wolf Optimization (GWO), in conjunction with a static synchronous compensator (STATCOM) is suggested to address such challenges in the RES integrated grid‐connected PV systems. The intermittent nature of solar PV power under shading conditions can be harnessed by using the GWO approach. STATCOM is one of many specialized power electronic devices that effectively reduce power quality concerns such as voltage sag/swell and Total Harmonic Distortions. The fast‐acting PI controller is intended to drive a STATCOM by using some tuned parameters for maintaining the DC link voltage as constant. The best findings are attained after these results are compared with PI. The test system is modeled using the MATLAB/Simulink environment. [ABSTRACT FROM AUTHOR]

Converter interfaced distributed generations in a microgrid feed the modulated current of limited magnitude during fault conditions. The protection design and its operation are thus challenging due to limited fault current which is further reduced by Petersen coil grounding in medium‐voltage (MV) level. This paper aims to address this challenge by developing a current‐only directional relay algorithm for the protection of converter dominated MV microgrid with Petersen coil grounding. The relay's operating principle is based on the sign of the change in phase angle of the fault current with respect to the prefault which indicates the direction of fault. The negative and positive changes in current's phase angle determine the fault in forward and reverse direction, respectively. The tripping decision is derived by comparing the binary output of the relay at both ends of the line segment under protection. This requires a simple, flexible and low bandwidth communication channel. Both theoretical analyses and simulation studies have been performed on a typical distribution grid intended to be operated as microgrid. The proposed protection method is suitable for microgrid having the converters with and without reactive power support. Various operating conditions are evaluated, including bidirectional power flow, high resistance fault, different fault types, loading conditions and signals with noise. [ABSTRACT FROM AUTHOR]

For a few decades, electric power growth and demand have increased globally. To fulfil this demand, distribution generators (DGs) have been installed in the power system. To get numerous benefits such as comprising reduction of power losses, improvement of (voltage, current, rpm) transient stability, leads to economic benefits. DGs integration in the distribution power system (DPS) was reported as an optimal generator placement (OGP) problem to maximize these benefits. This paper performs wind turbine (WT) integration while considering the internal generator's (rpm) transient stability under fault conditions. A power loss index (PLI) method is implemented to select potential candidate buses for generator placement. A self‐sorting analytical approach (SSA) is also used to determine the optimal bus and WT size. The IEEE 14‐bus DPS is used as the OGP test system to demonstrate the proposed method's effectiveness in terms of power losses reduction, system transient stability, and economic benefits. The IEEE 14 Bus system was considered using MATLAB with a 3.2 GHz processor to perform the said approach. WT integration suggested in case‐2 results in a 65.80% power losses reduction, which leads to a 60.88% enhancement of economic benefits of the DPS. [ABSTRACT FROM AUTHOR]

This paper proposes an enhanced three‐layer predictive hierarchical power management framework for secure and economic operation of islanded microgrids. The tertiary control, guaranteeing the microgrid economic operation, is built upon the semi‐definite programming‐based AC optimal power flow model, which periodically sends power references to secondary control. To mitigate uncertainties arising from renewable generations and loads, a centralized linear model predictive control (MPC) controller is proposed and implemented for secondary control. The MPC controller can effectively regulate the microgrid system frequency by closely tracking reference signals from the tertiary controller with low computational complexity. Droop‐based primary controllers are implemented to coordinate with the secondary MPC controller to balance the system in real time. Both synchronous generators (SGs) and solar photovoltaics (PVs) are simulated in the microgrid power management framework. A unified linear input‐state estimator (ULISE) is proposed for SG state variable estimation and control anomaly detection due to compromised cyber‐physical system components, etc. Simulation results demonstrated that SG states can be accurately estimated, while inconsistency in control signals can be effectively detected for an enhanced MPC. Furthermore, comparing with conventional proportional‐integral (PI) control, the proposed hierarchical power management scheme exhibits superior frequency regulation capability whilst maintaining lower system operating costs. [ABSTRACT FROM AUTHOR]

The control scheme for an electric motor drive is generally implemented by involving proportional‐integral (PI) controllers in current and speed feedback control loops. A good design of PI controller parameters has always been a challenging task for control system design engineers. This paper describes the D‐decomposition method for the design of the parameters of involved DC‐link current and speed PI controllers in closed‐loop scheme of a pulse width‐modulated, current source inverter (CSI)‐fed squirrel‐cage induction motor drive. The PI controllers ensure the stable operation of CSI‐fed induction motor in natural unstable operating region of its torque‐slip characteristic. In order to achieve smoother speed tracking performance with minimum overshoot/undershoot, the damping ratio has been pre‐specified while designing the PI controller parameters using the D‐decomposition method. Simulation results have been presented to confirm the design and have been compared with the results already published. [ABSTRACT FROM AUTHOR]

UV radiation is considered indispensable from the hygienic, medical, aesthetic, and industrial perspectives. Among the various types of UV radiation, UV‐A (with a wavelength of 315–400 nm) has a significant influence because it adversely affects human skin, leading to damage such as blemishes, freckles, and wrinkles. Although various photosensors are developed for monitoring UV‐A radiation in real time, these devices have critical issues, such as inefficient fabrication processes, insufficient photoresponsivity, and incompatibility with long‐term wearable applications. Here, the authors report on a wearable UV‐detecting patch targeted for long‐term use in the medical and clinical fields. A wearable UV sensor is fabricated by integrating optimized InGaN/GaN microphotodetectors (µPDs) in a 3D porous patch. The optical and electrical properties of the device are intensively investigated under various types of optical radiation and input electrical power and show high photoresponsivity (2.82 A W−1) and excellent external quantum efficiency (897.63%). Long‐term real‐time UV radiation monitoring using the wearable µPDs is demonstrated; moreover, the by‐products can be efficiently removed from human skin surfaces. [ABSTRACT FROM AUTHOR]

This study assessed the quality and challenges of health data before and after the implementation of the Hospital Information System (HIS) for the fistula program at the Comprehensive Community‐based Rehabilitation Hospital in Tanzania. This was a mixed methods study. Data were collected at baseline and end‐line (before and after the implementation of the HIS) study using quantitative Data Quality Assessment (DQA) checklists and individual interviews. At the baseline, the DQA checklists were assessed using files registered from 2017 to May 2019. At the end‐line, the DQA checklists used data for a patient registered at the established HIS from June 2019 to December 2020. Interviews with clinical and non‐clinical staff were conducted at both baseline and end‐line studies. The study found that data quality improved after the implementation of the HIS. At baseline, data completeness declined from 85% in 2017 to 44.9% in 2019 while accuracy declined from 44% in 2017 to 31% in 2019. At the end‐line, data completeness and accuracy were >80% and 100% annually respectively. Data preciseness increased from 0% at baseline to 100% at the end‐line. Both data completeness and accuracy had inconsistent tend over months, although preciseness could not be evaluated at baseline as no breakdown of indicators was reported. The major challenges related to data quality included language barrier, incompleteness of data, incorrect data entry, use of both manual and electronic systems, as well as unreliable electricity and network. In general, the HIS had improved rates of data quality in terms of completeness, accuracy, and preciseness of data as compared to the manual system. Policy‐makers and hospital administrators should ensure that the HIS are integrated into national hospital information systems, build staff capacity, ensure reliable sources of electrical power, and regular training on data collection. [ABSTRACT FROM AUTHOR]

Improving network power quality through harmonic reduction requires recognition of Harmonic Sources (HSs) to drive them to compensate their harmonics. This paper proposes a new method for equitable distribution of the Harmonic Compensation Cost of the network among the HSs based on the Harmonic Contribution Matrix. Each element of the Harmonic Contribution Matrix is the harmonic contribution of a specific source to the harmonic voltage of a specific bus. The output of the proposed method is a penalty curve for each HS over time. The amount of the fine estimated for each individual HS per hour is a function of not only the contribution of that HS to the harmonic voltage of different buses, but also the contribution of the Harmonic Compensation Cost from the perspective of each bus, nominal voltage of each bus, and the sensitivity of each bus to the harmonic voltage. The proposed algorithm is evaluated on the IEEE 14‐bus network and Esfahan regional electrical power network in Iran. The simulation results demonstrate the capability of the proposed method to allocate the hourly penalty curve to the HSs. [ABSTRACT FROM AUTHOR]

This paper proposes a robust investment and operation model to attend the power and heat needs of a microgrid (MG) connected to the distribution system. The optimization algorithm decides on the best investment and operation of combined heat and power (CHP), boilers, PV power generation and battery energy storage systems (BESS). For the BESS, the algorithm estimates the optimal energy storage capacity (MWh) as well as the maximum hourly delivery capacity (MW). The non‐linear and non‐concave heat rate chart is recast by a mix‐integer linear model to have a tractable and precise model. The model considers the uncertain in some parameters using probability density function (pdf) to portrait its behavior. Thus, the problem has been modeled using stochastic programming approach, and its objective function is the expected value of the annual operational cost. The model is tested using a real case where two adjacent consumers share the power and heat facilities to minimize the overall up to 17% depending on the gas price scenario. The results demonstrate the benefits of employing different technologies and the synergies of all technologies operating together. [ABSTRACT FROM AUTHOR]

This paper elaborates on optimal scheduling of coordinated power and natural gas (NG) networks in the presence of interconnected energy hubs considering reconfiguration as a flexibility source. With regard to the energy hub system consisting of several generation units, storage and conversion technologies, as well as natural gas‐fired units, the high interdependency between gas and electricity carriers should be captured. The hourly reconfiguration capability is developed for the first time in a multi‐energy system to enhance the optimal power dispatch and gas consumption pattern. The realistic interdependency of electrical and NG grids is investigated by employing the steady‐state Weymouth equation and AC‐power flow model for power and gas networks, respectively. Furthermore, to handle the risk associated with strong uncertainty of wind power, load, and real‐time power price, the conditional value at risk approach is employed. The proposed model is implemented on the integrated test system and simulation results are presented for different cases. The impact of the risk aversion level on operating cost and optimal scheduling of controllable units is examined. Numerical results demonstrate that reconfigurable capability reduces the operational cost up to 7.82%. [ABSTRACT FROM AUTHOR]

The threat of Geomagnetically Induced Currents (GICs) driven by severe Space Weather looms over technological systems such as power grids. Assessing their vulnerability is thus vital to avoid damages or even disruption of the electrical power supply. This endeavor, however, entails an interdisciplinary approach, ranging from the characterization of the geoelectrical structure of the Earth beneath and around the area of interest, or the modeling of the power network from its parameters and topology, and including the validation of the modeling process by means of (direct or indirect) GIC flow measurements. In this paper, we summarize our current achievements focused on mainland Spain, concentrating on the improvements reached after going from a homogeneous Earth's resistivity to an alternative 3D electrical resistivity distribution approach to geoelectric field computation, which is still in progress because new empirical impedance tensors are needed, mainly at sites in the west of the Iberian Peninsula. The second major achievement has come from the addition of the 220 kV level to the network model. The overall improvement has been validated against real GIC data in one area of the country. The new vulnerability maps show that in some nodes the predicted GIC has been substantially reduced by the sum of both effects. The assessment has been carried out down to the level of the individual windings of each transformer, and examples of the estimated GIC flow are given for substations with numerous power transmission lines converging to them at diverse orientations. Plain Language Summary: The Sun can lead to violent phenomena, expelling huge amounts of energy and matter traveling within the solar wind. When such bursts impact the Earth they can trigger phenomena known as Space Weather events. Current systems of our magnetosphere and ionosphere undergo dramatic variations, giving rise to magnetic fields that reach the surface, where numerous technological systems are deployed. The conductivity of the subsoil determines the geoelectric fields that are mapped along terrestrial conductors such as power networks, railways, or oil and gas pipelines. The geomagnetically induced currents (GICs) thus generated are potentially dangerous and can cause multiple adverse socio‐economic impacts. We develop here an assessment of the vulnerability of the Spanish power network to GICs, thus providing useful products that enable the operators to mitigate their effects. Geomagnetic field measurements are convolved with a newly developed earth resistivity model to provide the geoelectric field. This quantity is then input into an updated and extended model of the power network to have a quasi‐real time estimate of the expected impact and produce new and more accurate vulnerability maps. We have also established points of measure under power lines, aimed at validating both the power grid and the ground resistivity models. Key Points: Improvements are achieved by using a 3D inversion of magnetotelluric (MT) data to derive the electric field and adding the 220 kV level to the network modelMore accurate geomagnetically induced current (GIC) estimates for all power transmission lines, nodes and transformers are providedThe system experiences a reduction in GICs flowing to ground, but at the transformer winding level they exhibit, in general, an augmentation [ABSTRACT FROM AUTHOR]

In this article, a method is proposed to increase the accuracy of reactive power‐sharing for parallel‐connected inverters in Microgrid, this method is done by automatically adjusting the values of the virtual impedance to adjusting the output voltage of the inverters. The virtual impedances are automatically adjusted to compensate for the difference in the output voltage of the inverters due to the influence of the line impedances. The output voltage of the inverters will be adaptively adjusted according to the change of the load, this method greatly improves the accuracy in the reactive power sharing The correct power sharing for the inverters will ensure the stability of voltage and frequency in the Microgrid. The control method is simple and does not need to know the line impedance parameter. The feasibility and effectiveness of the proposed strategy are proven by simulation and experimental results. The proposed method in this paper can remove the disadvantages of the conventional virtual impedance method. The focus of this article is to improve the accuracy of power‐sharing so only nonlinear loads are considered. [ABSTRACT FROM AUTHOR]

The aim of the security and stability control system (SSCS) is to maintain active power balance and frequency stability. For large SSCS, it is difficult to find the state space and the transition rates of the paths. The flat design yields more complex topology. Considering the random outages, the ultra‐high‐voltage dc (UHVDC) has more capacity levels and states. The existing evaluation cannot quantify the power balance capability of the SSCS. This paper newly quantifies active power balance capability of the multi‐level SSCS with partial or complete outage of the UHVDC. An incidence matrix is proposed to describe the topology of the SSCS. A recursive solution to calculate the transition rates is proposed. The equivalent downward transition rate is newly defined. The increasable generation and the transition rates of the UHVDC at any initial state are newly included. The numerical analysis shows that the incidence matrix and recursive algorithm reduces the calculation effort for the practical SSCS with multi‐level, redundancy component, and flat design. The active power balance capability of the SSCS is decided by the increasable power, the reduced generation and the downward transition rate. [ABSTRACT FROM AUTHOR]

The demand for electric power has consistently been on the rise, owing to urbanisation and technological improvements. On the generation side, renewable sources have been favoured over their polluting, exhaustible, non‐renewable counterparts. These changes in the power system have necessitated a system for maintaining the supply‐demand balance, to maintain system stability. A complex power system is also more prone to blackouts and grid failure. Islanding helps in provision of supply to consumers in a microgrid, reducing the possibility of a blackout. Depending on the power demand and generation, loads need to be shed or restored to mitigate power imbalances. A wide area distribution management system (WADMS) is proposed to dynamically shed and restore loads in the islanded mode, with the aid of micro phasor measurement units (µPMUs). A priority and consumer‐based load shedding and restoration (PCLS) algorithm is proposed in the WADMS that preferentially sheds or restores loads based on their assigned load priority indices and number of consumers. The algorithm has been tested on a modified IEEE 13 bus system, incorporated with a solar photovoltaic (PV) system, diesel generators (DGs) and an energy storage system (ESS) in MATLAB Simulink. [ABSTRACT FROM AUTHOR]

The power frequency electric field is the most important electromagnetic environmental factor in alternating current power transmission projects. The humidity has a negative influence on available electric field measuring devices, which may lead to discrepancies of up to seven times the actual value at a relative humidity exceeding 80%. The changes in the support and probe shell impedance may be the reason for the error. The optimization measures include modifying the communication mode, designing a suitable structure and circuit for the probe, and using composite insulating material with strong hydrophobicity for the support. A three‐axis omnidirectional electric field measuring device was developed based on wireless communication and composite support. The variation of the measured electric field strength value is less than 1% at relative humidities ranging from 45% to 90% in the laboratory, and the measured results obtained in high humidity at the high‐voltage test site and under the transmission line demonstrated high accuracy. The research demonstrates that the composite support can be used to improve the performance of conventional devices. The proposed device can better meet the needs for accurate measurement of electric field strength in a high‐humidity environment and overcome the technical problems raised by the IEC standard. [ABSTRACT FROM AUTHOR]

Considering that nearly 39% of the total CO2 emission released into the atmosphere today are thought to be due to the energy consumed by buildings, the importance of taking measures through buildings to combat global warming is evident. Therefore, the concept of nearly zero‐energy buildings (NZEB) is come to the forefront. Building integrated photovoltaic thermal (BIPV/T) systems are used to enable buildings to generate their own energy. However, buildings have limited facade and roof areas required for BIPV/T systems. Therefore, in this study, various configurations of bifacial (double‐sided) and monofacial (single‐sided) panels were compared to investigate ways to enhance the efficiency of BIPV/T systems. Different air flow velocities and varying air gap distances were tested for both panel types. By placing a reflective surface on the wall behind the bifacial panel, the electrical efficiency of the bifacial panel was increased and proven through PVsyst analysis. Both panels provided maximum heat efficiency at the shortest air gap distance under high air flow conditions. In addition, it was shown in both the experimental setup and Comsol CFD analysis that it provides significant benefit in the thermal energy load of the building when heating the interior environment in winter. In terms of electrical power production surplus, the bifacial panel outperformed the monofacial panel in all configurations, with a minimum advantage of 8.33% and a maximum of 12.73%. Additionally, the maximum electrical efficiency was obtained from the bifacial panel in configurations with the longest air gap distance. Using the bifacial panel in the BIPV/T system with the shortest air gap distance during the heating season and the longest air gap distance during other seasons can provide the highest efficiency for the building throughout the year. [ABSTRACT FROM AUTHOR]