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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]

Earlier work using the time dependent Poynting theorem has shown that the complete description of power in a multimodal radiation field requires the use of three numbers; two are sufficient only with a single modal field. Where three numbers are required it is not possible to correctly represent power as a complex number. In the common notation the third number is a suppressed phase angle; when multiple power fields are combined to form a single one it is essential to account for the suppressed phase angles. The differences in power calculations using the time and frequency domain power theorems are manifest in determination of the energy flow that remains local to the source, oscillating between the near field and source, which does not form part of the far field power. In this paper we numerically model, using commonly accepted frequency and time domain techniques, the simplest antenna design that clearly illustrates the differences between time and frequency domain representations of reactive power. We calculate and contrast the instantaneous and the steady-state far field and local powers emitted from two identical, perpendicularly oriented electrically small TM dipoles as a function of relative phase between the two dipoles. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

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]

A greedy randomized adaptive search procedure (GRASP) is a metaheuristic for combinatorial optimization. It is a multi-start or iterative process, in which each GRASP iteration consists of two phases, a construction phase, in which a feasible solution is produced, and a local search phase, in which a local optimum in the neighborhood of the constructed solution is sought. Since 1989, numerous papers on the basic aspects of GRASP, as well as enhancements to the basic metaheuristic, have appeared in the literature. GRASP has been applied to a wide range of combinatorial optimization problems, ranging from scheduling and routing to drawing and turbine balancing. This is the second of two papers with an annotated bibliography of the GRASP literature from 1989 to 2008. In the companion paper, algorithmic aspects of GRASP are surveyed. In this paper, we cover the literature where GRASP is applied to scheduling, routing, logic, partitioning, location, graph theory, assignment, manufacturing, transportation, telecommunications, biology and related fields, automatic drawing, power systems, and VLSI design. [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]

The paper represents a comprehensive review of the wind farm layout and reliability assessment of the wind farm integrated electrical power system. The authors have done a review on the proliferation of renewable energy which raises the uncertainties in the electrical power system. The uncertainties including wind speed and wake effect are important to deal with when an isolated microgrid is considered. The scenario becomes vigilant when the wind farms are integrated with the main grid. Due to uncertainties, the study of reliability evaluation of a wind integrated power system would become significant to analyse the electrical power system behaviour effectively. So, the paper discusses the layout optimisation methods of wind turbines considering the uncertainty parameters, mainly the wake effect. In this regard, the different wake models and optimisation methods based on a single‐objective and multi‐objective functions are reviewed in detail with the proper comparisons. The paper serves as a better illustration of the competency of these optimisation methods on the optimal wind turbine location on a wind farm. Furthermore, the paper extends the view on the reliability and cost assessment, and reliability improvement techniques of the wind integrated power system. This article provides comprehensive information, yields an attractive and subsequent tool for research requirements for the researchers to design the wind farm layout, and assessed the reliability of a wind integrated power system. [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]

This paper proposes an optimal coil layout of wireless power transfer (WPT) systems for underwater vehicles (UVs). The power supply station adopts a multicoil arrangement with a double layer, and the UV also uses two receiving coils. The proposed WPT system for UVs has a reasonable advantage, where it does not request to adjust the relative position of coils. This paper experimentally discusses an optimal coil layout based on measurement results of a coupling coefficient. As a result, the proposed coil arrangement with the geometry rule realizes a certain power transfer under any positions and directions of UVs. [ABSTRACT FROM AUTHOR]

Brayton–Moser's mixed potential theory has been used to analyse the large disturbance stability of DC microgrid with constant power load (CPL), such as current-mode controlled BUCK/BOOST converter with CPL or DC system with multi-stage LC filters. However, the stability analysis of other topology of DC–DC converter or multiple converters worked under droop control is rarely involved. Based on this issue, this paper first establishes the mixed potential model of a single bidirectional BUCK/BOOST converter with CPL. Then, the paper gives the method for establishing the mixed potential model of a droop-controlled DC microgrid with multiple bidirectional BUCK/BOOST converters and CPL. Afterwards, the stability criterion of the analytic form of the system under large disturbance is obtained, which shows that the parameters such as system parameters, control parameters, droop coefficients, and CPL power value have the effects on the system's large signal stability. This paper gives and discusses the relationship between system parameters and stability. Thus, instead of calculating and simulating repeatedly, the stability criterion can judge and ensure the stability of the system under large disturbance in the design process. Simulation results demonstrate the correctness of the simple and easily implemented stability criterion. [ABSTRACT FROM AUTHOR]

When a DC line fault happens, the converter will be blocked instantly. This leads to an interruption of power transmission and influences the stability of DC and AC systems. To avoid the blocking of converters, this paper presents a novel protection scheme for VSC-HVDC system, which consists fault isolation and auto-reclosing of DC circuit breaker (DCCB). First, this paper coordinates the protective actions of converters and DCCB. The DC line fault is cut immediately by DCCB while the blocking signal of converter is isolated during the fault. Second, since the faults of long overhead transmission DC lines are mostly transient, an auto-reclosing strategy is developed. The emphasise of this part, which includes fault discrimination and time sequences, between DCCB and converter is elaborated, and the value of reclosing delay is derived by analysing the charging and discharging characteristics of capacitor paralleled with converter. Finally, the protection scheme is evaluated by overcurrent, overvoltage, and recovery time of DC system, and simulation results of a point-to-point VSC-HVDC transmission system proves its validity. [ABSTRACT FROM AUTHOR]

This paper designs a new AC & DC hybrid power supply system for data centres, which includes photostatic power generation, wind power generation, solar thermal power generation, storage power systems, and different types of loads. According to the above-mentioned, the paper first presents the reliability evaluation indicators and analysis methods applicable to the new AC & DC hybrid power supply system for data centres, which are for solving the problem of the reliability evaluation under uncertain parameters and load parameters of the new data centre power supply system. The paper describes the new power supply system reliability indicators and evaluation methods in detail. The problem of the power supply reliability in the new AC & DC hybrid power supply system in the data centre is analysed in a targeted manner by adopting actual examples, then it is verified that the power supply reliability of the new AC & DC hybrid power supply system can perfectly meet the qualification of the A-class data centre power supply. The reliability of assessment index and analysis methods presented here will be two simple and superior analysing tools. [ABSTRACT FROM AUTHOR]

Voltage source converter‐high‐voltage direct current (VSC‐HVDC) is an effective way to ensure the reliable supply of offshore island power. However, it is easily liable to direct current (DC) oscillation or even instability due to the interaction between the rectifier and inverter stations. In order to solve this problem, this paper analyzes the stability of the VSC‐HVDC system caused by DC capacitors based on VSC impedance modeling and impedance stability criterion. Besides, an adaptive virtual impedance control strategy to suppress the DC oscillation is proposed. The impedance models of the VSC in the rectifier and inverter stations are constructed and verified. Then, the influence of the DC capacitors on the system stability is analyzed based on impedance stability criteria. The analysis shows that the decrease of DC capacitors will cause DC oscillation, and the DC virtual impedance is used to damping the oscillation. Finally, this paper presents a simple but effective adaptive fuzzy segmented virtual impedance control strategy to suppress the oscillation. Electromagnetic transient simulation and hardware‐in‐the‐loop (HIL) test results show that the proposed adaptive virtual impedance is more effective and has better robustness than the conventional virtual impedance. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Three-level voltage space phasor can be obtained using a dual two-level voltage source inverter (VSI). Two zero sequence voltage elimination pulse width modulation (PWM) switching variants are proposed in this paper for complete elimination of zero sequence voltage (ZSV) in the dual-VSI scheme. Both the PWM variants are designed in such a way that only one inverter is switched at any instant of time; to ensure that switching power losses in the dual-VSI is limited to one inverter only at any instant of time. Analytical expressions for the dwell times of the dual-VSI are developed and presented that successfully forces the ZSV in the dual-VSI to zero; at all instants of time. As a result, both the PWMs facilitate the dual-VSI to be driven from a single DC power source only. The implementation of the proposed PWM algorithms is greatly simplified and involves just the use of instantaneous magnitudes of the reference space vector. The implementation of PWMs totally avoids the time consuming task of sector identification and do not use look up tables. The PWMs proposed in this paper are first analysed, simulated using MATLAB/SIMULINK and then verified experimentally to validate the proposed PWMs. [ABSTRACT FROM AUTHOR]

This paper presents an ergonomic design of the display system in control rooms of four complex systems in Serbia, railway, mining, electric power, and soybean flakes production. Research of display panels analyses the visual information coding, characters' visual angles, and existing standards and recommendation in the period when this research took place. Operators' visual angles, the distance between the operator's eyes and display panels, the size of visual signs, comparative analysis of display panel and video display units used in the control room are given. The main goal of this paper is to apply the result obtained in designing a new control room in Serbia since the adequate design of display systems in control rooms has a significant impact on the efficiency and functionality of the operator's work in control centers. [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]

China is actively taking measures to guide the household energy‐saving consumption pattern because the total household indirect energy consumption and CO2 emissions have rapidly multiplied from 2002 to 2017 with an annual growth rate of 5.95%, and 5.56%, respectively. This paper calculates indirect energy consumption and CO2 emissions by four energy sources (raw coal, crude oil, natural gas, and electricity), analyzes the energy structure, and conducts a structural decomposition analysis in urban and rural areas in China from 2002 to 2017. The results reveal that the indirect energy consumption and CO2 emissions of urban households was 3.84 and 3.80 times, respectively, that of rural households in 2017 with most contributions from the 'Agriculture, Forestry, Animal Husbandry, and Fishery', 'Foods and Tobacco', and 'OTHERS' sectors. The energy consumption structure has changed. The percentage of coal consumption falls from 66.87% to 57.62%. Electricity consumption, ranked second, increased substantially from 10.77% to 22.90%. The key sectors of the energy mix have been found to help energy conservation. The high indirect energy consumption sectors with higher indirect energy intensity are the key sectors, especially the 'Processing of Petroleum, Coking and Processing of Nuclear Fuel' and 'Production and Supply of Electric Power and Heat Power'. The consumption structure effect is more obvious in urban areas than in rural areas. In the process of urbanization, its effect has little impact on urban indirect energy consumption. It implies that the focus is on optimizing consumption structure rather than reducing consumption scale. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: This paper concludes that the deterioration of the mechanical quality factor Qm when operated under high power, can be recovered by externally applying positive DC bias field. Material constants for piezoelectric ceramics are generally characterized under low‐power conditions. However, high‐power properties deviate significantly from the ones measured under low‐power conditions (Qm degrades by a factor of ~2). DC Bias field helps to recover the properties of the ceramic under high‐power conditions. The DC bias field of 200 V/mm exhibits an almost equivalent “opposite” change rate to the vibration velocity of 0.1 m/s. It is also notable that the piezoelectric loss tan θ’ can be decreased most effectively under positive DC bias field (1.9% per 100 V/mm for the hard PZT and 3.1% per 100 V/mm for the soft PZT), in comparison with the elastic or dielectric losses. This report presents a comprehensive analysis on the low‐ and high‐power piezoelectric properties of hard and soft Lead Zirconate Titanates (PZT's) under externally applied DC bias field in the k31 resonance mode (transverse extensional). [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]

In the future, renewable energy (RE) generation systems will be constructed and interconnected to the power system by nonutility entities such as generation companies and residential customers. Therefore, generation expansion planning (GEP) should consider the effects of RE generation. The purpose of this paper is to discuss the best GEP from the economic, supply reliability, and environmental aspects considering the penetration of RE generation. For this purpose, this paper proposes a model of a utility's GEP process considering RE generation. The proposed method is based on stochastic dynamic programming (SDP) in which long-term uncertainties are modeled by geometric Brownian motion (GBM) and the binomial lattice process. The variation of RE generation output due to the weather conditions (short-term uncertainty) is also considered in the proposed method by means of the net load curve. [ABSTRACT FROM AUTHOR]

With the increase in power rating of electric vehicle chargers, concerns regarding their integration to the grid have likewise grown. This paper investigates a novel technique for start-up of high-power fast electric vehicle (EV) charger using a solid-state inrush current limiter (SSICL). The circuit consists of three similar sets of bidirectional switch and limiting resistor that utilizes a control strategy based on a simple Kalman filter (KF) to suppress the converter start-up current and transient overvoltages. In fact, the built-up profile of the inrush current is dictated in accordance with the estimated current by the slow dynamic KF. Compared to alternatives, such as start-up resistors, the presented SSICL achieves faster start-up with comparable peak current, tends to provide lower distortion, and provides a good balance between speed and efficiency. Simulation and experimental results confirm that the proposed method can considerably suppress inrush currents, while improving the total harmonic distortion. Comparing the behaviour of the SSICL to other relevant techniques underlines the advantages of the proposed solution. Furthermore, although the focus of this paper is start-up of the fast EV chargers, the proposed circuit can act as an inrush-current limiter in most AC to DC converter structures. [ABSTRACT FROM AUTHOR]

The quality of electric power caused by frequency fluctuation and voltage rise will be degraded because of the lightning surge and the mass introduction of distributed power. Thus, it is necessary to improve the performance of gas circuit breaker in order to maintain the stable supply of electric power. It has been reported that the arc conductance is calculated as the index of the current interruption in numerical analysis. However, few report have the measured value in the current interruption. This is because that the current interruption is the steep phenomenon of micro seconds range. Thus, it is necessary to establish the time‐high precision and noncontact measurement method. In this paper, the arc temperature is measured near current zero using the microsecond spectroscopic measurement. As a result, the microsecond spectroscopic measurement which combines the conventional spectroscope and the high speed video camera is 200 times faster than the measurement of conventional spectroscope. For this reason, the microsecond spectroscopic measurement is possible with the high speed video camera. Therefore, it is possible to measure the arc temperature with decreasing the current using the microsecond spectroscope. [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]

The purpose of the paper is to analyse the economic and political factors that have shaped West European fuel-use in power generation since the 1960s. The historical analysis concludes that political and institutional constraints have had a huge impact on fuel choice, especially on the construction of new plants. The influence of politics has, however, changed over time -- away from direct intervention towards regulation of decentralised markets. Further, the prospects for reactivating large-scale projects have become limited, and, as a result, the refurbishing and increased utilisation of existing plants, as well as conversions of plants to new fuels, soared in the 1980s and the early 1990s. Uncertainty about future fuel prices, few technical improvements in new plants, siting problems and stringent environmental regulations for new plants explain this development. Finally, the short-run flexibility of the West European power sector has improved since the 1970s, something which has important implications for the electricity sectors and fuel markets. [ABSTRACT FROM AUTHOR]

SUMMARY This paper proposes a new estimation method to determine arbitrary circuit parameters for the harmonic analysis of a distribution network. Harmonic analysis is important in maintaining electric power quality. An interesting phenomenon, a temporary cut-down of the harmonic voltage level at dawn, even if demand is slightly increasing at this time, is often observed in actual power systems. This paper proposes to utilize observations of this phenomenon to estimate circuit parameters. In addition, it is claimed that a detailed equivalent circuit is preferable to a conventional simplified equivalent circuit for explaining the phenomenon. This paper also discusses the usefulness of the Harmonic Characteristics Curve, which is proposed in this paper as a new concept, at the secondary winding of the distribution transformer, and the correlation of PQ, the monitored values of the active and reactive power at the secondary winding of distribution transformer. This correlation should determine the equivalent fundamental frequency admittance of the shunt capacitors installed for distribution lines. © 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 187(1): 16-23, 2014; Published online in Wiley Online Library (). DOI 10.1002/eej.22451 [ABSTRACT FROM AUTHOR]