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This paper focuses on two models used for the determination of power loss components in steel samples under dynamic magnetizing conditions. The considered models differ in their approach as far as the possibility of distinguishing bulk and localized eddy currents is concerned. Two samples of non-oriented electrical steel differing in silicon weight contents are the subject of experiments. A comparison of the obtained results, as well as their discussion, is given in the paper. [ABSTRACT FROM AUTHOR]

Power loss, voltage deviation and reliability are the issues that are widely encountered in the power system operation of developing countries. The Eastern region of Ethiopian Electric Power (EEP) is characterized by long transmission lines with no power generation units and large loads. Power loss and voltage profile deviations are experienced repeatedly in this region. The aim of this study is to present an extensive analysis of the role of Hybrid Renewable Energy Sources (HRES) used as Distributed Generation (DG) for power loss minimization, voltage profile and reliability improvement in EEP. The research work initially proves the superior performance of Manta Ray Foraging Optimization (MRFO) for the sizing and placement of DG. Optimal sizing and location of DG are then performed for the case study system using MRFO. The results indicate considerable power loss reduction and improvement in the voltage profile of the network. The reliability of the system is also improved by having an alternative energy source from RES. Wind and solar are considered as part of DG, the combination of which is then optimized through MRFO in the next part of the research. An economic feasibility analysis of the proposed result is also presented for this real-world problem. MATPOWER is used for executing the load flow whereas MATLAB programming is used for implementing MRFO. The result shows that the utility got economic benefits due to the introduction of DG to the network. [ABSTRACT FROM AUTHOR]

In order to solve problems such as a slow switching speed, a high switching power, a loss of pure IGBT modulators, and the weak withstanding load short-circuit ability of pure SiC MOSFET modulators used for vacuum loads, this paper proposes a new scheme for high-voltage pulse modulators based on SiC MOSFET/IGBT hybrid connecting circuits. It has a low power loss like the pure SiC MOSFET modulator and a strong withstanding load short-circuit ability like the pure IGBT modulator. Firstly, the principle circuit of the hybrid connecting modulator are discussed and chosen. And the basic working processes of the hybrid parallel-series modulator is described in detail. Secondly, three key points in this new scheme are analyzed and designed as follows: the static and dynamic voltage sharing; the actualizing of the ZVS process for IGBTs; the improvement of short-circuit protection for SiC MOSFETs. A modulator consisting of 16-stage 1200 V-SiC MOSFETs and 1200 V-IGBTs in hybrid parallel-series states is tested. Based on the sample circuit, the working data, such as high-voltage pulse waveforms of 10 kV/2 KHz/10 μs, static and dynamic voltage sharing, the driving control sequence, the U/I sequence of the IGBT, the short-circuit protection waveform, and the calculation, are obtained and discussed. [ABSTRACT FROM AUTHOR]

In this paper, we propose a single photonic crystal structure to implement NOT/XOR/OR optical logic gates using interference phenomenon. The gates are designed as T-shaped waveguides. The filter rods used in the design enhance the contrast ratio by up to 82.25 dB compared with the existing designs reported in the literature so far, and provides a maximum bit rate of 1.567Tbps with a response time of 0.63 ps. The proposed design exhibits minimum power loss, and performance parameters are enhanced compared to existing reported works. Photonic logic gates emerged as a potential substitute for their traditional electronic counterparts due to quick speed, low power consumption, and compatibility with current optical communication networks. The size of the proposed device is 144 μm2, can be used for future optical computing and communications. [ABSTRACT FROM AUTHOR]

Reactive power compensation (RPC) is a big problem during power system operation. Parenthetically, capacitor allocation and sizing may be the only convenient solution for RPC of power systems. The loss sensitivity factor (LSF) is applied here for finding the optimum capacitor position. This paper presents quasi-oppositional fast convergence evolutionary programming (QOFCEP), fast convergence evolutionary programming (FCEP), and evolutionary programming (EP) for the optimum location and sizing of shunt capacitors in the isolated microgrid (MG) for minimizing total real power loss throughout the day with and without the demand response program (DRP). The 33-node, 69-node, and 118- node isolated MGs have been studied to authenticate the efficacy of the suggested approach. Each MG includes small hydro power plants (SHPPs), solar PV plants (SPVPs), wind turbine generators (WTGs), diesel generators (DGs), and plug-in electric vehicles (PEVs). [ABSTRACT FROM AUTHOR]

As the electricity market expands with increasing demand, power systems are under more pressure to operate within secure limits. One way to ensure this is through load flow studies, which analyze the steady-state conditions of a power system under various load and generator scenarios. However, the complexity of power systems and the growing demand for electricity make it difficult to accurately predict and analyze power flow. The use of simulation software like electrical transient and analysis program (ETAP) can improve the accuracy and efficiency of load flow studies, but it still poses challenges such as complexity and lack of standardization in use. This paper focuses on voltage stability, voltage regulation, and the impact of capacitor banks on buses through load flow studies. Real data from four hydropower plants is used to analyze voltage drop, voltage regulation and power losses at each bus. The findings highlight the effectiveness of capacitor banks in improving voltage profiles and reducing power losses, thus proposing an optimized system design. These enhancements facilitate better planning, operation, and expansion of power systems, ensuring more reliable and efficient electricity supply. [ABSTRACT FROM AUTHOR]

The operation of modern power systems requires a sophisticated technological infrastructure to effectively manage and evaluate their parameters and performance. This infrastructure includes the generation, transmission and distribution power system components. This paper provides an overview of the loss evaluation to a part of Kosovo’s power system, substation with wind and photovoltaic (PV) energy sources integrated (SS Mramori, SS Kitka, and SS Kamenica) and the analysis of the loss assessment methods. One the assessment method in the research encompass simulated loss scenarios and their corresponding values in network components, employing the simulation based on the respective software tools. In current trends, power systems are visualized through the Supervisory Control and Data Acquisition (SCADA) platform. However, in Kosovo, although losses are integral to the SCADA system, they are represented as a overall value in the online mode, not encompassed depict losses per-components in real-time. This limitation hinders effective online power system optimization regarding the losses. As consequence, the purpose of this study is proposal a logical method developed through neural networks. The methodology incorporates various parameters, including as inputs variables; voltages, currents, active and reactive powers, and their computed values for extracting losses (X(x1, x2, ..., xn )). These parameters undergo systematic processing through hidden layers (Y(x1, x2, ..., xn )), leading to the classification of components within the power system. Finally, at the output stage (A(x1, x2, ..., xn )), an assessment is conducted based on the level of losses observed in the components of the power system. This implementation method promises significant benefits for transmission systems, impacting not only reducing losses, power quality but also yielding economic advantages. [ABSTRACT FROM AUTHOR]

Grid‐connected inverters with an inductor–capacitor–inductor (LCL) filter usually require the implementation of damping in the filter to suppress the resonance associated with the filter and hence ensure internal stability. The value for the damping resistor is commonly chosen as one‐third of the capacitive reactance at the resonance frequency of the LCL filter. However, this commonly‐used principle does not take into account the external stability of the inverter, i.e. the potential for an interaction between the inverter output impedance and the grid impedance. This work discusses a new design for the damping resistor to assure the external stability of the voltage source inverter as well as its internal stability. The analysis shows that the proposed design can ensure the external stability of the voltage source inverter with different grid impedances as well as robustness against the variations of the filter parameters while maintaining low power losses and an acceptable attenuation rate for high‐frequency harmonics. To validate the theoretical analysis, a 1 kW, 110 V laboratory prototype is implemented. The obtained results confirm the applicability of the proposed design approach. The value for the damping resistor of the inductor–capacitor–inductor (LCL) filter resonance is commonly chosen as one‐third of the capacitive reactance at the resonance frequency of the LCL filter. However, this commonly‐used principle does not take into account the external stability of the inverter, i.e. the potential for an interaction between the inverter output impedance and the grid impedance. This work discusses a new design for the damping resistor to assure the external stability of the voltage source inverter as well as its internal stability. [ABSTRACT FROM AUTHOR]

The world depends heavily on electrical energy for accessing technologies. For the generation of electricity, technology can utilize renewable energy sources like solar energy and wind energy. Solar photovoltaic (PV) systems occupy space among consumers due to their feasibility, flexibility, cost, and simple implementation procedures. The solar PV system experiences many factors causing power loss like partial shading, hotspots, and diode failure. In this work, a new static PV array configuration, named Renzoku puzzle patternbased array configuration, is proposed. This proposed configuration technique was designed to overcome the drawbacks of the previously proposed array configurations in terms of power generation, fewer mismatch losses, a high shade-dispersion rate, and consistent performance under any level of partial shading. The proposed array configuration has been validated using both simulation and hardware. The simulation is carried out in a 9 x 9 PV array in MATLAB/Simulink®. The performance analysis, results, and corresponding characteristic curves are presented in this manuscript. [ABSTRACT FROM AUTHOR]

In recent times, adverse environmental changes and the gradual reduction in fossil fuel deposits is making integration of renewable energy secure global attention. This paper therefore investigates the effect of high penetration of wind power on power loss and voltage profile of 52-bus, 330kV Nigerian grid. Modeling and simulation of the study were successfully done using the Continuation Power Flow method and Power System Analysis Toolbox in the Matrix Laboratory environment. The Ant Colony Optimization (ACO) technique codes were used to determine the best sites and sizes of Permanent Magnet Synchronous-based Wind Turbine Generators (PMS-WTGs) on the grid as nonoptimal placement and size of PMS-WTGs will result into active power losses and poor voltage profile. The ACO and power flow analysis indicated two load buses, Aladja bus and Yola bus as best sites for PMS-WTGs with optimal sizes of 100MW and 197MW respectively. The result shows a decrease in the system's active (42.1%) and reactive (43.9%) power losses while heightening voltage magnitudes of critical buses to statutory values and enhancing the grid power quality. The overall results indicate that integrating 297MW PMS-WTGs improves voltage stability and power loss reduction by maximizing system loadability and reducing line losses. [ABSTRACT FROM AUTHOR]

This research proposes a strategy to minimize the active power loss in the standard IEEE 85-node radial distribution power grid by optimizing the placement of wind turbines in the grid. The osprey optimization algorithm (OOA) and walrus optimization algorithm (WOA) are implemented to solve the problem. The two algorithms are validated in three study cases of placing two wind turbines (WTs) in the system for power loss reduction. Mainly, in Case 1, WTs can only produce active power, while in Case 2 and Case 3, WTs can supply both active and reactive power to the grid with different ranges of power factors. In Case 4, the best-applied methods between the two are reapplied to reach the minimum value of the total energy loss within one year. Notably, this case focuses on minimizing the total power loss for each hour in a day under load demand variations and dynamic power supply from WTs. On top of that, this case uses two different sets of actual wind power data acquired from the Global Wind Atlas for the two positions inherited from the previous case. Moreover, the utilization of wind power is also evaluated in the two scenarios: (1) wind power from WTs is fully used for all values of load demand, (2) and wind power from WTs is optimized for each load demand value. The results in the first three cases indicate that the WOA achieves better minimum, mean, and maximum power losses for the two cases than the OOA over fifty trial runs. Moreover, the WOA obtains an excellent loss reduction compared to the Base case without WTs. The loss of the base system is 224.3 kW, but that of Case 1, Case 2, and Case 3 is 115.6, 30.6 kW, and 0.097 kW. The placement of wind turbines in Case 1, Case 2, and Case 3 reached a loss reduction of 48.5%, 84.3%, and 99.96% compared to the Base case. The optimal placement of WTs in the selected distribution power grid has shown huge advantages in reducing active power loss, especially in Case 3. For the last study case, the energy loss in a year is calculated by WSO after reaching hourly power loss, the energy loss in a month, and the season. The results in this case also indicate that the optimization of wind power, as mentioned in Scenario 2, results in a better total energy loss value in a year than in Scenario 1. The total energy loss in Scenario 2 is reduced by approximately 95.98% compared to Scenario 1. So, WOA is an effective algorithm for optimizing the placement and determining the power output of wind turbines in distribution power grids to minimize the total energy loss in years. [ABSTRACT FROM AUTHOR]

The main aim of this work is to present a step-by-step procedure to model and analyze the power loss distribution of three-level Gallium Nitride (GaN) inverters. It has been applied to three distinct three-phase three-level voltage source inverters utilized in electric traction drives: Active Neutral Point Clamped, Neutral Point Clamped and T-Type Neutral Point Clamped. The proposed analytical power loss modelling, combined with an equivalent representation of the electrical machine proved to be a viable solution to achieve a time-saving and low computational burden simulation platform, leading to satisfying accurate results. This has been confirmed by comparing the results carried out from the simulations of a 110 kW permanent magnet synchronous motor drive and those determined by considering a simplified circuital representation based on the proposed analytical power loss modelling. [ABSTRACT FROM AUTHOR]

Summary: In the power electronics industry, reliability is of utmost importance to manufacturers. Power semiconductor devices are extensively utilized in multilevel inverters (MLIs), which results in increased failure probability. MLI structures have a significant impact on the system's overall reliability. MLIs with a high degree of reliability reduce system maintenance costs and improve efficiency and the life of the entire system. This paper presents a comprehensive evaluation of five‐level packed U‐cell (PUC5) inverter, modified five‐level PUC (MPUC5) inverter, and their fault‐tolerant (FT) variants with respect to reliability, degree of fault tolerance, power loss and efficiency, and cost. A more accurate reliability evaluation method is used in this work in which failure rates of each component of inverter topologies under healthy and post‐fault conditions are calculated. Hence, this method provides more accurate reliability function of an MLI topology as compared to other methods in which failure rates are assumed to be same for all switches. Typhoon HIL‐402 emulator is used to demonstrate the FT capabilities of topologies in hardware‐in‐the‐loop (HIL) environments. [ABSTRACT FROM AUTHOR]

Interconnected Microgrid (IMG) networks have been suggested as the best to build electrical networks in remote villages far from the main electricity grid by interconnecting the nearby distributed energy resources (DERs) through power electronic converters. Interconnecting different DERs results in voltage deviation with unequal power-sharing, while voltage performance is a significant challenge. The control strategies for these converters are essential in the operational stability of any IMG network under study. In this paper, we propose an improved droop control method aiming to manage the power flow among the IMGs by maintaining the constant desired voltages in the network with minimum voltage deviation, resulting in the minimization of power losses. We found that the minimum voltage deviation at the load side (converter-3) was between 0.58 and 0.56 V, while the voltage deviation for both converter-1 and converter-2 remained below 0.5 V. This leads to efficient voltage regulation, resulting in the stability of an IMG network. To verify the feasibility of this method, MATLAB/SIMULINK has been used. [ABSTRACT FROM AUTHOR]

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Power losses of switches and inductors are consistent challenges that hinder the development of high-frequency power supply in package (PSiP). This paper investigates the roadmap for power loss optimizations of switches and inductors in high-frequency PSiPs. Firstly, a size and parallel quantity design method to reduce power loss in an integrated Si LDMOSFET is provided with comprehensive consideration of switching frequency and power levels. Secondly, quality factors of different air-core inductors are analyzed with consideration of geometric parameters and skin effect, which provides the winding structure optimization to reduce power losses. The power losses of the integrated Si LDMOSFET and air-core inductors are both reduced to less than 10% of the output power at 1~100 MHz switching frequency and 0.1~10 W power level. Finally, based on the above optimizations, power losses of switches and inductors are calculated with switching frequency and power level. Combining the calculated results, this paper predicts the efficiency boundaries of PSiPs. Upon efficiency normalization with consideration of input and output voltage levels, all the predictions are consistent with the published literature. The efficiency predication error is 1~15% at 1~100 MHz switching frequency and 0.1~10 W power level. The above power loss optimizations improve the efficiency, which provides potential roadmaps for achieving high-frequency PSiPs. [ABSTRACT FROM AUTHOR]

The paper presents efficiency and power loss analysis in a high-frequency, seven-level diode-clamped inverter (7LDCB). The inverter is composed of four-level (4L) diode-clamped branches based on MOSFET transistors and Si Schottky diodes. The range of DC-link voltages enables the operation of the inverter in connection with a single-phase power grid. The tested inverter can be controlled using various modulation concepts that affect its parameters, but also energy losses. Carrier-based modulation, which may be useful in a few applications, is compared to selective modulation based on the state machine (SM-based) algorithm. The article demonstrates the efficiency level of the inverter as well as the influence of the modulation method and switching frequency on the efficiency and loss distribution in semiconductor devices. The article also shows the hardware implementation of a complex modulation algorithm based on selective switching states used to maintain voltage balance on three DC-link capacitors. Redundant switching states allow the generation of the same voltage but with the use of a selected DC-link capacitor. This makes it possible to balance the DC-link voltage with the load current. The article presents experimental results, which show the advantage of using the modulation method with selective switching states. First, it allows for equalizing the loading of DC-link capacitors. The second advantage is a more uniform distribution of losses in semiconductor components. [ABSTRACT FROM AUTHOR]

Restoration of service during faults to healthy zones and the minimization of true or real power losses are the main aspects of the satisfactory operation of an electrical distribution system (EDS). These objectives can be achieved with artificially intelligent optimisation techniques through electrical distribution system reconfiguration. The restoration of service is an important part of ensuring a stable power supply. If there is a fault with the EDS, the damaged zone is separated, and the healthy system is restored without breaching limitations. In the distribution system, ohmic losses are 25-35%. It is essential to reconfigure the system to reduce these losses. In this paper, a hybrid artificial rabbits' optimisation and improved mayfly optimisation (ARO-IMO) technique is adopted for restoration of service and loss minimization. The method being suggested will be carried out on an IEEE 4-feeder network for restoration of service and on IEEE 33 and 69 radial distribution networks (RDN) for diminution of losses. [ABSTRACT FROM AUTHOR]

An amalgamation of Green Distributed Generation (GDG) with Distribution Networks (DNs) was developed because its performance became more efficient and sustainable. It increased the challenges in the design and operation of the protection scheme and changed the short circuit current (SCC), voltage profile, power losses, and power flow direction after the GDG penetration. These changes rely on the number, size, location, and environmental influence according to the GDG type. Therefore, many researchers have discussed protection system challenges and presented types of protection approaches to find a robust protection layout for DNs integrated with GDGs to prevent the electrical equipment from being destroyed during abnormal conditions. This paper represents an exhaustive survey of GDG integration with DNs and its effects on protection design challenges. Furthermore, this paper summarizes the modern protection methods and detection technologies, along with their important aspects that have been accessed. One of the important and reliable methods is resetting and coordinating between protection devices (PDs) that operate in the same distribution feeder. This methodology focuses on restricting the main variables and parameters used in the PDs setting after the GDG is embedded to recalculate the suitable setting and coordination. Optimization techniques should be used to find the best setting or location of the protection system in the DNs, in addition to calculating the optimal GDG scale and location. However, international standards are used to specify the suitable equations that satisfy high protection system characteristics to ensure the DNs' reliability. [ABSTRACT FROM AUTHOR]

Modern induction cookers have started to demand challenging features such as slim design, high power ratings, high performance, and silence. All those requirements are directly related to the power semiconductors used in power converters. Si (silicon)-based power semiconductors are not capable of answering those demands because of strict operating conditions, such as high ambient temperatures. Therefore, WBG (Wide Band Gap) power semiconductors have been getting attention. In this study, WBG power semiconductors will be compared with Si-based IGBT (Insulated Gate Bipolar Transistor) under different operating conditions. The best option to use WBG power semiconductors in modern induction cookers will be analyzed. The performance of a series-resonant half-bridge converter was evaluated under various operating conditions. Measurements were obtained from the real operating conditions of induction hobs. The switching frequency is changed from 20 kHz to 100 kHz, while the power rating is increased to 3.7 kW. In addition to traditional 4-zone induction cooktops, this discussion also provides a comprehensive analysis of high-segment, fully flexible induction cooktops. While the IGBT-based design exhibits 25.79 W power loss per device, the WBG device exhibits 6.87 W in the maximum power condition of conventional induction cooker operation. When it comes to high-frequency operation, the WBG power device exhibits 10.05 W at 95 kHz. Total power loss is still well below that of the IGBT-based conventional design. Appropriate usage of WBG power semiconductors in modern induction cookers can exploit many more benefits than Si-based designs. [ABSTRACT FROM AUTHOR]

Accurate evaluation of power losses in a modular multilevel converter (MMC) is very important for circuit component selection, cooling system design, and reliability analysis of power transmission systems. However, the existing converter valve loss calculation methods using the nearest level modulation (NLM) method and the traditional sorting-based capacitor voltage balancing strategy are inaccurate since the submodule (SM) switching logics in the MMC arms are uncertain. To solve this problem, the switching principle of the SMs in the sorting-based voltage balancing strategy is analyzed. An accurate MMC power loss calculation method based on the analysis of loss distribution of various SM topologies, including half-bridge submodule (HBSM), full-bridge submodule (FBSM) and clamp double submodule (CDSM), is proposed in this paper. The method can accurately calculate the losses caused by the extra switching actions during the capacitor voltage balancing process, thus greatly increasing the calculation accuracy of switching losses compared with existing methods. Simulation results based on a practical ± 350 kV/1000 MW MMC-HVDC system with variety of MMC topologies with different voltage balancing strategies demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Congestion of the power system is the most common challenge an Independent System Operator (ISO) faces in restructured electricity markets. It affects the efficiency of the market when transmission lines are congested causing transmission costs to rise. To prevent transmission line congestion, ISO needs to take the necessary steps. To solve these issues, this paper introduces a new method namely the Adaptive Red Fox Optimization algorithm (ARFOA) to compute the congestion cost considering the power losses in the transmission line system. Initially, all the generators in the system are selected to reschedule real power outputs. Second, by establishing a proposed optimization issue, ARFOA is employed to control transmission line congestion. The implementation of the proposed method is evaluated on the IEEE 30 bus system. The algorithm's adaptability is tested using several case studies involving the base case and line outages, also compared with the other existing techniques such as PSO, ASO, and GSO approaches. The simulation outcomes indicate that the proposed strategy outperforms existing techniques in terms of congestion cost, power loss, generation rescheduled power, and computational time. [ABSTRACT FROM AUTHOR]

Power loss is influenced by uncertain and ever increasing loads in the system but can be minimized by network reconfiguration where the topological structure of the system is changed by altering the switching operation. In this work, a multi-objective framework through reconfiguration is formulated with loss minimization as primary objective and reliability and voltage profile improvement as secondary objectives. A binary particle swarm optimization (BPSO) base method is developed to reconfigure the network by fulfilling all distribution network constraints. The influence of the BPSO parameters to obtain the optimal switches with minimized power loss, reliability indices, and voltage deviations are studied by a faster convergence. The results have been compared for different weights of the objective to give a comprehensive understanding of the nature of the objective attempted in this work. IEEE 33 bus and radial IEEE 69 bus systems were considered for testing the proposed method. [ABSTRACT FROM AUTHOR]

The goal of this work is to reduce power loss and improve voltage profile by formulating the optimal DG placement problem as a restricted nonlinear optimisation problem. As a novelty, the proposed hybrid algorithm, referred to as Multifactor Update-based Hybrid Model (MUHM) is constructed by merging the concepts of Lion Algorithm (LA) & Sea Lion Algorithm (Sea Lion Optimization Algorithm (SLnO). The Forward-Backward Sweep (FBSM) Model is used to calculate the power loss. Three test cases are examined for the voltage profile & loss minimization in the feeder team with DGs: "case 1(DG supplying real power alone (P), case 2 (DG supplying reactive power alone (Q) and Case 3 (DG supplying both real and reactive power)". Application of the suggested method to various IEEE test systems, including IEEE 33, IEEE 123, and IEEE 69, respectively, is used to assess its efficacy. According, the results show that the presented work at loading percentage = 0 is 12, 15, 135, 4.65, and 8 superior to SFF, BBO, BAT, LA and SLnO, respectively. [ABSTRACT FROM AUTHOR]

Power distribution systems (PDS) comprise essential electrical components and infrastructure that facilitate the delivery of electrical energy from a power transmission system to end users. Typically, the topology of distribution systems is radial, so that power goes from the substations to end users through main lines or feeders. However, the expansion of new feeders to accommodate new users and ever-growing energy demand have led to higher energy losses and deterioration of the voltage profile. To address these challenges, several solutions have been proposed, including the selection of optimal conductors, allocation of voltage regulators, utilization of capacitor banks, implementation of distributed generation, and optimal reconfiguration. Although reconfiguring the network is the most cost-effective approach, this solution might not be sufficient to completely minimize technical losses and improve system performance. This paper presents a novel approach that combines optimal distribution network reconfiguration (ODNR) with optimal conductor selection (OCS) to minimize power losses and enhance the voltage profiles of PDS. The key contribution lies in the integration of the ODNR and OCS into a single MILP problem, ensuring the attainment of globally optimal solutions. The proposed model was tested with benchmark 33-, 69-, and 85-bus test systems. The results allowed us to conclude that the combined effect of ODNR and OCS presents better results than when any of these approaches are applied either separately or sequentially. [ABSTRACT FROM AUTHOR]

One of the most famous methods for minimizing power loss is distribution network reconfiguration (DNR). Accordingly, many researchers have focused their work on finding a network's optimal configuration in planning mode. However, few address the switching sequence process during operation mode. This paper introduces an innovative approach to minimize power loss in distribution networks. It addresses the often-overlooked real-time switching sequence order (SSO) during network operation, ensuring a smooth transition to the optimal configuration within operational constraints. Simultaneously, it optimizes distribution network reconfiguration (DNR) and distributed generation location and sizing (DG-LS) to maximize load capacity. The primary goal is to reduce power losses, improve voltage profiles, and enhance network efficiency. Utilizing multi-objective decision methods based on AHP, particle swarm optimization (PSO), and firefly algorithm (FA), this study achieves efficient results for SSO, DNR, and DG-LS optimization. [ABSTRACT FROM AUTHOR]

Optimal power flow (OPF) is one of the most widely studied problems in the field of operations research, as it applies to the optimal and efficient operation of the electric power system. Both the problem formulation and solution techniques have attracted significant research interest over the decades. A wide range of OPF problems have been formulated to cater for the various operational objectives of the power system and are mainly expressed either in polar or rectangular voltage coordinates. Many different solution techniques falling into the two main categories of classical/deterministic optimization and heuristic/non-deterministic optimization techniques have been explored in the literature. This study considers the Volt/VAR optimization (VVO) variant of the OPF problem formulated in rectangular voltage coordinates, which is something of a departure from the majority of the studies, which tend to use the polar coordinate formulation. The heuristic particle swarm optimization (PSO) and the classical primal-dual interior-point method (PDIPM) are applied to the solution of the VVO problem and a comparative analysis of the relative performance of the two algorithms for this problem is presented. Four case studies based on the 6-bus, IEEE 14-bus, 30-bus, and 118-bus test systems are presented. The comparative performance analysis reveals that the two algorithms have complementary strengths, when evaluated on the basis of the solution quality and computational efficiency. Particularly, the PSO algorithm achieves greater power loss minimization, whereas the PDIPM exhibits greater speed of convergence (and, thus, better computational efficiency) relative to the PSO algorithm, particularly for higher-dimensional problems. An additional distinguishing characteristic of the proposed solution is that it incorporates the Newton–Raphson load flow computation, also formulated in rectangular voltage coordinates, which adds to the efficiency and effectiveness of the presented solution method. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid algorithm using a hybrid firefly and particle swarm optimization (HFPSO) algorithm to determine the optimal placement of STATCOM devices. A multi-objective function is used to increase voltage stability, voltage profile and minimize overall power losses of the transmission system. At first, PSO algorithm is used to find the optimal STATCOM location and further more to reduce the power losses and voltage profile enhancement to overcome the sub-optimal operation of existing algorithms, the HFPSO algorithm is used to determine the optimal placement of STATCOM FACTS device and verification of the proposed algorithm was achieved on standard IEEE 14-bus and 30-bus transmission systems in the MATLAB environment. Comprehensive simulation results of two different cases show that the proposed HFPSO demonstrates significant improvements over other existing algorithms to enhance voltage stability and reducing active and reactive power losses in an electrical power transmission systems. [ABSTRACT FROM AUTHOR]

In this paper, a stochastic multi-objective intelligent framework (MOIF) is performed for distribution network reconfiguration to minimize power losses, the number of voltage sags, the system's average RMS fluctuation, the average system interruption frequency (ASIFI), the momentary average interruption frequency (MAIFI), and the system average interruption frequency (SAIFI) considering the network uncertainty. The unscented transformation (UT) approach is applied to model the demand uncertainty due to its being simple to implement and requiring no assumptions to simplify it. A human-inspired intelligent method named improved mountaineering team-based optimization (IMTBO) is used to find the decision variables defined as the network's optimal configuration. The conventional MTBO is improved using a quasi-opposition-based learning strategy to overcome premature convergence and achieve the optimal solution. The simulation results showed that in single- and double-objective optimization some objectives are weakened compared to their base value, while the results of the MOIF indicate a fair compromise between different objectives, and all objectives are enhanced. The results of the MOIF based on the IMTBO clearly showed that the losses are reduced by 30.94%, the voltage sag numbers and average RMS fluctuation are reduced by 33.68% and 33.65%, and also ASIFI, MAIFI, and SAIFI are improved by 6.80%, 44.61%, and 0.73%, respectively. Also, the superior capability of the MOIF based on the IMTBO is confirmed compared to the conventional MTBO, particle swarm optimization, and the artificial electric field algorithm. Moreover, the results of the stochastic MOIF based on the UT showed the power loss increased by 7.62%, voltage sag and SARFI increased by 5.39% and 5.31%, and ASIFI, MAIFI, and SAIFI weakened by 2.28%, 6.61%, and 1.48%, respectively, compared to the deterministic MOIF model. [ABSTRACT FROM AUTHOR]

In radial distribution networks, the unreasonable use of distributed generators (DGs) will enhance the effects of voltage quality reduction and network loss. Consequently, the optimal allocation of distribution groups (OADG) has far-reaching implications for the economical, secure, and stable operation of radial distribution networks. The purpose of the study on the optimal allocation of distributed generators is to allocate the locations and capacities of DGs scientifically and rationally, enhance voltage quality, and reduce power loss. This paper proposes an enhanced ISC-SSA algorithm with constraint strategy for the OADG problems, which addresses the disadvantages of traditional salp swarm algorithm (SSA), such as low solution accuracy and slow convergence speed, and introduces a sine cosine algorithm (SCA) to optimise the salp swarm followers. To reduce the limitation of only the leader guiding the followers for position updates, a symbiotic strategy with multiple subpopulations is introduced to simulate the sharing of information of the salp swarm population, relying on the decision-maker and the leader to jointly guide the population movement, thereby increasing the global optimization-seeking capability of the algorithm, and the method is implemented in IEEE-33, IEEE-69, and IEEE-119 systems. In addition, the paper extends the ISC-SSA algorithm to the MOISC-SSA algorithm to solve in IEEE-33, IEEE-69 test systems the multi-objective OADG problems. Multiple sets of simulation results demonstrate that the proposed method solves radial distribution system problems of varying sizes with greater search precision and greater significance. [ABSTRACT FROM AUTHOR]

Virtual power plants (VPPs) are a critical technology for distribution systems that can integrate various renewable energy resourcescontrollable loads and energy storage systems into one specific power plant through a distributed energy management system. This paper proposes a coordinated dispatch optimization model between the main grid and VPPs aiming to minimize both the power generation cost and total system active loss. When the time of the equivalent dispatching model is not divisible due to the existence of a time coupling constraint inside the VPPs, this model can obtain the global optimal solution through iteration between the main grid and the VPPs. By employing multi-parametric quadratic programming to obtain accurate critical domains and optimal cost functions, the convergence speed and stability are significantly improved. Additionally, a reactive power and voltage optimization technique leveraging the generalized Benders decomposition is presented for the coordination of the main grid and the VPPs. Moreover, the impact of distributed energy resource (DER) clusters on the main grid was studied, from which we proved that the proposed approach can expeditiously abate energy production expenditure and system active dissipation whilst enhancing the system equilibrium. [ABSTRACT FROM AUTHOR]

The power loss estimation of a gallium nitride enhancement-mode high electron mobility transistor (GaN E-HEMT) is necessary to optimize a thermal model of a power conversion system. However, many manufacturers do not provide a switching energy in their datasheets. To estimate switching energy using information provided in the datasheet, the parasitic capacitance of the GaN E-HEMT is utilized. The switching loss of the GaN E-HEMT can be easily obtained with a conventional method. However, this process does not consider nonlinearity of the parasitic capacitance, which results in large errors and makes thermal model optimization impossible. This paper proposes an enhanced switching loss calculation model considering the non-linear parasitic capacitances of a GaN E-HEMT. To obtain accurate switching energy, a second-order exponential function using regression analysis is used to model the non-linear parasitic capacitance of the GaN E-HEMT. A theoretical analysis of the proposed method has been discussed. Then a double pulse test (DPT) has been performed to verify the proposed method. The proposed method almost corresponds to the experimental results within ± 20%, and it provides a simple and intuitive capacitance model. [ABSTRACT FROM AUTHOR]

To improve the power utilization efficiency of distributed energy units (DEUs) in DC microgrids, a centralized current iteration regulation approach is presented in this paper. The power utilization efficiency is partially represented by the power losses of DEUs, which can be modelled as quadratic functions of the output currents of DEUs. The power efficiency is also dependent on the line losses on the resistances between the DEUs and DC buses, which can be formulated in the basis of the output currents as well. Thus, the total power losses of DEUs comprise line and converter losses, which are verified to be a constrained‐convex function of the current allocation coefficients. In this paper, a primal‐dual subgradient method (PDSM) using only explicit addition and subtraction iterations is adopted to obtain the optimal current distribution coefficients. On this basis, an adaptive droop regulation scheme is applied to further control the output voltage references of DEUs, and proportional‐integral (PI) controllers are applied to track the adaptive voltages based on the current sharing errors. Both simulation and empirical results demonstrate the effectiveness of the proposed control to improve the power utilization efficiency of DEUs regardless parameter and load variations in DC microgrids. [ABSTRACT FROM AUTHOR]

In this work, we present an analytical model of dynamic power losses for enhancement-mode AlGaN/GaN high-electron-mobility transistor power devices (eGaN HEMTs). To build this new model, the dynamic on-resistance (Rdson) is first accurately extracted via our extraction circuit based on a double-diode isolation (DDI) method using a high operating frequency of up to 1 MHz and a large drain voltage of up to 600 V; thus, the unique problem of an increase in the dynamic Rdson is presented. Then, the impact of the current operation mode on the on/off transition time is evaluated via a dual-pulse-current-mode test (DPCT), including a discontinuous conduction mode (DCM) and a continuous conduction mode (CCM); thus, the transition time is revised for different current modes. Afterward, the discrepancy between the drain current and the real channel current is qualitative investigated using an external shunt capacitance (ESC) method; thus, the losses due to device parasitic capacitance are also taken into account. After these improvements, the dynamic model will be more compatible for eGaN HEMTs. Finally, the dynamic power losses calculated via this model are found to be in good agreement with the experimental results. Based on this model, we propose a superior solution with a quasi-resonant mode (QRM) to achieve lossless switching and accelerated switching speeds. [ABSTRACT FROM AUTHOR]

The reliability of electrical systems is a critical operational characteristic for distribution companies. On the other hand, they pay great attention on reducing losses in primary and secondary distribution lines. In this article, a modified Jellyfish Search (MJFS) algorithm is presented for handling Optimal Network reconfiguration (ONR) in Medium Voltage Distribution Feeders (MVDFs). An ONR formulation is proposed for reliability enhancement and power loss reduction in a multi-objective model where three reliability measures are incorporated which are total energy not supplied (TENS), system average interruption unavailability index (SAIUI) and system average interruption frequency index (SAIFI). The proposed MJFS expands on the JFS searching benefits by introducing a quasi-oppositional-based learning and social neighborhood strategies. Also, a proposed bus-line feeding matrix (BLFM) is incorporated to develop the MJFS. Through the BLFM, each distribution line is simulated as an outage and the regarding distribution nodes which are not supplied is estimated. The simulation results are performed on a large-scale IEEE MVFD of 137-bus which derive significant improvements of the proposed MJFS over the standard JFS algorithm. Considering the proposed multi-objective model, the proposed MJFS achieves great reduction in power losses, TENS, SAIUI and SAIFI with 44.42, 30.57, 30.78 and 23.92 %, respectively compared to the initial case. Also, versus the standard JFS, grey wolf optimizer, tuna swarm optimization, equilibrium optimizer and tunicate swarm optimization, the proposed MJFS acquires great reduction in the standard deviation with improvement of 2.5, 92.51, 10.67, 91.53 and 96.51%, respectively. [ABSTRACT FROM AUTHOR]

The need for electrical energy is increasing in line with the increase in population and increasing progress in welfare. On the other hand, the availability of fossil fuels as the main fuel in generating electricity is dwindling; so, there is a need for policies that require the use of environmentally friendly renewable energy. The utilization of renewable energy does not necessarily apply freely due to several constraints. One effort is a generator or distributed generation (DG) which is placed in the distribution line close to the load. The utilization of DG must go through planning, especially the large capacity and position on the bus and on the feeder, which will result in small network losses and a voltage profile that meets tolerance limits. Thus, the purpose of this study is to optimize to obtain the capacity and location of the DG calculated by considering the variation in the load through the genetic algorithm method. As a result, the optimal DG position for normal load is obtained on bus 18, bus 20, and bus 32 with capacities of 190 kW, 463 kW, and 370 kW, respectively. The losses obtained decreased from 54.6733 kW to 9.9447 kW, and the voltage profile was maintained within the specified limits. Optimization was carried out for decreasing and increasing loads in percent. The result is that losses can be minimized, and the voltage profile remains within the required limits. The lower the load, the more stable the voltage and the smaller the losses; meanwhile, the larger the load, the more fluctuating the voltage is, but still within the limits specified in the optimization. [ABSTRACT FROM AUTHOR]

Present-day power systems have highly complex and stressed operating conditions owing to insufficient reactive power to meet the required power demand. This leads to increased real power and reactive power losses, as well as voltage instability within a power system. To achieve the flexible operation of the power system, Flexible Alternating Current Transmission System (FACTS) devices have been employed. The optimal location of FACTS devices influences the system's performance and significantly affects line/bus reactive power flows. Consequently, the line or bus voltage profiles have been improved, leading to a reduction in power losses. Particle Swarm Optimization (PSO) heuristic methods and HFPSO Hybrid heuristic methods have been used to identify the weakest bus/branch for the suitable placement of UPFC devices, improving voltage stability. This paper discusses a more significant reduction in power losses in a MATLAB environment. Flexible Alternating Current Transmission System (FACTS) devices address reactive power challenges in power systems and enhance operational flexibility. Strategic placement using Particle Swarm Optimization (PSO) and HFPSO Hybrid methods identifies weak points, optimizing Unified Power Flow Controller (UPFC) placement for improved voltage stability. UPFC integration strategically reduces real and reactive power losses, improving power transmission efficiency. This enhances line and bus voltage profiles, addressing instability and significantly reducing overall power losses. The paper offers a detailed analysis of the power system, highlighting the synergy between FACTS devices, heuristic optimization, and power loss reduction. Simulations in MATLAB validate the proposed methodology, demonstrating a noteworthy improvement in power system performance. [ABSTRACT FROM AUTHOR]

Integrating distributed generations (DGs) into the radial distribution system (RDS) are becoming more crucial to capture the benefits of these DGs. However, the non-optimal integration of renewable DGs and shunt capacitors may lead to several operational challenges in distribution systems, including high energy losses, poor voltage quality, reverse power flow, and lower voltage stability. Therefore, in this paper, the multi-objective optimization problem is expressed with precisely selected three conflicting goals, incorporating the reduction in both power loss and voltage deviation and improvement of voltage stability. A new index for voltage deviation called root mean square voltage is suggested. The proposed multi-objective problems are addressed using two freshly metaheuristic techniques for optimal sitting and sizing multiple SCs and renewable DGs with unity and optimally power factors into RDS, presuming several voltage-dependent load models. These optimization techniques are the multi-objective thermal exchange optimization (MOTEO) and the multi-objective Lichtenberg algorithm (MOLA), which are regarded as being physics-inspired techniques. The MOLA is inspired by the physical phenomena of lightning storms and Lichtenberg figures (LF), while the MOTEO is developed based on the concept of Newtonian cooling law. The MOLA as a hybrid algorithm differs from many in the literature since it combines the population and trajectory-based search approaches. Further, the developed methodology is implemented on the IEEE 69-bus distribution network during several optimization scenarios, such as bi- and tri-objective problems. The fetched simulation outcomes confirmed the superiority of the MOTEO algorithm in achieving accurate non-dominated solutions with fewer outliers and standard deviation among all studied metrics. [ABSTRACT FROM AUTHOR]

As the load on distribution networks grows, system operators and planners are constantly challenged with the issue of voltage regulation or enhancing the quality of supply to customers at the load end of lengthy distribution lines. This paper presents the optimum determination of series capacitor units in a distribution system to maximize energy‐saving and enhance voltage levels. Interestingly, series capacitors can enhance the capability of transmission lines, reduce line losses, enhance the performance of buses with large induction motor loads and reduce voltage flicker. At the same time, the limitations of series compensation are taken into consideration while calculating its optimum values. To achieve the planning objective and optimal load flow objective, two strategies: The Improved Grey Wolf Optimization method (I‐GWO) and Tabu Search (TS), are hybridized to get the benefit of their advantages. The I‐GWO has a movement strategy called dimension learning‐based hunting for enhancing the balance between global and local search and maintaining diversity. The proposed (I‐GWO‐TS) algorithm can solve mixed‐integer programming to achieve the planning and the optimal load flow objectives. The proposed method can be applied to a real Egyptian distribution system that is heavily loaded, with poor voltage regulation, and also has high‐power losses. The obtained results demonstrate the capability of the proposed approach to determine optimal series capacitors' location and sizing for maximization of energy saving. Further, the proposed method improves the network performance regarding the voltage profile and power losses, although the limitations of including series compensation were considered in the distribution system. [ABSTRACT FROM AUTHOR]

Voltage control and power loss minimization are some of the crucial issues in distribution system energy management. Finding the best strategy for Voltage control and power loss reduction is a critical task for the distribution network operator (DNO). The main contributions of the proposed work are (i) determination of size and location of the Distribution Static Synchronous Compensator (DSTATCOM) with (OLTC). (ii) to minimize the power loss and Voltage deviation with the Volt/var control strategy. (iii) To obtain the impact of single and multiple D-STATCOM units with and without OLTC. The proposed method is tested on two test systems: (i) IEEE-69 RDS and (ii) IEEE-25 bus three-phase unbalanced system. The benefits of the proposed results are addressed in the reduction of power loss, enhancement of the Voltage profile, and the annual cost of saving for the DNO. The results are tabulated, verified, and compared with other methods. The power loss is reduced to 39.25%, 38.04% for 69 bus and 25 bus test systems. The minimum Voltage profile is enhanced from 0.90918 pu to 0.9619 pu for 69 bus RDS and from 0.922559 pu to 0.9747 pu for 25 bus three-phase system. [ABSTRACT FROM AUTHOR]

This paper introduces a mathematical design and analysis of three-phase inverters used in electric drive applications such as aerospace, electric vehicles, and pumping applications. Different wide bandgap (WBG) semiconductor technologies are considered in this analysis. Using SiC MOSFETs and Si IGBTs, two drive systems are developed in order to show the improvement in the efficiency of the inverter. The efficiency, total losses of the drive systems and the power losses of two inverters are computed and compared for both drive systems at the same operating condition. The drive system with SiC MOSFET shows much better performance compared to the drive system with Si IGBT. The SiC MOSFET system provides a 59.39%, 86.13%, and 29.76% lower conduction losses, switching losses and drive's total losses, respectively, compared to the Si IGBT system. The efficiency of the SiC MOSFET system is 2.46%pu higher than the efficiency of the Si IGBT drive system. Moreover, this paper introduces a detailed analysis for the dc-link voltage and current ripples in three-phase inverters. Furthermore, the minimal dc-link capacitor needed to deal with the ripple current and voltage is investigated. Finally, the performance of the drive with Si IGBT is experimentally tested under different operating speeds and loads. [ABSTRACT FROM AUTHOR]

A distribution system's network reconfiguration (NR) is the process of changing the status of the switches to change the topology of the feeders. Using optimal NR at various network load levels, this research proposed an economical way for improving the voltage profile and reducing power loss in distribution systems. A new metaheuristic Heap-based optimizer based on the corporate rank hierarchy is used to solve the optimization problem in order to find the optimal radial distribution network. The objective functions used in this article include voltage profile improvement, power loss reduction, reduction of operation cost, and minimization of gas emissions. This novel technique provides accurate results while avoiding the issue of premature convergence and requires fewer control parameter settings. The proposed method is evaluated at three different load levels on a standard IEEE 33-bus test system, and the simulation results are compared to those of other optimization methods published in the literature, demonstrating that the proposed method improves the system voltage profile while minimizing losses and power costs, establishing that this technique is effective in finding the best result. The Wilcoxon and Friedman tests are also used to verify the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive multi-objective-based optimization problem formulation for finding the optimum size, site, and number of inverter-based DGs (IBDGs) for the operation of the distribution system so as to minimize annual energy cost comprising of costs for the energy loss during the normal operating state, running the IBDGs, substation power including penalty for reverse power flow (if any) and the average energy not supplied as a measure of reliability. Besides, the cost of average apparent load disturbed as a result of voltage sags during faults is also considered. The method is tested on the 33-bus distribution test system using particle swarm optimization. The results so obtained, demonstrate the effectiveness and applicability of the proposed formulation to find the optimum location(s), size(s), and number of IBDG(s) in the radial distribution system with appropriate constraints consideration. [ABSTRACT FROM AUTHOR]