This study investigates the IEEE 69-bus distribution network with three wind turbines (WTs) connected at the same buses of three battery energy storage systems (BESSs), with three 20- or 30-outlet electric vehicle charging stations (EVCSs) for charging electric vehicles (EVs). The honey badger algorithm (HBA) is adopted to minimize daily energy loss. The HBA determines the best size and position for three WT-BESS buses and three EVCS buses. The HBA calculates BESS size and operation mode to minimize daily energy loss. The demand of EVCSs varies throughout the day depending on the random choice of the number and state of charge of EVs entering the station. This results in the active and reactive energy losses and utility input energy decreasing by 63.5%, 60.6% and 59.6%, respectively, and the minimum voltage increasing from 0.9256 to 0.9839 pu. The network voltage profile and stability are also improved.

The voltage-sag is one of the crucial measures of power quality of electric distribution networks. Among the causes of voltage sag is simultaneously starting of water-pumping motors (WPMs). The key contributions of the present study are optimal sizing and control parameters of the supercapacitor energy storage (SCES) scheme to mitigate the voltage-sag caused by simultaneous start-up of WPMs fed by a real Karot distribution feeder (KDF) based on a recently-developed Walrus Optimizer (WO). The KDF is located in Upper Egypt to supply sixteen 30-hp induction-driven WPMs along with domestic loads. It is considered a case study to demonstrate the success of the proposed SCES in minimizing the KDF's voltage-sag. The WO is assigned to evaluate the optimal size of SCES as determined by its capacitance and voltage. The performance of the WO is compared with that of the particle swarm optimization (PSO) algorithm. For evaluating the effectiveness of the proposed SCES in minimizing the voltage-sag problem in the KDF, a comparison is made against the superconducting magnetic energy storage (SMES). The proposed SCES with capacity of 0.1 MJ and capital cost of 55.4 $ successfully reduced the voltage-sag to reach allowable limits against 0.625 MJ and 1736 $ on using the SMES.

The increasing demand for high-quality power conversion in industrial applications has led to advancements in multilevel inverter design and control. This paper presents a design and experimental implementation of a 3-level T-type neutral-point clamped (TNPC) inverter utilizing space vector pulse width modulation (SVPWM) and model predictive control (MPC) for optimized switching state selection. The proposed approach ensures DC-link voltage balance, symmetrical load voltage and current, reduced voltage harmonics, and uniform stress distribution among the inverter’s three legs. An LCL filter is integrated based on phase margin optimization criteria to maintain total harmonic distortion (THD) of the current within acceptable limits. Real-time stress monitoring circuits are developed to assess key parameters including on-state voltage, case temperature, and collector current, which are essential for the reliability analysis of the IGBT modules. The configuration is validated through laboratory experimentation and the use of a highly inductive load with currents of up to 100 A. Findings indicate uniform voltage and current distribution, reduced harmonics of less than 0.1% for current and 5% for voltage, under full load conditions, and enhanced dynamic performance and system reliability, making the proposed method suitable for high-quality industrial applications. Furthermore, the developed experimental setup with uniform stress distribution simplifies the TNPC-IGBT module reliability assessment using a one-leg equivalent circuit to estimate the lifespan and conduct reliability analysis, rather than analyzing the module’s three legs.

To address the dual concerns of environmental degradation and occupational health risks associated with emissions from traditional paving methods, this study investigates the use of Fiber-Reinforced Rubberized Concrete (FRRC) as a sustainable alternative for rigid pavement construction. A total of 238 concrete specimens incorporating recycled rubber and different types of fibers were tested to develop eco-friendly and durable pavement materials. Key performance metrics included ultrasonic pulse velocity (UPV) and abrasion resistance, with a focus on acoustic damping, long-term durability, and maintenance efficiency. The influence of repeated thermal cycling was also evaluated to replicate real-world service conditions. The results showed that the incorporation of rubber and fibers significantly improved both UPV and abrasion resistance. Furthermore, FRRC demonstrated better performance retention after thermal exposure compared to conventional concrete, highlighting its potential for use in green infrastructure. This approach promotes the recycling of waste materials and contributes to safer working environments by reducing harmful emissions on construction sites.

Seismic pounding between closely spaced buildings during earthquakes becomes increasingly severe when structures exhibit asymmetrical configurations or misaligned centers of mass and stiffness. Multi-directional seismic forces amplify stresses in such unbalanced buildings, highlighting the necessity to consider both structural movement and irregular geometries or eccentric loadings when determining adequate separation distances. This study investigates the seismic response of two adjacent buildings with off-center floor layouts subjected to various collision scenarios, focusing specifically on asymmetric impacts. The analysis emphasizes seismic forces acting laterally in the x-direction, evaluating configurations with different bidirectional eccentricity combinations (ex, ey). Four eccentricity cases were considered: (+ ex, + ey), (− ex, + ey), (− ex, − ey), and (+ ex, − ey). Nonlinear time history analyses were performed on structural models across three distinct collision scenarios. Nonlinear dynamic analyses and three-dimensional finite element modeling using ETABS software were employed to simulate the interaction between neighboring structures with asymmetric configurations under earthquake loading. Structural response demands including lateral displacements, torsional rotations, and accelerations were compared across cases. Results indicate that the bidirectional eccentricity parameters of adjacent buildings significantly influence seismic response demands. Specifically, asymmetric collisions between buildings with bidirectional eccentricities under x-direction seismic excitation markedly affect their seismic behavior, emphasizing the need to account for such eccentricities in design and evaluation.

Monitoring the peak junction hotspot temperature in IGBT modules is critical for ensuring the reliability of high-power industrial multilevel inverters, particularly when operating under extreme thermal conditions, such as in traction applications. This study presents a comprehensive chip-level analytical loss and thermal model for estimation of the peak junction hotspot temperature in a three-level T-type neutral-point-clamped (TNPC) IGBT module. The developed model includes a detailed analytical assessment of conduction and switching losses, along with transient thermal network modeling, based on the actual electrical and thermal characteristics of the IGBT module. Additionally, a hybrid thermal–electrical stress experimental setup, designed to replicate real operating conditions, was implemented for a balanced three-phase inverter circuit utilizing a Semikron three-level IGBT module, with testing currents reaching 100 A and a critical case temperature of 125 °C. The analytically estimated module losses and peak junction hotspot temperatures were validated through direct experimental measurements. Furthermore, thermal simulations were conducted with Semikron’s SemiSel benchmark tool to cross-validate the accuracy of the thermo-electrical model. The outcomes show a relative estimation error of less than 1% when compared to experimental data and approximately 1.15% for the analytical model. These findings confirm the model’s accuracy and enhance the reliability evaluation of TNPC-IGBT modules in extreme thermal environments.