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This paper presents a modelling of a high-frequency full bridge inverter for wireless power transmission (WPT) in Electric Vehicle (EV) charging applications. The inverter is designated at an operating frequency as high as 13.56 MHz in line with regulations for the industrial, scientific, and medical radio band (ISM band). Since the power is transferred wirelessly from the source to the EV, a coupling capacitive was used as a transmitter and receiver of the system. In this paper, the inverter model was simulated and analysed using LTSpice software. Different load changes and power are injected into the system. Furthermore, in order to obtain a robust system, the switching frequency of 13.56 MHz is used with some Dead Time (DT). The system already uses GaN MOSFETs for reliability and performance at high frequencies, in addition to LC impedance matching. The result is that by operating at a resonant frequency of 13.56 MHz with a resistive load of 50, it is obtained with a power of 2.3 kW that has been successfully transmitted with an efficiency of 89%.

This research offered a comparison of hydraulic (HPS) and electro-hydraulic power steering (EHPS) hydraulic pressure characteristics. The goal is to assess the potential for energy savings if an electric motor replaces hydraulic pressure. The purpose is to calculate the potential energy efficiency if an electric motor replaces hydraulic pressure. For this comparison, HPS and EHPS were both modeled. A PI controller was developed based on these models to regulate the steering wheel position and angular motor speed. In addition, the systems are compared by using the same input reference and transient response system, and the energy consumption is computed. Thus, with the installation of an electric motor in the power steering, it has a good response, functions in an optimal region, stabilizes, and has a 59.95% increase in energy efficiency.

This paper presents a comprehensive investigation utilizing simulations to analyze the peak force and energy absorption characteristics of cylindrical configurations, as well as a novel spiral crash box design inspired by the albuca spiralis form. The study aims to evaluate the behavior of these designs in low-speed collisions by utilizing aluminum and steel as two different materials. Four primary forms of thin-walled structures, including concentric circles, tangent circles, half-balanced circles, and spiral circles, were thoroughly examined using finite element analysis. Mesh-independent tests were conducted to ensure the accuracy of the simulation results, and various crumple displacements were compared to determine the optimal mesh sizing. The numerical results demonstrate a significant reduction in peak force for the aluminum crash box, with a remarkable 60% decrease compared to the steel crash box. Furthermore, the spiral shape, identified as an optimized design, exhibits a low peak force of only 118.42 kN and offers superior energy absorption of 9.15 kJ per kilogram compared to the other designs. Consequently, employing nature-inspired designs provides substantial benefits for enhancing crashworthiness in energy-absorbing devices.

MOSFETs are used in electronic circuits because they have high switching efficiency. Typically, MOSFETs are wired in parallel for applications that require high power. Theoretically, this circuit can multiply the current capability of parallel MOSFETs. However, even if all the MOSFETs in a parallel circuit have the same serial number and manufacturer, they might not necessarily have the same current characteristics. This could lead to issues with current imbalances, potentially causing harm to the MOSFETs, especially under severe circumstances. This study introduces a new Active Gate Driver (AGD) technique to balance the current in a parallel MOSFET circuit. The current difference can be used to modulate each MOSFET duty cycle. Specifically, the MOSFET with the smallest current capacity is configured as the Master, while the MOSFET following it is designated as the Slave. The interrupt time value for the duty cycle of each Slave MOSFET is influenced by the current differential between the Master and Slave. Consequently, different duty cycles for the Master and Slave MOSFETs can maintain the same current level. Based on the results of experiments conducted on three MOSFETs, it is evident that the AGD approach can effectively balance the current to an optimum level.

In this paper, the characterization of the supercapacitor is carried out, especially for applications in electric vehicles regenerative braking. Supercapacitors (SC) are explored in terms of self-discharge, and different charge-discharge currents. Supercapacitor testing has been carried out for charging, discharging, and self-discharge testing using the BCAP3000 P270 supercapacitor with a voltage of 2.7 V and a rated capacitance of 3250 F. The experiments were conducted using either a single supercapacitor or a pack of supercapacitors. On the basis of the estimated charge-discharge time, the results of the charge-discharge test will be compared. According to the findings of the SC charging and discharging tests, there are variances in the computation of the charging and discharging time ranging from 5.33% to 32.19%. The self-discharge test shows that for 40 days, the supercapacitor cell voltage drops from 2.7 V to 1.819 V.