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Integrating renewable energy resources into the existing generation capacity can handle the additional load resulting from the EV charging system, even when the majority of the EVs are charged during off-peak hours. This paper comprehensively analyzes EV charging methods with a particular focus on both grid-based direct charging and the utilization of renewable energy sources. However, the most practical approach for EV charging is through large-scale grid-based renewable energy stations. This study outlines the significant challenges facing the application of EV chargers. Overcoming these challenges is vital for the widespread adoption of new technologies such as Wireless power transfer charging systems in the EV sector. Wireless charging technology still faces several issues, such as energy loss during transmission, alignment between the coils, and quick and safe power delivery. One of the significant challenges facing wireless chargers is the need to optimize efficiency while ensuring convenient and reliable charging as outlined in this study. Different wireless charger configurations are presented for stationary EV charging systems by incorporating photovoltaic systems into charging stations and supervisory bases. The application of series-series wireless charger system as an emerging technology for EV chargers is analyzed and simulated as a recommended solution for EV wireless chargers. The system overall efficiency is approximately 98%. The charging system can operate reliably by mitigating the effects of load and grid disturbances.

A decentralized control approach is introduced in this paper that utilizes passivity-based control for two DC-distributed energy sources supplying the power of a load. Considering the concept of passivity, if each distributed generator exhibits passivity, this property will be maintained when these generators are connected in series or parallel. Thus, the stability of the entire system is guaranteed through the implementation of an interconnection and damping assignment passivity-based control (IDA-PBC). Additionally, droop voltage control is employed to achieve current sharing among the two power sources. If the model used is not an accurate representation of the original system, the controlled system may experience steady-state errors. To address these modeling errors, a compensation term is employed as the desired output voltage. The effectiveness of the proposed methodology is confirmed via results from simulation in three cases in which the performance of the system is investigated in start-up and load resistance or nominal load current change. With PBC, the system maintains stable operation. Experimental results validate the simulation results. Moreover, the proposed method guarantees global stability without knowing the parameters to prove global stability with local control.

Considering the importance of education especially for the newer field of education, the current study proposes a novel teaching method based on storytelling that aims to enhance the creativity of students and improve the effectiveness of learning. The method was applied and analyzed through a one-year teaching course case study to introduce topics regarding renewable energy. Despite traditional education, in which learning occurs through the direct transfer of information, here a plot with the theme of mountaineering and nature using real photos and narration of a fictional story was set for the implementation of the proposed method. Therefore, the unintentional consequences of conventional teaching including quick content forgetting, failure to define the main purpose, improper reaction, and low attractiveness and even effectiveness were prevented. Considering the affective and cognitive domains of Bloom’s Taxonomy as well as analyzing the performances of students during the teaching course and their final feedback, the results showed promising improvements including more participation (100%), better retention of content (receiving (75%) and remembering (83.33%)). While the learners preferred the proposed method and found it more effective (75%) and attractive (79.17%) than conventional teaching. Moreover, it was shown that the proposed method can improve education criteria in other affective and cognitive domains and is recommended to be considered for implementation in other complex engineering topics.

This study investigates the commandability in a DC-DC converter for fuel cell applications. In this modular system, each module is established on a three-level converter. The operation areas of the studied converter in terms of commandability have already been investigated. In this paper, a manner to increase the commandable area is suggested. An anti-windup scheme is used to enhance stability under duty-cycle saturation. An indirect sliding-mode controller is utilized to balance DC voltages and control currents with dynamical properties regardless of the operating settings. Simulations and experiments consistent to the theoretical study are conducted to confirm the suggested scheme.

Permanent Magnet Synchronous Motors (PMSMs) are used in a variety of industries, including aerospace, industrial control, and electric vehicles (EVs). Extensive research has been dedicated to the control and drive of PMSMs, with field-oriented control (FOC) gaining prominence in today’s industry. Despite its popularity, the nonlinear nature of the PMSM drive system impacts the dynamic performance when employing the traditional Proportional-Integral (PI)-based FOC method, particularly under varying operating points. Over the last decade, flatness-based control has emerged as a viable alternative to PI-based FOC in response to system nonlinearity. As a traditional approach, a cascaded flatness-based control structure has been proposed in the literature. This method, however, has lower dynamic performance due to its cascaded structure. The flatness-based control with only one control loop is suggested for improving the dynamic performance of the flatness-based control, especially for high-speed and low-inertia systems. This method, however, lacks current protection. This paper introduces a novel trajectory planning approach for the one-loop flatness-based control of PMSM drives. The focus is on addressing controller limits, an aspect that has received limited attention thus far. The proposed approach ensures control stability by considering the constraints of the maximum motor current (determined by the electrical specifications of the motor and driver) and the switching voltages, which depend on the DC-bus voltage. The method’s effectiveness is validated through simulation studies and experimental tests.

This paper presents a control technique for a boost converter that is connected to a power source via an LC input filter in a continuous conduction mode. The proposed method employs the Lyapunov stability criterion to determine the switching command that guarantees system stability. An estimator is introduced to track the load resistance and losses of the system in real-time. Our control strategy regulates all state variables of the system and additional state variables in the estimator concurrently. Additionally, the start-up transient response is considered in the control algorithm. Finally, experimental results are provided to validate the effectiveness of the proposed control method.

The main objective in microgrids is keeping their frequency and voltage close to the rated values, and ensuring a precise power sharing of their distributed generators (DGs). This can be challenging in a meshed microgrid due to the tight coupling between active and reactive power resulting from its various power line impedances. Centralized control strategies are widely used to address these issues. But, the increase in DGs number in meshed microgrids rises the communication system cost due to the high number of data to be acquired and processed. Most of existing distributed control strategies in literature are unable to treat simultaneously power sharing as well as voltage and frequency restoration. In this paper a distributed consensus-based control is proposed for accurate active and reactive power sharing as well as frequency and voltage restoration in meshed reconfigurable islanded microgrids. The controllers for primary and secondary control are locally adjusted and do not require knowledge of the microgrid structure. The efficiency of the proposed strategies is verified with large load variations, microgrid topology change and various communication delays by simulation and validated by real-time Hardware in The Loop tests.

Parallel operation of multiple AC/DC inverters is favorable in hybrid AC/DC microgrids to avert consecutive conversion stages and increase the system’s efficacy. Yet, several emerging technical challenges impede the expansion of such layout such as the circulating currents, sensitiveness to the input voltage disturbances, load variations and complexity of the control structures caused by using several required measurements. This paper proposes a one-loop sensorless controller which is based on the flatness technique for a non-isolated power supply consisting of n-parallel inverters. The proposed control scheme primarily relies on employing a nonlinear online observer to estimate the line inductor currents and the dc link voltage via information from the input voltage, output voltage, and load conditions to avoid using excessive sensors. In this way, the system reliability is improved by reducing burdens of the communication delays and/or the failures, signal noise, thus the system is featured by simple control. Besides, the system entire losses are modeled by equivalent voltage sources and one current source which implicitly represent all types of the losses by using an online nonlinear estimator for the control purposes. The proposed controller not only has high dynamic performance, wide-bandwidth, low voltage THD but also robust to the abrupt variations in the load and the input voltage. To validate the applicability of the proposed control method and the observer, both simulations and experimental investigations are performed for two paralleled three-phase inverters setup. The obtained results assure the effectiveness of the proposed control method in regulating the output voltage of the parallel DC/AC inverters with fewer number of the sensors against the fluctuations of the input dc voltage and the load perturbations.

The share of electrical energy from renewable sources has increased considerably in recent years in an attempt to reduce greenhouse gas emissions. To mitigate the uncertainties of these sources and to balance energy production with consumption, an energy storage system (ESS) based on water electrolysis to produce hydrogen is studied. It can be applied to AC microgrids, where several renewable energy sources and several loads may be connected, which is the focus of the study. When excess electricity production is converted into hydrogen via water electrolysis, low DC voltages and high currents are applied, which needs specific power converters. The use of a three-phase, buck-type current source converter, in a single conversion stage, allows for an adjustable DC voltage to be obtained at the terminals of the electrolyzer from a three-phase AC microgrid. The voltage control is preferred to the current control in order to improve the durability of the system. The classical control of the buck-type rectifier is generally done using two loops that correspond only to the control of its output variables. The lack of control of the input variables may generate oscillations of the grid current. Our contribution in this article is to propose a new control for the buck-type rectifier that controls both the input and output variables of the converter to avoid these grid current oscillations, without the use of active damping methods. The suggested control method is based on an approach using the flatness properties of differential systems: it ensures the large-signal stability of the converter. The proposed control shows better results than the classical control, especially in oscillation mitigation and dynamic performances with respect to the rejection of disturbances caused by a load step.

DC microgrid applications include electric vehicle systems, shipboard power systems, and More Electric Aircraft (MEA), which produce power at a low voltage level. Rapid developments in hydrogen fuel cell (FC) energy have extended the applications of multi-phase parallel interleaved step-up converters in stabilizing DC bus voltage. The cascade architecture of power converters in DC microgrids may lead to large oscillation and even risks of instability given that the load converters considered as loads feature constant power load (CPL) characteristics. In this article, the output DC bus voltage stabilization and the current sharing of a multi-phase parallel interleaved FC boost converter is presented. The extended Port-Hamiltonian (pH) form has been proposed with the robust controller by adding an integrator action based on the Lyapunov−Energy function, named “Adaptive Hamiltonian PI controller”. The stability and robustness of the designed controller have been estimated by using Mathematica and Matlab/Simulink environments and successfully authenticated by performing experimental results in the laboratory. The results have been obtained using a 2.5 kW prototype FC converter (by two-phase parallel interleaved boost converters) with a dSPACE MicroLabBox platform. The FC main source system is based on a fuel reformer engine that transforms fuel methanol and water into hydrogen gas H2 to a polymer electrolyte membrane FC stack (50 V, 2.5 kW).

This article is focused on an original control approach applied to a transportation system that includes a polymer electrolyte membrane fuel cell (PEMFC) as the main energy source and supercapacitors (SC) as the energy storage backup. To interface the SC with the DC bus of the embedded network, a two-port bidirectional DC-DC converter was used. To control the system and ensure its stability, a reduced-order mathematical model of the network was developed through a nonlinear control approach employing a differential flatness algorithm, which is an attractive and efficient solution to make the system stable by overcoming the dynamic issues generally met in the power electronics networks of transportation systems. The design and tuning of the system control were not linked with the equilibrium point at which the interactions between the PEMFC main source, the SC energy storage device, and the loads are taken into consideration by the proposed control law. Besides this, high dynamics in the load power rejection were accomplished, which is the main contribution of this article. To verify the effectiveness of the developed control law, a small-scale experimental test rig was realized in the laboratory and the control laws were implemented in a dSPACE 1103 controller board. The experimental tests were performed with a 1 kW PEMFC source and a 250 F 32 V SC module as an energy storage backup. Lastly, the performances of the proposed control strategy were validated based on real experimental results measured during driving cycles, including motoring mode, ride-though, and regenerative braking mode.

To deal with the intermittency of renewable energy resources, hydrogen as an energy carrier is a good solution. The Polymer Electrolyte Membrane Fuel Cell (PEMFC) as a device that can directly convert hydrogen energy to electricity is an important part of this solution. However, durability and cost are two hurdles that must be overcome to enable the mass deployment of the technology. In this paper, a management system is proposed for the fuel cells that can cope with the durability issue by a suitable distribution of electrical power between cell groups. The proposed power electronics architecture is studied in this paper. A dynamical average model is developed for the proposed system. The validation of the model is verified by simulation and experimental results. Then, this model is used to prove the stability and robustness of the control method. Finally, the energy management system is assessed experimentally in three different conditions. The experimental results validate the effectiveness of the proposed topology for developing a management system with which the instability of cells can be confronted. The experimental results verify that the system can supply the load profile even during the degradation mode of one stack and while trying to cure it.