Robust and secure microgrid (MG) design requires test configurations that accurately reflect real-world systems and comply with established standards. This paper reviews guidelines for military MG design, focusing on standards issued by United States defense and security organizations. It also evaluates widely recognized IEEE and CIGRE test MG configurations for their ability to replicate military power network characteristics. To assess analytical accuracy, power flow studies are performed on a selected test MG using DIgSILENT PowerFactory, ETAP, and OpenDSS. A comparative analysis of results highlights differences in modelling approaches and computational precision among these tools. The findings provide insights into the suitability of existing test configurations and simulation platforms for military MG research, supporting the development of secure, standardcompliant solutions.

This paper presents a robust discrete-time sliding mode controller (DT–SMC) for a bidirectional DC/DC converter that is used as an energy storage interface in DC microgrids. The proposed controller is implemented in a hierarchical cascaded control structure comprising an inner current loop and an outer voltage loop, together with a current-reference limiter and duty-cycle saturation. Both loops adopt DT–SMC to achieve fast sampled-data tracking under nominal non-saturated operation. A multirate framework is implemented to balance dynamic performance, control accuracy, and computational complexity. To improve disturbance rejection, disturbance estimators (DEs) based on the sliding variable are incorporated in both loops and equipped with an anti-windup compensation to suppress error accumulation. The controller requires only the converter current and terminal voltages, facilitating practical digital implementation with fixed-frequency pulse-width modulation (PWM). Simulation results compare the proposed method with benchmark cascaded DT–PI and STA–SMC controllers, while experimental tests on a laboratory prototype confirm its practical feasibility. The presented results indicate chattering mitigation through reduced duty-cycle variation, accurate reference tracking, fast transient response, and disturbance rejection under the tested operating conditions.

Under fluctuating demand and distributed generation, smart-grid (SG) modernization depends on the reliability and efficiency of power electronic converters (PECs). However, PECs face operational stresses and gradual degradation, which compromise their performance. To address these challenges, digital twin (DT) technology is introduced as a virtual counterpart that interacts with the physical PEC, enabling real-time monitoring, predictive maintenance, and performance optimization. Numerous DT implementations for PECs have been reported, yet most focus on modeling/control, leaving communication requirements and technology selection underexplored. To address this gap, in this paper we first review existing DT realizations to identify their key communication requirements. Based on that research, we proposed a classification framework that links DT functionality to appropriate communication solutions and provided practical guidance for selecting the optimal technologies. These guidelines specify which communication technologies are most suitable for each DT category, which makes informed decision-making easier when DT-enabled PECs are used in modern smart grids.

This paper presents the control of DC-DC buck converter. The control strategy is based on the theory of discrete-time sliding mode control to ensure robustness against parameter variations and external disturbances. The output voltage regulation is achieved using a digital controller that combines discrete-time first-order sliding mode control with a discrete-time realization of the super-twisting algorithm, commonly used in second-order sliding mode control. The design of the proposed controller is performed using a discrete-time model of the DC-DC buck converter. Extensive simulations were conducted in Matlab/Simulink to validate the performance of the control algorithm under varying load conditions and input voltage fluctuations. A comparative study between conventional PI controller and the proposed discrete-sliding mode based controller in tracking of various voltage references under action of disturbances is given.

This paper presents a comparative evaluation of two Four Diode Model (FDM) variants for photovoltaic (PV) I–V (current-voltage) curve generation with the goal of efficient Maximum Power Point (MPP) extraction in inverter control systems. The models considered include the exact FDM and an approximate solution based on the Lambert W function. The study focuses on assessing the trade-offs between computational time and accuracy during real-time curve generation. Equilibrium optimizer (EO) algorithm, along with its hybrid variants, is applied to each model to generate the I–V curve, from which the MPP is identified directly. Performance metrics include execution time and curve fidelity, providing insights into the suitability of each model for secure and efficient MPPT implementation in mobile microgrid inverters.

Reliable and computationally efficient modeling of photovoltaic (PV) cells is essential for real-time control of power electronic systems, especially in safety-critical applications such as inverter control in smart grids and defense-related infrastructures. This paper investigates the accuracy, speed, and robustness of several PV cell models — including the Single Diode Model (SDM), Double Diode Model (DDM), and Triple Diode Model (TDM) — using closed-form and semi-analytical parameter estimation techniques based on the Lambert W function. The performance of each model is evaluated with respect to estimation time, curve-fitting accuracy, and its impact on Maximum Power Point Tracking (MPPT) behavior. The results demonstrate that, while more complex models offer higher fidelity, the computational burden may compromise real-time applicability.

This paper presents a robust voltage control of a buck converter with inductor current limitation applying discrete-time sliding mode control. The proposed voltage controller is designed in a hierarchical cascade structure comprising an inner current loop with current limiting and an outer voltage loop. Both loops employ sliding mode control in discrete time because of the achievement of finite-time dynamic performance. To ensure robustness against matched external and parametric disturbances, a disturbance estimation is introduced based on the integral of the sliding variable combined by an anti-windup mechanism to suppress overshoots. Including the current limiter ensures that the inductor current remains within safe operational boundaries, even during transient conditions, preventing hardware stress and enhancing reliability. The controller is implemented using pulse-width modulation (PWM) ensuring a fixed switching frequency and ease of practical implementation. The simulation results validate the proposed approach, demonstrating high performance, strong disturbance rejection, and negligible overshoot, while maintaining a straightforward and efficient control design.

This paper presents the development and validation of a computation model of a cascaded multilevel power inverter as an initial step toward creating a high-fidelity digital twin. A preliminary overview of the cascaded multilevel inverter topology is provided, followed by introducing a mathematical modeling approach that uses graph theory to derive the system's nodal equations. The computation model is implemented in a programmable environment, and its output is compared to the MATALB/Simulink-based simulation, which serves as a reference for performance evaluation. The evaluation is performed using the mean square error (MSE) metric to quantify the accuracy of the proposed model. Results indicate a close agreement between the computation model and simulation data, confirming the model's potential for integration into future real-time digital twin architectures for power converter control and diagnostics.

This paper presents a discrete-time sliding mode voltage controller for a DC-DC boost converter. A disturbance estimator is integrated into the controller, ensuring a fast dynamic response and robustness against matched disturbances and parametric uncertainties, such as input voltage fluctuations, load variations and internal nonlinear dynamics that affect system performance. The disturbance estimator improves the rejection of unmeasured perturbations using only local measurements, without requiring additional sensors or complex adaptive structures. A cascade control scheme is adopted, with an inner inductor current loop and an outer voltage regulation loop. Both controllers utilize disturbance-compensated discrete-time sliding mode control strategies. The simulation results validate the effectiveness of the method, comparing it to the optimized discrete-time proportional integral (DT PI) cascade controller, demonstrating precise voltage regulation and tight performance under disturbances.

The rapid increase in electricity demand and peak load consumption has led to rising energy costs and grid instability. This paper proposes an adaptive control strategy for peak shaving, integrating energy storage (ES) and electric vehicles (EV) with real-time power supply-demand monitoring. The proposed system dynamically estimates household demand, including EVs as a load, and adjusts ES and EV charging and discharging schedules based on energy availability, load conditions, and time-of-use (TOU) pricing. By leveraging photovoltaic (PV) generation, surplus energy is stored in the ES and EV during low-demand periods and discharged during peak-demand hours, thereby reducing grid dependency and electricity costs. A real-time simulation model is developed to validate the effectiveness of the proposed strategy. The results demonstrate significant improvements in load balancing, cost reduction, and peak-shaving efficiency, ensuring optimal utilization of renewable energy sources and storage assets.

The widespread deployment of photovoltaic (PV) systems in urban areas poses new challenges for integration into the low-voltage grid, operation under variable meteorological conditions, and the impact of local disturbances. Research using Hardware-in-the-Loop (HIL) simulations, especially techniques with physically present controllers (Controller Hardware-in-the Loop - C-HIL), represents a powerful environment for testing and validating power electronics-based converter control strategies in real-world conditions without the risks and costs associated with field experiments. This paper presents the application of C-HIL simulation to analyze and optimize the operation of a home PV system integrated into an urban distribution grid. The conducted case studies address operational scenarios such as rapid changes in solar radiation, load fluctuations, and voltage disturbances, demonstrating the effectiveness of the C-HIL platform for assessing dynamic performance, voltage quality, and stability. The results confirm that C-HIL simulation can provide useful insights for the design of PV systems aimed at the safe and widespread deployment of distributed renewable energy sources in urban networks.

U radu se upoređuju tri metode za estimaciju i kompenzaciju poremećaja u diskretnim sistemima sa kliznim režimom (KR). Prva metoda koristi Luenbergerov opserver poremećaja, druga - nominalni model upravljanog objekta, a treća - integral signala klizne funkcije. Cilj rada je da pokaže ekvivalentnost navedenih metoda u primeni na diskretne sisteme upravljanja sa KR u nominalnim uslovima na jednostavnom sistemu upravljanja objektom prvog reda tipa čistog integratora. Poseban doprinos rada je modifikovani estimator poremećaja koji kombinuje Luenbergerov estimator sa estimatorom na osnovu integrala klizne funkcije. Teorijski rezultati su ilustrovani simulacionim eksperimentima.

The building integrated photovoltaic (BIPV) systems are a popular option for integrating renewable energy sources in the power system, and for users to reduce energy bills. This paper analyzes the performance of inverters in BIPV systems with oversized PV configurations. Oversizing PV systems has become a common practice to optimize energy production, particularly in periods of low sunlight, but it raises concerns about efficiency, power quality, and potential economic implications. Performance analysis is performed on two inverters, one operating under an overloaded regime due to the oversized PV installation and another under normal conditions. Several performance metrics are compared, including efficiency, thermal behavior, THD, and economic factors. The results demonstrate that although oversizing can slightly increase the inverter’s temperature and affect power quality, the efficiency was better for the overloaded inverter, although the investment costs have increased. These results offer practical insights for designing PV systems, showing that oversizing can be beneficial if properly managed.