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The integration of the renewable energy sources (RESs) into the power grid, drives a significant transformation in the conventional power generation landscape. This transition from traditional synchronous generators to inverter based RESs introduces unique challenges in maintaining the grid frequency stability due to the reduced system inertia. The inherent stochastic nature of the RES power generation, load demand, and grid inertia includes further complexity in the assessment of frequency stability. Existing studies have limitations, including neglecting the stochastic nature of RES generation and load demand fluctuations, relying on limited metrics, and lacking a comprehensive day‐to‐day assessment. To address these shortcomings of the existing approaches, this paper introduces a novel methodology for assessing frequency stability in power grids with high RES penetration. It proposes three indices for evaluating grid frequency sensitivity, resiliency, and permissibility amidst varying RES integration. Utilizing a stochastic approach, the study incorporates uncertainties in RES generation and load demand, offering a comprehensive framework for day‐to‐day frequency stability analysis. Additionally, it presents a systematic method to ascertain the necessary inertial support for maintaining desired frequency reliability in RES‐dominated grids. The effectiveness of these methodologies is validated through a case study on a modified IEEE 39‐bus test system, demonstrating their applicability in ensuring reliable grid operation under high RES scenarios. [ABSTRACT FROM AUTHOR]

In this paper, a terminal sliding mode backstepping controller (TSMBC) has been proposed for various components of a hybrid AC/DC microgrid (HADMG) to enhance its dynamic stability. The proposed control technique is employed to generate switching control signals for converters, which serve as the primary interface between the DC bus and the AC bus in a hybrid microgrid. Additionally, this technique facilitates the interface of PMSG-based wind generators, solar photovoltaic generators, and battery energy storage systems with the DC bus. Through the implementation of the composite control technique, the global stability of the microgrid is ensured by driving all the states of the HADMG associated with various components to converge towards their intended values. Afterward, the Lyapunov control theory has been used to analyze the converter and inverter's large-signal stability while ensuring the robustness of the proposed robust composite controller. Finally, an extensive simulation study was conducted on a hybrid microgrid to verify the efficacy of the designed controller in maintaining power balance amidst variations in the system's operational regimes. Moreover, the effectiveness of the controller's practical implementation is confirmed by real-time processor-in-the-loop analysis. Simulation results clearly show that the proposed TSMBC improves the overall dynamic performance of the hybrid microgrid with less overshoot (0%) and settling time (110 ms) in DC bus voltage when compared to the existing sliding mode controller. • Enhance the dynamic and transient stability of an AC/DC hybrid microgrid (ADHMG). • A composite terminal sliding mode backstepping controller (TSMBC) is used to obtain the switching control signals for the converters and inverters. • Maintain the power balance with changes in the system's operating point. • It provides superior performance as compared to the existing control approach in terms of overshoot and settling time. [ABSTRACT FROM AUTHOR]

In this study, the energy data transfer problem in a DC microgrid with multiple renewable powered base stations (BSs) is considered. These BSs can share the renewable generation among each other. The energy cooperation is optimised by the control unit. For effective energy cooperation, energy data needs to be transferred from BSs to the control unit with low latency and high reliability. For cellular enabled microgrid communication, the energy data exchange and cellular communication both use the same communication resources. Thus, there will be interference at the control unit and cellular user (CU), which degrades the reliability of energy data transfer. To solve this problem, a linear precoding technique is designed to minimise the mean square error of the desired messages at the control unit, BSs, and CU while the interferences are kept at a predefined level. For the designed precoders, the expressions of signal‐to‐interference‐plus‐noise ratio are formulated and the error performance is analysed. Numerical simulation has been performed to compare the considered precoding technique with other precoding techniques. The simulation results demonstrate that optimum precoding can improve the error performance at the control unit, BSs, and CU by 1, 5, and 3 dB, respectively. [ABSTRACT FROM AUTHOR]

In this work, DC and AC parts of hybrid microgrids are interconnected by a neutral point clamped—NPC converter controlled using a new backstepping predictive (BP) method. The NPC converter is controlled to operate in the DC microgrid voltage control mode or in the AC microgrid power control mode. The novel backstepping predictive controller is designed using the dq state space dynamic model of the NPC converter connected to the hybrid microgrid. The designed BP controller regulates the DC voltage or AC injected power, balances the capacitor voltages, controls the AC currents, and enforces the near unity power factor. Simulation (MATLAB/Simulink) and experimental (laboratory prototype) results show that the converter can regulate the DC voltage in the DC microgrid interconnection point, by adjusting the AC power conversion to compensate variations on the loads or on the distributed renewable energy sources in the DC microgrid. AC currents are sinusoidal with low harmonic distortion. The obtained BP controller is faster at balancing capacitor voltages than PWM (pulse width modulation) control with carrier offset. The fast AC power response allows the converter to be used as a primary frequency regulator of the AC microgrid. This research is appropriate for power and voltage control in hybrid microgrids with renewable energy. [ABSTRACT FROM AUTHOR]