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The integration of Renewable Energy Resources (RERs) into electrical grids introduces significant challenges concerning the reliability and stability of the grid. This paper focuses on these challenges, particularly the issues of real-time load forecasting and adaptive inertia control in renewable integrated grids. A data-driven, deep learning-based approach is proposed to dynamically forecast real-time load and renewable energy generation, using the New England IEEE 39-Bus Power System as a case study. To enhance the dynamic performance of the microgrid, the paper introduces an enhanced fractional extended state observer-based linear active disturbance rejection control mechanism coupled with a feedback architecture. This control scheme aims to provide adaptive inertia to the system, thus improving its ability to handle fluctuations and intermittencies inherent in RERs. The effectiveness of the proposed controller is rigorously compared with existing approaches through simulation studies, validating its superior performance for the IEEE 39-Bus Power System under examination. To further substantiate the findings, a hardware-in-loop real-time experimental analysis is conducted using OPAL-RT hardware. This hardware-based analysis serves as a functional validation of the proposed data-driven forecasting algorithm confirming its viability to improve the grid reliability.

The increasing adoption of renewable energy sources (RES), such as solar photovoltaics and wind turbines, is transforming electricity generation. However, integrating RES within DC microgrids (DCM) for applications such as fast DC charging in electric vehicles (EVs) presents challenges, including low inertia, power fluctuations, and voltage instability. This study addresses these challenges with novel control strategies and optimization algorithms. A hybrid Firefly Algorithm-Particle Swarm Optimization (FA-PSO) approach is used to tune Takagi-Sugeno Fuzzy Inference Systems (TSFIS), Adaptive Neuro-Fuzzy Inference Systems (ANFIS), and Fractional Order Proportional-Integral-Derivative (FO-PID) controllers. This strategy optimizes power management within the DCM, ensuring faster convergence, superior accuracy, and reduced topological constraints. In addition, a comprehensive Small Signal Stability Analysis (SSSA) evaluates the impact of the proposed hybrid optimization techniques on DC microgrid stability. Crucially, a hardware prototype validates these strategies under real-world uncertainties, such as varying wind speed and solar insolation, demonstrating their effectiveness and feasibility for practical DC microgrid applications with integrated EV charging.

Active switched inductor (ASL) dc–dc converters have very high step-up voltage gain but practically they suffer from high voltage stress across switches because of the resonance caused by the mismatch among the inductor values and switch parameters. This article presents a new hybrid dc-dc converter topology derived from ASL and passive switched capacitors (PSC). The proposed topology has high step-up voltage gain over wide range of duty cycle. The resonance due to mismatch of parameters is eliminated. The proposed converter has low voltage stress, low current stress on circuit elements, and common ground between input and output ports. The circuit configuration, operating principle and steady state analysis of the proposed converter are presented. The key performance parameters are compared with that of other high-gain dc–dc converters. A 300 W laboratory prototype is developed and experimental verification is carried out for the voltage step-up from 30 to 400 V. The closed-loop operation is also verified experimentally and results are presented.

Single-phase dual-buck ac–ac (DBAC) converters are gaining attention due to their intrinsic protection from shoot-through and open-circuit problems of conventional ac–ac converters. However, research works on DBAC converters are mainly concentrated around unipolar topologies. In a few developed bipolar topologies to date, the inverting buck–boost operations (for series voltage injection and step-variable frequency outputs) are inefficient and burdened by large voltage and current stresses (${v}_{\text{in}} + {v}_o\ \text{and}\ {i}_{\text{in}} + {i}_o$) of switching devices and ripples of passive elements. In this article, an efficient dual-buck structured buck–boost ac–ac converter is proposed, with the following features: no voltage source shoot-through and inductor open-circuit problems, natural attainment of safe commutation without additional protection circuitry or complex control, no need for pulsewidth modulation dead times, and elimination of high-frequency conduction of mosfet’s body diodes and related slow reverse recovery issues. The proposed converter provides distinct types of efficient inverting and noninverting buck and boost operations, with smaller switch voltage/current stresses (${v}_{\text{in}}/{v}_o$ and $\ {i}_{\text{in}}/{i}_o$) and passive component ripples. Combined inverting and noninverting buck–boost operations are also proposed with separate tuning of buck and boost voltage transfer ratios. A simple adaptable switching strategy provides the switch control pulses for all circuit operations by modulating the buck and boost control reference signals. The proposed converter provides sustained input/output currents and performs well with nonresistive loads. Extensive theoretical analysis is presented followed by practical verifications on a 400-VA laboratory circuit.

Induction motor powertrains are emerging as a cost-effective option for high-power electric vehicles (EVs). A differential four-wheel drive (D4WD) EV based on two open-end winding induction motor (OEWIM) propulsion is presented in this article. Each OEWIM is driven by two two-level voltage source inverters (VSIs) with two isolated battery packs as the source. The proposed drive control algorithm integrates the uniform state-of-charge (SoC) distribution and fault-tolerant operation. A two-stage lookup table (LUT)-based direct torque control (DTC) scheme is proposed to balance the SoC of batteries by selecting the suitable redundant VSI voltage vectors. The proposed LUT-DTC scheme is less sensitive to variations in motor parameters and provides excellent steady-state and transient performance. The results show the superiority of the proposed controller in terms of battery SoC balancing. The performance of the EV drive with the proposed LUT-DTC is validated by both simulation and laboratory experiments for the FTP75 and HFET driving cycles under different operating modes under normal and fault conditions. The dual-motor-driven D4WD with the proposed LUT-DTC is found to achieve 89.2% efficiency.

Time-delay is an inevitable operator causing slow dynamic response of related systems employing harmonic sequence (HS) filters/extractors. This letter presents a new concept of flexible time-delay designs as a further generalization of two-sample methods (i.e., delayed signal cancellation) to improve the dynamic response and robustness of HS filters/extractors. The new concept offers flexible designs of filters/extractors to improve both the steady-state quality and dynamic response of filter/extraction stages. Comparative experimental results show significant improvements in filtering performance regarding fast dynamic response, small steady-state errors, improved robustness, and flexible designs to filter implicit harmonic sidebands. These feasibilities are especially beneficial for applications in power systems and power electronics with the available information on harmonic sidebands.

This article proposes a new multiobjective predictive control approach and an optimized switching scheme to precisely regulate the dc-voltages in bipolar dc-grid-based charging stations working under critical conditions. An angular region is preselected to reduce the size of control sets to seven candidates within minimized angle error of 30°. Then, two subregions are located to further simplify finite sets without losing options for multiobjective optimization. Lastly, a hybrid switching scheme is proposed to improve current regulation working under a reduced sampling frequency. Delayed-signal-cancellation technique and instantaneous power theory are also employed to ensure a resilient operation under grid-voltage distortions. Consequently, the proposed control strategy can precisely balance dc-voltages, track voltage references, and regulate grid-injected currents against unbalanced dc-loads and ac-grid distortions. MATLAB/Simulink and an experimental prototype are utilized to investigate the comparative performances between the proposed approach and the recent predictive control methods. The simulation and experiments show significant improvements in dc-link voltages including reference tracking, dc-voltage balance, fast dynamic response, and harmonic reduction of ac-currents under a reduced sampling frequency.

The demand for motor drives based on multiphase machines (MMs) is increasing due to their inherent fault-tolerant capabilities. To achieve satisfactory post-fault operation, a proper fault-tolerant controller is needed. Some direct-torque-control (DTC) techniques have been reported for five-phase induction motor (FPIM) drives under an open-phase fault (OPF). DTC offers simplicity, fast response, and less parameter sensitivity. However, the existing fault-tolerant DTC methods were designed for two-level voltage-source inverters (VSIs). A three-level neutral-point-clamped (NPC) VSI allows greater flexibility in the switching states, lower current and torque ripple, and reduced common-mode voltage (CMV). However, the increased number of switching states requires the design of new DTC methods, able to tolerate OPFs while providing satisfactory performance in various aspects. In this article, two fault-tolerant DTC techniques are developed for three-level NPC VSI-fed FPIM drives under an OPF. The possible switching states are synthesized with suitable virtual vectors (VVs), addressing the dc-link voltage balance, ${\text {d}v/\text {d}t}$ , CMV, and dc-link utilization. The two methods are compared under an OPF in these terms, as well as regarding the average switching frequency. Comparative experimental results are provided to assess the viability of the developed DTC schemes at steady-state and dynamic conditions.

Only precise industrial applications can benefit from the high-frequency performance of variable-speed drives with low switching losses. A five-phase induction motor (FPIM) is connected to a voltage source inverter (VSI) via a $LC$ filter (low pass filter) to reduce high-frequency losses in the motor. A five-phase sinusoidal voltage is used to lower the high $dv/dt$ at the motor terminals. However, sustained resonant frequency oscillations destabilize closed-loop control of the FPIM drive at certain operational points. This paper presents and analyzes a variety of high-frequency SVPWM techniques, both continuous and discontinuous. It is also possible to optimize the switching frequency of the five-phase two-level VSI fed FPIM drive using an improved current ripple prediction method. Auxiliary circuits and high-frequency sensors are not necessary in this system, making it more stable. Simulated and experimental results are used to evaluate the stability of a drive under a variety of conditions.