Shaik Mohammad Irshad

The abstract should briefly state the review methodology, including databases, publication period, source-selection criteria, and number of studies reviewed. The statement presenting 5% as an IEEE 519 current-THD limit should also be correct...

Doubly Fed Induction Generators (DFIGs) have been frequently controlled through Direct Field-Oriented Control (DFOC) in Wind Energy Conversion Systems due to their ability to independently regulate both active and reactive power, but their performance critically depends on the tuning of PI controller parameters. Manually tuned PI controllers often lead to degraded power quality under varying conditions. To address this challenge, this paper proposes two intelligent control approaches, DFOC-GA-PI and DFOC-PSO-PI, incorporating Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), respectively, to tune DFOC’s power controller. The suggested approaches adjust controllers by utilizing a multi-objective fitness function that considers multiple performance metrics. Comprehensive Matlab/Simulink simulations were performed under realistic conditions to demonstrate that DFOC-GA-PI notably outperforms traditional DFOC (DFOC-C-PI), delivering a 46% enhancement in active power fluctuation, 57% enhancement in THD, and 25% faster response time. DFOC-PSO-PI achieves faster convergence compared to DFOC-GA-PI; however, it exhibits slightly lower performance. The robustness assessment under realistic varying wind and DFIG parameters proves the resilience of DFOC-GA-PI frameworks against parameter variations. Comparative examinations under three different scenarios, including nominal, moderate, and the most challenging conditions, demonstrate the superiority of both proposed DFOCs in improving power quality, THD of current, and overall performance, ensuring excellent grid compliance. Depending on the populations/particles size and generations/iterations, the developed DFOC frameworks exhibit moderate computational complexity, and convergence is achieved within approximately 4 seconds on a standard PC (intel i7/ 16 RAM), which can be reduced to a few microseconds on modern calculators or high-performance controllers, confirming the practical feasibility of these developed frameworks.

The regular fault detection approaches are failed to detect the faults in wind integrated transmission networks due to intermittency nature of the wind energy. More reliable schemes are required to accomplish the detection of faults in presence wind. This article proposed empirical mode decomposition (EMD) based fault detection scheme to detect various faults in wind integrated transmission lines during the normal and stressed conditions of the system. The instantaneous current measurements available at either sending or receiving end are processed through EMD to decompose it into a series of intrinsic mode functions (IMFs) and IMF2 is identified as a dominated IMF with numerous case wise investigations. 1/4th cycle moving window is used to calculate the absolute sum of the IMF2 coefficients to detect the faults with the support of a predefined threshold. The efficacy of the method is tested on different types of faults during the normal condition in presence of wind and later extended to stressed conditions such as power swing. The method is reliable during the typical cases and includes remote end and high resistance faults. All the experiments are carried out in Simulink to generate the measurement data and programs are executed in MATLAB.

The integration of photovoltaic (PV) systems with hydrogen production offers a sustainable method to utilize solar energy for the manufacturing of clean fuel. This paper examines recent breakthroughs in the integration of photovoltaic technology with water electrolysis, highlighting the technical feasibility and economic viability of these systems. Principal hydrogen production technologies, such as alkaline, proton exchange membrane (PEM), and solid oxide electrolyzers, are assessed regarding their compatibility with photovoltaic power outputs. Direct coupling solutions, including photovoltaic-electrochemical (PV-EC) systems, are emphasized for their capacity to optimize energy conversion processes. Notwithstanding the potential, obstacles such as the variability of solar irradiation, the responsive behavior of electrolyzers to changing power inputs, and the necessity for effective energy management systems remain. Recent research has illustrated kilowatt-scale solar hydrogen generation systems, with demonstrated production rates of up to 0.5–1.2 Nm³/h under peak irradiance, and overall solar-to-hydrogen efficiencies reaching 10˘18%. Levelized cost of hydrogen (LCOH) values from PV-powered systems currently range from 4 to 8 USD/kg H₂ , depending on the technology and location. Advancements in power electronics, particularly maximum power point tracking (MPPT) techniques, are essential for enhancing the efficiency of photovoltaic-powered electrolysis. The novelty of this study lies in its comprehensive and current synthesis of PV-electrolysis integration techniques, with a specific emphasis on direct coupling configurations, system scalability, and the enhancement of energy management through advanced MPPT techniques.It is essential to tackle these issues with creative system designs and control methodologies to facilitate the wider deployment of PV-hydrogen systems, thereby considerably aiding global decarbonization efforts.

The increasing integration of parallel grid-forming (GFM) inverters within islanded AC microgrids introduces significant challenges in maintaining robust voltage regulation and accurate power sharing. Central to controlling the output voltage is the need for a reference voltage, which can be derived using the virtual synchronous generator (VSG) concept. The VSG not only ensures active power sharing but furthermore provides inertia emulation, reducing the rate of change of frequency (ROCOF) in response to sudden load variations, thereby enhancing system stability and frequency support. To achieve precise voltage regulation, a model predictive control (MPC) strategy is commonly employed, particularly the finite control set-MPC (FCS-MPC). However, FCS-MPC relies on an accurate system model, which can limit performance under parameter mismatches or dynamic changes. To overcome this limitation, this paper proposes a modified model-free predictive control (MFPC) based on the dual second-order generalized integrator-quadrature signal generator (DSOGI-QSG) strategy. The MFPC eliminates the need for an explicit system model by using an ultra-local model (ULM) for prediction, with the unknown function in the ULM playing a critical role in the accuracy of output voltage prediction. Algebraic identification methods are typically used to estimate this unknown function. Nevertheless, as the sampling time increases, the estimation becomes increasingly distorted, leading to prediction inaccuracies. The DSOGI-QSG is introduced to extract a filtered version of the unknown function, improving the quality of the estimation and, consequently, the prediction accuracy. Simulation results using MATLAB Simulink demonstrate the effectiveness of the proposed method, showing enhanced robustness, improved dynamic response, and reduced harmonic distortion compared to conventional MFPC.

Power transformers are the most important component in power system. Exposing these transformers to the harmonic distortions causes additional heat losses, insulation stress, decrease in lifetime of insulation, and reduced power factor with decrease in efficiency of the system. The lifespan of distribution transformers is influenced by the fragility of power quality in power networks. Harmonic mitigation filters with robust control technique are required to reduce the harmonic effects on power transformer. Traditionally, synchronous reference frame (DQ) is employed to control the shunt active power filter (APF) for mitigation of harmonics in power transformers. DQ control of Shunt APF lacks merits of fast response, delayed operation due to phased lock loop under abnormal grid conditions leading to insufficient harmonic elimination. A developed DQ method based on detecting the positive and negative sequence components is proposed to precisely control the shunt APF for reliable operation of power transformer. This detection technique improves the response time, mitigate the harmonics effecting the operation of transformer and overall power factor. The proposed control system is evaluated under different abnormal operating scenarios and compared with traditional DQ method. The results and analysis confirm the efficacy of the developed DQ method in improving the power transformer performance.

Power quality issues have become widespread due to nonlinear electronic converters and loads. Nonlinear components in the power system hamper the power quality, network efficiency and voltage regulation. The power quality issues like sag, swell, and voltage unbalance can be reduced by employing a dynamic voltage restorer (DVR). DVR provides the compensating power from a DC source to minimize the effect of sag, swell, and voltage unbalance. This article presents a power system with DVR using a photovoltaic system (PV) as a DC source instead of a conventional battery source. This article proposes a modified instantaneous power (PQ) control technique to generate the reference signal of load voltage to assure the DVR's superior performance. This modified technique uses an anti-aliasing filter to generate a reference signal. This proposed technique is tested under extreme power quality issues of 80% sag, 20% sag, 120% swell, 170% swell, and voltage unbalance. The DVR is modeled and simulated using MATLAB/Simulink. A comparison is made between the traditional and modified PQ methods from the obtained results. The analyzed results under severe power quality issues suggest that the proposed P-Q control technique is a preferable option for the DVR with PV as a DC power supply.

This article presents an overview of the technical and financial feasibility analysis of integrating a photovoltaic (PV) source with the conventional power system to supply the auxiliary load at the Al Suwairah 33/11 kV primary substation (PSS) in Suhar, Sultanate of Oman. This study estimates the required electrical energy for the primary substation's auxiliary load. A method is implemented to utilize the available area in the primary substation for determining the solar photovoltaic system's capacity. PVSyst software is employed to determine the ideal system capacity. The proposed solar PV system's payback period and overall annual savings have been evaluated using a series of simulated analyses. The proposed PV can inject 172.5 MWh/year with an average performance ratio of 0.826. The economic evaluation by the photovoltaic system (PVSyst) considering the present auxiliary load at the Al Suwarah PSS has suggested a total payback period of 8.9 years which is quite feasible. The cost of power generated by the proposed system is 49.2% less than the cost of power supplied from the utility service provider.

Due to uncertain photovoltaic (PV) power generation, analyzing the voltage stability of transmission networks with a large PV plant is challenging. The stability of PV output power is a critical factor in establishing PV penetration levels in active transmission networks when assessing loading capabilities. Therefore, this article contributes to enhancing the understanding of how a static synchronous compensator (STATCOM) could be used as part of the power system network. STATCOMs are often used to improve the static and transient voltage, maintain transmission limits, and reduce low-frequency disturbances. With the help of a STATCOM unit, a proper investigation and analysis of dynamic voltage stability in a transmission system are presented. The validity of the study is evaluated by the Saudi Arabia grid code (SAGC). The system being tested is comprised of a 300 MW PV plant in Sakaka, Saudi Arabia, integrated into a 17-bus transmission power network and a STATCOM, which is employed at one of the buses. PSAT software is used to evaluate a number of case studies to determine the transient voltage stability with and without the STATCOM and the PV plant. The simulation findings demonstrate how STATCOM functions to improve the quality of the power system in accordance with the SAGC. In addition, the analysis of voltage stability demonstrates that the power network’s resilience to short circuits at the PV system’s grid connection point significantly impacts the voltage’s dynamic behavior.