Rajpurohit, Bharat Singh

The smart grid has become an essential infrastructure for the modern power grid as new technology and communication networks are integrated, revolutionizing the energy sector. However, the enhanced interconnectivity and complexity of the smart grid have prompted fear regarding its susceptibility to cyber-attacks. This research paper provides a thorough examination of the difficulties encountered by cyber security in the smart grid and investigates inventive strategies to improve these threats. The research paper explores the complex and varied nature of cyber risks in the smart grid, including advanced attacks on essential infrastructure and possible weaknesses in communication protocols. The implementation of digital technologies, such as Smart Meter (SM), Advanced Metering Infrastructure (AMI), and Internet of Things (IoT), aims to enhance the efficiency, dependability, and sustainability of the system. Lastly, it explores potential advancements and upcoming technologies that show potential to improve the security of the smart grid, including blockchain, artificial intelligence, and quantum-resistant cryptography. A comprehensive analysis of the simulation findings for Load Frequency Control (LFC) has been thoroughly examined.

This paper deals with accurately estimating harmonics/interharmonics in the modern electrical power system. The sources of interharmonics and the problems that are caused by them have also been discussed. This paper uses a cumsum based method for estimating the number of frequency components present in the signal along with estimation of signal parameter based rotational invariance method to obtain the signal attributes. For test and validation purposes, two synthetic signals containing harmonic as well as interharmonic frequency components have been used. Relative rms reconstruction error is calculated to show the accuracy of the estimation. The results have also been compared with the fast Fourier transform based method.

The current state of the art on emerging and efficient techniques for condition monitoring of permanent magnet (PM) alternating-current (AC) machines deployed in electric vehicle (EV) applications is presented. The discussion includes the most common and specific types of faults in PM motors, such as rotor demagnetisation and stator inter-turn faults, respectively. Fault indicators, such as voltage (vs) and current (is) signals and machine signatures based on motor back electromotive force (EMF) (EB) and magnetic flux (ϕ), are taken into account as a measuring quantity in diagnosing motor faults. Other signatures, including thermal analysis, acoustic noise, and vibrations, are also illustrated as some of the emerging techniques in estimating the performance of EV motors while under operations. In addition, various fault modelling methods, condition monitoring techniques, and comprehensive approaches applied in diagnosing the effect of machine faults during its incipient stages are illustrated. Since most of the fault diagnostic techniques discussed here include only machine-based quantities as fault indices/indicators, the provided solutions are therefore found to be more reliable and accurate for diagnosing the motor faults. This comprehensive review study is inclusive of the existing fault diagnostic techniques, which are currently employed in industrial and commercial practices, in addition to the new methodologies proposed by the authors. All the given condition monitoring schemes therefore seem significantly vital in estimating the state of health of PM AC machines while under operation in all-electric transportation systems.

This article presents a novel technique to improve the system response utilizing a sensorless Nonlinear Sliding Mode Observer and a Quadrature Phase-Locked Loop (NLSMO and QPLL) controller. Rather than using a conventional PI controller, a Sliding Mode Controller (SMC) and an Extended State Observer (ESO) are used to compute the speed. Speed controller (PI based) requires fine tuning to operate PMSM drive in all speed ranges, whereas using the SMC + ESO method can compute it, based on some parameters calculated for wide speed ranges. The SMC + ESO approach assimilates the concept of sliding surface function control and the system state variables. The QPLL provides advantage in position estimation which reduces loop filter requirements. The NLSMO + QPLL technique allows synchronization to be achieved and maintained with a lower-order filter. An NLSMO + QPLL helps reducing the increased chattering caused by high switching gain. To counter the chattering problem and improve the estimation accuracy, the method incorporates an anti-disturbance property. To support the theoretical analysis, simulation and experimental results are presented. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.

This study presents an approach for fabricating flexible and stable electroplated circuits directly onto fabric and thread. We achieve this through a simple method. Pencil-drawn patterns on cotton fabric are followed by copper electroplating in a copper sulfate solution. This method eliminates the need for complex pre-treatment and lithography techniques, thus enabling rapid and on-site circuit development. This research investigated the influence of different pencil grades, drawing frequency, and plating time on the overall conductivity and flexibility of the fabric-based circuits. The electroplated copper demonstrated exceptional bending and thermal stability, maintaining consistent conductivity over a wide bending range (-180° to 180°), with minimal linear resistance change after extreme twisting. Furthermore, the fabricated circuits functioned effectively as Light Dependent Resistor (LDR) based Plated Circuit Boards (PCB), demonstrating robustness and practical potential. The fabrication of conductive threads has also been explored by electroplating graphite threads. These threads displayed remarkable flexibility, maintaining consistent conductivity (0.5 Ω/cm) even under tight knots. The copper-plated textile exhibited stable resistance: 0.6 Ω across 22 °C to 55 °C and 0.5 Ω/cm under bending angles from -180° to +180°. It endured 1000 folding cycles, with resistance increasing slightly to 1.3 Ω. Furthermore, this work shows that the flexible PCBs are resistant to folding stress, environmentally friendly, and disposable, which is a significant step toward sustainable electronics. The results of this study hold significant potential applications in textile-based electrical systems, wearable electronics, and sensors.

In this paper, stability analysis of an approach for light flicker (LF) mitigation is proposed. Electric arc furnace (EAF) is one of the major sources of injecting inter-harmonics and contributing LF. Mathematical analysis of EAF current is done to determine the frequency components majourly responsible for LF. Based on the outcomes conventional control algorithm of static synchronous compensator (STATCOM) is modified to mitigate the inter-harmonics between frequency range 30Hz-70Hz, which gives advantage of capacity and capital savings. Although the proposed system reduces the flicker level Pst below 1 but it increases the system's order. In this work, stability analysis of proposed system with STATCOM is done to authenticate its practical implementation. Impedance-based small-signal modelling of the system is used to analyse the effect of current loop and voltage loop individually and together. The performance of system reveals that the proposed system is stable and can be used in practical applications. Copyright

This research unveils a transformative methodology for fabricating flexible printed circuit boards (PCBs), focusing on the unique attributes of filter paper substrates. A meticulous parametric exploration scrutinizes critical aspects such as buckling resistance, charging current, plating time, and electrode configurations for copper electroplating. Key findings highlight the exceptional stability of copper electroplating on filter paper, exhibiting robust resistance against environmental variations and bending angles spanning +180° to −180°. Utilizing higher pencil grade material and maintaining a minimum 4 cm distance with a voltage range of 3 to 1.44 V ensures uniform, controlled plating without burning, optimizing the electrode area below 1 cm2 for enhanced practicality. The research underscores the longevity and durability of copper-plated filter paper, with negligible resistance changes even after 1000 folds. Over a year, the shelf-life assessment emphasizes the excellent stability of electroplated filter paper. Practical applications, including fully functional circuits and a bio-degradable piano, underscore the versatility and real-world feasibility of the proposed electroplating technique.

This research unveils a transformative methodology for fabricating flexible printed circuit boards (PCBs), focusing on the unique attributes of filter paper substrates. A meticulous parametric exploration scrutinizes critical aspects such as buckling resistance, charging current, plating time, and electrode configurations for copper electroplating. Key findings highlight the exceptional stability of copper electroplating on filter paper, exhibiting robust resistance against environmental variations and bending angles spanning +180° to −180°. Utilizing higher pencil grade material and maintaining a minimum 4 cm distance with a voltage range of 3 to 1.44 V ensures uniform, controlled plating without burning, optimizing the electrode area below 1 cm2 for enhanced practicality. The research underscores the longevity and durability of copper-plated filter paper, with negligible resistance changes even after 1000 folds. Over a year, the shelf-life assessment emphasizes the excellent stability of electroplated filter paper. Practical applications, including fully functional circuits and a bio-degradable piano, underscore the versatility and real-world feasibility of the proposed electroplating technique. © 2024 Wiley-VCH GmbH.

With the emerging smart grid environment, information flow between generation, transmission and distribution centres increases. The huge information flow sometimes creates noise in the form of voltage signals that affects many working areas of the grid, one of which is power quality. Hence, a need arises for a power quality enhancement algorithm that is robust against the noise. Maximum Versoria criteria (MVC)-based control has found many applications in signal processing due to its advantage to reject impulsive noise. In this work, an attempt has been made to deploy MVC to enhance the quality of power flow at the distribution side by targeting issues like harmonics in the current, unbalance in load, voltage management at the point of common coupling (PCC), and reactive power requirement of the load with its ability to work in the impulsive noise. The performance of the algorithm is examined in MATLAB/Simulink as well as in a real-time environment to validate its performance for industrial applications. The algorithm has shown its advantage of less complexity and enhanced performance due to its ability to robustness against noises.

Renewable energysources (RESs) based islanded microgrid structure is susceptible to voltage and frequency fluctuations. The 'Electric Spring' (ES) stands out as a highly effective solution for strengthening operational flexibility and seamlessly integrating RESs. This paper presents a unique concept of combining the three phase Back-to-Back Electric Spring (BTBES) control topology to Self-Excited Induction Generator (SEIG) which supplies power to Critical Load (CL) and Non-Critical Load (NCL). The series inverter of BTBES is used to maintain constant voltage profile across the CL during system imbalance using 'in-phase' compensation method. The shunt-connected inverter upholds the series inverter by keeping constant DC link voltage. This shunt inverter mitigates the current harmonics of the microgrid arising due to non-linear loading by current control loop with Hysteresis Band Current Controller (HBCC). The validation of BTBES effectiveness under various linear and non-linear load variations on both CL and NCL side demonstrates system's resilience to changing load conditions. The paper effectively integrates theoretical analysis, MATLAB simulation studies, and experimental validation through Real time power Hardware-in-Loop (HIL) testing to present a thorough evaluation of the BTBES control. This integrated approach used in this paper ensures credibility and applicability of the proposed BTBES in an islanded microgrid system.