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For smart cities, the successful large-scale implementation of solar PV technology, Quality Certification and Standards are mandatory. The International Electrotechnical Commission (IEC) is a global organization for standardization consisting of all IEC national committees. The IEC PV standards comprise IEC technical committee 82 solar PV Energy System (IEC TC82) which develops and adopts all Photovoltaic related standards. There are nearly 80 standards applicable to photovoltaic and five working groups in IEC TC82. For necessary safety requirements ‘Quality and Standards’ technologically need to be revised and up to date. This paper presents PV standards developed by various technical committees worldwide, mainly focusing on various IEC PV standards, gaps identified by them and the recommendations provided by the committee in recent times. The breakup costs of the various sub-systems of a PV installation with an illustrative example for India is also discussed. It is intended to provide a guideline for consumers and investors, opting for solar PV installations.

Global climatic changes and increased carbon footprints provided the main impetus for the decrease in the use of fossil fuels for electricity generation and transportation. Matured manufacturing technologies of solar PV panels and on-shore and off-shore windmills have brought down the cost of generation of electricity using solar energy on par with conventional fossil fuel. Initially, solar and wind power generation was envisioned for microgrids, serving small local communities. However, advancements in power electronics have now facilitated large solar and wind farms to be integrated with main power grids. In this context, hosting capacity, which is the amount of distributed energy resources a grid can accommodate, without significant infrastructure up-gradation, has gained importance. In determining the hosting capacity at a particular location, the uncertainties of wind and solar power generation play a role. Effective forecasting models using time-series weather data can be built to predict wind and solar power generation. This forecast is essential to ensure proper grid operation and control when renewable energy sources are already installed. The forecast is also useful in the planning stages for investment decisions and distribution system planning. While long-term forecasts are rarely needed for the operation of integrated grids, accurate short-term predictive models are necessary for scheduling. This paper presents an extensive review of various forecast models available in the literature. The study mainly focuses on the short-term forecast, providing a critical review of the duration of data used in each model and a synoptic comparison of their performance indices.

The main aim of this paper is to introduce a framework for the design and modelling of a photovoltaic (PV)-wind hybrid system and its control strategies. The purpose of these control techniques is to regulate continuous changes in the operational requirements of the hybrid system;currently, in power system networks, the distribution of energy plays a major role in maintaining power reliability in distribution systems. In this study, the proposed hybrid system was incorporated with a combined PV and wind energy system. Maximum power point tracking (MPPT) methods have been proposed to achieve maximum efficiency from the designed system. In addition, this study focused on improving the stability of the hybrid system. To improve the power quality and transient stability of the proposed system, we introduce a novel control strategy called the distributed power flow controller (DPFC) implementation with an optimization technique called the lion optimization algorithm(LOA)technique. This LOA control technique was developed for the first time in the application of a DPFC controller in a grid-connected system. The control technique was developed using signals from the system parameters, that is, voltage and current. To tune these parameters, this study used fuzzy logic and lion optimization techniques. The proposed system with controllers was tested in MATLAB/Simulink and the results were compared.

Renewable powered dc microgrid is more cost-effective, simple, reliable, highly efficient, and scalable than the traditional electric grid. This paper provides an overview of high gain dc converter topologies for dc microgrids. This research's primary objective is to impart a unique extensive, comparative, and perceptive analysis in high gain converter configurations. The most recently reported research articles are considered for discussion in this paper. Initially, based on the structural configurations, the converters are segregated and are grouped into four categories, such as Replacement, Reduced Redundant Power Processing (R2P2), Incorporation, Integration (R2I2) techniques. Secondly, based on the dynamic and steady-state analysis, the topological converter configurations are comparatively analyzed. A few topologies' mathematical modeling is also discussed to obtain a comprehensive insight into the converter's dynamic behavior. An extensive analysis, comparisons, and assessment of these converters with diverse configurations are acquainted with tables and figures are presented for choosing an appropriate converter suitable for dc grid application. The pros and cons of the topology derivation under each categorization are presented for benefitting the researchers in selecting the topological configuration method. In the end, the comparison results of the high gain converter clusters are summarized, and recommendations are given, which leads to the guidelines for selecting a significant high gain topology for a specific application. Furthermore, the constraints considered for topology derivation with the type of analysis carried out are presented. This gives a way to find the scope for future research under this area which is finally offered. This study will also provide an insight into the derivation of several configurations of the novel high gain dc-dc converter in the field of dc microgrid.

The concerns over the increase in carbon footprints and global climatic changes have given momentum to find ways that reduce the use of fossil fuels to generate electricity. Offshore and onshore windmills for electricity generation are viable options for bulk power generation. A wind generation system has a variable frequency variable voltage supply at the induction generator terminals in response to the changes in the wind velocity and in turn, the speed of the wind turbine. There is a need for an additional power electronic interface to maintain the frequency and voltage at the terminals of the wind generator constant. This paper introduces a novel three-phase Bifurcated Winding Induction Generator (BWIG) comprising a bifurcated set of stator windings. A prototype model has been developed by bifurcating the stator windings of a three-phase induction machine. One part of the winding acts as the excitation winding, and the other half is used as output winding capable of producing three-phase voltages at a constant frequency at all speeds of the prime over. The machine is tested for sub and super synchronous speeds and the characteristics plotted. The flux analysis of the machine is simulated using Ansys Maxwell software. The voltage is controlled by a simple off-on control implemented using a digital controller, TMS320F28335.

The conventional neutral point clamped (NPC) multilevel inverter topology needs voltage balancing circuits to balance the dc-link capacitor, the number of component count is high and output voltage is half of the input voltage which increase the size of the source side dc/dc converter in PV applications. In this paper, a new topology of seven level neutral point clamped inverter is developed. The proposed inverter has a self-voltage boosting capability using a floating capacitor to boost the output voltage one and half of the input voltage. In this proposed topology, no additional sensors are required for the floating capacitor voltage stability, which results in minimizing the complexity of designing the inverter. The direct link between the neutral point and the mid-point of the dc-link capacitors significantly reduces the leakage current and common mode voltage in this inverter. A thorough comparison between the developed topology and recent suggested topologies is carried out which set the benchmark for the proposed one due to its lower switch count and higher voltage gain. The proposed topology is verified in simulation and prototype hardware model and results are discussed with dynamic load variations. The efficiency of the inverter is 97.1% @200W and low as 88.1 % @ inductive load. The voltage THD is 17.01% for simulation and 19.3% I for experimental is results.

Solar insolation is sun radiation converted to electrical energy and injected into the utility network using grid-connected solar power plants. Recently, in many nations’ electricity grids, the share of power generated using solar photovoltaic (PV) power plants is rapidly increasing. In this case study, solar insolation levels on different latitudes with fix & two seasonal tilt angles have been measured using Meteonorm® software. For these latitudes, fourteen airport locations have been chosen across the globe. From the case study, it has been evident that a double seasonal tilt angle provides more global insolation as compared to fix tilt angle with a suitable azimuth angle. There is also a reduction in insolation level at fixed and two seasonal tilt angles if going away from the equator. Further, up to three seasonal tilt angles, there is sufficient enhancement has been observed in solar insolation. It is also analyzed that for multiple seasonal tilt angle based solar PV Plant, month-wise tilt angle selection is more important. Further Average, Rectangular, and Trapezoidal methods have been used for estimation of cumulative inclined insolation for a specific period and compared. From the comparison, the trapezoidal method has been found optimal for accurate estimation of cumulative inclined insolation.

Power electronic converters find application in diverse fields due to their high power conversion efficiency. Converters are often characterized by time response specifications, robustness and stability. Conventionally, converters employ the classic PID controller. The state space average linear time invariant model of a boost converter is known to be a non-minimum phase system. This paper demonstrates that the boost converter with a PID controller using the Queen Bee assisted Genetic Algorithm (QBGA) optimization is not robust to plant parameter variations. A fractional order PID controller based on QBGA optimization proposed here is shown to have improved robustness. The controller proposed here is applicable across converters, viz., buck, boost and buck-boost, equally.

This work presents an investigation on Improved Extended Kalman Filter (IEKF) performance for induction motor drive without a speed sensor. The performance of a direct sensorless vector-controlled system through simulation and experimental work is tested. The proposed observer focuses on estimating rotor flux and mechanical speed of rotor from the stationary axis components. Extended Kalman Filters’ estimation performance depends on the system matrix’s proper value ( $Q$ ) and measurement error matrix ( $R$ ). These matrices are assumed to be persistent and are calculated by the trial-and-error method. But, the operating environment affects these matrix values. They must be updated based on the prevailing operating conditions to get high speed and accurate estimates. The values of Q and R in the Improved EKF (IEKF) algorithm are obtained using the genetic algorithm. Besides, IEKF is incorporated to reduce in computational burden for real-time applications.

For renewable sources application like smart grids, microgrids, etc. high voltage gain converter becomes a fundamental unit. In this article, a new hybrid circuit of zeta and boost converter based on active-quad-switched-inductor (AQSL) is proposed. The discontinuous input current in classical zeta circuit determines the less consumption of input source. However, the proposed hybrid zeta-boost converter provides a higher voltage gain with continuous input and output currents. It achieves higher voltage gain devoid of the high-frequency transformer, and multiple stages of diode and capacitor circuit. The mode of operation, boundary region, and non-ideal model of the proposed converter are presented. Design consideration and a comparison study with recent circuits are provided. The design circuitry of the proposed converter investigated and the functionality of the suggested circuit is validated.

The vigorous growth of electric vehicles in the field of automobile paves the way for the development of dc-dc converter. A novel high gain super Luo dc-dc converter is proposed in this article. A modification is suggested in the topology when the converters are cascaded for high gain. This suggested modification can be applied to any topology for reliable capacitor. The presented converter adds boosting (voltage multiplier) cell before the load to expand the voltage conversion ratio. This converter renders remarkable features like extended voltage gain, low voltage stress on power switches, minimal capacitor stress and less component count. The operating principle and steady-state analysis of the proposed topology is presented. The main feature of the proposed topology is reduced capacitor stress which is evaluated by reliability study with military handbook MIL-HDBK-217F. The significance of minimal capacitor stress with the failure of the capacitor is elaborated. Simulation on the derived topology is carried out with Matlab/Simulink and it validates the theoretical results. Furthermore, the proposed topology is extended with dual output which makes the restructured converter suitable for Electric vehicle application and the simulation of the dual output topology is performed and studied. The experimental results obtained from the 50 W prototype validate the complete steady-state analysis performed on the proposed topology.

One of the most challenging and interesting field in power electronics is the ability to mitigate the Electromagnetic Interference (EMI). A natural source of EMI includes the atmospheric discharge/charge phenomena and extra-terrestrial radiation. Man-made source of EMI are line radiation, auto ignition, radio frequency interference and power lines. Suppression of EMI and enhancing the Electro Magnetic Compatibility (EMC) has become essential in high frequency power electronic converters. This review article is a one stop solution for new researchers and practitioners to understand about the effects of EMI and its suppression techniques in detail.

A high number of research work is being carried out in the field of DC-DC converters to improve the performance of microgrid operation. The DC microgrid has a high level of acceptance because of the integration of renewable energy sources. In DC Microgrid, there is a need for improved DC-DC converter topologies which offer high gain, small size, enhanced efficiency, reduced voltage stress and reduced component count etc. A new Triple-Mode Active-Passive Parallel Intermediate Links (TM-A2P-IL) converter is proposed in the paper. The A2P-IL is designed by a combination of an inductor, capacitor, diode, and control switch. The proposed converter is derived by inserting A2P-IL in conventional boost converter. The proposed TM-A2P-IL converter operates in three modes and provides a high voltage gain without using a transformer, voltage multiplier stages, coupled inductor, switched inductor/capacitor circuitry. The other benefits of the proposed TM-A2P-IL converters are flexibility in the selection of duty cycles, reduced voltage stress of devices, small reactive components, single-stage power conversion. The proposed converter circuit, operating principle, steady-state analysis is studied for both CCM and DCM, discussed. The comparison between available similar type converters and the proposed converter is provided. The operation and performance of the proposed A2P-IL converter are validated through simulation and experimental work.

The Multilevel inverters (MLIs) are a new breed of power electronics converters. They are primarily used for the conversion of dc power to ac power. The two-level inverters are conventionally used to obtain ac power, but it requires operating the switches under very high switching frequency. Besides, the two-level inverter necessitates the use of LC filters with the switches operating under high dv/dt stress. The MLIs offer the advantage of utilizing several dc voltage sources to generate a stepped ac waveform with the proper arrangement of switches. Investigation of a Transistor Clamped T Type H-Bridge Multilevel Inverter (TC-TT-HB-MLI) with Inverted Double Reference Single Carrier PWM Technique (IDRSCPWM) for Renewable Energy Applications are discussed in this paper. A PV source is taken as an input to the TC-TT-HB-MLI. For different modulation indices like 0.85, 1 and 1.25, the FFT analysis is performed and presented, which corresponds to the variations in the irradiations from solar energy. A single unit of the TC-TT-HB-MLI is extended to a generalized MLI structure named Generalized Transistor Clamped T-Type H-Bridge Multilevel Inverter (GTC-TT-HB-MLI). The significant benefits of GTC-TT-HB-MLI are the multiple numbers of reductions in the switch count, and driver circuit counts for a higher number of MLI levels. Fast Fourier Transform (FFT) analysis is carried out on the MLI output to calculate the total harmonics distortion (THD). The experimental verification is performed using SPARTAN 3E-XCS250E; the gate signals are generated and provided to the switches.

The presence of stray capacitance in ZnO (Zinc Oxide) surge arresters causes hurdles in arrester operation and non-uniform voltage distribution along the arrester column, especially for High Voltage (HV) and Extra high voltage (EHV) applications. Since the magnitude of stray capacitance is directly proportional to the arrester height; the shortening of surge arresters is a preeminent method to enhance the arrester performance and voltage distribution. Particularly, this stray capacitive effect delays the arrester operation from in-action to action mode, especially against very fast surges. Moreover, the shortening of the arrester column improves the voltage distribution and hence the electric field varies between the stacks. Therefore, this research work focuses on the preparation of two new high gradient arrester materials doping with rare earth oxides. The microstructures of the newly developed materials are analyzed. It is found that there is a reduction of grain sizes and an increase of voltage gradients in the newly developed arrester materials. From this, the height requirement per unit is estimated and compared with the conventional ZnO arrester. Using these high gradient materials, the reduction of height and compactness of the arrester assembly may be achieved greatly. Thus, the developed ZnO surge arrester with high gradient materials enhances the arrester behavior with the attendant improvement of voltage distribution due to its reduced height and stray effect.

In this work, a new control methodology is proposed for Type -IV wind energy conversion system (WECS) using a self-recurrent wavelet neural network (SRWNN) control with a Vienna rectifier as the machine side converter (MSC). A SRWNN combines excellent dynamic properties of recurrent neural networks and the fast convergence speed of wavelet neural network. Hidden neurons of SRWNN contains local self-feedback loops, which provide the memory feature and the necessary information of past values of the signals, allowing it to track maximum power from WECS under varying wind speeds. The Vienna rectifier allows unity power factor operation to increase electrical efficiency. Frame angle-controlled wavelet modulation is proposed for the grid side converter (GSC). Wavelet modulated inverter produces output voltage fundamental components with higher magnitudes than those obtained from the pulse width modulated inverters. The non-linear load compensation and power quality enhancement are achieved by executing frame angle control for WM inverter. The overall system is modeled, and performance is verified in MATLAB Simulink. The hardware prototype is developed, and the switching pulses for the rectifier and inverter are generated using dSPACE1104 controller. The results prove that the system provides low harmonic content and high magnitude of the fundamental current component at the machine and grid sides and ensures maximum power operation at various wind speeds.

This paper presents a new multilevel inverter topology with reduced active switches and total standing voltage. The proposed topology can generate a high number of voltage levels in the symmetric configuration. This topology intuitively generates positive and negative cycles without an additional H-bridge unit, which considerably reduces the total standing voltage of the inverter. A cascaded structure is developed from the proposed topology to create higher voltage levels. To show the novelty of the proposed topology, a thorough comparison between the available and the proposed topologies in terms of the number of switches, standing voltages, and dc-sources is presented. Furthermore, the power loss analysis is carried out for various load values. The feasibility of the proposed nine-level inverter is verified with simulation and experimental results.

This paper presents a binary hybrid multilevel inverter (BHMLI) based grid-connected solar energy conversion system (SECS), controlled by damped second-order generalized integral (DSOGI). The BHMLI architect has a cascaded half-bridge array, which modifies the DC-link of the H-bridge of the voltage source inverter, and results in approximate reference waveform. It reduces the dV/dt of the H-bridge switches and improves output waveform quality. The DSOGI control damps the oscillations and overshoots and provides longer service period of low power switches at transient conditions. It is implemented in the multilevel inverter application for the first time in literature. The SECS is designed to inject active power to the grid, and also mitigates the harmonic and reactive power demands of the load. The cascading of n' half-bridges and one H-bridge generate (2(nC1) - 1) output voltage levels. The maximum power extraction from solar photovoltaic (PV) array is achieved through incremental conductance (IC) algorithm based maximum point tracking (MPPT) operation of the DC-DC converter. An isolated single-input multiple-output single-ended primary inductance converter (SIMO-SEPIC) realizes it. SECS with 15-level BHMLI is analyzed with extensive simulation as well as with a hardware prototype. Moreover, the shunt active filter functionality of the system at various load conditions are verified and maintained the grid power quality within the IEEE-519 standard throughout the operation. The laboratory developed setup is tested for 5 kW, 400 V, three-phase system, and the experimental analysis at steady-state and dynamic variations of load-side and insolation variations validate the theoretical claims.

This paper proposes a Resistance perturbation based maximum power point tracking (MPPT) with an adaptive control limit algorithm to extract the maximum power from solar photovoltaic (PV) array. This algorithm consists of two main functions, namely 1) resistance perturbation & observation (RP&O) and 2) adaptive resistance control (ARC) limit. The RP&O operates the PV array at maximum power point (MPP), and the ARC limit continuously monitors the resistance of the PV Rpv to determine the operating limit of MPP. The ultimate aim of proposing this algorithm is to reduce the oscillations and improve MPP's tracking performance for sudden variation in temperature and irradiance conditions. Furthermore, it does not require an expensive pyranometer or temperature sensor to track the MPP of the PV array. This paper also compares the proposed and conventional MPPT algorithm's performance. Its validation results in both MATLAB/Simulink and experimental studies are presented under constant and sudden changes in irradiance conditions.

This article proposes a $\Delta $ -Modulator ( $\Delta $ -M) based quantised output feedback controller for linear networked systems. The proposed $\Delta $ -M is essentially a 2-level quantiser, in contrast to some of the existing quantisers such as $2^{p}$ level ( $p \geq 1$ ) uniform-interval-nearest-neighbour quantiser, and offers various advantages which include lower design complexity, less noisy and lower cost. The three key components of the control system: the controller , the filter and the quantiser are designed to achieve the desired performance. The stability conditions of the $\Delta $ -M are derived and conditions for the existence of zig-zag behaviour in steady-state are determined. The performance of the proposed controller is illustrated through simulations considering practical communication network based on ZigBee protocol. The results of the simulation demonstrate that the proposed controller could effectively achieve desired performance under various imperfections of the practical communication network.

In this article, an original hybrid multilevel DC-AC converter configurations are proposed by using single-double source unit for medium voltage applications. The proposed topologies are derived by hybridization of single and double source units with polarity changer and cascaded with full-bridge converter for medium and high voltage applications. Two different hybrid topologies presented and each topology configured for both symmetric and asymmetric method. The proposed hybrid topologies compared with the conventional cascaded H-bridge converter (CHB), and the best topologies recommended for medium voltage applications. The comparison in terms of the number of switches, gate driver circuits, maximum blocking voltage by switches and total peak inverse voltages of switches presented. The proposed topologies require a small installation area and low cost. The validity of the proposed hybrid converter structures is verified by simulation using MATLAB/Simulink and hardware results. The simulation and hardware results show a good agreement with the theoretical approach.

The automobile companies are focusing on recent technologies such as growing Hydrogen (H2) and Fuel Cell (FC) Vehicular Power Train (VPT) to improve the Tank-To-Wheel (TTW) efficiency. Benefits, the lower cost, `Eco' friendly, zero-emission and high-power capacity, etc. In the power train of fuel cell vehicles, the DC-DC power converters play a vital role to boost the fuel cell stack voltage. Hence, satisfy the demand of the motor and transmission in the vehicles. Several DC-DC converter topologies have proposed for various vehicular applications like fuel cell, battery, and renewable energy fed hybrid vehicles etc. Most cases, the DC-DC power converters are viable and cost-effective solutions for FC-VPT with reduced size and increased efficiency. This article describes the state-of-the-art in unidirectional non-isolated DC-DC Multistage Power Converter (MPC) topologies for FC-VPT application. The paper presented the comprehensive review, comparison of different topologies and stated the suitability for different vehicular applications. This article also discusses the DC-DC MPC applications more specific to the power train of a small vehicle to large vehicles (bus, trucks etc.). Further, the advantages and disadvantages pointed out with the prominent features for converters. Finally, the classification of the DC-DC converters, its challenges, and applications for FC technology is presented in the review article as state-of-the-art in research.

The recent advancement in wireless body area networks (WBAN) plays an important role in remote health care systems. However, these networks are suffering from data security and privacy threats. Lack of anonymous authentication and secure data communication leads to operation failure in WBAN. Computational cost and privacy preservation are the two major hindrances for anonymous authentication in many existing schemes. Therefore, a secure and efficient privacy-preserving anonymous authentication scheme is proposed to provide data security and privacy to the users with low computational and communication cost. The performance analysis and experimental simulation results ensure that our proposed anonymous authentication method outperforms the existing systems in terms of providing data security and privacy with less computational overhead.

This paper deals with the robust fault estimation based synchronization problem for a class of fractional-order multi-weighted complex dynamic networks subject to external disturbances. Specifically, the synchronization problem is converted to an equivalent uniformly ultimately boundedness problem of the corresponding error system by use of spectral decomposition of the Laplacian and proper scalings of the faults. First, by introducing an intermediate estimator technique and using monochromatic Lyapunov function method, the sufficient condition for uniformly ultimately boundedness of the resulting error system via fault estimation based non-fragile controller is presented. Next, by using the linear matrix inequality (LMI) technique and optimization approach, the existence condition in the form of LMIs for designing the fault estimation based robust non-fragile controller is derived. Finally, two numerical examples including financial model are provided to demonstrate the validity and feasibility of the developed theoretical results.

The main attention of this paper is to tackle the issue of robust tracking and disturbance estimation for the four wheel steering vehicle by implementing a feedback control design based on the improved-equivalent-input-disturbance technique and the Smith predictor approach. The intention of incorporating the Smith predictor into the controller design is to compensate the effect of input time-delay. In addition, the improved-equivalent-input-disturbance technique is applied for dealing with the nonlinear uncertainty and external disturbances. Based on the proposed controller, both front and rear steering angles of the considered model are controlled to trace the desired position of the vehicle. More precisely, the developed criterion that ensures the desired tracking performance of the vehicle is obtained in the form of linear-matrix-inequalities based on the construction of an appropriate Lyapunov-Krasovskii functional candidate. Numerical simulation results for vehicle dynamics are presented to examine the performance of the proposed control strategy.

This paper presents the use of a delta-sigma quantizer for generalized one-bit control processing. An equivalent control strategy based on sliding-mode control is employed to derive the necessary condition for the convergence of the proposed one-bit control system in both the continuous-time and discrete-time domains. Under the convergence condition, the binary signals generated by delta-sigma quantizers in the one-bit control system effectively replace their counterpart signals in conventional control systems. This enables a significant reduction in the number of multipliers and overall hardware cost for computing the control laws in one-bit control systems. Our result is applied to design a multiplier-less one-bit generalized proportional and integral controller for the position control of an experimental prototype of a DC motor. An implementation of the one-bit control system is carried out using an FPGA platform to demonstrate the behavior of one-bit generalized proportional and integral controller and compare the results with the standard in terms of implementation efficiency. The results of the simulation and experiment show that the one-bit generalized proportional and integral controller effectively controls the system and achieves the desired specifications. At the same time, the proposed one-bit control system consumes significantly fewer hardware resources than the standard control system.

Modular Multilevel Converters (MMC) are gaining importance because of their flexible structure, re-configurable property, and simplicity of operation. The operation of MMC at a low-switching frequency (LSF) helps in enhancing the performance of the converter. This paper proposes an improved harmonics mitigation scheme for a Multilevel DC-Link Inverter (MLDCLI), which is a variant of MMC. The proposed scheme is a modified version of the conventional Nearest Level Modulation (NLM) scheme, termed as modified Nearest Level Modulation (mNLM) Scheme. The proposed scheme is effective compared to NLM because of the choice of the switching angles obtained by the use of the algorithm proposed. The MLDCLI topology is operated for twelve different configurations, and mNLM is implemented on all the configurations. Using MATLAB software, the simulation results are validated, and the same is extended to a hardware prototype. The simulation and experimental results of NLM and mNLM schemes are compared. The effectiveness of the proposed scheme is evident by the reduced voltage THD, increased rms voltage, increased rms current, and increased output power.

In significant cases, the generated voltage needs to be step-up with high conversion ratio by using the DC-DC converter as per the requirement of the load. The drawbacks of traditional boost converter are it required high rating semiconductor devices and have high input current ripple, low efficiency, and reverse recovery voltage of the diodes. Recently, the family of Multilevel Boost Converter suggested and suitable configuration to overcome the above drawbacks. In this article, hybrid DC-DC non-isolated and non-inverting Nx Interleaved Multilevel Boost Converter (Nx-IMBC) is analyzed in Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) with boundary condition and investigated in detail. The Nx-IMBC circuit combined the features of traditional Interleaved Boost Converter (IBC) and Nx Multilevel Boost Converter (Nx-MBC). The modes of operation, design of Nx-IMBC and the effect of the internal resistance of components are presented. The comparison study with various recent DC-DC converters is presented. The experimental and simulation results are presented with or without perturbation in input voltage, output power and output reference voltage which validates the design, feasibility, and working of the converter.

Water hammering is a significant problem in pumping systems. It damages the pipelines of the pump drastically and needs to identify with an intelligent method. Various conventional methods such as the method of characteristics and wave attenuation methods are available to identify water hammering problems, and the predictive control method is one of the finest and time-saving methods that can identify the anomalies in the system at an early stage such that the device can be saved from total damage and reduce energy loss. In this research, a machine learning (ML) algorithm has used for a predictive control method for the identification of water hammering problems in a pumping system with the help of simulations and experimental-based works. A linear regression algorithm has been used in this work to predict water hammering problems. The efficiency of the algorithm is almost 90% compared to other ML algorithms. Through a Vib Sensor app-based device at different pressures and flow rates, the velocity of the pumping system, a fluctuation between healthy and faulty conditions, and acceleration value at different times have been collected for experimental analysis. A fault created to analyze a water hammering problem in a pumping system by the sudden closing and opening of the valve. When the valve suddenly closed, the kinetic energy in the system changed to elastic resilience, which created a series of positive and negative wave vibrations in the pipe. The present work concentrates on the water hammering problem of centrifugal pumping AC drive systems. The problem is mainly a pressure surge that occurs in the fluid, due to sudden or forced stops of valves or changes in the direction and momentum of the fluid. Various experimental results based on ML tool and fast Fourier transformation (FFT) analysis are obtained with a Vib Sensor testbed set-up to prove that linear regression analysis is the less time-consuming algorithm for fault detection, irrespective of data size.

In the above-named work, T. Deepa should have been listed as the second co-author of the article with the affiliation of (1): School of Electrical Engineering, Vellore Institute of Technology, Chennai 600127, India. The author's biography is also provided within this correction. Additionally, the correct zip code of affiliation (1) should be 600127, and the correct statement on financial support acknowledgement should be as follows: "This work was funded by the Renewable Energy Laboratory, Department of Communications and Networks Engineering, Prince Sultan University, Riyadh, Saudi Arabia." It is necessary to mention the nature of funding provided by Prince Sultan University and to note the correction in the spelling of the university in the same statement in the published manuscript.