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Abstract This study focuses on stabilizing a bidirectional inductive wireless power transfer (WPT) system using an event‐triggered approach. It is only assumed the inductor currents on both the primary and pickup sides are measurable, and they are sent synchronously to the controller via a digital channel. To estimate the unmeasured states and maintain plant stability, a full‐order state observer and an observer‐based controller have been developed. The control parameters are optimized through a genetic algorithm to achieve the desired output response. An emulation methodology is then applied to create an output‐based event‐triggering condition. This condition ensures the stability of the closed‐loop system even in the presence of communication constraints. To prevent Zeno sampling, a minimal time interval between two transmissions is enforced using time‐regularization techniques. Furthermore, the performance of the event‐triggered controller is enhanced by solving a linear matrix inequality condition, which further reduces the number of transmission instances. The methodology offers a systematic and optimal design for the bidirectional inductive WPT system. It eliminates the need for manual tuning of control parameters, which is particularly beneficial given the system's complex nature. To address both continuous‐time and discrete‐time dynamics, the entire system is represented as a hybrid dynamical system, making it more intuitive for networked control systems. The efficiency of this approach is assessed through numerical simulations of a WPT system, demonstrating its effectiveness. The results show that the average intertransmission interval has been increased from 0.0799 to 0.1782 s, that is, the proposed event‐triggering strategy reduced the number of transmissions to more than 50% compared with conventional periodic sampling.

The sun serves as the primary energy source, providing our planet with the essential energy for sustaining life. To efficiently harness this energy, photovoltaic cells, commonly known as PV cells, are employed. These cells convert the solar energy they receive into electrical energy. The operational point of the solar cell, delivering maximum output power, is referred to as the maximum power point (MPP). However, as light availability and temperature fluctuate throughout the day, the MPP also varies accordingly. To maintain constant operation at the MPP, Maximum Power Point Tracking (MPPT) algorithms are employed to trace the MPP during module operation. These algorithms can be categorized into four groups: classical, intelligent, optimization, and hybrid, based on the tracking algorithm utilized. Each MPPT algorithm, existing in these categories, comes with its own set of advantages and limitations. This paper extensively reviews fifteen algorithms categorized under different groups. The review concludes with a comparative analysis of these algorithms, considering various parameters such as cost, complexity, tracking accuracy, and sensed parameters in a succinct manner. The paper focuses on elucidating the necessity of MPPT algorithms, their classification as per existing literature, and a comparative assessment of the studied MPPT algorithms. This comprehensive review aims to address advancements in this field, paving the way for further research.

Abstract The utilization of switched inductors, involving parallel charging and series discharging of inductors, is extensively embraced in diverse DC–DC converters for attaining high voltage gain; nevertheless, the stress on switch voltage and diode current escalates considerably with an increased count of inductors integrated into the switched inductors network. In the classical multistage switched inductor converter, the switch voltage aligns with the output voltage, and the diode experiences a high current as the number of stages increases. This research recommends a DC–DC multistage converter for energy conversion and high voltage gain with low stress. In this paper, a novel multistage switched inductor converter is introduced and designed to attain higher voltage gain while mitigating the stresses on switch voltage and diode current. The proposed circuit is created by replacing the standard multistage switched inductor converter's possible diodes with power switches. All of the switching devices are connected in such a way that the output voltage and input current are shared by all of the switches and diodes, respectively. As a consequence, the voltage stress on switches and the current stress on diodes are comparatively low, resulting in a high efficiency compared to a typical multistage switched inductor converter. It's interesting to note that the proposed converter and a typical multistage switched inductor converter both require the same amount of components. Different operation modes, analysis, a non‐ideal model, and a comparison of the suggested and recently constructed converters are discussed. The effectiveness and performance of the circuit are validated experimentally.

Linear induction machines (LIMs) find widespread adoption in various applications, owing to their inherent advantages such as low noise, compact turning radius, and excellent climbing capability. LIMs are extensively utilized in linear metro applications. However, in practical operations, the output thrust shrinks with the increase in speed, which is attributed to end effects. This phenomenon leads to a reduction in efficiency. In addition, fluctuations in the normal force impact system stability, posing disturbances to the suspension system. To address these challenges, this paper suggests a finite-set model predictive thrust control (FS-MPTC) for a drive system employing a linear induction motor (LIM). The FS-MPTC optimizes the duty cycle for the active voltage vector and allocates the remaining period to one of the zero voltage vectors. The selected zero voltage vector reduces the switching transition between it and the active voltage vectors. The duty cycle is calculated for the six voltage vectors by incorporating the deadbeat concept and the derivative value for the electromagnetic thrust. In the prediction stage of the FS-MPTC, the computed duty cycle and the corresponding voltage vector are used simultaneously and repeated for the six voltage vectors. The cost function comprises two terms: the error between the reference thrust and predicted thrust value as the first term and the error between the rated primary flux linkage and its predicted value as the second term. The reference thrust is generated from the outer speed control loop. To validate the effectiveness of the proposed control approach, Japanese 12000 linear induction machine parameters are employed for verification. Comparative analysis of the performance between the suggested control method with the optimal duty cycle and the same process with a fixed duty cycle demonstrates superior performance when utilizing the optimal duty cycle. Finally, the proposed FS-MPTC with the optimal duty cycle offers a promising solution to enhance the operational efficiency of the LIM-based drive systems.

High gain single switch DC-DC converter for Proton Exchange Membrane Fuel Cell (PEMFC) with Neural-Network (NN) algorithm based Maximum Power Point Tracking (MPPT) technique to drive Electric Vehicle (EV) is proposed in this paper. Apart from many maximum power extraction techniques, Neural Network (NN) based algorithm control is proposed, which uses Radial Basis Function Network (RBFN) to harvest maximum power from PEMFC under different temperature variations, which is compared with traditional Incremental Conductance (InC) method. Apart from it, a novel Single Ended Primary Inductor (SEPI) converter (boost converter) with the Coupled Inductor and Switched-Capacitor Circuit (CI + SCC) is designed to lower stress in the voltage across the switch with improved voltage gain to meet drive train (Three-Phase BLDC Motor) scenarios. Proposed PEMFC performance with RBFN-based MPPT technique integrated to drive train using a novel high gain converter is simulated using MATLAB/Simulink and implemented using dSPACE-DS1104 real-time controller. The compact sizing of the converter is proposed to integrate with PEMFC, which would be suitable for low-power EV applications.

This research work addresses automatic generation control of multiple arenas and causes under various system disturbances. Sources within arena-1 comprises thermal, bio-diesel, in arena-2 sources represent thermal elements, in arena-3 sources are thermal and hydro units. An innovative endeavor has been undertaken to employ conglomerate controller with the amalgamation of proportional-integral (PI) (integer-order) in addition fractional order proportional-derivative (FOPD). Various examination manifests the fineness of PI(FOPD) overtop additional integer order controllers from perspective concerning reduced grade of crown overshoot, expanse-of-instabilities, crown undershoot in addition to subsiding period. In determination to attain the controller’s features biologically enthused meta-heuristic artificial rabbit optimization is pragmatic. The minimum cost function value has been achieved as 0.000309 for the artificial rabbit optimization in comparison to various established optimization technique along with the proposed PI(FOPD) controller. It is likewise detected that occurrence of inexhaustible sources like realistic dish-Stirling thermal system in arena-1, geothermal power plant and precise wind turbine system styles the structure meaningfully improved related to origin structure when judged exclusively or all together. Accomplishment in presence of interline power flow controller besides combination of energy stowage elements alike redox flow battery in addition solid oxide fuel cell is as well inspected using PI(FOPD) controller, that offers with notable consequence in dynamic presentation in each cases separately. It has been clearly observed that in presence of all the renewables, in case of frequency deviation crown overshoot, crown undershoot, and subsiding period are 0.0053, 0.0131, and 24.32 respectively. These values are showing improvements in comparison to the individual presence of renewables in each arena. Similarly, with the presence of both SOFC and RFB for tie line power between arena-1 and areana-3, the crown overshoot, crown undershoot, and subsiding period are 0.00018, 0.0013, and 22.63 respectively. These values are showing improvements in comparison to the individual presence of Solid Oxide Fuel Cell without battery energy storage in each arena. Also, PI(FOPD) parameters values at nominal condition are appropriate for random pattern of disturbance needs no optimization, which justified the reliability of the suggested controller.© 2017 Elsevier Inc. All rights reserved.

There is an increasing interest in achieving global climate change mitigation targets that target environmental protection. Therefore, electric vehicles (as linear metros) were developed to avoid greenhouse gas emissions, which negatively impact the climate. Hence, this paper proposes a finite set-model predictive-based current control (FS-MPCC) strategy of linear induction motor (LIM) for linear metro drives fed by solar cells with a beta maximum power extraction (B-MPE) control approach to achieve lower thrust ripples and eliminate a selection of weighting factors, the main limitation of conventional model predictive-based thrust control (which can be time consuming and challenging). The B-MPE control approach ensures that the solar cells operate at their maximum power output, maximizing the energy harvested from the sun. Considering a single cost function of primary current errors between the predicted values and their references in αβ-axes, the proposed method eliminates the need for weighting factor selection, thus simplifying the control process. A comparison between the conventional and the presented control method is conducted using MATLAB/Simulink under different scenarios. Comprehensive simulation results of the presented system on a 3 kW LIM prototype revealed that the introduced system based on FS-MPCC surpasses the conventional technique, resulting in a maximum power extraction from solar cells and a suppression of the thrust ripples as well as an avoidance of weighting factor tuning, leading to fewer computational steps.

Abstract In recent years, common ground (CG)‐type transformerless (TL) inverters have been paid more attention. However, the existing topologies have more voltage stress on either switch or on capacitor voltage or in both. This article proposes a novel five‐level TL inverter topology with a CG type and a voltage stress reduction on power components. The proposed topology offers less component count and a simple structure. Here, the quasi‐soft charging (QSC) technique is proposed to minimize the high charging current during the capacitor charge. Since the proposed topology is the family of switched capacitors (SC), the determination of SC and QSC is presented. A detailed comparison of the proposed topology with other recent five‐level topologies is presented, and the proposed topology's advantage is highlighted. Further, the performance of the proposed topology is verified in simulation software and verified in a scale‐down hardware setup developed for 400 W. The various experimental results are presented to ensure the feasibility of the proposed topology.

Integrating energy sources is essential for having a sustainable energy supply to drive critical loads. Several types of multi-input converters (MICs) can be developed. However, most of them operate with a time-sharing-based scheme, which means that one energy source is utilized at a particular time, and the remaining sources are idle. This control scheme leads to the underutilization of both the converter and input energy sources. In this regard, this paper proposes a configuration of a single switch dual–input single-output (S-DISO) DC-DC converter, which has a simple structure with a reduced number of switches. It can operate without operational constraints on input energy sources or duty ratio utilization. Performance and comparative analysis are presented in different aspects. The effectiveness of the converter performance is validated using hardware experiments. Compared to the theoretical values, a 240 W laboratory prototype hardware circuit is developed and verified.

This article comprehensively reviews recent Electric Vehicle (EV) charging infrastructure, technology, and issues related to charging station identification. A literature study on the above key areas shows an increasing consideration of EVs over the past decade. Further, the recommendations for user-friendly selection of the Charging Station (CS) are discussed. The transport sector is one of the leading contributors to global warming. It has a high dependence on fossil fuels such as petrol and diesel, which are expected to be scarce shortly. Therefore, EVs have attracted considerable attention as they can minimize fuel consumption and emissions. For the last few years, studies related to Plug-in-Hybrid Vehicles (PHEVs)/EVs have drawn the researcher’s attention. Moreover, several technical articles associated with charging technologies with available infrastructures are discussed, and we highlighted their pros and cons, particularly in charging infrastructure, and the charging power and power transfer between EV and grid are broadly discussed. From a customer perspective, the selection of charging stations and associated problems are presented. Finally, the suggestions for the user-friendly selection of charging stations are discussed.

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.

This paper proposes a new generalized switched-inductor-capacitor module for a non-isolated dc-dc converter with low voltage dc source applications. Further, the proposed module can be extended to an $n$ number of modules to achieve high voltage gain. The derived structure has low voltage stress on power components. This structure benefits the designer by allowing him/her to choose a low $r_{DS}$ (ON) switch due to the low voltage stress across the semiconductor devices, resulting in high efficiency and low cost. In most dc/dc converters, the voltage stress on the output diode will equal the output (high) voltage ( $V_{o}$ ). But in the case of the proposed topology, the diode voltage will be the difference between $V_{o}$ and the input voltage ( $V_{g}$ ), which eases the reverse recovery problem. The key metrics of the derived topology, such as component count, voltage stresses, and gain factor, are analyzed to compare with similar existing topologies. The scaled down prototype setup is developed for 200 W with an efficiency of 93%. Finally, various experimental results are discussed for the different duty cycles.

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.

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.

This study proposes the design of quantised state-feedback controller using a Delta-Modulator ( $\Delta $ -M) for linear networked systems. This modulator can be considered as one type of sliding mode quantiser (SMQ) and offers several advantages such as lower design complexity, lower cost, and less noisy. The stability conditions of both the continuous-time and the discrete-time $\Delta $ -M based quantised control systems are derived. The bounds of the switching function, which ensure that the steady state behaviour of the system is periodic, are derived. The effectiveness of the $\Delta $ -M based quantised control system is investigated using a ZigBee protocol based experimental communication network with inherent imperfections associated with a real-time network. It is shown that the designed quantised state-feedback controller could achieve the desired performance.

The robust stabilization of doubly fed induction generators in wind turbines against external disturbances is considered in this study. It is assumed that the angular speeds of wind turbines can only be measured and sent to the controller in a discrete-time fashion over a network. To generate the sampling times, three different triggering schemes were developed: time-triggering, static event-triggering, and dynamic event-triggering mechanisms; moreover, performance comparisons were conducted between such approaches. The design methodology is based on emulation, such that the plant is first stabilized in continuous-time where a robust feedback law is constructed based on the linear quadratic Gaussian regulator (LQG) approach. Then, the impact of the network is taken into account, and an event-triggering mechanism is built so that closed-loop stability is maintained and the Zeno phenomenon is avoided by using temporal regularization. The necessary stability constraints are framed as a linear matrix inequality, and the whole system is modeled as a hybrid dynamical system. A numerical simulation is used to demonstrate the effectiveness of the control strategy. The results show that the event-triggering mechanisms achieve a significant reduction of around 50% in transmissions compared to periodic sampling. Moreover, numerical comparisons with existing approaches show that the proposed approach provides better performance in terms of the stability guarantee and number of transmissions.

The integration of communication channels with the feedback loop in a networked control system (NCS) is attractive for many applications. A major challenge in the NCS is to reduce transmissions over the network between the sensors, the controller, and the actuators to avoid network congestion. An efficient approach to achieving this goal is the event-triggered implementation where the control actions are only updated when necessary from stability/performance perspectives. In particular, periodic event-triggered control (PETC) has garnered recent attention because of its practical implementation advantages. This paper focuses on the design of stabilizing PETC for linear time-invariant systems. It is assumed that the plant state is partially known; the feedback signal is sent to the controller at discrete-time instants via a digital channel; and an event-triggered controller is synthesized, solely based on the available plant measurement. The constructed event-triggering law is novel and only verified at periodic time instants; it is more adapted to practical implementations. The proposed approach ensures a global asymptotic stability property for the closed-loop system under mild conditions. The overall model is developed as a hybrid dynamical system to truly describe the mixed continuous-time and discrete-time dynamics. The stability is studied using appropriate Lyapunov functions. The efficiency of the technique is illustrated in the dynamic model of the tunnel diode system.

Hybrid power systems based on renewable energy sources and diesel generators are efficient solutions for supplying electricity to remote and off-grid locations. One of the most crucial problems in hybrid power systems is frequency regulation, which is established by balancing the supplied power with the load demand using the load frequency control approach. Since most feedback signals are analog and the control setups are digital, the resulting control system is a sampled-data system, which requires careful designs for both the control law and the sampling frequency to guarantee closed-loop stability. This paper is concerned with the state-feedback load frequency regulation for hybrid wind–diesel power systems under event-triggered implementation. It is assumed that the full state measurement is available for feedback and that sensors and controllers communicate over a shared digital network. To mitigate the communication load on the network, an event-triggering mechanism is constructed by emulation, based on the time-regularization principle in the sense that each consecutive triggering instant is speared by a specified minimum dwell time. The closed-loop system is described as a hybrid dynamical system to account for mixed dynamical behaviors naturally arising in networked control systems. By means of appropriate Lyapunov functions, the closed-loop stability is ensured under the proposed triggering rule. Moreover, the enforced dwell time between transmissions ensures that the accumulation of sampling times is prevented, which is crucial for the event-triggering condition to be implementable in practice. The required conditions to apply this technique are derived in terms of a linear matrix inequality. Numerical simulations on an isolated hybrid power system were implemented to demonstrate the efficiency of the proposed method. Comparative simulations with relevant techniques in the literature were carried out, which showed that the proposed approach can produce fewer transmission numbers over the network.

This article suggests a hybrid DC microgrid (HDCMG) with different levels of DC bus voltages to use for various types of loads. The available sources in the HDCMG are wind generating systems (WGSs), photovoltaic (PV) systems, battery banks, and the AC grid for emergencies. The various levels of the DC bus voltages are 760 V, 380 V, and 48 V for different application uses such as electric vehicles and home applications. In addition, the controller plays an important role in the proposed system to achieve the desired DC bus voltage levels and extract the maximum power point (MPP) from the WGS and PV systems. In order to check the power continuity for the critical loads and improve the overall system performance, a suggested energy management strategy (SEMS) is developed. The SEMS is based on the optimum generated power and the state-of-charge (SOC) of the battery banks. Further, the SEMS is developed as a way to prevent battery storage from overcharging and deep discharging. The mathematical relations of the proposed HDCMG and MPP tracking are described. The bidirectional 3-Φ inverter connects the 760 V bus voltage to the AC grid for regulating this DC bus by absorbing the excess power or supplying the required power during the shortage in the generation and the low SOC of the battery storage. Buck converters with controlled duty cycles rather than constant duty cycles are used to obtain 380 V and 48 V from 760 V to achieve better dynamic responses. The overall HDCMG is evaluated using the MATLAB/Simulink package under different working cases to verify the capability of the control system and the PEMS. The obtained results are discussed and show the good performance and the capability of the overall system under the different scenarios, including (i) a comparison between variable duty and constant duty; (ii) high/low generated power and the SOC of the battery in the acceptable region; (iii) high/low generated power and the SOC of the battery in the critical region; and (iv) high/low generated power and the SOC of the battery in the overcharging region.

The recent progress in the dynamic wireless power transfer (DWPT) system brings feasibility to increase the driving range of an electric vehicle (EV). The on-road wireless charging system reduces the volume of the EV’s battery and charging the vehicle while driving. So, the powered roadways can potentially decrease the dependency on heavy-sized batteries for EV applications. The capability of transferring maximum power from the ground surface to the vehicle requires the critical design of the entire DWPT system. The various factors such as wireless charging pads, power electronic converters, compensators, and controllers influence the power transfer rate of the system. An appropriate impedance matching network assists the system during power transfer. Moreover, the design of coils in DWPT needs to consider the sensitive misalignment tolerance, safety issues, complex design, and cost factors. In this article, the basic topologies, history, and fundamentals of the DWPT charging system are discussed. In addition, the impact on the power grid due to the DWPT system and factors involved in microgrid integration are discussed. However, the current scenario of different compensators, converters, and design topologies proposed in the dynamic charging system is included. This article presents a comprehensive overview and challenges involved in a DWPT system such as the design of a power converter, charging couplers, compensation network, foreign object detection system, economic factors, and microgrid-integrated DWPT system. An economic analysis, electromagnetic compatibility, and interference of the charging system are also analyzed vastly. The human exposure level with its allowable limits developed for the wireless power transfer system is discussed.

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.

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.

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.

This article presents a single-stage five-level boost inverter (5L-SBI) topology with reduced power components. The proposed topology falls under the self-balanced switch-capacitors (SCs) type and combines both a DC/DC boost converter and inverter with a switched-capacitor cell. The advantages of proposed topologies include the following: the number of switch counts is reduced, the maximum voltage gain is two times higher than the input voltage, and the capacitor’s charging current is suppressed. Further, the proposed topology cascaded, and three-phase extensions are presented. To attest, the advantages of the proposed topology are thoroughly compared with other recent SCI topologies. The proposed topology is verified under dynamic loading conditions, and the results are presented, considering a 600 W laboratory prototype model.

Electric Vehicles (EV) offer eco-friendly transportation, but the growth of the electric vehicle market year over year is very minimal due to insufficient EV charging stations, slow charging time and grid instability during peak hours. This paper proposes a high gain, fast charging DC–DC converter and a control algorithm for grid integrated Solar PV based Electric Vehicle Charging Station (SPV-EVCS) with battery backup. The proposed converter and its control algorithm’s performance are investigated in three different modes using MATLAB/Simulink tool and the simulated results are validated with Real-Time Digital Simulation (RTDS) in OPAL-RT. The observed results meet the Power Quality limits of an IEC61000-3-2 standard and met the level-4 dc charging standard IEC61851.

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 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.

This article presents a novel quadruple boost inverter (QBI) with an integrated boost stage that comprises an inductor, a capacitor, a switch, and an input source. The inductor on the input side limits the inrush current and also the capacitor charging current ripples. The QBI topology comprises a dc source, an input inductor, nine switches, three diodes, and capacitors. This produces a nine-level waveform, which reduces the need for additional filters such as inductors and capacitors. The proposed QBI is elementary, compact, and needs fewer components than existing nine levels inverter. Compared to the typical triangular carrier-based sinusoidal pulse width modulation, the newly developed parabolic level-shifted carrier has a much greater RMS value. Another advantage of the proposed topology is extension for generating higher voltage levels without increment in the blocking voltage across the switches. This makes the topology ideal for medium voltage high power applications. The output voltage has been determined in terms of selection, sizing, and expression. The proposed QBI is compared to existing similar nine-level inverters in order to assess its efficacy. The experiment is performed on a laboratory prototype to state the practical feasibility of QBI topology for the inductive load, variation in input, load, and modulation index.

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.

The present study proposes a new dynamic two-level quantizer, called as hybrid delta modulator ( $\Delta _{H} $-M), which combines the features of both delta-modulator and delta-sigma modulator. In the transient state, the $\Delta _{H} $-M exhibits the dynamical behaviour of delta modulator (Δ-M) while in steady state, its behaviour is similar to delta-sigma modulator ( $\Delta \Sigma $-M). This study investigates about various dynamics of the proposed $\Delta _{H} $-M in both continuous and discrete-time domains. The stability conditions of $\Delta _{H} $-M are derived using the theory of sliding and quasi-sliding mode. The theoretical results are validated through extensive simulations. Abbreviations: Δ-M: delta modulator; $\Delta _{H} $-M: hybrid delta modulator; $\Delta \Sigma $-M: delta sigma modulator; ADC: analogue to digital converter; CT: continuous-time; DAC: digital to analogue converter; DT: discrete-time; NCS: networked control system; QSM: quasi-sliding model; QSMD: quasi-sliding mode domain; SS: steady state; TP: transient process

This paper presents a new multilevel converter with a reduced number of power components for medium voltage applications. Both symmetric and asymmetric structures of the presented multilevel converter are proposed. The symmetric topology requires equal dc source values, whereas the asymmetric topology uses minimum switch count. However, both structures suffer from high blocking voltage across the switches. To reduce the blocking voltage on switches, an optimal topology is presented and analyzed for the selection of the minimum number of switches and dc sources, while maintaining a low blocking voltage across the switches. A comparative analysis with recently published topologies was performed. The simulation results, as well as the comparative analysis, validated the robustness and effectiveness of the proposed topology in terms of the reduced power loss, lowered number of components, and cost. Furthermore, in addition to the simulation results, the performance of the proposed topology was verified using experimental results of 9, 17, and 25 levels.

In this paper, we consider the stability and various dynamical behaviors of both discrete-time delta modulator (Δ-M) and adaptive Δ-M. The stability constraints and conditions of Δ-M and adaptive Δ-M are derived following the theory of quasi-sliding mode. Furthermore, the periodic behaviors are explored for both the systems with steady-state inputs and certain parameter values. The results derived in this paper are validated using simulated examples which confirms the derived stability conditions and the existence of periodicity.

In remote locations such as villages, islands and hilly areas, there is a possibility of frequent power failures, voltage drops or power fluctuations due to grid-side faults. Grid-connected renewable energy systems or micro-grid systems are preferable for such remote locations to meet the local critical load requirements during grid-side failures. In renewable energy systems, solar photovoltaic (PV) power systems are accessible and hybrid PV-battery systems or energy storage systems (ESS) are more capable of providing uninterruptible power to the local critical loads during grid-side faults. This energy storage system also improves the system dynamics during power fluctuations. In present work, a PV-battery hybrid system with DC-side coupling is considered, and a power balancing control (PBC) is proposed to transfer the power to grid/load and the battery. In this system, a solar power conditioning system (PCS) acts as an interface across PV source, battery and the load/central grid. With the proposed PBC technique, the system can operate in following operational modes: (a) PCS can be able to work in grid-connected mode during regular operation; (b) PCS can be able to charge the batteries and (c) PCS can be able to operate in standalone mode during grid side faults and deliver power to the local loads. The proposed controls are explained, and the system response during transient and steady-state conditions is described. With the help of controller-in-loop simulation results, the proposed power balancing controls are validated, for both off-grid and on-grid conditions.

The solar photovoltaic (PV) system is emerging energetically in meeting the present energy demands. A rise in PV module temperature reduces the electrical efficiency, which fails to meet the expected energy demand. The main objective of this research was to study the nature of OM29, which is an organic phase change material (PCM) used for PV module cooling during the summer season. A heat transfer network was developed to minimize the experimental difficulties and represent the working model as an electrical resistance circuit. Most existing PV module temperature (TPV) reduction technology fails to achieve the effective heat transfer from the PV module to PCM because there is an intermediate layer between the PV module and PCM. In this proposed method, liquid PCM is filled directly on the back surface of the PV module to overcome the conduction barrier and PCM attains the thermal energy directly from the PV module. Further, the rear side of the PCM is enclosed by tin combined with aluminium to avoid any leakages during phase change. Experimental results show that the PV module temperature decreased by a maximum of 1.2 °C using OM29 until 08:30. However, after 09:00, the OM29 PCM was unable to lower the TPV because OM29 is not capable of maintaining the latent heat property for a longer time and total amount of the PCM experimented in this study was not sufficient to store the PV module generated thermal energy for an entire day. The inability of the presented PCM to lower the temperature of the PV panel was attributed to the lower melting point of OM29. PCM back sheet was incapable of dissipating the stored PCM’s thermal energy to the ambient, and this makes the experimented PCM unsuitable for the selected location during summer.

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.