bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictive load accommodation in a micro-grid
Authors: Laddha Ashish , Neeli Satyanarayana , Krishnasamy Vijayakumar
Published: January 2023

This manuscript applies model prediction-based control (MPC) to accommodate the variable ac-natured load (AL) by optimally allocating the fuel cell (FC), battery, solar photovoltaic (SP) power in a four-port dc/dc converter (FPDDC). The presented work considers the FC, battery, SP, and AL at the first, second, third, and fourth ports of the FPDDC, respectively. The small signaled state-space representation of the FPDDC has been obtained through the improved cyclic averaged current. Then, to get the receding horizon-based MPC optimal control action, ∆u * [k] ; k = 0, 1, 2, 3, . . ., the above-mentioned model of the FPDDC is discretized. The ∆u * [k] has been obtained by formulating a performance index, Ja [k] based on an error minimization between the reference AL power demand, rpd [k] and the actual AL power, y [k]. The corresponding results have been obtained through the Simulink platform of the MATLAB. Further, the article takes sequential quadratic programming (SQP) into consideration to benchmark these solutions.
Design of optimal PI controller for torque ripple minimization of SVPWM-DTC of BLDC motor
Authors: Kumar Mallempati Sunil , Satheesh Gopisetti , Peddakotla Sujatha
Published: January 2023

Conventional direct torque control (CDTC) for brushless DC motor (BLDCM) using proportional integral (PI) controller suffers from torque ripple minimization and speed regulation issues. A novel method in fusion with space vector pulse width modulation (SVPWM) with DTC using optimal PI controller is developed to minimize these issues. In this method, SVPWM replaces switching table and hysteresis controllers in CDTC. To get better performance in steady state, conventional PI controllers are preferred in SVPWM-DTC for BLDCM. However, uncertainty arises due to PI controller tuning as well as load variations. In such a case, optimal PI controller tuned properly can minimize these uncertainties. Here, JAYA algorithm is used to tune controller gain parameters. Simulations of proposed PI controller of SVPWM-DTC for BLDCM are carried away in Simulink. To appreciate the performance of proposed optimal controller of SVPWM-DTC for BLDCM, the simulation results are compared with Conventional PI controller and particle swarm optimization (PSO) technique based tuned PI controller. This proposed technique reduces the toque ripple by 63.1% when compared to conventional PI and 58.5% when compared to PSO-PI controller. It also improves the settling time by 43.9% when compared to conventional PI and 46.79% when compared to PSO-PI controller.
An advanced LVRT controlled DSCC-STATCOM for reactive power compensation
Authors: Sharma Rashmi , Makwana Vijay H.
Published: January 2023

This article focuses on the control of STATCOM for the improvement of reactive power compensation during grid faults and unbalanced load. The problem encountered with convectional voltage source converter based STATCOM for reactive power management and capacitor voltage balancing during grid faults are analyzed and its operational limitations are studied. To remove the above problems, an adaptive low voltage ride through control technique based modular double star cascaded converter (DSCC) STATCOM is proposed. In this dynamic control, the positive reactive currents and negative reactive currents are separately controlled for reactive power management and a zero (Vo) sequence voltage is inserted for the management of active power. This advanced control method effectively balances the submodule capacitor voltage within its prescribed limits by managing the equal distribution of active power between converter legs and provides dynamic reactive power management during grid faults. The effectiveness of the DSCC-STATCOM, with proposed control method is verified using MATLAB/Simulink software-based simulations under single line to ground fault and unbalanced load.
Inter-connected AC/DC HMGS power management with 3-phase and 1-phase ILC
Authors: Razzaq Syed Abdul , Jayasankar Vairavasamy
Published: January 2023

In AC/DC hybrid micro grid system (HMGS) power converters are always tested for is performance in distribution, its ability to provide accurate power sharing, transient stability and load dynamics. The existing control methods either complex or limited to achieve optimal power flow. This paper proposes a modified decentralized droop control scheme for interlinking converter (ILC) connected to interconnected AC and DC grids. A three coordinated model is proposed where AC frequency, ILC power and DC voltage are corresponding axis. The power sharing through the ILC is dependent on the AC frequency droop and DC voltage droop which occurs due to overloading. The control scheme is designed for single and three phases ILC. The obtained results are compared with double loop control method which shows less frequency deviations, accurate power sharing. The ILC performs autonomously and transfer power bidirectional under islanded mode. The simulation is carried in MATLAB/Simulink.
Design and performance analysis of asymmetric multilevel inverter with reduced switches based on SPWM
Authors: Salman Layth S. , Al-Badrani Harith
Published: January 2023

Multilevel inverters have the benefit of producing high output voltage values with little distortion. This paper deals with decreasing total harmonic distortion (THD) and providing an output voltage with various step levels switching devices. In this study, a 27-level inverter with three asymmetric H-Bridge was designed and simulated based on level shift sinusoidal pulse-width modulation and phase shift sinusoidal pulse-width modulation methods. MATLAB/Simulink has been used to create this model and test it at different types of loads. The results showed that a multilevel inverter with (PS-PWM) produces less (THD) than a multilevel with (LS-PWM), when the resistive load was used, the produced voltage and current THD in (PS-PWM) and (LS-PWM) are 3.02% and 4.30% respectively, that has resulted from the linearity between voltage and current in the resistive load. While in the case of applying an inductive load, the THD in the voltage is constant in both (PS-PWM) and (LS-PWM) methods and has the same values as the THD in a resistive load. However, the THD in the current with inductive load decreased to 2.79% in (PS-PWM) and 4.04% in (LS-PWM). Finally, these results show that the performance of the proposed power circuit with PS-PWM is better than (LS-PWM).
Mitigation of harmonic distortions in third rail electrical systems
Authors: Hoo Dick Sang , Chua Kein Huat , Lim Yun Seng , Lim Boon Han , Bonab Mohammad Babrdel , Wang Li
Published: January 2023

The extensive use of power electronic converters in the third rail system increases the harmonic distortions on the rail electrical feeding systems. Electrical machines and transformers could be overheated causing premature failures of the devices. It is therefore important to address the harmonic distortions on the electrical networks during real-time operation, which includes the degraded operation, not just the normal operation. In this paper, the harmonic distortions of a third rail system are investigated using electrical transient and analysis program (ETAP) simulation software. Four operating scenarios, namely the normal operation and three degraded operations, are considered in the studies. The degraded operations occur when one of the bulk supply transformers or 33 kV feeders is out of service. The findings of the studies showed that the 11th and 13th order harmonics are the dominant harmonic orders due to the use of 12-pulse rectifiers on the third rail system. Single-tuned harmonic filters are designed and placed in the 33 kV feeders to mitigate the individual voltage harmonic distortion (IHDv) and the total voltage harmonic distortion (THDv) so that it is within the statutory of IEEE 519:2014.
Self-excited asynchronous generator with PV array in detained autonomous generation systems
Authors: Nagarajan Karthikeyan , David Anbarasi Jebaselvi Gnanaiah
Published: January 2023

It's important to examine and handle the issue of green energy generation in inaccessible locations. Nonrenewable hybrid power has environmental and economic impacts. Reliable electricity and energy efficiency are priorities. Renewable energy that is eco-friendly and doesn't affect the environment. Solar and wind power, two ecologically benign and load-sharing-capable forms of renewable energy, are included in this technique. At the same time, solar power will keep the load voltage balanced and the system stable thanks to the inclusion of a DC-DC converter. The asynchronous generator has been selected because of its low maintenance needs and extended service life; nevertheless, the voltage on the load side is unbalanced when this machine is in operation. An asynchronous generator can be a viable alternative to well-developed synchronous generators for use in wind turbines or small hydro generators because they have relatively inexpensive costs, are simple, require inadequate maintenance, possess adequate resistance to wear and tear, and have reduced overload damage. It is difficult to maintain a continuous supply of energy in faraway regions because of the lack of related work in the power distribution networks. This problem is addressed in this paper by a well-designed converter that maintains a constant output voltage.
Power quality enhancement of grid-connected PV system
Authors: Mishra Debani Prasad , Rout Kshirod Kumar , Mishra Sivkumar , Nivas Mandakurit , Naidu Rambilli Krishna Prasad Rao , Salkuti Surender Reddy
Published: January 2023

Solar photovoltaic (PV) power, for its multiple benefits, has adhered to prominent consideration in the electrical energy generation region. The double-stage triple-phase grid-connected solar PV (SPV) system is utilized to enhance the power quality by employing a lymphoblastoid cell lines LCL filter. In this method, a DC-DC converter and DC-AC converter make a feasible juncture of the PV systems to the electrical interface. For converting boosted DC into AC, A 3-phase DC-AC converter is used, which is supplied into the grid. A 3-phase voltage converter is employed in place of an inverter for interfacing amid the voltage generated by the PV system and the grid possessing an AC transmission line. An maximum power point tracking (MPPT) application is used in this proposal to amplify the effectiveness of the PV array in face of any unsteady climatic circumstances. Hence, the highest energy could be secured out of the solar PV array and interfaced with the grid. Enhancing power quality by employing an LCL filter is quantified by FFT analysis in MATLAB. The advised proposal has attained a very low total harmonic distortion (THD), proving its efficacy. Also, the outcomes ascertain the applications of the proposed system and extend future advances of renewable energy with a great power quality improvement.
A robust fuzzy logic PI controller for solar system battery charging
Authors: Zerouali Mohammed , Ougli Abdelghani El , Tidhaf Belkassem
Published: January 2023

This article discusses a design of a photovoltaic (PV) system that allow charging a battery under variable climatic circumstances. The system under study is composed of two DC-DC converters a boost and Buck converter. The first one is used to extract the maximum power from the PV array through a novel variable step size P&O based MPPT offering a high tracking accuracy compared to classical approaches such PO and INC. The second converters aim at regulating the output voltage and current that feeds the battery using a robust optimal PI (O-PI) which has a faster time response and high accuracy compared to classical PI and PID controllers. The overall system and thecontrol strategies are tested and validated in MATLAB/Simulink environment. The simulations results show the effectiveness and the robustness of the system.
Simplified control system for grid-tied modular multilevel based energy storage
Authors: Dobroskok Nikita , Lavrinovskiy Viktor S. , Trusova Ekaterina S.
Published: January 2023

Microgrids and networks with renewable energy sources are increasingly common. A network energy storage device is required for their normal operation. Common high-voltage storage devices have many disadvantages. It may create a risk of fire or electric shock if it is not handled carefully. It is not possible to utilize used batteries both safely and effectively at the same time. Using a small number of levels negatively effects on output voltage curve quality. Large assemblies already may be divided into smaller ones to be serviced and replaced independently. The article proposes an approach to development for an energy storage system not with a concentrated, but with a distributed battery where small battery assemblies are placed in the separate cell DC-link of a modular multilevel converter. A solution is also proposed that ensures the sensors minimization to ensure the possibility of accumulation and return of energy to the network.
Using PSO algorithm for power flow management enhancement in PV-battery grid systems
Authors: Abdelkaderis Benslimane , Merabti Abdelhak , Yamina Benslimane
Published: January 2023

In this article, we have shown the possibility of improving the quality of the energy injected into the electrical network and the flexibility of its exchange between the different components of the proposed hybrid network (photovoltaic generator connected to the network-storage battery-load of the DC motor) to develop a control element based on the combination of fuzzy logic and an algorithm derived from PSO Animal Behavior. The proposed control works on DC/AC and bi-directional DC/DC converters, which form the basis of power management between the parts of the proposed hybrid network. MATLAB/Simulink software is used to demonstrate the effectiveness of the proposed control. The results show that the proposed control contributed to the stability of the photovoltaic energy produced, the improvement of the quality of energy injected into the network, as well as the response speed during the process of charging and discharging the battery, which gave more efficiency to the DC motor connected to the DC bus.
An efficient hybrid biomechanical energy harvesting system using human motions for low-power applications
Authors: Venugopal Mohankumar , Jayaramaiah Govindanayakanapalya Venkatagiriyappa
Published: January 2023

The biomechanical energy harvesting system (BM-EHS) uses human daily activities to create electricity. The BM-EHS is one of the potential alternative technologies for powering wearable and implantable electronic gadgets without batteries. The hybrid BH-EHS is modeled using two different vibration source-based human activities in this manuscript. The piezoelectric (PE) and electromagnetic (EM) based EHS are combined in the hybrid BM-EHS. The PE- EHS is based on human walking and jagging motions and is represented using a mass-spring-damper system and PE stack. The EM- EHS is based on the human knee and hip motions, with shaft conversion and a DC motor. The PE, EM, and hybrid BM-based EHS are modeled using MATLAB/Simulink, and performance results are realized individually. The PE-EHS obtains the average output voltage of 0.5 V and harvests 53.18 mW of power. Similarly, the EM-EHS achieves the average load voltage of 0.567 V and 30.6 mW harvested power. The hybrid BM-EHS obtains the average load voltage of 0.79 V and harvests 86 mW of power. The proposed BM-EHS is compared with the existing EHS with better-harvested power and energy improvement for the given load conditions. Overall, the harvested power can power up the low-power applications.
Performance analysis of voltage sensorless based controller for two-stage grid-connected solar PV system
Authors: Morey Meghraj , Gupta Nitin , Garg Man Mohan , Kumar Ajay
Published: January 2023

In this research, a sensor free DC-link voltage controller based multifunctional inverter is proposed for a two-stage three-phase grid-connected solar photovoltaic (PV) system. First, the proposed scheme consists of an outer voltage controller requiring DC-link voltage knowledge, has the ability to manage power-sharing between the PV system and the utility grid, and second, has the ability of the VSI to act as a compensator for harmonics in the grid current polluted by non-linear loads. The suggested active power controlling grid reference current signal scheme replaces the standard controller, requiring the high voltage sensor to sense DC-link voltage, which is pricey, increasing the hardware complexity and reducing reliability. The performance of the proposed active power management approach is comparable to that of a conventional voltage sensor-based voltage controller. The effectiveness of the proposed method for two stage three-phase grid-connected solar PV system under fixed and variable irradiance feeding nonlinear loads is rigorously verified using MATLAB/Simulink software.
Design and control of DFIG with SMES storage under symmetrical grid fault
Authors: Riouch Tariq , Nichita Cristian
Published: January 2023

This paper presents a novel design and robust control for wind conversion systems using DFIG. The system is designed to reduce the problems related to the sudden variation of the wind speed and to improve the sensitivity of the DFIG to grid faults to avoid disconnection of the wind system from the electrical grid. To enhance the DFIG behavior, power fluctuation and to protect power devices under symmetrical faults, a specific superconducting magnetic energy storage (SMES) scheme and its control are proposed. To validate this study, the control structure and strategies were implemented in the MATLAB/Simulink environment. The results obtained by simulation were compared with those using traditional control strategies, they highlight an improvement in the functioning of wind conversion systems of this type, showing the rigor and effectiveness of the proposed strategy.
Wind and solar energy potential in Herkalou and Lake Assal locations, Djibouti
Authors: Idriss Abdoulkader Ibrahim , Ahmed Ramadan Ali , Omar Abdou Idris , Atteyeh Hamda Abdi , Ibrahim Mohamed Houmed , Akinci Tahir Cetin
Published: January 2023

The absence of meteorological data to identify the energy resources and the available energy potential represented a major obstacle in some areas in Djibouti. To solve this data problem, in this paper, wind and solar potential were assessed by collecting daily and monthly wind and solar data for the period from 1 January to 31 December 2020, for Herkalou and Lake Assal site. This study highlights that the wind resources in the Lake Assal location are falling into class 7 with high wind speed value of 16 m.s-1 and the wind energy reaching1700 kWh/m2 at 100 m height above ground level. While the Herkalou site shows a lower potential with value of 7.5 m.s-1 and 160 kWh/m2. The solar potential shows a similar distribution and a constantly high level of solar radiation throughout the year, with the monthly maximum global radiation peaks of around 900 W/m² between 11.00 and 14.00 pm for both sites. The highest monthly average of global solar irradiation values was 5.29 kWh/m2 day-1 and 6.90 kWh/m2 day-1 in March for Herkalou and Lake Assal, respectively. Results obtained in this study are favorable to deploying the solar and wind technologies for the studied sites.
Analysis of total harmonic distortion in single-phase single-stage grid-connected photovoltaic system
Authors: Anang Nurhazwani , Muda Wan Mariam Wan
Published: January 2023

This study presents the power quality issue mainly focus the effect of total harmonic distortion (THD) on a grid-connected PV system. Firstly, a grid-connected PV system with a single-phase single-stage has been developed to monitor the output values of voltage and current and also its harmonic distortion behaviours. Maximum power point tracking (MPPT) was implemented since it is proven as the first step for THD reduction because MPPT will extract maximum output power, voltage, and current of the PV system without fluctuation which leads to a low THD level. Furthermore, the employment of a good filter also reduces the THD level in a PV system. Thus, this study will focus on the THD analysis to resolve the power quality problems in the grid-connected PV system. The result shows that the THD value for current, ITHD analysis is more significant than the THD value for voltage, VTHD analysis in the case of grid-connected PV systems operating under different solar irradiances. In a conclusion, the increase in solar irradiance will increase the rated values of generated power and current thus, increasing the performance of THD values.
An intelligent energy management system for optimum design and real-time operation
Authors: Zedak Chaimae , Belfqih Abdelaziz , Boukherouaa Jamal , El Mariami Faissal
Published: January 2023

Planning and management of distribution networks has become a very difficult task, especially with the strong expansion of renewable energy sources (RES) which are intermittent in nature. Maintaining fluidity and reliability of real-time decisions while taking into consideration uncertainties related to production and increasing the profit of distribution network operators is the objective of the system proposed in this work. It is an intelligent energy management system dedicated to the management of grid-integrated RES and battery energy storage systems (BESS), composed of: i) a real-time control and data acquisition model, ii) a model for forecasting the intermittent parameters of RES based on neural networks, iii) a long-term planning model based on the optimal placement and size of RES and BESS, and iv) an hourly planning model for scheduling the energy distribution between energy sources. The non-dominated sorting genetic algorithm and the entropy-TOPSIS method (technique for order of preference by similarity to ideal solution) form the basic block of this model. To evaluate it, a modified IEEE 33 bus network was used for testing and the results, for short-term scheduling, proved that the system succeeds in maximizing profits and significantly minimizing CO2 emissions, in addition to power losses and voltage drops.
Global solar radiation forecast using an ensemble learning approach
Authors: Mishra Debani Prasad , Jena Subhrajit , Senapati Rudranarayan , Panigrahi Atman , Salkuti Surender Reddy
Published: January 2023

With the increase in demand for solar power, a solar power forecasting model is of maximum importance to allow a higher level of integration of non-conventional energy into the existing electricity grid. With the advancement in data availability, there’s a good time to use data-driven algorithms for enhanced prediction of solar energy generation. Gathering and analyzing data can predict solar energy generation and mitigate the impact of solar intermittency. During this research, we explore automatically creating prediction models that are site-specific utilizing machine learning to generate solar radiation from meteorological station weather forecast reports, and from the predicted solar radiation corresponding solar power output can be calculated depending upon the characteristics of the solar PV system used. The challenge is to enhance the accuracy of the forecast. Ensemble techniques like random forest (RF) and extreme gradient boosting (XGBoost) are well suited for solar radiation prediction as they improve stability as well as combine several machine learning models to reduce variation and bias which outperforms the majority of models, as a result making them a perfect model in the field of solar energy prediction.
Analysis of linear motor with symmetrical EMF vector for household elevator application
Authors: Zuki Nor Aishah Md , Othman Raja Nor Firdaus Kashfi Raja , Shukor Fairul Azhar Abdul , Ahmad Suhairi Rizuan Che
Published: January 2023

Linear permanent magnet synchronous motor (LPMSM) has emerged as a viable alternative to other linear motors for higher thrust lifting action. With the advancement of permanent magnets, LPMSM could contribute to energy conversation while also being suitable for applications requiring higher thrust, such as elevator. However, because the existing LPMSM is larger in size, it requires more space to be equipped with a household elevator. To address this issue, a new LPMSM with increased thrust capability has been proposed. The new LPMSM is modelled and analyzed in terms of back EMF and force in this paper. For improved performance, a symmetrical EMF vector is applied to the new LPMSM. In terms of back EMF and force, 4 LPMSM models are studied. According to the results, 6 slot 4 pole has the highest back EMF when compared to the others. As a suitable combination of slot and pole, a symmetrical EMF vector is the suggested LPMSM at the end of this research.  
Modified PDPWM control with MPPT algorithm for equal power sharing in cascaded multilevel inverter for standalone PV system under partial shading
Authors: Yahya Mawadah Glaa , Yahya Massara Glaa
Published: January 2023

In this paper, a modified particle swarm optimization (MPSO) based maximum power point tracking (MPPT) controller is used to track the maximum power of a PV system using DC-DC boost converter technology. To raise the PV module's input DC voltage, a DC-DC boost converter was employed. The boost converter powered the DC-AC multilevel PWM inverter, which then delivered the output AC voltage to a solitary inductive load. Cascaded multilevel inverters are often used to condition power in renewable energy applications because they are easy to use and have few parts. Ripples in the voltage of DC link capacitors cause low order harmonics and inter harmonics in the multilevel inverter's output voltage. Phase disposition pulse width modulation (PDPWM) has the fewest harmonics. The inverter cells' power delivery is not equal in this manner. In the present paper, a strategy for improving sharing of power PDPWM for photovoltaic applications is proposed. The modified PDPWM is used on a 9-level inverter where each cell is connected to a PV array running at maximum power point tracking MPPT and under partial shadowing for single phase multilevel inverters. The MATLAB/SIMULINK software was used to do simulations, and the findings demonstrate that the method presented is effective at balancing the way power is shared between different inverter cells and reducing the voltage ripple of the DC link capacitor.
Cleaning frequency of the solar PV power plant for maximum energy harvesting and financial profit
Authors: Said Mohamed R. , El-Samahy Adel A. , El Zoghby Helmy M.
Published: January 2023

Cleaning frequency of the solar PV power system plays a major role in energy harvesting. This paper proposed an optimized cleaning frequency for the PV power plants. The objective is to maximize energy harvesting and increase financial profit. The proposed technique is tested in roof top grid connected 20 kW PV power plant in Cairo, Egypt. Experimental results are collected for one year throw the period from January 2021 to December 2021 based on real time monitoring under the regular cleaning of the PV plant every fifteen days. The collected data and results are used for deriving a formula to find the optimal frequency for cleaning the PV cells. This formula can be used for any PV power plant under different operating conditions. Therefore, the formula can detect the financial losses due to the dust accumulated on the surfaces of PV panels. The model proposed in this research is verified by the comparison between the generated power from the photovoltaic power plant and the cost of cleaning (water and cleaning workers) in case of manual cleaning, taking into consideration the various operating conditions though whole the period of the study.
Fuzzy logic controller of photovoltaic panel-unified power quality conditioner with voltage compensation and stability
Authors: Tounsi Mahmoud Mostefa , Meliani Bouziane , Benaired Noreddine , Djaafar Fatiha
Published: January 2023

The intensive use of non-linear loads is further contributing in the increase of power quality problems. They cause voltage distortions and current harmonics in an electrical distribution network. To minimize these problems, the unified power quality conditioner (UPQC) is used. The intermediate circuit voltage of this filter can deviate from its source during a transient event during a harmonic disturbance in voltage (voltage dip) or in current during the connection and disconnection of polluting loads. In a particular point in operating time, the stabilization of dc-bus and the compensation ability is necessary to maintain around its reference. The combination of a UPQC conditioner with a photovoltaic (PV) system connected to the intermediate element of the two converters of the DC bus (DC Link) is the adequate solution. The photovoltaic (PV) system is fitted with a fuzzy MPPT controller regulated by an algorithm (P and O) to control a boost converter. This converter is controlled by fuzzy logic related to the capacitor terminal of UPQC. The simulation results show that the UPQC conditioner based on the proposed photovoltaic system can be used for voltage disturbance compensation and the protection of non-linear loads connected to a distribution network.
Electric vehicles based electric power grid support: a review
Authors: Rabie Afaf , Ghanem Abdelhady , Kaddah Sahar S. , El-Saadawi Magdi M.
Published: January 2023

Grid connected electric vehicles (EVs) can provide energy quality services to ease intermittent renewable energy sources dependent, enhance grid stability performance, reliability and load balancing in the power system. Moreover, incorporating sufficient EVs into the power grid will assist reduce greenhouse gases. However, the unrestrained EVs charging impact the raise of peak request, frequency deflection, voltage instability, power quality from the acceptable limits. It can also cause overloading of the power system equipment and an increase in power losses. In this paper, the influences EV technologies on various energy systems, control scheme strategy, benefits, and motivational challenges are investigated. An overview of the impacts of uncontrolled EV loading on the electric power system and how controlled charging becomes benefit impacts is presented. Moreover, a review of the controlled charge and discharge benefits of EVs and the electrical serving involved in reduction of frequency deviation, voltage stability, power quality improvement is introduced. This review shows that integration of optimal control of EVs with a suitable optimization technique can improve and provide on time multi ancillary services of EV integrated with weak grid. In addition, this review provides research tracks which can be followed by researchers.
Nonlinear control of an induction motor taking into account saturation and rotor resistance variation effects
Authors: Es-Semyhy Mustapha , Ba-Razzouk Abdellfattah , El Haroussi Mustapha , Madark Mhamed
Published: January 2023

Nowadays, electrical drives require more and more precision and reliability. Induction machine is one of the most robust actuators in terms of maintenance and reliability. Their control requires a good knowledge of the physical phenomena governing its operation. Saturation and heating are two main phenomena that must be taken into account to achieve the desired performance. In this paper, we will synthesize a nonlinear control law based on the “Backstepping” method, to regulate rotor speed and flux. This law takes into account saturation and rotor resistance variation effects. The immunity of the control to temperature rise will be tested. This control strategy is studied by simulation in the MATLAB/Simulink environment.
Experimental study of the VFD's speed stabilization processes under torque disturbances
Authors: Kodkin Vladimir L. , Anikin Aleksandr S.
Published: January 2023

Maintaining speed with various jumps and changes in load torque is one of the main tasks of variable frequency drives (VFD). The article considers the operation of the VFD under the influence of periodic perturbations of variable frequency and amplitude. The dependence of the transient function of the VFD and the family of frequency characteristics associated with it on the frequency of the stator voltage and slip underlies the methodology for experimental studies of such drives. The traditional method is based on the response to harmonic stimulation and works well for a non-linear system. In the course of the work, it was found that the introduction of dynamic positive feedback (DPF) allows to compensate for disturbances of varying frequency and amplitude. Experiments with a sinusoidal change in the load torque have shown the effectiveness of introducing the DPF in front of conventional sensorless control systems (vector and scalar).
New independent control of a Bi Machine system powered by a multi-leg inverter applied to four in-wheel motor drive electric vehicle
Authors: Adda Benkhalfallah , Kada Hartani , Aouadj Norediene , Belhia Karim Abdelkader
Published: January 2023

The four-wheel-drive electric vehicle's traction chain is powered by four permanent-magnet synchronous motors (PMSM), powered by a single three-phase, five-leg inverter (FLI). In order to achieve the behavior of a mechanical differential and to require the parallel wheel-motors to turn at identical or different speeds, using this structure, an independent control is applied on each driving wheel. For this particular structure, there is a shared inverter leg between the two phases of two machines. The other two phases of each machine are attached to their own two inverter legs. This work's main focus is the suggestion of a new DTC technique for the control of an electric vehicle (EV) with two set bi-PMSM motor-wheels fed in parallel by a single three-phase five-leg inverter. The simulation results show that this new control technique can ensure excellent dynamics of the electric vehicle driving system.
Calculation of temperature data from an automatic solar heat supply system
Authors: Kunelbayev Murat , Ixanov Serik , Imanbek Baglan , Omarov Rashit , Dauren Omar
Published: January 2023

This paper calculates the temperature in an automated solar heat supply system. The study used an automatic controller to monitor the temperature data of the entire system. The developed solar heat supply system has a flat solar collector, heat-insulating translucent glass, and double glazing with reduced pressure. The coolant is made of thin-walled corrugated stainless pipe. The heat from the solar flow heats the liquid removed from the collector, and cold water from the siphon enters its place. There is a constant circulation of heat, which increases heat transfer efficiency by eliminating additional partitions between the panel and thermal insulation. The controller has sensors that register using field-programmable gate array (FPGA) STM32, designed to monitor the entire solar system, and the actuators include power relays. During the experiment, it was found that temperature sensors save energy by 2% due to the use of power relays, which has a significant impact on the service life of the equipment.
ANFIS MPPT with power management strategy to harvest reliable power from standalone PV systems to residential loads
Authors: Alagammal Subbaraman , Bhavani Ramachandran , Bhavani Ramachandran , Muhaidheen Mohammed , Muhaidheen Mohammed
Published: January 2023

In recent decades, the matching between the growing energy demand and generation is becoming the challenging task to the researcher’s leads for the development of standalone solar photo voltaic (SSPV) power system. The SSPV system is more suited for electrification of essential loads uses DC power as it offers high efficiency. This work aims to model and simulate SSPV with lead acid battery is used as a DC source. The proposed series shunt charge controller with power management strategy (PMS)is designed and modeled to control the power flow among SSPV, battery and the load. adaptive neuro fuzzy inference system (ANFIS) controller effectively regulates the output voltage by controlling duty ratio of the suitable converter for driving a DC load. A PMS is developed for selecting the operating mode of SSCC by sensing and regulating the battery voltage within 11.6-12.95 V. Here, the 250 Wp panel has been employed to charge a 12 V, 34 AH battery. The practicability of SSPVB system is verified under various loaded conditions using MATLAB/Simulink for a period of 24 hours. A simulation result proves that this SSPV Battery system is capable to electrify the essential loads in rural and isolated areas and also reduce the dependency of grid power.
Memoryless radial basis function neural network based proportional integral controller for PMSM drives
Authors: Hossain Md. Alamgir , Shahjahan Md.
Published: January 2023

This research paper presents the memoryless radial basis function neural network (RBFNN) dependent proportional integral (PI) controller for permanent magnet synchronous motor (PMSM) drives. The proposed RBFNN is memoryless adaptation scheme since the algorithm neither use the past samples nor retain the previous adaptation direction and hence the observations are used only once. Firstly, mathematical model for PMSM drive is explained and then structure of RBFNN controller is formulated. RBFNN consists of single input, a hidden layer with five neurons, a single output layer that are used to track the speed of the machine. The Jacobian matrix obtained from RBFNN is used to adjust the gain of the speed and applied to PI controller. The performance of the PI based vector controller with and without RBFNN are compared through the simulation by using MATLAB/Simulink environment. The simulations show that the proposed RBFNN outperform the existing PI based control method and enhances the speed tracking of PMSM drives.
Living with the Virus: Graduate School Students Evaluation of Stressors Related to the Pandemic
Authors: Geronimo Jessica Frey Shane S. , Morada Charmaine M. , Reyes Joseph Niño A. , Zapanta-Ribu Mary Shaira Christa , Vigonte Florinda G. , Malang Bernandino P. , Abante Marmelo V.
Published: January 2023

The Coronavirus Disease (COVID-19) becomes a global threat in March of 2020. Several countries were on lockdown. It affects health and results in post-traumatic stress disorder (PTSD). During the quarantine and lockdown, the lack of freedom resulted to psychological consequences. In the Philippines, it was March 15, 2020 when the initial COVID-19 was instituted commonly recalled due to lockdown and canceled classes. Filipinos in general and students in particular were worried of their health information including vaccine availability, efficacy, and infection rates. Mental health is impaired by pandemic risks. UNICEF Philippines, then, advocated alternative and continuing learning.  The major purpose of this research is to determine graduate students' levels of stress during the COVID-19 outbreak. The descriptive-correlational design was used for the quantitative investigation. The 150 responders are selected at random from Metro Manila master's degree students in the academic year 2022-2023. The adopted questionnaire consists of seven items that are multidimensional scales with psychometric qualities. Using chi-square, the findings revealed that, among demographic profiles, only age showed a significant relationship with the association of global stress. Thus, it can be stated that age is a crucial factor in assessing the global stress of graduate students. COVID-19 is more contagious in adults, reflecting their anxiety and stress during the epidemic.
Desafíos de la docencia indígena en pandemia: reflexiones a partir de una encuesta virtual en 2020
Authors: Hecht Ana Carolina
Published: January 2023

La pandemia del COVID-19 impacto en la vida cotidiana de todo el mundo, modificando las rutinas y quehaceres e imponiendo el aislamiento social como medida preventiva. Una de las medidas más significativas fue el cierre de las escuelas, para el paso de la educación presencial a la virtualidad. En ese marco, este artículo se propone, por un lado, reflexionar sobre los desafíos que la etnografía debe asumir frente al aislamiento y las nuevas herramientas metodológicas que se requieren para vincularnos con nuestros referentes empíricos. Por otro lado, presentar la adaptación de una estrategia metodológica (la encuesta) a un entorno digital. Esta encuesta tiene como objetivo dar cuenta de las experiencias de enseñanza de la lengua toba/qom en el marco de la Educación Intercultural Bilingüe en la provincia del Chaco (Argentina). Este texto presenta tanto las decisiones metodológicas implícitas al diseño de esta encuesta, como algunos de los resultados obtenidos sobre enseñanza de la lengua indígena y el quehacer docente en pandemia.
Uma distinção imprecisa: Anti-Judaísmo e anti-Semitismo (Um excerto de Le Judaisme et ses Juifs)
Authors: Favret-Saada Jeanne , Flaksman Clara
Published: January 2023

Contribuições acadêmicas sobre a responsabilidade das Igrejas no extermínio dos Judeus durante a Segunda Guerra Mundial contrastam o “anti-Semitismo” Nazista (a aversão pelos Judeus como um grupo racial) com o “anti-Judaísmo” Cristão (a aversão cristã pela religião judaica), da mesma forma que poderíamos opor o novo ao antigo, o moderno ao tradicional, o político ao religioso, ciência à tecnologia. A autora mostra, usando quatro exemplos (León Poliakov, Hannah Arendt, Colette Guillaumin, Thomas Nipperdey & Reinhard Rürup), que essa discussão nos leva a ignorar as ações das igrejas no processo que levou da invenção do termo anti-Semita em 1879 à destruição dos Judeus pelos Nazistas.
Seasonal temperature and precipitation regimes drive variation in the wood of oak species (Quercus) along a climatic gradient in western Mexico
Authors: Arenas-Navarro Maribel , Oyama Ken , García-Oliva Felipe , Torres-Miranda Andrés , Terrazas Teresa
Published: January 2023

To achieve optimal balance among wood’s support, storage, and transport functions, tree species present adaptive variation in wood anatomical traits. Oaks (Quercus) are woody plants that are dominant in many ecosystems, possess wide variation in wood traits, and can tolerate water stress in diverse habitats. Mountain regions contain steep climatic gradients that exert strong environmental pressures on wood traits. The aims of this study were: (1) to quantify the anatomical variation in 21 oak species distributed along an environmental gradient and (2) to analyze the interspecific variation among the studied species. Fibres and parenchyma fractions were the most abundant cell types. We found a trade-off between total fibre fraction and total parenchyma fraction modulated by the precipitation during the warmest quarter in which oak species in drier areas invested more in support cells. The 21 oak species studied showed vasicentric tracheids, which could be essential to compensate for the transport system in drier areas. Wood density was negatively correlated with the axial parenchyma fraction and fibre lumen width. Oak species have high interspecific variation in the total vessel fraction and vessel diameter. Anatomical variation in oak species along a climatic gradient showed a broad continuum of fibre characteristics from wide to narrow wall and lumen, abundant to scarce parenchyma, and wide to narrow vessels. These variations imply a diversification of ecological strategies within the genus that includes the vascular design of the stem to define the tolerance and competitiveness of the oak species.
Influences of Urbanization on an Afternoon Heavy Rainfall Event over the Yangtze River Delta Region
Authors: Jiang Xiaoling , Zhang Da-Lin , Luo Yali
Published: January 2023

An afternoon heavy rainfall event occurred over coastal Nantong, an area of 70–100 km downstream from the Shanghai–Suzhou–Wuxi–Changzhou city belt over the Yangtze River Delta, under the influences of weak southwesterly monsoonal flows and lake/sea breezes on 26 July 2018. An observational analysis shows the emergence of pronounced urban heat island (UHI) effects along the city belt during the late morning hours. A series of nested-grid cloud-permitting model simulations with the finest grid spacing of 1 km are performed to examine the impacts of urbanization on convection initiation (CI) and the subsequent heavy rainfall event. Results reveal the generation of lake breezes and warm anomalies in the planetary boundary layer along the city belt and low-level convergence, thereby inducing upward motion for CI. The southwesterly flows of the monsoonal warm–moist air, enhanced by the UHI effects along the city belt, allow the development of convective cells along the city belt, some of which merge with convective clusters during their downstream propagation, and the ultimate generation of several distinct heavy rainfall centers by local convective clusters over coastal Nantong where atmospheric columns are more moist and potentially unstable under the influences of sea breezes. Sensitivity simulations show small contribution of Nantong’s UHI effects to the heavy rainfall event. The above findings help elucidate how the UHI effects could assist the CI in a weak-gradient environment, and explain why urbanization can contribute to increased downwind mean and extreme precipitation under the influences of favorable regional forcing conditions.

Significance Statement

The urban heat island (UHI) effects tend to produce more rainfall on its downwind side than that on the other sides, but alone could hardly account for the generation of heavy rainfall. This study examines the influences of the UHI effects associated with a city belt over the Yangtze River Delta on generating an afternoon heavy rainfall event over coastal Nantong that is 70–100 km downwind from the city belt. Results show (i) the downwind advection of the UHI effects; (ii) the initiation of convective storms along the city belt, and their subsequent downstream propagation, leading to the generation of heavy rainfall over Nantong; and (iii) an important role of sea breezes in generating the heavy rainfall event.
Association of Coronary Artery Severity and Late In-Stent Restenosis: An Angiographic Imaging Study
Authors: Oguz Mustafa , Akbulut Tayyar , Saylik Faysal , Sipal Abdulcabbar , Erdal Emrah
Published: January 2023

Coronary in-stent restenosis (ISR) remains a challenge in interventional cardiology. We investigated the relationship between angiographic pre-interventional grade of lesion stenosis (LS) and the prognosis of late ISR. After exclusions, 110 patients with ISR and 109 patients without ISR were compared. In the ISR group, the grade of LS was greater ( P < .001) and the length of the critical segment (LCS) was longer ( P < .001). Stent length was longer in the ISR group ( P = .008). Compared with the LCS, the grade of LS above 87.5% is 6.9 times more predictive of ISR than the LCS >10.5 mm. Kaplan–Meier curve analysis showed that the grade of initial LS >87.5% had a higher ISR rate than the grade of LS <87.5% (log-rank test P < .001) and critical lesion length over 10.5 mm had a higher ISR rate than critical lesion length under 10.5 mm (log-rank test P < .001). The present study found that the angiographic pre-interventional grades of LS and LCS were important predictors of ISR. Pre-interventional angiographic stenosis >87.5% was significantly predictive of late ISR.