Simulink Application Research Articles

Numerical modeling of electrical parameters of LiFePO4 batteries

The object of research is the physical processes of electric energy storage in Li-ion batteries. The problem being solved in the work is related to the lack of reliable mathematical models of storage batteries, which leads to the appearance of undesirable effects or emergency situations when changing operating modes. In the course of the work, Li-ion battery models based on electrochemical theory and electrical circuits were considered. The six most common equivalent battery replacement schemes are presented. The advantages and disadvantages of the considered substitution schemes are given. The dual-polarization mathematical model was found to most accurately describe the performance of the battery at the end of the discharge and charge cycles compared to the first-order Thevenin model, the RC model, and the active resistance battery model. The physical processes in the storage battery during pulse discharge, which is the main part of electrical energy storage systems based on electrochemical technology, were studied. Mathematical modeling was carried out in the Matlab software package using the Simulink application program package. The dependence of the parameters of the equivalent lithium-ion battery replacement scheme according to the second-order Thevenin model on the ambient temperature and state of charge is considered. It was established that the value of EMF E depends more on the change in SOC than on temperature. In turn, the active resistance ROM shows a greater dependence on temperature than on the change in SOC. At high temperatures, the resistance value decreases. The parameters R1 and C1 characterizing the electrochemical polarization vary in the range from 10 to 75 % SOC. The parameters R2 and C2, which depend on the concentration polarization, vary in the intervals from 0 to 25 % SOC and 75 to 100 % SOC. The recommendations for choosing a Li-ion battery model developed in the work can be used in practice. The established dependencies will help to better design electrical energy storage systems based on electrochemical technology.

MATLAB® Modeling of a Microgrid: Towards a Vision Based on Entropy Balance

A microgrid is defined as the link of consumer loads and decentralized energy assets with the ability to control the entire system as a whole. The modeling of an electromagnetic microgrid is discussed in this work to analyze energy effectiveness and entropy balance. The method computes the associated losses and simulates the electrical behavior of the components. The model is built and tested by using the MATLAB Simulink application. The system is made up of several blocks consisting of solar panels, batteries, consumer loads, and the inverter needed to connect them all. Their energy efficiency is assessed using the findings from each of these components. The system's entropy generation is also calculated to study how it relates to performance.

MODELING OF AN AUTOMATIC CONTROL SYSTEM FOR SUBMERSIBLE PUMPS IN DRAINAGE WELLS IN THE MATLAB SOFTWARE ENVIRONMENT

The accumulation of moisture due to summer showers or due to sudden melting of snow can lead to deformation of the foundation of buildings, the appearance of cracks and deflections on it, as well as the release of harmful substances into the environment. Drainage systems, especially in urban infrastructure, play an important role in effectively treating wastewater and maintaining groundwater levels at safe levels. Automatic control of submersible pumps in such systems is critical to optimizing the drainage process and minimizing flood risks. This article develops a model of an automatic control system for submersible pumps in drainage wells, which includes components such as a drainage well, a drainage pipeline valve actuator, a pump and a level sensor. The model was created in the MatLab software environment using the Simulink application package, which made it possible to simulate and analyze the process of water entering a water collection well and its pumping out using a pump, as well as to study in detail how individual blocks of the system react to incoming water. The results of this work can be useful for engineers and designers working in the field of hydraulic engineering. They can use the model to optimize control systems and to predict and analyze the performance of drainage systems.

IMPLEMENTATION OF AN ECONOMICAL IoT-BASED LIQUID TANK CONTROL SYSTEM TO SUPPORT ONLINE PROCESS CONTROL PRACTICUM

Due to the pandemic era, many courses in higher education were conducted online to minimize the risk of disease transmission. For several engineering courses that contain practical material, an appropriate method is required to deliver practicum learning materials online to maintain the quality of these courses. Therefore, in this paper, the implementation of an economical IoT-based (Internet of Things) liquid tank control system was introduced to support the online practicum class. The tank system design has a height of 120 cm and a diameter of 50 cm. The tank features a valve, flowmeter, and an 18 LPM water pump. The control systems, consisting of Arduino Uno, an ultrasonic sensor, and a stepper motor, was run on the MATLAB Simulink application. IoT systems can be deployed using the TeamViewer app. After running the simulation, it was found that the lower setpoint change did not make significant changes in the process and produced the same curve shape as the steady state. The curves at steady state and during processing are not much different for the disturbance change. The error can be calculated using IAE and ITAE. The performances of the control system with IAE and ITAE values are 1.460 and 915.122 for setpoint change, respectively. For disturbance change, the IAE and ITAE values are 0.877 and 490.446, respectively. This system can help students better understand the industry 4.0 concept and allow them do practical work effectively from home at a low cost.

Development and simulation of the Feed Pusher Robot software and hardware system for the maintenance of the feed table at livestock facilities

BACKGROUND: Analysis of trends in the development of industrial technologies in the field of agriculture showed that manufacturers of technological equipment used on farms turn to robotics to exclude human labor when performing labor-intensive cyclical operations that are accompanied by a high degree of tension. To perform operations for the preparation and distribution of feed on a farm, maintenance of the feed table, as well as for manure harvesting, it is necessary to use a wheeled robotic platform with an automatic positioning system.
 AIMS: Development and testing of the software and hardware system of the Feed Pusher robot for the autonomous execution of operations for the maintenance of the feed table at livestock facilities.
 METHODS: Wheeled robot motion simulation, as well as a mathematical description of the kinematic and dynamic properties of the wheeled robot motion was carried out using the MATLAB software and the Simscape library and the Simulink application. The Figma graphic design software was used to develop layouts of mobile software interfaces for the wheeled robot remote control.
 RESULTS: During the wheeled robot motion simulation, direct and inverse kinematics problems were solved, consisting in finding theω1,ω2, vectors with the input parameters x0,y0,φ0,x,y,φ, as well as the final angle of the path (relative to the horizontal). Layouts of the robot remote control software interfaces have been developed, as well as the frontend and backend development of the program adapted to the use at a smartphone has been carried out. The testing of the wheeled robot was carried out at a livestock facility, during the maintenance of the feed table and the simultaneous execution of operations to push the feed to the fence and dosing of feed additives.
 CONCLUSIONS: The practical value of the research lies in the possibility of using the results of the wheeled robot motion simulation to adjust the operation of the automatic positioning system. At the same time, the farmer using the proposed Feed Pusher robot will ensure an increase in the technological efficiency of cattle keeping, in particular dairy cattle, with an increase in milk yields up to 1 liter per day per head, which was determined during the tests on the farm.

Development of a Computerized Diagnostic System for Brain MRI Tumor Scanning Using a Robust Information Clustering Technique

This paper presents the development of a computerized diagnostic system for brain MRI tumor scanning using a robust information clustering technique. The method used for this study is data collection, data processing, feature extraction, artificial neural network, activation function, training algorithm, and classification. The method was modelled using a structural approach that developed the Artificial Neural Network (ANN) algorithm, using tansig activation function and back-propagation training algorithm. The brain tumor detection algorithm developed was implemented with MATLAB Simulink application, and tested with Mean Square Error (MSE) and Regression (R) analysis. The result showed that the MSE is 0.002488 and the Regression result is 0.9933. The algorithm was also comparatively compared with an existing system and the result showed that the new system achieved better regression performance than the others. Then it was deployed as a clinical decision system for the diagnosis of brain tumors and tested, the result showed that it was able to detect patients with brain MRI data. Keyword : Back-Propagation, Magnetic Resonance Imaging (MRI), Neural Network, Simulink, Tansig.

Mathematical Model of the pH Control System in an In Vitro Model of the Gastrointestinal Tract of Poultry

Introduction. Essential nonlinearity of the chemical reactions of acids and bases determines the control algorithms in the mode of acidification or alkalization, that is, periodic dosing of a minimum volume of acid or alkali. Such regulation may be ineffective, specifically, it allows insufficient or excessive concentration of the controlled substance. The article discusses the problem of precise regulation of the hydrogen index in mini-bioreactors. It is proposed to use a digital model of the acidity control system to select the concentrations of topped-up solutions, determine the regulation methodology, and improve accuracy. The objective of the work is the assurance of required accuracy of pH regulation in an in vitro mini-model of the gastrointestinal tract of a static type.Materials and Methods. The initial block diagram of the model included accumulators and flows. It was the base for the main differential equations characterizing the change in volume and acidity. To correct the acidity readings of the resulting solution by temperature, a static model based on the polynomial approximation of experimental data using the least squares method was created. The structural elements of the mathematical model were investigated in the Matlab Simulink application package. To validate the adequacy of the mathematical model, transient characteristics were determined on a real system of in vitro modeling of the artificial gastrointestinal tract of poultry.Results. Within the framework of this work, the authors created and analyzed a nonlinear mathematical model of pH changes in a bioreactor taking into account external control actions. The flows of hydrochloric acid solution, alkali solution and drain from the reactor were presented as elements of a differential equation describing the accumulation of liquid in the reactor. To improve the accuracy, the solution was modified taking into account the temperature dependence of the hydrogen index. A dosing mathematical model based on a regulator with alkali and acid channels was proposed. The data obtained made it possible to generate a combined model of the pH regulation process in the bioreactor. The adequacy of the solution was confirmed empirically. The models of pH regulator, regulation of the volume of contents in the reactor and chemical reactions were shown in the form of structural diagrams. The transients of a mathematical model and a real control system were compared. It was established that the transient characteristics of the mathematical model and the real system were identical in terms of regulation time. The relative error of regulation of the real system was 0.35 %, and the mathematical model — 0.1 %, which corresponded to the required accuracy of regulation ± 0.1 pH. The influence of the studied flows on the neutralization reaction was shown in the form of graphs.Discussion and Conclusions. The proposed mathematical model will provide selecting optimal methods and algorithms for regulating acidity, which will accelerate the creation of a regulator for the nonlinear process of regulating the hydrogen index. In the future, these developments can be integrated into a comprehensive digital model of the entire artificial gastrointestinal tract of poultry to optimize control algorithms (dosing, mixing, periodicity, etc.), as well as approximation to objects in vivo.

Повышение качества электроэнергии в системах электроснабжения прокатных станов с использованием преобразователей частоты с активными выпрямителями за счет применения специализированных пассивных фильтров

In recent years, the frequency converters (FC) with active rectifiers (AR) have become widespread due to their advantages. The advantages are the possibility of energy recovery in braking modes of electric drive and support of the set value of power factor at the input of AR. At the same time these converters have a significant disadvantage, that is the deterioration of voltage quality in the in-plant 6–35 kV power distribution network due to the imposition of high-frequency harmonics of the input voltage and current of AR on the resonant area of the supply network frequency response. This disadvantage can be eliminated by using special passive filters in the in-plant power networks. They ensure the shift of the main resonance of currents to a zone free from high-frequency harmonics of the FC with AR. It makes possible to reduce the harmonic distortion coefficient in the voltage sections of the main stepdown substation (MSS) of the enterprise. Processing of experimental data is carried out in the Matlab mathematical package with the Simulink application. Using income data of functioning metallurgical complex CherMK of PJSC “Severstal”, the authors carried out the analysis of voltage quality of 10 kV network using specialized passive filters and without them. The article presents the results of the study of the effectiveness of the use of specialized passive filters in the in-plant power supply system of the rolling complex operating at the CherMK of PJSC “Severstal”. The reasons of the deterioration of the voltage quality in the 10 kV distribution network are studied, and as a result, operational breakdown of the modes of sensitive electrical receivers. A complex mathematical model of the 10 kV network has been developed to study the way to improve the harmonic composition of voltage due to installation of specialized passive filters. This filter allows you to adjust the frequency characteristics of the 10 kV network, shift it to an area free of high-frequency harmonics generated by modern frequency converters with active rectifiers. Thus, the resonance of currents and voltages in 10 kV sections is eliminated. As a result, a significant improvement in the shape of the line voltage and a decrease in the harmonic distortion coefficient of voltage THDU = 75,2–91,2 % to values THDU = 0,49–1,4 % is observed. The main result of the research is the recommendation to use a specialized passive filter to eliminate the negative impact of the harmonic component of the current resonance. The research results can be used to design power supply systems of metallurgical enterprises that have powerful electric drives with active rectifiers.

СРАВНИТЕЛЬНЫЙ АНАЛИЗ ЭФФЕКТИВНОСТИ РАЗЛИЧНЫХ МОДЕЛЕЙ ЭЛЕКТРИЧЕСКОГО КОНТУРА ЭЛЕКТРОДУГОВОЙ ПЕЧИ ДЛЯ ИСПОЛЬЗОВАНИЯ В ЦИФРОВОМ ДВОЙНИКЕ

usRelevance Nowadays the metallurgical industry is rapidly developing, which requires a continuous search for innovative solutions aimed at providing consumers with high-quality metal products in the required volumes. To achieve this goal, modern enterprises are faced with a number of scientific and technical tasks, which include increasing the energy efficiency of production. An innovative tool in this case is the development of methods for the digitalization of production, including implementation of digital twins for the control of complicated technological systems. The most energy-intensive equipment at metallurgical enterprises is electric arc furnace (EAF). As operating experience shows, control systems for electrical modes of such units do not always allow EAFs to operate with optimal time, energy and technological parameters, which in turn leads to increased operating costs, such as increased specific energy consumption, consumption of electrodes, etc. As a solution to this problem, a number of scientific studies propose the use of a digital twin for dynamic adaptation of the parameters of the EAF electrical mode control system, capable of calculating the settings of control algorithms during the melting process in such a way as to obtain optimal electrical and technological modes at different stages, as well as optimal dynamic performance quality of impedance regulation on the secondary side of the furnace transformer. One of the important stages in this case is the form of representation of the electrical circuit inside of the digital twin, since the adequacy of the output parameters and the accuracy of the operation of the entire control system will depend on this. Based on the above, an urgent task is to develop an effective method for modeling the electrical circuit of the electric arc furnace for application in a digital twin. Aim of research The paper is devoted to the results of research aimed at the use of various mathematical models of the electrical circuit for application in electric arc furnace’s digital twin. Research methods To process the experimental data, mathematical modeling methods were used in the Matlab environment with the Simulink application. All studies were carried out on the basis of experimental data obtained at operating equipment at domestic and foreign metallurgical plants. Results The significance of the research results lies in increasing the energy efficiency of arc steel-smelting furnaces through the use of a digital twin. This solution will allow to provide the optimal selection of transformer tap reactor tap and operating curve number for each stage of melting, as well as analyze the position of operating points on the electrical characteristics and generate additional control signals for dynamic correction of the lengths of electric arcs. The methods of electric circuit modeling in digital twins presented in the work allow to configure the melting program and optimize the parameters of nonlinear impedance or conductivity controllers of the secondary side of the EAF’s transformer. In addition, it makes possible the analyze and adaptation of the auxiliary blocks in control system — arc ignition, current control and correction of regulator setting signals as a function of the voltage deviation on the primary side of the furnace transformer (relatively to the rated value). Problems associated with calculating matrices of settings for impedances and conductances of the secondary circuit of an EAF for all combinations of transformer taps, reactor taps and all values of operating curves can also be solved. Mathematical models are implemented in the Matlab software environment with the Simulink application.

МЕТОДИКА ВЫБОРА ПАРАМЕТРОВ ПАССИВНОГО ФИЛЬТРА ДЛЯ ПОВЫШЕНИЯ КАЧЕСТВА ЭЛЕКТРОЭНЕРГИИ В ЭЛЕКТРИЧЕСКИХ СЕТЯХ С АКТИВНЫМИ ВЫПРЯМИТЕЛЯМИ

The relevance Due to the wide spread of compact metallurgical plants, which use powerful drives with frequency converters with active rectifiers (FC-AR), an urgent task has become the fight against resonant phenomena in medium voltage electrical networks, since these converters, despite their significant advantages, have a disadvantage — the deterioration of the quality of electricity in the power supply system 6–35 kV. Existing methods of dealing with resonant phenomena in medium voltage electrical networks, in which non-linear elements are present, such as powerful drives of rolling mills with FC-AR used in power supply systems of metallurgical enterprises, do not always allow changing the situation for the better. One way to solve this problem is to use classic traditional filters. Often, the use of traditional filters to eliminate strong voltage distortions in sections of 6–35 kV does not have the desired effect. The installation of traditional filters is accompanied by additional parasitic current resonances, which amplify the intermediate harmonics. These harmonics multiply the oscillations and strongly distort the voltage shape when the frequency response of the distribution network is superimposed with the region of high-frequency harmonics generated by modern FC-AR. Aim of research The article is devoted to the issues of improving the electromagnetic compatibility (EMC) of FC-AR as part of electric drives of rolling mill stands with an internal power supply system for metallurgical plants in the presence of resonant phenomena through the use of specialized passive filters (SPF). Research methods Methods of theoretical and experimental researches are applied in the work. When studying the causes of the occurrence of resonant phenomena, experimental data obtained in the course of research work at the metallurgical plant JSC Metallurgical Plant Balakovo were used. For the processing of experimental data, mathematical modeling methods were used in the Matlab environment with the Simulink application. Results The significance of the results of the work lies in improving the quality of electricity in the distribution electrical networks of mini-plants with FC-AR in the presence of resonant phenomena in the frequency response of the network through the use of SPF. The implementation of the results of the work is an improvement in quality indicators and, as a result, an increase in the reliability of the operation of all power converters in the internal power supply system and a decrease in emergency situations associated with the failure of power elements. The results of the work were implemented at the metallurgical plant of JSC Metallurgical Plant Balakovo. The quantitative indicator of the technical effect of changing the level of the coefficient of the total harmonic components of the voltage in the general sections of the factory GPP КU is: 1) without the use of SPF КU = 10.26 %; 2) when using SPF КU = 1.42 % (relative change δ КU = –72 %). These results can be used at other compact metallurgical enterprises with extended cable lines of medium voltage 6–35 kV and powerful electric drives with FC-AR.

Secures and maintains non-linear control of DFIG-wind turbine by implementing the appropriate protection configuration against overcurrent in the rotor circuit under grid fault

One significant disadvantage of the doubly fed induction generator (DFIG) is its high vulnerability to grid faults, which can be attributed to the direct linkage of its stator windings to the electrical network. The electromagnetic pairing of the stator and rotor in the DFIG implies that a voltage dip causing excessive stator current results in high currents in the sensitive back-to-back inverters and an overcharge in the DC-link capacitor. A comparative study of two protection configurations with a sliding mode non-linear control (SMC) for the rotor transient current for the better operation of the DFIG under network faults is presented in this document. One conventional configuration consists of a crowbar with DC-chopper and another is changed by adding to the crowbar an RL series device known as an appropriate protection configuration (APC). Both are placed within the rotor windings and ride-side converter (RSC) to achieve secures and maintains SMC of DFIG. The comparison of the results reached with the MATLAB/ SIMULINK application is evidenced by the success of these two configuration reduce the high rotor current and DC-link voltage. Additionally, the conventional configuration, in conjunction with the APC, diminishes the current RSC to levels below 0.2kA and exactly 2.25kA, while also being capable of absorbing up to 2.52kA and 1.3kA in the event of a grid fault. So the main difference is that with the APC, the decoupling of the RSC to the rotor in the presence of a fault can be averted, thereby assuring the control of all stator power via the RSC converte.

Simulating linear systems in the MatLab software package using the structural blocks of the Simulink application

The paper considers the peculiarities of linear system simulation in the MatLab software package using the structural blocks of the Simulink application. Typical links of linear systems and their transfer functions are described. The simulation process is exemplified by the system of the object control by its rotation angle. A structural diagram is built for such a system, the mathematical model of which is made in the form of an aperiodic link of the first order. The parameters of the controllers forming the control signal are calculated. A detailed description of the model construction is provided in the Simulink application of the MatLab software package. As a result of simulation, the authors obtained the graphs during the study of the object control system: 1) under external impact without changing controller parameters; 2) under external impact when using a PID controller. The final model was built; it allows comparing the curves of the object rotation control signal in the system with the PD controller and the PID controller as well as displaying the transient curves of the object rotation angle.

INVESTIGATION OF THE STARTING CHARACTERISTICS OF AN ASYNCHRONOUS MOTOR FOR DRIVING A ROTOR-PULSATION APPARATUS USING A FREQUENCY CONVERTER

The method was used to carry out mathematical modeling for the follow-up of transitional processes during the start-up of an asynchronous engine to drive a rotary-pulsation apparatus for the preparation of water-grain feed for the clarity and frequency of the frequency changer. Mathematical modeling of transient processes during the start-up of an asynchronous electric motor for driving a rotary-pulsation apparatus for the preparation of liquid grain feed in the absence and presence of a frequency converter was carried out using the Matlab Simulink application program package. The following start-up parameters of the asynchronous motor were obtained: the current in the stator windings, the speed of rotation of the rotor and the electromagnetic moment on the motor shaft. The dynamic mechanical characteristics of the asynchronous motor during its start-up are obtained. A comparative analysis of simulation results with and without the use of a frequency converter was carried out. It is shown that the use of a frequency converter significantly improves the starting characteristics of an asynchronous motor.

INVESTIGATION OF THE OPERATION MODES OF THE BELT-ROPE CONVEYOR ELECTROMECHANICAL SYSTEM WITH VECTOR-CONTROLLED INDUCTION ELECTRIC MOTORS

Continuous transport systems are the most promising type of movement of loose and artificial materials, have high productivity, technical and economic indicators and are widely used in world practice as main conveyors for the coal and mining industry. A special place in continuous transport is occupied by belt-rope conveyors, which are capable of transporting cargo over a distance of more than 30 km in one stop. As a rule, these main conveyors do not provide for the adjustment of movement parameters, the start is carried out using soft start systems. At the same time, such systems have high requirements for the parameters of dynamic modes of operation, the accuracy of working out the given movement program and the level of energy efficiency. The paper proposes a modern electric drive system using vector-controlled induction electric motors. The structure of the electromechanical system is given. A mathematical model of the electromechanical system was built using known methods. As part of the “MATLAB” Simulink application program package, a model for the investigation of dynamic modes of conveyor operation was obtained. On a specific example, a research of dynamic and static modes of conveyor operation with static load and the speed of movement variations of the traction element was carried out. Studies of the accuracy of working out the given law of motion showed that the maximum dynamic error in terms of speed and current is worked out in a time of up to 0.06 s. The maximum level of its amplitude does not exceed 0.33% of the constant speed of movement, which does not cause oscillatory processes in the conveyor and ensures stable operation of the electromechanical system. Investigation of the electromechanical system energy characteristics was conducted. Losses of active power do not exceed 12.5% of the consumed in the entire range of variation of the static load and speed of the traction element. Recommendations for the use of electromechanical systems with vector-controlled induction electric motors in belt-rope conveyors have been formulated.

Simulation of an automatic piloting system based on the MATLAB Simulink program for complex production automation

The main conclusions of the convergence methods are given. The method of proportional approximation is described in detail. Structural schemes are presented: the block of formation of the control action, the block of the kinematic model of the three-contour control system of the object and the blocks of movement of the object "target" and the control object. The work was carried out in a package of application programs for solving MATLAB technical computing problems. The simulation process was performed in the MATLAB Simulink extension. The practical significance of the work is the study of the basic principles of modeling automatic control systems using various methods of convergence; the study of the method of proportional convergence, the creation of models of the movement of objects in the MATLAB Simulink application software package. This work can be used not only for teaching students in the field of development of electronic automatic control devices and for laboratory work, but also in the creation and design of real receiving radio navigation devices both in production and within higher education institutions. Familiarization and studies of the above software are conducted at the Department of Radioelectronic Systems and Complexes of one of the leading engineering universities of the Russian Federation – Bauman Moscow State Technical University.

РОЗВ'ЯЗАННЯ ЗАДАЧІ АНАЛІЗУ ДИНАМІЧНИХ ПРОЦЕСІВ У ВЕНТИЛЬНІЙ ЕЛЕКТРИЧНІЙ МАШИНІ

The work solves an actual problem related to the development of a mathematical description and creation of models of valve machines, which are of important scientific and practical importance for the study of operating characteristics and the design of new control algorithms. We proposed a solution to the problem of analysis of dynamic processes in a valve electric machine using the Simulink application of the MATLAB environment. We proposed a solution to the problem of analysis of dynamic processes in a valve electric machine using the Simulink application of the MATLAB environment. The created models make it possible to obtain the main characteristics by which the working properties of engines are evaluated: electromechanical, mechanical. The results show that the operation of the valve machine is practically similar to the direct current machine. When building a model of a valve electric machine, control with current feedback and maintaining id = 0 should be carried out. This reduces the deterioration of mechanical, control and energy characteristics in a stable mode of operation. In general, if we compare a valve machine with a direct current machine, then its features are mainly manifested in the stable mode in the form of deterioration of mechanical, control and energy characteristics. As for the dynamics, the simulation results show that the valve machine is practically analogous to the DC machine. Analyzing the model as a whole and using the measuring tools provided by Simulink, it is possible to determine the losses in the motor, calculate the equivalent currents, torques and powers and check the correctness of the motor selection. The results obtained from such a generalized analysis can be extended to different engine operating modes. The proposed model for solving the problem of analysis of dynamic processes in a valve electric machine using the Simulink application of the MATLAB environment is characterized by functionality and the possibility of using the obtained results and the model itself in the design of modern electrical equipment.

Modelling and Control of SEPIC and BIDC Converter Based off-Board EV Battery Charger using PV Array

Recent years have seen a dramatic increase in the usage of renewable energy sources in a variety of industries, including the automotive sector where it plays a role in charging the batteries of electric vehicles (EVs). Here, we present a method for lightweight EVs that uses a solar energy power conversion with SEPIC and bidirectional interleaved DC-DC converter (BIDC) to charge their batteries from the grid instead of on-board. The suggested technology can recharge the electric vehicle's battery throughout daylight and nighttime hours. The EV battery and the backup battery both get charged during peak sunlight hours, and the backup battery helps charge the EV battery when the sun isn't out. In order to test the effectiveness of the proposed charging method, a simulation was run in the MATLAB software using the Simulink application.

СОВМЕСТНОЕ МОДЕЛИРОВАНИЕ ДВИЖЕНИЯ ПАРАЛЛЕЛЬНОГО МАНИПУЛЯТОРА C ИСПОЛЬЗОВАНИЕМ ADAMS-MATLAB

The article presents the methods and results of the analysis of the movement of a modeling manipulator such as the Hugh-Stewart platform using Adams-Matlab in order to check and develop a possible trajectory of the working body. Application of Matlab Simulink for solving kinematics problems: determining the extension length of rods along a given trajectory of the movement of the working body. A feature of the Simulink application scheme is the export of physical and mechanical parameters of a solid model from Adams. Mutual integration of Matlab Simulink and Adams View evaluate the implementation of the possibility of implementing a kinematic, comprehensive and force analysis of the mechanism, taking into account its design features due to the use of an apparent prototype. The proposed method of joint modeling is presented in the form of a detailed description of the content of Simulink circuit blocks, their interaction in modeling, the exact mathematical apparatus and the conditions for implementing mutual thoroughness of the Matlab and Adams software packages. The technique was tested on the ascent from constructive platforms while moving along a sexual character such as a given trajectory. The results of a computational experiment are proposed and an analysis is made of the coordinate correspondence of the actual trajectory obtained as a result of modeling in joint simulation with the initial given trajectory for various types of motion.

DYNAMIC CHARACTERISTICS INVESTIGATION OF THE SYSTEM "SOFTSTARTER - INDUCTION MOTOR" IN THE MODE OF OPERATION WITH REDUSED SPEED

In the article operation of the system "softstarter - induction motor" with reduced speed is carried out. The relative cheapness of thyristor starting devices for induction motors in comparison with frequency inverters leads to their increasing of industry installation. However, the implementation of some modes of operation, such as rotation at a reduced test speed, may not always be possible for particular processes. This is especially true of increasing the amplitude of speed fluctuations with increasing motor torque. The paper presents the settings of the serial starter SSW900 from WEG, which affect the operation of the induction motor at low speed. To study the impact in the work, a model was compiled in the MATLAB software environment using the Simulink application. The correspondence of the parameters of the functional models to the settings of the existing soft-start device is determined. The reduction of the motor speed is provided by reducing the frequency and, accordingly, the amplitude of the voltage applied to the motor windings. To reduce the carrier frequency relative to the supply frequency, the mode of passing certain voltage half-waves is used. In MATLAB, this is achieved through the use of Pulse_generator blocks, which pass control pulses only at permitted intervals. By changing the opening angle of the thyristors, graphs of transients in velocity were obtained and the amplitudes of oscillations at the fan nature of the load were determined. In addition, the results of the study of the system on a physical model were obtained and a comparative analysis of the results was performed. Thus, the formation of reduced frequency, proposed in the development of a mathematical model in MATLAB provides a reduction in engine speed to 1/7 of the nominal. The amplitude of speed fluctuations when setting the maximum torque reaches values ​​that significantly limit the possibility of using this mode for long-term operation of the equipment, which is also confirmed by experimental studies.

PENINGKATAN MOTIVASI BELAJAR PESERTA DIDIK DENGAN APLIKASI MATLAB SIMULINK DI SMKN 2 SIGLI

The problem that occurs at SMKN 2 Sigli is the learning process that has not used learning media in the form of application software, one of which is Matlab Simulink which can later simplify and increase the motivation of students in the classroom. This study aims to determine whether the introduction of the Matlab Simulink application can increase the learning motivation of students in class XI at SMKN 2 Sigli and to determine the response of students after the introduction of the Matlab Simulink application in class XI at SMK 2 Sigli. This type of research uses an experimental model with a quantitative approach. The population in this study were all students at SMK N 2 Sigli as many as 751 people. The sample in this study is class XI students, totaling 17 people, sampling using purposive sampling method. This research instrument includes observation and questionnaires. The results of observing the activeness of students using the Matlab Simulink application increased according to the criteria for the percentage of 92.85% (highly motivated). The results of the motivation of students as many as 52.54% who chose very well were included in the moderately motivated category and gave a positive response to the use of the Matlab Simulink application for class XI SMK Negeri 2 Sigli.