Pub Date : 2021-12-03DOI: 10.20998/2074-272x.2021.6.02
S. Goolak, I. Riabov, V. Tkachenko, S. Sapronova, I. Rubanik
The aim of the work is to develop a mathematical model of the traction motor of the pulsating current of an electric locomotive taking into account the magnetic losses in the motor steel to determine the starting parameters depending on the voltage of the armature winding. Methodology. Mathematical modeling of electromagnetic processes in a traction motor of pulsating current is applied taking into account the nonlinear nature of the armature inductance, the inductance of the excitation winding and the nonlinear nature of the universal magnetic characteristic. The magnetic losses in the steel of the traction motor were taken into account by establishing the dependence of these losses on the frequency of reversal, the magnetic flux in the magnetic circuit of the motor and the geometric dimensions of the motor. Results. The mathematical model of calculation of starting parameters of the traction engine of the pulsating current of the traction drive of the electric locomotive of alternating current taking into account the equation of instantaneous value of losses in engine steel is developed. The dynamic characteristics of the traction motor with pulsating current are obtained. It allows to investigate starting parameters of the traction engine on the basis of the received mathematical model and to design elements of the traction drive of the electric locomotive according to the specification, to choose optimum design parameters. Originality. For the first time a comprehensive study of the pulsating current traction motor was carried out taking into account the nonlinear nature of the armature inductance, excitation winding inductance and nonlinear nature of the universal magnetic characteristic and taking into account the magnetic losses in the motor steel. Practical significance. The model of the traction motor of pulsating current taking into account losses in steel of the engine on the basis of the carried-out calculation is developed. Experimental studies have confirmed the adequacy of the model, which allows to apply the obtained model to develop a mathematical model of an AC electric locomotive to study the electrodynamic processes in it at different modes of operation of the electric locomotive.
{"title":"Model of pulsating current traction motor taking into consideration magnetic losses in steel","authors":"S. Goolak, I. Riabov, V. Tkachenko, S. Sapronova, I. Rubanik","doi":"10.20998/2074-272x.2021.6.02","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.6.02","url":null,"abstract":"The aim of the work is to develop a mathematical model of the traction motor of the pulsating current of an electric locomotive taking into account the magnetic losses in the motor steel to determine the starting parameters depending on the voltage of the armature winding. Methodology. Mathematical modeling of electromagnetic processes in a traction motor of pulsating current is applied taking into account the nonlinear nature of the armature inductance, the inductance of the excitation winding and the nonlinear nature of the universal magnetic characteristic. The magnetic losses in the steel of the traction motor were taken into account by establishing the dependence of these losses on the frequency of reversal, the magnetic flux in the magnetic circuit of the motor and the geometric dimensions of the motor. Results. The mathematical model of calculation of starting parameters of the traction engine of the pulsating current of the traction drive of the electric locomotive of alternating current taking into account the equation of instantaneous value of losses in engine steel is developed. The dynamic characteristics of the traction motor with pulsating current are obtained. It allows to investigate starting parameters of the traction engine on the basis of the received mathematical model and to design elements of the traction drive of the electric locomotive according to the specification, to choose optimum design parameters. Originality. For the first time a comprehensive study of the pulsating current traction motor was carried out taking into account the nonlinear nature of the armature inductance, excitation winding inductance and nonlinear nature of the universal magnetic characteristic and taking into account the magnetic losses in the motor steel. Practical significance. The model of the traction motor of pulsating current taking into account losses in steel of the engine on the basis of the carried-out calculation is developed. Experimental studies have confirmed the adequacy of the model, which allows to apply the obtained model to develop a mathematical model of an AC electric locomotive to study the electrodynamic processes in it at different modes of operation of the electric locomotive.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68225584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-03DOI: 10.20998/2074-272x.2021.6.09
Zakaria Laggoun, H. Benalla, K. Nebti
Introduction. The quality of electrical energy is essential during disturbances, at the level of power electronic devices will suffer serious operating problems causing dangerous damage. Aim. A new approach to direct power control without grid voltage sensor improves the quality and control of instantaneous active and reactive power converters. Methodology. First, the technique without network voltage sensor with a direct power control based on a switching table, which is a classic approach, is discussed and its performance is analyzed under increasing and decreasing load. In addition, the performance of the proposed technique is also analyzed under the same circumstances and their performance is compared. Originality. The new method consists of a nonlinear grid voltage modulated controller and a conventional controller which guarantees very good results in a polluted network. The proposed method is verified using MATLAB/Simulink. Results. The simulation results under different input voltage conditions show that the proposed method not only has good tracking performance in active and reactive power, but also reduces the current total harmonic distortion to 1.9 %, which is good lower than the requirement for network operation.
{"title":"A power quality enhanced for the wind turbine with sensorless direct power control under different input voltage conditions","authors":"Zakaria Laggoun, H. Benalla, K. Nebti","doi":"10.20998/2074-272x.2021.6.09","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.6.09","url":null,"abstract":"Introduction. The quality of electrical energy is essential during disturbances, at the level of power electronic devices will suffer serious operating problems causing dangerous damage. Aim. A new approach to direct power control without grid voltage sensor improves the quality and control of instantaneous active and reactive power converters. Methodology. First, the technique without network voltage sensor with a direct power control based on a switching table, which is a classic approach, is discussed and its performance is analyzed under increasing and decreasing load. In addition, the performance of the proposed technique is also analyzed under the same circumstances and their performance is compared. Originality. The new method consists of a nonlinear grid voltage modulated controller and a conventional controller which guarantees very good results in a polluted network. The proposed method is verified using MATLAB/Simulink. Results. The simulation results under different input voltage conditions show that the proposed method not only has good tracking performance in active and reactive power, but also reduces the current total harmonic distortion to 1.9 %, which is good lower than the requirement for network operation.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42072520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-03DOI: 10.20998/2074-272x.2021.6.08
S. A. Khan, T. Mahmood, K.S. Awan
Introduction. The huge demand of green energy over past few decades have drawn the interest of scientists and researchers. Solar energy is the most abundant and easily available source but there have been so many problems with its optimum extraction of output. The factors affecting the maximum power point tracking of PV systems are input irradiance, temperature, load etc. The variations in irradiance level lead to partial shading that causes reduction in performance by not letting system to operate at maximum power point. Many methods have been proposed in literature to optimize the performance of PV systems but each method has shortcomings that have failed all of them. The actual problem occurs when partial shading is very strong; this is where most of the methods totally fail. So proposed work addresses this issue and solves it to the fullest. The novelty in the proposed work is that it introduces a new nature-based algorithm that works on the principle of plant propagation. It is a natural optimization technique that plants follow to survive and propagate in different environmental conditions. The proposed method efficiently tracks the global peak under all shading conditions and is simple to implement with high accuracy and tracking speed. Purpose. Building an algorithm that can track global peak of photovoltaic systems under all shading conditions and extracts the maximum possible power from the system, and is simple and easy to implement. Methods. The method is implemented in MATLAB / Simulink on an electrical model that uses a PV array model. Different shadings are applied to check for the results. Results. The results have shown that for different photovoltaic configurations the algorithm performs very good under uniform and partial shadings conditions. Its accuracy, tracking efficiency and tracking time has increased reasonably. Practical value. The project can be very beneficial to people as it enhances the performances of PV systems that can make them self-sufficient in electrical energy, focuses on sustainable development and reduces pollution. This way it can have huge impact on human life.
{"title":"A nature based novel maximum power point tracking algorithm for partial shading conditions","authors":"S. A. Khan, T. Mahmood, K.S. Awan","doi":"10.20998/2074-272x.2021.6.08","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.6.08","url":null,"abstract":"Introduction. The huge demand of green energy over past few decades have drawn the interest of scientists and researchers. Solar energy is the most abundant and easily available source but there have been so many problems with its optimum extraction of output. The factors affecting the maximum power point tracking of PV systems are input irradiance, temperature, load etc. The variations in irradiance level lead to partial shading that causes reduction in performance by not letting system to operate at maximum power point. Many methods have been proposed in literature to optimize the performance of PV systems but each method has shortcomings that have failed all of them. The actual problem occurs when partial shading is very strong; this is where most of the methods totally fail. So proposed work addresses this issue and solves it to the fullest. The novelty in the proposed work is that it introduces a new nature-based algorithm that works on the principle of plant propagation. It is a natural optimization technique that plants follow to survive and propagate in different environmental conditions. The proposed method efficiently tracks the global peak under all shading conditions and is simple to implement with high accuracy and tracking speed. Purpose. Building an algorithm that can track global peak of photovoltaic systems under all shading conditions and extracts the maximum possible power from the system, and is simple and easy to implement. Methods. The method is implemented in MATLAB / Simulink on an electrical model that uses a PV array model. Different shadings are applied to check for the results. Results. The results have shown that for different photovoltaic configurations the algorithm performs very good under uniform and partial shadings conditions. Its accuracy, tracking efficiency and tracking time has increased reasonably. Practical value. The project can be very beneficial to people as it enhances the performances of PV systems that can make them self-sufficient in electrical energy, focuses on sustainable development and reduces pollution. This way it can have huge impact on human life.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49636986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-03DOI: 10.20998/2074-272x.2021.6.03
K. Akkouchi, L. Rahmani, R. Lebied
Purpose. This article proposes a new strategy for Direct Power Control (DPC) based on the use of Artificial Neural Networks (ANN-DPC). The proposed ANN-DPC scheme is based on the replacement of PI and hysteresis regulators by neural regulators. Simulation results for a 1 kW system are provided to demonstrate the efficiency and robustness of the proposed control strategy during variations in active and reactive power and in DC bus voltage. Methodology. Our strategy is based on direct control of instant active and reactive powers. The voltage regulator and hysteresis are replaced by more efficient and robust artificial neuron networks. The proposed control technique strategy is validated using MATLAB / Simulink software to analysis the working performances. Results. The results obtained clearly show that neuronal regulators have good dynamic performances compared to conventional regulators (minimum response time, without overshoots). Originality. Regulation of continuous bus voltage and sinusoidal currents on the network side by using artificial neuron networks. Practical value. The work concerns the comparative study and the application of DPC based on ANN techniques to achieve a good performance control system of the permanent magnet synchronous generator. This article presents a comparative study between the conventional DPC control and the ANN-DPC control. The first strategy based on the use of a PI controller for the control of the continuous bus voltage and hysteresis regulators for the instantaneous powers control. In the second technique, the PI and hysteresis regulators are replaced by more efficient neuronal controllers more robust for the system parameters variation. The study is validated by the simulation results based on MATLAB / Simulink software.
{"title":"New application of artificial neural network-based direct power control for permanent magnet synchronous generator","authors":"K. Akkouchi, L. Rahmani, R. Lebied","doi":"10.20998/2074-272x.2021.6.03","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.6.03","url":null,"abstract":"Purpose. This article proposes a new strategy for Direct Power Control (DPC) based on the use of Artificial Neural Networks (ANN-DPC). The proposed ANN-DPC scheme is based on the replacement of PI and hysteresis regulators by neural regulators. Simulation results for a 1 kW system are provided to demonstrate the efficiency and robustness of the proposed control strategy during variations in active and reactive power and in DC bus voltage. Methodology. Our strategy is based on direct control of instant active and reactive powers. The voltage regulator and hysteresis are replaced by more efficient and robust artificial neuron networks. The proposed control technique strategy is validated using MATLAB / Simulink software to analysis the working performances. Results. The results obtained clearly show that neuronal regulators have good dynamic performances compared to conventional regulators (minimum response time, without overshoots). Originality. Regulation of continuous bus voltage and sinusoidal currents on the network side by using artificial neuron networks. Practical value. The work concerns the comparative study and the application of DPC based on ANN techniques to achieve a good performance control system of the permanent magnet synchronous generator. This article presents a comparative study between the conventional DPC control and the ANN-DPC control. The first strategy based on the use of a PI controller for the control of the continuous bus voltage and hysteresis regulators for the instantaneous powers control. In the second technique, the PI and hysteresis regulators are replaced by more efficient neuronal controllers more robust for the system parameters variation. The study is validated by the simulation results based on MATLAB / Simulink software.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41925486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.01
V. Bolyukh, I. S. Schukin, J. Lasocki
Purpose. The purpose of the article is to determine the influence of the initial displacement of the windings on the indicators of an electromechanical induction accelerator of a cylindrical configuration with pulsed excitation from a capacitive energy storage and with short-term excitation from an alternating voltage source. Methodology. To take into account the interrelated electrical, magnetic, mechanical and thermal processes, as well as a number of nonlinear dependencies, we use the lumped parameters of the windings, and the solutions of the equations describing these processes are presented in a recurrent form. The mathematical model of the accelerator takes into account the variable magnetic coupling between the windings during the excitation of the inductor winding. When calculating the parameters and characteristics of the accelerator, a cyclic algorithm is used. Results. At a frequency of an alternating voltage source of 50 Hz, the current amplitude in the armature winding is less than in the inductor winding. With an increase in the source frequency to 250 Hz, the phase shift between the winding currents decreases. The current in the inductor winding decreases, and in the armature winding it increases. The accelerating components of the force increase, and the braking ones decrease. With an increase in the source frequency to 500 Hz, the current density in the armature winding exceeds that in the inductor winding. In this case, the phase shift between the windings is further reduced. Originality. When a cylindrical accelerator is excited, the largest amplitude of the current density in the inductor winding occurs at the maximum initial displacement of the windings, but the amplitude of the current density in the armature winding is the smallest. The largest value of the current density in the armature winding occurs in the absence of an initial displacement. When excited from a capacitive energy storage, the electrodynamic force between the windings has an initial accelerating and subsequent braking components. As a result, the speed of the armature initially increases to a maximum value, but decreases towards the end of the electromagnetic process. When a cylindrical accelerator is excited from an alternating voltage source, a phase shift occurs between the currents in the windings, which leads to the appearance of alternating accelerating and decelerating components of electrodynamic forces. The accelerating components of the force prevail over the braking components, which ensures the movement of the armature. Practical value. At a frequency of an alternating voltage source of 50 Hz, the highest speed at the output of the accelerator vzf=0.5 m/s is realized at an initial displacement of the windings z0=6.2 mm, at a frequency of 250 Hz, the highest speed vzf=2.4 m/s is realized at z0=3.1 mm, and at a frequency of 500 Hz the highest speed vzf=2.29 m/s is realized at z0=2.3 mm.
{"title":"Influence of the initial winding displacement on the indicators of the electromechanical induction accelerator of cylindrical configuration","authors":"V. Bolyukh, I. S. Schukin, J. Lasocki","doi":"10.20998/2074-272x.2021.5.01","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.01","url":null,"abstract":"Purpose. The purpose of the article is to determine the influence of the initial displacement of the windings on the indicators of an electromechanical induction accelerator of a cylindrical configuration with pulsed excitation from a capacitive energy storage and with short-term excitation from an alternating voltage source. Methodology. To take into account the interrelated electrical, magnetic, mechanical and thermal processes, as well as a number of nonlinear dependencies, we use the lumped parameters of the windings, and the solutions of the equations describing these processes are presented in a recurrent form. The mathematical model of the accelerator takes into account the variable magnetic coupling between the windings during the excitation of the inductor winding. When calculating the parameters and characteristics of the accelerator, a cyclic algorithm is used. Results. At a frequency of an alternating voltage source of 50 Hz, the current amplitude in the armature winding is less than in the inductor winding. With an increase in the source frequency to 250 Hz, the phase shift between the winding currents decreases. The current in the inductor winding decreases, and in the armature winding it increases. The accelerating components of the force increase, and the braking ones decrease. With an increase in the source frequency to 500 Hz, the current density in the armature winding exceeds that in the inductor winding. In this case, the phase shift between the windings is further reduced. Originality. When a cylindrical accelerator is excited, the largest amplitude of the current density in the inductor winding occurs at the maximum initial displacement of the windings, but the amplitude of the current density in the armature winding is the smallest. The largest value of the current density in the armature winding occurs in the absence of an initial displacement. When excited from a capacitive energy storage, the electrodynamic force between the windings has an initial accelerating and subsequent braking components. As a result, the speed of the armature initially increases to a maximum value, but decreases towards the end of the electromagnetic process. When a cylindrical accelerator is excited from an alternating voltage source, a phase shift occurs between the currents in the windings, which leads to the appearance of alternating accelerating and decelerating components of electrodynamic forces. The accelerating components of the force prevail over the braking components, which ensures the movement of the armature. Practical value. At a frequency of an alternating voltage source of 50 Hz, the highest speed at the output of the accelerator vzf=0.5 m/s is realized at an initial displacement of the windings z0=6.2 mm, at a frequency of 250 Hz, the highest speed vzf=2.4 m/s is realized at z0=3.1 mm, and at a frequency of 500 Hz the highest speed vzf=2.29 m/s is realized at z0=2.3 mm.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49141690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.03
Z. A. Gulshan, M. Ali, M. S. Shah, D. Nouman, M. Anwar, M. F. Ullah
Introduction. Unmanned aerial vehicles as quadcopters, twin rotors, fixed-wing crafts, and helicopters are being used in many applications these days. Control approaches applied on the quadrotor after decoupling the model or separate altitude control and trajectory tracking have been reported in the literature. A robust linear H∞ controller has been designed for both altitude control and circular trajectory tracking at the desired altitude. Problem. The ability of the quadrotor system to hover at a certain height and track any desired trajectory makes their use in many industrial applications in both military and civil applications. Once a controller has been designed, it may not be able to maintain the desired performance in practical scenarios, i.e. in presence of wind gusts. Originality. This work presents the control strategy to ensure both altitude control and trajectory tracking using a single controller. Purpose. However, there is a need for a single controller that ensures both altitude control and trajectory tracking. Novelty. This paper presents a robust H∞ control for altitude control and trajectory tracking for a six degree of freedom of unmanned aerial vehicles quadrotor. Methodology. Multi input multi output robust H∞ controller has been proposed for the quadrotor for altitude control and tracking the desired reference. For the controller validation, a simulation environment is developed in which a 3D trajectory is tracked by the proposed control methodology. Results. Simulation results depict that the controller is efficient enough to achieve the desired objective at minimal control efforts. Practical value. To verify that the proposed approach is able to ensure stability, altitude control, and trajectory tracking under practical situations, the performance of the proposed control is tested in presence of wind gusts. The ability of the controller to cater to the disturbances within fractions of seconds and maintaining both transient and steady-state performance proves the effectiveness of the controller.
{"title":"A robust control design approach for altitude control and trajectory tracking of a quadrotor","authors":"Z. A. Gulshan, M. Ali, M. S. Shah, D. Nouman, M. Anwar, M. F. Ullah","doi":"10.20998/2074-272x.2021.5.03","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.03","url":null,"abstract":"Introduction. Unmanned aerial vehicles as quadcopters, twin rotors, fixed-wing crafts, and helicopters are being used in many applications these days. Control approaches applied on the quadrotor after decoupling the model or separate altitude control and trajectory tracking have been reported in the literature. A robust linear H∞ controller has been designed for both altitude control and circular trajectory tracking at the desired altitude. Problem. The ability of the quadrotor system to hover at a certain height and track any desired trajectory makes their use in many industrial applications in both military and civil applications. Once a controller has been designed, it may not be able to maintain the desired performance in practical scenarios, i.e. in presence of wind gusts. Originality. This work presents the control strategy to ensure both altitude control and trajectory tracking using a single controller. Purpose. However, there is a need for a single controller that ensures both altitude control and trajectory tracking. Novelty. This paper presents a robust H∞ control for altitude control and trajectory tracking for a six degree of freedom of unmanned aerial vehicles quadrotor. Methodology. Multi input multi output robust H∞ controller has been proposed for the quadrotor for altitude control and tracking the desired reference. For the controller validation, a simulation environment is developed in which a 3D trajectory is tracked by the proposed control methodology. Results. Simulation results depict that the controller is efficient enough to achieve the desired objective at minimal control efforts. Practical value. To verify that the proposed approach is able to ensure stability, altitude control, and trajectory tracking under practical situations, the performance of the proposed control is tested in presence of wind gusts. The ability of the controller to cater to the disturbances within fractions of seconds and maintaining both transient and steady-state performance proves the effectiveness of the controller.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43359567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.09
D. Koliushko, S. Rudenko, A. N. Saliba
The paper is devoted to the problem of determining the geoelectric structure of the soil within the procedure of testing the grounding arrangements of existing power plants and substations to the required depth in conditions of dense development. To solve the problem, it was proposed to use the Schlumbergers method , which has a greater sounding depth compared to the Wenner electrode array. The purpose of the work is to develop a mathematical model for interpreting the results of soil sounding by the Schlumberger method in the form of a four-layer geoelectric structure. Methodology. To construct a mathematical model, it is proposed to use the solution of a particular problem about the field of a point current source, which, like the observation point, is located in the first layer of a four-layer soil. Based on this expressions, a system of linear algebraic equations of the 7-th order with respect to the unknown coefficients ai and bi was compiled. On the basis of its analytical solution, an expression for the potential of the electric field was obtained for conducting VES (the point current source and the observation point are located only on the soil surface). Results. Comparison of the results of soil sounding by the Schlumberger installation and the interpretation of its results for the same points shows a sufficient degree of approximation: the maximum relative error does not exceed 9.7 % (for the second point), and the average relative error is 3.6 %. Originality. Based on the obtained expression, a test version of the program was implemented in Visual Basic for Applications to interpret the results of VES by the Schlumberger method. To check the obtained expressions, the interpretation of the VES results was carried out on the territory of a 150 kV substation of one of the mining and processing plants in the city of Kriviy Rih. Practical significance. The developed mathematical model will make it possible to increase the sounding depth, and, consequently, the accuracy of determining the standardized parameters of the grounding arrangements of power stations and substations.
本文致力于在密集开发条件下,在将现有发电厂和变电站的接地布置测试到所需深度的过程中,确定土壤的地电结构的问题。为了解决这个问题,建议使用斯伦贝谢方法,该方法与温纳电极阵列相比具有更大的探测深度。这项工作的目的是开发一个数学模型,以四层地电结构的形式解释斯伦贝谢方法的土壤测深结果。方法论为了构建数学模型,建议使用关于点电流源场的特定问题的解,该点电流源与观测点一样,位于四层土壤的第一层。基于这些表达式,编制了一个关于未知系数ai和bi的7阶线性代数方程组。在解析解的基础上,得到了传导VES(点电流源和观测点仅位于土壤表面)时电场电势的表达式。后果斯伦贝谢装置土壤测深结果的比较及其对相同点的结果的解释显示了足够的近似度:最大相对误差不超过9.7%(第二点),平均相对误差为3.6%。独创性基于获得的表达式,在Visual Basic for Applications中实现了该程序的测试版本,以通过斯伦贝谢方法解释VES的结果。为了检查所获得的表达式,对VES结果的解释是在Kriviy Rih市一家采矿和加工厂的150 kV变电站的范围内进行的。实际意义。所开发的数学模型将有可能增加探测深度,从而提高确定发电站和变电站接地布置标准化参数的准确性。
{"title":"Method of integro-differential equations for interpreting the results of vertical electrical sounding of the soil","authors":"D. Koliushko, S. Rudenko, A. N. Saliba","doi":"10.20998/2074-272x.2021.5.09","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.09","url":null,"abstract":"The paper is devoted to the problem of determining the geoelectric structure of the soil within the procedure of testing the grounding arrangements of existing power plants and substations to the required depth in conditions of dense development. To solve the problem, it was proposed to use the Schlumbergers method , which has a greater sounding depth compared to the Wenner electrode array. The purpose of the work is to develop a mathematical model for interpreting the results of soil sounding by the Schlumberger method in the form of a four-layer geoelectric structure. Methodology. To construct a mathematical model, it is proposed to use the solution of a particular problem about the field of a point current source, which, like the observation point, is located in the first layer of a four-layer soil. Based on this expressions, a system of linear algebraic equations of the 7-th order with respect to the unknown coefficients ai and bi was compiled. On the basis of its analytical solution, an expression for the potential of the electric field was obtained for conducting VES (the point current source and the observation point are located only on the soil surface). Results. Comparison of the results of soil sounding by the Schlumberger installation and the interpretation of its results for the same points shows a sufficient degree of approximation: the maximum relative error does not exceed 9.7 % (for the second point), and the average relative error is 3.6 %. Originality. Based on the obtained expression, a test version of the program was implemented in Visual Basic for Applications to interpret the results of VES by the Schlumberger method. To check the obtained expressions, the interpretation of the VES results was carried out on the territory of a 150 kV substation of one of the mining and processing plants in the city of Kriviy Rih. Practical significance. The developed mathematical model will make it possible to increase the sounding depth, and, consequently, the accuracy of determining the standardized parameters of the grounding arrangements of power stations and substations.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41796325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.02
P. Andrienko, O. Nemykina, A. Andrienko, R. Mokhnach
Purpose. Investigation of the influence of higher harmonics of current on current distribution, voltage and power losses in the supply systems of crane trolleys and development of a calculation method for practical use. Methodology. The analytical method and the results of the modeling method were used for research. Results. Analytical relationships have been obtained that make it possible to determine the current distribution, voltage and power losses in the systems of induction feeding of crane trolleys, taking into account the composition and amplitude of the higher harmonics of the current. Originality. For the first time, analytical dependences are obtained that take into account the effect of changing the trolley parameters on the frequency in the feed systems. Numerical values have been determined for the most commonly used induction feed systems for cranes. It is shown that with an increase in the cross-section of the feed bar there is a decrease in the main, and especially additional, losses. Practical value. Theoretical relationships have been obtained that can be used to calculate the optimization of induction feed systems in the presence of higher harmonic currents arising in power systems during operation of crane semiconductor controlled electric drives.
{"title":"Research of operating modes of conductors in power supply systems of cranes with induction feed, taking into account the influence of higher harmonics of the current","authors":"P. Andrienko, O. Nemykina, A. Andrienko, R. Mokhnach","doi":"10.20998/2074-272x.2021.5.02","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.02","url":null,"abstract":"Purpose. Investigation of the influence of higher harmonics of current on current distribution, voltage and power losses in the supply systems of crane trolleys and development of a calculation method for practical use. Methodology. The analytical method and the results of the modeling method were used for research. Results. Analytical relationships have been obtained that make it possible to determine the current distribution, voltage and power losses in the systems of induction feeding of crane trolleys, taking into account the composition and amplitude of the higher harmonics of the current. Originality. For the first time, analytical dependences are obtained that take into account the effect of changing the trolley parameters on the frequency in the feed systems. Numerical values have been determined for the most commonly used induction feed systems for cranes. It is shown that with an increase in the cross-section of the feed bar there is a decrease in the main, and especially additional, losses. Practical value. Theoretical relationships have been obtained that can be used to calculate the optimization of induction feed systems in the presence of higher harmonic currents arising in power systems during operation of crane semiconductor controlled electric drives.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47261036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.07
O. Shutenko, S. Ponomarenko
Introduction. Ensuring the operational reliability of power transformers is an urgent task for the power industry in Ukraine and for most foreign countries. One of the ways to solve this problem is the correction of maximum permissible values of insulation parameters. However, such a correction is fundamentally impossible without an analysis of the laws of distribution of diagnostic indicators in the equipment with different states. The purpose of the research is to analyse the laws of distribution of the quality indicators of transformer oil with different states in 110 and 330 kV transformers. Novelty. It was found that both 330 kV autotransformers and 110 kV transformers have the displacements between the mathematical expectations of the distribution density of usable oil indicators. It caused by different service life of the analysed transformers and different values of load factors. This indicates the need to consider the influence of these factors when correcting the maximum permissible values of oil indicators. Also, the presence of displacement between the distribution densities of some indicators of usable oil in 110 kV transformers and 330 kV autotransformers has been revealed. It indicates a different intensity of oxidation reactions in transformers with different voltage class. In order to reduce the heterogeneity of initial data the procedure of statistical processing of in-service test results has been proposed as a method. This procedure combines the use of a priori information about the service life of equipment and values of load factors with the elements of statistical hypothesis testing. The results of the analysis of the distribution laws of transformer oil indicators with different states have shown that for both usable and unusable oil the values of oil indicators obey the Weibull distribution. Values of the shape and scale parameters for each of the obtained indices arrays have been obtained, as well as calculated and critical values of the goodness-of-fit criteria. Practical value. Obtained values of the distribution law parameters of the transformer oil indicators with different states, considering the service life and operating conditions allow to perform the correction of the maximum permissible values of the indicators using the statistical decision-making methods.
{"title":"Analysis of distribution laws of transformer oil indicators in 110-330 kV transformers","authors":"O. Shutenko, S. Ponomarenko","doi":"10.20998/2074-272x.2021.5.07","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.07","url":null,"abstract":"Introduction. Ensuring the operational reliability of power transformers is an urgent task for the power industry in Ukraine and for most foreign countries. One of the ways to solve this problem is the correction of maximum permissible values of insulation parameters. However, such a correction is fundamentally impossible without an analysis of the laws of distribution of diagnostic indicators in the equipment with different states. The purpose of the research is to analyse the laws of distribution of the quality indicators of transformer oil with different states in 110 and 330 kV transformers. Novelty. It was found that both 330 kV autotransformers and 110 kV transformers have the displacements between the mathematical expectations of the distribution density of usable oil indicators. It caused by different service life of the analysed transformers and different values of load factors. This indicates the need to consider the influence of these factors when correcting the maximum permissible values of oil indicators. Also, the presence of displacement between the distribution densities of some indicators of usable oil in 110 kV transformers and 330 kV autotransformers has been revealed. It indicates a different intensity of oxidation reactions in transformers with different voltage class. In order to reduce the heterogeneity of initial data the procedure of statistical processing of in-service test results has been proposed as a method. This procedure combines the use of a priori information about the service life of equipment and values of load factors with the elements of statistical hypothesis testing. The results of the analysis of the distribution laws of transformer oil indicators with different states have shown that for both usable and unusable oil the values of oil indicators obey the Weibull distribution. Values of the shape and scale parameters for each of the obtained indices arrays have been obtained, as well as calculated and critical values of the goodness-of-fit criteria. Practical value. Obtained values of the distribution law parameters of the transformer oil indicators with different states, considering the service life and operating conditions allow to perform the correction of the maximum permissible values of the indicators using the statistical decision-making methods.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42997930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-18DOI: 10.20998/2074-272x.2021.5.06
A. A. Mohamad Yusoff, K. Ahmad, S. N. Sulaiman, Z. Hussain, N. Abdullah
Introduction. Known vibrational energy harvesting methods use a source of vibration to harvest electric energy. Piezoelectric material works as a sensing element converted mechanical energy (vibration) to electrical energy (electric field). The existing piezoelectric energy harvesting (PEHs) devices have low sensitivity, low energy conversion, and low bandwidth. The novelty of the proposed work consists of the design of PEH’s structure. Air cavity was implemented in the design where it is located under the sensing membrane to improve sensitivity. Another novelty is also consisting in the design structure where the flexural membrane was located at the top of electrodes. The third novelty is a new design structure of printed circuit board (PCB). The purpose of improvised design is to increase the stress in between the edges of PEH and increase energy conversion. With the new structure of PCB, it will work as a substrate that absorbs surrounding vibration energy and transfers it to sensing element. Methods. Three techniques were successfully designed in PEH and fabricated namely PEH A, PEH B, and PEH C were characterized by two experiments: load and vibration. The load experiment measured load pressure towards the PEH, whereas the vibration experiment measured stress towards the PEH. Results. PEH C has the highest induced voltage for a weight of 5.2 kg at the frequency of 50 Hz and the highest stored voltage for a period of 4 min. The three techniques applied in PEHs were showed improvement in transducer sensitivity and energy conversion. Practical value. A piezoelectric acoustic generator was used in the experiment to compare the performance of the designed PEH with available piezoelectric transducers in the market. The new flexible membrane worked as a sensing element was worked as a cantilever beam. PVDF was used as a sensing element due to the flexibility of the polymer material, which is expected to improve sensitivity and operating bandwidth.
{"title":"Air cavity-based vibrational piezoelectric energy harvesters","authors":"A. A. Mohamad Yusoff, K. Ahmad, S. N. Sulaiman, Z. Hussain, N. Abdullah","doi":"10.20998/2074-272x.2021.5.06","DOIUrl":"https://doi.org/10.20998/2074-272x.2021.5.06","url":null,"abstract":"Introduction. Known vibrational energy harvesting methods use a source of vibration to harvest electric energy. Piezoelectric material works as a sensing element converted mechanical energy (vibration) to electrical energy (electric field). The existing piezoelectric energy harvesting (PEHs) devices have low sensitivity, low energy conversion, and low bandwidth. The novelty of the proposed work consists of the design of PEH’s structure. Air cavity was implemented in the design where it is located under the sensing membrane to improve sensitivity. Another novelty is also consisting in the design structure where the flexural membrane was located at the top of electrodes. The third novelty is a new design structure of printed circuit board (PCB). The purpose of improvised design is to increase the stress in between the edges of PEH and increase energy conversion. With the new structure of PCB, it will work as a substrate that absorbs surrounding vibration energy and transfers it to sensing element. Methods. Three techniques were successfully designed in PEH and fabricated namely PEH A, PEH B, and PEH C were characterized by two experiments: load and vibration. The load experiment measured load pressure towards the PEH, whereas the vibration experiment measured stress towards the PEH. Results. PEH C has the highest induced voltage for a weight of 5.2 kg at the frequency of 50 Hz and the highest stored voltage for a period of 4 min. The three techniques applied in PEHs were showed improvement in transducer sensitivity and energy conversion. Practical value. A piezoelectric acoustic generator was used in the experiment to compare the performance of the designed PEH with available piezoelectric transducers in the market. The new flexible membrane worked as a sensing element was worked as a cantilever beam. PVDF was used as a sensing element due to the flexibility of the polymer material, which is expected to improve sensitivity and operating bandwidth.","PeriodicalId":44198,"journal":{"name":"Electrical Engineering & Electromechanics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43311096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}