Motor Mode Research Articles

Power control of an autonomous wind energy conversion system based on a permanent magnet synchronous generator with integrated pumping storage

Wind energy plays a crucial role as a renewable source for electricity generation, especially in remote or isolated regions without access to the main power grid. The intermittent characteristics of wind energy make it essential to incorporate energy storage solutions to guarantee a consistent power supply. This study introduces the design, modeling, and control mechanisms of a self-sufficient wind energy conversion system (WECS) that utilizes a Permanent magnet synchronous generator (PMSG) in conjunction with a Water pumping storage station (WPS). The system employs Optimal torque control (OTC) to maximize power extraction from the wind turbine, achieving a peak power coefficient (Cp) of 0.43. A vector control strategy is applied to the PMSG, maintaining the DC bus voltage at a regulated 465 V for stable system operation. The integrated WPS operates in both motor and generator modes, depending on the excess or shortfall of generated wind energy relative to load demand. In generator mode, the WPS supplements power when wind speeds are insufficient, while in motor mode, it stores excess energy by pumping water to an upper reservoir. Simulation results, conducted in MATLAB/Simulink, show that the system efficiently tracks maximum power points and regulates key parameters. For instance, the PMSG successfully maintains the reference quadrature current, achieving optimal torque and power output. The system’s response under varying wind speeds, with an average wind speed of 8 m/s, demonstrates that the generator speed closely follows turbine speed without a gearbox, leading to efficient power conversion. The results confirm the flexibility and robustness of the control strategies, ensuring continuous power delivery to the load. This makes the system a feasible solution for isolated, off-grid applications, contributing to advancements in renewable energy technologies and autonomous power generation systems.

ЕЛЕКТРОМЕХАНІЧНІ ХАРАКТЕРИСТИКИ БЕЗКОНТАКТНОГО ДВИГУНА З ПОСТІЙНИМИ МАГНІТАМИ ПРИ ШИРОТНО-ІМПУЛЬСНОМУ ЖИВЛЕННІ

The paper is devoted to the study of the characteristics and operating modes of a brushless permanent magnet motor in the structure of an electric drive with a two-wire external power supply from a voltage source with pulse-width regulation. The dependences of the motor rotation frequency, the stator current effective value and the average value of the current in the DC link of the voltage inverter, as well as the dependences of the torque coefficient on the average value of the motor torque are given. The influence of the frequency of the pulse supply voltage on the operating modes of the motor is studied. The current and torque limitation modes of the motor in a system with a single-position relay controller and a fixed transistor shutdown interval former are studied. Ref. 12, fig. 16.

Performance study of integrated compressor/expander based on small-scale compressed air energy storage system

Compressed air energy storage will have good development prospects because of its exceptional safety and reliability, low economic cost, zero carbon emissions, and pollution-free environmentally friendly characteristics, which meet the needs of sustainable and green development. In view of the problems of large volume, great number of equipment, and poor flexibility of traditional compressed air energy storage equipment, this article built a compressed air experimental bench based on pneumatic motor and conducted integrated pneumatic motor compression/expansion experiments. The effects of key parameters such as speed, torque and current on the performance of pneumatic motor under different modes are investigated, providing reference for the application and promotion of small compressed air energy storage systems. The results indicate that in the expansion mode of the pneumatic motor, the total efficiency and power output of the motor can reach up to 14.01 % and 1257.87 W. Its high power output and economic operation are concentrated within the medium range of rotation speed and current, respectively, with a certain cooling effect achieved in this mode. In compression mode, the maximum output power of the motor can reach 3696.33 W, while the energy efficiency is up to 78.39 %. The operating parameters such as torque and current are basically positively correlated with the system performance parameters. The integrated system is flexible, saves space, and has certain feasibility.

Comprehensive assessment of factors affecting the operational reliability of low-voltage asynchronous electric motors of a coal mining complex

THE RELEVANCE of this study lies in solving the problem of reliable functioning of elements of energy systems and ensuring their effective operation during open-pit mining. The paper presents a methodological approach that allows us to assess the level of reliability of low-voltage asynchronous electric motors in a coal mine with complex mining, geological and climatic conditions of production. THE PURPOSE of the work is to quantify the operational factors affecting the service life of an asynchronous electric motor with a short-circuited rotor. Attention is focused on how influencing factors, different in physical basis, among which electrical parameters are highlighted – the coefficient of voltage asymmetry in the reverse sequence, the coefficients of harmonic voltage components and environmental parameters – temperature, air humidity and dustiness, affect the dynamics of changes in the service life of an asynchronous electric motor. Asynchronous electric motors used at one of the enterprises of JSC SUEK in the Trans-Baikal Territory are considered as an object of research. METHODS. The main tool for the implementation of research tasks is computer modeling based on the Matlab software package. RESULTS. The studies were performed on an asynchronous electric motor with a short-circuited rotor with Ph = 3 kW, rated speed 1500 rpm. The simulation of the operating mode of the electric motor under study was performed by changing the experimental parameters: the values of the total coefficient of harmonic voltage components (KU) – from 4 to 12% with a range of 2%; the values of the voltage asymmetry coefficient in the reverse sequence (K2U) – from 0 to 4% with a range of 1%; the ambient temperature (∆Tокr) – from -30°C to +30°C with a range of 10°C; air humidity values (Vc) – 20% and 60%; dust thermal conductivity coefficient values (Kт) – 0,12 and 0,28. Based on the obtained research results, diagrams are constructed that clearly illustrate the dynamics of changes in the service life of an asynchronous electric motor depending on the combination of influencing factors. CONCLUSION. The trends in solving the issues of reliable functioning of a coal mining enterprise with the presence of asynchronous electric motors and ensuring their efficient operation are the most priority, mainly focused on maintaining the stability of technological processes and maintaining the production volumes of a coal mining enterprise. The stability of the electric motor to certain influencing factors is estimated and their critical values are established. Recommendations on the use of asynchronous electric motors are formulated, taking into account their operating conditions.

Optimization of the Operation of Thermal Power Plants Based on the Use of Motor Mode

Optimization of the Operation of Thermal Power Plants Based on the Use of Motor Mode

Self-starting of induction motors at non-sinusoidal power source voltage

Subject of research: the process of self-starting of asynchronous electric motors in the presence of higher harmonics in the supply voltage network. Purpose of research: analysis of the influence of non-sinusoidal voltage on the duration of self-starting of asynchronous motors and the amount of additional heating during self-starting. Methods and objects of research: modeling of the self-starting mode of an asynchronous motor in the coordinate system α, β, 0; simulation modeling in Matlab Simulink. Main results of research: it has been shown that failure to take into account higher harmonics when the total harmonic distortion (THD) limit values are reached can result in an error in determining the self-start time by more than 20 % and the heating temperature by more than 10 %.

Structure of software and hardware module for research of DC electrical machines. Part 1

The structure of a hardware and software complex for the study of DC electric machines and a mathematical model of its electromechanical part taking into account the influence of temperature on the resistance of the armature winding have been developed. The hardware and software complex is implemented on the Arduino Uno board. A distinctive feature of which is the modular structure, which allows conducting research on DC electric machines in various operating modes (start-up, armature speed control, reversing, braking). In addition, it is possible to implement various laws of changing the load moment. For this purpose, the hardware and software module include the studied and load DC electric machines, which are mechanically connected to each other by means of a coupling and operate in motor and generator modes, respectively. The proposed model makes it possible to describe electromagnetic processes in DC electric machines taking into account the influence of temperature on the resistance of the armature winding, as well as overheating of individual parts of the electric machine. The proposed hardware and software module can find practical application in research laboratories in the study of DC electric machines in various operating modes.

Progressive gray matter atrophy in parkinsonian variant of multiple system atrophy assessed by using causal structural covariance network.

Multiple system atrophy (MSA), a rare neurodegenerative disease, is usually accompanied by brain morphological alterations. However, the causal relationships between progressive gray matter atrophy in MSA parkinsonian (MSA-P) subtype remain unknown. In total, thirty-five MSA-P patients and thirty-five healthy controls (HC) underwent three-dimensional high-resolution T1-weighted structural imaging and voxel-based morphometry analysis. The causal structural covariance network (CaSCN) of gray matter was assessed to explore the causal relationships in MSA-P. With greater illness duration, the reduction of gray matter was originated from right cerebellum and progressed to bilateral cerebellum, fusiform gyrus, insula, putamen, caudate nucleus, frontal lobe, right angular gyrus, right precuneus, left middle occipital lobe and left inferior temporal lobe, then expanded to midbrain, bilateral para-hippocampus, thalamus, temporal lobe, inferior parietal lobule (IPL), precentral gyrus, postcentral gyrus and middle cingulate cortex. The right cerebellum was revealed to be the core node of the directional network and projected positive causal effects to bilateral cerebellum, caudate nucleus and left IPL. MSA-P patients showed progression of gray matter atrophy over time, with the right cerebellum probably as a primary hub. Furthermore, the early structural vulnerability of cerebellum in MSA-P may play a pivotal role in the modulation of motor and non-motor circuits at the structural level.

Students' self-assessment of the optimality of individual motor modes

Students' self-assessment of the optimality of individual motor modes

Experimental study on the power generation characteristics of a free piston engine generator prototype with dual linear generator modules

The dual-piston dual-cylinder free piston engine generator (DD-FPEG) has garnered significant attention for its high thermal efficiency, power density, and suitability for various fuels. To improve performance and stability, this paper proposes a DD-FPEG prototype integrating dual linear generator (LG) modules. The structure and working process of the prototype is introduced, followed by testing its operating characteristics and power generation performance from the cold start to power generation process. When LG1 operates in motor mode, and LG2 operates in generation mode with no load, the motor thrust must exceed 126 N to ensure piston movement. As the motor thrust decreases from 221 N to 0 N and then switches to generation mode, the peak cylinder pressure, operating frequency, output voltage and power show a decreasing trend. The coefficients of variation for peak cylinder pressure position, top and bottom dead center positions are lower than that of peak cylinder pressure, and their values are below 3 %. When the load is 50 Ω, the prototype operates at about 31.2 Hz, with an average indicated power of 1422.8 W and a peak output power of about 1002.5 W. These results demonstrate that the proposed control strategy enables the designed prototype to achieve stable operation and smooth switching.

Neural Net Monitoring of the Non-Stationary Mode of an Asynchronous Motor

Neural Net Monitoring of the Non-Stationary Mode of an Asynchronous Motor

Examining the Effect of Noninvasive Brain Stimulation on Hemispheric Lateralization of Motor Learning During a Functional Fine Motor Task

Abstract Date Presented 03/23/24 This study explores how noninvasive brain stimulation of the left and right posterior parietal cortex influences bilateral fine motor control. Results suggest distinct effects on speed and accuracy to help understand fine motor control modulation. Primary Author and Speaker: Sydney C. Sharp Additional Authors and Speakers: Brooke Dexheimer

Исследование сигнала внешнего магнитного поля асинхронного электродвигателя в режиме выбега

Currently, one of the important scientific tasks is the development and improvement of methods for non-destructive testing of asynchronous electric motors during operation. One of the promising areas of diagnostics is the use of an external magnetic field signal. However, its study in the run-down mode is not given due attention by the authors of scientific publications, despite a number of advantages of this signal. Therefore, the aim of this research is to confirm the possibility to record and study the signal of the radial component of the induction of the external magnetic field in the run-down mode of an asynchronous motor. So, the aim is relevant. The research is carried out using several test benches, real low-voltage and high-voltage asynchronous motors and a simulation model of an asynchronous electric motor designed in the Ansys software package. To process the signals, namely, to construct the frequency-time spectra of the external magnetic field in the run-down mode, the authors have used a program based on the Short Time Fourier Transform using the Flat-top window as a window function to more accurately determine the amplitudes of the harmonic components. During the research conducted on test benches, it has been found that the external magnetic field of the motor in the run-down mode will exist due to the phenomenon of residual magnetization. The possibility of modeling asynchronous motors considering residual magnetization has been proven and the reliability of the resulting model has been confirmed. The spectra of external magnetic field signals on real motors and simulation models in the run-down mode are presented. The external magnetic field signal in the run-down mode can be recorded both on simulation models and on real low-voltage and high-voltage asynchronous electric motors. During further research, it is planned to analyze the possibility of identifying faults in asynchronous motors using this signal.

Stability Assessment of an Ore Mill Electric Drive Using Machine Learning

The relevance of the study is due to the need to improve electric drive systems operated in harsh conditions. The goal of the study is to create a model for assessing the state of stability of the electric drive of an ore mill using machine learning capabilities, which will provide high performance and the ability to work consistently in different systems. Various sustainability assessment models have been developed based on 6 machine learning algorithms. The study and comparison of models built using artificial neural networks (ANN) of different architectures was carried out using various learning methods. The expediency of using the Tree and ANN algorithms to develop a model for assessing electric drive stability is substantiated. The novelty of the results obtained lies in the fact that the model has high accuracy, high speed, and the ability to detect instability in uncertain operating modes of the electric motor of an electric drive, as well as the possibility of coordinated operation with various systems. The practical value is that the model allows, at an intellectual level, to provide effective control and fault diagnosis of complex electric drive systems, which cannot be achieved using the known methods. Doi: 10.28991/HIJ-2024-05-02-01 Full Text: PDF

Consensus Paper: Cerebellum and Reward.

Cerebellum is a key-structure for the modulation of motor, cognitive, social and affective functions, contributing to automatic behaviours through interactions with the cerebral cortex, basal ganglia and spinal cord. The predictive mechanisms used by the cerebellum cover not only sensorimotor functions but also reward-related tasks. Cerebellar circuits appear to encode temporal difference error and reward prediction error. From a chemical standpoint, cerebellar catecholamines modulate the rate of cerebellar-based cognitive learning, and mediate cerebellar contributions during complex behaviours. Reward processing and its associated emotions are tuned by the cerebellum which operates as a controller of adaptive homeostatic processes based on interoceptive and exteroceptive inputs. Lobules VI-VII/areas of the vermis are candidate regions for the cortico-subcortical signaling pathways associated with loss aversion and reward sensitivity, together with other nodes of the limbic circuitry. There is growing evidence that the cerebellum works as a hub of regional dysconnectivity across all mood states and that mental disorders involve the cerebellar circuitry, including mood and addiction disorders, and impaired eating behaviors where the cerebellum might be involved in longer time scales of prediction as compared to motor operations. Cerebellar patients exhibit aberrant social behaviour, showing aberrant impulsivity/compulsivity. The cerebellum is a master-piece of reward mechanisms, together with the striatum, ventral tegmental area (VTA) and prefrontal cortex (PFC). Critically, studies on reward processing reinforce our view that a fundamental role of the cerebellum is to construct internal models, perform predictions on the impact of future behaviour and compare what is predicted and what actually occurs.

ЖАЛПЫ БІЛІМ БЕРЕТІН МЕКТЕП ОҚУШЫЛАРЫНЫҢ ҚОЗҒАЛЫС БЕЛСЕНДІЛІГІН ЗЕРТТЕУ

Research by scientists shows that the modern way of life in the family and the organization of the educational process at school does not provide the biological need for the school body to move. The daily motor activity of elementary school students decreases by 50 percent compared to preschoolers, and high school students - by 75 percent. The lack of motor activity of schoolchildren leads to a decrease in the level of physical fitness. The reform of general education and vocational schools has set new tasks for the entire education system to improve the educational process and educate the younger generation.The article examines the motor mode of secondary school students. When conducting pedagogical observations and a questionnaire survey, the characteristic features of the manifestation of children's motor activity during the day, changes in the volume of activity against the background of daily activities, the proportion of dynamic and static loads coming to the body and background energy consumption of children were taken into account. The physical fitness of the students was determined during physical education lessons based on the results of the test tasks: running speed for various distances and strength exercises. The indicators of height, weight, dynamometry, motor and strength indicators were studied. Based on the results of the research, methodological recommendations have been developed for physical education teachers and parents. The purpose of these recommendations is to provide the most accessible, physiological substantiation material for the preparation of a training program.

Pre-optimization-assisted deep reinforcement learning-based energy management strategy for a series–parallel hybrid electric truck

P2-P3 series-parallel hybrid electric vehicles (HEVs) feature intricate topologies with multiple power sources and multiple working modes, posing a challenge for developing effective energy management strategies (EMSs). This paper introduces a framework that combines deep reinforcement learning (DRL) with pre-optimized energy management to address this challenge. Considering the characteristics of HEVs, the framework incorporates the pre-optimized equivalent motor and pre-optimized mode selection rule into a deep deterministic policy gradient (DDPG) loop. The pre-optimization of the equivalent motor aims to reduce the energy management task’s dimensionality by equating two motors as the equivalent motor, while the pre-optimized mode selection rule systematically integrates mode selection and energy allocation into the EMS. The study assumes HEVs operate in connected urban environments and incorporates middle-horizon traffic information to enhance EMS performance. Additionally, the study integrates the frequent engine start-stop characteristics of HEVs into EMS design. Simulation results demonstrate that the fuel economy of the proposed EMSs in this study ranges from 87.2% to 90.7% of the DP-based EMS. The inclusion of an engine start-stop penalty significantly reduces the number of engine start-stops without compromising fuel economy.

Research Status of New Energy Vehicle Thermal Management

Thermal management of new energy vehicles, as a way to break through the driving range of new energy vehicles and one of the guarantees of safety performance, has been paid more and more attention to. In order to improve the thermal management efficiency of new energy vehicles, the thermal management mode of the whole vehicle should be optimized, so that different parts can work at a suitable temperature, so as to ensure the functional safety and service life of the vehicle. Based on this, this paper analyzes the passenger cabin thermal management system through Positive Temperature Coefficient (PTC) heating air conditioning, heat pump air conditioning and other technologies. This paper introduces the new energy vehicle battery thermal management system from the aspects of direct cooling mode and heating mode, introduces the battery thermal management system through the analysis of flow charts, and introduces the cooling mode of electric control and motor, and pays attention to some cutting-edge research progress, and summarizes the automobile thermal management technology theory.

Devising a technique for assessing the accuracy of measuring electric motor torque

The object of this study is a technique for assessing the accuracy of measuring the torques of electric motors. This technique is based on the improvement of dynamic torque measurement processes under transient operating modes. Special attention was paid to devising adaptive methods to normalize the output signal, which take into account vibrations and nonlinearities of the measuring channel. In order to improve the accuracy of measurements under conditions when the controlled parameter has different deviations from its average value, a technique for integrating time measurement intervals was proposed. That has made it possible to generalize parameter fluctuations, providing more stable measurement results. This paper reports the simulation of the process of measuring torques of electric motors under transient operating modes and under vibration conditions. That has made it possible to test the proposed technique for estimating the variance of the methodological error, which includes the integration of measurement time intervals and makes it possible to increase the accuracy of the measurement under the conditions of transient modes in electric motor operation. An algorithm for correcting the error of the dynamic torque of the electric motor has been proposed, which allows it to be corrected. This becomes possible owing to the use of a reference measure and the proposed technique for determining the deviations of the controlled parameter of the measured quantity, as well as the automatic calibration of measuring transducers. The algorithm allows for flexible settings of the corrective action, expanding the potential of electric motor control systems. It can complement soft measurement methods, as well as adjust the threshold values of deviations under different operating modes of electric motors. This allows the measured systems to better adapt to changes in operating conditions, to adjust the specified measurement accuracy under conditions of uncertainty

Motion Learning for Musculoskeletal Robots Based on Cortex-Inspired Motor Primitives and Modulation

Motion Learning for Musculoskeletal Robots Based on Cortex-Inspired Motor Primitives and Modulation