Mathematical model of an asynchronous machine in real coordinates of state

A mathematical description of an asynchronous machine with unreduced parameters in the space of real phase coordinates is given. When studying an asynchronous motor in a dual power supply system with controlled converters in rotor and stator circuits, there is a need for an AM model without parameters, in which the processes in the stator and rotor circuits will correspond to reality in magnitude. In addition, such a model is necessary when analyzing the energy parameters of the whole electric drive controlled by the rotor. To observe real processes in the stator and rotor, the model should be designed in separate spatial coordinate systems. In reference books for AM with a wound rotor (WR), as a rule, the real parameters (resistances, currents and voltages) of the stator and rotor and the voltage reduction coefficient ( ke ) are given. Bringing currents and resistances (inductances) is carried out by coefficients ki=ke and kr=ke2 respectively. Let's consider the description of the machine without reduction of parameters. For the convenience of further consideration, let's introduce the general value of the mutual inductance. We obtain an equation for the electromagnetic moment in real coordinates. Let's design a model in the MATLAB dynamic modeling environment using vector-matrix representation. Matrix algebraic operations with vector variables are implemented by Matlab Fn blocks, which are the calls to userdefined functions described in the form of M-files. The content of Matlab Fn functions is considered. On the model, the processes of starting of an AM with a phase rotor of AK-52-6 type were. Shows the graphs of start-up transients. The processes in the obtained model coincided with the results of modeling of this engine in the model with the coordinates reduced to the rotor. Thus, the energy processes described by this model correspond to the processes to the model with the given parameters, and the processes of currents and flux linkages changing of the stator and rotor are real. The model designed in the MATLAB/Simulink dynamic modeling environment can be used to study double-powered asynchronous electric drives.

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Сhoosing the Belt Conveyor Start Mode

Electrotechnical Systems and Complexes ◽

10.18503/2311-8318-2019-2(43)-54-59 ◽

2019 ◽

pp. 54-59

Author(s):

Vladimir P. Metelkov ◽

Yakov L. Liberman

Keyword(s):

Asynchronous Motor ◽

Conveyor Belt ◽

Tension Control ◽

Dynamic Loads ◽

Electric Drives ◽

Start Up ◽

High Tension ◽

Control Devices ◽

The Cost ◽

The Magnetic Field

The paper is concerned with the problems associated with starting a long conveyor driven by an induction motor. We consider the dynamic loads in the conveyor belt during start-up, which cause slippage of the conveyor belt on the traction drum leading to its premature deterioration. The relevance of the topic is associated with the high cost of the conveyor belt reaching 60% of the cost of the entire conveyor and more. The aim of the work is to ascertain the possibilities of reducing the wear of the conveyor belt, for example, through the use of the possibilities provided by the system of the electric drive. The possibility of reducing the probability of the conveyor belt slippage by increasing the initial belt tension is noted. However, constant high tension also accelerates belt deterioration. To solve this problem, the use of automatic tension control devices is proposed, as well as the reduction of dynamic loads in the belt by using soft starters based on a thyristor voltage converter, which regulates the amplitude of voltage on the motor stator. The features of an asynchronous motor heating when starting with a constant speed of rotation of the magnetic field are discussed. The interrelation between the start-up duration and the motor stator winding heating with the dynamic loads occurring in the conveyor belt in start-up modes is considered. Modeling results obtained using the Simulink package are presented. Since long start-up modes of asynchronous electric drives based on thyristor voltage converters can lead to motor overheating, especially when the conveyor is restarted under full load and in hot climates, it is advisable to use automatic conveyor belt tension control devices during start-up modes thereby reducing premature belt deterioration together with a decrease in the conveyor motor heating.

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Investigation of transitional processes of vibration machine with inertionic vibrator and asynchronous motor

System technologies ◽

10.34185/1562-9945-2-133-2021-11 ◽

2021 ◽

Vol 2 (133) ◽

pp. 97-109

Author(s):

Dmytro Kononov ◽

Viktor Yermokratiev ◽

Yevhen Miroshnyk

Keyword(s):

Experimental Data ◽

Differential Equations ◽

Nonlinear Differential Equations ◽

Asynchronous Motor ◽

Oscillation Amplitude ◽

Mining Industry ◽

Stable Operation ◽

Vibration Machine ◽

Start Up ◽

Quality Of Products

Strict compliance with technological requirements in the production of steel is one of the main factors that determine the quality of products. In the mining industry, at metallurgical enterprises and transport hubs, all kinds of vibrating machines are widely used, and in particular vibrating conveyors (VTM): vibrating conveyors, vibrating conveyors and feeders, vibrating screens and screen feeders, and vibratory loaders. The main type of drive of such machines is an inertial drive, which consists of unbalanced vibrators. This drive is simple and has been widely used in vibrating machines of various types. To ensure stable operation (constancy of the oscillation amplitude when changing any system parameters) of such a vibrating machine with an inertial drive, a resonant setting is used. In this regard, there are difficulties that arise during start-up and run-out of the vibrating feeder: increasing the amplitude of oscillations, load on the foundation, power consumption, which leads to the fact that the motor does not reach rated speed and fails during start-up. Purpose: to study the dynamics of transients in VTM, which accompany the start of VTM from rest and run. The idea of the work is computer simulation of VTM dynamics based on numerical integration of a system of nonlinear differential equations describing the motion of a machine. As well as comparing them with experimental data. A mathematical model of VTM has been developed, differential equations of VTM motion have been compiled taking into account the characteristics of an induction motor. To solve the system of differential developed a program in the application Simulink. The obtained dependences confirm the increase in the amplitude of oscillation of the VTM tray when empty and stop VTM, which must be taken into account to calculate the parameters of the systems with vibrating machines. The experimental data are compared with the calculated ones, there is a good coincidence of results.

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FLAT ASYNCHRONOUS ELECTRIC DRIVE OF STONE MILL

Vestnik of Kazan state agrarin university ◽

10.12737/article_5d3e16a42b0fb2.23635568 ◽

2019 ◽

Vol 14 (2) ◽

pp. 77-82

Author(s):

Рустам Аипов ◽

Rustam Aipov ◽

Рустам Галиуллин ◽

Rustam Galiullin ◽

Раушан Нугуманов ◽

...

Keyword(s):

Asynchronous Motor ◽

Rotation Frequency ◽

Point Of View ◽

Working Zone ◽

Electric Drives ◽

Belt Drives ◽

Asynchronous Electric Drive ◽

Asynchronous Motors ◽

Longitudinal Edge ◽

Flour Production

In modern flour production, the preservation of all vitamins and minerals in it is relevant. Minerals and vitamins are stored in flour, ground from whole grains. In the stone mills, the grain is subjected to repeated exposure to the working surfaces of the millstones, as a result of which the flour contains a large percentage of the most important components of the grain. The stone mill’s drive should provide a low rotational speed of the mills (peripheral speed up to 10 m/sec.) and the possibility of smooth control of its speed and torque without reducing the performance of the mill. From this point of view, it is promising to use in the mill’s drive, instead of asynchronous motors, rotation with additional devices (gearboxes, belt drives, V-belt drives, etc.) of flat asynchronous electric drives. The article suggests possible variants of technical solutions for stone mills with flat electric drives. It was concluded that the use of a flat asynchronous motor in the mill’s drive allows not only smoothly adjusting the frequency and torque of the millstones, but also because of the presence of edge effects, to prevent flour sticking in the millstone working zone. Compiled with the possibility of solving by analytical methods a mathematical model of mill’s drive, based on a flat electric drives, taking into account the longitudinal edge effect, the strength of viscous (internal) and dry (external) friction. The mechanical characteristics of the drive were found when moving the flat electric drives inductors and the dependencies of the change in the mill productivity on the millstone rotation frequency when grinding various grains, changing the fill factor of the grinding zone and the gap between the millstones were obtained.

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Acquisition of Higher Order Knowledge by a Dynamic Modeling Environment Based on the Educational Concept of Self-Regulated Learning

Intelligent and Adaptive Educational-Learning Systems - Smart Innovation, Systems and Technologies ◽

10.1007/978-3-642-30171-1_16 ◽

2013 ◽

pp. 393-416

Author(s):

Stefanie A. Hillen

Keyword(s):

Dynamic Modeling ◽

Higher Order ◽

Self Regulated Learning ◽

Modeling Environment ◽

Educational Concept ◽

Regulated Learning

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Dynamic modeling of high temperature PEM fuel cell start-up process

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2014.09.095 ◽

2014 ◽

Vol 39 (33) ◽

pp. 19067-19078 ◽

Cited By ~ 15

Author(s):

Y. Wang ◽

D.U. Sauer ◽

S. Koehne ◽

A. Ersoez

Keyword(s):

High Temperature ◽

Fuel Cell ◽

Dynamic Modeling ◽

Pem Fuel Cell ◽

Start Up ◽

High Temperature Pem

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Performance identification of the asynchronous electric drives by the spectrum of rotor currents

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v10.i1.pp211-218 ◽

2019 ◽

Vol 10 (1) ◽

pp. 211 ◽

Cited By ~ 2

Author(s):

Vladimir L. Kodkin ◽

Aleksandr Sergeevich Anikin ◽

Aleksandr A. Baldenkov

Keyword(s):

Frequency Control ◽

Asynchronous Motor ◽

Industrial Robots ◽

High Tech ◽

Current Feedback ◽

Electric Drives ◽

Sensorless Vector Control ◽

Torque Generation ◽

Harmonic Components

<span>The efficiency of analyzing the rotor currents of asynchronous electric drives with frequency control is substantiated in the article. To assess the quality of torque generation in the engine it is suggested to use the spectral analysis of these currents and the fundamental harmonic, as the most accurate "conformity" of slip in an asynchronous motor. The proposed method showed that "sensorless vector" control leads to the appearance of high-frequency harmonics with significant amplitude. Because of these harmonics, a non-sinusoidal electromagnetic moment is created and the performance of the drive is decreased. The most effective method of torque generation is the frequency control with positive stator current feedback. This control is dominated by pronounced harmonic components, which indicates the proximity of this structure to linear and significantly better controllability of the drives, which makes promising their use in high-tech mechanisms, in particular, in industrial robots. Simulation and experiments confirm the proposed theoretical propositions.</span>

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Computer-based model of asynchronous electric propulsion drive with three stator windings

TRANSACTIONS OF THE KRYLOV STATE RESEARCH CENTRE ◽

10.24937/2542-2324-2021-1-395-132-140 ◽

2021 ◽

Vol 1 (395) ◽

pp. 132-140

Author(s):

I. Kalinin ◽

Keyword(s):

Mathematical Model ◽

Electric Power ◽

Electric Propulsion ◽

Frequency Converter ◽

Asynchronous Motor ◽

Electric Power System ◽

Propulsion System ◽

Stator Windings ◽

Phase Coordinates ◽

Computer Based

Object and purpose of research. This paper discusses electric propulsion system of leader icebreaker. Its purpose was to develop mathematical and computer-based model of electric propulsion drive powered by asynchronous motor with three stator windings for further investigation of steady, transitional, asymmetric and emergency operation scenarios of electric power and propulsion system for the leader icebreaker. Materials and methods. Hardware and methods for computer-based simulation of complex engineering structures. Main results. Development of the mathematical model representing asynchronous motor with three windings in phase coordinates. Computational studies on direct startup of 15 MW propulsion motor, as well as on steady and transitional operational conditions of ship electric power system consisting of 36 MW synchronous genset, two-winding transformers and electric propulsion drive with 15 MW asynchronous motor in phase coordinates with three stator windings and three-level frequency converter. Calculation of voltage non-sinusoidality ratio for MSB buses with operation of 15 MW propulsion motor driven by 36 MW synchronous genset. Conclusion. Mathematical model of asynchronous motor suggested in this paper could be used to calculate steady and transitional operation scenarios of marine power systems with frequency-controlled three-winding asynchronous motor, as well as to calculate electromechanical and electromagnetic processes and refine frequency control algorithms. This is especially relevant because each of the asynchronous electric machines used in the electromechanical assemblies of leader icebreaker propulsion motors has three stator windings, and this icebreaker is the first experience of applying a 15 MW marine electric drive.

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Imitation Modeling of an Inter-Turn Short Circuit of an Asynchronous Motor Stator Winding for Diagnostics of Auxiliary Electric Drives of Transport Infrastructure

Communications - Scientific letters of the University of Zilina ◽

10.26552/com.c.2021.2.c65-c74 ◽

2021 ◽

Vol 23 (2) ◽

pp. C65-C74

Author(s):

Sergey Goolak ◽

Juraj Gerlici ◽

Oleg Gubarevych ◽

Tomáš Lack ◽

Mikhail Pustovetov

Keyword(s):

Short Circuit ◽

Asynchronous Motor ◽

Ac Impedance ◽

Transport Infrastructure ◽

Stator Winding ◽

New Approach ◽

Electric Drives ◽

Imitation Modeling ◽

Asynchronous Motors ◽

Diagnostic Complex

A scientific approach to calculating the parameters and characteristics of an asynchronous motor in the inter-turn short circuit mode in one phase of the stator is proposed to create the foundations of a diagnostic complex for assessing the condition of asynchronous motors of the transport infrastructure. This approach consists of the fact that in the model with which the research is carried out, it is proposed to take into account changes in the mutual inductance of the motor when the AC impedance of one of the stator phases changes. Using a new approach to modeling processes occurring in an asynchronous motor during the inter-turn short circuit in one phase of the stator, pulsations of the torque on the motor shaft were studied for different values of the AC impedance and resistance of one of the stator winding phases, which corresponds to varying degrees of the inter-turn short circuits.

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