scholarly journals Utilization of Two Sensors in Offline Diagnosis of Squirrel-Cage Rotors of Asynchronous Motors

Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6573
Author(s):  
Petr Kacor ◽  
Petr Bernat ◽  
Petr Moldrik

In the manufacture squirrel-cage rotors of asynchronous motors, a high standard of quality is required in every part of the production cycle. The die casting process usually creates porosity in the rotor bars. This most common defect in the rotor often remains hidden during the entire assembly of the machine and is usually only detected during final testing of the motor, i.e., at the end of the production process. This leads to unnecessary production costs. Therefore, the aim is to conduct a continuous control immediately after the rotor has been cast before further processing. In our paper, we are interested in selecting a suitable method of offline rotor diagnostics of an asynchronous motor that would be effective for these needs. In the first step, the selection of the method and its integration into the overall manufacturing process is carried out. The arrangement of the sensors and their calibration is then simulated on a 2D Finite Element Model of the rotor. The proposed offline measurement procedures and technologies are finally validated by testing measurements on a rotor that simulates the most frequently occurring faults. A test system is also developed that provides the operator continuous information about the running rotor measurements and makes it easier to evaluate the quality of the cast rotor by means of graphical visualization of the faults.

2019 ◽  
Vol 139 ◽  
pp. 01053
Author(s):  
Victoria Romanova ◽  
Sergey Khromov

Issues of operating modes of 4A series asynchronous squirrel-cage motors and AI serried motors at asymmetrical supply voltage for different values of motor shaft load are considered on the basis of simulation using Matlab software package and Simulink package. In the simulation, currents in asynchronous motor phases were evaluated as a function of K2U, KZ, and based on these results, permissible operation parameters were evaluated for induction motors. The results obtained are the basis for technical solutions aimed at improving operational reliability of asynchronous motors, they will allow taking into account permissible operating parameters of asynchronous motors not only in the design, but also in operation in power supply systems of various facilities.


2013 ◽  
Vol 401-403 ◽  
pp. 308-311 ◽  
Author(s):  
Miao Shang ◽  
Guo Min Lin ◽  
Qiang Hua Guo ◽  
Yong Tao Sun

The boot method of three wound-rotor asynchronous motors and three-phase squirrel-cage asynchronous motor are described; As to reduce the start current and to increase the starting torque, the principle of all kinds of startup methods are analyzed; the advantages and disadvantages of various starting methods are evaluated; Development directions of modern motor startup are pointed out.


2020 ◽  
Vol 17 ◽  
pp. 00124
Author(s):  
Elena P. Polikarpova ◽  
Igor E. Mizikovskiy

Modern science and practice does not have a sufficient set of cost management tools, taking into account the duration of the production cycle, characteristic of agricultural activity. The implementation of a cycle-oriented approach to building a model of production costs was based on studying the existing options for classifying production costs, which were supplemented with features from the perspective of managing long production cycles. As a result of the study, a model of production costs was built from the point of view of a cycle-oriented approach, as well as a model of production costs from the standpoint of features of a long production cycle. The model can serve as the basis for the formation of the information space of cost management, control and cost analysis in the economy of agricultural enterprises.


Author(s):  
S.Yu. Trudnev ◽  

The most widely used single-phase asynchronous motors are described and also substitution and vector dia-grams are reviewed. Theoretical and mathematical descriptions of processes of controlling and enabling asynchronous modes of operation were provided, on the basis of which computer models of a single-phase asynchronous motor in static and dynamic modes was created in the Matlab program. Experiments were per-formed on the real and virtual models, and the data obtained were processed and compared to confirm the adequacy of the developed virtual model.


2019 ◽  
Vol 104 ◽  
pp. 01006
Author(s):  
Maxim Filimonov ◽  
Nicolay Karnaukhov ◽  
Eugeny Lukyanov ◽  
Dmitry Smyatsky ◽  
Roman Mironenko

this article the energy efficient frequency way of starting of production mechanisms electrical drive with low power asynchronous motors (from 90 Wt to 5 kWt) is proposed. To provide this With the goal of electrical losses decreasing during asynchronous motor starting the Pontryagin Maximum Principle have been applied by the authors when analysing of two-mass model of production mechanism frequency controlled electrical drive. In result of calculations for frequency controlled electrical drive of production mechanism with 90 Wt power asynchronous motor of the model 4AA50A2 Dependencies of amplitude and frequency of supply voltage by the time are obtained. These dependencies confirm possibility of decreasing the electrical power losses with different values of motor shaft load torques. In compare with the other ways of asynchronous motor starting (for example U/f=const) they allow to decrease the electrical losses more then two times in nominal mode.


2021 ◽  
Vol 12 (1) ◽  
pp. 689-700
Author(s):  
Ao Lei ◽  
Chuan-Xue Song ◽  
Yu-Long Lei ◽  
Yao Fu

Abstract. To make vehicles more reliable and efficient, many researchers have tried to improve the rotor performance. Although certain achievements have been made, the previous finite element model did not reflect the historical process of the motor rotor well, and the rigidity and mass in rotor optimization are less discussed together. This paper firstly introduces fractional order into a finite element model to conduct the harmonic response analysis. Then, we propose an optimal design framework of a rotor. In the framework, objective functions of rigidity and mass are defined, and the relationship between high rigidity and the first-order frequency is discussed. In order to find the optimal values, an accelerated optimization method based on response surface (ARSO) is proposed to find the suitable design parameters of rigidity and mass. Because the higher rigidity can be transformed into the first-order natural frequency by objective function, this paper analyzes the first-order frequency and mass of a motor rotor in the experiment. The results proved that not only is the fractional model effective, but also the ARSO can optimize the rotor structure. The first-order natural frequency of asynchronous motor rotor is increased by 11.2 %, and the mass is reduced by 13.8 %, which can realize high stiffness and light mass of asynchronous motor rotors.


2020 ◽  
Vol 318 ◽  
pp. 01050
Author(s):  
Konstantinos Tsongas ◽  
Gabriel Mansour

The objective of this paper is to evaluate the vibration isolation performance of an elevator motor mounted on elastomeric nanocomposite mounts. A series of conventional acrylonitrile-butadiene rubber (NBR) mounts have been reinforced with 20wt% concentration of multi-walled carbon nanotubes (MWCNTs). The vibration isolation capacity of the machine mounts was calculated through the transmissibility of an elevator motor test system. A Finite Element Model (FEM) was introduced and a harmonic analysis based on the ANSYS code has been utilized to investigate the modal behavior of the nanocomposite machine mount/elevator motor system and extract a representative model of the vibrational behavior. The cyclic compression results have revealed that the stiffness and damping capacity of the conventional elastomers can be modified by adjusting the proportion of MWCNTs. Elastomers’ vibration isolation performance of the motor was ameliorated with the inclusion of MWCNTs, signifying that the enhancement of the elastomers with MWCNTs was rather effective. The vibration level of the elevator motor was decreased to 90% by incorporating the optimal concentration of MWCNTs in NBR mounts.


2019 ◽  
Vol 14 (2) ◽  
pp. 77-82
Author(s):  
Рустам Аипов ◽  
Rustam Aipov ◽  
Рустам Галиуллин ◽  
Rustam Galiullin ◽  
Раушан Нугуманов ◽  
...  

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.


2006 ◽  
Vol 519-521 ◽  
pp. 1461-1466 ◽  
Author(s):  
André Larouche ◽  
Malcom Lane ◽  
Massimo DiCiano ◽  
Daan M. Maijer ◽  
Steve CockCroft ◽  
...  

Horizontal continuous casting process has been successfully implemented in Alcan for the production of T-ingots of primary aluminium and foundry alloys. Ability to achieve increased productivity targets and reduce production costs relies on a fundamental understanding of key process characteristics and operating parameters. Thanks to the long-standing experience in vertical DC Casting, numerical modelling appeared as a powerful approach to understand phenomena related to metal flow, solidification and ultimately defect formation. As part of a collaborative R&D program, a global model of horizontal casting process, integrating specialized sub-models on critical aspects of the process such as meniscus dynamics, is being developed. Experimental characterization of primary and secondary cooling is performed in parallel with modelling work to provide the information necessary to properly characterize mould heat transfer. This paper will present the development of a 3D process model of T-ingot casting along with its application to solve specific process challenges that have emerged during the first years of production in the plant.


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