Interfering influences on electrical cable between frequency converter and electric motor

2016 ◽  
Author(s):  
Ondrej Sadilek ◽  
Tomas Lelek ◽  
Jan Korinek
Keyword(s):  
Electric Motor ◽  
Frequency Converter ◽  
Electrical Cable

scholarly journals Insulation Life Span of Low-Voltage Electric Motors—A Survey

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1738
Author(s):  
Vanessa Neves Höpner ◽  
Volmir Eugênio Wilhelm
Keyword(s):  
Life Span ◽  
Electric Motor ◽  
Low Voltage ◽  
Frequency Converter ◽  
Rate Of Change ◽  
High Rate ◽  
Switching Frequency ◽  
Electric Motors ◽  
Frequency Converters ◽  
High Switching Frequency

The use of static frequency converters, which have a high switching frequency, generates voltage pulses with a high rate of change over time. In combination with cable and motor impedance, this generates repetitive overvoltage at the motor terminals, influencing the occurrence of partial discharges between conductors, causing degradation of the insulation of electric motors. Understanding the effects resulting from the frequency converter–electric motor interaction is essential for developing and implementing insulation systems with characteristics that support the most diverse applications, have an operating life under economically viable conditions, and promote energy efficiency. With this objective, a search was carried out in three recognized databases. Duplicate articles were eliminated, resulting in 1069 articles, which were systematically categorized and reviewed, resulting in 481 articles discussing the causes of degradation in the insulation of electric motors powered by frequency converters. A bibliographic portfolio was built and evaluated, with 230 articles that present results on the factors that can be used in estimating the life span of electric motor insulation. In this structure, the historical evolution of the collected information, the authors who conducted the most research on the theme, and the relevance of the knowledge presented in the works were considered.

Research of Load Unbalance of a Two- Motor Variable Frequency Dtive for Scraper Conveyor

2021 ◽  
Vol 64 (4-5) ◽  
pp. 37-45
Author(s):  
Dmitry Shprekher ◽  
◽  
Gennady Babokin ◽  
Evgeny Kolesnikov ◽  
Dmitry Ovsyannikov ◽  
...  
Keyword(s):  
Load Balancing ◽  
Electric Motor ◽  
Frequency Converter ◽  
Common Type ◽  
Single Frequency ◽  
Variable Frequency ◽  
Electric Motors ◽  
Electric Drives ◽  
Scraper Conveyor ◽  
Simulation Results

The article analyzes the uneven loading of the scraper conveyor electric motors. The most common type of multi-motor conveyor is considered here: two-drive, with head and end drives connected through gearboxes and sprockets by an endless chain with scrapers. The simulation results are presented for three variants of com-binations of parameters of electric drives. It has been established that the use of a two-motor variable frequen-cy drive of a scraper conveyor powered by a single frequency converter inevitably entails uneven loading of the electric motors of the head and end drives. To eliminate this disadvantage, it is proposed to supply each electric motor from its own frequency converter. A system of automatic load balancing is proposed. The implementation and the result of the work of the load balancing system are carried out on a model in the Matlab / Simulink system.

A frequency converter for a propelling electric motor

2014 ◽  
Vol 85 (1) ◽  
pp. 45-52 ◽  
Author(s):  
G. M. Mustafa ◽  
S. V. Volkov ◽  
A. M. Ershov ◽  
Yu. M. Sennov ◽  
G. M. Minaev
Keyword(s):  
Electric Motor ◽  
Frequency Converter

scholarly journals The use of a digital controller in the loading system of the test bench to improve the accuracy of simulating the modes of oil pumping units

2020 ◽  
Vol 220 ◽  
pp. 01072
Author(s):  
Timur Petrov ◽  
Vladimir Kornilov ◽  
Alfred Safin ◽  
Nikita Kuvshinov ◽  
Alexey Tsvetkov ◽  
...  
Keyword(s):  
Electric Motor ◽  
Test Bench ◽  
Mechanical Load ◽  
Frequency Converter ◽  
Experimental Studies ◽  
Test Automation ◽  
Operating Modes ◽  
Automation Systems ◽  
Loading System ◽  
Pumping Units

Modern trends in the development of technologies are based on the need to conduct experimental studies of the developed equipment in laboratory conditions with the maximum approximation of operating modes to real ones. Such studies are impossible without the development of specialized stands with test automation systems. In modern test equipment systems, devices are often used to create a mechanical load on the shaft of the electric motor under study. As such a device, a system of frequency converter load asynchronous electric motor has been proposed and implemented, which has been tested at the test bench and has proven itself from the best side in comparison with traditional circuits using DC motors.

scholarly journals STARTING UP AND REGULATING THE ROTATIONAL SPEED OF A POWERFUL ELECTRIC DRIVE USING A MAGNETIC REDUCING GEAR

2020 ◽  
pp. 16-23
Author(s):  
Alexander A. Afanasyev
Keyword(s):  
Electric Motor ◽  
Permanent Magnets ◽  
Frequency Converter ◽  
Input Voltage ◽  
Magnetic Core ◽  
Stator Winding ◽  
State Equations ◽  
Current Frequency ◽  
Reducing Gear ◽  
Load Mode

The article examines a magnetic reducing gear, the stator winding of which receives power in the mode of a valve machine. In the absence of this supply, the electric motor can be started-up in no-load mode. To significantly reduce the power of the magnetic reducing gear frequency converter compared to the power of the adjustable electric motor, it is necessary to make the number of the rotor's pairs of poles with permanent magnets of a magnetic reducing gear large enough. In this case, the design of arranging the magnets in radial grooves is the most adequate, ensuring the concentration of fluxes per pole in the air gaps. The stator winding of such a magnetic reducing gear will be low-pole. When manufacturing a magnetic reducing gear, it is possible to use a stator magnetic core of a serial asynchronous machine together with its regular winding. The electromagnetic moments of the magnetic gearbox rotors are a consequence of the presence of a stator electromagnetic moment. The stator's current frequency is represented by two components, of which the first is defined from the state equations and the second is a constant forming an additional channel of functional influence. The speed of rotation of the gear shafts can be adjusted by changing the specified constant and the input voltage of the frequency converter. The equations of the magnetic reducer state describing its functional modes were solved by means of the Mathcad mathematical program.

scholarly journals Errors classification method for electric motor torque measurement

2021 ◽  
Vol 4 (1(60)) ◽  
pp. 42-48
Author(s):  
Mykola Kulyk ◽  
Volodymyr Kvasnikov ◽  
Dmytro Kvashuk ◽  
Anatolii Beridze-Stakhovskyi
Keyword(s):  
Electric Motor ◽  
Strain Gauge ◽  
High Speed ◽  
Supply Voltage ◽  
Frequency Converter ◽  
Influence Factors ◽  
Nearest Neighbors ◽  
Measuring Instruments ◽  
Maximum Deviation ◽  
K Nearest Neighbors

The use of high-precision measuring instruments for determining the torque of electric motors in such areas as medicine, motor transport, shipping, aviation requires the improvement of the metrological characteristics of measuring instruments. This, in turn, requires an accurate assessment of their error. Of particular importance is the measurement of power at high-speed installations, where in some cases conventional measurement systems are either unsuitable or have low accuracy. Thus, the use of high-speed turbomachines in aviation, transport, and rocketry creates an urgent need for the development of high-quality measuring instruments for conducting precise research. In turn, in the absence of means for accurately determining the error, attempts are made to predict them. This makes it possible to timely identify the influence of many factors on the accuracy of measuring instruments. The increase in the error arises, as a rule, through abrupt changes in the measurement conditions. Such errors are unpredictable, and their significance is difficult to predict. In the course of the study, the K-nearest neighbors method was used, to establish criteria for which a gross error may occur. The results obtained make it possible to establish threshold values at which the maximum deviation can be established under various conditions of the experiment. In a computational experiment using the K-nearest neighbors method, the following factors were investigated: vibration; temperature rise of measuring sensors; instabilities in the supply voltage of the electric motor, which affect the accuracy of the strain gauge and frequency converter. As a result, the maximum errors were obtained depending on the indicated influence factors. It has been experimentally confirmed that the K-nearest neighbors method can be used to classify deviations of the nominal value of the error of measuring instruments under various measurement conditions. A metrological stand has been developed for the experiment. It includes a strain gauge sensor for measuring torque and a photosensitive sensor for measuring the speed of the electric motor. Signal conversion from these sensors is implemented on the basis of the ESP8266 microcontroller

Comparison of Energy Indicators of the Electric Lift Drive of the Ekg-5 Excavator with Different Power Converters

2021 ◽  
Vol 64 (3) ◽  
pp. 53-59
Author(s):  
Eduard Grekov ◽  
◽  
Alexei Bezgin ◽  
Viktor Sorokin ◽  
Ildar Yamansarin ◽  
...  
Keyword(s):  
Electric Motor ◽  
Power Converters ◽  
Frequency Converter ◽  
Electric Motors ◽  
Joint Work ◽  
Two Phase ◽  
Electric Drives ◽  
Three Phase ◽  
Energy Indicators ◽  
Asynchronous Electric Motor

The energy indicators of the EKG-5 excavator lifting electric drive with thyristor power circuits have been determined according to the systems thyristor direct frequency converter - two-phase asynchronous electric motor, converter-DC motor and direct frequency converter - three-phase asynchronous electric motor. Losses in electric motors and converters have been determined, taking into account the specifics of their joint work in theefficiency for the excavation cycle were determined based on the results of calculating the simulation model, the initial data for which were the parameters of the excavation cycle of the lift drive of a real excavator. Distortion coefficients of the mains current were determined for two cases: during digging and during accelerated lowering of an empty bucket. For comparison, the energy indicators of the selected electric drives with a filter-compensating device were calculated. The analysis of energy indicators is made.

scholarly journals Measurement of Heat Losses on The Milking Machine Electric Motor at Various Regulations of Vacuum Using Methods of Thermal Imagery

2014 ◽  
Vol 62 (5) ◽  
pp. 1007-1014
Author(s):  
Jan Kudělka ◽  
Jiří Fryč ◽  
Petr Trávníček
Keyword(s):  
Specific Heat ◽  
Electric Motor ◽  
Frequency Converter ◽  
Control Valve ◽  
Ambient Air ◽  
Heat Losses ◽  
Thermal Imagery ◽  
Heat Flows ◽  
Frequency Converters ◽  
Milking Machine

To ensure the desirable vacuum in the milking machines, use is currently made predominantly of rotary vacuum pumps. These vacuum pumps are driven by a squirrel-cage induction motor. Until recently, the vacuum in the system to achieve the required value was controlled by a main control valve sucking in ambient air into the system. During the milking process itself and during other activities (flushing, sanitation), this control method consumed a large amount of electricity. The technical solution to electricity demand reduction was introduced with the emergence and development of frequency converters. The frequency converters control the operation of the asynchronous electric motor so that the actual delivery of the vacuum pumps equals the volume of air sucked into the vacuum pipe. The motor supply by the frequency converter brings about a host of adverse phenomena. This paper is dedicated to motor heating and heat losses on the surface of the electric motor at different regulations of vacuum in milking machines. The objective of the paper is to determine the immediate specific heat flows along the surface of the electric motor of the milking machine during milking using a control valve regulation and a control using the frequency converter, and compare the resulting value. The specific heat flows were determined by means of a non-traditional method of temperature field measurement using a system of thermal imagery. The calculated and measured data obtained from both these systems were statistically evaluated and compared. Use was made of a milking machine located in the cooperative Hospodářské obchodní družstvo (HOD) Jabloňov.

scholarly journals ПОДХОД К АНАЛИЗУ ЭФФЕКТИВНОСТИ РЕГУЛИРОВАНИЯ ХОЛОДОПРОИЗВОДИТЕЛЬНОСТИ СИСТЕМ КОНДИЦИОНИРОВАНИЯ ПРИТОЧНОГО ВОЗДУХА

2018 ◽  
pp. 29-33
Author(s):  
Евгений Иванович Трушляков ◽  
Николай Иванович Радченко ◽  
Вениамин Сергеевич Ткаченко
Keyword(s):  
Electric Motor ◽  
Air Conditioning ◽  
Frequency Converter ◽  
Piston Compressor ◽  
Ambient Air ◽  
Climatic Conditions ◽  
Coefficient Of Performance ◽  
Air Cooling ◽  
Refrigeration Capacity ◽  
Air Conditioning Systems

It is determined that the operation of ambient air conditioning systems (AACS) has significant fluctuations in the heat load in accordance with current climatic conditions. This makes very problematic the application of refrigeration compressors with frequency converters, which are very effective for controlling the refrigeration capacity in closed air conditioning systems, in which the temperature control range and, accordingly, fluctuations in thermal load are insignificant in comparison with the ambient air cooling. For the purpose of analyzing the efficiency of controlling the refrigeration capacity of the AACS by changing the electric motor speed of the piston compressor in current climatic conditions, the entire range of changing current thermal loads is divided into two parts according to controlling the refrigeration capacity by appling a frequency converter: the part of effective cooling capacity adjustment without energy losses (without reducing the coefficient of performance) from nominal to its threshold value and the part of reduced refrigeration capacity without its controlling by a frequency converter. It is revealed that for the warmest summer month, the proportion of refrigeration capacity spent for cooling ambient air to the temperature of 10 °C with 50 % frequency controlling the refrigeration capacity is about 10 % of the total amount of that could be produced at nominal refrigeration capacity. At higher temperatures of cooled air is even less. This shows the low efficiency of controlling the refrigeration capacity of the AACS by changing the speed of rotation of the piston compressor electric motor and the need to use other methods of controlling the refrigeration capacity. The proposed approach to analyzing the efficiency of controlling the refrigeration capacity of AACS in current climatic conditions allows not only to estimate the efficiency of refrigeration capacity controlling method but also to reveal the reserves for increasing the efficiency of applying the available refrigeration capacity

ANALYSIS OF THE OPERATION OF PUMPING UNIT UNDER A RANGE OF DIFFERENT LOADS

2019 ◽  
pp. 263-267
Author(s):  
Antoaneta Dimitrova
Keyword(s):  
Electric Motor ◽  
Energy Efficient ◽  
Frequency Converter ◽  
Hot Water ◽  
Maximum Efficiency ◽  
Pump Unit ◽  
Start Up ◽  
Different Types ◽  
Pumping Unit ◽  
Pumping Units

The report analyzes the work of a pumping unit from the hot water installation of the Faculty of Technics and Technologies - Yambol, Bulgaria, under different load conditions. Simulation stands have been adapted that are suitable for analyzing the performance of motors of different types and depending on how they are put into the pump unit. It was found that when the energy inefficient electric motor is directly started, the maximum efficiency is 79,63% and is achieved at 100% of its load. When using a frequency converter, at 100% of its load, the efficiency is 86,83%. The proposed energy-efficient electric motor, with direct start-up, has the highest efficiency of 86,7%. The obtained results can be used in the modernization of the hot water installation of the Faculty of technics and Technologies - Yambol, in the part “pumping units”.

Sign in / Sign up

Export Citation Format

Share Document