scholarly journals Stop ModeSimulation for an Asynchronized Vent Motor Fed by a Voltage Inverter

2020 ◽  
Vol 20 (3) ◽  
pp. 132-136

The paper presents the results of mathematical modeling of a sensorless electric drive control system operation. This system is based on a dependent voltage inverter with current phase control and phase-locked loop frequency control and feeds an asynchronous valve motor in the stop mode. The article presents the developed model of this electric drive in the MATLAB mathematical modeling system. The model features an excitation frequency converter, that maintains a nominal rotor current and a constant excitation frequency of 15 Hz. From the stator (armature) side, the frequency converter is synchronized in phase with the current using an automatic frequency control unit and sets the phase angle between the current and the armature voltage. The paper presents a basic system of equations that describes the modes of operation of an asynchronized valve motor, as well as the expression of the electromagnetic moment in the stop mode. It shows the electromagnetic torque on the motor shaft, which was obtained as a result of mathematical modeling of the thrust mode of an asyn­chronized valve motor at rated currents, the rotor frequency of 15 Hz, with 20 electrical degrees phase shift between the current and the armature voltage.

Author(s):  
Sergey Grigoryevich Cherniy ◽  
Aleksandr Sergeevich Sobolev ◽  
Pavel Andreevich Erofeev

The paper describes a variable frequency drive which consists of two elements: an electric drive (synchronous or asynchronous electric drives, that is, drives powered by alternating current are used in capacity of it), and a frequency converter able to control the amplitude and frequency of the voltage supplied to the drive. It becomes possible to control the speed of rotation of the electric motor and the torque on its shaft. The most optimal energy efficiency when using compressor units is achieved under the operating mode when its average daily load factor makes at least 85%. Under the mentioned operating mode fluctuations during the compressed air consumption will be minimal, and the most stable operation of the compressor at its rated nominal power is ensured. In practice, no more than 15% of all the industrial compressors are operated in such operating mode. For 85% of the compressor units the question of improving energy efficiency by regulating its capacity remains open. The method of capacity regulation by using a frequency converter is currently the most optimal and perfect, because adjusting the parameters of the electric drive in this way, the most accurate regulation of the compressed air pressure is provided, which allows reducing the energy consumption in the compressed air injection process, as well as extending the service life of the equipment used. There has been considered a device with frequency control of a compressor unit, debugging of which was carried out on the basis of a mathematical model, which allows choosing the most optimal parameters for frequency control of an electric drive of a compressor unit in order to increase energy efficiency. The analysis of all the advantages and disadvantages of frequency regulation is being carried out, as well as a comparative analysis for selecting the optimal frequency converter in terms of the import substitution


Author(s):  
V. N. Meshcheryakov ◽  
D. S. Sibirtsev ◽  
S. Valtchev ◽  
E. I. Gracheva

THE PURPOSE. In controlled AC drives used on continuous-action mechanisms, which include conveyors, conveyors, cranes, the most widespread are asynchronous motors with a phase rotor, controlled mainly along the rotor circuit using various regulators with low energy efficiency. To improve the energy efficiency of an electric drive based on ADFR, it is proposed to develop a control system that combines the principles of frequency control of the motor along the stator circuit and powering the rotor circuit with constant voltage, which allows the electric drive to be considered synchronized. METHODS. The presence of a DC link in the frequency converter makes it possible in principle to connect the rotor winding in series to this link. However, in order to ensure the frequency principle of regulating the output characteristics of the electric drive, it will be necessary to regulate the rectified current at the input of the inverter and, accordingly, in the rotor windings, which will require a significant change in the standard control system of the frequency converter. The use of an additional adjustable switch in the DC link is proposed. RESULTS. The study of the proposed non-standard control system for a frequency asynchronous synchronized electric drive was carried out by the method of simulation modeling in the Matlab Simulink software package. CONCLUSION. A control system for a frequency asynchronous synchronized electric drive has been developed and investigated on a computer model. A correction system is proposed that allows maintaining a constant value of the load angle in the starting mode. The scalar system of relay frequency control of the electric drive is supplemented with vector correction of the variables, which makes it possible to continuously provide the necessary mutual orientation of the stator current vectors and the rotor flux linkage.


Author(s):  
V. N. Meshcheryakov ◽  
D. S. Sibirtsev ◽  
S. Valtchev ◽  
E. I. Gracheva

THE PURPOSE. In controlled AC drives used on continuous-action mechanisms, which include conveyors, conveyors, cranes, the most widespread are asynchronous motors with a phase rotor, controlled mainly along the rotor circuit using various regulators with low energy efficiency. To improve the energy efficiency of an electric drive based on ADFR, it is proposed to develop a control system that combines the principles of frequency control of the motor along the stator circuit and powering the rotor circuit with constant voltage, which allows the electric drive to be considered synchronized. METHODS. The presence of a DC link in the frequency converter makes it possible in principle to connect the rotor winding in series to this link. However, in order to ensure the frequency principle of regulating the output characteristics of the electric drive, it will be necessary to regulate the rectified current at the input of the inverter and, accordingly, in the rotor windings, which will require a significant change in the standard control system of the frequency converter. The use of an additional adjustable switch in the DC link is proposed. RESULTS. The study of the proposed non-standard control system for a frequency asynchronous synchronized electric drive was carried out by the method of simulation modeling in the Matlab Simulink software package. CONCLUSION. A control system for a frequency asynchronous synchronized electric drive has been developed and investigated on a computer model. A correction system is proposed that allows maintaining a constant value of the load angle in the starting mode. The scalar system of relay frequency control of the electric drive is supplemented with vector correction of the variables, which makes it possible to continuously provide the necessary mutual orientation of the stator current vectors and the rotor flux linkage.


2018 ◽  
Vol 41 ◽  
pp. 03006
Author(s):  
Ziyodullo Eshmurodov ◽  
Folib Holboiv

The article shows the peculiarity of the system of technological automation of the newest Simatic S7-1500 PLCs, for electric drives of hoisting transport machines, the analysis of control systems for electric drives of operating mine hoisting machines of mining complexes. One of the main ways to increase the energy efficiency of MLM is to replace old asynchronous electric motors with a phase rotor with squirrel cage induction motors designed for operation in a frequency-controlled electric drive. The introduction of a frequency converter and an electric drive control system, which together allow the recovery of electricity in the supply network in the mode of generator braking. Thus, the system for automated control of the mine hoisting machine based on the Simatic S7-1500 PLC, with the developed control algorithm, is an integrated energy-efficient control system, which it is advisable to use in the management of the SHM.


Author(s):  
T. V. Sinyukova ◽  
V. N. Meshcheryakov ◽  
A. V. Sinyukov

THE PURPOSE. To investigate the existing methods of frequency control and their influence on the characteristics of the asynchronous motor, including the energy parameters. Consider new circuit solutions of the control type under study. Create a mathematical model of each of the methods of frequency control. To analyze the results obtained from the point of view of the behavior of mechanical, electromechanical and energy components. METHODS. When solving this problem, the method of computer simulation modeling, implemented by means of Matlab Simulink, was used. RESULTS. In this paper, various aspects of electric drive systems based on asynchronous motors with the use of cascade switching are studied and described, existing connection schemes for such systems are analyzed, and several new options with improved characteristics are proposed. A comparative analysis of various connection schemes is made, the most interesting results of such analysis are presented, and conclusions are drawn about the future prospects of certain circuit solutions.Electric drive systems were modeled in the Simulink MATLAB environment using software tools to demonstrate the operation parameters of the considered circuits. CONCLUSION. Various schemes for switching on the asynchronous motor in the Simulink Matlab environment were investigated. The results of the study revealed the potential usefulness of using a circuit with a transformer in the rotor circuit, as well as the construction of a multi-motor electric drive with a common transformer and a common frequency converter circuit. The efficiency of parallel connection of rotary circuits of a two-motor electric drive was demonstrated. The methods of returning the sliding energy to the network are also compared, and their effectiveness in a comparative analysis with the operation in the closed-loop rotor mode is demonstrated.


2021 ◽  
Vol 15 (3) ◽  
pp. 48-54
Author(s):  
A. P. Sporov ◽  
D. Yu. Pisarev ◽  
A. S. Parakhnich

Abstract. The authors showed the relevance of creating agricultural machines using an electric drive. (Research purpose) The research objective is to develop an experimental prototype vehicle using an electrical schematic diagram of charge and electric drive control. (Materials and methods) The VAZ 111 Oka car was chosen as an experimental vehicle model with an electric drive, since it has a light weight of 645 kilograms, a simple design and a low cost. Mechanical characteristics of the electric motor were calculated and a frequency converter was chosen to control the electric drive.  Laboratory bench tests were conducted. (Results and discussion)The authors   installed storage batteries to power the electric drive, developed an electrical circuit schematics getting charged from a 220 volt alternating voltage network, and received graphs for the discharge of a 40-storage-battery power supply. (Conclusions) An electrical schematic diagram of charge and electric drive control was developed and implemented on an experimental vehicle model. It was determined that at the electric motor continuous operation with the load current of 1 ampere, the batteries get discharged within 104 minutes;  with the current  load of 2 amperes, they get  discharged within 83 minutes; with 3 amperes – within 65 minutes, and with 5 amperes – within 50 minutes, which is enough to drive around the farm. The authors graphically depicted the dependence of the available capacity level on the voltage, as well as the batteries’ discharge on the time at various load currents. The authors carried out two experimental studies on storage batteries’ charging from alternating voltage with the current of 2 and 3 amperes: in the first case, the charging time was 350 minutes, in the second – 310 minutes. It was found out that when using the developed scheme, the batteries are charged evenly.


2020 ◽  
Vol 178 ◽  
pp. 01021 ◽  
Author(s):  
Victor Meshcheryakov ◽  
Dmitry Sibirtsev ◽  
Ekaterina Mikhailova

At the end of the last century asynchronous motors with a phase rotor were most widely used among adjustable-speed AC drives. They were used for conveyors, transporters, cranes. That was due to the relative simplicity to adjust the motor speed by acting on the rotor chain. The introduction of a frequency control method in such drives is now complicated by the fact that most frequency converters are designed to be used in drives with a cage asynchronous motor. Shorting of a phase winding leads to highly increased losses during acceleration and motor speed control. If the stator winding of a wound-rotor asynchronous motor is connected to a frequency converter and the rotor winding is connected to a DC link of this converter, the motor will have properties of a synchronous one. The electric drive is able to work in a wide range, while motor characteristics are absolutely rigid. The implementation of such control method is presented in this article. The control system operation has been tested with simulation in the Matlab Simulink software pack. The obtained results are defined as follows.


Author(s):  
B. I. Firago ◽  
S. V. Aleksandrovsky

As compared to asynchronous frequency-controlled electric drives, synchronous drives are characterized by lower power losses, rigid mechanical characteristics without speed feedback and by the simplest law of frequency control (when the voltage changes proportionally to the frequency). An analytical study of energy factors (power loss, efficiency, power factor) of frequencycontrolled synchronous motor with electromagnetic ignition and with excitation caused by permanent magnets has been fulfilled. The efficiency of the power converter, in this case (i. e. in the case of the frequency converter), depends on the structure of the converter (single-link or two-link), on the power semiconductor devices being used, on additional elements (i. e. chokes, capacitors, transformers, active resistance, etc.). The efficiency of a synchronous electric motor (which is a cofactor of general efficiency of a controlled synchronous electric drive) is of an interest in the scalar frequency control of the mentioned synchronous motor, since there are almost no publications on this subject. Therefore, the energy conversion efficiency of the synchronous motor, which receives energy from the frequency converter at different frequencies and converts to mechanical energy, has been considered. For the convenience of analytical research, we used the widely used concept of relative frequency as the ratio of the current value of the voltage frequency to the nominal one. It is demonstrated that the maximum efficiency is shifted in the direction of a lower load factor with a decrease in the relative frequency of the motor supply voltage. The method of calculating the energy performance of variable frequency synchronous motor that has been developed is illustrated by the graphs of efficiency and cosj for the engine of the SD3 13-34-6 type of the capacity of 500 kW and of a voltage of 6 kV and for a synchronous motor with permanent magnets of the YGT132S4 type of a capacity of 5.5 kW.


2013 ◽  
Vol 333-335 ◽  
pp. 2323-2326
Author(s):  
Min Li Yu ◽  
Yan Jun Bi ◽  
Hong Xiu Meng

A kind of portable digital storage oscilloscope (DSO) is developed in this paper. It builds trigger, storage, measurement module for embedded system with programmable logic resource of FPGA chip. The external digital circuits of a digital oscilloscope is achieved. And it saves a lot of cost by implanting NIOS II soft-core processor as the control unit of the system in the FPGA. This system has the function of automatic frequency control (AFC) and automatic gain control (AGC), and it can measure the signal conveniently.


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