scholarly journals Relay regulation control system in frequency converter based on self-commutated voltage inverter

2015 ◽  
Vol 2 (2) ◽  
pp. 30-34
2021 ◽  
Vol 4 (46) ◽  
pp. 6-6
Author(s):  
Alexander Saakian ◽  
◽  

The regulation of the coolant speed during convective drying in a stationary grain layer allows the maximum use of the amount of heat energy for drying the material. The paper presents the results of a study of the regulation of the coolant speed on an experimental drying plant for use in the automatic control system of a chamber grain dryer. The article also discusses the issues of energy saving efficiency in drying chambers. The possibility of automatic control of the main parameters control system using a microcontroller is analyzed. Keywords: DRYING MODES, DRYING ZONE, AUTOMATIC CONTROL, TEMPERATURE CONTROLLER, FAN, OPTIMIZATION, MICROCONTROLLER, FREQUENCY CONVERTER


2013 ◽  
Vol 278-280 ◽  
pp. 1417-1422
Author(s):  
Jin Lan Zhang ◽  
Qian Lv

This paper designs a PLC automatic control system in stone cutting. The author elaborated the stone cutting process, the system hardware/software design and the human-machine interface design process. This system is the collection of PLC, sensing detection, frequency converter, configuration control technology and advanced stone cutting process in an organic whole. The author designed optional automatic/manual function and parameters setting screen. The author added limit current protection and position protection, and designed function of automatic detecting cooling water shortage to protect the saw blade from damage. Also the designed equipment can automatic light and bell for alarm. Operation results show that, this system can meet the designed requirement, and can remarkably improve the quality of stone processing. This designed control system has high machining accuracy, high intelligence, full automation, perfect protection, friendly man-machine interface and simple operation.


2014 ◽  
Vol 624 ◽  
pp. 465-468 ◽  
Author(s):  
Mei Fang Wan

This article designs one constant pressure water supply system based on PLC. In this system, PLC and frequency converter is the main control system. Moreover, the water-supply system with a variable frequency and constant pressure is based on PCL and combines with water supply pump, pressure gage and other equipment. Water supply system realizes the water supply of constant pressure and variable flow.


Author(s):  
Evgeniia Burdilna ◽  
Sergii Serhiienko ◽  
Oleksiy Chornyi

Purpose. Synthesis of an automatic control system for an asynchronous electric drive of a grain thrower conveyor based on a frequency converter with vector control. Methodology. The research was carried out using methods of mathematical modeling of an electric drive; using methods of tuning optimization and regulator synthesis. The technique of synthesis of vector control systems is based on the representation of a non-stationary multi-connected object, which is an AC machine, in the form of a set of stationary subobjects with linear links in the main control channels. Findings. The study of the work of the subordinate regulation system, which implements the principles of vector control, oriented along the vector of the rotor flux linkage, has been carried out. The modeling of the processes of AM excitation, AM start-up at idle speed, nominal load surge, speed reduction has been carried out. It was found that the synthesized system is characterized by good quality indicators. The overshoot at start does not exceed 5%, the regulation time is 0.4 s, the torque limitation is carried out at a predetermined level. It has been proven that oscillatory processes in transient modes with significant torque surges with classical settings of loop regulators can be compensated by introducing artificial cross-links into the control part of the electric drive. Originality. A system of subordinate regulation of the blood pressure of the grain thrower trimmer conveyor has been implemented to set the speed of the grain flow with the aim of throwing grain at a given distance by creating an appropriate ballistic flight trajectory, which ensures a reduction in losses from damage to grain. Practical value. The structure of the vector control system of a frequency-controlled asynchronous electric drive with additional compensating cross-connections between active and reactive energy control channels is proposed to improve the quality indicators of the system.


10.5219/1342 ◽  
2020 ◽  
Vol 14 ◽  
pp. 750-758
Author(s):  
Boris Kapovsky ◽  
Alexander Zakharov ◽  
Marina Nikitina

This article presents the theoretical aspects of developing a control system for the processing of frozen raw meat by cutters in automatic mode. The method for analytical calculation of the productivity rate of meat cutting by a cutter with a screw tooth provides an accuracy for which relative error does not exceed 6%. The authors show automatic process control in minced meat production using a control system computer (CSC), with the aim of building an automatic control system (ACS) for chopping raw materials frozen in the form of blocks. The task of ACS synthesis was solved: the system structure and its elements were chosen, the topology of their cause-and-effect relationships and an algorithm of control devices were developed, and their parameters were determined. The ACS’s control loop scheme for raw material cutting speed was realized, where an assembly of devices was chosen as the object of management (OM): the squirrel cage induction motor (SCIM) of the cutting mechanism drive; the frequency converter (FC) of the supply voltage, which changes the rotation speed of the SCIM (the rotation speed of the milling cutter); and the milling cutter of the chopper. The shaping filter method was used, to predict the size of the meat chips produced, to modulate the perturbation acting on the system from the load side. Based on the single-stage chopping of raw meat, an automatic line is created for producing meat products, with a minced meat quality management system based on artificial intelligence on the principle of ‘unmanned technology’.


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.


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