INVESTIGATION OF COMPRESSOR START-UP OF CONE DRILLING RIG WITH CURRENT LIMITING FUNCTION

The article deals with the problem of investigation of the system "soft starter- induction motor" for compressing equipment of cone drilling machine. Also refined mathematical model of the system, taking into account the behavior of compressor load, as well as existing working algorithm of the stator current control block is developed. The problems of choice of starting mode of compressing equipment are considered, the necessity of full research of the electric drive system with the methods of numerical modeling is determined. The basic parameters which have to be specified and corrected by the designer of the electromechanical system of the compressor during equipment commissioning are determined. Further, an algorithm for firing angle control of power thyristors, which used in modern soft starters, produced by WEG Company, is implemented. After that, the simulation of the procedure for starting the compressor induction motor using thyristors soft starter with the stator current limiting function is performed. As a result of modeling using application Simulink of software environment ATLAB, the graphs of transients for the most important working parameters, such as stator windings current, shaft rotation speed, load torque and firing angle for thyristors are obtained. The analysis of the obtained results, as a result of which formulated the conclusions on the possibility of using soft starters for the cone drill rig compressors is made. It has been determined that in the case of almost linear behavior of compressor load, the motor starts with a smooth change of speed without significant fluctuations of electric motor stator currents. It is proposed to use the current limiting function for easy starting modes and current control functions with an initial kick of torque.