Design And Application Of Control System Of High Power Motor For Oxygen Generator

This paper is based on the transformation project of air compressor motor control system of 35000m~3/h oxygen making unit in an enterprise.The original control system has many faults and is difficult to start,which is no longer suitable for the current production needs.The purpose of this project is to design a set of variable frequency soft start system for air compressor,to meet the production needs of the main air compressor of oxygen generating unit which can start quickly and realize economic operation.This article first from the basic structure of synchronous motor,introduces the principles,types of one by one,and then put forward the two kinds of basic control mode of synchronous motor,particularly with respect to the manner of self-operated control analysis and its advantages and disadvantages of three kinds of different schemes,determine the renovation project adopts synchronous motor control system for cross-straight-to pay current commutation synchronous motor load system.Secondly,the existing problems of the original unit and the electric control system are analyzed,and the reconstruction scheme is put forward.The commutation mode of thyristor circuit and its deficiency and the mechanical characteristics of the modified motor are analyzed in detail.Then according to the principle block diagram,the software and hardware required by the system are analyzed and designed.The hardware system mainly designs location and speed detection scheme,current detection circuit,rectifier circuit and inverter side trigger logic.All these designs provide guarantee for the stable operation of the motor.Finally,the control system software is designed.The soft start operation scheme is given,the PI adjustment control design,digital trigger program flow design and control system simulation analysis are carried out for the system,and the operation effect of the motor before and after modification is analyzed.