Application Of AC Frequency Conversion For Speed Adjustment Controlled By PLC In Materials Milling System

With the development of electric electron technology and controlling technology, AC frequency conversion for speed adjustment technology is used widely in many fields.Because of the characteristics with high dependability , modularization structure and easy programming , PLC is used to do real-time gathering,controlling and communicating with transducer.Configuration software is often used as platform to implement the needing of users .we can design excellent human-machine windows to control the equipment with configuration software on PC.In this system ,we need to adjust the speed of electromotor .In order to make full use of energy and satisfy the need of production, considering the adjustment of speed, starting, running and braking. We use the MM 6SE92 of Siemens transducer whose functions of adding or decreasing speeding with high S form and torque promoting can solve the adjustment of speed and starting. In this system , PLC is used to collect data from fields and control equipments such as electromotor and transducer.Because the STEP7/Win32 as S7 200 PLC's programming software adopts the modularization design method of structure and code reusing, subsequently decrease the explorement and maintenance of software.By the virtue of HMI and strong communication ability, User can browse the flowchart of production adjust the speed of electromotor,faultdiagnose,start and stop the electromotor.This paper firstly introduce the meaning of subjects.summarize the development of configuration software technology, PLC technology and AC frequency conversion for speed adjustment.In the second chapter ,we introduce the structure of transducer arithmetic of controlling ,Basic principle and the advantage of AC frequency conversion for speed adjustment.In the third chapter, we introduce the structure, characteristic flowchart of data disposal of configuration software in detail and particularly introduce theSiemens protocol/pro on windows.In the forth chapter , we introduce the structure and flowchart of PLC and introduce particularly the Siemens S7 200 PLC and characteristics of software design.In the fifth chapter, we introduce the structure , the configuration of hardware and the implement of software in this system .The Last chapter, we summarise the article and prospect technology correlatively.