Design Of Motor Servo Control Systems Based On Industrial Ethernet

With the widely application of industrial Ethernet and fieldbus in automation field,application of industrial Ethernet to servo system has become one of the important developing trends of modern servo drivers.EtherCAT bus is widely used increasingly for its short fresh cycle,high real time capability and synchronicity.Based on the research of real-time industrial Ethernet,a set of EtherCAT communications servo drivers is designedFirstly,the background of the research and the status of servo control system are introduced.The development of industrial Ethernet technology and the impact of high-performance servo control system are presented.The main features of EtherCAT technology and the development of the status quo at home and abroad are introduced.Secondly,the mathematical model of the permanent magnet synchronous motor in the three-phase stationary coordinate and the mathematical model of PMSM in d-q coordinates are analyzed.The method of estimating the moment of inertia and the friction coefficient of the motor system is introduced.The estimation algorithm of moment of inertia and friction coefficient is compiled,and the 400W Delta motor is used as the experimental object,and the model of AC servo system is established.Thirdly,the hardware circuit of AC servo driver is designed,including the main control circuit of the system based on STM32 chip,power drive circuit,EtherCAT communication interface circuit,touch man-machine interaction circuit,etc..Fourthly,the algorithm program of AC servo driver is designed,which includes the procedure of current loop,speed loop,position loop,motor speed detection,motor rotor initial position detection,load estimation feedforward compensation and LAN9252 communication in the servo driver.Finally,a servo drive test experimental device is built based on the CoDeSys platform.The starting,loading,position tracking performance and communication performance of EtherCAT are tested.The experimental results show that the software and hardware design of servo system is correctness.