Development On The Servo Drive With EtherCAT Bus

With the widely application of industrial Ethernet and fieldbus in the industrial automation field, and the development trend of digitization and networking of the servo system, the bus interface technology integrated into the servo system has become a trend in the field of industrial development in the future. EtherCAT bus is the real-time ethernet technology of flexible topology, high reliability, high transfer rate and efficiency. EtherCAT bus applys to the field of motion control. The paper conbines the EtherCAT bus technology with servo drive, researches and develops the system of EtherCAT bus servo drive.In this paper, the mathematical models of PMSM in static three-phase coordinates and in rotary two-phase coordinates are separately buit, and the vector control algorithm and SVPWM control technoly of the PMSM has made the detailed introduction.As for hardware design, this paper mainly includes the mian control circuitry based on STM32F407, the drive circuitry with IPM FSAM20SH60A as mian power switch device, and the communication module using ET1100 chip as the slave controler. It also designs the power concersion circuits, the optical couple elements circuits, the AD current sampling circuits, the sensor interface circuits and some peripheral circuits, and finishs the hardware development of servo drive system.As for software design, the system software that uses C language programming in the integrated of Keil μVision 4 is devided into three parts:the main program, the interrupt service routine and the communication program. The modularized structure is detailed introduction to every module of the subroutine which includes three resistors current sensing, SVPWM wave generation, PID controller digitization and EtherCAT communication and so on. The software design of servo drive is realized.At last, the experiment platform is built for the system of EtherCAT bus servo drive, and the software and hardware of the system is debugged. The phase voltage experiment of the motor, the experiment of SVPWM wave and the experiment of the performance are tested, and verify that servo drive system can achieve prospective object and basically meet the demand of actual application.