Industrial Sewing Machine With Ac Servo Control System Research And Development

The expanding of the clothing, footwear and caps trades is promote the sewing machine industry to develop rapidly. Along with the application of new advanced technologies, intellectualized multifunction sewing machine is gradually becoming the development trend of sewing machine. Servo and control system is the core of the intellectualized multifunction industry sewing machine. On the basis of sufficient study of system structure, the features and functions of the servo control system applied to the industry sewing machine, the AC servo control system using a small inertia Permanent Magnet Synchronism Motror was researched and designed in this thesis.In this thesis, three closed-loops, which include current loop, speed loop, position loop, are designed to make the servo system obtain a performance of rapid responsing and precisely positioning. A current loop based on integral partition PI control method, a speed loop based on non-liner PID control method, as well as the accurate positioning method were designed and introduced in the thesis. To improve the servo qulity of the system, the dead-time effect and its influence with PMSM inverter is analyzed and a current observer based on Kalman Filter was designed inαβ0 frame, and the dead-time effect was compensated according to the error voltage.Microchip's 16-bit high performance Digital Signal Controller (DSC) and Mitsubishi's forth generation Intelligent Power Module (IPM) are used in the hardware platform as the core components. The control board circuit, power inverter and power supply was designed. The filter ciruit, isolating circuit and various protective circuits are realized as well to enhance the reliability and the stability of the hardware.The software system was designed based on the Finite State Machine structure in order to lower the coupling degree among the modules of the software, and to fancilitate the development, debugging, maintenance and extension of the software system.Automatic functions such as needle positioning, automatic trimmer, wiper, bartacking, constant-stitch sewing and presser lifting are realized. Many tunable parameters are provided to improve flexibility. The test result shows that the technical performances entirely meet the design requirements and the result of plant probation shows that the servo control system has bright market prospect.