全数字交流伺服系统在工业缝纫机上的应用研究

　　全数字交流伺服系统在工业缝纫机上的应用研究
　　With the domain upgrade of rag trade, more and more traditional Industrial Lockstitch Sewing Machines (ILSM) are being replaced by the ones with computers which are good at efficiency, energy conservation and environment protection and win the favor of consumers.The servo system of ILSM with computer designed in the paper emplores TMS320LF2407A DSP of TI Corporation as the main controller which implements the servo control of Permanent-Magnet Synchronous Motor (PMSM). Field Oriented Control with I_d = 0 is applied whose torque ripples are small, and wide speed could be gained. A complex photoelectric encoder with low cost is used as Neodymium Magnets the position and detection of rotor. The endoer makes the start of PMSM easy. The samples of phase currents emplore two hall sensors which have the high precision. The current control loop and the speed loop use the anti-integration saturation PI contorller to improve the interface immunity and obtain good tracking perfomance.The system provides fast response and sufficient precision control of speed and position, and its speed is steady. It enables automatic functions such as needle positioning, automatic trimmer and wiper, backtacking, constant-stitch sewing. Besides, the system has the self-checking function and the PID controller whose parameters could be adjusted easily which improve the system’s applicability.
　　To different PMSMs, good effect of control could be gained by simple adjustment of PID controller. Self-checking of system can be used to detect the main performances of the system, such as accelerating and decelerating time, precision of position control. http://www.999magnet.com/products/110-sintered-neodymium-magnets An operation panel is designed to set the sewing parameters which are then downloaded into the DSP through the Series Communication Interface (SCI).The circuit of power driver is composed of IR21365 and IRFP460 whose safeguard ensure the safety of system. Hardware design is precise and flexible and circuits have strong ability of noise resistance.The techniques of Oriented Object Programming (OOP) and Combined Programming are emplored for the sofeware design of system to enrure the system’s real-time characteristic. It provides opportunity for advancements of the C language and the assembly language.Results of the system tests show that the control system has good performance and has bright market prospect.