The Research On Servo Driver And Its Communicate Technology

Numerical control system, the most important application area of servo motor, is now demanding more specific qualities for servo systems. As a result, designing of servo system should take full consideration of the development direction of the NC system and its demands for servo system. As the NC systems are getting more and more complicated, in order to adapt to the market demand, NC systems are becoming more and more open. A lot of open NC systems are built up based on the Windows operating system, and this arise a serious problem inevitably. Windows operating system is not a real-time OS, and NC system has a lot of real-time tasks to do, how to resolve this contradiction? As NC systems always have more than one axis, their must be more than one servo motor to control, so another problem which can not be ignored is that how to synchronize these servo control systems in Windows OS.In this thesis, a novel servo control system is been raised, which can solve the two problems above to some extend. The servo control system used USB2.0 protocol to communicate with the host computer. This thesis also built a vector decoupled control model of PMSM. According to this model, this thesis designed a servo control system based on DSP+FPGA framework. In this framework of DSP+FPGA, the primary closed loop control blocks are carried out in DSP, and the algorithm of space vector PWM (SVPWM) are carried out in FPGA. Besides the SVPWM, the algorithms which are carried out in FPGA also including speed sensor, position sensor, coordinate transform, etc. This thesis also designed an A/D board with high speed and high precision to measure the current of the armatures in PMSM. The servo control system reserved several interfaces on its PCB for future functional extension. Among them, the interface for SDRAM makes it possible for transfer massive command data.