基于FPGA的两相步进电机细分驱动电路设计

在采用步进电机驱动的机构中,为了提高定位精度,提出了一种基于FPGA的两相步进电机细分驱动电路的设计方案.采用正弦/余弦细分方案,通过嵌入cos/sin表格于FPGA中,合理控制步进电机两相绕组的电流,实现斩波恒流均匀细分驱动,减小了步距角、提高了步进分辨率,最高细分达到256.给出了FPGA软件设计,并在Modelsim中完成了仿真.仿真结果表明,分频、定时,正弦/余弦函数以及全桥控制信号,都可以由FPGA准确无误地产生,达到了设计的要求,取得了满意的效果.在实际的应用中,电机运行平稳.

Design of Two-phase Microstepping Driver Based on FPGA

An approach of micro step driver based on FPGA for two-phase step motor was proposed to improve the position accuracy.By applying sin/cos micro step method and adjusting the current in each winding of step motor via built-in cos/sin look-up table in FPGA,chopping constant-current and homogeneous micro step drive can be achieved,the step angles was reduced,and the step resolution was improved.The highest resolution was 256.Software design and simulation for FPGA logic in Modelsim were represented.The results show that frequency dividing,timing,cosf/sin function and control signals of full bridge can be generated accurately by FPGA.In experiments,the step motor operates as expected.