三维扫描振镜动态聚焦控制系统建模与仿真

Modeling and Simulation of Dynamic Focusing Control System for 3D Scanning Galvanometer

摘要: 三维扫描振镜动态聚焦系统是激光三维加工的核心部件，动态聚焦系统实时补偿离焦误差的出现克服了传统二维扫描系统由于扫描范围增大，光程差存在导致聚焦面为球面且聚焦光斑不均匀性和不能加工三维立体表面等现象。目前市场上的动态聚焦控制系统研究较少，且大都存在着速度慢、响应慢和精度低等缺陷，不能满足新型行业及高端领域的应用需求。本文针对扫描式激光振镜打标系统平台设计了动态聚焦控制系统，首先基于电机平衡方程建立双电机的动力学数学模型；其次在电机模型基础上添加电流环、速度环、位置环三闭环PID控制并采构建动态聚焦控制系统simulink仿真模型；最后应用仿真模型对实际电机性能进行1%阶跃响应以及正弦跟踪响应验证，控制仿真模型与实际控制系统匹配度较好，满足三维高速激光加工需求，为高速高响应动态聚焦控制系统的控制性能研究提供了新的思路。

Abstract: The dynamic focusing system of three-dimensional scanning galvanometer is the core component of laser three-dimensional processing. The dynamic focusing system compensates the defocusing error in real time, which overcomes the phenomenon that the traditional two-dimensional scanning system has spherical focus surface and uneven focus spot due to the increase of scanning range and optical path difference. There are few researches on dynamic focusing control system in domestic market, and most of them have the defects of slow speed, slow response and low precision, which cannot meet the application needs of new industries and high-end fields. In this paper, the dynamic focusing control system is developed for the scanning laser galvanometer marking system platform. Firstly, the dynamic mathematical model of the double motor is established based on the motor balance equation. Secondly, the current loop, speed loop and position loop PID control are added to the motor model, and the Simulink simulation model of the dynamic focusing control system is built. Finally, the simulation model is applied to the actual motor. It can verify the 1% step response and sinusoidal tracking response, and the control simulation model matches well with the actual control system, which meets the requirements of 3D high-speed laser processing. It provides a new idea for the control performance research of high-speed and high response dynamic focusing control system.