叶片精密抛光伺服系统的干扰观测补偿控制

叶片型面尺寸精度及表面质量的提高对数控抛光伺服系统性能提出了更高的要求.针对非线性摩擦和被控对象参数摄动对数控抛光伺服系统定位精度和跟踪精度的影响,提出了一种基于干扰观测器的粒子群优化模糊PID(PFPID)控制方法.该方法通过构造干扰观测器来预测伺服系统中的非线性摩擦和参数摄动等各种干扰,并在控制中引入等效的补偿来抑制干扰,同时利用粒子群优化算法对模糊控制器的量化因子和比例因子进行在线调整,进而利用模糊控制器对PID控制参数进行自适应整定.仿真分析和实验结果表明,基于干扰观测器的PFPID控制器具有控制精度高、鲁棒性强、抑制干扰能力强等优点,其能够提高叶片型面尺寸精度和表面一致性,降低表面粗糙度,减小残余应力并提高抛光效率.

Compensation Control of Blade Precision Polishing Servo System Based on Disturbance Observer

With the improvement of blade profile dimensional precision and surface quality, higher re- quirement is put forward for the performance of CNC polishing servo system. According to the influence of nonlinear friction and parameter perturbation on the positioning and tracking precision of the CNC polis- hing servo system, a particle swarm optimization fuzzy PID （PFPID） control method based on disturbance observer was proposed. This method could predict nonlinear friction, parameter perturbation and other in- terference in the servo system by constructing a disturbance observer, and the equivalent compensation was introduced to suppress the interference. Simultaneously, the particle swarm optimization algorithm was used to adjust the quantization factor and proportional factor of the fuzzy controller, and then the fuzzy controller was used to tune the PID control parameters adaptively. Simulation analysis and experimental results show that with such advantages as high control precision, strong robustness and great interference suppression ability, the PFPID controller based on disturbance observer can improve blade profile dimen- sional precision and surface consistent, reduce surface roughness, decrease residual stress and improve polishing efficiency.