轴向主动磁轴承的改进不完全微分PID控制

摘要

为了减少电磁轴承控制中测量噪声的干扰，提高电磁轴承控制的稳态精度，以立式电机的主动控制电磁轴承为研究对象，分析了测量噪声对传统PID控制的影响，并针对一阶不完全微分PID控制和传统PID控制不能满足系统控制性能要求的情况，提出一种基于二阶不完全微分 PID控制的改进算法。采用 MATLAB的Simulink搭建了仿真模型，利用C语言和磁轴承控制平台进行了算法的试验验证。仿真和试验结果表明，改进的算法能够改善磁轴承系统的静态性能，气隙的稳态误差约为20μm，比传统PID、带一阶滤波器的不完全微分PID减小了约50％（30μm），证明了该算法的有效性。%In order to reduce the interference of measurement noise and improve the steady-state precision of magnetic bearing control,the active magnetic bearing of a vertical motor was adopted to analyze the influence of measurement noise on the traditional PID control. Considering that the incomplete derivative PID controller with the first-order filter and the traditional PID controller cannot meet the requirement in performance of controlling the measurement noises,an improved algorithm for the incomplete derivative PID control with the second-order filter was proposed. A simulation platform was then built in Simulink of MATLAB,and the improved algorithm was verified experimentally on the active magnetic bearing platform using C programming language. Results of simulation and experiments show that the improved algorithm can improve the static performance of the magnetic bearing. Using the incomplete derivative PID controller with the second-order filter,the steady-state error of the air gap of the magnetic bearing was about 20 μm,reduced by nearly 50%(i. e. ,30 μm in magnitude) compared to the traditional PID controller and the incomplete derivative PID controller with the first-order filter. This proves the effectiveness of the improved algorithm.