永磁直线电机扰动估计与补偿的位置反步控制

由于永磁直线同步电机直接驱动负载,负载突变、摩擦力和推力波动等各种干扰也将无缓冲地直接作用于电机动子上,如果不加以考虑,将会严重影响伺服系统的精度.为了克服不确定性扰动给永磁直线同步电机位置伺服系统带来的不良影响,提出一种鲁棒反步控制策略.首先,对永磁直线同步电机的数学模型进行分析,将负载阻力、推力波动和摩擦力等作为总干扰;然后,设计一种观测器对总干扰进行估计,将干扰的估计值引入到反步控制律中,起到对扰动进行补偿的作用,并利用Lyapunov函数分析系统的稳定性;最后,通过与不带扰动补偿的反步控制进行仿真比较,结果表明所提出的控制策略能够有效消除不确定性扰动对系统的影响,增强伺服系统的鲁棒性,提高电机位置的跟踪精度.

Backstepping control of disturbance estimation and compensation for permanent magnet linear motor

Due to direct drive load of permanent magnet linear synchronous motor, various disturbances such as sudden load changes, friction and thrust fluctuations will also act directly on the motor mover without buffering. If not considered, the accuracy of the servo system will be seriously affected. In order to solve the adverse impact of the uncertain disturbance on the position servo system of the permanent magnet linear synchronous motor, the paper proposes a kind of robust backstepping control strategy. Firstly, the load force, thrust fluctuation and friction force are taken as total disturbance after analyzing the mathematic model of the permanent magnet linear synchronous motor. Then, the paper designs a kind of observer to estimate the total disturbance. The estimated value is introduced into the backstepping controller as a role of compensation of the disturbance. The paper also uses Lyapunov function to analyze the stability of the system. Finally, compared with the backstepping control without disturbance compensation, the simulation results show that the proposed control strategy can effectively eliminate the adverse effects, enhance the robustness of the servo system and improve the position tracking accuracy of the motor.