【作者】 张慧；

【导师】 缪仲翠；

【作者基本信息】 兰州交通大学 ， 控制科学与工程， 2025， 硕士

【摘要】 随着高精密加工技术的不断发展,作为加工机床驱动系统的核心部件,永磁同步直线电机的控制精度要求日益提高,同时对闭环控制系统中动子位置和速度信息的采集要更加精准。在实际应用中,通常采用光栅或磁栅等物理传感器来获取电机的速度与位置信息,但物理传感器的使用不仅增加了系统成本,还限制了电机的应用场景。因此,将无传感器动子速度及位置估计技术应用到永磁同步直线电机的闭环控制当中,对于实现高效、低成本的直接驱动控制系统而言有着重大意义。针对这一问题,本文的主要研究内容如下:首先实现了永磁同步直线电机模型预测电流控制,针对逆变器存在的非线性因素对模型预测电流控制造成的影响进行分析。为了降低电机电流畸变、减少对模型预测电流控制的影响,本文提出了一种基于拉格朗日插值的误差电压补偿方法。综合考虑多种非线性因素,通过拉格朗日插值公式获得误差电压与相电流之间的映射关系,并以表格形式存储。在系统运行时,通过实时查表操作确定误差电压,再利用电压前馈补偿的方式来抑制非线性误差,进而提升电机闭环控制性能。为验证所提策略对逆变器非线性因素抑制的有效性,分别对不同速度工况下补偿前后的永磁同步直线电机模型预测电流控制系统进行仿真。仿真结果表明,所提方案对逆变器非线性因素导致的电流波动有很好的抑制效果。其次,为实现永磁同步直线电机无位置传感器控制,本文设计了基于改进超扭曲滑模观测器无传感器控制方案。该方案引入超扭曲算法,将其与传统滑模观测器相结合,利用积分环节替代传统滑模观测器中的高频切换函数,以减少抖振的产生。同时,采用过渡更加平滑的双曲正切函数作为切换函数,进一步降低高频切换引起的抖振,且保持系统的快速响应能力。此外,设计补偿锁相环对基于超扭曲滑模观测器得到的反电动势进行处理,有效消除斜坡频率变化时的跟踪误差,从而显著提升电机动子位置与速度的估计精度。搭建仿真平台对所提策略的有效性进行验证,仿真结果表明在不同工况下,所提策略均能实现对电机速度及位置的有效估计。最后,为了提高系统的抗扰动能力设计了降阶扰动观测器。将永磁同步直线电机与传动机构及工作台组成的机械系统视为整体,建立其运动方程,基于该方程设计降阶扰动观测器。通过合理配置降阶扰动观测器的增益,实现对摩擦力扰动的有效观测及补偿。通过仿真实验可以发现,将降阶扰动观测器应用到永磁同步直线电机无位置传感器控制策略中,能够实现对系统摩擦力及负载扰动的实时观测和补偿,提高无位置传感器控制的精确性。综上所述,本文提出的基于扰动补偿的永磁同步直线电机无位置传感器控制策略在满足基本的对电机位置及速度观测要求的前提下,有效地降低了系统成本,提升了控制系统的稳定性、动态响应性以及鲁棒性,为低成本、高精度直线驱动系统提供了理论支撑与技术方案。更多还原

【Abstract】 With the continuous development of high-precision machining technology,as the core component of the machining machine tool drive system,the control accuracy requirements of the permanent magnet synchronous linear motor are increasing day by day.At the same time,the acquisition of the mover position and speed information in the closed-loop control system should be more accurate.In practical applications,physical sensors such as gratings or magnetic grids are usually used to obtain the speed and position information of the motor,but the use of physical sensors not only increases the system cost,but also limits the application scenarios of the motor.Therefore,the application of sensor-less kinematic velocity and position estimation techniques to the closed-loop control of permanent magnet synchronous linear motors is of great significance for the realization of an efficient and low-cost direct drive control system.In response to this problem,the main research contents of this thesis are as follows:Firstly,the model predictive current control of permanent magnet synchronous linear motor is realized.At the same time,the influence of the nonlinear factors of the inverter on the model predictive current control is analyzed.In order to reduce the distortion of the motor current,an error voltage compensation method based on Lagrange interpolation is proposed.Considering a variety of nonlinear factors,the mapping relationship between the error voltage and the phase current is obtained by the Lagrange interpolation formula and stored in the form of a table.When the system is running,the error voltage is determined by real-time look-up table operation,and then the nonlinear error is suppressed by voltage feedforward compensation,so as to improve the closed-loop control performance of the motor.In order to verify the effectiveness of the proposed strategy to suppress the nonlinear factors of the inverter,the model predictive current control system of the permanent magnet synchronous linear motor before and after compensation under different speed conditions is simulated respectively.The simulation results show that the proposed scheme has a good suppression effect on the current fluctuation caused by the nonlinear factors of the inverter.Secondly,in order to realize the position sensor-less control of permanent magnet synchronous linear motor,this thesis designs a sensor-less control scheme based on the improved super-twisted sliding mode observer..In this scheme,the super-twisting algorithm is introduced,which is combined with the sliding mode observer,and the integral link is used to replace the high-frequency switching function in the traditional sliding mode observer to reduce the chattering.At the same time,the hyperbolic tangent function with smoother transition is used as the switching function to further reduce the chattering caused by high-frequency switching and maintain the fast response ability of the system.In addition,a compensation phase-locked loop is designed to process the back electromotive force obtained based on the super-twisting sliding mode observer,which effectively eliminates the tracking error when the slope frequency changes,thereby significantly improving the estimation accuracy of the position and velocity of the motor mover.The simulation platform is built to verify the effectiveness of the proposed strategy.The simulation results show that the proposed strategy can effectively estimate the speed and position of the motor under different working conditions.Finally,a reduced-order disturbance observer is designed to improve the system’s disturbance resistance.The mechanical system composed of permanent magnet synchronous linear motor,transmission mechanism and worktable is regarded as a whole,its equation of motion is established,and the reduced-order disturbance observer is designed based on this equation.By reasonably configuring the gain of the reduced-order perturbation observer,the effective observation and compensation of friction perturbation is realized.Through simulation experiments,it can be found that the application of the reduced-order perturbation observer to the position sensor-less control strategy of permanent magnet synchronous linear motor can realize the real-time observation and compensation of system friction and load perturbation,and improve the accuracy of sensor-less control.In summary,the sensor-less control strategy of permanent magnet synchronous linear motor based on disturbance compensation proposed in this thesis effectively reduces the system cost,improves the stability,dynamic response and robustness of the control system under the premise of meeting the basic requirements of motor position and speed observation,and provides theoretical support and technical solutions for low-cost and high-precision linear drive systems.更多还原