多轴同步控制系统的寿命预测和延寿方法

Research on life prediction and extension method of multi-axis synchronous control system

随着多轴同步控制系统应用日益广泛,对其安全可靠性的要求也愈加迫切,尤其当元部件不可避免地逐渐退化时,对系统依旧具有持续工作的期许.鉴于此,针对一类考虑单轴执行器退化的多轴同步控制系统,将感知与认知相结合,提出一种基于系统剩余寿命(RUL)预测的动态矩阵(DMC)-PID串级延寿控制方法.首先,在不改变原有多轴同步系统结构的前提下,通过串级方式引入DMC作为延寿控制器,辅以PHM模块作为自主维护分析决策器,构建具有实时RUL预测和延寿功能的多轴同步系统新架构;然后,建立执行器隐含退化状态与多轴同步系统性能等感知信息之间的联系,得到多轴同步系统RUL分布的解析解并用于实时预测;接着,将其与同步系统的期望工作时长相结合,作为在线自主维护的认知依据,并基于给出的一种同时依赖执行器退化状态和延寿期许的自适应参数调节律,用以在线动态调整DMC约束矩阵Q和R的元素值,通过更契合退化过程特征和延寿需求的方式以减缓执行器退化、延长系统使用寿命,进而实现多轴系统性能与耐用性之间的更优折衷平衡;最后,通过舞台多电机同步控制系统仿真实验验证所提出方法的有效性.

With the increasing application of multi axis synchronous control systems,the requirements of safety and reliability are becoming more and more urgent.Even when the original components are gradually degraded,many systems still have the expectation of continuous working hours.Thus,a dynamic matrix-PID cascade life extension control(DMC)method based on system residual life(RUL)prediction is proposed.Firstly,without changing the structure of the original multi axis synchronization system,a new architecture with real-time life prediction and life extension function is constructed by introducing the DMC as the life extension controller and the PHM module as the independent maintenance analysis decision-maker.Secondly,by establishing the relationship between the perceptual information such as the implicit degradation state of the actuator and the performance of the multi axis synchronization system,the analytical solution of the RUL distribution of the multi axis synchronization system is obtained and used for real-time prediction.Then,it is combined with the expected working time of the synchronization system as the cognitive basis of on-line autonomous maintenance,and based on an adaptive parameter adjustment law which depends on both actuator degradation state and life extension period,then used to dynamically adjust the element values of DMC constraint matrices Q and R on-line.The degradation of the actuator is slowed down and the service life of system is prolonged by better matching the characteristics of the degradation process and the demand for life extension,so as to achieve a better compromise balance between the performance and durability of the multi axis system.Finally,the effectiveness of the proposed method is verified by the simulation experiment of the stage multi motor synchronous control system.