含有未知扰动的阀控电液回转系统MFA-SM控制

MFA-SM control for valve-controlled electro-hydraulic rotation system with unknown disturbances

针对阀控电液回转系统在围岩钻进过程中,由于参数不确定、未知负载以及外部扰动等非线性因素影响难以精确控制输出轴转速的问题,设计了基于RBFNN扰动观测器的MFA-SM控制方案。首先,通过改进的动态线性化方法将电液系统等价线性化为仅与系统I/O数据相关的增量模型,而未知负载及外部扰动则被合并为一个未知非线性时变项;然后,设计了RBFNN扰动观测器对该非线性项进行在线实时估计,并根据系统的I/O数据来估计系统时变伪梯度参数;最后,给出了相应的控制器设计。仿真实验结果表明,所设计的MFA-SM控制器能够对未知负载及外部干扰进行有效补偿,相较于其他方法,该方案使得系统调节时间缩短了约10~15 s,最大超调量降低了7.4%左右,且转速跟踪误差能够收敛到0。

A MFA-SM control scheme based on RBFNN disturbance observer is designed to solve the problem that it is difficult to accurately control the output shaft speed of the valve-controlled electro-hydraulic rotation system during the drilling of surrounding rock due to the non-linear factors such as uncertain parameters, unknown load and external disturbance. First, an improved dynamic linearization method is used to linearize the electro-hydraulic system to an incremental model only related to the system I/O data. Unknown loads and external disturbances are combined into an unknown nonlinear time-varying term. Then, an RBFNN disturbance observer is designed to estimate the nonlinear term on-line in real time, and the time-varying pseudo-gradient parameters are estimated from the system I/O data. Finally, the corresponding controller design is given. The simulation results show that the MFA-SM controller can effectively compensate unknown load and external disturbance. Compared with other methods, this scheme shortens the system adjustment time by 10 to 15 s, reduces the maximum overshoot by about 7.4%, and the speed tracking error can converge to 0.