串级不稳定时滞过程的内模控制器设计

针对串级不稳定时滞过程研究了内模控制器的设计方法。该方法副回路采用传统内模控制,能及时快速消除内环干扰对系统整体控制性能的影响;主回路采用一种二自由度内模控制结构,将设定值跟随特性与干扰抑制特性解耦,控制器的参数整定不需要在两种特性之间折中选择,克服了传统内模控制的不足。理论分析和仿真结果表明,该方法不仅能有效减少控制器的个数,而且可使系统同时获得良好的设定值跟随特性、干扰抑制特性和鲁棒性。     

网络控制系统的自整定鲁棒数字PID控制

为了有效地抑制网络延时对网络控制系统性能的影响,提出了一种鲁棒数字比例-积分-微分(PID)控制器设计方法.该方法将分布式的网络延时归结为单一延时;在大时变鲁棒数字PID控制方法的基础上,结合二自由度的内模控制结构,实现了控制器参数的数字双PID分离设计.对基于控制局域网络(CAN)总线的典型工业过程进行了仿真实验.结果表明,与最小化模型方法设计的控制器比较,采用设计的PID控制器能补偿网络上的延时,更加有效地抑制负载干扰并提高了系统的动态特性.     

Analysis on Biological Stability and Influencing Factors of Northern Living District Water Distribution System

多柔性连杆机械臂的自抗扰控制

刘延芳^1,2, 刘宏¹,孟瑶³

（1. 哈尔滨工业大学 机器人技术与系统国家重点实验室,哈尔滨 150001;

2.哈尔滨工业大学 航天学院,哈尔滨 150001;

3.上海宇航系统工程研究所,上海 201109）

创新点说明

将自抗扰控制应用到多柔性连杆机械臂的运动控制上。

研究目的

主要解决多柔性连杆机械臂的运动控制问题,在转角运动控制的同时,抑制柔性臂杆的振动。

研究方法

首先基于时标分离,将系统分解为快时标系统和慢时标系统：快时标系统为内环,采用最优二次型控制器,实现臂杆振动的快速抑制;慢时标系统为外环,采用自抗扰控制,抑制系统外界干扰、未建模动态等内外扰动,实现转角位置的精确控制。

结 果

采用自抗扰控制器可以显著提高转角控制精度,并抑制臂杆的振动,其中自抗扰控制器中采用飞线性PD控制器时,优势更为明显。

结 论

自抗扰控制器在应用于多柔性连杆机械臂的运动控制中具有一定的优势,可以进行工程推广。

关键词：多柔性连杆机械臂;自抗扰控制;飞线性比例微分控制器;跟踪微分器;状态扩张观测器

     

Robust tracking control for micro machine tools with load uncertainties

The quality of the micro-mechanical machining outcome depends significantly on the tracking performance of the miniaturized linear motor drive precision stage. The tracking behavior of a direct drive design is prone to uncertainties such as model parameter variations and disturbances. Robust optimal tracking controller design for this kind of precision stages with mass and damping ratio uncertainties was researched. The mass and damping ratio uncertainties were modeled as the structured parametric uncertainty model. An identification method for obtaining the parametric uncertainties was developed by using unbiased least square technique. The instantaneous frequency bandwidth of the external disturbance signals was analyzed by using short time Fourier transform technique. A two loop tracking control strategy that combines the μ-synthesis and the disturbance observer (DOB) techniques was proposed. The μ-synthesis technique was used to design robust optimal controllers based on structured uncertainty models. By complementing the μ controller, the DOB was applied to further improving the disturbance rejection performance. To evaluate the positioning performance of the proposed control strategy, the comparative experiments were conducted on a prototype micro milling machine among four control schemes: the proposed two-loop tracking control, the single loop μ control, the PID control and the PID with DOB control. The disturbance rejection performances, the root mean square (RMS) tracking errors and the performance robustness of different control schemes were studied. The results reveal that the proposed control scheme has the best positioning performance. It reduces the maximal errors caused by disturbance forces such as friction force by 60% and the RMS errors by 63.4% compared with the PID control. Compared to PID with DOB control, it reduces the RMS errors by 29.6%.     

基于反向解耦的PWM整流器分数阶内模控制

针对三相电压型PWM整流器提出一种新型的双闭环控制策略。基于同步旋转坐标系下PWM整流器的数学模型,利用反向解耦方法实现电流环的完全解耦,且避免了复杂的矩阵求逆运算;根据内模控制(internal model control, IMC)原理,设计了电流环IMC-PI控制器,该控制器仅有一个可调参数;在电压外环控制器的设计中,将IMC与分数阶控制(fractional order control, FOC)相结合,给出一种分数阶内模控制器的设计方法,并利用系统截止频率和最大灵敏度指标,实现了控制器参数的鲁棒整定。仿真结果表明,所提方法可使系统具有更好的动态响应及抗扰性能。     

Path tracking for vehicle parallel parking based on ADRC controller

A novel path tracking controller for parallel parking based on active disturbance rejection control (ADRC) was presented in this paper. A second order ADRC controller was used to solve the path tracking robustness, which can estimate and compensate model uncertainty caused by steering kinematics and disturbances caused by parking speed and steering system delay. Collision-free path planning technology was adopted to generate the reference path. The simulation results validate that the performance of the proposed path tracking controller is better than the conventional PID controller. The actual vehicle tests show that the proposed path tracking controller is effective and robust to model uncertainty and disturbances.     

永磁直线同步电机自适应内模控制研究

为了解决永磁直线同步电机（PMLSM）运行过程中对系统参数摄动及负载扰动等不确定因素敏感的问题,结合内模控制和模型参考自适应控制各自的优点,设计了PMLSM自适应内模控制器（AIMC）.仿真结果表明,自适应内模控制器同常规PI控制器相比,具有更好的动态稳定性和跟踪性能,对外界干扰具有较强的鲁棒性.     

Multi-constrained model predictive control for autonomous ground vehicle trajectory tracking

A multi-constrained model predictive control (MPC) algorithm for trajectory tracking of an autonomous ground vehicle is proposed and tested in this paper. First, to simplify the computation, an active steering linear error model is applied in the MPC controller. Then, a control increment constraint and a relaxing factor are taken into account in the objective function to ensure the smoothness of the trajectory, using a softening constraints technique. In addition, the controller can obtain optimal control sequences which satisfy both the actual kinematic constraints and the actuator constraints. The circular trajectory tracking performance of the proposed method is compared with that of another MPC controller. To verify the trajectory tracking capabilities of the designed controller at different desired speed, the simulation experiments are carried out at the speed of 3m/s, 5m/s and 10m/s. The results demonstrate the MPC controller has a good speed adaptability.     

多变量解耦双自由度PID控制系统设计

为了解决多变量时滞过程解耦器结构复杂且不能解析设计、控制器不易兼顾控制性能和鲁棒性的问题,提出一种新的解耦双自由度PID控制系统设计方法.针对时滞过程改进了Cai所提出的正则化解耦方法:从能量功率谱的角度重新解释并构造结构简单的解耦矩阵;将系统解耦成单回路后,采用双自由度PID结构设计各回路控制器.典型工业过程实例验证了设计的简单性和性能的有效性.采用该方法,解耦传递函数矩阵可以解析求解,双自由度PID控制器能够有效改善各回路高频段的解耦性能,获得良好的设定值跟踪性能和扰动抑制能力,并且可以方便地应用于控制现场.     

Design of Robust-Adaptive Controller of Extended Range Guided Munition

Finite state machine theory (FSM) is introduced and applied to global control of electric vehicle. Theoretical adaptation for application of FSM in control of electric vehicle is analyzed. Global control logic for parts of electric vehicle is analyzed and built based on FSM. Using Matlab/Simulink, BJD6100-HEV global control algorithm is modeled and prove validity by simulation.     

具干扰抑制的线性鲁棒迭代学习控制

针对不确定线性定常系统,考虑频域迭代学习控制器设计及干扰抑制问题.根据提出的闭环迭代学习控制律,推导出跟踪误差收敛的充分条件,并证明了它等价于系统没有采用迭代学习控制时的鲁棒性能条件,但在性能上却得到大大的改善.在完全跟踪不可能实现的情况下,讨论性能权重函数的选取,保证了跟踪误差收敛于实际工程容许的范围内,且参数选择非常简单.基于此性能权重函数,结合鲁棒控制理论,求解满足收敛条件的控制器.给出的仿真结果表明该设计方法的有效性.     

具有未知死区的SISO非仿射非线性系统间接自适应模糊控制

为了解决含有未知死区输入特性的SISO非仿射非线性系统的跟踪控制问题,提出了基于模糊自适应方法的控制器设计方案,把未知死区分解为一个线性项和一个扰动类似项,当系统状态可测时,利用模糊逻辑系统设计间接自适应模糊控制器,并结合跟踪误差信息设计自适应律;系统状态不可测时,通过引入误差观测器估计的状态变量,设计了间接自适应模糊输出反馈控制器．理论论证过程说明两种控制器能使系统的跟踪误差最终收敛到零的某一邻域,且闭环系统所有信号均有界. 仿真实验结果表明利用所设计控制方案可以使系统完成跟踪控制任务．     

IMC based robust PID controller tuning for disturbance rejection

It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejection. For the modified IMC-PID tuning rule, a method has been developed to obtain the IMC-PID setting in closed-loop mode without acquiring detailed information of the process. The proposed method is based on the closed-loop step set point experiment using a proportional only controller with gain K_(c0). It is the direct approach to find the PID controller setting similar to classical Ziegler-Nichols closed-loop method. Based on simulations of a wide range of first-order with delay processes, a simple correlation has been derived to obtain the modified IMC-PID controller settings from closed-loop experiment. In this method, controller gain is a function of the overshoot obtained in the closed loop set point experiment. The integral and derivative time is mainly a function of the time to reach the first peak(overshoot). Simulation has been conducted for the broad class of processes and the controllers were tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison. The PID controller settings obtained in the proposed tuning method show better performance and robustness with other two-step tuning methods for the broad class of processes. It has also been applied to temperature control loop in distillation column model. The result has been compared to the open loop tuning method where it gives robust and fast response.     

基于模糊单神经元控制的磁力轴承控制研究

针对磁力轴承的本质不稳定性和非线性,结合模糊控制和单神经元PID控制各自的特点,提出了一种模糊与单神经元控制相结合的控制方法.当系统偏差较大时,模糊控制器起主要的调节作用,同时加上适量的单神经元控制;当系统偏差较小时,单神经元控制和模糊控制同时起作用.该控制器克服了模糊控制存在稳态偏差和单神经元控制动态性能差的缺陷.仿真表明,使用该控制器可以实现磁悬浮转子的快速起浮,且超调量小、抗干扰能力强.     

Design of active disturbance rejection internal model control strategy for SISO system with time delay process

A novel control scheme of active disturbance rejection internal model control(ADRIMC) is proposed to improve the anti-interference ability and robustness for the dead-time process. The active anti-interference concept is introduced into the internal model control(IMC) by analyzing the relationship between IMC and disturbance observer control(DOB). Further, a design process of disturbance filter is presented to realize the active anti-interference ability for ADRIMC scheme. The disturbance filter is used to estimate an equivalent disturbance consisting of both external disturbances and internal disturbances caused by model mismatches.Simulation results demonstrate that the proposed method possesses a good disturbance rejection performance, though losing some partial dynamic performance. In other words, the proposed method shows a tradeoff between the dynamic performance and the system robust.     

高速无人驾驶车辆轨迹跟踪和稳定性控制

针对高速无人驾驶车辆运动控制过程中轨迹跟踪精度和稳定性难以同时保障的问题,提出综合前馈-反馈及自抗扰控制(ADRC)补偿相结合的横向控制算法. 通过车速和道路曲率信息计算前馈稳态前轮转向角,将质心侧偏角引入航向偏差,以车辆航向角偏差和侧向偏差作为参考量进行反馈控制,通过前馈-反馈控制提升瞬态轨迹跟踪性能. 设计自抗扰控制器,通过扩张状态观测器对未建模动态和内外界干扰进行估计,通过将后轮侧偏角控制在参考值附近来补偿前轮转角,提升无人驾驶车辆的转向稳定性和控制器的鲁棒性. 不同工况下的仿真结果表明,利用该方法可以保证高速无人驾驶车辆稳定地跟踪期望路径行驶,轨迹跟踪偏差较小,对车辆参数变化和外界干扰具有较强的鲁棒性.     

基于自抗扰控制技术的船舶直线航迹控制器设计

船舶直线航迹控制系统是一种单输入双输出系统,具有强非线性和典型的欠驱动特性;船舶运动又易受风、浪、流等干扰,使得航迹控制器的设计非常困难。本文给出了船舶直线航迹控制系统数学模型并对自抗扰控制技术(active disturbance rejection control technique, ADRC)进行了简要介绍。在原自抗扰算法的基础上,通过增加一个跟踪微分器以及控制律由两个被控量的误差组合而成的方法,突破了原有的自抗扰控制算法只适用于单输入单输出系统的限制,实现了船舶航向和横偏位移的良好控制。仿真结果证实了这种方法的有效性,不仅可以获得很好的系统动态性能和稳态性能,而且具有很强的鲁棒性。     

多缸电液调平系统相邻交叉耦合同步控制

针对某导管架平台电液调平系统多缸运动同步控制问题,引入最小相关轴数控制思想,基于相邻交叉耦合控制和滑模变结构控制理论,设计了多缸运动同步控制器,该同步控制器由1个单通道跟踪误差控制器和2个相邻同步误差控制器构成.对单通道子系统中由于长管路存在导致的时延问题,提出了一种具有滑模预估结构的误差跟踪控制器,并以四缸运动同步控制系统为例进行了仿真研究,结果表明该同步控制方法具有较好的控制效果和较强的鲁棒性,证明了方法的有效性.     

一种多变量解耦控制方法

本文提出了一种基于内模控制的多变量解耦控制方法,该方法同时还具有抗干扰及跟踪设定值的能力。     

基于线性自抗扰的DC/DC升压变换器的控制策略研究

为了改善DC/DC升压变换器的动态性能和抗干扰能力,提出了一种基于线性自抗扰控制(LADRC)的双环DC/DC变换器控制策略.首先,基于状态空间平均法推导出DC/DC升压变换器电压外环和电流内环的传递函数;其次,通过设计线性扩展状态观测器(LESO)和线性状态误差反馈控制律(LSEF)来实时估计和补偿外部的干扰和内部的不确定性;最后,利用仿真实验验证了该控制器的可行性.实验结果显示,该控制器比传统双环PI控制器具有更佳的鲁棒性和自适应性,因此该控制器可用于稳定变压器的直流母线输出电压.