A Design Of Multiloop Predictive Self‐Tuning Pid Controllers

In this paper, a new design scheme of multiloop predictive self‐tuning PID controllers is proposed for multivariable systems. The proposed scheme firstly uses a static pre‐compensator as an approximately decoupling device, in order to roughly reduced the interaction terms of the controlled object. The static matrix pre‐compensator is adjusted by an on‐line estimator. Furthermore, by regarding the approximately decoupled system as a series of single‐input single‐output subsystems, a single‐input single‐output PID controller is designed for each subsystem. The PID parameters are calculated on‐line based on the relationship between the PID control and the generalized predictive control laws. The proposed scheme is numerically evaluated on a simulation example.     

应用于直流电机调速系统的变参数PI控制器

针对传统双模控制用于速度控制系统时存在的问题，提出了一种变参数PI控制器。该控制器对传统双模控制的切换条件进行了修正，无论在快速跟踪阶跃给定，还是有效抗负载扰动，均有更为优良的动态性能。     

直流调速系统的新型二自由度控制器

针对直流调速系统提出了一种新的二自由度内模控制器设计方法,所设计的控制器结构简单,容易实现,而且参数调整方便,它可以使系统同时具有良好的跟随性能和抗扰性能,仿真研究结果表明了它的有效性。     

Self‐triggered model predictive control for networked control systems based on first‐order hold

In this work, a new self‐triggered model predictive control (STMPC) algorithm is proposed for continuous‐time networked control systems. Compared with existing STMPC algorithms, the proposed STMPC is implemented based on linear interpolation (first‐order hold) rather than the standard zero‐order hold, which helps further reduce the difference between the self‐triggered control signal and the original time‐triggered counterpart and thus reduce the rate of triggering. Based on the first‐order hold implementation, a self‐triggering condition is derived and the corresponding theoretical properties of the closed‐loop system are analyzed. Finally, the comparison between the proposed algorithm and the zero‐order hold–based STMPC is carried out through both theoretical analysis and a simulation example to illustrate the effectiveness of the proposed method.     

基于模糊PI控制的永磁同步伺服电机转速系统仿真分析

由于外部环境的日益复杂、被控对象要求的不断变化,使用传统的PI控制已不能满足控制系统的性能要求,为了提高永磁同步伺服电机转速控制系统的性能,本文设计了一种将模糊控制与经典PI控制结合的模糊PI控制系统.运用Matlab分别对经典PI控制和模糊PI控制系统在永磁同步伺服电机转速控制的仿真分析,对比仿真实验结果表明：模糊PI控制器上升时间明显缩短,响应速度明显加快,超调量更小,抗干扰能力强.     

水轮机调节系统的状态PI控制器研究

虽然状态PI控制器已经提出很多年,但至今未在水轮机转速控制中有所应用。本文应用状态PI控制,从水轮机控制系统状态反馈模型出发,设计水轮机调节系统状态PI控制器,并对状态PI最优控制与传统推荐PID最佳调节进行比较分析。仿真结果表明:两者动态过程明显不同,前者的动态过程呈现非周期快速稳定特点,而后者的动态过程则为衰减振荡过程,并且状态PI控制在负荷变化时有更好的控制品质。     

Development of a Novel Self‐Tuned Adaptive Supervisory Cerebellar Model Articulation Controller for Induction Motor Drive

This work presents a novel speed control scheme for an induction motor (IM) using an adaptive supervisory differential cerebellar model articulation controller (ASDCMAC). The ASDCMAC has a supervisory controller and an adaptive differential cerebellar model articulation controller (ADCMAC), and the ASDCMAC is utilized as the speed controller. The supervisory controller monitors the control process to keep speed tracking error within a predefined range, and the ADCMAC learns and approximates system dynamics. The connective weights of ADCMAC are adjusted online, according to adaptive rules derived in Lyapunov stability theory, to ensure system stability. The robustness of the proposed ASDCMAC against parameter variations and external load torque disturbances is verified via simulations and experiments, respectively. Three control schemes, the ASDCMAC, fuzzy control, and PI control, are investigated experimentally, and a performance index, root mean square error (RMSE), is utilized for each scheme. The experimental results demonstrate that the ASDCMAC outperforms the two other control schemes with external load torque variations.     

基于二自由度PI的微型涡喷发动机转速闭环控制

针对传统PI控制无法使微型涡喷发动机的扰动抑制性能与设定值跟踪性能同时最佳的问题,开展了微型涡喷发动机二自由度（Two-Degree-of-Freedom,2-DOF）PI控制研究。首先基于Speedgoat实时目标机搭建了快速原型试验系统。根据发动机开环试验数据辨识得到不同稳态点下的传递函数模型,在此基础上设计了2-DOF PI控制器,并进行仿真验证。最后将控制算法部署至Speedgoat中开展实物试验。结果表明,设计的2-DOF PI控制器能够使微型涡喷发动机的扰动抑制性能与设定值跟踪性能同时最佳,并在发动机较大的工作范围内有良好的控制性能。     

Design of UDE‐based controllers from their two‐degree‐of‐freedom nature

The control algorithm based on the uncertainty and disturbance estimator (UDE) is a robust control strategy and has received wide attention in recent years. In this paper, the two‐degree‐of‐freedom nature of UDE‐based controllers is revealed. The set‐point tracking response is determined by the reference model, whereas the disturbance response and robustness are determined by the error feedback gain and the filter introduced to estimate the uncertainty and disturbances. It is also revealed that the error dynamics of the system is determined by two filters, of which one is determined by the error feedback gain and the other is determined by the filter introduced to estimate the uncertainty and disturbances. The design of these two filters are decoupled in the frequency domain. Moreover, after introducing the UDE‐based control, the Laplace transform can be applied to some time‐varying systems for analysis and design because all the time‐varying parts are lumped into a signal. It has been shown that, in addition to the known advantages over the time‐delay control, the UDE‐based control also brings better performance than the time‐delay control under the same conditions. Design examples and simulation results are given to demonstrate the findings. Copyright © 2010 John Wiley & Sons, Ltd.     

A comparison study of different control strategies for grid‐connected three phase two‐level power converters

This paper presents a comparison study of different control schemes for grid‐connected three phase two‐level power converters. All control strategies adopt the double‐loop control structure which consists of voltage regulation loop and instantaneous power tracking loop. In the external loop, voltage regulation loop, PI, fuzzy PI, adaptive controllers and PI controller plus extended state observer (ESO) are utilized to regulate the output voltage. The merits, drawbacks and design procedures of four methods are compared, investigated and analyzed. The second order sliding mode (SOSM) controllers are applied into the internal loop, instantaneous power tracking loop, to drive the active power and reactive power tracking their set points. The performance differences of these control strategies are compared through the real simulation.     

Development Of Cvt Control System And Its Use For Fuel‐Efficient Operation Of Engine

Continuously variable transmission (CVT) provides an automobile with the ability to change the gear ratio continuously, which can then improve not only ride quality such as acceleration performance but also fuel‐efficiency. However, to take advantage of the ability, a control system that can precisely control the gear ratio is required. This paper proposes such a control system for a belt‐driven CVT system. For controller design, first the CVT system is modeled by analytical and experimental approaches. The resultant static and dynamic characteristics provide a nonlinear first‐order model with an uncertain time constant and time delay. The nonlinear steady‐state gain is adjusted to one by a gain‐scheduled pre‐compensator. Thereby the plant model becomes a linear first‐order lag system with a dead time. The next step is controller design using the plant model. To guarantee stability and control performance against the parameter variation and time delay, the μ‐synthesis, a robust control method, is employed for feedback control. In addition, a feedforward controller is incorporated into the feedback control system to obtain better output response. The feedforward controller is given by a combination of the inverse system of the plant and a reference model that gives desired output response. As a result, the control system becomes a two‐degree‐of‐freedom control system. To evaluate the performance of the control system and its effectiveness on the fuel‐efficiency, computer simulation and driving tests were conducted. The simulation and experiment results prove that the proposed control system can make the gear ratio track a reference output quickly and precisely in the presence of the uncertainties. The results also show that the control system improves fuel‐efficiency by changing the gear ratio so that the engine torque and its revolution speed can satisfy optimum‐efficiency operating condition.     

Self‐tuning minimum variance control of linear systems followed by saturation nonlinearities in a noisy frame

The aim of the present paper was to increase the efficiency of self‐tuning minimum variance (MV) control of linear systems followed by the so‐called hard nonlinearities. To this end, an approach based on reordering of observations to be processed for the reconstruction of an unmeasurable internal intermediate signal, which acts between a linear dynamic time‐invariant (LTI) system and a static nonlinear block of the closed loop Wiener system with a saturation nonlinearity in an output, has been developed. The technique based on the ordinary least squares and on data partition is used for the internal signal extraction. The results of numerical simulation, identification, and self‐tuning MV control as well as generalized MV control of the second‐order discrete‐time closed loop LTI system with the saturation nonlinearity are given by the computer. Copyright © 2012 John Wiley & Sons, Ltd.     

基于模糊控制的IPMSM速度控制器及电流控制器设计

本文在IPMSM矢量控制的基础上,利用模糊控制实现对IPMSM系统的自适应控制,运用FLC分析和设计了速度和电流控制器,给出了模糊规则和隶属函数。仿真结果表明,与采用传统的PID控制相比,采用模糊控制可以很好地克服系统的非线性、时变、强耦合等因素的不良影响,使系统具有较好的动态特性和鲁棒性,提高了系统的性能。     

Distributed Control for Coupled Nonholonomic Mobile Robots under the Event‐Triggered and Self‐Triggered Frameworks

In this paper, a coordinated tracking problem for coupled nonholonomic mobile robots is considered. An event‐triggered control strategy is first proposed to guarantee that the robots can form a prespecified geometric pattern while the centroid of the geometric pattern can track a reference signal. The results are then extended to the self‐triggered case, where continuous monitoring of the agent states is not needed. The stability of the system is proved with the aid of the Lyapunov techniques. Finally, numerical examples are presented to verify the validity of the theoretical results.     

多变量分数阶滞后系统预测控制参数解析调优

提出了一种针对各子系统由一阶加分数阶滞后模型描述的多变量系统模型预测控制参数解析调优方法.首先推导了多变量分数阶滞后系统的状态空间模型;其次,基于该模型构建模型预测控制优化问题,并获得了控制信号的解析表达式;再次,对闭环控制系统进行解耦分析,揭示了模型预测控制器参数与系统闭环性能间的定量关系,通过将参数调优问题转化为极点配置问题,得到能够保证闭环系统性能的模型预测控制器参数取值的解析表达式;最后通过仿真实验验证了本文所设计的参数解析调优算法的有效性.     

Modeling and Control Approach to Coupled Tanks Liquid Level System Based on Function‐Type Weight RBF‐ARX Model

A multi‐input multi‐output (MIMO) FWRBF‐ARX model, which adopts radial basis function (RBF) neural networks with function‐type weights (FWRBF) to approximate the coefficients of the state‐dependent AutoRegressive model with eXogenous input variables (SD‐ARX), is utilized for describing the dynamics of a coupled tanks liquid system. Based on local linearization information of the MIMO FWRBF‐ARX model, a predictive control strategy is proposed. In the algorithm, the control actions of the model predictive control (MPC) are calculated based on the local linearization of the MIMO FWRBF‐ARX model at current working point. Real‐time control experiments are carried out on the coupled tanks liquid system. The detailed comparative experiments demonstrate the feasibility and effectiveness of the proposed modeling and model‐based control strategy for the coupled tanks plant.     

Eso‐Based Adaptive Robust Control of Dual Motor Driving Servo System

Based on extended state observer (ESO), we propose an adaptive robust control (ARC) for a dual motor driving servo system, in which there exist nonlinearities affecting control performance. To apply ESO and estimate the lumped uncertainty online, backlash and friction are analyzed and the nonlinear model of the plant is derived. We achieve several control objectives. First, the bias torque is considered in order to eliminate the effect of backlash. Second, the speed feedback is used to maintain the speed synchronization of motors. Then, to achieve feedforward control, finite‐time ESO is designed to estimate the unknown nonlinearities online. Furthermore, the ESO‐based adaptive robust controller is designed to guarantee L_∞ of tracking error by an initialization method, maintaining the transient performance of tracking behavior. Finally, extensive experimental results on a practical test rig validate the effectiveness of our proposed method.     

Composite Disturbance‐Observer‐Based Control and Control for High Speed Trains with Actuator Faults

To guarantee the position and velocity tracking performance of high speed trains (HSTs) with actuator faults, a composite control algorithm consisting of the disturbance‐observer‐based control (DOBC) and control is proposed. Based on the multiple point‐mass model, the dynamics of HSTs is established by a cascade of carriages which are connected by flexible couplers, during the procedure of which, the running resistance, actuator faults and multiple disturbances are taken into account. The multiple disturbances are composed of two parts, one of which is the ramp resistance due to the track slope, the other is unknown gusts which can be modeled as a harmonic disturbance with time‐varying frequency. The unknown gusts is estimated and rejected via the DOBC methodology, meanwhile, the running resistance and the ramp resistance are attenuated by the control methodology. According to the Lyapunov stability analysis and LMI‐based algorithms, main results are derived such that the closed‐loop system is asymptotically stable and the desired performance can be guaranteed. Compared with the numeral simulation results with the single control method, it is demonstrated that the proposed control methodology is more effective and the system has a higher precision of position and velocity tracking.     

基于遗传算法的EHA调速系统设计与优化

电机调速系统是飞机电静液作动器(EHA)的关键部分,直接影响着机载作动系统的可靠性.EHA对调速系统鲁棒性,快速性有着较高的性能要求,传统的试凑法设计调速系统的调节器难以满足性能的要求.首先针对EHA的实际工作原理,建立了EHA调速控制的模型,用PID调节器设计双闭环负反馈控制系统,然后采用遗传算法对PID调节器参数寻优整定,最后根据实际工作情况与性能要求进行了仿真分析.仿真结果表明,利用遗传算法寻优设计PID调节器控制EHA所采用的大功率无刷直流电机,可以获得良好的稳定性、鲁棒性和动态性能.     

低速飞行模拟转台变结构控制设计

针对飞行模拟转台在低速运行时的控制问题进行研究。由于摩擦力矩对飞行模拟转台在低速运行的影响较大,为了使转台在低速运行时具有精确的跟踪能力,采用变结构控制方法设计了控制器,并利用干扰观测器对摩擦力矩进行估计,从而在不增加系统硬件设备及改变转台结构的情况下对摩擦力矩进行补偿。仿真表明,该方法可以使飞行模拟转台在低速情况下具有良好的跟踪能力,干扰观测器可以准确地对摩擦力矩进行估计,并有效地补偿了摩擦力矩的影响,验证了该方法的有效性。