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1.
永磁同步电机位置伺服系统的有限时间控制 总被引：1，自引：0，他引：1
针对永磁同步电机位置伺服系统控制问题,对有限时间控制技术的应用进行了研究.依据有限时间控制理论,利用反步构造法,对系统的位置环提出了一种基于反馈线性化和有限时间控制技术的策略.对干扰情况下闭环系统的性能进行了严格的数学分析.仿真结果表明:与传统的基于PD和反馈线性化的控制方案相比,基于有限时间控制技术的控制方案不仅使得闭环系统的位置跟踪误差具有更快的收敛速度,而且通过调节控制器参数可以使稳态误差的边界更小,系统具有更强的抗干扰能力.仿真结果验证了该方法的有效性. 相似文献
2.
考虑了一类含有时滞非线性系统鲁棒自适应控制问题.运用backstepping方法,巧妙构造了状态反馈控制器和自适应控制律.通过选取适当的Lyapunov函数,解决了系统中的时滞项.基于Lyapunov稳定性理论,所设计的控制器实现了闭环系统的渐近稳定.最后,给出了数值例子,并对系统进行了仿真,结果验证了方法的有效性. 相似文献
3.
Robust dynamic surface control (RDSC) is effective in alleviating the implementation difficulty of backstepping‐based multiple‐surface sliding control (MSSC) for a class of strict‐feedback nonlinear systems with mismatched uncertainties. However, the synthesis and analysis of the classical RDSC are conservative, which not only may lead to an impractical control law but also cannot fully reveal the technical nature of RDSC. This article provides a comprehensive study of a preferred RDSC law with an approximation of the signum function based on the singular perturbation theory. By formulating the control problem into a singular perturbation form, it is proven that the preferred RDSC recovers the performance of MSSC as the decrease of a filter parameter. The attractive features of the preferred RDSC revealed during the proposed synthesis and analysis include: (a) the control gain can be significantly reduced resulting in a sharp decrease of control energy and (b) the closed‐loop stability can be guaranteed by only decreasing the filter parameter. Simulation results have been shown to be consistent with the theoretical findings. 相似文献
4.
A mode decoupling control strategy is proposed for the active Kinetic Dynamic Suspension Systems (KDSS) with electrohydrostatic actuator (EHA) to improve the roll and warp mode performances. A matrix transfer method is employed to derive the modes of body and wheel station motions for full vehicle with active KDSS. The additional mode stiffness produced by the active KDSS is obtained and quantitatively described with the typical physical parameters. A new hierarchical feedback control strategy is proposed for the active KDSS to improve the roll and warp motion performances and simultaneously accounting for nonlinear dynamics of the actuators with hydraulic uncertainties. H∞ static output‐feedback control is employed to obtain the desirable mode forces, and a new projection‐based adaptive backstepping sliding mode tracking controller is designed for EHA to deal with address the nonlinearity and parameters uncertainty. This controller is used to realize the desirable pressure difference of EHA required from the target mode forces. Numerical simulations are presented to compare the roll and warp performances between the active KDSS, conventional spring‐damper suspension, and suspension with antiroll bar under typical excitation conditions. The evaluation indices are normalized and compared with radar chart. The obtained results illustrate that the proposed active KDSS with proposed controller does not produce additional warp motion for vehicle body, and has achieved more reasonable tire force distribution among wheel stations, the roll stability, road holding, and significantly improved ride comfort simultaneously. 相似文献
5.
This paper presents a control design for the one‐phase Stefan problem under actuator delay via a backstepping method. The Stefan problem represents a liquid‐solid phase change phenomenon which describes the time evolution of a material's temperature profile and the interface position. The actuator delay is modeled by a first‐order hyperbolic partial differential equation (PDE), resulting in a cascaded transport‐diffusion PDE system defined on a time‐varying spatial domain described by an ordinary differential equation (ODE). Two nonlinear backstepping transformations are utilized for the control design. The setpoint restriction is given to guarantee a physical constraint on the proposed controller for the melting process. This constraint ensures the exponential convergence of the moving interface to a setpoint and the exponential stability of the temperature equilibrium profile and the delayed controller in the norm. Furthermore, robustness analysis with respect to the delay mismatch between the plant and the controller is studied, which provides analogous results to the exact compensation by restricting the control gain. 相似文献
6.
In this paper, we investigate the trajectory tracking problems of the link angle and angle speed of the flexible joint manipulator model based on external disturbance, the control input and rate constraints. The controller of the flexible joint manipulator model is designed using the backstepping control scheme. To achieve this objective, the smooth hyperbolic tangent function is used to solve the problems of control input and rate constraints, and the stability is proved using Lyapunov function in the design procedure of the backstepping control scheme. Finally, the effectiveness of the proposed backstepping controller is verified by numerical simulation. 相似文献
7.
Jesús Linares‐Flores Arturo Hernndez‐Mndez Jacob Javier Vsquez‐Sanjuan Jos Fermi Guerrero‐Castellanos Gonzalo Curiel‐Olivares 《Advanced Control for Applications》2020,2(3)
This article deals with the low‐speed sensorless trajectory tracking control of a permanent magnet synchronous motor (PMSM). The rotor position and angular speed are obtained through back electromotive forces (back‐EMF), using extended state observers (ESOs) in the alpha‐beta coordinates. Additionally, the estimation of the back‐EMF is used by an algebraic module to reconstruct online the position and speed using an off‐line estimation of the back‐EMF parameter . The control law is derived using a robust recursive controller design methodology, namely; the backstepping design approach in the d‐q coordinates. Estimation schemes allow the adaptation of the angular position, angular speed, and the load torque parameters in the control law. With this adaptation, the controller achieves the necessary robustness to reduce the effects of endogenous and exogenous perturbations present in the PMSM system. The trajectory tracking task is achieved at low angular speed, with the presence of a load torque applied to the motor shaft. Experimental results at low‐speed and rated load/no‐load conditions are presented to demonstrate the effectiveness and robustness of the proposed scheme. 相似文献
8.
For a distributed parameter system with an input delay in the boundary, a feedback control law is presented by means of the backstepping method. The square integrability of input signal is verified based on the target system. Then, the boundedness and invertibility of the corresponding backstepping transformation are proved under the regularity of system and the admissibility of feedback operator. Thus, the resulting closed-loop system is shown to be exponentially stable. Finally, as an application, a numerical simulation of a one-dimensional Schrödinger equation with a delay input is carried out, and the simulation results demonstrate the effectiveness of the suggested control law. 相似文献
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