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1.
针对磁轴承系统中存在不平衡振动和传统滑膜变结构控制存在抖振较大的问题,提出了一种模糊滑膜变结构控制方案,首先,建立了主动磁轴承系统在不平衡力干扰下的五自由度动力学模型,然后在滑膜变结构控制具有抖振较大这一缺点的基础上采用模糊控制器输出的绝对值作为离散滑膜控制器的增益,设计了一种二维模糊控制器来抑制抖振,通过用传统分散PID控制器和模糊滑膜变结构控制器两种方法对以不平衡力干扰下的五自由度磁轴承转子系统为对象进行仿真,仿真表明,模糊滑膜变结构控制方案能有效抑制不平衡振动且具有更快的调节速度、更小的超调量。系统性能得到了很大了改善,自适应较为理想。  相似文献   

2.
针对中央空调冷冻水系统的滞后、时变、非线性等特点,提出将PID控制和粒子群算法相结合,设计出基于改进粒子群优化算法的冷冻水系统变流量PID控制器,进行了两者对系统回水温度控制的仿真及对比分析,结果表明采用DSAPSO的PID自适应控制器后,系统能快速回到设定值,由此反映系统能较快消除干扰,该算法使系统具有较强鲁棒性和自适应能力,算法可以保证回水温度趋近于设定值12℃,即当空调房间的负荷发生变化时,冷冻水的回水温度基本能够稳定在设定的范围内。  相似文献   

3.
永磁同步电机是一个多变量、强耦合、非线性时变系统,在位置控制过程中易受外部负载扰动影响,为了提高伺服系统的鲁棒性,提出了一种基于扩张状态观测器的永磁同步电机位置滑模变结构反步控制方法。在永磁同步电机数学模型的基础上,提出了将反步控制与滑模变结构结合在一起的控制方法,提高了系统快速响应性以及对外界扰动的抑制能力;设计了扩张状态观测器(ESO)对外部负载扰动进行实时观测,及时对控制量进行调整,有效地减小滑模变结构中的趋近律参数。仿真结果表明,本文设计控制器能够实现高精度的给定位置跟踪控制,对于负载扰动具有强的抑制能力。  相似文献   

4.
为了提高永磁同步电机调速控制系统整体性能,设计了一种新型指数趋近律,在传统的指数趋近律上引入了终端吸引子和系统状态量的幂函数,从而抑制了滑模固有抖振现象,并提高了滑模趋近速度;在该新型指数趋近律的基础上设计了永磁同步电机滑模速度控制器,并与传统指数趋近律进行了仿真试验比较,仿真结果表明,该新型指数趋近律能有效提高电机转速响应速度,有效抑制了抖振现象,提高了系统的鲁棒性。  相似文献   

5.
本文主要研究了基于滑模变结构控制的采煤机滚筒调高系统设计。首先建立了采煤机调高系统的闭环传递函数,通过传递函数得到了该系统的状态空间方程,然后在该系统的控制器设计中引入了滑模变结构控制,最终得到了采煤机滚筒调高系统的滑移面切换函数。在此基础上对采煤机调高系统进行MATLAB模拟仿真,结果表明:当采煤机滚筒调高系统中引入滑模变结构控制器后极大改善了采煤机滚筒调高系统工作性能。  相似文献   

6.
趋近律控制方法能够提高滑模运动的动态品质,本文针对传统的指数趋近律存在一定缺陷,提出了一种基于时变切换增益的指数趋近律方法。设计了永磁同步电机电流滑模控制器,在切换增益中加入修正因子,使得切换增益在趋近运动以及接近滑模区时能够保持较小的值,且能够随着系统状态在滑模运动过程中收敛;在控制器模型中建立状态方程,并对滑模面、趋近律进行了设计,详细介绍了控制律推导过程。最后通过仿真实验验证了该方法的有效性。  相似文献   

7.
本文应用逆系统法对系统进行线性化解耦后,运用滑模变结构控制理论,设计了基于滑模变结构控制的STATCOM控制器。建立了MATLAB仿真模型,取得了良好的控制效果,并与PI控制进行了比较,结果证明此控制策略的优越性和可行性。  相似文献   

8.
针对二级倒立摆系统的快速响应及其稳定和鲁棒控制问题,以直线二级倒立摆为研究对象,在建立其非线性数学模型的基础上,利用极点配置方法设计了滑模变结构控制器。将所设计的控制器应用到二级倒立摆系统,实验仿真表明,该控制策略实现了对二级倒立摆系统的实时跟踪控制,系统具有较好稳定控制和较强抗干扰能力。  相似文献   

9.
《科技风》2017,(11)
针对参数不匹配的两个异结构混沌系统,基于微分方程稳定性理论,给出了一类不同构混沌系统的自适应同步策略.根据两个混沌系统的不同结构、参数互异的特征,选择适当的参数自适应律和自适应控制器,构建同步数学模型,实现了系统的混沌同步.并且通过Matlab软件数值仿真验证了所设控制器的有效性和方法的可操作性。  相似文献   

10.
本文针对变流量空调水系统的惯性大、时间滞后等特点以及传统PID控制方法调节效果不佳等问题,采用自适应调整惯性权重的粒子群(DSAPSO)算法,初步对变流量空调冷冻水系统的回水温度与水泵转速进行优化控制。采用DSAPSO的PID自适应控制器,经过Matlab仿真后,控制环节的上升时间、超调量及调整时间得到较大改善,系统控制品质得到了一定提高,系统表现出良好的动态性能及较强的鲁棒性。因此,可将DSAPSO进一步应用于整个空调水系统的控制环节,以完成空调水系统的优化控制。  相似文献   

11.
A novel variable structure controller is investigated for satellite attitude control. This novel controller does not lead to a sliding mode, which avoids the chattering problem, making it suitable for practical implementation. Detailed formulation of the controller is presented along with analytical stability analysis for a second order system. The system having this nonlinear controller is homogeneous, which leads to a similar response at large and small deviations from the equilibrium. A procedure for tuning homogeneous controllers for all initial conditions is proposed. A detailed model of the satellite attitude dynamics, actuator dynamics, and delays in the system is utilized to optimize controller gains numerically. A comparative analysis shows the superiority of the proposed controller over a conventional PID controller in terms of better transients and lower energy consumption.  相似文献   

12.
刘飞 《中国科技纵横》2011,(22):320-321
本文应用状态反馈线性化方法对电枢反应非线性进行线性化处理,通过适当的非线性状态变换和输入变换,将速度非线性控制系统综合问题转化为线性系统的综合问题,并采用对系统参数变化及外界扰动具有较强鲁棒性的滑模变结构控制方法,实现了直流电机速度的跟踪控制。  相似文献   

13.
The recent transition in power generation and consumption is based on the integration of renewable energy sources using DC microgrids. To facilitate this integration, a multi-source DC microgrid structure with wind, photovoltaics, fuel cell and hybrid energy storage system including battery and supercapacitor is presented in this paper. These sources are linked to a DC-bus via DC-DC converters. A hierarchical control strategy with a device and a system-level control for coordinated control between energy sources and their storage devices is proposed. In the device-level control, a variable structure based sliding mode control is applied to regulate the DC bus voltage and to ensure global asymptotic stability. Whereas, the system-level control compensates for the supply and demand mismatches by using a rule-based fuzzy system. To verify the effectiveness of the proposed scheme and the superiority of one controller over another, the proposed controllers are simulated and compared in the MATLAB/Simulink environment under varying load and weather data conditions. Results show that super twisting sliding mode control had negligible chattering as well as better convergence as compared to controllers. Furthermore, the efficiency of the developed scheme is validated by controller hardware in loop experiments.  相似文献   

14.
The requirement for An electrical grid-connected wind turbine is that the synchronous generator speed is stable within a required speed range for the electrical grid. In this paper, a hydraulic wind turbine (HWT) system is considered, and the working principle and working conditions of the HWT are introduced. A novel speed control method is proposed in this paper, using both a proportional flow control valve and a variable displacement motor, which are adjusted in combination to control the speed of the HWT. By establishing a state space model of the HWT and solving the nonlinear system with a feedback linearization method, a bivariate tracking controller is constructed to realize accurate speed control under fluctuating wind speed and the load disturbance conditions. The effectiveness of the control method is verified by simulation, but experimental results highlight problems with the method. The theoretical controller is simplified to reduce sensitivity to measurement noise and modeling error. The control effect has been improved to some extent, but it is limited. Based on these results, combined with the sliding mode variable structure control method and the feedback linearization method to solve the problem of measurement noise and modeling error, and the effectiveness of the control law is finally verified experimentally. It lays a theoretical foundation for the practical application of HWT.  相似文献   

15.
通过对高速公路在运行中遇到的主要问题的阐述,分析了可变限速控制在高速监控系统中的作用。针对高速公路可变限速控制是一个非线性时变系统,难于用数学模型进行建摸这一特点,提出了BP神经网络控制方法。阐述了BP神经网络的学习算法,根据高速公路主线上车辆数目以及路面状况、气象条件等信息,设计了高速公路可变速度标志神经网络控制器,并对控制器进行了仿真研究。仿真表明:网络学习速度快,自适应强,泛化能力好,结果精度高,对交通流限速控制中具有一定的推广应用价值。  相似文献   

16.
Auto-structuring fuzzy neural system for intelligent control   总被引:1,自引:0,他引:1  
An auto-structuring fuzzy neural network-based control system (ASFNS), which includes the auto-structuring fuzzy neural network (ASFNN) controller and the supervisory controller, is proposed in this paper. The ASFNN is used as the main controller to approximate the ideal controller and the supervisory controller is incorporated with the ASFNN for coping with the chattering phenomenon of the traditional sliding-mode control. In the ASFNS, an automatic structure learning mechanism is proposed for network structure optimization, where two criteria of node-adding and node-pruning are introduced. It enables the ASFNN to determine the nodes autonomously while ensures the control performance. In the ASFNS, all the parameters are evolved by the means of the Lyapunov theorem and back-propagation to ensure the system stability. Thus, an intelligent control approach for adaptive control is presented, where the structure and parameter can be evolved simultaneously. The proposed ASFNS features the following salient properties: (1) on-line and model-free control, (2) relax design in controller structure, (3) overall system stability. To investigate the capabilities, the ASFNS is applied to a kind of nonlinear system control. Through the simulation results the advantages of the proposed ASFNS can be validated.  相似文献   

17.
An adaptive sliding mode trajectory tracking controller is developed for fully-actuated robotic airships with parametric uncertainties and unknown wind disturbances. Based on the trajectory tracking model of robotic airships, an adaptive sliding mode control strategy is proposed to ensure the asymptotic convergence of trajectory tracking errors and adaptive estimations. The crucial thinking involves an adaptive scheme for the controller gains to avoid the off-line tuning. Specially, the uncertain physical parameters and unknown wind disturbances are rejected by variable structure control, and boundary layer technique is employed to avoid the undesired control chattering phenomenon. Computer experiments are performed to demonstrate the performance and advantage of the proposed control method.  相似文献   

18.
Gas flow has fractional order dynamics; therefore, it is reasonable to assume that the pneumatic systems with a proportional valve to regulate gas flow have fractional order dynamics as well. There is a hypothesis that the fractional order control has better control performance for this inherent fractional order system, although the model used for fractional controller design is integer order. To test this hypothesis, a fractional order sliding mode controller is proposed to control the pneumatic position servo system, which is based on the exponential reaching law. In this method, the fractional order derivative is introduced into the sliding mode surface. The stability of the controller is proven using Lyapunov theorem. Since the pressure sensor is not required, the control system configuration is simple and inexpensive. The experimental results presented indicate the proposed method has better control performance than the fractional order proportional integral derivative (FPID) controller and some conventional integral order control methods. Points to be noticed here are that the fractional order sliding mode control is superior to the integral order sliding mode counterpart, and the FPID is superior to the corresponding integral order PID, both with optimal parameters. Among all the methods compared, the proposed method achieves the highest tracking accuracy. Moreover, the proposed controller has less chattering in the manipulated variable, the energy consumption of the controller is therefore substantially reduced.  相似文献   

19.
为了实现基于非训练数据的神经模糊控制器的在线学习,提出了一种基于强化学习的神经模糊控制系统和相应的学习算法。该控制系统由神经模糊预测器和神经模糊控制器两部分组成,其中,神经模糊控制器采用基于确定度的模糊规则模型作为知识表示形式的扩展型神经模糊网络。在学习算法的设计中,尝试了利用强化信号得到输入状态的“期望输出”,进而将强化学习转化为基于训练数据学习的解决思路。仿真实验验证了所提出的控制系统结构和学习算法的合理性和可行性。  相似文献   

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