Zero/pole placement control of periodic duct noise

A zero/pole placement controller (ZPPC) is presented here for active control of periodic duct noise. It uses sound pressure feedback instead of modal feedback. The controller is able to place closed-loop zeros in addition to closed-loop poles. A new adaptation law is proposed to help the controller to track parameter drifting and maintain good performance. The controller can combine with any feedforward scheme to form a hybrid (feedforward/feedback) active noise controller. It has an advantage of on-line identification of the secondary path without persistent excitations.     

Generalisation and optimisation of semi-active, on-off switching controllers for single degree-of-freedom systems

This paper examines generalised forms of semi-active switching control in comparison to the sky-hook semi-active controller. A switching time controller is proposed and analysed, in order to determine the optimal performance, with regard to displacement transmissibility, of semi-active switching control. In addition, the model is also used to assess the optimality of the sky-hook switching conditions. An analytical solution is then derived for the optimal switching times. A generalised form of linear switching surface controller is then presented. It is demonstrated that this controller can produce near optimal performance.     

A Simplified Fractional Order PID Controller’s Optimal Tuning: A Case Study on a PMSM Speed Servo

A simplified fractional order PID (FOPID) controller is proposed by the suitable definition of the parameter relation with the optimized changeable coefficient. The number of the pending controller parameters is reduced, but all the proportional, integral, and derivative components are kept. The estimation model of the optimal relation coefficient between the controller parameters is established, according to which the optimal FOPID controller parameters can be calculated analytically. A case study is provided, focusing on the practical application of the simplified FOPID controller to a permanent magnet synchronous motor (PMSM) speed servo. The dynamic performance of the simplified FOPID control system is tested by motor speed control simulation and experiments. Comparisons are performed between the control systems using the proposed method and those using some other existing methods. According to the simulation and experimental results, the simplified FOPID control system achieves the optimal dynamic performance. Therefore, the validity of the proposed controller structure and tuning method is demonstrated.     

直膨式空调人工神经网络在线自适应控制器应用研究

直接膨胀式空调系统人工神经网络控制器已经有了一些研究成果,为了解决控制器控制范围和精度的问题,引入在线自适应控制系统。该控制器的控制能力测试采用直接膨胀式空调系统实验装置进行。试验结果表明,基于人工神经网络动态模型的在线自适应控制器进行训练的前提下,该控制器能够将室内空气的干球和湿球温度控制在一定范围内,具有较高的控制精度。     

基于改进射影控制的降阶高压直流附加控制器设计

针对电力系统控制器设计中,控制器阶数过高且影响控制品质的问题,提出一种基于射影定理的降阶控制器设计新方法,并对射影定理做出改进,实现抑制低频振荡的高压直流附加阻尼控制.通过总体最小二乘-旋转不变技术分析系统振荡特性并辨识出相关模型,再基于极点配置得到状态反馈矩阵,最后利用改进的射影控制理论设计输出反馈降阶控制器,同时将控制器与传统的带观测器的极点配置控制方法进行比较.仿真验证表明,基于射影控制理论的控制器效果较好,控制器阶数较低,鲁棒性强,便于工程实现.     

Network-based modelling and active control for offshore steel jacket platform with TMD mechanisms

The network-based modelling and active control for an offshore steel jacket platform with an active tuned mass damper mechanism is investigated. A network-based dynamic model of the offshore platform is first established. A network-based state feedback control scheme is developed. Under this scheme, the corresponding closed-loop system is modelled by a system with an artificial interval time-varying delay. Then, a delay-dependent stability criterion for the corresponding closed-loop system is derived. Based on this stability criterion, a sufficient condition on the existence of the network-based controller is obtained. It is found through simulation results that (i) both the oscillation amplitudes of the offshore platform and the required control force under the network-based state feedback controller are smaller than those under the nonlinear controller and the dynamic output feedback controller; (ii) the oscillation amplitudes of the offshore steel jacket platform under the network-based feedback controller are almost the same as the ones under the integral sliding mode controller, while the required control force by the former is smaller than the one by the latter.     

Chattering alleviation in vibration control of smart beam structures using piezofilm actuators: Experimental verification

This paper presents a new discrete-time sliding mode controller to alleviate undesirable chattering in vibration control of a flexible beam structure. A smart beam featuring a piezoelectric film is devised and its governing equation of motion is derived. A discrete-time sliding mode controller which consists of discontinuous part and equivalent part is then designed by considering the separation principle. By doing this, undesirable chattering of the beam structure can be attenuated in the settled phase. The proposed controller is experimentally realized, and both transient and forced vibration control responses are evaluated in time domain.     

混沌系统的变论域模糊控制算法研究

混沌运动和混沌控制受到广泛关注,本文利用模糊控制实现混沌系统的控制.针对模糊控制器精度不高,模糊控制中规则数量与控制精度之间的矛盾,提出了一种基于蚁群优化算法的变论域模糊控制器.通过分析变论域模糊控制中的2类伸缩因子,指出其中1类并不能满足广义伸缩因子条件.提出利用蚁群优化算法对伸缩因子智能寻优的方法,在对蚁群算法改进的基础上,构成一种基于蚁群算法的变论域模糊控制,将设计的控制器用于Duffing混沌系统的控制.仿真结果表明,提出的控制算法在收敛速度和稳态性能上要略优于其他控制方式. 关键词： 混沌 变论域模糊控制 伸缩因子 蚁群优化算法     

利用x|x|控制混沌系统

提出了一种新的混沌控制方法，即对混沌动力系统增加一个具有分段二次函数x|x|形式的非线性反馈控制器，利用它控制了一大类系统从混沌运动转化为各种规则的运动.该控制器是一种活动控制器，它不影响原系统的参数，其结构相当简单而且在物理、电路上都容易实现.数值仿真表明了该控制方法的有效性与可行性. 关键词： 混沌 非线性反馈控制器 分段二次函数     

参数不确定永磁同步电机混沌系统的有限时间稳定控制

针对含有参数不确定性的永磁同步电机混沌系统, 结合主动控制与有限时间稳定控制理论, 提出一种改进的主动有限时间稳定控制器. 该控制器不仅具有较强的鲁棒性, 而且可以通过调整终端吸引子比例系数, 有效地缩短系统的响应时间, 以提高系统的响应能力. 通过仿真实验, 验证了该控制器比传统的控制器的具有更强的鲁棒性和响应能力. 关键词： 永磁同步电机 混沌控制 有限时间稳定 主动控制     

A tunable comb filter using single-mode/multimode/polarization-maintaining-fiber-based Sagnac fiber loop

A novel tunable comb filter composed of a single-mode/multimode/polarization-maintaining-fiber-based Sagnac fiber loop is proposed and experimentally demonstrated. The filter tunability is achieved by rotating the polarization controller. The spectral shift is dependent on rotation direction and the position of the polarization controller. In addition, the adjustable range achieved by rotating the half-wave-plate polarization controller is twice higher than that of the quarter-wave-plate one.     

利用单模激光Lorenz系统实现异结构混沌系统混沌同步

对混沌同步问题进行了研究。设计了一种同步控制器来实现异结构混沌系统之间的混沌同步。减少了控制器的数量,仅用一个控制器就能实现这一同步控制。同时,控制器只需在目标和响应系统中提取一个易提取信号即可实现,从而大大降低了同步代价,便于实际应用。以单模激光Lorenz系统和coullet系统为例,验证了这种控制器的有效性。仿真模拟结果表明,在控制器的作用下,coullet系统所有状态变量严格地跟踪了单模激光Lorenz系统的混沌轨迹,两者迅速地达到完全同步。该设计的控制方法可用于任意混沌系统,具有一定的普适性。     

Comparison between two different sliding mode controllers for a fractional-order unified chaotic system

Two different sliding mode controllers for a fractional order unified chaotic system are presented. The controller for an integer-order unified chaotic system is substituted directly into the fractional-order counterpart system, and the fractional-order system can be made asymptotically stable by this controller. By proving the existence of a sliding manifold containing fractional integral, the controller for a fractional-order system is obtained, which can stabilize it. A comparison between these different methods shows that the performance of a sliding mode controller with a fractional integral is more robust than the other for controlling a fractional order unified chaotic system.     

嵌入式电子节能控制器的设计与实现

节能控制能够有效降低能耗,对保护环境等方面具有重要影响。但目前大多数电子节能控制器都是通过采用单片机技术和双向晶闸管过零触发交流调压电路对电子节能控制器进行设计。通过介绍电子的负荷特点和节能原理,分析电子节能控制器的硬件组成电路,并对电子节能控制器的主要软件程序的流程图进行设计,完成电子节能控制器设计。但这种方法节能控制效果较低,难以保证电子节能控制器性能,为此,提出一种基于模糊PID控制的嵌入式电子节能控制器设计与实现方法。首先通过对嵌入式电子节能控制器的处理器、电源电路、复位电路、系统时钟电路、JTAG接口电路、D/A转换电路、功放电路、双极性电源电路以及嵌入式电子节能控制器硬件PCB板器件布局等的设计,完成嵌入式电子节能控制器硬件设计。在此基础上,选用模糊PID控制方法对嵌入式电子节能控制器进行设计。通过分析模糊PID控制原理,介绍加入自调节因子的模糊PID控制的算法设计,以此确定输入输出隶属度函数,再利用模糊推理和模糊规则,得到电子节能控制器的模糊控制过程,从而完成嵌入式电子节能控制器的设计。实验证明,所提方法能够有效提高嵌入式电子节能控制器的节能控制效果,具有良好的使用价值。     

Tracking control and synchronization of four-dimensional hyperchaotic Rossler system

In this paper we study the problem of the four-dimensional hyperchaotic Rossler system tracking control. A controller based on the reference signal is designed. It is theoretically proved that the controller can make the error converge to zero exponentially. Numerical results have verified the validity of the controller. The Rossler system cannot only track any reference signal fast, but can synchronize with identical or different chaotic systems.     

有源消声耳罩控制器的实现

本文用传递函数描述了复合式有源消声耳罩的系统模型,确定了模拟式消声控制器的合理阶次,对于前馈控制器和反馈控制器,均比出了电路实现方案,最后,实际设计了复合式有源消声耳罩,并实测了控制器特性和消声效果,验证了本文提出了的控制器实现方法的有效性。     

Finite-time control of chaotic systems with nonlinear inputs

A finite-time controller is designed for a class of nonlinear systems subject to sector nonlinear inputs. A novel and simple approach is suggested based on the finite-time control principle. The designed sliding-mode controller can drive a chaotic system to track a smooth target signal in a finite time. The chaotic Duffing--Holmes oscillator is used for verification and demonstration.     

模拟退火算法在无端偏振控制器中的应用

构造了由四个相移范围在0~2π的电光晶体波片组成的偏振控制器,利用模拟退火法作为其反馈控制算法.仿真计算表明,该偏振控制器是无端的,在较优的控制参量下,其输出的偏振态是稳定的,光强波动小于1%.对于四波片偏振控制器,模拟退火算法的控制参量研究表明,为得到较佳的控制效果,可把内外循环次数各限制为3次,以减少处理器时间;其初温T0应取在0.1附近;温度更改常数p宜取在0.2左右;状态产生常数s对输出的稳定性影响最大,仿真说明设在 0.005~0.01间为好.     

Smooth control of HIV/AIDS infection using a robust adaptive scheme with decoupled sliding mode supervision

In this paper, a robust adaptive controller subject to decoupled sliding mode controller as a supervisory controller has been implemented on the HIV infection dynamic model. A five-state dynamic model of HIV is utilized which the measurement of the CD4+T cells and the viral load counts are necessary to estimate all its parameters. Decoupled sliding mode control is a variable structure controller having significant and appropriate features, such as best tracking and regulation performance and robustness and elevate the performance of the controller. Generally, due to the importance of applied treatment strategy to mitigate viral escape, sliding mode control is utilized in accordance with PI control to deliver necessary control inputs. To achieve the least possible chattering, effectual methods such as the transfer function is used. To update the gains of PI control, an adaptation law is then employed. The results demonstrate the suitable performance of the controller via providing proper tracking performance, and also, elimination of the chattering problem and decrease the time of treatment. The number of infected CD4+ T-cells and the number of free virus particles can be controlled in less than five days. The proposed controller is capable of controlling the dynamic behavior of the virus concentration for different patients with the same control scheme.     

不确定自催化反应扩散时空混沌系统的延时同步

设计了一种延迟同步控制器实现了时空混沌系统之间的同步控制.基于Lyapunov稳定性定理,确定了延迟同步控制器的结构以及系统状态变量之间的误差方程.以自催化反应扩散时空混沌系统为例,仿真模拟验证了该控制器的有效性.进一步设计了参量辨识器,对不确定自催化反应扩散时空混沌系统中的参量进行了有效辨识.通过研究有界噪声影响下系统的同步效果,表明该同步方法具有较好的抗干扰能力. 关键词： 时空混沌 延时同步 参量辨识 有界噪声