Passive adaptive control of chaos in synchronous reluctance motor

The performance of synchronous reluctance motor （SynRM） degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in SynRM, a passive control law is presented in this paper, which transforms the chaotic SynRM into an equivalent passive system. It is proved that the equivalent system can be asymptotically stabilized at the set equilibrium point, namely, chaos in SynRM can be controlled. Moreover, in order to eliminate the influence of undeterministic parameters, an adaptive law is introduced into the designed controller. Computer simulation results show that the proposed controller is very effective and robust against the uncertainties in systemic parameters. The present study may help to maintain the secure operation of industrial servo drive system.

Adaptive synchronization of chaos in permanent magnet synchronous motors based on passivity theory

An adaptive synchronization control method is proposed for chaotic permanent magnet synchronous motors based on the property of a passive system. We prove that the controller makes the synchronization error system between the driving and the response systems not only passive but also asymptotically stable. The simulation results show that the proposed method is effective and robust against uncertainties in the systemic parameters.

Passive control of Permanent Magnet Synchronous Motor chaotic systems

Permanent Magnet Synchronous Motor model can exhibit a variety of chaotic phenomena under some choices of system parameters and external input. Based on the property of passive system, the essential conditions were studied, by which Permanent Magnet Synchronous Motor chaotic system could be equivalent to passive system. Using Lyapunov stability theory, the convergence condition deciding the system's characters was discussed. In the convergence condition area, the equivalent passive system could be globally asymptotically stabilized by smooth state feedback.

Passive control of Permanent Magnet Synchronous Motor chaotic system based on state observer

Passive system theory was applied to propose a new passive control method with nonlinear observer of the Permanent Magnet Synchronous Motor chaotic system. Through constructing a Lyapunov function, the subsystem of the Permanent Magnet Synchronous Motor chaotic system could be proved to be globally stable at the equilibrium point. Then a controller with smooth state feedback is designed so that the Permanent Magnet Synchronous Motor chaotic system can be equivalent to a passive system. To get the state variables of the controller, the nonlinear observer is also studied. It is found that the outputs of the nonlinear observer can approximate the state variables of the Permanent Magnet Synchronous Motor chaotic system if the system’s nonlinear function is a globally Lipschitz function. Simulation results showed that the equivalent passive system of Permanent Magnet Synchronous Motor chaotic system could be globally asymptotically stabilized by smooth state feedback in the observed parameter convergence condition area.

Passive control and synchronization of hyperchaotic Chen system

This paper investigates the control and synchronization of hyperchaotic Chen system based on the passive theory. By using two outputs, novel passive controllers are respectively designed to realize the globally asymptotical stability of the hyperchaotic Chen system and the error dynamical system, which avoids mistakes in Ref.[11], where function W（z） cannot guarantee that fo（z） is globally asymptotically stable via only one output and W（z） is the Lyapunov function of f0（z）. Furthermore, numerical simulations are given to show the effectiveness of our method.

Adaptive synchronization of a hyperchaotic L system based on extended passive control

This paper investigates the adaptive synchronization of hyperchaotic Lii systems based on the method of extended passive control. By combining the feedback control, the extended passive control method with two output variables is developed, which can synchronize hyperchaotic Lu systems asymptotically and globally more easily without knowing the bound of state of the hyperchaotic system. Adaptive laws are introduced to estimate the unknown parameters as well. Simulation results show the effectiveness and flexibility of the proposed control scheme.

Generalized passivity-based chaos synchronization

In this paper, a new passivity-based synchronization method for a general class of chaotic systems is proposed. Based on the Lyapunov theory and the linear matrix inequality （LMI） approach, the passivity-based controller is presented to make the synchronization error system not only passive but also asymptotically stable. The proposed controller can be obtained by solving a convex optimization problem represented by the LMI. Simulation studies for the Genesio-Tesi chaotic system and the Qi chaotic system are presented to demonstrate the effectiveness of the proposed scheme.

组合弹性无缘轮半被动行走的混沌和同步分析

本文提出了组合弹性无缘轮模型,通过加入周期振荡的间接控制,实现了组合弹性无缘轮的半被动行走.通过观察组合弹性无缘轮半被动行走的步态,分析了混沌和同步化的非线性行为.首先,建立组合弹性无缘轮半被动行走的动力学模型,使其能够实现稳定的周期行走;其次,通过对组合弹性无缘轮半被动行走的典型步态分析,表明极限环的稳定性对初始条件敏感;最后,通过观察组合弹性无缘轮半被动行走的步态,分析振荡频率与系统行走频率关系,以及振荡频率与系统行走频率的相位差与行走步数之间是否存在同步化和混沌等非线性行为.仿真结果表明,对于振荡频率与系统行走频率之间的关系,较轻的摆动质量和较小的摆动振幅呈现出同步化现象,较重的摆动质量和较大的摆动振幅呈现出混沌现象;对于振荡频率与系统行走频率的相位差与行走步数的关系,较轻的摆动质量和较小的摆动振幅呈现出混沌现象.

无源多动子永磁同步直线电机定位方法研究

为实现永磁同步直线电机系统中对多个无源动子的绝对定位,设计了基于双磁道的短磁栅、长传感器定位方案。双磁道包括增量式磁道和绝对式磁道,每个磁道中的短磁栅为永磁体阵列,长传感器内霍尔阵列由线性霍尔芯片组成,且长传感器包含多个线性霍尔阵列。其中,增量式磁道采用区间查表方式计算位移增量,绝对式磁道采用连续位移编码方式识别绝对偏移量。定子传感器数字信号输出的霍尔芯片阵列与主控MCU之间通过总线方式连接,且信号处理和传输均在MCU中进行,简化了硬件电路。结果表明,无源多动子绝对位置传感器具有不同应用场景便于移植的特点,使无源动子的定位更灵活。

H_(∞)/Passive Synchronization of Semi-Markov Jump Neural Networks Subject to Hybrid Attacks via an Activation Function Division Approach

In this work,an H_(∞)/passive-based secure synchronization control problem is investigated for continuous-time semi-Markov neural networks subject to hybrid attacks,in which hybrid attacks are the combinations of denial-of-service attacks and deception attacks,and they are described by two groups of independent Bernoulli distributions.On this foundation,via the Lyapunov stability theory and linear matrix inequality technology,the H_(∞)/passive-based performance criteria for semi-Markov jump neural networks are obtained.Additionally,an activation function division approach for neural networks is adopted to further reduce the conservatism of the criteria.Finally,a simulation example is provided to verify the validity and feasibility of the proposed method.

硅-钙土壤调理剂阻控复合污染稻米镉砷积累的研究

为探究硅-钙土壤调理剂(Ca-Si)对镉砷复合污染水稻积累镉砷(Cd、As)的影响研究,以“泰优390”为试验品种,采用随机区组试验设计,选取3处(浏阳LY、临武LW和慈利CL)镉砷复合污染耕地开展田间试验。结果表明:硅-钙土壤调理剂施用下的水稻产量略有增幅(4.18%~11.26%);能有效阻控水稻对Cd、As积累,显著降低稻米中Cd、As的含量,通过镉砷同步钝化综合效果评价,LY、LW和CL的Cd、As降幅分别为40.63%、21.62%和41.67%,及29.51%、25.20%和15.38%;通过镉砷同步钝化综合效果评价,LY、LW和CL的Cd-As同步降低效果分别为33.40%、23.95%和24.58%,效果显著。因此,硅-钙土壤调理剂在镉砷复合污染耕地上能同步降低稻米的镉砷含量。

基于分离源矩阵变换器的PMSM无源动态演化控制策略

为了改进传统的永磁同步电机驱动器系统及其PID控制的不足,提出了一种无源动态演化控制策略,并应用于永磁同步电机(permanent magnet synchronous motor,PMSM)和分离源矩阵变换器(split source matrix con-verter,SSMC)中。为打破传统矩阵变换器电压传输比0.866的限制,采用电感、电容和3个二极管代替了双级矩阵变换器中间的支流链路部件,并且证明了分离源网络的升压能力。另外,在矢量控制中,永磁同步电机的转速外环和电流内环都使用了传统PID控制器,但由于PID控制器的参数调节比较困难、控制精度不高、超调量较大和抗干扰能力不强等问题,为此提出了基于动态演化理论和无源理论的控制策略,设计了分离源矩阵变换器和永磁同步电机系统基于互联和阻尼分配(the interconnection and damping assignment,IDA)的无源控制器(passivity-based control,PBC)和动态演化控制器(dynamic evolution controller,DEC)。仿真与实验的结果表明,基于该控制策略的SSMC-PMSM驱动系统能够使永磁同步电机稳定运行在额定转速,并且具有稳定性强、抗干扰能力强和动态响应好等特点。

基于模糊自抗扰的无源控制及其在舰载火箭炮位置伺服系统中的应用

介绍了一种基于模糊自抗扰控制(FADRC)的新型无源控制(PBC),该控制利用改进粒子群优化(IPSO)算法进行优化,并应用于由永磁同步电机(PMSM)驱动的舰载火箭炮位置伺服系统。基于互联与阻尼配置的无源控制(IDA-PBC)理论,采用端口受控耗散哈密顿(PCHD)方法,对永磁同步电机进行建模。为了改善传统ADRC的鲁棒性和动态性能,利用模糊控制对非线性状态误差反馈(NLSEF)的比例系数进行实时调整。此外,采用IPSO算法对5个模糊控制参数进行在线优化,以保证控制系统的快速性和全局最优性。仿真实验表明,与ADRC-PBC和FADRC-PBC控制器相比,所提出的IPSO-FADRC-PBC控制器具有更好的静态和动态性能。

Influence of Synchronization Impairments on an Experimental TDOA/FDOA Localization System

In Electronic Warfare, and more specifically in the domain of passive localization, accurate time synchronization between platforms is decisive, especially on systems relying on TDOA （time difference of arrival） and FDOA （frequency difference of arrival）. This paper investigates this issue by presenting an analysis in terms of final localization performance of an experimental passive localization system based on off-the-shelf components. This system is detailed, as well as the methodology used to carry out the acquisition of real data. This experiment has been realized with two different kinds of clock. The results are analyzed by calculating the Allan deviation and time deviation. The choice of these metrics is explained and their properties are discussed in the scope of an airborne bi-platform passive localization context. Conclusions are drawn regarding the overall localization performance of the system.

基于无源控制的DFIG并网次同步控制相互作用抑制策略研究

为抑制双馈感应发电机(doubly-fed induction generator,DFIG)风电场与串补输电线路间次同步控制相互作用(sub-synchronous control interaction,SSCI),提出基于改进无源控制的SSCI抑制策略。首先,分析了DFIG并网中SSCI发生机理,发现转子侧变流器双环PI控制对SSCI影响较大,可对PI控制进行改进以抑制SSCI。其次,基于DFIG欧拉-拉格朗日(Euler-Lagrange,EL)模型和无源理论,设计转子侧无源控制器,通过计算稳定状态点,注入阻尼抑制SSCI。为提高抑制能力,采用带通滤波器改进无源控制,通过保持输入信号稳定提升控制器性能。最后,给出小干扰分析和时域仿真分析结果,并与PI控制和常规无源控制对比,验证所提策略在串补度变化和风速变化时的抑制效果。

带有滑模软切换的永磁同步电机无源控制

设计了一种带有滑模软切换的永磁同步电机无源控制系统,构建了永磁同步电机无源控制系统模型,设计了稳定收敛的无源控制器。结合电机摄动参数,给出了滑模软切换控制器和滑模观测器的设计方法。通过仿真算例验证该控制策略可以有效减小系统的抖振,滑模软切换控制与无源控制器能够协调配合,提高系统的鲁棒性,取得更好的动、静态调速性能。

基于蓝牙的手部外骨骼体感同步控制设计

现如今,中国人均寿命普遍增长,老年人群体逐渐扩大,2021年已增长到2.1亿。快速老龄化容易导致更多人群出现脑部疾病或关节老化,而对上肢康复服务的需求不断增大。目前,主要的治疗方法如:服用神经营养药,针灸按摩等,能在一定程度上缓解症状,但想要完全恢复还需要加强肌肉的主动和被动活动,促进肌肉抗力,拉力和压应力的恢复。这就需要通过康复训练来完成。为解决上述问题,本项目基于Arduino系统设计构建了一种基于蓝牙的外骨骼手控制系统,可以通过蓝牙HC-05来连接外骨骼手,从而完成腕部旋转,手指运动,抓取物体等生活常用功能。并增加体感遥控设计,通过手的动作直接控制外骨骼手,增加患者主动康复训练的意愿。通过蒙特卡洛法在Matlab中对该外骨骼收进行空间上的仿真,验证了本设计能有效地辅助康复患者的手指运动,能够完成日常生活用品的抓取。通过理论推导与体感手部外骨骼实验数据表明该控制系统设计合理,能够在后续该机械手的临床实验中,提高康复患者的训练质量,在手康复训练中起到积极的作用。

连续施用镉砷同步钝化剂的稻米镉砷含量降低效果分析

选择湖南典型镉砷复合污染稻田,通过2018—2020年连续3 a的大田定位试验对10个镉砷同步钝化产品进行效果验证,为镉砷同步钝化产品连续施用的持续效果及镉砷复合污染稻田产品的选择提供参考。结果表明:10个钝化剂产品均具有同步降低稻米镉砷含量的效果,但不同钝化剂的稻米降镉、降砷效果不同,稻米降镉效果最好的是T9处理,3 a平均稻米降镉率为52.42%;其次是T4和T3,3 a平均稻米降镉率分别为42.62%和40.96%;稻米降砷效果最好的为T7和T4处理,3 a平均稻米降砷率分别为34.15%和33.32%;整体上,钝化剂降低稻米镉含量的效果高于降砷的效果,且钝化剂的连续施用对稻米降镉和降砷皆具有一定的累加效应;另外,连续施用3 a钝化剂在一定程度上提升了土壤的pH值,且2018—2020年稻米镉含量皆与土壤pH值呈显著负相关,表明施用钝化剂提升了土壤pH值,并抑制了水稻对镉的吸收积累。综合考虑认为,T4、T8、T7和T10处理的钝化剂产品适用于镉砷复合污染土壤的修复治理,T9等其他处理的钝化剂产品适用于单镉污染耕地的修复治理。

基于虚拟同步发电机和无源性控制的DFIG机侧控制策略

传统的双馈感应发电机(doubly-fed induction generator,DFIG)矢量控制因其惯性与电网频率波动解耦而不能为电网提供额外的有功功率支持,为此在DFIG转子侧变流器控制中引入一种改进的虚拟同步发电机(virtual synchronous generator,VSG)控制策略。针对传统VSG控制存在的频率偏差问题,通过在有功下垂环节中加入一个Washout滤波器,实现了在不需要增加额外2次控制回路情况下就能使频率保持在工频50 Hz附近。同时,为解决传统VSG中电压电流双环控制中内环电流PI控制存在的动态响应有限、鲁棒性不强等问题,首次在内环电流控制中引入了基于端口受控的耗散哈密顿(port controlled Hamiltonian with dissipation,PCHD)模型的无源性控制(passivity-based control,PBC)方法,设计了转子侧变流器的无源性控制器。最后,搭建了DFIG仿真系统进行实验验证,结果表明了本文所提控制策略的有效性和优越性。

无人机编队飞行中的定位和同步控制问题研究

主要研究无人机在编队飞行时的纯方位无源定位问题和保持固定队形的同步控制问题。首先,通过被动接收信号无人机接收到的位置信息建立纯方位无源定位的非线性规划模型,利用变步长搜索法进行求解,得到了误差较小的定位位置。然后,结合一个特定的编队方式,利用纯方位无源定位方法建立无人机飞行过程中的多智能体同步控制模型,实现了通过较少的调整次数将有偏差的无人机调整至理想位置。最后,通过仿真实验验证了模型和算法的有效性。