Unified Control Theory from PID to ACPID

To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering.

Evaluation of the Validity of Chaos Theory Based on Systems Thinking for Non-Physicists

Chaos theory was born in the 18th century, physicists still solve the nonlinear dynamic systematic problems within closed-loop systems such as ecosystems, three-body problems involving complexity, and others. Moreover, it has been resolved these problems based on logical thinking using logical solutions with algebra and statistics such as chaos theory. The reason is determinism. Nevertheless, other scientists do not welcome the old chaos theory because the chaos theory is very imperfect and vague. Amazingly, in 2021, there is emerged, and an advanced and systematic solution based on system thinking;it was resolved by a non-physicist on behalf of physicists through interdisciplinary science and it is more perfect than the old chaos theory. Therefore, it is similar to the New World discovered by Columbus. This paper will prove that the existing chaos theory is invalid as a new solution emerges. Nevertheless, current physicists avoid approaching this study as much as possible. Therefore, other scientists have no reason to follow their invalid chaos theory unless physicists prove the validity of chaos theory.

Dissipative-based adaptive neural control for nonlinear systems

A dissipative-based adaptive neural control scheme was developed for a class of nonlinear uncertain systems with unknown nonlinearities that might not be linearly parameterized. The major advantage of the present work was to relax the requirement of matching condition, i.e., the unknown nonlinearities appear on the same equation as the control input in a state-space representation, which was required in most of the available neural network controllers. By synthesizing a state-feedback neural controller to make the closed-loop system dissipative with respect to a quadratic supply rate, the developed control scheme guarantees that the L2-gain of controlled system was less than or equal to a prescribed level. And then, it is shown that the output tracking error is uniformly ultimate bounded. The design scheme is illustrated using a numerical simulation.

Support Vector Machine-Based Nonlinear System Modeling and Control

This paper provides an introduction to a support vector machine, a new kernel-based technique introduced in statistical learning theory and structural risk minimization, then presents a modeling-control framework based on SVM. At last a numerical experiment is taken to demonstrate the proposed approach's correctness and effectiveness.

Advanced Studies for Resolving Nonlinear Dynamic Systems Involving Complexity Based on Systems Thinking for Non-Physicists

There are many examples of nonlinear dynamics, such as food chains or thermodynamic systems within closed-loop systems. In modern physics, these problems have been resolved based on logical thinking by using the chaos theory in statistical physics, which was arranged by classical physicists in the 17th century. However, this is a significantly erroneous problem because, in engineering science, nonlinear dynamics must be resolved and cleared using systems analysis theory based on systems thinking. It is the main concept in a new solution that is studied through interdisciplinary research;it is needed to introduce control theory into physics. In 2015, on the behalf of physicists, the author successfully resolved and achieved a new solution, which is a significant achievement in modern science. Unfortunately, physicists have not welcomed it because it is disadvantageous to them, similar to the Copernican theory. So, they themselves became outsiders. If so, non-physicists need to follow their chaos theory in physics unless they do not clarify their solution;moreover, non-physicists on behalf of physicists can use their own new solution without risk. Hence, all scientists need to learn the systems analytic method in engineering.

New Systems Solution for Resolving Nonlinear Dynamics Based on Systems Thinking

This study describes a new solution for resolving nonlinear dynamics. Surprisingly, it has been resolved and completed by non-physicists on behalf of physicists in 2021. It is a revolutionary solution like the Copernican Theory, which is perfectly different from the existing chaos theory. In the past, nonlinear dynamics has been analyzed using logical solutions, such as chaos theory, based on logical thinking. However, it is not perfect systematic solution, hence;the new solution has been analyzed and resolved by systematic analytical tool in other sciences. Then, the result is more perfect and precise than the old chaos theory. Regrettably, most physicists do not welcome this advancement, because they have primitive solutions such as chaos theory. If the new solution is true, it is very disadvantageous to them like Galileo’s heliocentric theory. Therefore, they do not welcome it and deny and reject it. Hence, they wish it to fail;moreover, they want to remain in safe zone. Unfortunately, they became outsiders because they have no ability to review new solutions. Unfortunately, we have no obligation to follow physicists. If so, non-physicists, bypassing physicists, must study independently nonlinear dynamics based on systems thinking, and have to share the findings other scientists. It means that the new solution would be replaced the chaos theory in traditional physics;moreover, it would be resolved many unsolved nonlinear dynamics in the future.

A Family of Reliable H_∞ State-Feedback Controllers for Nonlinear Systems with Strictly Redundant Actuators: the Full Information Case

The paper is concerned with the reliable H ∞ state feedback control and controller parameterization problem for nonlinear systems with strictly redundant actuators. Based on Hamilton Jacobi inequality, the sufficient condition is presented such that the reliable control problem is resolved, and a family of controllers is given such that the resulting closed loop systems are asymptotically stable and their L 2 gain is limitable not only when all actuators are operational but also when any one,but only one of actuators experiences an outage. The results of this paper provide a deep insight into the synthesis of the reliable nonlinear H ∞ state feedback.

Coordinated Frequency Control for Isolated Power Systems with High Penetration of DFIG-Based Wind Power

This paper proposes a coordinated frequency control scheme for emergency frequency regulation of isolated power systems with a high penetration of wind power.The proposed frequency control strategy is based on the novel nonlinear regulator theory,which takes advantage of nonlinearity of doubly fed induction generators(DFIGs)and generators to regulate the frequency of the power system.Frequency deviations and power imbalances are used to design nonlinear feedback controllers that achieve the reserve power distribution between generators and DFIGs,in various wind speed scenarios.The effectiveness and dynamic performance of the proposed nonlinear coordinated frequency control method are validated through simulations in an actual isolated power grid.

Bandwidth Based Stability Analysis of Active Disturbance Rejection Control for Nonlinear Uncertain Systems

This paper focuses on the stability analysis of the active disturbance rejection control (ADRC)for a class of uncertain systems.To overcome the difficulty of defining a reasonable Lyapunov function and setting limitations of system parameters,the converse Lyapunov theorem and the disturbance theory are employed.This paper proves that the estimation error of the extended state observer (ESO)and the tracking error of the closed-loop system using ADRC are uniformly ultimately bounded and monotonously diminishing with the increase of their respective bandwidth,so that the stability of the ADRC system could be performed.In order to further illustrate the relationship between the stability range and bandwidths,it analyzes quantitatively the performance of ESO and ADRC based on the root locus and the step response.Finally,an example based on a typical control system is carried out,and simulation results verify the theoretical analysis proved in this paper.

Control and Synchronization with Known and Unknown Parameters

In this paper, we consider the chaos control for 4D hyperchaotic system by two cases, known & unknown parameters based on Lyapunov stability theory via nonlinear control. We find that there are two cofactors that have an effect on determining any case to achieve the control, the two cofactors are proposed in the control and the matrix that produce from the time derivative of Lyapunov function. In adding, we find some weakness cases in Lyapunov stability theory. For this reason, we design with only one controller and perform a simple change in this control in order to recognize the difference between these cases although all of the controllers are almost similar.

Controllability of Nonlinear Discrete Systems with Degeneracy

This paper concerns the controllability of autonomous and nonautonomous nonlinear discrete systems,in which linear parts might admit certain degeneracy.By introducing Fredholm operators and coincidence degree theory,sufficient conditions for nonlinear discrete systems to be controllable are presented.In addition,applications are given to illustrate main results.

Controllability of Quantum Systems with SU(1,1)Dynamical Symmetry

This paper presents sufficient and necessary conditions for the propagator controllability of a class of infinite-dimensional quantum systems with SU(1,1)dynamical symmetry through the isomorphic mapping to the non-unitary representation of SU(1,1).The authors prove that the elliptic condition of the total Hamiltonian is both necessary and sufficient for the controllability and strong controllability.The obtained results can be also extended to control systems with SO(2,1)dynamical symmetry.

An algebraic approach to dynamic optimisation of nonlinear systems:a survey and some new results

Dynamic optimisation,with a particular focus on optimal control and nonzero-sum differential games,is considered.For nonlinear systems solutions sought via the dynamic programming strategy are inevitably characterised by partial differential equations(PDEs)which are often difficult to solve.A detailed overview of a control design framework which enables the systematic construction of approximate solutions for optimal control problems and differential games without requiring the explicit solution of any PDE is provided along with a novel design of a nonlinear control gain aimed at improving the‘level of approximation’achieved.Multi-agent systems are considered as a possible application of the theory.

齿隙非线性研究进展

系统地介绍并总结了近年来齿隙非线性控制领域的研究成果。对不同齿隙模型作了分析,总结了目前齿隙非线性的补偿方法,结合齿隙位于被控对象中不同位置的控制系统,介绍了各种控制理论和控制策略在齿隙非线性控制领域的研究进展,并展望了该领域未来的研究方向。

非线性系统有限时间控制研究综述

近30年来,有限时间控制因其具有收敛速度快、抗扰性强、控制精度高等优点,引起了学者们的研究兴趣.据作者所知,目前鲜有文献系统地总结有限时间控制的相关研究内容.因此,本文致力于较为系统且完整地给出非线性系统有限时间控制方法的研究进展.主要内容包括如下几方面:研究意义;有限时间的定义,判据及设定时间表达式;有限时间设计方法的研究现状以及未来工作.

战术导弹现代自动驾驶仪设计方法综述

对近几年国外报道的基于现代控制理论的导弹自动驾驶仪的设计方法:动态逆、滑模变结构、非线性H∞、神经网络、状态R icatti方程、线性变参数方法就原理、实施、发展动向、存在的问题进行了综述,对这些方法在导弹自动驾驶仪的具体设计中的优缺点进行了简要的总结,指出了各种方法急需解决的问题,并对如何克服相应的缺点给出了建议性的方向。

一般模型控制(GMC):一种简单实用的非线性过程控制新方法

一般模型控制（ＧｅｎｅｒｉｃＭｏｄｅｌＣｏｎｔｒｏｌ－ＧＭＣ）是１９８８年以来发展起来的一种非线性过程控制方法，此方法具有简单实用，鲁棒性强的特点，而其控制效果却与微分几合方法相类似，因此在过去的九年里此方法已得到广泛的应用．本文综述了此方法的发展状况，并指出了尚待解决的若干问题．

低速行驶重型车辆的动力学系统建模与非线性控制

考虑低速行驶工况下的重型车辆,本文建立其纵向行驶驱/制动系统的非线性动力学方程．在此基础上采用反馈线性化方法将驱/制动工况下的非线性系统转化为线性可控正则型,并针对制动工况下非线性系统存在的控制时滞,提出一种基于非线性SMITH预估方法的反馈线性化变换,该变换在有效补偿控制时滞同时,实现了制动系统的线性可控正则型转换．最后,分别基于驱/制动系统的线性可控正则型设计跟踪控制器,实现了车辆低速工况的加/减速度精确跟踪控制．

低速风洞绳牵引并联支撑系统的机构与模型姿态控制方案设计

首先介绍作为风洞试验中新型'软式'支撑系统的绳牵引并联支撑系统;其次,在给定的设计要求下,依据缩比模型所需运动,探讨绳牵引并联支撑系统的设计原理,并提出详细的设计步骤,得到了一个8根绳牵引的RRPM:WDPSS-8,使缩比为1∶40的F-15E模型可实现的俯仰角达-79°～71°、滚转角达-90°～90°、偏航角达-38°～39°;最后,在建立系统的动力学模型的基础上,采用基于绳长关节空间的驱动力矩控制器的位置控制方案来进行缩比模型的姿态控制,并用Lyapunov函数证明缩比模型在该控制规则下的运动稳定性.

深海系泊系统动张力有限元计算

考虑深海聚酯尼龙系泊缆的拉伸和弯曲变形,取正交坐标和切向量描述任意结点的6个广义位移,缆变形的几何非线性,基于细长杆理论推导缆索单元的刚度矩阵和质量矩阵,得到12×12的非线性单元特性矩阵,利用有限元软件计算系泊系统的动张力。针对水深1 800 m由12根缆定位的Spar平台,考虑水流对系泊系统的作用,计算了不同外激励下的系缆动张力,讨论了激励频率对系缆张力的影响。结果表明,建立的缆索单元特性矩阵可以较好模拟深海聚酯缆的力学性能,并且得到的深海系泊缆动张力变化规律和力学特性是合理的。