Adaptive back-stepping pitch angle control for wind turbine based on a new electro-hydraulic pitch system

A new electro-hydraulic pitch system is proposed to smooth the output power and drive-train torque fluctuations for wind turbine. This new pitch system employs a servo-valve-controlled hydraulic motor to enhance pitch control performances. This pitch system is represented by a state-space model with parametric uncertainties and nonlinearities. An adaptive back-stepping pitch angle controller is synthesised based on this state-space model to accurately achieve the desired pitch angle control regardless of such uncertainties and nonlinearities. This pitch angle controller includes a back-stepping procedure and an adaption law to deal with such uncertainties and nonlinearities and hence to improve the final pitch control performances. The proposed pitch system and the designed pitch angle controller have been validated for achievable and efficient power and torque regulation performances by comparative experimental results under various operating conditions.     

Data-driven simulation and control

Classical linear time-invariant system simulation methods are based on a transfer function, impulse response, or input/state/output representation. We present a method for computing the response of a system to a given input and initial conditions directly from a trajectory of the system, without explicitly identifying the system from the data. Similar to the classical approach for simulation, the classical approach for control is model-based: first a model representation is derived from given data of the plant and then a control law is synthesised using the model and the control specifications. We present an approach for computing a linear quadratic tracking control signal that circumvents the identification step. The results are derived assuming exact data and the simulated response or control input is constructed off-line.     

A new sliding mode controller for wind turbine pitch angle control

This paper focuses on variable-speed wind turbines where control is aimed at stabilizing the output power. A hybrid control algorithm is proposed which includes a new arrangement of two controllers along with an observer. Estimation of power coefficient via sliding mode observer reduces the amount of errors caused by changing the power coefficient parameter in different turbines. Moreover, the use of this special arrangement of sliding mode controller, proportional-integral (PI) controller and sliding mode observer, removes one of the controller parameter denoting wind speed from the designed algorithm, which in turn eliminates disturbances related to wind speed changes. In order to show the efficiency of the proposed control method, the performances of the controllers are evaluated by simulation in MATLAB software.     

改进PID的无人机飞行姿态角控制消颤算法

无人机在整个纵平面飞行过程中,由于飞行姿态角的大幅度变化以及气流的作用,导致机身颤抖,影响飞行稳定性.提出一种基于PID变结构控制的无人机飞行姿态角控制消颤算法,首先进行了无人机飞行姿态角控制系统的被控对象参量分析,构建无人机在姿态角变化剧烈、大迎角飞行时的三通道模型,采用变结构控制方法进行控制器设计.结合小扰动原理和Lyapunov稳定性原理进行扰动抑制和稳定性证明,采用梯度算法调整权值进行飞行姿态角控制的消颤处理,采用自适应算法在线调整权值实现PID变结构控制改进.仿真结果表明:采用该算法进行无人机飞行姿态角控制和消颤处理,大幅度提高无人机飞行定姿的精度,横滚角、俯仰角和航向角的控制精度有较大提高,稳定性和收敛性较好,确保了无人机飞行稳定性.     

Performance improvement of aircraft pitch angle control using a new reduced order fractionalized PID controller

In this paper, a new optimal reduced order fractionalized PID (ROFPID) controller based on the Harris Hawks Optimization Algorithm (HHOA) is proposed for aircraft pitch angle control. Statistical tests, analysis of the index of performance, and disturbance rejection, as well as transient and frequency responses, were all used to validate the effectiveness of the proposed approach. The performance of the proposed HHOA-ROFPID and HHOA-ROFPID controllers with Oustaloup and Matsuda approximations was then compared not only to the PID controller tuned by the original HHO algorithm but also to other controllers tuned by cutting-edge meta-heuristic algorithms such as the atom search optimization algorithm (ASOA), Salp Swarm Algorithm (SSA), sine-cosine algorithm (SCA), and Grey wolf optimization algorithm (GOA). Simulation results show that the proposed controller with the Matsuda approximation provides better and more robust performance compared to the proposed controller with the Oustaloup approximation and other existing controllers in terms of percentage overshoot, settling time, rise time, and disturbance rejection.     

一种基于神经网络的数据驱动参数整定法

针对难以建立较准确数学模型的非线性被控对象,提出了一种基于神经网络的数据驱动控制器参数整定法.其设计思想是结合虚拟目标值和神经网络,跳过被控对象,直接得到控制器.此外,利用李亚普诺夫理论证明了神经网络的学习速率在一定范围内可以保证控制器的跟踪误差收敛,并且利用虚拟参考反馈整定(VRFT)算法中的滤波器,结合泰勒展开式,进一步验证了闭环控制系统的稳定性.仿真表明,该方法具有计算负担小,采用数据量少,调节参数方便,强跟踪性等优点.     

产品质量与生产过程的集成控制: 双率采样数据方法

本文在集成控制的框架下研究了工业过程中产品质量和生产过程的实时一体控制问题.首先,基于双速率采样数据提出了产品质量和生产过程的集成控制方案.然后,把控制器设计问题归结为求解一组非线性矩阵不定式,进而提出基于同伦算法的控制器设计方法.最后,通过数值仿真说明所提方法的有效.     

无人机舵偏角的自动检测

针对无人机舵偏角测量方法落后的实际情况,提出了一种利用单片机自动测量无人机舵偏角的方法,并成功研制出无人机舵偏角自动检测仪。实用表明,该无人机舵偏角自动检测仪检测精度高,已经取代了落后的人工测量方法,从而提高了无人机地面检测能力。     

大型风力发电机变桨控制系统设计

变桨距风力发电机已成为风力发电机组的主要研究和发展方向,文章以大型风力发电机组的变桨距系统为研究对象,通过对硬件系统的功能描述,设计了变桨系统的总硬件电路和伺服电路。在此基础上,为实现硬件电路的良好调节作用,对风机启动后变桨程序和调功程序的软件流程图作了详细设计。经过以上的软硬件设计,满足了大型风力发电机组变桨的控制要求。在实际应用中,获得了良好控制效果。     

四旋翼无人机控制系统仿真设计

四旋翼无人机是一种性能优越的垂直起降无人飞行器,能够实现悬停、低速飞行、垂直起降等功能,在军事和民用方面具有重要价值。针对四旋翼无人机的控制系统设计问题,首先分析介绍了四旋翼无人机飞行原理,对其建立动力学模型和运动学模型,然后进行了基于PID控制的控制系统设计,控制系统采用四通道、多闭环的控制结构,包括无人机的姿态控制与轨迹控制。在MATLAB中进行无人机控制系统仿真实现。仿真结果表明,本文所设计的控制系统,能够有效地实现四旋翼无人机的姿态控制、轨迹控制,具有良好的控制精度与响应速度。     

预测-PID串级控制在发酵过程中的应用

本文介绍一种用动态矩阵预测-PID串级控制在抗生素发酵过程中的应用。阐明了系统的控制策略和控制算法。系统具有良好的跟踪性和鲁棒性。     

PWM整流器在内反馈串级调速系统中的应用

本文介绍了几种串级调速系统,将PWM整流器应用在大功率内反馈串级调速系统中。对整流器系统行了建模和分析,运用DSP2812对PWM整流器进行控制,得到动态响应和精度非常优良的系统。     

Model-Free control performance improvement using virtual reference feedback tuning and reinforcement Q-learning

This paper proposes the combination of two model-free controller tuning techniques, namely linear virtual reference feedback tuning (VRFT) and nonlinear state-feedback Q-learning, referred to as a new mixed VRFT-Q learning approach. VRFT is first used to find stabilising feedback controller using input-output experimental data from the process in a model reference tracking setting. Reinforcement Q-learning is next applied in the same setting using input-state experimental data collected under perturbed VRFT to ensure good exploration. The Q-learning controller learned with a batch fitted Q iteration algorithm uses two neural networks, one for the Q-function estimator and one for the controller, respectively. The VRFT-Q learning approach is validated on position control of a two-degrees-of-motion open-loop stable multi input-multi output (MIMO) aerodynamic system (AS). Extensive simulations for the two independent control channels of the MIMO AS show that the Q-learning controllers clearly improve performance over the VRFT controllers.     

ODE–热方程级联系统的事件触发控制

本文针对常微分方程(ODE)耦合偏微分方程(PDE)建模的分布式参数多智能体系统进行研究, 针对一致性同步问题, 提出了事件触发的网络化ODE–热方程级联系统多智能体一致性边界交互协议. 本文考虑的热方程左边界为Neumann边界条件, 并且与ODE系统耦合, 右边界为绝热边界条件. 假设网络化多智能体系统的连接方式为全联通有向拓扑图, 给出ODE–热方程级联系统的多智能体的一致性控制协议. 另外针对现有数字式控制器, 设计了事件触发的一致性控制协议, 并利用李雅普诺夫函数验证了在事件触发条件下ODE–热方程级联系统的稳定性. 最后给出了由5个ODE–热方程级联的多智能体系统的仿真结果, 验证了事件触发控制器的有效性.     

Data-driven predictive control for a class of uncertain control-affine systems

This article studies a data-driven predictive control for a class of control-affine systems which is subject to uncertainty. With the accessibility to finite sample measurements of the uncertain variables, we aim to find controls which are feasible and provide superior performance guarantees with high probability. This results into the formulation of a stochastic optimization problem (P), which is intractable due to the unknown distribution of the uncertainty variables. By developing a distributionally robust optimization framework, we present an equivalent and yet tractable reformulation of (P). Further, we propose an efficient algorithm that provides online suboptimal data-driven solutions and guarantees performance with high probability. To illustrate the effectiveness of the proposed approach, we consider a highway speed-limit control problem. We then develop a set of data-driven speed controls that allow us to prevent traffic congestion with high probability. Finally, we employ the resulting control method on a traffic simulator to illustrate the effectiveness of this approach numerically.     

串联系统的多前馈-反馈广义预测控制

为了充分利用对象的可知信息以实现串联系统的最优控制，提出了串联系统的多前馈-反馈广义预测控制算法，该算法把系统的可知外部扰动作为系统的多输入变量，把可测量的中间变量作为系统的多输出变量，运用多变量广义预测控制的思想给出了算法的控制结构。实现了前馈控制与反馈控制的有机结合，仿真结果表明，该算法能极大地改善串联系统的抗干扰性和鲁棒性。     

快速super twisting 算法及其在飞翼布局无人机姿态控制上的应用

通过在super twisting 算法中增加线性项, 提出一种快速super twisting 算法, 并采用Lyapunov 方法证明了受扰快速super twisting 算法具有比受扰super twisting 算法更优良的收敛特性. 将该算法应用于存在干扰的飞翼布局无人机姿态控制, 设计快速super twisting 观测器以实现对干扰的快速估计和补偿. 仿真结果表明, 在相同的控制器参数下, 相比super twisting 观测器, 快速super twisting 观测器的收敛速度更快, 可提高姿态控制系统的鲁棒性.

     

四旋翼飞行器串级姿态稳定性优化控制研究

针对传统优化控制手段控制四旋翼飞行器能力差这一问题,提出了一种新的稳定性优化控制方法。通过研究动力学原理,分析四旋翼在空气中受到的各种作用力,计算出旋转角速度和旋翼构造平面速度。基于滑流理论、PID控制理论构建出四旋翼飞行器控制模型,分析飞行器的控制原理,阐述了控制系统的工作流程。为检测方法实际工作效果,与传统控制方法进行对比实验,结果可知在相同时间下,受PID方法控制的飞行器运行轨道与预期轨道更加接近,在稳定性和鲁棒性上都强于传统方法。     

无人机地面控制站设计与应用

为了实现无人机系统的飞行操纵、数据链管理和机载任务设备控制,设计了无人机地面控制站;文中介绍了系统基本工作原理和主要功能构成,并对无人机地面控制站的功能要求和技术指标进行了分析,提出了基于基本功能单元的设计准则,以实现系统软硬件的模块化、组合化设计;依据设计原则对地面站的基本功能进行了抽取和设计,并对基本功能单元中的软硬件内容和接口关系进行了详尽的描述;飞行实验表明该设计达到了系统技术指标要求,满足系统对地面控制站的功能性要求。     

Impact time and angle constrained integrated guidance and control with application to salvo attack

In this paper, a novel method is proposed to estimate the impact time (time taken to hit the target) for missiles guided by integrated guidance and control (IGC). Firstly, the elevator deflection command is directly designed in the frame of IGC to make the line‐of‐sight (LOS) angle converge to the desired value in finite time; thereafter, the missiles will fly along the desired LOS until they hit the target. Then a method to estimate the impact time is provided; this can help the user systematically choose the missile parameters in order to achieve a certain impact time, and thus this result can be applied to the case of salvo attack of multiple missiles without online data links. Finally, simulation studies are performed to verify the effectiveness of the proposed scheme.