基于模糊控制的风电机组独立变桨距控制

在额定风速以上时,通常采用变桨距控制技术调节大型风电机组来稳定其输出功率.由于风力发电系统的数学模型具有高度非线性、多变量、强耦合的特点,风速又具有多变性,因此文章在分析传统的PID变桨距控制技术优缺点的基础上,提出了基于三维模糊自适应PID控制的独立变桨距控制技术,并且引入风速的模糊前馈控制技术.对1 MW风电机组进行仿真,结果表明,在额定风速以上时,该方法不仅能稳定风电机组的输出功率,而且可以减小桨叶的拍打振动.     

基于LQR方法的风电机组变桨距控制的动态建模与仿真分析

为了获得更好的变桨距控制效果,将扰动校正LQR(Linear Quadratic Regulator)应用到风电机组变桨距控制中,该方法通过设计扰动状态观测器估计出作为扰动量的风速,在输入量中加入一个反馈量来消除风速产生的扰动影响,然后根据LOR控制理论,计算出状态反馈矩阵.建立了风电机组的动态模型,并根据动态模型在Mat-lab7.1/simulink环境下进行了仿真.仿真结果表明,基于扰动校正的LQR控制方法超调小,变桨距执行机构疲劳度小,具有良好的动态性能.该方法易于工程实现,适用于变桨距控制系统.     

永磁同步风力发电机转速桨距综合功率控制策略研究

控制技术是风力发电机组安全高效运行的关键,文章在分析变速变桨距风力发电机特性的基础上,针对永磁同步风力发电机,提出了一种综合控制策略,研究了变桨距控制和基于转速外环、电流内环的电机侧矢量控制;并且对描述发电机工作过程的风速模型、空气动力学模型、机械传动模型、发电机模型、控制系统模型等进行了研究,基于Matlab/Simulink搭建了模型,对风速变化时机组运行情况进行了仿真,验证了所建模型的合理性及控制策略的正确性。     

风电机组模糊PI控制与前馈控制相结合的变桨控制

针对经典PID变桨距控制器超调量大、波动剧烈等缺陷,提出了一种采用模糊PI控制与前馈控制相结合的控制器来控制浆距角,进而使机组功率稳定在额定功率附近的控制思路。通过对某1.5MW风力发电机组进行仿真,结果表明,该控制器控制效果优于经典PID变桨距控制器。     

风力发电系统权系数独立变桨距矢量控制

风电系统具有多变量、非线性以及不确定等特点,为了减小叶片不平衡载荷造成的机组疲劳和振动,在2 MW风力发电系统中采用了基于权系数的独立变桨距矢量控制。在MATLAB软件中建立机组的数学模型,与统一变桨距系统的控制效果进行比较,通过仿真验证了权系数独立变桨距矢量控制方案的合理性和优越性。     

变速变距风力发电机组整机协调控制策略研究

针对变速变距机组的转矩控制、桨距控制以及整机的协调控制进行了研究.首先,通过模态线性化过程建模被控对象;然后针对机组运行的工作区域进行划分,并研究各区域的主要控制策略,主要针对区域2的PID转矩控制和区域3的桨距控制进行策略阐述,在此基础上,对整机的协调控制策略规则进行阐述;最后进行整机控制的仿真和试验结果分析.     

水平轴潮流能发电机组变桨距系统研究

针对水平轴潮流能发电机组的变桨距系统进行研究.利用理论力学及叶素动量理论对桨叶在机组工作时的受力进行详细分析,提出变桨载荷的理论计算方法.根据潮流能机组轮毂体积小、变桨载荷及凋桨范围大等特点,设计了一种新型的基于电液比例技术的齿轮齿条式变桨距执行机构.该机构结构紧凑、油路新颖、驱动力矩及调桨角度大.在建立系统数学模型的基础上,通过数字仿真对系统的控制特性进行研究.仿真结果表明采用PID控制算法的变桨距系统具有较好的动态特性,能够满足机组功率控制的需求.     

基于单神经元权系数的风电机组独立变桨控制

针对风电机组大型化造成风轮受风剪切效应不良影响的问题,提出了采用模糊PID功率控制器与单神经元动态权系数分配的独立变桨距控制方案。使用Matlab软件对该方案应用于1 MW双馈型风电机组独立变桨距的运行工况进行仿真研究。仿真结果显示,独立变桨距控制方案在保证机组输出功率稳定的前提下,显著改善了风机叶片与风轮承受的轴向不平衡气动力的幅值与波动,进而降低了机组运行过程中受到的气动疲劳载荷,有助于延长机组寿命。     

偏航时风力机组鲁棒控制器的设计

应用鲁棒调节器理论，为偏航时大型变桨距风力机组一个运行于额定风速以上的控制器。领导结果表明，这种鲁棒控制器虽然阶数低，但鲁棒性好，通过调节桨叶的桨距角，能满足控制要求。     

模糊滑模控制技术在风电机组中的应用研究

结合模糊控制和滑模控制的优点,在对变桨距风电机组建模基础上,设计模糊滑模控制器对变桨距系统桨距角进行控制,具有良好的动态和静态特性。     

Identification and monitoring of a PEM electrolyser based on dynamical modelling

To improve the efficiency and the safety of hydrogen electrolysis stations, some technological studies are still under investigation both on methods and materials. As methods, control, monitoring and diagnosis algorithms are relevant tools. This work focuses on the dynamical modelling and the monitoring of Proton Exchange Membrane (PEM) electrolyser. Our contribution consists of three parts: to propose a model of an analytical–dynamical PEM electrolyser, dedicated to control and monitoring; to identify the model parameters and to propose adequate monitoring tools. The proposed model is deduced from physical laws and electrochemical equations and consists of a steady-state electric model coupled with a dynamic thermal model. The estimation of the model parameters is achieved using identification and data fitting techniques based on experimental measurements. Taking into account the information given by the proposed analytical model and the experimentation data (temperature T, voltage U and current I) given by a PEM electrolyser, the model parameters are identified. After estimating the dynamical model, model-based diagnosis is used to monitor the PEM electrolyser and to ensure its safety. We illustrate how our algorithm can detect and isolate faults on actuators, on sensors or on electrolyser system.     

论域自调整模糊PID控制算法设计与仿真

通过建立基于论域调整的自适应模糊PID控制算法对电控直列泵柴油机转速控制的位置环PID参数进行自整定.根据执行器的工作特性建立了执行器模型,与控制算法模型组成闭环进行仿真验证.通过与普通增量式PID控制算法的仿真结果进行比较,结果表明该控制算法在柴油机全工况范围内油量调节齿杆的控制效果优于普通增量式PID控制的效果.     

The thermal and electrical yield of a PV-thermal collector

Four numerical models have been built for the simulation of the thermal yield of a combined PV-thermal collector: a 3D dynamical model and three steady state models that are 3D, 2D and 1D. The models are explained and the results are compared to experimental results. It is found that all models follow the experiments within 5% accuracy. In addition, for the calculation of the daily yield, the simple 1D steady state model performs almost as good as the much more time-consuming 3D dynamical model. On the other hand, the 2D and 3D models are more easily adapted to other configurations and provide more detailed information, as required for a further optimization of the collector. The time-dependent model is required for an accurate prediction of the collector yield if the collector temperature at the end of a measurement differs from its starting temperature.     

Analysis of solar-dehumidification drying

A mathematical model for describing solar-dehumidification drying is presented. Lumped dynamical models have been applied to the moist material and to the solar collector. The other units of the drying system, drying chamber and dehumidifying heatpump were considered to be in a quasi-steady state. The simulation of the weather conditions was carried out by a dynamical weather model. Drying operations under humidistat and temperature control with and without the solar collector were simulated. The analysis of the numerical study shows that although the drying time is not necessarily shorter in the case of solar-dehumidification drying than in that of simple dehumidification drying, the running time of the dehumidifier can be considerably reduced.     

Adaptive Dynamic Inversion for Nonaffine-in-Control Uncertain Systems via Time-Scale Separation. Part II

This paper presents an adaptive dynamic inversion method for uncertain nonaffine-in-control dynamical systems. Online approximation of the adaptive dynamic inversion controller is performed using time-scale separation. The resulting control signal is sought as a solution of a “fast” dynamical equation, which inverts a series-parallel model, whose state is shown to track the state of the original nonaffine-in-control system. The design methodology is constructive, and numerically verifiable sufficient conditions on the system parameters are given. A simulation example, motivated by aerospace applications, illustrates the theoretical results.      

曲轴系统动力学特性的数字化仿真与试验研究

利用ADAMS建立了一种柴油机曲轴系统的刚性体和柔性体的动力学模型，通过仿真测试，得到柴油机的主轴承载荷，活塞侧向力等仿真数据，并针对两种系统分别对其特性进行了比较分析，将计算结果与试验结果进行比较，证明了仿真分析的可靠性，为此类型柴油机的曲轴轴系动力学耦合分析和优化设计提供了依据。     

Improving dynamic performance of proton-exchange membrane fuel cell system using time delay control

Transient behaviour is a key parameter for the vehicular application of proton-exchange membrane (PEM) fuel cell. The goal of this presentation is to construct better control technology to increase the dynamic performance of a PEM fuel cell. The PEM fuel cell model comprises a compressor, an injection pump, a humidifier, a cooler, inlet and outlet manifolds, and a membrane-electrode assembly. The model includes the dynamic states of current, voltage, relative humidity, stoichiometry of air and hydrogen, cathode and anode pressures, cathode and anode mass flow rates, and power. Anode recirculation is also included with the injection pump, as well as anode purging, for preventing anode flooding. A steady-state, isothermal analytical fuel cell model is constructed to analyze the mass transfer and water transportation in the membrane. In order to prevent the starvation of air and flooding in a PEM fuel cell, time delay control is suggested to regulate the optimum stoichiometry of oxygen and hydrogen, even when there are dynamical fluctuations of the required PEM fuel cell power. To prove the dynamical performance improvement of the present method, feed-forward control and Linear Quadratic Gaussian (LQG) control with a state estimator are compared. Matlab/Simulink simulation is performed to validate the proposed methodology to increase the dynamic performance of a PEM fuel cell system.     

Adaptive thermal control for PEMFC systems with guaranteed performance

Proton exchange membrane fuel cell (PEMFC) s are faced with dynamical load scenario in practical applications, and the resulting temperature variation will decrease the performance and consequently shorten the fuel cell lifetime. To address this problem, a control strategy for regulating the stack temperature is proposed in this paper. Firstly, a thermal management-oriented dynamic model of a water-cooled PEMFC system is built to facilitate the control design. Secondly, considering that the stack temperature should be maintained in a certain range regardless of the dynamical changing current demand, a Barrier Lyapunov function is employed to construct a feedback error of the stack temperature. Thirdly, a set of adaptation laws is designed to estimate the unknown parameters related to the gas flow rates in the flow fields. Particularly, a dynamic inversion tracking methodology is applied to design the non-affine input. A Lyapunov method based analysis demonstrates the stability and convergence of the closed-loop properties. Simulation results are provided to show that the proposed control strategy can satisfy all the control objectives and enhance the control performance compared to the proportional-integral controlled case.     

两类实用的单相受热管集总参数动态修正模型

通过惯性补偿的方法,对锅炉单相受热管的两类常用的集总参数模型进行动态修正,得到两类高精度的集总参数动态修正模型;该两类修正模型均能较好地反映热工对象的分布参数特性,既适用于全工况高精度实时仿真培训系统研究,又适用于电站全程控制系统仿真研究。两类修正模型均具有建模简单、计算方便及使用性强特点,有较广泛的工程应用前景。图６参５     

Design and implementation of LQR/LQG strategies for oxygen stoichiometry control in PEM fuel cells based systems

This paper presents the oxygen stoichiometry control problem of proton exchange membrane (PEM) fuel cells and introduces a solution through an optimal control methodology. Based on the study of a non-linear dynamical model of a laboratory PEM fuel cell system and its associated components (air compressor, humidifiers, line heaters, valves, etc.), a control strategy for the oxygen stoichiometry regulation in the cathode line is designed and tested. From a linearised model of the system, an LQR/LQG controller is designed to give a solution to the stated control problem. Experimental results show the effectiveness of the proposed controllers design.