共查询到20条相似文献,搜索用时 31 毫秒
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Alicia Li Jen Keow Amy Mayhall Marzia Cescon Zheng Chen 《International Journal of Hydrogen Energy》2021,46(1):837-851
Metal hydride (MH) hydrogen storage is used in both mobile and stationary applications. MH tanks can connect directly to high-pressure electrolyzers for on-demand charging, saving compression costs. To prevent high hydrogen pressure during charging, hydrogen generation needs to be controlled with consideration for unknown disturbances and time-varying dynamics. This work presents a robust control system to determine the appropriate mass flow rate of hydrogen, which the water electrolyzer should produce, to maintain the gaseous hydrogen pressure in the tank for the hydriding reaction. A control-oriented model is developed for MH hydrogen storage for control system design purposes. A proportional-integral (PI) and an active disturbance rejection control (ADRC) feedback controllers are investigated, and their performance is compared. Simulation results show that both the PI and ADRC controllers can reject both noises from the output measurements and unknown disturbances associated with the heat exchanger. ADRC excels in eliminating disturbances produced by the input mass flow rate, maintaining the pressure of the tank at the charging pressure with little oscillations. Additionally, the parameters estimated by the ADRC's extended state observer was used to predict the state-of-charge (SOC) of the MH. 相似文献
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In this paper, double PWM converter AC excitation system of the variable speed constant frequency doubly fed induction generator (DFIG) for wind power generation is taken as the research object. At present, most vector control systems of rotor-side PWM converter adopt feedforward compensation to realize the purpose of power decoupling control. The decoupling effect is greatly affected by the power changes. A power decoupling control strategy based on auto-disturbance rejection control (ADRC) is proposed. The decoupling control between active power and reactive power is realized by observing the coupling term and the total disturbance of the d-axis and q-axis components of the stator current and the stator voltage with the extended state observer and compensating. Simulation analysis and experimental test show that, on the basis of vector transformation, the rotor-side PWM converter power decoupling control based on ADRC has a small overshoot and fast dynamic response when tracking the change of wind turbine input power, which can achieve the decoupling control between active power and reactive power well. The system has strong robustness and adaptability. 相似文献
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针对漂浮式海上风力机主动结构控制问题,提出一种基于扰动观测的主动滑模控制方法,并应用风力机仿真工具FAST验证所提方法的有效性。在扰动二阶导数有界的前提下,理论证明观测器的稳定性和估计误差的有界性,从而有效估计匹配扰动和非匹配扰动。理论证明一类积分型滑模面的有限时间收敛性和闭环系统稳定性。基于FAST的仿真表明:所提出的主动调谐质量阻尼器(TMD)控制方法与最优被动TMD相比,主动TMD系统的漂浮平台俯仰角度和塔顶位移的均方根值可分别降低11.88%和13.56%,有效提升了风力机承受风浪载荷的能力。 相似文献
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The active disturbance rejection control (ADRC) was proposed by Jingqing Han in the late 1990s, which offers a new and inherently robust controller building block that requires very little information of the plant. Originally, the proposal was based largely on experiments with numerous simulations on various systems of different nature. Later, the effectiveness of the control strategy has also been demonstrated in many engineering applications such as motion control, web tension regulation, and chemical processes. However, many theoretical issues, including its applicability in stabilization, output regulation remain unanswered. In this paper, we consider the nonlinear ADRC for general single input single output nonlinear systems subject to dynamical and external uncertainties. We establish conditions that guarantee the ADRC achieving closed-loop system practical stability, disturbance attenuation, and practical reference tracking. Rigorous proofs are given to show the convergence of the variables. The peaking value reduction and high-frequency noise filtering by combination of the time-varying gain in the initial stage and the constant high gain afterwards are explained by linear ADRC. Illustrative examples are also provided. 相似文献
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针对超临界机组除氧器非线性、大迟延、强耦合和模型时变特性,传统的PID调节器难以使除氧控制系统达到理想的控制效果。为了对除氧器水位和凝泵出口压力的控制取得满意的效果,采用自抗扰控制技术(Auto Disturbance Rejection Control)。通过仿真表明,用ADRC控制器控制除氧系统具有较好的解耦效果、较快的响应速度和较强的抗干扰能力。 相似文献
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Dongdong Zhao Qing Zheng Fei Gao David Bouquain Manfeng Dou Abdellatif Miraoui 《International Journal of Hydrogen Energy》2014
This paper presents a control solution based on dynamic disturbance decoupling control (DDC) for a centrifugal compression system, which is used to supply the compressed air to the fuel cell, thereby reacting with the hydrogen to produce electricity. As a result of its ultra-high speed, this compressor has a great advantage of ultra-compactness, which makes it more suitable for transportation applications. However, unlike positive displacement compressors, the centrifugal compressor has strong coupling between mass flow and pressure, which gives rise to the difficulty of control and also limits its operating region. In this paper, a unique dynamic DDC strategy, based on the active disturbance rejection control (ADRC) framework, is developed to control the mass flow and pressure simultaneously. The experimental results show that, compared with a traditional PI controller this controller performs better in both the transient and steady states. This control system has been validated on a 10 kW fuel cell model under load variations. 相似文献
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《Journal of power sources》2004,128(2):218-230
In this paper, the integration of a fuel cell into the power system is treated as a load frequency control (LFC) problem with the fuel cell acting as a load disturbance source. The integration of a fuel cell into the power system results into a change in real power. But changes in real power affect the system frequency. Thus, the integration will result into a change of frequency of the synchronous machines. Hence, we need to design a control scheme for keeping the system in the steady state. An optimal controller based on the disturbance accommodation control (DAC) theory is proposed for this load frequency control problem. For demonstrating the effectiveness of the proposed controller, we have considered a two-area power system with the fuel cell introduced in area 1. The fuel cell is considered as an external disturbance to each subsystem. A mathematical model is derived for each subsystem and based upon these models controllers are designed for keeping each subsystem stable, which in turn stabilizes the overall system. So, the proposed controller is decentralized in nature. To account for the modeling uncertainties, an observer is designed to estimate each subsystem’s own and interfacing variables. The controller uses these estimates to optimize a given performance index and allocate generating unit outputs according to the requirements. 相似文献
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针对火电厂选择性催化还原(Selective Catalytic Reduction,SCR)烟气脱硝系统机理复杂,工况变化时呈现的不确定性、强扰动等特点,提出了一种基于互信息和PID神经网络的SCR烟气脱硝扰动补偿控制方法。利用PID前向神经网络的学习性能逼近被控对象的逆构成扰动观测器对系统进行反馈补偿,以达到超前消除系统扰动的目的。选取观测扰动和系统扰动的互信息为目标函数,采用改进的帝国竞争算法实现PID神经网络权值的优化调整。设计鲁棒PID控制器来进一步克服被控对象存在的不确定性。仿真实验表明,该方法具有突出的抗干扰能力和较好的鲁棒性,控制品质优于常规的PID控制。 相似文献
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Bao-Zhu Guo Hua-Cheng Zhou A. S. AL-Fhaid Arshad Mahmood M. Younas Asim Asiri 《Journal of Dynamical and Control Systems》2014,20(4):539-558
We consider boundary stabilization for a one-dimensional Euler-Bernoulli equation with boundary moment control and disturbance. The active disturbance rejection control (ADRC) and sliding mode control (SMC) approaches are adopted in investigation. By the ADRC approach, a state feedback disturbance estimator with time-varying gain is designed to estimate the disturbance. It is shown that the closed-loop system is asymptotically stable by canceling the disturbance in the feedback loop with its online estimation. In the second part, the SMC is applied to reject the disturbance. The well-posedness of the closed-loop system via SMC is proven, and the monotonicity of the “reaching condition” is presented without differentiating the sliding mode function which may not always exist for the weak solution. The numerical experiments are presented to illustrate the convergence and the peaking value reduction caused by the constant high gain. In addition, the control energies are compared numerically for two approaches. 相似文献
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风电机组模型的不确定性以及风等外部干扰严重影响风电机组输出功率的稳定性,因此,将自抗扰控制器(ADRC)引入到风电机组变桨距控制中。当风速高于额定风速时,通过自抗扰变桨距控制策略有效调节桨距角,保证风电机组输出功率的稳定性。但ADRC参数繁多,仅靠专家经验进行整定比较困难。因此,文章提出将改进灰狼优化算法应用到ADRC中,完成参数的自寻优整定过程。仿真结果证明,经改进灰狼优化算法进行参数整定后的变桨距自抗扰控制系统能够对桨距角进行精确调整,并将输出功率快速稳定到额定值附近,具有较快的响应速度以及较好的抗扰动能力。 相似文献
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Disturbance accommodating control (DAC) has been developed in the last decades for wind turbines to control the rotor/generator speed and to reduce structural loads. The method allows accommodating unknown disturbance effects by using the combination of disturbance observers and disturbance rejection controllers. The actual main problem of DAC is to define suitable disturbance observer and controller gain matrices to achieve the desired overall performance including turbine speed regulation in combination with structural load mitigation. The disturbance rejection controller is often designed and tuned separately for individual applications and operating conditions. The closed-loop system stability and uncertainties due to the use of the linearized reduced-order model in controller synthesis procedure are not fully considered. This paper introduces a method to design DAC by optimizing the observer and controller parameters simultaneously to guarantee system performance respecting to structural loads mitigation, power regulation, and robustness. To eliminate the rotor speed control steady-state error due to model uncertainties, partial integral action is included. Simulation results using NREL reference wind turbine models show that the proposed method successfully regulates the rotor speed without error despite the presence of the model uncertainties. Structural loads are also reduced using proposed method compared to DAC designed by Kronecker product method. The proposed approach is able to define a stable and robust DAC controller by solving a non-smooth H∞ optimization problem with structure and stability constraints. 相似文献
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Output power of wind turbine generator (WTG) is not constant and fluctuates due to wind speed changes. To reduce the adverse effects of the power system introducing WTGs, there are several published reports on output power control of WTGs detailing various researches based on pitch angle control, variable speed wind turbines, energy storage systems, and so on. In this context, this paper presents an integrated control method for a WF to reduce frequency deviations in a small power system. In this study, the WF achieves the frequency control with two control schemes: load estimation and short-term ahead wind speed prediction. For load estimation in the small power system, a minimal-order observer is used as disturbance observer. The estimated load is utilized to determine the output power command of the WF. To regulate the output power command of the WF according to wind speed changing, short-term ahead wind speed is predicted by using least-squares method. The predicted wind speed adjusts the output power command of the WF as a multiplying factor with fuzzy reasoning. By means of the proposed method, the WF can operate according to the wind and load conditions. In the WF system, each output power of the WTGs is controlled by regulating each pitch angle. For increasing acquisition power of the WF, a dispatch control method also is proposed. In the pitch angle control system of each WTG, generalized predictive control (GPC) is applied to enhance the control performance. Effectiveness of the proposed method is verified by the numerical simulations. 相似文献
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《International Journal of Hydrogen Energy》2020,45(54):29705-29717
This paper proposes a novel observer-based nonlinear triple-step controller for the air supply system of polymer electrolyte membrane (PEM) fuel cell. The control objective is adjusting the oxygen excess ratio to its reference value under fast current transitions, so as to avoid the oxygen starvation and obtain the maximum net power. Considering that the cathode pressure cannot be measured directly, we design a disturbance observer to estimate the cathode pressure based on the developed third-order nonlinear model of air supply system. Next, a triple-step nonlinear method is applied to derive an oxygen excess ratio tracking controller, wherein the stability of closed-loop system is guaranteed by Lyapunov-based technique. Subsequently, several key issues of controller in practical implementation are explained, and then the robustness analysis against the considered lumped disturbance is carried out. Finally, the performance of the proposed control scheme is validated through a series of comparative simulations, and the simulation results demonstrate the effectiveness and robustness of the proposed approach under different load variations and parameter uncertainties. 相似文献
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《International Journal of Hydrogen Energy》2022,47(67):29148-29161
This paper proposes an actuator fault detection observer design method for a proton exchange membrane fuel cell (PEMFC) system described by delta operator form. In the first, a nonlinear mathematical model for the PEMFC system is proposed by using the mechanism analysis method, which includes the time delay, external disturbance and uncertainty to reduce the conservatism of the design. Then, in order to detect the actuator fault, the functional observer is constructed as the residual generator, and sufficient conditions for the stability of the error system are obtained by using the Lyapunov-krasovsky functional theory in terms of linear matrix inequalities (LMIs), so as to ensure the design of the required functional observer. Finally, simulation results are provided to show the effectiveness of the approach. 相似文献