Semi-Active Direct Velocity Control Method of Dynamic Response of Spatial Reticulated Structures Based on MR Dampers

In this paper, a semi-active optimal control strategy for spatial reticulated structures (SRS) with MR dampers subjected to dynamic actions was proposed. The motion equation of SRS embedded with MR dampers was set up. The performance function of the optimal control strategy including both the structural responses and the control efforts was constituted for the optimization of feedback gain and MR damper placement in SRS, and an integrated method of genetic-gradient based algorithm was developed to solve this optimization problem. The clipped-optimal semi-active control strategy in the conjunction of velocity output feedback was applied to compute the desired control force from the MR dampers. Finally, a numerical example of SRS dealing with optimal placement of MR dampers and feedback gains of control system demonstrates the validity of the present semi-active optimal control strategy.

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Suppression of Vibrations Induced by Fluctuating Wind for Long-Span Cable-Stayed Bridge Using MR Dampers

10.20855/ijav.2019.24.21191 ◽

2019 ◽

Vol 24 (2) ◽

pp. 262-270

Author(s):

Zhao-Dong Xu ◽

Meng Xu ◽

Da-Huan Jia

Keyword(s):

Optimal Control ◽

Control Strategy ◽

State Control ◽

Optimal Control Strategy ◽

Box Girder ◽

Mr Dampers ◽

Cable Stayed Bridge ◽

Long Span ◽

Wind Induced Vibration ◽

Fluctuating Wind

Cable-stayed bridges subjected to wind excitations will cause intense vibration due to their high flexibility in characteristic. Employment of magnetorheological (MR) dampers to realize the vibration smart-control of cablestayed bridges has become a considerable research topic in recent decades. In this paper, the plane truss finite element model (FEM) of a cable-stayed bridge with MR dampers is established. Fluctuating wind field is generated using the weighted amplitude wave superposition (WAWS) method and Kaimal spectrum, and then the time-history sample curve of wind speed is obtained. Fluctuating wind-induced vibration of the long-span cable-stayed bridge installed with MR dampers is analyzed by linear quadratic regulator (LQR) classical optimal control strategy and LQR tri-state control strategy. After the optimal control force is calculated by LQR classical optimal control strategy, control parameters and the input currents of MR dampers can be determined according to the windinduced vibration by LQR tri-state control. Results show that longitudinal and vertical wind-induced vibration responses of the box girder of the cable-stayed bridge are reduced obviously when MR dampers are arranged between the box girder and pylons.

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Simulation and Optimal Control of AMT Starting-up Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.672 ◽

2013 ◽

Vol 380-384 ◽

pp. 672-675

Author(s):

Li Na Ren ◽

Na Na Tang ◽

Han Qi Yue ◽

Bing Zhao Gao

Keyword(s):

Optimal Control ◽

Simulation Model ◽

Control Strategy ◽

Pid Control ◽

Manual Transmission ◽

Optimal Control Strategy ◽

Automated Manual Transmission ◽

Starting Process ◽

Set Up ◽

Experimental Values

For a vehicle with 5-speed AMT (Automated Manual Transmission), AMESim model of the powertrain is set up, and comparison of simulation and experimental values is carried out to test the reliability of the simulation model. Through the co-simulation of AMESim and Simulink, we use optimal control and PID control respectively to control the starting process. The simulation result indicates that the optimal control strategy can satisfy the requirement for the drivability and smoothness.

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A PID control method based on optimal control strategy

Numerical Algebra Control & Optimization ◽

10.3934/naco.2020019 ◽

2019 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

Hong Niu ◽

◽

Zhijiang Feng ◽

Qijin Xiao ◽

Yajun Zhang ◽

...

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Pid Control ◽

Control Method ◽

Optimal Control Strategy

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Design of Control Strategy and Effect Evaluation for Primary Frequency Regulation of Wind Storage System

Frontiers in Energy Research ◽

10.3389/fenrg.2021.739439 ◽

2021 ◽

Vol 9 ◽

Author(s):

Cuiping Li ◽

Zheshen Zhang ◽

Junhui Li ◽

Yunbao Ma ◽

Jiajun Zou

Keyword(s):

Optimal Control ◽

Power System ◽

Control Strategy ◽

Evaluation Method ◽

Control Method ◽

Storage System ◽

Frequency Regulation ◽

Optimal Control Strategy ◽

Performance Evaluation Method ◽

Primary Frequency

Because of wind sources’ volatility and intermittent news, wind power has made a more and more heavy burden on the power system. This paper analyzes in detail the traditional control method, parallel control strategy and serial control strategy of the wind storage system, and combines the advantages of the two to propose an optimal control strategy. A comprehensive performance evaluation method for the primary frequency regulation of the ESS participating in the power grid is proposed based on the power system operation requirements. In the example, the frequency modulation performance of the optimal control strategy is verified by the evaluation method described in this paper in the Chinese frequency adjustment market.

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Feedforward-Feedback Control of Offshore Platforms Excited by Random Wave

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 1, Parts A and B ◽

10.1115/omae2005-67246 ◽

2005 ◽

Cited By ~ 1

Author(s):

Chunyan Ji ◽

Qingmin Meng

Keyword(s):

Optimal Control ◽

White Noise ◽

Control Strategy ◽

Control Method ◽

Structural Information ◽

External Loading ◽

Random Wave ◽

Offshore Platforms ◽

Control Force ◽

Analog Filter

Conventional optimal control theories usually deal with optimal control force that involves only structural information. In order to control the excessive vibrations of offshore platforms more effectively, this paper presents a control strategy, which employs both information of the controlled system and external loading, namely feedforward-feedback (FF-FB) control strategy. FF-FB control strategy requires that the input signal be a process of white noise for obtaining the optimal control result. So, an analog filter is designed in this paper to approximately represent the random wave force by a process of white noise. In order to investigate the feasibility and effectiveness of the proposed method, a numerical example applied to an offshore platform is presented in this paper. The numerical results demonstrate that the proposed method offers advantage in performance over the control method employing only state feedback.

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A semi-active stochastic optimal control strategy for nonlinear structural systems with MR dampers

Smart Structures and Systems ◽

10.12989/sss.2009.5.1.069 ◽

2009 ◽

Vol 5 (1) ◽

pp. 69-79 ◽

Cited By ~ 13

Author(s):

Z.G. Ying ◽

Y.Q. Ni ◽

J.M. Ko

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Stochastic Optimal Control ◽

Structural Systems ◽

Optimal Control Strategy ◽

Mr Dampers ◽

Nonlinear Structural

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Speed Control of PMSM Based on an Optimized ADRC Controller

Mathematical Problems in Engineering ◽

10.1155/2019/1074702 ◽

2019 ◽

Vol 2019 ◽

pp. 1-18 ◽

Cited By ~ 1

Author(s):

YiBo Meng ◽

BingYou Liu ◽

LiChao Wang

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Disturbance Rejection ◽

Control Method ◽

Nonlinear Function ◽

Active Disturbance Rejection Control ◽

Optimal Control Strategy ◽

External Interference ◽

Active Disturbance Rejection ◽

Disturbance Rejection Control

Permanent-magnet synchronous motor (PMSM) is a nonlinear, multivariate, strongly coupled system with uncertain external interference. A general control method cannot meet system requirements. This study proposes an optimal control strategy based on active disturbance rejection control (ADRC) to achieve high-precision control of PMSM. First, interpolation fitting is used to construct a nonlinear function with improved continuity and derivative near the origin and segment points. Second, various components of active disturbance rejection control are constructed based on the new nonlinear function, which mainly improves the extended state observer and nonlinear state error feedback. Simulation results show that under similar parameters, the improved active disturbance rejection control has smaller overshoot, faster tracking capacity, and stronger anti-interference capability compared with traditional active disturbance rejection control. Finally, the optimized active disturbance rejection control is used in the motion control system of PMSM. Experimental results show that the proposed optimal control strategy is simple and has good control performance.

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Stochastic Control for Intra-Region Probability Maximization of Multi-Machine Power Systems Based on the Quasi-Generalized Hamiltonian Theory

Energies ◽

10.3390/en13010167 ◽

2019 ◽

Vol 13 (1) ◽

pp. 167

Author(s):

Xue Lin ◽

Lixia Sun ◽

Ping Ju ◽

Hongyu Li

Keyword(s):

Optimal Control ◽

Power Systems ◽

Control Strategy ◽

Stochastic Systems ◽

Control Method ◽

Dynamic Programming Method ◽

Stochastic Disturbances ◽

Optimal Control Strategy ◽

Systems Model ◽

The Impact

With the penetration of renewable generation, electric vehicles and other random factors in power systems, the stochastic disturbances are increasing significantly, which are necessary to be handled for guarantying the security of systems. A novel stochastic optimal control strategy is proposed in this paper to reduce the impact of such stochastic continuous disturbances on power systems. The proposed method is effective in solving the problems caused by the stochastic continuous disturbances and has two significant advantages. First, a simplified and effective solution is proposed to analyze the system influenced by the stochastic disturbances. Second, a novel optimal control strategy is proposed in this paper to effectively reduce the impact of stochastic continuous disturbances. To be specific, a novel excitation controlled power systems model with stochastic disturbances is built in the quasi-generalized Hamiltonian form, which is further simplified into a lower-dimension model through the stochastic averaging method. Based on this Itô equation, a novel optimal control strategy to achieve the intra-region probability maximization is established for power systems by using the dynamic programming method. Finally, the intra-region probability increases in controlled systems, which confirms the effectiveness of the proposed control strategy. The proposed control method has advantages on controlling the fluctuation of system state variables within a desired region under the influence of stochastic disturbances, which means improving the security of stochastic systems. With more stochasticity in the future, the proposed control method based on the stochastic theory will play a novel way to relieve the impact of stochastic disturbances.

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