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The Society of Instrument and control Engineers Annual Conference 2015

作者： Lijun Wang Fen Zhang Qing Li Yixin Yin Qing Zheng Yumeng Zhang School of Automation & Electrical Engineering University of Science and Technology Beijing Key Laboratory of Advanced Control of Iron and Steel Process (Ministry of Education) University of Science and Technology Beijing Department of Electrical and Computer Engineering Gannon University

Due to the nonlinearities, model uncertainties and disturbances of the two-tank liquid level cascade system,active disturbance rejection controller(ADRC) solution was developed. First, a nonlinear mechanism model and its linearized model were built based on the theories of fluid dynamics for the system. Second, first-order linear ADRCs for the outer loop of the two cascade systems with an unknown order were designed, respectively. With a simple integrator as the normalized type of the feedback system, other parts of dynamic system which are different from the normalized type are treated as the total disturbances. The disturbances were estimated by the second-order linear extended state observer and compensated in the control law. Then the system, with nonlinearities, uncertainties and disturbances, is reduced to only a linear integrator. In comparison with the traditional PI controller, simulation results show that both the proposed ADRCs have better robustness and adaptability against model uncertainties.

关键词： Two-tank systems,nonlinear systems,uncertain systems,cascade systems,active disturbance rejection control

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Online identification of multivariable nonlinear processes with iterative structure learning and application to a diesel engine 19

Online identification of multivariable nonlinear processes w...

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19th IFAC World Congress on International Federation of Automatic control, IFAC 2014

作者： Kowalczyk, Marek Yi, Boliang Isermann, Rolf Institute of Automatic Control and Mechatronics Laboratory of Control Engineering and Process Automation Technical University Darmstadt Germany

ISBN: (纸本)9783902823625

This contribution presents a new methodology for the online identification, which allows the modeling of the stationary and dynamic behavior of nonlinear combustion engines with many input and output variables in short time with an appropriate model structure. The used models are local polynomial model trees. The necessary enhancements and adaptations of the identification algorithm for local polynomial model trees for the online methodology are presented. To enable an online identification, not only the parameters but also the structure of the models has to be adapted to the ongoing measuring procedure at a test bench. This structure adaptation methods use iteratively recorded measured data for the determination of an optimized model partition and regressor selection regarding the quality and complexity of the model. This maximizes the iterative improvement of the mathematical model, leading to a reduced test bench time. The applicability of the developed methodology is shown for the identification of a model from both, an artificial test function as well as a real diesel engine. © IFAC.

关键词： Iterative methods

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Multi-pipeline System Scheduling under Demand Uncertainty

Multi-pipeline System Scheduling under Demand Uncertainty

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第26届中国过程控制会议（CPCC2015）

作者： Wang Jishuai Gu De Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of Sciences State Key Lab.of Industrial Control Technology Institute of Cyber-systems and Control Zhejiang University Key Laboratory of Advanced Process Control for Light Industry (Ministry of Education) Institute of Automation Jiangnan University

In this paper, a discrete mathematical approach to solve scheduling of multi-pipeline systems for petroleum products under demand uncertainty is presented. To deal with the uncertainty, the conditional value-at-risk(CVAR) analysis is adopted as a risk measure. Firstly an improved scheduling approach is proposed to model the multi-pipeline system with the consideration of different pipeline segment sizes. The improved formulation is computationally intractable when pipeline segments have distinct capacities. Then the model takes a scenario-based approach to cope with uncertainty in a CVAR framework. Computational results are presented to demonstrate the effectiveness of the proposed approach. All the instances are implemented using CPLEX.

关键词： Multiproduct pipeline Scheduling MILP formulation Pump

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Measurement and analysis of liquid film velocity in annular flow based on laser-induced fluorescence

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Guangdianzi Jiguang/Journal of Optoelectronics Laser 2015年第3期26卷 523-528页

作者： Xue, Ting Ge, Peng-Hui Yang, Liu-Xiang-Zi Tianjin Key Laboratory of Process Measurement and Control College of Electrical Engineering and Automation Tianjin University Tianjin China

The parameters measurement of liquid film in gas-liquid two-phase annular flow is of great significance for the study of heat and mass transfer and flow characteristics. Laser-induced fluorescence technique based on optical measurement principles to measure film parameters can be simply implemented with high accuracy and without interference of flow fields. Compared with the traditional measurement methods, the method combining the laser-induced fluorescence technique with the cross-correlation technique is developed to measure the liquid film velocity and analyze the flow characteristics. With the aid of digital image processing technology, curves of film thickness at different locations are figured out based on the film images shot by high-speed camera. The flow velocity of the liquid film is accurately measured by processing the images at a fixed interval frame based on the cross-correlation technique. The parabolic fitting technique can be used to estimate the largest correlation coefficient with a higher accuracy and improve the measurement accuracy of film velocity. The experimental results show that the non-intrusive measurement method with a wider range of application can effectively detect the liquid film "break-up" phenomenon and extract the liquid film flow velocity with a higher accuracy. ©, 2015, Board of Optronics Lasers. All right reserved.

关键词： Flow velocity

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A Three-level Batching Strategy for the Planning of Steelmaking-continuous Casting Production

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IFAC-PapersOnLine 2015年第25期48卷 144-149页

作者： Liangliang Sun Fangjun Luan Tianmu Ma Department of Information and Control Engineering Shenyang Jianzhu University Shenyang Liaoning Province China 110004 (Tel: +86(24)23998315 Key Laboratory of Integrated Automation of Process Industry Ministry of Education Northeastern University Shenyang Liaoning Province China 110004 (Tel: +86(24)23998315

This paper focuses on the optimal planning of steelmaking-continuous casting production in real steelmaking plant. The tasks of steelmaking planning are to make the decisions as how to determine the relation between slabs and charges, the sequence of charges in casts and the casting width of slabs while considering the known information about the contract properties, the size properties and processing properties, etc. Effective planning can satisfy the capacity of downstream and continuously casting the steel molten. A three-level batching policy consisting of charge planning, tundish planning, cast planning is proposed in this paper. The different requirement of width in charge planning, tundish planning, cast planning are considered as the performance indicators and constraints equations respectively to formulate the problems. A hybrid optimal strategy combined with the iterated local search (ILS), variable neighborhood search (VNS), and the hybrid optimal strategy with ant colony optimization is adopted. Numerical experiments are done to verify the effectiveness of the three-level batching strategy by using practical data set collected from the steelmaking plant in Baosteel which is one of the most advanced iron and steel enterprises in China. Computational experiments demonstrate that the models and algorithms developed can make an optimal planning in a computationally efficient manner to improve the steel production.

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Hovering control of a Nano Quadrotor Unmanned Aerial Vehicle Using Optical Flow 33

Hovering Control of a Nano Quadrotor Unmanned Aerial Vehicle...

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第三十三届中国控制会议

作者： XIAN Bin LIU Yang ZHANG Xu CAO Meihui Wang Fu The Institute of Robotics and Autonomous System the Tianjin Key Laboratory of Process Measurement and ControlSchool of Electrical Engineering and AutomationTianjin University

ISBN: (纸本)9781479947249

In this paper, a PD controller which uses optical flow to obtain position and velocity feedback is proposed for the autonomous hovering flight control of a nano quadrotor unmanned aerial vehicle(UAV). The nano quadrotor UAV has a mass less than 100 g and is comparatively much smaller than the micro vehicles utilized in previous research. Due to the limited size and payload ability, a wireless camera is employed as the onboard visual device to obtain the position and translational velocity of the UAV. Experiment results are included to demonstrate the good control performance of the proposed design.

关键词： Nano Quadrotor UAV,Optical Flow,Autonomous control

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On control design and tuning for first order plus time delay plants with significant uncertainties

On control design and tuning for first order plus time delay...

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American control Conference

作者： Lijun Wang Qing Li Chaonan Tong Yixin Yin Zhiqiang Gao Qinling Zheng Weicun Zhang School of Automation & Electrical Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Advanced Control of Iron and Steel Process Ministry of Education Beijing 100083 China Center for Advanced Control Technologies Cleveland State University Cleveland OH 44115 USA

ISBN: (纸本)9781479917730

A novel active disturbance rejection control (ADRC) solution and a particular tuning method are presented for a class of time delay system (TDS) with uncertainty. First, the complicated process dynamics is modeled as a simple first order plus large time delay (FOPTD) plant, with the difference between the actual dynamics and its model treated as disturbances to be rejected. Then the reduced order linear extended state observer (RLESO) with input delay is proposed to estimate the time delay state and disturbance. It is shown how the time delay could be eliminated from the characteristic equation of the closed-loop system by manipulations of controller parameters. Secondly, the one parameter tuning (OPT) technique is developed where all controller parameters are made function of a single coefficient. In comparison with optimal proportional-integral-derivative (PID) controller and twice optimum controller (TOC), the simulation results show that the proposed method not only has better accuracy and faster response, but also ensures better robustness and adaptability against uncertain model parameters and external disturbances, especially for the plant with very large time delays.

关键词： tuning design control model parameters process dynamics Characteristic equation one-parameter external disturbance FIRST ORDER controllers Closed loop systems

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Performance evaluation and structure optimization of an inner-outer electrical resistance tomography sensor

Performance evaluation and structure optimization of an inne...

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International Conference on Mechatronics and control, ICMC 2014

作者： Shangjie, Ren Chao, Tan Yanbin, Xu Feng, Dong Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin China

ISBN: (纸本)9781479925384

Electrical resistance tomography is a useful visualization technique to imaging the conductivity distribution inside a closed pipeline from the boundary measurements. Due to its advantages of high speed, low cost and high safety, the technique has been successfully applied in the measurement of many industrial processes. However, since the mathematical model is highly non-linear and ill-posed, the spatial resolution of ERT is low, especially in the center of the objective domain. To overcome the problem, an inner-outer ERT sensor structure was proposed. The structure is consisted by the internal and external electrodes, and can provided more independent measurements for high resolution image reconstruction. To test the performance of the inner-outer sensor structure, six inner-outer ERT sensors are designed, and the influences of the size, number and distribution of the internal electrodes are discussed. After several numerical tests, the inner-outer ERT sensor is proved having the ability of enhancing the spatial resolution of ERT, especially in the area near the internal electrodes. © 2014 IEEE.

关键词： Image reconstruction

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Automatic calibration method of voxel size for cone-beam 3D-CT scanning system

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Chinese Physics C 2014年第4期38卷 69-74页

作者：杨民王晓龙刘义鹏孟凡勇李兴东刘文丽魏东波 School of Mechanical Engineering and Automation Beijing Univ.of Aeronautics and Astronautics Department of Control Science and Engineering Harbin Institute of Technology State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences National Institute of Metrology

For a cone-beam three-dimensional computed tomography （3D-CT） scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes with the movement of the rotary stage along X-ray direction. In order to realize the automatic calibration of the voxel size, a new and easily-implemented method is proposed. According to this method, several projections of a spherical phantom are captured at different imaging positions and the corresponding voxel size values are calculated by non-linear least-square fitting. Through these interpolation values, a linear equation is obtained that reflects the relationship between the voxel size and the rotary stage translation distance from its nominal zero position. Finally, the linear equation is imported into the calibration module of the 3D-CT scanning system. When the rotary stage is moving along X-ray direction, the accurate value of the voxel size is dynamically exported. The experimental results prove that this method meets the requirements of the actual CT scanning system, and has virtues of easy implementation and high accuracy.

关键词： cone-beam CT voxel size least square fitting automatic calibration

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A parallel data acquisition system based on CPCI for ERT 6

A parallel data acquisition system based on CPCI for ERT

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6th World Congress in Industrial process Tomography

作者： Xu, Cong Zhang, Zhiqiang Han, Jun Dong, Feng Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin300072 China

ISBN: (纸本)9780853163220

Electrical resistance tomography (ERT) is to achieve visual detection through boundary sensors array to obtain the realtime distribution of the sensing field. As a nonradiant and unperturbed 2D/3D boundary technique, ERT has wide application prospect in petroleum and chemical industrial processes with conductive continuous phase flow. For obtaining accurate information reflecting the sensing field, many data acquisition systems have been developed for online measurement. To better satisfy industrial requirements, ERT is presently expected to be more flexible, applicable and easier to extend. For this purpose, a system based on industrial bus standard is designed as a 16channel parallel data acquisition system, where FPGA and Compact PCI are adopted as the core components. FPGA is configured with logic control and basic algorithm’s implementation (including digital FIR filter and digital demodulation). Compact PCI, with identical electrical function with PCI but enhanced mechanic structure and hotplugging feature, is employed for highspeed datatransmission. Dedicated software with a userfriendly interface has been developed to configure the signal generator and data *** static experiments using this system have been done, and the results show that the data acquisition system works properly with SNR above 54dB, and the data acquisition rate of this ERT system could reach almost 1400 frames per second without affecting the performance. © 2010, International Society for Industrial process Tomography. All rights reserved.

关键词： Field programmable gate arrays (FPGA)

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