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Blade Shape Optimization of Liquid Turbine Flow Sensor

Transactions of Tianjin University 2016年第2期22卷 144-150页

作者：郭素娜张涛孙立军杨振杨文量 School of Electrical Engineering and Automation Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Process Measurement and Control Tianjin 300072 China North China Municipal Engineering Design & Research Institute Tianjin 300384 China

Based on the characteristic curve analysis, the method using D(K^2) square difference of meter factor at different flow rates was developed to evaluate the performance of turbine flow sensor in this study. Then according to the distribution of entrance velocity, it was supposed that reducing the blade area near the tip could decrease the linearity error of a sensor. Therefore, the influence of different blade shape parameters on the performance of the sensor was investigated by combining computational fluid dynamics(CFD)simulation with experimental test. The experimental results showed that, for the liquid turbine flow sensor with a diameter of 10 mm, the linearity error was smallest, and the performance of sensor was optimal when blade shape parameter equaled 0.25.

关键词： turbine flow sensor performance evaluation method parameter optimization mathematical model CFD simulation

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Neural Adaptive control of Microgrid Frequency Regulation with Wind Power

Neural Adaptive Control of Microgrid Frequency Regulation wi...

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Annual Conference of the IEEE Industrial Electronics Society

作者： Weiqiang Liu Chaoxu Mu Ding Wang Chao Luo Chao Ren Tianjin Key Laboratory of Process Measurement and Control Tianjin University Tianjin China School of Automation Southeast University Nanjing China The State Key Laboratory of Management and Control for Complex Systems Chinese Academy of Sciences Beijing China School of Electrical Engineering Wuhan University Wuhan China

Due to the uncertainty of power load demand and the stochastic power generation from renewable energy, frequency fluctuation becomes a major concern of power system, especially for a microgrid. In this paper, an improved proportional-integral (PI) controller based on the neural adaptive control method is proposed to deal with the load frequency control (LFC) problem in a microgrid with wind power. The designed neural adaptive control auxiliary controller is used to provide the adaptive supplement control signal to PI controller in a real-time manner. Simulation studies on a benchmark microgrid system are carried out between the proposed compound controller and traditional PI controller. The simulation results demonstrate the proposed method has a superior performance for stabilizing the frequency over the traditional PI control under disturbances from the load change and wind power.

关键词： Adaptive control Microgrids Frequency control Wind turbines Benchmark testing Power system stability

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Active Disturbance Rejection control in Stribeck Friction Dynamic Compensation for High-accuracy Servo Systems 35

Active Disturbance Rejection Control in Stribeck Friction Dy...

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第35届中国控制会议

作者： WANG Lijun JIAO Ruihua LI Qing YIN Yixin ZHENG Qing School of Automation & Electrical Engineering University of Science and Technology Beijing Key Laboratory of Advanced Control of Iron and Steel Process Ministry of Education Department of Electrical and Computer Engineering Gannon University

ISBN: (纸本)9781509009107

The servo systems are always difficult to design with high-accuracy due to nonlinear stick-slip at the low velocities and the uncertainties of friction dynamic model.A linear active disturbance rejection control(ADRC) dynamic compensation solution is presented independent of the friction *** deal with the problem of observing or tracking for unknown discontinuous signals of friction with Stribeck effect,a kind of linear extended state observer(LESO) algorithm is *** a linear control law is proposed to compensate the friction disturbance *** comparison with proportional-integral-derivative(PID) controller,the simulation results show that the proposed method not only has better accuracy of the discontinuous friction signal tracking,but also ensures better dynamic friction compensation at the low velocities.

关键词： Disturbance rejection Extended state observer Servo systems Stribeck friction Discontinuous tracking

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Effect of carrier gas pressure on vapor condensation and mass flow-rate in sonic nozzle

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Journal of Central South University 2015年第12期22卷 4864-4871页

作者：丁红兵王超陈超 Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and AutomationTianjin University

Non-equilibrium vapor condensation of moist gas through a sonic nozzle is a very complicated phenomenon and is related to the measurement accuracy of sonic nozzle.A gas-liquid two-phase model for the moist gas condensation flow was built and validated by moist nitrogen experiment of homogeneous nucleation through a transonic *** effects of carrier gas pressure on position and status of condensation onset in sonic nozzle were investigated in *** results show that condensation process is not easy to occur at lower carrier pressure and throat *** main factors influencing condensation onset are boundary layer thickness,heat capacity of carrier gas and expansion *** of results can be used to further analyze the effect of condensation on mass flow-rate of sonic nozzle.

关键词： condensation gas-liquid flow droplet growth sonic nozzle carrier gas pressure

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Distributed Consensus for Double Integrator Dynamical Systems without Velocity Information

Distributed Consensus for Double Integrator Dynamical System...

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第35届中国控制会议

作者： Wentao Zhang Zhiqiang Zuo Yijing Wang Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and AutomationTianjin University

ISBN: (纸本)9781509009107

In this paper,the distributed consensus problem for double integrator multi-agent systems is addressed in the light of a novel cooperative law,which relaxes the requirement on the velocity measurements of the agents.A necessary and sufficient condition is derived based on the proposed coordination law under the general directed communication topology via a real-time implementation *** order to save communication burden,we further explicitly explore the cooperation condition where the execution mechanism is event-based and the graph is ***,two examples are depicted to show the feasibility of the designed consensus protocol.

关键词： Double Integrator Multi-agent Systems Consensus Distributed Cooperative Rule Event-triggered control

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Sliding mode tracking control for miniature unmanned helicopters

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Chinese Journal of Aeronautics 2015年第1期28卷 277-284页

作者： Xian Bin Guo Jianchuan Zhang Yao Zhao Bo The Institute of Robotics and Autonomous System Tianjin Key Laboratory of Process Measurement and ControlSchool of Electrical Engineering and Automation Tianjin University

A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter＇s dynamic model is divided into two subsystems,such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles＇ dynamic effects and external disturbances. The global asymptotic stability（GAS） of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportionalintegral-derivative（PID） and linear-quadratic regulator（LQR） cascaded controller in the presence of wind gust disturbances.

关键词： unmanned sliding miniature compensate quadratic cascaded subsystem disturbance facilitate linearized

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A method for contour location of industrial objects based on CNN

A method for contour location of industrial objects based on...

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Youth Academic Annual Conference of Chinese Association of automation (YAC)

作者： Jiangyun Li Qian Zhang School of Automation and Electrical Engineering Key Laboratory of Advanced Control of Iron and Steel Process (Ministry of Education) Beijing China

ISBN: (纸本)9781509044245

There are many industrial fields need to locate the specific texture or contour of the particular objects in the image with complex scenes. Edge detection algorithm based on gray transform is generally hard to handle these issues. This paper presented a model that can accurately locate the specific texture or contour in RGB images with complex scenes by modifying and improving the CNN-based edge detection model HED. It described and practiced the improving method in detail, using accurately locating the outer contour of the plate in images as an example. It achieves the target effectively and accurately and is proved to be a method for only locating the specific texture in images.

关键词： Three-dimensional displays

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Anti-windup compensator synthesis for saturated systems via event-triggered scheme

Anti-windup compensator synthesis for saturated systems via ...

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Chinese control Conference (CCC)

作者： Hongchao Li Zhiqiang Zuo Qingsong Li Yijing Wang Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin Tianjin CN

In this paper, the anti-windup compensator design using event-triggered strategy for linear systems subject to actuator saturation is investigated. Different from the existing result with prescribed anti-windup compensator gain, the main contribution of this paper is that a sufficient condition is presented for anti-windup compensation with event-triggered control and an iterative algorithm is formulated to obtain the anti-windup gain. Moreover, an event-triggering condition involving an exponential term is introduced in order to avoid Zeno behavior when using output feedback control. Numerical example is given to show the validity of the proposed method and the trade-off between the size of the domain of attraction and communication resources saving.

关键词： Actuators Symmetric matrices Output feedback Closed loop systems Optimization Linear systems

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Flow velocity measurement based on ultrasonic cross-correlation technique in oil-water two-phase flow

Flow velocity measurement based on ultrasonic cross-correlat...

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Chinese control Conference (CCC)

作者： Xuewei Shi Xiaoxiao Dong Chao Tan Feng Dong Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin Tianjin CN

ISBN: (纸本)9781509009107

For the velocity measurement of oil-water two-phase flow in horizontal pipeline, a measuring method based on ultrasonic cross-correlation technique is introduced. Two pairs of ultrasonic probes are installed in the upstream and downstream within a certain distance to obtain the flow signal of two-phase flow. The flow velocity is calculated by the cross-correlation method, and the influence of flow patterns and phase distribution are taken into consideration. By combining the cross-correlation algorithm, drift-flux model and kinematic wave theory, the overall superficial velocity measurement model is established. The parameters of this model were calculated in different flow state. The experimental results show that the flow velocity calculated by this model is in good agreement with the actual flow velocity. The relative error is less than ±5%.

关键词： Velocity measurement Oils Pipelines Acoustics Kinematics Fluids Ultrasonic variables measurement

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Analytical Fitting Functions of Finite Sample Discrete Entropies of White Gaussian Noise

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Transactions of Tianjin University 2015年第4期21卷 299-303页

作者：杨正瓴冯勇熊定方陈曦张军 School of Electrical Engineering and Automation Tianjin University Tianjin Key Laboratory of Process Measurement and Control

In order to find the convergence rate of finite sample discrete entropies of a white Gaussian noise(WGN), Brown entropy algorithm is numerically *** the increase of sample size, the curves of these finite sample discrete entropies are asymptotically close to their theoretical *** confidence intervals of the sample Brown entropy are narrower than those of the sample discrete entropy calculated from its differential entropy, which is valid only in the case of a small sample size of WGN. The differences between sample Brown entropies and their theoretical values are fitted by two rational functions exactly, and the revised Brown entropies are more efficient. The application to the prediction of wind speed indicates that the variances of resampled time series increase almost exponentially with the increase of resampling period.

关键词： entropy non-stationary time series prediction white Gaussian noise sample size wind speed

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