Robust Suboptimal Control of an Electro-Hydraulic System with Variable Supply Pressure

2012 ◽  
Vol 215-216 ◽  
pp. 1283-1290
Author(s):  
Min Zhang ◽  
Jin Wang ◽  
Guo Bing Huang
Keyword(s):  
Hydraulic System ◽  
Closed Loop ◽  
Control Method ◽  
Performance Criterion ◽  
Suboptimal Control ◽  
Parameter Uncertainties ◽  
Genetic Search ◽  
Supply Pressure ◽  
Loop Transfer Function ◽  
Quadratic Performance

In this study, a robust H2 suboptimal control method is proposed for an electro-hydraulic system with variable supply pressure. The H2 suboptimal controller is designed to minimize the sum of a quadratic performance criterion and the H2 norm of the closed-loop transfer function from the white noise disturbance to the system state space variables. The genetic algorithm is used to select the weighting matrices of the quadratic performance criterion. In order to improve the robust performance, parameter uncertainties of the electro-hydraulic system are considered in the process of genetic search. Simulation results demonstrate the effectiveness of the proposed approach.

Research into the Variable Speed Pump Control System for Driving the Cutter Head of Shield Tunneling Machine

2009 ◽  
Vol 628-629 ◽  
pp. 257-262 ◽  
Author(s):  
Tong Xing
Keyword(s):  
Control System ◽  
Hydraulic System ◽  
Closed Loop ◽  
Control Method ◽  
Control Technique ◽  
Closed Loop Control ◽  
Variable Speed ◽  
Shield Tunneling ◽  
Loop Control ◽  
Cutter Head

The cutter head drive hydraulic system of φ1.8m simulate shield machine is introduced in this article, which has the variable speed pump control technique and the closed loop control method. The AMESim simulation model of the hydraulic system is built up, and the efficiency of the hydraulic system, speed control performance by open loop and closed loop control are analyzed. The result of the simulation shows that the variable speed pump control system has higher efficiency than the variable displacement pump control system about 4%-26% in the same condition when the cutter head speed is at the range of 0.5-4r/min, and the hydraulic system has good dynamic characteristics in closed-loop PID control.

A Control Algorithm for Active/Passive Hydraulic Winches Used in Active Heave Compensation

2019 ◽  
Author(s):  
Geir-Arne Moslått ◽  
Damiano Padovani ◽  
Michael R. Hansen
Keyword(s):  
Hydraulic System ◽  
Control Algorithm ◽  
Closed Loop ◽  
Peak Pressure ◽  
Control Method ◽  
High Fidelity Simulation ◽  
Speed Performance ◽  
Variable Displacement ◽  
Active Motor ◽  
Classical Control

Abstract The most common active heave compensated offshore cranes have hydraulic winch systems. This paper investigates an active/passive hydraulic winch system with variable-displacement motors and variable-displacement pumps. The paper addresses the challenges when the active motors are set with a low displacement. The active motor displacement is shown to have significant impact on the dynamics of the closed loop hydraulic system. The classical control strategy for this type of system do not address these challenges and will in certain situations have significantly reduced performance. Therefor, a new control method is presented that utilize the variable displacement of the pumps and motors for speed control and to improve dynamics characteristics. The new winch controller is tested in a high-fidelity simulation model and is shown to improve low speed performance, reduce winch speed limitations by up to 30%, reduce system peak pressure by approximately 20%, and reduce control error by approximately 30%.

Research on the Startup Control for the Closed-Circuit Hydraulic System Based on Expert Control Method

2007 ◽  
Author(s):  
Dongming Hu ◽  
Bing Xu ◽  
Huayong Yang
Keyword(s):  
Hydraulic System ◽  
Closed Loop ◽  
Control Method ◽  
Static Friction ◽  
Work Conditions ◽  
Friction Model ◽  
Closed Circuit ◽  
Expert Control ◽  
Working Principle ◽  
Startup Performance

The closed circuit hydraulic system is a typical nonlinear and time-varying system. In order to get excellent startup performance, the controller based on expert control method was designed. The theoretical and experimental research of the controller was carried out. Firstly, the working principle of the closed circuit hydraulic system was introduced. The difficulties of pressure pre-balanced control and closed-loop speed control for the system starting were indicated because of its friction, high-inertia and time delay. The influence of nonlinear friction on the startup performance of the system was analyzed. And the initial model of the friction was established through experiments. Then, the intelligent controller was designed basing on expert control method. The startup performance was evaluated by the integral of difference between the desired and the practical speed while the system ran. The static friction model and the parameters of the controller can be modified by the expert controller according to the last two results. Finally, experiments were carried out under different work conditions, namely variable loads and oil-temperatures. The results show that the startup performance of the system is excellent. The robustness of the expert controller is strong under different work conditions. That is, the proposed method is robust in the presence of nonlinearities and uncertainties.

scholarly journals Angle Displacement Robust Controller for the Port Plate of the Hydraulic Transformer

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Wei Shen ◽  
Jihai Jiang ◽  
Xiaoyu Su ◽  
Hamid Reza Karimi
Keyword(s):  
Hydraulic System ◽  
Control Method ◽  
Design Method ◽  
Critical Issue ◽  
Friction Torque ◽  
Cylinder Block ◽  
Parameter Uncertainties ◽  
Robust Controller ◽  
Hydraulic Transformer ◽  
Guaranteed Cost

The hydraulic transformer is used in the hydraulic system to enhance the efficiency. However, how to control the angle displacement of the port plate is becoming a critical issue because of the new structure of the hydraulic transformer. This paper presents a new method for the angle displacement control system. Firstly, the basic principle of the system is presented. Then, the disturbance which is mainly the friction torque between the port plate and the cylinder block is calculated to estimate the range. Furthermore, the guaranteed cost control (GCC) is analyzed and combined with the disturbance and the characteristics of parameter uncertainties. Finally, the proposed control method is compared with the traditional PI control and the simulation result shows the effectiveness of the proposed design method.

State Feedback Robust H∞ Control for Generalized Discrete System and Simulation

2013 ◽  
Vol 467 ◽  
pp. 621-626
Author(s):  
Chen Fang ◽  
Jiang Hong Shi ◽  
Kun Yu Li ◽  
Zheng Wang
Keyword(s):  
Discrete System ◽  
State Feedback ◽  
Closed Loop ◽  
The State ◽  
Linear Matrix ◽  
Sufficient Condition ◽  
Matrix Inequalities ◽  
Parameter Uncertainties ◽  
Robust Controller ◽  
Closed Loop Systems

For a class of uncertain generalized discrete linear system with norm-bounded parameter uncertainties, the state feedback robust control problem is studied. One sufficient condition for the solvability of the problem and the state feedback robust controller are obtained in terms of linear matrix inequalities. The designed controller guarantees that the closed-loop systems is regular, causal, stable and satisfies a prescribed norm bounded constraint for all admissible uncertain parameters under some conditions. The result of the normal discrete system can be regarded as a particular form of our conclusion. A simulation example is given to demonstrate the effectiveness of the proposed method.

An Expert Controller Based on Transient Response Patterns

2011 ◽  
Vol 219-220 ◽  
pp. 3-7
Author(s):  
Ning Zhang ◽  
Rong Hua Liu
Keyword(s):  
Control System ◽  
Transient Response ◽  
Closed Loop ◽  
Performance Criterion ◽  
Response Patterns ◽  
Loop Control ◽  
Expert Control ◽  
Closed Loop Control System ◽  
Loop Control System ◽  
Control Decision

An expert control system based on transient response patterns and expert system techniques is proposed in this paper. Depending on the features of the closed-loop control system determines the control decision and adjusts the parameters of the controller. The proposed method requires minimal proper information about the controlled plant and, with the linear re-excitation learning method, the system is kept satisfying the performance criterion.

Analysis of Reset Control Systems Consisting of a FORE and Second-Order Loop1

2001 ◽  
Vol 123 (2) ◽  
pp. 279-283 ◽  
Author(s):  
Qian Chen ◽  
Yossi Chait ◽  
C. V. Hollot
Keyword(s):  
Control Systems ◽  
Closed Loop ◽  
Second Order ◽  
Step Response ◽  
Steady State Response ◽  
First Order ◽  
State Response ◽  
Loop Transfer Function ◽  
Performance Specifications ◽  
Reset Control

Reset controllers consist of two parts—a linear compensator and a reset element. The linear compensator is designed, in the usual ways, to meet all closed-loop performance specifications while relaxing the overshoot constraint. Then, the reset element is chosen to meet this remaining step-response specification. In this paper, we consider the case when such linear compensation results in a second-order (loop) transfer function and where a first-order reset element (FORE) is employed. We analyze the closed-loop reset control system addressing performance issues such as stability, steady-state response, and transient performance.

Synchronous Control Characteristics Analysis of Shield Propulsion Hydraulic System Based on Tracking Differentiator and Self-Adaptive Nonlinear PID

2021 ◽  
Author(s):  
Sen Li ◽  
XiaoHua Cao
Keyword(s):  
Pid Control ◽  
Hydraulic System ◽  
Control Method ◽  
Hydraulic Systems ◽  
Fuzzy Pid Control ◽  
Synchronous Control ◽  
Tracking Differentiator ◽  
Characteristics Analysis ◽  
Servo Tracking ◽  
Self Adaptive

Aiming at the low precision problem of multi-cylinder cooperative propulsion control in different regions of shield propulsion hydraulic systems under conditions of large load changes, this paper proposes a tracking differentiator and self-adaptive nonlinear PID (TD-NPID) control method to improve the synchronous control characteristics of shield propulsion hydraulic systems. First, the working principles of shield propulsion hydraulic systems were analyzed, and a mathematical model and TD-NPID controller were developed. Then, a simulation model was developed in AMESim-MATLAB environment, and the synchronous dynamic performances of fuzzy PID control, conventional PID control, and TD-NPID control were compared and analyzed. The results demonstrated that the shield propulsion hydraulic system with TD-NPID control had better servo tracking ability and steady-state performance than the systems with fuzzy or conventional PID control, which verified the feasibility of the application of TD-NPID control for the synchronous control of shield propulsion hydraulic systems.

scholarly journals The Adaptive Neural Control for a Class of High-Order Uncertain Stochastic Nonlinear Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Xiaoyan Qin
Keyword(s):  
Nonlinear Systems ◽  
Neural Control ◽  
Closed Loop ◽  
Control Method ◽  
High Order ◽  
Stochastic Nonlinear Systems ◽  
Closed Loop System ◽  
Adaptive Neural Control ◽  
Control Scheme ◽  
Approximation Capability

This paper studies the problem of the adaptive neural control for a class of high-order uncertain stochastic nonlinear systems. By using some techniques such as the backstepping recursive technique, Young’s inequality, and approximation capability, a novel adaptive neural control scheme is constructed. The proposed control method can guarantee that the signals of the closed-loop system are bounded in probability, and only one parameter needs to be updated online. One example is given to show the effectiveness of the proposed control method.

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