Electro-hydraulic Position Servo Control Research Articles

Optimized PID Controller Based on Beetle Antennae Search Algorithm for Electro-Hydraulic Position Servo Control System.

To improve the controllability of an electro-hydraulic position servo control system while simultaneously enhancing the anti-jamming ability of a PID controller, a compound PID controller that combines the beetle antennae search algorithm with PID strategy was proposed, and used to drive the position servo control system of the electro-hydraulic servo system. A BAS-PID controller was designed, and the beetle antennae search algorithm was used to tune PID parameters so that the disturbance signal of the system was effectively restrained. Initially, the basic mathematical model of the electro-hydraulic position servo control system was established through theoretical analysis. The transfer function model was obtained by identifying system parameters. Then, the PID parameter-tuning problem was converted into a class of three-dimensional parameter optimization problem, and gains of PID controllers were adjusted using the beetle antennae search algorithm. Finally, by comparing the effectiveness of different algorithms, simulation and experimental results revealed that the BAS-PID controller can greatly enhance the performance of the electro-hydraulic position servo control system and inhibit external disturbances when different interference signals are used to test the system’s robustness.

HYBRID ITERATIVE LEARNING CONTROL FOR POSITION TRACKING OF AN ELECTRO HYDRAULIC SERVO SYSTEM

Accurate position control of an electro hydraulic servo system (EHSS) is a challenging task due to inherent system nonlinearities, parametric variations and un-modelled dynamics. Since feedback controllers alone cannot provide perfect tracking control, an integration of feedback and feed forward controller is required. A cascaded iterative learning control (ILC) technique for position control of EHSS is proposed in this paper. ILC is a feed forward controller which modifies the reference signal for a feedback fractional order proportional-integral-derivative (PID) controller by learning through current control input and previous error obtained through trails. Unlike other feed forward controllers, ILC works on signal instead of system which eliminates the need of complete knowledge of the system. As compared to other controllers, the proposed technique provides fast convergence without the need of reconfiguring the existing control loop. Simulation and experiments revealed the effectiveness of the proposed technique for EHSS. The obtained results indicated eight percent improvement in rise time and nearly twenty one percent improvement in the settling time.

Research Progress in Electro-Hydraulic Position Servo Controller

The electro-hydraulic position servo control system is a typical complex nonlinear system. It is difficult in achieving the control which has high quality performance.To overcome the effects of non-linearity, parameter uncertainty, external disturbances and load changes, the design of controller is particularly critical. This paper summarizes the controllers which are applied widely: PID controller, fuzzy controller, neural network controller and hybrid controller. Additionally, the paper analyses their performances. At the same time, this paper also points out the prospects of the controllers.

A compound control strategy combining velocity compensation with ADRC of electro-hydraulic position servo control system

In order to enhance the anti-jamming ability of electro-hydraulic position servo control system at the same time improve the control precision of the system, a compound control strategy that combines velocity compensation with Active Disturbance Rejection Controller (ADRC) is proposed, and the working principle of the compound control strategy is given. ADRC controller is designed, and the extended state observer is used for observing internal parameters uncertainties and external disturbances, so that the disturbances of the system are suppressed effectively. Velocity compensation controller is designed and the compensation model is derived to further improve the positioning accuracy of the system and to achieve the velocity compensation without disturbance. The compound control strategy is verified by the simulation and experiment respectively, and the simulation and experimental results show that the electro-hydraulic position servo control system with ADRC controller can effectively inhibit the external disturbances, the precise positioning control is realized after introducing the velocity compensation controller, and verify that the compound control strategy is effective.

Research on PID Control of Electro-Hydraulic Position Servo Control System Based on SDO Optimization

Abstract. This article introduces the electro-hydraulic position servo control system, establishes its mathematical model and simulates with Simulink, then add PID module, use the empirical method to tune proportional, integral and differential parameters, it is found that adjustment is tedious, and performance improvement is limited. Then use the SDO tools for automatic optimization of PID control parameters, obtained a better simulation results. This tuning method is simple, easy to use, and with good results.

Research of the Electro-hydraulic Servo System Based on RBF Fuzzy Neural Network Controller

This article describes the composition and working principle of electro-hydraulic position servo control system, and establishes a systematic mathematical model. This article presents a controller which is based on Fuzzy neural networks for an electro-hydraulic speed governor. The design process of the RBF Fuzzy neural network control is introduced in detail. This controller which combines the advantages of the Fuzzy control and Neutral networks control can get the best PID parameters by self-adjustment on line. The simulation study proves that this control system has a better adaptability and can improve the control effect greatly.

Modeling and Co-Simulation for Hydraulic System of Test-Bed of Semi-Automatic Coupler Draft Gear Based on AMEsim/Simulink

When the test-bed tests semi-automatic coupler draft gear of the metro vehicle in the case of maximum lateral swinging angle, it requires a hydraulic motor to move the adjustable bearing base which is linked with coupler draft gear in a certain distance until it achieves the desired Angle. In this article, we adopt the valve-control motor electro-hydraulic position servo control system, in which it has the angular measuring device. Besides we optimize the effection of control system by using the fuzzy strategy. Through the AMEsim/Simulink co-simulation and analysis, the level swinging angle of coupler draft gear shows accurate, reliable and stable, which reaches the expected effection completely. With the more and more complex of the controlled object, this kind of intelligent control strategy gives an effective solution for solving complex problems.

A variable structure control with proportional and integral compensations for electrohydraulic position servo control system

Electrohydraulic servomechanisms are widely used in manufacturing machinery, in the heavy-duty machine and automobile industry, because the hydraulic control systems can provide large torque and higher speed of response with fast motion to the plant. However, highly nonlinear and parameter uncertainties mean that the control of the hydraulic system is not always optimum.In this paper, we apply the technique of variable structure control with proportional and integral compensations (PIVSC) to an electrohydraulic position servo control system. The numerical simulation result shows that PIVSC has faster output response than the integral variable structure controller (IVSC) and zero steady-state error with external disturbance to the nonlinear plant.

An optimal variable structure control with integral compensation for electrohydraulic position servo control systems

An approach using variable-structure control with integral compensation is presented for an electrohydraulic position servo control system to achieve accurate servo tracking in the presence of load disturbance and plant parameter variation. Simulations show that the proposed approach may give a rather accurate servo-tracking result and is fairly robust to plant parameter variation and load disturbance. >