Proportional Control Valve Research Articles

Design of a New Type of Vehicle Braking Energy Recycling Device

According to the vehicle energy conservation and emissions reduction, it is applied the integrated technology of machinery, single chip microcomputer and hydraulic transmission to design mechatronics device which can be used for urban transit vehicle braking energy recovery. Using hydraulic accumulator as the energy storage and release components, based on embedded microcomputer control technology and electro-hydraulic proportional valve control technology, using sensors to collect vehicle operation condition parameters, through single chip microcomputer intelligent control to make the vehicle has the function of adaptive recovery and release energy when braking and start. The application of this device, with energy conservation and emissions reduction, has the effect of reducing vehicle emissions.

Performance Analysis of Directional Control Valve: An Overview

Directional control valves start, stop or change the direction of flow in compressed air applications. To understand the different applications of compressed air and how valves are used, one must first have knowledge of the kinds and types of valves used by industries. This paper studies local valve control of the electro-hydraulic system. The slow response of hydraulic control valve usually becomes the hold-up of whole system performance. Although fast valves (e.g. high-bandwidth servo-valves) are available, they are far more expensive than slow valves (e.g. proportional directional control valves). To improve the performance of proportional directional control valves, three different types of controllers are synthesized. Firstly, based on the pole zero cancellation technique, an open loop compensator is designed which requires the accurate valve dynamic model information; Secondly, a full state feedback adaptive robust controller (ARC) is synthesized, which effectively takes into account the effect of parametric uncertainties and uncertain nonlinearities such as friction force and flow force. Finally, an output feedback ARC controller is synthesized to address the problem of un measurable states. Keywords: valve, hydraulic device, Simulink.

3방 비례제어 조절밸브 개발 및 성능 연구

Abstract Korea District heating corp. recently give an attention to combine the district heating and supply pipes as a two pipe system that are in the present system separated with room heating and warm water supply pipe, and the two pipesystem is commonly applied for heating service in European countries. In the new two pipe system, only one heat sourceis supplied to a house and partitioned into room heating and warm water supply by household substation. So the effectivedistribution of supplied heat source in accordance to user intention is very important. This paper presents the developmentand performance test of three-way proportional control valve for a combined heat source system in district heating. Theproposed valve is controlled to partition heat source into two different directions ： hot water distributor for space heatingand household substation for warm water supply in response to the pressure drops of tap water caused by the user. The performance investigation is shown within 3% of error compared to the theoretical model of the three-way proportionalvalve and its controllability is verified.

Hydraulic Leveling Technology for Electro-Hydraulic Proportional Control Based on Fuzzy PID

In modern military and civil technologies, platforms with equipment on them are often needed to be adjusted to horizontal position rapidly and precisely and keep the platforms stable at the same time. Most leveling systems are implemented with hydraulic system, and they are time-variant nonlinear systems. To leveling both rapidly and steadily with required precision, a PID control strategy based on fuzzy theory was proposed. Electro-hydraulic proportional valve control hydraulic system model was created and analyzed, transfer function of hydraulic legs was obtained and fuzzy PID controller was created in this paper. The proposed method is simulated in Simulink. The simulation result shows that fuzzy PID controller can adjust the platform to horizontal position rapidly and steadily, and improve system performance.

Simulation and Research of New MW Wind Turbine Yaw Hydraulic System Based on AMEsim

This paper presents a new MW wind turbine yaw hydraulic system,and describes the working principle of the hydraulic system,derives kinetic equations of the electromagnetic proportional valve and the motor in the hydraulic circuit,uses AMEsim to establish a simulation model of the electromagnetic proportional valve control motor hydraulic system,sets parameters of main elements of the model,and simulates.given under the input current signal action,derives yaw motor shaft speed and time graphics,and analysis.

Characteristics Analysis of Proportional Control Valve on Vane Damp

The proportional flow control valve is not only one of the key competent of vane damp,but also the execution unit of shock absorber damping force's regulation .The proportional flow control valves self-designed will combine the structural design of proportional control valve and crate CFD model . The thesis analyzes its distribution of flow field by CFD and acquires experimental validation .It analyzes dynamic characteristics and determine the relationship of flow and opening and drive current. The proportional control valve test verifies the correctness, finally. It is basis for analyzing of damping characteristics about vane damp, which can be used other proportional control valve CFD study.

Neural Network Control for PPDCV Clinker Cooler System

Pilot Proportional Directional Control Valve (PPDCV) is used to control the clinker cooler actuator position for Cement Industries. PID controllers are satisfying control for the actuator position control with transient response and reduce steady state error. Uncertainty parameter cause unsmooth response small oscillation in actuator position. This work explains a neural network control for (PPDCV) system with uncertainty parameter, reduces the disturbance, and removes the oscillation in the response. The paper is focused on the possibilities of applying trained artificial neural networks for creating the system inverse models that are used to design inverse control algorithm for non-linear dynamic system. The simulation experiment is performed using Matlab and Simulink to show the response of these controllers.

2D21 Control schemes for an overlap type proportional directional control valve(The 12th International Conference on Motion and Vibration Control)

In a hydraulic control system(here, we call this a major control loop), a proportional directional control(PDC) valve with spool position feedback may work in minor(or inner) control loop. In this study the authors suggest control schemes to improve the performance of PDC valve control loop(a minor control loop). At first, the mathematical model for the PDC valve is obtained through an experimental identification process. Then, a dead-zone compensation scheme is devised. And the control schemes for the PDC valve are suggested so as to reject disturbances effectively, and to obtain good reference tracking ability. Finally, the suggested control schemes are verified through experiments.

Contour Error of the 3-DoF Hydraulic Translational Parallel Manipulator

The paper deals with a selected problem of contour error for the desired tracking trajectory of the spatial 3-DoF hydraulic translational parallel manipulator (TPM). The prototype hydraulic TPM consists of a fixed base and a moving platform connected by the joints with three hydraulic linear axes. The closed-loop kinematic chains of the hydraulic TPM create a 3-RRPRR structure in which revolute joints R and prismatic joints P step out. The three equal integrated electro-hydraulic axes are prismatic joints P in which hydraulic cylinders are integrated with position measuring systems and proportional directional control valves.

Study of Dynamic Characteristics about Controllable Vane Damp

The characteristic of controllable vane damp is about the relationship between choke opening and damp parameter of proportional flow control valve, the relationship between the input current of electromagnet and controllable damp parameter is available after knowing the characteristics of electromagnet. This is the basic of control system design and the central dynamic characteristics of vane damp. The structure of vane damp is analyzed and the flow model is established, to provide the theoretical guidance with the design, analysis and improvement of vane damp, a simple calculating and accurate analytical method is proposed.

Experimental Modelling and Identification of Compressible Flow through Proportional Directional Control Valves

This paper derives an empirical model of the air flow through a variable area orifice of a 5-port proportional valve, in function of pressures at the supply port and at the pneumatic cylinder, i.e. including the flow resistance of the connecting tubes and fittings, and the (quasi-static) valve’s

Development and speed control of water driven stage

Water driven stage is developed as a linear stage of the ultra-precision machine tool, especially, that is intentionally designed for the machining of small parts in size, such as optical mirrors and lenses. The water driven stage is mainly composed of a body of the stage and a table. The table is supported by water hydrostatic bearings and is driven by water hydraulic cylinder. Speed of the stage, determining the feed rate of the diamond turning, can be controlled by the flow rate into the water hydraulic cylinder. The paper deals with speed control of the stage. Mathematical models of the water driven stage and the proportional flow control valve are derived in order to design feedback control system. Performances of the designed feedback control system are verified via experiments and simulations. It is then verified that the steady state error is less than 0.5%. Step responses of the control system with a step input of the external load acting on the table are also tested, showing validity of the designed control system.

The Pneumatic Position Control System Based on Fuzzy-PID

Put forward a kind of control system to achieve precise positioning of the pneumatic cylinder, coring to PC upper monitor and using Visual C++ as the development platform. Establish an experimental platform of pneumatic cylinder positioning control system: selecting the parameter self-tuning Fuzzy-PID control algorithm, using the proportional directional control valve, standard cylinder, displacement sensordata acquisition card and other components. the use of MATLAB to simulate and optimize, carry out the actual experiment on the basis of simulation. The experimental results proved the effectiveness and correctness of Fuzzy PID in pneumatic control system.

Adaptive robust motion trajectory tracking control of pneumatic cylinders

High-accuracy motion trajectory tracking control of a pneumatic cylinder driven by a proportional directional control valve was considered. A mathematical model of the system was developed firstly. Due to the time-varying friction force in the cylinder, unmodeled dynamics, and unknown disturbances, there exist large extent of parametric uncertainties and rather severe uncertain nonlinearities in the pneumatic system. To deal with these uncertainties effectively, an adaptive robust controller was constructed in this work. The proposed controller employs on-line recursive least squares estimation (RLSE) to reduce the extent of parametric uncertainties, and utilizes the sliding mode control method to attenuate the effects of parameter estimation errors, unmodeled dynamics and disturbances. Therefore, a prescribed motion tracking transient performance and final tracking accuracy can be guaranteed. Since the system model uncertainties are unmatched, the recursive backstepping design technology was applied. In order to solve the conflicts between the sliding mode control design and the adaptive control design, the projection mapping was used to condition the RLSE algorithm so that the parameter estimates are kept within a known bounded convex set. Extensive experimental results were presented to illustrate the excellent achievable performance of the proposed controller and performance robustness to the load variation and sudden disturbance.

Undisturbed switching control of fuel flow-rate for a high-speed heat-airflow wind tunnel

According to the requirements of a high-speed heat-airflow wind tunnel experimental system, a fuel supply system based on variable frequency control technology and proportional throttle valve is designed. The mathematical model of the fuel supply system under the mode of the proportional throttle valve control and the variable frequency pump control is established. Because the fuel supply system has a pure time delay and the change of working conditions can cause the problem of time-variant parameters, a fuzzy proportion integration differentiation control strategy with Smith predictor is proposed. In addition, switching between the pump control mode and the valve control mode will bring disturbances, so two undisturbed switching methods are designed. The simulation and experimental results show that the proposed control strategy can overcome effects of the pure time delay and obtain a satisfactory control performance. The two undisturbed switching control methods designed in this paper can achieve the undisturbed switching of the fuel flow-rate control.

Compound sliding-mode predictive control for a temperature system of high-speed heat-airflow wind tunnel

The mathematical model of the temperature system under the mode of the proportional throttle valve control and the variable frequency pump control is established, respectively. A compound control strategy that consists of a compensation controller and a sliding-mode predictive feedback controller is designed. The compensation controller, which takes the change of the wind speed as parameter, is used to eliminate the impact on the system caused by the change of the working conditions (wind speed); the sliding-mode predictive feedback controller is used to solve the problems in the system such as time delay, time-varying parameters and disturbance. In order to solve the problem of temperature disturbance caused by the mode switch between pump control and valve control and the oil-rich combustion phenomenon in the high-temperature case, a method takes the ramp signal in which the slope is adjustable as a temperature setting signal is proposed. The experimental results show that the designed strategy obtains a satisfactory control performance and can achieve the temperature control with fast response time and no overshoot. In addition, it takes the ramp signal in which the slope is adjustable as the temperature setting signal can achieve the undisturbed switching control of the temperature and prevent the oil-rich combustion effectively.

Design of a laboratory hydraulic device for testing of hydraulic pumps

The present contribution deals with solves problem of research of testing device to monitor of hydrostatic pumps durability about dynamic loading under laboratory conditions. When carrying out the design of testing device are based on load characteristics of tractor hydraulic circuit, the individual characteristics of hydraulic components and performed calculations. Load characteristics on the tractors CASE IH Magnum 310, JOHN DEERE 8100, ZETOR FORTERRA 114 41 and Fendt 926 Vario were measured. Design of a hydraulic laboratory device is based on the need for testing new types of hydraulic pumps or various types of hydraulic fluids. When creating of hydraulic device we focused on testing hydraulic pumps used in agricultural and forestry tractors. Proportional pressure control valve is an active member of the hydraulic device, which provides change of a continuous control signal into relative pressure of operating fluid. The advantage of a designed hydraulic system is possibility of simulation of dynamic operating loading, which is obtained by measurement under real conditions, and thereby creates laboratory conditions as close to real conditions as possible. The laboratory device is constructed at the Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra.

Theoretical and Experimental Analysis of a Coupled System Proportional Control Valve and Hydraulic Cylinder

The aim of this paper is to analyze the driving system actuated by a proportional directional control valve on a hydraulic cylinder. In order to evaluate the dynamic interaction between the proportional valve and the cylinder theoretical analysis, numerical simulations as well as experimental test are performed. Coupling cylinder and proportional valve, it is very important to know the ratio of their natural frequencies. In particular, if the valve is characterized by a lower natural frequency, its behavior prevails so that no resonance peak can be observed on the coupled system. On the contrary, resonance phenomena can be observed in all the other cases. It is important that these phenomena are preventively taken into account to realize a precise and accurate control system of a hydraulic axle.At last, three different control methods are tested on the coupled system:Proportional Integral Derivative technique (PID), the adaptive One-Step-Ahead control technique, and an expert control technique and the obtained precisions are very interesting.

피드백 선형화 보상기와 외란 관측기를 이용한 2개 유압 실린더의 동기 제어

In the study, a control strategy using a feedback linearization compensator and a disturbance observer was suggested and applied to the synchronization control of two hydraulic cylinders. The hydraulic system consists of a proportional directional control valve with overlap characteristic near the neutral position, a conventional hydraulic cylinder and an external load. The control performances of the system were verified through numerical simulations. From the simulations, it was ascertained that excellent control performances were obtained with the suggested control strategy.

A Hybrid of Force and Position Control with Energy Saving in the Electro-Hydraulic System

Generally, the electro-hydraulic system (EHS) has force and position controls. The control of these parameters to the desired value multiple PID controllers are often used, which are sensitive to changes in system parameters. In addition, the existing EHS is often used as a single proportional direction control valve (PDCV) to control those parameters that cause loss and waste energy. Therefore, in this paper, a fuzzy controller is proposed to control force and position. Simultaneously, the EHS that is used for control will be added the inverter to adjust the speed of the electric motor (EM) to drive a fixed displacement gear pump, and a proportional pressure relief valve (PPRV), in order to save energy. A proposed fuzzy controller and the EHS are implemented to the hydraulic press. The experimental results showed that the hybrid of force and position control by using a fuzzy controller has a superior performance compared to the multiple PID controllers. Moreover, the proposed EHS is also more effective in saving power consumption than conventional EHS.