The Effects of Orifice Sizes on a Hydraulic Servo Valve Control System

2013 ◽  
Author(s):  
Marshall McNea ◽  
Shanzhong (Shawn) Duan
Keyword(s):  
Control System ◽  
Hydraulic System ◽  
Pressure Pulse ◽  
Dynamical Behavior ◽  
Servo Valve ◽  
External Orifice ◽  
Hydraulic Servo ◽  
Hydraulic System Design ◽  
Valve Control ◽  
Orifice Size

Precision control for a force controlled hydraulic system can be achieved through the use of a flow controlled servo valve. Servo valves can be manufactured with a spool that is overlapped, an under lapped, or has a zero lap. A servo valve with a zero lap is desirable for a responsive hydraulic system without leakage, but has the disadvantage of creating a pressure pulse upon opening the valve. The hydraulic system for this setup involves having a double end, double action actuator that will have a cyclic motion generating multiple pressure waves in the system. Including an orifice in the system, which will function as a dampener, can reduce the pressure pulses. Traditional locations for orifices have been in the spool and on the actuator piston. For this hydraulic system design an external orifice will be introduced into the system via the use of an orifice plate included in the hydraulic fittings. This change allows for the ability to change the orifice size. Changing the orifice size to determine the effects on the systems control will be analyzed. The intended outcome is to demonstrate that different sized orifice plates will cause changes to the control system behavior so that an experimental formula will be established for this approach of a zero lap valve with an external damper for reduction of overshooting of dynamical behavior of the valve spool.

The Design of Comprehensive CAT Test Rig for Electro-Hydraulic Servo Valve

2013 ◽  
Vol 389 ◽  
pp. 394-397
Author(s):  
Shuai Feng ◽  
An Bin Xu ◽  
Dong Li
Keyword(s):  
System Design ◽  
Software Design ◽  
Virtual Instrument ◽  
Hydraulic System ◽  
Test Rig ◽  
Servo Valve ◽  
Hydraulic Servo ◽  
Instrument Technology ◽  
Hydraulic System Design

By comparing the limitation of traditional test rig for electro-hydraulic servo valve and the advantages of CAT test rig for electro-hydraulic servo valve, this paper demonstrates an overall CAT test rig design including hydraulic system design and test software design. This work applies virtual instrument technology based on LabVIEW and adopts OPC standard to realize real-time communication between computer and PLC. Eventually as a case study, a test example of a well-functional servo valve is presented to show the validity and accuracy of the test rig.

scholarly journals Study on Electro-hydraulic Servo Valve Control System of Series Manipulator

2017 ◽  
Vol 10 (3) ◽  
pp. 289-302
Author(s):  
Zhang Daode ◽  
Yan Pian ◽  
Wang Zhouxing ◽  
Wu Yuan
Keyword(s):  
Control System ◽  
Servo Valve ◽  
Hydraulic Servo ◽  
Valve Control

Research on the Impact Pressure of the Hydraulic Rolling-Cut Shear

2010 ◽  
Vol 145 ◽  
pp. 410-413 ◽  
Author(s):  
Jing Wang ◽  
He Yong Han ◽  
Qing Xue Huang ◽  
Jun Wang
Keyword(s):  
Hydraulic System ◽  
Impact Pressure ◽  
Direct Impact ◽  
Actual Situation ◽  
Work Situation ◽  
Servo Valve ◽  
Indirect Impact ◽  
Hydraulic Servo ◽  
Hydraulic Servo System ◽  
The Impact

The reasons for impact pressure are obtained by the research the hydraulic system of Hydraulic Rolling-Cut Shear. The impact pressure of hydraulic system is divided into direct impact and indirect impact. Based on analyzing the actual situation the measures should be taken to reduce the impact pressure when design hydraulic system. The suitable length of pipeline can improve the performance of the hydraulic system because the length is important for the impact pressure. The accumulator can absorb impact pressure and improve the work situation of servo valve. Therefore, the suitable accumulators should be set in the hydraulic system. The study provides theory basis for the pipe design of large hydraulic servo system.

Experiment Study on Performances of Servo Pump Used in Hydraulic Press Machine

2012 ◽  
Vol 516-517 ◽  
pp. 892-895 ◽  
Author(s):  
Jun Gao ◽  
Guo Yi Yan ◽  
Gen Yun Peng ◽  
Guan Nan Xi
Keyword(s):  
Energy Efficiency ◽  
Control System ◽  
Working Conditions ◽  
Hydraulic System ◽  
Test Bench ◽  
Hydraulic Press ◽  
Experiment Study ◽  
Two Systems ◽  
Positive Meaning ◽  
Valve Control

As we known, the energy efficiency of pump-control system is higher than valve-control system. So, using pump-control system to replace valve-control system has a positive meaning to improve the energy efficiency in hydraulic press machine. In order to research the performance of servo pump used in hydraulic press machines, the present study is conducted. First, a test bench for comparison of pump-control and valve-control system is established. In this test bench, the pump of former valve-control system and the servo pump are settled. These two pumps are switched by solenoid to supply oil for the hydraulic system. Then, host PC, target PC, I/O board and other hard-wares are connected. Soft-wares and the corresponding driver board are applied to collect data. In order to test the performances of the pressure, velocity and displacement under the condition of the valve-control system and pump-control system, the two systems are tested with the same working conditions. The performance of repeatability and energy efficiency are also obtained. The results show that it’s feasible to apply servo pump to hydraulic press machine. And under the pump-control condition, the velocity and pressure performance of press machine is more stable.

Design of the Hydraulic System of Lead Plate Coiling Machine

2014 ◽  
Vol 937 ◽  
pp. 336-340
Author(s):  
Hui Sen ◽  
Rui Bo Yuan ◽  
Rong Li
Keyword(s):  
Control System ◽  
Hydraulic System ◽  
Position Control ◽  
Torque Control ◽  
Tension Control ◽  
Hydraulic Motor ◽  
Relief Valve ◽  
Lead Plate ◽  
Hydraulic Servo ◽  
Close Loop Control

This paper mainly introduces the process of lead electrolysis, the structure and working principle of lead plate coiling machine and Its’ parts, coiling machine components. First of all, rewind section hydraulic system adopts a return to the oil throttle speed control, it is stable and can bear a certain change load, can overcome the stage before the tension fluctuation of the impaction to the rotation speed of hydraulic motor. Secondly, speed and tension control system adopt electro-hydraulic servo valve and proportional relief valve are respectively to the drum speed and output torque control,it has high precision and accurate in speed and tension control. contact coiling section use electro hydraulic servo position control system with close loop control to improve the accuracy of position control. Finally, calculate parameters of each working section of hydraulic control system , verify the hydraulic component model and the rationality of the hydraulic circuit.

Performance Verification of Semi-Active and Active Impact Control Systems

2004 ◽  
Vol 10 (6) ◽  
pp. 811-836
Author(s):  
Dong Hwan Kim ◽  
Moon-Chul Choi ◽  
Joo-Hoon Baek
Keyword(s):  
Control System ◽  
Control Systems ◽  
Computer Simulations ◽  
Proportional Valve ◽  
Servo Valve ◽  
External Orifice ◽  
Piston Displacement ◽  
External Impact ◽  
And Control ◽  
Short Impulse

A semi-actively controlled impact systemis studied, which adjusts an impulse exerted by the external impact. Also, an active impact control system using a servo valve is introduced, and these performances are compared. The systems should respond to the extremely short impulse and control the impulse within a highly fast interval. Both the semi-active and the active control systems utilize an external orifice in the form of a proportional valve or a servo valve, which adjusts its opening area to control the pressure and piston displacement. These devices overcome the temperature and viscosity variations due to continuant operations, and keep the desired pressure difference and the displacement at a desirable level. In this work, two prototypic impact systems controlled by semi-active and full active operations are designed and manufactured. Through computer simulations and experiments, the possibility of controlling the pressure and displacement of an impact control system is verified.

scholarly journals Research on the Nonlinear Characteristic of Flow in the Electro-Hydraulic Servo Pump Control System

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 814
Author(s):  
Tiangui Zhang ◽  
Gexin Chen ◽  
Guishan Yan ◽  
Cheng Zhang ◽  
Yuan Li ◽  
...  
Keyword(s):  
Control System ◽  
Hydraulic System ◽  
Dead Zone ◽  
Servo Motor ◽  
Saturation Zone ◽  
Output Displacement ◽  
Positive Displacement ◽  
System Flow ◽  
Displacement Pump ◽  
Hydraulic Servo

In an electro-hydraulic servo system, the system flow is used as an intermediate variable to control the output displacement/force/speed of the actuator, and it plays the role of a medium for energy transmission and conversion. Therefore, the control of the system flow is the essence of state control for the system actuator. The purpose of this paper is to study the non-linear characteristics of pump control system flow and pave the way for high-performance control of the system. Based on the flow partition idea, the system output flow is divided into the dead zone, load zone, and saturation zone. We establish a mathematical model of the hydraulic system to analyze and study the effect of the nonlinear characteristics of the servo motor and the positive displacement pump on the system flow partition characteristics. We focus on the effects of the positive displacement pump shear flow internal leakage, pressure difference flow internal leakage, oil compression, servo motor rotation friction, and servo motor torque reserve rate on the system flow output, and analyze the partition characteristics of the system flow under different working conditions. We provide a theoretical basis for a high-precision control strategy for a hydraulic system.

scholarly journals Bricklaying Robot Lifting and Levelling System

2021 ◽  
Vol 23 (4) ◽  
pp. B257-B264
Author(s):  
Piotr Wos ◽  
Ryszard Dindorf ◽  
Jakub Takosoglu
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Design Process ◽  
Hydraulic System ◽  
Servo Drive ◽  
Synchronization Errors ◽  
Position Errors ◽  
Hydraulic Servo ◽  
The Mathematical Model ◽  
Servo Drive System

The article presents the concept of building and controlling a Bricklaying Robotic System (BRS). The research presents the design process and how to control a four-cylinder electro-hydraulic servo drive system. The article presents a mathematical model and optimizes the process of aligning the mobile support platform of the masonry robot. The lifting mechanism was presented and its kinematic analysis performed. The mathematical model of the hydraulic system was described. The control system, designed for the masonry robot lifting platform, includes position errors for a single drive axis and synchronization errors between the axes.

Sign in / Sign up

Export Citation Format

Share Document