Control reconfigurability of bilinear hydraulic drive systems

ENSURING QUALITATIVE-ACCURACY CHARACTERISTICS DURING RESTORING OF VEHICLE PARTS

Tekhnicheskiy servis mashin ◽

10.22314/2618-8287-2021-59-3-116-121 ◽

2021 ◽

Vol 3 (144) ◽

pp. 116-121

Author(s):

Nikita A. Pen’kov ◽

◽

Oleg A. Sidorkin ◽

Sergey Yu. Zhachkin ◽

Anatoliy I. Zavrazhnov ◽

...

Keyword(s):

Wear Resistance ◽

Current Density ◽

Hydraulic Drive ◽

Research Purpose ◽

Working Fluid ◽

Agricultural Machinery ◽

Servo Valve ◽

Contact Points ◽

Drive Systems

One of the most common reasons for the failure of hydraulic drive systems for agricultural machinery is the working fluid leak in the contact points of the rubbing surfaces of hydraulic blocks. The application of composite coatings based on chromium on the contacting surfaces allows you to restore the defect in the shape of the part caused by wear, as well as reduce the friction coefficient at the contact points, which positively affects the wear resistance of the part. (Research purpose) The research purpose is in developing technologies for restoring parts of agricultural machinery with predetermined operational properties. (Materials and methods) A servo valve, widely used in various hydraulic drive systems, was used as an experimental sample. Its working surface was restored with a composite coating applied by electroplating to increase the wear resistance of the servo valve. (Results and discussion) Authors conducted a series of direct measurements under the same conditions. The article presents the de-pendence of the microhardness on the parameters of the electrolysis mode and the thickness of the applied coating using the method of least squares. The nature of changes in microhardness and residual stresses was evaluated to determine the quality of the coatings. The article presents the dependences of these indicators on various control parameters (current density, temperature, tool pressure). The equations of the regression of the main qualitative and accuracy characteristics of the parts were deter-mined using the apparatus of the theory of experimental planning. (Conclusions) The article presents the method for predicting coatings of a given quality, taking into ac-count the influence of the current density and the temperature of the electrolyte during electrolysis on the nature of the precipitation obtained. The influence of the tool pressure on the depth of deformation of the formed layers was estimated. This approach allows us to evaluate the nature of the stress distribution in the formed coating and the quality of the restored parts.

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The method of dynamic operating modes investigation in electrohydraulic drive systems with improved accuracy of positioning executive elements

MATEC Web of Conferences ◽

10.1051/matecconf/201822604024 ◽

2018 ◽

Vol 226 ◽

pp. 04024

Author(s):

Valeriy V. Grechikhin ◽

Galina A. Galka ◽

Anatoliy I. Ozerskiy ◽

Mikhail E. Shoshiashvili

Keyword(s):

Mutual Influence ◽

Hydraulic Drive ◽

Joint Work ◽

Operating Modes ◽

Hydraulic Machines ◽

Dynamic Operating ◽

Electrohydraulic Drive ◽

Drive Systems ◽

Improved Accuracy ◽

Executive Elements

The article describes the method of dynamic operating modes investigation in electrohydraulic drive systems with improved accuracy of positioning output element. The method is the evolution of the fundamental positions of the mechanics of continuous media with moving boundaries as applied to the research of non-stationary processes accompanying the operation of hydraulic drive systems with piston hydraulic machines. The method is based on generalized modeling (technical, physical, mathematical and computer), takes into account the peculiarities of mutual influence of electric and hydraulic machines during their joint work as part of the electrohydraulic drive, which raises the level and adequacy of actuators simulation, as well as the reliability of the assessment of their technical condition. The method extends the field of research, improves the accuracy of the calculation of the positioning of the executive elements, taking into account the different dynamic modes of the drives under study.

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Optimal feedforward control of hydraulic drive systems with long pipelines

PAMM ◽

10.1002/pamm.201900195 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Christopher Pietschnig ◽

Lukas Marko ◽

Wolfgang Kemmetmüller ◽

Andreas Kugi

Keyword(s):

Feedforward Control ◽

Hydraulic Drive ◽

Drive Systems

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Concept and modelling of the electrohydraulic valve with DC and stepper motors

MATEC Web of Conferences ◽

10.1051/matecconf/201925206003 ◽

2019 ◽

Vol 252 ◽

pp. 06003 ◽

Cited By ~ 1

Author(s):

Dominik Rybarczyk

Keyword(s):

Hydraulic Drive ◽

Dc Motor ◽

Stepper Motor ◽

Proportional Valve ◽

Positioning Accuracy ◽

Accuracy Requirement ◽

Stepper Motors ◽

New Type ◽

Drive Systems ◽

Electrohydraulic Valve

The article describes concept and modelling of a new type of electrohydraulic valve controlled by the combination of a stepper motor and a DC motor. The aim of this invention is to use in the proportional valve two motors with the different properties. Both motors are responsible for the movement of a valve spool. The stepper motor and the DC motor are connected to a shaft by using a bellows coupling. Transfer from rotary to linear motion is performed by use of a bolt-nut system. According to the invention, presented here valve can be used in hydraulic drive systems with high positioning accuracy requirement. The author was granted a patent no. P.421994 on the invention described in this paper.

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A Concept of a Knowledge-Based Assistance System for Servohydraulic Drive Design

Volume 4: Design, Analysis, Control and Diagnosis of Fluid Power Systems ◽

10.1115/imece2007-41402 ◽

2007 ◽

Author(s):

Kristof Schlemmer ◽

Hubertus Murrenhoff

Keyword(s):

Expert System ◽

Hydraulic Drive ◽

Software Tool ◽

Interactive Software ◽

Hydraulic Control ◽

Development Environment ◽

Industrial Enterprises ◽

Knowledge Based ◽

Comprehensive Survey ◽

Drive Systems

Outsourcing of drive engineering is a tendency to be observed in many industrial enterprises today. As in-house expertise diminishes, competitiveness of hydraulic drive systems compared to electrical drives gains importance. Servohydraulic control systems, however, require very specific and complex approaches to circuit and control design. They are thus demanding on the designer’s knowledge and experience, which often leads to hydraulic solutions being implemented unsatisfactorily or not at all. The concept developed in this paper therefore aims at providing support in drive system design to inexperienced customers or sales people. In order to make the diversity of existing expertise accessible and utilizable, a knowledge-based approach is proposed. The objective is seen in an interactive software tool that guides the user through the iterative process of analyzing the problem, planning and designing the most appropriate drive solution. Requirements and selection criteria for a development environment are specified, and an expert system shell is selected as a means of implementation. A taxonomy of linear hydraulic servo drives is created that provides a frame for an object-oriented knowledge base. Knowledge extracted from text books and expert interviews is integrated into the system as a collection of rules and facts. Special attention is paid to the selection of a control strategy that delivers optimum performance beyond the capability of standard PID controllers. A comprehensive survey of hydraulic control technology is to ascertain that the developed expert system employs both approved and novel techniques to the benefit of overall system performance.

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