CN102521461B - Simulation modeling method of electro-hydraulic servo valve based on Modelica language - Google Patents
Simulation modeling method of electro-hydraulic servo valve based on Modelica language Download PDFInfo
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- CN102521461B CN102521461B CN201110430695.3A CN201110430695A CN102521461B CN 102521461 B CN102521461 B CN 102521461B CN 201110430695 A CN201110430695 A CN 201110430695A CN 102521461 B CN102521461 B CN 102521461B
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Abstract
The invention relates to the technical field of electro-hydraulic servo valve simulation systems, in particular to a simulation modeling method of electro-hydraulic servo valve based on a Modelica language, which includes the following steps: 1, system disassembly; 2, component level modeling; 3, subsystem level modeling; 4, system level modeling; 5, simulation control; and 6, simulation result demonstration. The simulation modeling method of the electro-hydraulic servo valve based on the Modelica language utilizes multi-territoriality, non-causality and object orientation of the Modelica language to perform secondary development, an obtained electro-hydraulic servo valve simulation model can faithfully reflect operating conditions and characteristics of the electro-hydraulic servo valve and substitute a electro-hydraulic servo system to conduct further system analysis and design, and the simulation modeling method can provide excellent analysis tools and analysis approaches for servo researching and working personnel.
Description
[technical field]
The present invention relates to electrohydraulic servo valve analogue system technical field, specifically a kind of electrohydraulic servo valve emulation modelling method based on Modelica language.
[background technology]
In actual production practices, the engineering machinery such as concrete pumping car and autocrane need to realize certain control accuracy and dynamic property, and traditional hydraulic system lacks the process control to hydraulic actuator, thereby cannot realize higher control accuracy and outstanding dynamic property.Therefore, in existing hydraulic system, introducing the Electro-hydraulic element of can implementation procedure controlling, to realize compared with high control precision be very necessary with better dynamic property.The Electro-hydraulic element that uses implementation procedure to control, the control method of electro-hydraulic servo element is called electro-hydraulic servo control, and as servo-controlled Yi Ge branch, it can meet the requirement of engineering machinery field to control accuracy and dynamic property with flying colors.
Servo-drive system, i.e. output can reappear the automatic control system of inputting Changing Pattern automatically, quickly and accurately with certain precision; The servo-drive system that electrohydraulic servo-controlling system adopts electrohydraulic control element and hydraulic actuator to form.Electrohydraulic servo valve is as the interface element that the electric part of system and hydraulic part are connected, the small electric signal of input can be converted to powerful hydraulic pressure signal output, and then hydraulic actuator is realized and being controlled, be the important component part of electrohydraulic servo-controlling system.
In the system building of concrete pumping car and autocrane, hydraulic system has occupied very most of.But in the commercial liquid pressing system storehouse Hylib of Modelica language, this critical elements of servo-valve is not carried out to modeling, and for direction pilot valve, also avoided the feature of electrohydraulic servo valve electricity, magnetic, machine, liquid, the multi-field coupling of control, only used the naive model of signal current control.First this be unfavorable for the Modeling and Design of complex hydraulic system, and secondly not outstanding Modelica Multi-disciplinary Modeling language is in the superiority of processing multi-field coupled problem.Thereby, research for the Modelica modeling of the element of this electricity of electrohydraulic servo valve, magnetic, machine, liquid, the multi-field coupling of control, contribute to the expansion in Modelica hydrostatic control storehouse and enriching of engineering machinery storehouse, and then realize the High Precision Simulation of engineering machinery hydraulic control system and Optimization Modeling design.
Early stage servo-valve modeling is to utilize the mode of Simultaneous Equations to carry out modeling.Development along with control theory, occurred using control block diagram and signal stream to carry out the analysis means of Causal Analysis, as accompanying drawing 1, these means become the usual method of the modeling and control of research electrohydraulic servo valve, the method is all set forth in the Digital Simulation of < < Dual Injector Baffle formula force feedback electro-hydraulic servo valve and CAD design program > > to some extent the < of Herbert E.Merritt < Hydraulic Control Systems > > mono-book and Mr. Tian Yuandao.The method is a kind of very ripe modeling method.But, use causality control block diagram modeling method to exist certain deficiency, for example can not be from principle of work and the mathematical model of bottom component reflection electrohydraulic servo valve, when setting up, block diagram need to consider the calculating causality of each physical quantity, be not easy to revise and change element, primary element cannot be reused in the modeling of different electrohydraulic servo valves, and the control block diagram model of servo-valve is not easy to the Hydrauservo System of substitution integral body and analyzes etc.
Therefore there is following defect in traditional electrohydraulic servo valve: analysis means can not be from principle of work and the mathematical model of bottom component reflection electrohydraulic servo valve, when setting up, block diagram need to consider the calculating causality of each physical quantity, be not easy to revise and change element, primary element cannot be reused in the modeling of different electrohydraulic servo valves, and the control block diagram model of servo-valve is not easy to the Hydrauservo System of substitution integral body and analyzes.
[summary of the invention]
Object of the present invention is exactly will solve above-mentioned deficiency and a kind of electrohydraulic servo valve emulation modelling method based on Modelica language is provided, there is object orientedness, non-causality and multi-field property, existing electrohydraulic servo valve analysis means is integrated and reformed.
Design for achieving the above object a kind of electrohydraulic servo valve emulation modelling method based on Modelica language, it comprises the steps:
1) system is disassembled: first electro-hydraulic servo valve system is decomposed, obtain subsystem, and then the subsystem obtaining is decomposed, obtain element;
2) component-level modeling: the primary element obtaining for decomposition carries out modeling analysis; that builds electric field, magnetic field, machinery, hydraulic pressure and control field is not included in the primary element in the basic storehouse of Modelica, Magnetic storehouse and Hylib storehouse, between described electric field, magnetic field, machinery, hydraulic pressure and control field, by the interface element of building, is associated;
3) subsystem irrespective of size modeling: the element that utilizes component-level modeling to obtain, and the element in the basic storehouse of Modelica, Magnetic storehouse, hydraulic system storehouse Hylib, the subsystem of electrohydraulic servo valve is built;
4) system-level modeling: the subsystem that utilizes the modeling of subsystem irrespective of size to obtain is built complete electro-hydraulic servo valve system;
5) Simulation Control: the electrohydraulic servo valve model specification simulation parameter, step-length and the time that complete modeling are compiled to emulation;
6) last, simulation result demonstration.
Described subsystem comprises torque-motor, nozzle flapper amplifier, spool, feedback rod and valve body.
Described torque-motor subsystem is decomposed into stator subsystem, armature subsystem.
Described interface element comprises translation rotation interface, air gap, nozzle and the positive and negative valve open element of developing in interface element, component-level modeling in Modelica base library, Magnetic storehouse and Hylib storehouse.
Beneficial effect of the present invention: the multi-field property, non-causality and the object orientedness that utilize Modelica language, carry out secondary development, the electrohydraulic servo valve realistic model obtaining can reflect working condition and the characteristic of electrohydraulic servo valve faithfully, and its substitution electrohydraulic servo system can be carried out to further Design & Analysis of System, can provide outstanding analysis tool and analysis means for servo research and staff.
[accompanying drawing explanation]
Fig. 1 is traditional electrohydraulic servo valve analytical approach schematic diagram;
Fig. 2 is structured flowchart schematic diagram of the present invention;
Fig. 3 is analytic process schematic diagram of the present invention;
Fig. 4 is translation rotation interface element schematic diagram;
Fig. 5 is air gap element schematic diagram;
Fig. 6 is nozzle member schematic diagram;
Fig. 7 is positive and negative valve open element schematic diagram;
Fig. 8 is stator subsystem schematic diagram;
Fig. 9 is armature subsystem schematic diagram;
Figure 10 is nozzle flapper amplifier subsystem schematic diagram;
Figure 11 is spool subsystem schematic diagram;
Figure 12 is feedback rod subsystem schematic diagram;
Figure 13 is valve body subsystem schematic diagram;
Figure 14 is electrohydraulic servo valve system schematic;
Figure 15 is that the electrohydraulic servo valve that modeling obtains is applied in the schematic diagram in electro hydraulic servo system design.
Figure 16 is the response curve schematic diagram of electro-hydraulic servo valve system.
[embodiment]
Below in conjunction with accompanying drawing, the present invention is done to following further illustrating:
As shown in Figure 1, be traditional electrohydraulic servo valve analytical approach, the analytical approach of this use block diagram cannot reflect the design feature of electrohydraulic servo valve strictly according to the facts, parameter modification inconvenience, and be difficult for substitution servo-drive system and carry out whole design and analysis.
As shown in accompanying drawing 2, Fig. 3, accompanying drawing 2 is fundamental analysis principle of the present invention, and the object orientedness for Modelica language, decomposes targetedly to system, and the element that uses modeling to complete carries out system building.Accompanying drawing 3 is analytic process of the present invention, the electrohydraulic servo valve model specification simulation parameter, step-length and the time that complete modeling is compiled to emulation, and then obtain 2D curve and 3D animation, thereby apply reference is provided for engineering.
The electrohydraulic servo valve simulation modeling step that the present invention is based on Modelica language comprises: system is disassembled, component-level modeling, the modeling of subsystem irrespective of size and system-level modeling.Its fundamental analysis principle comprises top-down system decomposition and system building from bottom to top.First electro-hydraulic servo valve system is decomposed, obtain some subsystems; And then the subsystem obtaining is decomposed, obtain the element of different field.After the primary element obtaining for decomposition carries out modeling analysis, use it to be built into electrohydraulic servo valve subsystem, and then use and to build the subsystem obtaining and set up complete electro-hydraulic servo valve system.For electro-hydraulic servo valve system, can be divided into: the subsystems such as torque-motor, nozzle flapper amplifier, spool, feedback rod and valve body, each subsystem inside can decomposite the primary element in the fields such as electric field, magnetic field, machinery, hydraulic pressure and control.
For component-level modeling, the basic storehouse of Modelica and other business or non-commercial storehouse provide some primary elements that can directly use, singularity for electrohydraulic servo valve, the element that other are not included in the basic storehouse of Modelica and business storehouse or non-commercial storehouse, can obtain by self-developing.Primary element for fields such as electric field, magnetic field, machinery, hydraulic pressure and controls, the present invention uses electric field, magnetic field, machinery, hydraulic pressure and the control field primary element in the basic storehouse of Modelica, Magnetic storehouse and tri-storehouses of hydraulic system storehouse Hylib, and the while is for the multi-field characteristic self-developing element of electrohydraulic servo valve.For Multi-disciplinary Modeling, its key issue is the interface element between multi-field, for the characteristic of electrohydraulic servo valve and the transformational relation between field, has write translation rotation interface, air gap, nozzle and positive and negative valve open element (as accompanying drawing 4-Fig. 7).
Utilize element that component-level modeling obtains and the element in the basic storehouse of Modelica, Magnetic storehouse and hydraulic system storehouse Hylib, the torque-motor of electrohydraulic servo valve, nozzle flapper amplifier, spool, feedback rod and valve body are carried out to system building, wherein, for easy analysis, torque-motor subsystem is decomposed into stator and two subsystems of armature (as accompanying drawing 8-Figure 13).
As shown in Figure 4, be translation rotation interface element.The many bodies storehouse that includes computer memory problem in mechanical motion bag in the basic storehouse of Modelica, the rotation storehouse of straight-line translation storehouse and rotational problems.In the modeling process of hydraulic efficiency servo-valve, because hydraulic efficiency servo-valve is a plane motion model, use many bodies storehouse to carry out Modeling Calculation amount bigger than normal, so use translation storehouse and rotation storehouse, carry out modeling, and the translation interface of writing between a translation storehouse and rotation storehouse can reduce computation complexity, the uncertainty of minimizing model.Its fundamental equation is:
s＝l|θ
τ＝l|f
In formula
As shown in Figure 5, air gap element is the interface element that connects magnetic field and mechanical field, by the variation of its magnetic flux, can cause the variation of gas length.Its fundamental equation is:
In formula
As shown in Figure 6, nozzle member is equivalent to settable orifice, and when the spacing of nozzle flapper changes, flow and pressure drop by nozzle also produce corresponding variation, and it meets following equation:
In formula
As shown in Figure 7, forward and negative sense valve opening are to open and close for simulating the valve opening that between spool and valve body, relative motion causes the element that situation is write.For forward opening, when displacement is that timing allows hydraulic oil to pass through, on the contrary can not; Oppositely opening is contrary.It meets following equation:
In formula
As shown in Figure 8, be stator subsystem, it is comprised of permanent magnet and four air gaps, and reserves translation interface and magnetic field interface, in order to being connected with armature subsystem.
As shown in Figure 9, be armature subsystem, wherein include electromagnetic conversion interface, the magnetic connected with stator, translation interface and be connected nozzle flapper subsystem and the rotary connector of feedback rod subsystem.In addition, in armature subsystem, include the bourdon tube parts that restriction armature rotates, for the convenience of modeling and simulating, also the uniform load equivalence of armature is become to a rotatory inertia load, and be connected with bourdon tube.
As shown in Figure 10, for the nozzle baffle type hydraulic amplifier in electrohydraulic servo valve can be reduced to a Hydraulic bridge model being comprised of two fixed orifices and two variable orifices (nozzle), wherein, fixed throttle port is used the Orifice assembly in Hylib storehouse, and settable orifice (nozzle) modeling voluntarily.When the liquid of two variable orifices is led variation, cause Hydraulic bridge two output terminals to produce pressure reduction, and then control spool and move.Hydraulic connecting terminal in this subsystem is connecting fluid potential source, oil return and spool respectively.
As shown in Figure 11, spool subsystem is comprised of equivalent spool quality and two Chamber parts.Nozzle flapper load is connected on spool two ends, promotes valve core movement.The translation interface at equivalent mass place connects valve body subsystem, thus the aperture of control valve port etc.
As shown in Figure 12, be feedback rod subsystem, its establishment is relatively simple, translation rotation interface and torsion spring, consists of.
As shown in Figure 13, valve body is formed by connecting by two forward valve openings and two reversing valve openings.The displacement of valve is introduced by spool subsystem, can determine aperture and the running of hydraulic power oil direction of each valve port.Except connecting the two-terminal of load, two ends connecting fluid potential source and oil return in addition.
As shown in Figure 14, be the electrohydraulic servo valve model that the subsystem that utilizes the modeling of subsystem irrespective of size to obtain builds, the visible model that from top to bottom decomposes and build is from the bottom to top very succinct, and, for the adjustment of electro-hydraulic servo valve system, be beneficial to realization.
As shown in Figure 15, be the practical application in servo-drive system of the electro-hydraulic servo valve system built.
As shown in Figure 16, be the response curve of servo-drive system, visible the present invention can be applied among the design setting model of servo-drive system, for engineering staff provides auxiliary and instructs.
Claims (4)
1. the electrohydraulic servo valve emulation modelling method based on Modelica language, is characterized in that, comprises the steps:
1) system is disassembled: first electro-hydraulic servo valve system is decomposed, obtain subsystem, and then the subsystem obtaining is decomposed, obtain element;
2) component-level modeling: the primary element obtaining for decomposition carries out modeling analysis, that builds electric field, magnetic field, machinery, hydraulic pressure and control field is not included in the primary element in the basic storehouse of Modelica, Magnetic storehouse and Hylib storehouse, between described electric field, magnetic field, machinery, hydraulic pressure and control field, by the interface element of building, be associated, described interface element is translation rotation interface, air gap, nozzle and positive and negative valve open element;
3) subsystem irrespective of size modeling: the element that utilizes component-level modeling to obtain, and the element in the basic storehouse of Modelica, Magnetic storehouse, hydraulic system storehouse Hylib, the subsystem of electrohydraulic servo valve is built;
4) system-level modeling: the subsystem that utilizes the modeling of subsystem irrespective of size to obtain is built complete electro-hydraulic servo valve system;
5) Simulation Control: the electrohydraulic servo valve model specification simulation parameter, step-length and the time that complete modeling are compiled to emulation;
6) last, simulation result demonstration.
2. the method for claim 1, is characterized in that: described subsystem comprises torque-motor, nozzle flapper amplifier, spool, feedback rod and valve body.
3. method as claimed in claim 2, is characterized in that: described torque-motor subsystem is decomposed into stator subsystem, armature subsystem.
4. the method as described in claim 1,2 or 3, is characterized in that: described interface element comprises translation rotation interface, air gap, nozzle and the positive and negative valve open element of developing in interface element, component-level modeling in Modelica base library, Magnetic storehouse and Hylib storehouse.
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| CN105445581B (en) * | 2015-11-27 | 2018-05-22 | 苏州同元软控信息技术有限公司 | A kind of fault detection system and its method based on Modelica models |
| CN106250608B (en) * | 2016-07-27 | 2019-03-08 | 北京航空航天大学 | A kind of failure management method based on Modelica model |
| CN106682323B (en) * | 2016-12-30 | 2019-11-12 | 苏州同元软控信息技术有限公司 | A kind of converting system and its method that framework model is converted to Dynamic Simulation Model |
| CN109488657A (en) * | 2019-01-07 | 2019-03-19 | 大连理工大学 | A kind of emulation modelling method of jet pipe electrohydraulic servo valve |
| CN116241526B (en) * | 2023-05-12 | 2023-07-28 | 苏州海卓伺服驱动技术有限公司 | Intelligent servo valve mode adjusting method and system |
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