比例多路阀的数字式控制

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摘要

电液比例多路换向阀（简称比例多路阀）的应用在近十多年来有明显的增长。

它在功能上有下列不可取代的优点：满足工程机械使用上电控与手动二种功能同

时存在的要求；具有比例调节的功能，满足许多工程机械上运动过程受控的要求；

采用负载敏感技术，满足阀控或泵控的节能要求。但随着自动化技术的发展，对

多路阀的控制精度、响应速度、自动化程度等性能有了更高的要求。虽然比例阀

先导控制的多路阀能满足要求，但比例阀构成的模拟式比例控制，如果要求计算

机控制，还必须通过 A/D、D/A 接口元件与计算机联接，这增加了成本和对使用

者的要求。而且电液比例阀容易被油液污染，维护不便。

高速开关数字阀（简称高速开关阀）除了具有结构简单、工作可靠、寿命长、

易于维修、抗污染能力强等特点，它还具有较高的响应速度，且重复误差小。特

别是高速开关阀可以直接采用计算机控制，无需 A/D、D/A 接口元件，也省去了

模拟量控制所要求的各环节间的线性和连续性，控制简单。但是受高速开关阀本

身结构的限制，其输出流量较小，因此，更适于作为先导控制阀的先导级元件。

所以本文将设计控制多路换向阀的先导用高速开关阀，以便于构建数字式控制比

例多路阀。

课题首先讨论了比例多路阀的结构、工作特性、控制原理及其在国内外的技

术发展水平，在此基础上分析了高速开关阀的结构、阀芯运动原理、工作特性和

液压控制回路形式，研究了脉宽调制（PWM）式高速开关阀控制的原理、特点及

所选多路阀的特点和技术参数，建立了高速开关阀控制多路阀的系统方案图。为

设计出与所选多路阀相匹配的高速开关阀，并具有较好的静动态特性，课题还研

究了高速开关阀的结构包括液压阀和电磁铁两部分，对其建立了数学模型，并通

过AMEsim 软件进行仿真，找出不同液压阀参数对其性能的影响。完成了液压阀

的关键尺寸的设计。在液压设备上进行了数字阀的空载特性试验、动静态特性试

验和多路阀的比例控制试验，验证了所设计高速开关阀结构的合理性，以及多路

阀的高速开关阀控制策略的合理性。

关键字：高速开关数字阀；数字式比例多路阀；PWM控制；空载特

性试验；动静态特性试验

ABSTRACT

The usage of electro-hydraulic proportional multiple directional valve (for short

proportional multiple directional valve) has grown obviously in the past ten years. It has

unusual advantage in function: meet with requirement of both electro-control and

manual-control on engineer equipment; it can be adjusted in proportional, which makes

the movement of the engineer machine controlled well; also, its load sensitive control

function makes the valve and the pump more Energy Efficiency. But, accompany with

the development of the Automation Technology, requirement of control accuracy,

response time, degree of automation on multiple valve becomes more and more strict.

Though, the electro-hydraulic proportional multiple valve can agree with this, it only

works in analog way, if the computer needs to be used in this control, the valve must be

connected with the computer by A/D, D/A convertor component, which leads higher

cost and requirement of operators/users. Also, the the electro-hydraulic proportional

multiple valve is easy to be polluted and hard to be maintained.

The high-speed on-off digital valve (for short the high-speed on-off valve) have

more simple structure, lower price, higher reliability, longer life cycle, easy to be

maintained, good performance on resisting pollution, and can work under some bad

condition etc.. Especially, it has higher response speed, little repetition error; can be

controlled by computer directly without linear and continuity required in each link of

analog single control, so the control becomes more simple. But, due to limitation of the

quick on-off digital valve’s structure, the normal flow is smaller, so, it is applied to

control the big power status as pilot valve. So, in this article, we’ll introduce how to use

quick on-off digital valve to control the multiple directional valve, then build a

proportional multiple directional valve by digital control mode.

Make the quick on-off digital valve as pilot step of the multiple valve and

controlled by computer directly, also, keep the hand knob/joy stick of the multiple valve.

This new digital proportional multiple directional valve has higher reliability, easy to be

maintained, lower cost, and easy to realize automation. Also, controlling the quick

on-off digital valve by PWM, then control the core of the multiple valve, this way not

only has all the advantages of computer control, but also cut down the work of system

design, and no dis-match among all the collection port, which makes the system more

reliable, and more powerful on interference proof capability.

This article is divided into five chapters for introduction. In the first chapter, we

mainly introduce the structure, the work characters, the control theory, and development

of the technology internal & overseas. The second part analysis the movement theory &

structure of the quick on-off digital valve core, the hydraulics control circuit and its

work characters, study the theory and advantage of the PWM quick on-off digital valve,

introduce the characters, the theory and technical parameters of the multiple valve

selected in this article, then build a hydraulics system of multiple valve controlled by

quick on-off digital valve. In the third part, we designed the quick on-off digital valve

applied to the multiple valve system selected. To enhance the response frequency of the

quick on-off digital valve, and cut down its response time, improve its property, we

studied the structure of the quick on-off digital valve, such as the core and the main

body etc., then build a mathematics mode, optimized the design of its main parameters,

such as the pressure drop, the max flow speed around the valve port, the movement

distance of the core, the normal dimension of the body port etc., found out several

groups of parameters based on the theory analysis, then simulated by AMESIM to find

out the different affection on its property caused by different parameters. Also, the

affection caused by fluid power and flow impaction were considered. In the fourth part,

the experiment/test on unload character and dynamics & static character were done

based on the mathematics simulation and optimization, also the rationality of the digital

valve is verified. The last part is the summary and the forecast of the whole article.

Key Word: High-speed on-off digital valve; Digital proportional

multiple valve; PWM control; Unload character test;

Dynamics & Static character test.

摘要 ........................................................................................................................... I

ABSTRACT ......................................................................................................................2

第一章绪论.....................................................................................................................1

§1.1 电液比例多路换向阀..........................................................................................1

§1.2 电液比例多路换向阀的国内外先进技术水平..................................................2

§1.3 课题的主要任务..................................................................................................3

§1.4 课题的意义..........................................................................................................4

第二章高速开关数字阀和多路换向阀特性研究.........................................................5

§2.1 高速开关数字阀..................................................................................................5

§2.1.1 高速开关数字阀的结构...............................................................................5

§2.1.2 高速开关数字阀的阀芯运动分析...............................................................6

§2.1.3 高速开关数字阀的特性分析.......................................................................9

§2.1.4 高速开关数字阀的液压控制回路形式.....................................................11

§2.2 脉宽调制方法的研究........................................................................................13

§2.2.1 脉宽调制（PWM）式高速开关阀控制及其工作原理 ........................... 13

§2.2.2 液压脉宽调制系统的优点.........................................................................15

§2.3 所用多路阀........................................................................................................15

§2.4 液压系统的建立................................................................................................17

§2.5 本章小结............................................................................................................17

第三章高速开关数字阀的研制和设计.......................................................................18

§3.1 高速开关阀的液压阀研制................................................................................18

§3.1.1 输出压力与输出流量.................................................................................18

§3.1.2 高速开关数字阀的结构参数.....................................................................23

§3.1.3 复位弹簧.....................................................................................................29

§3.1.4 液流对球阀的作用力.................................................................................32

§3.1.5 高速开关数字阀液压阀的设计.................................................................36

§3.1.6 高速开关数字阀液压阀的通断控制原理.................................................38

§3.2 高速开关数字阀电磁铁的设计.........................................................................40

§3.2.1 高速开关数字阀中的电磁技术理论.........................................................40

§3.2.2 高速开关数字阀中的电磁设计原则.........................................................43

§3.2.3 高速开关数字阀的电磁铁设计.................................................................47

§3.3 高速开关数字阀的整体构造图.........................................................................52

§3.4 本章小结.............................................................................................................54

第四章高速开关数字阀的特性测试和多路阀的比例控制实验...............................55

§4.1 实验装置.............................................................................................................55

§4.2.1 数字实验台.................................................................................................55

§4.1.2 数字阀实验阀块.........................................................................................57

§4.2 数字阀控制原理及控制器设计........................................................................58

§4.2.1 高速开关数字阀 PWM 控制原理 ............................................................. 58

§4.2.2 控制器设计.................................................................................................58

§4.3 数字阀特性测试.................................................................................................61

§4.3.1 高速开关数字阀的空载测试.....................................................................61

§4.3.2 高速开关数字阀的静态实验.....................................................................65

§4.3.3 高速开关数字阀的动态实验.....................................................................73

§4.4 比例控制实验....................................................................................................75

§4.4.1 实验原理.....................................................................................................75

§4.4.2 实验结果及分析.........................................................................................76

§4.5 本章小结............................................................................................................77

第五章总结与展望.......................................................................................................79

§5.1 工作总结............................................................................................................79

§5.2 全文展望............................................................................................................80

参考文献.........................................................................................................................81

在读期间公开发表的论文和承担科研项目及取得成果.............................................84

致谢.................................................................................................................................85

第一章绪论

§1.1 电液比例多路换向阀

多路换向阀简称多路阀，是由两个以上的换向阀为主体，集换向阀、主安全

阀、过载阀、单向阀、分流阀、补油阀、制动阀等于一体的多功能集成阀，能够

满足不同液压系统的要求[1-2]。又因多路阀具有结构紧凑、压力损失小、管路简单

和安装简便等优点，使它在工程机械领域得到了广泛地应用[3]。工程机械（特别是

自行式）的工作机构多是共有的特点，能够实现多种功能。且这些工作机构的动

作有许多是由液压方式驱动的，一般不要求他们全部同时动作，因此常常出现多

个工作机构公用一个或两个泵源的情况。利用多路阀实现对这些工作机构的控制，

不仅减少了连接管路和流阻的损失，提高了工作可靠性，也大大降低了操作人员

的工作强度。但随着自动化时代的到来，现代工程机械要求多路阀具有电控与手

动二种功能同时存在、能够比例调节、运动过程受控等特性，一般的多路阀已不

能满足，此时就必须使用电液比例多路换向阀才能达到。

电液比例多路换向阀由信号给定装置、电控器、先导减压阀和主阀四部分组

成，如图1-1所示。

图1-1 电液比例多路阀

主阀和先导减压阀之间以先导定压——主阀弹簧定位的方式耦连。即由先导

级输出控制压力，在主阀芯端面上产生一个液压力，克服主阀弹簧力，推动主阀

芯移动。当主阀芯上诸力达到平衡时，主阁芯停留在和先导控制压力相对应的位

置上，从而实现了先导阀对主阀芯轴向位移的比倒控制[4-8]。利用先导阀非线性的

输入输出特性，扩大了电液比例多路阀的比例操作范围，消除了操作死区。图1-2

是电液比例多路阀的一个应用实例。

多路阀的比例控制，是先导阀接受模拟或数字式信号，控制出口油液的压力

和流量，驱使主阀芯与输入量成比例地移动，改变节流口截面积，从而控制多路

阀输出流量。若对主阀芯实施位置监控，还可提高多路阀的控制精度。这个过程

的控制框图如图 1-2 所示。

信号给定装

多路电控

先导减压

主

阀

先导减压

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摘要：

摘要电液比例多路换向阀（简称比例多路阀）的应用在近十多年来有明显的增长。它在功能上有下列不可取代的优点：满足工程机械使用上电控与手动二种功能同时存在的要求；具有比例调节的功能，满足许多工程机械上运动过程受控的要求；采用负载敏感技术，满足阀控或泵控的节能要求。但随着自动化技术的发展，对多路阀的控制精度、响应速度、自动化程度等性能有了更高的要求。虽然比例阀先导控制的多路阀能满足要求，但比例阀构成的模拟式比例控制，如果要求计算机控制，还必须通过A/D、D/A接口元件与计算机联接，这增加了成本和对使用者的要求。而且电液比例阀容易被油液污染，维护不便。高速开关数字阀（简称高速开关阀）除了具有结构简单、工...

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