调节阀智能阀门定位器控制系统的研制
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摘要
生产过程的自动控制简称过程控制，它在工业生产中占有极其重要的地位。过程控制的质量很大程度上决定于过程控制仪表，它包括变送器、调节器、执行器以及各种辅助控制装置。本文讨论的一种辅助控制仪表——阀门定位器，是各国竞相研究的对象，它在一定程度上决定了过程控制的调节品质，且随着过程控制水平的发展，定位器也必须不断发展以满足现代生产对过程控制的要求。目前定位器的研究热点主要在于智能阀门定位器，国外一些大公司，如西门子、费希尔-罗斯蒙特等，已相继有产品推出，国内这方面起步较晚。国内目前普遍使用的电气阀门定位器采用的是机械式力平衡原理，存在一些不足且不能满足过程控制发展的需要，而由国外进口的智能型定位器价格昂贵，因此研究设计智能型电气阀门定位器是十分必要的。
智能阀门定位器集合了机械、电子、通讯以及控制理论知识和相关软件知识，是一个跨学科的智能产品。本课题研制的主要对象是智能阀门定位器的控制系统，它通过采集从调节器来的设定阀门开度信号和反馈回来的实际阀门开度信号，在经过偏差与偏差变化率的计算后，通过模糊运算与决策输出相应的控制信号去控制压电阀的开启时间，从而控制进入调节阀气室的进气量，以此推动阀芯动作并准确定位。这样，相对传统阀门定位器，该智能阀门定位器不仅体现出精度提高，能耗降低，功能增多等优点，而且它能集合一定人类的经验知识，具有一定的思维能力，符合过程控制的发展需要。
本课题主要完成以下内容：
(1)深入了解传统阀门定位器的结构，工作原理，分析传统定位器的主要不足，跟踪国外智能阀门定位器的发展情况。
摘要
(2)对智能阀门定位器的控制系统进行总体设计，对系统中的各个芯片进
行选材。
(3)在系统的控制策略方面，将模糊控制技术应用到系统中，使系统不仅
不需要建立被控对象完整精确的数学模型，而且能够使系统根据人们的经验
知识作出相应的决策。同时使得本系统具有良好的“鲁棒性”和自诊断性。
(4)对从调节器送来的4一20mA电流信号进行I瓜转换，同时对转换后的
信号进行A/D转换;对经电位器反馈回来的阀位信号进行刀D转换。在单片
机中对以上两路信号进行标度变换以及BCD码的转换，以便于在显示板上进
行十进制数的显示。
(5)对系统的后向通道进行设计与制作。使单片机输出的微弱的控制信号
能够通过固态继电器控制压电阀的开启，以最终控制进入调节阀气室的进气
正三日
~与邑。
(6)对系统的键盘、显示电路进行设计和制作。
(7)对系统进行数据的断电保护功能设计，使重要参数在断电时能得以保
存，同时在来电时，重要参数能得以自动恢复;对系统进行看门狗功能的设
计。
(8)对单片机输出的TTL电平信号进行RS一232标准的转换，使单片机控
制系统能与上位机进行串口通讯。对单片机控制系统传送的数据进行ASCn
码转换，以便于上位机的接收与识别。
(9)对复位电路、报警等电路进行设计、制作。
(10)对整个控制系统进行程序编写，以实现控制系统的各个功能和实现
控制系统的控制策略。单片机控制系统的程序采用汇编语言编写，软件中的
数据采用定点数形式。上位机的串口通信程序使用VC十+6 .0进行开发，并通
过ActiveX控件—MSComm通信控件来实现数据传输。
通过实验证明，该方案是可行的。与常规定位器相比，该定位器具有控
制精度高、能耗低、调整方便，适用范围广、能任意选择调节阀的流量特性
等特点，同时该定位器具有一定思维能力，以及阀位显示和故障报警，与PC
机进行串口通信等功能。
The abbreviation of the automatic control of manufacture process is process control, it is of great importance in the industry. In the great degree, the quality of process control is decided by the instrumentations of process control that include transmitters, controllers, actuator and various assistant control devices. The text discusses the valve positioner, a kind of assistant control device, it is contested to research in every country. The positioner decides the quality of process control in some degree, and with the development of the standard of process control, it must be developed to meet the reqirement of modern manufacture to the process control. Now the research's hotspot of positioner focuses on the intellective valve positioner. Some foreign companies, such as Siemens, Fisher-Rosemont etc, have orderly developed the intellective valve positioner, but in our country the research in this field is begun late. Now the electropneumatic valve positioners used generally in our country adopts the force
-balanced-type, which had some disadvantages and can't meet the demand of the process contr. However the import intellective valve positioners are very expensive, so the research of the intellective valve positioner is very necessary.
Mechanism, electronics, communication, the knowledge of the control theory and the knowledge of relative software are applied in intelligent valve positioner, so it is a intelligent product of muti-subject. The main object researched by this thesis is control system of Single Chip Microcomputer, it send out signal to control
piezoelectricity valve after collecting the designed signal of the valve position from the adjuster and the real signal of the valve position from feedback, and fuzzily dealing with this two signals, so that it can control the quantity of gas which is injected into the gas chamber in the control valve, which make the valve stem work and make it attain accurate position. Comparing with traditional valve positioner, the intelligent valve positioner has the advantages of excellent controlling accuracy, low energy consuption and more functions, and it meet the demand of process control with its function of thinking and possessing some experience and knowledge of man. This research has mainly accomplished the content as followings:
(1) Learn deeply about the configuration and working principle of traditional valve positioner, analyse the main disadvantages of traditional valve positioner and learn about the developing situation of the foreign intelligent valve positioner.
(2) Design wholly the control system of the intelligent valve positioner, choose the right chip which is in the control system.
(3) As for controlling strategy of the system, the fuzzy control is applied in the this system. So it is not necessary to be built the whole and accurate mathematic model for the system, and the system can make a decision according to people's experience and knowledge. At the same time, the system possesses good robustness and self-diagnose function.
(4) Make I/V transform for the current signal of 4~20mA coming from adjustor, then make A/D transform for the signal received just now. Make A/D transform for the signal delegating valve position, which is feed backed from the potentiometer ?
(5) Design and manufacture the back passage of the system, which make Single Chip Microcomputer send out faint controlling signal to control the on/off of piezoelectricity valve through Solid State Relay. As a result, it can control the quantity of gas which is injected into the gas chamber in the control valve.
(6) Design and manufacture the key and showing circuit of the system.
(7) Design the function of protecting data when no power, which can protect the important data when power is off, and send the protected data into the Single Chip Microcomputer when the power is on.
(8) Make a transform from TTL signal sent out from Single Chip Microcomputer to RS-232, which can make the control system of Single Chip Microcomputer communicating with PC.
(9) Desig
智能阀门定位器集合了机械、电子、通讯以及控制理论知识和相关软件知识，是一个跨学科的智能产品。本课题研制的主要对象是智能阀门定位器的控制系统，它通过采集从调节器来的设定阀门开度信号和反馈回来的实际阀门开度信号，在经过偏差与偏差变化率的计算后，通过模糊运算与决策输出相应的控制信号去控制压电阀的开启时间，从而控制进入调节阀气室的进气量，以此推动阀芯动作并准确定位。这样，相对传统阀门定位器，该智能阀门定位器不仅体现出精度提高，能耗降低，功能增多等优点，而且它能集合一定人类的经验知识，具有一定的思维能力，符合过程控制的发展需要。
本课题主要完成以下内容：
(1)深入了解传统阀门定位器的结构，工作原理，分析传统定位器的主要不足，跟踪国外智能阀门定位器的发展情况。
摘要
(2)对智能阀门定位器的控制系统进行总体设计，对系统中的各个芯片进
行选材。
(3)在系统的控制策略方面，将模糊控制技术应用到系统中，使系统不仅
不需要建立被控对象完整精确的数学模型，而且能够使系统根据人们的经验
知识作出相应的决策。同时使得本系统具有良好的“鲁棒性”和自诊断性。
(4)对从调节器送来的4一20mA电流信号进行I瓜转换，同时对转换后的
信号进行A/D转换;对经电位器反馈回来的阀位信号进行刀D转换。在单片
机中对以上两路信号进行标度变换以及BCD码的转换，以便于在显示板上进
行十进制数的显示。
(5)对系统的后向通道进行设计与制作。使单片机输出的微弱的控制信号
能够通过固态继电器控制压电阀的开启，以最终控制进入调节阀气室的进气
正三日
~与邑。
(6)对系统的键盘、显示电路进行设计和制作。
(7)对系统进行数据的断电保护功能设计，使重要参数在断电时能得以保
存，同时在来电时，重要参数能得以自动恢复;对系统进行看门狗功能的设
计。
(8)对单片机输出的TTL电平信号进行RS一232标准的转换，使单片机控
制系统能与上位机进行串口通讯。对单片机控制系统传送的数据进行ASCn
码转换，以便于上位机的接收与识别。
(9)对复位电路、报警等电路进行设计、制作。
(10)对整个控制系统进行程序编写，以实现控制系统的各个功能和实现
控制系统的控制策略。单片机控制系统的程序采用汇编语言编写，软件中的
数据采用定点数形式。上位机的串口通信程序使用VC十+6 .0进行开发，并通
过ActiveX控件—MSComm通信控件来实现数据传输。
通过实验证明，该方案是可行的。与常规定位器相比，该定位器具有控
制精度高、能耗低、调整方便，适用范围广、能任意选择调节阀的流量特性
等特点，同时该定位器具有一定思维能力，以及阀位显示和故障报警，与PC
机进行串口通信等功能。
The abbreviation of the automatic control of manufacture process is process control, it is of great importance in the industry. In the great degree, the quality of process control is decided by the instrumentations of process control that include transmitters, controllers, actuator and various assistant control devices. The text discusses the valve positioner, a kind of assistant control device, it is contested to research in every country. The positioner decides the quality of process control in some degree, and with the development of the standard of process control, it must be developed to meet the reqirement of modern manufacture to the process control. Now the research's hotspot of positioner focuses on the intellective valve positioner. Some foreign companies, such as Siemens, Fisher-Rosemont etc, have orderly developed the intellective valve positioner, but in our country the research in this field is begun late. Now the electropneumatic valve positioners used generally in our country adopts the force
-balanced-type, which had some disadvantages and can't meet the demand of the process contr. However the import intellective valve positioners are very expensive, so the research of the intellective valve positioner is very necessary.
Mechanism, electronics, communication, the knowledge of the control theory and the knowledge of relative software are applied in intelligent valve positioner, so it is a intelligent product of muti-subject. The main object researched by this thesis is control system of Single Chip Microcomputer, it send out signal to control
piezoelectricity valve after collecting the designed signal of the valve position from the adjuster and the real signal of the valve position from feedback, and fuzzily dealing with this two signals, so that it can control the quantity of gas which is injected into the gas chamber in the control valve, which make the valve stem work and make it attain accurate position. Comparing with traditional valve positioner, the intelligent valve positioner has the advantages of excellent controlling accuracy, low energy consuption and more functions, and it meet the demand of process control with its function of thinking and possessing some experience and knowledge of man. This research has mainly accomplished the content as followings:
(1) Learn deeply about the configuration and working principle of traditional valve positioner, analyse the main disadvantages of traditional valve positioner and learn about the developing situation of the foreign intelligent valve positioner.
(2) Design wholly the control system of the intelligent valve positioner, choose the right chip which is in the control system.
(3) As for controlling strategy of the system, the fuzzy control is applied in the this system. So it is not necessary to be built the whole and accurate mathematic model for the system, and the system can make a decision according to people's experience and knowledge. At the same time, the system possesses good robustness and self-diagnose function.
(4) Make I/V transform for the current signal of 4~20mA coming from adjustor, then make A/D transform for the signal received just now. Make A/D transform for the signal delegating valve position, which is feed backed from the potentiometer ?
(5) Design and manufacture the back passage of the system, which make Single Chip Microcomputer send out faint controlling signal to control the on/off of piezoelectricity valve through Solid State Relay. As a result, it can control the quantity of gas which is injected into the gas chamber in the control valve.
(6) Design and manufacture the key and showing circuit of the system.
(7) Design the function of protecting data when no power, which can protect the important data when power is off, and send the protected data into the Single Chip Microcomputer when the power is on.
(8) Make a transform from TTL signal sent out from Single Chip Microcomputer to RS-232, which can make the control system of Single Chip Microcomputer communicating with PC.
(9) Desig
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2 明锡东．调节阀计算、选型、使用．成都：成都科技大学出版社，1999
3 吴国熙．调节阀使用与维修．北京：化学工业出版社，1999
4 向婉成．过程控制调节装置．北京：机械工业出版社，1999
5 孙自强．生产过程自动化及仪表．华东理工大学出版社，1999
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