CN202149270U

CN202149270U - Intelligent positioning module based on network control

Info

Publication number: CN202149270U
Application number: CN201020586756U
Authority: CN
Inventors: 石小江; 陈洪敏; 张中光; 罗乘川
Original assignee: China Gas Turbine Research Institute
Current assignee: China Gas Turbine Research Institute
Priority date: 2010-11-02
Filing date: 2010-11-02
Publication date: 2012-02-22
Anticipated expiration: 2020-11-02

Abstract

The utility model relates to an intelligent positioning module based on network control, which is used for an electric actuator. The intelligent positioning module based on network control is provided with an Aduc832 chip and peripherals such as a position detector, an external signal input, a motor drive, a human-machine interface, a network interface and the like, wherein a program storage is arranged in the Aduc832 chip which is integrated with an IO (Input/Output) module, a D/A (Digital-to-Analogue) module, an A/D (Analogue-to-Digital) module, a parallel port and a serial port. The intelligent positioning module based on network control has the MODBUS network protocol, has a built-in PID (Proportion Integration Differentiation) regulation function, can input control information to any electric actuator in the network by the RS485 network and can return corresponding information after control by the network, while the controlled variable can be not only a position signal but also pressure, temperature and the like. In addition, parameters can also be modified on site through a keyboard and a liquid crystal display.

Description

A kind of intelligent locating module of control Network Based

Technical field

The utility model relates to industry, and the valve electric actuator of chemical field is particularly about the intelligent locating module in the YE.

Background technique

The core component part that this intelligence locating module is a YE.YE is meant that in control system with a kind of final controlling element of electricity as the energy, it accepts the electrical signal of regulation meter, becomes the angular displacement or the rectilinear path displacement of output shaft to it, and actuator---valve event is carried out the adjusting task to promote to regulate.The intelligent positioner module is installed on YE inside; Accept 0～10mA of regulator or the standard dc current signal of 4～20mA; With from the interior location signal of sensor; Through the logic control mode that defines in advance, change corresponding logic electrical signal into, actuator---the normally unidirectional or three phase alternating current motor in the control YE.

Locating module is made up of analogue amplifier, ad/da converter and microprocessor usually.Can be divided into integral type and proportion expression by control logic.Proportion expression commonly sees also Fig. 1 in the market, and it is a kind of fundamental diagram of proportion expression locating module.By the position feed back signal of direct current (d.c.) input signal of the 0～10mA that regulates or 4～20mA with position transducer after subtracting; Its error signal is amplified the rear driving motor through servoamplifier and is rotated; Export an angular displacement or straight journey displacement through being positioned at after the inner retarder of final controlling element slows down, drive controlling mechanism and regulate.The inner position transducer of final controlling element changes the carry-out bit transfer into corresponding direct-flow output signal as position feed back signal simultaneously; Deliver to the servoamplifier input end; It changes along with the size of output displacement; When the difference of Displacement Feedback signal and input signal equalled zero, motor stopped operating, and actuator is stabilized on certain position.

Most of locating module in the market adopts the proportion expression control logic usually, input 4～20mA control signal, output 4～20mA analog position signal.A lot of locating modules are arranged on the market at home, but basically do not possess network connecting function, its complex structure, less reliable, cost is high.

Summary of the invention

The purpose of the utility model: in order to reduce controlling cost and the diversified problem of control target of many YEs; The utility model provides the intelligent locating module of a kind of MODBUS of having network protocol and internal PID regulatory function, can be through the RS485 network to being in any YE input control information in the network; And return the corresponding information after control is accomplished through network; Controlled volume is not only a position signal, also can be pressure, temperature etc.

The technological scheme of the utility model: in order to solve the problems of the technologies described above; The detailed technology scheme of the utility model is following: a kind of intelligent locating module of control Network Based; It has the Aduc832 chip that an inside has program storage; And said Aduc832 chip is integrated with IO module, D/A module, A/D module, LPT and serial port; Wherein, said Aduc832 chip LPT is connected with LCD display and keyboard, and said Aduc832 chip serial port drives with RS485 through an optoelectronic isolator and links to each other; The IO module of said Aduc832 chip links to each other with the control motor through an optoelectronic isolator and motor driving; Simultaneously, this IO module is connected with an isolating switch through another optoelectronic isolator, and said D/A module directly links to each other with adjustable 4～20mA output and links to each other with 4～20mA output through the V/I transducer; Said adjustable 4～20mA output links to each other with the A/D module through signal conditioner, and said A/D module links to each other with the transmitter of 4～20mA external control signal and 4～20mA through two I/V transducers respectively.

Said IO module, D/A module, A/D module, LPT and serial port have RS485 bus physical communication interface, support the MODBUS network communication protocol, and are connected with master controller in the network, constitute a control network jointly.

Master controller is a computer in the said network.

Said Aduc832 chip is embedded with the displacement that not only can control actuator in the YE, and can control the PID mathematical algorithm of the relevant parameter such as pressure, flow, temperature of fluid.

The intelligent locating module of described control Network Based is provided with the current metering sensor of the current parameters that can keep watch on actuator.

The beneficial effect of the utility model: the intelligent locating module of the utility model control Network Based through the RS485 network to being in any YE input control information in the network; And return the corresponding information after control is accomplished through network; Make electric valve actuator in application, become simpler; Cost is lower, and automaticity is higher, and reliability is higher.Simultaneously, this actuator has carried the PID controller, can realize outside one-parameter control, for the user has practiced thrift regulation meter.The liquid crystal screen display operation state and the relevant parameter of valve when moving instantly, easy-to-operat personnel effectively monitor operation.

Description of drawings

Fig. 1 is a kind of fundamental diagram of existing technology proportion expression locating module;

Fig. 2 is the structured flowchart of intelligent locating module one preferred embodiments of the utility model control Network Based;

Fig. 3 is the utility model motor driving and current detection circuit figure;

Fig. 4 is the utility model RS485 communication circuit figure;

Fig. 5 is the fundamental diagram of the intelligent locating module of the utility model control Network Based;

Fig. 6 is the main flow chart of the intelligent locating module of the utility model control Network Based

Fig. 7 is that the utility model is for MODBUS agreement support process figure;

Fig. 8 is the utility model control flow chart;

Fig. 9 is the utility model electric motor protecting flow chart.

Embodiment:

Through embodiment the utility model is done further to specify below:

See also Fig. 2, it is the structured flowchart of intelligent locating module one preferred embodiments of the utility model control Network Based.Said intelligent locating module is a core with the Aduc832 chip of Analog Device company, and is equipped with position probing, external signal input, motor driving, peripheral unit such as man-machine interface and network interface.Wherein, said ADUC832 chip is a multi-functional embedded central processing unit (CPU) chip that has modulus and digital-to-analog conversion function, and inside has program storage, can move corresponding task according to the program that the user writes.This Aduc832 chip is integrated with IO module, D/A module, A/D module, LPT and serial port.Said Aduc832 chip LPT is connected with LCD display and keyboard, is respectively applied for the input and the modification of image demonstration and parameter.Said Aduc832 chip serial port drives with RS485 through an optoelectronic isolator and links to each other.The IO module of said Aduc832 chip links to each other with the control motor through an optoelectronic isolator and motor driving.Simultaneously, this IO module is connected with an isolating switch through another optoelectronic isolator.Said D/A module directly links to each other with adjustable 4～20mA output and links to each other with 4～20mA output through the V/I transducer.Said adjustable 4～20mA output links to each other with the A/D module through signal conditioner.And said A/D module links to each other with the transmitter of 4～20mA external control signal and 4～20mA through two I/V transducers respectively.

The utility model intelligence locating module is the center with the ADUC832 chip, and the next design of software of carrying out peripheral interlock circuit and internal operation realizes network control function simply and easily.Fig. 6 is the main program flow chart of said intelligent locating module, and its running is following, and advanced A/D translation data is gathered; Through the communication of MODBUS protocol network, carry out data processing according to the liquid crystal display displays data by keyboard more then, export the current executed mechanism position then; Acceptance is from the networking command of RS485; After controlling the position of YE or passing through the PID computing, control reaches setting value from the fluid parameter of transmitter, the actuator of operation band protective function.Wherein, on LCD, show current valve position, valve state and fluid parameter value, system realizes the full scale and the automatic adjustment at zero point through A/D module and D/A module.Keyboard is used for the input and the modification of parameter, in addition, also can control through traditional 4～20mA analogue signal.

The utility model intelligence locating module has network control function, adopts the MODBUS communication protocol based on the RS485 bus, and the detailed content of this communication protocol please refer to GB GB/T 19582-2008.The serial-port communication peripheral hardware of ADUC832 chip can not satisfy RS485 bus physical electric characteristic, does not support RS485 bus communication networking.The peripheral circuit of the utility model through designing voluntarily, as shown in Figure 4, make this module on electrical characteristic, support the RS485 bus network.And for the support of MODBUS agreement, its routine processes flow process is as shown in Figure 7, after promptly beginning; Whether the reception value is satisfied minimal condition judge (minimum 8 characters),, then discern MODBUS protocol function sign indicating number if satisfy minimal condition; If do not satisfy minimal condition, then direct end loop; If can discern MODBUS protocol function sign indicating number, then judgement receives the minimum number whether character number satisfies this function code defined, should circulate if do not satisfy then directly finish, if satisfy, judges then whether information is effective; If information is invalid, then return error message and end loop, if information is effective, then carries out correlation function and handle, and return confirmation, thereby accomplish a duty cycle.

The utility model intelligence locating module both can be controlled the target valve aperture through the program in the ADUC832 chip, can realize the control for on-site target parameter (like pressure, temperature, flow) again.Figure is as shown in Figure 5 for its control principle, utilizes present widely used proportional control algorithm and PID algorithm (being pid algorithm) to realize that its control program is as shown in Figure 8.In this mode of execution; To convert digital signal to from the isoparametric current signal of expression pressure, temperature of transmitter; With comparing from the control signal of keyboard setting, RS485 bus network or common 4～20mA, carrying out computing through pid algorithm, the inner motor of control YE just changes, reverses or stops; Thereby control reaches automatic control hydrodynamic pressure, the isoparametric effect of flow with the aperture of the angular travel valve of YE connection.Wherein, the flow chart that pid algorithm is realized is as shown in Figure 9, after promptly beginning, through 4～20mA signal or keyboard or network, selects the input source of given parameter; Judge whether to select valve position as Control Parameter, if not, a program cycle accomplished through pid control algorithm, if the passing ratio control algorithm is accomplished a duty cycle.

When the actuator in the YE (being generally the one-way communication motor) for a certain reason after the stall, the current effective value through YE will substantially exceed the scope that actuator can bear.The utility model intelligence locating module has increased a current measurement circuit for this reason, and is as shown in Figure 3, measures the electric current that flows through actuator.And set a protection value in the software of said intelligent locating module operation, electric current surpasses after the normal value certain hour, stops actuator's action, thereby plays a protective role.Its protection handling process is following, after the beginning, judges whether actuator transships earlier, if not, then normally operation until accomplishing circulation, if be in overload, then stops actuator; Judge again whether setting value changes,, then accomplish a duty cycle, if variation has taken place setting value, then withdraw from overload, and accomplish a duty cycle if do not change.

The technical order of the intelligent locating module of this mode of execution is as shown in table 1:

Operating voltage	?220VAC
		Operating temperature	?0～60°
Continuous time between failures	?168h
		Location accuracy	?0.3％
The maximum AM access module numbers of network	?256

The technical order of the intelligent locating module of table 1

The intelligent locating module of the utility model control Network Based is a core with the Aduc832 chip of Analog Device company; And link position detects; The external signal input; Motor driving, peripheral unit such as man-machine interface and network interface download software in the ADUC832 chip through programmable device again.In this mode of execution; Networking mode between disparate modules can be with reference to the RS485 bus connecting mode; In bus network, connect a PC who supports RS485 communication; Through the MODBUS agreement control software that moves among this PC, just disparate modules in the may command network moves thereby control a plurality of YEs.After powering on for the first time, adjust the parameter of software inhouse, can normally move through keyboard or network.

The locating module of the utility model control Network Based can be through selecting three kinds of input modes such as 4～20mA, network, keyboards in sum; Adopt MODBUS communication protocol, can realize being connected with configuration software; Can realize regulating and parameter modification through PID; But also can realize that unperturbed manual, control automatically switches, and makes that simultaneously actuator has high orientation precision.Realized that many electric valve actuators use the work of a computer through on-the-spot each valve of network-bus control simultaneously, made control simpler, practiced thrift the control connection line, hardware facilities such as computer.

Claims

1. the intelligent locating module of a control Network Based; It is characterized in that: have the Aduc832 chip that an inside has program storage; And said Aduc832 chip is integrated with IO module, D/A module, A/D module, LPT and serial port; Wherein, said Aduc832 chip LPT is connected with LCD display and keyboard, and said Aduc832 chip serial port drives with RS485 through an optoelectronic isolator and links to each other; The IO module of said Aduc832 chip links to each other with the control motor through an optoelectronic isolator and motor driving; Simultaneously, this IO module is connected with an isolating switch through another optoelectronic isolator, and said D/A module directly links to each other with adjustable 4～20mA output and links to each other with 4～20mA output through the V/I transducer; Said adjustable 4～20mA output links to each other with the A/D module through signal conditioner, and said A/D module links to each other with the transmitter of 4～20mA external control signal and 4～20mA through two I/V transducers respectively.

2. the intelligent locating module of control Network Based according to claim 1; It is characterized in that: said IO module, D/A module, A/D module, LPT and serial port have RS485 bus physical communication interface; Support the MODBUS network communication protocol; And be connected with master controller in the network, constitute a control network jointly.

3. the intelligent locating module of control Network Based according to claim 2, it is characterized in that: master controller is a computer in the said network.

4. the intelligent locating module of control Network Based according to claim 3 is characterized in that: the current metering sensor that is provided with the current parameters that can keep watch on actuator.