CN207529214U

CN207529214U - A kind of rotation speed measuring module for DCS system

Info

Publication number: CN207529214U
Application number: CN201721438710.8U
Authority: CN
Inventors: 梁超宇; 蒋杰; 王维建
Original assignee: SHANGHAI XINHUA CONTROL TECHNOLOGY (GROUP) Co Ltd
Current assignee: SHANGHAI XINHUA CONTROL TECHNOLOGY (GROUP) Co Ltd
Priority date: 2017-11-01
Filing date: 2017-11-01
Publication date: 2018-06-22
Anticipated expiration: 2027-11-01

Abstract

The utility model discloses a kind of rotation speed measuring module for DCS system, including detection circuit and sample-taking calculating circuit two large divisions.Detection circuit realizes the preprocessing function of signal, is provided for FPGA and stablizes clean signal.Realize that FPGA realizes the accurate metering C of tacho-pulse and timing T, and microcontroller reads the C values cached in FPGA and T values, and completes the accurate calculating of rotating speed in a manner that programmable logic device FPGA and Chip Microcomputer A RM are combined in sample-taking calculating circuit part.And 3 rotating speed input channels can be included, can realize that the data of 3 channels are carried out at the same time measurement, improve the response speed of measurement in this way.Chip Microcomputer A RM realizes the calculating of rotating speed and the control of strategy simultaneously.When the speed of measurement object is more than setting value, with reference to On-off signal signal and analog input signal, protection signal is sent out after being calculated by microcontroller according to control strategy, fast response time is feature-rich.

Description

A kind of rotation speed measuring module for DCS system

Technical field

The utility model is related to the tachometric survey moulds in a kind of rotation speed measuring module more particularly to a kind of DCS control systems Block can realize the accurate measurement to tach signal and the accurate control to rotating speed.

Background technology

At present, scattered control system (Distributed Control System, abbreviation DCS) is widely used in industrial neck Domain, DCS are a multi-level computer systems using communication network as tie being made of process control level and process monitoring level, Basic thought is decentralised control, centralized operation, differentiated control, configuration is flexible, configuration is convenient.It is mainly characterized by high reliability, opens Putting property, control function are enriched.Quickly, reliable, high-precision tachometric survey and its velocity-measuring system are an important sets of this system Into part.

, it can be achieved that steam turbine etc. needs to measure in the device of rotating speed and overspeed protection in system application.It can extensive use In the production process of the industrial enterprises such as electric power, oil, chemical industry, metallurgy, environmental protection, accomplish to turn speed real-time measurement, fast response time is surveyed Accuracy of measurement is high, provides safeguard for production process safety stable operation.

The utility model can be used for measuring the occasion of other pulsed quantities, play an important role in modern industrial production.

But in the prior art, the measurement of tach signal is mainly measured by the CPU methods for being averaging speed, that is, In regular time T, the pulse of velocity sensor is counted, then calculates tachometer value using formula V=C/T.

But a series of problem can be caused in this way：

The timing time T of computer may be bothered and inaccurate by other processes；

The umber of pulse C of calculating timing time T to that time be possible to not be integer pulse.

The tachometer value calculated in this way using formula there is deviation.

In addition, in the prior art, the measurement of tach signal is mostly single channel tachometric survey, can not realize multichannel rotating speed It measures.

In the prior art simultaneously, rotation speed measuring module only has the function of measuring rotating speed, and function is relatively simple, if real The logic control of existing over-speed protection function and unbalanced power then needs the cooperation of other types fastener to complete entire logic control Function, system complex, reliability and accuracy be not high.

Therefore, those skilled in the art is dedicated to developing a kind of simple system, and functional diversities can collect tachometric survey It is integrated with rotating speed defencive function, can realize tachometric survey and the control system of multichannel tachometric survey and control.This reality Such design, which is based on, with novel inventor has developed a kind of new rotation speed measuring module.

Utility model content

In view of the drawbacks described above of the prior art, technical problem to be solved in the utility model is：

(1) corresponding speed measured is improved, improves the antijamming capability of measuring circuit, promotes the accurate of tachometric survey calculating Property；

(2) measurement of multichannel rotating speed is realized；

(3) it realizes the integrated of tachometric survey and overspeed protection and unbalanced power defencive function, uses single module Realize multiple functions；

(4) system forms simple, dependable performance, and real-time and precision are high, meets industry spot requirement.

To achieve the above object, the utility model provides a kind of rotation speed measuring module for DCS system, including detection Circuit and sample-taking calculating circuit, wherein the sample-taking calculating circuit further includes programmable logic chip FPGA and microcontroller, it is described Detection circuit provides signal, the microcontroller and institute for being pre-processed to signal for the programmable logic chip FPGA State programmable logic chip FPGA communication connections, wherein the programmable logic chip FPGA be used for the counting of tacho-pulse and Timing, obtains count value C and clocking value T, and the microcontroller is used to read the C values cached in the programmable logic chip FPGA With T values, rotating speed is calculated.

The utility model has creatively been used to be realized based on programmable logic chip FPGA and High Performance SCM ARM High-precision tachometric survey.This detection scheme, dependable performance, real-time and precision are high, meet industry spot requirement.

In the better embodiment of the utility model, the rotation speed measuring module for DCS system further includes and institute State the input channel and/or output channel of programmable logic chip FPGA connections.

The input channel includes tachometric survey channel, On-off signal channel and analog input channel.

The tachometric survey channel is 3 tunnels, and the On-off signal channel is 6 tunnels, and the analog input channel is 6 Road.

The output channel includes output switch parameter channel.

The output switch parameter channel is 3 tunnels.

The tachometric survey channel, On-off signal channel and analog input channel are used inside and outside optocoupler EL357N realizations Partial circuit is isolated.

The analog input channel in turn samples 6 road signals by the way of switching, and sampling A/D chip is ADS8320E。

In another better embodiment of the utility model, in the sampling A/D chip and the programmable logic chip Isolating chip is further included between FPGA, the isolating chip is ADuM1201 high speed magnetic medium isolating chips.

In another better embodiment of the utility model, the microcontroller is the high-performance ARM chips of 32, model MB9BF618S。

Therefore the rotation speed measuring module of the utility model includes detection circuit and sample-taking calculating circuit two large divisions.Detection electricity The preprocessing function of signal is realized on road, is improved the antijamming capability of circuit, is provided for FPGA and stablize clean signal.Sampling calculates Circuit part realizes that FPGA realizes tacho-pulse in a manner that programmable logic device FPGA and Chip Microcomputer A RM are combined Accurate metering C and timing T, microcontroller reads the C values cached in FPGA and T values, and completes the accurate calculating of rotating speed.

Due to completing tachometric survey using double mechanism.First, the measurement of tach signal is completed by FPGA, it can be with It realizes that the data of 3 channels are carried out at the same time measurement, improves the response speed of measurement in this way.Chip Microcomputer A RM realizes rotating speed simultaneously Calculating and strategy control.

The utility model can also realize that over-speed protection function and unbalanced power calculate defencive function, when measurement object When speed is more than setting value, with reference to On-off signal signal and analog input signal, calculated by microcontroller according to control strategy After send out protection signal, fast response time is feature-rich, and single module can complete multiple functions, easy to use.

The technique effect of the design of the utility model, concrete structure and generation is made furtherly below with reference to attached drawing It is bright, to be fully understood from the purpose of this utility model, feature and effect.

Description of the drawings

Fig. 1 is the measurement schematic block diagram realized according to the prior art；

Fig. 2 is the detailed embodiment block diagram of the present invention.

Specific embodiment

As shown in Figure 1, rotation speed measuring module includes detection circuit and sample-taking calculating circuit two large divisions.Detection circuit is realized The preprocessing function of signal improves the antijamming capability of circuit, is provided for FPGA and stablizes clean signal.Sample-taking calculating circuit portion Divide and realized in a manner that programmable logic device FPGA and Chip Microcomputer A RM are combined, FPGA realizes the accurate meter of tacho-pulse Number C and timing T, microcontroller reads the C values cached in FPGA and T values, and completes the accurate calculating of rotating speed.This module design has 3 Road tachometric survey channel, 6 way switch amount input channels, 6 tunnel analog input channels, 3 way switch amount output channels.

The specific implementation of 2 pairs of the utility model is for a more detailed description below in conjunction with the accompanying drawings.

The utility model discloses a kind of tachometric survey for DCS system and control systems, are Xinhua's NetPAC systems One of system module, the present invention uses the LCMXO2-2000 chips of Lattice companies, uses Verilog programming languages. Hardware logic module has been built inside FPGA, inside realize rotating speed or impulse measuring, its abundant pipe can be utilized Foot resource realizes the measurement of multichannel rotating speed amount simultaneously.

The present invention, hardware circuit core processing unit use the high-performance ARM chips of 32, and model MB9BF618S uses C Calculating to rotating speed, the control of hypervelocity, unbalanced power logic are realized in Programming with Pascal Language.When the speed of measurement object is more than setting During value, with reference to On-off signal signal and analog input signal, protection letter is sent out after being calculated by microcontroller according to control strategy Number, fast response time is feature-rich, and single module can complete multiple functions, easy to use.

Filtering and isolation circuit has also been devised in the utility model, improves the antijamming capability of device.

3 tunnel speed control channels are using interference of the optocoupler EL357N isolation field devices to measuring system, to protect internal control Circuit works normally.6 way switch amounts input and 3 way switch amounts output all using optocoupler EL357N realize internal and external parts circuit every From.At input signal end using filter circuit, filtering clutter signal.

Analog input channel in turn samples 6 road signals by the way of switching, and sampling A/D chip uses ADS8320E, the converter conversion speed is fast, supports spi bus.Isolating chip uses high-speed isolated chip ADuM1201, is high Fast magnetic medium isolating chip can be isolated interference of the field device to it, ensure its normal work.

The preferred embodiment of the utility model described in detail above.It should be appreciated that the ordinary skill people of this field Member according to the present utility model can conceive without creative work makes many modifications and variations.Therefore, all this technology necks Technical staff passes through logic analysis, reasoning or limited reality on the basis of existing technology according to the design of the utility model in domain Available technical solution is tested, it all should be in the protection domain being defined in the patent claims.

Claims

A kind of 1. rotation speed measuring module for DCS system, including detection circuit and sample-taking calculating circuit, which is characterized in that institute It states sample-taking calculating circuit and further includes programmable logic chip FPGA and microcontroller, the detection circuit is used to locate signal in advance Reason provides signal for the programmable logic chip FPGA, and the microcontroller and programmable logic chip FPGA communications connect It connects, wherein the programmable logic chip FPGA is used for counting and timing to tacho-pulse, obtains count value C and clocking value T, The microcontroller calculates rotating speed for reading the C values cached in the programmable logic chip FPGA and T values.
2. it to be used for the rotation speed measuring module of DCS system as described in claim 1, which is characterized in that further include and compiled with described The input channel and/or output channel of journey logic chip FPGA connections.
3. it to be used for the rotation speed measuring module of DCS system as claimed in claim 2, which is characterized in that the input channel includes Tachometric survey channel, On-off signal channel and analog input channel.
4. it to be used for the rotation speed measuring module of DCS system as claimed in claim 3, which is characterized in that the tachometric survey channel For 3 tunnels, the On-off signal channel is 6 tunnels, and the analog input channel is 6 tunnels.
5. it to be used for the rotation speed measuring module of DCS system as claimed in claim 2, which is characterized in that the output channel includes Output switch parameter channel.
6. it to be used for the rotation speed measuring module of DCS system as claimed in claim 5, which is characterized in that the output switch parameter leads to Road is 3 tunnels.
7. it to be used for the rotation speed measuring module of DCS system as claimed in claim 3, which is characterized in that the tachometric survey channel, On-off signal channel and analog input channel realize that internal and external parts circuit is isolated using optocoupler EL357N.
8. it to be used for the rotation speed measuring module of DCS system as claimed in claim 4, which is characterized in that the analog input leads to Road in turn samples 6 road signals by the way of switching, sampling A/D chip ADS8320E.
9. be used for the rotation speed measuring module of DCS system as claimed in claim 8, which is characterized in that in the sampling A/D chip and Isolating chip is further included between the programmable logic chip FPGA, the isolating chip is the isolation of ADuM1201 high speeds magnetic medium Chip.
10. it to be used for the rotation speed measuring module of DCS system as described in claim 1, which is characterized in that the microcontroller is 32 High-performance ARM chips, model MB9BF618S.