CN205808587U - Pipeline fluid temperature measuring equipment based on FPGA - Google Patents

Abstract

This utility model relates to a kind of pipeline fluid temperature measuring equipment based on FPGA.Two relative ultrasonic transducers are placed in the pipe ends needing thermometric, fpga chip is as main control chip, control one group of sine wave digital signal of output, control one of them ultrasonic transducer by peripheral circuits such as DA change-over circuit, amplifying circuit and channel selection circuits and launch one group of sine wave signal, the digital waveform that the ultrasonic echo signal received by another transducer is obtained by A/D convertor circuit extracts clawback signal characteristic value after digital filtering, by serial communication, eigenvalue is uploaded to host computer；Host computer analytical calculation obtains the ultrasound wave propagation time at pipeline fluid, can be calculated ultrasonic velocity by measuring the distance between two ultrasound probes, the functional relation of ultrasonic velocity and fluid temperature (F.T.) can be calculated again the temperature of fluid；This device can display pipes fluid temperature (F.T.) directly perceived, and measurement result is generated form.

Description

Pipeline fluid temperature measuring equipment based on FPGA

Technical field

This utility model designs a kind of pipeline fluid temperature measuring equipment based on FPGA.

Background technology

Pipeline transportation plays key player in commercial production and the energy are transported, it is impossible to accurately measure the stream of transport pipeline Temperature can cause consuming substantial amounts of additional energy source, in order to reduce energy resource consumption, the safe transport ensureing oil gas and relevant device Even running, it is necessary to the temperature of oil gas is strictly monitored.

In the industry spot of pipeline transportation, conventional sensor for measuring temperature has following three kinds: thermocouple TC, thermal resistance Three class such as RTD, critesistor, it is sex-limited the most to some extent to there is survey bureau in these three temp measuring method.Wherein thermocouple measurement model Enclosing wider, response is fast, but perishable, and error is bigger；Thermal resistance is linearly preferable, but sensitivity is low；The measurement of critesistor Precision is high, highly sensitive, but affected by environment relatively big, and temperature-measuring range is little, the most poor.

The method of ultrasound wave pipeline thermometric is compared with above-mentioned three kinds of methods, because having fast, lossless, the sensitivity of response High, not by pipeline radiation effect, measure the features such as wide ranges, be increasingly subject to domestic and international research worker and pay attention to.The thermometric of ultrasound wave Being to utilize ultrasound wave velocity of wave in same medium to change along with medium temperature change, ultrasonic velocity formula is as followsWherein, c sound wave velocity of wave in media as well, m/s；γ gas adiabatic coefficent specific heat at constant pressure and specific heat at constant volume Hold ratio；R mol gas constant, 8.314；T gas temperature, K；M molecular weight gas, kg/mol.Utilize this characteristic, The velocity of wave that only need to measure ultrasound wave can accurately measure the transient temperature of fluid in industry spot pipeline.

Utility model content

The weak point existed for above-mentioned prior art, this utility model provides one to respond fast, lossless, sensitivity High, not by pipeline radiation effect, the pipeline fluid temperature measuring equipment based on FPGA of measurement wide ranges.

The purpose of this utility model is achieved through the following technical solutions: a kind of pipeline fluid thermometric based on FPGA fills Put, including host computer, FPGA control module, ultrasonic pulse sending module, ultrasonic transducer, channel selecting module, signal Acquisition module, described host computer connects FPGA control module, FPGA control module connects ultrasonic pulse respectively and sends mould Block 3, signal acquisition module, ultrasonic pulse sending module, signal acquisition module interface channel select module, channel selecting module Connect ultrasonic transducer.

Compared with prior art, this utility model has the advantages that

1, this utility model is with FPGA as main control chip, and the characteristic that its high speed is stable is capable of the time to each sensitivity Node accurately monitors, and coordinates high-speed a/d and D/A conversion chip, and sampling rate can reach 100,000,000 grades, it is achieved more accurate With quick pipeline fluid thermometric；2, this utility model uses digital form to produce sine wave, and the digital form of employing is direct Digital frequency synthesis technology DDS Direct Digital Synthesize, generates sine wave compared to traditional analog form, The advantage that DDS is low in energy consumption, low cost, speed are fast, resolution is high；3, this utility model employing is the IP kernel of ISE Integrated Simulation FIR Compiler v5.0, compared to analog filter, Finite Impulse Response filter is it can be avoided that temperature drift, voltage drift, noise etc. Problem, thus improve the precision of measurement；4, this utility model host computer analyzing and processing data, can carry out organizing measurement more and missing Difference is revised, and can carry out uncertainty simultaneously and repeatability is analyzed, improve temperature measurement accuracy and reliable measuring data.

Accompanying drawing explanation

Fig. 1 is the structural representation of this utility model monitoring device.

Fig. 2 is 3.3V power module.

Fig. 3 is 2.5V power module.

Fig. 4 is 1.2V power module.

Fig. 5 is serial communication circuit schematic diagram.

Fig. 6 is DDS output ultrasonic wave digital signal schematic diagram.

Fig. 7 is ultrasonic pulse transtation mission circuit.

Fig. 8 is channel selection circuit.

Fig. 9 is high speed analog signal Acquisition Circuit.

Figure 10 is Finite Impulse Response filter structural representation.

Figure 11 is that ultrasonic echo signal zero crossing extracts schematic diagram.

Detailed description of the invention

Below in conjunction with the accompanying drawings this utility model is described in more details.

As it is shown in figure 1, a kind of pipeline fluid temperature measuring equipment based on FPGA, a kind of pipeline fluid thermometric based on FPGA fills Put, control mould 2, ultrasonic pulse sending module 3, ultrasonic transducer 4, channel selecting module 5, letter including host computer 1, FPGA Number acquisition module 6, described host computer 1 connects FPGA control module 2, and FPGA control module 2 connects ultrasonic pulse respectively Sending module 3, signal acquisition module 6, ultrasonic pulse sending module 3, signal acquisition module 6 interface channel select module 5, logical Road selects module 5 to connect ultrasonic transducer 4.

Described FPGA control module uses the XC3S500E chip of the Spartan-3E series of Xilinx company exploitation, main The transmission of ultrasonic pulse to be controlled, the collection of analogue signal and control host computer and the communication of slave computer；Ultrasonic wave transducer Device is for launching and return pulse signal；Ultrasonic pulse transtation mission circuit includes the ISL5961 D/A that Intersil company produces Conversion chip, voltage feed-back amplifier THS4271 chip, FPGA is controlled one group of sine wave numeral of output by ISL5961 chip Signal is converted into analogue signal, then amplifies, by THS4271 chip, the analogue signal that ISL5961 chip exports, and is that ultrasound wave is visited Hair penetrates one group of sinusoidal wave pulse；Channel selection circuit includes CD4052B chip, controls the direction of propagation of ultrasound wave；At a high speed Analogue signal acquisition circuit includes AD6645 chip, and ultrasonic echo signal is carried out analog digital conversion；Host computer LabVIEW Design, for slave computer sends control instruction, and the data sending slave computer are analyzed calculating.

First powering to temperature measuring equipment, power module is as shown in Figure 2, Figure 3, Figure 4；2-1 serial ports in FPGA control module Communicating circuit figure is as it is shown in figure 5, make host computer and slave computer communication；Fig. 6 is the IP kernel 2-2DDS of ISE Integrated Simulation Compiler and 2-3Block Memory Generator uses direct digital frequency synthesis technology sine wave output digital signal Schematic diagram；For making ultrasonic transducer launch sine wave signal, the sinusoidal undulation number signal that DDS generates need to be converted into simulation letter Number, 3 ultrasonic pulse sending modules high frequency D/A converting circuit as shown in Figure 7, wherein ISL5961 chip is that high frequency modulus turns Change chip；Channel selecting module controls transmitting and the reception of ultrasonic transducer pulse signal, defeated with the analogue signal shown in Fig. 7 Go out end to be connected, as shown in Figure 8；For gathering the echo-signal of ultrasonic pulse signal, echo-signal need to be converted into digital signal Processing, high speed analog signal acquisition module is as it is shown in figure 9, be connected with ultrasound probe one end of return pulse signal；2- 3Fir Compiler is that the digital waveform generated ultrasonic echo signal through analog to digital conversion circuit carries out digital filtering, it is to avoid The interference signal impact on measurement result, Fir Compiler structure as shown in Figure 10, mainly uses adder, multiplier and deposits Storage resource；2-5 is data storage and Algorithm Analysis module, and data storage is that the digital waveform to echo-signal stores, and calculates Method analysis and clawback signal carries out zero crossing extraction, as shown in figure 11, when last of the ultrasonic pulse signal launched Sinusoidal wave arrival transducer a, it may appear that crest, zero point T1 extracting this characteristic wave is ultrasonic propagation time.

The using method of said apparatus mainly comprises the steps that

1 first need thermometric pipe ends place two just to ultrasonic transducer, measures two pop one's head between Distance L, to temperature measuring equipment be energized；

2 host computers send instruction by serial communication to slave computer, control slave computer and perform order；

3 FPGA control modules control DDS sine wave output digital signal, open when exporting last sine wave signal Beginning timing；

The digital signal that DDS exports is converted into analogue signal by 4 ultrasonic pulse transtation mission circuits, through channel selection circuit control Make one of them ultrasonic transducer and launch sinusoidal wave pulse signal；

Ultrasonic echo signal is converted into digital signal by 5 high speed analog signal Acquisition Circuit, and by FIR digital filtering Device eliminates the impact of interference signal；

6 pairs of echo-signals through digital filtering carry out Algorithm Analysis, and zero crossing extracts and obtains ultrasonic propagation time T1；

Propagation time T1 is uploaded to host computer through serial communication by 7, is analyzed process, error correction by host computer, Display pipes fluid temperature (F.T.) in real time, and measurement result is generated form.

Claims (1)

1. a pipeline fluid temperature measuring equipment based on FPGA, including host computer (1), FPGA control module (2), ultrasonic pulse Sending module (3), ultrasonic transducer (4), channel selecting module (5), signal acquisition module (6), it is characterised in that: described Host computer (1) connect FPGA control module (2), FPGA control module (2) connects respectively ultrasonic pulse sending module (3), Signal acquisition module (6), ultrasonic pulse sending module (3), signal acquisition module (6) interface channel select module (5), passage Module (5) is selected to connect ultrasonic transducer (4).