CN205483107U - High accuracy electric -magnetic flow meter based on fast fourier transform - Google Patents
High accuracy electric -magnetic flow meter based on fast fourier transform Download PDFInfo
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- CN205483107U CN205483107U CN201620196413.6U CN201620196413U CN205483107U CN 205483107 U CN205483107 U CN 205483107U CN 201620196413 U CN201620196413 U CN 201620196413U CN 205483107 U CN205483107 U CN 205483107U
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Abstract
The utility model discloses a high accuracy electric -magnetic flow meter based on fast fourier transform, this flowmeter includes switching power supply circuit, master control circuit, excitation circuit, a pre -amplifying circuit, frequency output circuit, alarm output circuit, 4~20mA output circuit, HART communication circuit and RS485 communication circuit, master control circuit is last according to electric return circuit mode hookup switching power supply circuit, excitation circuit, a pre -amplifying circuit, frequency output circuit, alarm output circuit, 4~20mA output circuit, HART communication circuit and RS485 communication circuit, wholly constitute electric -magnetic flow meter's electric return circuit. The utility model discloses a fast fourier transform (FFT) analytical approach branch is appeared thoughtlessly has interfering signal's traffic signal frequency spectrum, unanimous according to the frequency of traffic signal and excitation signal, goes up on traffic signal frequency known basis and isolates interfering signal and traffic signal, through the amplitude that FFT calculates traffic signal, expands the electric -magnetic flow meter range and compares, realizes small flow high precision measurement.
Description
Technical field
This utility model relates to field of flow detection, is specifically related to a kind of high-accuracy electromagnetic flowmeter based on fast Fourier transform.
Background technology
Electromagnetic flowmeter is the instrument measuring conducting liquid volume flow according to Faraday law of electromagnetic induction.The widely used excitation mode of electromagnetic flowmeter has low-frequency square-wave excitation and three value weve.Both excitation modes overcome orthogonal interference, differential interference, homophase interference, series mode interference etc. interference signal to a certain extent, improve certainty of measurement, but when low flow velocity, owing to sensor signal is faint, the signal to noise ratio making sensor output signal declines, traditional metering system cannot be distinguished by out interference signal and flow signal so that electromagnetic flowmeter range ratio and tiny flow quantity high-acruracy survey are restricted.
Summary of the invention
The purpose of this utility model is: provide a kind of high-accuracy electromagnetic flowmeter based on fast Fourier transform, fast Fourier transform (FFT) analytical is used to go out the flow signal frequency spectrum being mixed with interference signal, consistent with the frequency of excitation signal according to flow signal, on the basis of known to flow signal frequency, interference signal and flow signal are separated, amplitude by FFT computing flow signal, extension electromagnetic flowmeter range ratio, it is achieved tiny flow quantity high-acruracy survey.
Technical solution of the present utility model is: should include switching power circuit by high-accuracy electromagnetic flowmeter based on fast Fourier transform, governor circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit, switching power circuit is coupled according to electricity circuit type on governor circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit, it is monolithically fabricated the electric loop of electromagnetic flowmeter.
The utility model has the advantages that:
1, civil power 220V is transformed into+14V ,-14V ,+5V ,+25V by switching power circuit, become+12V ,-12V ,+3.3V ,+24V by voltage stabilizing chip voltage stabilizing again, provide power supply to field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit, RS485 telecommunication circuit.
2, field circuit provides low-frequency square-wave excitation for cell winding.
3, flow signal is transformed into digital quantity then FFT computing by AD after amplifying filtering and calculates flow rate again by the realization simulation teletransmission of 4 ~ 20mA output circuit by pre-amplification circuit, it is also possible to realize digital telemetering by frequency output circuitry and HART communication circuit, RS485 telecommunication circuit.
4, fast Fourier transform FFT algorithm Digital Signal Processing is used, realize Electromagnetic Flow signal to change from time domain to frequency domain, analog signal processing is converted into Digital Signal Processing, accurately flow signal can be separated when small amount of flow measuring by spectrum analysis, widen range ratio, realize the high-acruracy survey of tiny flow quantity, there is the advantages such as certainty of measurement height, reliability height, good, the flexible design of concordance.
Accompanying drawing explanation
Fig. 1 is this utility model hardware block diagram.
Fig. 2 is this utility model power supply rectification filter circuit.
Fig. 3 is this utility model switching power circuit.
Fig. 4 is this utility model field circuit.
Fig. 5 is this utility model pre-amplification circuit.
Fig. 6 is this utility model 4 ~ 20mA output circuit.
Fig. 7 is this utility model RS485 telecommunication circuit.
Fig. 8 is this utility model HART communication circuit.
Fig. 9 is this utility model governor circuit.
Figure 10 is this utility model frequency output circuitry.
Figure 11 is this utility model alarm output circuit.
Figure 12 is this utility model excitation con-trol and AD controlling of sampling sequential chart.
Detailed description of the invention
Describe detailed description of the invention of the present utility model below in conjunction with the accompanying drawings in detail.
Core of the present utility model is: fast Fourier transform technology is applied to electromagnetic flowmeter signal and processes, the size being understood induction electromotive force by the principle of electromagnetic flowmeter is directly proportional to rate of flow of fluid, conventional scheme is directly to measure induction electric size then to calculate flow, this utility model, according to the signal frequency characteristic consistent with excitation frequency, realizes digital filtering by fast fourier transform algorithm and is directly calculated by the crest meter of the flow signal of corresponding excitation frequency.
General hardware block diagram of the present utility model is as shown in Figure 1, including switching power circuit, governor circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit, couple switching power circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit according to electricity circuit type on governor circuit, be monolithically fabricated the electric loop of electromagnetic flowmeter.
Power circuit design performance of the present utility model is related to the performance of whole effusion meter.Flowmeter electronics needs the voltage that many groups are different, and some voltage the most directly also needs to isolation, and the ripple factor of power supply directly affects the sensitivity of amplifying circuit, so other instrument power circuit that compares want complicated many.The front-end circuit of switching power circuit is as in figure 2 it is shown, the annexation of current rectifying and wave filtering circuit is: a termination critesistor RT1 of 220V connector J1, centre is directly grounded, and another terminates electric fuse FU1；Another termination varistor RV1, RV3 and electric capacity C5, one end of filter inductance input pin of RT1；Another termination gas-discharge tube and one end of varistor RV2 of varistor RV3；Another termination varistor RV1, RV2 and electric capacity C5 of electric fuse FU1, the other end of filter inductance input；The other end ground connection of gas-discharge tube；One termination capacitor C3 of filter inductance output, C4 input one end with exchanging of rectifier bridge D1；Filter inductance exports another termination C6 one end of another termination capacitor C4 and exchanges the input other end with rectifier bridge D1；Electric capacity C3 and C6 other end ground connection；Rectifier bridge D1 exports a termination capacitor C9 anode, another termination capacitor C9 negative terminal of rectifier bridge D1；Electric capacity CY1 mono-termination capacitor C9 anode;One termination capacitor C9 negative terminal.
Fig. 3 is switching power circuit, produce need+12V ,-12V ,+24 ,+25V, 5V, its circuit connecting relation is: electric capacity C22 is just terminating the negative input end of Z1 TL431 and one end of resistance R7, one end of resistance R8, optocoupler U33 input negative terminal；Electric capacity C22 negative terminal connects one end of the anode resistance R10 of Z1；The other end of the reference edge connecting resistance R10 of Z1 and one end of electric capacity C8, one end of resistance R9；One end of another termination capacitor C7 of resistance R9；The other end of the other end connecting resistance R8 of electric capacity C8；One end of the other end connecting resistance R6 of resistance R7；Another termination optocoupler U33 of resistance R6 inputs anode；The output one termination capacitor C12 anode of optocoupler U33 and one end of resistance R2；The negative terminal of electric capacity C12 connects high frequency transformer T13 foot；High frequency transformer T13 foot is connected with negative the connecing of electric capacity C9；Another terminating diode VD1 negative terminal of resistance R2；Diode VD1 is just terminating high frequency transformer T14 foot；Another termination capacitor C25 one end of optocoupler U33 and one end of R11 and 1 foot of switching power source chip U1；C25 another termination C26 bears termination capacitor C9 negative terminal；The electric capacity C26 positive terminating resistor R11 other end；The 3 of switching power source chip U1,4,5 feet connect electric capacity C9 negative terminal；2 feet of switching power source chip U1 connect one end of R5；The anode of another termination C9 of R5；7 feet of switching power source chip U1 connect anode and the high frequency transformer T12 foot of diode D3；The negative terminal of D3 connects one end of R1；The other end of R1 and the negative pole of transient state pipe D2, one end of R3, one end of C10 connect；1 foot of the other end of D2 and the other end of R3 and the other end of C10 and high frequency transformer T1 connects；5 feet of T1 connect the positive level of diode VD2；One end of the negative pole of diode and the positive level of electric capacity C13, inductance L2 connects；6 feet of T1 connect the negative pole with C13, the negative pole of C17, C23 one end with together with；The positive level of another termination C17 of L2 connects the other end of C23；7 feet of T1 connect the positive level of VD6；One end of the negative pole of VD6 and the positive level of electric capacity C11 and inductance L6 connects；The positive level of another termination capacitor C21 of inductance and one end of C7；8 feet of T1 and the negative terminal of C11, C21 negative terminal, the other end of C7 connect；9 feet of T1 connect the positive level of diode VD3；VD3 bears termination capacitor C14 anode, inductance L3 one end；Another termination capacitor C18 anode of inductance L3 and electric capacity C24 one end；The electric capacity C24 other end and C18 negative terminal, C14 negative terminal, 10 feet of T1 connect；11 feet of T1 connect the anode of diode VD4；The negative terminal of VD4 and electric capacity C15 anode, inductance L4 one end connect；One end of the inductance L4 other end and electric capacity C19 anode and electric capacity C1 connects；The other end of electric capacity C1 and the negative terminal of C19, the negative terminal of C15,12 feet of T1 connect；12 feet of T1 and electric capacity C16 anode, electric capacity C20 anode, one end of electric capacity C2 connect；13 feet of T1 and the negative terminal of diode VD5 connect；One end of VD5 anode and electric capacity C16 negative terminal inductance L5 connects；The inductance L5 other end and the negative terminal of electric capacity C20, the other end of electric capacity C2 connects.
The stability in magnetic field is had an impact by field circuit of the present utility model, thus flow signal accuracy is produced impact；This utility model uses switch mode constant current excitation mode, improves the stability in magnetic field, lays the foundation for high-acruracy survey；As shown in Figure 4, the annexation of field circuit is: the D pole of metal-oxide-semiconductor Q13 is extremely connected with the G of metal-oxide-semiconductor Q10 with one end of resistance R17；Metal-oxide-semiconductor Q13G level and OP1 connect；The S pole of Q3 and the S pole of resistance R29 one end and one end of resistance R30 and metal-oxide-semiconductor Q12 connect；The other end of R29 and metal-oxide-semiconductor Q11G pole and metal-oxide-semiconductor Q10 S pole connect；The D pole of metal-oxide-semiconductor Q11 and the S pole of metal-oxide-semiconductor Q7 connect；The S pole of Q11 and the S pole of metal-oxide-semiconductor Q14 connect；The D pole of metal-oxide-semiconductor Q14 and the S pole of metal-oxide-semiconductor Q6 connect；The G pole of metal-oxide-semiconductor Q14 and one end of resistance R30 connect；The other end of resistance R30 and one end of resistance R29 connect；The G pole of Q14 and the S pole of Q9 connect；The G pole of Q9 and resistance R26 one end；Resistance R26 another termination+12V；The D pole of Q12 connects the G pole of Q9；One end of the D pole connecting resistance R24 of Q6 and the D pole of one end of resistance R23 and metal-oxide-semiconductor Q7；The G pole of Q6 connects the other end of R24；The G pole of Q7 connects the other end of R23；The 1 of switching power source chip U8,6,7,8 feet link+12V；4 feet of U8 connect the ground of 3.3V power supply；5 foot connecting resistance R37 and one end of resistance R34 of U8；Resistance R37 mono-terminates the ground of 3.3V power supply；3 feet of U8 connect one end of C22；The one termination 3.3V power supply ground of C22；2 feet of U8 connect the negative pole of diode D15；The negative pole of diode D15 connects the ground of 3.3V power supply；2 feet of the one termination U8 of inductance L4；The other end of the other end connecting resistance R34 of inductance L4；The other end of the one termination inductance L4 of electric capacity C21；Another termination 3.3V power supply ground of electric capacity C21；12 feet of amplifier U3 are connected with one end of resistance R7 and resistance R3；The other end of resistance R7 is connected with the negative pole of voltage reference U1；The positive level ground connection of voltage reference U1；The other end of resistance R7 is connected with one end of resistance R6；One end of resistance R9 is connected with one end of resistance R12；The other end of resistance R9 is connected with 13 feet of amplifier U3；10 feet of amplifier are connected with one end of resistance R18；The other end of resistance R18 is connected with one end of resistance R19；The other end of resistance R19 is connected with one end of resistance R21；The other end of resistance R21 is connected with resistance R20；The other end of resistance R20 is connected with 8 feet of amplifier U3；One end of one first lunar month resistance R13 of electric capacity C11 connects；The other end of resistance R13 is connected with one end of the other end of C11 and R8；One end of the other end of resistance R8 and electric capacity C6, C7, C8, C9, C4 connects and diode D7, D8 positive pole and diode D9, D20 negative pole connect；The other end of D7 is connected with the S pole of metal-oxide-semiconductor Q1；The D pole of Q2 connects in succession with the negative of diode D4；The negative pole of diode D8 is connected with the positive pole of diode D4；The positive pole of diode D20 is connected with one end of resistance R51；The other end of resistance R51 is connected with the emitter stage of audion Q20；The base stage of Q20 is connected with the positive pole of diode D20；The colelctor electrode of Q20 is connected with one end of resistance R50；The D pole of metal-oxide-semiconductor Q5 is connected with the positive pole of diode D9 and one end of inductance L1 connects；The S pole of metal-oxide-semiconductor Q5 is connected to ground；The G pole of metal-oxide-semiconductor Q5 is connected with 4,6,8,10,12 feet of Schmidt U2；2 feet of the 3 of U2,5,9,11,13 feet and U2 connect；1 foot of U2 and one end of resistance R50 connect；The negative pole of diode D2 is connected with the positive pole of diode D5；The positive pole of diode D2 is connected with the positive pole of diode D3；The negative pole of diode D3 is connected with the positive pole of diode D6；The negative pole of diode D6 is connected with the negative pole of diode D5；8 feet of switching power source chip U4 are connected with one end of resistance R10；The other end of resistance R10 is connected with 6 feet of U4 and one end of inductance L2；7 feet of U4 are connected with one end of resistance R10；5 feet of U4 are connected with one end of resistance R17, resistance R11；3 feet of U4 are connected with one end of electric capacity C14；The other end of electric capacity C14 is connected with 4 feet of U4；2 feet of U4 are connected with 4 feet of U4；The positive pole of another first lunar month D10 of inductance L2 connects；The negative pole of D10 is connected with the other end of resistance R11；The other end of resistance R11 is connected with one end of electric capacity C12;The other end of electric capacity C12 is connected with 4 feet of U4.
Signal amplification circuit of the present utility model is that the sensor sensing electromotive force small-signal of electromagnetic flowmeter carries out suppression common mode disturbances while differential amplification, and it is not very big that first order gain is arranged, and prevents rear class amplifying circuit saturated；The second level carries out low-pass filtering, and interference signal is simulated filtering；Entering AD again to sample, nyquist sampling law is followed in FFT sampling；As it is shown in figure 5, the annexation of pre-amplification circuit is: one end of 5 foot connecting resistance R4 of amplifier U2；One end of 6 foot connecting resistance R5 of amplifier and one end of R7 and one end of C2；The other end of another termination capacitor C2 of resistance R4 and one end of resistance R8；The other end of the other end connecting resistance R7 of resistance R8；7 feet of another termination amplifier U2 of resistance R5；5 feet of amplifier connect one end of electric capacity C3；Another termination instrument of electric capacity C3 amplifies output 6 foot of U3；The one end of the 1 foot connecting resistance R3 that instrument is amplified；Instrument amplifies the other end of the 8 foot connecting resistance R3 of U3；Instrument amplifies one end of the 2 foot connecting resistance R6 of U3；One end of another termination capacitor C4 of resistance R6；One end of another termination capacitor C1 of electric capacity C4；The other end ground connection of electric capacity C1；Instrument amplifies one end of the 3 foot connecting resistance R9 of U3；One end of another termination capacitor C6 of resistance R9；One end of 5 foot connecting resistance R2 of AD conversion U1；5 feet of the one termination U1 of resistance R1.
This utility model 4 ~ 20mA output circuit uses PWM type DA to be changed by U/I, and its temperature drift precision is high；As shown in Figure 6, the annexation of 4 ~ 20mA output circuit is: a terminating resistor R36 of electric capacity C20 and resistance R31 and 13 feet of schmidt trigger U5F；One end of another termination capacitor C17 of resistance R31 and one end of electric capacity C18；One end of the other end connecting resistance R33 of electric capacity C17 and one end of resistance R35；The other end of the other end connecting resistance R33 of electric capacity C18 and the positive input terminal of amplifier U10A；12 feet of another termination Schmidt trigger U5F of resistance R35；The negative electrode of benchmark U9 connects with one end of electric capacity C18；The other end of the anode connecting resistance R36 of benchmark U9；The negative electrode of the one termination benchmark U9 of electric capacity C19；The negative electrode of stabilivolt D14 connects the negative electrode of benchmark U9；One end of the anode connecting resistance R38 of stabilivolt D14；The anode of another termination benchmark U9 of resistance R38；The anode of the one termination stabilivolt D14 of resistance R39 and 4 feet of amplifier U10A；The other end ground connection of resistance R39；8 feet of amplifier U10A meet 24V；The drain electrode of the negative input termination metal-oxide-semiconductor Q15 of amplifier；The grid of the output termination metal-oxide-semiconductor Q15 of amplifier U10A；The source electrode of metal-oxide-semiconductor Q15 connects the anode of diode D16；One end of the negative input end connecting resistance R32 of amplifier；The negative electrode of another termination stabilivolt D14 of resistance R32；The negative electrode of stabilivolt D14 connects the negative electrode of Light-Emitting Diode D13；The anode of light emitting diode D13 meets 24V.
This utility model RS485 telecommunication circuit is as it is shown in fig. 7, its annexation is: one end of the 1 foot connecting resistance R40 of 485 chip U11；2 feet of 485 chip U11 and 3 feet are connected；The 5 foot ground connection of 485 chip U11；One end of the foot 6 foot connecting resistance R42 of 485 chip U11 and the negative electrode of transient state pipe D17；The other end ground connection of resistance R42；The plus earth of transient state pipe D17；One end of the 7 foot connecting resistance R41 of 485 chip U11 and the negative electrode of transient state pipe D18；Another termination 5V of resistance R41；The plus earth of transient state pipe D18.
As shown in Figure 8, its annexation is this utility model HART communication circuit: 1 foot of HART chip and 2 feet are connected 3.3V；3 foot ground connection of HART chip；The one termination 3.3v of electric capacity C2；The other end ground connection of electric capacity C2；7 feet of HART chip connect one end and one end of electric capacity C3 of crystal oscillator；8 feet of HART chip connect the other end and one end of electric capacity C4 of crystal oscillator；The other end ground connection of electric capacity C3；The other end ground connection of electric capacity C4；9 feet of HART chip, 10 foot ground connection；11 feet of HART chip meet 3.3V；11 feet of HART chip connect one end of electric capacity C5；The other end ground connection of electric capacity C5；One end of 12 foot connecting resistance R4 of HART chip；Another termination capacitor C10 of resistance R4 and the positive input terminal of amplifier U2 and；The other end ground connection of electric capacity C10；13 feet of HART chip connect electric capacity C6, C7, one end of resistance R2；The other end ground connection of electric capacity C6, C7；Another termination 14 feet of HART chip, resistance R1, one end of electric capacity C8 of resistance R2；The other end ground connection of resistance R1；Another termination capacitor C9 of electric capacity C8, one end of resistance R3；The other end ground connection of electric capacity C9；One end of another termination capacitor C11 of resistance R3；15 feet of HART chip, 16 feet, 17 feet, 18 foot ground connection；Electric capacity C1, C14 mono-terminates 3.3V；Electric capacity C1, C14 other end ground connection；2 foot ground connection of amplifier U2；5 feet of amplifier U2 connect 3.3V and one end of electric capacity C12；The other end ground connection of electric capacity C12；The output of negative input termination amplifier U2 of amplifier U2；The output of amplifier connects one end of electric capacity C13.
Governor circuit of the present utility model is as it is shown in figure 9, its annexation is: the 22 of single-chip microcomputer U4,53,63 feet are connected with one end of electric capacity C8 and one end of electric capacity C9;The other end of electric capacity C8 is connected with one end of crystal oscillator Y1；The other end of crystal oscillator Y1 is connected with the other end of electric capacity C9；Level is practiced in one end of 20 feet of single-chip microcomputer and electric capacity C11；The other end ground connection of electric capacity C11；Another termination VCC of resistance R14；The outfan of voltage stabilizing chip V1 is connected with one end of electric capacity；The other end of electric capacity is connected with the common port of voltage stabilizing chip V1；The input termination 5V of voltage stabilizing chip V1, V2, V3；The other end of the output capacitor C10 of voltage stabilizing chip V2；The one termination common port of electric capacity C10；The outfan of the one termination voltage stabilizing chip V3 of electric capacity C14；The common port of another termination voltage stabilizing chip V3 of electric capacity C14；One end of the 6 foot connecting resistance R12 of operational amplifier U5；Another termination+5V of resistance R12；One end of 6 foot connecting resistance R10 of amplifier U5；Outfan 7 foot of another termination amplifier of resistance R10；3 feet of amplifier U5 and 5 foot ground connection；The other end of 2 foot connecting resistance R15 of amplifier；Another termination+3V of resistance R15；One end of 2 foot connecting resistance R13 of amplifier；1 foot of another termination amplifier of resistance R13；8 feet of single-chip microcomputer U30 connect one end of electric capacity C31；The other end ground connection of electric capacity C31；9 feet of Schmidt trigger U8 connect one end of electric capacity C17；The other end ground connection of electric capacity C17；One end of the 9 foot connecting resistance R20 of U8；Another termination the 1 of U8,3,5,11,13 foot of resistance R20 also connects 8 feet of U8 simultaneously；The 2 of U8,4,6,10,12 feet connect one end of electric capacity C20；The negative pole of diode D2 connects the negative pole of diode D3 and connects one end of electric capacity C22, C23 simultaneously；The positive pole of diode D2 connects the negative pole of diode D4；The positive pole of diode D4 connects the positive pole of diode D5；The negative positive pole meeting D3 of diode D5；One end of electric capacity another termination capacitor C24 of C22；The other end of another termination capacitor C25 of electric capacity C24；The other end of one termination capacitor C23 of electric capacity C25；One end of electric capacity C13 one end resistance R16；The other end of the other end connecting resistance R16 of electric capacity C13；The input positive pole of another termination optocoupler U6 of resistance R16；The input minus earth of optocoupler U6；The colelctor electrode of optocoupler U6 meets 3.3V；The emitter stage of optocoupler U6 connects the colelctor electrode of optocoupler U7；The grounded emitter of optocoupler U7；The input positive pole of optocoupler U7 meets VCC；One end of the negative pole connecting resistance R17 of optocoupler U7；One end of another termination capacitor C15 of resistance R17；The input negative pole of another termination optocoupler of electric capacity C15；The input positive pole of optocoupler U9 and one end of one end of electric capacity C16 and resistance R18 connect；The resistance R18 other end connects with the other end of electric capacity C16 and is connected with optocoupler U7 negative pole；The other end of resistance R18 is connected with one end of resistance R19 and one end of electric capacity C18；The other end of electric capacity C18 and resistance R19 connects；The input minus earth of optocoupler U9；Optocoupler U9 output colelctor electrode connects 3.3V optocoupler U9 output emitter stage and connects optocoupler U10 colelctor electrode；U10 grounded emitter；The colelctor electrode of optocoupler U11 meets VCC；The emitter stage of U11 and the colelctor electrode of optocoupler U12 connect；The grounded emitter of U12；The input positive pole of U11 connects one end of R21 and connects；The input positive pole of U11 is connected with C19 one end；The input positive pole of U12 connects 3.3V, input negative pole connecting resistance R22 one end and electric capacity C21 one end；The resistance R22 other end is connected with the electric capacity C21 other end.
As shown in Figure 10, its annexation is frequency output circuitry of the present utility model: optocoupler U33 input positive pole is connected with one end of resistance R61；Resistance R61 another termination 3.3V.
As shown in figure 11, its annexation is alarm output circuit of the present utility model: the input positive pole of optocoupler U25 is connected with resistance R87 one end；Resistance R87 another termination 3.3V.
Claims (10)
1. high-accuracy electromagnetic flowmeter based on fast Fourier transform, it is characterized in that: this effusion meter includes switching power circuit, governor circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit, couple switching power circuit, field circuit, pre-amplification circuit, frequency output circuitry, alarm output circuit, 4 ~ 20mA output circuit, HART communication circuit and RS485 telecommunication circuit according to electricity circuit type on governor circuit, be monolithically fabricated the electric loop of electromagnetic flowmeter.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, it is characterized in that: the annexation of the front end current rectifying and wave filtering circuit of switching power circuit is: a termination critesistor RT1 of 220V connector J1, centre is directly grounded, and another terminates electric fuse FU1；Another termination varistor RV1, RV3 and electric capacity C5, one end of filter inductance input pin of RT1；Another termination gas-discharge tube and one end of varistor RV2 of varistor RV3；Another termination varistor RV1, RV2 and electric capacity C5 of electric fuse FU1, the other end of filter inductance input；The other end ground connection of gas-discharge tube；One termination capacitor C3 of filter inductance output, C4 input one end with exchanging of rectifier bridge D1；Filter inductance exports another termination C6 one end of another termination capacitor C4 and exchanges the input other end with rectifier bridge D1；Electric capacity C3 and C6 other end ground connection；Rectifier bridge D1 exports a termination capacitor C9 anode, another termination capacitor C9 negative terminal of rectifier bridge D1；Electric capacity CY1 mono-termination capacitor C9 anode；One termination capacitor C9 negative terminal；Switching power circuit produce need+12V ,-12V ,+24 ,+25V, 5V, its circuit connecting relation is: electric capacity C22 is just terminating the negative input end of Z1 TL431 and one end of resistance R7, one end of resistance R8, optocoupler U33 input negative terminal；Electric capacity C22 negative terminal connects one end of the anode resistance R10 of Z1；The other end of the reference edge connecting resistance R10 of Z1 and one end of electric capacity C8, one end of resistance R9；One end of another termination capacitor C7 of resistance R9；The other end of the other end connecting resistance R8 of electric capacity C8；One end of the other end connecting resistance R6 of resistance R7；Another termination optocoupler U33 of resistance R6 inputs anode；The output one termination capacitor C12 anode of optocoupler U33 and one end of resistance R2；The negative terminal of electric capacity C12 connects high frequency transformer T13 foot；High frequency transformer T13 foot is connected with negative the connecing of electric capacity C9；Another terminating diode VD1 negative terminal of resistance R2；Diode VD1 is just terminating high frequency transformer T14 foot；Another termination capacitor C25 one end of optocoupler U33 and one end of R11 and 1 foot of switching power source chip U1；C25 another termination C26 bears termination capacitor C9 negative terminal；The electric capacity C26 positive terminating resistor R11 other end；The 3 of switching power source chip U1,4,5 feet connect electric capacity C9 negative terminal；2 feet of switching power source chip U1 connect one end of R5；The anode of another termination C9 of R5；7 feet of switching power source chip U1 connect anode and the high frequency transformer T12 foot of diode D3；The negative terminal of D3 connects one end of R1；The other end of R1 and the negative pole of transient state pipe D2, one end of R3, one end of C10 connect；1 foot of the other end of D2 and the other end of R3 and the other end of C10 and high frequency transformer T1 connects；5 feet of T1 connect the positive level of diode VD2；One end of the negative pole of diode and the positive level of electric capacity C13, inductance L2 connects；6 feet of T1 connect the negative pole with C13, the negative pole of C17, C23 one end with together with；The positive level of another termination C17 of L2 connects the other end of C23；7 feet of T1 connect the positive level of VD6；One end of the negative pole of VD6 and the positive level of electric capacity C11 and inductance L6 connects；The positive level of another termination capacitor C21 of inductance and one end of C7；8 feet of T1 and the negative terminal of C11, C21 negative terminal, the other end of C7 connect；9 feet of T1 connect the positive level of diode VD3；VD3 bears termination capacitor C14 anode, inductance L3 one end；Another termination capacitor C18 anode of inductance L3 and electric capacity C24 one end；The electric capacity C24 other end and C18 negative terminal, C14 negative terminal, 10 feet of T1 connect；11 feet of T1 connect the anode of diode VD4；The negative terminal of VD4 and electric capacity C15 anode, inductance L4 one end connect；One end of the inductance L4 other end and electric capacity C19 anode and electric capacity C1 connects；The other end of electric capacity C1 and the negative terminal of C19, the negative terminal of C15,12 feet of T1 connect；12 feet of T1 and electric capacity C16 anode, electric capacity C20 anode, one end of electric capacity C2 connect；13 feet of T1 and the negative terminal of diode VD5 connect；One end of VD5 anode and electric capacity C16 negative terminal inductance L5 connects；The inductance L5 other end and the negative terminal of electric capacity C20, the other end of electric capacity C2 connects.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, it is characterized in that: field circuit uses switch mode constant current excitation mode, and the annexation of field circuit is: the D pole of metal-oxide-semiconductor Q13 is extremely connected with the G of metal-oxide-semiconductor Q10 with one end of resistance R17；Metal-oxide-semiconductor Q13G level and OP1 connect；The S pole of Q3 and the S pole of resistance R29 one end and one end of resistance R30 and metal-oxide-semiconductor Q12 connect；The other end of R29 and metal-oxide-semiconductor Q11G pole and metal-oxide-semiconductor Q10 S pole connect；The D pole of metal-oxide-semiconductor Q11 and the S pole of metal-oxide-semiconductor Q7 connect；The S pole of Q11 and the S pole of metal-oxide-semiconductor Q14 connect；The D pole of metal-oxide-semiconductor Q14 and the S pole of metal-oxide-semiconductor Q6 connect；The G pole of metal-oxide-semiconductor Q14 and one end of resistance R30 connect；The other end of resistance R30 and one end of resistance R29 connect；The G pole of Q14 and the S pole of Q9 connect；The G pole of Q9 and resistance R26 one end；Resistance R26 another termination+12V；The D pole of Q12 connects the G pole of Q9；One end of the D pole connecting resistance R24 of Q6 and the D pole of one end of resistance R23 and metal-oxide-semiconductor Q7；The G pole of Q6 connects the other end of R24；The G pole of Q7 connects the other end of R23；The 1 of switching power source chip U8,6,7,8 feet link+12V；4 feet of U8 connect the ground of 3.3V power supply；5 foot connecting resistance R37 and one end of resistance R34 of U8；Resistance R37 mono-terminates the ground of 3.3V power supply；3 feet of U8 connect one end of C22；The one termination 3.3V power supply ground of C22；2 feet of U8 connect the negative pole of diode D15；The negative pole of diode D15 connects the ground of 3.3V power supply；2 feet of the one termination U8 of inductance L4；The other end of the other end connecting resistance R34 of inductance L4；The other end of the one termination inductance L4 of electric capacity C21；Another termination 3.3V power supply ground of electric capacity C21；12 feet of amplifier U3 are connected with one end of resistance R7 and resistance R3；The other end of resistance R7 is connected with the negative pole of voltage reference U1；The positive level ground connection of voltage reference U1；The other end of resistance R7 is connected with one end of resistance R6；One end of resistance R9 is connected with one end of resistance R12；The other end of resistance R9 is connected with 13 feet of amplifier U3；10 feet of amplifier are connected with one end of resistance R18；The other end of resistance R18 is connected with one end of resistance R19；The other end of resistance R19 is connected with one end of resistance R21；The other end of resistance R21 is connected with resistance R20；The other end of resistance R20 is connected with 8 feet of amplifier U3；One end of one first lunar month resistance R13 of electric capacity C11 connects；The other end of resistance R13 is connected with one end of the other end of C11 and R8；One end of the other end of resistance R8 and electric capacity C6, C7, C8, C9, C4 connects and diode D7, D8 positive pole and diode D9, D20 negative pole connect；The other end of D7 is connected with the S pole of metal-oxide-semiconductor Q1；The D pole of Q2 connects in succession with the negative of diode D4；The negative pole of diode D8 is connected with the positive pole of diode D4；The positive pole of diode D20 is connected with one end of resistance R51；The other end of resistance R51 is connected with the emitter stage of audion Q20；The base stage of Q20 is connected with the positive pole of diode D20；The colelctor electrode of Q20 is connected with one end of resistance R50；The D pole of metal-oxide-semiconductor Q5 is connected with the positive pole of diode D9 and one end of inductance L1 connects；The S pole of metal-oxide-semiconductor Q5 is connected to ground；The G pole of metal-oxide-semiconductor Q5 is connected with 4,6,8,10,12 feet of Schmidt U2；2 feet of the 3 of U2,5,9,11,13 feet and U2 connect；1 foot of U2 and one end of resistance R50 connect；The negative pole of diode D2 is connected with the positive pole of diode D5；The positive pole of diode D2 is connected with the positive pole of diode D3；The negative pole of diode D3 is connected with the positive pole of diode D6；The negative pole of diode D6 is connected with the negative pole of diode D5；8 feet of switching power source chip U4 are connected with one end of resistance R10；The other end of resistance R10 is connected with 6 feet of U4 and one end of inductance L2；7 feet of U4 are connected with one end of resistance R10；5 feet of U4 are connected with one end of resistance R17, resistance R11；3 feet of U4 are connected with one end of electric capacity C14；The other end of electric capacity C14 is connected with 4 feet of U4；2 feet of U4 are connected with 4 feet of U4；The positive pole of another first lunar month D10 of inductance L2 connects；The negative pole of D10 is connected with the other end of resistance R11；The other end of resistance R11 is connected with one end of electric capacity C12;The other end of electric capacity C12 is connected with 4 feet of U4.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of pre-amplification circuit is: one end of 5 foot connecting resistance R4 of amplifier U2；One end of 6 foot connecting resistance R5 of amplifier and one end of R7 and one end of C2；The other end of another termination capacitor C2 of resistance R4 and one end of resistance R8；The other end of the other end connecting resistance R7 of resistance R8；7 feet of another termination amplifier U2 of resistance R5；5 feet of amplifier connect one end of electric capacity C3；Another termination instrument of electric capacity C3 amplifies output 6 foot of U3；The one end of the 1 foot connecting resistance R3 that instrument is amplified；Instrument amplifies the other end of the 8 foot connecting resistance R3 of U3；Instrument amplifies one end of the 2 foot connecting resistance R6 of U3；One end of another termination capacitor C4 of resistance R6；One end of another termination capacitor C1 of electric capacity C4；The other end ground connection of electric capacity C1；Instrument amplifies one end of the 3 foot connecting resistance R9 of U3；One end of another termination capacitor C6 of resistance R9；One end of 5 foot connecting resistance R2 of AD conversion U1；5 feet of the one termination U1 of resistance R1.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, it is characterized in that: 4 ~ 20mA output circuit uses PWM type DA to be changed by U/I, and the annexation of 4 ~ 20mA output circuit is: a terminating resistor R36 of electric capacity C20 and resistance R31 and 13 feet of schmidt trigger U5F；One end of another termination capacitor C17 of resistance R31 and one end of electric capacity C18；One end of the other end connecting resistance R33 of electric capacity C17 and one end of resistance R35；The other end of the other end connecting resistance R33 of electric capacity C18 and the positive input terminal of amplifier U10A；12 feet of another termination Schmidt trigger U5F of resistance R35；The negative electrode of benchmark U9 connects with one end of electric capacity C18；The other end of the anode connecting resistance R36 of benchmark U9；The negative electrode of the one termination benchmark U9 of electric capacity C19；The negative electrode of stabilivolt D14 connects the negative electrode of benchmark U9；One end of the anode connecting resistance R38 of stabilivolt D14；The anode of another termination benchmark U9 of resistance R38；The anode of the one termination stabilivolt D14 of resistance R39 and 4 feet of amplifier U10A；The other end ground connection of resistance R39；8 feet of amplifier U10A meet 24V；The drain electrode of the negative input termination metal-oxide-semiconductor Q15 of amplifier；The grid of the output termination metal-oxide-semiconductor Q15 of amplifier U10A；The source electrode of metal-oxide-semiconductor Q15 connects the anode of diode D16；One end of the negative input end connecting resistance R32 of amplifier；The negative electrode of another termination stabilivolt D14 of resistance R32；The negative electrode of stabilivolt D14 connects the negative electrode of Light-Emitting Diode D13；The anode of light emitting diode D13 meets 24V.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of RS485 telecommunication circuit is: one end of the 1 foot connecting resistance R40 of 485 chip U11；2 feet of 485 chip U11 and 3 feet are connected；The 5 foot ground connection of 485 chip U11；One end of the foot 6 foot connecting resistance R42 of 485 chip U11 and the negative electrode of transient state pipe D17；The other end ground connection of resistance R42；The plus earth of transient state pipe D17；One end of the 7 foot connecting resistance R41 of 485 chip U11 and the negative electrode of transient state pipe D18；Another termination 5V of resistance R41；The plus earth of transient state pipe D18.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of HART communication circuit is: 1 foot of HART chip and 2 feet are connected 3.3V；3 foot ground connection of HART chip；The one termination 3.3v of electric capacity C2；The other end ground connection of electric capacity C2；7 feet of HART chip connect one end and one end of electric capacity C3 of crystal oscillator；8 feet of HART chip connect the other end and one end of electric capacity C4 of crystal oscillator；The other end ground connection of electric capacity C3；The other end ground connection of electric capacity C4；9 feet of HART chip, 10 foot ground connection；11 feet of HART chip meet 3.3V；11 feet of HART chip connect one end of electric capacity C5；The other end ground connection of electric capacity C5；One end of 12 foot connecting resistance R4 of HART chip；Another termination capacitor C10 of resistance R4 and the positive input terminal of amplifier U2 and；The other end ground connection of electric capacity C10；13 feet of HART chip connect electric capacity C6, C7, one end of resistance R2；The other end ground connection of electric capacity C6, C7；Another termination 14 feet of HART chip, resistance R1, one end of electric capacity C8 of resistance R2；The other end ground connection of resistance R1；Another termination capacitor C9 of electric capacity C8, one end of resistance R3；The other end ground connection of electric capacity C9；One end of another termination capacitor C11 of resistance R3；15 feet of HART chip, 16 feet, 17 feet, 18 foot ground connection；Electric capacity C1, C14 mono-terminates 3.3V；Electric capacity C1, C14 other end ground connection；2 foot ground connection of amplifier U2；5 feet of amplifier U2 connect 3.3V and one end of electric capacity C12；The other end ground connection of electric capacity C12；The output of negative input termination amplifier U2 of amplifier U2；The output of amplifier connects one end of electric capacity C13.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of governor circuit is: the 22 of single-chip microcomputer U4,53,63 feet are connected with one end of electric capacity C8 and one end of electric capacity C9;The other end of electric capacity C8 is connected with one end of crystal oscillator Y1；The other end of crystal oscillator Y1 is connected with the other end of electric capacity C9；Level is practiced in one end of 20 feet of single-chip microcomputer and electric capacity C11；The other end ground connection of electric capacity C11；Another termination VCC of resistance R14；The outfan of voltage stabilizing chip V1 is connected with one end of electric capacity；The other end of electric capacity is connected with the common port of voltage stabilizing chip V1；The input termination 5V of voltage stabilizing chip V1, V2, V3；The other end of the output capacitor C10 of voltage stabilizing chip V2；The one termination common port of electric capacity C10；The outfan of the one termination voltage stabilizing chip V3 of electric capacity C14；The common port of another termination voltage stabilizing chip V3 of electric capacity C14；One end of the 6 foot connecting resistance R12 of operational amplifier U5；Another termination+5V of resistance R12；One end of 6 foot connecting resistance R10 of amplifier U5；Outfan 7 foot of another termination amplifier of resistance R10；3 feet of amplifier U5 and 5 foot ground connection；The other end of 2 foot connecting resistance R15 of amplifier；Another termination+3V of resistance R15；One end of 2 foot connecting resistance R13 of amplifier；1 foot of another termination amplifier of resistance R13；8 feet of single-chip microcomputer U30 connect one end of electric capacity C31；The other end ground connection of electric capacity C31；9 feet of Schmidt trigger U8 connect one end of electric capacity C17；The other end ground connection of electric capacity C17；One end of the 9 foot connecting resistance R20 of U8；Another termination the 1 of U8,3,5,11,13 foot of resistance R20 also connects 8 feet of U8 simultaneously；The 2 of U8,4,6,10,12 feet connect one end of electric capacity C20；The negative pole of diode D2 connects the negative pole of diode D3 and connects one end of electric capacity C22, C23 simultaneously；The positive pole of diode D2 connects the negative pole of diode D4；The positive pole of diode D4 connects the positive pole of diode D5；The negative positive pole meeting D3 of diode D5；One end of electric capacity another termination capacitor C24 of C22；The other end of another termination capacitor C25 of electric capacity C24；The other end of one termination capacitor C23 of electric capacity C25；One end of electric capacity C13 one end resistance R16；The other end of the other end connecting resistance R16 of electric capacity C13；The input positive pole of another termination optocoupler U6 of resistance R16；The input minus earth of optocoupler U6；The colelctor electrode of optocoupler U6 meets 3.3V；The emitter stage of optocoupler U6 connects the colelctor electrode of optocoupler U7；The grounded emitter of optocoupler U7；The input positive pole of optocoupler U7 meets VCC；One end of the negative pole connecting resistance R17 of optocoupler U7；One end of another termination capacitor C15 of resistance R17；The input negative pole of another termination optocoupler of electric capacity C15；The input positive pole of optocoupler U9 and one end of one end of electric capacity C16 and resistance R18 connect；The resistance R18 other end connects with the other end of electric capacity C16 and is connected with optocoupler U7 negative pole；The other end of resistance R18 is connected with one end of resistance R19 and one end of electric capacity C18；The other end of electric capacity C18 and resistance R19 connects；The input minus earth of optocoupler U9；Optocoupler U9 output colelctor electrode connects 3.3V optocoupler U9 output emitter stage and connects optocoupler U10 colelctor electrode；U10 grounded emitter；The colelctor electrode of optocoupler U11 meets VCC；The emitter stage of U11 and the colelctor electrode of optocoupler U12 connect；The grounded emitter of U12；The input positive pole of U11 connects one end of R21 and connects；The input positive pole of U11 is connected with C19 one end；The input positive pole of U12 connects 3.3V, input negative pole connecting resistance R22 one end and electric capacity C21 one end；The resistance R22 other end is connected with the electric capacity C21 other end.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of frequency output circuitry is: optocoupler U33 input positive pole is connected with one end of resistance R61；Resistance R61 another termination 3.3V.
High-accuracy electromagnetic flowmeter based on fast Fourier transform the most according to claim 1, is characterized in that: the annexation of alarm output circuit is: the input positive pole of optocoupler U25 is connected with resistance R87 one end；Resistance R87 another termination 3.3V.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201620196413.6U CN205483107U (en) | 2016-03-15 | 2016-03-15 | High accuracy electric -magnetic flow meter based on fast fourier transform |
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| CN201620196413.6U CN205483107U (en) | 2016-03-15 | 2016-03-15 | High accuracy electric -magnetic flow meter based on fast fourier transform |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105698881A (en) * | 2016-03-15 | 2016-06-22 | 江苏华海测控技术有限公司 | High-precision electromagnetic flowmeter based on fast Fourier transform |
| CN109624209A (en) * | 2018-12-07 | 2019-04-16 | 重庆电子工程职业学院 | Injection molding apparatus is used in a kind of processing of communication equipment shell |
-
2016
- 2016-03-15 CN CN201620196413.6U patent/CN205483107U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105698881A (en) * | 2016-03-15 | 2016-06-22 | 江苏华海测控技术有限公司 | High-precision electromagnetic flowmeter based on fast Fourier transform |
| CN109624209A (en) * | 2018-12-07 | 2019-04-16 | 重庆电子工程职业学院 | Injection molding apparatus is used in a kind of processing of communication equipment shell |
| CN109624209B (en) * | 2018-12-07 | 2020-07-31 | 重庆电子工程职业学院 | Injection molding device is used in processing of communication equipment casing |
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