CN101782407A - Digital vortex street/precession flowmeter powered by battery - Google Patents
Digital vortex street/precession flowmeter powered by battery Download PDFInfo
- Publication number
- CN101782407A CN101782407A CN 201010112213 CN201010112213A CN101782407A CN 101782407 A CN101782407 A CN 101782407A CN 201010112213 CN201010112213 CN 201010112213 CN 201010112213 A CN201010112213 A CN 201010112213A CN 101782407 A CN101782407 A CN 101782407A
- Authority
- CN
- China
- Prior art keywords
- frequency
- chip microcomputer
- voltage
- signal
- fft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
The invention relates to a digital vortex street/procession flowmeter powered by battery, comprising a piezoelectric sensor, a single operational amplifier differential charge amplifier, a voltage amplifier, a lowpass filter, a voltage follower, a band-pass filter group, a band-pass selection switching circuit, a wave shaping circuit, a singlechip, a man-machine interface circuit, a two-stage voltage conversion circuit, a controllable constant current source, a temperature sensor, a pressure sensor, a differential amplifier and a 16-bit A/D converter. Power supply of system is designed to be in two-stage conversion. Low power consumption singlechip is adopted to carry out less point rapid Fourier transform, periodic map analysis is realized, and frequency value of vortex street/procession signal is determined; a hardware band-pass filter group is designed, concrete band-pass filter is selected according to map analysis result, and optimal filtering is carried out; and the operational amplifier in the ungated band-pass filter is in unenabled state. Temperature and pressure compensation is set as intermittent sampling mode. At the sampling interval, a single-pole double-throw switch is utilized to cut off upper terminal voltage supply of the constant current source.
Description
Technical field
The present invention relates to field of flow detection, be a kind of low power consumption digital vortex street/precession flowmeter, particularly a kind of is the battery powered vortex street/precession flowmeter signal processing system of employing that core, power spectrum analysis combine with the hardware band-pass filter group with single-chip microcomputer (MCU).
Background technology
Chinese invention patent has been announced a kind of improved low-power and two-wire vortex shedding flowmeter (Xu Kejun, Liu Sanshan, Liu Jiaxiang, Luo Qinglin, Zhu Zhihai. improved low-power and two-wire vortex shedding flowmeter, application patent of invention, 200810246107.9, the applying date: 2008.12.22.).Low-power and two-wire vortex shedding flowmeter after this improvement comprises piezoelectric sensor, differential charge amplifier, voltage amplifier, programmable amplifier, low-pass filter, voltage follower, bandpass filter group, the logical selected on-off circuit of band, peak detection circuit, shaping circuit, single-chip microcomputer, man-machine interface circuit, 4～20mA output and electric power management circuit, constant current source, temperature sensor, pressure transducer, differential amplifier, 16 analog to digital converters.The mode that adopts the FFT spectrum analysis of counting less to combine with the analog band-pass filter group is handled the vortex street sensor signal, adopt the frequency measurement method of precision such as multicycle, possess temperature and pressure compensating circuit and function, output 4～20mA DC current, two-wire system work.Low-power and two-wire vortex shedding flowmeter range ratio, measuring accuracy and antijamming capability after the improvement all increase substantially.This low-power and two-wire vortex shedding flowmeter still, does not have external power source or draws the power supply expense than higher with lead in some site of deployment with the work of 14V-36V DC-voltage supply, at this moment just needs with battery-powered vortex shedding flow meter.The vortex precession flowmeter close with the vortex shedding flow meter measuring principle also is to adopt piezoelectric sensor output and the proportional frequency signal of flow, is commonly used to the measurement gas flow, also usually adopts the powered battery mode.For battery powered vortex street/precession flowmeter, do not require and possess the output of 4-20mA electric current, also low slightly than common power supply mode to the requirement of measuring accuracy, require to show instantaneous and integrated flux, go forward side by side trip temperature and pressure compensation, requiring can continuous working more than a year and a half with a battery that saves 3.6V, 6.5 ampere-hours.Can work a year and a half in order to realize powered battery, this type of flowmeter all is the modes that adopt frequent dormancy at present, specifically, flowmeter is not to count the pulse that flow produces all the time, but behind the certain interval of time, the pulse of meter a period of time is again behind the certain interval of time, count the pulse of a period of time again ...Promptly use instantaneous delivery in a certain very short time section as the average discharge of a long-time section.Like this, when fluctuations in discharge is bigger, will produce very big measuring error.Simultaneously, there is the defective of little, the anti-on-the-spot vibration interference ability of range ratio in the processing mode of the amplification, filtering, shaping and the step-by-step counting that all are to use of this type of flowmeter at present.
Summary of the invention
Defective at current battery power supply vortex street/precession flowmeter, patent basis of the present invention is to the requirement of the precision and the range ratio of powered battery vortex street/precession flowmeter, on the basis of having applied for a patent, further improve circuit and algorithm: behind (1) certain paths according to actual vortex signal frequency select tape bandpass filter group, all the other seven passages no longer carry out filtering; (2) consider that in some application scenario, temperature and pressure changes slower, utilize the intermittent sampling pattern to replace the real-time sampling pattern, and the controlled constant current source of design loop break-make, to reduce the power consumption of system; (3) be directed to the circuit of low-power consumption two-wire system design of operating modes, further reduce current drain.
Advantage of the present invention is: the cycle collection of illustrative plates combines with the analog band-pass filter group, and flow sensor is carried out optimum filtering, realizes step-by-step counting accurately; All the time flow pulses is counted, even if when bigger variation takes place flow, also can guarantee measuring accuracy preferably; Adopt the powered battery of 3.6 volts at a joint, 6.5 ampere-hours, this low-power consumption, digital vortex street/precession flowmeter can be worked time a year and a half at least.
Description of drawings
Fig. 1 is the system hardware block diagram.
Fig. 2 is single amplifier differential charge amplifier circuit theory diagrams.
Fig. 3 is a charge amplifier output signal conditioning circuit schematic diagram.
Fig. 4 is a dividing potential drop follow circuit schematic diagram.
Fig. 5 is the biasing circuit schematic diagram.
Fig. 6 is bandpass filter group 1 circuit theory diagrams.
Fig. 7 is bandpass filter group 2 circuit theory diagrams.
Fig. 8 is that wave filter is selected and pulse shaping circuit figure.
Fig. 9 is the gating circuit figure of DC/DC.
Figure 10 is digital 2.7V voltage conversion circuit figure.
Figure 11 is simulation 2.5V voltage conversion circuit figure.
Figure 12 is the power down protection circuit diagram.
Figure 13 is impulse output circuit figure.
Figure 14 is controlled constant current source, temperature sensor and pressure sensor interface circuit diagram.
Figure 15 is pressure transducer differential amplifier circuit figure.
Figure 16 is 16 analog-digital converter circuit figure.
Figure 17 is single chip circuit figure.
Figure 18 is keyboard input circuit figure.
Figure 19 is a LCD display module wiring schematic diagram.
Figure 20 is outer watchdog circuit figure.
Figure 21 extends out the FRAM circuit diagram.
Figure 22 is the system software block diagram.
Figure 23 is system's master monitor process flow diagram.
Figure 24 is system's pulse capture theory diagram.
Figure 25 is a system frequency estimation process flow diagram.
Figure 26 is a system filter device channel selecting process flow diagram.
Figure 27 is the flow system flow calculation flow chart.
Figure 28 is system's keyboard scan process flow diagram.
Embodiment
The present invention is further illustrated below in conjunction with accompanying drawing.
Design philosophy of the present invention is: adopt the method for digital spectrum analysis combined belt bandpass filter, improved antijamming capability, measuring accuracy and the range ratio of instrument, and by the temperature and pressure compensation, expanded the scope of application of instrument.Yet according to battery powered requirement, series is wanted and can be worked a year and a half.If adopt the powered battery of 3.6 volts at a joint, 6.5 ampere-hours, the average current of system consumption must be lower than 500uA, and this is far smaller than the single-chip microcomputer current drain of operation and signal condition and compensating circuit fully.So, adopted following effective measures to reduce the power consumption of system: (1) according to the duty of battery virtual voltage and single-chip microcomputer, realizes the real-time switching of buck DC to dc converter (DC/DC) and low pressure difference linearity stabilized voltage supply (LDO) in the first order voltage transitions; In order to reduce simulation part power consumption, utilize LDO to realize second level voltage transitions, further reduce the supply voltage of simulation part.(2) adopt the low-power scm fast Fourier transform (FFT) of counting less, performance period, atlas analysis was determined the frequency values of vortex signal; Design one group of hardware band-pass filter, its passband covers the frequency band of vortex street/precession vortex signal, selects concrete bandpass filter according to the spectrum analysis result, carries out optimum filtering; The operational amplifier in the bandpass filter of gating is not in not enabled state, reduces the power consumption of system.(3) temperature and pressure compensation is set to the intermittent sampling pattern.In the gap of sampling, the upper terminal voltage of utilizing single-pole double-throw switch (SPDT) (SPDT) to cut off constant current source is supplied with, and reduces the power consumption of system.
The general structure of system of the present invention as shown in Figure 1.System of the present invention is by piezoelectric sensor, single amplifier differential charge amplifier, voltage amplifier, low-pass filter, voltage follower, bandpass filter group, the logical selected on-off circuit of band, shaping circuit, single-chip microcomputer, man-machine interface circuit, two-stage voltage conversion circuit, controlled constant current source, temperature sensor, pressure transducer, differential amplifier, 16 analog to digital converters (ADC).
The course of work of system of the present invention is: from the faint charge signal of piezoelectric sensor output, at first change it into voltage signal through charge amplifier, because amplitude is very little, so, after through the passive low-pass filtering of one-level, pass through one-level limiting voltage amplifier again.Signal after the amplification is through low-pass filter, and the high frequency interference in the filtered signal is then by voltage follower (impact damper) output 2 road signals.Behind the 1 road signal process dividing potential drop, the follow circuit, ADC sampling and conversion by single-chip microcomputer carries become digital quantity.The FFT that single-chip microcomputer is counted less to signal does power spectrum analysis, obtains the frequency values of signal, comes the passage of select tape bandpass filter group, enables the operational amplifier of respective channel.The 2 road signal is delivered to the bandpass filter group, carries out filtering; Spectrum analysis result by single-chip microcomputer decides the filtered signal in certain road of output.Carry out shaping delivering to the shaping circuit of being made up of comparer through the output signal of bandpass filter group, the signal after the shaping is delivered to the timer input end of single-chip microcomputer, and the employing acquisition mode utilizes precision methods such as multicycle to carry out frequency counting.According to count results, single-chip microcomputer is presented at flow information on the LCD.In order to reduce the average power consumption of system, single-chip microcomputer is provided with park mode, and under this pattern, the single-chip microcomputer consumed current only is 5uA.Single-chip microcomputer is whenever finished one-shot measurement, dormancy 3s.The power supply of system is designed to the two-stage conversion, and in first order transfer process, conversion efficiency under different situations respectively has quality according to voltage-dropping type DC/DC and LDO, has designed logic determines and has selected circuit.When supply voltage was higher than 3.3V or single-chip microcomputer and moves fully, under the current loading of system requirements, the conversion efficiency of voltage-dropping type DC/DC will be higher than LDO, therefore selects for use voltage-dropping type DC/DC to change; Otherwise, then select for use LDO to change.In the transfer process of the second level, utilize LDO to reduce the supply voltage of simulation part, saved power consumption.The temperature and pressure compensating module of system adopts the intermittent sampling pattern, in the gap of sampling, utilizes SPDT (Single-Pole Double-Throw, single-pole double-throw (SPDT)) to supply with from the disconnected constant current source of the upper end-grain cutting of voltage, thereby has reduced system power dissipation.By above-mentioned measure, make that the average current of system is 460uA, meet battery powered designing requirement.
As shown in Figure 2, the vortex street/precession quantity sensor, the charge signal that is piezoelectric sensor output is via amplifier U1A, capacitor C 1, C4, C7, C11, C12, single amplifier differential charge amplifier that resistance R 1, R8, R11 form is amplified, wherein, C1, C12 are feedback capacities, have determined the enlargement factor of charge amplifier.Bias voltage Vref among Fig. 1 and other figure is provided by biasing circuit shown in Figure 5.Biasing circuit is by U1B, resistance R 12, R14, and capacitor C 13 is formed, and 1.235V is provided DC voltage.
Signal after amplifying, is delivered to by amplifier U2A after the removal flip-flop by capacitance C5, resistance R 4, R5, R2, R9, and capacitor C 6, C2, C9, the limiting voltage amplifier that diode D1, D2 form, as shown in Figure 3.Among the figure, resistance R 4, R5 and capacitor C 6 have constituted the passive low-pass filtering of one-level.Resistance R 2 is the U2A feedback resistance, and the ratio of itself and resistance R 4, R5 sum is the enlargement factor of amplifying circuit.Capacitor C 2, resistance R 2 and amplifier U2A have constituted the one-level active low-pass filter again.Resistance R 9 is a balance resistance, the offset voltage of balance amplifier two input ends.The relation that the amplitude of considering vortex street/precession quantity sensor output signal becomes with frequency square, and the frequency range broad of vortex street/precession vortex signal are so the signal amplitude variation range is very big.Saturated in order to prevent amplifier output, diode D1, D2 constitute double limiting, with the amplitude limitation of signal communication component in its conduction voltage drop.Signal behind limiting amplifier is delivered to low-pass filter and voltage follower, as shown in Figure 3.Low-pass filter is by amplifier U2B, capacitor C 3, C8, and resistance R 3, R6, R7, R10 form.Voltage follower is by amplifier U3A, and capacitor C 10 constitutes.Low-pass filter adopts multiple feedback arrangement, mainly be because this structure to have parameter drift sensitivity less, and the circuit scale of realizing is moderate.The output of voltage follower is divided into 2 the tunnel, and the 1 the tunnel through behind the dividing potential drop follow circuit, delivers to the P6.3/A3 pin of single-chip microcomputer, and the laggard line period atlas analysis of analog to digital converter (ADC) sampling that is carried by single-chip microcomputer is as Fig. 4 and shown in Figure 17.The dividing potential drop follow circuit is made of resistance R 13, R15 and amplifier U3B, and it is compressed to vortex street/precession vortex signal amplitude scope in the AD reference voltage of single-chip microcomputer.The 2 the tunnel directly delivers to the bandpass filter group carries out filtering, as shown in Figure 6 and Figure 7.
Though vortex street/precession quantity sensor signal has passed through foregoing low-pass filter, some high-frequency signals are by filtering.But, because the variation range broad of vortex street/precession vortex signal frequency, from 0.5Hz to 3.7KHz.In this frequency band range, may comprise vortex street/precession amount signal frequency, mechanical vibration frequency, flow field turbulent noise frequency and other noise frequency.If this signal is directly carried out shaping and counting,, make measurement result bigger error occur because various The noise are easy to cause the false triggering of shaping circuit.At this problem, system design of the present invention one group of analog band-pass filter, comprise a low-pass filter and 7 bandpass filter, as shown in Figure 6 and Figure 7.Wherein, low-pass filter is by amplifier U4A, capacitor C 16, C21, resistance R 17, R21, R22, R26, decoupling capacitance C14 constitutes, and for the signal phase that keeps each passage is identical, has added reverse follow circuit before low-pass filter, by amplifier U4B, resistance R 16, R20, R27, R89 constitute.The 1st bandpass filter be by amplifier U4D, capacitor C 26, C27, C28, and resistance R 31, R38, R41, R90, amplifier U4C, capacitor C 23, C31, resistance R 30, R34, R35, R40 constitute; The 2nd bandpass filter be by amplifier U5B, capacitor C 36, C39, C40, and resistance R 45, R52, R55, R91, amplifier U5A, capacitor C 35, C43, resistance R 44, R48, R49, R54, decoupling capacitance C33 constitutes; The 3rd bandpass filter be by amplifier U5D, capacitor C 46, C49, C50, and resistance R 59, R66, R69, R92, amplifier U5C, capacitor C 45, C53, resistance R 58, R62, R63, R68 constitute; The 4th bandpass filter be by amplifier U6D, capacitor C 47, C51, C52, and resistance R 60, R67, R70, R93, amplifier U6C, capacitor C 48, C54, resistance R 61, R64, R65, R71 constitute; The 5th bandpass filter be by amplifier U6B, capacitor C 37, C41, C42, and resistance R 46, R53, R56, R94, amplifier U6A, capacitor C 38, C44, resistance R 47, R50, R51, R57, decoupling capacitance C34 constitutes; The 6th bandpass filter be by amplifier U7D, capacitor C 24, C29, C30, and resistance R 32, R39, R42, R95, amplifier U7C, capacitor C 25, C32, resistance R 33, R36, R37, R43 constitute; The 7th bandpass filter be by amplifier U7B, capacitor C 17, C19, C20, and resistance R 18, R25, R28, R96, amplifier U7A, capacitor C 18, C22, resistance R 19, R23, R24, R29, decoupling capacitance C15 constitutes.The circuit structure of these 7 bandpass filter is identical, parameter is different, thereby passband is different, but interconnect, and covers the frequency band range of vortex shedding flow meter, and has certain overlapping between adjacent passband.Realize 1 bandpass filter by 1 Hi-pass filter and 1 low-pass filter, the amplitude versus frequency characte than single amplifier bandpass filter is good like this, and the amplitude versus frequency characte of the passband part that promptly forms like this is more smooth, and cut-off region is decayed sooner.Consider the scope of the frequency range of whole vortex signal, if go filtering, poor effect with one group of bandpass filter group at 0.5Hz to 3700Hz, so, design some groups of bank of filters at different situations, so both had certain versatility and interchangeability, guaranteed to have filter effect preferably again.For example, design the parameter of 1 group of bandpass filter group at the liquid flow measurement of 15mm to 200mm bore, its frequency of operation covers 1Hz to 500Hz; Design the parameter of 1 group of bandpass filter at the gas flow measurement of 25mm to 150mm bore, its frequency of operation covers 19Hz to 2300Hz.The concrete output signal of which wave filter of selecting is carried out shaping and counting, by single-chip microcomputer vortex signal is carried out results of spectral and decides.Be that single-chip microcomputer carries out power spectrum analysis to the vortex street/precession vortex sensor signal that collects, determine the scope of vortex signal; In view of the above, determine to carry out shaping and counting, can farthest eliminate of the influence of various noises like this, avoid false triggering, guarantee the precision of counting vortex street/precession vortex signal with the signal after which band-pass filter.
8 wave filters in the bandpass filter group, the amplifier in each passage enable control by the EN1 to EN7 of single-chip microcomputer respectively, and promptly low pass ENO enables the amplifier U4A in the low-pass filter, U4B; EN1 enables amplifier U4C, the U4D in the 1 tunnel bandpass filter; EN2 enables amplifier U5A, the U5B in the 2 tunnel bandpass filter; EN3 enables amplifier U5C, the U5D in the 3 tunnel bandpass filter; EN4 enables amplifier U6C, the U6D in the 4 tunnel bandpass filter; EN5 enables amplifier U6A, the U6B in the 5 tunnel bandpass filter; EN6 enables amplifier U7C, the U7D in the 6 tunnel bandpass filter; EN7 enables amplifier U7A, the U7B in the 7 tunnel bandpass filter.Resistance R 89, R90, R91, R92, R93, R94, R95, R96 are pull down resistor.Bandpass filter is at every turn according to the spectrum analysis of the single-chip microcomputer wherein a certain road of gating as a result, its output signal representative vortex flowmeter signals, and be subjected to disturbing effect little., the input signal of other passage also conducts to wave filter output by backfeed loop respectively.System of the present invention selects for use 8 to select 1 multi-way switch U14, as shown in Figure 8.8 input ends of this device link to each other with 8 passages of bandpass filter group respectively, and common port and output switching terminal 3 link to each other with the input end 3 of comparer U15 by resistance R 86.Among Fig. 8,3 control line A, the B of U14, C link to each other with I/O mouth P8.0, P7.3, the P7.2 of single-chip microcomputer respectively, as shown in figure 17.U14 comes the corresponding passage of gating according to the level of 3 tunnel control pins, promptly come the corresponding passage of gating according to the single-chip microcomputer results of spectral, and the passage of gating matches in this passage and the bandpass filter group.By gating signal is through filtered, as to contain minimum noise vortex signal, sends into comparer U15 and carries out shaping, exports the square wave of rule, sends into the P1.0 of single-chip microcomputer again, counts.Compare with common Schmidt trigger, the comparer here can be adjusted threshold voltage, and waveform will surpass threshold value ability trigger pulse, has stronger antijamming capability.
System of the present invention adopts the single-chip microcomputer MSP430F5418 of TI company for handling core, as shown in figure 17.Select the reason of this single-chip microcomputer to be, require system of the present invention to accomplish super low-power consumption, simultaneously, system uses the FFT computing when signal Processing, need jumbo SRAM, but extend out the power consumption that can increase system greatly, and the MSP430F5418 single-chip microcomputer has the SRAM of 16KB.
MSP430F5418 is the high-end product in the MSP430 series, it except the arithmetic logic unit that possesses super low-power consumption, also integrated abundant peripheral module.It mainly realizes low-power consumption by following three kinds of forms: have activity pattern and 6 kinds of low-power consumption modes, can select according to different needs, to reach purpose least in power-consuming; It also has unique clock system design, comprises fundamental clock (high-frequency clock and low-speed clock) system and DC (digital oscillator) clock system; In addition, it adopts vector to interrupt, and supports 64 interrupt sources, and waking CPU up with interrupt request only needs 5us.So, by suitable hardware design and reasonably programming, both can reduce system power dissipation, can make quick response to external event again.
MSP430F5418 is 16 single-chip microcomputers, uses present most popular reduced instruction set computer (RISC) structure, and a clock period can be carried out an instruction.Simultaneously, MSP430F5418 has adopted architectures such as general 32 hardware multipliers that only just have with DSP, DMA, has strengthened its data processing and arithmetic capability greatly, provides assurance for realizing the digital signal processing algorithm in the system of the present invention.
Peripheral hardware in MSP430F5418 the is integrated very abundant sheet mainly contains following functional module: 12 ADC of house dog, timer A, timer B, 32 hardware multipliers, 16 input channels, direct memory access (DMA) (DMA), 4 kinds of general serial communication interfaces, port one～port 8 (P1～P8) and basic timer.Though MSP430F5418 does not have integrated liquid crystal driver module,, add a slice liquid crystal driver module, can accomplish low-power consumption equally.
What MSP430F5418 single-chip microcomputer storer adopted is unified structure, the i.e. storage area that physically separates fully such as FLASH, RAM, peripheral module, special function register SFR etc., be arranged at same address space, like this, just can carry out byte or the visit of font formula to them with a group address, data bus, identical instruction.This organizational form and CPU adopt reduced instruction to coordinate mutually, the visit of peripheral module are not needed independent instruction, for the exploitation and the debugging of software are provided convenience.
System of the present invention has adopted the conversion of 2 level power supplies.Through the conversion of the 1st step voltage, obtain system digits part power supply by battery.In the 1st level power supply transfer process, in order to improve conversion efficiency, voltage-dropping type DC/DC and LDO are switched in real time according to the duty of actual cell voltage and single-chip microcomputer in system, and the DC/DC gating circuit as shown in Figure 9.Wherein, voltage detecting circuit comprises U1, resistance R 1, R2, R3 and capacitor C 3, and when voltage is lower than 3.3V, port 3 output low levels of U1.The running status of RUN signal indication single-chip microcomputer, high level represent that single-chip microcomputer is in complete running status, and low level represents that single-chip microcomputer is in dormant state.Voltage detection signal and single-chip microcomputer status signal, as the input of U2, its port 3 is exported the logic control level of DC/DC, is connected to the port 6 of voltage-dropping type DC/DC, as shown in figure 10.Resistance R 4 is a pull down resistor, and capacitor C 1, C2 are filter capacitor.
The conversion output voltage of the conversion output voltage of voltage-dropping type DC/DC a little more than LDO is set in the system,, can controls the duty of voltage-dropping type DC/DC and LDO simultaneously by the transition status of control voltage-dropping type DC/DC.When enabling voltage-dropping type DC/DC when changing, the output end voltage of LDO is higher than its internal reference voltage, thereby makes its internal logic judging unit cut off the power source conversion passage automatically; When not enabling voltage-dropping type DC/DC when changing, LDO changes output voltage, and this voltage does not form the filling electric current at the output terminal of voltage-dropping type DC/DC.Shown in Figure 10, be the 1st step voltage change-over circuit.Voltage-dropping type DC/DC power transfer module, comprise U4, capacitor C 11, C12, C4, C9, C10, resistance R 6, R7, R9 and inductance L 2, wherein, capacitor C 11, C12 are input filter capacitor, and capacitor C 9, C10 are output filter capacitor, capacitor C 4 can reduce output voltage ripple well, and the ratio of resistance R 7, R9 has been determined the output voltage of voltage-dropping type DC/DC.The LDO power transfer module comprises U5, capacitor C 16, C13, C14, C15 and resistance R 10, R11, and wherein, capacitor C 16 is an input filter capacitor, and capacitor C 14, C15 are output filter capacitor, and the ratio of resistance R 10, R11 has been determined the output voltage of LDO.
By reducing the supply voltage of simulation part, can reduce the power consumption of system within the specific limits.Therefore, utilize LDO to carry out the conversion of the 2nd step voltage in the system, as shown in figure 11, this part mainly comprises U3, inductance L 3, capacitor C 8, C5, C6, C7 and resistance R 5, R8.
As shown in figure 12, the power down protection circuit of system is by U6, and resistance R 12, R14, R13 and decoupling capacitance C17 form, and wherein, the ratio of resistance R 12, R14 has been determined the threshold voltage of power down protection.
The impulse output circuit that uses when Figure 13 shows that system calibrating.The circuit of optocoupler U7 both sides all adopts pulse output end 24V power supply, and the former limit circuit of optocoupler is by capacitor C 18, and resistance R 16, R20 and triode Q4 form.The secondary circuit of optocoupler is by capacitor C 19, resistance R 15, R17, R18, R19, R21, R22, and diode D1, D2, D3, D4, triode Q1, Q2, Q3 and toggle switch S1 form, and wherein, diode D1 is used to prevent the power supply reversal connection; Diode D2 is used to prevent power supply overvoltage and filter out power voltage overshoot; Toggle switch S1 is used for gating resistance R 21 or R22, thereby changes the amplitude of output pulse; Triode Q1 and Q3 form the Darlington transistor structure, have increased the current amplification factor between the basic emitter-base bandgap grading.When pulse input signal PulseIn was high level, pulse was output as low level; When input signal PulseIn was low level, pulse was output as high level.By adjusting the frequency of pulse input signal PulseIn, can adjust the frequency of output pulse.
As shown in figure 14, the temperature and pressure compensating circuit is by Low ESR SPDT chip U10,2.5V reference power supply U11, operational amplifier U8B, resistance R 88, R73, R74, R77, R75, R80, capacitor C 67, C56, C63, C59, C60, C62 and temperature and pressure compensation interface U12 form.U10 is by the P5.7 port output signal Temp_EN gating corresponding port of single-chip microcomputer, and as Figure 14 and shown in Figure 17, resistance R 88 is a pull down resistor, and when Temp_EN was high level, the NO of gating U10 and COM port were promptly connected constant current source; When Temp_EN is that low level is, the NC of gating U10 and COM port promptly disconnect constant current source.The ratio of resistance R 74 and R77 has been determined the normal phase input end voltage of operational amplifier U8B, and resistance R 80 has been determined the strength of current of constant current source.Capacitor C 63 is used for the differential mode interference of filtering operational amplifier U8B two input ends.Capacitor C 59 and resistance R 75 are used to compensate and isolate the output capacitance load of operational amplifier U8B.Capacitor C 60, C62 are filter capacitor.Temperature sensor two ends Temp+ and Temp-are connected to the input end of 16 analog to digital converter U13.Pressure transducer output signal Press+ and Press-, the process one-level is by operational amplifier U9A, U9B earlier, resistance R 72, R76, R78, R79, R82, R83, R85, capacitor C 57, C64, C61, C65, the differential amplifier that decoupling capacitance C55 forms amplifies, as shown in figure 15, and then, be connected to the input end of 16 analog to digital converter U13, as shown in figure 16.U13 is 16 ADC, and the analog signal conversion of temperature sensor and pressure transducer output is become digital signal, delivers to single-chip microcomputer by the I2C bus, for the temperature and pressure compensation of flow signal provides information.
The man-machine interface circuit of system of the present invention is made up of keyboard circuit and LCD display circuit, as Figure 18 and shown in Figure 19.Keyboard adopts simple nonencoded keyboard design, has arranged quadruple linkage altogether: set, be shifted, increase progressively and confirm, as shown in figure 18.Key assignments triggers capture interrupt by the P2 mouth in the GPIO mouth of single-chip microcomputer, and quadruple linkage takies P2.4, P2.3, P2.2, P2.1 respectively.Corresponding mouthful of line saltus step is high level when key is pressed.The LCD circuit of system of the present invention as shown in figure 19.Select the LCD of customization for use, be exclusively used in instrument such as flow, temperature, pressure, can 14 8 segmentation characters of double demonstration, and have alphabetical prompt and show.
Figure 20 shows that outer watchdog circuit, by extending out watchdog chip U1, reset key S1, decoupling capacitance C3 and resistance R 1, R2, R3 composition.The ratio of resistance R 2, R3 has been determined the voltage threshold that system's low level is reported to the police.The port 7 of U1 is connected to the RST pin of single-chip microcomputer, and port 6 is connected to the P1.7 of single-chip microcomputer, and port 5 is connected to the P2.0 of single-chip microcomputer, as shown in figure 17.
Shown in Figure 21 for extending out the FRAM circuit, comprise FRAM chip U4 and decoupling capacitance C11, C12.U4 and single-chip microcomputer adopt the SPI communications protocol, and the port one of U4,2,5,6 is connected to P3.3, P3.5, P3.4, the P3.0 of single-chip microcomputer respectively, as Figure 21 and shown in Figure 17.
Shown in Figure 22 is the system software The general frame; system software adopts modular design method, selects module, flow rate calculation module, temperature pressure compensation module and human-machine interface module to form by master monitor module, protection module, interrupt module, initialization module, frequence estimation module, bandpass filter.
Master monitor module among Figure 22 is the total activation program of total system software, by calling each program module, realizes the desired function of native system.Figure 23 is the master monitor process flow diagram of system, and it is a loop program, and after system powered on, master monitor moved automatically, and whole procedure will be carried out respective handling to each subroutine by the mode of setting.Its basic process is: system powers on, and immediately each functional module of single-chip microcomputer and man-machine interface variable is carried out initialization; System carries out FFT calculating for the first time then, selects corresponding bandpass filter passage; Single-chip microcomputer then is set enters low-power consumption mode, dormancy 3 seconds; Enter normal mode of operation then, send out and trigger lock-on signal, calculate pulsed frequency,, then carry out the temperature and pressure compensation if the temperature and pressure make-up time arrives, otherwise, integrated flux calculated; Then, whether determination frequency suddenlys change, if pulsed frequency is jumped out current filter frequencies bound, the frequency discontinuity sign is set, and carries out FFT again according to this sign and calculates; Then, refresh LCD, judge 30 seconds and regularly whether arrive, judge thus whether circulation is next time carried out FFT and calculated.
System of the present invention has used the LPM3 low-power consumption mode of MSP430F5418 single-chip microcomputer, periodically enters park mode by single-chip microcomputer is set, each dormancy 3 seconds, thus reduce system power dissipation; Single-chip microcomputer power consumption maximum considers that FFT calculating just to the frequence estimation of flow signal, does not need to calculate always during again because of calculating FFT, therefore system of the present invention is not that FFT calculating is all carried out in each circulation, calculate once but set 30s, a FFT computing is just carried out in promptly every circulation 10 times.As shown in figure 23, after system's power-up initializing, carry out the FFT calculating first time immediately, select corresponding bandpass filter, single-chip microcomputer is set then enters low-power consumption mode, regularly after 3 seconds, single-chip microcomputer withdraws from low-power consumption mode, come back to normal mode of operation, continue to carry out following program, after the loop ends, by having judged whether dormancy 10 times, if the dormancy number of times does not reach 10 times, single-chip microcomputer does not calculate FFT so, directly enters low-power consumption mode, if dormancy has reached 10 times, sign is set, and single-chip microcomputer carries out FFT and calculates, and reselects bandpass filter.
In the system of the present invention, use the method for precision such as multicycle to calculate pulsed frequency, thereby guaranteed the precision of calculating.For realizing the multicycle equal precision measurement, we are provided with timer A0 is vortex street/precession vortex signal pulse counter, it is the filler pulse counter that timer B is set, before carrying out pulsed frequency calculating, allow the PWM output unit of timer A0 send rising edge, timer A0 and timer B catch current counted number of pulses and filler pulse count value respectively, and the count difference value of catching according to adjacent twice these two timer calculates the pulsed frequency of vortex street/precession amount signal.As shown in figure 24, the clock of timer A0 is provided by the outside, i.e. outside pulse each, and the count value of timer A0 will increase by 1, so timer A0 counts the flow signal pulse; The clock of timer B is to be provided by single-chip microcomputer low frequency crystal oscillator (32768HZ), as the filler pulse counter.PWM output unit by timer A0 sends rising edge at every turn, triggers timer A0 and timer B count value is separately caught, and calculates timer A0 thus and catches difference Nx adjacent twice, reaches timer B and catches difference Ns adjacent twice, then
In the formula, Fs is the filler pulse frequency, and Ns is the filler pulse difference, and Nx is a flow signal pulse difference.
Among Figure 23, after pulse is caught in a triggering, one section time-delay (delay time decides according to the lower limit of flow) is set, because the multicycle equal precision measurement of adopting is sent out to trigger and is caught after the pulse, has only and waits until when next flow signal pulse arrives, just can capture pulse value, so after setting time-delay, captured data when guaranteeing to calculate pulse, guaranteed the pulse computation's reliability.
Figure 25 is the frequence estimation process flow diagram of system of the present invention.Signal is sampled, and the calculated rate value is according to this frequency values select tape bandpass filter.System of the present invention adopts the real number FFT that counts less to estimate the frequency of vortex street/precession vortex signal.At first the signal that sampling is obtained is judged its size, if sampling institute calling sequence amplitude is too little, then it is amplified, to improve the FFT operational precision; Then, sequence is carried out zero-mean handle, eliminate DC component; Then, sequence is carried out the FFT computing, calculate frequency.
The fast inadequately and limited problem of memory source for the arithmetic speed that overcomes single-chip microcomputer, following technical measures have been taked, on single-chip microcomputer real-time implementation real number FFT computing, and guaranteed the precision of algorithm: (1) adopts assembly language establishment real number FFT program, sequence to the sampling gained is carried out the odd even apportion, will be strange, even sequence is put into real part and the imaginary part array that FFT calculates respectively, carrying out common FFT then calculates, after calculating is finished, again the gained result is converted to the result of the FFT of actual point, can save the memory headroom of half by the method, improve arithmetic speed; (2) uniform data uses the Q13 fixed-point number to represent, promptly represent 1 data, most significant digit (left side first) is-symbol position, the size of 15 remaining bit representation data with 16, wherein, high 2 (left side second and the 3rd) is used for representing the integral part in the data, in calculating as safeguard bit, the fraction part in minimum 13 (the right 13) expression data, the data that sampling comes are placed on low 12 earlier, then, move to left 1, can reduce the EMS memory occupation amount like this; (3) adopt fixed-point number to calculate, its radix point of data that promptly uses in multiplication and additional calculation process is all fixed, to improve computing velocity; (4) in the FFT calculating process, every calculating through the one-level dish factor, its as a result maximum possible can enlarge 3 times, along with the increase of calculating progression, the data of representing with the Q13 form are certain to overflow, so, in computation process, must be shifted to data (moving to right), to prevent overflowing of data, but, in actual computation, be not that every grade of result calculated all can be overflowed, if this moment the result is shifted, will reduce the FFT precision of calculation results, because displacement diminishes data, promptly reduced the significance bit of fraction part, for this reason, earlier judge that whether this one-level result of calculation is greater than 1, when greater than 1 the time, just displacement just is not shifted less than 1.Calculate the power spectrum of signal by the FFT operation result,,, estimate the frequency of vortex flowmeter signals according to the peak power spectrum peak according to the energy principle that is dominant; At last, utilize the center of gravity correction method to carry out frequency spectrum and proofread and correct, improve the precision that vortex street/precession amount signal frequency is measured.According to the frequency of vortex street/precession amount signal, by the Single-chip Controlling multiplexer circuit, select bandpass filter corresponding to current vortex street/precession amount signal frequency, this bandpass filter is linked to each other with the shaping circuit of back.
Figure 26 is that the bandpass filter of system of the present invention is selected process flow diagram.The passband of 8 bandpass filter of design has covered the whole frequency range of vortex street/precession amount signal.In order to guarantee seamless switching, between the passband of adjacent filter lap is arranged; Simultaneously, when vortex street/when the precession vortex signal frequency is in adjacent passband edge, cause the frequent switching of bandpass filter easily, for avoiding conversion bandpass filter continually, the disposal route that bandpass filter is selected as shown in figure 26, during the frequency range of the bandpass filter that exceeds last time and select when frequency, just find out all bandpass filter that cover this frequency, select only wave filter then; If do not surpass current bandpass filter frequency band range, then do not switch.Concrete selection course is: when frequency does not surpass the bound of current filter transmission band, just still select current wave filter; When frequency just in time drops in the halved belt of two filter transmission bands, to select according to the point of crossing of these two filter transmission bands, promptly the joining of these two wave filter amplitude versus frequency charactes as a separatrix: when frequency is lower than the point of crossing, just select the wave filter of lower passband, be higher than the wave filter that upper passband is just selected in the point of crossing.
Figure 27 is the flow rate calculation process flow diagram.The flow rate calculation module is the result that pulsed frequency is calculated, and after treatment, calculates instantaneous delivery and integrated flux.According to the frequency computation part result, at first judge the flow rate calculation first time whether system powers on later, general flow rate calculation value for the first time is not too accurate, so, if calculate for the first time, be 0 with regard to the frequency of calculating is set, and deposit this frequency in formation; If not, judge that then whether pulsed frequency is less than the cutoff frequency that is provided with, if it is 0 that frequency just is set, and deposits this frequency in formation; Then judge the frequency calculated whether within the scope of current filter pass band, if, deposit this frequency in formation, if do not exist,, preserve the double just now frequency resultant of calculating just with whole formation zero clearing of depositing frequency; Then judge the whether double frequency jitter scope that exceeds setting of the frequency calculated, if, preserve the double just now frequency resultant of calculating just with whole formation zero clearing of depositing frequency; Then the frequency that is kept in the formation is sorted, find out the number of nonzero frequency, judge then whether the number of nonzero frequency surpasses 5, if, calculate the frequency of vortex street/precession amount signal with regard to the nonzero frequency in the direct average queue; If not, just find out the maximal value in the nonzero frequency in the formation, second largest value, minimum value, sub-minimum is removed these 4 in nonzero frequency values then, and the nonzero frequency of remainder is averaged, and calculates the frequency of vortex flowmeter signals; Then select instrument coefficient, calculate instantaneous delivery; Judge then whether the temperature pressure compensation time arrive,, then the instantaneous delivery that calculates is carried out the temperature and pressure compensation, calculate integrated flow then,, directly calculate integrated flow if do not arrive if arrived.Consider that temperature, pressure over time relatively slowly, all do not carry out the temperature and pressure compensation so system of the present invention is each circulation, but regularly carry out the temperature and pressure compensation, further reduce system power dissipation.
Figure 28 is the key scan process flow diagram.In the system of the present invention, single-chip microcomputer is in dormant state for a long time, thus use IO mouth as the button port with interrupt function, even guarantee that single-chip microcomputer under dormant state, also can respond button operation.The time of pressing by timer record button judge button belong to long by or short in operation.Detailed process is: when button is pressed, send rising edge, the value of record timer B this moment, when button unclamps, send negative edge, again the value of record timer B this moment, calculate this twice difference then, draw the time that button is pressed, judgement be long by or short in operation, carry out then corresponding long by or short subroutine of pressing.
Claims (7)
1. a battery powered digital vortex street/precession flowmeter comprises piezoelectric sensor, single amplifier differential charge amplifier, voltage amplifier, low-pass filter, voltage follower, bandpass filter group, the logical selected on-off circuit of band, shaping circuit, single-chip microcomputer, man-machine interface circuit, two-stage voltage conversion circuit, controlled constant current source, temperature sensor, pressure transducer, differential amplifier and 16 analog to digital converters; It is characterized in that:
From the faint charge signal of piezoelectric sensor output, at first change it into voltage signal through charge amplifier, after through the passive low-pass filtering of one-level, pass through one-level limiting voltage amplifier again; Signal after the amplification is through low-pass filter, and the high frequency interference in the filtered signal is exported 2 road signals by voltage follower then; Behind the 1 road signal process dividing potential drop, the follow circuit, analog to digital converter (ADC) sampling and conversion by single-chip microcomputer carries become digital quantity; Power spectrum analysis is done in the Fast Fourier Transform (FFT) that single-chip microcomputer is counted less to signal (FFT), obtains the frequency values of signal, comes the passage of select tape bandpass filter group, enables the operational amplifier of respective channel; The 2 road signal is delivered to the bandpass filter group, carries out filtering; Spectrum analysis result by single-chip microcomputer decides the filtered signal in certain road of output; Carry out shaping delivering to the shaping circuit of being made up of comparer through the output signal of bandpass filter group, the signal after the shaping is delivered to the timer input end of single-chip microcomputer, and the employing acquisition mode utilizes precision methods such as multicycle to carry out frequency counting; According to count results, single-chip microcomputer is presented at flow information on the LCD (LCD).
2. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: the power supply of system is designed to the two-stage conversion, in first order transfer process, according to buck DC to dc converter (DC/DC) and low pressure linear voltage regulator (LDO) conversion efficiency under different situations quality is arranged respectively, design logic is judged the selection circuit; When supply voltage was higher than 3.3V or single-chip microcomputer and moves fully, the conversion efficiency of voltage-dropping type DC/DC will be higher than LDO, selects for use voltage-dropping type DC/DC to change; Otherwise, then select for use LDO to change; In the transfer process of the second level, utilize LDO to reduce the supply voltage of simulation part, save power consumption.
3. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: the LPM3 low-power consumption mode that uses the MSP430F5418 single-chip microcomputer, by being set, single-chip microcomputer periodically enters park mode, each dormancy 3 seconds, thus reduce system power dissipation; Because single-chip microcomputer power consumption maximum when calculating FFT considers that FFT calculating just to the frequence estimation of flow signal, does not need to calculate, and therefore be not that FFT calculating is all carried out in each circulation, but 30s calculates once always; Detailed process is, after system's power-up initializing, carry out the FFT calculating first time immediately, select corresponding bandpass filter, single-chip microcomputer is set then enters low-power consumption mode, regularly after 3 seconds, single-chip microcomputer withdraws from low-power consumption mode, come back to normal mode of operation, continue to carry out following program, after the loop ends, by having judged whether dormancy 10 times, if the dormancy number of times does not reach 10 times, single-chip microcomputer does not carry out FFT calculating so, directly enters low-power consumption mode, if dormancy has reached 10 times, sign is set, and single-chip microcomputer carries out FFT and calculates, and reselects bandpass filter.
4. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: consider that temperature, pressure are over time relatively slowly, be not that the temperature and pressure compensation is all carried out in each circulation, but regularly carry out the temperature and pressure compensation, be the temperature and pressure compensating module of system, adopt the intermittent sampling pattern, in the gap of sampling, utilize single-pole double-throw switch (SPDT) (SPDT) to supply with, thereby reduce system power dissipation from the disconnected constant current source of the upper end-grain cutting of voltage.
5. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: the passband of one group of hardware band-pass filter has covered the frequency band of vortex street/precession vortex signal, select concrete bandpass filter according to the spectrum analysis result, carry out optimum filtering; The operational amplifier in the bandpass filter of gating is not in not enabled state, reduces the power consumption of system; Realize 1 bandpass filter by 1 Hi-pass filter and 1 low-pass filter, the amplitude versus frequency characte of its passband part is more smooth, and cut-off region is decayed sooner; In order to guarantee seamless switching and the frequent switching of avoiding bandpass filter, between the adjacent filter passband lap is arranged; When frequency does not surpass the bound of current filter transmission band, just still select current wave filter; When frequency just in time drops in the halved belt of two filter transmission bands, will select according to the point of crossing of these two filter transmission bands, when frequency is lower than the point of crossing, just select the wave filter of lower passband, be higher than the wave filter that upper passband is just selected in the point of crossing.
6. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: the fast inadequately and limited problem of memory source for the arithmetic speed that overcomes single-chip microcomputer, adopt assembly language establishment real number FFT program, sequence to the sampling gained is carried out the odd even apportion, strange, even sequence are put into real part and the imaginary part array that FFT calculates respectively, carry out common FFT then and calculate, after calculating is finished, again the gained result is converted to the result of the FFT of actual point; Uniform data uses the Q13 fixed-point number to represent, promptly represent 1 data, most significant digit is-symbol position, the size of 15 remaining bit representation data with 16, wherein, high 2 integral parts that are used for representing in the data, in calculating as safeguard bit, the fraction part in the minimum 13 bit representation data, the data that sampling comes are placed on low 12 earlier, then, move to left 1, to reduce the EMS memory occupation amount; The employing fixed-point number calculates, and its radix point of data that uses in multiplication and additional calculation process is all fixed, to improve computing velocity; In the FFT calculating process, every calculating through the one-level dish factor, its as a result maximum possible can enlarge 3 times, along with the increase of calculating progression, the data of representing with the Q13 form are certain to overflow, so, in computation process, must move to right to data, to prevent overflowing of data, still, in actual computation, be not that every grade of result calculated all can be overflowed, if be shifted to the result this moment, will reduce the FFT precision of calculation results, for this reason, earlier judge that whether this one-level result of calculation is greater than 1, when greater than 1 the time, just displacement just is not shifted less than 1.
7. a kind of battery powered digital vortex street/precession flowmeter as claimed in claim 1, it is characterized in that: the result that the flow rate calculation module is calculated according to pulsed frequency, at first judge the flow rate calculation first time whether system powers on later, general flow rate calculation value for the first time is not too accurate, so, if calculate for the first time, be 0 with regard to the frequency of calculating is set, and deposit this frequency in formation; If not, judge that then whether pulsed frequency is less than the cutoff frequency that is provided with, if it is 0 that frequency just is set, and deposits this frequency in formation; Then judge the frequency calculated whether within the scope of current filter pass band, if, deposit this frequency in formation, if do not exist,, preserve the double just now frequency resultant of calculating just with whole formation zero clearing of depositing frequency; Then judge the whether double frequency jitter scope that exceeds setting of the frequency calculated, if, preserve the double just now frequency resultant of calculating just with whole formation zero clearing of depositing frequency; Then the frequency that is kept in the formation is sorted, find out the number of nonzero frequency, judge then whether the number of nonzero frequency surpasses 5, if, calculate the frequency of vortex street/precession amount signal with regard to the nonzero frequency in the direct average queue; If not, just find out the maximal value in the nonzero frequency in the formation, second largest value, minimum value, sub-minimum is removed these 4 in nonzero frequency values then, and the nonzero frequency of remainder is averaged, and calculates the frequency of vortex flowmeter signals; Then select instrument coefficient, calculate instantaneous delivery; Judge then whether the temperature pressure compensation time arrive,, then the instantaneous delivery that calculates is carried out the temperature and pressure compensation, calculate integrated flow then,, directly calculate integrated flow if do not arrive if arrived.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101122135A CN101782407B (en) | 2010-02-11 | 2010-02-11 | Digital vortex street/precession flowmeter powered by battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101122135A CN101782407B (en) | 2010-02-11 | 2010-02-11 | Digital vortex street/precession flowmeter powered by battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101782407A true CN101782407A (en) | 2010-07-21 |
| CN101782407B CN101782407B (en) | 2011-09-28 |
Family
ID=42522497
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010101122135A Expired - Fee Related CN101782407B (en) | 2010-02-11 | 2010-02-11 | Digital vortex street/precession flowmeter powered by battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101782407B (en) |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102042879A (en) * | 2010-09-21 | 2011-05-04 | 安徽送变电工程公司 | Intelligent data acquisition instrument for measuring temperature of concrete of electric transmission line pole and tower foundation |
| CN103439552A (en) * | 2013-08-19 | 2013-12-11 | 国家电网公司 | Chip capable of recognizing high-frequency and strong-magnetism electricity stealing behavior |
| CN103630171A (en) * | 2013-08-19 | 2014-03-12 | 三正集团股份有限公司 | Mining screw-in vortex flow sensor |
| CN103812088A (en) * | 2012-11-12 | 2014-05-21 | 苏州工业园区新宏博通讯科技有限公司 | Electricity-taking protection device |
| CN104132691A (en) * | 2014-07-31 | 2014-11-05 | 国网上海市电力公司 | Operating parameter acquisition circuit of flow battery charging and discharging system |
| CN104501883A (en) * | 2014-12-19 | 2015-04-08 | 重庆市畜牧科学院 | High-precision animal drinking record system |
| CN104572076A (en) * | 2014-12-12 | 2015-04-29 | 烟台智慧云谷云计算有限公司 | Soft filter algorithm for analog acquisition and filter system |
| CN105181032A (en) * | 2015-08-17 | 2015-12-23 | 合肥工业大学 | High temperature resistance digital two-wire system HART intelligent vortex flowmeter |
| CN105337265A (en) * | 2014-06-30 | 2016-02-17 | 南京德朔实业有限公司 | Discharge protection circuit and control method thereof |
| CN107525551A (en) * | 2017-09-26 | 2017-12-29 | 威海坤科流量仪表股份有限公司 | Vortex-shedding meter |
| CN109075303A (en) * | 2016-05-13 | 2018-12-21 | 杜克斯有限公司 | battery |
| CN109341784A (en) * | 2018-11-16 | 2019-02-15 | 安徽金大仪器有限公司 | A kind of low-power consumption turbine flowmeter |
| CN111158419A (en) * | 2020-01-13 | 2020-05-15 | 维沃移动通信有限公司 | Power supply circuit, current acquisition method and electronic equipment |
| CN111272252A (en) * | 2020-03-09 | 2020-06-12 | 苏州长光华医生物医学工程有限公司 | Automatic calibration method, system and device for detecting liquid amount of substrate liquid |
| CN112033491A (en) * | 2020-08-19 | 2020-12-04 | 重庆市山城燃气设备有限公司 | Sensor combination for natural gas meter |
| CN112230212A (en) * | 2020-09-28 | 2021-01-15 | 北京环境特性研究所 | Radar ranging signal processing method and device |
| CN112540558A (en) * | 2020-11-09 | 2021-03-23 | 蚌埠依爱消防电子有限责任公司 | Implementation method for reducing power consumption of two-wire product |
| CN112629599A (en) * | 2020-12-24 | 2021-04-09 | 中国航天空气动力技术研究院 | Circuit of precession vortex flowmeter and precession vortex flowmeter |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3995482A (en) * | 1973-03-30 | 1976-12-07 | Chrysler Corporation | Vortex swirl flowmeter sensor circuit |
| US6170338B1 (en) * | 1997-03-27 | 2001-01-09 | Rosemont Inc. | Vortex flowmeter with signal processing |
| CN101162162A (en) * | 2007-11-14 | 2008-04-16 | 合肥工业大学 | Low-power consumption two-wire system vortex flowmeter |
| CN101451864A (en) * | 2008-12-22 | 2009-06-10 | 合肥工业大学 | Improved low power consumption two-wire system vortex shedding flowmeter |
| CN101614566A (en) * | 2009-06-29 | 2009-12-30 | 合肥工业大学 | Low-power and two-wire vortex shedding flowmeter based on Fast Fourier Transform (FFT) |
-
2010
- 2010-02-11 CN CN2010101122135A patent/CN101782407B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3995482A (en) * | 1973-03-30 | 1976-12-07 | Chrysler Corporation | Vortex swirl flowmeter sensor circuit |
| US6170338B1 (en) * | 1997-03-27 | 2001-01-09 | Rosemont Inc. | Vortex flowmeter with signal processing |
| CN101162162A (en) * | 2007-11-14 | 2008-04-16 | 合肥工业大学 | Low-power consumption two-wire system vortex flowmeter |
| CN101451864A (en) * | 2008-12-22 | 2009-06-10 | 合肥工业大学 | Improved low power consumption two-wire system vortex shedding flowmeter |
| CN101614566A (en) * | 2009-06-29 | 2009-12-30 | 合肥工业大学 | Low-power and two-wire vortex shedding flowmeter based on Fast Fourier Transform (FFT) |
Cited By (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102042879A (en) * | 2010-09-21 | 2011-05-04 | 安徽送变电工程公司 | Intelligent data acquisition instrument for measuring temperature of concrete of electric transmission line pole and tower foundation |
| CN103812088A (en) * | 2012-11-12 | 2014-05-21 | 苏州工业园区新宏博通讯科技有限公司 | Electricity-taking protection device |
| CN103439552A (en) * | 2013-08-19 | 2013-12-11 | 国家电网公司 | Chip capable of recognizing high-frequency and strong-magnetism electricity stealing behavior |
| CN103630171A (en) * | 2013-08-19 | 2014-03-12 | 三正集团股份有限公司 | Mining screw-in vortex flow sensor |
| CN105337265B (en) * | 2014-06-30 | 2018-10-02 | 南京德朔实业有限公司 | Discharge protection circuit and control method thereof |
| CN105337265A (en) * | 2014-06-30 | 2016-02-17 | 南京德朔实业有限公司 | Discharge protection circuit and control method thereof |
| CN104132691A (en) * | 2014-07-31 | 2014-11-05 | 国网上海市电力公司 | Operating parameter acquisition circuit of flow battery charging and discharging system |
| CN104132691B (en) * | 2014-07-31 | 2017-06-16 | 国网上海市电力公司 | A kind of operational factor Acquisition Circuit of flow battery charge and discharge system |
| CN104572076A (en) * | 2014-12-12 | 2015-04-29 | 烟台智慧云谷云计算有限公司 | Soft filter algorithm for analog acquisition and filter system |
| CN104572076B (en) * | 2014-12-12 | 2018-04-17 | 烟台智慧云谷云计算有限公司 | The soft filtering algorithm and filtering system of a kind of analog acquisition |
| CN104501883A (en) * | 2014-12-19 | 2015-04-08 | 重庆市畜牧科学院 | High-precision animal drinking record system |
| CN104501883B (en) * | 2014-12-19 | 2018-07-13 | 重庆市畜牧科学院 | Animal high-precision drinking-water record system |
| CN105181032B (en) * | 2015-08-17 | 2018-07-13 | 合肥工业大学 | The digital two-wire system HART intelligent vortex shedding flowmeters of high temperature resistance |
| CN105181032A (en) * | 2015-08-17 | 2015-12-23 | 合肥工业大学 | High temperature resistance digital two-wire system HART intelligent vortex flowmeter |
| US10950843B2 (en) | 2016-05-13 | 2021-03-16 | Dukosi Limited | Electric batteries |
| CN109075303A (en) * | 2016-05-13 | 2018-12-21 | 杜克斯有限公司 | battery |
| US11575185B2 (en) | 2016-05-13 | 2023-02-07 | Dukosi Limited | Electric batteries |
| CN107525551A (en) * | 2017-09-26 | 2017-12-29 | 威海坤科流量仪表股份有限公司 | Vortex-shedding meter |
| CN109341784A (en) * | 2018-11-16 | 2019-02-15 | 安徽金大仪器有限公司 | A kind of low-power consumption turbine flowmeter |
| CN111158419A (en) * | 2020-01-13 | 2020-05-15 | 维沃移动通信有限公司 | Power supply circuit, current acquisition method and electronic equipment |
| CN111272252A (en) * | 2020-03-09 | 2020-06-12 | 苏州长光华医生物医学工程有限公司 | Automatic calibration method, system and device for detecting liquid amount of substrate liquid |
| CN112033491A (en) * | 2020-08-19 | 2020-12-04 | 重庆市山城燃气设备有限公司 | Sensor combination for natural gas meter |
| CN112230212A (en) * | 2020-09-28 | 2021-01-15 | 北京环境特性研究所 | Radar ranging signal processing method and device |
| CN112230212B (en) * | 2020-09-28 | 2023-06-16 | 北京环境特性研究所 | Radar ranging signal processing method and device |
| CN112540558A (en) * | 2020-11-09 | 2021-03-23 | 蚌埠依爱消防电子有限责任公司 | Implementation method for reducing power consumption of two-wire product |
| CN112629599A (en) * | 2020-12-24 | 2021-04-09 | 中国航天空气动力技术研究院 | Circuit of precession vortex flowmeter and precession vortex flowmeter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101782407B (en) | 2011-09-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101782407B (en) | Digital vortex street/precession flowmeter powered by battery | |
| CN101451864B (en) | Improved low power consumption two-wire system vortex shedding flowmeter | |
| CN100470207C (en) | Low-power consumption two-wire system vortex flowmeter | |
| CN100453985C (en) | Portable two-channel vibrating functional failure diagnostic apparatus | |
| CN100469031C (en) | Intelligent radio sensing network node for engineering structure health monitoring | |
| CN102445661A (en) | Reconfigurable dual-channel aero-generator in situ fault diagnosis instrument based on acoustic emission and vibration features | |
| CN100385207C (en) | Low cost intelligent vortex shedding flowmeter signal processing system based on DSP | |
| CN104914304A (en) | Electric energy accurate measurement method and electric energy accurate measurement device under fluctuating load | |
| CN101706299A (en) | Coriolis mass flow transmitter based on DSP | |
| CN103365965B (en) | A kind of aggregation process method and apparatus of data | |
| CN102322904B (en) | Vortex shedding flow meter based on self-adaptive fast Fourier transformation | |
| CN106504504A (en) | The data integrated harvester of water, electricity, gas table | |
| CN2930062Y (en) | Electric energy quality online analysis monitor | |
| CN200993665Y (en) | Small digitalized prase-comparing measuring device | |
| CN204881604U (en) | Distributing type bridge does not have line strain collection system based on WIFI | |
| CN201464006U (en) | Novel electronic belt weigher controller | |
| CN202075342U (en) | Three-phase SOC (system-on-chip) intelligent power meter | |
| CN204679550U (en) | Electric energy accurate measuring device under a kind of fluctuating load | |
| CN204543124U (en) | A kind of intelligent remote infusion information measuring instrument and monitoring system thereof | |
| CN202158875U (en) | Vortex flow meter | |
| CN106370186A (en) | Rapid low-power-consumption fusion system and method for sensor | |
| CN201094096Y (en) | Hydraulic turbine swing embedded type surveillance protecting equipment | |
| CN203259272U (en) | Calorimeter with sound velocity real-time calibration function | |
| CN202305666U (en) | Direct current electric energy meter | |
| CN205261238U (en) | Gas pipe network leaks transient pressure ripples detection and analysis system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110928 Termination date: 20180211 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |