CN114459576A - Signal diagnosis device applied to ultrasonic water meter and control method thereof - Google Patents
Signal diagnosis device applied to ultrasonic water meter and control method thereof Download PDFInfo
- Publication number
- CN114459576A CN114459576A CN202210168816.XA CN202210168816A CN114459576A CN 114459576 A CN114459576 A CN 114459576A CN 202210168816 A CN202210168816 A CN 202210168816A CN 114459576 A CN114459576 A CN 114459576A
- Authority
- CN
- China
- Prior art keywords
- transducer
- signal
- downstream
- ultrasonic
- time
- 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 discloses a signal diagnosis device applied to an ultrasonic water meter and a control method thereof. The problems that in the prior art, more extra hardware circuits are adopted, the power consumption is high, and the ultrasonic water meter is not suitable for application are solved; the invention comprises the following steps: the upstream transducer transmits an upstream ultrasonic signal or receives a downstream ultrasonic signal reflected by the auxiliary transducer; the downstream transducer transmits a downstream ultrasonic signal or receives an upstream ultrasonic signal reflected by the auxiliary transducer; the auxiliary transducer reflects the ultrasonic signal sent by the upstream transducer or the downstream transducer; the signal processing circuit controls the upstream transducer and the downstream transducer to transmit or receive ultrasonic signals, respectively obtains the time for the auxiliary transducer and the upstream/downstream transducer to receive the ultrasonic signals, diagnoses whether the received ultrasonic signals have wrong waves and corrects the wrong waves. The characteristic that the mechanical structure is fixed and the sound wave transmission in a uniform medium is stable is utilized only through adding one auxiliary transducer, whether wrong waves exist in the received signals or not is diagnosed and corrected, the structure is simple, and the cost is low.
Description
Technical Field
The invention relates to the field of ultrasonic signal diagnosis, in particular to a signal diagnosis device applied to an ultrasonic water meter and a control method thereof.
Background
In the application of water flow measurement, an ultrasonic water meter is used as a new intelligent flow meter to replace a mechanical water meter, the working principle of the ultrasonic water meter is a time difference method, and the instantaneous flow and the accumulated flow of water are further calculated by analyzing and calculating the flow speed by detecting the time difference generated when ultrasonic waves propagate in water in a forward flow and a reverse flow. Compared with mechanical water meter, it has the features of high accuracy, low initial flow, no pressure loss, wide range ratio, long service life, no movable parts, etc.
In order to realize the specific problem of measuring the flow rate by the time difference method, a conventional solution is to adopt a threshold comparison method, that is, a fixed voltage is used as a threshold to detect whether a received ultrasonic signal arrives, and if a signal with a corresponding amplitude is detected, the comparison is switched to zero-crossing comparison to perform conversion calculation of accurate time.
To implement this measurement method, a common sensor structure is a direct-type sensor.When a medium flows in the pipeline, the ultrasonic transducer at the upstream end transmits an ultrasonic signal, the ultrasonic signal is transmitted along the downstream direction through the medium, and the signal transmission time received by the transducer at the downstream end is recorded as T+On the contrary, the time of the ultrasonic signal emitted from the downstream end and propagating in the upstream transducer in the reverse flow is recorded as T-And recording the difference between the upstream propagation time and the downstream propagation time as DeltaT, and if the difference is measured, calculating the average velocity V of the fluid in the outlet pipe according to the following relation:
△T＝(T--T+)
in the formula:
m is the linear propagation frequency of the sound wave in the fluid between the two probes, and the M is 1;
d is the inner diameter of the pipeline;
theta is the angle between the sound beam and the fluid flow direction.
In the traditional ultrasonic threshold level method, the first wave crest exceeding the threshold is used as the head wave, and the time of a certain zero crossing point after the head wave is measured is used as the propagation time of a signal, so that the anti-interference capability is poor, when the amplitude of the signal changes greatly or is in a critical value, the head wave identification is wrong, the measured zero crossing points are different, the measured delta T deviation is 1 or more signal cycle times, the measurement accuracy is seriously influenced, and the problem of 'wrong wave' is solved.
The wrong wave problem has a great influence on the measurement accuracy, and researchers propose methods such as high-speed AD sampling cross-correlation, envelope analysis and the like to avoid the wrong wave, but the methods mostly need high-speed AD conversion or more extra hardware circuits for supporting, and the power consumption is high, so that the methods are not suitable for the application of the ultrasonic water meter. For example, a chinese patent document discloses "a false wave prevention signal processing circuit of a gas ultrasonic flow meter", which has publication No. CN109612541B, and includes an ultrasonic receiving transducer for receiving an ultrasonic signal; the controllable gain amplifying circuit is connected with the ultrasonic receiving transducer; the analog-to-digital conversion circuit is connected with the controllable gain amplification circuit; the dual-threshold detection circuit is connected with the controllable gain amplification circuit; the peak value holding circuit is connected with the controllable gain amplifying circuit; the program-controlled multi-threshold comparison circuit is connected with the peak holding circuit; the wave selection circuit is respectively connected with the double-threshold detection circuit and the program-controlled multi-threshold comparison circuit; and the timing circuit is connected with the wave selection circuit. This scheme adopts more extra hardware circuit, and the consumption is high, is not suitable for the application of supersound water gauge.
Disclosure of Invention
The invention mainly solves the problems that the prior art adopts more extra hardware circuits, has high power consumption and is not suitable for the application of the ultrasonic water meter; the signal diagnosis device is applied to an ultrasonic water meter and a control method thereof, and solves the problem of wave error by controlling a detection path, gain control and time signal processing of an ultrasonic receiving signal.
The technical problem of the invention is mainly solved by the following technical scheme:
a signal diagnosis apparatus applied to an ultrasonic water meter, comprising:
the upstream transducer transmits an upstream ultrasonic signal or receives a downstream ultrasonic signal reflected by the auxiliary transducer;
the downstream transducer transmits a downstream ultrasonic signal or receives an upstream ultrasonic signal reflected by the auxiliary transducer;
the auxiliary transducer reflects the ultrasonic signal sent by the upstream transducer or the downstream transducer;
and the signal processing circuit controls the upstream transducer and the downstream transducer to transmit or receive ultrasonic signals, respectively acquires the time for the auxiliary transducer and the upstream/downstream transducers to receive the ultrasonic signals, diagnoses whether the received ultrasonic signals have wrong waves and corrects the wrong waves.
According to the scheme, the auxiliary transducer is added on the ultrasonic transmission path, signals are reflected between the upstream transducer and the downstream transducer to be transmitted, two sections of transmission time are obtained in one measurement, the relation between the two sections of transmission time and the total transmission time are compared, the signal receiving and transmitting conditions of the measurement are diagnosed, whether a wrong wave phenomenon exists or not is judged, and error correction is carried out timely.
According to the scheme, the hardware is simple by adding the auxiliary transducer; by utilizing the characteristics of mechanical structure fixation and stable sound wave transmission in a uniform medium, whether the received signal has wrong waves or not can be diagnosed and corrected. The battery power of the ultrasonic water meter is mainly consumed in signal transmission and time measurement, and the system does not increase redundant signal transmission times and is close to the power consumption of a common system. Because the caliber of the water meter is generally smaller than DN300, the V-method structure has the measuring effect of approximate double track while the signal intensity is satisfied. When one of the upstream and downstream transducers has signal failure, the signal transmitting and receiving capability can be lost, and the receiving signal of the auxiliary transducer can be used for judging which transducer has the transmitting and receiving problem.
Preferably, the signal processing circuit includes:
the main control module is configured with a time receiving window of the time-to-digital conversion module, controls the switching channel of the multi-channel analog switch, and judges whether the received ultrasonic signals have wrong waves or not and corrects the wrong waves;
the multi-channel analog switch switches channels among the upstream transducer, the downstream transducer, the auxiliary transducer, the signal ground, the ultrasonic signal transmitting module and the signal amplifying and filtering module;
the time-to-digital conversion module is used for setting a signal trigger level threshold value and the time for receiving a signal;
the signal amplifying and filtering module amplifies and filters the ultrasonic signals received by the auxiliary transducer or the upstream/downstream transducers;
the ultrasonic signal transmitting module is communicated with the upstream transducer or the downstream transducer through the multi-path analog switch to transmit an ultrasonic signal;
and the signal amplitude sampling module is used for acquiring the signal amplitude after the ultrasonic signal amplification and filtration and sending the signal amplitude to the main control module.
In the scheme, the connection between each transducer and other modules is switched by a multi-path analog switch, so that the transmission and the reception of ultrasonic signals are realized, and two sections of time of downstream transmission and two sections of time of countercurrent transmission are respectively recorded; by using the relationship between the two transmission times and the comparison with the total transmission time, the signal receiving and transmitting conditions of the measurement can be diagnosed, whether the wave error phenomenon exists or not can be diagnosed, and the error can be corrected in time.
Preferably, the upstream transducer and the downstream transducer are arranged on the same side in the water meter pipe, and the auxiliary transducer is arranged at the intersection point of the perpendicular bisector of the upstream transducer and the downstream transducer and the other side in the water meter pipe.
Because the caliber of the water meter is generally smaller than DN300, the V-method structure has the measuring effect of approximate double track while the signal intensity is satisfied.
A control method of a signal diagnosis device applied to an ultrasonic water meter comprises the following steps:
s1: calibrating the ratio K of the two sections of transmission distances in the process of downstream transmission or countercurrent transmission, and calculating the deviation percentage K of unit error waves;
s2: measuring downstream transmission time, and sequentially recording ultrasonic transmission time from an upstream transducer to an auxiliary transducer and from the auxiliary transducer to a downstream transducer through a signal processing circuit;
s3: measuring the countercurrent transmission time, and sequentially recording the ultrasonic transmission time from the downstream transducer to the auxiliary transducer and from the auxiliary transducer to the upstream transducer through a signal processing circuit;
s4: and calculating deviation according to the ultrasonic transmission time obtained by measuring the downstream transmission time and the upstream transmission time and the transmission distance ratio K, comparing the deviation with the deviation percentage K of the fault wave to judge whether the fault wave phenomenon exists or not, and adjusting a trigger level threshold.
The auxiliary transducer is added on the ultrasonic transmission path, signals are reflected between the upstream transducer and the downstream transducer to be transmitted, two sections of transmission time can be obtained in one measurement, the relation between the two sections of transmission time and the total transmission time are compared, the signal receiving and transmitting conditions of the measurement can be diagnosed, whether a wrong wave phenomenon exists or not can be diagnosed, and error correction can be carried out in time.
Preferably, the step S1 specifically includes the following steps:
s101: the calibration is carried out under the condition of full pipe, and the ratio K of the transmission distances at two ends, which is obtained by calculation under the condition of no error wave, is as follows:
wherein, ta1An ultrasonic first downstream transit time from the upstream transducer to the auxiliary transducer;
ta2a second downstream transit time for the ultrasound from the auxiliary transducer to the downstream transducer;
tb1a first upstream transit time for the ultrasound from the auxiliary transducer to the upstream transducer;
tb2a second upstream transit time of ultrasound from the downstream transducer to the auxiliary transducer;
s102: calculating the deviation percentage k of one wave by one wave of the current water meter according to the caliber of the water pipe;
wherein t is the duration of transmission of one wave;
d is the diameter of the water pipe;
c is the speed of sound in water;
theta is an included angle between an ultrasonic path from the upstream transducer to the auxiliary transducer and the pipe wall of the water pipe;
s103: the multi-channel analog switch connects the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to signal ground.
The data is calculated and used as standard data for judging whether error waves exist later.
Preferably, the step S2 specifically includes the following steps:
s201: the multi-channel analog switch connects the channel where the upstream transducer is located with the ultrasonic signal transmitting module, the main control module configures a time receiving window of the time-to-digital conversion module as the time for the auxiliary transducer to receive signals, and sets a trigger level threshold as a level Ua1；
S202: transmitting an ultrasonic signal and starting the timing; the multi-path analog switch switches the channel where the auxiliary transducer is located to a signal amplification filtering module;
s203: the auxiliary transducer receives the signal, and the time-to-digital conversion module obtains the ultrasonic first downstream transmission time t after the signal is processed by the signal amplification and filtering modulea1(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a first downstream signala1；
S204: the multi-channel analog switch switches the auxiliary transducer channel switch to a signal ground, and the downstream transducer channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window as the time for the downstream transducer to receive signals, and the trigger level threshold is level Ua2；
S205: the downstream transducer receives the signal, and the time-to-digital conversion module obtains the ultrasonic second downstream transmission time t after the signal is processed by the signal amplification and filtering modulea2(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a second downstream signala2；
S206: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete downstream transmission time measurement.
Through a multi-path analog switch, the transducer is sequentially conducted with different modules for transmitting and receiving signals, so that the time of two sections of paths of downstream transmission is obtained for calculating whether wave error occurs or not.
Preferably, the step S3 specifically includes the following steps:
s301: the multi-channel analog switch connects the channel where the downstream transducer is located with the ultrasonic signal transmitting module, the main control module configures a time receiving window of the time-to-digital conversion module as the time for the auxiliary transducer to receive signals, and sets a trigger level threshold as a level Ub1；
S302: transmitting an ultrasonic signal and starting the timing; the multi-path analog switch switches the channel where the auxiliary transducer is located to the signal amplification and filtering module;
s303: the auxiliary transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and then the time-to-digital conversion module obtains the ultrasonic first countercurrent transmission time tb1(ii) a Meanwhile, the signal amplitude sampling module obtains a first counter signalNumber intensity Qb1；
S304: the multi-channel analog switch switches the auxiliary transducer channel switch to a signal ground, and the upstream transducer channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window as the time when the upstream transducer receives the signal, and the trigger level threshold is level Ub2；
S305: the upstream transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and then the time-to-digital conversion module obtains the ultrasonic second countercurrent transmission time tb2(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a second countercurrent signalb2；
S306: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete the measurement of the upstream transmission time.
Through a multi-path analog switch, the transducer is sequentially conducted to different modules for transmitting and receiving signals, so that the time of two sections of paths of countercurrent transmission is obtained for calculating whether waves are wrong or not.
Preferably, the step S4 specifically includes the following steps:
s401: calculating the deviation k of downstream transmission1；
S402: comparing the deviations k1Determining the deviation percentage k from unit error wave, determining the number of error waves transmitted downstream, and sequentially adjusting the level Ua2Sum level Ua1；
S403: let Ub2＝Ua2Calculating the deviation k of the upstream transmission2；
S404: comparison of the deviations k2Deviation percentage k from unit error wave, adjusting level Ub1Let k be2Approximately equal to k.
And diagnosing whether the wave error phenomenon exists or not and correcting the error in time according to the relation between the two sections of transmission time and the total transmission time by comparing the two sections of transmission time with the total transmission time.
The invention has the beneficial effects that:
1. the characteristic that the mechanical structure is fixed and the sound wave transmission in a uniform medium is stable is utilized only through adding one auxiliary transducer, whether wrong waves exist in the received signals or not is diagnosed and corrected, the structure is simple, and the cost is low.
2. The unnecessary signal emission times are not increased, the power consumption is similar to that of a common system, and the energy consumption is low.
And 3. the V-method structure has the approximate two-channel measurement effect while the signal intensity is satisfied.
4. When one of the upstream and downstream transducers has signal failure, the receiving signal of the auxiliary transducer is used to judge which transducer has the problem of transmitting and receiving.
Drawings
Fig. 1 is a block diagram of a schematic circuit connection structure of the signal diagnosis device of the present invention.
FIG. 2 is a schematic view of the transducer mounting location of the present invention.
In the figure, 1, an upstream transducer, 2, a downstream transducer, 3, an auxiliary transducer, 4, a signal processing circuit, 41, a main control module, 42, a multi-path analog switch, 43, a time-to-digital conversion module, 44, a signal amplification and filtering module, 45, an ultrasonic signal transmitting module, 46 and a signal amplitude sampling module are arranged.
Detailed Description
The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.
Example (b):
in the signal diagnosis device applied to the ultrasonic water meter and the control method thereof of the embodiment, as shown in fig. 2, the device comprises an upstream transducer 1, a downstream transducer 2 and an auxiliary transducer 3.
The upstream transducer 1 and the downstream transducer 2 are arranged on the same side of the water meter pipe, and the auxiliary transducer 3 is arranged on the other side of the water meter pipe. The auxiliary transducer 3 is disposed on the midperpendicular of the upstream transducer 1 and the downstream transducer 2.
Because the caliber of the water meter is generally smaller than DN300, the V-method structure has the measuring effect of approximate double track while the signal intensity is satisfied.
As shown in fig. 1, the apparatus further comprises a signal processing circuit 4. The signal processing circuit 4 specifically includes a main control module 41, a multi-channel analog switch 42, a time-to-digital conversion module 43, a signal amplification and filtering module 44, an ultrasonic signal transmitting module 45, and a signal amplitude sampling module.
The upstream transducer 1, the downstream transducer 2 and the auxiliary transducer 3 are respectively connected with channels of a multi-channel analog switch 42, and the multi-channel analog switch 42 is also respectively connected with an output end of an ultrasonic signal transmitting module 45 and an input end of a signal amplifying and filtering module 44. The control terminal of the multi-path analog switch 42 is connected with the control output terminal of the main control module 41.
The multi-channel analog switch 42 is controlled by the main control module 41 to switch the channels between the upstream transducer 1, the downstream transducer 2 and the auxiliary transducer 3 and the signal ground, the ultrasonic signal transmitting module 45 and the signal amplifying and filtering module 44.
The output end of the ultrasonic signal transmitting module 45 is connected with the multi-path analog switch 42, the control end of the ultrasonic signal transmitting module 45 is connected with the time-to-digital conversion module 43, and the ultrasonic signal transmitting module 45 is conducted with the upstream transducer 1 or the downstream transducer 2 through the multi-path analog switch 42 to transmit ultrasonic signals.
The signal amplitude sampling module 46 collects the signal amplitude after the ultrasonic signal amplification and filtering, and sends the signal amplitude to the main control module 41.
The signal amplifying and filtering module 44 amplifies and filters the ultrasonic signals received by the auxiliary transducer 3 or the upstream/downstream transducers.
The time-to-digital conversion module 41 is a TDC module with adjustable threshold, and the time-to-digital conversion module 41 adjusts the threshold and measures the time window parameter through a single chip microcomputer control.
The main control module 41 is configured to configure a time receiving window of the time-to-digital conversion module 43, control the multi-channel analog switch 42 to switch channels, and disconnect whether the received ultrasonic signals have wrong waves and correct the wrong waves. In this embodiment, the main control module 41 is a single chip.
The auxiliary transducer is added on the ultrasonic transmission path, the signal is reflected and transmitted between the upstream transducer and the downstream transducer, two sections of transmission time are obtained in one measurement, the relationship between the two sections of transmission time and the total transmission time are compared, the signal receiving and transmitting conditions of the current measurement are diagnosed, whether a wrong wave phenomenon exists or not is judged, and error correction is carried out in time.
The control method of the signal diagnosis device applied to the ultrasonic water meter comprises the following steps:
s1: and calibrating the ratio K of the two sections of transmission distances in the forward flow transmission or reverse flow transmission process, and calculating the deviation percentage K of the unit error wave.
S101: the calibration is carried out under the condition of full pipe, and the ratio K of the transmission distances at two ends, which is obtained by calculation under the condition of no error wave, is as follows:
wherein, ta1An ultrasonic first downstream transit time from the upstream transducer to the auxiliary transducer;
ta2a second downstream transit time for the ultrasound from the auxiliary transducer to the downstream transducer;
tb1a first upstream transit time for the ultrasound from the auxiliary transducer to the upstream transducer;
tb2the ultrasonic second upstream transit time from the downstream transducer to the auxiliary transducer.
Due to production inconsistency, the specific algorithm is implemented by first performing a ratio K of two transmission distances of the factory calibration signal.
S102: calculating the deviation percentage k of one wave by one wave of the current water meter according to the caliber of the water pipe;
wherein t is the duration of transmission of one wave;
d is the diameter of the water pipe;
c is the speed of sound in water;
theta is the included angle between the ultrasonic path from the upstream transducer to the auxiliary transducer and the wall of the water pipe.
ta1Unit of (d) is us; for example, if the current water meter misses 1 wave (1MHz), the time duration t for transmitting one wave is 1 us.
S103: the multi-channel analog switch connects the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to signal ground.
S2: downstream transit time measurement, the ultrasonic transit time from the upstream transducer to the auxiliary transducer and from the auxiliary transducer to the downstream transducer are recorded in sequence by the signal processing circuitry.
S201: the multi-path analog switch connects the channel where the upstream transducer is located with the ultrasonic signal transmitting module;
the main control module sends an instruction to the time-to-digital conversion module, a time receiving window (the receiving time window is calculated by the mechanical size and the propagation speed of sound waves in a medium) of the time-to-digital conversion module is configured as the time for the auxiliary transducer to receive signals, and a trigger level threshold is set to be a level Ua1(e.g., 400 mV).
S202: the time digital conversion module controls the ultrasonic signal transmitting module to transmit the ultrasonic signal and starts the timing. And after short time delay, the multi-channel analog switch immediately switches the channel where the auxiliary transducer is located to the signal amplification and filtering module by the main control module.
S203: the auxiliary transducer receives the signal, and the time-to-digital conversion module obtains the ultrasonic first downstream transmission time t after the signal is processed by the signal amplification and filtering modulea1(ii) a At the same time, the time-to-digital conversion module interrupts to inform the main control module of starting signal intensity sampling, and the signal amplitude value sampling module obtains the first downstream signal intensity Qa1。
S204: the multi-channel analog switch switches the auxiliary transducer channel switch to a signal ground, and the downstream transducer channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window for the downstream transducer to be connectedTime of receiving signal, trigger level threshold value is level Ua2。
Due to signal attenuation, level Ua2Need to be lower than the level Ua1Depending on the transducer characteristics, e.g. 300 mV.
S205: the downstream transducer receives the signal, and the time-to-digital conversion module obtains the ultrasonic second downstream transmission time t after the signal is processed by the signal amplification and filtering modulea2(ii) a At the same time, the time-to-digital conversion module interrupts to inform the main control module of starting signal intensity sampling, and the signal amplitude value sampling module obtains the second downstream signal intensity Qa2。
S206: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete downstream transmission time measurement.
S3: and measuring the upstream transmission time, and sequentially recording the ultrasonic transmission time from the downstream transducer to the auxiliary transducer and from the auxiliary transducer to the upstream transducer through a signal processing circuit.
S301: the multi-path analog switch connects the channel where the downstream transducer is located with the ultrasonic signal transmitting module;
the main control module configures a time receiving window of the time-to-digital conversion module as the time for the auxiliary transducer to receive signals, and sets a trigger level threshold value as a level Ub1。
S302: transmitting an ultrasonic signal and starting the timing; and the multi-path analog switch switches the channel where the auxiliary transducer is located to the signal amplification and filtering module.
S303: the auxiliary transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and then the time-to-digital conversion module obtains the ultrasonic first countercurrent transmission time tb1(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a first countercurrent signalb1。
S304: the multi-channel analog switch switches the auxiliary transducer channel switch to a signal ground, and the upstream transducer channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window as the time when the upstream transducer receives the signal, and the trigger level threshold is level Ub2。
S305: the upstream transducer receives the signal viaThe time-to-digital conversion module obtains the second ultrasonic countercurrent transmission time t after the signal amplification and filtering module processesb2(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a second countercurrent signalb2。
S306: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete the measurement of the upstream transmission time.
S4: and calculating deviation according to the ultrasonic transmission time obtained by measuring the downstream transmission time and the upstream transmission time and the transmission distance ratio K, comparing the deviation with the deviation percentage K of the fault wave to judge whether the fault wave phenomenon exists or not, and adjusting a trigger level threshold.
S401: calculating the deviation k of downstream transmission1；
S402: comparison of the deviations k1Determining the deviation percentage k from unit error wave, determining the number of error waves transmitted downstream, and sequentially adjusting the level Ua2Sum level Ua1。
If k is1Approaching k, then t is illustrateda2Missing 1 wave, if k1A multiple of k, then t is stateda2Neglecting to record multiple waves, measuring the next time to lower the threshold level Ua2Experience k in the course of the adjustment1Approximately equal to 0 (no spurious), to k1Approximately equal to-k (1 wave, more), Ua2Taking the intermediate value of the threshold value when no error occurs and the threshold value when 1 wave is recorded more, and keeping Ua2Unchanging, adjusting Ua1To ta1The timing has no intermediate value between the error wave threshold and the 1-wave-recording-time-added threshold.
S403: let Ub2＝Ua2At this time, U is symmetrical due to the forward and reverse flowb2The same wave can be stably triggered; calculating the deviation k of the upstream transmission2；
S404: comparing the deviationsk2Deviation percentage k from unit error wave, adjusting level Ub1Let k be2Approximately equal to k.
So far, the threshold level is basically adjusted, the threshold value does not need to be adjusted in real time in the subsequent flow measurement process, and the formula is compared
If it appears during the measurement
When the signal strength is stable, the reference threshold level of a certain section of time can be flexibly selected according to the fluctuation condition of the receiving time, and then the rest thresholds are calibrated one by one.
According to the scheme, the auxiliary transducer is added on the ultrasonic transmission path, signals are reflected and transmitted between the upstream transducer and the downstream transducer, two sections of transmission time are obtained in one measurement, the relation between the two sections of transmission time and the total transmission time are compared, the signal receiving and transmitting conditions of the measurement are diagnosed, whether a wrong wave phenomenon exists or not is judged, and error correction is carried out timely.
The scheme of the embodiment has simple hardware by adding one auxiliary transducer; by utilizing the characteristics of mechanical structure fixation and stable sound wave transmission in a uniform medium, whether the received signal has wrong waves or not can be diagnosed and corrected.
The battery power of the ultrasonic water meter is mainly consumed in signal transmission and time measurement, and the system does not increase redundant signal transmission times and is close to the power consumption of a common system.
Because the caliber of the water meter is generally smaller than DN300, the V-method structure has the measuring effect of approximate double track while the signal intensity is satisfied. When one of the upstream and downstream transducers has signal failure, the signal transmitting and receiving capability can be lost, and the receiving signal of the auxiliary transducer can be used for judging which transducer has the transmitting and receiving problem.
It should be understood that the examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
Claims (8)
1. A signal diagnosis apparatus applied to an ultrasonic water meter, comprising:
an upstream transducer (1) for transmitting an upstream ultrasonic signal or receiving a downstream ultrasonic signal reflected by the auxiliary transducer (3);
a downstream transducer (2) for transmitting a downstream ultrasonic signal or receiving an upstream ultrasonic signal reflected by the auxiliary transducer (3);
an auxiliary transducer (3) reflecting the ultrasonic signal transmitted by the upstream transducer or the downstream transducer;
and the signal processing circuit (4) controls the upstream transducer and the downstream transducer to transmit or receive ultrasonic signals, respectively acquires the time for the auxiliary transducer and the upstream/downstream transducers to receive the ultrasonic signals, diagnoses whether the received ultrasonic signals have wrong waves and corrects the wrong waves.
2. A signal diagnostic device for an ultrasonic water meter as set forth in claim 1, wherein said signal processing circuit comprises:
the main control module (41) is configured with a time receiving window of the time-to-digital conversion module, controls the switching channel of the multi-channel analog switch, and judges whether the received ultrasonic signals have wrong waves or not and corrects the wrong waves;
the multi-channel analog switch (42) switches channels among the upstream transducer, the downstream transducer, the auxiliary transducer, the signal ground, the ultrasonic signal transmitting module and the signal amplifying and filtering module;
a time-to-digital conversion module (43) for setting a signal trigger level threshold and a time for receiving a signal;
the signal amplification and filtering module (44) amplifies and filters the ultrasonic signals received by the auxiliary transducer or the upstream/downstream transducer;
the ultrasonic signal transmitting module (45) is communicated with the upstream transducer or the downstream transducer through the multi-path analog switch to transmit an ultrasonic signal;
and the signal amplitude sampling module (46) is used for acquiring the signal amplitude after the ultrasonic signal amplification and filtration and sending the signal amplitude to the main control module.
3. A signal diagnostic device as claimed in claim 1, wherein said upstream transducer and said downstream transducer are disposed on the same side of the meter tube, and the auxiliary transducer is disposed at the intersection of the perpendicular bisector of the upstream transducer and the downstream transducer and the opposite side of the meter tube.
4. A control method of a signal diagnosis apparatus applied to an ultrasonic water meter, using the signal diagnosis apparatus applied to an ultrasonic water meter according to claims 1 to 3, characterized by comprising the steps of:
s1: calibrating the ratio K of the two sections of transmission distances in the process of downstream transmission or upstream transmission, and calculating the deviation percentage K of unit error waves;
s2: measuring downstream transmission time, and sequentially recording ultrasonic transmission time from an upstream transducer to an auxiliary transducer and from the auxiliary transducer to a downstream transducer through a signal processing circuit;
s3: measuring the countercurrent transmission time, and sequentially recording the ultrasonic transmission time from the downstream transducer to the auxiliary transducer and from the auxiliary transducer to the upstream transducer through a signal processing circuit;
s4: and calculating deviation according to the ultrasonic transmission time obtained by measuring the downstream transmission time and the upstream transmission time and the transmission distance ratio K, comparing the deviation with the deviation percentage K of the fault wave to judge whether the fault wave phenomenon exists or not, and adjusting a trigger level threshold.
5. The method as claimed in claim 4, wherein the step S1 includes the following steps:
s101: the calibration is carried out under the condition of full pipe, and the ratio K of the transmission distances at two ends, which is obtained by calculation under the condition of no error wave, is as follows:
wherein, ta1An ultrasonic first downstream transit time from the upstream transducer to the auxiliary transducer;
ta2a second downstream transit time for the ultrasound from the auxiliary transducer to the downstream transducer;
tb1a first upstream transit time for the ultrasound from the auxiliary transducer to the upstream transducer;
tb2a second upstream transit time of ultrasound from the downstream transducer to the auxiliary transducer;
s102: calculating the deviation percentage k of one wave by one wave of the current water meter according to the caliber of the water pipe;
wherein t is the duration of transmission of one wave;
d is the diameter of the water pipe;
c is the speed of sound in water;
theta is an included angle between an ultrasonic path from the upstream transducer to the auxiliary transducer and the pipe wall of the water pipe;
s103: the multi-channel analog switch connects the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to signal ground.
6. The method as claimed in claim 4, wherein the step S2 includes the following steps:
s201: the multi-channel analog switch connects the channel where the upstream transducer is located with the ultrasonic signal transmitting moduleThe main control module configures a time receiving window of the time-to-digital conversion module as the time for the auxiliary transducer to receive signals, and sets a trigger level threshold value as a level Ua1；
S202: transmitting an ultrasonic signal and starting the timing; the multi-path analog switch switches the channel where the auxiliary transducer is located to the signal amplification and filtering module;
s203: the auxiliary transducer receives the signal, and the time-to-digital conversion module obtains the ultrasonic first downstream transmission time t after the signal is processed by the signal amplification and filtering modulea1(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a first downstream signala1；
S204: the multi-path analog switch switches the auxiliary energy converter channel switch to a signal ground, and the downstream energy converter channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window as the time for the downstream transducer to receive signals, and the trigger level threshold is level Ua2；
S205: the downstream transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and the time-to-digital conversion module obtains the second ultrasonic downstream transmission time ta2(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a second downstream signala2；
S206: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete downstream transmission time measurement.
7. The method as claimed in claim 4, wherein the step S3 includes the following steps:
s301: the multi-channel analog switch connects the channel where the downstream transducer is located with the ultrasonic signal transmitting module, the main control module configures a time receiving window of the time-to-digital conversion module as the time for the auxiliary transducer to receive signals, and sets a trigger level threshold as a level Ub1；
S302: transmitting an ultrasonic signal and starting the timing; the multi-path analog switch switches the channel where the auxiliary transducer is located to the signal amplification and filtering module;
S303: the auxiliary transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and then the time-to-digital conversion module obtains the ultrasonic first countercurrent transmission time tb1(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a first countercurrent signalb1；
S304: the multi-channel analog switch switches the auxiliary transducer channel switch to a signal ground, and the upstream transducer channel is switched to a signal amplification and filtering module; the time-to-digital conversion module configures a time receiving window as the time when the upstream transducer receives the signal, and the trigger level threshold is level Ub2；
S305: the upstream transducer receives the signal, the signal is processed by the signal amplifying and filtering module, and then the time-to-digital conversion module obtains the ultrasonic second countercurrent transmission time tb2(ii) a Meanwhile, the signal amplitude sampling module obtains the strength Q of a second countercurrent signalb2；
S306: and connecting the channels of the upstream transducer, the downstream transducer and the auxiliary transducer to a signal ground to complete the reverse flow transmission time.
8. The method as claimed in claim 4, wherein the step S4 includes the following steps:
s401: calculating the deviation k of downstream transmission1；
S402: comparison of the deviations k1Determining the deviation percentage k from unit error wave, determining the number of error waves transmitted downstream, and sequentially adjusting the level Ua2Sum level Ua1；
S403: let Ub2＝Ua2Calculating the deviation k of the counter-current transmission2；
S404: comparison of the deviations k2With unit error waveDeviation percentage k, adjustment level Ub1Let k be2Approximately equal to k.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210168816.XA CN114459576B (en) | 2022-02-23 | 2022-02-23 | Control method of signal diagnosis device applied to ultrasonic water meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210168816.XA CN114459576B (en) | 2022-02-23 | 2022-02-23 | Control method of signal diagnosis device applied to ultrasonic water meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114459576A true CN114459576A (en) | 2022-05-10 |
| CN114459576B CN114459576B (en) | 2022-11-29 |
Family
ID=81415583
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210168816.XA Active CN114459576B (en) | 2022-02-23 | 2022-02-23 | Control method of signal diagnosis device applied to ultrasonic water meter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114459576B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115527502A (en) * | 2022-08-04 | 2022-12-27 | 浙江迪元仪表有限公司 | Infrared induction-based intelligent water meter backlight control system and method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10254053A1 (en) * | 2002-11-19 | 2004-06-03 | Endress + Hauser Flowtec Ag, Reinach | Method and device for determining and / or monitoring a volume and / or mass flow |
| US20100095782A1 (en) * | 2007-12-05 | 2010-04-22 | Ferencz Gyoergy | Method and apparatus for determining the flow parameters of a streaming medium |
| CN102589627A (en) * | 2012-02-23 | 2012-07-18 | 北京理工大学 | Absolute propagation time measuring method for ultrasonic flow meter |
| CN104296814A (en) * | 2014-11-10 | 2015-01-21 | 厦门大学 | Flow measuring device for sewage containing solid garbage |
| CN111473827A (en) * | 2020-05-28 | 2020-07-31 | 宁波大学 | V-shaped sound channel zero drift elimination method |
| CN113917184A (en) * | 2021-09-03 | 2022-01-11 | 新开普电子股份有限公司 | Ultrasonic speed measurement method and device |
-
2022
- 2022-02-23 CN CN202210168816.XA patent/CN114459576B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10254053A1 (en) * | 2002-11-19 | 2004-06-03 | Endress + Hauser Flowtec Ag, Reinach | Method and device for determining and / or monitoring a volume and / or mass flow |
| US20100095782A1 (en) * | 2007-12-05 | 2010-04-22 | Ferencz Gyoergy | Method and apparatus for determining the flow parameters of a streaming medium |
| CN102589627A (en) * | 2012-02-23 | 2012-07-18 | 北京理工大学 | Absolute propagation time measuring method for ultrasonic flow meter |
| CN104296814A (en) * | 2014-11-10 | 2015-01-21 | 厦门大学 | Flow measuring device for sewage containing solid garbage |
| CN111473827A (en) * | 2020-05-28 | 2020-07-31 | 宁波大学 | V-shaped sound channel zero drift elimination method |
| CN113917184A (en) * | 2021-09-03 | 2022-01-11 | 新开普电子股份有限公司 | Ultrasonic speed measurement method and device |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115527502A (en) * | 2022-08-04 | 2022-12-27 | 浙江迪元仪表有限公司 | Infrared induction-based intelligent water meter backlight control system and method |
| CN115527502B (en) * | 2022-08-04 | 2024-04-05 | 浙江迪元仪表有限公司 | Intelligent water meter backlight control system and method based on infrared induction |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114459576B (en) | 2022-11-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112304375B (en) | Ultrasonic flow sensor and flow measurement method thereof | |
| CN109579950B (en) | Mistake proofing ripples detection device of gaseous ultrasonic flowmeter | |
| CA2557432A1 (en) | Ultrasonic flowmeter and ultrasonic flow rate measurement method | |
| CN114459576B (en) | Control method of signal diagnosis device applied to ultrasonic water meter | |
| CN105181046A (en) | Digitalized ultrasonic flowmeter system based on dual-core architecture and method thereof | |
| JP2007187506A (en) | Ultrasonic flowmeter | |
| CN112649056A (en) | Ultrasonic gas flow measuring method and device | |
| CN113558659A (en) | High-precision ultrasonic lung function detector and detection method thereof | |
| JP4561088B2 (en) | Ultrasonic flow meter | |
| CN103226033A (en) | An ultrasonic flowmeter | |
| CN110515082B (en) | Automatic range finding system based on ultrasonic wave | |
| CN112903043B (en) | Multichannel ultrasonic flowmeter system | |
| JP4760115B2 (en) | Fluid flow measuring device | |
| CN102023038B (en) | Ultrasonic measurement method for pipeline flux | |
| CN116295149A (en) | Pipeline bubble size measurement system based on time difference type ultrasonic flowmeter | |
| JP4153721B2 (en) | Ultrasonic flowmeter and self-diagnosis method of ultrasonic flowmeter | |
| Ma | Ultrasonic Gas Flowmeter Based on Dynamic Reference Waveform Cross-Correlation Algorithm | |
| JP7343350B2 (en) | Ultrasonic flow meter and flow measurement method | |
| JP3624743B2 (en) | Ultrasonic flow meter | |
| JPH03233395A (en) | Sound wavepropagation time measuring method | |
| CN105486429A (en) | Ultrasonic wave heat meter based on filtering algorithm | |
| JP2002013958A (en) | Ultrasonic flow meter | |
| CN116338240B (en) | Ultrasonic liquid flow velocity measurement method and device based on parabolic fitting | |
| CN115077639B (en) | Measuring method for ultrasonic flowmeter | |
| JP2000283820A (en) | Gas meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |