WO2020107462A1

WO2020107462A1 - Movable platform, electromagnetic flowmeter, and electrode signal amplifier thereof

Info

Publication number: WO2020107462A1
Application number: PCT/CN2018/118725
Authority: WO
Inventors: 孟祥�; 潘仑; 常子敬; 黄稀荻
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2018-11-30
Filing date: 2018-11-30
Publication date: 2020-06-04
Also published as: CN111386444A

Abstract

A movable platform, an electromagnetic flowmeter (72 and 1202), and an electrode signal amplifier thereof. With a first high-pass filter (41) being connected at an input end (411) to a first detection electrode (331, 61, and 851) and being connected at an output end (412) to a first input end (431) of a differential amplifier (43 and 81); and with a second high-pass filter (42) being connected at an input end (421) to a second detection electrode (332, 62, and 852) and being connected at an output end (422) to a second input end (432) of the differential amplifier (43 and 81), the measurement accuracy of the electromagnetic flowmeter (72 and 1202) is increased.

Description

Movable platform, electromagnetic flowmeter and electrode signal amplifier

Technical field

The embodiments of the present invention relate to the technical field of electronics, and in particular, to a movable platform, an electromagnetic flowmeter, and an electrode signal amplifier thereof.

Background technique

Electromagnetic flowmeter is a new type of flow measurement instrument that has been rapidly developed with the development of electronic technology. It uses the principle of electromagnetic induction to measure the flow of conductive fluid according to the electromotive force induced when the conductive fluid passes through an external magnetic field.

Electrode electromagnetic flowmeter is a commonly used electromagnetic flowmeter. In the prior art, the electrode electromagnetic flowmeter directly inputs the differential signal generated by the two measuring electrodes into a differential amplifier for differential amplification. May cause signal distortion problems.

Summary of the invention

Embodiments of the present invention provide a movable platform, an electromagnetic flowmeter and its electrode signal amplifier to reduce signal distortion and improve the measurement accuracy of the electromagnetic flowmeter.

In a first aspect, an embodiment of the present invention provides an electrode signal amplifier for an electromagnetic flowmeter, including:

The first high-pass filter, the second high-pass filter and the differential amplifier;

Wherein, the input end of the first high-pass filter is connected to the first detection electrode, and the output end of the first high-pass filter is connected to the first input end of the differential amplifier;

The input end of the second high-pass filter is connected to the second detection electrode, and the output end of the second high-pass filter is connected to the second input end of the differential amplifier;

A polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, and the cutoff frequency of the first high-pass filter and the second high-pass filter is greater than or equal to the change frequency of the polarization voltage.

In a second aspect, an embodiment of the present invention provides an electromagnetic flowmeter, including:

A first detection electrode, a second detection electrode, a first high-pass filter, a second high-pass filter and a differential amplifier;

In a third aspect, an embodiment of the present invention provides a movable platform, including: a platform body and an electromagnetic flowmeter mounted on the platform body;

Wherein, the electromagnetic flowmeter includes:

According to a fourth aspect, an embodiment of the present invention provides an electrode signal amplifier for an electromagnetic flowmeter, including:

Differential amplifier, high-pass filter and first power supply;

The first power supply is connected to the differential amplifier, the first power supply is used to power the differential amplifier, and the power supply voltage range of the first power supply is greater than a preset range;

The first input terminal of the differential amplifier is connected to the first detection electrode;

The second input terminal of the differential amplifier is connected to the second detection electrode;

The output terminal of the differential amplifier is connected to the high-pass filter.

According to a fifth aspect, an embodiment of the present invention provides an electromagnetic flowmeter, including:

A first detection electrode, a second detection electrode, a differential amplifier, a high-pass filter and a first power supply;

Wherein, the first power supply is connected to the differential amplifier, the first power supply is used to power the differential amplifier, and the power supply voltage range of the first power supply is greater than a preset range;

According to a sixth aspect, an embodiment of the present invention provides a movable platform, including: a platform body and an electromagnetic flowmeter mounted on the platform body;

Wherein, the electromagnetic flowmeter includes:

The movable platform, the electromagnetic flowmeter and the electrode signal amplifier provided by the embodiment of the present invention are connected to the first detection electrode by setting the input end of the first high-pass filter, and the output end of the first high-pass filter is connected to the first of the differential amplifier The input terminal is connected, the input terminal of the second high-pass filter is connected to the second detection electrode, and the output terminal of the second high-pass filter is connected to the second input terminal of the differential amplifier, wherein the electrode of the electromagnetic flowmeter and the conductive fluid are generated Polarization voltage, the cutoff frequency of the first high-pass filter and the second high-pass filter is greater than or equal to the change frequency of the polarization voltage, the two high-pass filters can filter out the electrochemical reaction between the electrode of the electromagnetic flowmeter and the conductive fluid The low-frequency interference of the polarization voltage reduces the signal distortion and improves the measurement accuracy of the electromagnetic flowmeter.

BRIEF DESCRIPTION

In order to more clearly explain the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings used in the embodiments or the description of the prior art. Obviously, the drawings in the following description are some of the present invention. For the embodiment, for those of ordinary skill in the art, without paying any creative labor, other drawings may be obtained based on these drawings.

FIG. 1 is a schematic architectural diagram of an unmanned aerial system according to an embodiment of the present invention;

2 is a schematic structural diagram of an unmanned aerial system according to an embodiment of the present invention;

3 is a schematic structural diagram of an electrode type electromagnetic flowmeter provided by an embodiment of the present invention;

4 is a schematic structural diagram of an electrode signal amplifier of an electromagnetic flowmeter provided by an embodiment of the present invention;

5 is a schematic structural diagram of an electrode signal amplifier of another electromagnetic flowmeter provided by an embodiment of the present invention;

6 is a schematic structural diagram of an electromagnetic flowmeter provided by an embodiment of the present invention;

7 is a schematic structural diagram of a movable platform provided by an embodiment of the present invention;

8 is a schematic structural diagram of an electrode signal amplifier of another electromagnetic flowmeter provided by the implementation of the present invention;

9 is a schematic structural diagram of another electrode signal amplifier of an electromagnetic flowmeter provided by the implementation of the present invention;

10 is a schematic structural diagram of yet another electromagnetic flowmeter provided by an embodiment of the present invention;

11 is a schematic structural diagram of yet another electromagnetic flowmeter provided by the implementation of the present invention;

12 is a schematic structural diagram of another movable platform provided by an embodiment of the present invention;

13 is a schematic diagram of the effect of the prior art;

14 is a schematic diagram of the effect of using the embodiment of the present invention

detailed description

To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

It should be noted that when a component is said to be "fixed" to another component, it can be directly on another component or it can also exist in a centered component. When a component is considered to be "connected" to another component, it can be directly connected to another component or there can be centered components at the same time.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention. The terminology used in the description of the present invention herein is for the purpose of describing specific embodiments, and is not intended to limit the present invention. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

The following describes some embodiments of the present invention in detail with reference to the accompanying drawings. In the case of no conflict, the following embodiments and the features in the embodiments can be combined with each other.

The embodiments of the present invention provide a movable platform, an electromagnetic flowmeter and its electrode signal amplifier. Among them, the electromagnetic flowmeter can be used to measure the flow of any conductive fluid. For example, electromagnetic flowmeters can be installed in plant protection machinery and equipment to measure the flow of pesticides, water, and liquid fertilizers. Among them, plant protection machinery and equipment can be plant protection drones, self-service robots, tractor-supported plant protection machinery, and self-propelled Plant protection machinery and equipment, etc. Electromagnetic flowmeters can be installed in transportation equipment to measure the flow of gasoline or other liquid energy sources. The electromagnetic flowmeter can be equipped with a liquid circulation system, such as a heating and cooling system. The electromagnetic flowmeter can also be installed on a movable platform, such as a drone, an unmanned boat, an unmanned car, a robot, etc. The drone may be, for example, a rotorcraft, for example, a multi-rotor aircraft propelled by multiple propulsion devices through air. In this regard, the embodiments of the present invention are not limited thereto.

FIG. 1 is a schematic architectural diagram of an unmanned aerial system according to an embodiment of the present invention. 2 is a schematic structural diagram of an unmanned aerial system according to an embodiment of the present invention. In this embodiment, a rotary-wing UAV is taken as an example for description.

The unmanned aerial system 100 may include a drone 110, a display device 130, and a control terminal 140. The UAV 110 may include a power system 150, a flight control system 160, a rack, and a gimbal 120 carried on the rack. The drone 110 can communicate wirelessly with the control terminal 140 and the display device 130.

The rack may include a fuselage and a tripod (also called landing gear). The fuselage may include a center frame and one or more arms connected to the center frame, the one or more arms extending radially from the center frame. The tripod is connected to the fuselage and is used to support the UAV 110 when it lands.

The power system 150 may include one or more electronic governors (abbreviated as electric governors) 151, one or more propellers 153, and one or more motors 152 corresponding to the one or more propellers 153, wherein the motor 152 is connected to Between the electronic governor 151 and the propeller 153, the motor 152 and the propeller 153 are disposed on the arm of the drone 110; the electronic governor 151 is used to receive the driving signal generated by the flight control system 160 and provide driving according to the driving signal The current is given to the motor 152 to control the rotation speed of the motor 152. The motor 152 is used to drive the propeller to rotate, thereby providing power for the flight of the drone 110, which enables the drone 110 to achieve one or more degrees of freedom of movement. In some embodiments, the drone 110 may rotate about one or more rotation axes. For example, the rotation axis may include a roll axis (Roll), a yaw axis (Yaw), and a pitch axis (Pitch). It should be understood that the motor 152 may be a DC motor or an AC motor. In addition, the motor 152 may be a brushless motor or a brush motor.

The flight control system 160 may include a flight controller 161 and a sensing system 162. The sensing system 162 is used to measure the attitude information of the drone, that is, the position information and status information of the drone 110 in space, for example, three-dimensional position, three-dimensional angle, three-dimensional velocity, three-dimensional acceleration, and three-dimensional angular velocity. The sensing system 162 may include, for example, at least one of a gyroscope, an ultrasonic sensor, an electronic compass, an inertial measurement unit (Inertial Measurement Unit, IMU), a visual sensor, a global navigation satellite system, and a barometer. For example, the global navigation satellite system may be a global positioning system (Global Positioning System, GPS). The flight controller 161 is used to control the flight of the drone 110. For example, the flight of the drone 110 can be controlled according to the attitude information measured by the sensor system 162. It should be understood that the flight controller 161 may control the drone 110 according to pre-programmed program instructions, or may control the drone 110 by responding to one or more control instructions from the control terminal 140.

The operating system 120 may include one or more power components 122, the operating system may further include multiple operating components 123, and the electromagnetic flowmeter 124 may be installed in the operating system to measure the flow rate of the conductive fluid in the operating system, for example, the operating components 123 is a spray head for spraying water or pesticide, and the electromagnetic flowmeter 124 is used for measuring the flow rate of water or pesticide flowing to the spray head. The power component 122 can provide work power for the work component. The flight controller 161 may control the movement of the operating system 120 through the power component 122. Optionally, the operating system 120 may further include a controller for controlling the motion of the operating system 120 by controlling the power component 122. It should be understood that the operating system 120 may be independent of the drone 110 or may be a part of the drone 110. It should be understood that the power component 122 may be a DC power component or an AC power component. For example, the power component 122 may be a motor, a cylinder, or a water pump. It should also be understood that the working part 123 may be located at the top of the drone or at the bottom of the drone.

The display device 130 is located on the ground end of the unmanned aerial system 100, can communicate with the drone 110 in a wireless manner, and can be used to display the attitude information of the drone 110. In addition, the image captured by the imaging device may also be displayed on the display device 130. It should be understood that the display device 130 may be an independent device or may be integrated in the control terminal 140.

The control terminal 140 is located at the ground end of the unmanned aerial system 100, and can communicate with the drone 110 in a wireless manner for remote manipulation of the drone 110.

In addition, the drone 110 may also be equipped with a speaker (not shown in the figure), which is used to play audio files. The speaker may be directly fixed on the drone 110 or may be mounted on the gimbal 120.

It should be understood that the above naming of the components of the UAV system is for identification purposes only, and should not be construed as limiting the embodiments of the present invention.

The electromagnetic flowmeters described in the embodiments of the present invention refer to electrode-type electromagnetic flowmeters.

The structure of the electrode-type electromagnetic flowmeter is shown in FIG. 3, which is a schematic structural diagram of an electrode-type electromagnetic flowmeter provided by an embodiment of the present invention. The structure mainly includes: a magnetic circuit system 31, a measurement catheter 32, and electrodes And the differential amplifier 34, wherein the electrodes include a first detection electrode 331 and a second detection electrode 332.

The role of the magnetic circuit system 31 is to generate a uniform DC or AC magnetic field. The function of the measuring catheter 32 is to let the conductive fluid under test pass. The role of the electrode is to draw an induced potential signal that is proportional to the measurement. The function of the differential amplifier 34 is to amplify the induced potential signal to reduce the interference of other factors.

The working principle of the electrode type electromagnetic flowmeter is as follows:

Based on Faraday's law of electromagnetic induction, when a conductive fluid flows through the magnetic field generated by the magnetic circuit system, an induced potential signal proportional to the volume flow is generated between a pair of electrodes (ie, the first detection electrode and the second detection electrode).

Among them, the direction of the induced potential signal is perpendicular to the flow direction and the magnetic field.

The amplitude of the induced potential signal can be expressed as: E = kBDv, where E is the electromotive force, k is a constant, B is the magnetic flux density, D is the inner diameter of the conductive fluid measurement catheter, and v is the conductive fluid in the conductive fluid measurement catheter at the electrode The average speed of the cross-section axis.

Electrode electromagnetic flowmeter counts the fluid flow by detecting the magnitude of the induced potential signal generated by the electrode induced flow rate change.

However, due to the electrochemical reaction between the electrode and the conductive fluid, a polarization voltage is generated. The polarization voltage is subject to changes in the low frequency of the conductive fluid, the material of the electrode, the temperature of the conductive fluid, and the material of the conductive fluid. Thus, the magnitude of the induced potential signal is affected, causing signal distortion.

Among them, the polarization voltage refers to the potential difference between the surface of the metal and the fluid when the metal reacts with the fluid when the metal is in the fluid.

In the embodiments of the present invention, high-pass filters are respectively connected to the two input terminals of the differential amplifier to filter out the low-frequency interference of the polarization voltage generated by the electrochemical reaction between the electrode and the conductive fluid, thereby reducing signal distortion and improving The accuracy of electromagnetic flowmeter measurement.

4 is a schematic structural diagram of an electrode signal amplifier of an electromagnetic flowmeter provided by an embodiment of the present invention. As shown in FIG. 4, the circuit of this embodiment includes: a first high-pass filter 41, a second high-pass filter 42 and a differential Amplifier 43;

The input terminal 411 of the first high-pass filter 41 is connected to the first detection electrode, and the output terminal 412 of the first high-pass filter 41 is connected to the first input terminal 431 of the differential amplifier 43;

The input terminal 421 of the second high-pass filter 42 is connected to the second detection electrode, and the output terminal 422 of the second high-pass filter 42 is connected to the second input terminal 432 of the differential amplifier 43.

Among them, a polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid; the frequency of change of the polarization voltage is affected by at least one of the following: the sudden change of the flow rate of the conductive fluid, the material of the electrode of the electromagnetic flowmeter, the conductivity The temperature of the fluid, the material of the conductive fluid.

The cutoff frequencies of the first high-pass filter 41 and the second high-pass filter 42 of this embodiment are greater than or equal to the change frequency of the polarization voltage.

Optionally, the change frequency of the polarization voltage may be 8 Hz, 7.5 Hz, 5 Hz, or 2 Hz, etc., correspondingly, the cutoff frequencies of the first high-pass filter and the second high-pass filter are both set to be greater than or equal 8 Hz, 7.5 Hz, 5 Hz, or 2 Hz, etc. For this, the embodiments of the present invention are not limited.

In the electrode signal amplifier of this embodiment, the input terminal of the first high-pass filter is connected to the first detection electrode, the output terminal of the first high-pass filter is connected to the first input terminal of the differential amplifier, and the input of the second high-pass filter The terminal is connected to the second detection electrode, the output of the second high-pass filter is connected to the second input of the differential amplifier, wherein a polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, the first high-pass filter and the first The cutoff frequency of the second high-pass filter is greater than or equal to the change frequency of the polarization voltage. When the conductive fluid flows through the magnetic field generated by the magnetic circuit system, an induced potential signal proportional to the volume flow is generated between the first detection electrode and the second detection electrode, and the first detection electrode and the second detection electrode electrochemically react with the conductive fluid The reaction generates a low-frequency polarized voltage signal; the induced potential signal is superimposed on a low-frequency polarized voltage signal, and first passes through the first high-pass filter and the second high-pass filter to filter out the low-frequency polarized voltage signal, and the induced potential The signal passes through and enters the differential amplifier to be amplified, thereby reducing the influence of the low-frequency polarization voltage signal on the induced potential signal, reducing the signal distortion, and improving the accuracy of the electromagnetic flowmeter measurement.

FIG. 5 is a schematic structural diagram of an electrode signal amplifier of another electromagnetic flowmeter provided by an embodiment of the present invention. FIG. 5 is based on the embodiment shown in FIG. 4, the first high-pass filter and the second high-pass filter pass through the RC High-pass filter implementation, in which the capacitance and resistance of the RC high-pass filter are determined according to the cut-off frequency of the RC high-pass filter;

Among them, the capacitance value, resistance value and cutoff frequency satisfy the following relationship:

f=1/(2πRC)

Wherein, f is a cutoff frequency, R is a resistance value, and C is a capacitance value.

In this embodiment, the high-pass filter is realized by the RC high-pass filter, and its circuit structure is simple, and the implementation cost is low. The low-frequency polarized voltage signal is filtered by an RC high-pass filter, and the induced potential signal passes through and enters the differential amplifier to be amplified, thereby reducing the influence of the low-frequency polarized voltage signal on the induced potential signal, reducing signal distortion, and improving The accuracy of electromagnetic flowmeter measurement.

6 is a schematic structural diagram of an electromagnetic flowmeter provided by an embodiment of the present invention, the electromagnetic flowmeter includes: a first detection electrode 61, a second detection electrode 62, a first high-pass filter 41, a second high-pass filter 42 and Differential amplifier 43;

The first high-pass filter 41, the second high-pass filter 42 and the differential amplifier 43;

The input terminal 411 of the first high-pass filter 41 is connected to the first detection electrode 61, and the output terminal 412 of the first high-pass filter 41 is connected to the first input terminal 431 of the differential amplifier 43;

The input terminal 421 of the second high-pass filter 42 is connected to the second detection electrode 62, and the output terminal 422 of the second high-pass filter 42 is connected to the second input terminal 432 of the differential amplifier 43.

In the electromagnetic flowmeter of this embodiment, the input end of the first high-pass filter is connected to the first detection electrode, the output end of the first high-pass filter is connected to the first input end of the differential amplifier, and the input of the second high-pass filter The terminal is connected to the second detection electrode, the output of the second high-pass filter is connected to the second input of the differential amplifier, wherein a polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, the first high-pass filter and the first The cutoff frequency of the second high-pass filter is greater than or equal to the change frequency of the polarization voltage. When the conductive fluid flows through the magnetic field generated by the magnetic circuit system, an induced potential signal proportional to the volume flow is generated between the first detection electrode and the second detection electrode, and the first detection electrode and the second detection electrode electrochemically react with the conductive fluid The reaction generates a low-frequency polarized voltage signal; the induced potential signal is superimposed on a low-frequency polarized voltage signal, and first passes through the first high-pass filter and the second high-pass filter to filter out the low-frequency polarized voltage signal, and the induced potential The signal passes through and enters the differential amplifier to be amplified, thereby reducing the influence of the low-frequency polarization voltage signal on the induced potential signal, reducing the signal distortion, and improving the accuracy of the electromagnetic flowmeter measurement.

7 is a schematic structural diagram of a movable platform provided by an embodiment of the present invention, a platform body 71 and an electromagnetic flow meter 72 installed on the platform body;

Wherein, the electromagnetic flowmeter 72 shown in FIG. 6 includes:

The first detection electrode 61, the second detection electrode 62, the first high-pass filter 41, the second high-pass filter 42 and the differential amplifier 43;

In the movable platform of this embodiment, the input terminal of the first high-pass filter is connected to the first detection electrode, the output terminal of the first high-pass filter is connected to the first input terminal of the differential amplifier, and the input of the second high-pass filter The terminal is connected to the second detection electrode, the output of the second high-pass filter is connected to the second input of the differential amplifier, wherein a polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, the first high-pass filter and the first The cutoff frequency of the second high-pass filter is greater than or equal to the change frequency of the polarization voltage. When the conductive fluid flows through the magnetic field generated by the magnetic circuit system, an induced potential signal proportional to the volume flow is generated between the first detection electrode and the second detection electrode, and the first detection electrode and the second detection electrode electrochemically react with the conductive fluid The reaction generates a low-frequency polarized voltage signal; the induced potential signal is superimposed on a low-frequency polarized voltage signal, and first passes through the first high-pass filter and the second high-pass filter to filter out the low-frequency polarized voltage signal, and the induced potential The signal passes through and enters the differential amplifier to be amplified, thereby reducing the influence of the low-frequency polarization voltage signal on the induced potential signal, reducing the signal distortion, and improving the accuracy of the electromagnetic flowmeter measurement.

8 is a schematic structural diagram of an electrode signal amplifier of another electromagnetic flowmeter provided by the implementation of the present invention, including:

Differential amplifier 81, high-pass filter 82 and first power supply 83;

The first power supply 83 is connected to the differential amplifier 81, and the first power supply 83 is used to supply power to the differential amplifier 81, and the power supply voltage range of the first power supply is greater than the preset range;

The first input terminal 811 of the differential amplifier 81 is connected to the first detection electrode;

The second input terminal 812 of the differential amplifier 81 is connected to the second detection electrode;

The output 813 of the differential amplifier 81 is connected to the high-pass filter 82.

When the conductive fluid flows through the magnetic field generated by the magnetic circuit system, an induced potential signal proportional to the volume flow is generated between the first detection electrode and the second detection electrode, and the first detection electrode and the second detection electrode electrochemically react with the conductive fluid The reaction generates a low-frequency polarized voltage signal; the induced potential signal is superimposed on a low-frequency polarized voltage signal, and the preset range allows the induced potential signal and the polarized voltage signal to be amplified and output by the differential amplifier without distortion.

Optionally, the power supply voltage range of the first power supply is 24V-36V.

In the electrode signal amplifier of this embodiment, by increasing the power supply voltage range of the power supply of the differential amplifier, the induced potential signal and the polarization voltage signal are not distorted and output through the differential amplifier, and then the amplified pole is passed through the high-pass filter The voltage signal is filtered out, thereby reducing the distortion of the signal and improving the accuracy of the electromagnetic flowmeter measurement.

9 is a schematic structural diagram of an electrode signal amplifier of another electromagnetic flowmeter provided by the implementation of the present invention. FIG. 9 is based on the embodiment shown in FIG. 8 and further includes: a second power supply 84, wherein, The second power supply 84 is connected to the differential amplifier 81. The second power supply 84 and the first power supply are used to jointly power the differential amplifier. The common power supply voltage range of the second power supply and the first power supply is greater than the first The supply voltage range of the power supply.

Optionally, the first power supply 83 and the second power supply 84 are connected in series, and the position between the two is set to a voltage zero point.

The electrode signal amplifier of this embodiment increases the power supply voltage range by setting the dual power supply, that is, the first power supply and the second power supply, so that the induced potential signal and the polarization voltage signal are not distorted and then amplified and output by the differential amplifier, and then The amplified polarized voltage signal is filtered out by a high-pass filter, thereby reducing the distortion of the signal and improving the measurement accuracy of the electromagnetic flowmeter.

10 is a schematic structural diagram of yet another electromagnetic flowmeter provided by an embodiment of the present invention, including: a first detection electrode 851, a second detection electrode 852, a differential amplifier 81, a high-pass filter 82, and a first power supply 83;

The first power supply 83 is connected to the differential amplifier 81. The first power supply 83 is used to supply power to the differential amplifier 81. The power supply voltage range of the first power supply 83 is greater than the preset range;

The first input terminal of the differential amplifier 81 is connected to the first detection electrode 851;

The second input terminal of the differential amplifier 81 is connected to the second detection electrode 852;

The output of the differential amplifier 81 is connected to the high-pass filter.

In the electromagnetic flowmeter of this embodiment, by increasing the power supply voltage range of the power supply of the differential amplifier, the induced potential signal and the polarization voltage signal are amplified by the differential amplifier without distortion and output. Then, the amplified polarized voltage signal is filtered out by a high-pass filter, thereby reducing the distortion of the signal and improving the measurement accuracy of the electromagnetic flowmeter.

11 is a schematic structural diagram of yet another electromagnetic flowmeter provided by the implementation of the present invention. FIG. 11 is based on the embodiment shown in FIG. 10, and further includes: a second power supply 84, wherein the second power supply 84 is connected to the differential amplifier 81, and the second power supply 84 and the first power supply are used to jointly power the differential amplifier, and the common power supply voltage range of the second power supply and the first power supply is greater than that of the first power supply voltage range.

In the electromagnetic flowmeter of this embodiment, the dual power supply is provided, that is, the first power supply and the second power supply are provided to increase the power supply voltage range, so that the induced potential signal and the polarization voltage signal are amplified by the differential amplifier and output without distortion. Then, the amplified polarized voltage signal is filtered out by a high-pass filter, thereby reducing the distortion of the signal and improving the measurement accuracy of the electromagnetic flowmeter.

FIG. 12 is a schematic structural diagram of another movable platform provided by an embodiment of the present invention. FIG. 12 includes: a platform body 1201 and an electromagnetic flowmeter 1202 installed on the platform body;

Wherein, the electromagnetic flowmeter 1202 as shown in FIG. 10 or FIG. 11 includes:

The first detection electrode 851, the second detection electrode 852, the differential amplifier 81, the high-pass filter 82, and the first power supply 83;

The first power supply 83 is connected to the differential amplifier 81, the first power supply 83 is used to supply power to the differential amplifier 81, and the power supply voltage range of the first power supply 83 is greater than the preset range;

In the movable platform of this embodiment, by increasing the power supply voltage range of the power supply of the differential amplifier, the induced potential signal and the polarization voltage signal are amplified by the differential amplifier without distortion and output. Then, the amplified polarized voltage signal is filtered out by a high-pass filter, thereby reducing the distortion of the signal and improving the measurement accuracy of the electromagnetic flowmeter.

On the basis of the embodiment shown in FIG. 12, further, the electromagnetic flowmeter further includes: a second power supply 84, wherein the second power supply 84 is connected to the differential amplifier 81, and the second power supply 84 is used in conjunction with the first power supply In order to power the differential amplifier together, the common power supply voltage range of the second power supply and the first power supply is greater than the power supply voltage range of the first power supply.

In the mobile platform of this embodiment, the dual power supply is provided, that is, the first power supply and the second power supply are provided to increase the power supply voltage range, so that the induced potential signal and the polarization voltage signal are not distorted and output after being amplified by the differential amplifier. Then, the amplified polarized voltage signal is filtered out by a high-pass filter, thereby reducing the distortion of the signal and improving the measurement accuracy of the electromagnetic flowmeter.

Embodiments of the present invention also provide schematic diagrams for comparing the effects of using the technical solutions of the prior art and the technical solutions of the present invention, as shown in FIGS. 13 and 14, wherein FIG. 13 is a schematic diagram of the effects of the prior art and FIG. 14 Using the schematic diagram of the effect of the embodiment of the present invention, it can be seen from FIG. 13 that, in the prior art, the instantaneous fluid velocity changes from 0 to some, and the polarization voltage changes, resulting in signal distortion. As can be seen from FIG. In the technical solution of the embodiment of the present invention, at a moment when the fluid velocity changes from 0 to some, the polarization voltage changes, but the distortion of the signal is reduced.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than limiting it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not deviate from the essence of the corresponding technical solutions of the technical solutions of the embodiments of the present invention. range.

Claims

An electrode signal amplifier of an electromagnetic flowmeter is characterized in that it includes:

The first high-pass filter, the second high-pass filter and the differential amplifier;

Wherein, the input end of the first high-pass filter is connected to the first detection electrode, and the output end of the first high-pass filter is connected to the first input end of the differential amplifier;

The input end of the second high-pass filter is connected to the second detection electrode, and the output end of the second high-pass filter is connected to the second input end of the differential amplifier;

A polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, and the cutoff frequency of the first high-pass filter and the second high-pass filter is greater than or equal to the change frequency of the polarization voltage.
The electrode signal amplifier according to claim 1, wherein the change frequency of the polarization voltage is affected by at least one of the following:

The sudden change in the flow rate of the conductive fluid, the material of the electrode of the electromagnetic flowmeter, the temperature of the conductive fluid, and the material of the conductive fluid.
The electrode signal amplifier according to claim 1 or 2, wherein the cutoff frequencies of the first high-pass filter and the second high-pass filter are both greater than or equal to 8 Hz.
The electrode signal amplifier according to claim 1 or 2, wherein the cutoff frequencies of the first high-pass filter and the second high-pass filter are both greater than or equal to 7.5 Hz.
The electrode signal amplifier according to claim 1 or 2, wherein the cutoff frequencies of the first high-pass filter and the second high-pass filter are both greater than or equal to 5 Hz.
The electrode signal amplifier according to claim 1, wherein the first high-pass filter and the second high-pass filter are RC high-pass filters, and the capacitance and resistance values of the RC high-pass filter are based on the RC The cut-off frequency of the high-pass filter is determined.
An electromagnetic flowmeter is characterized by comprising:

A first detection electrode, a second detection electrode, a first high-pass filter, a second high-pass filter and a differential amplifier;

Wherein, the input end of the first high-pass filter is connected to the first detection electrode, and the output end of the first high-pass filter is connected to the first input end of the differential amplifier;

The input end of the second high-pass filter is connected to the second detection electrode, and the output end of the second high-pass filter is connected to the second input end of the differential amplifier;

A polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, and the cutoff frequency of the first high-pass filter and the second high-pass filter is greater than or equal to the frequency of change of the polarization voltage.
A movable platform, characterized in that it includes: a platform body and an electromagnetic flowmeter mounted on the platform body;

Wherein, the electromagnetic flowmeter includes:

A first detection electrode, a second detection electrode, a first high-pass filter, a second high-pass filter and a differential amplifier;

Wherein, the input end of the first high-pass filter is connected to the first detection electrode, and the output end of the first high-pass filter is connected to the first input end of the differential amplifier;

The input end of the second high-pass filter is connected to the second detection electrode, and the output end of the second high-pass filter is connected to the second input end of the differential amplifier;

A polarization voltage is generated between the electrode of the electromagnetic flowmeter and the conductive fluid, and the cutoff frequency of the first high-pass filter and the second high-pass filter is greater than or equal to the change frequency of the polarization voltage.
An electrode signal amplifier of an electromagnetic flowmeter is characterized in that it includes:

Differential amplifier, high-pass filter and first power supply;

The first power supply is connected to the differential amplifier, the first power supply is used to power the differential amplifier, and the power supply voltage range of the first power supply is greater than a preset range;

The first input terminal of the differential amplifier is connected to the first detection electrode;

The second input terminal of the differential amplifier is connected to the second detection electrode;

The output terminal of the differential amplifier is connected to the high-pass filter.
The electrode signal amplifier according to claim 9, wherein the power supply voltage range of the first power supply is 24V-36V.
The electrode signal amplifier according to claim 9, further comprising:

A second power supply, the second power supply is connected to the differential amplifier, the second power supply and the first power supply are used to jointly power the differential amplifier, the second power supply and the The common power supply voltage range of the first power supply is larger than the power supply voltage range of the first power supply.
The electrode signal amplifier according to claim 11, wherein the first power supply and the second power supply are connected in series, and the position between the two is set to a voltage zero point.
An electromagnetic flowmeter is characterized by comprising:

A first detection electrode, a second detection electrode, a differential amplifier, a high-pass filter and a first power supply;

Wherein, the first power supply is connected to the differential amplifier, the first power supply is used to power the differential amplifier, and the power supply voltage range of the first power supply is greater than a preset range;

The first input terminal of the differential amplifier is connected to the first detection electrode;

The second input terminal of the differential amplifier is connected to the second detection electrode;

The output terminal of the differential amplifier is connected to the high-pass filter.
The electromagnetic flowmeter according to claim 13, wherein the power supply voltage range of the first power supply is 24V-36V.
The electromagnetic flowmeter of claim 13, further comprising:

A second power supply, the second power supply is connected to the differential amplifier, the second power supply and the first power supply are used to jointly power the differential amplifier, the second power supply and the The common power supply voltage range of the first power supply is larger than the power supply voltage range of the first power supply.
The electromagnetic flowmeter according to claim 15, wherein the first power supply and the second power supply are connected in series, and the position between the two is set to a voltage zero point.
A movable platform, characterized in that it includes: a platform body and an electromagnetic flowmeter mounted on the platform body;

Wherein, the electromagnetic flowmeter includes:

A first detection electrode, a second detection electrode, a differential amplifier, a high-pass filter and a first power supply;

Wherein, the first power supply is connected to the differential amplifier, the first power supply is used to power the differential amplifier, and the power supply voltage range of the first power supply is greater than a preset range;

The first input terminal of the differential amplifier is connected to the first detection electrode;

The second input terminal of the differential amplifier is connected to the second detection electrode;

The output terminal of the differential amplifier is connected to the high-pass filter.
The movable platform according to claim 17, wherein the power supply voltage range of the first power supply is 24V-36V.
The movable platform according to claim 17, further comprising:

A second power supply, the second power supply is connected to the differential amplifier, the second power supply and the first power supply are used to jointly power the differential amplifier, the second power supply and the The common power supply voltage range of the first power supply is larger than the power supply voltage range of the first power supply.
The movable platform according to claim 19, wherein the first power supply and the second power supply are connected in series, and the position between the two is set to a voltage zero point.