CN113049868A - Alternating current and direct current measuring device and measuring method - Google Patents
Alternating current and direct current measuring device and measuring method Download PDFInfo
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- G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
- G01R15/205—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices using magneto-resistance devices, e.g. field plates
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Abstract
The invention discloses an alternating current and direct current measuring device and a measuring method, comprising the following steps: the control module comprises a control unit and an analog-to-digital conversion unit, and the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals; the induction modules comprise a plurality of induction modules, the input end of each induction module is connected with the control unit to receive the square wave signal, and the output end of each induction module is connected with the analog-to-digital conversion unit to generate a corresponding induction output voltage signal according to the level state of the square wave signal; the current measuring device does not need to eliminate residual magnetism through key operation, the measured value can directly reflect the actual current value to be measured, and the measurement accuracy is high; the control module outputs square wave signals to the induction module, so that the influence of earth magnetic field disturbance is eliminated, and the value of the current to be measured can be accurately measured.
Description
Technical Field
The invention relates to the technical field of current measurement, in particular to an alternating current and direct current measuring device and a measuring method implemented by the current measuring device.
Background
At present, a binding clip hall current sensing device of an ac/dc clamp meter on the market needs to be installed at a notch of an iron core (silicon steel sheet, permalloy), when the binding clip is clamped into a current lead to be measured, current passes through the lead to generate a magnetic field, the iron core gathers the magnetic field at the notch and is sensed by a hall current sensor, so that corresponding voltage is sensed, a differential amplifier outputs a voltage signal, the voltage signal and a primary side current meet a certain linear relation, and an analog-to-digital converter converts the voltage signal into a digital signal to calculate the size of the measured current, so that the purpose of measuring the current is achieved. However, the AC/DC clamp meter has the following disadvantages that (1) the iron core belongs to a magnetic material, when the DC heavy current is measured, the iron core has residual magnetism, the residual magnetism is sensed by the Hall current sensor, a certain bias voltage is output, if the influence of the residual magnetism is not eliminated, the voltage value with bias voltage components is output when the DC current is measured next time, and therefore the calculated current value cannot actually reflect the primary side current value, and an inaccurate current value is displayed; (2) because the iron core has weight, when the iron core falls, the position of the Hall current sensing device at the notch of the iron core (silicon steel sheet, permalloy) can generate mechanical offset, so that the induced voltage value can also change correspondingly, and when the current value calculated by the voltage value is serious, the current value is greatly different from the primary side current value, and the wrong current value can be displayed; (3) under the condition of zero current, due to earth magnetic field disturbance, the Hall current sensor can sense different bias voltages due to different geographic positions, the influence of the bias voltages is eliminated by keys, the correct current value can be displayed, the operation is complex, and if the operation is wrong, the current value is directly caused to have deviation in measurement.
Disclosure of Invention
The present invention is directed to solving the above problems, and an object of the present invention is to provide an ac/dc current measuring device.
The present invention also aims to provide an ac/dc current measuring method.
The technical scheme adopted by the invention for realizing the purpose is as follows:
an ac/dc current measuring device comprising:
the control module comprises a control unit and an analog-to-digital conversion unit, and the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals;
the sensing modules comprise a plurality of sensing modules, the input end of each sensing module is connected with the control unit to receive the square wave signal, and the output end of each sensing module is connected with the analog-to-digital conversion unit to generate a corresponding sensing output voltage signal according to the level state of the square wave signal;
the first processing unit is connected between the output end of the sensing module and the analog-to-digital conversion unit and used for receiving the sensing output signal and processing the sensing output voltage signal into a corresponding positive sensitivity output voltage signal and a corresponding negative sensitivity output voltage signal;
the analog-to-digital conversion unit receives and processes the positive sensitivity output voltage signal and the negative sensitivity output voltage signal and then outputs the signals to the control unit, and the control unit outputs the value of the current to be measured.
Preferably, the current to be measured Ip is:
wherein the content of the first and second substances,
a. b is a positive integer greater than 1, x (n) is a sensing output voltage signal of each sensing module when the square wave signal is at a high level, and y (i) is a sensing output voltage signal of each sensing module when the square wave signal is at a low level.
Preferably, the control module further comprises a display unit, and the display unit is connected with the control unit to display the value of the current to be measured.
Preferably, the first processing unit includes:
the inverting input end of the first operational amplifier is connected with one output end of each sensing module, the non-inverting input end of the first operational amplifier is connected with the other output end of the sensing module, and the output end of the first operational amplifier is connected with the analog-to-digital conversion unit.
Preferably, the sensing module includes:
a magnetic resistance variation unit, the resistance value of which varies with the magnetic field generated by the current to be measured;
the bridge driving unit is connected with the magnetic resistance change unit and used for providing a voltage source for the magnetic resistance change unit so as to enable the magnetic resistance change unit to generate a differential voltage signal;
one end of the square wave input unit is connected with the magnetic resistance conversion unit, and the other end of the square wave input unit is connected with the control unit and used for outputting the corresponding induction output voltage signal according to the level state of the square wave signal;
and one end of the second processing unit is connected with the magnetic resistance change unit, and the other end of the second processing unit is connected with the analog-to-digital conversion unit so as to amplify the induction output voltage signal.
Preferably, the magnetoresistance change unit is an AMR magnetoresistance sensor.
Preferably, the second processing unit includes:
the non-inverting input end and the inverting input end of the second operational amplifier are respectively connected with the magnetic resistance change unit;
and the non-inverting input end of the third operational amplifier is connected with the output end of the second operational amplifier, and the output end of the third operational amplifier is connected with the first processing unit and used for increasing bias voltage for the induction output voltage signal.
Preferably, a power end of the second operational amplifier is connected to one end of a digital controller, and the other end of the digital controller is connected to the control unit, so that the control unit sets the amplification factor and the chopping modulation frequency of the second operational amplifier.
Preferably, the bridge driving unit includes:
and one end of the bridge driver circuit is connected with the magnetic resistance change unit, and the other end of the bridge driver circuit is connected with the temperature sensor.
An alternating current and direct current measurement method, comprising:
the control unit outputs a square wave signal;
the sensing modules are close to the current to be measured, the sensing modules receive the square wave signals, and each sensing module respectively outputs a plurality of corresponding sensing output voltage signals according to the high and low level states of the square wave signals;
when the square wave signal is at a high level, a plurality of corresponding induction output voltage signals are processed into positive sensitivity output voltage signals through a first processing unit;
when the square wave signal is at a low level, a plurality of corresponding induction output voltage signals are processed into negative sensitivity output voltage signals through the first processing unit;
and the first processing unit outputs the positive sensitivity output voltage signal and the negative sensitivity output voltage signal to the analog-to-digital conversion unit for processing, and finally outputs a current value to be detected.
The invention has the beneficial effects that: the invention discloses an AC/DC current measuring device, comprising: the control module comprises a control unit and an analog-to-digital conversion unit, and the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals; the induction modules comprise a plurality of induction modules, the input end of each induction module is connected with the control unit to receive the square wave signal, and the output end of each induction module is connected with the analog-to-digital conversion unit to generate a corresponding induction output voltage signal according to the level state of the square wave signal; the first processing unit is connected between the output end of the sensing module and the analog-to-digital conversion unit and used for receiving the sensing output signal and processing the sensing output voltage signal into a corresponding positive sensitivity output voltage signal and a corresponding negative sensitivity output voltage signal; the analog-to-digital conversion unit receives and processes the positive sensitivity output voltage signal and the negative sensitivity output voltage signal and then outputs the signals to the control unit, and the control unit outputs the value of the current to be measured. The induction module is arranged on the tong head, and a traditional current measuring mode of an iron core material is replaced due to the fact that a magnetic material is not adopted, so that the problem of remanence does not exist, the current measuring device does not need to eliminate remanence through key operation, the measured value can directly reflect the actual current value to be measured, and the measuring accuracy is high; the control module outputs square wave signals to the induction module, so that the influence of earth magnetic field disturbance is eliminated, and the value of the current to be measured can be accurately measured.
The invention is further described with reference to the following figures and examples.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of a current measuring device provided by an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a current measuring device according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a first processing unit and a control module according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a sensing module according to an embodiment of the present invention;
FIG. 5 is a first connection diagram of three sensing modules provided by the embodiment of the present invention;
fig. 6 is a second connection diagram of three sensing modules according to an embodiment of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the description of the present invention, it should be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly connected" to another element, there are no intervening elements present.
The alternating current and direct current measuring device does not need an iron core as a magnetic material to increase the magnetic field induction intensity, and the direction of a magnetic field generated by the induction module and the current to be measured is parallel. In the middle of the alternating current-direct current measuring device, the induction module is attached to the clamp head circuit board, then the clamp head circuit board is fixed on the clamp head cover in a screw driving mode, and therefore mechanical position deviation can be avoided when the clamp head circuit board falls, and wrong current values are displayed. In addition, the induction modules are arranged at different positions on the tong head circuit board, and due to the disturbance of the earth magnetic field, the induction modules at different positions induce different bias voltages, and square wave signals are additionally added to eliminate the influence of the bias voltages, so that more accurate current values are obtained.
Referring to fig. 1 to 6, an alternative embodiment of the ac/dc current measuring apparatus includes:
the control module 1 comprises a control unit and an analog-to-digital conversion unit, wherein the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals;
the sensing modules 2 are multiple, the input end of each sensing module 2 is connected with the control unit to receive the square wave signal, and the output end of each sensing module 2 is connected with the analog-to-digital conversion unit to generate a corresponding sensing output voltage signal according to the level state of the square wave signal;
the first processing unit is connected between the output end of the sensing module 2 and the analog-to-digital conversion unit and is used for receiving the sensing output signal and processing the sensing output voltage signal into a corresponding positive sensitivity output voltage signal and a corresponding negative sensitivity output voltage signal;
the analog-to-digital conversion unit receives and processes the positive sensitivity output voltage signal and the negative sensitivity output voltage signal and then outputs the signals to the control unit, and the control unit outputs the value of the current to be measured.
Specifically, the control module 1 is a microprocessor chip, and has a model number of SWM181RCT6-50, wherein the control unit can output a square wave signal with a pulse width of 300ms to each sensing module 2 through the FLIP _ DRV terminal, so as to be used for positive sensitivity sensing and negative sensitivity sensing of the magnetoresistance change unit.
The control module is arranged in the current measuring device, the first processing unit is arranged in the current measuring device, and the induction module is arranged at the head of the current measuring device.
The left and right tong head circuit boards are respectively arranged at the tong head part of the current measuring device, and the induction modules 2 are symmetrically attached to the left and right tong head circuit boards respectively. Therefore, the number of the sensing modules 2 is to be even, and the number of the sensing modules 2 on the left tong head circuit board is to be consistent with the number of the sensing modules 2 on the right tong head circuit board.
The A0, A1 and SYNC ends of the control module 1 are connected with the A0, A1 and SYNC ends of the induction module 2 through the left and right tong head circuit boards, and the amplification factor and the modulation frequency of a second operational amplifier in the induction module 2 are further set through the control module 1; namely, the control module is connected with the induction module through the tong head circuit board, and the induction module is connected with the first processing unit through the tong head circuit board.
The a0 and a1 terminals of the control module 1 control the a0 and a1 terminals of the sensing module 2, wherein the relationship between the amplification factors of the a1 and the a0 terminals and the second operational amplifier is shown in table 1:
TABLE 1 relationship of amplification factor between terminal A1 and terminal A0 and the second operational amplifier
| A1 (level state) | A0 (level state) | Magnification factor |
| 0 | 1 | 20 |
| 1 | 0 | 40 |
| 1 | 1 | 80 |
The SYNC end of the control module 1 controls the SYNC end of the sensing module 2, wherein the relationship between the SYNC end and the modulation frequency of the second operational amplifier is shown in table 2:
TABLE 2 amplification relationship between SYNC terminal and second operational amplifier
| SYNC | Frequency of chopper modulation |
| VDD | Is free of |
| GND | 200KHz |
When the square wave signal generating device is used, the control module 1 is used for setting the amplification factor and the modulation frequency of the second operational amplifier in the induction module 2, and then the control module 1 outputs the square wave signal with the pulse width of 300ms to the induction module 2.
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring apparatus, the current to be measured Ip is:
wherein the content of the first and second substances,
a. b is a positive integer greater than 1, a and b are the sum of the number of the induction modules 2 on the binding clip circuit board, and a is equal to b, x (n) is an induction output voltage signal of each induction module 2 when the square wave signal is at a high level, and y (i) is an induction output voltage signal of each induction module 2 when the square wave signal is at a low level.
Further, when a has a value of 6 and b has a value of 6 (i.e. there are 3 sensing modules 2 on the left tong head circuit board and 3 sensing modules 2 on the right tong head circuit board, there are 6 sensing modules 2 in total, i.e. U1, U2, U3, U4, U5, U6):
when the square wave signal is at high level, the value of the sensing output voltage signal output by the 6 sensing modules 2 is X (n) mV/A, and then
When the square wave signal is at high level, the sensing output voltage signal of the sensing module 2 passes through the first operational amplifier to output a positive sensitivity output voltage signal
Wherein, V(Zheng)Is namely V(Positive sensitivity)And V is_offsetIn order for the earth's magnetic field to affect the bias voltage of the induction module 2,
a bias voltage is added to the sense output voltage signal for the first operational amplifier.
When the square wave signal is at a low level, the value of the sensing output voltage signal output by the 6 sensing modules 2 is y (i) mV/a, then:
when the square wave signal is at low level, the sensing output voltage signal of the sensing module 2 passes through the first operational amplifier to output a negative sensitivity output voltage signal
Wherein, V(negative)Is namely V(negative sensitivity)And V is_offsetIn order for the earth's magnetic field to affect the bias voltage of the induction module 2,
a bias voltage is added to the sense output voltage signal for the first operational amplifier.
From the above, V(negative)Decreasing V(Zheng)Bias voltage V capable of eliminating earth magnetic field_offsetAnd additionally increased bias voltage
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring device, the control module 1 further includes a display unit, and the display unit is connected to the control unit for displaying the value of the current to be measured.
The display unit is an LCD module and an LCD display screen and is used for displaying the numerical value of the current to be measured.
Referring to fig. 1 to 6, in an alternative embodiment, the ac/dc current measuring apparatus includes: a first operational amplifier U7, an inverting input terminal of the first operational amplifier U7 is connected to an output terminal of each of the sensing modules 2, a non-inverting input terminal of the first operational amplifier U7 is connected to another output terminal of the sensing module 2, and an output terminal of the first operational amplifier U7 is connected to the analog-to-digital conversion unit.
First impedances (R1, R2, R3, R4, R5 and R6) are arranged between the inverting input end of the first operational amplifier U7 and the output end of each sensing module 2, and the resistance value of the first impedances is 12K omega. A second impedance R7 is disposed between the inverting input terminal of the first operational amplifier U7 and the output terminal of the first operational amplifier U7, and the resistance of the second impedance R7 is 2K Ω. The non-inverting input terminal of the first operational amplifier U7 is connected in parallel to a third impedance R8 and a fourth impedance R9, the third impedance R8 is connected to an external bias voltage, and the fourth impedance R9 is grounded, wherein the third impedance R8 has a resistance of 10K Ω, and the fourth impedance R9 has a resistance of 10K Ω.
In addition, the first operational amplifier U7 has a model number SGM 8557.
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring apparatus, the sensing module 2 includes:
a magnetic resistance variation unit, the resistance value of which varies with the magnetic field generated by the current to be measured;
the bridge driving unit is connected with the magnetic resistance change unit and used for providing a voltage source for the magnetic resistance change unit so as to enable the magnetic resistance change unit to generate a differential voltage signal;
one end of the square wave input unit is connected with the magnetic resistance conversion unit, and the other end of the square wave input unit is connected with the control unit and used for outputting the corresponding induction output voltage signal according to the level state of the square wave signal;
and one end of the second processing unit is connected with the magnetic resistance change unit, and the other end of the second processing unit is connected with the analog-to-digital conversion unit so as to amplify the induction output voltage signal.
Wherein the square wave input unit is a flipping coil driver.
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring apparatus, the magnetoresistance variation unit is an AMR magnetoresistance sensor. The AMR magnetoresistive sensor comprises a resistance bridge, wherein the resistance of the resistance bridge changes along with the change of a magnetic field.
Referring to fig. 1 to 6, in an alternative embodiment, the ac/dc current measuring apparatus includes:
the non-inverting input end and the inverting input end of the second operational amplifier are respectively connected with the magnetic resistance change unit;
and the non-inverting input end of the third operational amplifier is connected with the output end of the second operational amplifier, and the output end of the third operational amplifier is connected with the first processing unit and used for increasing bias voltage for the induction output voltage signal.
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring apparatus, a power supply terminal of the second operational amplifier is connected to one end of a digital controller, and the other end of the digital controller is connected to the control unit, so that the control unit sets an amplification factor and a chopper modulation frequency of the second operational amplifier.
Referring to fig. 1 to 6, in an alternative embodiment of the ac/dc current measuring apparatus, the bridge driving unit includes:
and one end of the bridge driver circuit is connected with the magnetic resistance change unit, and the other end of the bridge driver circuit is connected with the temperature sensor.
An alternating current and direct current measurement method, comprising:
the control unit outputs a square wave signal;
the plurality of induction modules 2 are close to the current to be measured, the plurality of induction modules 2 receive the square wave signals, and each induction module 2 respectively outputs a plurality of corresponding induction output voltage signals according to the high and low level states of the square wave signals;
when the square wave signal is at a high level, a plurality of corresponding induction output voltage signals are processed into positive sensitivity output voltage signals through a first processing unit;
when the square wave signal is at a low level, a plurality of corresponding induction output voltage signals are processed into negative sensitivity output voltage signals through the first processing unit;
and the first processing unit outputs the positive sensitivity output voltage signal and the negative sensitivity output voltage signal to the analog-to-digital conversion unit for processing, and finally outputs a current value to be detected.
The invention discloses an AC/DC current measuring device, comprising: the control module 1 comprises a control unit and an analog-to-digital conversion unit, wherein the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals; the induction modules 2 comprise a plurality of induction modules 2, the input end of each induction module 2 is connected with the control unit to receive the square wave signal, and the output end of each induction module 2 is connected with the analog-to-digital conversion unit to generate a corresponding induction output voltage signal according to the level state of the square wave signal; the first processing unit is connected between the output end of the sensing module 2 and the analog-to-digital conversion unit and used for receiving the sensing output signal and processing the sensing output voltage signal into a corresponding positive sensitivity output voltage signal and a corresponding negative sensitivity output voltage signal; the analog-to-digital conversion unit receives and processes the positive sensitivity output voltage signal and the negative sensitivity output voltage signal and then outputs the signals to the control unit, and the control unit outputs the value of the current to be measured. The induction module 2 is arranged on the binding clip, and because a magnetic material is not adopted, the traditional mode of measuring current by using an iron core material is replaced, the problem of remanence does not exist, the current measuring device does not need to eliminate remanence through key operation, the measured value can directly reflect the actual current value to be measured, and the measurement accuracy is high; the control module 1 outputs square wave signals to the induction module 2, so that the influence of earth magnetic field disturbance is eliminated, and the numerical value of the current to be measured can be accurately measured.
It should be understood that, in various embodiments of the present invention, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
It should also be understood that, in the embodiment of the present invention, the term "and/or" is only one kind of association relation describing an associated object, and means that three kinds of relations may exist. For example, a and/or B, may represent: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Those skilled in the art can make numerous possible variations and modifications to the present teachings, or modify equivalent embodiments to equivalent variations, without departing from the scope of the present teachings, using the methods and techniques disclosed above. Therefore, all equivalent changes made according to the shape, structure and principle of the present invention without departing from the technical scheme of the present invention shall be covered by the protection scope of the present invention.
Claims (10)
1. An ac/dc current measuring device, comprising:
the control module comprises a control unit and an analog-to-digital conversion unit, and the control unit is connected with the analog-to-digital conversion unit and used for outputting square wave signals;
the sensing modules comprise a plurality of sensing modules, the input end of each sensing module is connected with the control unit to receive the square wave signal, and the output end of each sensing module is connected with the analog-to-digital conversion unit to generate a corresponding sensing output voltage signal according to the level state of the square wave signal;
the first processing unit is connected between the output end of the sensing module and the analog-to-digital conversion unit and used for receiving the sensing output signal and processing the sensing output voltage signal into a corresponding positive sensitivity output voltage signal and a corresponding negative sensitivity output voltage signal;
the analog-to-digital conversion unit receives and processes the positive sensitivity output voltage signal and the negative sensitivity output voltage signal and then outputs the signals to the control unit, and the control unit outputs the value of the current to be measured.
2. The ac/dc current measuring device according to claim 1, wherein the current to be measured Ip is:
wherein the content of the first and second substances,
a. b is a positive integer greater than 1, x (n) is a sensing output voltage signal of each sensing module when the square wave signal is at a high level, and y (i) is a sensing output voltage signal of each sensing module when the square wave signal is at a low level.
3. The ac/dc current measuring device according to claim 1, wherein the control module further comprises a display unit, and the display unit is connected with the control unit for displaying the value of the current to be measured.
4. The ac/dc current measuring device according to claim 1, wherein said first processing unit comprises:
the inverting input end of the first operational amplifier is connected with one output end of each sensing module, the non-inverting input end of the first operational amplifier is connected with the other output end of the sensing module, and the output end of the first operational amplifier is connected with the analog-to-digital conversion unit.
5. The ac/dc current measuring device according to claim 1, wherein said sensing module comprises:
a magnetic resistance variation unit, the resistance value of which varies with the magnetic field generated by the current to be measured;
the bridge driving unit is connected with the magnetic resistance change unit and used for providing a voltage source for the magnetic resistance change unit so as to enable the magnetic resistance change unit to generate a differential voltage signal;
one end of the square wave input unit is connected with the magnetic resistance conversion unit, and the other end of the square wave input unit is connected with the control unit and used for outputting the corresponding induction output voltage signal according to the level state of the square wave signal;
and one end of the second processing unit is connected with the magnetic resistance change unit, and the other end of the second processing unit is connected with the analog-to-digital conversion unit so as to amplify the induction output voltage signal.
6. The ac/dc current measuring device according to claim 5, wherein said magnetoresistance variation unit is an AMR magnetoresistance sensor.
7. The ac/dc current measuring device according to claim 5, wherein said second processing unit comprises:
the non-inverting input end and the inverting input end of the second operational amplifier are respectively connected with the magnetic resistance change unit;
and the non-inverting input end of the third operational amplifier is connected with the output end of the second operational amplifier, and the output end of the third operational amplifier is connected with the first processing unit and used for increasing bias voltage for the induction output voltage signal.
8. The ac/dc current measuring device according to claim 5, wherein the power supply terminal of said second operational amplifier is connected to one terminal of a digital controller, and the other terminal of said digital controller is connected to said control unit, for said control unit to set the amplification factor and chopper modulation frequency of said second operational amplifier.
9. The ac/dc current measuring device according to claim 5, wherein said bridge driving unit comprises:
and one end of the bridge driver circuit is connected with the magnetic resistance change unit, and the other end of the bridge driver circuit is connected with the temperature sensor.
10. An alternating current and direct current measurement method, comprising:
the control unit outputs a square wave signal;
the sensing modules are close to the current to be measured, the sensing modules receive the square wave signals, and each sensing module respectively outputs a plurality of corresponding sensing output voltage signals according to the high and low level states of the square wave signals;
when the square wave signal is at a high level, a plurality of corresponding induction output voltage signals are processed into positive sensitivity output voltage signals through a first processing unit;
when the square wave signal is at a low level, a plurality of corresponding induction output voltage signals are processed into negative sensitivity output voltage signals through the first processing unit;
and the first processing unit outputs the positive sensitivity output voltage signal and the negative sensitivity output voltage signal to the analog-to-digital conversion unit for processing, and finally outputs a current value to be detected.
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| CN113659831A (en) * | 2021-08-06 | 2021-11-16 | 优利德科技(中国)股份有限公司 | Low-ripple linear control device and linear control method |
Citations (33)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1144728A (en) * | 1997-07-28 | 1999-02-16 | Honda Motor Co Ltd | Disconnection position detecting device |
| CN101706526A (en) * | 2009-11-06 | 2010-05-12 | 徐先 | Measuring method and device of pulse width detection type magnetic modulation direct current |
| CN101915867A (en) * | 2010-07-27 | 2010-12-15 | 中国科学院等离子体物理研究所 | Current measuring circuit and method in varying high-intensity magnetic field environment |
| DE102009057282A1 (en) * | 2009-12-07 | 2011-06-09 | Siemens Aktiengesellschaft | Current measuring system for use in voltage source inverter for measuring current of induction motor, has resistor for determining inverter module output current from determined alternating current portion and intermediate circuit current |
| US20120248936A1 (en) * | 2011-04-01 | 2012-10-04 | Hsieh-Shen Hsieh | Passive alternating current sensor |
| CN102866283A (en) * | 2012-09-12 | 2013-01-09 | 北京东方计量测试研究所 | Superimposed large-current bias alternative-current (AC) current measuring device |
| CN103116056A (en) * | 2012-08-07 | 2013-05-22 | 中国电力科学研究院 | High-voltage direct current broadband domain corona current measurement system |
| CN103575960A (en) * | 2013-10-29 | 2014-02-12 | 河北工业大学 | Giant magnetoresistance effect current sensor |
| CN104267239A (en) * | 2014-10-11 | 2015-01-07 | 东南大学 | Current transformer for multipath bus current detection and current detection method thereof |
| CN104502673A (en) * | 2014-11-13 | 2015-04-08 | 浙江涵普电力科技有限公司 | AC-DC general current true RMS transmitter |
| CN104793044A (en) * | 2015-04-20 | 2015-07-22 | 华北电力大学 | Method and device for monitoring geomagnetically induced current of high-speed rails |
| CN105572456A (en) * | 2016-03-10 | 2016-05-11 | 河北工业大学 | AC/DC fluxgate current sensor |
| CN106646308A (en) * | 2016-10-27 | 2017-05-10 | 优利德科技(中国)有限公司 | Full-automatic calibration method and calibration device for Hall clamp meter |
| CN107607779A (en) * | 2016-07-12 | 2018-01-19 | 上海盛相电子科技有限公司 | Electric current detecting method and device based on magnetic modulation technique |
| CN107860959A (en) * | 2017-10-20 | 2018-03-30 | 宁波中车时代传感技术有限公司 | A kind of open-loop current sensor based on fluxgate chip |
| CN108020702A (en) * | 2016-10-31 | 2018-05-11 | 横河电机株式会社 | Current-flow test set |
| CN108020706A (en) * | 2018-01-03 | 2018-05-11 | 优利德科技(中国)有限公司 | A kind of current measuring device and electric current split-core type meter |
| CN108562778A (en) * | 2018-06-21 | 2018-09-21 | 深圳市航智精密电子有限公司 | A kind of open type current sensor and its control method |
| CN108732404A (en) * | 2017-04-24 | 2018-11-02 | 航天科工深圳（集团）有限公司 | A kind of current sensor and its more balance of flux control circuits |
| CN109212304A (en) * | 2018-11-01 | 2019-01-15 | 东北电力大学 | The detection method of digital Weak current alternating current-direct current sensor based on direct current carrier communication technology |
| CN109375118A (en) * | 2018-10-15 | 2019-02-22 | 威创集团股份有限公司 | Current measuring device and current measurement system |
| CN110007133A (en) * | 2019-04-16 | 2019-07-12 | 中国科学院上海应用物理研究所 | A kind of digital alternating current-direct current flow sensor and electric current detecting method |
| CN110161296A (en) * | 2018-03-19 | 2019-08-23 | 深圳市航智精密电子有限公司 | The excitation closed control circuit and its control method of fluxgate current sensor |
| CN209311565U (en) * | 2018-11-01 | 2019-08-27 | 东北电力大学 | Digital Weak current alternating current-direct current sensor based on direct current carrier communication technology |
| CN110609171A (en) * | 2019-10-09 | 2019-12-24 | 青岛鼎信通讯股份有限公司 | Complex residual current detection method based on magnetic core working state switching |
| CN110672913A (en) * | 2019-10-09 | 2020-01-10 | 青岛鼎信通讯股份有限公司 | Complex waveform signal processing method suitable for alternating current and direct current leakage detection |
| CN110824240A (en) * | 2019-12-09 | 2020-02-21 | 深圳市航智精密电子有限公司 | Automobile-level current sensor and detection method thereof |
| CN110927428A (en) * | 2019-11-12 | 2020-03-27 | 中国船舶重工集团公司第七一九研究所 | Wide-range wide-band high-precision magnetic balance type current measuring device |
| CN211348416U (en) * | 2019-12-09 | 2020-08-25 | 深圳市航智精密电子有限公司 | Automobile-level current sensor |
| CN111650416A (en) * | 2020-06-02 | 2020-09-11 | 珠海多创科技有限公司 | Closed-loop AC/DC current sensor |
| CN111721983A (en) * | 2020-06-23 | 2020-09-29 | 广东电网有限责任公司 | Current measurement clamp meter |
| CN112345966A (en) * | 2019-08-07 | 2021-02-09 | 青岛鼎信通讯股份有限公司 | Method and device for detecting direct current leakage through residual current transformer |
| CN215180471U (en) * | 2021-03-10 | 2021-12-14 | 优利德科技(中国)股份有限公司 | AC/DC current measuring device |
-
2021
- 2021-03-10 CN CN202110258892.5A patent/CN113049868A/en active Pending
Patent Citations (35)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1144728A (en) * | 1997-07-28 | 1999-02-16 | Honda Motor Co Ltd | Disconnection position detecting device |
| CN101706526A (en) * | 2009-11-06 | 2010-05-12 | 徐先 | Measuring method and device of pulse width detection type magnetic modulation direct current |
| DE102009057282A1 (en) * | 2009-12-07 | 2011-06-09 | Siemens Aktiengesellschaft | Current measuring system for use in voltage source inverter for measuring current of induction motor, has resistor for determining inverter module output current from determined alternating current portion and intermediate circuit current |
| CN102095918A (en) * | 2009-12-07 | 2011-06-15 | 西门子公司 | Measuring system and method for drive current of AC motor |
| CN101915867A (en) * | 2010-07-27 | 2010-12-15 | 中国科学院等离子体物理研究所 | Current measuring circuit and method in varying high-intensity magnetic field environment |
| US20120248936A1 (en) * | 2011-04-01 | 2012-10-04 | Hsieh-Shen Hsieh | Passive alternating current sensor |
| CN102735900A (en) * | 2011-04-01 | 2012-10-17 | 台达电子工业股份有限公司 | Passive alternating current sensor |
| CN103116056A (en) * | 2012-08-07 | 2013-05-22 | 中国电力科学研究院 | High-voltage direct current broadband domain corona current measurement system |
| CN102866283A (en) * | 2012-09-12 | 2013-01-09 | 北京东方计量测试研究所 | Superimposed large-current bias alternative-current (AC) current measuring device |
| CN103575960A (en) * | 2013-10-29 | 2014-02-12 | 河北工业大学 | Giant magnetoresistance effect current sensor |
| CN104267239A (en) * | 2014-10-11 | 2015-01-07 | 东南大学 | Current transformer for multipath bus current detection and current detection method thereof |
| CN104502673A (en) * | 2014-11-13 | 2015-04-08 | 浙江涵普电力科技有限公司 | AC-DC general current true RMS transmitter |
| CN104793044A (en) * | 2015-04-20 | 2015-07-22 | 华北电力大学 | Method and device for monitoring geomagnetically induced current of high-speed rails |
| CN105572456A (en) * | 2016-03-10 | 2016-05-11 | 河北工业大学 | AC/DC fluxgate current sensor |
| CN107607779A (en) * | 2016-07-12 | 2018-01-19 | 上海盛相电子科技有限公司 | Electric current detecting method and device based on magnetic modulation technique |
| CN106646308A (en) * | 2016-10-27 | 2017-05-10 | 优利德科技(中国)有限公司 | Full-automatic calibration method and calibration device for Hall clamp meter |
| CN108020702A (en) * | 2016-10-31 | 2018-05-11 | 横河电机株式会社 | Current-flow test set |
| CN108732404A (en) * | 2017-04-24 | 2018-11-02 | 航天科工深圳（集团）有限公司 | A kind of current sensor and its more balance of flux control circuits |
| CN107860959A (en) * | 2017-10-20 | 2018-03-30 | 宁波中车时代传感技术有限公司 | A kind of open-loop current sensor based on fluxgate chip |
| CN108020706A (en) * | 2018-01-03 | 2018-05-11 | 优利德科技(中国)有限公司 | A kind of current measuring device and electric current split-core type meter |
| CN110161296A (en) * | 2018-03-19 | 2019-08-23 | 深圳市航智精密电子有限公司 | The excitation closed control circuit and its control method of fluxgate current sensor |
| CN108562778A (en) * | 2018-06-21 | 2018-09-21 | 深圳市航智精密电子有限公司 | A kind of open type current sensor and its control method |
| CN109375118A (en) * | 2018-10-15 | 2019-02-22 | 威创集团股份有限公司 | Current measuring device and current measurement system |
| CN109212304A (en) * | 2018-11-01 | 2019-01-15 | 东北电力大学 | The detection method of digital Weak current alternating current-direct current sensor based on direct current carrier communication technology |
| CN209311565U (en) * | 2018-11-01 | 2019-08-27 | 东北电力大学 | Digital Weak current alternating current-direct current sensor based on direct current carrier communication technology |
| CN110007133A (en) * | 2019-04-16 | 2019-07-12 | 中国科学院上海应用物理研究所 | A kind of digital alternating current-direct current flow sensor and electric current detecting method |
| CN112345966A (en) * | 2019-08-07 | 2021-02-09 | 青岛鼎信通讯股份有限公司 | Method and device for detecting direct current leakage through residual current transformer |
| CN110672913A (en) * | 2019-10-09 | 2020-01-10 | 青岛鼎信通讯股份有限公司 | Complex waveform signal processing method suitable for alternating current and direct current leakage detection |
| CN110609171A (en) * | 2019-10-09 | 2019-12-24 | 青岛鼎信通讯股份有限公司 | Complex residual current detection method based on magnetic core working state switching |
| CN110927428A (en) * | 2019-11-12 | 2020-03-27 | 中国船舶重工集团公司第七一九研究所 | Wide-range wide-band high-precision magnetic balance type current measuring device |
| CN110824240A (en) * | 2019-12-09 | 2020-02-21 | 深圳市航智精密电子有限公司 | Automobile-level current sensor and detection method thereof |
| CN211348416U (en) * | 2019-12-09 | 2020-08-25 | 深圳市航智精密电子有限公司 | Automobile-level current sensor |
| CN111650416A (en) * | 2020-06-02 | 2020-09-11 | 珠海多创科技有限公司 | Closed-loop AC/DC current sensor |
| CN111721983A (en) * | 2020-06-23 | 2020-09-29 | 广东电网有限责任公司 | Current measurement clamp meter |
| CN215180471U (en) * | 2021-03-10 | 2021-12-14 | 优利德科技(中国)股份有限公司 | AC/DC current measuring device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113659831A (en) * | 2021-08-06 | 2021-11-16 | 优利德科技(中国)股份有限公司 | Low-ripple linear control device and linear control method |
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