CN107271935A - A kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus and method - Google Patents
A kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus and method Download PDFInfo
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- CN107271935A CN107271935A CN201710513460.8A CN201710513460A CN107271935A CN 107271935 A CN107271935 A CN 107271935A CN 201710513460 A CN201710513460 A CN 201710513460A CN 107271935 A CN107271935 A CN 107271935A
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- magnetic field
- microprocessor
- control
- field intensity
- signal
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/10—Plotting field distribution ; Measuring field distribution
Abstract
The invention discloses a kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus and method, the device includes coil mounting groove, connector and signal transacting printed circuit board (PCB), induction coil is arranged in coil mounting groove, and signal transacting printed circuit board (PCB) is connected by connector with coil mounting groove.Signal transacting printed circuit board (PCB) includes adaptive damping resonant network, input buffer stage, peak detection circuit, controllable gain amplifying circuit, sampling holder, ADC change-over circuits, microprocessor and single-pole double-throw switch (SPDT).Damping state of the invention by adjusting adaptive damping resonant network, find resonance peak, sensor is set to be maintained at space magnetic field under Critical Coupling state, so as to realize magnetic-field measurement, reduce existing sensor influences under close coupling state on space magnetic field to be measured or neighbouring Magnetic Sensor, and makes up the deficiency of the Magnetic Sensor poor sensitivity under weak coupling.
Description
Technical field
The invention belongs to magnetic field measurement technology field, a kind of more particularly to magnetic resonance coupling spatial high-frequency magnetic field intensity is surveyed
Measure apparatus and method.
Background technology
Current substantially any technical field all be unable to do without magnetic-field measurement.By taking wireless power transmission technology as an example, all it is primarily now
The transmission channel of energy is used as by the use of magnetic field.Magnetic resonance coupling wireless power transmission technology realizes electricity using HF magnetic resonance coupling
Efficiently it can transmit over long distances, the Mutual Inductance Coupling coefficient between dispatch coil directly affects the transmission range and efficiency of system.Space
Synchronously detection is the most straightforward approach of accurate analysis Mutual Inductance Coupling coefficient to magnetic field intensity, therefore designs a suitable space height
The sensor of frequency magnetic field intensity measurement is significant.
Although the method for measurement magnetic field intensity is many now, how few patents detect high frequency magnetic with paper
.For example《Multiple spot magnetic field intensity measuring instrument》(publication number：CN203759229U 3 directions) are realized based on Hall sensor
Magnetic field intensity is measured, but Hall sensor highest measurement frequency is only 1MHz, therefore can not realize the detection of high frequency magnetic field.
《A kind of digital signal locking type spatial magnetic field detecting system》(publication number：CN102495380A) although real based on electromagnetic induction method
Show the digitized measurement of magnetic field signal, but be applied to space magnetic field measurement, do not solve influencing each other between multiple sensors,
And sensor is to the influence problem in space magnetic field to be measured.
The content of the invention
In order to solve the technical problem that above-mentioned background technology is proposed, the present invention is intended to provide a kind of magnetic resonance coupling space is high
Frequency magnetic field intensity measurement apparatus and method, realize spatial high-frequency magnetic-field measurement, reduce existing sensor and are passed under close coupling state
Influence of the sensor to space magnetic field to be measured or neighbouring Magnetic Sensor, and make up the low deficiency of Magnetic Sensor sensitivity under weak coupling.
In order to realize above-mentioned technical purpose, the technical scheme is that：
A kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus, including at coil mounting groove, connector and signal
Printed circuit board (PCB) is managed, induction coil is arranged in coil mounting groove, signal transacting printed circuit board (PCB) is pacified by connector and coil
Tankage is connected；The signal transacting printed circuit board (PCB) include adaptive damping resonant network, input buffer stage, peak detection circuit,
Controllable gain amplifying circuit, sampling holder, ADC change-over circuits, microprocessor and single-pole double-throw switch (SPDT), adaptive damping resonance
The input connection induction coil of network, the input of the output end connection input buffer stage of adaptive damping resonant network, input
The input and the input of controllable gain amplifying circuit of the output end connection peak detection circuit of buffer stage, controllable gain amplification
The output end of circuit connects the input of sampling holder, and the output end of sampling holder connects the input of ADC change-over circuits,
The output end of ADC change-over circuits connects the input of microprocessor, and the moved end of single-pole double-throw switch (SPDT) connects the control of sampling holder
End processed, two of single-pole double-throw switch (SPDT) not moved end connect microprocessor and external control signal, adaptive damping resonant network respectively
Control end, the control end of controllable gain amplifying circuit, the control end of ADC change-over circuits and peak detection circuit connect micro- respectively
Processor.
Preferred scheme based on above-mentioned technical proposal, signal transacting printed circuit board (PCB) is hung down by connector and coil mounting groove
It is direct-connected to connect.
Preferred scheme based on above-mentioned technical proposal, the adaptive damping resonant network includes resonant capacitance and potentiometer,
Resonant capacitance, potentiometer and induction coil are parallel with one another, the control end connection microprocessor of potentiometer, so that controlling potential device connects
Enter the resistance of circuit.
Preferred scheme based on above-mentioned technical proposal, the input buffer stage uses OPA842 chips.
Preferred scheme based on above-mentioned technical proposal, the controllable gain amplifying circuit by two panels AD603 chip cascades and
Into.
Preferred scheme based on above-mentioned technical proposal, the sampling holder uses OPA615 chips.
Preferred scheme based on above-mentioned technical proposal, the peak detection circuit uses AD8307 chips.
High frequency magnetic field strength measurement method based on said apparatus, comprises the following steps：
(1) microprocessor controls the parameter of adaptive damping resonant network, its damping is monotonically changed；
(2) microprocessor control peak detection circuit, ginseng when finding output voltage peak value corresponding to adaptive damping network
Number, keeps the parameter value, into next step；
(3) multiple of amplification or the decay of microprocessor control controllable gain amplifying circuit, induction coil is exported
Voltage signal nurses one's health into the electric signal in the range ability of ADC change-over circuits；
(4) when need measurement magnetic field intensity when, microprocessor control single-pole double-throw switch (SPDT) state, selection microprocessor or
Person's external signal control sampling holder is in hold mode；
(5) voltage signal that the collection of microprocessor control ADC change-over circuits is held up；
(6) after the completion of AD conversion, microprocessor or external signal control sampling holder be in following state, continue with
Track high frequency magnetic field signal；
(7) microprocessor calculates the numerical value of magnetic induction intensity by the result of AD conversion and is stored in microprocessor internal,
Realize the digitlization of magnetic field signal.
The beneficial effect brought using above-mentioned technical proposal：
Pass through apparatus and method of the present invention, it is possible to achieve the accurate measurement of distribution of space magnetic field.The present invention can be solved
Influencing each other between certainly multiple sensors, and sensor is to the influence problem in space magnetic field to be measured.Moreover, the present invention can subtract
While the adverse effect of small sensor, measurement sensitivity is improved to greatest extent, so as to reduce to hardware detecting circuit
The requirement of speed.Meanwhile, the present invention digitizes the magnetic field signal detected, is easy to long-distance transmissions.In addition, present invention side
Just the synchronous network of multiple digitlization magnetic field sensors, easily realizes the synchronous acquisition in space multiple spot magnetic field.
Brief description of the drawings
Fig. 1 is the structure drawing of device of the present invention；
Label declaration：A- coil turn mounting grooves, B- attachment means, C- signal processing circuit printed boards, C1- adaptive dampings are humorous
Vibrating network, C2- input buffer stages, C3- controllable gain amplifying circuits, C4- sampling holders, C5-ADC change-over circuits, the micro- places of C6-
Manage device, C7- single-pole double-throw switch (SPDT)s, C8- peak detection circuits
The signal that Fig. 2 is the present invention flows to schematic diagram；
Fig. 3 is adaptive damping resonant network resistance figure；
Fig. 4 is input buffer stage circuit diagram；
Fig. 5 is controllable gain amplification circuit diagram；
Fig. 6 is sampling holder circuit diagram.
Embodiment
Below with reference to accompanying drawing, technical scheme is described in detail.
As shown in figure 1, a kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus, including coil mounting groove A, connection
Part B and signal processing circuit printed board C, induction coil is arranged in A circular groove.In this example, induction coil is used
Coaxial wire coiling, in order to take into account frequency band and the sensitivity of induction coil, is set to 1 circle, coil by the number of turn of induction coil
Radius is 2.5cm, and winding wire radius is 0.4mm, coil inductance 100nH.Above-mentioned C is vertically connected by connector B and A, i.e.,
Signal processing circuit printed board C is vertical with plane residing for induction coil, and the magnetic field produced by such C is vertical with tested magnetic field, from
And reduce the interference to being tested magnetic field.
As shown in Fig. 2 signal processing circuit printed board C be integrated with adaptive damping resonant network C1, input buffer stage C2, can
Control gain amplifying circuit C3, sampling holder C4, ADC change-over circuit C5 microprocessor C6, single-pole double-throw switch (SPDT) C7 and peak value inspection
Slowdown monitoring circuit C8.The C1 is connected with C2, and C2 is connected with C3, and C2 is connected with C8, and C3 is connected with C4, and C4 is connected with C5, C5 and C6 phases
Even.The gain control pipe pin of the controllable gain amplifying circuit C3 is connected with microprocessor C6.Adaptive damping resonant network C1's
Input connects induction coil, and adaptive damping resonant network C1 output end connection input buffer stage C2 input, input is slow
Rush level C2 output end connection peak detection circuit C8 input and controllable gain amplifying circuit C3 input, controllable gain
Amplifying circuit C3 output end connection sampling holder C4 input, sampling holder C4 output end connection ADC conversion electricity
Road C5 input, ADC change-over circuits C5 output end connection microprocessor C6 input, single-pole double-throw switch (SPDT) C7 moved end
Sampling holder C4 control end is connected, moved end does not connect microprocessor C6 to two of single-pole double-throw switch (SPDT) C7 respectively and outside is controlled
Signal processed, adaptive damping resonant network C1 control end, controllable gain amplifying circuit C3 control end, ADC change-over circuits C5
Control end and peak detection circuit C8 connect microprocessor C6 respectively.
In the present embodiment, adaptive damping resonant network C1 is as shown in figure 3, wherein, L is induction coil, CrFor resonance electricity
Hold, capacity is 25pF, RwIt is tunable digital potentiometer X9C102.
In the present embodiment, microprocessor C6 ADC built in single-chip microcomputer IAP15F2K61S2.Peak detection circuit C8
It is made up of logarithmic detector circuit AD8307.
In the present embodiment, as shown in figure 4, building input buffer stage based on OPA842 circuits, its gain bandwidth product is
200MHz, meets the requirement of impedance matching.As shown in figure 5, controllable gain amplifying circuit C3 is two based on AD603 circuit designs
Level programmable amplifier, gain ranging is -10dB~30dB, a width of 60MHz of two-stage band.
In the present embodiment, sampling holder C4 control pin is connected with single-pole double-throw switch (SPDT) C7, can select micro- place
Manage device C6 control samplings to keep, synchronous acquisition can also be realized by external signal control.As shown in fig. 6, in the present embodiment, adopting
Sample retainer is built based on OPA615 chips, and its frequency band is more than 700MHz.Single-pole double-throw switch (SPDT) SW selects MAX4544.
Induction coil is acted on adaptive damping resonant network, is converted into after tested high frequency magnetic field signal is passed through into induction coil
Adaptive damping resonant network resonant capacitance CrOn high-frequency voltage signal.Resonant network C1 is in parallel by LC in this example, resonance electricity
Hold Cr, the damping regulation of resonant network is by adjustable digital potentiometer RwRealize.The voltage signal of induction coil output passes through input
Buffer stage C2 inputs controllable gain amplifying circuit C3 and peak detection circuit C8.
High frequency magnetic field strength measurement method based on said apparatus, comprises the following steps：
Step 1：Microprocessor C6 control adaptive damping resonant networks C1 parameter, makes its damping be monotonically changed；
Step 2：Microprocessor C6 controls peak detection circuit C8, and adaptive damping network institute is right when finding output voltage peak value
The parameter answered, keeps the parameter value, into next step；
Step 3：The multiple of microprocessor C6 control controllable gain amplifying circuits C3 amplification or decay, by induction coil
The voltage signal of output nurses one's health into the electric signal in ADC change-over circuits C5 range ability；
Step 4：When needing measurement magnetic field intensity, microprocessor C6 control single-pole double-throw switch (SPDT)s C7 state is selected micro-
Processor C6 or external signal control sampling holder C4 are in hold mode；
Step 5：The voltage signal that microprocessor C6 control ADC change-over circuits C5 collections are held up；
Step 6：After the completion of AD conversion, microprocessor C6 or external signal control sampling holder C4 are in and follow shape
State, continues to track high frequency magnetic field signal；
Step 7：Microprocessor calculates the numerical value of magnetic induction intensity by the result of AD conversion and is stored in microprocessor C6
Inside, realizes the digitlization of magnetic field signal.
Although it should be pointed out that specifically show and describe the present invention with reference to preferred embodiment, implementation described above
Content, is one kind with reference to specific preferred embodiment, is further description made for the present invention, it is impossible to assert this
The specific implementation of invention be confined to these explanation, it is required that meet it is consistent with thinking disclosed herein and principle most
The coiling of wide scope, such as induction coil, design of adaptive damping resonant network etc..For the general of the technical field of the invention
For logical technical staff, on the premise of present inventive concept and method is not departed from, some simple modifications or replacement can also be made.
In the concept of the invention that attached claims are limited, protection scope of the present invention should be all considered as belonging to.
Claims (8)
1. a kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus, it is characterised in that：Including coil mounting groove (A), even
Fitting (B) and signal transacting printed circuit board (PCB) (C), induction coil are arranged in coil mounting groove (A), signal transacting printed circuit
Plate (C) is connected by connector (B) with coil mounting groove (A)；It is humorous that the signal transacting printed circuit board (PCB) (C) includes adaptive damping
Vibrating network (C1), input buffer stage (C2), peak detection circuit (C8), controllable gain amplifying circuit (C3), sampling holder
(C4), ADC change-over circuits (C5), microprocessor (C6) and single-pole double-throw switch (SPDT) (C7), adaptive damping resonant network (C1)
Input connects induction coil, and the input of the output end connection input buffer stage (C2) of adaptive damping resonant network (C1) is defeated
Enter the input of the input and controllable gain amplifying circuit (C3) of the output end connection peak detection circuit (C8) of buffer stage (C2)
End, controllable gain amplifying circuit (C3) output end connection sampling holder (C4) input, sampling holder (C4) it is defeated
Go out the input of end connection ADC change-over circuits (C5), the input of the output end connection microprocessor (C6) of ADC change-over circuits (C5)
End, the control end of the moved end connection sampling holder (C4) of single-pole double-throw switch (SPDT) (C7), two of single-pole double-throw switch (SPDT) (C7) are not
Moved end connects microprocessor (C6) and external control signal, the control end of adaptive damping resonant network (C1), controllable gain respectively
Control end, the control end of ADC change-over circuits (C5) and the peak detection circuit (C8) of amplifying circuit (C3) connect microprocessor respectively
Device (C6).
2. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：Signal transacting
Printed circuit board (PCB) (C) is connected by the way that connector (B) is vertical with coil mounting groove (A).
3. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：It is described variable
Damped harmonic oscillation network (C1) includes resonant capacitance and potentiometer, and resonant capacitance, potentiometer and induction coil are parallel with one another, potentiometer
Control end connection microprocessor (C6) so that controlling potential device access circuit resistance.
4. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：The input
Buffer stage (C2) uses OPA842 chips.
5. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：It is described controllable
Gain amplifying circuit (C3) is formed by two panels AD603 chip cascades.
6. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：The sampling
Retainer (C4) uses OPA615 chips.
7. magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus according to claim 1, it is characterised in that：The peak value
Detect that circuit (C8) uses AD8307 chips.
8. the high frequency magnetic field strength measurement method based on claim 1 described device, it is characterised in that comprise the following steps：
(1) parameter of microprocessor (C6) control adaptive damping resonant network (C1), makes its damping be monotonically changed；
(2) microprocessor (C6) control peak detection circuit (C8), when finding output voltage peak value corresponding to adaptive damping network
Parameter, the parameter value is kept, into next step；
(3) multiple of amplification or the decay of microprocessor (C6) control controllable gain amplifying circuit (C3), defeated by induction coil
The voltage signal gone out nurses one's health into the electric signal in ADC change-over circuits (C5) range ability；
(4) when needing measurement magnetic field intensity, the state of microprocessor (C6) control single-pole double-throw switch (SPDT) (C7) selects microprocessor
Device (C6) or external signal control sampling holder (C4) are in hold mode；
(5) voltage signal that microprocessor (C6) control ADC change-over circuits (C5) collection is held up；
(6) after the completion of AD conversion, microprocessor (C6) or external signal control sampling holder (C4) are in following state, after
Continuous tracking high frequency magnetic field signal；
(7) microprocessor calculates the numerical value of magnetic induction intensity by the result of AD conversion and is stored in microprocessor (C6) inside,
Realize the digitlization of magnetic field signal.
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| CN201710513460.8A CN107271935A (en) | 2017-06-29 | 2017-06-29 | A kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus and method |
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| CN201710513460.8A CN107271935A (en) | 2017-06-29 | 2017-06-29 | A kind of magnetic resonance coupling spatial high-frequency magnetic field intensity measurement apparatus and method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113687275A (en) * | 2021-08-26 | 2021-11-23 | 南京工业大学 | Magnetic field self-display device of wireless power transmission system based on magnetic structure factor |
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