CN109030907A - A kind of current probe and its control method - Google Patents

A kind of current probe and its control method Download PDF

Info

Publication number
CN109030907A
CN109030907A CN201710436006.7A CN201710436006A CN109030907A CN 109030907 A CN109030907 A CN 109030907A CN 201710436006 A CN201710436006 A CN 201710436006A CN 109030907 A CN109030907 A CN 109030907A
Authority
CN
China
Prior art keywords
circuit
resistance
connecting pin
current probe
capacitor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201710436006.7A
Other languages
Chinese (zh)
Other versions
CN109030907B (en
Inventor
张宁强
王悦
王铁军
李维森
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Rigol Technologies Inc
Original Assignee
Beijing Rigol Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Rigol Technologies Inc filed Critical Beijing Rigol Technologies Inc
Priority to CN201710436006.7A priority Critical patent/CN109030907B/en
Publication of CN109030907A publication Critical patent/CN109030907A/en
Application granted granted Critical
Publication of CN109030907B publication Critical patent/CN109030907B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/0092—Measuring current only
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
    • G01R1/30—Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
    • 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
    • G01R15/202—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 Hall-effect devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
    • G01R35/005—Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Current Or Voltage (AREA)

Abstract

The present invention provides a kind of current probe and its control methods, are related to current measurement techniques field.It can control feedback system circuit by control unit circuit, carry out the automatic frequency response calibration of current probe；By control unit circuit control demagnetization signal generating circuit, current probe demagnetization control is carried out；By control unit circuit control direct current calibration signal generation circuit, the direct current offset for carrying out current probe is adjusted；By control unit circuit control filter circuit, the bandwidth control of current probe is carried out；By control unit circuit control output impedance match circuit, the DC precision for carrying out current probe is adjusted.The present invention can solve the detection of each performance indicator after the completion of production of current probe and calibration process has very complicated.

Description

A kind of current probe and its control method
Technical field
The present invention relates to current measurement techniques field more particularly to a kind of current probe and its control methods.
Background technique
Currently, with the development of electronic technology, the application of current probe is very extensive.The basic principle of current probe It is to flow through the electric current of conducting wire to generate magnetic field around its conducting wire, magnetic field is received by sensor, converts linear electricity Pressure amount.The linear voltage amount can be shown and be measured on oscillograph or other measuring instruments, to reach in conducting wire The purpose that measures of electric current.It can be widely applied to survey by way of carrying out current in wire measurement current probe at present Measure motor driving, Switching Power Supply, power inverter/converter, LCD display (Liquid Crystal Display, liquid crystal Show device), electric ballast, the stable state of amplifier or transient current, transportation system, mobile communication, industry/consumer electronics produce Product and semiconductor equipment etc..
The simple principle block diagram of the current probe of the prior art is as shown in Figure 1.The current probe of the prior art, which uses, to be become Depressor principle and Hall effect principle can be measured by the current probe down toward DC (direct current, Direct Current) Low-frequency current signal, and up to high-frequency current signal.The current probe forms closure by upper magnetic core 101 and lower magnetic core 102 Magnetic core 103.The current probe further includes the Hall sensor 105 being clipped on lower 102 section of magnetic core, additionally includes signal amplification Device 106, single-pole double-throw switch (SPDT) 112, power amplifier 111, feedback system 103, the coil 107 being wound on lower magnetic core 103, termination Resistance 109 and signal output stage operational amplifier 108.105 1 biased electricals of Hall sensor are given by system power supply 110 Pressure, to add magnetic flux to 105 sensing part of Hall sensor, Hall sensor 105 is exportable linearly related with it Hall voltage parameter.Signal amplifier 106 acquires the Hall voltage parameter that Hall sensor 105 exports.And pass through single-pole double throw The signal that signal amplifier 106 exports is coupled in power amplifier 111 by switch 112, the magnetic head demagnetization signal of current probe And be coupled in power amplifier 111 by single-pole double-throw switch (SPDT) 112, it is passed after being amplified signal by power amplifier 111 It is defeated to arrive coil 107, the secondary windings for the transformer that coil 107 is formed as closed magnetic core 103, and armature winding is exactly tested leads Line 104.Another termination terminating resistor 109 of coil 107, while output stage operational amplifier 108 is connect, as output stage.Due to 104 surrounding of measured conductor can generate magnetic field, and magnetic flux can be strapped in magnetic core by the closed magnetic core 103 of high magnetic permeability.When magnetic flux hangs down When direct puncture crosses the Hall sensor 105 being embedded in magnetic core, Hall sensor 105 can export Hall voltage parameter, Hall electricity Pressure parameter is inputed to signal amplifier 106 in the form of difference, then is communicated to power amplifier by single-pole double-throw switch (SPDT) 112 111.The switch 112 of single-pole double throw also can choose demagnetization signal and be input to power amplifier 111.Feedback system 113 is generally adopted It is fed back with conventional, electric-resistance, to achieve the purpose that adjust gain stabilization system.Power amplifier 111 linearly puts Hall voltage parameter The greatly magnitude of current, secondary coil of the driving coil 107 as transformer.The flow direction and be tested that the electric current generates in coil Flow direction that conducting wire generates in coil is contrary on the contrary, both magnetic fluxs are equal in magnitude in magnetic core, cancels out each other, The electric current that the electric current in measured conductor and power amplifier 111 export at this time has certain linear relationship, power amplifier 111 The magnitude of current of output is output in oscillograph or measuring instrument by output stage operational amplifier 108.It is put by measuring power The electric current that big device 111 exports measures the electric current flowed through in measured wire, is exactly the principle of current probe Zero flux measurement.
During carrying out the above-mentioned prior art, inventor is had found during Reusability current probe, closure The magnetic head of magnetic core 103 is easy to produce remanent magnetism, this will introduce additional error to the measurement of current probe, so that measurement result produces Raw deviation.For a user in order to make above-mentioned current probe carry out demagnetization, need to proceed as follows, it is necessary first to by current-carrying Conductor 104 is shifted out from the closure magnetic head 103 of current probe, and then current probe circuit passes through control single-pole double-throw switch (SPDT) 112, the signal that will enter into power amplifier 111 switches to demagnetization signal, carries out demagnetization to closed magnetic core 103.Therefore, hilted broadsword In this process, will seem commutator 112 key especially.Due to the frequent switching of single-pole double-throw switch (SPDT) 112, it is easy It damages, to affect the demagnetization performance to closed magnetic core 103.In addition, due to the bias voltage of Hall sensor 105 itself Asymmetry, can also have signal output in the case where no measured conductor.It is so also to bring one to current probe measurement A DC offset error.The prior art is to handle the DC offset error by adjusting the bias voltage of Hall sensor to realize 's.However this bearing calibration sensitivity requirement is higher, the phenomenon that being easy to appear repeatedly in adjustment process, always zero point or so very Hardly possible, which is adjusted, arrives zero point.In addition, the current probe being completed needs to carry out the inspection of a series of performance indicator in plant produced It surveys and calibrates.The index wherein detected has: the detection and calibration of the DC precision of current probe, the detection and control of bandwidth It makes, detection and calibration of the Frequency Response in frequency range etc..And the detection of DC precision and calibration are by output end Fixed resistance is realized.The Detection & Controling of bandwidth are realized by filter.The inspection of Frequency Response in bandwidth range It surveys and calibrate, is realized by the feed circuit of regulation power amplifier.These detections and calibration are all by artificial It measures and calibrates manually, seriously affected the efficiency of production.As it can be seen that there are in structure for the current probe of the prior art Defect be easy to cause the problem of the measurement inaccuracy of current probe, while each performance after the completion of production of current probe refers to There is very complicated in target detection and calibration process.
Summary of the invention
The embodiment of the present invention provides a kind of current probe and its control method, is deposited with solving the current probe of the prior art Defect in structure, be easy to cause current probe measurement inaccuracy problem, while current probe after the completion of production Each performance indicator detection and calibration process there are problems that very complicated.
In order to achieve the above objectives, the present invention adopts the following technical scheme:
A kind of current probe, including be made of upper magnetic core and lower magnetic core closed magnetic core, Hall sensor, difference amplifier Circuit, operation amplifier circuit, feedback system circuit, the first parallel end connection resistance, signal output apparatus and control unit circuit；
The Hall sensor is embedded in one side of the lower magnetic core, and wears in the magnetic head of the lower magnetic core and upper magnetic core composition Measured wire is crossed；Two output ends of the Hall sensor are separately connected the non-inverting input terminal of differential amplifier circuit and anti- Phase input terminal；The output end of the differential amplifier circuit is connected to the inverting input terminal of the operation amplifier circuit；It is described Feedback system circuit connection is between the inverting input terminal and output end of the operation amplifier circuit；The lower magnetic core be wound with by The opposite side for surveying one side of conducting wire is wound with secondary winding coil, and one end of the secondary winding coil connects the operational amplifier electricity The output end on road, the other end of the secondary winding coil connect one end and the signal output electricity of the first parallel end connection resistance Road；The other end of the first parallel end connection resistance is grounded；
Feedback system circuit described in described control unit circuit connection, to carry out the automatic frequency response calibration of current probe.
Further, the current probe further includes power amplifier circuit and direct current calibration signal generation circuit；It is described The inverting input terminal of power amplifier circuit is connect with the output end of the operation amplifier circuit, the power amplifier circuit Output end connect with one end of the secondary winding coil；The direct current calibration signal generation circuit and the power amplifier The non-inverting input terminal of circuit or the non-inverting input terminal connection of operation amplifier circuit；
Described control unit circuit is also connected with the direct current calibration signal generation circuit, inclined with the direct current for carrying out current probe Transposition section.
Further, the current probe further includes demagnetization signal generating circuit；The demagnetization signal generating circuit and institute State the non-inverting input terminal of power amplifier circuit or the non-inverting input terminal connection of operation amplifier circuit；
Described control unit circuit is also connected with the demagnetization signal generating circuit, to carry out current probe demagnetization control.
Specifically, the signal output apparatus includes an output stage operation amplifier circuit；The secondary winding coil The other end connects one end of the first parallel end connection resistance and the input terminal of the output stage operation amplifier circuit；It is described defeated Measurement output end of the output end of grade operation amplifier circuit as the current probe out.
Specifically, the Hall sensor has first input end, the second input terminal, the first output end and the second output End；The first input end and the second input terminal connect the power supply output end of the system power supply circuit；
First output end connects the non-inverting input terminal of the differential amplifier circuit, and the second output terminal connects institute State the inverting input terminal of differential amplifier circuit；The output end of the differential amplifier circuit and the operation amplifier circuit RC filter circuit is additionally provided between inverting input terminal；The output end of the differential amplifier circuit connects the defeated of RC filter circuit Enter end, the inverting input terminal of the output end connection operation amplifier circuit of RC filter circuit.
Specifically, the signal output apparatus includes series termination resistance, transmission cable, filter circuit, output impedance Match circuit and high frequency connectors；
One end of the series termination resistance is connect with the other end of the secondary winding coil；The series termination resistance The other end be sequentially connected the transmission cable, filter circuit and high frequency connectors；The filter circuit and the high frequency The junction of connector connects one end of the second parallel end connection resistance, another termination of the second parallel end connection resistance Ground；The high frequency connectors with the AFE(analog front end) of oscillograph for connecting；
Described control unit circuit is also connect with the filter circuit and output impedance match circuit respectively, with respectively into The bandwidth control of row current probe and the DC precision of current probe are adjusted.
Specifically, the differential amplifier circuit includes a difference amplifier chip；The difference amplifier chip includes Inverting input terminal IN-, non-inverting input terminal IN+, first resistor connecting pin Rg1, second resistance connecting pin Rg2, positive pole connection Hold Vs+, power cathode connecting pin Vs ﹣, output end vo ut and reference voltage connecting pin REF；
First output end of the Hall sensor connects the inverting input terminal IN ﹣；The second of the Hall sensor Output end connects the non-inverting input terminal IN+；
The first resistor connecting pin Rg1 is connected with second resistance connecting pin Rg2 by a first resistor；
The positive pole connecting pin Vs+ is loaded with positive 12 volts of voltage；The power cathode connecting pin Vs ﹣ is loaded with minus 12 Lie prostrate voltage；
The reference voltage connecting pin REF ground connection；
The output end vo ut connects the input terminal of the RC filter circuit.
Specifically, the feedback system circuit includes one first digital adjustable potentiometer；Described first digital adjustable potential Device includes the first pin connecting pin A1, second pin connecting pin A2, third pin connecting pin B1, the 4th pin connecting pin B2, the Five pin connecting pin W1, the 6th pin connecting pin W2, ground terminal GND, operating voltage connecting pin VDD, bi-directional data connect line end SDA and clock connect line end SCL；
The ground terminal GND ground connection；The operating voltage connecting pin VDD is loaded with positive 5 volts of voltage；The bi-directional data connects Terminals SDA and clock connection line end SCL is exported with the bi-direction data signal of described control unit circuit respectively by I2C bus End is connected with clock signal output terminal；First pin connecting pin A1 and the 5th pin connecting pin W1 are connected；Described second Positive 12 volts of voltage is loaded with after one second resistance of pin connecting pin A2 connection；4th pin connecting pin B2 connection, the one third electricity Minus 12 volts of voltage is loaded with after resistance.
Specifically, the operation amplifier circuit include: operational amplifier, the 4th resistance, the 5th resistance, the 6th resistance with And first capacitor；
The operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The inverting input terminal of the operational amplifier is logical The 4th resistance is crossed to connect with the output end of the RC filter circuit；The non-inverting input terminal of the operational amplifier is separately connected One end of 5th resistance and one end of the 6th resistance；The other end of 5th resistance is as the operation amplifier circuit Non-inverting input terminal；The other end of 6th resistance is grounded；The output end of the operational amplifier and operational amplifier it is anti- Phase input terminal connects the both ends of the first capacitor；The output end of the operational amplifier is also connected with the described first digital adjustable electric The third pin connecting pin B1 of position device；The inverting input terminal of the operational amplifier is also connected with the described first digital adjustable potentiometer The first pin connecting pin A1.
Specifically, the power amplifier circuit include: power amplifier, the 7th resistance, the 8th resistance, the 9th resistance with And the tenth resistance；
The power amplifier is loaded with positive 12V voltage and negative 12V voltage；The inverting input terminal of the power amplifier is logical The 8th resistance is crossed to connect with the output end of the operational amplifier；The non-inverting input terminal of the power amplifier is separately connected One end of 9th resistance and one end of the tenth resistance；The other end of 9th resistance is as the power amplifier circuit Non-inverting input terminal；The other end of tenth resistance is grounded；The output end of the power amplifier and power amplifier it is anti- Phase input terminal connects the both ends of the 7th resistance；The output end of the power amplifier is also connected with the secondary winding coil One end.
Specifically, the direct current calibration signal generation circuit includes: direct current calibration operational amplifier, eleventh resistor, the 12 resistance and the second capacitor；
The direct current calibration operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The direct current calibrates operation amplifier The inverting input terminal of device is connected by the 6th pin connecting pin W2 of the eleventh resistor and the first digital adjustable potentiometer It connects；The non-inverting input terminal of the direct current calibration operational amplifier calibrates operation amplifier by the twelfth resistor and the direct current The output end of device connects；The output end of the direct current calibration operational amplifier also passes through second capacity earth；The direct current Calibrate output end of the output end of operational amplifier as the direct current calibration signal generation circuit.
Specifically, the demagnetization signal generating circuit include: demagnetization operational amplifier, thirteenth resistor, the 14th resistance, 15th resistance, the 16th resistance, third capacitor, the 4th capacitor and the 5th capacitor；
The demagnetization operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The reverse phase of the demagnetization operational amplifier Input terminal passes through the 14th resistance eutral grounding；The non-inverting input terminal of the demagnetization operational amplifier passes through the 4th capacitor and the tenth It is grounded after the parallel circuit of five resistance composition；The non-inverting input terminal of the demagnetization operational amplifier also pass through the 5th capacitor and The output end of the demagnetization operational amplifier is connected after the series circuit of 16th resistance composition；The demagnetization operational amplifier Output end is connect with the degaussing control signal output end of described control unit circuit；The output end of the demagnetization operational amplifier is also It is grounded after the parallel circuit being made up of the third capacitor and thirteenth resistor；The output end of the demagnetization operational amplifier is made For the output end of the demagnetization signal generating circuit.
Specifically, the filter circuit is 5 rank Butterworth LPF circuits；The 5 rank Butterworth low pass Filter circuit include: digital adjustable condenser, the first inductance, the second inductance, the 6th capacitor, the 7th capacitor, the 8th capacitor with And the 9th capacitor；The number adjustable condenser includes enable signal connecting pin SEN, the first ground connecting pin GND1, the second ground company Connect end GND2, third connecting pin GND3, the 4th ground connecting pin GND4, clock signal connecting pin SCLK, voltage connection VDD, First capacitor device port RF-1, the second capacitor ports RF-2, third capacitor ports RF+1, the 4th capacitor ports RF+2 and Bi-directional data connecting pin SDAT；
One end of first inductance connects the transmission cable, the other end connection of first inductance second electricity One end of sense, the other end of second inductance are connect with the output impedance match circuit；One end of 6th capacitor connects It is connected to the junction of first inductance and the transmission cable；One end of 7th capacitor is connected with one end of the 8th capacitor In the junction of first inductance and second inductance；One end of 9th capacitor is connected to second inductance and institute State the junction of output impedance match circuit；The other end of 6th capacitor, the other end of the 7th capacitor and the 9th capacitor The other end is grounded；The other end of 8th capacitor connects the third capacitor ports RF+1 and the 4th capacitor ports RF +2；The other end, the other end of the 7th capacitor and the other end of the 9th capacitor of 6th capacitor are also connected with first capacitor device end Mouth RF-1 and the second capacitor ports RF-2；
First ground connecting pin GND1, the second ground connecting pin GND2, third ground connecting pin GND3, the 4th ground connecting pin GND4 is grounded respectively；The voltage connection VDD is loaded with positive 3.3 volts of voltage；Described in the enable signal connecting pin SEN connection The enable signal output end of control unit circuit；The clock of the clock signal connecting pin SCLK connection described control unit circuit Signal output end；The bi-directional data output end of the bi-directional data connecting pin SDAT connection described control unit circuit.
Specifically, the output impedance match circuit includes the second digital adjustable potentiometer, the 17th resistance, the 18th electricity Resistance, the 19th resistance and the 20th resistance；Described second digital adjustable potentiometer includes the first pin connecting pin A1, second pin Connecting pin A2, third pin connecting pin B1, the 4th pin connecting pin B2, the 5th pin connecting pin W1, the 6th pin connecting pin W2, Ground terminal GND, operating voltage connecting pin VDD, bi-directional data connection line end SDA and clock connect line end SCL；
One end of 17th resistance, one end of the 18th resistance, one end of the 19th resistance and the 20th resistance One end is separately connected 5 rank Butterworth LPF circuits and high frequency connectors；The other end of 17th resistance, The other end of the other end of 18 resistance and the 19th resistance is grounded；The second number of other end connection of 20th resistance 4th pin connecting pin B2 of adjustable potentiometer；
Second pin connecting pin A2, the 6th pin connecting pin W2 and the ground terminal GND of described second digital adjustable potentiometer Ground connection；The operating voltage connecting pin VDD of described second digital adjustable potentiometer is loaded with positive 3.3 volts of voltage；Second number Adjustable potentiometer bi-directional data connection line end SDA and clock connection line end SCL by I2C bus respectively with described control unit The bi-direction data signal output end of circuit is connected with clock signal output terminal.
A kind of control method of current probe, applied to above-mentioned current probe；The described method includes:
By control unit circuit control feedback system circuit, the automatic frequency response calibration of current probe is carried out；
By control unit circuit control demagnetization signal generating circuit, current probe demagnetization control is carried out；
By control unit circuit control direct current calibration signal generation circuit, the direct current offset for carrying out current probe is adjusted；
By control unit circuit control filter circuit, the bandwidth control of current probe is carried out；
By control unit circuit control output impedance match circuit, the DC precision for carrying out current probe is adjusted.
Specifically, it is described by control unit circuit control feedback system circuit, carry out the automatic frequency response school of current probe It is quasi-, comprising:
It is adjustable that the first number is adjusted by the bi-direction data signal output end and clock signal output terminal of control unit circuit The resistance value of potentiometer carries out the automatic frequency response calibration of current probe.
Specifically, carrying out current probe demagnetization control, packet by control unit circuit control demagnetization signal generating circuit It includes:
Degaussing control signal is generated by the degaussing control signal output end of control unit circuit, so that third capacitor carries out Charge and discharge generate the sinusoidal signal that range value is gradually reduced in the output end of demagnetization signal generating circuit, carry out current probe and disappear Magnetic control.
Specifically, by control unit circuit control direct current calibration signal generation circuit, the direct current for carrying out current probe is inclined Transposition section, comprising:
The first digital adjustable potentiometer is adjusted by control unit circuit, changes the output of direct current calibration signal generation circuit Direct current signal, the direct current offset for carrying out current probe are adjusted.
Specifically, carrying out the bandwidth control of current probe by control unit circuit control filter circuit, comprising:
The capacitance that digital adjustable condenser is adjusted by control unit circuit control, carries out the bandwidth control of current probe System.
Specifically, carrying out the DC precision tune of current probe by control unit circuit control output impedance match circuit Section, comprising:
The resistance value that the second digital adjustable potentiometer is adjusted by control unit circuit control carries out the direct current essence of current probe Degree is adjusted.
A kind of current probe provided in an embodiment of the present invention and its control method, by exporting two of Hall sensor End is separately connected differential amplifier circuit non-inverting input terminal and inverting input terminal, and not one end ground connection of Hall sensor, separately One end connects differential amplifier circuit and avoids hall device itself due to bias voltage so that the output of Hall sensor balances Asymmetry, have in the case where no measured conductor signal output cause current probe measurement result inaccuracy problem. In addition, the present invention can control feedback system circuit by control unit circuit, the automatic frequency response calibration of current probe is carried out；Control Demagnetization signal generating circuit processed carries out current probe demagnetization control；Direct current calibration signal generation circuit is controlled, current probe is carried out Direct current offset adjust；Filter circuit is controlled, the bandwidth control of current probe is carried out；Output impedance match circuit is controlled, into The DC precision of row current probe is adjusted, to avoid detection and the school of each performance indicator after the completion of production of current probe There is very complicated in quasi- process.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this Some embodiments of invention without any creative labor, may be used also for those of ordinary skill in the art To obtain other drawings based on these drawings.
Fig. 1 is the simple principle schematic diagram of the current probe of the prior art；
Fig. 2 is a kind of structural schematic diagram one of current probe provided in an embodiment of the present invention；
Fig. 3 is a kind of structural schematic diagram two of current probe provided in an embodiment of the present invention；
Fig. 4 is a kind of structural schematic diagram three of current probe provided in an embodiment of the present invention；
Fig. 5 is the structural schematic diagram of the system power supply circuit in the embodiment of the present invention；
Fig. 6 is the schematic diagram of the Hall sensor in the embodiment of the present invention；
Fig. 7 is a kind of structural schematic diagram four of current probe provided in an embodiment of the present invention；
Fig. 8 is the schematic diagram of the differential amplifier circuit in the embodiment of the present invention；
Fig. 9 is the schematic diagram of the feedback system circuit in the embodiment of the present invention；
Figure 10 is the schematic diagram of the operation amplifier circuit in the embodiment of the present invention；
Figure 11 is the schematic diagram of the power operational amplifier circuit in the embodiment of the present invention；
Figure 12 is the schematic diagram of the direct current calibration signal generation circuit in the embodiment of the present invention；
Figure 13 is the schematic diagram of the demagnetization signal generating circuit in the embodiment of the present invention；
Figure 14 is the schematic diagram of 5 rank Butterworth filter circuits in the embodiment of the present invention；
Figure 15 is the schematic diagram of the output impedance match circuit in the embodiment of the present invention；
Figure 16 is the schematic diagram of the high frequency output terminal BNC in the embodiment of the present invention；
Figure 17 is the chip microcontroller scheme schematic diagram of the control unit circuit in the embodiment of the present invention；
Figure 18 is a kind of flow chart of the control method of current probe provided in an embodiment of the present invention.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.
As shown in Fig. 2, the embodiment of the present invention provides a kind of current probe 20, including by 202 groups of upper magnetic core 201 and lower magnetic core At closed magnetic core 203, Hall sensor 204, differential amplifier circuit 220, operation amplifier circuit 205, feedback system electricity Road 207 (being used for gain adjustment), the first parallel end connection resistance 211, signal output apparatus 212 and control unit circuit 254.
The Hall sensor 204 is embedded in one side of the lower magnetic core 202, and the lower magnetic core 202 and 201 groups of upper magnetic core At magnetic head in pass through have measured wire 213.Two output ends of the Hall sensor 204 are separately connected difference amplifier electricity The non-inverting input terminal and inverting input terminal on road 220；The output end of the differential amplifier circuit 220 is connected to operational amplifier electricity The inverting input terminal on road 205；The feedback system circuit 207 is connected to the inverting input terminal of the operation amplifier circuit 205 Between output end；The opposite side on one side that the lower magnetic core 202 is wound with measured wire 213 is wound with secondary winding coil 214, described One end of secondary winding coil 214 connects the output end of the operation amplifier circuit 205, the secondary winding coil 214 The other end connects one end and the signal output apparatus 212 of the first parallel end connection resistance 211；The first parallel end connection resistance 211 other end ground connection.
Described control unit circuit 254 connects the feedback system circuit 207, to carry out the automatic frequency response school of current probe It is quasi-.
In addition, as shown in Fig. 2, the current probe 20, further includes system power supply circuit 210, the system power supply circuit 210 It powers for each section of entire current probe 20.
Further, as shown in figure 3, the current probe 20 further includes power amplifier circuit 206 and direct current calibration letter Number generation circuit 209；The output of the inverting input terminal of the power amplifier circuit 206 and the operation amplifier circuit 205 End connection, the output end of the power amplifier circuit 206 are connect with one end of the secondary winding coil 214；The direct current The non-inverting input terminal or operation amplifier circuit 205 of calibration signal generation circuit 209 and the power amplifier circuit 206 Non-inverting input terminal connection.
Described control unit circuit 254 is also connected with the direct current calibration signal generation circuit 209, to carry out current probe Direct current offset is adjusted.
Further, as shown in figure 3, the current probe 20 further includes demagnetization signal generating circuit 208；The demagnetization letter The non-inverting input terminal of number generation circuit 208 and the power amplifier circuit 206 or operation amplifier circuit 205 it is same mutually defeated Enter end connection.In Fig. 3, only with a kind of connection side of demagnetization signal generating circuit 208 and direct current calibration signal generation circuit 209 It is illustrated for formula, details are not described herein again for other connection types.
Described control unit circuit 254 is also connected with the demagnetization signal generating circuit 208, to carry out current probe demagnetization control System.
Since closed magnetic core 203 is made of high frequency magnetic material, can be magnetized in magnetic field, the magnetic domain in closed magnetic core exists Arrangement that will be orderly under the action of external magnetic field, therefore, closed magnetic core has magnetism.Magnetic domain is still orderly after magnetic field is removed Arrangement, that is to say, that closed magnetic core still has magnetism.Closed magnetic core still maintains magnetic in the case where removing external magnetic field Property, i.e. remanent magnetism.Therefore it needs to carry out demagnetization using demagnetization signal generating circuit 208.
In this way, measured signal and demagnetization signal are overlapped, so that the function of direct demagnetization is realized, in addition by tested letter Number and direct current calibration signal be overlapped, so as to realize DC offset calibration.
Specifically, as shown in figure 4, the signal output apparatus 212 includes an output stage operation amplifier circuit 215；Institute The other end for stating secondary winding coil 214 connects one end of the first parallel end connection resistance 211 and the output stage operation is put The input terminal of big device circuit 215；Survey of the output end of the output stage operation amplifier circuit 215 as the current probe 20 Measure output end.
Specifically, the structure of the system power supply circuit 210 can be as shown in figure 5, system power supply circuit chip therein Including empty foot NC1 to NC3, input pin IN, output pin OUT, grounding pin GND, Level tune controls pin NR and electricity Pressure fine tuning pin TRIM；In addition the structure of system power supply circuit 210 further includes two amplifiers.
Specifically, as shown in fig. 6, the Hall sensor 204 has first input end 216, the second input terminal 217, the One output end 218 and second output terminal 219；The first input end 216 and the second input terminal 217 connect system power supply circuit 210 power supply output end, i.e., the output end of two amplifiers as shown in Figure 5.
Further, as shown in fig. 7, the first output end 218 of the Hall sensor 204 can connect difference amplifier electricity The second output terminal 219 of the non-inverting input terminal on road 220, the Hall sensor 204 can connect the differential amplifier circuit 220 inverting input terminal；The output end of the differential amplifier circuit 220 connects the input terminal of a RC filter circuit 221, RC filter The inverting input terminal of the output end connection operation amplifier circuit 205 of wave circuit 221.
Specifically, as shown in fig. 7, the signal output apparatus 212 include series termination resistance 222, transmission cable 223, Filter circuit 224, output impedance match circuit 225 and high frequency connectors 226.
One end of the series termination resistance 222 is connect with the other end of the secondary winding coil 214；The series connection end The other end of connecting resistance 222 is sequentially connected the transmission cable 223, filter circuit 224 and high frequency connectors 226；The filter Wave device circuit 224 connect resistance one end of the output impedance match circuit 225 with the junction of the high frequency connectors 226, The resistance other end of the output impedance match circuit 225 is grounded；The high frequency connectors 226 are for the simulation with oscillograph 30 Front end 301 connects.
Described control unit circuit 254 also connects with the filter circuit 224 and output impedance match circuit 225 respectively It connects, to carry out the bandwidth control of current probe and the DC precision adjusting of current probe respectively.
Specifically, as shown in figure 8, the differential amplifier circuit 220 includes a difference amplifier chip 227；The difference Dividing amplifier chip includes inverting input terminal IN-, non-inverting input terminal IN+, first resistor connecting pin Rg1, second resistance connecting pin Rg2, positive pole connecting pin Vs+, power cathode connecting pin Vs ﹣, output end vo ut and reference voltage connecting pin REF.
The inverting input terminal IN ﹣ in 218 connection figure 8 of the first output end of Hall sensor 204 described in Fig. 6； The non-inverting input terminal IN+ in 219 connection figure 8 of second output terminal of the Hall sensor 204.
As shown in figure 8, the first resistor connecting pin Rg1 and second resistance connecting pin Rg2 is connected by a first resistor 228 It connects.
The positive pole connecting pin Vs+ is loaded with positive 12 volts of voltage；The power cathode connecting pin Vs ﹣ is loaded with minus 12 Lie prostrate voltage.
The reference voltage connecting pin REF ground connection.
The output end vo ut of the difference amplifier chip 227 connects the input terminal of the RC filter circuit 221.
Herein, since the signal of Hall sensor output is very faint, and it is readily incorporated noise, noise will be led greatly very much The measurement minimum precision of current probe is caused to become larger, probe performance is deteriorated.In order to reduce the noise of the part, therefore in differential amplification One RC filter circuit is set after device, so as to inhibit noise well, improves signal-to-noise ratio, improves the property of current probe Energy.
Specifically, as shown in figure 9, the feedback system circuit 207 includes one first digital adjustable potentiometer 229；It is described First digital adjustable potentiometer 229 include the first pin connecting pin A1, second pin connecting pin A2, third pin connecting pin B1, 4th pin connecting pin B2, the 5th pin connecting pin W1, the 6th pin connecting pin W2, ground terminal GND, operating voltage connecting pin VDD, bi-directional data connection line end SDA and clock connect line end SCL.
The ground terminal GND ground connection；The operating voltage connecting pin VDD is loaded with positive 5 volts of voltage；The bi-directional data connects Terminals SDA and clock connection line end SCL pass through the I2C bus bi-directional data with described control unit circuit 254 respectively Signal output end (SDA) connects (SCL) with clock signal output terminal；First pin connecting pin A1 and the 5th pin connecting pin W1 is connected；Positive 12 volts of voltage is loaded with after one second resistance 230 of second pin connecting pin A2 connection；4th pin Minus 12 volts of voltage is loaded with after one 3rd resistor 231 of connecting pin B2 connection.
Specifically, as shown in Figure 10, the operation amplifier circuit 205 includes: operational amplifier 232, the 4th resistance 233, the 5th resistance 234, the 6th resistance 235 and first capacitor 236.
The operational amplifier 232 is loaded with positive 12V voltage and negative 12V voltage；The reverse phase of the operational amplifier 232 is defeated Enter end to connect by the 4th resistance 233 with the output end of the RC filter circuit 221；The operational amplifier 232 it is same Phase input terminal is separately connected one end of the 5th resistance 234 and one end of the 6th resistance 235；5th resistance 234 it is another Non-inverting input terminal of the one end as operation amplifier circuit 205；The other end of 6th resistance 235 is grounded；The operation is put The output end of big device 232 connect the both ends of the first capacitor 236 with the inverting input terminal of operational amplifier 232；The operation The output end of amplifier 232 is also connected with the third pin connecting pin B1 of the first digital adjustable potentiometer 229 described in Fig. 9；It is described The inverting input terminal of operational amplifier 232 is also connected with the first pin connecting pin of the first digital adjustable potentiometer 229 described in Fig. 9 A1。
It is specific as shown in figure 11, the power amplifier circuit 206 include: power amplifier 237, the 7th resistance 238, 8th resistance 239, the 9th resistance 240 and the tenth resistance 241.
The power amplifier 237 is loaded with positive 12V voltage and negative 12V voltage；The reverse phase of the power amplifier 237 is defeated Enter end to connect by the 8th resistance 239 with the output end of the operational amplifier 232 in Figure 10；The power amplifier 237 non-inverting input terminal is separately connected one end of the 9th resistance 240 and one end of the tenth resistance 241；9th resistance Non-inverting input terminal of 240 other end as the power amplifier circuit 206；The other end of tenth resistance 241 is grounded； The output end of the power amplifier 237 connect the two of the 7th resistance 238 with the inverting input terminal of power amplifier 237 End；The output end of the power amplifier 237 is also used in conjunction in the one end for connecing the secondary winding coil 214.
It is specific as shown in figure 12, the direct current calibration signal generation circuit 209 includes: direct current CALIBRATION AMPLIFIER 242, the 11 resistance 243, twelfth resistor 244 and the second capacitor 245.
The direct current calibration operational amplifier 242 is loaded with positive 12V voltage and negative 12V voltage；The direct current calibrates operation The inverting input terminal of amplifier 242 passes through the eleventh resistor 243 and the shown in Fig. 9 described first digital adjustable potentiometer 229 the 6th pin connecting pin W2 connection；The non-inverting input terminal of the direct current calibration operational amplifier 242 passes through the described 12nd Resistance 244 is connect with the output end of direct current calibration operational amplifier 242；The direct current calibrates the defeated of operational amplifier 242 Outlet also passes through second capacitor 245 and is grounded；The output end of the direct current calibration operational amplifier 242 is as the direct current school The output end of calibration signal generation circuit 209.
Specific as shown in figure 13, the demagnetization signal generating circuit 208 includes: demagnetization operational amplifier the 246, the 13rd Resistance 247, the 14th resistance 248, the 15th resistance 249, the 16th resistance 250, third capacitor 251, the 4th capacitor 252 and 5th capacitor 253.
The demagnetization operational amplifier 246 is loaded with positive 12V voltage and negative 12V voltage；The demagnetization operational amplifier 246 Inverting input terminal pass through the 14th resistance 248 be grounded；The non-inverting input terminal of the demagnetization operational amplifier 246 passes through the It is grounded after the parallel circuit of four capacitors 252 and the 15th resistance 249 composition；The homophase input of the demagnetization operational amplifier 246 The demagnetization operational amplifier is connected after the series circuit that end is also made up of the 5th capacitor 253 and the 16th resistance 250 246 output end；The output end of the demagnetization operational amplifier 246 and the degaussing control signal of described control unit circuit 254 Output end connection；The output end of the demagnetization operational amplifier 246 also passes through the third capacitor 251 and thirteenth resistor 247 It is grounded after the parallel circuit of composition；The output end of the demagnetization operational amplifier 246 is as the demagnetization signal generating circuit 208 Output end.
For demagnetization signal generating circuit 208 shown in Figure 13, it is understood that, the ferromagnetic material of high magnetic permeability can It is exactly that the magnetic that direction alternately changes can be generated by AC signal driving coil by applying opposing magnetic field appropriate , demagnetization can be carried out to magnetic core with the magnetic field.Or apply high temperature or vibration to it to reach decrease or eliminate remanent magnetism.At this Magnetic core is exactly placed in alternating magnetic field by the demagnetization method used in inventive embodiments, it is made to lose magnetism.Firstly, design is sinusoidal Wave generation circuit generates sinusoidal signal, as demagnetization signal, generates magnetic direction with the sinusoidal signal driving coil and alternately changes Magnetic field, the demagnetization of magnetic core is carried out with the magnetic field.And the demagnetization signal is to be added to by operational amplifier on the coil of magnetic head, Signal generates direction alternating changing magnetic field on coil, also, its range value is also gradually reduced, and the mesh of demagnetization can be realized 's.Demagnetization signal generating circuit 208 in Figure 13 can use Wien bridge circuit oscillating circuit.The circuit can generate certain amplitude one Determine the sinusoidal signal of frequency, the sinusoidal signal is finally input to one direction of generation in coil and replaces changing magnetic field at any time For carrying out demagnetization to magnetic core.
In addition, as shown in figure 14, which can use 5 rank Butterworth filter circuits.Wherein 5 rank The left end of Butterworth filter circuit connects transmission cable 223, and right end connects output impedance match circuit 225 and high frequency connects Connect device 226.
The 5 rank Butterworth LPF circuit includes: digital adjustable condenser 255, the first inductance 256, second Inductance 257, the 6th capacitor 258, the 7th capacitor 259, the 8th capacitor 260 and the 9th capacitor 261.The number adjustable condenser 255 include enable signal connecting pin SEN, the first ground connecting pin GND1, the second ground connecting pin GND2, third connecting pin GND3, 4th ground connecting pin GND4, clock signal connecting pin SCLK, voltage connection VDD, first capacitor device port RF-1, the second capacitor Device port RF-2, third capacitor ports RF+1, the 4th capacitor ports RF+2 and bi-directional data connecting pin SDAT.
One end of first inductance 256 connects the transmission cable 223, the other end connection of first inductance 256 One end of second inductance 257, the other end of second inductance 257 are connect with the output impedance match circuit 225；Institute The one end for stating the 6th capacitor 258 is connected to the junction of first inductance 256 and the transmission cable 223；7th electricity Hold 259 one end and one end of the 8th capacitor 260 is connected to the junction of first inductance 256 and second inductance 257； One end of 9th capacitor 261 is connected to the junction of second inductance 257 and the output impedance match circuit 225； The other end, the other end of the 7th capacitor 259 and the other end of the 9th capacitor 261 of 6th capacitor 258 are grounded；Described The other end of eight capacitors 260 connects the third capacitor ports RF+1 and the 4th capacitor ports RF+2；6th capacitor The other end of 258 other end, the other end of the 7th capacitor 259 and the 9th capacitor 261 is also connected with first capacitor device port RF-1 With the second capacitor ports RF-2；
First ground connecting pin GND1, the second ground connecting pin GND2, third ground connecting pin GND3, the 4th ground connecting pin GND4 is grounded respectively；The voltage connection VDD is loaded with positive 3.3 volts of voltage；Described in the enable signal connecting pin SEN connection The enable signal output end of control unit circuit 254；The clock signal connecting pin SCLK connection described control unit circuit 254 Clock signal output terminal；The bi-directional data of the bi-directional data connecting pin SDAT connection described control unit circuit 254 exports End.
In addition, as shown in figure 15, the left end of the output impedance match circuit 225 connects above-mentioned 5 rank Butterworths filter Wave circuit, right end connect high frequency connectors 226.The output impedance match circuit 225 includes the second digital adjustable potentiometer 262, the 17th resistance 263, the 18th resistance 264, the 19th resistance 265 and the 20th resistance 266；Second number is adjustable Potentiometer 262 includes the first pin connecting pin A1, second pin connecting pin A2, third pin connecting pin B1, the connection of the 4th pin B2, the 5th pin connecting pin W1, the 6th pin connecting pin W2, ground terminal GND, operating voltage connecting pin VDD, bi-directional data is held to connect Terminals SDA and clock connect line end SCL；
One end of 17th resistance 263, one end of the 18th resistance 264, the 19th resistance 265 one end and second One end of ten resistance 266 is separately connected 5 rank Butterworth LPF circuits and high frequency connectors 226；Described 17th The other end of the other end of resistance 263, the other end of the 18th resistance 264 and the 19th resistance 265 is grounded；Described 20th 4th pin connecting pin B2 of the digital adjustable potentiometer 262 of other end connection second of resistance 266.
Second pin connecting pin A2, the 6th pin connecting pin W2 and the ground terminal of described second digital adjustable potentiometer 262 GND ground connection；The operating voltage connecting pin VDD of described second digital adjustable potentiometer 262 is loaded with positive 3.3 volts of voltage；Described The bi-directional data connection line end SDA and clock connection line end SCL of two digital adjustable potentiometers 262 by I2C bus respectively with institute The bi-direction data signal output end for stating control unit circuit 254 is connected with clock signal output terminal.
In addition, as shown in figure 16, which can use high frequency output terminal BNC (Bayonet Nut Connector it) realizes.Wherein high frequency output terminal BNC can connect the AFE(analog front end) 301 of oscillograph 30 (in Figure 16 not It shows).
Herein, as shown in figure 17, which can be realized by single chip circuit, in Figure 17, SDA and SCL is the bi-direction data signal output end and clock signal output terminal for respectively indicating control unit circuit 254, and SEN_1 is control The enable signal output end of element circuit 254, SCL_1 are the clock signal output terminal connecting with clock signal connecting pin SCLK, SDA_1 is the bi-directional data output end connecting with bi-directional data connecting pin SDAT.Demagnetizing_control_signal For degaussing control signal output end.Since control unit circuit 254 can be using current more mature singlechip technology, tool Details are not described herein again for body mode.
A kind of current probe provided in an embodiment of the present invention, by the way that two output ends of Hall sensor are separately connected difference Divide amplifier circuit non-inverting input terminal and inverting input terminal, and not one end ground connection of Hall sensor, the other end connect difference Amplifier circuit avoids asymmetry of the hall device due to bias voltage itself so that the output of Hall sensor balances, and is not having There is signal output to cause the problem of the measurement result inaccuracy of current probe in the case where having measured conductor.In addition, the present invention is real The circuit structure that example preferably selects the three-level signal of difference amplifier, operational amplifier and power operational amplifier to amplify is applied, And by demagnetization signal generating circuit and direct current calibration signal generation circuit respectively by demagnetization signal and direct current calibration signal simultaneously It is introduced into current probe circuit, it, can be at any time to closed magnetic core into the magnetic head row of formation in the case where not influencing current measurement Demagnetization and progress offset correction, can be to avoid the problem of the measurement result inaccuracy of current probe in the prior art.In addition, should The first order of the circuit structure of three-level signal amplification uses differential amplifier circuit, has and inhibits common-mode noise well, improves letter The effect of number quality.
In addition, it is worth noting that, the embodiment of the present invention can pass through micro-control unit (Microcontroller Unit, abbreviation MCU) control each road signal and switch, to apply the current probe, to realize demagnetization and direct current calibration Automatic operation.
As shown in figure 18, the embodiment of the present invention provides a kind of control method of current probe, visits applied to above-mentioned electric current Head；The described method includes:
Step 401 passes through control unit circuit control feedback system circuit, carries out the automatic frequency response calibration of current probe.
It herein, in step 401, can be defeated by the bi-direction data signal output end and clock signal of control unit circuit Outlet adjusts the resistance value of the first digital adjustable potentiometer, carries out the automatic frequency response calibration of current probe.
Wide band current probe is carried out the measurement of low-frequency current signal using Hall element, carries out high frequency by coil The measurement of current signal.This requires the amplitude-frequency characteristics of low-frequency range and the amplitude-frequency characteristic of high band unanimously just can guarantee in this way Amplitude-frequency response characteristic of the current probe in wider frequency range is very flat.Here by the anti-of adjusting two-level operating amplifier Feed hinders to adjust the amplitude-frequency characteristic of low-frequency range, is consistent it with high band, to realize the amplitude-frequency characteristic tool of height frequency range There is good consistency.
Step 402 passes through control unit circuit control demagnetization signal generating circuit, progress current probe demagnetization control.
In step 402, degaussing control signal can be generated by the degaussing control signal output end of control unit circuit, So that third capacitor carries out charge and discharge, the sinusoidal letter that range value is gradually reduced is generated in the output end of demagnetization signal generating circuit Number, carry out current probe demagnetization control.
Herein, the principle for carrying out demagnetization to magnetic core is to magnetic core plus direction alternately variation, the magnetic of range value from large to small ?.It can make the magnetic domain in magnetic core with certain orientation, direction becomes disorder, loses magnetism, and achievees the purpose that demagnetization.
Demagnetization signal generating circuit can use Wien-bridge oscillator circuit.When to the fortune in demagnetization signal generating circuit After calculating amplifier (or be trsanscondutance amplifier) power supply, the 4th pin of the operational amplifier will output frequency are as follows: f=1/ (2 π RC sinusoidal signal), the resistance value of R is the resistance value of the 16th resistance herein, and the capacitance of C is the capacitance of the 5th capacitor.
Degaussing control signal has been connected to the output control terminal of trsanscondutance amplifier, and when demagnetization signal is high level, mutual conductance is put Big device can export sine wave signal.When degaussing control signal is low level, trsanscondutance amplifier is not exported, and is at this time low electricity It is flat.Circuit structure in parallel with a resistor is held in power-up on the path of demagnetization signal input, in order to realize a kind of delay effect.When disappearing It is first third capacitor charging, when degaussing control signal is hanging, third capacitor starts to put when magnetic control signal is high level Electricity, can make the output end level of trsanscondutance amplifier have the process of a holding in this way, and level is gradually reduced.Final effect It is that the range value of sinusoidal signal is gradually reduced by a determining value.It thus can produce a range value from large to small just String signal, the sinusoidal signal go driving coil generate direction at any time replace changing magnetic field, magnetic field strength from large to small, in this way Magnetic field the demagnetization function of magnetic core can be realized in magnetic core.
Step 403 passes through control unit circuit control direct current calibration signal generation circuit, and the direct current for carrying out current probe is inclined Transposition section.
In step 403, the first digital adjustable potentiometer can be adjusted by control unit circuit, change direct current calibration letter The direct current signal of number generation circuit output, the direct current offset for carrying out current probe are adjusted.First digital adjustable potentiometer and second Resistance and 3rd resistor constitute a bleeder circuit, generate a direct current signal, by controlling the first digital adjustable potentiometer, Change the size of this direct current signal.Such first digital adjustable potentiometer and third operational amplifier constitute a generation can The direct current signal circuit of adjusting.This direct current signal is inputted from the in-phase end of third operational amplifier, with third operational amplifier Reverse side input Signal averaging, realize the adjusting of the direct current offset of signal, that is, realize the automatic zero set of current probe.
Step 404 passes through control unit circuit control filter circuit, carries out the bandwidth control of current probe.
In step 404, the capacitance that digital adjustable condenser can be adjusted by control unit circuit control, carries out electricity The bandwidth control of stream probe.Filter circuit is using 5 rank Butterworth LPF circuits, by modifying in the circuit The first inductance and the second inductance between capacitor total value, thus it is possible to vary the performance parameter of the 5 rank Butterworth filter.It will Digital adjustable condenser connects between network RF+ and RF-, changes the capacitance of digital adjustable condenser by iic bus, so that it may Amplitude-frequency characteristic flatness and control system bandwidth are adjusted by 5 rank Butterworth LPFs.
Step 405 passes through control unit circuit control output impedance match circuit, carries out the DC precision tune of current probe Section.
Here in step 405, the resistance value of the second digital adjustable potentiometer can be adjusted by control unit circuit control, The DC precision for carrying out current probe is adjusted.Because the second digital adjustable potentiometer connect output impedance match circuit RL_A and Between RL_B, so that control unit circuit just changes the resistance of terminating resistor by the resistance value of the digital adjustable potentiometer of control second The output resistance of value, terminating resistor and current probe constitutes bleeder circuit, adjustable DC precision.
A kind of control method of current probe provided in an embodiment of the present invention can control feedback by control unit circuit Circuit system carries out the automatic frequency response calibration of current probe；Demagnetization signal generating circuit is controlled, current probe demagnetization control is carried out System；Direct current calibration signal generation circuit is controlled, the direct current offset for carrying out current probe is adjusted；Filter circuit is controlled, electricity is carried out The bandwidth control of stream probe；Output impedance match circuit is controlled, the DC precision for carrying out current probe is adjusted, to avoid electric current There is very complicated in the detection of each performance indicator after the completion of production of probe and calibration process.
It should be understood by those skilled in the art that, the embodiment of the present invention can provide as method, system or computer program Product.Therefore, complete hardware embodiment, complete software embodiment or reality combining software and hardware aspects can be used in the present invention Apply the form of example.Moreover, it wherein includes the computer of computer usable program code that the present invention, which can be used in one or more, The computer program implemented in usable storage medium (including but not limited to magnetic disk storage, CD-ROM, optical memory etc.) produces The form of product.
The present invention be referring to according to the method for the embodiment of the present invention, the process of equipment (system) and computer program product Figure and/or block diagram describe.It should be understood that every one stream in flowchart and/or the block diagram can be realized by computer program instructions The combination of process and/or box in journey and/or box and flowchart and/or the block diagram.It can provide these computer programs Instruct the processor of general purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices to produce A raw machine, so that being generated by the instruction that computer or the processor of other programmable data processing devices execute for real The device for the function of being specified in present one or more flows of the flowchart and/or one or more blocks of the block diagram.
These computer program instructions, which may also be stored in, is able to guide computer or other programmable data processing devices with spy Determine in the computer-readable memory that mode works, so that it includes referring to that instruction stored in the computer readable memory, which generates, Enable the manufacture of device, the command device realize in one box of one or more flows of the flowchart and/or block diagram or The function of being specified in multiple boxes.
These computer program instructions also can be loaded onto a computer or other programmable data processing device, so that counting Series of operation steps are executed on calculation machine or other programmable devices to generate computer implemented processing, thus in computer or The instruction executed on other programmable devices is provided for realizing in one or more flows of the flowchart and/or block diagram one The step of function of being specified in a box or multiple boxes.
Specific embodiment is applied in the present invention, and principle and implementation of the present invention are described, above embodiments Explanation be merely used to help understand method and its core concept of the invention；At the same time, for those skilled in the art, According to the thought of the present invention, there will be changes in the specific implementation manner and application range, in conclusion in this specification Appearance should not be construed as limiting the invention.

Claims (20)

1. a kind of current probe, which is characterized in that including be made of upper magnetic core and lower magnetic core closed magnetic core, Hall sensor, Differential amplifier circuit, operation amplifier circuit, feedback system circuit, the first parallel end connection resistance, signal output apparatus and control Element circuit processed；
The Hall sensor is embedded in one side of the lower magnetic core, and passes through and have in the magnetic head of the lower magnetic core and upper magnetic core composition Measured wire；Two output ends of the Hall sensor be separately connected differential amplifier circuit non-inverting input terminal and reverse phase it is defeated Enter end；The output end of the differential amplifier circuit is connected to the inverting input terminal of the operation amplifier circuit；The feedback Circuit system is connected between the inverting input terminal and output end of the operation amplifier circuit；The lower magnetic core is wound with tested lead The opposite side on one side of line is wound with secondary winding coil, and one end of the secondary winding coil connects the operation amplifier circuit Output end, the other end of the secondary winding coil connect one end and the signal output apparatus of the first parallel end connection resistance； The other end of the first parallel end connection resistance is grounded；
Feedback system circuit described in described control unit circuit connection, to carry out the automatic frequency response calibration of current probe.
2. current probe according to claim 1, which is characterized in that the current probe further includes power amplifier circuit With direct current calibration signal generation circuit；The inverting input terminal of the power amplifier circuit is defeated with the operation amplifier circuit Outlet connection, the output end of the power amplifier circuit are connect with one end of the secondary winding coil；The direct current calibration The non-inverting input terminal of the non-inverting input terminal or operation amplifier circuit of signal generating circuit and the power amplifier circuit connects It connects；
Described control unit circuit is also connected with the direct current calibration signal generation circuit, to carry out the direct current offset tune of current probe Section.
3. current probe according to claim 2, which is characterized in that the current probe further includes that demagnetization signal generates electricity Road；The non-inverting input terminal of the demagnetization signal generating circuit and the power amplifier circuit or operation amplifier circuit it is same The connection of phase input terminal；
Described control unit circuit is also connected with the demagnetization signal generating circuit, to carry out current probe demagnetization control.
4. current probe according to claim 2, which is characterized in that the signal output apparatus includes an output stage operation Amplifier circuit；The other end of the secondary winding coil connect the first parallel end connection resistance one end and the output stage The input terminal of operation amplifier circuit；Measurement of the output end of the output stage operation amplifier circuit as the current probe Output end.
5. current probe according to claim 3, which is characterized in that the Hall sensor has first input end, the Two input terminals, the first output end and second output terminal；The first input end and the second input terminal connect the system power supply electricity The power supply output end on road；
First output end connects the non-inverting input terminal of the differential amplifier circuit, and the second output terminal connects the difference Divide the inverting input terminal of amplifier circuit；The reverse phase of the output end of the differential amplifier circuit and the operation amplifier circuit RC filter circuit is additionally provided between input terminal；The input of the output end connection RC filter circuit of the differential amplifier circuit End, the inverting input terminal of the output end connection operation amplifier circuit of RC filter circuit.
6. current probe according to claim 5, which is characterized in that the signal output apparatus includes series termination electricity Resistance, transmission cable, filter circuit, output impedance match circuit and high frequency connectors；
One end of the series termination resistance is connect with the other end of the secondary winding coil；The series termination resistance it is another One end is sequentially connected the transmission cable, filter circuit and high frequency connectors；The filter circuit is connect with the high frequency The junction of device connects one end of the output impedance match circuit, the other end ground connection of the output impedance match circuit；Institute High frequency connectors are stated for connecting with the AFE(analog front end) of oscillograph；
Described control unit circuit is also connect with the filter circuit and output impedance match circuit respectively, to carry out electricity respectively The bandwidth control of stream probe and the DC precision of current probe are adjusted.
7. current probe according to claim 6, which is characterized in that the differential amplifier circuit includes a differential amplification Device chip；The difference amplifier chip include inverting input terminal IN-, non-inverting input terminal IN+, first resistor connecting pin Rg1, Second resistance connecting pin Rg2, positive pole connecting pin Vs+, power cathode connecting pin Vs ﹣, output end vo ut and reference voltage connect Meet end REF；
First output end of the Hall sensor connects the inverting input terminal IN ﹣；Second output of the Hall sensor End connects the non-inverting input terminal IN+；
The first resistor connecting pin Rg1 is connected with second resistance connecting pin Rg2 by a first resistor；
The positive pole connecting pin Vs+ is loaded with positive 12 volts of voltage；The power cathode connecting pin Vs ﹣ is loaded with minus 12 volts of electricity Pressure；
The reference voltage connecting pin REF ground connection；
The output end vo ut connects the input terminal of the RC filter circuit.
8. current probe according to claim 7, which is characterized in that the feedback system circuit includes one first number can Adjust potentiometer；Described first digital adjustable potentiometer includes the first pin connecting pin A1, second pin connecting pin A2, third pin Connecting pin B1, the 4th pin connecting pin B2, the 5th pin connecting pin W1, the 6th pin connecting pin W2, ground terminal GND, work electricity Connecting pin VDD, bi-directional data connection line end SDA and clock is pressed to connect line end SCL；
The ground terminal GND ground connection；The operating voltage connecting pin VDD is loaded with positive 5 volts of voltage；The bi-directional data connecting line Hold SDA and clock connection line end SCL by I2C bus respectively with the bi-direction data signal output end of described control unit circuit and Clock signal output terminal connection；First pin connecting pin A1 and the 5th pin connecting pin W1 are connected；The second pin Positive 12 volts of voltage is loaded with after one second resistance of connecting pin A2 connection；After 4th pin connecting pin B2 connection, one 3rd resistor It is loaded with minus 12 volts of voltage.
9. current probe according to claim 8, which is characterized in that the operation amplifier circuit includes: operation amplifier Device, the 4th resistance, the 5th resistance, the 6th resistance and first capacitor；
The operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The inverting input terminal of the operational amplifier passes through institute The 4th resistance is stated to connect with the output end of the RC filter circuit；The non-inverting input terminal of the operational amplifier is separately connected described One end of 5th resistance and one end of the 6th resistance；The other end of 5th resistance is as the same of the operation amplifier circuit Phase input terminal；The other end of 6th resistance is grounded；The output end of the operational amplifier and the reverse phase of operational amplifier are defeated Enter the both ends that end connects the first capacitor；The output end of the operational amplifier is also connected with the described first digital adjustable potentiometer Third pin connecting pin B1；The inverting input terminal of the operational amplifier is also connected with the of the described first digital adjustable potentiometer One pin connecting pin A1.
10. current probe according to claim 9, which is characterized in that the power amplifier circuit includes: power amplification Device, the 7th resistance, the 8th resistance, the 9th resistance and the tenth resistance；
The power amplifier is loaded with positive 12V voltage and negative 12V voltage；The inverting input terminal of the power amplifier passes through institute The 8th resistance is stated to connect with the output end of the operational amplifier；The non-inverting input terminal of the power amplifier is separately connected described One end of 9th resistance and one end of the tenth resistance；The other end of 9th resistance is as the same of the power amplifier circuit Phase input terminal；The other end of tenth resistance is grounded；The output end of the power amplifier and the reverse phase of power amplifier are defeated Enter the both ends that end connects the 7th resistance；The output end of the power amplifier is also connected with the one of the secondary winding coil End.
11. current probe according to claim 10, which is characterized in that the direct current calibration signal generation circuit includes: Direct current calibrates operational amplifier, eleventh resistor, twelfth resistor and the second capacitor；
The direct current calibration operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The direct current calibration operational amplifier Inverting input terminal is connect by the eleventh resistor with the 6th pin connecting pin W2 of the described first digital adjustable potentiometer；Institute The non-inverting input terminal for stating direct current calibration operational amplifier calibrates operational amplifier by the twelfth resistor and the direct current Output end connection；The output end of the direct current calibration operational amplifier also passes through second capacity earth；The direct current calibration Output end of the output end of operational amplifier as the direct current calibration signal generation circuit.
12. current probe according to claim 11, which is characterized in that the demagnetization signal generating circuit includes: demagnetization Operational amplifier, thirteenth resistor, the 14th resistance, the 15th resistance, the 16th resistance, third capacitor, the 4th capacitor and 5th capacitor；
The demagnetization operational amplifier is loaded with positive 12V voltage and negative 12V voltage；The anti-phase input of the demagnetization operational amplifier End passes through the 14th resistance eutral grounding；The non-inverting input terminal of the demagnetization operational amplifier passes through the 4th capacitor and the 15th electricity It is grounded after hindering the parallel circuit of composition；The non-inverting input terminal of the demagnetization operational amplifier also passes through the 5th capacitor and the tenth The output end of the demagnetization operational amplifier is connected after the series circuit of six resistance composition；The output of the demagnetization operational amplifier End is connect with the degaussing control signal output end of described control unit circuit；The output end of the demagnetization operational amplifier also passes through It is grounded after the parallel circuit of the third capacitor and thirteenth resistor composition；The output end of the demagnetization operational amplifier is as institute State the output end of demagnetization signal generating circuit.
13. current probe according to claim 12, which is characterized in that the filter circuit is that 5 rank Butterworths are low Bandpass filter circuit；The 5 rank Butterworth LPF circuit includes: digital adjustable condenser, the first inductance, the second electricity Sense, the 6th capacitor, the 7th capacitor, the 8th capacitor and the 9th capacitor；The number adjustable condenser includes enable signal connection Hold SEN, the first ground connecting pin GND1, the second ground connecting pin GND2, third connecting pin GND3, the 4th ground connecting pin GND4, when Clock signal connection end SCLK, voltage connection VDD, first capacitor device port RF-1, the second capacitor ports RF-2, third capacitor Device port RF+1, the 4th capacitor ports RF+2 and bi-directional data connecting pin SDAT；
One end of first inductance connects the transmission cable, and the other end of first inductance connects second inductance One end, the other end of second inductance are connect with the output impedance match circuit；One end of 6th capacitor is connected to The junction of first inductance and the transmission cable；One end of 7th capacitor and one end of the 8th capacitor are connected to institute State the junction of the first inductance Yu second inductance；One end of 9th capacitor be connected to second inductance with it is described defeated The junction of impedance matching circuit out；The other end of 6th capacitor, the other end of the 7th capacitor and the 9th capacitor it is another End is grounded；The other end of 8th capacitor connects the third capacitor ports RF+1 and the 4th capacitor ports RF+2； The other end, the other end of the 7th capacitor and the other end of the 9th capacitor of 6th capacitor are also connected with first capacitor device port RF-1 and the second capacitor ports RF-2；
First ground connecting pin GND1, the second ground connecting pin GND2, third ground connecting pin GND3, the 4th ground connecting pin GND4 point It is not grounded；The voltage connection VDD is loaded with positive 3.3 volts of voltage；The enable signal connecting pin SEN connection control is single The enable signal output end of first circuit；The clock signal of the clock signal connecting pin SCLK connection described control unit circuit is defeated Outlet；The bi-directional data output end of the bi-directional data connecting pin SDAT connection described control unit circuit.
14. current probe according to claim 13, which is characterized in that the output impedance match circuit includes the second number Word adjustable potentiometer, the 17th resistance, the 18th resistance, the 19th resistance and the 20th resistance；Described second digital adjustable electric Position device include the first pin connecting pin A1, second pin connecting pin A2, third pin connecting pin B1, the 4th pin connecting pin B2, 5th pin connecting pin W1, the 6th pin connecting pin W2, ground terminal GND, operating voltage connecting pin VDD, bi-directional data connecting line SDA and clock is held to connect line end SCL；
One end of 17th resistance, the 18th resistance one end, one end of the 19th resistance and one end of the 20th resistance It is separately connected 5 rank Butterworth LPF circuits and high frequency connectors；The other end of 17th resistance, the 18th The other end of the other end of resistance and the 19th resistance is grounded；The second number of other end connection of 20th resistance is adjustable 4th pin connecting pin B2 of potentiometer；
Second pin connecting pin A2, the 6th pin connecting pin W2 of described second digital adjustable potentiometer and ground terminal GND ground connection； The operating voltage connecting pin VDD of described second digital adjustable potentiometer is loaded with positive 3.3 volts of voltage；Described second digital adjustable electric Position device bi-directional data connection line end SDA and clock connection line end SCL by I2C bus respectively with described control unit circuit Bi-direction data signal output end is connected with clock signal output terminal.
15. a kind of control method of current probe, which is characterized in that applied to the current probe described in claim 14；It is described Method includes:
By control unit circuit control feedback system circuit, the automatic frequency response calibration of current probe is carried out；
By control unit circuit control demagnetization signal generating circuit, current probe demagnetization control is carried out；
By control unit circuit control direct current calibration signal generation circuit, the direct current offset for carrying out current probe is adjusted；
By control unit circuit control filter circuit, the bandwidth control of current probe is carried out；
By control unit circuit control output impedance match circuit, the DC precision for carrying out current probe is adjusted.
16. the control method of current probe according to claim 15, which is characterized in that described to pass through control unit circuit Feedback system circuit is controlled, the automatic frequency response calibration of current probe is carried out, comprising:
The first digital adjustable potential is adjusted by the bi-direction data signal output end and clock signal output terminal of control unit circuit The resistance value of device carries out the automatic frequency response calibration of current probe.
17. the control method of current probe according to claim 15, which is characterized in that pass through control unit circuit control Demagnetization signal generating circuit carries out current probe demagnetization control, comprising:
Degaussing control signal is generated by the degaussing control signal output end of control unit circuit, so that third capacitor carries out charge and discharge Electricity generates the sinusoidal signal that range value is gradually reduced in the output end of demagnetization signal generating circuit, carries out current probe demagnetization control System.
18. the control method of current probe according to claim 15, which is characterized in that pass through control unit circuit control Direct current calibration signal generation circuit, the direct current offset for carrying out current probe are adjusted, comprising:
The first digital adjustable potentiometer is adjusted by control unit circuit, changes the direct current of direct current calibration signal generation circuit output Signal, the direct current offset for carrying out current probe are adjusted.
19. the control method of current probe according to claim 15, which is characterized in that pass through control unit circuit control Filter circuit carries out the bandwidth control of current probe, comprising:
The capacitance that digital adjustable condenser is adjusted by control unit circuit control carries out the bandwidth control of current probe.
20. the control method of current probe according to claim 15, which is characterized in that pass through control unit circuit control Output impedance match circuit, the DC precision for carrying out current probe are adjusted, comprising:
The resistance value that the second digital adjustable potentiometer is adjusted by control unit circuit control, carries out the DC precision tune of current probe Section.
CN201710436006.7A 2017-06-09 2017-06-09 Current probe and control method thereof Active CN109030907B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710436006.7A CN109030907B (en) 2017-06-09 2017-06-09 Current probe and control method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710436006.7A CN109030907B (en) 2017-06-09 2017-06-09 Current probe and control method thereof

Publications (2)

Publication Number Publication Date
CN109030907A true CN109030907A (en) 2018-12-18
CN109030907B CN109030907B (en) 2022-02-25

Family

ID=64630036

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710436006.7A Active CN109030907B (en) 2017-06-09 2017-06-09 Current probe and control method thereof

Country Status (1)

Country Link
CN (1) CN109030907B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110599935A (en) * 2019-08-26 2019-12-20 昆山龙腾光电有限公司 Automatic adjusting device and automatic adjusting method for public voltage
CN113625032A (en) * 2021-07-01 2021-11-09 普源精电科技股份有限公司 Probe measurement system and method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001272423A (en) * 2000-03-23 2001-10-05 Yazaki Corp Non-contact sensor and offset adjustment method for the sensor
CN2831141Y (en) * 2005-06-02 2006-10-25 南阳孚达光电技术有限公司 Annular ferrite current sensor
CN202886448U (en) * 2012-10-08 2013-04-17 北京动力源科技股份有限公司 Current detection circuit
CN204302358U (en) * 2014-12-25 2015-04-29 南京中旭电子科技有限公司 A kind of big current Hall element

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001272423A (en) * 2000-03-23 2001-10-05 Yazaki Corp Non-contact sensor and offset adjustment method for the sensor
CN2831141Y (en) * 2005-06-02 2006-10-25 南阳孚达光电技术有限公司 Annular ferrite current sensor
CN202886448U (en) * 2012-10-08 2013-04-17 北京动力源科技股份有限公司 Current detection circuit
CN204302358U (en) * 2014-12-25 2015-04-29 南京中旭电子科技有限公司 A kind of big current Hall element

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110599935A (en) * 2019-08-26 2019-12-20 昆山龙腾光电有限公司 Automatic adjusting device and automatic adjusting method for public voltage
CN110599935B (en) * 2019-08-26 2023-01-24 昆山龙腾光电股份有限公司 Automatic adjusting device and automatic adjusting method for public voltage
CN113625032A (en) * 2021-07-01 2021-11-09 普源精电科技股份有限公司 Probe measurement system and method

Also Published As

Publication number Publication date
CN109030907B (en) 2022-02-25

Similar Documents

Publication Publication Date Title
CN106066425B (en) A kind of impedance measurement device and its method for realizing compensation for calibrating errors
CN106501562B (en) Isolated differential voltage probe for EMI noise sources
CN104374979B (en) Digital alternating current resistance electrical bridge
CN103529268A (en) AC bridge with automatic auxiliary balancing function and impedance measurement method
CN202066910U (en) Device for measuring resistance, inductance and capacitance
US6414476B2 (en) Current detecting device, impedance measuring instrument and power measuring instrument
CN104237832B (en) A kind of calibration method and device of complex impedance standard
CN104459330B (en) High-voltage transmission line zero-sequence impedance measuring circuit and method
CN109030906A (en) A kind of current probe
CN107592087B (en) Synthetic inductance circuit
CN109030907B (en) Current probe and control method thereof
CN204065391U (en) A kind of wideband current transformer calibrator
CN101872006A (en) Electronic voltage transformer periodic non-sinusoidal reference with booster
CN205920176U (en) Exchange electric capacity characteristics measurement equipment under carrier wave wantonly
JP6960655B2 (en) Magnetic property measurement method for magnetic materials and magnetic property measurement device for magnetic materials
KR20050063872A (en) An electronically compensated current transformer for instrumentation
CN212540540U (en) Circuit for realizing alternating current impedance measurement by adopting transconductance shunting structure
GB531477A (en) Improvements in apparatus for measuring the loss angle of dielectrics
JP6467297B2 (en) Noise voltage measuring device and noise voltage measuring method
Bauer et al. Progress on PTB's Pulse-Driven Josephson Impedance Bridge Combined with an AC Quantum Hall Resistance
CN101701977B (en) Single-ended electrical signal measuring instrument
CN106483385B (en) A kind of dielectric loss measurement system and measurement method based on feedthrough transformer
CN106199285A (en) The arbitrarily capacitance characteristic under AC carrier measures equipment and measuring method thereof
Slomovitz et al. Behavior of voltage transformers under distorted waveforms
CN206114743U (en) Power supply unit and distribution device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant