CN109696576A - Current sampling circuit and method, air conditioner frequency converter and air conditioner - Google Patents
Current sampling circuit and method, air conditioner frequency converter and air conditioner Download PDFInfo
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- CN109696576A CN109696576A CN201910136121.1A CN201910136121A CN109696576A CN 109696576 A CN109696576 A CN 109696576A CN 201910136121 A CN201910136121 A CN 201910136121A CN 109696576 A CN109696576 A CN 109696576A
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- 238000005070 sampling Methods 0.000 title claims abstract description 34
- 238000000034 method Methods 0.000 title claims description 16
- 238000004378 air conditioning Methods 0.000 claims description 20
- 239000004020 conductor Substances 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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- 239000004065 semiconductor Substances 0.000 description 1
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Classifications
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- 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
- 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
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The circuit comprises a current acquisition assembly and a processor, wherein the current acquisition assembly is arranged on a bus to be tested, and the processor is connected with the current acquisition assembly. The current acquisition assembly is used for sampling the bus to be tested, obtaining sampling current and sending the sampling current to the processor, and the processor performs differential processing on the sampling current to obtain a current sampling result of the bus to be tested. By carrying out differential processing on the acquired current, common mode interference can be cancelled, output waveform fidelity is realized, and current sampling reliability is improved.
Description
Technical field
This application involves technical field of electric device control, more particularly to a kind of current sampling circuit, method, air conditioning frequency converter
And air-conditioning.
Background technique
As the reach of science and social are constantly progressive, requirement of the people to living standard is also continuously improved.Air-conditioning is made
For the equipment that the parameters such as temperature, humidity to indoor air are adjusted and control, in people's routine work and life
Using also more and more extensive.Convertible frequency air-conditioner controls using frequency converter and adjusts compressor rotary speed, is allowed to always in optimal
Rotary regimes, to improve Energy Efficiency Ratio.
Frequency converter acquires bus current by Acquisition Circuit and adopts, and carries out power supply conversion according to the bus current collected
Control.Traditional current collection circuit is sampled by using Hall element, but since Hall element sampling is mostly analog quantity
Output, and analog quantity is easy to be interfered, and current sample is caused to have very big error.There is sampling in traditional current collection circuit
The low disadvantage of reliability.
Summary of the invention
Based on this, it is necessary to which, for the low problem of traditional current collection circuit sampling reliability, providing one kind can be improved
Current sampling circuit, method, air conditioning frequency converter and the air-conditioning of current sample reliability.
A kind of current sampling circuit, including current acquisition component and processor, the current acquisition component are set to be measured
Bus, the processor connect the current acquisition component,
The current acquisition component obtains sample rate current and is sent to the place for sampling to the bus to be measured
Device is managed, the processor carries out difference processing to the sample rate current and obtains the current sample result of the bus to be measured.
The current acquisition component includes the first electric current biography for being connected to the bus to be measured in one of the embodiments,
The polarity of sensor and the second current sensor, first current sensor and second current sensor is on the contrary, and connect
Connect the processor.
First current sensor and second current sensor are Hall current in one of the embodiments,
Sensor.
The processor is by first current sensor and second current sensor in one of the embodiments,
The sample rate current exported respectively as Differential Input, adopt by the electric current for being handled to obtain the bus to be measured to two-way sample rate current
Sample result.
The processor includes the first differential input end, the second differential input end and output in one of the embodiments,
End, the output cathode of first current sensor connect the first differential input end of the processor, and first electric current passes
The output negative pole of sensor is grounded, and the output negative pole of second current sensor connects the second Differential Input of the processor
End, the output cathode ground connection of second current sensor, the output end of the processor is for exporting the bus to be measured
Current sample result.
A kind of current sample method, comprising the following steps:
Reception is set to the sample rate current that the current acquisition component of bus to be measured samples the bus to be measured；
Difference processing is carried out to the sample rate current and obtains the current sample result of the bus to be measured.
The current acquisition component includes the first electric current biography for being connected to the bus to be measured in one of the embodiments,
The polarity of sensor and the second current sensor, first current sensor and second current sensor is opposite；It is described right
The sample rate current carries out difference processing and obtains the current sample result of the bus to be measured, comprising:
The sample rate current that first current sensor and second current sensor are exported respectively is defeated as difference
Enter, two-way sample rate current is handled to obtain the current sample result of the bus to be measured.
The electric current for obtaining the bus to be measured to sample rate current progress difference processing in one of the embodiments, is adopted
After sample result, further include the steps that exporting the current sample result.
A kind of air conditioning frequency converter, including above-mentioned current sampling circuit.
A kind of air-conditioning, including above-mentioned air conditioning frequency converter.
Above-mentioned current sampling circuit, method, air conditioning frequency converter and air-conditioning, current acquisition component sample bus to be measured
Sample rate current is obtained, difference processing is carried out to sample rate current and obtains the current sample result of bus to be measured.By to collecting
Electric current carry out difference processing, enable to common mode interference to offset, realize output waveform fidelity, it is reliable to improve current sample
Property.
Detailed description of the invention
Fig. 1 is the structural block diagram of current sampling circuit in an embodiment；
Fig. 2 is the structure principle chart of current acquisition component in an embodiment；
Fig. 3 is the structure principle chart of current sampling circuit in an embodiment；
Fig. 4 is the schematic illustration that Hall sensor analog output is disturbed in an embodiment；
Fig. 5 is the schematic illustration that current sampling circuit common mode interference is solved the problems, such as in an embodiment；
Fig. 6 is the flow chart of current sample method in an embodiment；
Fig. 7 is the flow chart of current sample method in another embodiment.
Specific embodiment
It is with reference to the accompanying drawings and embodiments, right in order to which the objects, technical solutions and advantages of the application are more clearly understood
The application is further elaborated.It should be appreciated that specific embodiment described herein is only used to explain the application, not
For limiting the application.
In one embodiment, a kind of current sampling circuit is provided, the current sample suitable for frequency converter.Such as Fig. 1 institute
Show, which includes current acquisition component 110 and processor 120, and current acquisition component 110 is set to bus to be measured, processor
120 connection current acquisition components 110.It is concurrent to obtain sample rate current for sampling to bus to be measured for current acquisition component 110
It send to processor 120, processor 120 carries out difference processing to sample rate current and obtains the current sample result of bus to be measured.Wherein,
Current acquisition component 110 carries out current sample to bus to be measured, generates two-way sample rate current and is sent to processor 120, processor
120 pairs of two-way sample rate currents carry out difference processing, so that common mode interference offsets, reduce external signal and do to current sample
It disturbs, realizes output waveform fidelity.
Specifically, the specific device of current acquisition component 110 and structure be not unique, need to only meet acquisition two-way sampling electricity
Stream carries out difference processing for processor.In one embodiment, as shown in Fig. 2, current acquisition component 110 includes being connected to
The first current sensor 112 and the second current sensor 114 of bus to be measured, the first current sensor 112 and the second electric current pass
The polarity of sensor 114 is on the contrary, and be all connected with processor 120.
Two opposite polarity two current sensors are attempted by bus to be measured, electric current is carried out to bus to be measured respectively
Sampling, output sample rate current to processor 120 carry out difference processing.First current sensor 112 and the second current sensor 114
Concrete type be not yet it is unique, in the present embodiment, the first current sensor 112 and the second current sensor 114 are
Hall current sensor.As shown in Fig. 2, bus to be measured passes through two Hall current sensors, and two Hall current sensors
Secondary side bucking coil be separately connected corresponding current source DC, the output cathode of the first current sensor 112 is as output end OUT
Processor 120 is connected, output negative pole connects ground terminal GND.The output negative pole of second current sensor 114 is as output end OUT1
Processor 120 is connected, output cathode connects ground terminal GND.Current sample is carried out using Hall current sensor, response is fast and can
Realize the electrical isolation of current sample, it is easy to operate reliable.
Accordingly, in one embodiment, processor 120 is by the first current sensor 112 and the second current sensor 114
The sample rate current exported respectively handles two-way sample rate current to obtain the current sample knot of bus to be measured as Differential Input
Fruit.Wherein, the two-way sample rate current that processor 120 exports the first current sensor 112 and the second current sensor 114 as
Differential Input carries out operation, and obtaining the result is that twice of virtual voltage, then processor 120 does obtained result at 1/2
Reason, just obtains the current sample result of bus to be measured.
Further, in one embodiment, as shown in figure 3, processor 120 includes the first differential input end X1, second
Differential input end X2With output end u1, the second Differential Input of the output cathode connection processor 120 of the first current sensor 112
Hold X2, the output negative pole ground connection of the first current sensor 112.The output negative pole of second current sensor 114 connects processor 120
The first differential input end X1, the output cathode ground connection of the second current sensor 114, the output end u of processor 1201For exporting
The current sample result of bus to be measured.Specifically, the output end u of processor 1201Peripheral control unit can be connected, for outside control
Device processed is controlled according to current sample result, or current sample result is exported to display and is shown.
For ease of understanding, below with current acquisition component 110 using two opposite polarity Hall current sensors into
For row current sample, it is explained.
Hall current sensor is a kind of using magnetoelastic transducer part made of semiconductor material, by measuring Hall voltage
Size measure the size of current-carrying conductor electric current indirectly.Therefore, current sensor have passed through electricity-magnetic-electricity and be dielectrically separated from and turns
It changes.The tested electric current of the primary side major loop of hall device will generate magnetic flux, caused by the electric current passed through by secondary side bucking coil
Magnetic keeps magnetic balance state, the hall device then effect always in detection Zero flux, so referred to as Hall magnetic after compensating
Compensate current sensor.This advanced principle modes are in response to the time fastly and survey better than straight inspection principle modes, prominent advantage
Accuracy of measurement is high, the detection especially suitable for small and weak electric current.
It is connected with the conductor in magnetic field when charge flows through, since the effect of Lorentz force can be collected at conductor upper and lower surface, is generated
Electric field.And in upper bottom crown, electric field can be also induced, potential difference is induced, being embodied in output end is exactly to follow input current
Output voltage Vs, Vs=sensitivity (mV/A) the * Ipn+Vref of Ipn.Output voltage Vs follows input current Ipn, is a reality
The analog quantity of Shi Bianhua, it is easy to be interfered by extraneous electromagnetic signal, lead to Vs output distortion, such as Fig. 4.
In order to solve the problems, such as that Hall current sensor output is asked vulnerable to interference and current sampling circuit common mode interference
Topic.The application uses two opposite polarity Hall current sensors, and the electric current that sensor acquires is done Differential Input, so that altogether
Mould interference offsets, and realizes output waveform fidelity.
It is measured using opposite polarity two sensors, measured value is respectively as follows:
Vs1 (t)=V1 (t)+Vref+ Δ Vss (t)
Vs2 (t)=- V2 (t)+Vref+ Δ Vss (t)
As shown in figure 5, the Hall current sensor due to using same model, and the same current signal sampled, institute
With V1 (t)=V2 (t)=V (t).
Differential Input is done into the output of two Hall current sensors, then final output valve is Vs (t)=Vs1 (t)-
Vs2 (t)=V1 (t)+V2 (t)=2V (t)
At this time as can be seen that common mode interference signal Δ Vss (t) has been eliminated, finally obtained result be exactly accurately with
1/2 processing is done with Vs (t) signal of 2*Ipn electric current, then by Vs (t), obtains the sensor output waveform for following input current Ipn
Vs(t)。
Above-mentioned current sampling circuit, current acquisition component 110 sample bus to be measured to obtain sample rate current, processor
120 pairs of sample rate currents carry out difference processing and obtain the current sample result of bus to be measured.By being carried out to the electric current collected
Difference processing enables to common mode interference to offset, and realizes output waveform fidelity, improves current sample reliability.
In one embodiment, a kind of current sample method, the current sample suitable for frequency converter are provided.Such as Fig. 6 institute
Show, method includes the following steps:
Step S110: reception is set to the sampling that the current acquisition component of bus to be measured samples bus to be measured
Electric current.
Specifically, the sample rate current that current acquisition component samples bus to be measured can be received by processor.
Wherein, current acquisition component carries out current sample to bus to be measured, generates two-way sample rate current and is sent to processor.
Step S120: difference processing is carried out to sample rate current and obtains the current sample result of bus to be measured.
Accordingly, processor carries out difference processing to two-way sample rate current, so that common mode interference offsets, reduces external letter
Output waveform fidelity is realized in interference number to current sample.
Specifically, the specific device of current acquisition component and structure be not unique, need to only meet acquisition two-way sample rate current
Difference processing is carried out for processor.In one embodiment, current acquisition component includes be connected to bus to be measured first
The polarity of current sensor and the second current sensor, the first current sensor and the second current sensor is opposite.Step S120
Include: the sample rate current that exports the first current sensor and the second current sensor respectively as Differential Input, two-way is adopted
Sample electric current is handled to obtain the current sample result of bus to be measured.
Two opposite polarity two current sensors are attempted by bus to be measured, electric current is carried out to bus to be measured respectively
Sampling, output sample rate current to processor carry out difference processing.Wherein, processor passes the first current sensor and the second electric current
The two-way sample rate current of sensor output is used as Differential Input, obtaining the result is that twice of virtual voltage, therefore processor general
To result do 1/2 processing, obtain the current sample result of bus to be measured.
The concrete type of first current sensor and the second current sensor be not yet it is unique, in the present embodiment, the
One current sensor and the second current sensor are Hall current sensor.Electric current is carried out using Hall current sensor to adopt
Sample, response is fast and can realize the electrical isolation of current sample, easy to operate reliable.
In one embodiment, as shown in fig. 7, after step S120, this method may also include step S130.
Step S130: output current sample result.Specifically, processor obtains current sample result in progress difference processing
Afterwards, it can be and current sample result be sent to peripheral control unit, so that outside control is controlled according to current sample result,
Or current sample result is exported to display and is shown, improve current acquisition operation ease.
Above-mentioned current sample method, current acquisition component are sampled to obtain sample rate current to bus to be measured, to sampling electricity
Stream carries out difference processing and obtains the current sample result of bus to be measured.By carrying out difference processing, energy to the electric current collected
Enough so that common mode interference offsets, realizes output waveform fidelity, improve current sample reliability.
In one embodiment, a kind of air conditioning frequency converter, including above-mentioned current sampling circuit are additionally provided.Specifically, empty
Frequency converter is adjusted to may also include converter unit and controller, controller connects the processor in converter unit and current sampling circuit,
Controller carries out frequency control to converter unit according to the current sample result that processor exports.
Above-mentioned air conditioning frequency converter, current acquisition component is sampled to obtain sample rate current to bus to be measured, to sample rate current
It carries out difference processing and obtains the current sample result of bus to be measured.It, can by carrying out difference processing to the electric current collected
So that common mode interference offsets, realizes output waveform fidelity, improve current sample reliability.
In one embodiment, a kind of air-conditioning, including above-mentioned air conditioning frequency converter are additionally provided.
Above-mentioned air-conditioning, current acquisition component are sampled to obtain sample rate current to bus to be measured, and it is poor to carry out to sample rate current
Processing is divided to obtain the current sample result of bus to be measured.By carrying out difference processing to the electric current collected, enable to altogether
Mould interference offsets, and realizes output waveform fidelity, improves current sample reliability.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality
It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited
In contradiction, all should be considered as described in this specification.
The several embodiments of the application above described embodiment only expresses, the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, without departing from the concept of this application, various modifications and improvements can be made, these belong to the protection of the application
Range.Therefore, the scope of protection shall be subject to the appended claims for the application patent.
Claims (10)
1. a kind of current sampling circuit, which is characterized in that including current acquisition component and processor, the current acquisition component is set
It is placed in bus to be measured, the processor connects the current acquisition component,
The current acquisition component obtains sample rate current and is sent to the processing for sampling to the bus to be measured
Device, the processor carry out difference processing to the sample rate current and obtain the current sample result of the bus to be measured.
2. circuit according to claim 1, which is characterized in that the current acquisition component includes being connected to the mother to be measured
The first current sensor and the second current sensor of line, the pole of first current sensor and second current sensor
Property is on the contrary, and be all connected with the processor.
3. circuit according to claim 2, which is characterized in that first current sensor and second current sense
Device is Hall current sensor.
4. circuit according to claim 3, which is characterized in that the processor is by first current sensor and described
The sample rate current that second current sensor exports respectively as Differential Input, to two-way sample rate current handled to obtain it is described to
Survey the current sample result of bus.
5. circuit according to claim 3, which is characterized in that the processor includes the first differential input end, second poor
Dividing input terminal and output end, the output cathode of first current sensor connects the second differential input end of the processor,
The output negative pole of first current sensor is grounded, and the output negative pole of second current sensor connects the processor
First differential input end, the output cathode ground connection of second current sensor, the output end of the processor is for exporting institute
State the current sample result of bus to be measured.
6. a kind of current sample method, which comprises the following steps:
Reception is set to the sample rate current that the current acquisition component of bus to be measured samples the bus to be measured；
Difference processing is carried out to the sample rate current and obtains the current sample result of the bus to be measured.
7. according to the method described in claim 6, it is characterized in that, the current acquisition component includes being connected to the mother to be measured
The first current sensor and the second current sensor of line, the pole of first current sensor and second current sensor
Property is opposite；It is described that the current sample result of the bus to be measured is obtained to sample rate current progress difference processing, comprising:
The sample rate current that first current sensor and second current sensor are exported respectively is right as Differential Input
Two-way sample rate current is handled to obtain the current sample result of the bus to be measured.
8. according to the method described in claim 6, it is characterized in that, to the sample rate current carry out difference processing obtain it is described to
It surveys after the current sample result of bus, further includes the steps that exporting the current sample result.
9. a kind of air conditioning frequency converter, which is characterized in that including current sampling circuit described in claim 1-5 any one.
10. a kind of air-conditioning, which is characterized in that including air conditioning frequency converter as claimed in claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910136121.1A CN109696576A (en) | 2019-02-25 | 2019-02-25 | Current sampling circuit and method, air conditioner frequency converter and air conditioner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910136121.1A CN109696576A (en) | 2019-02-25 | 2019-02-25 | Current sampling circuit and method, air conditioner frequency converter and air conditioner |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201444169U (en) * | 2009-06-27 | 2010-04-28 | 邱召运 | Differential Hall unit |
| CN201514439U (en) * | 2009-10-20 | 2010-06-23 | 邱召运 | Differential Hall current sensor |
| CN203350335U (en) * | 2013-07-05 | 2013-12-18 | 华中科技大学 | Double Hall element current sensor |
| CN204807623U (en) * | 2015-07-16 | 2015-11-25 | 北京长城华冠汽车科技股份有限公司 | Acquisition circuit and contain this acquisition circuit's battery management system |
| CN105158543A (en) * | 2015-09-23 | 2015-12-16 | 厦门红相电力设备股份有限公司 | Acquisition unit for leak current of ultra high voltage direct-current arrester based on two Hall elements |
| CN109116083A (en) * | 2018-07-09 | 2019-01-01 | 贵州民族大学 | A kind of double Hall double-iron core current sensors |
-
2019
- 2019-02-25 CN CN201910136121.1A patent/CN109696576A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201444169U (en) * | 2009-06-27 | 2010-04-28 | 邱召运 | Differential Hall unit |
| CN201514439U (en) * | 2009-10-20 | 2010-06-23 | 邱召运 | Differential Hall current sensor |
| CN203350335U (en) * | 2013-07-05 | 2013-12-18 | 华中科技大学 | Double Hall element current sensor |
| CN204807623U (en) * | 2015-07-16 | 2015-11-25 | 北京长城华冠汽车科技股份有限公司 | Acquisition circuit and contain this acquisition circuit's battery management system |
| CN105158543A (en) * | 2015-09-23 | 2015-12-16 | 厦门红相电力设备股份有限公司 | Acquisition unit for leak current of ultra high voltage direct-current arrester based on two Hall elements |
| CN109116083A (en) * | 2018-07-09 | 2019-01-01 | 贵州民族大学 | A kind of double Hall double-iron core current sensors |
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