CN208969157U - A kind of DC voltage measuring device - Google Patents
A kind of DC voltage measuring device Download PDFInfo
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- CN208969157U CN208969157U CN201821419063.0U CN201821419063U CN208969157U CN 208969157 U CN208969157 U CN 208969157U CN 201821419063 U CN201821419063 U CN 201821419063U CN 208969157 U CN208969157 U CN 208969157U
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Abstract
The utility model provides a kind of DC voltage measuring device, including first voltage measurement end, second voltage measurement end, first capacitor, first diode, transformer, the second diode, electronic switch module, power supply, sampling module, measurement pulse control end；First voltage measurement end is connect with the output end of the first end of first capacitor, first diode respectively, the first end of the secondary windings of the input terminal and transformer of first diode connects, and second voltage measurement end is connect with the second end of the second end of first capacitor, the secondary windings of transformer respectively；The first end of the armature winding of transformer is connect with power supply, measurement pulse control end respectively by electronic switch module, and the first end of the armature winding of transformer is connect with the output end of the second diode, the second end of the armature winding of transformer understands with the input terminal of the second diode, sampling module respectively.The utility model can be effectively reduced the cost of DC voltage measurement, while improve the grade of isolation voltage.
Description
Technical field
The utility model relates to field of circuit technology, more particularly, to a kind of DC voltage measuring device.
Background technique
Currently, with the rapid development of power electronic technique, energy-accumulating power station, unattended operation transformer station, battery management system,
Requirement of the electric system such as fuel cell power system to electrical parameters detection is higher and higher.Especially need some to high current
In the case where with high voltage measuring and control and to surveyed electric current and the more demanding accuracy of voltage, need using a kind of installation
The measurement method of DC current and voltage convenient, safe and reliable, accuracy is high.
In the prior art, the measurement of DC voltage is mainly realized using following three kinds of modes:
First, serial analog-to-digital conversion light-coupled isolation mode, will convert cell voltage using serial analog-digital converter ADC
For digital signal, and serial data bus is transferred to by digital light-coupled isolation, is read back the battery electricity of each data channel by DSP
Pressure.The shortcomings that this mode is to need independent accessory power supply per serial ADC all the way, leads to signal conditioning circuit, digital signal
Isolation structure is complicated, and the high expensive of serial analog-digital converter ADC.
Second, linear optical coupling or digital optocoupler compensation, realize that the battery voltage of isolation detects using linear optical coupling, but
It is that cost is excessively high；And digital optocoupler is used to add compensation circuit, the shortcomings that digital optocoupler is because of input for analog signal
Output it is linear poor, and can vary with temperature it is larger, need the additional temperature drift to digital optocoupler be corrected and
It is non-linear to compensate.
Third, voltage to frequency convert light-coupled isolation, is converted into pulse chip for voltage signal using V/F device, with frequency
Mode carry out the variation of reflecting voltage, using digital optocoupler every rear by measurement frequency, corresponding direct current is calculated
Pressure.But in V/F circuit, need to reach that sufficiently high stabilization is fixed and precision, has very high requirement to the device in circuit, together
When the corresponding measurement accuracy of frequency range be extremely difficult to a satisfactory to both parties selection between cost and precision.
Utility model content
The utility model embodiment provides a kind of DC voltage measuring device, to solve existing DC voltage measurement side
Formula higher cost and the low technical problem of reliability, to be effectively reduced the cost of DC voltage measurement, while improving isolation
The grade of voltage.
In order to solve the above-mentioned technical problem, the utility model embodiment provides a kind of DC voltage measuring device, including
First voltage measurement end, second voltage measurement end, first capacitor, first diode, transformer, the second diode, electronic switch
Module, power supply, sampling module, measurement pulse control end；
The first voltage measurement end connects with the output end of the first end of the first capacitor, the first diode respectively
It connects, the input terminal of the first diode is connect with the first end of the secondary windings of the transformer, the second voltage measurement
End is connect with the second end of the second end of the first capacitor, the secondary windings of the transformer respectively；
The first end of the armature winding of the transformer by the electronic switch module respectively with the power supply, the survey
The connection of pulse control end is measured, and the first end of the armature winding of the transformer is connect with the output end of second diode,
The second end of the armature winding of the transformer is connect with the input terminal of second diode, the sampling module respectively.
Preferably, the electronic switch module includes PNP type triode, first resistor, second resistance, NPN type
Triode, 3rd resistor；
The collector of the PNP type triode primary with the output end of second diode, the transformer respectively
The first end of winding connects, and the emitter of the PNP type triode connects with the first end of the power supply, the first resistor respectively
It connecing, the base stage of the PNP type triode is connect with the first end of the second end of the first resistor, the second resistance respectively,
The second end of the second resistance is connect with the collector of the NPN type triode, and the emitter of the NPN type triode connects
The base stage on ground, the NPN type triode is connect by the 3rd resistor with the measurement pulse control end.
Preferably, the DC voltage measuring device further includes the 4th resistance, the 5th resistance, the 6th resistance；
The first end of 4th resistance is connect with the first voltage measurement end, the second end difference of the 4th resistance
It is connect with the output end of the first diode, the first end of the first capacitor, the first end of the 5th resistance, described
Five resistor coupled in parallel are connected in the first end and second end of the first capacitor, the first end and described second of the 6th resistance
Voltage measuring terminal connection, the second end of the 6th resistance respectively with the second end of the transformer secondary output winding, described first
The second end of capacitor, the connection of the second end of the 5th resistance.
Preferably, the sampling module includes the 7th resistance, the 8th resistance, the second capacitor；
The input with the first end, second diode of the 8th resistance respectively of the first end of 7th resistance
The second end connection at end, the primary winding, the second end of the 7th resistance is as sample point and with described second
The first end of capacitor connects, and the second end of the second end of second capacitor and the 8th resistance is altogether.
Compared with the prior art, the beneficial effect of the utility model embodiment is, realizes by using the transformer
The isolation of electric signal can operatively reduce the cost of DC power supply measuring circuit；
Wherein, a pulse constant pressure letter is added on the armature winding of the transformer by the measurement pulse control end
Number, the electronic switch module when measuring pulse control signal generation, return by the primary that the power supply and the transformer is connected
Road, and make the primary circuit of the transformer form exciting current in conjunction with the sampling module, while passing through the transformer
Armature winding exciting current is coupled to the secondary windings of the transformer, by being described first after the first diode
Capacitor charging；
When first capacitor charging reaches balance, under unmeasured voltage status, the voltage at the first capacitor both ends
Measured voltage between the first voltage measurement end and the second voltage measurement end in partial pressure proportionate relationship, and by this
When voltage be labeled as first voltage；
After starting to measure voltage, the induced current of the induced electrified generation of the armature winding of the transformer is transferred to described
At diode, the diode current flow, so that the first capacitor charges, the voltage at the first capacitor both ends is from original
The first voltage rise to second voltage, thus electric current rise trend transfer, pass through the primary of the transformer
The electric current of winding rises to the first electric current from 0, and then completes the measurement of DC voltage.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the DC voltage measuring device in the utility model embodiment；
Fig. 2 is the expanded application schematic diagram of the DC voltage measuring device in the utility model embodiment.
Specific embodiment
The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model
Clearly and completely describe, it is clear that the described embodiments are only a part of the embodiments of the utility model, rather than whole
Embodiment.Based on the embodiments of the present invention, those of ordinary skill in the art are without creative efforts
Every other embodiment obtained, fall within the protection scope of the utility model.
Referring to Figure 1, the utility model embodiment provides a kind of DC voltage measuring device, including first voltage U0 is surveyed
Measure end V+, second voltage U1 measurement end V-, first capacitor C1, first diode D1, transformer T1, the second diode D2, electronics
Switch module 1, power vd D, sampling module 2, measurement pulse control end；
The first voltage U0 measurement end V+ respectively with the first end of the first capacitor C1, the first diode D1
Output end connection, the input terminal of the first diode D1 is connect with the first end of the secondary windings of the transformer T1, described
Second voltage U1 measurement end V- respectively with the second end of the first capacitor C1, the secondary windings of the transformer T1 second
End connection；
The first end of the armature winding of the transformer T1 by the electronic switch module 1 respectively with the power vd D,
Measurement pulse control end connection, and the first end of the armature winding of the transformer T1 and the second diode D2's is defeated
Outlet connection, the second end of the armature winding of the transformer T1 respectively with the input terminal of the second diode D2, described take
Egf block 2 connects.
In the present embodiment, the isolation that electric signal is realized by using the transformer T1, can operatively reduce
The cost of DC power supply VDD measuring circuit；
Wherein, a pulse constant pressure is added on the armature winding of the transformer T1 by the measurement pulse control end
The power vd D and the transformer T1 is connected when measuring pulse control signal generation in signal, the electronic switch module 1
Primary circuit, and in conjunction with the sampling module 2 make the transformer T1 primary circuit formed exciting current, pass through simultaneously
Exciting current is coupled to the secondary windings of the transformer T1 by the armature winding of the transformer T1, passes through the one or two pole
It is the first capacitor C1 charging after pipe D1；
When first capacitor C1 charging reaches balance, under unmeasured voltage status, the both ends the first capacitor C1
Measured voltage between voltage and the first voltage U0 measurement end V+ and the second voltage U1 measurement end V- is in the ratio divided
Example relationship, and voltage at this time is labeled as first voltage U0；
After starting to measure voltage, the induced current of the induced electrified generation of armature winding of the transformer T1 is transferred to institute
It states at first diode D1, the first diode D1 conducting, so that the first capacitor C1 charges, the first capacitor
The voltage at the both ends C1 rises to second voltage U1 from original first voltage U0, so that the trend that electric current rises occurs to turn
Folding rises to the first electric current I1 from 0 by the electric current of the armature winding of the transformer T1, and then completes the survey of DC voltage
Amount.
In a kind of wherein embodiment, the electronic switch module 1 includes PNP type triode Q1, first resistor R1, the
Two resistance R2, NPN type triode Q2,3rd resistor R3；
The collector of the PNP type triode Q1 respectively with the output end of the second diode D2, the transformer T1
Armature winding first end connection, the emitter of the PNP type triode Q1 respectively with the power vd D, it is described first electricity
Hinder R1 first end connection, the base stage of the PNP type triode Q1 respectively with the second end of the first resistor R1, described second
The first end of resistance R2 connects, and the second end of the second resistance R2 is connect with the collector of the NPN type triode Q2, institute
The emitter ground connection of NPN type triode Q2 is stated, the base stage of the NPN type triode Q2 passes through the 3rd resistor R3 and the survey
Measure the connection of pulse control end.
In a kind of wherein embodiment, the DC voltage measuring device further includes the 4th resistance R4, the 5th resistance
R5, the 6th resistance R6；
The first end of the 4th resistance R4 is connect with the first voltage U0 measurement end V+, and the of the 4th resistance R4
Two ends respectively with the output end of the first diode D1, the first end of the first capacitor C1, the 5th resistance R5
One end connection, the 5th resistance R5 are connected in parallel in the first end and second end of the first capacitor C1, the 6th electricity
Resistance R6 first end connect with the second voltage U1 measurement end V-, the second end of the 6th resistance R6 respectively with the transformation
The second end of device T1 secondary windings, the second end of the first capacitor C1, the connection of the second end of the 5th resistance R5.
In a kind of wherein embodiment, the sampling module 2 includes the 7th resistance R7, the 8th resistance R8, the second capacitor
C2；
The first end of the 7th resistance R7 respectively with the first end of the 8th resistance R8, the second diode D2
The second end connection of input terminal, the transformer T1 armature winding, the second end of the 7th resistance R7 as sample point and with
The first end of the second capacitor C2 connects, and the second end of the second capacitor C2 and the second end of the 8th resistance R8 are total
Ground.
In the utility model embodiment, the principle of the voltage measuring apparatus is:
In order to realize the isolation of electric signal, since transformer T1 is a kind of highly developed isolating device, pass through electromagnetism
The transmitting of energy and signal is realized in coupling.
In order to realize DC voltage measurement, one is added by the measurement pulse control end in the primary of the transformer T1
A pulse constant voltage signal, and in the primary circuit of the transformer T1, the 8th resistance for sampling of connecting
R8。
By the first diode D1, the second diode D2, the first resistor R1, the second resistance R2,
The 3rd resistor R3 forms the electronic switch module 1；
When there is measurement control pulse to generate, the second diode D2 conducting triggers the first diode D1 conducting,
The power vd D is formed into a loop over the ground by the primary of the transformer T1, the 8th resistance R8, and the transformer T1 is primary
Form exciting current.Secondary is coupled to by the transformer T1 simultaneously, by after the diode to the first capacitor C1
Charging.
When the induced voltage that the transformer T1 is generated is lower than the both ends of the first capacitor C1, second diode
D2 does not have electric current to pass through, and the transformer T1 coil both end voltage is from 0 rapid increase.
When voltage rises to the first capacitor C1 and after making the second diode D2 conducting voltage, to described
One capacitor C1 charging, so as to there is electric current to flow through in the second diode D2.
Due to the principle that the electromagnetic induction of the transformer T1 couples, in the primary and secondary of the transformer T1, voltage
It is directly related with transformer T1 physical characteristic with the variation characteristic of electric current.
In the secondary of the transformer T1, pass through the 4th resistance R4, the 5th resistance R5, the 6th resistance R6 and tested electricity
Pressure connection constitutes a bleeder circuit, and the first capacitor C1 charging reaches balance, under unmeasured state, first electricity
Hold C1 both end voltage and measured voltage is in the proportionate relationship of electric resistance partial pressure, voltage at this time is labeled as U0.
After starting measurement, the transformer T1 primary is powered the induced current generated, on the electric current is rapid since 0 ing
Rise, when the first diode D1 is connected, after first capacitor C1 charging, the voltage at the both ends the first capacitor C1 from
U0 rises to U1, and the trend that electric current rises is transferred, and rises to I1 from 0 by the electric current of the transformer T1 primary.
After measuring end-of-pulsing, the first capacitor C1 discharges to the 5th resistance R5, is restored to U0.
The position the 8th resistance R8 of the transformer T1 primary, obtains the same trend of curent change, and have
The voltage signal of linear ratio relation, the subsequent circuit provided after RC is filtered are further processed.Turned using AD
It changes, and corrects diode drop with hop algorithm, the transformer T1 internal resistance influences, and capacitor charging influences etc., it is converted by comprehensive
It obtains measurement and obtains voltage U0.
Fig. 2 is referred to, in the utility model embodiment, can be extended on the basis of DC voltage measuring device more
The voltage isolation measurement on road,
It should be understood that switch S1 can be realized in practice by triode, metal-oxide-semiconductor or analog switch, for controlling
System measurement pulse, to realize the selection and measurement in channel by the measurement pulse signal for controlling different channels.
To sum up, the utility model embodiment provides a kind of DC voltage measuring device, including first voltage U0 measurement end V
+, second voltage U1 measurement end V-, first capacitor C1, first diode D1, transformer T1, the second diode D2, electronic switch mould
Block 1, power vd D, sampling module 2, measurement pulse control end；The first voltage U0 measurement end V+ respectively with the first capacitor
The output end connection of the first end of C1, the first diode D1, the input terminal and the transformer of the first diode D1
The first end of the secondary windings of T1 connects, the second voltage U1 measurement end V- respectively with the second end of the first capacitor C1,
The second end of the secondary windings of the transformer T1 connects；The first end of the armature winding of the transformer T1 passes through the electronics
Switch module 1 is connect with the power vd D, the measurement pulse control end respectively, and the armature winding of the transformer T1
First end is connect with the output end of the second diode D2, the second end of the armature winding of the transformer T1 respectively with it is described
Input terminal, the sampling module 2 of second diode D2 connects.
Compared with the prior art, the utility model embodiment has the following beneficial effects:
(1) isolation that electric signal is realized by using the transformer T1, can operatively reduce DC power supply VDD
The cost of measuring circuit；
(2) a pulse constant pressure letter is added on the armature winding of the transformer T1 by the measurement pulse control end
Number, the electronic switch module 1 is connected the power vd D's and transformer T1 when measuring pulse control signal generation
Primary circuit, and make the primary circuit of the transformer T1 form exciting current in conjunction with the sampling module 2, while passing through institute
Exciting current is coupled to the secondary windings of the transformer T1 by the armature winding for stating transformer T1, passes through the first diode
It is the first capacitor C1 charging after D1；
(3) when first capacitor C1 charging reaches balance, under unmeasured voltage status, the both ends the first capacitor C1
Voltage and the first voltage U0 measurement end V+ and the second voltage U1 measurement end V- between measured voltage in partial pressure
Proportionate relationship, and voltage at this time is labeled as first voltage U0；
After starting to measure voltage, the induced current of the induced electrified generation of armature winding of the transformer T1 is transferred to institute
It states at first diode D1, the first diode D1 conducting, so that the first capacitor C1 charges, the first capacitor
The voltage at the both ends C1 rises to second voltage U1 from original first voltage U0, so that the trend that electric current rises occurs to turn
Folding rises to the first electric current I1 from 0 by the electric current of the armature winding of the transformer T1, and then completes the survey of DC voltage
Amount.
Since transformer has highly developed processing technology, it is easy to realize high-grade isolation voltage.Transformer is
Mechanical action is not present in static magnetic induction part, has lasting reliability.Pulse transformer is easily achieved the automatic of batch
Change processing, and material is conventional material, has good cost effect.It is sampled, is had preferably anti-with current system by resistance
Interference performance, while the ratio of precision transformer inductance of resistance is easier to ensure precision.
The above is preferred embodiments of the present invention, it is noted that for the ordinary skill of the art
For personnel, without departing from the principle of this utility model, several improvements and modifications can also be made, these are improved and profit
Decorations are also considered as the protection scope of the utility model.
Claims (4)
1. a kind of DC voltage measuring device, which is characterized in that including first voltage measurement end, second voltage measurement end, first
Capacitor, first diode, transformer, the second diode, electronic switch module, power supply, sampling module, measurement pulse control end；
The first voltage measurement end is connect with the output end of the first end of the first capacitor, the first diode respectively,
The input terminal of the first diode is connect with the first end of the secondary windings of the transformer, the second voltage measurement end point
It is not connect with the second end of the second end of the first capacitor, the secondary windings of the transformer；
The first end of the armature winding of the transformer by the electronic switch module respectively with the power supply, the measurement arteries and veins
Control terminal connection is rushed, and the first end of the armature winding of the transformer is connect with the output end of second diode, it is described
The second end of the armature winding of transformer is connect with the input terminal of second diode, the sampling module respectively.
2. DC voltage measuring device as described in claim 1, which is characterized in that the electronic switch module includes positive-negative-positive
Triode, first resistor, second resistance, NPN type triode, 3rd resistor；
The collector of the PNP type triode armature winding with the output end of second diode, the transformer respectively
First end connection, the emitter of the PNP type triode connect with the first end of the power supply, the first resistor respectively,
The base stage of the PNP type triode is connect with the first end of the second end of the first resistor, the second resistance respectively, described
The second end of second resistance is connect with the collector of the NPN type triode, the emitter ground connection of the NPN type triode, institute
The base stage for stating NPN type triode is connect by the 3rd resistor with the measurement pulse control end.
3. DC voltage measuring device as described in claim 1, which is characterized in that the DC voltage measuring device further includes
4th resistance, the 5th resistance, the 6th resistance；
The first end of 4th resistance is connect with the first voltage measurement end, the second end of the 4th resistance respectively with institute
State the output end of first diode, the first end of the first capacitor, the connection of the first end of the 5th resistance, the 5th electricity
Resistance is connected in parallel in the first end and second end of the first capacitor, the first end and the second voltage of the 6th resistance
Measurement end connection, the second end of the 6th resistance respectively with the second end of the transformer secondary output winding, the first capacitor
Second end, the second end of the 5th resistance connection.
4. DC voltage measuring device as described in claim 1, which is characterized in that the sampling module include the 7th resistance,
8th resistance, the second capacitor；
The first end of 7th resistance respectively with the first end of the 8th resistance, the input terminal of second diode, institute
State the second end connection of primary winding, the second end of the 7th resistance as sample point and with second capacitor
The second end of first end connection, the second end of second capacitor and the 8th resistance is altogether.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821419063.0U CN208969157U (en) | 2018-08-30 | 2018-08-30 | A kind of DC voltage measuring device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821419063.0U CN208969157U (en) | 2018-08-30 | 2018-08-30 | A kind of DC voltage measuring device |
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| CN208969157U true CN208969157U (en) | 2019-06-11 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109085409A (en) * | 2018-08-30 | 2018-12-25 | 广州市竣达智能软件技术有限公司 | A kind of DC voltage measuring device |
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- 2018-08-30 CN CN201821419063.0U patent/CN208969157U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109085409A (en) * | 2018-08-30 | 2018-12-25 | 广州市竣达智能软件技术有限公司 | A kind of DC voltage measuring device |
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Address after: Room 902-7 and 902-8, No. 9, caipin Road, Huangpu District, Guangzhou, Guangdong Province Patentee after: Guangzhou Junda Intelligent Software Technology Co., Ltd. Address before: 510000 Colorful Frequency Road No. 9 902G, 902H, Guangzhou High-tech Industrial Development Zone, Guangdong Province Patentee before: Guangzhou Junda Intelligent Software Technology Co., Ltd. |