CN208636369U - A kind of voltage real-time acquisition device for CVT secondary side - Google Patents
A kind of voltage real-time acquisition device for CVT secondary side Download PDFInfo
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- CN208636369U CN208636369U CN201820804700.XU CN201820804700U CN208636369U CN 208636369 U CN208636369 U CN 208636369U CN 201820804700 U CN201820804700 U CN 201820804700U CN 208636369 U CN208636369 U CN 208636369U
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Abstract
The utility model discloses a kind of voltage real-time acquisition devices for CVT secondary side, including micro-chip processor, low-pass filter circuit, voltage changing module, analog-to-digital conversion module, level shifting circuit, the input terminal of low-pass filter circuit is electrically connected with the connecting terminal of CVT secondary side；The output end of low-pass filter circuit is electrically connected with the input terminal of voltage changing module；The output end of voltage changing module is electrically connected with the input terminal of level shifting circuit；The output end of level shifting circuit is electrically connected with the input terminal of analog-to-digital conversion module；The output end of analog-to-digital conversion module is electrically connected with the first input end of micro-chip processor.The utility model is not under the premise of influencing power grid running, the voltage condition of real-time detection and analysis CVT secondary side, the synchronous information of voltage and analysis of saving is as a result, ensured the safety of CVT equipment simultaneously, by the way that level shifting circuit is arranged, effectively reduce hardware cost and handles the complexity of data.
Description
Technical field
The utility model relates to CVT monitoring fields, adopt in real time more particularly, to a kind of voltage for CVT secondary side
Acquisition means.
Background technique
Capacitance type potential transformer (Capacitor Voltage Transformer, CVT) is widely used in electric power
It is voltage supplied measurement, power observing and controlling, automatic control, relay protection and the electric power being used as power line carrier capacitor in system
Equipment, impact strength is small, small in size, light-weight, can reliably damp ferromagnetic resonance, has excellent transient response characteristic.Electricity
Power equipment preventive trial is a kind of test that periodically has a power failure, and is an important ring in power equipment operation and maintenance work
Section.
Currently, CVT prerun mainly passes through measurement capacitor and dielectric loss can diagnose the dielectric insulation performance of CVT, capacitor is hit
Wear, oil starvation situations such as.And it can also reach this purpose actually by monitoring in real time to secondary voltage, or even pass through analysis CVT
The variation tendency of secondary voltage, moreover it is possible to find the problem of traditional prerun can not be found out.Current CVT on-line monitoring system is usually straight
The data for obtaining CVT secondary voltage from EMS Energy Management System backstage are connect, original voltage can be counted in real time at EMS system
It is mean effective value, 15 minutes primary deposit databases according to processing.So the number that can be got from EMS database is also 15 points
Clock is primary.The data of this frequency be for the steady-state analysis of CVT it is enough, also meet the basic need of test, but if
Transient state or transient affair has occurred in CVT, can not be captured by on-line monitoring system.
Utility model content
The utility model overcomes the defect of existing CVT detection, and it is real to provide a kind of new voltage for CVT secondary side
When acquisition device.The utility model effectively detects the voltage condition of CVT secondary side under the premise of not influencing power grid running, protects
The safety of CVT equipment is hindered.
In order to solve the above technical problems, the technical solution of the utility model is as follows:
A kind of voltage real-time acquisition device for CVT secondary side, including micro-chip processor, low-pass filter circuit, transformation
Module, analog-to-digital conversion module, level shifting circuit, wherein
The input terminal of the low-pass filter circuit is electrically connected with the connecting terminal of CVT secondary side；
The output end of the low-pass filter circuit is electrically connected with the input terminal of voltage changing module；
The output end of the voltage changing module is electrically connected with the input terminal of level shifting circuit；
The output end of the level shifting circuit is electrically connected with the input terminal of analog-to-digital conversion module；
The output end of the analog-to-digital conversion module is electrically connected with the first input end of micro-chip processor.
Utility model works process is as follows:
First from the secondary side collection voltages signal of CVT, after being filtered by low-pass filter circuit, pass through voltage changing module
Voltage signal (0 ~ 57V) is depressured to -1.25V ~ 1.25V or so, is then converted into single battery signal by level shifting circuit,
It is converted using analog-to-digital conversion module, obtains digital signal.Digital signal by micro-chip processor carry out analog-to-digital conversion and
Data analysis.
In the technical program, the collected sinusoidal signal of CVT secondary side is bipolar signal, instantaneous value have it is positive and negative, therefore
A/D module must select bipolarity to input model, increase hardware cost.In addition, micro-chip processor assumes responsibility for the real-time place of data
Work is transmitted in reason, storage, and bipolarity numerical value increases the complexity of calculating when entering micro-chip processor progress data processing.
In a preferred solution, the level shifting circuit includes the first operational amplifier, the second operation amplifier
Device, first resistor, second resistance, 3rd resistor, the 4th resistance, the 5th resistance, wherein
Input terminal of the one end of the first resistor as level shifting circuit, the other end of first resistor and the second fortune
Calculate the non-inverting input terminal electrical connection of amplifier；
The inverting input terminal of the second operational amplifier is electrically connected with one end of 3rd resistor；
The other end of the 3rd resistor is electrically connected with the output end of the first operational amplifier；
The output end of first operational amplifier is electrically connected with the inverting input terminal of the first operational amplifier；
The non-inverting input terminal of first operational amplifier connects bias voltage；
The inverting input terminal of the second operational amplifier is electrically connected with one end of the 4th resistance；
The other end of 4th resistance is grounded；
The non-inverting input terminal of the second operational amplifier is electrically connected with one end of second resistance；
The other end of the second resistance is electrically connected with the output end of second operational amplifier；
The output end of the second operational amplifier is electrically connected with one end of the 5th resistance, and the other end of the 5th resistance is made
For the output end of level shifting circuit.
In a preferred solution, the resistance value of the first resistor, second resistance and the 4th resistance is equal, third
The resistance value of resistance is 3 times of the resistance value of first resistor, and the voltage value of bias voltage is the peak value of voltage changing module output voltage
2 times of voltage.
(Vin-1/2 bias voltage)/R=(1/2 bias voltage-Vout)/R is realized in this preferred embodiment, R is the first electricity
The resistance value of resistance, it is only necessary to select suitable bias voltage, so that it may realize and convert unipolar signal for bipolar signal.
In a preferred solution, the voltage real-time acquisition device further includes mobile power source, charging circuit and LDO
Power supply chip, wherein
Control of the charging circuit by micro-chip processor, the output end of charging circuit and the input terminal of mobile power source
Electrical connection；
The input terminal of LDO power supply chip is electrically connected with the output end of mobile power source；
The output end of the LDO power supply chip is electrically connected with the second input terminal of micro-chip processor.
In this preferred embodiment, since there are certain relationships for the electricity of mobile power source and its output voltage, in limited model
Can be approximately considered in enclosing is linear relationship, so can be carried out according to this point by voltage of the micro-chip processor to mobile power source herein
Test, thus come judge battery capacity number.When portable power source electricity deficiency, micro-chip processor exports high level signal,
It is boosted by voltage amplifier circuit, the charging to mobile power source is realized in band motor type relay closure switch side.
In a preferred solution, the charging circuit includes voltage amplifier circuit, relay, power adaptation list
Member, wherein
Control terminal of the input terminal of the voltage amplifier circuit as charging circuit, the input terminal of voltage amplifier circuit with
First output end of micro-chip processor is electrically connected；
The output end of the voltage amplifier circuit is electrically connected with the control terminal of relay；
The switch-side of the relay is arranged between power adaptation unit and mobile power source；
The input terminal of the power adaptation unit is linked into commercial power socket；
One end of the switch-side of the output end and relay of the power adaptation unit；
Output end of the other end of the switch-side of the relay as charging circuit
In a preferred solution, the voltage real-time acquisition device further includes display module, the display mould
The input terminal of block is electrically connected with the second output terminal of micro-chip processor.
In this preferred embodiment, display module is for showing monitoring data.
In a preferred solution, the voltage real-time acquisition device further includes wireless communication module, the nothing
Line communication module is electrically connected with micro-chip processor.
In a preferred solution, the wireless communication module includes 4G communication module, the 4G communication module
Input terminal and micro-chip processor the 4th output end.
In this preferred embodiment, 4G communication module can be sent monitoring data in staff's hand in a distant place.
In a preferred solution, the wireless communication module includes WIFI module, the WIFI module it is defeated
Enter the 5th output end of end and micro-chip processor；Several CVT secondary side remote real time monitoring devices are made up of WIFI module
Local area network.
In this preferred embodiment, local area network, the monitoring number of CVT secondary side remote real time monitoring device are formed by WIFI module
According to can circulate in local area network.
In a preferred solution, the voltage real-time acquisition device further includes protective tube, wherein
One end of the protective tube is electrically connected with the input terminal of low-pass filter circuit；
The other end of the protective tube is electrically connected with the input terminal of voltage changing module.
In this preferred embodiment, protective tube ensures that CVT secondary side will not directly burn damage equipment.
In a preferred solution, the protective tube is 0.1A protective tube.
In a preferred solution, the voltage real-time acquisition device further includes GPS module, the GPS module
Output end be electrically connected with the third input terminal of micro-chip processor.
In a preferred solution, the voltage real-time acquisition device further includes shell, and the shell includes bottom
Seat, the pedestal are provided with bolt hole, and the voltage real-time acquisition device passes through bolt, the fixed setting of nuts and bolt hole
In CVT equipment.
Compared with prior art, the beneficial effect of technical solutions of the utility model is:
The utility model is not under the premise of influencing power grid running, the voltage condition of real-time detection and analysis CVT secondary side,
The synchronous information of voltage and analysis of saving is as a result, ensured the safety of CVT equipment.Meanwhile by the way that level shifting circuit is arranged, effectively
It reduces hardware cost and handles the complexity of data.
Detailed description of the invention
Fig. 1 is the module installation diagram of embodiment.
Fig. 2 is the low-pass filter circuit figure in embodiment.
Label declaration: 1. input terminals；2. output end；3. the first operational amplifier；.
Specific embodiment
The attached figures are only used for illustrative purposes and cannot be understood as limitating the patent；
In order to better illustrate this embodiment, the certain components of attached drawing have omission, zoom in or out, and do not represent actual product
Size；
To those skilled in the art, it is to be understood that certain known features and its explanation, which may be omitted, in attached drawing
's.
The technical solution of the utility model is described further with reference to the accompanying drawings and examples.
As shown in Figure 1, a kind of voltage real-time acquisition device for CVT secondary side, including low-pass filter circuit, insurance
Pipe, voltage transmitter, enhanced STM32 chip, WIFI module, 4G communication module, 8873130 lithium batteries, relay, power supply are suitable
With unit, voltage amplifier circuit, LDO power supply chip, the first TF card, analog-to-digital conversion module, level shifting circuit, the second TF card,
Shell and LCD display, wherein
The input terminal of low-pass filter circuit is electrically connected with the connecting terminal of CVT secondary side；
The output end of low-pass filter circuit is electrically connected with one end of protective tube；
The other end of protective tube is electrically connected with the input terminal of voltage transmitter；
The output end of voltage transmitter is electrically connected with the input terminal of level shifting circuit；
The output end of level shifting circuit is electrically connected with the input terminal of analog-to-digital conversion module；
The output end of analog-to-digital conversion module is electrically connected with the first input end of enhanced STM32 chip；
First output end of enhanced STM32 chip is electrically connected with the input terminal of WIFI module；
The second output terminal of enhanced STM32 chip is electrically connected with the input terminal of 4G communication module；
The third output end of enhanced STM32 chip is electrically connected with the input terminal of the first TF card；
4th output end of enhanced STM32 chip is electrically connected with the input terminal of LCD display；
5th output end of enhanced STM32 chip is electrically connected with the input terminal of the second TF card；
The input terminal of voltage amplifier circuit is electrically connected with the 6th output end of enhanced STM32 chip；
The output end of voltage amplifier circuit is electrically connected with the control terminal of relay；
The switch-side of relay is arranged between power adaptation unit and 8873130 lithium batteries；
The input terminal of power adaptation unit is linked into commercial power socket；
One end of the switch-side of the output end and relay of power adaptation unit；
The other end of the switch-side of relay is electrically connected with the input terminal of 8873130 lithium batteries；
The output end of 8873130 lithium batteries is electrically connected with the input terminal of LDO power supply chip；
The output end of LDO power supply chip is electrically connected with the second input terminal of enhanced STM32 chip.
Wherein, as shown in Fig. 2, low-pass filter circuit includes first resistor, second resistance, 3rd resistor, first capacitor,
Two capacitors, the first operational amplifier, wherein
Input terminal 1 of the one end of first resistor as low-pass filter circuit, the other end of first resistor and second resistance
One end electrical connection；
The other end of first resistor is electrically connected with one end of first capacitor；
The other end of first capacitor is electrically connected with the output end of the first operational amplifier 3；
The other end of second resistance is electrically connected with the non-inverting input terminal of the first operational amplifier 3；
The other end of second resistance is electrically connected with one end of the second capacitor；
The other end of second capacitor is grounded；
The output end of operational amplifier 3 is electrically connected with the output end inverting input terminal of the first operational amplifier 3；
The output end of operational amplifier 3 is electrically connected with one end of 3rd resistor, and the other end of 3rd resistor is as low pass filtered
The output end 2 of wave circuit.
Wherein, low-pass filter circuit, protective tube, acquisition unit, voltage transmitter, enhanced STM32 chip, WIFI mould
Block, 4G communication module, the first TF card, the second TF card are all disposed within the inside of shell, the input port setting of low-pass filter circuit
In the outside of shell；Camera and LCD display are arranged in the outside of shell.Shell includes pedestal, and pedestal is provided with bolt
Hole, by bolt, nuts and bolt hole is fixed in CVT equipment embodiment.
Wherein, level shifting circuit include second operational amplifier, third operational amplifier, the 4th resistance, the 5th resistance,
6th resistance, the 7th resistance, the 8th resistance, wherein
Input terminal of the one end of 4th resistance as level shifting circuit, the other end and third operation amplifier of the 4th resistance
The non-inverting input terminal of device is electrically connected；
The inverting input terminal of third operational amplifier is electrically connected with one end of the 6th resistance；
The other end of 6th resistance is electrically connected with the output end of second operational amplifier；
The output end of second operational amplifier is electrically connected with the inverting input terminal of second operational amplifier；
The non-inverting input terminal of second operational amplifier connects bias voltage；
The inverting input terminal of third operational amplifier is electrically connected with one end of the 7th resistance；
The other end of 7th resistance is grounded；
The non-inverting input terminal of third operational amplifier is electrically connected with one end of the 5th resistance；
The other end of 5th resistance is electrically connected with the output end of third operational amplifier；
The output end of third operational amplifier is electrically connected with one end of the 5th resistance, and the other end of the 8th resistance is as level
The output end of conversion circuit.
The present embodiment course of work:
Voltage signal (0 ~ 57V) is collected from the secondary side of CVT first, low-pass filter circuit is first passed around and is filtered,
Then decompression processing is being carried out by voltage transmitter, is then being converted into single battery signal by level shifting circuit, using
Analog-to-digital conversion module is converted, and digital signal is obtained.Digital signal carries out analog-to-digital conversion sum number by enhanced STM32 chip
According to analysis.Meanwhile sending the analysis result of enhanced STM32 chip in staff's hand by 4G communication module, LCD is aobvious
Display screen is for showing analysis result.WIFI module in the local area network that CVT is formed for carrying out data transmission.Camera acquisition
The waveform image of LCD display and the image data of CVT secondary side, staff's hand in a distant place is sent to by 4G communication module
In.If the electric current of CVT secondary side is more than the limitation of protective tube, protective tube disconnects automatically, protects equipment.For in acquisition data
Abnormal data, be stored in the first TF card every time；For the normal data in acquisition data, interruption is stored in the second TF card.Its
Secondary, when 8873130 electric quantity of lithium battery deficiency, enhanced STM32 chip exports high level signal, by voltage amplifier circuit into
Row boosting, band motor type relay closure switch side, realizes the charging to 8873130 lithium batteries.
The same or similar label correspond to the same or similar components；
The terms describing the positional relationship in the drawings are only for illustration, should not be understood as the limitation to this patent；
Obviously, the above embodiments of the present invention is merely examples for clearly illustrating the present invention, and
It is not limitations of the embodiments of the present invention.For those of ordinary skill in the art, in above description
On the basis of can also make other variations or changes in different ways.There is no need and unable to give all embodiments
Exhaustion.Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention etc., should be included in
Within the protection scope of the utility model claims.
Claims (8)
1. a kind of voltage real-time acquisition device for CVT secondary side, which is characterized in that including micro-chip processor, low-pass filtering
Circuit, voltage changing module, analog-to-digital conversion module, level shifting circuit, wherein
The input terminal of the low-pass filter circuit is electrically connected with the connecting terminal of CVT secondary side；
The output end of the low-pass filter circuit is electrically connected with the input terminal of voltage changing module；
The output end of the voltage changing module is electrically connected with the input terminal of level shifting circuit；
The output end of the level shifting circuit is electrically connected with the input terminal of analog-to-digital conversion module；
The output end of the analog-to-digital conversion module is electrically connected with the first input end of micro-chip processor；
The level shifting circuit includes the first operational amplifier, second operational amplifier, first resistor, second resistance, the
Three resistance, the 4th resistance, the 5th resistance, wherein
Input terminal of the one end of the first resistor as level shifting circuit, the other end of first resistor are put with the second operation
The non-inverting input terminal electrical connection of big device；
The inverting input terminal of the second operational amplifier is electrically connected with one end of 3rd resistor；
The other end of the 3rd resistor is electrically connected with the output end of the first operational amplifier；
The output end of first operational amplifier is electrically connected with the inverting input terminal of the first operational amplifier；
The non-inverting input terminal of first operational amplifier connects bias voltage；
The inverting input terminal of the second operational amplifier is electrically connected with one end of the 4th resistance；
The other end of 4th resistance is grounded；
The non-inverting input terminal of the second operational amplifier is electrically connected with one end of second resistance；
The other end of the second resistance is electrically connected with the output end of second operational amplifier；
The output end of the second operational amplifier is electrically connected with one end of the 5th resistance, and the other end of the 5th resistance is as electricity
The output end of flat conversion circuit；
The resistance value of the first resistor, second resistance and the 4th resistance is equal, and the resistance value of 3rd resistor is first resistor
3 times of resistance value, the voltage value of bias voltage is 2 times of the crest voltage of voltage changing module output voltage.
2. voltage real-time acquisition device according to claim 1, which is characterized in that the voltage real-time acquisition device is also
Including mobile power source, charging circuit and LDO power supply chip, wherein
Control of the charging circuit by micro-chip processor, the output end of charging circuit and the input terminal of mobile power source are electrically connected
It connects；
The input terminal of LDO power supply chip is electrically connected with the output end of mobile power source；
The output end of the LDO power supply chip is electrically connected with the second input terminal of micro-chip processor.
3. voltage real-time acquisition device according to claim 2, which is characterized in that the charging circuit includes that voltage is put
Big circuit, relay, power adaptation unit, wherein
Control terminal of the input terminal of the voltage amplifier circuit as charging circuit, the input terminal and Wei Chu of voltage amplifier circuit
Manage the first output end electrical connection of chip；
The output end of the voltage amplifier circuit is electrically connected with the control terminal of relay；
The switch-side of the relay is arranged between power adaptation unit and mobile power source；
The input terminal of the power adaptation unit is linked into commercial power socket；
One end of the switch-side of the output end and relay of the power adaptation unit；
Output end of the other end of the switch-side of the relay as charging circuit.
4. according to claim 1 to voltage real-time acquisition device described in any claim in 3, which is characterized in that described
Voltage real-time acquisition device further includes display module, the input terminal of the display module and the second output terminal of micro-chip processor
Electrical connection.
5. voltage real-time acquisition device according to claim 4, which is characterized in that the voltage real-time acquisition device is also
Including wireless communication module, the wireless communication module is electrically connected with micro-chip processor.
6. voltage real-time acquisition device according to claim 5, which is characterized in that the wireless communication module includes 4G
Communication module, the input terminal of the 4G communication module and the third output end of micro-chip processor.
7. voltage real-time acquisition device according to claim 5 or 6, which is characterized in that the wireless communication module packet
Include WIFI module, the input terminal of the WIFI module and the 4th output end of micro-chip processor；Several CVT secondary sides are long-range
Real-time monitoring device forms local area network by WIFI module.
8. according to claim 1, voltage real-time acquisition device described in 2,3,5 or 6, which is characterized in that the voltage is real-time
Acquisition device further includes protective tube, wherein
One end of the protective tube is electrically connected with the input terminal of low-pass filter circuit；
The other end of the protective tube is electrically connected with the input terminal of voltage changing module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820804700.XU CN208636369U (en) | 2018-05-28 | 2018-05-28 | A kind of voltage real-time acquisition device for CVT secondary side |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820804700.XU CN208636369U (en) | 2018-05-28 | 2018-05-28 | A kind of voltage real-time acquisition device for CVT secondary side |
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| CN208636369U true CN208636369U (en) | 2019-03-22 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110542782A (en) * | 2018-05-28 | 2019-12-06 | 广东电网有限责任公司 | voltage real-time acquisition device for CVT secondary side |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110542782A (en) * | 2018-05-28 | 2019-12-06 | 广东电网有限责任公司 | voltage real-time acquisition device for CVT secondary side |
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