CN108508256A - Instantaneous overvoltage harvester - Google Patents
Instantaneous overvoltage harvester Download PDFInfo
- Publication number
- CN108508256A CN108508256A CN201710104175.0A CN201710104175A CN108508256A CN 108508256 A CN108508256 A CN 108508256A CN 201710104175 A CN201710104175 A CN 201710104175A CN 108508256 A CN108508256 A CN 108508256A
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- Prior art keywords
- resistance
- oxide
- metal
- semiconductor
- overvoltage
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- 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
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16528—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values using digital techniques or performing arithmetic operations
Abstract
The invention discloses a kind of instantaneous overvoltage harvesters, including operation amplifier unit, information logging modle, filter circuit, analog-digital converter, synchronous DRAM, pci interface, FPGA, clock chip, display screen and power supply；Analog-digital converter includes operational amplifier, comparator, clock circuit, digital decimation filter, first resistor, second resistance, 3rd resistor, the 4th resistance, the 5th resistance, the first capacitance, the second capacitance, the first metal-oxide-semiconductor and the second metal-oxide-semiconductor, the drain electrode of first metal-oxide-semiconductor connects power positive end by first resistor, the source electrode of first metal-oxide-semiconductor is grounded by second resistance, the source electrode of second metal-oxide-semiconductor is also connected by the noninverting input of the 5th resistance and operational amplifier, and the drain electrode of the second metal-oxide-semiconductor connects power supply negative terminal by 3rd resistor.The present invention can restore overvoltage generation situation, can be provided for power fault detection analyze foundation, circuit safety and reliability it is higher.
Description
Technical field
The present invention relates to voltage collecting device field, more particularly to a kind of instantaneous overvoltage harvester.
Background technology
Transition effect is shown as from a stable state excessively to another state.Hyper-Voltage of Power Systems is electric power
System occur under given conditions be more than normal working voltage the raised transition effect of abnormal voltage, with regard to its basic production
It takes root for source, exterior overvoltage and internal overvoltage can be divided into.Exterior overvoltage is also known as lightning surge or air is excessively electric
Pressure.Internal overvoltage be by electric system inside energy conversion or transmit caused by.The generation of Hyper-Voltage of Power Systems be with
Machine, and inside and outside overvoltage have the characteristics that it is different：Interior overvoltage frequency spectrum is very wide, usually from tens hertz to several kHz,
Exterior overvoltage wave head is steeper, and amplitude is very high.Therefore, when inside and outside overvoltage acquires simultaneously, it is susceptible to the loss of data,
It must be subject to control appropriate, the precision of sampling could be improved on the basis of not influencing picking rate.Existing voltage acquisition
Device is only capable of acquisition overvoltage, and cannot restore the situation of overvoltage generation, is thus not easy to divide power grid quality
Analysis, to which analysis foundation cannot be provided for power fault detection.Existing voltage collecting device due to lacking circuit protection function,
Its safety and reliability is relatively low.
Invention content
The technical problem to be solved in the present invention is, for the drawbacks described above of the prior art, providing a kind of can restore
Voltage generate situation, can be provided for power fault detection analysis foundation, circuit safety and reliability it is higher instantaneously it is excessively electric
Press harvester.
The technical solution adopted by the present invention to solve the technical problems is：A kind of instantaneous overvoltage harvester is constructed, is wrapped
Include operation amplifier unit, information logging modle, filter circuit, analog-digital converter, synchronous DRAM, pci interface,
FPGA, clock chip, display screen and power supply, the operation amplifier unit put the original overvoltage signal of reception
Greatly, and amplified overvoltage signal is sent to the filter circuit to be filtered, the filter circuit is by filtered mistake
Voltage signal is sent to the analog-digital converter and is converted to digital voltage signal, sequential of the analog-digital converter in the FPGA
The digital voltage signal is sequentially stored in the synchronous DRAM under control, when the synchronous dynamic random
After digital voltage signal in memory reaches half-full state, the FPGA generates interruption to the synchronous DRAM
Signal, the digital voltage signal is transmitted to computer by the synchronous DRAM by the pci interface, described
Information logging modle record over-voltage waveform, amplitude and the time of overvoltage generation simultaneously send it to the FPGA, described
FPGA restores the situation of overvoltage generation after being analyzed, the display screen is connect with the FPGA, for showing the number
The waveform of word voltage signal, the clock chip connect with the FPGA, for providing clock, the power supply respectively with institute
State operation amplifier unit, filter circuit is connected with FPGA, for powering for the instantaneous overvoltage harvester；
The analog-digital converter include operational amplifier, comparator, clock circuit, digital decimation filter, first resistor,
Second resistance, 3rd resistor, the 4th resistance, the 5th resistance, the first capacitance, the second capacitance, the first metal-oxide-semiconductor and the second metal-oxide-semiconductor, institute
The drain electrode for stating the first metal-oxide-semiconductor connects power positive end by the first resistor, and the source electrode of first metal-oxide-semiconductor passes through described second
The source electrode of resistance eutral grounding, second metal-oxide-semiconductor is also connected by the noninverting input of the 5th resistance and the operational amplifier
It connects, the drain electrode of second metal-oxide-semiconductor connects power supply negative terminal by the 3rd resistor, and the source electrode of second metal-oxide-semiconductor passes through institute
State the 4th resistance connection reference power source end or ground connection, the anti-phase input of the source electrode and the operational amplifier of second metal-oxide-semiconductor
End connection, the noninverting input of the operational amplifier are also connect by first capacitance with its output end, and the operation is put
The output end of big device is connect by second capacitance with the input terminal of the comparator, the output end of the comparator with it is described
Digital decimation filter connects, and the output end of the comparator is also connected with reference power source end or ground connection, and the comparator is also connected with
The clock circuit.
In instantaneous overvoltage harvester of the present invention, the analog-digital converter further includes the 6th resistance, described
The source electrode of second metal-oxide-semiconductor is connect by the 6th resistance with the inverting input of the operational amplifier.
In instantaneous overvoltage harvester of the present invention, the analog-digital converter further includes third capacitance, described
The output end of comparator is connect by the third capacitance with the digital decimation filter.
In instantaneous overvoltage harvester of the present invention, the analog-digital converter further includes the 7th resistance, described
7th resistance is in parallel with first capacitance.
In instantaneous overvoltage harvester of the present invention, the analog-digital converter further includes the 8th resistance, described
One end of 8th resistance connects the reference power source end or ground connection, and the other end and the digital decimation of the 8th resistance filter
Device connects.
In instantaneous overvoltage harvester of the present invention, the analog-digital converter further includes the 9th resistance, described
Comparator also connects the clock circuit by the 9th resistance.
The instantaneous overvoltage harvester for implementing the present invention, has the advantages that：Due to be equipped with operation amplifier unit,
Information logging modle, analog-digital converter, synchronous DRAM, pci interface, FPGA, clock chip, is shown filter circuit
Display screen and power supply, the instantaneous overvoltage harvester acquire overvoltage in real time, record over-voltage waveform, amplitude and
The time that overvoltage occurs restores the situation of overvoltage generation, and the analysis and power fault detection to power grid quality, which provide, to divide
Foundation is analysed, analog-digital converter includes operational amplifier, comparator, clock circuit, digital decimation filter, first resistor, second
Resistance, 3rd resistor, the 4th resistance, the 5th resistance, the first capacitance, the second capacitance, the first metal-oxide-semiconductor and the second metal-oxide-semiconductor, the 5th electricity
Resistance is for carrying out overcurrent protection, and the second capacitance is used to prevent the interference between operational amplifier and comparator, therefore it can be restored
Go out overvoltage generation situation, can be provided for power fault detection analyze foundation, circuit safety and reliability it is higher.
Description of the drawings
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 technology 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 having to pay creative labor, may be used also for those of ordinary skill in the art
With obtain other attached drawings according to these attached drawings.
Fig. 1 is the structural schematic diagram in instantaneous overvoltage harvester one embodiment of the present invention；
Fig. 2 is the circuit diagram of analog-digital converter in the embodiment.
Specific implementation mode
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 describes, 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.
In instantaneous overvoltage harvester embodiment of the present invention, the structural schematic diagram of the instantaneous overvoltage harvester is such as
Shown in Fig. 1.In Fig. 1, the instantaneous overvoltage harvester include operation amplifier unit 1, information logging modle 2, filter circuit 3,
Analog-digital converter 4, synchronous DRAM 5, pci interface 6, FPGA7, clock chip 8, display screen 9 and power supply 10,
Wherein, operation amplifier unit 1 is amplified the original overvoltage signal of reception, and amplified overvoltage signal is sent to
Filter circuit 3 is filtered, and filtered overvoltage signal is sent to analog-digital converter 4 and is converted to digital electricity by filter circuit 3
Signal, analog-digital converter 4 is pressed sequentially to store digital voltage signal to synchronous dynamic random under the timing control of FPGA7 and store
In device 5.
After the digital voltage signal in synchronous DRAM 5 reaches half-full state, FPGA7 to synchronous dynamic with
Machine memory 5 generates interrupt signal, and digital voltage signal is transmitted to calculating by synchronous DRAM 5 by pci interface 6
Machine, information logging modle 2 record the time that over-voltage waveform, amplitude and overvoltage occur and send it to FPGA7, FPGA7
The situation of overvoltage generation is restored after analyzing it, display screen 9 is connect with FPGA7, for showing digital voltage signal
Waveform, clock chip 8 connect with FPGA7, for providing clock, power supply 10 respectively with operation amplifier unit 1, filtered electrical
Road 3 is connected with FPGA7, for powering for the instantaneous overvoltage harvester.In the present embodiment, the model of the selection of fpga chip 7
For XC3S400AN；The model DS1302 that clock chip 8 is selected.
The present invention is by the timing control of FPGA7, filtered overvoltage signal is transformed through analog-digital converter 4
Digital voltage signal, in storage to synchronous DRAM 5, and the data in synchronous DRAM 5 reach
After half-full state, interrupt signal is generated by FPGA7, digital voltage signal is transmitted to computer by pci interface 6, is ensureing to adopt
On the basis of collecting rate, a higher sampling precision is obtained, to when taking into account inside and outside overvoltage acquisition, avoid the occurrence of number
According to loss, transmit delay etc. mistakes.
Fig. 2 is the circuit diagram of analog-digital converter in the present embodiment.In Fig. 2, which includes operation amplifier
Device A1, comparator A2, clock circuit, digital decimation filter, first resistor R1, second resistance R2,3rd resistor R3, the 4th electricity
Hinder R4, the 5th resistance R5, the first capacitance C1, the second capacitance C2, the first metal-oxide-semiconductor Q1 and the second metal-oxide-semiconductor Q2, wherein the first metal-oxide-semiconductor
The drain electrode of Q1 is grounded by first resistor R1 connection power positive ends VI+, the source electrode of the first metal-oxide-semiconductor Q1 by second resistance R2.
The source electrode of second metal-oxide-semiconductor Q2 is also connect by the 5th resistance R5 with the noninverting input of operational amplifier A 1, and second
The drain electrode of metal-oxide-semiconductor Q2 is connected by the source electrode of 3rd resistor R3 connection power supply negative terminals VI-, the second metal-oxide-semiconductor Q2 by the 4th resistance R4
Reference power source end VREF or ground connection are connect, the source electrode of the second metal-oxide-semiconductor Q2 is connect with the inverting input of operational amplifier A 1, and operation is put
The noninverting input of big device A1 is also connect by the first capacitance C1 with its output end, and the output end of operational amplifier A 1 passes through second
Capacitance C2 is connect with the input terminal of comparator A2, and the output end of comparator A2 is connect with digital decimation filter, comparator A2's
Output end is also connected with reference power source end VREF or ground connection, and comparator A2 is also connected with clock circuit.
Wherein, the 5th resistance R5 be current-limiting resistance, for the branch where the noninverting input of operational amplifier A 1 into
Row overcurrent protection, the second capacitance C2 is coupled capacitor, for preventing the interference between operational amplifier A 1 and comparator A2.The hair
The overvoltage of the bright three-phase system instantaneously occurred for electric system was recorded by being acquired in real time to original overvoltage
The time that voltage waveform, amplitude and overvoltage occur restores the situation of overvoltage generation, the analysis to power grid quality and electric power
Fault diagnosis provides analysis foundation.Therefore it can restore the situation of overvoltage generation, can provide analysis for power fault detection
Foundation, circuit safety and reliability are higher.
In the present embodiment, which further includes the 6th resistance R6, and the source electrode of the second metal-oxide-semiconductor Q2 passes through the 6th electricity
Resistance R6 is connect with the inverting input of operational amplifier A 1.6th resistance R6 is current-limiting resistance, for operational amplifier A 1
Branch where inverting input carries out overcurrent protection, to further enhance the safety and reliability of circuit.
In the present embodiment, which further includes third capacitance C3, and the output end of comparator A2 passes through third capacitance
C3 is connect with digital decimation filter.Third capacitance C3 is coupled capacitor, for preventing comparator A2 and digital decimation filter
Between interference, further to enhance the safety and reliability of circuit.
In the present embodiment, which further includes the 7th resistance R7, and the 7th resistance R7 is in parallel with the first capacitance C1.
7th resistance R7 and the first capacitance C1 form RC filter circuits.
In the present embodiment, which further includes the 8th resistance R8, and one end of the 8th resistance R8 connects reference power source
End VREF or ground connection, the other end of the 8th resistance R8 are connect with digital decimation filter.8th resistance R8 is current-limiting resistance, is used for
Overcurrent protection is carried out to the branch where the output end of comparator A2.
In the present embodiment, which further includes the 9th resistance R9, and comparator A2 also passes through the 9th resistance R9 connections
Clock circuit.9th resistance R9 is current-limiting resistance, and overcurrent protection is carried out for the branch between comparator A2 and clock circuit.
In the present embodiment, each acquisition channel only uses the first metal-oxide-semiconductor Q1, the second metal-oxide-semiconductor Q2 is alternatively switched.First
Resistance R1 and 3rd resistor R3 is connected to operational amplifier A 1, and is connected to second resistance R2 and the 4th resistance by selecting switch
R4；Operational amplifier A 1 and the first capacitance C1 form active integrating circuit.Because the node voltage after partial pressure has been reduced to low
Pressure, so nothing is subjected to high pressure between the grid and source electrode of the first metal-oxide-semiconductor Q1, the second metal-oxide-semiconductor Q2.Even if power positive end VI+/electricity
Source negative terminal VI- because of the very high voltage of unexpected control source, the first metal-oxide-semiconductor Q1, the second metal-oxide-semiconductor Q2 drain voltage can be with
Raising, but source electrode can only be increased to grid terminal voltage-Vth (Vth be metal-oxide-semiconductor threshold voltage), therefore without over-pressed risk.
In the present embodiment, the difference output of active integrator circuit is admitted to comparator A2, and comparator A2 can be when each
The clock period is once compared, and latches 0 or 1 comparison result.According to the 1 digit word output signal of comparator A2, if 1,
Then the 4th resistance R4 is connected to reference power source end VREF in next clock cycle, and if 0, then the 4th resistance R4 is in the next period
It is connected to ground.Analog to digital-analog feedback in this way, entire loop constitute a continuous time sigma-delta tune
Device processed.And one bit digital signal be admitted to digital decimation filter it is down-sampled after can be obtained by high-resolution numeral output.
In short, the instantaneous overvoltage harvester acquires overvoltage in real time, record over-voltage waveform, amplitude and mistake
The time that voltage occurs restores the situation of overvoltage generation, and the analysis and power fault detection to power grid quality provide analysis
Foundation was equipped with leakage resistance and coupled capacitor in analog-digital converter 4, therefore it can restore the situation of overvoltage generation, can be
It is higher that power fault detection provides analysis foundation, circuit safety and reliability.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
With within principle, any modification, equivalent replacement, improvement and so on should all be included in the protection scope of the present invention god.
Claims (6)
1. a kind of instantaneous overvoltage harvester, which is characterized in that including operation amplifier unit, information logging modle, filtered electrical
Road, analog-digital converter, synchronous DRAM, pci interface, FPGA, clock chip, display screen and power supply, it is described
Operation amplifier unit is amplified the original overvoltage signal of reception, and amplified overvoltage signal is sent to the filter
Wave circuit is filtered, and filtered overvoltage signal is sent to the analog-digital converter and is converted to number by the filter circuit
Voltage signal, the analog-digital converter sequentially store the digital voltage signal under the timing control of the FPGA to described
In synchronous DRAM, after the digital voltage signal in the synchronous DRAM reaches half-full state,
The FPGA generates interrupt signal to the synchronous DRAM, and the synchronous DRAM is by the number
Voltage signal is transmitted to computer by the pci interface, and described information logging modle records over-voltage waveform, amplitude and excessively electric
The time of pressure life simultaneously sends it to the FPGA, and the FPGA restores the situation of overvoltage generation, institute after being analyzed
State display screen connect with the FPGA, the waveform for showing the digital voltage signal, the clock chip and the FPGA
It connects, for providing clock, the power supply connect with the operation amplifier unit, filter circuit and FPGA, is used for respectively
It powers for the instantaneous overvoltage harvester；
The analog-digital converter includes operational amplifier, comparator, clock circuit, digital decimation filter, first resistor, second
Resistance, 3rd resistor, the 4th resistance, the 5th resistance, the first capacitance, the second capacitance, the first metal-oxide-semiconductor and the second metal-oxide-semiconductor, described
The drain electrode of one metal-oxide-semiconductor connects power positive end by the first resistor, and the source electrode of first metal-oxide-semiconductor passes through the second resistance
Ground connection, the source electrode of second metal-oxide-semiconductor are also connect by the 5th resistance with the noninverting input of the operational amplifier, institute
The drain electrode for stating the second metal-oxide-semiconductor connects power supply negative terminal by the 3rd resistor, and the source electrode of second metal-oxide-semiconductor passes through the described 4th
Resistance connects reference power source end or ground connection, the source electrode of second metal-oxide-semiconductor are connect with the inverting input of the operational amplifier,
The noninverting input of the operational amplifier is also connect by first capacitance with its output end, the operational amplifier it is defeated
Outlet is connect by second capacitance with the input terminal of the comparator, the output end of the comparator and the digital decimation
Filter connects, and the output end of the comparator is also connected with reference power source end or ground connection, and the comparator is also connected with the clock
Circuit.
2. instantaneous overvoltage harvester according to claim 1, which is characterized in that the analog-digital converter further includes
The source electrode of six resistance, second metal-oxide-semiconductor is connect by the 6th resistance with the inverting input of the operational amplifier.
3. instantaneous overvoltage harvester according to claim 2, which is characterized in that the analog-digital converter further includes
The output end of three capacitances, the comparator is connect by the third capacitance with the digital decimation filter.
4. the instantaneous overvoltage harvester according to claims 1 to 3 any one, which is characterized in that the modulus turns
Parallel operation further includes the 7th resistance, and the 7th resistance is in parallel with first capacitance.
5. instantaneous overvoltage harvester according to claim 3, which is characterized in that the analog-digital converter further includes
Eight resistance, one end of the 8th resistance connect the reference power source end or ground connection, the other end of the 8th resistance with it is described
Digital decimation filter connects.
6. instantaneous overvoltage harvester according to claim 5, which is characterized in that the analog-digital converter further includes
Nine resistance, the comparator also connect the clock circuit by the 9th resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710104175.0A CN108508256A (en) | 2017-02-24 | 2017-02-24 | Instantaneous overvoltage harvester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710104175.0A CN108508256A (en) | 2017-02-24 | 2017-02-24 | Instantaneous overvoltage harvester |
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| Publication Number | Publication Date |
|---|---|
| CN108508256A true CN108508256A (en) | 2018-09-07 |
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ID=63373010
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| Application Number | Title | Priority Date | Filing Date |
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| CN201710104175.0A Pending CN108508256A (en) | 2017-02-24 | 2017-02-24 | Instantaneous overvoltage harvester |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109451269A (en) * | 2018-11-05 | 2019-03-08 | 安徽奕甲文化传媒有限责任公司 | Exhibitions monitoring system |
| CN109709383A (en) * | 2019-03-14 | 2019-05-03 | 贵州电网有限责任公司 | A kind of trigger unit structure of over-voltage monitoring device |
| CN109756132A (en) * | 2019-01-28 | 2019-05-14 | 安徽智训机器人技术有限公司 | Web advertisement media system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203149029U (en) * | 2013-03-29 | 2013-08-21 | 国家电网公司 | Overvoltage data acquisition storage system |
| CN204334545U (en) * | 2014-10-31 | 2015-05-13 | 广东电网有限责任公司电力科学研究院 | High pressure analog to digital conversion circuit in battery management system |
-
2017
- 2017-02-24 CN CN201710104175.0A patent/CN108508256A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203149029U (en) * | 2013-03-29 | 2013-08-21 | 国家电网公司 | Overvoltage data acquisition storage system |
| CN204334545U (en) * | 2014-10-31 | 2015-05-13 | 广东电网有限责任公司电力科学研究院 | High pressure analog to digital conversion circuit in battery management system |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109451269A (en) * | 2018-11-05 | 2019-03-08 | 安徽奕甲文化传媒有限责任公司 | Exhibitions monitoring system |
| CN109756132A (en) * | 2019-01-28 | 2019-05-14 | 安徽智训机器人技术有限公司 | Web advertisement media system |
| CN109709383A (en) * | 2019-03-14 | 2019-05-03 | 贵州电网有限责任公司 | A kind of trigger unit structure of over-voltage monitoring device |
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