CN209446699U - A kind of smart grounding conduction detecting system - Google Patents
A kind of smart grounding conduction detecting system Download PDFInfo
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- CN209446699U CN209446699U CN201821953466.3U CN201821953466U CN209446699U CN 209446699 U CN209446699 U CN 209446699U CN 201821953466 U CN201821953466 U CN 201821953466U CN 209446699 U CN209446699 U CN 209446699U
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Abstract
The utility model discloses a kind of smart grounding conduction detecting system, and the detection system of the utility model includes working power, data acquisition circuit, differential amplifier circuit, A/D conversion circuit, processor and human-machine interface module；The detection method of the utility model are as follows: first in the case where being not turned on working power, the voltage signal of the sampling resistor of tested pilot is acquired by data acquisition circuit, after differential amplifier circuit, the processing of A/D conversion circuit, the interference electric current of tested pilot is calculated by processor；It is then turned on working power, the output electric current of working power is adjusted according to the size of interference electric current, the sampling resistor of tested pilot and the voltage signal of standard divider resistance are acquired by data acquisition circuit, the conduction resistance value of tested pilot is finally calculated by processor；Obstructed or poor flow phenomenon caused by poor contact or ground line internal fault can be effectively detected out in the utility model, greatly improve the safety of power generation.
Description
Technical field
The utility model belongs to power equipment earth-continuity performance detection technical field, specifically a kind of smart grounding conducting
Detection system.
Background technique
Ground line is the indispensable tool during electric power overhaul, can unexpectedly be occurred in the equipment and route having had a power failure
Voltage or the safety for closing on guarantee staff when electrical body generates electrostatic sense, have highly important meaning in power generation
Justice.Whether the ground connection of its equipment and coupling for earth mat are reliable, and whether there is or not generation corrosion fracture, pads to corrode for ground line, ground
Line is then even more important whether there is or not being broken.Even if other indexs such as ground resistance of earth mat are all qualified, if the down conductor of equipment
Or the hair point fracture of earth mat backbone, it can still be directed at serious accident.When hanging ground line, power worker, which does not know, to be mounted
Whether the equipment on ground is grounded well, needs relevant potentiometric detection that personal equipment is caused to injure to prevent equipment virtual earth.In addition,
In the off time of the work of ground line detection twice, there is caused by external force ground line internal stranded, broken string due to operator
And the problem of being unaware of, it the dangerous hidden danger such as hurts sb.'s feelings so as to cause induced electricity.At the same time in the actual operation process, it partially connects
The end of ground wire can not be securely fixed on earthing bar due to being used for a long time, and the conductor part of ground line head contact can exist
It is difficult to the filth removed, when being grounded after the installation is completed, reality also has serious security risk not by equipment effective grounding.
Earthing or grounding means is usually embedded in underground, these conductors for constituting earthing or grounding means can generate corrosion phenomenon in the soil, this
The corrosion phenomenon occurred in kind soil belongs to electrochemical corrosion.The conductor of earthing or grounding means and equipment are drawn in China's electric system at present
Offline corrosion condition is increasingly prominent, mostly occurs in the earthing or grounding means of operation for a long time, results in the frequent generation of electric power accident.Corrosion
Under the main reason for generation, has: first is that not having in the design of grounding well in view of the material of reasonable selection conductor and section
Product, second is that not taking necessary anti-corrosion measure to earthing or grounding means conductor and equipment ground downlead.With the increasing of runing time
Add, the effective sectional area of earth conductor constantly reduces, and results in and is unable to satisfy thermostabilization demand.It can thus to work as and have power frequency
It, can be because fever and electrodynamic effect be led so that being grounded when earth short circuit current or lightning current flow through earthing or grounding means
Body or ground lead are broken, and cause first and second equipment breakdown, are brought weight huge economic loss to electric system, can also be given
Staff brings human safety issues.
To sum up earth wire self can not detect ground connection well and ground line break-make situation, plan are transformed it, if
Meter earth-continuity detection system makes it possible to self detect and warn field service personnel, and already referred to as safety urgently to be solved is asked
Topic.
The state of earth wire detection device studied at present is using ultrasonic ranging method, as mentioned in existing literature
Temporary ground wire total management system integrates ground line intelligent management, microcomputer anti-error, has standardized in line work and has hung, disconnects
The process of ground wire mainly passes through technical management means and eliminates the hidden danger that human factor causes serious accident.These methods and
Device plays certain effect in terms of being grounded anti-misoperation, but most of so-called technological means are all built upon management
On the anti-error and artificial judgement basis of system.Related rectification expense and system building expense are more expensive, and cannot keep away completely
Exempt from accident caused by human error.
Summary of the invention
The purpose of this utility model is in view of the problems of the existing technology, to provide one kind and confirm transmission of electricity from detection technique
The smart grounding conduction detecting system of the state of earth wire of route, so as to effectively avoid the generation of safety accident.
In order to achieve the above purposes, the technical solution adopted by the utility model is:
A kind of smart grounding conduction detecting system, including working power, data acquisition circuit, differential amplifier circuit, A/D turn
Change circuit, processor and human-machine interface module；The output end of the working power and the input terminal of data acquisition circuit connect, institute
The input terminal of the output end and differential amplifier circuit of stating data acquisition circuit connects, the output end and A/ of the differential amplifier circuit
The connection of D conversion circuit input terminal, the output end of the differential amplifier circuit connect with processor, the processor also respectively with people
Machine interface module, working power connection；The data acquisition circuit is arranged between the down conductor of electrical equipment to be detected,
For acquiring the voltage/current data of the connection resistance between equipment ground downlead；The differential amplifier circuit will be for that will count
It is amplified according to the collected voltage/current signals of Acquisition Circuit；The A/D conversion circuit is used to carry out amplified signal
Analog-to-digital conversion, and by the digital signal input processor after conversion；The processor handles the signal received, obtains
Resistance value between the down conductor of the electrical equipment, and obtained resistance value is showed into survey by human-machine interface module
Examination personnel.
Specifically, the data acquisition circuit includes low-frequency voltage measuring unit and low-frequency current measuring unit；It is described low
Frequency voltage/current measuring unit is used to measure the voltage/current data of resistance between the electrical equipment grounding downlead.
Specifically, the working power is numerical-control direct-current power source module, the output of the numerical-control direct-current power source module by
Manage device control；
Further, the input of the numerical-control direct-current power source module is 220V alternating current, is exported as direct current.
Specifically, the human-machine interface module includes voice alerting unit, LCD display unit and communication output unit；Institute
LCD display unit is stated for showing the resistance value of tested pilot；The voice alerting unit is used to prompt the conductance of tested pilot
General character energy；Storage is numbered for test result to be transferred to database in the communication output unit.
Specifically, the processor includes STC12C5A60S2 series monolithic.
Corresponding with said detecting system, the utility model additionally provides a kind of smart grounding turn-on detecting method, this
Utility model is based on faraday electromagnetic induction principle using pincers meter method for measuring resistance value, and excitation jaw carries out exchange to circuit and swashs
It encourages, loop current is detected by electric current jaw, so that resistance information is extracted, specifically includes the following steps:
S1, system initialization initialize the I/0 state of system, Memory Allocation space by processor；
S2 acquires the voltage signal at sampling resistor both ends between electrical equipment grounding downlead by data acquisition circuit,
Collected voltage signal input processor after the processing of differential amplifier circuit and A/D conversion circuit carries out data processing,
Obtain the interference electric current value between the electrical equipment grounding downlead；
S3 opens numerical-control direct-current power source module, the signal-to-noise ratio condition that should meet when according to the interference electric current value and detection
Carry out the output electric current of pre-adjustment numerical-control direct-current power source module；
S4 acquires sampling resistor both ends and electric conduction between electrical equipment grounding downlead by data acquisition circuit respectively
The voltage signal at both ends is hindered, and collected two voltage signals are passed through to the processing of differential amplifier circuit and A/D conversion circuit
Input processor carries out data processing afterwards, obtains the conduction resistance value between the electrical equipment grounding downlead；
S5, processor differentiate the current conduction of test point according to the conduction resistance value, and it is single that processor controls LCD display
The conduction resistance value of test point is showed the electric current of tester, control voice alerting unit prompt tester's test point by member
Test result is transferred to database and stored by conduction, control communication output unit.
Specifically, in step S2, the calculation formula of the interference electric current value are as follows: I0=U0/R0, wherein I0For interference electric current
Value, U0The voltage value at the sampling resistor both ends, R when to measure interference electric current value0For the resistance value of sampling resistor.
Specifically, in step S3, signal-to-noise ratio is not less than 60dB when the signal-to-noise ratio condition is test, according to the meter of signal-to-noise ratio
Formula is calculated to obtain:
It is finally calculated: Is≥1000I0；
Wherein, P0For the noise power of test point, PsFor the signal power of test point after unlatching numerical-control direct-current power source module；
IsFor the signal code of test point, I0For the interference electric current of test point, R0For the resistance value of test point sampling resistor.
Specifically, in step S4, the conduction resistance value calculation formula between the electrical equipment grounding downlead is as follows:
Wherein, R1、RrefFor standard divider resistance, and R1Much larger than Rref；UrefR when to measure conduction resistance valuerefBoth ends
Voltage value；UsR when to measure conduction resistance value1And RrefThe sum of the voltage value at both ends；Ur0To sample electricity when measurement conduction resistance value
Hinder R0The voltage value at both ends；RmFor the current-limiting resistance of numerical-control direct-current power source；RxFor the conducting resistance of pilot to be measured；Uin1For Ur0By
The voltage signal of processor is transferred to after amplification；Uin2For UrefThe voltage signal of processor is transferred to after amplification；K is difference
The amplification factor of amplifying circuit.
Compared with prior art, the utility model has the beneficial effects that (1) the utility model access working power it
Before, by the voltage signal of data acquisition circuit sampling resistor, interference electric current value is obtained after treatment, thus according to interference electricity
Flow valuve adjusts the output of working power, improves signal-to-noise ratio, eliminates influence of the interference electric current to test result, ensure that test number
According to accuracy；(2) the utility model can be determined according to accurately measurement data using the method for pincers meter method for measuring resistance value
Obstructed or conducting caused by poor contact or ground line internal fault can be effectively detected out in the conduction resistance value of test point
Bad phenomenon greatly improves the safety of power generation.
Detailed description of the invention
Fig. 1 is a kind of structural schematic block diagram of the smart grounding conduction detecting system of embodiment 1；
Fig. 2 is a kind of control flow block diagram of the smart grounding turn-on detecting method of embodiment 2；
Fig. 3 is split-core type meter method circuit measuring principle figure in embodiment 2；
Fig. 4 is a kind of simplified schematic diagram of smart grounding turn-on detecting method of embodiment 2.
Specific embodiment
Below in conjunction with the attached drawing in the utility model, the technical solution of the utility model is clearly and completely retouched
It states, it is clear that the described embodiments are only a part of the embodiments of the utility model, instead of all the embodiments.Based on this
Embodiment in utility model, those of ordinary skill in the art under the conditions of not making creative work it is obtained it is all its
Its embodiment, fall within the protection scope of the utility model.
Embodiment 1
As shown in Figure 1, present embodiments providing a kind of smart grounding conduction detecting system, including working power, data are adopted
Collector, differential amplifier circuit, A/D conversion circuit, processor and human-machine interface module；The output end and number of the working power
It is connected according to the input terminal of Acquisition Circuit, the output end of the data acquisition circuit and the input terminal of differential amplifier circuit connect, institute
The output end for stating differential amplifier circuit is connect with A/D conversion circuit input terminal, the output end of the differential amplifier circuit and processing
Device connection, the processor are also connect with human-machine interface module, working power respectively；The data acquisition circuit is arranged to be checked
It surveys between the down conductor of electrical equipment, for acquiring the voltage/current number of the connection resistance between equipment ground downlead
According to；The differential amplifier circuit is for amplifying the collected voltage/current signals of data acquisition circuit；The A/D turns
Circuit is changed for carrying out analog-to-digital conversion to amplified signal, and by the digital signal input processor after conversion；The processing
Device handles the signal received, obtain the resistance value between the down conductor of the electrical equipment, and will obtain
Resistance value shows tester by human-machine interface module.
The smart grounding conduction detecting system of the present embodiment chooses measurement point in conjunction with the actual conditions of tested earthing or grounding means,
Start detecting instrument after the completion of wiring, carrying out loop-around test come the connection for checking test clamp and electrical equipment grounding downlead is
It is no reliable, guarantee that test can be normally carried out；The present embodiment samples electricity before accessing working power, through data acquisition circuit
The voltage signal of resistance obtains interference electric current value after treatment, to adjust the output of working power according to interference electric current value, mentions
High signal-to-noise ratio, eliminates influence of the interference electric current to test result, ensure that the accuracy of test data.
Specifically, the data acquisition circuit includes low-frequency voltage measuring unit and low-frequency current measuring unit；It is described low
Frequency voltage/current measuring unit is used to measure the voltage/current data of resistance between the electrical equipment grounding downlead.
Specifically, the working power is numerical-control direct-current power source module, the output of the numerical-control direct-current power source module by
Device control is managed, the input of the numerical-control direct-current power source module is 220V alternating current.
Specifically, the human-machine interface module includes voice alerting unit, LCD display unit and communication output unit；Institute
LCD display unit is stated for showing the resistance value of tested pilot；The voice alerting unit is used to prompt the conductance of tested pilot
General character energy；Storage is numbered for test result to be transferred to database in the communication output unit.
Specifically, the processor uses STC12C5A60S2 series monolithic.
Specifically, the detection system further includes printer, when the detection system detects to obtain the electric conduction of test point
Resistance value, and after obtaining the current conduction of test point by processor analysis and distinguishing, result printing can be will test by printer
Out.
Embodiment 2
It is corresponding with the detection system of above-described embodiment, present embodiments provide a kind of smart grounding conduction detection side
Method, as shown in figure 3, method of the present embodiment using pincers meter method for measuring resistance value, is based on faraday electromagnetic induction principle, excitation pincers
Mouth is ac-excited to circuit progress, is detected by electric current jaw to loop current, to extract resistance information；U and I in figure
Respectively the voltage jaw input voltage of detection system and current clamp mouth inductive output electric current, RxFor measured resistance, R1、R2…Rn
For the resistance of other grounding points in the multiple grounding points of measurement equipment to be checked, usually there is Rx much larger than R1、R2…RnTotal electricity after parallel connection
Resistance, therefore the detection system is reduced to Fig. 4, wherein low-frequency voltage generator is equivalent to working power.
As shown in Fig. 2, the detection method of the present embodiment specifically includes the following steps:
S1, system initialization initialize the I/0 state of system, Memory Allocation space by processor；
S2 acquires the voltage signal at sampling resistor both ends between electrical equipment grounding downlead by data acquisition circuit,
Collected voltage signal input processor after the processing of differential amplifier circuit and A/D conversion circuit carries out data processing,
Obtain the interference electric current value between the electrical equipment grounding downlead；
S3 opens numerical-control direct-current power source module, the signal-to-noise ratio condition that should meet when according to the interference electric current value and detection
Carry out the output electric current of pre-adjustment numerical-control direct-current power source module；
S4 acquires sampling resistor both ends and electric conduction between electrical equipment grounding downlead by data acquisition circuit respectively
The voltage signal at both ends is hindered, and collected two voltage signals are passed through to the processing of differential amplifier circuit and A/D conversion circuit
Afterwards input processor carry out data processing, according to the program write in advance be calculated the electrical equipment grounding downlead it
Between conduction resistance value, be then shut off numerical-control direct-current power source module；
S5, processor differentiate the current conduction of test point according to the conduction resistance value, and it is single that processor controls LCD display
The conduction resistance value of test point is showed the electric current of tester, control voice alerting unit prompt tester's test point by member
Conduction, tester, which chooses whether test result being transferred to database, to be stored；Whether last reselection continues to test,
If do not continued, it is measured, shuts down.
Specifically, in step S1, system initialization specifically includes that single-chip microcontroller upper and lower reset, starting house dog journey automatically
Sequence, low-voltage detection circuit are resetted, the reset of LCD liquid crystal display screen and are configured to input/output port, at the beginning of system
The reasonability setting of beginningization is the essential condition that guarantee system operates normally.
Specifically, in step S2, the calculation formula of the interference electric current value are as follows: I0=U0/R0, wherein I0For interference electric current
Value, U0The voltage value at the sampling resistor both ends, R when to measure interference electric current value0For the resistance value of sampling resistor.
Specifically, in step S3, signal-to-noise ratio is not less than 60dB when the signal-to-noise ratio condition is test, according to the meter of signal-to-noise ratio
Formula is calculated to obtain:
It is finally calculated: Is≥1000I0；
Wherein, P0For the noise power of test point, PsFor the signal power of test point after unlatching numerical-control direct-current power source module；
IsFor the signal code of test point, I0For the interference electric current of test point, R0For the resistance value of test point sampling resistor；The processor
The output electric current of pre-adjustment numerical-control direct-current power source module is to export gear by switching the electric current of the numerical-control direct-current power source module
Come what is realized.
Specifically, in step S4, the conduction resistance value calculation formula between the electrical equipment grounding downlead is as follows:
Wherein, R1、RrefFor standard divider resistance, and R1Much larger than Rref；UrefR when to measure conduction resistance valuerefBoth ends
Voltage value；UsR when to measure conduction resistance value1And RrefThe sum of the voltage value at both ends；Ur0To sample electricity when measurement conduction resistance value
Hinder R0The voltage value at both ends；RmFor the current-limiting resistance of numerical-control direct-current power source；RxFor the conducting resistance of pilot to be measured；Uin1For Ur0By
The voltage signal of processor is transferred to after amplification；Uin2For UrefThe voltage signal of processor is transferred to after amplification；K is difference
The amplification factor of amplifying circuit.
Specifically, in step S5, the discrimination standard of the current conduction can be according to " DL/T475-2006 earthing or grounding means is special
Property parameter measurement directive/guide ": conduction resistance value is in 50m Ω hereinafter, earth conductor and ground lead are in good operating status；It leads
Energization resistance value illustrates that situation is fine within the scope of 50m Ω -200m Ω, its variation need to be paid close attention in later routine test,
The ground lead of important electrical need to the processing of inspection at the appropriate time；Conduction resistance value illustrates shape within the scope of 200m Ω -1 Ω
Condition is bad, need to ground lead to important electrical inspection is handled as early as possible, other equipment inspection at the appropriate time processing；Conducting
Resistance value illustrates that earth conductor and ground lead go wrong in 1 Ω or more, it is possible to which there is a situation where corrosion fractures, influence
The safe operation of earthing or grounding means needs the processing of inspection in time；Earth-continuity performance judgment criterion is as shown in table 1 below:
1 earth-continuity performance of table judges table
| Conduction resistance value R (m Ω) | 0-50 | 50≤R<200 | 200≤R<1000 | ≥1000 |
| Conduction property situation | Well | Still | It is bad | It is abnormal |
While there has been shown and described that the embodiments of the present invention, for the ordinary skill in the art,
It is understood that these embodiments can be carried out with a variety of variations in the case where not departing from the principles of the present invention and spirit, repaired
Change, replacement and variant, the scope of the utility model is defined by the appended claims and the equivalents thereof.
Claims (6)
1. a kind of smart grounding conduction detecting system, which is characterized in that including working power, data acquisition circuit, differential amplification
Circuit, A/D conversion circuit, processor and human-machine interface module；The output end of the working power and data acquisition circuit it is defeated
Enter end connection, the output end of the data acquisition circuit and the input terminal of differential amplifier circuit connect, the differential amplifier circuit
Output end connect with A/D conversion circuit input terminal, the output end of the differential amplifier circuit is connect with processor, the processing
Device is also connect with human-machine interface module, working power respectively；Connecing for electrical equipment to be detected is arranged in the data acquisition circuit
Between ground downlead, for acquiring the voltage/current data of the connection resistance between equipment ground downlead；The differential amplification
Circuit is for amplifying the collected voltage/current signals of data acquisition circuit；The A/D conversion circuit is used for amplification
Signal afterwards carries out analog-to-digital conversion；The processor is for handling the signal after analog-to-digital conversion, the human-machine interface mouth mold
Block is used to show testing result to tester.
2. a kind of smart grounding conduction detecting system according to claim 1, which is characterized in that the data acquisition circuit
Including low-frequency voltage measuring unit and low-frequency current measuring unit；Low-frequency voltage/the current measuring unit is described for measuring
The voltage/current data of resistance between electrical equipment grounding downlead.
3. a kind of smart grounding conduction detecting system according to claim 1, which is characterized in that the working power is number
DC power supplier is controlled, the output of the numerical-control direct-current power source module is controlled by processor.
4. a kind of smart grounding conduction detecting system according to claim 3, which is characterized in that the numerical-control direct-current power source
The input of module is 220V alternating current, is exported as direct current.
5. a kind of smart grounding conduction detecting system according to claim 1, which is characterized in that the human-machine interface module
Including voice alerting unit, LCD display unit and communication output unit；The LCD display unit is for showing tested pilot
Resistance value；What the voice alerting unit was used to prompt tested pilot conducts performance；The communication output unit will be for that will survey
Test result is transferred to database and is stored.
6. a kind of smart grounding conduction detecting system according to claim 1, which is characterized in that the processor includes
STC12C5A60S2 type single-chip microcontroller.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821953466.3U CN209446699U (en) | 2018-11-26 | 2018-11-26 | A kind of smart grounding conduction detecting system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821953466.3U CN209446699U (en) | 2018-11-26 | 2018-11-26 | A kind of smart grounding conduction detecting system |
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| CN209446699U true CN209446699U (en) | 2019-09-27 |
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2018
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