Invention content
The present invention provides a kind of capacitance type potential transformer test devices, overcome the deficiency of the above-mentioned prior art,
It can effectively solve that test process existing for existing detection device for voltage mutual inductor is cumbersome, and the testing time is long, test voltage grade is low
The problem of.
The technical scheme is that realized by following measures:A kind of capacitance type potential transformer test device,
Including high-voltage relay group, voltage transformer load blocks, booster, inductive voltage divider, power amplifier, analogue measurement electricity
Road, public machine and communication module, it is high that the high-voltage relay group includes the first high-voltage relay, the second high-voltage relay and third
Potential relay, the first high-voltage relay normally opened contact are electrically connected with the second high-voltage relay normally opened contact, the second high-voltage relay
Normally opened contact is electrically connected with third high-voltage relay normally opened contact, the second end ground connection of third high-voltage relay normally opened contact;Institute
It states analog measuring circuit and includes difference voltage measuring circuit, normal voltage measuring circuit and A/D modular converters, normal voltage measures
Circuit includes phase-locked loop circuit, voltage transformer, the first precision resistance division module, normal voltage amplification module, the first filtering
Circuit, difference voltage measuring circuit include the second precision resistance division module, difference voltage amplification module and the second filter circuit;
Public machine include processing module and D/A modular converters, processing module respectively with the first high-voltage relay coil, the second high-voltage relay
Device coil, third high-voltage relay coil, voltage transformer load blocks and D/A modular converters electrical connection, D/A modular converters with
Power amplifier is electrically connected, and power amplifier is electrically connected with the input terminal of booster, the first output wiring terminal of booster difference
With the input of the second end and inductive voltage divider of the second high-voltage relay normally opened contact is high-end is electrically connected, the output ground connection of booster first
Terminal is grounded with inductive voltage divider input low side, and booster second output terminal is electrically connected with voltage transformer, mutual induction of voltage
Device, the first precision resistance division module, normal voltage amplification module and the first filter circuit are sequentially connected, the first filter circuit
Output terminal is electrically connected respectively with phase-locked loop circuit and A/D modular converters, and phase-locked loop circuit is electrically connected with A/D modular converters, sensing
Divider output is high-end to be electrically connected with the second precision resistance division module, the second precision resistance division module, difference voltage amplification
Module and the second filter circuit are sequentially connected, and the second filter circuit is electrically connected with A/D modular converters, A/D modular converters and processing
Module is electrically connected, and processing module is electrically connected with communication module.
Here is the further optimization and/or improvements to foregoing invention technical solution:
Above-mentioned standard voltage amplification module may include the first normal voltage amplifying circuit and the second standard electric sequentially connected
Amplifying circuit is pressed, the first precision resistance division module is electrically connected with the first normal voltage amplifying circuit, the amplification of the second normal voltage
Circuit is electrically connected with the first filter circuit.
Above-mentioned difference voltage amplification module may include the first difference voltage amplifying circuit sequentially connected, third filtered electrical
Road, the second difference voltage amplifying circuit and third difference voltage amplifying circuit, the second precision resistance division module and the first difference
Voltage amplifier circuit is electrically connected, and third difference voltage amplifying circuit is electrically connected with the second filter circuit.
Above-mentioned second precision resistance division module may include the accurate electricity of the first precision resistance, the second precision resistance and third
Resistance, the first precision resistance are electrically connected with the second precision resistance, and the second precision resistance is electrically connected with third precision resistance, in the second essence
The both ends of cipher telegram resistance are parallel with handover module, and inductive voltage divider exports the high-end second end with third precision resistance and is electrically connected, the
The second end of three precision resistances and the output terminal of handover module are electrically connected with the first difference voltage amplifying circuit.
Above-mentioned voltage transformer load blocks may include the first relay, the second relay and third relay, first after
Electric apparatus coil, the second relay coil and third relay coil are electrically connected with processing module, the first relay normally open contact,
The second end of second relay normally open contact and third relay normally open contact is electrically connected there are one load resistance.
Above-mentioned voltage transformer can be accurate voltage mutual inductor, and communication module can be RS232 modules.
It is above-mentioned to may also include insulation shell, display module, communication interface, three high-voltage relays are installed on insulation shell
Device group binding post, two measure binding posts and six load wiring columns, display module and be electrically connected with processing module, communication interface and
Communication module is electrically connected, three high-voltage relay group binding posts respectively with the first end of the first high-voltage relay normally opened contact, the
The second end of two high-voltage relay normally opened contacts and the second end electrical connection of third high-voltage relay normally opened contact, two measurements connect
The first end that terminal exports low side and the first precision resistance with inductive voltage divider respectively is electrically connected, six load wiring columns respectively with
First relay normally open contact, the first end of the second relay normally open contact and third relay normally open contact and three load electricity
The second end electrical connection of resistance.
Beneficial effects of the present invention:
1st, the open and-shut mode of high-voltage relay normally opened contacts all in high-voltage relay group is carried out various combination by the present invention,
Switching measured capacitance formula voltage transformer primary side wire connection terminal is made to access booster and inductive voltage divider with different states, by
This then need not artificially participate in disconnecting for measured capacitance formula voltage transformer primary side wire connection terminal, avoid manual operation mistake,
And high-voltage relay group only needs the time of about 100mS that switching action can be completed, and reduces the testing time, improves work effect
Rate;
2nd, the class of accuracy of the inductive voltage divider in the present invention can reach 0.02 grade, and the measurement made using electronic component
Circuit is extremely difficult to 0.05 grade, and temperature characterisitic is not so good as using inductive voltage divider, therefore the present invention improves measurement accuracy, simultaneously
The no-load voltage ratio of the capacitance type potential transformer of 35kV to 765kV can be covered using inductive voltage divider, expands the measurement of the present invention
Range.
3rd, present invention employs power amplifiers, improve the stability of device boosting, reduce failure rate.
4th, this invention simplifies the wiring of tester work, and farthest avoiding artificially leads to asking for wiring error
Topic, reduces the dependence to tester's experience and ability, improves safety.
5th, test voltage of the present invention is no more than 10000V, and capacity is no more than 500VA, and it is public that tester host weight is no more than 35
Jin;The time for testing a capacitance type potential transformer is less than 3.5 minutes.It solves and verifies condenser type using traditional calibration equipment
The problem of equipment volume weight is big caused by voltage transformer, and test voltage is not high, and capacity is little.
Specific embodiment
The present invention is not limited by following embodiments, can be determined according to the technique and scheme of the present invention with actual conditions specific
Embodiment.
With reference to embodiment and attached drawing, the invention will be further described:
As shown in attached drawing 1,2,3,4,5,6,7,8, the capacitance type potential transformer test device, including high-voltage relay
Group, voltage transformer load blocks, booster, inductive voltage divider, power amplifier, analog measuring circuit, public machine and communication
Module, the high-voltage relay group include the first high-voltage relay, the second high-voltage relay and third high-voltage relay, and first is high
Potential relay normally opened contact S1-1 is electrically connected with the second high-voltage relay normally opened contact S2-1, the second high-voltage relay normally opened contact
S2-1 is electrically connected with third high-voltage relay normally opened contact S3-1, the second termination of third high-voltage relay normally opened contact S3-1
Ground;The analog measuring circuit includes difference voltage measuring circuit, normal voltage measuring circuit and A/D modular converters, standard electric
Measuring circuit is pressed to include phase-locked loop circuit, voltage transformer, the first precision resistance division module, normal voltage amplification module, the
One filter circuit, difference voltage measuring circuit include the second precision resistance division module, difference voltage amplification module and the second filter
Wave circuit;Public machine includes processing module and D/A modular converters, processing module respectively with the first high-voltage relay coil S1, the
Two high-voltage relay coil S2, third high-voltage relay coil S3, voltage transformer load blocks and D/A modular converters are electrically connected
It connects, D/A modular converters are electrically connected with power amplifier, and power amplifier is electrically connected with the input terminal of booster, booster first
Output wiring terminal 1a ' inputs high-end A with the second end of the second high-voltage relay normally opened contact S2-1 and inductive voltage divider respectively
Electrical connection, booster first export ground terminal 1n ' and inductive voltage divider input low side X and are grounded, booster second output terminal
Son is electrically connected with voltage transformer, voltage transformer, the first precision resistance division module, normal voltage amplification module and the first filter
Wave circuit is sequentially connected, and the output terminal of the first filter circuit is electrically connected respectively with phase-locked loop circuit and A/D modular converters, phaselocked loop
Circuit is electrically connected with A/D modular converters, and inductive voltage divider exports high-end a and is electrically connected with the second precision resistance division module, and second
Precision resistance division module, difference voltage amplification module and the second filter circuit are sequentially connected, and the second filter circuit is converted with A/D
Module is electrically connected, and A/D modular converters are electrically connected with processing module, and processing module is electrically connected with communication module.
Here phase-locked loop circuit, voltage transformer, the first precision resistance division module, first in normal voltage measuring circuit
Filter circuit is existing known technology, and normal voltage measuring circuit is mainly used for measuring the standard electric of voltage transformer output
Pressure, wherein voltage transformer are used for the sampling of standard voltage signal, and leading indicator is voltage than 2000V/20V, class of accuracy
0.02 grade, secondary load 0VA;Phase-locked loop circuit to tested AC signal as shown in figure 5, for carrying out complete cycle wave sampling, master
Wanting principle is:By gain it is that generate a duty ratio be 50% just to infinitely great amplifying circuit first by tested AC signal
Losing side wave is being converted into half-wave by LM311 comparators, and half-wave enters the input pin of phase-locked loop chip, phase-locked loop chip general side
Wave signal is subject to frequency multiplication, and frequency-doubled signal feeds back to the feedback pin of phaselocked loop by accumulator so that feedback signal is believed with input
Number consistent, the correspondence pin of accumulator is had with square-wave signal into 2 at this timenThe square-wave signal of multiple, pin output signal frequency
As shown in table 1, if the Pulse Width Control A/D modular converters that multiple selector 74LS151 selection phaselocked loops Q8 is generated, a 50Hz
256 points of sinusoidal wave measurement, since normal voltage and normal voltage are same sine wave, processing module is thought standard
Voltage and difference voltage are by there is 256 measurement data, so as to obtain normal voltage, difference voltage by fft algorithm
Amplitude size and phase;The characteristics of first precision resistance division module has resistance error size, and precision is high, so as to reduce
Normal voltage measurement error;First filter circuit can be voltage-controlled second-order low-pass filter as shown in Figure 7, can be to fundamental wave other than
Higher hamonic wave effectively inhibit, so as to accurately measuring fundamental signal in having test signal existing for harmonic wave.
Here the second precision resistance division module and the second filter circuit are existing known in difference voltage measuring circuit
Technology, difference voltage measuring circuit are mainly used for measuring the difference voltage of inductive voltage divider and measured capacitance formula voltage transformer;
Second precision resistance division module can be a precision resistance;Second filter circuit can be voltage-controlled second-order low-pass filter, can
Higher hamonic wave other than fundamental wave is effectively inhibited, so as to accurately measure fundamental signal in having test signal existing for harmonic wave.
Here processing module is existing known technology, and the digital signal processor of 32 can be used, and is mainly used for control electricity
Mutual inductor load blocks are pressed, control booster boosting receives the measurement of normal voltage measuring circuit and difference voltage measuring circuit
Value, calculate the error of measured capacitance formula voltage transformer according to the measured value that receives, i.e. measured capacitance formula voltage transformer
Low pressure zero load ratio error and angular error, and pass through digital interface i.e. I/O mouthfuls of the first high-voltage relay of output voltage control,
The coil of second high-voltage relay and third high-voltage relay;D/A modular converters are existing known technology, can generate 50HZ just
String wave, processing module control the size of its amplitude;Power amplifier is existing known technology, for defeated according to D/A modular converters
The amplitude gone out carries out power amplification, while power amplifier can be powered by 200V DC power supplies;Booster is existing known technology,
For boosting according to the power that power amplifier exports, 10000V can be risen to;Inductive voltage divider can be used adjustable no-load voltage ratio,
Standard electrician's formula inductive voltage divider of 0.02 grade of class of accuracy, standard electrician's formula inductive voltage divider are adjusted using 6 disks, have no-load voltage ratio
100 to 100000000 range capabilities are covered, no-load voltage ratio is adjusted according to measured capacitance formula voltage transformer famous brand information;Mutual induction of voltage
Device load blocks can be voltage transformer load box, be mainly used for measured capacitance formula voltage transformer input load;Communicate mould
Block is existing known technology, for the communication between processing module and computer.
Testing procedure is as follows:
1st, it is as shown in figure 8, the primary side wire connection terminal of measured capacitance formula voltage transformer and the first high-voltage relay is normal
The first end connection of contact S1-1 is opened, is electrically connected booster and the primary side wire connection terminal of measured capacitance formula voltage transformer,
Primary side ground terminal with the second end of the second high-voltage relay normally opened contact S2-1 is connect, makes measured capacitance formula mutual induction of voltage
The primary side ground terminal ground of device, the ground terminal of compensation reactor and the second segment of third high-voltage relay normally opened contact S3-1
Electrical connection, secondary No.1 winding wire connection terminal, secondary No.1 winding ground terminal, secondary No. two windings wire connection terminal, secondary two
Number winding ground terminal, residual voltage wire connection terminal and residual voltage ground terminal are connect with voltage transformer load blocks,
Secondary No.1 winding ground terminal is connect with inductive voltage divider output low side n, secondary No.1 winding wire connection terminal and the second precision
Electric resistance partial pressure module connects;
2nd, staff is according to the name plate information of measured capacitance formula voltage transformer, by the nominal load and lower limit in nameplate
Load parameter is entered by computer and communication module in processing module, and wherein the power factor of typing is 0.8;
3rd, processing module is by controlling the output work of the big minor adjustment power amplifier of amplitude of D/A modular converter output waveforms
Rate, booster boost according to the output power of power amplifier, and normal voltage measuring circuit measures the output electricity of booster
Pressure, and processing module is sent to, if the output voltage of booster does not reach processing module and requires raised voltage, continue to change
Become the amplitude size of D/A modular converter output waveforms, boost, until voltage rises to required high pressure, make inductive voltage divider
Error of measurement circuit is formed with measured capacitance formula voltage transformer;
4th, processing module gives the first high-voltage relay coil S1 and third high-voltage relay coil S3 power transmissions, makes the first high pressure
Relay normally open contact S1-1 and third high-voltage relay normally opened contact S3-1 is closed;
5th, processing module controls the voltage transformer load blocks not input load into measured capacitance formula voltage transformer, makes
In the case that measured capacitance formula voltage transformer is in not bringing onto load, the voltage of booster second output terminal output is through overvoltage
To be surveyed after mutual inductor, the first precision resistance division module, normal voltage amplification module, the first filter circuit, phase-locked loop circuit
The normal voltage obtained, the normal voltage are sent into processing module by A/D modular converters, and inductive voltage divider exports high-end a outputs
Voltage and the voltage of measured capacitance formula voltage transformer secondary No.1 winding wire connection terminal output are divided into the second precision resistance
Module forms difference voltage, and the difference voltage is through the second precision resistance division module, difference voltage amplification module and the second filter
It is measured difference voltage after wave circuit, then the difference voltage is sent into processing module, processing module by A/D modular converters
The low pressure zero load ratio error of measured capacitance formula voltage transformer at this time is calculated according to normal voltage and difference voltage and angle is missed
Difference is denoted as no-load error;
6th, processing module controls voltage transformer load blocks mutual to measured capacitance formula voltage according to the name plate information of input
It loads, makes in the case of measured capacitance formula voltage transformer is in load-carrying, repeatedly the 4th step, is surveyed later needed for being inputted in sensor
Normal voltage and difference voltage are measured, processing module is finally made to calculate measured capacitance formula electricity at this time according to normal voltage and difference voltage
The low pressure zero load ratio error and angular error of mutual inductor are pressed, is denoted as resistive load error;
7th, processing module is by no-load error (f0、δ0), resistive load S1Error (f1、δ1) (resistive load power factor φ1=
1.0), rated load S2, power factor φ2=0.8 brings formula into, obtains rated load S2, power factor φ2Being somebody's turn to do under=0.8
The error of measured capacitance formula voltage transformer, formula are as follows:
Here in the 4th step processing module can according to the difference of test method, to different high-voltage relay coil power transmissions,
It is allowed to corresponding high-voltage relay normally opened contact to be closed, so as to make subject capacitance type potential transformer primary side wire connection terminal with not
Same state access booster and inductive voltage divider, such as equivalent circuit test method, excitation characteristic test method.
Beneficial effects of the present invention:
1st, the open and-shut mode of high-voltage relay normally opened contacts all in high-voltage relay group is carried out various combination by the present invention,
Switching measured capacitance formula voltage transformer primary side wire connection terminal is made to access booster and inductive voltage divider with different states, by
This then need not artificially participate in disconnecting for measured capacitance formula voltage transformer primary side wire connection terminal, avoid manual operation mistake,
And high-voltage relay group only needs the time of about 100mS that switching action can be completed, and reduces the testing time, improves work effect
Rate;
2nd, the class of accuracy of the inductive voltage divider in the present invention can reach 0.02 grade, and the measurement made using electronic component
Circuit is extremely difficult to 0.05 grade, and temperature characterisitic is not so good as using inductive voltage divider, therefore the present invention improves measurement accuracy, simultaneously
The no-load voltage ratio of the capacitance type potential transformer of 35kV to 765kV can be covered using inductive voltage divider, expands the measurement of the present invention
Range.
3rd, present invention employs power amplifiers, improve the stability of device boosting, reduce failure rate.
4th, this invention simplifies the wiring of tester work, and farthest avoiding artificially leads to asking for wiring error
Topic, reduces the dependence to tester's experience and ability, improves safety.
5th, test voltage of the present invention is no more than 10000V, and capacity is no more than 500VA, and it is public that tester host weight is no more than 35
Jin;The time for testing a capacitance type potential transformer is less than 3.5 minutes.It solves and verifies condenser type using traditional calibration equipment
The problem of equipment volume weight is big caused by voltage transformer, and test voltage is not high, and capacity is little.
Above-mentioned capacitance type potential transformer test device can be made further optimization and/or improvements according to actual needs:
As shown in attached drawing 1,6,7, the normal voltage amplification module includes the first normal voltage sequentially connected amplification electricity
Road and the second normal voltage amplifying circuit, the first precision resistance division module are electrically connected with the first normal voltage amplifying circuit, the
Two normal voltage amplifying circuits are electrically connected with the first filter circuit.
Here the first normal voltage amplifying circuit and the second normal voltage amplifying circuit are existing known technology, can be journey
Signal amplification circuit is controlled, program control signal amplifying circuit is controlled as shown in fig. 6, using operational amplifier TLE2022 using ADG409
The ratio of feedback signal, so as to control gain, the range of its programmable amplifying circuit as shown in table 2 is 1 times to 64 times.
As shown in attached drawing 1,4,6,7, the difference voltage amplification module includes the first difference voltage sequentially connected amplification
Circuit, third filter circuit, the second difference voltage amplifying circuit and third difference voltage amplifying circuit, the second precision resistance partial pressure
Module is electrically connected with the first difference voltage amplifying circuit, and third difference voltage amplifying circuit is electrically connected with the second filter circuit.
Here the first difference voltage amplifying circuit, the second difference voltage amplifying circuit and third difference voltage amplifying circuit are equal
For program control signal amplifying circuit, 3 programmable amplifying circuits, highest can amplify 260,000 times here, can be by 3uV voltage 1V voltages
Left and right, fully meets the measuring and amplifying needs of small-signal, accuracy of measurement is allow to reach 1 grade.Third filter circuit is existing
There is known technology, can be voltage-controlled second-order low-pass filter.
As shown in attached drawing 1,4, the second precision resistance division module includes the first precision resistance R1, the second precision resistance
R2 and third precision resistance R3, the first precision resistance R1 are electrically connected with the second precision resistance R2, the second precision resistance R2 and third
Precision resistance R3 is electrically connected, and is parallel with handover module at the both ends of the second precision resistance R2, and inductive voltage divider exports high-end a and the
The second end electrical connection of three precision resistance R3, the second end of third precision resistance R3 and the output terminal of handover module are poor with first
Threshold voltage amplifying circuit is electrically connected.
Here the first precision resistance R1, the second precision resistance R2 and third precision resistance R3 composition resistor voltage divider network and
Using accurate type wire wound resistor, resistance value is respectively 20k Ω, 10k Ω and 100 Ω;Handover module can be relay handover module;
When difference voltage is less than 2V, upper arm resistance is 20k Ω, and underarm resistance is 10.1k Ω, and partial pressure coefficient is
0.33555;When test signal is more than or equal to 2V, upper arm resistance is 30k Ω, and underarm resistance is 100 Ω, divides coefficient
It is 0.003322.During test, the first end of the first precision resistance R1 is wound with the secondary No.1 of measured capacitance formula voltage transformer
Wire connection terminal connects.
As shown in attached drawing 1,3,8, the voltage transformer load blocks include the first relay, the second relay and third
Relay, the first relay coil K1, the second relay coil K2 and third relay coil K3 are electrically connected with processing module,
The second end of first relay normally open contact K1-1, the second relay normally open contact S2-1 and third relay normally open contact K3-1
There are one load resistances for electrical connection.
Here the first relay coil K1 of processing module control, the second relay coil K2 and third relay coil K3 are
It is electricly no, if coil obtains electric, normally opened contact closure corresponding with the coil, so as to make load resistance access measured capacitance formula electricity
It presses in mutual inductor, load resistance is purely resistive here, can be 33.33 ohm.The present invention simplifies device by resistive load, subtracts
Small installation weight, without additionally increasing voltage transformer load box.
As needed, the voltage transformer is accurate voltage mutual inductor, and communication module is RS232 modules.
As shown in attached drawing 1,8, further include insulation shell, be equipped on insulation shell display module, communication interface, three
High-voltage relay group binding post, two measurement binding posts and six load wiring columns, display module are electrically connected with processing module, are led to
Letter interface be electrically connected with communication module, three high-voltage relay group binding posts respectively with the first high-voltage relay normally opened contact S1-1
First end, the second end of the second high-voltage relay normally opened contact S2-1 and third high-voltage relay normally opened contact S3-1 second
End electrical connection, two measure first end of the binding post respectively with inductive voltage divider output low side n and the first precision resistance R1 and are electrically connected
Connect, six load wiring columns respectively with the first relay normally open contact K1-1, the second relay normally open contact S2-1 and third after
The second end electrical connection of the first end of electric appliance normally opened contact K3-1 and three load resistances.
Here insulation shell can be macromolecule polymeric material shell.Electrical equipment is sealed in housing using insulation crust
Portion makes staff touch less than high pressure, securely and reliably.
More than technical characteristic constitutes highly preferred embodiment of the present invention, is imitated with stronger adaptability and best implementation
Fruit can increase and decrease non-essential technical characteristic, to meet the needs of different situations according to actual needs.
1 pin output signal frequency of table
The range of 2 programmable amplifying circuit of table
Control signal a0 |
Control signal a1 |
Upper arm resistance (k Ω) |
Underarm resistance (k Ω) |
Amplification factor AV |
0 |
0 |
0 |
R2+R3+R4+R5=64 |
1 |
1 |
0 |
R2=48 |
R3+R4+R5=16 |
4 |
0 |
1 |
R2+R3=60 |
R4+R5=4 |
16 |
1 |
1 |
R2+R3+R4=63 |
R5=1 |
64 |