CN209746065U - Automatic detector for protecting secondary circuit wiring - Google Patents
Automatic detector for protecting secondary circuit wiring Download PDFInfo
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- CN209746065U CN209746065U CN201920414925.9U CN201920414925U CN209746065U CN 209746065 U CN209746065 U CN 209746065U CN 201920414925 U CN201920414925 U CN 201920414925U CN 209746065 U CN209746065 U CN 209746065U
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- 238000006243 chemical reaction Methods 0.000 claims abstract description 11
- 238000002847 impedance measurement Methods 0.000 claims abstract description 10
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Abstract
the utility model discloses a protection secondary circuit wiring automatic detector, which comprises a housin, be provided with binding post, display, micro printer and operation button on the casing, be provided with input terminal, input switching circuit, sinusoidal inverter circuit, impedance measurement sampling circuit, direct current high voltage generating circuit, insulation resistance measurement sampling circuit, analog-to-digital conversion circuit and controller in the casing. The utility model provides a technical scheme, can realize the switching of insulation resistance test function between secondary circuit impedance test function and the sinle silk, the inefficiency that exists when having not only solved among the prior art and adopting the universal meter voltage method to measure, measure inconvenient and because contact failure produces the problem of error, when the return circuit is more still solved simultaneously, measure the huge and very easily wrong problem of leaking of insulation resistance change wiring work load between the different return circuits, and automatic output testing result when measuring at every turn, can preserve and print the generation report, measured data's the fake has effectively been stopped.
Description
Technical Field
The embodiment of the utility model provides a relate to power plant, transformer substation technical field, especially relate to a protection secondary circuit wiring automatic detector.
Background
The secondary circuit of the transformer substation voltage transformer cannot be short-circuited, the secondary circuit of the current transformer cannot be open-circuited, wiring must follow the rule, and otherwise the transformer cannot safely and reliably run. The situation of poor contact caused by the fact that the wiring terminal is loosened difficultly to be perceived is inevitable on site, and the safe operation of the mutual inductor is seriously threatened; therefore, a device is needed to measure the secondary loop impedance of the voltage/current transformer to determine whether the connection is reliable, the secondary loop impedance of the voltage transformer cannot be smaller than a certain value (regarded as short circuit) and the secondary loop impedance of the current transformer cannot be larger than a certain value (regarded as open circuit). The risk points that the secondary loop wire is poor in contact, aged and the like to influence the reliable operation of the protection device are found before the protection device is put into operation, and therefore the safety accidents are greatly reduced.
the insulation resistance between the circuits is measured for the construction acceptance and the regular inspection maintenance of the protection secondary circuit. If the cable core is not insulated, the current sampling accuracy is influenced, and the secondary circuit is burnt and even the protection device malfunctions due to heating in serious conditions, so that the protection malfunction is caused. According to the requirement of relay protection inspection regulations, a 1000V megohmmeter is used for measuring the insulation resistance between each loop (wire core) and the ground and between each loop (wire core) before the wiring of a newly-installed device screen cabinet, and the resistance values of the insulation resistance are all larger than 10M omega. In the field construction process and ordinary maintenance, circuit insulation aging caused by rough dragging in the cable laying process, falsification of insulation measurement data of constructors and long-term operation of a secondary circuit brings hidden dangers to safe operation of power transformation equipment, and in recent years, power safety accidents caused by the cable insulation problem occur.
SUMMERY OF THE UTILITY MODEL
The utility model provides a protection secondary circuit wiring automatic detector to solve the not enough of prior art.
In order to achieve the above object, the present invention provides the following technical solutions:
an automatic detector for protecting secondary circuit wiring has a secondary circuit impedance test function and an insulation resistance test function between wire cores, and comprises a shell, wherein a wiring terminal, a display, a micro printer and an operation key are arranged on the shell, and an input terminal, an input switching circuit, a sine inverter circuit, an impedance measurement sampling circuit, a direct-current high-voltage generating circuit, an insulation resistance measurement sampling circuit, an analog-to-digital conversion circuit and a controller are arranged in the shell; wherein,
The display, the micro printer and the operation keys are respectively connected with the controller;
The input end of the input terminal is connected with the wiring terminal, and the output end of the input terminal is connected with the input end of the input switching circuit;
The input end of the impedance measurement sampling circuit is respectively connected with the output end of the input switching circuit and the output end of the sine inverter circuit, and the output end of the impedance measurement sampling circuit is connected with the controller through the analog-to-digital conversion circuit;
the input end of the insulation resistance measuring and sampling circuit is respectively connected with the output end of the input switching circuit and the output end of the direct-current high-voltage generating circuit, and the output end of the insulation resistance measuring and sampling circuit is connected with the controller through the analog-to-digital conversion circuit.
Furthermore, the automatic protection secondary circuit wiring detector also comprises a function switch driven by an IO port of the controller;
The function switch is arranged on the shell and between the input terminal and the input switching circuit and used for realizing the switching of the secondary loop impedance test function and the insulation resistance test function between the wire cores.
Furthermore, in the automatic protection secondary circuit wiring detector, the number of the wiring terminals is 16, the 16 wiring terminals are divided into an upper row and a lower row which are the same in number, and the wiring terminals in each row are distributed at intervals.
Furthermore, in the automatic protection secondary circuit wiring detector, the number of the operation keys is 3, and the operation keys are respectively a test key, a print key and a setting key.
furthermore, in the automatic protective secondary circuit wiring detector, the casing comprises a front casing and a rear casing which are detachable, an assembly groove is formed in the inner side of the side wall of the rear casing, and an assembly bump matched with the assembly groove is formed in the outer side of the side wall of the front casing;
the wiring terminal, the display, the micro printer and the operation keys are arranged on the front shell.
Further, in the automatic protective secondary circuit wiring detector, the display is an LCD display or an LED display.
Further, in the automatic detector for protecting secondary circuit wiring, the controller is one of a central processing unit, a programmable logic controller, a single chip microcomputer or an embedded processor.
The embodiment of the utility model provides a pair of protection secondary circuit wiring automatic detector, can realize the switching of insulation resistance test function between secondary circuit impedance test function and the sinle silk, the inefficiency that exists when having not only solved among the prior art and adopting the universal meter voltage method to measure, measure inconvenient and because contact failure produces the problem of error, the while has still solved the return circuit when more, measure the huge and very easily the problem of mistake hourglass of insulation resistance change wiring work load between the different return circuits, and automatic output testing result when measuring at every turn, can preserve and print the generation report, effectively stopped measuring data's fake, small has in addition, light in weight, safe and reliable's advantage.
drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without inventive exercise.
Fig. 1 is a schematic structural diagram of an automatic detector for protecting secondary circuit wiring according to an embodiment of the present invention;
Fig. 2 is a schematic structural diagram of an automatic detector for protecting secondary circuit wiring according to an embodiment of the present invention;
fig. 3 is a schematic circuit diagram of an input switching circuit according to an embodiment of the present invention;
Fig. 4 is a schematic circuit diagram of a switching circuit of a function switch according to an embodiment of the present invention;
fig. 5 is a schematic circuit structure diagram of an insulation resistance measurement sampling circuit according to an embodiment of the present invention.
reference numerals:
The device comprises a shell 10, a wiring terminal 20, a display 30, a micro printer 40, an operation key 50, a function switch 60, an input terminal 70, an input switching circuit 80, a sine inverter circuit 90, an impedance measurement sampling circuit 100, a direct-current high-voltage generating circuit 110, an insulation resistance measurement sampling circuit 120, an analog-to-digital conversion circuit 130 and a controller 140.
Detailed Description
in order to make the objects, features and advantages of the present invention more obvious and understandable, the embodiments of the present invention are clearly and completely described with reference to the drawings in the embodiments of the present invention, and obviously, the embodiments described below are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
In the description of the present invention, it is to be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present.
Furthermore, the terms "long", "short", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are only for convenience of describing the present invention, but do not indicate or imply that the device or element referred to must have the specific orientation, operate in the specific orientation configuration, and thus, should not be construed as limiting the present invention.
The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings.
Example one
Referring to fig. 1-2, an embodiment of the present invention provides an automatic detector for protecting secondary circuit wiring, which has a secondary circuit impedance test function and a core insulation resistance test function, and includes a housing 10, wherein the housing 10 is provided with a connection terminal 20, a display 30, a micro printer 40 and an operation key 50, and the housing 10 is provided with an input terminal 70, an input switching circuit 80, a sine inverter circuit 90, an impedance measurement sampling circuit 100, a dc high voltage generation circuit 110, an insulation resistance measurement sampling circuit 120, an analog-to-digital conversion circuit 130 and a controller 140; wherein,
The display 30, the micro printer 40 and the operation keys 50 are respectively connected with the controller 140;
An input end of the input terminal 70 is connected to the connection terminal 20, and an output end of the input terminal 70 is connected to an input end of the input switching circuit 80;
The input end of the impedance measurement sampling circuit 100 is connected to the output end of the input switching circuit 80 and the output end of the sine inverter circuit 90, respectively, and the output end of the impedance measurement sampling circuit 100 is connected to the controller 140 through the analog-to-digital conversion circuit 130;
The input end of the insulation resistance measuring and sampling circuit 120 is connected to the output end of the input switching circuit 80 and the output end of the dc high voltage generating circuit 110, and the output end of the insulation resistance measuring and sampling circuit 120 is connected to the controller 140 through the analog-to-digital conversion circuit 130.
preferably, the detector further includes a function switch 60 driven by an IO port of the controller 140;
the function switch 60 is disposed on the housing 10 and between the input terminal 70 and the input switching circuit 80, and is used for switching between a secondary loop impedance test function and a core insulation resistance test function.
In this embodiment, the number of the connection terminals 20 is 16, 16 connection terminals 20 are divided into two upper and lower rows with the same number, the connection terminals 20 in each row are distributed at intervals and directly connected to the input terminal 70 of the secondary circuit, and the impedance test of the secondary circuit of the 8-circuit current/voltage transformer can be completed by one-time connection after the test is started.
insulation resistance measurement under different voltage levels of 500V, 1000V and 1500V can be set. And the automatic detection of the multi-loop insulation resistance is supported. And automatically switching to measure the insulation between the secondary loops or the insulation of the secondary loops to the ground. The IO port of the controller 140 drives the control function switch 60 to be turned on, so that the measurement function of the input terminal 70 is controlled to be switched, and the insulation resistance measurement between any two of the multiple input ends of the secondary circuit is realized.
The number of the operation keys 50 is 3, and the operation keys are respectively a test key, a print key and a setting key.
Preferably, the housing 10 includes a front housing and a rear housing which are detachable, an assembly groove is formed on the inner side of the side wall of the rear housing, and an assembly bump matched with the assembly groove is formed on the outer side of the side wall of the front housing;
The connection terminal 20, the display 30, the micro printer 40, and the operation keys 50 are provided on the front case.
in the present embodiment, the display 30 is an LCD display or an LED display.
the controller 140 is one of a central processing unit, a programmable logic controller, a single chip microcomputer, or an embedded processor.
As can be seen from fig. 1, the testing apparatus can perform the secondary circuit impedance test and the insulation resistance test between the cores through the function switch 60. When the function switch 60 is switched to the impedance test, a1 and a2 are in one group, B1 and B2 are in one group, C1 and C2 are in one group, D1 and D2 are in one group, E1 and E2 are in one group, F1 and F2 are in one group, G1 and G2 are in one group, and H1 and H2 are in one group, and eight groups of secondary circuits can be tested at the same time. The setting key can select a voltage transformer or a current transformer. After the test key is pressed, the test is started, and after the test is finished, the print key is pressed to print and output.
when the function selector switch 60 is toggled to the insulation resistance test, the insulation resistance test can be performed on all combinations of any two of 16 inputs, i.e., a1, a2, B1, B2, C1, C2, D1, D2, E1, E2, F1, F2, G1, G2, H1, and H2. Different test voltages can be selected by the setting key, the test is started after the test key is pressed, and the printing key is pressed after the test is finished to print and output.
As shown in fig. 3, the function switch 60K is a single-pole double-throw relay, and the output of the IO port of the controller 140 is amplified by a transistor and drives the relay to control the on-state of the relay, and the control input 1 is connected to the output 2 or the output 3.
in the present embodiment, as shown in fig. 4, the input switching circuit 80 has all the terminals 20 connected to the function control relays, i.e., a1 connected to 1 of AK1, a2 connected to 1 of AK2, B1 connected to 1 of BK1, B2 connected to 1 of BK2, C1 connected to 1 of CK1, C2 connected to 1 of CK2, and so on until H1 connected to 1 of HK1, and H2 connected to 1 of HK 2. When relays AK1, AK2, BK1, BK2, CK1, CK2 … HK1, HK2 select 2 outputs, the function is an insulation resistance function, and when 3 outputs are selected, the function is an impedance test function. When the impedance test is carried out, the impedance between the A1 loop and the A2 loop is firstly carried out, the microprocessing control outputs AK1 and AK2 as 3, and outputs BK1, BK2, CK1, CK2 … HK1 and HK2 are selected as 2, so that only A1 is directly connected to a sinusoidal inversion signal source output Z1, A2 is directly connected to a sinusoidal inversion signal source output Z2 for testing, and after the testing is finished, tests B1, B2, C1, C2 … H1 and H2 are sequentially switched.
When the insulation resistance test is carried out, the AK1, AK2, BK1, BK2, CK1, CK2 … HK1 and HK2 relays can be used for selectively outputting 2 to the cores to be tested, the next-level control relay is accessed, and insulation resistance test ends L and E are selectively accessed, so that each core can be accessed respectively, the L and the E can be accessed to different cores respectively, and the insulation resistance between the cores can be measured respectively through multiple combination.
in the embodiment, a sinusoidal inversion technology of driving an H bridge by an SPWM is adopted, sinusoidal voltage signals or current signals are output according to different secondary loops of the PTCT, and parameters such as resistance, reactance, impedance, admittance and the like of the secondary loops are calculated by measuring the voltage of the output signals, the amplitude of the current and the phase value between the amplitude and the phase value.
As shown in fig. 5, the insulation resistance measurement sampling circuit 120 generates a PWM waveform with adjustable frequency and duty ratio by using the controller 140, and the PWM waveform enters the step-up transformer after current amplification, and then the voltage is boosted by using the voltage-doubling rectifying circuit, so that a settable high-voltage dc voltage for measuring insulation resistance can be obtained. The voltage is connected to the two ends of the L and E of the insulation resistance to be tested, a voltage signal can be obtained by using a voltage division circuit, a current signal flowing through the insulation resistance to be tested can be obtained by using an operational amplifier for sampling, and the voltage and current signals are sent to the analog-to-digital conversion circuit 130. The controller 140 may calculate the insulation resistance using the analog-to-digital converted voltage-current signal.
All the above-mentioned measurements are realized through software control, and the tester only need insert binding post 20 with the wire, stirs suitable switch position, sets up test condition, then can accomplish insulating automated inspection between multiunit secondary circuit impedance test and the cable sinle silk by a key to will measurement result output at every turn, and can select to print.
It should be noted that the key points of the present embodiment are: 1. the direct current constant current source performs differential sampling research of direct current low resistance measurement; 2. research on measurement switching control of a controller driving function switch (relay); 3. research on the level of withstand voltage between the relay coil and the contact and withstand voltage at two ends when the contact is disconnected; 4. studies on the control of high voltage and measurements with a controller. The innovation points are as follows: 1. measuring direct current resistance by using a direct current constant current source, wherein the working current is 1A; 2. the relay is driven by the IO port of the microprocessor to control measurement switching, so that the measurement of the insulation resistance of the secondary circuit to the ground or any two secondary circuits is realized, and 3 or more measurement results are directly displayed on a screen and can be stored and printed.
The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.
Claims (7)
1. An automatic detector for protecting secondary circuit wiring is provided with a secondary circuit impedance test function and an insulation resistance test function between wire cores, and is characterized by comprising a shell, wherein a wiring terminal, a display, a micro printer and an operation key are arranged on the shell; wherein,
The display, the micro printer and the operation keys are respectively connected with the controller;
The input end of the input terminal is connected with the wiring terminal, and the output end of the input terminal is connected with the input end of the input switching circuit;
The input end of the impedance measurement sampling circuit is respectively connected with the output end of the input switching circuit and the output end of the sine inverter circuit, and the output end of the impedance measurement sampling circuit is connected with the controller through the analog-to-digital conversion circuit;
The input end of the insulation resistance measuring and sampling circuit is respectively connected with the output end of the input switching circuit and the output end of the direct-current high-voltage generating circuit, and the output end of the insulation resistance measuring and sampling circuit is connected with the controller through the analog-to-digital conversion circuit.
2. the automatic detector according to claim 1, further comprising a function switch driven by an IO port of the controller;
The function switch is arranged on the shell and between the input terminal and the input switching circuit and used for realizing the switching of the secondary loop impedance test function and the insulation resistance test function between the wire cores.
3. The automatic detector according to claim 1, wherein the number of the terminals is 16, the 16 terminals are divided into two rows, one row being equal to the other, and the terminals in each row are spaced apart from each other.
4. The automatic tester for protecting secondary circuit wiring according to claim 1, wherein the number of the operation buttons is 3, which are a test button, a print button and a set button.
5. the automatic detector for protecting the secondary circuit wiring according to claim 1, wherein the shell comprises a front shell and a rear shell which are detachable, an assembling groove is formed on the inner side of the side wall of the rear shell, and an assembling bump matched with the assembling groove is formed on the outer side of the side wall of the front shell;
The wiring terminal, the display, the micro printer and the operation keys are arranged on the front shell.
6. The automatic detector according to claim 1, wherein the display is an LCD display or an LED display.
7. the automatic detector of claim 1, wherein the controller is one of a central processing unit, a programmable logic controller, a single chip, or an embedded processor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920414925.9U CN209746065U (en) | 2019-03-29 | 2019-03-29 | Automatic detector for protecting secondary circuit wiring |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920414925.9U CN209746065U (en) | 2019-03-29 | 2019-03-29 | Automatic detector for protecting secondary circuit wiring |
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| CN209746065U true CN209746065U (en) | 2019-12-06 |
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| CN201920414925.9U Active CN209746065U (en) | 2019-03-29 | 2019-03-29 | Automatic detector for protecting secondary circuit wiring |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109765453A (en) * | 2019-03-29 | 2019-05-17 | 广东电网有限责任公司 | A kind of Protection secondary circuit wiring automatic tester |
| CN113176438A (en) * | 2021-04-15 | 2021-07-27 | 国网湖北省电力有限公司宜昌供电公司 | Transformer substation secondary circuit detector and detection method |
-
2019
- 2019-03-29 CN CN201920414925.9U patent/CN209746065U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109765453A (en) * | 2019-03-29 | 2019-05-17 | 广东电网有限责任公司 | A kind of Protection secondary circuit wiring automatic tester |
| CN113176438A (en) * | 2021-04-15 | 2021-07-27 | 国网湖北省电力有限公司宜昌供电公司 | Transformer substation secondary circuit detector and detection method |
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