CN211528600U - Circuit for testing oscillation wave - Google Patents
Circuit for testing oscillation wave Download PDFInfo
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- CN211528600U CN211528600U CN202020024678.4U CN202020024678U CN211528600U CN 211528600 U CN211528600 U CN 211528600U CN 202020024678 U CN202020024678 U CN 202020024678U CN 211528600 U CN211528600 U CN 211528600U
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Abstract
The application provides a circuit that vibrates ripples test carries out includes: the circuit comprises a rectifier diode, a first resistor, a first capacitor, a ball gap, an inductor and a voltage divider; the negative pole of the rectifier diode is a first connecting end connected with the high-voltage end of the alternating-current power supply circuit, the positive pole of the rectifier diode is connected with one end of a first resistor, the other end of the first resistor is connected with one end of a first capacitor and connected with one end of a ball gap, the other end of the first capacitor is a second connecting end connected with the low-voltage end of the alternating-current power supply circuit, the other end of the ball gap is connected with the input end of a voltage divider and connected with one end of an inductor, the other end of the inductor is a grounding end and connected with the second connecting end, the output end of the voltage divider is a first output end of a test result signal, and the grounding end of the voltage divider is a second output end of the. The circuit is simple in structure, the requirement of different tested products on the shock wave test can be met by the improved circuit, the expandability is good, and the test range is wide.
Description
Technical Field
The application relates to the field of electronic engineering, in particular to a circuit for testing oscillating waves.
Background
The existing oscillatory wave testing device is an integrated device developed for a specific type of tested products, and can only test a specific type of tested products, so that the testing range is single. And as the integrated equipment is adopted, technicians cannot see the internal structure and specific equipment parameters of the equipment, the internal structure is complex, the interior cannot be modified, and the flexibility and the expandability are not strong.
SUMMERY OF THE UTILITY MODEL
In view of this, the present application provides a circuit for performing oscillatory wave test, which can perform oscillatory wave test on a tested object such as an inductor and a cable, and select appropriate element parameters according to different types of tested objects, so as to meet the requirement of performing oscillatory wave test on different types of tested objects, and has the characteristics of simple structure, wide test range, and high expandability.
In order to achieve the purpose, the application provides the following technical scheme:
a circuit for conducting oscillatory wave testing, comprising: the circuit comprises a rectifier diode, a first resistor, a first capacitor, a ball gap, an inductor and a voltage divider; the negative electrode of the rectifier diode is a first connection end connected with the high-voltage end of the alternating-current power supply circuit, the positive electrode of the rectifier diode is connected with one end of the first resistor, the other end of the first resistor is connected with one end of the first capacitor and one end of the ball gap, the other end of the first capacitor is a second connection end connected with the low-voltage end of the alternating-current power supply circuit, the other end of the ball gap is connected with the input end of the voltage divider and one end of the inductor, the other end of the inductor is a grounding end and is connected with the second connection end, the output end of the voltage divider is a first test result signal output end, and the grounding end of the voltage divider is a second test result signal output end.
Optionally, in some optional embodiments, the circuit further includes: the ac power supply circuit includes: a voltage regulator and a transformer;
the primary side of the voltage regulator is an input side of an alternating current power supply, the secondary side of the voltage regulator is connected with the primary side of the transformer, the high-voltage end of the secondary side of the transformer is the high-voltage end of the alternating current power supply circuit, and the low-voltage end of the secondary side of the transformer is the low-voltage end of the alternating current power supply circuit.
Optionally, in some optional embodiments, the circuit further includes: and the fuse is arranged at the high-voltage end at the primary side of the voltage regulator.
Optionally, in some optional embodiments, the circuit further includes: a voltmeter and an ammeter;
the voltmeter is connected to two ends of the primary side of the transformer;
the ammeter is arranged on a line of a low-voltage end of the secondary side of the transformer.
Optionally, in some optional embodiments, the voltage divider includes: the circuit comprises a second capacitor, a third capacitor, a second resistor and a third resistor;
one end of the second capacitor is connected to one end of the third capacitor, and the other end of the second capacitor is connected to one end of the second resistor; the other end of the second resistor is connected to one end of the third resistor, the other end of the third resistor is connected to the other end of the third capacitor, a common end of the second capacitor and the second resistor is an input end of the voltage divider, a common end of the second capacitor and the third capacitor is an output end of the voltage divider, and a common end of the third capacitor and the third resistor is a ground end of the voltage divider.
Optionally, in some optional embodiments, the circuit further includes: and the other end of the filter is connected with one end of the filter, and the other end of the filter is the grounding end of the voltage divider.
Optionally, in some optional embodiments, the circuit further includes: and the first output end of the test result signal is connected with the first signal input end of the oscilloscope, and the second output end of the test result signal is connected with the second signal input end of the oscilloscope.
Optionally, in some optional embodiments, the circuit further includes: and one end of the inductor is connected with one end of one wire of the cable to be tested, the other end of the wire is suspended, and the other end of the inductor is connected with the second connecting end through the grounding metal layer of the cable to be tested.
According to the above scheme, the circuit for testing oscillating wave provided by the application comprises: the circuit comprises a rectifier diode, a first resistor, a first capacitor, a ball gap, an inductor and a voltage divider; the negative electrode of the rectifier diode is a first connection end connected with the high-voltage end of the alternating-current power supply circuit, the positive electrode of the rectifier diode is connected with one end of the first resistor, the other end of the first resistor is connected with one end of the first capacitor and one end of the ball gap, the other end of the first capacitor is a second connection end connected with the low-voltage end of the alternating-current power supply circuit, the other end of the ball gap is connected with the input end of the voltage divider and one end of the inductor, the other end of the inductor is a grounding end and is connected with the second connection end, the output end of the voltage divider is a first test result signal output end, and the grounding end of the voltage divider is a second test result signal output end. Therefore, the electric energy input by the alternating current power supply circuit can charge the first capacitor through the rectifier diode and the first resistor, when the voltage of the first capacitor rises to the specified voltage of the ball gap, the ball gap starts to be conducted, the first capacitor starts to discharge, the first capacitor and the inductor form an LC loop, LC oscillation occurs to generate oscillation waves, and the voltage of the oscillation waves generated by the LC oscillation is possibly large, so that the oscillation waves with high voltage can be converted into the oscillation waves with low voltage through the voltage divider, the oscillation waves can be collected conveniently, and the oscillation waves can be observed. The circuit is simple in structure, can select suitable element parameter transformation circuits according to different requirements of the tested products such as different inductors or cables for oscillating wave testing, meets the requirements of different tested products for oscillating wave testing, and is good in expandability and flexibility and wide in testing range.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.
Fig. 1 illustrates a circuit for performing an oscillatory wave test according to an embodiment of the present disclosure;
fig. 2 shows another circuit for performing oscillatory wave testing according to an embodiment of the present application;
FIG. 3 shows another circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 4 shows another circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 5 shows another exemplary circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 6 shows another exemplary circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 7 shows another circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 8 shows another circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
FIG. 9 shows another exemplary circuit for performing oscillatory wave testing according to an embodiment of the present disclosure;
fig. 10 shows a schematic cross-sectional view of a cable.
Detailed Description
The application discloses a circuit for testing oscillating waves, and a person skilled in the art can appropriately improve process parameters by referring to the content. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be included in the present application. While the structure and applications of this application have been described in terms of preferred embodiments, it will be apparent to those skilled in the art that the technology can be practiced and applied with modification, or with appropriate modification and combination, of the structures and applications described herein without departing from the spirit and scope of the application.
The existing oscillatory wave testing device is integrated and is a device developed aiming at a certain type of inductor or cable and other tested products, and the internal structure is complex. Therefore, the existing oscillatory wave testing device is difficult to modify according to the oscillatory wave testing requirements of different inductors or cables, the testing range is single, and the expandability and the flexibility are poor. Aiming at the problems, an oscillating wave test circuit can be designed, the circuit is simple in structure, and can generate oscillating waves and connect the oscillating waves to a tested product to test the oscillating waves of the tested product. The element of the circuit can be different according to the requirements of different tested products on the oscillatory wave test, and proper element parameters are selected to modify the circuit so as to meet the requirements of different tested products on the oscillatory wave test.
As shown in fig. 1, the present application provides a circuit for performing an oscillatory wave test, including: a rectifier diode D, a first resistor R1, a first capacitor C1, a ball gap G, an inductor L and a voltage divider W; a cathode of the rectifier diode D is a first connection terminal S1 connected to a high-voltage terminal of an ac power supply circuit, an anode of the rectifier diode D is connected to one terminal of the first resistor R1, the other terminal of the first resistor R1 is connected to one terminal of the first capacitor C1 and to one terminal of the ball gap G, the other terminal of the first capacitor C1 is a second connection terminal S2 connected to a low-voltage terminal of the ac power supply circuit, the other terminal of the ball gap G is connected to an input terminal P3 of the voltage divider W and to one terminal of the inductor L, the other terminal of the inductor L is a ground terminal and is connected to the second connection terminal S2, an output terminal P1 of the voltage divider W is a first output terminal of a test result signal, and an output terminal P2 of the voltage divider W is a second output terminal of the test result signal.
It should be understood that when it is required to test whether the turn-to-turn insulating layer of the inductor L is defective, the inductor L may be an inductor to be tested, and whether the turn-to-turn insulating layer of the inductor to be tested is defective may be detected through the present scheme. When it is necessary to test whether the insulation layer of the cable is defective, the inductance L referred to herein is an inductance with a defect-free known inter-turn insulation layer, and this scheme is not limited thereto.
It should be understood that the inductor L referred to herein may be one of three phases of an inductor, or may be an inductor L having only one phase, which is not limited in the present application. In practice, it is necessary to select an appropriate test method according to the specific situation.
It should be understood that the inductor without defects in the turn-to-turn insulating layer has a fixed inductance value within a specified range of voltage applied across the inductor, i.e., within an allowable test voltage range, and does not change with voltage changes. If the turn-to-turn insulation layer of the inductor L is defective, but the inductor L does not break down at a low voltage, when the voltage rises to a certain level, the inductor L may break down, thereby causing a change in the inductance value. Therefore, according to the calculation formula of the frequency of the oscillation wave generated by the LC oscillation:
if the frequency changes, the tested inductance value changes, namely the inductance L has turn-to-turn short circuit.
In the actual test process, different voltages can be applied to two ends of the same inductor L for two times respectively, oscillation wave waveforms under different voltages are recorded respectively, and whether the frequency of the waveforms of the two times changes or not is compared. Three situations may be encountered in practical testing, as follows:
the first case is that the inter-turn insulation of the inductor L has some defects, but the inductor L may not break down at the first applied low test voltage, i.e. the first obtained oscillation waveform is close to the oscillation waveform obtained at the low test voltage when the inter-turn insulation of the inductor L is defect-free. And applying high test voltage for the second time to cause the inductor L to break down, so that the inductance value of the inductor L is obviously changed, and the frequency of the oscillation wave waveform obtained for the second time is different from the frequency of the oscillation wave waveform obtained for the first time, thereby indicating that the turn-to-turn insulating layer of the inductor L has defects, even if the defects exist, the inductor L can be tested, and the test result is better.
Optionally, the inductor L in the first case may be an inductor having only one phase, or may be one phase of a three-phase inductor, which is not limited in this application.
The second case is that the inter-turn insulating layer of the inductor L itself has only one phase without defects, and the inductance value will be fixed, that is, the waveform of the oscillating wave obtained by applying the low test voltage for the first time and the waveform of the oscillating wave obtained by applying the high test voltage for the second time are relatively close to or consistent, that is, the frequency is not changed, so that the case that the inter-turn insulating layer of the inductor L has no defects can be tested.
Optionally, for an inductor L having only one phase, if the inductor L is broken down before the test or the inter-turn insulating layer itself has no defect, the attenuation period of the oscillation wave of the inductor L to be tested may be calculated by combining the parameters of the inductor L to be tested and the circuit parameters, and whether the attenuation periods of the two oscillation wave waveforms obtained by the circuit test are close to the calculated attenuation period may be determined by combining the calculated attenuation period, if yes, it is determined that the inter-turn insulating layer of the inductor L to be tested has no defect, and if the difference is large, it is determined that the inductor L to be tested itself has broken down.
In the third case, when the three-phase inductor is tested, the inductor L in the circuit is one phase of the three-phase inductor, and two oscillation wave waveforms of each phase under different voltages can be respectively tested, and if the two oscillation wave waveforms of each phase are similar and the oscillation wave waveforms of the three phases are similar, whether the inter-turn insulation layers of the three phases of the tested inductor are defective or not can be determined according to the method in the second case; if the two oscillation waveforms of each phase are similar and the oscillation waveform of at least one phase is different from the other two oscillation waveforms, it can be determined that the inter-turn insulating layer of the phase with the slowest attenuation of the oscillation waveform has no defect, and the breakdown of the phase corresponding to the oscillation waveform with the obviously faster attenuation is compared with the oscillation waveform of the phase with the defect-free inter-turn insulating layer.
The rectifying diode D may rectify the ac power output from the ac power supply circuit into dc power, so that the first capacitor C1 may be charged and discharged. For example, after the first capacitor C1 is charged to the dc voltage required by the oscillatory wave test, the ball gap G is turned on, and the first capacitor C1 forms LC oscillation through the ball gap G and the inductor L, so as to generate the oscillatory wave required by the test.
Optionally, when the first capacitor C1 is selected, a capacitor meeting the test requirement needs to be selected according to the voltage and current required for performing the oscillatory wave test, for example, the charging voltage and the capacitance of the first capacitor C1 should meet the requirement for performing the oscillatory wave test.
Optionally, other rectifying elements may be used to replace the rectifying diode D, and the selected rectifying diode D or rectifying element needs to meet the voltage and current requirements required for the oscillatory wave test.
The first resistor R1 can control the charging time of the first capacitor C1, and as can be seen from the time constant τ RC, the resistance of the first resistor R1 is different, and accordingly the charging time of the first capacitor C1 is also different, so that the first resistor R1 with different resistance values can be selected according to the actual need of performing the oscillatory wave test. Of course, the first resistor R1 may also be a variable resistor, and the charging time of the first capacitor C1 can be changed by directly adjusting the resistance value of the variable resistor.
The first resistor R1 can also limit the short-circuit current when the inductor L breaks down, protecting the rectifier diode D.
Optionally, the resistance of the first resistor R1 should satisfy the requirements of the charging time and the current required for the oscillatory wave test.
The ball gap G is a standard discharge element, and the discharge voltage of the ball gap G may be constant under a certain temperature, humidity, and pressure.
Optionally, the oscillation wave generated by LC oscillation may be a high-voltage oscillation wave, and since the cost of directly acquiring the high-voltage oscillation wave is high and the difficulty is high, the high-voltage oscillation wave may be converted into a low-voltage oscillation wave according to a certain ratio through the voltage divider W, so as to acquire the oscillation wave.
Can exert twice to inductance L and vibrate the ripples, first time voltage is lower and second time voltage is higher, because vibrate inductance value and capacitance value in the ripples testing process and be fixed unchangeable twice, so vibrate frequency twice
That is, the wavelength is fixed and unchanged, if the frequency is changed in the two tests, the inductance value is changed in the test, that is, the inductor L is subjected to turn-to-turn short circuit, that is, the turn-to-turn insulating layer of the inductor L is defective. In order to prevent the turn-to-turn insulation damage of the inductor under a lower voltage, when the oscillatory wave test is carried out, the voltage of the oscillatory wave applied for the first time can be 20% of the experimental voltage specified by the inductor L, and the voltage can be used as a calibration voltage and the waveform is recorded; the second time of the oscillation wave voltage applied to the two ends of the inductor L may be an experimental voltage with a voltage higher than the calibration voltage, and a waveform is obtained, the waveform of the oscillation wave with the calibration voltage applied to the two ends of the inductor L and the waveform of the oscillation wave with the experimental voltage are compared, if the frequencies of the two waveforms are consistent, it is determined that the turn-to-turn insulating layer of the inductor L is defect-free, and if the frequencies of the two waveforms are inconsistent, it is determined that the turn-to-turn insulating layer of the inductor L is defect-free.
Optionally, an oscilloscope can be used for recording waveforms obtained under different oscillating wave voltages, and whether the frequency of the oscillating wave changes can be known by observing whether the wave crests and the wave troughs of the two waveforms are shifted or not on the oscilloscope; if the displacement does not occur, the frequency of the oscillating wave is not changed, and if the displacement occurs, the frequency of the oscillating wave is changed.
As shown in fig. 2, optionally, in some optional embodiments, the circuit further includes: the ac power supply circuit includes: a voltage regulator T1 and a transformer T2;
a primary side of the voltage regulator T1 is an ac power input side, a secondary side of the voltage regulator T1 is connected to a primary side of the transformer T2, a high-voltage terminal of the secondary side of the transformer T2 is a high-voltage terminal of the ac power circuit, and a low-voltage terminal of the secondary side of the transformer T2 is a low-voltage terminal of the ac power circuit.
The primary side of the voltage regulator T1 can be connected to an ac power supply, and the voltage value output from the secondary side of the voltage regulator T1 can be changed by adjusting the voltage regulator T1, so that the voltage value can be linearly changed. Of course, other voltage regulating devices may be used in place of voltage regulator T1.
The transformer T2 may boost the test voltage, and change the voltage of the high side of the transformer T2 by changing the voltage of the low side of the transformer T2 according to the transformer voltage ratio. Of course, other voltage boosting devices may be used in place of transformer T2.
The voltage regulator T1 is matched with the transformer T2, the voltage regulator T1 can be adjusted according to different test requirements, the voltage is boosted through the transformer T2, the voltage meeting the test requirements is obtained, and the voltage adjusting range is large.
As shown in fig. 3, optionally, in some optional embodiments, the circuit further includes: and a fuse FU provided at a high voltage side of the primary side of the voltage regulator T1.
Fuse FU is an overcurrent protection device that blows out a fuse by heat generated from the fuse when a current exceeds a predetermined value, thereby cutting off the connection between a power supply and a test circuit and powering off the test circuit.
Optionally, a fuse FU with a specified value about 1.2 times the maximum test current of the test circuit is generally selected, and of course, other overcurrent protection devices may be used instead of the fuse FU, for example, an overcurrent relay may be used instead.
As shown in fig. 4, optionally, in some optional embodiments, the circuit further includes: a voltmeter V and an ammeter A;
the voltmeter V is connected to both ends of the primary side of the transformer T2;
the ammeter a is provided in a line of a low-voltage terminal on the secondary side of the transformer T2.
Voltmeter V can measure the voltage of the test circuit, ammeter a can measure the current of the test circuit, and voltage regulator T1 can be adjusted according to the measured voltage and current, so that the voltage and current of the test circuit meet different test requirements. For example, the voltage of the first oscillatory wave test may be 20% of the experimental voltage specified by the inductor L, and then the voltage regulator T1 may be directly adjusted and the indication of the voltmeter V may be observed, so as to accurately adjust the voltage of the first oscillatory wave test to be 20% of the experimental voltage specified by the inductor L. Similarly, the indication of the voltmeter V can be referred to for adjustment during the second oscillatory wave test, so that the oscillatory wave voltage can be accurately adjusted to the target voltage, the test process can be accurately controlled, and the test result is reliable.
As shown in fig. 5, optionally, in some optional embodiments, the voltage divider W includes: the second capacitor C2, the third capacitor C3, the second resistor R2 and the third resistor R3;
one end of the second capacitor C2 is connected to one end of the third capacitor C3, and the other end of the second capacitor C2 is connected to one end of the second resistor R2; the other end of the second resistor R2 is connected to one end of the third resistor R3, the other end of the third resistor R3 is connected to the other end of the third capacitor C3, the common end between the second capacitor C2 and the second resistor R2 is the input end P3 of the voltage divider W, the common end between the second capacitor C2 and the third capacitor C3 is the output end P1 of the voltage divider W, and the common end between the third capacitor C3 and the third resistor C3 is the ground end P2 of the voltage divider W.
The ratio of the voltage across the second capacitor C2 to the voltage across the third capacitor C3 of the voltage divider W is: c1+ C2/C1, so that the high-voltage oscillation wave can be converted into the low-voltage oscillation wave for acquisition.
As shown in fig. 6, optionally, the output terminal P1 of the voltage divider W may also be connected to the common terminal of the second capacitor C2 and the third capacitor C3, and to the common terminal of the second resistor R2 and the third resistor R3. Therefore, the direct current waveform and the alternating current waveform can be collected, and the applicability is better.
As shown in fig. 7, optionally, in some optional embodiments, the circuit further includes: and a filter F having one end connected to the other end of the third capacitor C3, and the other end of the filter F being a ground terminal P2 of the voltage divider W.
The filter F may filter out glitches in the waveform so that the acquired waveform is smoother for viewing the acquired waveform.
As shown in fig. 8, optionally, in some optional embodiments, the circuit further includes: and the first output end of the test result signal is connected with the first signal input end of the oscilloscope O, and the second output end of the test result signal is connected with the second signal input end of the oscilloscope O.
The oscilloscope O may generally have two channels, and may select the anode of any one channel to be connected to the output terminal of the voltage divider W, and connect the cathode of the channel to the ground terminal of the voltage divider W.
Optionally, an oscilloscope O may be used to store the waveform obtained under the first test voltage; and performing a second test, wherein the voltage of the second test can be different from the voltage of the first test. Comparing whether the frequency of the waveform obtained by different test voltages is the same or not, and if so, indicating that the turn-to-turn insulating layer of the tested inductor L or the insulating layer of the cable has no defect; if the measured inductance L is different, the turn-to-turn insulating layer of the measured inductance L or the insulating layer of the cable is defective, so that the measured inductance L or the cable breaks down, and the waveform frequencies are different.
As shown in fig. 9, optionally, in some optional embodiments, the circuit further includes: and one end of the inductor L is connected with one end of one wire of the cable to be tested, the other end of the wire is suspended, and the other end of the inductor L is connected with the second connecting end S2 through the ground metal layer of the cable to be tested.
It should be understood that the present solution can detect whether the insulation layer of the cable is defective, in addition to detecting whether the turn-to-turn insulation layer of the inductor L is defective. The circuit can be used for testing the oscillating wave of the cable, for example, the cable to be tested can be connected with the inductor L with a known defect-free interturn insulating layer and then connected to the position of the inductor L in the circuit, so that whether the frequency of the oscillating wave changes under the condition of different voltages after the cable is connected to a loop is tested.
It should be understood that if the insulation layer of the cable is defective, it may cause the equivalent capacitance of the cable to break down at a low voltage and at a high voltage, so that the capacitance of the cable changes according to the formula
It can be known that, under the condition that the inductance value is not changed, the change of the capacitance value can cause the change of the frequency of the tested oscillating wave waveform, that is, the defect of the insulation layer of the cable can be tested.
Optionally, the cable to be tested is connected with the inductor L with a known defect-free inter-turn insulating layer, and in practice, the connection is required according to the actual condition of the cable. For example, the cable may have three items, yellow, green and red, and each item may be tested separately twice while the cable is being tested, and the test voltages of the two times may be different.
In the testing method, one end of the first line may be connected to one end of the inductor L without defects in the known inter-turn insulating layer, as shown in fig. 10, a certain line in the figure may be any one of the three lines, for example, yellow line, and one end of the yellow line may be connected to one end of the inductor L without defects in the known inter-turn insulating layer, that is, the inductor L in fig. 9 is the inductor L without defects in the known inter-turn insulating layer, the other end of the yellow line is floating, the other end of the inductor L is connected to the input terminal P3 of the voltage divider W, and the ground metal layer of the cable to be tested where the yellow line is located is connected to the ground terminal of the first capacitor C1. The specific test procedure is substantially the same as that of the inductor L. The difference is that if the insulating layer of one item of the cable is broken down, the tester may be difficult to judge by naked eyes, that is, if the frequencies of the oscillating wave waveforms obtained by two tests of one item of the cable are consistent or close, it cannot be determined whether the item is broken down or the insulating layer of the item has no defect. If the frequencies of the two oscillatory wave waveforms obtained by the green term are also consistent or similar, whether the frequencies of the oscillatory wave waveforms of the yellow term are consistent with the frequencies of the oscillatory wave waveforms of the green term or not can be compared, and if the frequencies of the two oscillatory wave waveforms obtained by the red term are not consistent, the insulating layer of one of the yellow term and the green term is defective is indicated.
In summary, for a certain term, it can be determined that the insulating layer of the term is defective according to the change of the oscillation wave frequency under different voltages. The method for judging whether a certain insulating layer in the cable is defective or not can be obtained by comparing the waveforms of the three oscillating waves in pairs for the whole cable, and a three-phase inductance judgment method can be referred specifically, wherein the cable judgment method is similar to the three-phase inductance judgment method.
In conclusion, the scheme can detect whether the turn-to-turn insulating layer of the inductor L is defective or not, and can also detect whether the insulating layer of each item of the cable is defective or not. The problem that in actual engineering, when an engineer accesses an inductor L or a cable in a circuit, the voltage is small at the beginning, so that the inductor with the defective turn-to-turn insulating layer or the cable with the defective insulating layer is not broken down, and the engineer cannot find potential safety hazards in time is avoided. When the voltage at the two ends of the cable with the defective inductor or the defective insulating layer in the turn-to-turn insulating layer in a certain period rises to a certain degree, the cable with the defective inductor or the defective insulating layer in the turn-to-turn insulating layer is broken down, the normal operation of a circuit is influenced, when the faults occur, a large amount of manpower and material resources are needed to be spent to check and remove the faults, the cost is high, the potential safety hazards can be accurately tested, and the later maintenance cost is saved.
The foregoing is only a preferred embodiment of the present application and it should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.
Claims (8)
1. A circuit for performing oscillatory wave testing, comprising: the circuit comprises a rectifier diode, a first resistor, a first capacitor, a ball gap, an inductor and a voltage divider; the negative electrode of the rectifier diode is a first connecting end connected with the high-voltage end of the alternating-current power supply circuit, the positive electrode of the rectifier diode is connected with one end of a first resistor, the other end of the first resistor is connected with one end of a first capacitor and one end of a ball gap, the other end of the first capacitor is a second connecting end connected with the low-voltage end of the alternating-current power supply circuit, the other end of the ball gap is connected with the input end of the voltage divider and one end of an inductor, the other end of the inductor is a grounding end and is connected with the second connecting end, the output end of the voltage divider is a first test result signal output end, and the grounding end of the voltage divider is a second test result signal output end.
2. The circuit of claim 1, further comprising: the alternating current power supply circuit, alternating current power supply circuit includes: a voltage regulator and a transformer;
the primary side of the voltage regulator is an alternating current power supply input side, the secondary side of the voltage regulator is connected with the primary side of the transformer, the high-voltage end of the secondary side of the transformer is the high-voltage end of the alternating current power supply circuit, and the low-voltage end of the secondary side of the transformer is the low-voltage end of the alternating current power supply circuit.
3. The circuit of claim 2, further comprising: and the fuse is arranged at the high-voltage end of the primary side of the voltage regulator.
4. The circuit of claim 2, further comprising: a voltmeter and an ammeter;
the voltmeter is connected to two ends of the primary side of the transformer;
and the low-voltage end of the secondary side of the transformer is provided with the ammeter on a line.
5. The circuit of claim 1, wherein the voltage divider comprises: the circuit comprises a second capacitor, a third capacitor, a second resistor and a third resistor;
one end of the second capacitor is connected with one end of the third capacitor, and the other end of the second capacitor is connected with one end of the second resistor; the other end of the second resistor is connected with one end of the third resistor, the other end of the third resistor is connected with the other end of the third capacitor, the common end of the second capacitor and the second resistor is the input end of the voltage divider, the common end of the second capacitor and the third capacitor is the output end of the voltage divider, and the common end of the third capacitor and the third resistor is the grounding end of the voltage divider.
6. The circuit of claim 5, further comprising: and the other end of the third capacitor is connected with one end of the filter, and the other end of the filter is the grounding end of the voltage divider.
7. The circuit of claim 1, further comprising: and the first output end of the test result signal is connected with the first signal input end of the oscilloscope, and the second output end of the test result signal is connected with the second signal input end of the oscilloscope.
8. The circuit of claim 1, further comprising: and one end of the inductor is connected with one end of one wire of the cable to be tested, the other end of the wire is suspended, and the other end of the inductor is connected with the second connecting end through a grounding metal layer of the cable to be tested.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020024678.4U CN211528600U (en) | 2020-01-07 | 2020-01-07 | Circuit for testing oscillation wave |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020024678.4U CN211528600U (en) | 2020-01-07 | 2020-01-07 | Circuit for testing oscillation wave |
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| CN211528600U true CN211528600U (en) | 2020-09-18 |
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| CN202020024678.4U Active CN211528600U (en) | 2020-01-07 | 2020-01-07 | Circuit for testing oscillation wave |
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| CN (1) | CN211528600U (en) |
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