CN113252990A - Cable dielectric loss testing device - Google Patents
Cable dielectric loss testing device Download PDFInfo
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- CN113252990A CN113252990A CN202110439360.1A CN202110439360A CN113252990A CN 113252990 A CN113252990 A CN 113252990A CN 202110439360 A CN202110439360 A CN 202110439360A CN 113252990 A CN113252990 A CN 113252990A
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2688—Measuring quality factor or dielectric loss, e.g. loss angle, or power factor
- G01R27/2694—Measuring dielectric loss, e.g. loss angle, loss factor or power factor
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Abstract
The application relates to a cable dielectric loss testing device. The device comprises: the device comprises a shielding assembly, a signal generation module, an interference test module and a dielectric loss test module; the signal generating module is used for providing a test signal for the cable to be tested; the shielding assembly is arranged on the cable to be tested and used for outputting an interference electric signal on a protective layer of the cable to be tested; the interference test module is used for collecting an interference electric signal output by the shielding component and transmitting the interference electric signal to the dielectric loss test module; the dielectric loss test module is used for collecting the test signal output by the signal generation module and determining the dielectric loss value of the cable to be tested according to the test signal and the interference electric signal. By adopting the method, the interference electric signals on the cable sheath to be tested can be equivalent when the dielectric loss test is carried out on the cable to be tested, and the influence brought by the interference electric signals is removed when the dielectric loss value is calculated, so that the dielectric loss value is more accurate.
Description
Technical Field
The application relates to the technical field of power systems, in particular to a cable dielectric loss testing device.
Background
Power cables are increasingly used in power distribution networks due to their good insulation strength and mechanical properties. However, because the operating environment of some cables in the distribution network is severe, when the service life is long, the cables may have the defects of aging, inlet water wetting, partial discharge and the like, and the normal operation is affected. Therefore, dielectric loss experiments, partial discharge experiments, etc. need to be performed on the cable to ensure the normal use of the cable in the distribution network.
In the prior art, when a dielectric loss experiment is performed on a cable, voltage is applied to the cable, and the dielectric loss value of the cable is calculated by measuring the voltage and the current of the cable. However, the prior art has the problem of inaccurate dielectric loss test.
Disclosure of Invention
Therefore, it is necessary to provide a cable dielectric loss testing apparatus capable of accurately testing the dielectric loss value of the cable to be tested in view of the above technical problems.
A cable dielectric loss testing apparatus, the apparatus comprising:
the device comprises a shielding assembly, a signal generation module, an interference test module and a dielectric loss test module;
the signal generating module is used for providing a test signal for the cable to be tested;
the shielding assembly is arranged on the cable to be tested and used for outputting an interference electric signal on a protective layer of the cable to be tested;
the interference test module is used for collecting the interference electric signals output by the shielding assembly and transmitting the interference electric signals to the dielectric loss test module;
and the dielectric loss test module is used for acquiring the test signal output by the signal generation module and determining the dielectric loss value of the cable to be tested according to the test signal and the interference electric signal.
In one embodiment, the shielding assembly comprises a shielding ring and a first resistor, the shielding ring is installed on the cable to be tested, one end of the first resistor is connected with the shielding ring, and the other end of the first resistor is grounded;
and the interference test module is used for acquiring the electric signal on the first resistor as an interference electric signal.
In one embodiment, the interference electrical signal is a high-voltage side electrical signal, and the interference test module comprises: an interference signal acquisition unit and an isolation unit; wherein the content of the first and second substances,
the interference signal acquisition unit is used for acquiring the low-voltage side electric signal on the first resistor and transmitting the low-voltage side electric signal on the first resistor to the isolation unit;
and the isolation unit is used for converting the low-voltage side electric signal on the first resistor into a high-voltage side electric signal and transmitting the converted high-voltage side electric signal to the dielectric loss test module.
In one embodiment, an isolation unit includes: the device comprises a signal modulation circuit, an electro-optical conversion circuit, an optical fiber, a photoelectric conversion circuit and a signal demodulation circuit;
the signal modulation circuit is used for modulating the low-voltage side electric signal on the first resistor into an electric signal which can be transmitted by an optical fiber;
the electro-optical conversion circuit is used for converting the electric signal which can be transmitted by the optical fiber into an optical signal and transmitting the optical signal to the photoelectric conversion circuit through the optical fiber;
the photoelectric conversion circuit is used for converting the optical signal into a high-voltage side electric signal;
and the signal demodulation circuit is used for demodulating the high-voltage side electric signal and transmitting the demodulated high-voltage side electric signal to the dielectric loss test module.
In one embodiment, the interference test module further comprises: a power adapter; the input end of the power adapter is connected with a first power supply; the output end of the power adapter is connected with the interference signal acquisition unit;
and the power adapter is used for supplying power to the interference signal acquisition unit according to the electric energy provided by the first power supply.
In one embodiment, the signal generating module comprises: the high-voltage generator, the resistor divider and the second resistor; the first output end of the high-voltage generator is respectively connected with one end of the resistor voltage divider and one end of the second resistor; the second output end of the high-voltage generator, the other end of the cable to be tested and the other end of the resistance voltage divider are all grounded; the other end of the second resistor is connected with one end of the cable to be tested; the dielectric loss testing module is respectively connected with two ends of the resistance voltage divider; the dielectric loss testing module is respectively connected with two ends of the second resistor;
the high voltage generator is used for providing input voltage for the cable to be tested;
and the dielectric loss test module is used for respectively acquiring the voltage of the resistance voltage divider and the voltage of the second resistor, and determining the dielectric loss value of the cable to be tested according to the voltage of the resistance voltage divider, the voltage of the second resistor and the interference electric signal.
In one embodiment, the resistor divider comprises: a third resistor and a fourth resistor; one end of the third resistor is respectively connected with the first output end of the high-voltage generator and one end of the second resistor; the other end of the third resistor is connected with one end of the fourth resistor; the other end of the fourth resistor is grounded; the dielectric loss testing module is connected with two ends of the third resistor;
and the dielectric loss testing module is used for acquiring the voltage on the third resistor as the voltage of the resistor voltage divider.
In one embodiment, the resistance of the fourth resistor is greater than the resistance of the third resistor, and the difference between the resistance of the fourth resistor and the resistance of the third resistor is greater than the predetermined resistance threshold.
In one embodiment, the apparatus further comprises: a second power supply;
and the second power supply is used for supplying power to the dielectric loss test module.
In one embodiment, the high voltage generator is a 0.1Hz ultra low frequency high voltage generator.
Above-mentioned cable is situated between and is decreased testing arrangement because cable is situated between and is decreased testing arrangement includes: the device comprises a shielding assembly, a signal generation module, an interference test module and a dielectric loss test module; the signal generating module provides a test signal for the cable to be tested; the shielding assembly is arranged on the cable to be tested and outputs an interference electric signal on a protective layer of the cable to be tested; the interference test module collects interference electric signals output by the shielding assembly and transmits the interference electric signals to the dielectric loss test module; the dielectric loss test module collects the test signal output by the signal generation module and determines the dielectric loss value of the cable to be tested according to the test signal and the interference electric signal. Can be when the cable that awaits measuring is situated between and decreases the test, with the interference signal of telecommunication equivalence on the cable sheath that awaits measuring to get rid of the influence that the interference signal of telecommunication brought when calculating the situated between and decrease the value, make the situated between decrease the value more accurate, simultaneously, can be no matter whether the sheath of the cable that awaits measuring can open when carrying out ground connection, the homoenergetic measures the interference signal of telecommunication, realizes calculating the cable that awaits measuring situated between and decreases the value accurately.
Drawings
FIG. 1 is a block diagram of a cable dielectric loss testing apparatus according to an embodiment;
FIG. 2 is a schematic diagram of dielectric loss measurement parameters in one embodiment;
FIG. 3 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
FIG. 4 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
FIG. 5 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
FIG. 6 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
FIG. 7 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
FIG. 8 is a block diagram of an embodiment of a cable dielectric loss testing apparatus;
fig. 9 is a block diagram of another cable dielectric loss testing apparatus according to an embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
The numbering of the components as such, for example "first", "second", etc., in this application is used solely to distinguish between the objects depicted and not to imply any order or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings). In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present application and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be considered as limiting the present application.
In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In one embodiment, fig. 1 is a block diagram of a cable dielectric loss testing apparatus, and as shown in fig. 1, there is provided a cable dielectric loss testing apparatus, including: the device comprises a shielding component 11, a signal generating module 12, an interference testing module 13 and a dielectric loss testing module 14;
the signal generating module 12 is used for providing a test signal for the cable 15 to be tested;
the shielding component 11 is arranged on the cable 15 to be tested and used for outputting an interference electric signal on a protective layer of the cable to be tested;
the interference test module 13 is used for collecting the interference electric signals output by the shielding component 11 and transmitting the interference electric signals to the dielectric loss test module 14;
and the dielectric loss testing module 14 is configured to collect the testing signal output by the signal generating module 11, and determine a dielectric loss value of the cable to be tested according to the testing signal and the interference electrical signal.
Specifically, the signal generation module can receive an electrical signal provided by the direct-current power supply, and after the electrical signal is boosted or reduced in voltage, the electrical signal is transmitted to the cable to be tested, so that a dielectric loss test is performed on the cable to be tested. In an example, when the dielectric loss test is performed on the cable to be tested, the signal generation module may convert the electrical signal provided by the dc power supply into an electrical signal 0.5 times, 1.0 times, or 1.5 times of the rated voltage of the cable to be tested, and transmit the electrical signal to the cable to be tested. The electrical signal provided by the dc power source may include an electrical signal with a voltage of 220V.
The shielding component is arranged on the cable to be detected, leads out the electric signal flowing through the protective layer of the cable to be detected and outputs the interference electric signal on the protective layer of the cable to be detected. The interference electrical signal may be a voltage signal of the shielding assembly, or may be a current signal of the shielding assembly, which is not limited herein.
The interference test module is connected with the shielding assembly, can collect interference electric signals on the shielding assembly and transmits the interference electric signals to the dielectric loss test module. The interference test module can be a current transformer and directly collects the current of the shielding component; the voltage acquisition circuit can also be used for acquiring the voltage of the shielding component.
And the dielectric loss test module is used for acquiring the test signal output by the signal generation module and the interference current signal of the interference test module and determining the dielectric loss value of the cable to be tested according to the test signal and the interference current signal. The test signal may include a working voltage signal and a working current signal output by the signal generation module, and the test signal is a vector signal. For example, as shown in fig. 2, the dielectric loss test module first subtracts the interference electrical signal I2 from the working current signal I in the test signal to obtain a real current signal I1 of the cable to be tested, and performs vector calculation on the working voltage signal U in the test signal and the I1 to obtain a dielectric loss value, where the dielectric loss value is tan (90- θ), and θ is a phase angle between I1 and U.
In this embodiment, because cable dielectric loss testing arrangement includes: the device comprises a shielding assembly, a signal generation module, an interference test module and a dielectric loss test module; the signal generating module provides a test signal for the cable to be tested; the shielding assembly is arranged on the cable to be tested and outputs an interference electric signal on a protective layer of the cable to be tested; the interference test module collects interference electric signals output by the shielding assembly and transmits the interference electric signals to the dielectric loss test module; the dielectric loss test module collects the test signal output by the signal generation module and determines the dielectric loss value of the cable to be tested according to the test signal and the interference electric signal. Can be when the cable that awaits measuring is situated between and decreases the test, with the interference signal of telecommunication equivalence on the cable sheath that awaits measuring to get rid of the influence that the interference signal of telecommunication brought when calculating the situated between and decrease the value, make the situated between decrease the value more accurate, simultaneously, can be no matter whether the sheath of the cable that awaits measuring can open when carrying out ground connection, the homoenergetic measures the interference signal of telecommunication, realizes calculating the cable that awaits measuring situated between and decreases the value accurately.
In the foregoing embodiment, the cable dielectric loss test module is described, in which the shielding assembly can output an interference electrical signal of a cable to be tested, and now, an embodiment further describes the shielding assembly, in an embodiment, as shown in fig. 3, the shielding assembly 11 includes a shielding ring 111 and a first resistor 112, the shielding ring 111 is installed on the cable 15 to be tested, one end of the first resistor 112 is connected to the shielding ring 111, and the other end of the first resistor 112 is grounded;
and the interference test module 13 is used for acquiring the electric signal on the first resistor 112 as an interference electric signal.
Specifically, the grounding end of the signal generation module is a low-voltage end and is connected with the sheath of the cable to be tested, and the non-grounding end of the signal generation module is a high-voltage end and is connected with the core wire of the cable to be tested. The shielding ring is installed on the cable to be tested and used for leading out the electric signal flowing through the protective layer of the cable to be tested before the cable to be tested receives the electric signal provided by the direct-current power supply converted by the signal generating module, outputting an interference electric signal on the protective layer of the cable to be tested, facilitating measurement of the interference electric signal, connecting the first resistor behind the shielding ring, and taking the electric signal on the first resistor as the interference electric signal. The interference test module can collect a voltage signal on the first resistor as an interference electric signal, and also can collect a current signal of the first resistor as an interference electric signal, and transmits the interference electric signal to the dielectric loss test module. Wherein the shield ring may comprise a metal ring.
In this embodiment, the shielding assembly includes a shielding ring and a first resistor, the shielding ring is installed on the cable to be tested, one end of the first resistor is connected to the shielding ring, and the other end of the first resistor is grounded; the interference test module collects the electric signal on the first resistor as an interference electric signal. The interference electric signal of the cable sheath to be measured can be led out and equivalent measurement is carried out, and then the interference electric signal is removed to obtain an accurate dielectric loss value when the dielectric loss value is calculated.
The foregoing embodiment describes the shielding assembly, and after the interference testing module acquires the interference electrical signal, the interference electrical signal needs to be transmitted to the dielectric loss testing module, and now an embodiment describes how to transmit the interference electrical signal to the dielectric loss testing module, in an embodiment, as shown in fig. 4, the interference electrical signal is a high-voltage side electrical signal, and the interference testing module 13 includes: an interference signal acquisition unit 131 and an isolation unit 134; wherein the content of the first and second substances,
the interference signal acquisition unit 131 is used for acquiring the low-voltage side electric signal on the first resistor and transmitting the low-voltage side electric signal on the first resistor to the isolation unit;
and the isolation unit 132 is configured to convert the low-voltage-side electrical signal on the first resistor into a high-voltage-side electrical signal, and transmit the converted high-voltage-side electrical signal to the dielectric loss test module.
Specifically, because the one end ground connection of first resistance among the shielding component, it is in the low pressure side, consequently, what the interfering signal acquisition unit gathered is that the signal of telecommunication of first resistance is the low pressure side signal of telecommunication, but the dielectric loss test module is located the high pressure side of signal generation module output, and the low pressure side signal of telecommunication can not direct transmission to the dielectric loss test module of high pressure side, and at this moment, need pass through the isolation unit, convert the low pressure side signal of telecommunication, convert the signal of telecommunication that the high pressure side can receive into, interfering signal of telecommunication promptly. Wherein, the interference signal acquisition unit may include: a voltage transformer, a current transformer, etc., without limitation.
Alternatively, the isolation unit 132 may include a photoelectric isolation unit. Further, as shown in fig. 5, the optoelectronic isolation unit includes: a signal modulation circuit 1321, an electro-optical conversion circuit 1322, an optical fiber 1323, an optical-electrical conversion circuit 1324, and a signal demodulation circuit 1325; the signal modulation circuit is used for modulating the low-voltage side electric signal on the first resistor into an electric signal which can be transmitted by an optical fiber; the electro-optical conversion circuit is used for converting the electric signal which can be transmitted by the optical fiber into an optical signal and transmitting the optical signal to the photoelectric conversion circuit through the optical fiber; the photoelectric conversion circuit is used for converting the optical signal into a high-voltage side electric signal; and the signal demodulation circuit is used for demodulating the high-voltage side electric signal and transmitting the demodulated high-voltage side electric signal to the dielectric loss test module.
In this embodiment, since the interference electrical signal is a high-voltage side electrical signal, the interference test module includes: an interference signal acquisition unit and an isolation unit; the interference signal acquisition unit acquires low-voltage side electric signals on the first resistor and transmits the low-voltage side electric signals on the first resistor to the isolation unit; the isolation unit converts the low-voltage side electric signal on the first resistor into a high-voltage side electric signal and transmits the converted high-voltage side electric signal to the dielectric loss testing module. Can be with the low pressure side signal of telecommunication conversion on the interference test module collection first resistance for the high pressure side and cut the signal of telecommunication that decreases test module can receive, and then realize when the dielectric loss test module calculates the dielectric loss value, get rid of the interference influence that interference signal brought, and then obtain comparatively accurate dielectric loss value.
The foregoing embodiment describes the interference testing module, and when the interference testing module normally works, the interference testing module needs to be powered on, and now an embodiment describes the interference testing module, and in an embodiment, as shown in fig. 6, the interference testing module 13 further includes: a power adapter 133; the input end of the power adapter 131 is connected to a first power supply; the output end of the power adapter is connected with the interference signal acquisition unit 131;
and a power adapter 133 for supplying power to the interference signal acquisition unit according to the power supplied by the first power source.
Specifically, the power adapter is connected to a first power supply which provides an input power supply for the signal generation module, and converts the first power supply into an electrical signal required by the interference test module to supply power to the interference test module. Wherein the power adapter may comprise a self-energizing series power adapter.
In this embodiment, the interference testing module further includes: a power adapter; the input end of the power adapter is connected with a first power supply; the output end of the power adapter is connected with the interference signal acquisition unit; the power adapter supplies power to the interference signal acquisition unit according to the electric energy provided by the first power supply. The interference signal acquisition unit can be ensured to normally work, and a power supply signal is not required to be additionally provided for the interference signal acquisition unit.
The foregoing embodiment describes an interference testing module of a cable dielectric loss testing apparatus, and when a dielectric loss test is performed on a cable to be tested, a signal generating module is first required to convert an electrical signal provided by an accessed dc power supply into an electrical signal required by the test, where the signal generating module is further described with reference to an embodiment, and in an embodiment, as shown in fig. 7, the signal generating module 12 includes: a high voltage generator 121, a resistor divider 122 and a second resistor 123; a first output end of the high voltage generator 121 is connected to one end of the resistor divider 122 and one end of the second resistor 123, respectively; the second output end of the high voltage generator 121, the other end of the cable 15 to be tested and the other end of the resistive divider 122 are all grounded; the other end of the second resistor 123 is connected with one end of the cable 15 to be tested; the dielectric loss test module 14 is respectively connected with two ends of the resistive divider 122; the dielectric loss test module 14 is respectively connected with two ends of the second resistor 123;
a high voltage generator 121 for providing an input voltage to the cable to be tested;
and the dielectric loss test module 14 is configured to collect the voltage of the resistor voltage divider and the voltage of the second resistor, and determine a dielectric loss value of the cable to be tested according to the voltage of the resistor voltage divider, the voltage of the second resistor, and the interference electrical signal.
Specifically, the high voltage generator may receive an electrical signal provided by the dc power supply, and transmit the electrical signal to the cable to be tested after boosting or stepping down the electrical signal. In an example, when a dielectric loss test is performed on a cable to be tested, an electrical signal provided by a direct current power supply can be converted into an electrical signal which is 0.5 times, 1.0 times and 1.5 times of the rated voltage of the cable to be tested through a high voltage generator and transmitted to the cable to be tested. The electrical signal provided by the dc power source may include an electrical signal with a voltage of 220V. Optionally, the high voltage generator is a 0.1Hz ultra low frequency high voltage generator.
Because the voltage that carries out the dielectric loss test after the high voltage generator converts the voltage that DC power supply provided is experimental, is the high-voltage signal of tens of thousands of volts, consequently can not the direct measurement signal of telecommunication on the cable that awaits measuring, at this moment, can connect in parallel through resistance divider and cable that awaits measuring, realize the equivalence to the signal of telecommunication on the cable that awaits measuring, and then dielectric loss test module only need gather the voltage signal of resistance divider can. The equivalent of the current on the cable to be tested can be realized by connecting the second resistor in series with the cable to be tested, and then the dielectric loss test module only needs to collect the current signal on the second resistor, and can also collect the voltage signal on the second resistor. The dielectric loss test module can calculate the dielectric loss value of the cable to be tested according to the collected voltage signal on the resistance voltage divider, the collected current signal on the second resistor and the collected interference electric signal. If the voltage signal on the second resistor is collected, the current on the second resistor needs to be calculated according to the resistance R of the second resistor and the voltage U1 of the second resistor and according to the condition that I is U1/R, and then the dielectric loss test module can calculate the dielectric loss value of the cable to be tested according to the collected voltage signal on the resistor divider, the collected current signal on the second resistor and the collected interference electric signal.
In this embodiment, the signal generating module includes: the high-voltage generator, the resistor divider and the second resistor; the first output end of the high-voltage generator is respectively connected with one end of the resistor voltage divider and one end of the second resistor; the second output end of the high-voltage generator, the other end of the cable to be tested and the other end of the resistance voltage divider are all grounded; the other end of the second resistor is connected with one end of the cable to be tested; the dielectric loss testing module is respectively connected with two ends of the resistance voltage divider; the dielectric loss testing module is respectively connected with two ends of the second resistor; the high-voltage generator provides input voltage for the cable to be tested; the dielectric loss test module collects the voltage of the resistance voltage divider and the voltage of the second resistor respectively, determines the dielectric loss value of the cable to be tested according to the voltage of the resistance voltage divider, the voltage of the second resistor and the interference electric signal, can provide test voltage for the cable to be tested, realizes the equivalence of the voltage and the current on the cable to be tested when the cable to be tested receives high-voltage test voltage, and further realizes the acquisition of the voltage and the current on the cable to be tested so as to calculate the dielectric loss value.
The above embodiments describe the signal generating module including the resistor divider, and the resistor divider is further described with an embodiment, as shown in fig. 8, the resistor divider 122 includes: a third resistor 1221 and a fourth resistor 1222; one end of the third resistor 1221 is connected to the first output end of the high voltage generator 121 and one end of the second resistor 123, respectively; the other end of the third resistor 1221 is connected to one end of the fourth resistor 1222; the other end of the fourth resistor 1222 is grounded; the dielectric loss test module 14 is connected with two ends of the third resistor 1221;
and the dielectric loss testing module 14 is used for acquiring the voltage on the third resistor as the voltage of the resistor voltage divider.
Specifically, the resistor divider includes two resistors, namely a third resistor and a fourth resistor, where the resistance of the fourth resistor is greater than the resistance of the third resistor, and the difference between the resistance of the fourth resistor and the resistance of the third resistor is greater than a preset resistance threshold. The resistance value of the fourth resistor needs to be far larger than that of the third resistor, the resistance value of the fourth resistor is very large, namely the resistance value of the third resistor is negligible in a resistor divider formed by the fourth resistor and the third resistor which are connected in series, namely, the voltage on the fourth resistor can be equivalent to the voltage on the cable to be tested and is the voltage of tens of thousands of volts. At this time, the dielectric loss test module only needs to acquire the voltage on the third resistor, and then the voltage on the fourth resistor, namely the voltage on the cable to be tested, can be calculated according to the resistance relation between the third resistor and the fourth resistor.
In the present embodiment, since the resistor divider includes: a third resistor and a fourth resistor; one end of the third resistor is respectively connected with the first output end of the high-voltage generator and one end of the second resistor; the other end of the third resistor is connected with one end of the fourth resistor; the other end of the fourth resistor is grounded; the dielectric loss testing module is connected with two ends of the third resistor; and the dielectric loss testing module acquires the voltage on the third resistor as the voltage of the resistor divider. The voltage on the cable to be tested can be equivalent through the resistor divider, and then the voltage of the large resistor, namely the voltage on the cable to be tested, can be determined through collecting the voltage on the small resistor and the relation of the proportional resistance, so that data are provided for the subsequent calculation of the dielectric loss value of the cable to be tested.
The foregoing embodiment describes a cable dielectric loss testing apparatus, and when a dielectric loss experiment is performed, a dielectric loss testing module is required to calculate an acquired electrical signal, and when the dielectric loss testing module works, a power supply is required to supply power to the dielectric loss testing module, and now an embodiment describes a power supply for supplying power, in an embodiment, as shown in fig. 9, the cable dielectric loss testing apparatus further includes: a second power supply 16;
and the second power supply 16 is used for supplying power to the dielectric loss testing module 14.
Alternatively, the second power source may be a battery; or may be a power interface, through which an external power source is connected, without limitation.
In this embodiment, the cable dielectric loss testing apparatus further includes: a second power supply; the second power supply supplies power to the dielectric loss test module to ensure the dielectric loss test module to work normally.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A cable dielectric loss testing apparatus, the apparatus comprising: the device comprises a shielding assembly, a signal generation module, an interference test module and a dielectric loss test module;
the signal generating module is used for providing a test signal for the cable to be tested;
the shielding assembly is arranged on the cable to be tested and used for outputting an interference electric signal on a protective layer of the cable to be tested;
the interference test module is used for collecting an interference electric signal output by the shielding component and transmitting the interference electric signal to the dielectric loss test module;
the dielectric loss test module is used for collecting the test signal output by the signal generation module and determining the dielectric loss value of the cable to be tested according to the test signal and the interference electric signal.
2. The device of claim 1, wherein the shielding assembly comprises a shielding ring and a first resistor, the shielding ring is mounted on the cable to be tested, one end of the first resistor is connected with the shielding ring, and the other end of the first resistor is grounded;
the interference test module is used for collecting the electric signal on the first resistor as the interference electric signal.
3. The apparatus of claim 2, wherein the jammer electrical signal is a high side electrical signal, the jammer test module comprising: an interference signal acquisition unit and an isolation unit; wherein the content of the first and second substances,
the interference signal acquisition unit is used for acquiring a low-voltage side electric signal on the first resistor and transmitting the low-voltage side electric signal on the first resistor to the isolation unit;
the isolation unit is used for converting low-voltage side electric signals on the first resistor into high-voltage side electric signals and transmitting the converted high-voltage side electric signals to the dielectric loss testing module.
4. The apparatus of claim 3, wherein the isolation unit comprises: the device comprises a signal modulation circuit, an electro-optical conversion circuit, an optical fiber, a photoelectric conversion circuit and a signal demodulation circuit;
the signal modulation circuit is used for modulating the low-voltage side electric signal on the first resistor into an electric signal which can be transmitted by an optical fiber;
the electro-optical conversion circuit is used for converting the electric signal which can be transmitted by the optical fiber into an optical signal and transmitting the optical signal to the photoelectric conversion circuit through the optical fiber;
the photoelectric conversion circuit is used for converting the optical signal into a high-voltage side electric signal;
and the signal demodulation circuit is used for demodulating the high-voltage side electric signal and transmitting the demodulated high-voltage side electric signal to the dielectric loss test module.
5. The apparatus of claim 3, wherein the interference testing module further comprises: a power adapter; the input end of the power adapter is connected with a first power supply; the output end of the power adapter is connected with the interference signal acquisition unit;
the power adapter is used for supplying power to the interference signal acquisition unit according to the electric energy provided by the first power supply.
6. The apparatus of claim 1, wherein the signal generation module comprises: the high-voltage generator, the resistor divider and the second resistor; the first output end of the high-voltage generator is respectively connected with one end of the resistor voltage divider and one end of the second resistor; the second output end of the high-voltage generator, the other end of the cable to be tested and the other end of the resistance voltage divider are all grounded; the other end of the second resistor is connected with one end of the cable to be tested; the dielectric loss testing module is respectively connected with two ends of the resistance voltage divider; the dielectric loss testing module is respectively connected with two ends of the second resistor;
the high-voltage generator is used for providing input voltage for the cable to be tested;
the dielectric loss testing module is used for respectively collecting the voltage of the resistance voltage divider and the voltage of the second resistor, and determining the dielectric loss value of the cable to be tested according to the voltage of the resistance voltage divider, the voltage of the second resistor and the interference electric signal.
7. The apparatus of claim 6, wherein the resistor divider comprises: a third resistor and a fourth resistor; one end of the third resistor is connected with the first output end of the high-voltage generator and one end of the second resistor respectively; the other end of the third resistor is connected with one end of the fourth resistor; the other end of the fourth resistor is grounded; the dielectric loss testing module is connected with two ends of the third resistor;
and the dielectric loss testing module is used for collecting the voltage on the third resistor as the voltage of the resistor voltage divider.
8. The apparatus of claim 7, wherein a resistance of the fourth resistor is greater than a resistance of the third resistor, and a difference between the resistance of the fourth resistor and the third resistor is greater than a predetermined threshold.
9. The apparatus of claim 1, further comprising: a second power supply;
and the second power supply is used for supplying power to the dielectric loss test module.
10. The apparatus of claim 6, wherein the high voltage generator is a 0.1Hz ultra low frequency high voltage generator.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101609108A (en) * | 2008-06-19 | 2009-12-23 | 徐启峰 | The measuring method of voltage or current signal and realize the sensor of this method |
| CN204241572U (en) * | 2014-11-19 | 2015-04-01 | 国网四川省电力公司电力科学研究院 | High-precision electric cable dielectric loss measurement test sampling apparatus |
| CN105116287A (en) * | 2015-08-24 | 2015-12-02 | 江苏省电力公司南京供电公司 | High-voltage cable line fault on-line positioning system and positioning method thereof |
| CN204882748U (en) * | 2015-07-22 | 2015-12-16 | 国网河南省电力公司检修公司 | Arrester on -line monitoring system |
| CN108710048A (en) * | 2018-07-26 | 2018-10-26 | 云南电网有限责任公司曲靖供电局 | The lightning arrester monitoring device and system warned with acousto-optic |
| CN209590133U (en) * | 2018-12-25 | 2019-11-05 | 东莞市精微创达仪器有限公司 | A kind of resistance meter based on batch testing |
| CN210199207U (en) * | 2019-06-19 | 2020-03-27 | 上海大帆电气设备有限公司 | Ultralow frequency dielectric loss test system |
| CN111220855A (en) * | 2020-01-22 | 2020-06-02 | 西北核技术研究院 | Method for measuring conducted interference signal in strong electromagnetic environment |
-
2021
- 2021-04-23 CN CN202110439360.1A patent/CN113252990B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101609108A (en) * | 2008-06-19 | 2009-12-23 | 徐启峰 | The measuring method of voltage or current signal and realize the sensor of this method |
| CN204241572U (en) * | 2014-11-19 | 2015-04-01 | 国网四川省电力公司电力科学研究院 | High-precision electric cable dielectric loss measurement test sampling apparatus |
| CN204882748U (en) * | 2015-07-22 | 2015-12-16 | 国网河南省电力公司检修公司 | Arrester on -line monitoring system |
| CN105116287A (en) * | 2015-08-24 | 2015-12-02 | 江苏省电力公司南京供电公司 | High-voltage cable line fault on-line positioning system and positioning method thereof |
| CN108710048A (en) * | 2018-07-26 | 2018-10-26 | 云南电网有限责任公司曲靖供电局 | The lightning arrester monitoring device and system warned with acousto-optic |
| CN209590133U (en) * | 2018-12-25 | 2019-11-05 | 东莞市精微创达仪器有限公司 | A kind of resistance meter based on batch testing |
| CN210199207U (en) * | 2019-06-19 | 2020-03-27 | 上海大帆电气设备有限公司 | Ultralow frequency dielectric loss test system |
| CN111220855A (en) * | 2020-01-22 | 2020-06-02 | 西北核技术研究院 | Method for measuring conducted interference signal in strong electromagnetic environment |
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