CN212514849U - Transformer partial discharge monitoring and positioning system adopting multiple composite sensors - Google Patents

Abstract

The utility model relates to an adopt many composite sensor's transformer partial discharge monitoring positioning system, including piezoelectric type AE sensor and UHF electromagnetic wave sensor integrated composite sensor, multichannel pilot frequency data synchronization acquisition device, transmission network, data server, application server and user terminal, composite sensor pass through multichannel pilot frequency data synchronization acquisition device and be connected with transmission network, transmission network be connected with data server, application server and user terminal respectively. Compared with the prior art, the utility model provides a only rely on single nature signal source to judge at present whether the PD signal comes from inside the transformer.

Description

Transformer partial discharge monitoring and positioning system adopting multiple composite sensors

Technical Field

The utility model relates to a transformer partial discharge monitoring positioning system especially relates to an adopt many composite sensor's transformer partial discharge monitoring positioning system.

Background

When Partial Discharge (PD) occurs in the presence of defects in the transformer oil paper insulation, electric pulses, electromagnetic radiation, ultrasonic waves, light and some new products are generated, and physical and chemical reactions such as local overheating are caused. Therefore, in principle, these phenomena, if detectable, can be used as indications of PD defects. Methods for locating transformers under applied voltage have been developed including electrical, ultrasonic (AE), electromagnetic Ultra High Frequency (UHF), optical and thermal locating. This is also a positioning method if the PD is subjected to external stimuli, such as X-or gamma-ray irradiation, in addition to the applied voltage.

Ultrasonic (AE) positioning measures the time delay of signals measured by different sensors through a plurality of AE sensors, sets up an equation set according to the position of the AE sensor, equivalent sound velocity and time delay, and then solves a nonlinear equation set, so that the position of a PD source can be determined. According to the difference of the reference signals, the AE detection positioning can be divided into an electro-acoustic detection positioning method and an acoustic-acoustic detection positioning method, wherein the electro-acoustic detection positioning method uses the electric pulse of the PD as a trigger reference signal, and the acoustic-acoustic detection positioning method selects one AE sensor as a reference probe to measure the relative time difference of the same PD ultrasonic signal when the same PD ultrasonic signal is transmitted to other sensors. The ultrahigh frequency (UHF) method positioning is PD positioning using UHF electromagnetic wave signals, and is based on the fmax shortest optical path principle followed by electromagnetic wave diffraction, i.e., electromagnetic wave propagates along a ray, and it is considered that signals received by a UHF sensor are wave front reflection of a wavelet that the PD signals first arrive along the shortest optical path and with the minimum propagation time. The UHF positioning method and the AE positioning method are based on the principle of signal arrival time difference, namely, signal time delay is estimated, a time delay equation set is arranged in parallel, and then the space position of a PD source is solved.

At present, there are many researches and application reports on a UHF and AE combined transformer PD monitoring and positioning method, in which a sensor for respectively detecting UHF and AE signals generated by a PD is used, and a PD electromagnetic wave signal detected by the UHF sensor is used as a time reference, so as to obtain a time delay of the received AE signal, and further calculate a distance between a discharge point and the sensor, as shown in fig. 1. The system and the method are based on UHF and AE sensors which work independently, generally 1 UHF sensor and 3-4 external AE sensors are added, signal acquisition is carried out simultaneously, 3-4 time delays are calculated by taking an electromagnetic wave signal as a reference, an equation set is listed according to the position, the equivalent sound velocity and the time delay of the AE sensor, and a nonlinear equation set is solved, so that the position of a PD source is determined. The monitoring system and the method thereof use an external AE sensor: when the transformer works under the actual operation condition, the problems of external signal interference of a transformer substation, AE signal attenuation caused by a shell of transformer equipment, transmission multipath caused by AE signals in different medium acoustic impedances of transformer equipment materials (insulating oil, steel plates and the like) and the like exist, and the defects of poor system anti-interference performance, incapability of working under the weak discharge condition, large deviation of PD source positioning and the actual position and the like exist as shown in FIG. 2.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a transformer partial discharge monitoring positioning system who adopts many compound sensor in order to overcome the defect that above-mentioned prior art exists.

The purpose of the utility model can be realized through the following technical scheme:

a transformer partial discharge monitoring and positioning system adopting a multi-composite sensor comprises a composite sensor integrated by a piezoelectric AE sensor and a UHF electromagnetic wave sensor, a multi-channel pilot frequency data synchronous acquisition device, a transmission network, a data server, an application server and a user terminal, wherein the composite sensor is connected with the transmission network through the multi-channel pilot frequency data synchronous acquisition device, and the transmission network is respectively connected with the data server, the application server and the user terminal.

Preferably, the composite sensor is connected with the multi-channel pilot frequency data synchronous acquisition device through two coaxial cables.

Preferably, the composite sensor is arranged on the transformer shell in a preset built-in mode and an oil drain valve invasion built-in mode.

Preferably, the multichannel pilot frequency data synchronous acquisition device is stored in an outdoor terminal box and is provided with a channel for collecting 4 paths of electromagnetic waves UHF and 4 paths of ultrasonic waves AE of 4 composite sensors to total 8 paths of signals.

Preferably, the transmission network is an optical fiber ethernet network, and the optical fiber ethernet network forms a local area network with the multi-channel pilot frequency data synchronous acquisition device, the data server, the application server and the user terminal.

Preferably, the data server is provided with a storage array for storing 8 paths of original data of signals, which are obtained by the multi-channel pilot frequency data synchronous acquisition device and are counted by 4 paths of electromagnetic waves UHF and 4 paths of ultrasonic waves AE of 4 composite sensors.

Preferably, the user terminal is a server, a PC or a mobile notebook computer capable of deploying Web page software.

Preferably, the system further comprises a terminal cabinet for collecting load current and operating voltage signals of the transformer, and the terminal cabinet is connected with the transmission network.

Compared with the prior art, the utility model has the advantages of it is following:

1. the utility model discloses a can export the combined sensor of superfrequency UHF and ultrasonic wave AE signal simultaneously, has set up transformer PD monitoring and positioning system, and the effective data signal of synchronous monitoring superfrequency UHF and ultrasonic wave AE output can be witnessed together with each other, has solved and has only relied on single nature signal source to judge at present whether the PD signal comes from inside the transformer.

2. The built-in composite sensor based on ultrasonic AE detection avoids the problems of external signal interference of a transformer substation, AE signal attenuation caused by a transformer equipment shell, transmission multipath caused by AE signals in different medium acoustic impedances of transformer equipment materials (insulating oil, steel plates and the like) and the like when the transformer works under the actual operation working condition, and solves the defects that the existing monitoring system is poor in anti-interference performance, cannot work under the weak discharge working condition, and is large in PD source positioning and actual position deviation.

Drawings

FIG. 1 is a schematic diagram of a PD detection system and a positioning technology of a transformer based on combination of ultrahigh frequency and ultrasonic waves in the prior art;

FIG. 2 is a schematic diagram of external and internal ultrasonic AE sensors for monitoring PD of a transformer;

FIG. 3 is a block diagram of the partial discharge monitoring and positioning system of the transformer based on multiple composite sensors according to the present invention;

fig. 4 is a schematic diagram of the composite sensor module of the present invention;

FIG. 5 shows three mounting forms of the compound sensor of the present invention on the transformer housing;

fig. 6 is a data flow diagram of the system of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.

As shown in figure 3, the transformer partial discharge monitoring and positioning system adopting the multi-composite sensor comprises a composite sensor formed by integrally integrating a piezoelectric AE sensor and a UHF electromagnetic wave sensor, a multi-channel pilot frequency data synchronous acquisition device 4, other terminal cabinets 5, a transmission network 6, a data server 7, an application server 8 and a user terminal 9, wherein the composite sensor is installed on a shell of a transformer 1 and is connected with the transmission network 6 through the multi-channel pilot frequency data synchronous acquisition device 4, the transmission network 6 is respectively connected with the other terminal cabinets 5, the data server 7, the application server 8 and the user terminal 9, and the composite sensor comprises a preset built-in composite sensor 2 and an oil drain valve invasion built-in composite sensor 3.

The composite sensor comprises: the piezoelectric AE sensor and the UHF electromagnetic wave sensor are integrally designed, mutually independent AE and UHF signals are output through two coaxial cables, a signal output schematic diagram of a composite sensor module and a PD (potential of Hydrogen) test in transformer oil is shown in figure 4, and the signal output has the remarkable characteristic that the AE lags the time delay of a UHF signal delta t; two built-in installation forms of the composite sensor on the transformer shell are shown in fig. 5 and are a preset built-in form and a drain valve invasion built-in form, namely the composite sensor is directly contacted with the transformer insulating oil, wherein an AE sensor receives direct ultrasonic signals of PD ultrasonic waves, A is the drain valve invasion built-in form, and B is the preset built-in form.

The outdoor terminal box: the multi-channel pilot frequency data synchronous acquisition device is stored, 4 paths of electromagnetic waves UHF and 4 paths of ultrasonic waves AE of 4 composite sensors are collected to count 8 paths of signals, and the acquired data are transmitted to the data server through the optical fiber Ethernet.

The optical fiber Ethernet network comprises: a data flow diagram in the system is shown in fig. 6, wherein the system is formed by combining a multichannel pilot frequency data synchronous acquisition device, other terminal cabinet signals (mainly load current and running voltage signals of a transformer), a data server, an application server and a user (Web) terminal in an outdoor terminal box into a local area network by using optical fibers.

The data server: and 4 paths of electromagnetic waves UHF and 4 paths of ultrasonic waves AE of 4 composite sensors acquired by the multi-channel pilot frequency data synchronous acquisition device are stored, and the total amount of the original data is 8 paths of signals.

The application server: and accessing the latest monitoring data in the database server in real time to perform positioning solution, and returning solution result data to the data server.

The user (Web) terminal: based on a developed Web page, checking real-time (historical) monitoring data and a positioning solving result thereof in a data server, and setting working parameters of a multi-channel pilot frequency data synchronous acquisition device; the terminal can be a server, a PC or a mobile notebook computer which can deploy Web page software.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope of the present invention, and these modifications or replacements should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (8)

1. A transformer partial discharge monitoring and positioning system adopting a multi-composite sensor is characterized by comprising a composite sensor, a multi-channel pilot frequency data synchronous acquisition device, a transmission network, a data server, an application server and a user terminal, wherein the composite sensor is formed by integrally integrating a piezoelectric AE sensor and a UHF electromagnetic wave sensor, the composite sensor is connected with the transmission network through the multi-channel pilot frequency data synchronous acquisition device, and the transmission network is respectively connected with the data server, the application server and the user terminal.

2. The partial discharge monitoring and positioning system for the transformer using the multiple combined sensors as claimed in claim 1, wherein the combined sensors are connected with the multi-channel pilot frequency data synchronous acquisition device through two coaxial cables.

3. The partial discharge monitoring and positioning system for the transformer using the multiple composite sensors as claimed in claim 1, wherein the composite sensors are installed on the transformer housing through two types of preset built-in type and oil drain valve intrusion built-in type.

4. The partial discharge monitoring and positioning system of transformer using multiple composite sensors as claimed in claim 1, wherein said multi-channel synchronous acquisition device for different frequency data is stored in an outdoor terminal box, and a channel for collecting 4 electromagnetic waves UHF and 4 ultrasonic waves AE of 4 composite sensors for 8 signals in total is provided.

5. The partial discharge monitoring and positioning system of transformer using multiple composite sensors as claimed in claim 1, wherein the transmission network is an optical fiber ethernet network, and the optical fiber ethernet network forms a local area network with the multi-channel pilot frequency data synchronous acquisition device, the data server, the application server and the user terminal.

6. The partial discharge monitoring and positioning system for the transformer using the multiple composite sensors as claimed in claim 1, wherein the data server is provided with a storage array for storing 8 paths of original data of signals, which are obtained by the multi-channel pilot frequency data synchronous acquisition device, of 4 paths of electromagnetic waves UHF and 4 paths of ultrasonic waves AE of 4 composite sensors.

7. The transformer partial discharge monitoring and positioning system adopting multiple composite sensors as claimed in claim 1, wherein the user terminal is a server, a PC or a mobile notebook computer capable of deploying Web page software.

8. The transformer partial discharge monitoring and positioning system adopting the multiple composite sensors as claimed in claim 1, further comprising a terminal cabinet for collecting load current and operation voltage signals of the transformer, wherein the terminal cabinet is connected with the transmission network.

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