CN209841998U - System for detecting discharge information in GIS - Google Patents

Abstract

The utility model discloses a system for detecting discharge information inside a GIS, which belongs to the technical field of power transmission and transformation equipment. The utility model system includes: solar-blind single-photon detector, UHF sensor, high-frequency current sensor, acquisition card and processing equipment, and the processing equipment is used to collect voltage signal, UHF signal or pulse current by comparing the acquisition channel To determine whether the GIS is internally discharged, when determining the internal discharge of the GIS, the internal discharge information of the GIS is detected according to the voltage signal, UHF signal or pulse current collected by the acquisition channel. The utility model improves GIS internal discharge measurement sensitivity, anti-interference performance, diagnostic accuracy and reliability of diagnostic results, and can realize single-photon detection and diagnosis of GIS internal discharge. Identification, discharge measurement, and other functions.

Description

A System for Detecting Discharge Information in GIS

technical field

The utility model relates to the technical field of power transmission and transformation equipment, and more particularly relates to a system for detecting discharge information inside a GIS.

Background technique

With the widespread application of gas-insulated combined electrical appliances (GIS), the operational reliability of GIS equipment has gradually attracted the attention of the international community and the power sector. According to nearly 40 years of operating experience, insulation failure has always been one of the important factors affecting the reliability of GIS. Partial discharge is the main manifestation that leads to the deterioration of GIS equipment insulation and the occurrence of flashover faults. Typical discharge defects inside GIS are mainly divided into two types: discharge defects in SF6 gas and discharge defects in solid insulation (basin insulators, supporting insulators) according to the location where the discharge occurs. Among them, discharge defects in SF6 gas can be divided into two types: It is the tip discharge on the high-voltage conductor (bus bar), the tip discharge on the low-voltage side (GIS shell), the floating potential discharge on the high-voltage side, the floating potential discharge on the low-voltage side, the floating discharge of the poor contact type, etc.; the discharge defects on the insulator can be divided into Dirt on the surface of the insulator, metal particles, and internal cracks or air gaps in the insulator; considering the location of the discharge, the discharge defect on the insulator is likely to induce flashover faults along the surface, and its hazards are greater than that of the discharge in SF6 gas.

Inside the GIS equipment, the duration of the partial discharge pulse is very short, and the rise time of the wave head is only about 1ns. This kind of steep pulse with an extremely short duration contains partial discharge electromagnetic wave signals up to GHz, and the partial discharge will be generated in the GIS equipment. A flowing electromagnetic wave is generated on the shell, and a high-frequency discharge pulse current flows on the grounding line, and the shell presents a high-frequency voltage to the ground and generates electromagnetic waves to the surrounding space. Partial discharge will also cause a sudden increase in the pressure of the channel gas, generating ultrasonic waves in the gas of the GIS equipment, which will reflect and transmit when transmitted to the metal casing, and various sound waves, such as longitudinal waves, transverse waves and surface waves, will appear on the metal casing. Partial discharges in GIS equipment also generate light and decompose SF6 gas. These physical and chemical effect changes accompanying partial discharge are the basis for realizing the online detection of GIS equipment. At present, the methods widely used in the field are UHF method, ultrasonic method and SF6 gas decomposition product analysis.

The detection sensitivity of the ultrasonic method is low, and it is not sensitive enough for the detection of some types of insulation internal discharge defects, but it is better for the detection of free metal particle faults. At the same time, this method is relatively difficult to judge the type of discharge fault, and cannot achieve the calibration of the apparent discharge capacity. The ultra-high frequency (UHF) method has high sensitivity, but it is difficult to use the UHF signal amplitude to characterize the severity of partial discharge, and it is difficult to achieve the calibration of the apparent discharge volume. For the analysis of gas decomposition products, since the type of partial discharge insulation defect and the development process of the discharge have not yet established a clear correlation with the decomposition components of SF6 gas, mature guidelines and judgment standards have not yet been formed like transformer oil chromatographic analysis. A lot of research work still needs to be carried out from the accumulation of laboratory simulation defect faults and field fault cases, which leads to the inability of this method to accurately determine the fault type and be applied to actual online monitoring.

In _SF6 gas, the spectrum of corona discharge radiation is mainly concentrated in the near-ultraviolet region, and there is a continuous spectrum peak in the near-ultraviolet region from 250nm to 400nm, which provides an important basis for the spectral range of photoelectric detection. At present, there are many optical methods for electric equipment discharge detection, which are mainly divided into optical imaging method and optical pulse method, and are realized by infrared imager, ultraviolet imager and other equipment. This type of method relies on expensive optical measurement and display equipment, and has disadvantages such as high cost, complicated operation, insufficient sensitivity, difficulty in predicting the danger of early discharge, and inability to quantitatively express the degree of discharge. Therefore, it is urgent to propose low-cost, high-sensitivity and effective A combined optoelectronic diagnostic system for detecting partial discharge in GIS.

Utility model content

The utility model proposes a system for detecting internal discharge information in GIS in order to realize partial discharge measurement and discharge type diagnosis in GIS, improve partial discharge measurement sensitivity, anti-interference performance, diagnostic accuracy, and diagnostic result reliability. include:

The solar-blind single-photon detector is used to detect whether the internal discharge of the GIS generates ultraviolet light signals. When the internal discharge of the GIS generates ultraviolet light signals, the solar-blind single-photon detector receives the ultraviolet light with a solar-blind band of 260nm to 280nm generated by the internal discharge of the GIS. Optical signal, the solar-blind ultraviolet light signal with a band of 260nm to 280nm is converted into a voltage signal by a solar-blind single-photon detector and transmitted to the acquisition card;

The UHF sensor is used to detect whether the internal discharge of the GIS generates a UHF signal. When the GIS internal discharge generates a UHF signal, the UHF sensor receives the UHF signal and transmits it to the acquisition card;

The high-frequency current sensor is used to detect whether the internal discharge of the GIS generates a pulse current. When the internal discharge of the GIS generates a pulse current, the high-frequency current sensor receives the pulse current generated by the internal discharge of the GIS and transmits it to the acquisition card;

The acquisition card has multiple acquisition channels, and each acquisition channel is set with a trigger level. When the amplitude of the voltage signal, UHF signal or pulse current received by any channel is greater than the trigger amplitude of the trigger level, the acquisition card guides Multi-channel synchronous acquisition of voltage signals, UHF signals and pulse currents through acquisition channels; and

The processing equipment is used to determine whether the internal discharge of the GIS is discharged by comparing whether the collection channel collects a voltage signal, a UHF signal or a pulse current. Current detection GIS internal discharge information.

Optionally, the discharge information includes: discharge type, discharge amount and corona area.

Optionally, the acquisition card can be set to perform synchronous acquisition of multiple acquisition channels after a specific channel is triggered.

Optionally, the specific channels include: a voltage signal trigger channel, a UHF signal trigger channel and a pulse current signal trigger channel.

Optionally, the processing device identifies the GIS discharge type by drawing the time-domain pulse sequence spectrum and phase spectrum of the voltage signal, UHF signal or pulse current collected by the acquisition channel and comparing it with the standard discharge spectrum.

Optionally, the processing device calculates the area of the discharge corona by counting the number of photons in the discharge period, and calculates the discharge amount in combination with the current pulse signal.

The utility model can realize the single-photon detection and diagnosis of the internal discharge of the GIS, and the detection band is the sun-blind ultraviolet band, which can realize the functions of discharge type identification, discharge measurement, and the like.

The utility model highly integrates a sun-blind single-photon detector, a UHF sensor, and a high-frequency current sensor. The three sensors can be directly connected with the acquisition card, and the synchronous acquisition of optical-electrical signals is realized through the acquisition card. Through the processing equipment to automatically judge the existence of discharge, it is possible to judge the optical path between the discharge source and the sensor, and the judgment of electrical barriers. Compared with only using a single sensor, the reliability and sensitivity of the detection are improved. The processing equipment automatically calculates the PRPD spectrum and time-domain pulse sequence spectrum of the optical-electrical signal pulse, and compares it with the standard discharge mode spectrum pre-calibrated by the system to obtain the most similar discharge type and realize the identification of the discharge type. Compared with the UHF detection method only, the recognition accuracy and sensitivity are improved. The processing equipment counts the pulses of the light pulse sequence, automatically calculates the corona area during discharge, and then combines the current pulse sequence to obtain the light-current pulse sequence, automatically calculates the discharge amount, and improves the sensitivity of the discharge amount calculation compared with the current pulse method only .

Description of drawings

Fig. 1 is a system structure diagram for detecting internal discharge information of GIS according to the utility model.

Detailed ways

Exemplary embodiments of the present invention are now described with reference to the accompanying drawings; however, the present invention may be implemented in many different forms and are not limited to the embodiments described herein, which are provided for exhaustive and complete The utility model is disclosed and fully conveys the scope of the utility model to those skilled in the art. The terms used in the exemplary embodiments shown in the drawings do not limit the present invention. In the figures, the same units/elements are given the same reference numerals.

Unless otherwise specified, the terms (including scientific and technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it can be understood that terms defined by commonly used dictionaries should be understood to have consistent meanings in the context of their related fields, and should not be understood as idealized or overly formal meanings.

The utility model proposes a system for detecting discharge information inside a GIS, as shown in Figure 1, including:

The solar-blind single-photon detector is used to detect whether the internal discharge of the GIS generates ultraviolet light signals. When the internal discharge of the GIS generates ultraviolet light signals, the solar-blind single-photon detector receives the ultraviolet light with a solar-blind band of 260nm to 280nm generated by the internal discharge of the GIS. Optical signal, the solar-blind ultraviolet light signal with a band of 260nm to 280nm is converted into a voltage signal by a solar-blind single-photon detector and transmitted to the acquisition card;

The UHF sensor is used to detect whether the internal discharge of the GIS generates a UHF signal. When the GIS internal discharge generates a UHF signal, the UHF sensor receives the UHF signal and transmits it to the acquisition card;

The high-frequency current sensor is used to detect whether the internal discharge of the GIS generates a pulse current. When the internal discharge of the GIS generates a pulse current, the high-frequency current sensor receives the pulse current generated by the internal discharge of the GIS and transmits it to the acquisition card;

The acquisition card has multiple acquisition channels, and each acquisition channel is set with a trigger level. When the amplitude of the voltage signal, UHF signal or pulse current received by any channel is greater than the trigger amplitude of the trigger level, the acquisition card guides Multi-channel synchronous acquisition of voltage signal, UHF signal and pulse current through the acquisition channel. The acquisition card can be set to trigger the specific channel to perform multi-channel synchronous acquisition. Specific channels include: voltage signal trigger channel, UHF signal trigger channel and pulse current signal trigger channel;

The processing equipment is used to determine whether the internal discharge of the GIS is discharged by comparing whether the collection channel collects a voltage signal, a UHF signal or a pulse current. Current detection GIS internal discharge information, discharge information includes: discharge type, discharge amount and corona area. The processing equipment draws the time-domain pulse sequence spectrum and phase spectrum of the voltage signal, UHF signal or pulse current collected by the acquisition channel, and compares it with the standard discharge spectrum to identify the GIS discharge type. The processing equipment calculates the area of the discharge corona by counting the number of photons in the discharge period, and calculates the discharge volume in combination with the current pulse signal.

The utility model can realize the single-photon detection and diagnosis of the internal discharge of the GIS, and the detection band is the sun-blind ultraviolet band, which can realize the functions of discharge type identification, discharge measurement, and the like.

The utility model highly integrates a sun-blind single-photon detector, a UHF sensor, and a high-frequency current sensor. The three sensors can be directly connected with the acquisition card, and the synchronous acquisition of optical-electrical signals is realized through the acquisition card. Through the processing equipment to automatically judge the existence of discharge, it is possible to judge the optical path between the discharge source and the sensor, and the judgment of electrical barriers. Compared with only using a single sensor, the reliability and sensitivity of the detection are improved. The processing equipment automatically calculates the PRPD spectrum and time-domain pulse sequence spectrum of the optical-electrical signal pulse, and compares it with the standard discharge mode spectrum pre-calibrated by the system to obtain the most similar discharge type and realize the identification of the discharge type. Compared with the UHF detection method only, the recognition accuracy and sensitivity are improved. The processing equipment counts the pulses of the light pulse sequence, automatically calculates the corona area during discharge, and then combines the current pulse sequence to obtain the light-current pulse sequence, automatically calculates the discharge amount, and improves the sensitivity of the discharge amount calculation compared with the current pulse method only .

Claims (6)

1. A system for detecting GIS internal discharge information, characterized in that the system comprises: The solar-blind single-photon detector is used to detect whether the internal discharge of the GIS generates ultraviolet light signals. When the internal discharge of the GIS generates ultraviolet light signals, the solar-blind single-photon detector receives the ultraviolet light with a solar-blind band of 260nm to 280nm generated by the internal discharge of the GIS. Optical signal, the solar-blind ultraviolet light signal with a band of 260nm to 280nm is converted into a voltage signal by a solar-blind single-photon detector and transmitted to the acquisition card; The UHF sensor is used to detect whether the internal discharge of the GIS generates a UHF signal. When the GIS internal discharge generates a UHF signal, the UHF sensor receives the UHF signal and transmits it to the acquisition card; The high-frequency current sensor is used to detect whether the internal discharge of the GIS generates a pulse current. When the internal discharge of the GIS generates a pulse current, the high-frequency current sensor receives the pulse current generated by the internal discharge of the GIS and transmits it to the acquisition card; The acquisition card has multiple acquisition channels, and each acquisition channel is set with a trigger level. When the amplitude of the voltage signal, UHF signal or pulse current received by any channel is greater than the trigger amplitude of the trigger level, the acquisition card guides Multi-channel synchronous acquisition of voltage signals, UHF signals and pulse currents through acquisition channels; and The processing equipment is used to determine whether the internal discharge of the GIS is discharged by comparing whether the collection channel collects a voltage signal, a UHF signal or a pulse current. Current detection GIS internal discharge information. 2. The system according to claim 1, wherein the discharge information includes: discharge type, discharge amount and corona area. 3. The system according to claim 1, wherein the acquisition card can be configured to perform synchronous acquisition of multiple acquisition channels after a specific channel is triggered. 4. The system according to claim 3, wherein the specific channels include: a voltage signal trigger channel, a UHF signal trigger channel and a pulse current signal trigger channel. 5. The system according to claim 1, characterized in that, the processing device draws the time-domain pulse sequence spectrum and phase spectrum of the voltage signal, ultra-high frequency signal or pulse current collected by the acquisition channel, and the standard discharge spectrum Compare and identify GIS discharge types. 6. The system according to claim 1, wherein the processing device calculates the area of the discharge corona by counting the number of photons in the discharge period, and calculates the discharge amount in combination with the current pulse signal.