Apparatus and method for detecting SO2 in SF6 electrical equipment based on ultraviolet fluorescence

Abstract

The invention provides an apparatus and method for detecting SO2 in SF6 electrical equipment based on ultraviolet fluorescence. The apparatus comprises an induction regulator, a corona-free experimental transformer, a partial discharge protection-free resistor, a standard capacitance voltage divider, a non-inductive resistor, a GIS analog element and a digital storage oscilloscope. An ultraviolet fluorescence system is arranged and comprises a fluorescence excitation assembly, a fluorescence capturing assembly and a gas passage assembly. In detection, performance parameters of the system are measured at first, and then the concentration of a discharging trace component of sulfur hexafluoride gas is detected. The apparatus and method provided by the invention can realize real-time, on-line and continuous monitoring and are widely applicable to detection of decomposition components of sulfur hexafluoride under the condition of partial discharging in SFT gas insulation electrical equipment, especially GIS equipment; and a simple and reliable method is provided for theoretical analysis of and applied research on state detection of SF6 in GIS equipment in scientific research, teaching and research institutes, equipment manufacturers and electrical power systems.

Description

technical field [0001] The invention belongs to the technical field of on-line monitoring of the insulation state of gas-insulated electrical equipment, and in particular relates to a method for detecting SF based on ultraviolet fluorescence technology. 6 SO in electrical equipment 2 devices and methods. Background technique [0002] Gas-insulated combined electrical appliances (GIS for short) have the advantages of small footprint, safe and reliable operation, less maintenance workload, long maintenance cycle, etc., and have been widely used in power systems. However, the inevitable insulation defects inside GIS will gradually expand and cause faults to occur. The most common electrical fault feature is partial discharge (PD) before complete insulation breakdown or flashover. Studies have shown that PD can cause insulating gas SF 6 Decomposition occurs, and with the O in the impurity 2 、H 2 O and organic matter undergo complex chemical reactions to generate SOF 2 , SO...

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Problems solved by technology

[0005] (1) Infrared spectrum detection is to detect the gas concentration by comparing the intensity change of the incident infrared light and the outgoing infrared light after being absorbed by the gas. Since the SF under PD 6 The concentration of the decomposed components is small, generally on the order of 0.01μL / L-10μL / L, so the light intensity of the incident infrared light and the outgoing infrared light after the absorption of the decomposed gas is small, plus the current detection of infrared light intensity The infrared detector used has low sensitivity, which leads to low detection sensitivity of infrared spectroscopy. Even if the long gas cell described in this published patent is used, the sensitivity is only at the μL / L level

[0006] (2) Due to the low detection sensitivity of infrared spectroscopy, to achieve a certain detection sensitivity, it is necessary to choose SF under PD 6 The stronger absorption peak of the decomposed component is used as the characteristic absorption peak, due to the SF under PD 6 The decomposition components are more complicated, and the infrared absorption peaks of each component overlap, which will cause cross interference during detection, resulting in a greatly reduced detection accuracy of infrared spectroscopy

[0007] (3) The gas cell used in this patent is a long optical path gas cell, which is a cylinder with a shape of Φ104mm*500mm. The gas cell has a large volume (about 4.25L), and each measurement requires a large amount of sample gas, which increases the measurement cost and difficulty

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