A discharge monitoring method based on organic semiconductor thin film

Abstract

A discharge monitoring method based on organic semiconductor thin films includes a polymer PFO film, a dual fiber optic probe, and a spectrometer. The end face of one of the dual fiber optic probes is covered with the polymer PFO film. When a discharge occurs in the monitoring area, both fiber optic probes receive signals simultaneously. The presence of the discharge is determined based on the spectra measured by the two probes.

Description

Technical Field

[0001] The invention relates to the technical field of partial discharge monitoring, and is a dual-fiber detection method based on organic semiconductor (PFO). Background Art

[0002] Corona discharge is a phenomenon that occurs in the early stages of partial discharge during high-voltage power transmission. Initially, the energy generated is low and difficult to detect. However, as the discharge energy increases, localized breakdown can damage the insulation in the line, often leading to significant power losses and power failures. Therefore, monitoring the early stages of partial discharge, promptly identifying the fault type, and formulating a reasonable maintenance plan are crucial for the safe and stable operation of power systems. Current methods for monitoring corona discharge include infrared imaging, ultraviolet imaging, magnetoresistive sensing, and ultrasonic monitoring. These methods generally suffer from shortcomings such as narrow sensor bandwidth and low sensitivity, resulting in low reliability in monitoring the early stages of partial discharge.

[0003] In order to solve the above problems, the present invention proposes a discharge monitoring method for an organic semiconductor thin film. Summary of the Invention

[0004] The present invention proposes a discharge monitoring method based on an organic semiconductor film. The monitoring system includes: a polymer PFO ([9,9-dioctylfluorenyl-2,7-diyl]end capped with DMP) film, a dual-fiber probe, and a spectrometer. In general photoelectric detection methods, the wavelength range of the optical signal of corona discharge is 280-400nm, while the wavelength range of sunlight and its diffuse reflection is 280-780nm. The sunlight signal will affect the detected optical signal. In addition, multiple corona discharges in discharge-prone areas will cause the monitoring signals to overlap. Taking the above problems into consideration, the present method is based on the absorption characteristics of the PFO film, absorbs the corona discharge signal between 200-400nm, and eliminates the influence of sunlight and other corona signals. The monitoring method proposed in this article is an "AND gate" signal system with the advantages of high accuracy, strong real-time performance, and simple operation.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is a thin-film organic semiconductor monitoring method bonded to an optical fiber probe, which realizes the accurate monitoring of partial discharge.

[0006] The polymer PFO film of the present invention is prepared as follows:

[0007] S1: Poly(vinyl alcohol) (PVA) was dissolved in water at a water bath temperature of 80-100 degrees Celsius to a concentration of 60 mg / ml, labeled as solution A.

[0008] S2: Spin-coating the PVA solution A on the glass substrate at a spin-coating speed of 1000-2000 rpm for 15-30 s to obtain an organic semiconductor film with uniform thickness of 500-1000 nm;

[0009] S3: dissolve polymer PFO in chloroform at room temperature to a concentration of 12.5 mg / ml, labeled as solution B;

[0010] S4: spin-coating the organic semiconductor solution B on the substrate after step S2, with a spin-coating speed of 1000-2000 rpm and a spin-coating time of 15-30 s to obtain an organic semiconductor film with uniform thickness of 150-200 nm;

[0011] S5 uses deionized water to soak the substrate with the organic semiconductor film, so that the lower PVA film dissolves in the water and the organic semiconductor PFO film automatically peels off the substrate;

[0012] S6: physically drying the PFO film obtained in S5 at room temperature and then laminating it on the optical fiber probe;

[0013] The present invention provides a partial discharge monitoring method based on a polymer optical fiber probe, which is used to monitor partial discharge signals. The untreated optical fiber probe and the optical fiber probe with a polymer film are placed in a discharge-prone area such as a tension clamp. When a discharge occurs in the detection area, both probe 1 and probe 2 receive signal input at the same time. Figure 5 The spectrum shown in FIG. 1 shows that discharge has occurred. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a flow chart for preparing the PFO polymer film of the present invention;

[0015] (1) PVA polymer solution is spin-coated on the glass surface;

[0016] (2) Generate a PVA film with a thickness of about 500 nm;

[0017] (3) Spin-coating a PFO film with a thickness of approximately 200 nm;

[0018] (4) After dissolving the PVA in deionized water, peel off the PFO film;

[0019] (5) Fiber optic probe without PFO film;

[0020] (6) Fiber optic probe with PFO film attached.

[0021] Figure 2 This is a physical picture of the PFO polymer film of the present invention;

[0022] Figure 3Schematic diagram of the structure of the optical fiber dual probe with PFO polymer film attached in the present invention, wherein probe 1 is a general optical fiber probe and probe 2 is an optical fiber probe with PFO film attached;

[0023] Figure 4 It is a structural diagram of the monitoring system of the present invention;

[0024] Figure 5 This is a spectrum diagram when a partial discharge signal is monitored in the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] The preparation method of polymer film is as follows ( Figure 1 ):

[0027] S1: Polymer PVA (polyvinyl alcohol) is dissolved in water at 80-100 degrees Celsius and ultrasonically vibrated to prepare a uniform solution A with a concentration of 60 mg / ml;

[0028] S2: PVA solution A was dropped onto a 15 mm × 15 mm × 1 mm glass surface at a spin coating speed of 1500 rpm for 30 s.

[0029] S3: dissolving polymer PFO in chloroform (CHCl3) at 60 degrees Celsius to a concentration of 12.5 mg / ml solution B;

[0030] S4: spin-coating the organic semiconductor solution B on the substrate after step S2 at a spin-coating speed of 1000 rpm and a spin-coating time of 30 s to obtain a second layer of organic semiconductor thin film with uniform thickness of 200 nm;

[0031] S5: soaking the sample obtained in step S4 with deionized water, so that the lower PVA film dissolves in the water, and the organic semiconductor PFO film automatically peels off the substrate and floats on the surface of the deionized water;

[0032] In step S6, a hole with a radius of 5 mm is punched on a 15 mm × 15 mm × 0.2 mm PET (polyethylene terephthalate) sheet using a hole puncher. The PFO film floating in step S5 is fished out with the PET sheet and dried at room temperature to obtain a flat and uniform PFO film.

[0033] The monitoring steps are as follows:

[0034] S7: The polymer film is attached to the end face of the dual optical fiber probe 2 (eg Figure 2), dual fiber optic probes 1 and 2 are placed in parallel in the area prone to partial discharge, forming an "AND gate" system (such as Figure 3 );

[0035] The other end of the S8 dual optical fiber is connected to the QE pro spectrometer, the resolution of the spectrometer is 0.5nm, the detection range is 200-900nm, and the output signal of the spectrometer is connected and uploaded to the control system (such as Figure 4 );

[0036] S9 When a discharge occurs in the monitoring area, probes 1 and 2 have signal input at the same time, which means that a discharge occurs in the area (such as Figure 5 ).

Claims

1. A discharge monitoring method based on an organic semiconductor film, using a monitoring system for discharge monitoring, the monitoring system comprising a polymer film, a dual-fiber probe, and a spectrometer. The dual-fiber probe comprises a first probe and a second probe. The polymer film is adhered to the end face of one of the optical fibers in the dual-fiber probe. The first and second probes of the dual-fiber probe are placed parallel to an area prone to local discharge, forming an AND gate system. The other ends of the dual optical fibers are connected to the spectrometer. When discharge occurs in the monitored area, the first and second probes simultaneously receive signal inputs, indicating that discharge has occurred in that area.

Images