JPS5869425A - Discharge detector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a discharge detection device that detects the occurrence of a discharge state.

In high-voltage electrical equipment such as generators and transformers that handle high voltage, discharge often occurs in their internal spaces.

This discharge is harmful to electrical equipment, so
It is necessary to quickly detect the discharge and take immediate action to stop the discharge, and a discharge detection device detects the occurrence of this discharge.

FIG. 1 is a side view of the essential parts of an example of a discharge detection device commonly used in the past. It is a discharge monitoring space that monitors the
There is provided an electrical conductor (3) held by 2). A high voltage is constantly or intermittently applied to this electrical conductor (3). 4 is an optical fiber as an optical transmission line, with one end exposed in the discharge monitoring space (1) and the other end connected to a photodetector 5 provided outside the electrical equipment; (6) and (7) are optical fibers as an optical transmission line; It shows a discharge occurring in an electrical conductor (3) within the discharge monitoring space (1).

In the discharge detection device configured as described above, when a discharge (6) occurs in the discharge monitoring space (1), the light emitted by the generation of this discharge (6) is transmitted through the optical fiber (4).
) is taken in from the light receiving end (4a) and transmitted to the photodetector (5). The photodetector (5) photoelectrically converts the light emitted by the discharge supplied via the optical fiber (4),
When the converted output exceeds the reference value, it is assumed that a discharge has occurred, and a discharge detection signal is sent out.

However, the propagation characteristics of the optical fiber used in the discharge detection device with the above configuration are as follows: ``As shown in Figure 2, the attenuation increases toward the shorter wavelength region, whereas the light emitted by the discharge is emitted at shorter wavelengths. This makes it impossible to propagate over long distances and monitor remotely. Also,
In the above configuration, the light receiving end (4) of the optical fiber (4)
a) Since it is simply exposed to the discharge monitoring space, its aperture angle (8) is narrow and it is difficult to detect the discharge (7) generated outside the aperture angle (8). However, it has various drawbacks, such as the fact that the monitoring range is narrow as a result.

This invention has been made in view of the above-mentioned drawbacks of the conventional devices, and includes a long light receiving member arranged to receive light generated by discharge from a curved surface, and an optical transmission path that guides the light to the bulb. Accordingly, it is an object of the present invention to provide a discharge detection device that has a wide discharge state monitoring range and has little propagation loss of detection light.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.

FIG. 8 is a side view of essential parts showing an embodiment of the discharge detection device according to the present invention. In the figure, (9) is an elongated member formed in the shape of a rod or fiber containing a fluorescent substance inside. The elongated member (9) is provided in front of the light receiving end (4a) of the optical fiber (4) forming an optical transmission path, and the tip end (9a) is connected to the optical fiber via the optical coupling part 0Q.
(4) is connected to the tip (4a).

As a result, as will be explained later, the long wavelength light that has propagated through the elongated member (9) propagates through the optical fiber (4) via the optical coupling section αQ and reaches the photodetector section (5). reach

A lens or the like may be used in the coupling portion (2) in order to increase the optical coupling efficiency. In FIG. 5, a rod-shaped or fiber-shaped transparent phosphor elongate member (9) is placed inside a quartz tube with an inner diameter of 1 gmm and an outer diameter of gmm, and is made of a liquid solution prepared by adding Rhodamire 6G to a solution of acrylic in ethyl acetate m2. A device filled with phosphor was used. The emission spectrum of this phosphor is as shown in Figure 4.
5800A when receiving short wavelength light from 800 to 4200 people
It emits long wavelength light with a peak at ~5500A.

A portion (2) of the light emitted from this phosphor is shown in Figure 5 (
As shown, the incident light from the narrow surface of the elongated member (9) propagates within the rod-shaped or fiber-shaped transparent fluorescent substance, is collected at its tip (9a), and is focused on the eyepiece provided at the coupling part 00. The light passes through the lens AP, propagates through the optical fiber (4), and reaches the photodetector (5).

In the discharge detection device configured in this way, w! , (6), (7> occur, and due to this discharge (6), (7), 8800 ~
When the short wavelength light of 4,200 people is generated, the entire adhesive surface of the elongated light-receiving member (9) containing the phosphor extends into the discharge monitoring space (1) and is exposed. In addition, the device is exposed to light emitted by the discharge generated over a wide range. In this case, the phosphor 9 emits light when excited by the short wavelength light, regardless of the side light coming from any direction, so the acceptance angle as a whole is greatly expanded compared to the conventional one. This means that the light emitted by the discharge (7) is also reliably sensed. Since the elongated light receiving member (9) containing the phosphor is optically coupled to the light receiving end (4a) of the optical fiber (4), the light emitted from the elongated light receiving member (9) containing the phosphor is transmitted through the optical fiber. The light is efficiently collected at the light receiving end (4a) of (4) and propagated to the light detection section (5). In this case, the elongated light-receiving member (9) containing the phosphor converts the short-wavelength light emitted by l[(6), (7) into long-wavelength light and converts it into the optical fiber (4).
), it constitutes an optical wavelength conversion section that supplies the
Along with this, the propagation characteristics of the optical fiber (4) as an optical transmission path are significantly improved.

For example, if the wavelength of the discharge light is 4000 and the wavelength of the light emitted from the fluorescent material is 5400, the attenuation will decrease from 40 dB to 20 dB when propagating through 1 km of the optical fiber 4, as shown in Figure 2. 1. Therefore, in the above configuration, it becomes easy to provide the photodetector (5) at a long distance.

In the above examples, Rhodashin 6G dispersed in acrylic was used as the fluorescent substance, but the present invention is not limited thereto, and other liquid transparent fluorescent substances may be used. good. In this case, the phosphor generally does not pose any problem since it emits light with a wavelength longer than the wavelength of light it receives.

Although the apparatus of the above embodiment detects discharge light, it is of course possible to apply the present invention to various types of detection other than discharge light.

As described above, according to the present invention, the elongated light receiving member is arranged to receive light generated by discharge from the circumferential ml, and the light radiated from the end face of this elongated light receiving member is guided for detection. Since the light transmission path is provided, the elongated light-receiving member is not illuminated with respect to the emitted light that is generated in a wide range, so that the range in which discharge light can be detected can be widened. Also,
The light received by the long light-receiving member is collected at the end face of the long light-receiving member and radiated through the optical transmission path, which has the effect of improving the propagation characteristics of the light received by the long light-receiving member.

[Brief explanation of the drawing]

FIG. 1 is a side view of a main part showing a conventional discharge detection device, FIG. 2 is a diagram showing transmission characteristics of various optical fibers, and FIG. 8 is a side view of a main part showing an embodiment of a discharge detection device according to the present invention.
FIG. 4 is a diagram showing the light emission characteristics of the phosphor, and FIG. 5 is a side view of the main part showing another embodiment of the present invention. Identical parts in the figures are represented using the same symbols. (1) is a discharge monitoring space, (3) is an electric conductor, (4) is an optical fiber that is a photoelectric transmission path, (4a) is a light receiving end, (5
) indicates a photodetection section, (6) and (7) indicate discharge, (8) indicates an aperture angle, (9) indicates a long light receiving member, and (9a) indicates an end surface. Agent Makoto Kuzuno - Figure 1 Figure 3 Figure 2 Kencho (μ)

Claims (3)

[Claims] (1) A discharge detection device equipped with a long light receiving member arranged to receive light generated by discharge from a curved surface, and an optical transmission path that guides the light radiated from the end face of this long light receiving member to detect it. . (2) The elongated light-receiving member is formed into a rod-like or fiber-like shape that contains a fluorescent substance that converts short-wavelength light into long-wavelength light. Discharge detection device described in Section 1. (3) The discharge detection device according to claim 2, characterized in that the fluorescent material is an organic solvent in which acrylic is dissolved and A-Dan 6G is added thereto.