JPS6119106A - Insulator deterioration monitoring device - Google Patents

Abstract

PURPOSE:To enable to effectively diagnose the deterioration of an insulator by a method wherein a data processing part is provided for the purpose of detecting the deterioration of the degree of polymerization of the insulator of an electric machine. CONSTITUTION:After the temperature value of the transformer 1 inputted from a temperature sensor 2 has been converted into a digital value using an A/D converter 31, a temporal integration is performed by a data processing part 3 using a CPU32, and the degree of polymerization of the insulator located in the transformer 1 is calculated by comparing the result of the above-mentioned time integration with the integration degree-by-time/temperature integration curved line which is memorized in a memory storage 33 in advance. The decision of the termination of life is given at the point of time when the insulator reaches the level of the degree of polymerization which is determined as the dangerous value in advance. The decision indicates the consumption life of the insulator, the remainder of its life, the load time which can be had in the future and the like in addition to the finishing point of life. As a result, a substantial decision of deterioration can be given, and the instruction and control of operation such as an overloading operation and the like can also be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an insulator deterioration monitoring device that monitors the deterioration of an insulator in electrical equipment such as a transformer and predicts its life.

In oil-filled electrical equipment, insulating oil and insulating paper are used as insulators. In the case of insulating oil, the lifespan can be extended by sampling and measuring the pressure resistance value, etc., and replacing it with new oil if it has deteriorated, but in the case of insulating paper, it is difficult to replace it. If this happens, it will be completely dismantled and cannot be replaced, and it can be said that the lifespan of electrical equipment is determined by the deterioration and lifespan of the insulating paper.

[Prior art]

Conventionally, the g-anomaly has been known as a method for estimating the deterioration of insulating paper, and is used in operating guidelines for transformers and in methods for calculating life loss by integrating temperatures.

However, life prediction using this method is a relative comparison of life with 30 years of operation as 100, and although it plays a large role as a guideline for operation and maintenance,
There are some that have been in operation for more than 0 years, and there was a drawback that it was not possible to determine substantial deterioration or lifespan.

[Summary of the invention]

This invention was made to eliminate the above-mentioned conventional drawbacks, and by calculating the degree of polymerization of the insulating paper by integrating the operating temperature, it is possible to determine the substantial deterioration and lifespan of the insulating paper of electrical equipment. The purpose is to provide an insulator deterioration monitoring device.

The deterioration of insulating paper is that the physical properties of the paper change with operating history and the insulating strength is affected. Physical properties include degree of polymerization, tensile strength, bursting strength, bending strength, etc., but recent research has revealed that the degree of polymerization is the main factor; when the degree of polymerization falls below a certain level, , the paper is easily torn due to vibrations, etc., significantly reducing insulation performance.

In addition, oxygen and heat are the main factors that affect the degree of polymerization of insulating paper, but in the case of transformers, air is not directly exposed to the insulating oil, so oxygen is It is not supplied, and the main factor in the deterioration of the degree of polymerization can be considered to be heat, and the main factor is the temperature to which the insulating paper is exposed.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

In the figure, 1 is an electrical device such as a transformer, 3 is a temperature sensor that detects the temperature of the transformer 1, and 3 is a measuring resistor.
is a data processing unit connected to the temperature sensor, and an analog/digital converter (A/D) that converts the analog temperature value input from the temperature sensor into a digital temperature value;
? /, arithmetic means, for example, a CPU 3λ and a memory 33. DA is a display unit connected to the data processing unit 3 to externally display how long the life span is.

In the insulating material deterioration monitoring device having this 51C configuration, the data processing section 3 converts the temperature value input from the temperature sensor into an A/D converter.
After conversion in step 31, time integration is performed using K, +C'P, iU Jλ, and comparison is made with the degree of polymerization vs. temperature time integral curve of FIG. 1 stored in advance in the memory 33. The degree of polymerization is calculated from K. The lifespan is determined when the degree of polymerization reaches a level that has been set as a dangerous value in advance, and in addition to the end of life, consumption life, remaining life, possible future load time, etc. are displayed.
In addition to being able to make substantial deterioration judgments, it is also possible to manage driving instructions such as overload driving.

In addition, if there are large fluctuations in the load factor, if the control of the cooler changes from the operation trap, or if there is a temperature distribution of insulation, there are two methods, in addition to directly embedding a temperature sensor unit in the target location. It is possible to estimate the temperature distribution by inputting and calculating the load factor and cooler operating status, and by performing various experiments, so by targeting several points, it is possible to calculate the degree of polymerization without compromising accuracy. .

In addition, when monitoring insulation materials during operation,
It is necessary to initialize the degree of polymerization of the insulating material of electrical equipment, so measure the polymerization k by sampling a part of the insulating material such as a hot water bath for internal inspection, and set the initial value. It has the same effect on the operating status and life deterioration determination.

The data processing section may be installed exclusively in each electrical device in the transformer, or a plurality of transformers and electrical devices may be grouped together and 7 data processing sections may be installed.

〔Effect of the invention〕

As described above, according to the present invention, a data processing unit is provided to determine the decrease in the degree of polymerization of insulators in electrical equipment such as transformers, which makes it possible to effectively diagnose the deterioration of insulators and to It also has the effect of making management more effective.

[Brief explanation of the drawing]

FIG. 1 is a graph showing a degree of polymerization versus temperature and time integral curve of an insulator, and FIG. 2 is a block diagram showing an embodiment of the present invention. 1 is a transformer, 1 is a temperature sensor, 3 is a data processing unit, DA is a display unit, 31 is A/L), and J is a CPU. 33 is a memory.

Claims (3)

[Claims] (1) A temperature sensor that measures the temperature of electrical equipment, a memory in which a predetermined insulator polymerization degree versus temperature time integral curve is memorized in advance, and a temperature value input from the temperature sensor is integrated over time and An insulating material deterioration monitoring device comprising: a data processing unit having a calculation means for determining a deterioration of the insulating material by comparing the curve with a curve to determine a decrease in the degree of polymerization of the insulating material in the electrical equipment. (2) The insulating material deterioration monitoring device according to claim 1, wherein the data processing section receives input of an overload operating state, a load factor, or a cooler operating state of the electrical equipment. (3) The insulating material deterioration monitoring device according to claim 1 or 2, wherein one data processing section is installed for a plurality of electrical devices.