CN2099967U

CN2099967U - Thermometer in transformer inner

Info

Publication number: CN2099967U
Application number: CN 91224248
Authority: CN
Inventors: 吴德范; 常敏森; 林栩; 张继元; 黄皎; 张忠学; 邓玉平; 刘建双; 张载泉; 郭连璧; 黄继昌; 丁之龙; 王祖峰; 李路珍; 赵连顺
Original assignee: Cars Locomotive & Car Research Institute
Current assignee: Cars Locomotive & Car Research Institute
Priority date: 1991-09-04
Filing date: 1991-09-04
Publication date: 1992-03-25

Abstract

The utility model relates to a thermometer in a transformer inner for measuring each point temperature (temperature rise) in a transformer. The thermometer in a transformer inner is especially suitable for the traction transformer of an electrified railway. The thermometer in a transformer inner sends out temperature rise signals from each point in the transformer by a sensor, and optical fiber is used for realizing the isolation of high and low voltage which is transferred to the ground. The power supply of a sensor circuit is transferred to the top part of the transformer from the ground by a high frequency coupling. The temperature rise signals which are sampled and treated by a computer can be directly displayed, and the temperature rise of each sensor point in the transformer are printed. The utility model has the good performance of shock resistance, water resistance, and electromagnetic interference resistance.

Description

Thermometer in transformer inner

The utility model relates to a kind of temperature test device, and inner each point temperature when being used for the measuring transformer operation is specially adapted to monitor the temperature variation under the tractive transformer running status that load variations is violent, overload happens occasionally.

At present domestic existing electric railway tractive transformer only relies on and measures oily temperature and differentiate the internal temperature situation, can't detect the temperature of Transformer Winding, iron core etc., and this is not proper.As everyone knows, the thermal time constant of transformer oil is bigger, therefore, the variation of load causes that the temperature rise of heatings such as winding, iron core variations by oil reflects just needs long period of time, that is the temperature variation of oil can not in time reflect the state of electric railway tractive transformer load, and improper overload just can not in time be handled.

Allow overload during the transformer operation, as long as in the scope that internal electrical power allows, winding temperature is no more than 140 ℃, the oil temperature is no more than 85 ℃, the transformer built-in electrical insulation is aging by normal rule, to not influence of transformer's life span, the overload under this condition, transformer itself can bear.

Designing unit considers the characteristics of traction load by existing transformer capacity design standards, often leaves bigger nargin when the capacity of selection, makes transformer often be in underload state when normal operation, causes unnecessary waste.

The purpose of this utility model is the deficiency that overcomes existing testing tool, can in time measure the inner each point temperature of transformer, as long as the each point temperature is no more than the temperature that built-in electrical insulation is sharply worn out of defined, can not excise transformer during overload and make it to continue operation, when temperature surpasses setting, can give the alarm or notify electricity to transfer to excise or to reduce loads, this is for prolonging transformer's life span, fully improve the capacity utilization factor of tractive transformer, reduce design capacity, reducing manufacturing cost etc. has positive meaning.

The technical solution of the utility model is to realize like this, the inner temperature measuring equipment of a kind of transformer, form by unit such as power supply, sensor, front-end circuit box, signal distributor, alarm, signals sampling, transmission, processing, its special character is that power unit adopts power coupler, transmits by low-pressure side voltage by the higher-order of oscillation to the high-pressure side; It is thermal sensing element that sensor adopts the metal platinum film resistance; The sampling of temperature signal, processing realize by 8031 one-chip computers; The transmission of temperature signal realizes the isolation of high and low nip by fiber coupler.

Power supply in the technical scheme and fiber coupler all are by the silicon rubber insulation submounts, are fixed on the transformer; Temperature signal is to be obtained by the oscillating impulse that sensor and front-end circuit box produce.

The utility model advantage compared with prior art is:

1, now counts dial thermometer with the transformer temperature, thermometer bulb places the top of oil, can only record the temperature on oily top, and precision is poor than the utility model, use the utility model, can measuring transformer temperature, the precision of inner any point be ± 1 ℃, and easy to use, be may observe, print temperature in the pulpit.

2, existing thermometer can not in time react the transformer load situation, overload at first is the Transformer Winding heating when taking place, because the thermal time constant of oil is bigger, when being reacted to the oil temperature variation, overload state usually disappears, use the utility model, in winding, bury sensor underground, but immediate response goes out the temperature variations of high and low pressure winding and inner each point under the overload state.

3, the winding temperature that uses the utility model to record can be realized the scientific management of transformer state maintenance, breaks unscientific periodic maintenance system, prolongs the serviceable life of transformer.

4, existing transformer overload warning is to determine according to the upper temp of oil, and warning principle of the present utility model is that a certain the temperature overshoot value that needs only in winding, oil, the iron core etc. promptly gives the alarm, and be significant to the safe operation of transformer.

Now describe the utility model embodiment in conjunction with the accompanying drawings in detail:

Fig. 1, be the structural representation of the inner temperature measuring equipment of transformer

Fig. 2, be the circuit theory diagrams of the inner temperature measuring equipment of transformer

Fig. 3, be the power coupler circuit theory diagrams

Fig. 4, be the fiber coupler circuit theory diagrams

Fig. 5, be 8031 Single Chip Microcomputer (SCM) system hardware charts

Fig. 6, interrupt routine software block diagram

Fig. 7, master routine software block diagram

Among the figure:

1, is embedded in sensor in the Transformer Winding

2, transformer porcelain vase sleeve pipe

3, sensor extension line

4, front-end circuit box

5, silicon rubber insulation submounts

6, power coupler

7, receiving circuit signal distributor

8, fiber coupler

9, Transmission Fibers

10, transformer core

11, transmission cable

12, sampling, calculating, printing, demonstration computer measurement system

13, pulpit

14, alarm

The inner temperature measuring equipment of a kind of transformer as shown in Figure 1, by power supply 6, sensor 1, front-end circuit box 4, fiber coupler 8, Transmission Fibers 9, signal distributor 7, transmission cable 11, sampling, calculating, printing, show computer system 12, alarm 14, etc. form, the physical circuit schematic diagram is seen Fig. 2.

The front-end circuit box 4 of the inner temperature measuring equipment of transformer is located at higher-pressure region, transformer top, required power supply will be supplied with from low-pressure area, need to consider the isolating problem of high and low pressure, this device adopts power coupler 6, be installed on the transformer by silicon rubber insulation submounts 5, circuit theory diagrams are seen Fig. 3, utilize high-frequency oscillating circuits that voltage is coupled to the higher-pressure region by low-pressure area, low-pressure side coupling mechanism 6 input AC 13V power supplys, rectification, mu balanced circuit device are housed in the high-pressure side coupling mechanism 6, and direct output of DC current is pressed 12V.Temperature sensor 1 in the device can be embedded in the high-low pressure winding of transformer inside, iron core and oil, tank walls etc. are located, sensor 1 among Fig. 1, be attached on the high pressure winding, sensor 1 adopts the metal platinum film resistance as thermal sensing element, this element is higher to the sensitivity of temperature, draw with outer front end circuit box 4 by transformer porcelain vase sleeve pipe 2 through resistant to elevated temperatures sensor extension line 3 and to join, it is oscillating impulse that front-end circuit produces test signal, the transmission of this signal is transmitted from transformer top high-voltage district toward the ground low-pressure area, for solving height, the isolating problem of low-pressure area, adopted fiber coupler 8, be installed on the transformer by silicon rubber insulation submounts 5, these circuit theory diagrams are seen Fig. 4, realized height, low pressure is isolated, and carry out the transmission of test signal with it, after Transmission Fibers 9 passes to ground, by signal distributor 7 each signal of measuring passage (test point) is distributed to a transmission channel p.s., enter into 8031 one-chip computer measuring systems 12 of pulpit 13 by transmission cable 11, measuring system is sampled to the signal that transmits, calculate, handle, directly on single-chip microcomputer, demonstrate the temperature of the inner each point of transformer and print immediately by printer, when the transformer internal temperature surpassed permissible value, computer system can go out alarm And by 14 of warning horns and adjust and reduce little by electricity or the excision load.Metering system can divide automatic and manual dual mode, and the maximum interval time of measurement of automated manner is 9999 seconds, extends to 65535 seconds, manual mode can be measured at any time, this device can be surveyed 99 passages at most, can measure the temperature of inner 99 points of transformer, and measuring error is in ± 1 ℃.The utility model adopts 8031 type one-chip computers, and concrete configuration is seen Fig. 5, and software block diagram is seen Fig. 6,7.

Claims

1, the inner temperature measuring equipment of a kind of transformer, form by unit such as power supply, sensor, front-end circuit box, signal distributor, alarm, signals sampling, transmission, processing, it is characterized in that power unit adopts power coupler, transmits by low-pressure side voltage by the higher-order of oscillation to the high-pressure side; It is thermal sensing element that sensor adopts the metal platinum film resistance; The sampling of temperature signal, processing realize by 8031 one-chip computers; The transmission of temperature signal realizes the isolation of high and low nip by fiber coupler.

2, temperature measuring equipment according to claim 1 is characterized in that power coupler and fiber coupler all are to be fixed on the transformer by the silicon rubber insulation submounts.

3, temperature measuring equipment according to claim 1 is characterized in that temperature signal is to be obtained by the oscillating impulse that sensor and front-end circuit box produce.