SU1675964A1 - A method of checking the wear of high-voltage relaxing setting - Google Patents

Abstract

The invention relates to electrical engineering, in particular to methods and devices for checking the electrical characteristics of relay protection. The aim of the invention is to simplify and shorten the verification time. The test method consists in supplying current from the current source to the current protection circuits and fixing the value of this current at the instant of tripping. The test is carried out at the working secondary current without disconnecting the connection from work by briefly increasing the voltage at the input of the reactive protection unit compared to the actual voltage corresponding to the given operating current in accordance with the conversion factor equal to the ratio of the set current to the operating current at the time of the test . 3 il. (Ls

Description

 The invention relates to electrical engineering, in particular to methods and devices for checking the electrical characteristics of relay protection.

The purpose of the invention is to simplify and shorten the inspection time.

FIG. 1 shows a block diagram of a device for implementing the proposed method when checking the characteristics of current protection; in fig. 2 is a block diagram of a device for implementing the proposed method when checking the characteristics of distance protection; in fig. 3 is a block diagram of a device for implementing the proposed method when checking the characteristics of power direction organs.

The installation contains a high-voltage current transformer 1, an input converter 2, an input signal control element 3, a protection setting control element 4, a reactive protection element 5, an alarm element 6. The input control element 3 consists of a voltage divider in the form of a potentiometer 7 and a resistor 8 with a control button 9.

To check the health of the current protection at the operating current load checked

VI

with che about

.N

with her work at conversion factor

v "U + Us ly

CP n,,,

where uy. Us are the voltages taken from potentiometer 7 and resistor 8, respectively;

1U, 1H are the setpoint currents for protection and load, respectively.

The load current of the monitored device can be measured with the help of the device VAF-85 without breaking the current circuits or with the help of an ammeter connected to the secondary current circuit of the current transformer 1. The voltage across the resistor 7 and the sum of the voltages taken from potentiometer 6 and resistor 7 can be measured with a voltmeter at the input terminals of potentiometer 3. By changing the position of the setpoint adjustment element slider 4, the response setting of the reactant 7 can be changed, which can be checked similarly to the above .

The response of the response organ 5 is monitored by the signaling element 6.

The diagram of the device shown in FIGS. 2 contains current transformers 10 and 11, current converter 12, voltage transformer 13., input converter 14, control elements for setting the current setpoint 15 and voltage 16, reactive distance protection body 17, alarm element 18 and an input control element 19 consisting of a potentiometer 20, a resistor 21, a potentiometer 22, and a control button 23.

In order to verify the correctness of the setpoint for the tripping resistance, the current and voltage signal conversion factors are set using potentiometers 20 and 22. The remote unit tripping is monitored using the alarm element 17.

The choice of current and voltage conversion factors is made by

Zc

Zh

KiK2

where Zc is the response resistance of the reacting organ, as determined by the angle of the load current;

ZH is the load resistance at the time of testing the response of the reacting organ;

Ki, K2 are the current and voltage conversion factors, respectively, and

to U20 + U21 1y

1U21 and

U20, U21 are the voltages taken from potentiometer 20 and resistor 21, respectively;

K9 U1-Un K2

where Ui is the voltage across the control element 16 taken from the slider of the potentiometer 22;

U2 is the voltage across the control element 16 taken from the input terminals of the potentiometer 22;

Uy, UH are the setpoint and load voltages, respectively.

Measurement of current and voltage protection supplied to the converters of the tested protection, as well as the angles between the currents and

voltages can be made without breaking current circuits using a VAF-85 device.

When changing the settings for the resistance of operation with the help of elements 14

and 15 adjustment, the correctness of the setpoint can be checked in the same way as the above. The layout of the device shown in FIG. 3, contains current transformers 22 and 23,

current input converter 24, voltage transformer 25 input voltage converter 26, current setpoint control elements 27 and voltage 28, power direction regulator 29, alarm element 30, input current divider consisting of a potentiometer 31 and a resistor 32, control buttons 33 and 34. To check the power direction of the power, its current sensitivity can be changed using the divider 31, 32 and the button 33 in the same way as checking the current reacting organ. Pressing the button 34 causes the switching (triggering or returning) of the power direction organ, which is signaled by the alarm element 30.

The use of this method for testing relay protection provides a significant reduction in the testing time and improves the reliability of the protection operation, making it possible to test the protection without breaking the input protection circuits.

Claims (1)

Invention Formula The method of checking the setpoint of operation of relay protection of high-voltage connections, which consists in supplying current from a current source to current protection circuits and fixing the value of this current at the moment of actuation, characterized in that, in order to simplify and shorten the test time, test the setpoint response 0 produced at the working secondary current without disconnecting the connection from work by briefly increasing the voltage at the input of the reactive protection unit in comparison with the actual voltage corresponding to the given operating current in accordance with the conversion factor equal to the ratio of the set current value to the operating current at the time of the test. A b ABC 2 FIG. 3