SU1323791A1 - Device for controlling ferropowder electromagnetic brake - Google Patents

Abstract

The invention relates to a technique for controlling electromagnetic ferropowder brakes of drilling rigs and can be used in drive systems for launching and lifting units to provide automatic tool descent modes and maintain the load on the bit during drilling. The purpose of the invention is to provide an automatic braking mode in accordance with the descent program while improving the accuracy of maintaining a given speed in transient modes. During the descent of the column in the descent program block, a signal is generated corresponding to a given speed. After the first limit switch is triggered, this signal starts to decrease linearly to the pre-speed level. Then the limit stop switch is activated and sends a signal to the mechanical brake control unit. In the period from the beginning of the descent of the column to its stopping, a control signal is generated at the output of the summation unit. With a positive signal, the thyristor regulator of the excitation current is switched on and at the same time passes the maximum current into the excitation winding by a ferroporised brake. The resulting braking torque reduces the current descent rate of the column to a value that ensures that the control voltage at the output of the summation unit is equal to zero, and the diode-thyristor controller is turned off. When the descent rate is repeatedly exceeded, the control voltage becomes positive again and the operation of the circuit is repeated. 1 il. S (L with to 00

Description

The invention relates to a technique for controlling electromagnetic ferropowder brakes of drilling rigs and can be used in drive systems for launching units to provide automatic tool lowering modes and to maintain the load on the bit during drilling.

The aim of the invention is to provide an automatic braking mode in accordance with a descent program while improving the accuracy of maintaining a given speed in transients.

The drawing shows a block diagram of the proposed device.

The device comprises a tachogenerator 1, a limit switch 2 start of the braking distance, a limit stop switch 3 of exact stop, a mechanical brake control unit 4, a differentiation unit 5, a descent program unit 6, a summation unit 7, a thyristor diode controller 8, a ferro-powder brake excitation winding 9, block 10 set load.

The output of tachogenerator 1 is connected to the input of differentiation unit 5 and the second input of summation unit 7, the first input of summation unit 7 is connected to the output of differentiation unit 5, the third input of summation unit 7 is connected to output of descent program block 6, and the output of summation unit 7 is connected a diode thyristor regulator 8 of the excitation current, with one input of block 6 of the program of descent associated with the limit switch 2 of the start of the stopping distance, and the second input of block 6 of the program of descent and block 4 of controlling the mechanical brake through the end- The second precision stop switch 3 is associated with the automation system for tripping a drilling rig.

The device works as follows.

If necessary, the descent of the column from the automation system for tripping operations receives two signals: one to block 6 of the descent program, and the other through the closed limit switch 3 to block 4 to control the mechanical brake (not shown). The brake opens and the column (not shown) starts to move down. At the same time, the output voltages of the current speed (C / t) from the tachogenerator 1, differentiation unit 5 (From), unit 6 of the descent program (1Gz) go to summation unit 7. The descent program is formed in block 6 of the descent program in the form of a voltage Uj in magnitude corresponding to a given column velocity. With the passage of the column zone limit switch 2, it is triggered, and at the output of block 6 of the descent program, the voltage Uj begins to linearly decrease to the level of the provisional speed. When the column enters the zone of the limit switch 3 exact stop, it is triggered and sends a signal to the mechanical control unit 4

brake, the brake is closed, ensuring the column is stopped. In this case, during the period from the beginning of the descent of the column to its stopping, a control voltage is generated at the output of the summation unit 7 (Jy J-U + and. When the diode-thyristor regulator 8 of the excitation current is turned on and passes the maximum current to the winding 9 ferroforder brake. The resulting braking torque reduces the current descent rate

columns to a value that ensures that the control voltage is zero at the output of summation unit 7, and the diode thyristor controller is turned off. When the descent rate is repeatedly exceeded, the control voltage again

0 becomes positive (), and the operation of the circuit is repeated.

The proposed device provides automatic braking in accordance with the program of my descent while increasing the accuracy of maintaining the given speed in transient conditions.

Claims (1)

Invention Formula A device for controlling an electromagnetic ferropress brake brake rig containing a tachogenerator, a diode-thyristor regulator of the excitation current covered by feedbacks in speed and load, the excitation winding of the ferroporoschnogo brake, characterized by the fact that in order to provide an automatic braking mode and increase the accuracy of maintaining a given speed in transient conditions, the device is equipped with a differentiation unit, a unit 0 of the descent program, summation unit, mechanical brake control unit, limit stop switches and stopping switches, with the output of the tachogenerator connected to the input of the differentiation unit and to the second input 5 of the summation unit, the first input of the summation unit is connected to the output of the differentiation unit, the third input of the summation unit is connected to the output of the descent program block, and the output of the summation unit  is connected with a diode-thyristor regulator of the excitation current, with one input of the descent program block connected with a limit switch. the beginning of the stopping distance, and the other input of the descent program block and the mechanical brake control unit Precision stop limit switches are associated with the rig automation system. , .0. f / n Db-fHH Hx From the Automation System  / 7