SU1436249A1 - A.c. electric drive - Google Patents

Description

(21) 4059392 / 24-07

(22) 04/21/86

(46) 11/07/88 „Bulle # 41

(72) L BoBirnbaum and. Bibikman

(53) 62-83: 621 (088.8)

(56) USSR Author's Certificate No. 1116511, Clo H 02 P 1/26, 1984.

USSR Author's Certificate No. 1251272, KLO H 02 R 1/26, 1985.

(54) AC ELECTRIC DRIVE

(57) The invention relates to electrical engineering. The aim of the invention is to increase the reliability of operation. The AC drive contains a power contactor, a time relay and an intermediate relay with coils 4, 10, 12, respectively. Some of the terminals of coils 4, 10, 12 are combined and connected to the second phase of the torus winding of the induction motor 1. Phases of the stator winding of the motor through contacts 5 6, 7 power contactor connected to the network. The third phase of the stator winding is connected in series with the closing contact of the Stop 2 button, the opening contact of the Start button 3 and the opening contact 13 of the intermediate relay connecting the second terminal of coil 4. The second terminal of coil 10 is connected via the closing contact 8 of the power contactor to the start button 3 and the opening contact of the Stop button 2 and the opening contact 13 and through the closing contact 9 of the power contactor with a thin connection of the buttons Stop 2 and Start 3. The second output of the coil 12 through the opening and closing The contacts 14, 15 of the intermediate relay are connected to the junction point of the contacts 8 and 9, through the closing contact 11 of the time relay - with the third phase of the stator winding, the contact 15 is bypassed by the closing contact 16 of the Stop button. The device provides start-up, shutdown and automatic restart of the induction motor 1. 1 Il.

(L

ABOUT)

Yu

The invention relates to electrical engineering and can be used in electric drives of general mechanisms.

The purpose of the invention is to increase the reliability of work.

The drawing shows a circuit diagram of an alternating current electric drive.

The AC drive contains a three-phase asynchronous electric motor 1, successively connected buttons 2 and 3, respectively, Stop and Start with self-return, a power contactor with a coil 4 and five contact contacts 5-9, Contacts 5-7 are included in the stator winding phases of the electric motor 1, The device also contains a time relay with a coil 10 and a closing contact 11 having a time delay for opening, an intermediate relay with a coil 12, two opening 1-3, 14 and one closing 15 contacts,

One terminals of coils 10, 4, 12, respectively, a time relay, a power contactor and an intermediate turnip are combined and connected to the second phase of the stator winding of the electric motor 1, the second terminal of the coil 10 of the time relay is connected through the fourth connected in series 8 and fifth 9 contact contacts of the power contactor to the common the point of connection of buttons 2 and 3, respectively, Stop and Start The second output of coil 4 of the power contactor is connected through the first disconnecting contact t3 of the intermediate relay to the free output of the Start button 3 and to the common point Fourth 8 and an additional 9 make contacts of the power contactor. The second output of the coil 12 of the intermediate relay is connected via the closing contact 15 of the intermediate relay to one output of the closing contact 11 of the time relay, which through the second break contact 14 of the intermediate relay is connected to the common connection point of the fourth 8 and fifth 9 contact closure of the power contactor. The free output of the contact of button 2 Stop is connected to the third phase of the stator winding of the electric motor 1 and to the other output of the closing contact 11 of the turn-off time, and the closing Contact 16 of the button 2 Stop is connected in parallel to the closing contact 15 of the intermediate relay. The device works as follows.

When you press the 3 start button, the coil 4 of the power contactor is energized, which activates,

Q self-locks with its short-circuit 11p1M contact 9, closes contact 8, energizes the time switch 10, and closes contacts 5-7, energizes the stator winding of the electric motor 1. The time relay triggers and by its closing contact 11 shunts button 3 Start and closes. 9 power contactor via razkazalny contact

0 14 intermediate relay. The motor 1 is turned on.

When you press button 2 Stop (to stop the electric motor 1 during its operation), coil 12 of the intermediate relay receives power through the closed closing contact 11 of the time relay and the closing contact 16 of the button 2 The relay trips, once again disconnecting the coil 4 power contactor and closing contact 11 of the time relay from button 3 Start and closing contact 9 of the power contactor, and closing contact 15, connected to the network coil 12 of the intermediate relay through the closing contact 11 of the relay temporarily

The power supply circuit of coil 4 of the power contactor and coil 10 of the time relay is broken. The contactor shuts down and opens its contacts 5-9 by disconnecting the motor 1 from the network. The time relay contact 11 remains closed for a period of time determined by a predetermined setpoint. Therefore, the coil 12 of the intermediate relay remains under voltage after releasing the BUTTON 2 Stop and opening its contact 16 "When the button 2 is released, the stop closes its 1st contact, however, the power supply to the coil 4 of the power contactor does not come as the contact 13 of the intermediate relay is open. After working out the closing time

5 of the time relay contact 11, the latter opens and breaks the power supply circuit of the coil 12 of the intermediate relay. The relay switches off and its contacts 130

five

0

five

0

15 return to the starting position. The unit is ready for the next launch.

If the mains voltage disappears or is deeply reduced during the operation of the electric motor 1, the coil 4 of the power contactor and the coil 10 of the time relay lose power. The contactor and the time relay are disconnected, the closing contacts 5-9 open. The closing contact 11 of the time relay opens with an exposure time determined by the setpoint. If the voltage in the network is restored before the time delay of the closing contact 11 has expired, then the coil 4 of the power contactor is energized again via the network - contacts 11, 14 13 - coil 4 - network. The power contactor trips, its contacts 5-9 close, energizing the stator winding of the electric motor 1 and the coil 10 of the time relay. There is sapozapuskus electric motor. Thus, the use of the invention reduces the number of transitional contacts and ensures that switching devices are switched on only in a certain sequence, which increases the reliability of the proposed device and reduces operating costs.

Claims (1)

Invention Formula AC drive containing a three-phase asynchronous electric motor, Stop button with self-resetting, closing contact and opening contact connected in series with the Start button power contactor with katutaka and five closing contacts, three ten 15 436249 of which are included in the phases of the stator winding of an electric motor, a time relay with a closing contact with an open time delay, an intermediate relay with two opening and one closing KOHTaKTat-m, the first terminals of the time relay coils, the power contactor and the intermediate relay are combined and connected to one of the phases of the stator winding of the electric motor, the second output of the coil of the time relay is connected to the common point of connection of the Stop and Start buttons via successively connected quarter and fifth make contacts of the power contactor , the second output of the coil of the power contactor through the first break contact of the intermediate The 20 relay is connected to the free start of the Start button and to the common connection point of the fourth and fifth closing contacts of the power contactor, the second output of the intermediate coil 25 relays are connected via a closing contact of an intermediate relay to one output of a closing contact of a time relay, which is connected to the common connection point of the fourth and fifth closing contacts of a power contactor via a second disconnecting contact of the intermediate relay. A free output of the disconnecting contact of the Stop button is used to connect to the other stator phase motor winding, characterized in that, in order to increase reliability, another output of the closing contact of the time relay is connected to another phase of the stator motor winding, and the closing contact of the Stop button is connected in parallel to the closing contact of the intermediate relay. thirty 35 40