SU1524149A1 - Device for controlling induction motor - Google Patents

Abstract

The invention relates to electrical engineering and can be used in electric drives of a transformer voltage control device under load. The aim of the invention is to improve the reliability of the device. The goal is achieved by the introduction of the second and third closing contacts 25, 26 of the auxiliary relay, the opening contact 32 of the position switch, the closing contact 22 of the intermediate relay. The position switch is mechanically connected to the motor shaft 1. When contact 27 of the two-position switch is closed, the two-position relay with the coil 9 is activated. Contact 26 keeps the coil 23 of the auxiliary relay in the on state. Pin 24 includes a coil 14 of the brake relay. The contacts 2 of the contactor connect the electric motor 1 to the power supply. After turning on the engine, the position switch is activated, the contacts 30 and 31 of which open and the contact 32 closes. Contact 30 turns off the power circuit coil 16, and then contact 17 turns off the coil 14 of the brake relay, providing braking for the electric motor. 1 il.

Description

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The invention relates to electrical engineering and can be used in electric drives of a transformer voltage control device under load.

The aim of the invention is to improve the reliability of the device.

The drawing shows a circuit diagram of the device;

The device for controlling an induction motor contains an electric motor 1, three normally open contacts 2 of the power contactor, disconnecting contacts 3 and 4, and normally open contacts 5 and 6 of the two-position relay, two disconnecting contacts 7 and 8 of the braking relay.

The motor control circuit contains a two-position relay with a coil 9 with opening 10 and 11 and closing 12 and 13 contacts, a brake relay with a coil 14 with closing contact 15, a power contactor with a coil 16 and closing 17 and opening 18 contacts, an intermediate relay with a coil 19, two closing contacts 20 and 21 and opening contact 22, auxiliary relay with coil 23, closing contacts 24-26, two-position switch with the first 27 and second 28 fixed outputs and movable contact 29, positional switch with closing 30 and 31 and opening 32 contacts 32, contact 33 of the mode selector

Three closing contacts 2 of the contactor are included in the stator winding circuit of the electric motor 1, two break contacts 7 and 8 braking relays with the I4 coil are connected to the two phases of the stator winding of the electric motor 1, and their other terminals are combined and connected to the third phase of the stator winding. One input of the fourth closing contact 17 of the contactor of the contact 32 of the mode switches, two closing contacts 30 and 31 of the position switch and the moving contact 29 of the two-position switch are combined and intended to be connected to the output of the power source. The third view of the coil 9 two-position relay and one terminals of the coils 14, 19, 23 and 16 of the remaining relays and the power contactor

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connected together and designed to be connected to a different power supply terminal.

One fixed display 27 of the two-position switch is connected via the first disconnecting contact 10 to the two-position relay and is connected to the first coil of the coil 9 of the two-position relay and through its first closing contact 13 is connected to one of the first contact of the intermediate relay 20 with the coil 19, another fixed output 28 of the two-position the switch through the second closing contact 12 of the two-position relay is connected to the second view of the coil 9 of the two-position relay and through its second disconnecting contact 11 is connected to one in vodom first switching contact 20, an intermediate relay, the other terminal of the first switching contact 20 connected to the other coil 19 vshodom intermediate relay. The other end of the fourth make contact 17 of the contactor is connected to the other end of the coil 14 of the brake relay. The other output of the mode switch contact 33 is connected to one output of the second closing contact 21 of the intermediate relay, and the other output of contact 21 is connected to another input of the first closing contact 30 of the position switch and through the closing contact 15 the braking relay is connected to the other output of the coil 16 of the power contactor. One step of the first closing contact 26 is connected to the other end of the coater 23 of the auxiliary relay. Third, fourth and fourth 5, 6 opening and closing contacts of the two-position relay 9 form two pairs of reversing contacts in the stator winding of the electric motor 1.

The power contactor is additionally equipped with one opening contact 18, the intermediate relay is equipped with the opening contact 22, the auxiliary relay is equipped with the second 24 and third 25 closing contacts. Some outputs of the second 24 and third 25 make contacts of the auxiliary relay are connected to another output of the coil 14 of the braking relay. Another output of the second closing contact 24 of the auxiliary relay is connected to one output of the closing contact 20 of the intermediate relay, and the other output is third 515

its closing contact 25 of the auxiliary relay is connected to another closing contact 15 of the braking relay and with one of the opening contacts 18 and 22 of the contactor and the intermediate relay, another opening of the intermediate contact 22 of the intermediate relay is connected to one output of the first closing contact 20 of the intermediate relay, The other side of the opening contact 18 of the power contactor is connected to another output of the coil 23 of the auxiliary relay. The other terminal of the first closing contact 26 of the auxiliary relay is connected to one output of the opening contact 32 of the position switch, the other output of the opening contact 32 is connected to one output of the contact 33 of the mode switch.

The device works as follows.

When the fixed contact 27 of the two-position switch is closed, the current flows through the contact 10 and the coil 9 of the de-positioning relay. The two-position relay is activated, its contacts 3, 4, 10 and II open, and its contacts 5, 5, 12 and 13 close-c. On the circuit, the output 27 of the on-off switch - contact 13 of the two-position relay - contact 22 of the intermediate relay - contact 18 of the contactor turns on the coil 23 of the auxiliary relay and the contacts 24-26 of the auxiliary relay close. The contact 26 keeps the auxiliary turnip coil 23 in the on state.

Contact 24 turns on the braking relay coil 14, while the braking relay contacts 7 and 8 disassemble the braking circuit of the electric motor 1, the braking relay contact 15 closes the circuit from pin 27, contacts 13, 24 and 25 to turn on the contactor coil 16. The contacts 2 of the contactor connect the electric motor 1 to the power source, the contact 17 of the contactor connects to the power source the coil 14 of the brake relay and through the contacts 25 and 15 the coil 16 of the power contactor. Contact 18 of the contactor opens the switching circuit of the auxiliary relay coil 23. The duration of the contact closure of a two-position switch should be longer than the time for switching on the auxiliary relay, the braking relay and the contactor. Through some

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After the motor 1 is turned on, it triggers the position switch mechanically connected to the output shaft of the motor 1. The KOH-J cycle 30 position switch connects the coil 16 of the power contactor to the power supply, pin 3 of the position switch turns on coil 19 of the intermediate relay, and pin 32 of the position switch turns off the coil 23 of the auxiliary relay. The auxiliary relay contacts 24 and 25 open the deceleration relay and contactor on circuit, the auxiliary relay contact 26 opens the auxiliary relay coil 23 holding circuit. The contacts 20 and 21 of the intermediate relay are closed, and the contact 22 of the intermediate relay is opened. Contacts 21 and 20 are designed to implement step-by-step and continuous switching modes, and contact 22 disassembles the activation circuit of the coil 23 of the auxiliary relay. After opening the contacts 24 and 25 of the auxiliary relay, the coil 16 of the power contactor is held in the on state by the contact 30 of the position switch, and the coil 14 of the braking relay by the contact 17 of the contactor. At the end of the switch, the position switch is triggered, contacts 30 and 31 of which open and contact 32 close. Contact 30 turns off the power contactor coil 16, and then contact 17 of the contactor turns off the coil 14 of the braking relay, providing braking to the electric motor 1. The device is ready to work out the next command set by the contacts of the two-position switch. The adjustment of the device to a fixed position during power interruptions during the switching process is ensured by a contact 18 of the contactor. When the power is interrupted during the switching process, the device has stopped in the intermediate position, while the contacts 30 and 31 of the position switch are closed. When a supply voltage occurs, the auxiliary relay coil 23 is turned on in a circuit from terminal 30. A position switch and contactor terminal 18. The auxiliary relay contact 25 turns on the brake relay coil 14, the contact 15 of which turns on the power contactor coil 16.

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ensuring that the motor 1.

Thus, the introduction into the device of the second and third closing contacts of the auxiliary relay, the disconnecting contact of the position switch, the disconnecting contact of the intermediate relay ensures the elimination of device malfunctions, terminating in arbitrary switching of the device to the end position. Thus, when the coil 23 circuit is broken, the auxiliary relay does not turn on and the open contacts 24 and 25 prevent the activation of the coil 14 of the brake relay and the coil 16 of the power contactor, excluding the operation of the electric motor 1.

The introduction of the opening contact 18 of the contactor preserves the function of fine-tuning the motor 1 to a fixed position of the device during power failures in the process of switching the device.

The application of the invention makes it possible to increase the reliability of the device by eliminating failures, which is achieved by changing the order of the operation of the relay and replacing the device in the starting circuit, Q break contacts

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Claims (1)

Invention Formula switch and is provided with an output for connecting to a different terminal of the power supply, a two-position relay with a coil and four closing and four normally closed contacts, an auxiliary relay with one closing contact, an intermediate relay with two closing contacts, a movable output of the two-position switch is connected to one output contact of the mode switch one fixed output of the two-position switch through the first break contact of the two-position relay is connected to the first output of the coil two-way position relay and one output of the first closing contact of the two-position relay, another fixed output of the two-position switch, through the second closing contact of the two-position relay connected to the second output of the coil of the two activation relay and one output of its second normally open contact, the other outputs of the first closing and second disconnecting contacts two-point relay combined into a common point, the third output of the coil of the two-position relay is connected to one of the terminals of the brake relay coil, two pairs of roars rsivnyh contacts for the two phases of the stator winding of the motor are in the form of third and fourth concentrations of NO and NC apparatus for controlling asynchronous, switch-off cycles, one vy20 25 The fourth contact of the power contactor is connected to one contact of the position switch, the other end of the fourth closing contact of the power contactor is connected to another end of the braking relay coil, one end of the closing contact of the brake relay is connected to another end of the coil of the power contactor, the other end contact of the brake relay through the first closing contact of the intermediate relay is connected with another contact of the mode switch contact and with the other output of one contact position switch, common point of the other conclusions of the first closing and second disconnecting contacts of the two-position relay through the second closing contact of the intermediate relay is connected to one end of the coil of the intermediate relay, the other end of which is combined with one end of the auxiliary coil motor, containing a power contactor with a coil and closing contacts, three of which are intended to be included in the phase circuit of the stator winding of the electric motor, and one end of the power contactor coil is provided with a pin for connecting to one of the power supply terminals, a braking relay with a coil and one closing and two break contacts, one output of the coil of the brake relay is connected to one view of the coil of the power contactor, and two break contacts of the brake relay with one of the terminals intended for Attaching the two phases of the stator windings of the motor, and their other vyvo rows are combined and are intended for connection to the third phase of the stator winding, the position switch with two normally open contacts, the mode switch, one terminal contact which is combined with one of the two pin contacts positioner eight switch and is provided with an output for connecting to a different terminal of the power supply, a two-position relay with a coil and four closing and four normally closed contacts, an auxiliary relay with one closing contact, an intermediate relay with two closing contacts, a movable output of the two-position switch is connected to one output contact of the mode switch one fixed output of the two-position switch through the first break contact of the two-position relay is connected to the first output of the coil two-way position relay and one output of the first closing contact of the two-position relay, another fixed output of the two-position switch, through the second closing contact of the two-position relay connected to the second output of the coil of the two activation relay and one output of its second normally open contact, the other outputs of the first closing and second disconnecting contacts two-point relay combined into a common point, the third output of the coil of the two-position relay is connected to one of the terminals of the brake relay coil, two pairs of roars rsivnyh contacts for the two phases of the stator windings of the motor are in the form of third and fourth contacts make and break-off relays, one vy0 45 „55 The fourth contact of the power contactor is connected to one contact of the position switch, the other end of the fourth closing contact of the power contactor is connected to another end of the braking relay coil, one end of the closing contact of the brake relay is connected to another end of the coil of the power contactor, the other end contact of the brake relay through the first closing contact of the intermediate relay is connected with another contact of the mode switch contact and with the other output of one contact position switch, common point of the other conclusions of the first closing and second disconnecting contacts of the two-position relay through the second closing contact of the intermediate relay connected to one end of the coil of the intermediate relay, the other end of which is combined with one end of the coil of the auxiliary relay and connected to one end of the power contactor coil, t l and aa so that, in order to increase reliability, the power contactor is additionally equipped with one break contact, the intermediate relay is equipped with a closing contact, the auxiliary relay is provided with second and third closing contacts, the position switch is equipped with an opening contact, one terminals of the second and third closing contacts of the auxiliary relay are connected to another output of the braking relay coil, another second-close terminal of the auxiliary relay is connected to one output terminal of the intermediate relay and the other end of the third make contact of the auxiliary relay is connected to the other end of the close o five 0 contact of the braking relay and some of the opener contacts of the power contactor and the intermediate relay, another output of the open contact of the intermediate relay is connected to the common point of the other terminals of the first closing and second disconnecting contacts of the two-position relay, and the other output of the contact contact of the power contactor is connected to another output coil auxiliary relay and through the first closing contact of the auxiliary relay is connected to one output of the disconnecting contact of the positional switch ents, vshod other of which is connected to one terminal of the mode switch, the other terminal of relay coil is connected to an intermediate vshodon other second switching contact of the switch position.