SU1029364A1 - Device for automatic confinement of pump unit shaft - Google Patents

Description

At the maximum second contact of a 1 029364 current, a bypass intermediate relay, is connected to another output of the intermediate relay coil.

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The invention relates to electrical engineering and can be used in devices for automatically holding the shaft of a pumping unit driven by synchronous or asynchronous electric motors during the period of discharge of the discharge pipeline.

A device for automatically holding the shaft of a pumping unit is known, which comprises an asynchronous motor with a phase rotor, a start switch with two groups of contacts, one of which is directly connected to the phases of the stator windings, and the other through resistors, a brake switch, a direct current source, through the contacts of the brake switch and the contact of the start switch is connected with the output of one of the phases of the stator winding and its zero output, and the output of the phase of the stator winding through 1) an ezistor, another source output d.c. track brake switch connected to one phase of the rotor winding, wherein the second phase through the contact switch is connected to the third braking-phase stator winding. Resistors are introduced into the phase circuit of the rotor winding. In this device, the electric motor is transferred to a reduced speed by opening / stator windings of it from the network and connecting additional resistors to the stator and rotor windings circuit, and when the mechanism approaches at a reduced speed to the desired position of the exact stop switch In series, two stator and two rotor windings are connected in a constant current f1J.

However, when using this device to hold the shaft of the pump unit in a fixed position, the reliability of operation is sharply reduced, since the reduction in speed when the mechanism approaches the fixed position occurs with greater

acceleration, which makes it difficult to determine when voltage is supplied to the stator windings and. the rotor, under the action of which braking of the electric motor is provided,

The closest technical solution to the proposed device is the DLI automatic holding of the pump shaft; an assembly containing an AC electric motor, a start switch, contacts of which are included in the stator winding phases of the electric motor connected in series with the Stop button, and the Start button bypassing the start switch, a direct current source, a toroid switch with contacts, through which the power source is connected to the corresponding pins of the stator and

0 rotary windings of electric motor G: -.

A disadvantage of this device is the lack of a shaft speed control. In this connection, non-causal5 can accurately determine the time when the direct current source is connected to the stator and rotor windings for braking, which, in turn, leads to large losses and additional heating, i.e. to reduce the reliability of the pump unit.

The purpose of the invention is to improve the reliability of the pump unit by increasing the accuracy of determining the moment of application of direct current to the stator and rotor windings of an electric motor.

This goal is achieved in that a device for automatically holding the shaft of a pumping unit containing an AC motor, a nycrta switch, contacts of which are included in the stator winding phases of an electric motor, are continuously connected by a button and a Start button, shunted by the closing switch of the start switch, DC source , the brake switch, the contacts of which are included in the two phases of the stator winding of the electric motor, has been introduced a time relay with two closing contacts with a delay time to turn off, a contactor with two closing contacts, an intermediate relay with two closing contacts, a frequency speed sensor with a measuring winding and an excitation winding, the outputs of which are connected via the first short circuit to a DC source, a circuit made up of coils connected in series inductance, capacitance and coil of overcurrent relay, equipped with a closing contact, and connected in series to the measuring winding of the frequency speed sensor, off the start switch is equipped with additional closing and opening contacts, and the brake switch. - the opening contact connected between the Stop button and one output of the start switch, the other output of which is connected to the first output terminal of the relay coil, the second output of which through one additional closing contact of the switch start-up Connected to the Stop button, one output of the contactor coil, one output of the time relay, one output of the intermediate relay, and one output of the coil of the brake switch through an additional release The contact of the switch, the start, is connected to one of the terminals of the direct current source, and through the second closing contact of the contactor. - with the first output of the rotor winding of an electric motor, the second output of which is connected with the coil of the brake inhibitor, another clamp of the direct current source is connected to the second output of the coil of the braking switch through the first closing contact of the contactor and the first closing contact of the voltage relay - to another output of the coil rel time, and closing contacts, time relay and overcurrent relay, shunted by the second contact of the intermediate relay, - to the other output of the intermediate relay cat. FIG. 1 is a schematic electrical diagram of devices for automatically holding a shaft on a pump assembly; in fig. . - electrically, the scheme of the frequency speed sensor; in fig. 3 -. speed sensor rotor design. The device for automatically holding the shaft of the pump unit contains an AC electric motor, for example, synchronous, with 1 stator and rotor 2 windings, a start switch 3.1 with closing contacts 3.2-3.6 and opening contact 3.7. closing contacts 3.2, 3.3, 3. of which are included in the phases of the stator winding 1 of a synchronous electric motor connected in series with the Stop button, Start button 5, shucked by the closing contact 3.5 of the start switch; breaker switch 6.1 with closing contacts 6.2, 6.3 and opening contact 6.Y, closing contacts 6.2, 6.3 of which are included in two phases of the stator winding of the electric motor, DC source 7, relay 8 ± 1 time with two closing contacts 8.7. and 8J3 (Fig. | with time delay for disconnection, contactor with coil 9.1 and two closing contacts 9.2 and 9i3, voltage relay 10.1 with closing contact 10.2 and intermediate relay t1.1 with two closing contacts 11.2 / IZ. A synchronous electric motor shaft 12 mechanically couples the frequency speed sensor 13. d .. The frequency speed sensor contains a C-shaped magnetic circuit C, on which the excitation winding 15 is located, connected via a closing contact 8.3 of the time relay to the direct current source 7, and the measuring winding 16, follower but with which is connected a circuit consisting of an inductance cat 17, a capacitor 18 and a coil 13.1 of the overcurrent relay (Fig. 2 I, equipped with a contact 19.2 for forming a resonant circuit. The rotor of the frequency speed sensor is a ring composed of alternating sectors magnetic 20 and insulating materials 21, which is mounted on the shaft 12 of an electric motor (Fig. 3). The start switch is additionally equipped with a closing 3. 6 and an interrupting 3.7 contact, and the brake switch with a disconnecting contact ft.k for prison between U Stop button and one terminal of the start switch 5, the other terminal of which is connected to a first terminal of the relay coil voltage etc. 10.1 n second relay output 10.1 via an additional voltage zamykattsy pin 3 'start switch 6 is connected to a stop button. One output of the time relay 8.1 coil, the contactor coil 9.1, the intermediate relay 11.1 and the braking on / off switch coil 6.1 through the additional resetting contact 3.7 off the start switch is connected to one of the terminals of the DC source 7, and through the second closing contact 9.3 of the contactor to one the output of the rotor "0th winding of the electric motor. Another terminal of the direct current source 7 is connected to the second coil output of the brake switch through the first closing contact 9.2 of the contactor 9.1 and through the first closing contact 10.2 of the voltage relay to another output of the time relay 8.1 coil, and through the closing contact 8.2 of the time relay and closing contact 19.2 of the relay overcurrent to another output of the coil of the intermediate relay, and the closing contact of the overcurrent relay is shunted by the closing contact P. of the intermediate relay. The device can be equipped with a battery areey 22, which is used as a backup power and is energized from the source 7 through a DC rectifier 23. The apparatus operates as follows. In the normal state, the start switch 3.1 is disconnected from the mains, and the synchronous motor of the pump unit does not work, the deceleration switch 6.1 and the contactor coil 9.1 are disconnected. When you press the 5 Start button, the start switch 3.1 is powered. The start switch is activated and connected with disconnecting contacts 3.2, 3.3, 3. synchronous motor

To the mains, the tripping contact 3.7 is simultaneously triggered in the braking switch circuit, the closing contact 3.5, locking the Start button 5, and the closing contact 3.6. Relay 10.1 55 The voltage is activated and closes the contact 10.2 in the coil circuit of the time relay 8.1.

the direct current in the stator winding 1 and the rotor winding 2 keeps the motor shaft stationary.

After the time required for the discharge of the discharge pipeline has expired, the time relay opens the contact 8.3 for the winding circuit 15 and excites61 When the Stop button is pressed or the power supply voltage fails, the start switch 3.1 is de-energized and the electric motor is disconnected, the contacts 3.2 and 3.3 are simultaneously disconnected and 3.6 are disconnected and closes by contact 3.7, connecting the coil 5 of the time relay 8.1 to the power source. The time relay is activated and closes, by contact 8.3, the circuit of the excitation winding 15 of the speed sensor, and by contact 8.2 - the coil circuit of the intermediate relay 11.1. After the holding time has elapsed, the contact 10o2 of the voltage relay turns off the coil of the time relay 8.1. I., "Under the action of the potential moment in the pressure pipe, the speed of rotation of the shaft of the synchronous motor and the ring of the frequency speed sensor approaches zero. Slowing the speed of rotation of the ring leads to a decrease in the frequency of intersection of the air gap of the magnetic circuit H by sectors of magnetic 20 and insulating 21 materials. The frequency of the induced EMF in the coil 16 varies in proportion to the frequency of rotation of the ring. At about zero speed of rotation of the ring, a series resonant circuit from the coil 19.1 of the overcurrent relay, the capacitor G8, and the coil 17 of the inductance enters into resonance. In this case, the overcurrent relay operates and its contact 19.2 connects the coil 11 of the intermediate relay. Intermediate relay 11.1 shunts its contact 11.2 contact 19.2, and contact 11.2 connects the coil 9.1 of the contactor ,, The contactor operates and closes contact 9.2 of the braking switch 6.1 The braking switch operates and opens the contact 6 .. Contacts 6.2, 6.3 of the braking switch and contact 9.3 of the contactor are connected in series with the stator the winding 1 and the rotor winding 2 to the parallel-connected rectifier 23 and the battery 22. In this case, the electromagnetic moment caused

The Research Institute of the frequency speed sensor, and the contact 8.2 - the coil circuit of the intermediate relay 11.1, the intermediate relay bypass the contact 11.2. Contact 19.2, and contact 11.3 - the circuit of Katuiaki 9.1 contactor. The contactor contact 9.2 opens the braking circuit 6.1. The contacts 9.3 of the contactor and the contacts 6.2, 6.3 of the braking switch 6.1 open the stator winding 1 and the rotor winding 2, and the contact 6. of the braking switch 6.1 closes the circuit of the start switch 3.1. The circuit is reset.

In the example of a specific embodiment of the device, a synchronous motor is adopted as the driving motor. The device is also applicable to pumping units with asyn Hron electric motors with a phase rotor.

The use of the proposed device eliminates the reverse rotation of the shaft of the pump unit and leads to a decrease in capital costs for the manufacture of an electric motor, to a decrease in the number of revisions of the unit and to increase the reliability of pump stations.

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Claims (1)

A DEVICE FOR AUTOMATICALLY HOLDING THE PUMP UNIT SHAFT, containing an alternating current motor, a start switch, the contacts of which are included in the phases of the stator winding of the electric motor, the Stop button and the Start button ¹¹ connected in series with the make contact of the start switch, a DC source, a brake switch, whose contacts are turned on in two phases of the stator winding of the electric motor, characterized in that, in order to increase the reliability of the pump unit by increasing the accuracy To determine the moment of direct current supply to the stator and rotor windings of the electric motor, a time relay with two make contacts with a delay time for switching off, a contactor with two make contacts, an intermediate relay with two make contacts, a frequency speed sensor with a measuring winding and a field winding are introduced into it the conclusions of which are connected through the first closing contact of the time relay to a constant current source, a circuit composed of series-connected inductors, capacitor spine and overcurrent relay coil provided with a closing contact, and connected in series to the measuring frequency winding speed sensor, additional start switch is provided with a make and break contacts, a brake switch - break contact connected between _about knop- Coy Stop and one terminal of the start switch the other terminal of which is connected to the first terminal of the voltage relay coil, the second terminal of which, through one additional make contact of the start switch, is connected to the button Sto n, one terminal output of the contactor coil, one terminal of the time relay, one terminal of the intermediate relay and one terminal of the coil of the brake switch through an additional opening contact of the start switch is connected to one of the terminals of the DC source, and through the second terminal of the contactor with the first terminal of the rotor motor winding, the second terminal of which is connected to the coil of the brake switch, the other terminal of the DC source is connected to the second terminal of the coil of the brake switch through the first make contact t con. , a clock and through the first make-up · contact of the voltage relay to the other output of the coil of the time relay, and the make-up contacts, the time relay and to .1029364 le of the maximum current shunted by le, to the other output of the coil pro, the second contact of the intermediate intermediate relay.