CN210405129U - Motor starting device - Google Patents
Motor starting device Download PDFInfo
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- CN210405129U CN210405129U CN201921652299.3U CN201921652299U CN210405129U CN 210405129 U CN210405129 U CN 210405129U CN 201921652299 U CN201921652299 U CN 201921652299U CN 210405129 U CN210405129 U CN 210405129U
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Abstract
The utility model relates to the field of motor control, in particular to a motor starting device, which comprises a power loop and a control loop, wherein the power loop is provided with a power switch, a first relay, a first current transformer, a second relay, a first contactor, a second contactor, a third contactor, a fourth contactor, a first motor and a first resistor; the motor starting method has the advantages that the short circuit phenomenon and the phenomenon that harmonic waves pollute the power grid when the motor is switched in the starting mode are avoided, the generated secondary peak current and the impact on the power grid are reduced, the impact of the starting current on the electric elements in the power grid in the starting process of the motor can be effectively reduced, the service life of the electric elements is prolonged, the early-stage investment and later-stage maintenance cost is reduced, the operation steps are simplified, and the use efficiency is improved.
Description
Technical Field
The utility model relates to a motor control field, in particular to motor starting device.
Background
The compressor can be used in the fields of ultra-low temperature refrigeration, food quick freezing, low temperature refrigeration, chemical pharmacy, ice cold accumulation, refrigerant water, concrete cooling, process refrigerant water, ship refrigeration and the like. The power of the motor is from several kilowatts to several kilowatts, and even larger; the common starting mode of the motor at present comprises the following steps: starting a frequency converter, starting a soft starter, starting a self-coupling voltage reduction, starting a star triangle and the like; the problems that the price is high, the system parameter setting is complex, the generated harmonic pollutes the power grid, and the potential safety hazard is caused to the normal use of the power grid and other electric equipment in the power grid exist in the starting of the frequency converter and the soft starter; the self-coupling voltage reduction starting has the problems that in the process of converting voltage reduction to full voltage, a voltage reduction contactor is disconnected, the current of a motor can be completely interrupted and the rotating speed is reduced in the time period when the full voltage contactor is not attracted, when an angle-shaped contactor is connected, the phase of a power grid is possibly opposite to the magnetic field of the motor, a very high conversion current peak value can be caused in the transient process, even the contact of the contactor is subjected to fusion welding, finally a protection mechanism acts, and the motor cannot be started; the star-delta starting has the problems that in the star-delta switching process, a star contactor is disconnected, the motor current can be completely interrupted and the rotating speed is reduced in the time period that an angle contactor is not attracted, when the angle contactor is switched on, the phase of a power grid is possibly opposite to the magnetic field of the motor, a very high switching current peak value can be caused in the transient process, even the contactor contact is subjected to fusion welding, the final protection mechanism acts, and the motor cannot be started.
SUMMERY OF THE UTILITY MODEL
Technical problem to be solved
In order to solve the above-mentioned problem of the prior art, the utility model provides a reduce motor starting current by a wide margin and reduce motor starting current to the motor starting device of the impact of electric wire netting.
(II) technical scheme
In order to achieve the above object, the utility model discloses a main technical scheme include:
a motor starting device comprises a power loop and a control loop, wherein a power switch, a first relay, a first current transformer, a second relay, a first contactor, a second contactor, a third contactor, a fourth contactor, a first motor and a first resistor are arranged on the power loop; one end of the power switch is electrically connected with a first current transformer and a first contactor, the first current transformer is electrically connected with a second relay, the first relay is respectively electrically connected with one end of the first contactor, one end of a second contactor and one end of a first resistor, the other end of the first contactor is electrically connected with a first motor, the other end of the second contactor is electrically connected with a first motor, the other end of the first resistor is electrically connected with one end of a fourth contactor, and the other end of the fourth contactor is respectively electrically connected with the first motor and a third contactor; the control circuit is provided with a first fuse, a first switch, a third contactor switch, a first contactor switch, a second contactor normally closed switch, a first time relay, a second contactor switch, a fourth contactor normally closed switch, a third contactor normally closed switch, a first time relay coil and a second time relay coil, one end of the first fuse is electrically connected with one end of the first switch, the other end of the first switch is respectively electrically connected with one end of the third contactor switch, one end of the first contactor switch, one end of the second contactor normally closed switch, one end of the second time relay and one end of the second contactor switch, the other end of the third contactor switch is electrically connected with the first contactor, the other end of the first contactor switch is electrically connected with the first contactor, the other end of the second contactor normally closed switch is respectively and electrically connected with one end of the first time relay, the coil of the first time relay, one end of the first contactor normally closed switch is electrically connected, the other end of the first time relay is electrically connected with a second time relay coil and a fourth contactor, the other end of the fourth contactor normally closed switch is electrically connected with the third contactor, the other end of the second time relay is electrically connected with the third contactor normally closed switch, the other end of the second contactor switch is electrically connected with a third contactor normally closed switch which is electrically connected with the second contactor, the other end of the first contactor, the other end of the second time relay coil, the other end of the fourth contactor, the other end of the first time relay coil, the other end of the third contactor and the other end of the second contactor are electrically connected with each other.
The motor starting device comprises a current detection device, and the current detection device is electrically connected with the second relay.
In the above motor starting device, the first relay is a phase sequence relay, and the second relay is a thermal overload relay.
In the above motor starting device, the signal terminal is electrically connected to the second relay.
In the above motor starting device, the rated voltage of the first motor is not more than 690V, and the rated power is not less than 55 KW.
In the above motor starting device, the first resistor is a ripple resistor.
In the above motor starting device, the first switch adopts an intermediate relay contact structure.
In the above-mentioned motor starting apparatus, the power switch is a main power switch.
(III) advantageous effects
The utility model has the advantages that: through setting up control circuit and power return circuit, set up a plurality of contactors in power return circuit, first current transformer, first resistance, first relay and second relay, be favorable to avoiding the motor to appear the short circuit phenomenon when the start mode switches over and produce the phenomenon that the harmonic pollutes the electric wire netting, reduce the secondary spike current that produces simultaneously and the impact to the electric wire netting, can effectively alleviate the impact of starting current to the electric element in the electric wire netting among the motor start-up process, increase electric element's life, reduce the cost of input and later maintenance in earlier stage, simplify the operation steps, and the service efficiency is improved.
Drawings
Fig. 1 is a schematic structural diagram of a power circuit of the motor starting device of the present invention;
fig. 2 is a schematic structural diagram of a control circuit of the motor starting device of the present invention;
fig. 3 is a schematic control logic diagram of the motor starting apparatus of the present invention.
[ description of reference ]
1: a power circuit;
2: a control loop;
3: a power switch;
4: a first relay;
5: a first current transformer;
6: a second relay;
7: a first contactor;
8: a second contactor;
9: a third contactor;
10: a fourth contactor;
11: a first motor;
12: a first resistor;
13: a first fuse;
14: a first switch;
15: a third contactor switch;
16: a first contactor switch;
17: a second contactor normally closed switch;
18: a first time relay;
19: a second time relay;
20: a second contactor switch;
21: a fourth contactor normally closed switch;
22: a third contactor normally closed switch;
23: a first time relay coil;
24: a second time relay coil.
Detailed Description
For better explanation, the present invention is described in detail with reference to the accompanying drawings in order to facilitate understanding.
The utility model discloses the most crucial design lies in: through setting up power circuit and control circuit, set up a plurality of contactors, first resistance, first current transformer, first relay and second relay on power circuit, set up first time relay and second time relay on control circuit.
Referring to fig. 1 to 3, a motor starting apparatus,
the power circuit is provided with a power switch, a first relay, a first current transformer, a second relay, a first contactor, a second contactor, a third contactor, a fourth contactor, a first motor and a first resistor; one end of the power switch is electrically connected with a first current transformer and a first contactor, the first current transformer is electrically connected with a second relay, the first relay is respectively electrically connected with one end of the first contactor, one end of a second contactor and one end of a first resistor, the other end of the first contactor is electrically connected with a first motor, the other end of the second contactor is electrically connected with a first motor, the other end of the first resistor is electrically connected with one end of a fourth contactor, and the other end of the fourth contactor is respectively electrically connected with the first motor and a third contactor; the control circuit is provided with a first fuse, a first switch, a third contactor switch, a first contactor switch, a second contactor normally closed switch, a first time relay, a second contactor switch, a fourth contactor normally closed switch, a third contactor normally closed switch, a first time relay coil and a second time relay coil, one end of the first fuse is electrically connected with one end of the first switch, the other end of the first switch is respectively electrically connected with one end of the third contactor switch, one end of the first contactor switch, one end of the second contactor normally closed switch, one end of the second time relay and one end of the second contactor switch, the other end of the third contactor switch is electrically connected with the first contactor, the other end of the first contactor switch is electrically connected with the first contactor, the other end of the second contactor normally closed switch is respectively and electrically connected with one end of the first time relay, the coil of the first time relay, one end of the first contactor normally closed switch is electrically connected, the other end of the first time relay is electrically connected with a second time relay coil and a fourth contactor, the other end of the fourth contactor normally closed switch is electrically connected with the third contactor, the other end of the second time relay is electrically connected with the third contactor normally closed switch, the other end of the second contactor switch is electrically connected with a third contactor normally closed switch which is electrically connected with the second contactor, the other end of the first contactor, the other end of the second time relay coil, the other end of the fourth contactor, the other end of the first time relay coil, the other end of the third contactor and the other end of the second contactor are electrically connected with each other.
Motor starting drive's theory of operation: after a first switch is firstly closed, a first contactor, a third contactor and a first time relay coil are powered on, a motor starts to operate in a star shape, after a first period of time is timed, the first time relay starts to work, a fourth contactor and a second time relay are powered on, the third contactor is powered off, after a second period of time is timed, the third contactor is completely disconnected, the second time relay acts, the first contactor and the second contactor are powered on, the third contactor, the fourth contactor, the first time relay and the second time relay are powered off, the motor operates in a full-voltage mode, and the motor is started to be completed.
From the above description, the beneficial effects of the present invention are: through setting up control circuit and power return circuit, set up a plurality of contactors in power return circuit, first current transformer, first resistance, first relay and second relay, be favorable to avoiding the motor to appear the short circuit phenomenon when the start mode switches over and produce the phenomenon that the harmonic pollutes the electric wire netting, reduce the secondary spike current that produces simultaneously and the impact to the electric wire netting, can effectively alleviate the impact of starting current to the electric element in the electric wire netting among the motor start-up process, increase electric element's life, reduce the cost of input and later maintenance in earlier stage, simplify the operation steps, and the service efficiency is improved.
Further, the device comprises a current detection device, and the current detection device is electrically connected with the second relay.
As can be seen from the above description, by including the current detection device electrically connected to the second relay, it is advantageous to detect the current when the motor operates, and to improve the reliability of the device.
Further, the first relay adopts a phase sequence relay, and the second relay adopts a thermal overload relay.
It can be known from the above description that, adopt the phase sequence relay through first relay, the second relay adopts thermal overload relay, is favorable to detecting whether the power has unusually, meets unusual circumstances and in time switches over the power, improves the security of device.
Further, the signal terminal is electrically connected with the second relay.
As can be seen from the above description, by including the signal terminal electrically connected to the second relay, it is advantageous to improve the efficiency of signal transmission.
Further, the rated voltage of the first motor is not more than 690V, and the rated power is not less than 55 KW.
From the above description, it can be known that the rated voltage of the first motor is not more than 690V, and the rated power is not less than 55KW, which is beneficial to further improve the safety of the device.
Further, the first resistor is a ripple resistor.
It can be known from the above description that the first resistor is a corrugated resistor, which is beneficial to keeping the motor in a power-on state all the time in the starting process and avoiding the influence of the power-off of the motor on the use efficiency.
Further, the first switch adopts an intermediate relay contact structure.
As can be seen from the above description, the efficiency of starting is advantageously improved by adopting the intermediate relay contact structure for the first switch.
Further, the power switch is a main power switch.
As can be seen from the above description, by setting the power switch as the master power switch, it is beneficial to uniformly control the power of the device circuit, and the safety of the device is further improved.
Referring to fig. 1 to fig. 3, a first embodiment of the present invention is:
a motor starting device comprises a power circuit 1 and a control circuit 2, wherein a power switch 3, a first relay 4, a first current transformer 5, a second relay 6, a first contactor 7, a second contactor 8, a third contactor 9, a fourth contactor 10, a first motor 11 and a first resistor 12 are arranged on the power circuit 1; one end of the power switch 3 is electrically connected with a first current transformer 5 and a first contactor 7, the first current transformer 5 is electrically connected with a second relay 6, the first relay 4 is respectively electrically connected with one end of the first contactor 7, one end of a second contactor 8 and one end of a first resistor 12, the other end of the first contactor 7 is electrically connected with a first motor 11, the other end of the second contactor 8 is electrically connected with the first motor 11, the other end of the first resistor 12 is electrically connected with one end of a fourth contactor 10, and the other end of the fourth contactor 10 is respectively electrically connected with the first motor 11 and a third contactor 9; the control circuit 2 is provided with a first fuse 13, a first switch 14, a third contactor switch 15, a first contactor switch 16, a second contactor normally-closed switch 17, a first time relay 18, a second time relay 19, a second contactor 8 switch, a fourth contactor normally-closed switch 21, a third contactor normally-closed switch 22, a first time relay coil 23 and a second time relay coil 24, one end of the first fuse 13 is electrically connected with one end of the first switch 14, the other end of the first switch 14 is respectively electrically connected with one end of the third contactor switch 15, one end of the first contactor switch 16 is electrically connected, one end of the second contactor normally-closed switch 17 is electrically connected, one end of the second time relay 19 is electrically connected and one end of the second contactor switch 20 is electrically connected, the other end of the third contactor switch 15 is electrically connected with the first contactor 7, the other end of first contactor switch 16 is connected with first contactor 7 electricity, the other end of second contactor normally closed switch 17 is connected with the one end electricity of first time relay 18 respectively, first time relay coil 23 electricity is connected, and the one end electricity of first contactor normally closed switch is connected, the other end of first time relay 18 is connected with second time relay coil 24 electricity and fourth contactor 10 electricity is connected, fourth contactor normally closed switch 21's the other end is connected with third contactor 9 electricity, the other end of second time relay 19 is connected with third contactor normally closed switch 22 electricity, the other end of second contactor switch 20 is connected with third contactor normally closed switch 22 electricity, third contactor normally closed switch 22 is connected with second contactor 8 electricity, the other end of first contactor 7, the other end of second time relay coil 24, another end, The other end of the fourth contactor 10, the other end of the first time relay coil 23, the other end of the third contactor 9, and the other end of the second contactor 8 are electrically connected to each other.
A current detection device is included, which is electrically connected to the second relay 6.
The first relay 4 is a phase sequence relay, and the second relay 6 is a thermal overload relay.
Comprising a signal terminal, which is electrically connected to the second relay 6.
The rated voltage of the first motor 11 is not more than 690V, and the rated power is not less than 55 KW.
The first resistor 12 is a ripple resistor.
The first switch 14 adopts an intermediate relay contact structure.
The power switch 3 is a main power switch 3.
The control loop and the power loop can share one power supply or are respectively provided with two independent power supplies for supplying power, one end of the power supply of the control loop is electrically connected with the first fuse, the other end of the power supply of the control loop is electrically connected with the other end of the first contactor 7, the other end of the second time relay coil 24, the other end of the fourth contactor 10, the other end of the first time relay coil 23, the other end of the third contactor 9 and the other end of the second contactor 8 respectively, the power supply is directly and electrically connected with a power switch on the power loop, the power switch 3 is a main power switch 3, the first relay 4 is a phase sequence relay and is used for monitoring whether the power supply is in phase failure, reverse phase, undervoltage and overvoltage or not, if the power supply is abnormal, an abnormal signal is transmitted to the control loop 2 to cut off the; the first current transformer 5 is a current transformer and used for measuring the running current of the motor, and is matched with the second relay 6 which is a thermal overload relay for use, so that an overload signal can be output to the control loop 2 when the motor is overloaded, the power supply of the motor is cut off, and the equipment is prevented from being damaged; the signal terminal is connected with a current signal output by the secondary side of the mutual inductor and can be connected with a transmitter and a controller through the terminal to display current and participate in equipment control; the first contactor 7 and the second contactor 8 are used for full-voltage operation of the motor, the third contactor 9 and the fourth contactor 10 are used in the starting process of the motor, the first resistor 12 is a transition resistor, and a corrugated resistor can be used for keeping the motor in a power-on state all the time in the starting process of the motor; the first switch 14 is a control signal for starting the motor, and may be a button, a knob, an intermediate relay contact, a manual control, or a controller control.
Referring to fig. 1 to fig. 3, a second embodiment of the present invention is:
an operation timing diagram of a motor starting device is shown in fig. 3, wherein 1KC1 is a first switch 14, 1KM1 is a first contactor 7, 1KM2 is a second contactor 8, 1KM3 is a third contactor 9, 1KM4 is a fourth contactor 10, 1KT1 is a first time relay 18, 1KT2 is a second time relay 19, TI is a first time relay timing time, T2 is a second time relay timing time, and T3 is a third time relay timing time.
The start-up procedure can be divided into 3 phases:
a. starting: after the 1KC1 is closed, the coils of 1KM1, 1KM3 and 1KT1 are electrified, the motor operates in a star shape, and the 1KT1 starts timing (T1);
b. putting the resistor into operation: after the time of T1, the 1KT1 contact is closed (ON), the coils of the 1KM4 and the 1KT2 are electrified, in the stage, the 1KM1 and the 1KM4 contact are closed and electrified (ON), the 1KM3 contact is immediately Opened (OFF) after the 1KM4 contact is closed, and the 1KT2 starts to time (T2);
c. and (3) stopping the operation of the resistor: after the time of T2, 1KM3 is completely disconnected, 1KT2 contacts are closed (ON) to cut off the power supply of the coil of 1KM4, and in the phase, 1KM1 and 1KM2 contacts are closed and electrified (ON), the coils of 1KM3, 1KM4, 1KT1 and 1KT2 are powered off, the motor runs in full voltage, and the starting is completed.
Description of the starting procedure:
a, T1: the star-shaped running time of the motor;
and b, T2: the resistance input time is longer than the time for releasing the contact of 1KM 3;
c. since the 1KM4 loop has a resistor as a load, the short circuit is not caused by turning on 1KM4 and then turning off 1KM 3.
To sum up, the utility model provides a pair of motor starting device, through setting up control circuit and power return circuit, set up a plurality of contactors in power return circuit, first current transformer, first resistance, first relay and second relay, be favorable to avoiding the motor short circuit phenomenon to appear and produce the phenomenon that the harmonic pollutes the electric wire netting when the start mode switches, reduce the secondary peak current that produces simultaneously and the impact to the electric wire netting, can effectively alleviate the impact of starting current to the electric elements in the electric wire netting among the motor starting process, increase electric elements's life, reduce the cost that drops into in earlier stage and later maintenance, simplify the operation step, and the service efficiency is improved.
The above mentioned is only the embodiment of the present invention, and not the limitation of the patent scope of the present invention, all the equivalent transformations made by the contents of the specification and the drawings, or the direct or indirect application in the related technical field, are included in the patent protection scope of the present invention.
Claims (8)
1. A motor starting device is characterized by comprising a power loop and a control loop, wherein the power loop is provided with a power switch, a first relay, a first current transformer, a second relay, a first contactor, a second contactor, a third contactor, a fourth contactor, a first motor and a first resistor; one end of the power switch is electrically connected with a first current transformer and a first contactor, the first current transformer is electrically connected with a second relay, the first relay is respectively electrically connected with one end of the first contactor, one end of a second contactor and one end of a first resistor, the other end of the first contactor is electrically connected with a first motor, the other end of the second contactor is electrically connected with a first motor, the other end of the first resistor is electrically connected with one end of a fourth contactor, and the other end of the fourth contactor is respectively electrically connected with the first motor and a third contactor; the control circuit is provided with a first fuse, a first switch, a third contactor switch, a first contactor switch, a second contactor normally closed switch, a first time relay, a second contactor switch, a fourth contactor normally closed switch, a third contactor normally closed switch, a first time relay coil and a second time relay coil, one end of the first fuse is electrically connected with one end of the first switch, the other end of the first switch is respectively electrically connected with one end of the third contactor switch, one end of the first contactor switch, one end of the second contactor normally closed switch, one end of the second time relay and one end of the second contactor switch, the other end of the third contactor switch is electrically connected with the first contactor, the other end of the first contactor switch is electrically connected with the first contactor, the other end of the second contactor normally closed switch is respectively and electrically connected with one end of the first time relay, the coil of the first time relay, one end of the first contactor normally closed switch is electrically connected, the other end of the first time relay is electrically connected with a second time relay coil and a fourth contactor, the other end of the fourth contactor normally closed switch is electrically connected with the third contactor, the other end of the second time relay is electrically connected with the third contactor normally closed switch, the other end of the second contactor switch is electrically connected with a third contactor normally closed switch which is electrically connected with the second contactor, the other end of the first contactor, the other end of the second time relay coil, the other end of the fourth contactor, the other end of the first time relay coil, the other end of the third contactor and the other end of the second contactor are electrically connected with each other.
2. The motor starting device of claim 1 including a current sensing device electrically connected to the second relay.
3. The motor starting device according to claim 1, wherein the first relay is a phase sequence relay, and the second relay is a thermal overload relay.
4. The motor starting device of claim 1 including signal terminals electrically connected to the second relay.
5. The motor starting device according to claim 1, wherein a rated voltage of said first motor is not more than 690V, and a rated power is not less than 55 KW.
6. The motor starting device of claim 1 wherein said first resistor is a ripple resistor.
7. The motor starting device of claim 1 wherein said first switch is in the configuration of an intermediate relay contact.
8. The motor starting device of claim 1 wherein said power switch is a mains power switch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921652299.3U CN210405129U (en) | 2019-09-30 | 2019-09-30 | Motor starting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921652299.3U CN210405129U (en) | 2019-09-30 | 2019-09-30 | Motor starting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210405129U true CN210405129U (en) | 2020-04-24 |
Family
ID=70343533
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921652299.3U Active CN210405129U (en) | 2019-09-30 | 2019-09-30 | Motor starting device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210405129U (en) |
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2019
- 2019-09-30 CN CN201921652299.3U patent/CN210405129U/en active Active
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