CN2164613Y - Mixed voltage-regulating starting controller for ac motor - Google Patents
Mixed voltage-regulating starting controller for ac motor Download PDFInfo
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- CN2164613Y CN2164613Y CN 93239269 CN93239269U CN2164613Y CN 2164613 Y CN2164613 Y CN 2164613Y CN 93239269 CN93239269 CN 93239269 CN 93239269 U CN93239269 U CN 93239269U CN 2164613 Y CN2164613 Y CN 2164613Y
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- contactor
- autotransformer
- motor
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- 230000005611 electricity Effects 0.000 claims description 16
- 238000000034 method Methods 0.000 abstract description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 12
- 238000005516 engineering process Methods 0.000 description 9
- 238000004804 winding Methods 0.000 description 9
- 230000000694 effects Effects 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 239000012467 final product Substances 0.000 description 3
- 230000007812 deficiency Effects 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000976 Electrical steel Inorganic materials 0.000 description 1
- 241000406668 Loxodonta cyclotis Species 0.000 description 1
- 241000209140 Triticum Species 0.000 description 1
- 235000021307 Triticum Nutrition 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000003306 harvesting Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Abstract
The mixed voltage regulation of AC motor starts controlling means has solved the great problem of power voltage drop when AC motor starts, the utility model discloses change the autotransformer who is equipped with a star hookup point into the autotransformer who has a plurality of star hookup points, at the power head end of this transformer to the coil section between the first star hookup point, be equipped with the special hookup motor of a plurality of confessions selection take a percentage to at a contactor of its every star hookup point hookup, this transformer contactor, motor, three phase current etc. constitute the main circuit, at three phase current's arbitrary double-phase hookup control circuit. The device can start by multi-stage voltage regulation, reduces the number of autotransformer coils, and has simple iron core structure and process.
Description
The utility model is an alternating current motor combined voltage regulation start-control device.
Know according to the retrieval, by the successful variable voltage starter controller of Japanese electric light company research (see " low voltage electrical apparatus technology information " 1981 third phase the 12nd page) is to add at first that in the moment of starting motor a low-voltage (50% rated voltage) delayed time through 0.5～1 second, transfer the starting of 70% rated voltage to, when rotating speed rises near rated value, transfer the direct-on-line starting operation to, reach three grades of auto-induction voltage-reduced startings.There is following deficiency in this controller: the one, can only three grades of startings, and the 2nd, the autotransformer coil number is more, (eight of three-phases), the core structure complexity, complex process, the 3rd, during the low pressure starting, no matter the size of the quiet resistive torque of dragging system, be 50% rated voltage starting entirely, when the quiet resistive torque of dragging system is bigger, motor can not change when low pressure is started, and the time in the starting of 50% rated voltage can not be regulated, no matter the capacity motor size, heavy duty, underloading or no-load starting all are 0.5～1 second.
The purpose of this utility model is the deficiency at above-mentioned prior art, develops a kind of alternating current motor combined voltage regulation start-control device.This device can reach the multi-stage pressure regulating starting, reduce the autotransformer coil number, core structure and technology are simple, during electric motor starting, the user is according to the size of the quiet resistive torque of dragging system, change and drag the size that is added on the motor terminal starting voltage, can specifically regulate the time of each step voltage effect according to different load characteristics.
To achieve these goals, the utility model adopts following technical proposals:
With traditional autotransformer reconfiguration that only is provided with a star interface is the autotransformer with n star interface, and n is arbitrary positive integer in 2 to 10.The power supply head end of autotransformer to coil segment between first star interface is provided with the tap of m selective special connection motor, and m is arbitrary positive integer of 1 to 10.In starting process, the autotransformer end that is connected to power supply is constant, the tap of autotransformer that is connected to motor is constant, by the automatic different star interface of the short circuit turn ratio of regulating autotransformer respectively, and then adjusting puts on the terminal voltage of motor terminal, and from star interface of short circuit to the process of another star interface of short circuit, asterism standard-sized sheet road, autotransformer uses as solid reactor, like this, autotransformer and reactor mixed and alternate move, and reach the purpose of multistage step-down.Its starting progression is the starting of n+1 level, and the contactor number of using is n+2.Less when the moment of inertia of motor driving system, quiet resistive torque hour can each be connected to the lower tap of voltage in the autotransformer m tap mutually with motor, makes the voltage drop of motor starting moment must be lower, and starting current is less; When the moment of inertia of dragging system is bigger, when quiet resistive torque is big, motor can be connected to the higher tap of voltage in the autotransformer m tap, make the starting torque of motor bigger, to satisfy of the requirement of the quiet resistive torque of dragging system to starting torque.
The main circuit of this device is: three phase mains is connected to operation three-phase contactor K
CLThe upper end, be terminated at threephase motor under it.Rise and employ three-phase contactor K
1On be terminated at three phase mains, what it was terminated at down 3-phase autotransformer connects power end (head end).Each corresponding connection of lower end of the three-phase contactor that in each phase m tap of 3-phase autotransformer any one and the three phase mains end of alternating current machine connect.The tap of the star interface of 3-phase autotransformer n the corresponding turn ratio respectively is connected to an end of the three-phase contactor of the required turn ratio asterism of short circuit, and its other end respectively is connected into short circuit.Like this, the first, closed near that star interface contactor K that connects the motor tap
2Second closed that contactor K that connects between autotransformer head end and power supply
1, motor is started in low pressure; The 3rd, disconnect the contactor of previous short circuit asterism, closed distal is from the asterism contactor that connects the motor tap, until disconnecting last asterism contactor, closed operation contactor disconnects that contactor that connects between autotransformer head end and power supply at last, and starting process finishes.
In control circuit, the contactor of a short circuit asterism of a time relay control, the length of the contactor closing time of some short circuit asterisms, (being that a certain voltage is in the motor side length of action time), control by its time relay of control, to satisfy the needs of different concrete conditions.
The control circuit structure of this device is: the first, and by the parallel connection of following n+1 bar electricity branch road: article one branch road is button S
2Normally open contact and contactor K
2often open the auxiliary contact parallel connection after, again with second asterism contactor of short circuit K
3Normally closed auxiliary contact, control K
2Time relay KT
1Normally closed time-delay breaking-off contact, contactor K
2Coil series connection; The second branch road is K
2often open auxiliary contact and K
1often open the auxiliary contact parallel connection after, again with K
1Coil, KT
1Coils from parallel connection of coils after circuit series connection; Since the 3rd circuit, total n-1 bar branch road, this n-1 bar branch road, be by an asterism contactor behind normally open contact and the short circuit of the time relay of the previous short circuit asterism contactor of control often open auxiliary contact in parallel after, again with after the coil of the normally closed time-delay breaking-off contact of the time relay of the normally closed auxiliary contact of the previous asterism contactor of control, the back asterism contactor of control, the back asterism contactor of control connect, connect with the circuit of the coils from parallel connection of coils of the time relay of controlling a back asterism contactor.After this n+1 bar branch road parallel connection, again with operation contactor K
CLThe series connection of normally closed auxiliary contact constitute article one electricity loop.The second, by the time relay of last asterism contactor of control often open time-delay close contact, first and the normally closed auxiliary contact series connection of last asterism contactor after, with operation contactor K
CLoften open the auxiliary contact parallel connection, again with operation contactor K
CLThe coil series connection constitutes second electricity loop.The 3rd, after these two electric loop parallel connections, again with button S
1Normally closed interlock series connection constitute electrical schematic diagram.Any two-phase that two of this control circuit schematic diagram is connected to three phase mains gets final product.
The technique effect of this control device owing to adopt the pressure regulation starting, so starting current can fall lowlyer, reduces degree on the starting transient voltage and decides.If starting moment motor terminal voltage is α with the ratio of rated voltage, starting current is i during the starting of alternating current motor rated voltage
StNAnd be motor rated current I
N7 times, then this starting device starting moment is to the impulse current i of electrical network
St=7I
Nα
2, when α=0.45, i
St=1.4I
NWhen α=0.5, i
St=1.75I
NOr the like.
This device is compared near technology with up-to-date, be three grades of startings near technology, and this device is multistage starting, starts more steady; Coil number near the technology three-phase is eight, and this device has only three, and coil is few, and technology is simply economized copper; Be " field " shape near the technology core structure, and this device be "
" shape, core structure is simple, and technology is simple, economizes silicon steel sheet; Must very short (0.5～1 second) in the low pressure starting time near technology, otherwise can burn autotransformer short-circuited coil in the starter, and there is not this problem in this device, and any one voltage that acts on motor side can specifically be regulated according to different load characteristics, reaches Optimal Control.
Use this device, for the alternating current motor that resembles no excitation---the dragging system that the DC generation unit is such, the time that then low pressure can be put on motor terminal increases relatively, and the time that middle pressure puts on motor terminal is shortened relatively, transfers the total head operation at last to.For resembling centrifugal water pump, the such dragging system of blower fan, the time that then low pressure can be put on motor terminal shortens relatively, and the time that middle pressure puts on motor terminal is increased relatively, transfers the total head operation at last to.Such heavy duty drags unit for elephant hide band transporter, the one, motor is connected to the high voltage tap of transformer, the 2nd, the time that low pressure is put on motor terminal shortens greatly, and the time that middle pressure puts on motor terminal is increased, and transfers the direct-on-line starting action at last to.
This combined voltage regulation start-control device is widely used in the electric drive systems such as industry, agricultural, national defence, particularly not enough for those industrial and mining enterprises' house generator capacity, the dragging unit, need to increase capacity motor of fail to start, but the electric power system that net capacity (prime transformer capacity) is not enough again, large-scale, medium-sized squirrel-cage motor drag unit and to the occasion that grid voltage quality is had relatively high expectations, the incomparable advantage of other starting and control equipment are arranged.
Described in detail below in conjunction with accompanying drawing.
Embodiment 1 is m=2, the combined voltage regulation start-control device of n=2.
Fig. 1 is m=2, and the 3-phase autotransformer winding of the combined voltage regulation start-control device of n=2 connects schematic diagram.
Fig. 2 is m=2, the combined voltage regulation start-control device main circuit schematic diagram of n=2.
Fig. 3 is m=2, the combined voltage regulation start-control device control circuit schematic diagram of n=2.
Fig. 4 is m=2, and the combined voltage regulation start-control device control system of n=2 connects circuit theory diagrams.
In Fig. 1, autotransformer is the autotransformer of three grades of startings, and its three-phase is respectively U phase, V phase, W phase.Connect power end (head end) and be respectively U
1, V
1, W
1, the tap of two selective connection three phase electric machines is respectively U
2, V
2, W
2, U
3, V
3, W
3, when the quiet resistive torque of dragging system hour, U
3, V
3, W
3Connect motor, when the quiet resistive torque of dragging system is big, U
2, V
2, W
2Connect motor.Two star interfaces are respectively U
4, V
4, W
4, U
5, V
5, W
5, work as U
5, V
5, W
5Open circuit, U
4, V
4, W
4When short circuit was a bit, U was worked as in the starting of motor low pressure
4, V
4, W
4Open circuit, U
5, V
5, W
5When short circuit was a bit, motor terminal voltage was heightened; Work as U
4, V
4, W
4, U
5, V
5, W
5Open circuit, U
1, V
1, W
1When connecing power supply, motor is a reactor starting.Work as U
4, V
4, W
4, U
5, V
5, W
5Open circuit, three of motor is connected to the power supply (K among Fig. 4
CLClosed circuit) time, motor transfers to direct-on-line starting.
The operation principle of Fig. 4 is as follows:
When pressing starting button S
2The time, contactor K
2Coil electricity, K
2The normally open contact closure, the asterism U of autotransformer
4, V
4, W
4Short circuit, K
2Normally closed interlock disconnect contactor K
1Coil, time relay KT
1The coil K that switches on simultaneously
1The normally open contact closure, normally closed interlock disconnects, alternating current motor starts under low-voltage.Through time relay KT
1After the time-delay, KT
1Normally closed time-delay breaking-off contact disconnect K
2Coil losing electricity, K
2Contact resets, the asterism U of autotransformer
4, V
4, W
4Open circuit, in this moment, autotransformer is for the first time as reactor operation, KT
1often open timing closing contact closure, contactor K
3Coil, time relay KT
2Coil is switched on simultaneously, contactor K
3The normally open contact closure, another asterism U of autotransformer
5, V
5, W
5Short circuit, this moment, autotransformer changed the turn ratio, heightened and had failed voltage, and alternating current motor starts in middle pressure.Again through time relay KT
2Time-delay, KT
2Normally closed time-delay contact disconnect K
3Coil losing electricity, K
3Reset another asterism U of autotransformer
5, V
5, W
5Open circuit, this moment, autotransformer used as reactor for the second time, KT
2The time-delay of often opening close contact closure, contactor K
CLCoil electricity, the normally open contact closure, normally closed interlock disconnects, KT
1, KT
2Coil losing electricity, motor is adjusted to the direct-on-line starting operation simultaneously.At last, K
1Disconnect, starting process finishes.
The m=2 that has developed, the combined voltage regulation start-control device of n=2 control 45KW motor, the U of autotransformer coil
1U
2One section is 50 circles, U
2U
3One section is 6 circles, U
3U
4One section is 56 circles, U
4U
5One section is 75 circles, and V is mutually identical with U with W mutually.Major loop and control loop principle are pressed Fig. 2, Fig. 3 and are connected, and motor is connected on U
3, V
3, W
3Tap.In major loop, work as K
1, K
2Terminal voltage of motor is when closed
* 100%=56/ (50+6+56) * 100%=50% supply voltage works as K
2Disconnect K
3When closed, terminal voltage of motor is transferred
* 100%=(56+75)/(50+6+56+75) * 100%=70% supply voltage.This combined voltage regulation start-control device is the industry trial run on the 40KWJ02 pump motor, and with ultraviolet oscilloscope starting voltage and starting current record ripple is tested the sensible ideal effect that arrived of table with test results.Be 1.85 times of motor rated current to the starting current of electrical network when low pressure is started, the starting time is 5.4 seconds, is 2.06 times of motor rated current to the starting current of electrical network when pressing starting in being adjusted to, and the starting time is 0.4 second, and total starting time is 5.8 seconds.In low pressure to middle pressure, in be pressed onto pressure regulation moment of total head, electric current does not have impact, has reached starting steadily, line voltage ripple disable, the effect that the starting time is short.
Combined voltage regulation start-control device by the 45KW motor confirms that through four wheat harvesting periods industry actual motion this device is effective, reliable operation.
Fig. 5 is m=2, and the combined voltage regulation start-control device autotransformer winding of n=3 connects electrical schematic diagram.
Fig. 6 is m=2, the combined voltage regulation start-control device main circuit schematic diagram of n=3.
Fig. 7 is m=2, the combined voltage regulation start-control device control circuit schematic diagram of n=3.
Fig. 5 is the tail end U at the autotransformer winding of Fig. 1
5, V
5, W
5Increase a part of winding again, and then increase a star interface U
6, V
6, W
6
Fig. 6 is the tail end U at the transformer of the main circuit of Fig. 2
5, V
5, W
5Increase a part of winding again and increase a star interface K switch
4
Fig. 7 is in the control circuit principle of Fig. 3, on the basis of three branch roads in article one electricity loop, increases a branch road again.This route time relay KT
2The time-delay of often opening close contact and contactor K
4often open the auxiliary contact parallel connection after, again with contactor K
3Normally closed auxiliary contact, time relay KT
3The disconnected contact of normally closed time-delay, contactor K
4The circuit and the time relay KT of coil series connection
4Coils from parallel connection of coils after circuit be in series.Again with contactor K in the second electricity loop among Fig. 3
3Normal growth auxiliary contact be changed to contactor K
4Normal growth auxiliary contact get final product.
Operating principle: among Fig. 6, disconnect K
3After, K
4Close, through time relay KT
3Time-delay disconnects K again
4, close K
CL, reaching the starting of n+1=3+1=4 level, all the other are all identical with Fig. 4 operating principle.
Fig. 8 is m=2, and the combined voltage regulation start-control device autotransformer winding of n=4 connects schematic diagram.
Fig. 9 is m=2, the combined voltage regulation start-control device main circuit schematic diagram of n=4.
Figure 10 is m=2, the combined voltage regulation start-control device control circuit schematic diagram of n=4.
Fig. 8 is the tail end U in the Transformer Winding of Fig. 5
6, V
6, W
6Increase a part of winding again, and then increase a star interface U
7, V
7, W
7
Fig. 9 is the tail end U at the transformer of the main circuit of Fig. 6
6, V
6, W
6Increase a part of winding again and increase a star interface K switch
5
Figure 10 is in the control circuit principle of Fig. 7, on the basis of four branch roads in article one electricity loop, increases a branch road again, this route time relay KT
3The time-delay of often opening close contact and contactor K
5often open the auxiliary contact parallel connection after, again with contactor K
4Normally closed auxiliary contact, time relay KT
4The disconnected contact of normally closed time-delay, contactor K
5The circuit and the time relay KT of coil series connection
4Coils from parallel connection of coils after circuit be in series.Again with contactor K in the second electricity loop among Fig. 7
4Normally closed interlock be changed to contactor K
5Normally closed auxiliary contact get final product.
Operating principle: among Fig. 9, disconnect K
4After, K
5Close, through time relay KT
4After the time-delay, disconnect K again
5, close K
CL, reach the starting of n+1=4+1=5 level.All the other are all identical with Fig. 6, Fig. 7 operating principle.
Claims (2)
1, a kind of alternating current motor combined voltage regulation start-control device, comprise alternating current motor, the autotransformer that has only a star interface, with the main circuit that this transformer and three phase mains connect, correspondence is connected to the control circuit of any two-phase in this motor three phase mains; It is characterized in that:
(1) be the autotransformer reconfiguration that is provided with a star interface autotransformer with n star interface, n is arbitrary positive integer in 2 to 10; To the coil segment between first star interface, be provided with the tap of m selective special connection motor at this power of transformer head end, m is arbitrary positive integer of 1 to 10, connects a contactor for each star interface of autotransformer again;
(2) main circuit of this device comprises each corresponding connection of lower end of any three-phase contactor that connects with the three phase mains end of alternating current machine in each phase m tap of 3-phase autotransformer; The tap of the star interface of 3-phase autotransformer n the corresponding turn ratio respectively is connected to a join end of angle tentaculum of three of the required turn ratio asterism of short circuit, and its other end respectively is connected into short circuit;
(3) control circuit of this device by the electric loop of article one electricity loop and second in parallel after, again with button S
1Normally closed interlock series connection constitute; Article one the electricity loop by the parallel connection of (n+1) bar electricity branch road after, again with operation contactor K
CLNormally closed auxiliary contact be in series, wherein article one branch road is by button S
2Normally open contact and contactor K
2often open the auxiliary contact parallel connection after, again with the contactor K of second asterism of short circuit
3Normally closed auxiliary contact, control K
2Time relay KT
1Normally closed time-delay breaking-off contact, contactor K
2Coil series connection; The second branch road is by contactor K
2often open auxiliary, contactor K
1often open the auxiliary contact parallel connection after, again with contactor K
1Coil, time relay KT
1Coils from parallel connection of coils after circuit series connection; From the 3rd branch road to (n-1) bar branch road, its every branch road be successively by the previous short circuit asterism contactor of control often open an asterism contactor behind auxiliary contact and the short circuit often open auxiliary contact in parallel after, again with after the coil that the normally closed time-delay of the time relay of the normally closed auxiliary contact of the previous asterism contactor of control, the back asterism contactor of control disconnects auxilliary head, the back asterism contactor of control connect, be in series with circuit behind the coils from parallel connection of coils of the time relay of controlling a back asterism contactor; Often opening after time-delay closes the normally closed auxiliary contact series connection of auxilliary contact, first and last asterism contactor of the time relay of last asterism contactor of second electricity circuit controls, with the operation contactor often to open auxiliary contact in parallel, be in series with the operation contactor coil again; In control circuit, the contactor of a short circuit asterism of a time relay control;
2, alternating current motor combined voltage regulation start-control device according to claim 1, it is characterized in that when the moment of inertia of alternating current motor dragging system and quiet resistive torque hour, this motor is respectively mutually corresponding to be connected to each phase of tap that voltage is lower in the autotransformer m tap; When the moment of inertia of its dragging system and quiet resistive torque were big, each mutually correspondingly was connected to higher each phase of tap of voltage in the autotransformer m tap this motor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93239269 CN2164613Y (en) | 1993-09-09 | 1993-09-09 | Mixed voltage-regulating starting controller for ac motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93239269 CN2164613Y (en) | 1993-09-09 | 1993-09-09 | Mixed voltage-regulating starting controller for ac motor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2164613Y true CN2164613Y (en) | 1994-05-11 |
Family
ID=33813831
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 93239269 Expired - Fee Related CN2164613Y (en) | 1993-09-09 | 1993-09-09 | Mixed voltage-regulating starting controller for ac motor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2164613Y (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101860285A (en) * | 2010-05-11 | 2010-10-13 | 宁波高新区宁变电力设备有限公司 | Autotransformer device and starting method for soft start of high-power motor |
| CN105119534A (en) * | 2015-10-09 | 2015-12-02 | 重庆大学 | Squirrel cage motor voltage regulation stability control starting control device |
| CN106655968A (en) * | 2016-10-27 | 2017-05-10 | 李洪广 | Automatic shift system based on AC motor, and AC motor |
-
1993
- 1993-09-09 CN CN 93239269 patent/CN2164613Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101860285A (en) * | 2010-05-11 | 2010-10-13 | 宁波高新区宁变电力设备有限公司 | Autotransformer device and starting method for soft start of high-power motor |
| CN105119534A (en) * | 2015-10-09 | 2015-12-02 | 重庆大学 | Squirrel cage motor voltage regulation stability control starting control device |
| CN106655968A (en) * | 2016-10-27 | 2017-05-10 | 李洪广 | Automatic shift system based on AC motor, and AC motor |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |