CN205900232U - Bank bridge main transformer's magnetization device in advance - Google Patents
Bank bridge main transformer's magnetization device in advance Download PDFInfo
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- CN205900232U CN205900232U CN201620853600.7U CN201620853600U CN205900232U CN 205900232 U CN205900232 U CN 205900232U CN 201620853600 U CN201620853600 U CN 201620853600U CN 205900232 U CN205900232 U CN 205900232U
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Abstract
The utility model provides a bank bridge main transformer's magnetization device in advance. Magnetization device includes major loop and control circuit in advance. Wherein the major loop is including assisting transformer, excitation transformer, first contactor and second contactor in advance, and the secondary side of assisting the transformer is connected through the first contactor and the once side of excitation transformer in advance, and the secondary side of excitation transformer is connected through second contactor and main transformer's secondary side, control circuit is used for controlling the actuation of first contactor and second contactor, includes the control transformer who is connected with the secondary side of assisting the transformer, reach with control transformer be connected first to fourth parallel branch. The utility model provides a pair of bank bridge main transformer's magnetization device in advance can carry out excitation in advance to main transformer before main transformer closes a floodgate to reduction excitation surge current reaches the influence of electric wire netting on every side main transformer's impact.
Description
Technical field
This utility model is applied to safe power supply technical field, is related to a kind of pre-magnetizing device of bank bridge main transformer.
Background technology
In steady-state operation, no load excitation electric current is the 2%～10% of rated current to the main transformer of bank bridge, but in zero load
When putting into electrical network, due to the iron core magnetic flux saturation of main transformer and the nonlinear characteristic of core material, very big encouraging can be produced
Magnetic shoves, and its amplitude can reach the decades of times of rated current.This excitation surge current can be to power system and main transformer band itself
Carry out a series of harm, for example: the insulation of infringement main transformer, so that main transformer winding mechanical stress is increased, lead to main transformer pressure
Device winding deformation；Lead to the misoperation of main transformer protection device, cause the decline of the electrical network quality of power supply (to include substantial amounts of high frequency
Harmonic wave), cause the resonance phenomena in electrical network；Cause electromagnetic interference, normal operation of impact surrounding devices etc..Additionally, in country
Under the call of energy-saving and emission-reduction, a lot of harbours can close main transformer to reduce electric power energy consumption when equipment is not in a hurry.But frequency
Numerous is electric to main transformer and periphery to the excitation surge current produced by main transformer power on/off being higher than 8～15 times of rated current
Equipment all can bring different infringements, or even main transformer can be made to trip and not close.
At present, the problems referred to above existing in An Qiao field also do not have good solution.With reference to other industry, solve class
Method like problem has:
1st, in the primary side series resistance of main transformer, first switching-on resistance branch road, by resistance branch short circuit after time delay, make change
Depressor puts into operation.This series resistance one side can limit the size of excitation surge current, in addition can make transient state magnetic flux rapid decay, from
And suppress excitation surge current.But the method is relatively costly, and it is in primary side series resistance, there is certain security risk.
2nd, in main transformer low-pressure side shunt capacitance, the flux polarity of low-pressure side generation and on high-tension side flux polarity phase are made
Instead, cancel out each other, in suppression winding, magnetic flux reaches saturation, thus preventing the generation of excitation surge current during idle-loaded switching-on.But, due to
Capacitance size is difficult to determine, in therefore applying in practice, the method seldom adopts.
Utility model content
The technical problems to be solved in the utility model is to provide a kind of pre-magnetizing device of bank bridge main transformer, can lead
Before Transformer Close, pre-excitation is carried out to main transformer, to reduce excitation surge current to the impact of main transformer and to electricity around
The impact of net.
For solving above-mentioned technical problem, this utility model provides a kind of pre-magnetizing device of bank bridge main transformer, including master
Loop and control loop,
Described major loop includes auxiliary transformator, pre-excitation transformator, first contactor and second contactor, described auxiliary transformation
The secondary side of device is connected with the primary side of described pre-excitation transformator through described first contactor, described exciting transformer secondary
Side is connected with the secondary side of described main transformer through second contactor；
Described control loop is used for controlling the adhesive of described first contactor and second contactor, including with described auxiliary transformation
The control transformator that the secondary side of device connects, and first to fourth parallel branch being connected with described control transformator；
First parallel branch includes the coil starting pre exciting switch and the first relay connected；
Second parallel branch includes the coil stopping pre exciting switch and the second relay connected；
3rd parallel branch include the normally opened contact of described first relay, the auxiliary contact of described first, second catalyst,
The normally-closed contact of described second relay and the coil of described first, second catalyst, the auxiliary of described first, second catalyst touches
Point series connection after in parallel with the normally opened contact of described first relay, after the coils from parallel connection of coils of described first, second catalyst with described
The normally opened contact of the first relay, the normally-closed contact series connection of described second relay；
4th parallel branch includes the line of the auxiliary contact of described first, second catalyst and the first time-delay relay connected
Circle；
Wherein, after described beginning pre exciting switch closure, the coil of described first relay obtains electric, described first relay
Normally opened contact closure, so that the coil of described first, second catalyst is obtained electric, the auxiliary contact of described first, second catalyst is closed
Close, described pre-excitation transformator carries out pre-magnetizing to described main transformer；The coil of described first time-delay relay obtains electric, is prolonging
After long first specifies the time, the normally opened contact of described first time-delay relay is made to close, to close described stopping pre exciting switch, institute
The coil stating the second relay obtains electric, and the normally-closed contact of described second relay is opened, and makes the line of described first, second catalyst
Circle dead electricity, the auxiliary contact of described first, second catalyst is opened, and described pre-excitation transformator stops described main transformer is carried out
Pre-magnetizing.
According to an embodiment of the present utility model, described 3rd parallel branch also includes the line of the second time-delay relay
Circle and normally-closed contact, after the normally opened contact of described first relay closes, the coil of described second time-delay relay obtain electric,
After extending for the second specified time, so that the normally-closed contact of described second time-delay relay is opened, make described first, second catalyst
Coil losing electricity, the auxiliary contact of described first, second catalyst is opened, and described pre-excitation transformator stops described main transformer is entered
Row pre-magnetizing；Described second specifies the time to be more than described first specifies the time.
According to an embodiment of the present utility model, described second specifies the time to be 10s.
According to an embodiment of the present utility model, also include the first air switch, described first air switch is connected on
Between the secondary side of described auxiliary transformator and described first contactor, described control transformator connects through described first air switch
The secondary side of described auxiliary transformator.
According to an embodiment of the present utility model, also include the second air switch, described second air switch is connected on
Between the secondary side of described pre-excitation transformator and described second contactor, the auxiliary normally opened contact string of described second air switch
It is associated in described 3rd parallel branch.
According to an embodiment of the present utility model, also include high-voltage board, for controlling described beginning pre exciting switch and institute
State stopping pre exciting switch work.
According to an embodiment of the present utility model, described first specifies the time to be 4s.
A kind of pre-magnetizing device of bank bridge main transformer that this utility model provides, by preliminary filling magnetic transformer to main transformer pressure
Device carries out pre-excitation, to reduce the impact to the impact of main transformer and to electrical network around for the excitation surge current.
Brief description
It is for providing, this utility model to be further understood from including accompanying drawing, they are included and constitute of the application
Point, accompanying drawing shows embodiment of the present utility model, and plays the effect explaining this utility model principle together with this specification.
In accompanying drawing:
Fig. 1 shows the circuit theory schematic diagram of an embodiment of the present utility model.
Fig. 2 shows the circuit theory schematic diagram of the normally opened contact comprising the first time-delay relay.
Specific embodiment
Now with detailed reference to Description of Drawings embodiment of the present utility model.In the case of any possible, all attached
In figure will represent same or analogous part using identical labelling.Although additionally, the term used in this utility model
It is to select from public term, but some terms in this utility model description mentioned are probably applicant
Come selection, the explanation in the relevant portion of description herein of its detailed meanings by his or her judgement.In addition it is desirable to not only
Pass through used actual terms, and be also to the meaning that contained by each term and understand this utility model.
Fig. 1 shows the circuit theory schematic diagram of an embodiment of the present utility model.Fig. 2 shows and comprises the first time delay
The circuit theory schematic diagram of the normally opened contact of relay.As illustrated, a kind of pre-magnetizing device 100 of bank bridge main transformer includes
Major loop and control loop.
Major loop includes auxiliary transformator, pre-excitation transformator 10, first contactor q1 and second contactor q2, auxiliary transformator
Secondary side 20 be connected with the primary side of pre-excitation transformator 10 through first contactor q1, the secondary side of exciting transformer 10 is through
Two catalyst q2 are connected with the secondary side 30 of main transformer.
Control loop is used for controlling the adhesive of first contactor q1 and second contactor q2.Control loop includes and auxiliary transformation
The control transformator t1 that the secondary side 20 of device connects.Control loop also include with control that transformator t1 is connected first to fourth simultaneously
Connection branch road.The power supply of control loop is derived from auxiliary transformator, and the three-phase alternating current of auxiliary Circuit Fault on Secondary Transformer 20 is through controlling transformator
It is changed into the rated voltage of each parallel branch after t1.
First parallel branch includes the coil k1.1 of beginning pre exciting switch s1 and the first relay k1 connecting.
Second parallel branch includes the coil k2.1 of stopping pre exciting switch s2 and the second relay k2 connecting.
3rd parallel branch includes the normally opened contact k1.2 of the first relay k1, the auxiliary of first, second catalyst q1, q2 touches
Point q1.2, coil q1.1, q2.1 of q2.2, the normally-closed contact k2.2 of the second relay k2 and first, second catalyst q1, q2,
It is in parallel with the normally opened contact k1.2 of the first relay k1 after auxiliary contact q1.2, q2.2 series connection of first, second catalyst q1, q2,
After coil q1.1, q2.1 parallel connection of first, second catalyst q1, q2 with the normally opened contact k1.2 of the first relay k1, second continue
The normally-closed contact k2.2 series connection of electrical equipment k2.
4th parallel branch includes auxiliary contact q1.2, q2.2 of first, second catalyst q1, q2 and the first time delay connected
The coil k3.1 of relay k3.
The work process of the pre-magnetizing device 100 of bank bridge main transformer is as follows:
When control loop switches on power, press beginning pre exciting switch s1, after starting pre exciting switch s1 closure, the first relay
The coil k1.1 of device k1 obtains electric, the normally opened contact k1.2 closure of the first relay k1, makes the line of first, second catalyst q1, q2
Circle q1.1, q2.1 obtain electric, and then auxiliary contact q1.2, q2.2 closure of first, second catalyst q1, q2.First, second contact
Device q1, q2 close, and major loop turns on, and the Power convert from auxiliary transformator is become the specified of main transformer by pre-excitation transformator 10
Voltage, and then pre-magnetizing is carried out to main transformer.
When the first relay k1 adhesive, the coil k3.1 of the first time-delay relay k3 obtains electric, when extending first and specifying
Between after t1, with reference to Fig. 2, so that the normally opened contact k3.2 of the first time-delay relay k3 is closed, normally opened contact k3.2 closure can trigger master
Transformer Close obtains electric, and triggering simultaneously stops pre exciting switch and closes so that the coil k2.1 of the second relay k2 obtains electric, and second continues
The normally-closed contact k2.2 of electrical equipment k2 opens, and makes coil q1.1, q2.1 dead electricity of first, second catalyst q1, q2, and first, second
Auxiliary contact q1.2, q2.2 of catalyst q1, q2 open.First, second catalyst q1, q2 opens, and major loop disconnects, and pre-excitation becomes
Depressor 10 stops carrying out pre-magnetizing to main transformer.In one embodiment, first time t1 is specified to be 4s.
Further, the 3rd parallel branch also includes the coil k4.1 and normally-closed contact k4.2 of the second time-delay relay k4.
After the normally opened contact k1.2 of the first relay k1 closes, the coil k4.1 of the second time-delay relay k4 obtains electric, is extending second
After specified time t2, so that the normally-closed contact k4.2 of the second time-delay relay k4 is opened, make the line of first, second catalyst q1, q2
Circle dead electricity.Auxiliary contact q1.2, q2.2 of first, second catalyst q1, q2 open, and first, second catalyst q1, q2 opens, main
Loop disconnects, and pre-excitation transformator 10 stops carrying out pre-magnetizing to main transformer.Wherein, second time t2 is specified to be more than the first finger
Fix time t1.
Second time-delay relay k4 plays a protective role.If the first time-delay relay k3 fails to trigger main transformer conjunction
Lock, then force to disconnect first, second catalyst q1 and q2 after specifying time t2 second, to stop to main transformer pre-magnetizing.
In one embodiment, second time t2 is specified to be 10s.
It is preferred that pre-magnetizing device 100 also includes the first air switch cb3, the first air switch cb3 is connected on auxiliary transformation
Between the secondary side 20 of device and first contactor q1, transformator t1 is controlled to connect the two of auxiliary transformator through the first air switch cb3
Secondary side.
It is preferred that pre-magnetizing device 100 also includes the second air switch cb4, the second air switch cb4 is connected on pre-excitation
Between the secondary side of transformator 10 and second contactor q2.The auxiliary normally opened contact cb4.2 of the second air switch cb4 is connected on
In three parallel branches, become and control coil q1.1, q2.1 of first, second catalyst q1, q2 to obtain an electric condition.
It is preferred that pre-magnetizing device 100 also includes high-voltage board.As illustrated, high-voltage board 40 starts to magnetize out for control
Close s1 and stop pre exciting switch s2 work.In fact, starting pre exciting switch s1 and stopping pre exciting switch s2 can be arranged on high pressure
In cabinet 40.Additionally, the normally-closed contact k4.2 of the second time-delay relay k4 is connected in the remotely control loop of high-voltage board 40.
Taking the practical operation project of applicant as a example and combine accompanying drawing to illustrate each part in pre-magnetizing device 100
Electrical parameter, connected mode and operating process.
The electrical parameter of main transformer: 1600kva, dyn11,10kv/440v.
The electrical parameter of auxiliary transformator: 250kva, dyn11,10kv/380v.
According to main transformer capacity and connection set, choose pre-excitation transformator, the electrical parameter of this pre-excitation transformator:
50kva, ynyn0,380v/440v.For making pre-excitation transformator consistent with main transformer phase angle, therefore pre-excitation transformator adopts
The booster transformer of ynyn0 connection group.
Pre-excitation transformator primary side 20 connects the secondary side of auxiliary transformator, and the secondary side of pre-excitation transformator connects main transformer
Depressor secondary side.It is connected by rigid line with high-voltage board 40, to control the pre-magnetizing process to main transformer.
When pre-magnetizing starts, press the beginning pre exciting switch s1 on high-voltage board 40, now the feed chopper of high-voltage board 40
Do not close a floodgate, only provide the signal that starts to magnetize to the first relay k1 so that first, second catalyst q1, q2 adhesive, major loop
Connection, starts to main transformer secondary side pre-magnetizing.
Magnetize 4 seconds afterwards, the first time-delay relay k3 sends permission switching signal, the main transformer of high-voltage board 40 to high-voltage board 40
Feeder breaker closes a floodgate, and triggering after closing success stops pre exciting switch s2 closure, provides stopping and magnetizes signal to the second relay
K2, the normally-closed contact k2.2 of the second relay k2 opens, and disconnects first, second catalyst q1, q2, and major loop disconnects, main transformer pressure
Device secondary side magnetizes end.
If main transformer feeder breaker closes a floodgate unsuccessfully, the second time-delay relay k4 pressure afterwards in 10 seconds disconnects first, second and connects
Tentaculum q1, q2, stop pre-magnetizing.
If main transformer is provided without this pre-magnetizing device 100 in this project, start excitation surge current and be about primary side volume
Determine electric current 8-15 times, about 739.2a～1386a.After pre-magnetizing device 100, starting excitation surge current does not almost have, that is,
Rated current 92.4a.
A kind of pre-magnetizing device of bank bridge main transformer that this utility model provides has the advantage that
1. the magnetic flux saturation of jumbo main transformer is made by the pre-excitation transformator of low capacity, so will be jumbo
The situation of high current, when main transformer comes into operation, would not occur, main transformer is protected.
2nd, the power supply homology of pre-excitation transformator and main transformer, hereby it is ensured that the phase sequence of voltage and phase angle, it is to avoid
The generation of circulation.
3rd, carry out pre-magnetizing in main transformer secondary side, it is to avoid the potential safety hazard existing when primary side operates.
4th, using ripe relay and catalyst, operation and maintenance low cost, circuit general safety is reliable for control loop.
Those skilled in the art can be obvious, above-mentioned example embodiment of the present utility model can be carried out with various modifications and become
Type is without departing from spirit and scope of the present utility model.Accordingly, it is intended to make this utility model cover in appended claims
And its changing and modification to of the present utility model in the range of equivalent arrangements.
Claims (7)
1. a kind of pre-magnetizing device of bank bridge main transformer, including major loop and control loop it is characterised in that:
Described major loop includes auxiliary transformator, pre-excitation transformator, first contactor and second contactor, described auxiliary transformator
Secondary side is connected with the primary side of described pre-excitation transformator through described first contactor, the secondary side warp of described exciting transformer
Second contactor is connected with the secondary side of described main transformer；
Described control loop is used for controlling the adhesive of described first contactor and second contactor, including with described auxiliary transformator
The control transformator that secondary side connects, and first to fourth parallel branch being connected with described control transformator；
First parallel branch includes the coil starting pre exciting switch and the first relay connected；
Second parallel branch includes the coil stopping pre exciting switch and the second relay connected；
3rd parallel branch includes the normally opened contact of described first relay, the auxiliary contact of described first, second catalyst, described
The normally-closed contact of the second relay and the coil of described first, second catalyst, the auxiliary contact string of described first, second catalyst
In parallel with the normally opened contact of described first relay after connection, with described first after the coils from parallel connection of coils of described first, second catalyst
The normally opened contact of relay, the normally-closed contact series connection of described second relay；
4th parallel branch includes the coil of the auxiliary contact of described first, second catalyst and the first time-delay relay connected；
Wherein, after described beginning pre exciting switch closure, the coil of described first relay obtain electric, described first relay normal
Open the closing of contact, so that the coil of described first, second catalyst is obtained electric, the auxiliary closing of contact of described first, second catalyst, institute
State pre-excitation transformator and pre-magnetizing is carried out to described main transformer；The coil of described first time-delay relay obtains electric, is extending the
After one specifies the time, the normally opened contact of described first time-delay relay is made to close, to close described stopping pre exciting switch, described the
The coil of two relays obtains electric, and the normally-closed contact of described second relay is opened, and makes the deactivation coil of described first, second catalyst
Electricity, the auxiliary contact of described first, second catalyst is opened, and described pre-excitation transformator stops carrying out preliminary filling to described main transformer
Magnetic.
2. pre-magnetizing device as claimed in claim 1 is it is characterised in that described 3rd parallel branch also includes the second time delay and continues
The coil of electrical equipment and normally-closed contact, after the normally opened contact of described first relay closes, the line of described second time-delay relay
Enclose electric, extend second specify the time after, so that the normally-closed contact of described second time-delay relay is opened, make described first, the
The coil losing electricity of two catalysts, the auxiliary contact of described first, second catalyst is opened, and described pre-excitation transformator stops to described
Main transformer carries out pre-magnetizing；
Described second specifies the time to be more than described first specifies the time.
3. pre-magnetizing device as claimed in claim 2 is it is characterised in that described second specifies the time to be 10s.
4. pre-magnetizing device as claimed in claim 1 is it is characterised in that also include the first air switch, described first air
Switch is connected between secondary side and the described first contactor of described auxiliary transformator, and described control transformator is empty through described first
Air cock connects the secondary side of described auxiliary transformator.
5. pre-magnetizing device as claimed in claim 1 is it is characterised in that also include the second air switch, described second air
Switch is connected between secondary side and the described second contactor of described pre-excitation transformator, the auxiliary of described second air switch
Normally opened contact is connected in described 3rd parallel branch.
6. pre-magnetizing device as claimed in claim 1 is it is characterised in that also include high-voltage board, described starts to fill for controlling
Magnetic switch and the work of described stopping pre exciting switch.
7. pre-magnetizing device as claimed in claim 1 is it is characterised in that described first specifies the time to be 4s.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620853600.7U CN205900232U (en) | 2016-08-09 | 2016-08-09 | Bank bridge main transformer's magnetization device in advance |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620853600.7U CN205900232U (en) | 2016-08-09 | 2016-08-09 | Bank bridge main transformer's magnetization device in advance |
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| CN205900232U true CN205900232U (en) | 2017-01-18 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108987075A (en) * | 2018-07-05 | 2018-12-11 | 上海电动工具研究所（集团）有限公司 | Electric system on high-tension transformer based on multistage preliminary filling magnetic function |
| CN110060857A (en) * | 2018-11-29 | 2019-07-26 | 合肥工业大学 | A kind of power transformer that can eliminate excitation surge current and its application method |
| CN114204532A (en) * | 2021-10-25 | 2022-03-18 | 北京无线电测量研究所 | Distribution circuit for reducing starting impact current of transformer in radar system |
| CN117117794A (en) * | 2023-10-12 | 2023-11-24 | 广东省洛仑兹技术股份有限公司 | Transformer pre-magnetizing circuit and control method thereof |
-
2016
- 2016-08-09 CN CN201620853600.7U patent/CN205900232U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108987075A (en) * | 2018-07-05 | 2018-12-11 | 上海电动工具研究所（集团）有限公司 | Electric system on high-tension transformer based on multistage preliminary filling magnetic function |
| CN110060857A (en) * | 2018-11-29 | 2019-07-26 | 合肥工业大学 | A kind of power transformer that can eliminate excitation surge current and its application method |
| CN114204532A (en) * | 2021-10-25 | 2022-03-18 | 北京无线电测量研究所 | Distribution circuit for reducing starting impact current of transformer in radar system |
| CN117117794A (en) * | 2023-10-12 | 2023-11-24 | 广东省洛仑兹技术股份有限公司 | Transformer pre-magnetizing circuit and control method thereof |
| CN117117794B (en) * | 2023-10-12 | 2024-02-27 | 广东省洛仑兹技术股份有限公司 | Transformer pre-magnetizing circuit and control method thereof |
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