CN207542059U - A kind of transformer electromagnetic interference protecting system - Google Patents
A kind of transformer electromagnetic interference protecting system Download PDFInfo
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- CN207542059U CN207542059U CN201721323047.7U CN201721323047U CN207542059U CN 207542059 U CN207542059 U CN 207542059U CN 201721323047 U CN201721323047 U CN 201721323047U CN 207542059 U CN207542059 U CN 207542059U
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Abstract
A kind of transformer electromagnetic interference protecting system, including：The high-pressure side protection equipment for being arranged on high voltage side of transformer and the low-pressure side protection equipment for being arranged on step down side；Wherein described high-pressure side protection equipment includes being connected to the high-pressure side arrester between high-tension cable and ground and is connected to the high-pressure side protective device of high-tension cable and the high voltage side of transformer, and the low-pressure side protection equipment includes being connected to the low-pressure side arrester between low-voltage cable and ground and is connected to the low-pressure side protective device of low-voltage cable and the step down side.Implement the transformer electromagnetic interference protecting system of the utility model; equipment and the low-pressure side of step down side is protected to protect equipment by the high-pressure side for being separately positioned on high voltage side of transformer; light current magnetic disturbance can be protected but also protect the strong electromagnetics such as thunder and lightning; and the resistance value of the ground resistance due to the grounded screen that can become larger, grounded screen manufacture and maintenance cost are relatively low.
Description
Technical field
The utility model is related to field transformer, more specifically to a kind of transformer electromagnetic interference protecting system.
Background technology
Power transformer is one of equipment of most critical in electric system, and it is one in this field to ensure its normal operation
A very important subject.There are many source of damage of transformer, and electromagnetic interference is a wherein critically important factor of damage.Electricity
Magnetic disturbance generally includes strong electromagnetic, for example, the pulse current that generates of direct stroke, indirect lightning strike, switching overvoltage and
Light current magnetic disturbance, such as the high-frequency electromagnetic interference that high-frequency harmonic, the oscillating electromagnetic wave of switching manipulation generation, user equipment generate.
Existing transformer electromagnetic interference protecting system is normally only in transformer both sides zinc oxide surge arresters and ground connection electricity
Net, so as to which electromagnetic energy is released to the earth, so as to be protected to transformer.However such transformer electromagnetic interference shielding
System is primarily present following defect.
1. there is response to overvoltage, that is to say, that as long as interference voltage is no more than the startup voltage of arrester, protection
Pattern would not act, and the characteristics such as frequency, pulsewidth for electromagnetic interference cannot respond to and protect, and arrester
Starting voltage can all select between 1 to 2 times of working voltage.For example the arrester of 380V working voltages is typically chosen startup electricity
Pressure is all in 620V or so, it can be said that the prior art is no any protective capacities to light current magnetic disturbance.
2nd, it is very high to the requirement of grounded screen, the ground resistance of grounded screen is generally required to be less than 10 Ω, and such ground connection
The manufacture cost and maintenance cost of resistance are all very high.
Utility model content
The technical problem to be solved by the present invention is to for the drawbacks described above of the prior art, providing one kind can prevent
Shield light current magnetic disturbance can protect the strong electromagnetics such as thunder and lightning again, and grounded screen manufactures the transformer electromagnetism low with maintenance cost and does
Disturb guard system.
Technical solution is used by the utility model solves its technical problem：Construct a kind of transformer electromagnetic interference shielding
System, including：The high-pressure side protection equipment for being arranged on high voltage side of transformer and the low-pressure side for being arranged on step down side are protected
Protect equipment；Wherein described high-pressure side protection equipment includes the high-pressure side arrester and the connection that are connected between high-tension cable and ground
In high-tension cable and the high-pressure side protective device of the high voltage side of transformer, the low-pressure side protection equipment includes being connected to low pressure
Low-pressure side arrester between cable and ground and the low-pressure side protection dress for being connected to low-voltage cable and the step down side
It puts.
In transformer electromagnetic interference protecting system described in the utility model, the high-pressure side protective device and/or institute
It states low-pressure side protective device and includes differential mode inductors.
In transformer electromagnetic interference protecting system described in the utility model, the high-pressure side protective device and/or institute
It states low-pressure side protective device and further comprises the common-mode inductor connected with the differential mode inductors.
In transformer electromagnetic interference protecting system described in the utility model, the differential mode inductors include high frequency magnetic core
And coil；The common-mode inductor includes at least two co-mode coils and the high-frequency magnetic being arranged between the co-mode coil.
In transformer electromagnetic interference protecting system described in the utility model, the high-pressure side protective device and/or institute
It is the slow device of electromagnetic wave traveling wave to state low-pressure side protection equipment, and the slow device of electromagnetic wave traveling wave includes：Hollow conductive pipe is arranged on
Magnet inside the hollow conductive pipe is arranged between the hollow conductive pipe and the magnet with the magnet and the institute of insulating
The first insulating sleeve of hollow conductive pipe is stated, surround the magnetic sleeve pipe of hollow conductive pipe setting and is arranged on the magnetic
With the second insulating sleeve of the insulate hollow conductive pipe and the magnetic sleeve pipe between property casing and the hollow conductive pipe.
In transformer electromagnetic interference protecting system described in the utility model, the hollow conductive pipe is opens up on outer wall
The cylindrical metal tube of continuous helical slot.
In transformer electromagnetic interference protecting system described in the utility model, the magnet is is threaded through the cylinder
Metal tube center bar magnet, the cylindrical metal tube end walls center setting for the bar magnet by first through hole.
In transformer electromagnetic interference protecting system described in the utility model, in the end walls of the cylindrical metal tube
Multiple second through-holes are placed equidistant with around the first through hole.
In transformer electromagnetic interference protecting system described in the utility model, further comprise being arranged on described hollow lead
The fixedly connected part at fulgurite both ends；The fixedly connected part is described hollow to insulate including being set in the hollow conductive pipe both ends
Contact tube and annular insulation Jie's piece of the magnetic sleeve pipe and the conductive fixed cover being fixed in the magnetic sleeve pipe；It is described
Multiple third through-holes are set on the outer wall of conductive fixed cover.
In transformer electromagnetic interference protecting system described in the utility model, the transformer is single-phase transformer or three
Phase transformer, the earthing of casing of the transformer.
Implement the transformer electromagnetic interference protecting system of the utility model, by the height for being separately positioned on high voltage side of transformer
Side protection equipment and the low-pressure side protection equipment of step down side are pressed, light current magnetic disturbance can be protected but also protect thunder and lightning etc.
Strong electromagnetic, and the resistance value of the ground resistance due to the grounded screen that can become larger, grounded screen manufacture and maintenance cost
It is relatively low.Further, as a result of common-mode inductor, therefore there can be more efficient impedance to avoid suppression common mode electromagnetic interference
Filtration result.
Description of the drawings
Below in conjunction with accompanying drawings and embodiments, the utility model is described in further detail, in attached drawing：
Fig. 1 is the functional block diagram of the first embodiment of the transformer electromagnetic interference protecting system of the utility model；
Fig. 2 is the circuit diagram of the second embodiment of the transformer electromagnetic interference protecting system of the utility model；
Fig. 3 is the circuit diagram of the 3rd embodiment of the transformer electromagnetic interference protecting system of the utility model；
Fig. 4 is the circuit diagram of the fourth embodiment of the transformer electromagnetic interference protecting system of the utility model；
Fig. 5 is the circuit diagram of the 5th embodiment of the transformer electromagnetic interference protecting system of the utility model；
Fig. 6 is the structural blast of the slow device of electromagnetic wave traveling wave of the transformer electromagnetic interference protecting system shown in Fig. 4 or 5
Figure；
Fig. 7 is the front view of the cylindrical metal tube of the slow device of electromagnetic wave traveling wave shown in fig. 6；
Fig. 8 is the oblique view of the cylindrical metal tube of the slow device of electromagnetic wave traveling wave shown in fig. 6.
Specific embodiment
In order to make the purpose of the utility model, technical solutions and advantages more clearly understood, below in conjunction with attached drawing and implementation
Example, the present invention is further described in detail.It should be appreciated that specific embodiment described herein is only used to explain
The utility model is not used to limit the utility model.
As shown in Figure 1, the transformer electromagnetic interference protecting system of the utility model, the change including being arranged on transformer 200
The on high-tension side high-pressure side protection equipment 100 of depressor and the low-pressure side protection equipment 300 for being arranged on step down side.The height
Protection equipment 100 in pressure side includes being connected to the high-pressure side arrester 110 between high-tension cable and ground and being connected to high-tension cable
With the high-pressure side protective device 120 of the high voltage side of transformer.The low-pressure side protection equipment 300 includes being connected to low-voltage cable
Low-pressure side arrester 310 between ground and the low-pressure side protective device for being connected to low-voltage cable and the step down side
320。
In the utility model, arrester 311,312,111,112 can be with varistor, electric discharge ligament arrester, oxygen
Change zinc arrester, ceramic discharge tube, Transient Suppression Diode, semiconductor discharge tube etc. device or its various combination.In this reality
In novel, in addition to single-phase transformer, the transformer electromagnetic interference protecting system can be applied to various transformer equipments,
Such as three-phase transformer, 50HZ transformers, 60HZ transformers, 400Hz transformers, high frequency transformer, isolating transformer, adjustable electric
Pressure transformer etc..
In a preferred embodiment of the utility model, the high-pressure side protective device 120 and low-pressure side protection
Device 320 can be various types inductor, resistor, and wave filter etc. may be the same or different.Due to described
High-pressure side protective device 120 is connected between high voltage side of transformer and ground together with high-pressure side arrester 110, and the low-pressure side
Protective device 320 and the low-pressure side arrester 310 are connected between step down side and ground together, either from low tension
The electromagnetic interference traveling wave that the electromagnetic interference traveling wave that cable transmits still is transmitted from high-tension cable, strong electromagnetic traveling wave therein is through keeping away
Thunder device is discharged into the earth, and light current magnetic disturbance traveling wave is dropped by high-pressure side protective device 120 and the low-pressure side protective device 320
Low or conversion and reduce impact to transformer.And strong electromagnetic can only be discharged into the earth by arrester at this time, therefore i.e.
Make ground resistance is larger will not influence energy release.
Implement the transformer electromagnetic interference protecting system of the utility model, by the height for being separately positioned on high voltage side of transformer
Side protection equipment and the low-pressure side protection equipment of step down side are pressed, light current magnetic disturbance can be protected but also protect thunder and lightning etc.
Strong electromagnetic, and the resistance value of the ground resistance due to the grounded screen that can become larger, grounded screen manufacture and maintenance cost
It is relatively low.
Fig. 2 is the circuit diagram of the second embodiment of the transformer electromagnetic interference protecting system of the utility model.Fig. 2 with
The form of single-phase transformer is described as follows the transformer electromagnetic interference protecting system of the utility model.As shown in Fig. 2, this practicality
Novel transformer electromagnetic interference protecting system includes being arranged on the high-pressure side protection of the high voltage side of transformer of single-phase transformer 210
Equipment 100 and the low-pressure side protection equipment 300 for being arranged on step down side.In the present embodiment, the high-pressure side protection
Equipment 100 includes the first high-pressure side being connected between the first end of the high voltage side of transformer of the single-phase transformer 210 and ground
It protects the second high-pressure side protected equipment and be connected between the second end of the high voltage side of transformer of the single-phase transformer and ground
Equipment.And the low-pressure side protection equipment 300 is connected to first end, the second end of the step down side of the single-phase transformer
Between ground.
In the present embodiment, the first high-pressure side protection equipment includes the first end and transformer that are connected to high-tension cable
Differential mode inductors 121 between on high-tension side first end and the arrester 111 being connected between the first end of high-tension cable and ground.
The second high-pressure side protection equipment includes being connected between the second end of high-tension cable and the second end of high voltage side of transformer
Differential mode inductors 122 and the arrester 112 being connected between the second end of high-tension cable and ground.In the preferred reality of the utility model
It applies in example, the differential mode inductors 121 and differential mode inductors 122 can be made of high frequency magnetic core and coil, respectively constitute Fig. 1
Shown high-pressure side protective device 120.
In the present embodiment, low-pressure side protection equipment 300 include common-mode inductor 321 and differential mode inductors 322,
The 323 low-pressure side protective devices 320 formed and arrester 311,312.As shown in Fig. 2, common-mode inductor 321 includes common mode
Coil 3211,3212 and high-frequency magnetic 3212.The first end of differential mode inductors 322 connects the change of the single-phase transformer 210
The first end of depressor low-pressure side, the first end of second end connection co-mode coil 3211, the second end of the co-mode coil 3211 connect
Connect the first end of low-voltage cable.The first end of differential mode inductors 323 connects the step down side of the single-phase transformer 210
The first end of second end, second end connection co-mode coil 3213, the second end connection low-voltage cable of the co-mode coil 3213
Second end.High-frequency magnetic 3212 is arranged between co-mode coil 3211 and co-mode coil 3213.Arrester 311 is connected to described low
Between the first end and ground of voltage cable and the arrester 312 is connected between second end and the ground of the low-voltage cable.At this
It, can be by the earthing of casing of the transformer 200 in the preferred embodiment of utility model.In the further excellent of the utility model
It selects in embodiment, the second end of the low-voltage cable can also be grounded.
The principle of the present embodiment is described as follows below based on Fig. 2：
Whether the strong electromagnetic of thunder and lightning etc or light current magnetic disturbance are all with electromagnetic running wave on cable conductor
Mode is transmitted, electromagnetic running wave can prolong transformer high voltage cable or type low-voltage cable from being distally transmitted to transformer, it might even be possible to
It is transmitted simultaneously from high and low pressure side to transformer.
The electromagnetic interference traveling wave transmitted from certain high voltage cable can first pass around " high-pressure side protection equipment ".Such as
Fruit electromagnetic interference traveling wave is strong electromagnetic, and the differential mode inductors meeting impedance connected at this moment high-pressure side protection equipment is flowed through in it
The variation of portion's electric current, the effect brought are the rapid voltage for promoting high pressure side inlet.At this moment the arrester of entrance can be rapidly reached
Its startup voltage is simultaneously connected rapidly, and interference electromagnetic wave energy is released to the earth.If electromagnetic interference traveling wave is done for light current magnetic
It disturbs, the startup voltage of arrester is not achieved, then differential mode inductors can play inductance filter, reduce the slope of interference waveform
And part energy is converted to thermal dissipation, so as to reduce impact of the electromagnetic interference to transformer.
The electromagnetic interference traveling wave transmitted from certain type low-voltage cable can first pass around low-pressure side protection equipment.Electromagnetism
Interference traveling wave is strong electromagnetic, and the low-pressure side protective device meeting impedance connected at this moment low-pressure side protection equipment flows through it
The variation of internal current, the effect brought are the rapid voltage for promoting low pressure side inlet.At this moment the arrester meeting of low pressure side inlet
It is rapidly reached its startup voltage and is connected rapidly, interference electromagnetic wave energy is released to the earth.If electromagnetic interference traveling wave is
The startup voltage of arrester is not achieved in light current magnetic disturbance, then differential mode inductors can play inductance filter, reduces interference wave
Part energy is simultaneously converted to thermal dissipation by the slope of shape, so as to reduce impact of the electromagnetic interference to transformer.
Why existing guard technology wishes that the ground resistance of grounded screen is the smaller the better, when being because of arrester conducting, electricity
Magnetic disturbance energy can be divided into 2 parallel shunt branches in arrester front end, flow to inside transformer, another way flow direction ground connection all the way
Resistance.So ground resistance is smaller, the current energy for flowing to the earth is more, better to the protection of transformer, ground resistance
Play the role of adjusting interfering energy current drain ratio.And apply the transformer electromagnetic interference protecting system of the utility model
Afterwards, the energy of electromagnetic interference has been also divided into 2 parallel shunt branches when arrester is connected, but flows to a branch of transformer
It is blocked, lightning current only has a Zhi Luxiang the earth to release, and ground resistance at this time no longer takes on adjusting current drain ratio
Effect, even if ground resistance becomes larger it is also ensured that interfering energy is completely to greatly releasing.Therefore, it is new using this practicality
After the system of type can appropriate amplifying transformer earth mat grounding resistance, without influencing its protective capacities.
Further, due to common-mode inductor of connecting in protecting equipment in low-pressure side, for each cable of low-pressure side
On, while suppression common mode electromagnetic interference similar in the direction same size being propagated through, there is more efficient impedance filtration result.
In other preferred embodiments of the utility model, the high-pressure side protective device can also include and differential mode inductance
The common-mode inductor of device series connection, set-up mode can refer to low-pressure side protective device.And in a simplification of the utility model
In embodiment, the high-pressure side protective device and the low-pressure side protective device can only include differential mode inductors.Based on this
The introduction of utility model, those skilled in the art know how to carry out above-mentioned setting.
In the utility model, arrester 311,312,111,112 can be with varistor, electric discharge ligament arrester, oxygen
Change zinc arrester, ceramic discharge tube, Transient Suppression Diode, semiconductor discharge tube etc. device or its various combination.
In the utility model, in addition to single-phase transformer, the transformer electromagnetic interference protecting system can be applied to
Various transformer equipments, for example, three-phase transformer, 50HZ transformers, 60HZ transformers, 400Hz transformers, high frequency transformer, every
From transformer, voltage regulating transformer etc..
Fig. 3 is the circuit diagram of the 3rd embodiment of the transformer electromagnetic interference protecting system of the utility model.Fig. 3 with
The transformer electromagnetic interference protecting system of the utility model is illustrated for three-phase transformer.As shown in figure 3, this practicality is new
The high-pressure side protection that the transformer electromagnetic interference protecting system of type includes being arranged on the high voltage side of transformer of three-phase transformer 220 is set
Standby 100 and it is arranged on the low-pressure side protection equipment 300 of step down side.In the present embodiment, the high-pressure side protection is set
Standby 100 the first high-pressure sides included between the first phase and ground of high voltage side of transformer for being connected to the three-phase transformer 220 are protected
Protect the second high-pressure side protection between equipment, the second phase and ground of the high voltage side of transformer for being connected to the three-phase transformer 220
Equipment and be connected to the three-phase transformer 220 high voltage side of transformer third phase and ground between third high-pressure side protection
Equipment.
And low-pressure side protection equipment 300 be connected to the step down side of the three-phase transformer 220 the first phase,
Between second phase, third phase and ground.
In the present embodiment, the first high-pressure side protection equipment includes the first end and transformer that are connected to high-tension cable
Differential mode inductors 121 between on high-tension side first phase and the arrester 111 being connected between the first end of high-tension cable and ground.
The second high-pressure side protection equipment includes being connected between the second end of high-tension cable and the second phase of high voltage side of transformer
Differential mode inductors 122 and the arrester 112 being connected between the second end of high-tension cable and ground.The third high-pressure side protection is set
It the standby differential mode inductors 123 for including being connected between the third end of high-tension cable and the second phase of high voltage side of transformer and is connected to
Arrester 113 between the second end and ground of high-tension cable.In the preferred embodiment of the utility model, the differential mode inductors
121st, it 122 and 123 can be made of high frequency magnetic core and coil, respectively constitute high-pressure side protective device 120 shown in FIG. 1.
In the present embodiment, low-pressure side protection equipment 300 include common-mode inductor 326 and differential mode inductors 322,
323rd, the 324 and 325 low-pressure side protective devices 320 formed and three groups of arresters.As shown in figure 3, common-mode inductor 326 wraps
Include four co-mode coils 3262 and three high-frequency magnetics 3261.The first end of differential mode inductors 322 connects three phase-change pressure
The first phase, the second end of the step down side of device 220 connect the first end of the first co-mode coil 3262, the co-mode coil
The first end of 3262 second end connection low-voltage cable.The first end of differential mode inductors 323 connects the three-phase transformer 220
Second phase of step down side, second end connect the first end of the second co-mode coil 3262, and the of the co-mode coil 3262
Two ends connect the second end of low-voltage cable.The transformer that the first end of differential mode inductors 324 connects the three-phase transformer 220 is low
Press the third phase of side, the first end of second end connection third co-mode coil 3262, the second end connection of the co-mode coil 3262
The third end of low-voltage cable.The first end of differential mode inductors 325 connects the zero of the step down side of the three-phase transformer 220
Line phase, second end connect the first end of the 4th co-mode coil 3262, the second end connection low-voltage cable of the co-mode coil 3262
The 4th end.As shown in figure 3, the shell of three-phase transformer 220 is grounded together with the 4th end of low-voltage cable.
In other preferred embodiments of the utility model, the high-pressure side protective device can also include and differential mode inductance
The common-mode inductor of device series connection, set-up mode can refer to low-pressure side protective device.And in a simplification of the utility model
In embodiment, the high-pressure side protective device and the low-pressure side protective device can only include differential mode inductors.Based on this
The introduction of utility model, those skilled in the art know how to carry out above-mentioned setting.
Further as shown in figure 3, in the present embodiment, three groups of arresters are respectively by varistor 3121 and discharge tube 3122
Composition.One group of varistor 3121 and discharge tube 3122 are connected to after connecting between the first end of low-voltage cable and ground.One group of pressure
Quick resistance 3121 and discharge tube 3122 are connected to after connecting between the second end of low-voltage cable and ground.One group of 3121 He of varistor
Discharge tube 3122 is connected to after connecting between the third end of low-voltage cable and ground.Certainly in other preferred implementations of the utility model
In example, other kinds of arrester can also be used to set.
Implement the transformer electromagnetic interference protecting system of the utility model, by the height for being separately positioned on high voltage side of transformer
Side protection equipment and the low-pressure side protection equipment of step down side are pressed, light current magnetic disturbance can be protected but also protect thunder and lightning etc.
Strong electromagnetic, and the resistance value of the ground resistance due to the grounded screen that can become larger, grounded screen manufacture and maintenance cost
It is relatively low.Further, as a result of common-mode inductor, therefore there can be more efficient impedance to avoid suppression common mode electromagnetic interference
Filtration result.
Fig. 4 is the circuit diagram of the fourth embodiment of the transformer electromagnetic interference protecting system of the utility model.Fig. 4 is
It is illustrated by taking single-phase transformer as an example.As shown in figure 4, the transformer electromagnetic interference protecting system of the utility model, including setting
It puts and protects equipment 100 in the high-pressure side of the high voltage side of transformer of single-phase transformer 210 and be arranged on the low of step down side
Press side protection equipment 300.The high-pressure side protection equipment 100 includes the high-pressure side arrester being connected between high-tension cable and ground
110 and it is connected to the high-pressure side protective device 120 of high-tension cable and the high voltage side of transformer.The low-pressure side protects equipment
300 include being connected to the low-pressure side arrester 310 between low-voltage cable and ground and are connected to low-voltage cable and the transformer
The low-pressure side protective device 320 of low-pressure side.
In the present embodiment, the first high-pressure side protection equipment includes the first end and transformer that are connected to high-tension cable
It the slow device 124 of electromagnetic wave traveling wave between on high-tension side first end and is connected to lightning-arrest between the first end of high-tension cable and ground
Device 111.The second high-pressure side protection equipment includes being connected to the second end of high-tension cable and the second end of high voltage side of transformer
Between the slow device 125 of electromagnetic wave traveling wave and the arrester 112 being connected between the second end of high-tension cable and ground.The electromagnetism
The slow device 124 of wave traveling wave forms high-pressure side protective device 120 shown in FIG. 1.
In the present embodiment, the low-pressure side protection equipment 300 includes the slow device 328,329 of electromagnetic wave traveling wave and takes shelter from the thunder
Device.The slow composition of device 328,329 of electromagnetic wave traveling wave low-pressure side protective device 320 shown in FIG. 1, and 3131 He of varistor
Discharge tube 3132 forms low-pressure side arrester 310 shown in FIG. 1.As shown in figure 4, the input terminal of the slow device 328 of electromagnetic wave traveling wave
Connect the first end of the step down side of the single-phase transformer 210, the first end of output terminal connection varistor 3131.Pressure
The second end of quick resistance 3131 is grounded through discharge tube 3132.The earthing of casing of the single-phase transformer 210.Electromagnetic wave traveling wave is slow
The input terminal of device 329 connects the second end of the step down side of the single-phase transformer 210, output terminal ground connection.
In a preferred embodiment of the utility model, the slow device 124,125,328,329 of electromagnetic wave traveling wave can
To be various types of slow devices of electromagnetic wave traveling wave, may be the same or different.Due to the high-pressure side protective device
120 are connected between high voltage side of transformer and ground together with high-pressure side arrester 110, and 320 He of low-pressure side protective device
The low-pressure side arrester 310 is connected between step down side and ground together, the electromagnetism either transmitted from low-voltage cable
The electromagnetic interference traveling wave that interference traveling wave is still transmitted from high-tension cable, strong electromagnetic traveling wave therein are discharged into greatly through arrester
Ground, and light current magnetic disturbance traveling wave is reduced or is converted and subtract by high-pressure side protective device 120 and the low-pressure side protective device 320
Few impact to transformer.And at this time strong electromagnetic can only be discharged by arrester the earth, therefore even if ground resistance compared with
Energy release will not be influenced greatly.
Implement the transformer electromagnetic interference protecting system of the utility model, by the height for being separately positioned on high voltage side of transformer
Side protection equipment and the low-pressure side protection equipment of step down side are pressed, light current magnetic disturbance can be protected but also protect thunder and lightning etc.
Strong electromagnetic, and the resistance value of the ground resistance due to the grounded screen that can become larger, grounded screen manufacture and maintenance cost
It is relatively low.
Fig. 5 is the circuit diagram of the 5th embodiment of the transformer electromagnetic interference protecting system of the utility model.Fig. 5 is
It is illustrated by taking three-phase transformer as an example.As shown in figure 5, the transformer electromagnetic interference protecting system of the utility model includes setting
Equipment 100 is protected in the high-pressure side of the high voltage side of transformer of three-phase transformer 220 and is arranged on the low pressure of step down side
Protect equipment 300 in side.In the present embodiment, the high-pressure side protection equipment 100 includes being connected to the three-phase transformer 220
Protect equipment, the change for being connected to the three-phase transformer 220 in the first high-pressure side between first phase and ground of high voltage side of transformer
It protects equipment and is connected to the change of the three-phase transformer 220 in the second high-pressure side between on high-tension side second phase and ground of depressor
Third high-pressure side protection equipment between the on high-tension side third phase and ground of depressor.And the low-pressure side protection equipment 300 is connected to
Between first phase of the step down side of the three-phase transformer 220, the second phase, third phase and ground.
In the present embodiment, the first high-pressure side protection equipment includes the first end and transformer that are connected to high-tension cable
It the slow device 124 of electromagnetic wave traveling wave between on high-tension side first phase and is connected to lightning-arrest between the first end of high-tension cable and ground
Device 111.The second high-pressure side protection equipment includes being connected to the second end of high-tension cable and the second phase of high voltage side of transformer
Between the slow device 125 of electromagnetic wave traveling wave and the arrester 112 being connected between the second end of high-tension cable and ground.The third
High-pressure side protection equipment includes the electromagnetic wave row being connected between the third end of high-tension cable and the second phase of high voltage side of transformer
The slow device 126 of wave and the arrester 113 being connected between the second end of high-tension cable and ground.In the preferred implementation of the utility model
In example, the slow device 124,125 and 126 of electromagnetic wave traveling wave respectively constitutes high-pressure side protective device 120 shown in FIG. 1.
In the present embodiment, the low-pressure side protection equipment 300 includes slow 328,329,330 and of device of electromagnetic wave traveling wave
The 331 low-pressure side protective devices 320 formed and three groups of arresters 332,333,334.The of the slow device 328 of electromagnetic wave traveling wave
One end connects the first phase of the step down side of the three-phase transformer 220, the first end of second end connection low-voltage cable.Electricity
The first end of the slow device 329 of magnetic wave traveling wave connects the second phase of the step down side of the three-phase transformer 220, second end connects
Connect the second end of low-voltage cable.The transformer that the first end of the slow device 330 of electromagnetic wave traveling wave connects the three-phase transformer 220 is low
Press the third phase of side, the third end of second end connection low-voltage cable.The first end connection described three of the slow device 331 of electromagnetic wave traveling wave
The zero curve phase of the step down side of phase transformer 220, the 4th end of second end connection low-voltage cable.As shown in figure 5, three phase transformations
The shell of depressor 220 is grounded together with the 4th end of low-voltage cable.Arrester 332 is connected to the first end and ground of low-voltage cable
Between.Arrester 333 is connected between the second end of low-voltage cable and ground.Arrester 334 be connected to the third end of low-voltage cable with
Between ground.
The principle of the present embodiment is described as follows with reference to Fig. 5.
Whether the strong electromagnetic of thunder and lightning etc or light current magnetic disturbance are all with electromagnetic running wave on cable conductor
Mode is transmitted, electromagnetic running wave can prolong transformer high voltage cable or type low-voltage cable from being distally transmitted to transformer, it might even be possible to
It is transmitted simultaneously from high and low pressure side to transformer.
The electromagnetic interference traveling wave transmitted from certain high voltage cable can first pass around high-pressure side protection equipment.If
Electromagnetic interference traveling wave is strong electromagnetic, and the slow device meeting impedance of the electromagnetic wave traveling wave connected at this moment high-pressure side protection equipment is flowed through
The variation of its internal current, the effect brought are the rapid voltage for promoting transformer high-voltage side entrance.At this moment high voltage side of transformer
The arrester of entrance can be rapidly reached its startup voltage and be connected rapidly, and interference electromagnetic wave energy is released to the earth.If
Electromagnetic interference traveling wave is light current magnetic disturbance, and the startup voltage of arrester is not achieved, then the slow device of electromagnetic wave traveling wave can play inductance filter
The effect of wave device reduces the slope of interference waveform and part energy is converted to thermal dissipation, so as to reduce electromagnetic interference pair
The impact of transformer.
The electromagnetic interference traveling wave transmitted from certain type low-voltage cable can first pass around low-pressure side protection equipment.If
Electromagnetic interference traveling wave is strong electromagnetic, and the slow device meeting impedance of the electromagnetic wave traveling wave connected at this moment low-pressure side protection equipment is flowed through
The variation of its internal current, the effect brought are the rapid voltage for promoting transformer high-voltage side entrance.At this moment high voltage side of transformer
The arrester of entrance can be rapidly reached its startup voltage and be connected rapidly, and interference electromagnetic wave energy is released to the earth.If
Electromagnetic interference traveling wave is light current magnetic disturbance, and the startup voltage of arrester is not achieved, then the slow device of electromagnetic wave traveling wave can reduce interference
The slope of waveform, and part energy is converted to thermal dissipation, so as to reduce impact of the electromagnetic interference to transformer.
Why existing guard technology wishes that the ground resistance of grounded screen is the smaller the better, when being because of arrester conducting, electricity
Magnetic disturbance energy can be divided into 2 parallel shunt branches in arrester front end, flow to inside voltage device all the way, another way flow direction ground connection
Resistance.So ground resistance is smaller, the current energy for flowing to the earth is more, better to the protection of transformer, ground resistance
Play the role of adjusting interfering energy current drain ratio.
And after applying the transformer electromagnetic interference protecting system of the utility model, the energy of electromagnetic interference when arrester is connected
2 parallel shunt branches have been also divided into, but a branch for flowing to transformer is blocked, lightning current only has a Zhi Luxiang
The earth is released, and ground resistance at this time no longer takes on the effect for adjusting current drain ratio, becomes larger even if ground resistance
It can ensure interfering energy completely to greatly releasing.Therefore, using can appropriate amplifying transformer after the system of the utility model
The grounding resistance of earth mat, without influencing its protective capacities.
Fig. 6-8 shows the preferred slow device of electromagnetic wave traveling wave.As shown in fig. 6, the electromagnetic wave traveling wave of the utility model is stagnant
Slow device includes：Hollow conductive pipe 1, the magnet 4 being arranged on inside the hollow conductive pipe 1 are arranged on 1 He of hollow conductive pipe
With the first insulating sleeve 5 of the insulate magnet 4 and the hollow conductive pipe 1 between on the magnet 4, hollow led around described
Fulgurite 1 set magnetic sleeve pipe 3 and be arranged between the magnetic sleeve pipe 3 and the hollow conductive pipe 1 with insulate it is described in
Second insulating sleeve 2 of empty contact tube 1 and the magnetic sleeve pipe 3.
Fig. 7-8 further illustrates the preferred arrangement of hollow conductive pipe 1.As shown in figs 6-8, the hollow conductive pipe
1 can be formed by one section of hollow cylindrical metal tube milling, continuous helical slot 13 equidistantly be opened up on outer wall, so as to form spiral shell
Coil shape conductor structure.Forming this structure feature can be more advantageous to increasing the intrinsic inductance amount of hollow conductive pipe 1, so as to carry
Impedance of the height to electromagnetic running wave.And using the hollow conductive pipe 1 of this structure as electric conductor, sectional area is easy to do greatly,
It is highly suitable for the application scenario of high current.Certainly in other preferred embodiments of the utility model, which also may be used
It is set with Unequal distance.In addition, those skilled in the art know, it may be used that other any conductive materials constructions are described hollow to lead
Fulgurite 1.In addition, in other preferred embodiments of the utility model, the outer wall of the hollow conductive pipe 1 can be it is smooth,
Equidistant or Unequal distance setting helical raised can be set to form hollow worm gear on it.
As shown in fig. 6, the magnet 4 is preferably the bar magnet being threaded through in the hollow conductive pipe 1.The hollow conductive pipe
1 11 center setting center through hole 14 of end walls passes through for the bar magnet.It is also enclosed in the end walls 11 of the hollow conductive pipe 1
Multiple periphery through-holes 12 are placed equidistant with around center through hole 14.Certainly, in the simplification embodiment of the utility model, it is convenient to omit this
A little peripheries through-hole 12, and magnet 4 can be arranged in any other manner inside the hollow conductive pipe 1, can be
Any shape.In the utility model, it is preferred to use strong bar magnet is as magnet 4.
As shown in fig. 6, first insulating sleeve 5 can be set on the magnet 4 with the magnet 4 and described of insulating
Hollow conductive pipe 1.In other preferred embodiments of the utility model, other modes may be used, for example wrap up, surround, it is close
Other any modes such as envelope keep apart magnet 4 and hollow conductive pipe 1.It is preferred that using the insulating materials of high-k, example
Such as common plastics of the dielectric constant 2~4 or so, dielectric constant makes first insulation sleeve in 6~8 or so ceramic material
Pipe 5.It is, of course, also possible to using the material with other dielectric constants, those skilled in the art can carry out according to actual conditions
Selection.
Further as shown in fig. 6, the second insulation tube 2 can be equally set in the hollow conductive pipe 1 with described in insulation
Hollow conductive pipe 1 and the magnetic sleeve pipe 3.In other preferred embodiments of the utility model, other modes may be used, than
It such as package, surround, other any modes such as sealing are by the hollow conductive pipe 1 and the magnetic sleeve pipe 3.It is preferred that using high dielectric
The insulating materials of constant, such as dielectric constant is in 2~4 or so common plastics, ceramic material of the dielectric constant 6~8 or so
To make second insulating sleeve 2.It is, of course, also possible to using the material with other dielectric constants, those skilled in the art can
To be selected according to actual conditions.
Further as shown in fig. 6, magnetic sleeve pipe 3 is preferably to be located at the cylindrical sleeve except the second insulation tube 2.When
So, in other preferred embodiments of the utility model, the magnetic sleeve pipe 3 can also use other any shapes.It is preferred that it adopts
The magnetic sleeve pipe 3, art technology are made with the material of high magnetic permeability, such as amorphous, nanocrystalline, ferrite, iron powder core material
Personnel can specifically be selected according to actual conditions.
Further as shown in fig. 6, in the present embodiment, further including and being arranged on 1 both ends of hollow conductive pipe so as to fixed
Whole equipment and the fixedly connected part 6 for connecting it with external interface.It certainly, can in the simplification embodiment of the utility model
To omit the fixedly connected part 6.As shown in fig. 6, the fixedly connected part includes annular insulation Jie piece 62 and conductive fixed cover 61.It should
Annular insulation Jie piece 62 is for the hollow conductive pipe 1 that insulate with the magnetic sleeve pipe 3 the two to be prevented to be electrically connected.The annular is exhausted
Edge Jie piece 62 can be made of any insulating materials.Certainly, in the other embodiment of the utility model, other can also be used
Insulation Jie's piece of shape, as long as being shaped to be adapted to the hollow conductive pipe 1 and the magnetic sleeve pipe 3, therefore can be exhausted
Hollow conductive pipe 1 described in edge and the magnetic sleeve pipe 3 are both to prevent from being electrically connected.The conduction fixed cover 61 is fixed on institute
Magnetic sleeve pipe 3 is stated to fasten whole equipment, and be electrically connected with external interface convenient for hollow conductive pipe 1.Conductive fixed cover 61 is preferred
The metal connecting sheet that multiple through-holes are set may be used.The multiple through-hole can be adapted to each through-hole in hollow conductive pipe 1.
The above-mentioned slow device of electromagnetic wave traveling wave of the utility model passes through magnet+insulating sleeve+conductor+insulating sleeve+magnetism
The composite construction of casing, while the dielectric constant and relative permeability of the conductor surrounding medium of electromagnetic wave traveling wave are improved, it can drop
Low electromagnetic wave traveling wave speed and waveform steepness.
Below in conjunction with the preferred embodiment shown in Fig. 6-7, to the principle of the slow device of electromagnetic wave traveling wave of the utility model
It is described as follows：
Spread speed v of the electromagnetic wave traveling wave in conducting wire be：
In above formula：
C is the light velocity, c=3 × 108Meter per second.
εrRelative dielectric constant for conducting wire surrounding medium.
μrRelative permeability for conducting wire surrounding medium.
By above formula it is recognised that spread speed of the electromagnetic wave traveling wave in conducting wire, material, length, sectional area with conducting wire,
Inductance, distribution capacity etc. are irrelevant, only it is related with the characteristic of the dielectric around conducting wire, more particularly only with insulation
The relative dielectric constant ε of mediumrWith relative permeability μrIt is related.
If traveling wave is propagated on overhead conducting wire, dielectric is air around conducting wire, the opposite dielectric of air
Constant εr≈ 1, relative permeability μr≈ 1, therefore v ≈ c, i.e. the spread speed of traveling wave is basically the light velocity.If it is intended to it reduces
Spread speed of the traveling wave in certain section of conductor can also may be used reaching by way of replacing the dielectric of high-k ε r
Reached in a manner of relativepermeabilityμr around conductor by improving.
If we in addition to want reduce traveling wave spread speed, also want to reduce traveling-wave waveform steepness.At this moment will try
Increase the impedance in transmission path.
So, wave impedance Z of the electromagnetic wave traveling wave in conducting wire is：
ε in above formula0--- permittivity of vacuum；
εr--- relative dielectric constant；
μ0--- space permeability；
μr--- relative permeability；
hd--- conducting wire average height over the ground；
R --- wire radius.
From the above equation, we can see that wave impedance Z is not only related with the relative dielectric constant ε r of dielectric and relativepermeabilityμr, also
Related with the distribution character of conductor, the radius r (circular cross-section conductor) of conductor, the sectional area even position of conductor over the ground can also produce
It is raw to influence.
It is excessive that this appears to variable, but from the point of view of engineering viewpoint, since traveling wave can be used as propagation by conductor
Path, then the presence of inevitable the having determined property of conducting wire, then its parameter whether sectional area, radius and the distance on ground
Etc. be all to determine, too big variation will not be generated, this is determined by the natural quality of object.
It so, can be wire radius r, conducting wire average height h over the ground in our practical engineering applicationsdEtc. parameters regard one as
A constant is handled.At this moment ε0、μ0、hd, r be all constant, we can be replaced with a constant coefficient K.
It enables
So wave impedance formula can be simplified to：
It therefore deduces that：In the case where conductor has determined, influence the characteristic of wave impedance during traveling wave also only and
The relative dielectric constant ε of dielectricrWith relative permeability μrIt is related.
By being analyzed above it is found that a kind of slow device of electromagnetic wave traveling wave can be constructed, wherein providing electromagnetism by one section of conductor
Wave traveling wave access, medium around conductor can carry out traveling wave wave by adjusting relative dielectric constant ε r and relativepermeabilityμr
The adjustment of speed and wave impedance.
ByAs long as it is found that selection εr=4 dielectric, even if working as μrWhen=1, v=0.5c also can obtain
The speed of electromagnetic running wave can be namely reduced to the half of the light velocity.And by increasing μrNumerical value can play the work of bigger
With especially present new material such as amorphous etc. can be μrAccomplish more than 80000~100000.But actually it is difficult to find both
Insulation performance well again have high magnetic permeability insulating materials because the material for having magnetic conductivity be typically all metal or comprising metal into
Point.
ByIt is found that and by increasing μrNumerical value can greatly improve wave resistance antiatherosclerotic effect, although we in order to
It reduces velocity of wave and improves ε simultaneouslyrNumerical value, but εrUsual very little, the dielectric constant of general solid is all units, and magnetic
Conductance μrCan be very big, it is possible thereby to ignore εrIncreased influence.
Therefore, the utility model constructs such a slow device of electromagnetic wave traveling wave, including：Hollow conductive pipe 1 is arranged on
Magnet 4 inside the hollow conductive pipe 1, with the magnetic that insulate between being arranged on the hollow conductive pipe 1 and the magnet 4
First insulating sleeve 5 of body 4 and the hollow conductive pipe 1, around the magnetic sleeve pipe 3, Yi Jishe of the hollow conductive pipe 1 setting
It puts between the magnetic sleeve pipe 3 and the hollow conductive pipe 1 with the insulate hollow conductive pipe 1 and the magnetic sleeve pipe 3
Second insulating sleeve 2.
Tectonic sieving is carried out by using the pattern of such complex media, is insulated by one layer of insulating sleeve, then
An additional magnetic sleeve pipe provides high μ r, and two media is used cooperatively, that is, significantly reduces velocity of wave, and be added significantly to wave resistance
It is anti-.It greatly improves the efficiency.
The utility model is improved simultaneously by the composite construction of magnet+insulating sleeve+conductor+insulating sleeve+magnetic sleeve pipe
The dielectric constant and relative permeability of the conductor surrounding medium of electromagnetic wave traveling wave, the velocity of wave that can make electromagnetic running wave are new in this practicality
The part of the light velocity is reduced in the slow device of electromagnetic wave traveling wave of type to 1/tens, and substantially gentle electromagnetic running wave
Waveform steepness.
The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this
All any modification, equivalent and improvement made within the spirit and principle of utility model etc., should be included in the utility model
Protection domain within.
Claims (10)
1. a kind of transformer electromagnetic interference protecting system, which is characterized in that including：The high-pressure side for being arranged on high voltage side of transformer is protected
Shield equipment and the low-pressure side protection equipment for being arranged on step down side；Wherein described high-pressure side protection equipment includes being connected to
High-pressure side arrester between high-tension cable and ground and it is connected to high-tension cable and the high-pressure side of the high voltage side of transformer is prevented
Protection unit, the low-pressure side protection equipment include being connected to the low-pressure side arrester between low-voltage cable and ground and being connected to low
The low-pressure side protective device of voltage cable and the step down side.
2. transformer electromagnetic interference protecting system according to claim 1, which is characterized in that the high-pressure side protective device
And/or the low-pressure side protective device includes differential mode inductors.
3. transformer electromagnetic interference protecting system according to claim 2, which is characterized in that the high-pressure side protective device
And/or the low-pressure side protective device further comprises the common-mode inductor connected with the differential mode inductors.
4. transformer electromagnetic interference protecting system according to claim 3, which is characterized in that the differential mode inductors include
High frequency magnetic core and coil；The common-mode inductor includes at least two co-mode coils and the height being arranged between the co-mode coil
Frequency magnet ring.
5. transformer electromagnetic interference protecting system according to claim 1, which is characterized in that the high-pressure side protective device
And/or the low-pressure side protection equipment is the slow device of electromagnetic wave traveling wave, the slow device of electromagnetic wave traveling wave includes：Hollow conductive
The magnet managed, be arranged on inside the hollow conductive pipe is arranged between the hollow conductive pipe and the magnet to insulate
Magnet and the first insulating sleeve of the hollow conductive pipe are stated, around the magnetic sleeve pipe of hollow conductive pipe setting, Yi Jishe
It puts between the magnetic sleeve pipe and the hollow conductive pipe to insulate the second of the hollow conductive pipe and the magnetic sleeve pipe
Insulating sleeve.
6. transformer electromagnetic interference protecting system according to claim 5, which is characterized in that the hollow conductive pipe is outer
The cylindrical metal tube of continuous helical slot is opened up on wall.
7. transformer electromagnetic interference protecting system according to claim 6, which is characterized in that the magnet is is threaded through
State the bar magnet in the center of cylindrical metal tube, the end walls center setting of the cylindrical metal tube for the bar magnet by the
One through-hole.
8. transformer electromagnetic interference protecting system according to claim 7, which is characterized in that the cylindrical metal tube
In end walls multiple second through-holes are placed equidistant with around the first through hole.
9. transformer electromagnetic interference protecting system according to claim 5, which is characterized in that further comprise being arranged on institute
State the fixedly connected part at hollow conductive pipe both ends；The fixedly connected part includes being set in the hollow conductive pipe both ends to insulate
Annular insulation Jie's piece of the hollow conductive pipe and the magnetic sleeve pipe and the conduction being fixed in the magnetic sleeve pipe are fixed
Lid；Multiple third through-holes are set on the outer wall of the conduction fixed cover.
10. the transformer electromagnetic interference protecting system according to any claim in claim 1-9, which is characterized in that
The transformer be single-phase transformer or three-phase transformer, the earthing of casing of the transformer.
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| CN201721323047.7U CN207542059U (en) | 2017-10-12 | 2017-10-12 | A kind of transformer electromagnetic interference protecting system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201721323047.7U CN207542059U (en) | 2017-10-12 | 2017-10-12 | A kind of transformer electromagnetic interference protecting system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107578901A (en) * | 2017-10-12 | 2018-01-12 | 深圳市创仕达电子有限公司 | A kind of transformer electromagnetic interference protecting system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107578901A (en) * | 2017-10-12 | 2018-01-12 | 深圳市创仕达电子有限公司 | A kind of transformer electromagnetic interference protecting system |
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