CN107196494A - Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system - Google Patents
Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system Download PDFInfo
- Publication number
- CN107196494A CN107196494A CN201710457273.2A CN201710457273A CN107196494A CN 107196494 A CN107196494 A CN 107196494A CN 201710457273 A CN201710457273 A CN 201710457273A CN 107196494 A CN107196494 A CN 107196494A
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- electric capacity
- leakage current
- current absorption
- resistance
- power network
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- 238000010521 absorption reaction Methods 0.000 title claims abstract description 57
- 230000001681 protective effect Effects 0.000 claims abstract description 6
- 238000004804 winding Methods 0.000 claims description 5
- 230000005611 electricity Effects 0.000 claims description 4
- 239000003990 capacitor Substances 0.000 claims description 2
- 239000010409 thin film Substances 0.000 claims 1
- 238000005516 engineering process Methods 0.000 abstract description 3
- 238000012360 testing method Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
- H02M1/34—Snubber circuits
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
- H02M1/34—Snubber circuits
- H02M1/348—Passive dissipative snubbers
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The present invention relates to converter technology field; disclose the leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system; it is made up of the common mode inductance and leakage current Absorption Capacitance of generation common code impedance, wherein leakage current absorption plant one end is connected with earth leakage protective device, and one end is connected with frequency converter; one end is grounded; the leakage current for flowing through earth leakage circuit-breaker can be reduced by the present invention, the problem of false tripping is protected in leakage is solved, and it is simple to operate in realization; occupy little space, cost is low.
Description
Technical field
The present invention relates to converter technology field, leakage current absorption plant and change in more particularly to a kind of frequency convertor system
Frequency device application system.
Background technology
With voltage-source type pulse width modulation (PWM, Pulse Width Modulation) frequency converter combination property
Improve constantly, its application is more and more extensive.Wherein there is also some significant negative effects, for example, opened equipped with earth leakage protective
In the power-supply system for closing (referred to as leakage is protected), occur that tripping operation is protected in power network side leakage when frequency converter is run.The reason for tripping operation is to become
The high frequency common mode voltage that frequency device is produced produces common mode current by the distribution capacity of motor terminals over the ground, and change is flowed back to by ground system
Frequency device front end power network, when common mode current exceedes the earth leakage circuit-breaker trip threshold that grid side is configured, earth leakage circuit-breaker meeting
Jump.
For the problem of tripping operation is protected in leakage caused by frequency conversion speed-adjusting system, some solutions are in inverter output terminal increase
Active filter, to eliminate common mode current.This scheme can tackle the problem at its root, but cost is high, and design is complicated, no
Can be commonly used.
The content of the invention
The purpose of embodiment of the present invention is to provide leakage current absorption plant and frequency converter in a kind of frequency convertor system
The scheme of application system, reduces the common mode current for flowing through earth leakage circuit-breaker, so that the problem of solving Lou to protect false tripping.
In order to solve the above technical problems, the leakage current that embodiments of the present invention are provided in a kind of frequency convertor system absorbs
Device, the leakage current absorption plant includes the common mode inductance and leakage current Absorption Capacitance for producing common code impedance, wherein described common
Mould inductance one end is connected with earth leakage protective device, and the other end is connected with frequency converter and the leakage current Absorption Capacitance respectively；It is described
Leakage current Absorption Capacitance one end is connected and frequency converter connection with the common mode inductance respectively, other end ground connection.
Compared with the prior art for the mode of the extra wave filter of middle increase, the present invention is by setting common mode inductance can be
EMI (electromagnetic interference), which is filtered, handles and produces common code impedance and increase common code impedance, can by leakage current Absorption Capacitance
To absorb EMI (electromagnetic interference) while changing common mode current flow cycle, so as to reduce the common mode electricity for flowing through earth leakage circuit-breaker
Stream, can reduce cost and system complexity, reduce the device space, can realize more common application.
It is preferred that, the common mode inductance is realized using input triple line winding magnetic core or three-phase alternating current reactance device.Work as use
When inputting triple line winding magnetic core, the magnetic core is one kind in annular, rectangle, E shapes, tank shape, RM shapes or EP shapes, winding side
Formula using packet coiling or triple line and around.The embodiment of different common mode inductances, enhancing can be selected according to actual conditions
Systematic difference versatility.
It is preferred that, leakage current absorption plant also include electric capacity discharge resistance, described electric capacity discharge resistance one end respectively with institute
State common mode inductance connection, leakage current Absorption Capacitance and frequency converter connection, other end ground connection.So can be preferably to circuit system
Protected, improve the stability and reliability of system.
Embodiments of the present invention additionally provide a kind of application of frequency converter system, the input power network of the application of frequency converter system
Comprising three phase network and single-phase power network, voltage class includes 690V grades, 400V grades, 200V grades, and the system includes foregoing electric leakage
Flow absorption plant.
To sum up, the present invention building and verifying by the analysis to leakage current loop and equivalent-circuit model, proposes one
The scheme for changing common mode current coupling circuit is planted, the common mode current for flowing through earth leakage circuit-breaker can be reduced, so as to solve Lou to protect
It is the problem of false tripping, simple to operate in realization, occupy little space, cost is low.
Brief description of the drawings
Fig. 1 is flow cycle equivalent model figure in the present embodiment；
Fig. 2 is leakage current absorption plant structure chart in the present embodiment；
Fig. 3 is another structure chart of leakage current absorption plant in the present embodiment；
Fig. 4 is another structure chart of leakage current absorption plant in the present embodiment；
Fig. 5 is another structure chart of leakage current absorption plant in the present embodiment；
Fig. 6 is the frequency convertor system figure added with leakage current absorption plant in the present embodiment.
Embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with each reality of the accompanying drawing to the present invention
The mode of applying is explained in detail.However, it will be understood by those skilled in the art that in each embodiment of the invention,
In order that reader more fully understands the application and proposes many ins and outs.But, even if without these ins and outs and base
Many variations and modification in following embodiment, can also realize each claim of the application technical side claimed
Case.
The first embodiment of the present invention is related to the leakage current absorption plant in a kind of frequency convertor system.It is as shown in Figure 1
The schematic equivalent circuit of the leakage current absorption plant.
With reference to shown in Fig. 1, Fig. 6, the leakage current absorption plant 11 in frequency convertor system, wherein, the leakage current absorbs dress
Putting 11 includes common mode inductance 12, leakage current Absorption Capacitance 13, and wherein one end of common mode inductance 12 is connected with earth leakage protective device 14, separately
One end is connected with frequency converter 23 and leakage current Absorption Capacitance 13 respectively；Described one end of leakage current Absorption Capacitance 13 respectively with it is described common
Mould inductance 12 is connected and frequency converter 23 is connected, other end ground connection.
In one embodiment, common mode inductance is using input triple line and rich magnet ring scheme, inductance value L=AL*N2,
AL is magnet ring initial inductance value, and N is the number of turn of wound around coil.In another embodiment, common mode inductance can also be used
Three-phase alternating current reactance device.
When using input triple line winding magnetic core, the magnetic core is annular, rectangle, E shapes, tank shape, RM shapes or EP shapes
In one kind, canoe using packet coiling or triple line and around.It should be noted that common mode inductance has a variety of embodiment party
Formula, herein by way of example only.
In one embodiment, leakage current absorption plant as shown in Figure 2, wherein, leakage current Absorption Capacitance is by first
Electric capacity C1, the second electric capacity C2, the 3rd electric capacity C3 electric capacity composition, first electric capacity C1 one end are connected with the first power network L1, the other end
It is connected and is grounded with the second electric capacity C2, the 3rd electric capacity C3；Second electric capacity C2 one end is connected with the second power network L2, the other end and
First electric capacity C1, the 3rd electric capacity C3 are connected and are grounded；3rd electric capacity C3 one end is connected with the 3rd power network L3, the other end and
One electric capacity C1, the second electric capacity C2 are connected and are grounded.In a detailed embodiment, the first electric capacity C1, the second electric capacity C2,
Three electric capacity C3 are X safety electric capacity, and this is only to give one kind preferred embodiment, it should be appreciated that when using other classes
In the case that the electric capacity of type also can reach identical purpose, the other types of electric capacity should also be included in the protection of the application
In the range of.
In another embodiment, as shown in figure 3, leakage current Absorption Capacitance is by the first electric capacity C1, the second electric capacity C2,
Three electric capacity C3, the 4th electric capacity C4 are constituted, and first electric capacity C1 one end is connected with the first power network L1, the other end respectively with the second electric capacity
C2, the 3rd electric capacity C3, the 4th electric capacity C4 are connected；Second electric capacity C2 one end is connected with the second power network L2, the other end and first
Electric capacity C1, the 3rd electric capacity C3, the 4th electric capacity C4 are connected；3rd electric capacity C3 one end is connected with the 3rd power network L3, the other end point
Not be connected with the first electric capacity C1, the second electric capacity C2, the 4th electric capacity C4；4th electric capacity C4 one end is connected with power network PE (i.e. ground wire)
Connect, the other end is connected with the first electric capacity C1, the second electric capacity C2, the 3rd electric capacity C3 respectively.In a detailed embodiment,
One electric capacity C1, the second electric capacity C2, the 3rd electric capacity C3 are X safety electric capacity, and the 4th electric capacity C4 is Y safety electric capacity, and this only gives
One kind is preferred embodiment, it should be appreciated that can also reach the feelings of identical purpose when using other types of electric capacity
Under condition, the other types of electric capacity should be also included in the protection domain of the application.
In one embodiment, as shown in figure 4, also including electric capacity discharge resistance 14 in leakage current absorption plant, electricity
The one end of discharge capacitor resistance 14 is connected with the common mode inductance 12 respectively, leakage current Absorption Capacitance 13 and frequency converter 23 are connected, another
End ground connection.
In a kind of embodiment, as shown in figure 5, electric capacity discharge resistance is by first resistor R1, second resistance R2,
Three resistance R3, the 4th resistance R4 are constituted.First resistor R1 one end is connected with the first power network L1, and the other end is respectively and second resistance
R2,3rd resistor R3, the 4th resistance R4 are connected.Second resistance R2 one end is connected with the second power network L2, the other end and first
Resistance R1,3rd resistor R3, the 4th resistance R4 are connected.3rd resistor R3 one end is connected with the 3rd power network L3, the other end point
Not be connected with first resistor R1, second resistance R2, the 4th resistance R4.4th resistance R4 one end is connected with power network PE (i.e. ground wire)
Connect, the other end and the first electric capacity C1, the second electric capacity C2, the 3rd electric capacity C3, the 4th electric capacity C4, first resistor R1, second resistance R2,
3rd resistor R3 is connected.
It should be noted that Fig. 1 show the schematic equivalent circuit of leakage current absorption plant, the schematic equivalent circuit
The principle of equal effects be：The high frequency common mode voltage that frequency converter is produced, common mode current is produced by the distribution capacity of motor terminals over the ground,
Distribution capacity is determined the high frequency common mode voltage and motor side that frequency converter is produced by system over the ground, can be with equivalent for fixed system
For current source, frequency converter front end power network is flowed back to by ground system, loop is formed.Wherein, the production of three-phase and single-phase common mode current
Life reason is the same.
In the schematic equivalent circuit shown in Fig. 1, power transformer leakage inductance and common mode inductance series equivalent are Rl, and and
Leakage current Absorption Capacitance Cf is in parallel.From Kirchhoff's law：
Release
Wherein, RlFor common-mode resistance, RcFor absorption resistance；IlFor common mode current, IcTo absorb electric current.
The leakage current Icm and formula 2 produced according to actual test motor side, by the inductance value and the absorption that adjust common mode inductance
The capacitance of electric capacity, it is possible to the drain current limit of earth leakage circuit-breaker will be flowed through in the range of trip threshold.
Second embodiment of the present invention is related to a kind of application of frequency converter system, structure such as Fig. 6 institutes of the frequency convertor system
Show.In the frequency convertor system, including：Leakage current absorption plant 11, the frequency converter 23 of earth leakage protective device 14, motor 24.The frequency conversion
The input power network of device application system includes three phase network and single-phase power network, and voltage class includes 690V grades, 400V grades, 200V grades.
In one embodiment, in the frequency convertor system, one of common mode inductance 12 in leakage current absorption plant 11
End is connected with frequency converter 23；One end of leakage current Absorption Capacitance 13 in leakage current absorption plant 11 is connected with frequency converter 23, another
End ground connection.
The effect that the present invention can reach is illustrated below by way of a specific example.
Assume in the example according to Fig. 6 added with, carry out actual effect test it is as follows：B ammeters testing of electric motors 24
The common mode current that side is produced, actual measurement is about 290mA.
It is 100mA to assume that trip threshold is protected in the leakage of frequency converter front end in the example, when frequency converter works, it is desirable to ammeter
The electric current of A tests is less than 100mA.The common mode inductance and Absorption Capacitance of leakage current absorption plant are configured according to formula, is selected here
MnZn magnetic makes common mode inductance, and Absorption Capacitance selects 1uf safety electric capacity.According to formula theoretical calculation, common mode current at ammeter A
For 56mA, actual test value is 62mA.
Consider the limitation of model and the evaluated error of parasitic parameter, device proposed by the present invention is in theoretical electric current
Value is consistent in trend with measured current value, and therefore, scheme proposed by the present invention realizes upper simple to operate, space-consuming
Small, cost is low, it is possible to effective to solve the problem of false tripping is protected in leakage.
It will be understood by those skilled in the art that the respective embodiments described above are to realize the specific embodiment of the present invention,
And in actual applications, can to it, various changes can be made in the form and details, without departing from the spirit and scope of the present invention.
Claims (10)
1. the leakage current absorption plant in a kind of frequency convertor system, it is characterised in that the leakage current absorption plant includes producing
The common mode inductance and leakage current Absorption Capacitance of common code impedance, wherein described common mode inductance one end is connected with earth leakage protective device, separately
One end is connected with frequency converter and the leakage current Absorption Capacitance respectively；Described leakage current Absorption Capacitance one end and the common mode inductance
With frequency converter connection, other end ground connection.
2. leakage current absorption plant according to claim 1, it is characterised in that the common mode inductance is using input triple line
Wind magnetic core or three-phase alternating current reactance device is realized.
3. leakage current absorption plant according to claim 2, it is characterised in that when using input triple line winding magnetic core
When, the magnetic core is one kind in annular, rectangle, E shapes, tank shape, RM shapes or EP shapes, and canoe is using packet coiling or three
Phase line and around.
4. leakage current absorption plant according to claim 1 or 2, it is characterised in that the leakage current Absorption Capacitance includes
First electric capacity, the second electric capacity and the 3rd electric capacity, wherein, first electric capacity one end is connected with the first power network, and the other end is respectively with second
Electric capacity, the 3rd capacitance connection are simultaneously grounded；Second electric capacity one end is connected with the second power network, the other end respectively with the first electric capacity, the 3rd
Capacitance connection is simultaneously grounded；3rd electric capacity one end is connected with the 3rd power network, the other end respectively with the first electric capacity, the second capacitance connection simultaneously
Ground connection.
5. leakage current absorption plant according to claim 4, it is characterised in that the first electric capacity, the second electric capacity, the 3rd electric capacity
For safety electric capacity or thin-film capacitor.
6. leakage current absorption plant according to claim 1 or 2, it is characterised in that the leakage current Absorption Capacitance includes
First electric capacity, the second electric capacity, the 3rd electric capacity and the 4th electric capacity, wherein, first electric capacity one end is connected with the first power network, the other end point
Not with the second electric capacity, the 3rd electric capacity, the 4th capacitance connection；Second electric capacity one end is connected with the second power network, and the other end is respectively with
One electric capacity, the 3rd electric capacity, the 4th capacitance connection；3rd electric capacity one end is connected with the 3rd power network, the other end respectively with the first electric capacity,
Second electric capacity, the 4th capacitance connection；4th electric capacity one end be grounded, the other end respectively with the second electric capacity, the 3rd electric capacity, the 4th electric capacity
Connection.
7. the leakage current absorption plant in frequency convertor system according to claim 6, the first electric capacity, the second electric capacity, the 3rd
Electric capacity is X safety electric capacity, and the 4th electric capacity is Y safety electric capacity.
8. the leakage current absorption plant in frequency convertor system according to claim 1, it is characterised in that the leakage current is inhaled
Receiving apparatus also includes electric capacity discharge resistance, and described electric capacity discharge resistance one end is connected with the common mode inductance respectively, leakage current is inhaled
Receive electric capacity and frequency converter connection, other end ground connection.
9. the leakage current absorption plant in frequency convertor system according to claim 8, it is characterised in that the electric capacity electric discharge
Resistance includes first resistor, second resistance, 3rd resistor and the 4th resistance, wherein, first resistor one end is connected with the first power network,
The other end is connected with second resistance, 3rd resistor, the 4th resistance respectively；Second resistance one end is connected with the second power network, the other end
It is connected respectively with first resistor, 3rd resistor, the 4th resistance；3rd resistor one end is connected with the 3rd power network, the other end respectively with
First resistor, second resistance, the connection of the 4th resistance；4th resistance one end be grounded, the other end respectively with first resistor, the 3rd electricity
Resistance, the 4th resistance, the first electric capacity, the second electric capacity, the 3rd electric capacity, the 4th capacitance connection.
10. a kind of application of frequency converter system, the input power network of the application of frequency converter system includes three phase network and single-phase power network, electricity
Grade is pressed to include 690V grades, 400V grades, 200V grades, it is characterised in that to be inhaled including the leakage current described in claim any one of 1-8
Receiving apparatus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710457273.2A CN107196494A (en) | 2017-06-16 | 2017-06-16 | Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710457273.2A CN107196494A (en) | 2017-06-16 | 2017-06-16 | Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system |
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| CN107196494A true CN107196494A (en) | 2017-09-22 |
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| CN201710457273.2A Pending CN107196494A (en) | 2017-06-16 | 2017-06-16 | Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020070821A1 (en) * | 2000-12-07 | 2002-06-13 | Henry Moller | RFI filter for a frequency converter |
| CN1402417A (en) * | 2001-08-21 | 2003-03-12 | 株式会社日立制作所 | Power current transformer |
| CN102386760A (en) * | 2011-11-22 | 2012-03-21 | 中冶南方（武汉）自动化有限公司 | Frequency converter multistage EMI (electromagnetic interference) filter circuit |
| CN202550866U (en) * | 2012-03-22 | 2012-11-21 | 深圳市英威腾电气股份有限公司 | Electromagnetic interference filter circuit and device with same |
| CN207074954U (en) * | 2017-06-16 | 2018-03-06 | 上海辛格林纳新时达电机有限公司 | Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system |
-
2017
- 2017-06-16 CN CN201710457273.2A patent/CN107196494A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020070821A1 (en) * | 2000-12-07 | 2002-06-13 | Henry Moller | RFI filter for a frequency converter |
| CN1402417A (en) * | 2001-08-21 | 2003-03-12 | 株式会社日立制作所 | Power current transformer |
| CN102386760A (en) * | 2011-11-22 | 2012-03-21 | 中冶南方（武汉）自动化有限公司 | Frequency converter multistage EMI (electromagnetic interference) filter circuit |
| CN202550866U (en) * | 2012-03-22 | 2012-11-21 | 深圳市英威腾电气股份有限公司 | Electromagnetic interference filter circuit and device with same |
| CN207074954U (en) * | 2017-06-16 | 2018-03-06 | 上海辛格林纳新时达电机有限公司 | Leakage current absorption plant and application of frequency converter system in a kind of frequency convertor system |
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Application publication date: 20170922 |