CN205212696U - Passive suppression device of PWM inverter motor actuating system electromagnetic interference I/O - Google Patents
Passive suppression device of PWM inverter motor actuating system electromagnetic interference I/O Download PDFInfo
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- CN205212696U CN205212696U CN201521097898.5U CN201521097898U CN205212696U CN 205212696 U CN205212696 U CN 205212696U CN 201521097898 U CN201521097898 U CN 201521097898U CN 205212696 U CN205212696 U CN 205212696U
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- filter
- filter circuit
- inductance
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Abstract
Passive suppression device of PWM inverter motor actuating system electromagnetic interference I/O, it relates to the passive suppression device of PWM converter motor drive system. The utility model discloses a solve PWM inverter motor actuating system among the prior art to have the electromagnetic interference suppressing effect that produces to the system poor, lead to the fact the problem of electric wire netting pollution easily. The utility model discloses a three -phase AC power supply who connects gradually, the inlet side wave filter, a rectification circuit, first direct current BUS capacitors, second direct current BUS capacitors, inverter circuit, the outlet side wave filter is cable and motor in excess supply, first direct current BUS capacitors and second direct current BUS capacitors series connection back connect on the dc bus of rectifier circuit outlet side, the tie point of connecting first direct current BUS capacitors and second direct current BUS capacitors behind the output of the output connection outlet side wave filter of inlet side wave filter. The utility model discloses a restrain electromagnetic interference in the PWM inverter motor actuating system etc. Make the conduction electromagnetic interference of system not exceed standard.
Description
Technical field
The utility model relates to the passive restraining device of PWM frequency converter motor driven systems, is specifically related to the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O, belongs to the field of electromagnetic compatibility technical field of PWM variable-frequency motor drive system.
Background technology
At present, PWM frequency converter is applied more and more extensive in industry, business and civil systems, and such as motor driven systems just generally adopts PWM technology.In three-phase PWM application of frequency converter, due to the asymmetry that pulse exports, in system, certainly exist common-mode voltage.Research shows, the high frequency common mode voltage that PWM frequency converter produces and larger du/dt bring many negative effects to system, as shaft voltage, shaft current, common mode leakage current, motor terminals overvoltage (motor and PWM frequency converter adopt long cable to be connected cause) and electromagnetic interference etc.
Electromagnetic interference has two kinds of forms: conduction and radiation.The Conducted Electromagnetic Interference that frequency converter produces occurs with the common mode of voltage or electric current and differential mode form, and it is divided into differential mode interference and common mode disturbances.Differential mode interference to refer to by phase line and center line form interference signal in loop; Common mode disturbances then to refer to by phase line or center line and ground wire form interference signal in loop.The main distinction of common and different mode is that common-mode signal forms loop with passing through, and difference mode signal is without ground.For frequency converter, the conducted interference in most cases produced is based on common mode disturbances, and common mode current flows through the earth forms loop, the earth will form antenna effect, bring serious electromagnetic interference to other equipment, this harm that common mode disturbances is caused is far longer than the harm that differential mode interference causes.Therefore common mode disturbances seems particularly important in the electromagnetic Compatibility Design of PWM variable-frequency motor drive system, and this common mode current is the leakage current of system.Scholars has carried out the research work of theory and application technology in succession round these 3 aspects of the interference source of electric system, route of transmission and sensitive equipment for this reason, and achieves certain achievement.Comprise two classes generally: a class reduces the interference strength of interference source; Another kind of is the propagation being suppressed interference by filtering.
In addition, due to the compulsory execution of electromagnetic compatibility standard, the electromagnetic interference that PWM variable-frequency motor drive system produces also more and more is subject to people's attention.In order to reach the requirement of the world/domestic electromagnetic compatibility standard, certain measure must be taked to carry out electromagnetic interference suppression.The electromagnetic interference inhibition that existing PWM variable-frequency motor drive system produces for system is poor, easily causes electric network pollution.
Utility model content
The purpose of this utility model is poor for the electromagnetic interference inhibition of system generation in order to solve PWM variable-frequency motor drive system of the prior art existence, easily causes the problem of electric network pollution.
The technical solution of the utility model is: the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O, comprise the three-phase alternating-current supply connected successively, input side filter, rectifying device, first dc-link capacitance, second dc-link capacitance, inverter, outlet side filter long cable and motor, be attempted by the DC bus of rectifying device outlet side after first dc-link capacitance and the series connection of the second dc-link capacitance, the tie point of the first dc-link capacitance and the second dc-link capacitance is connected after the output of the output connection outlet side filter of described input side filter.
Described input side filter comprises three-phase input end, three inductance and a RC filter circuit, the three-phase input end of input side filter connects the ac input end of rectifying device respectively by inductance, between the three-phase input end that the three-phase input end of the one RC filter circuit is connected on input side filter respectively and inductance, the output of a RC filter circuit connects the tie point of the first dc-link capacitance and the second dc-link capacitance.The object of this connected mode is the high frequency common mode voltage exchanging input side for eliminating PWM variable-frequency motor drive system, reduces the Conducted Electromagnetic Interference of whole system further, and electrical network is polluted in the interference that anti-locking system produces.
The structure of described three inductance is identical, and the inductance value of three inductance is identical.
A described RC filter circuit comprises three articles of filter branch in parallel, every article of filter branch of the one RC filter circuit comprises resistance and the electric capacity of series connection, resistance in one RC filter circuit is identical, electric resistance structure is identical, capacitance value in one RC filter circuit is identical, and three capacitance structures are identical.
Described outlet side filter circuit comprises three-phase common mode inductance and the 2nd RC filter circuit, the Same Name of Ends of three-phase common mode inductance is the input of outlet side filtering, the different name end of three-phase common mode inductance connects motor by long cable, 2nd RC filter circuit three-phase input end connects the Same Name of Ends of three-phase common mode inductance respectively, and the output of the 2nd RC filter circuit connects the tie point of the first dc-link capacitance and the second dc-link capacitance.The object of this connected mode has two: one to be high frequency common mode voltage for suppressing between inverter 3 outlet side and motor 5, and then suppresses the negative effect such as motor bearing current, leakage current that caused by common-mode voltage.Two is that the inverter that slows down exports rise time of pulse, and voltage reflection phenomenon disappears, and eliminates the overvoltage that PWM inverter is drawn by long cable.
Described 2nd RC filter circuit comprises three articles of filter branch in parallel, and every article of filter branch of the 2nd RC filter circuit comprises the resistance and electric capacity that are connected in series, and three resistances of described 2nd RC filter circuit are identical, and electric resistance structure is identical; Three capacitance values of the 2nd RC filter circuit are identical, and three capacitance structures are identical.
The utility model compared with prior art has following effect: the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O described in the utility model adopts two electromagnetic interface filter topological structures, make full use of passive filter structure simple, realize advantage easily, the basis of traditional passive filter is improved, considers the mechanism of production of Conducted Electromagnetic Interference in system and design.The effect of outlet side filter has two aspects, on the one hand for suppressing the common-mode voltage between PWM variable-frequency motor drive system inverter outlet side and motor, and then suppresses motor shaft voltage, shaft current.On the other hand, the output of outlet side filter reduces the voltage change ratio du/dt of pwm pulse, this design inverter that can slow down exports rise time of pulse, and can eliminate the superpotential adverse effect that PWM inverter drawn by long cable, and voltage reflection phenomenon is disappeared.The effect of input side filter has two: one to be common-mode voltage for suppressing PWM variable-frequency motor drive system rectifying device to exchange input side, reduces common-mode voltage and the Conducted Electromagnetic Interference of whole system further; Two is electromagnetic interference that the input of filter decreases main power source side, prevents the interference produced by system from polluting electrical network.The I/O side filter be made up of two the passive filter structures topology that the utility model proposes, be placed on input side and the outlet side of PWM converter plant respectively, acting in conjunction, suppress du/dt, common-mode voltage, overvoltage and the electromagnetic interference etc. in PWM variable-frequency motor drive system, make system reach Conducted Electromagnetic Interference and do not exceed standard.
Accompanying drawing explanation
Fig. 1 is the theory diagram of the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O described in the utility model;
Fig. 2 is the physical circuit schematic diagram of input side filter;
Fig. 3 is the physical circuit schematic diagram of outlet side filter;
Fig. 4 adopts electric current in PWM variable-frequency motor drive system electromagnetic interference I/O passive filtration unit described in the utility model to flow through route map;
Fig. 5 adopts PWM variable-frequency motor drive system shaft voltage U described in the utility model
sh, shaft current I
bwith common mode current I
cMcurve chart;
Fig. 6 is the Conducted Electromagnetic Interference launching curve figure adopting the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O described in the utility model.
Embodiment
Accompanying drawings embodiment of the present utility model, the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O of present embodiment, as shown in Figure 1, comprise three-phase alternating-current supply 1, input side filter 7, rectifying device 2, inverter 3, outlet side filter 6, long cable 4 and motor 5, the alternating current output of three-phase alternating-current supply 1 connects the input of input side filter 7, the output of input side filter 7 connects the ac input end of rectifying device 2, the DC output end of rectifying device 2 is connected with the direct-flow input end of inverter 3, the ac converter output of inverter 3 connects the input of outlet side filter 6, the output of outlet side filter 6 by long cable 4 for motor 5 provides working power, first dc-link capacitance C
1with the second dc-link capacitance C
2be connected in parallel on the DC bus of rectifying device 2 output after series connection again, the first dc-link capacitance C
1with the second dc-link capacitance C
2tie point be this DC bus mid point,
The output of input side filter 7 is connected with a terminal of outlet side filter 6 output, is connected after input side filter 7 is connected with the output of outlet side filter 6 with DC bus neutral point.
In present embodiment, in PWM variable-frequency motor drive system, rectifying device 2 and inverter 3 are when controlling electric energy and converting, the switching device turned on and off at a high speed can cause the higher du/dt of generation, di/dt, then high frequency common mode voltage and high frequency differential mode voltage is produced, form electromagnetic interference, the common-mode voltage of high frequency is also motor shaft voltage, the main cause that shaft current and leakage current produce, in addition, in the electric system be connected there being long cable, voltage reflection phenomenon can be there is in pulse signal in long cable transmitting procedure, cause the generation of system overvoltage.
In present embodiment, outlet side filter 6 input is connected to the output of inverter 3, and an output part is connected with motor 5, and output is drawn a connecting terminals in addition and is connected to DC bus mid point; The object of this connected mode has two: one to be high frequency common mode voltage for suppressing between inverter 3 outlet side and motor 5, and then suppresses the negative effect such as motor bearing current, leakage current that caused by common-mode voltage.Two is that the inverter that slows down exports rise time of pulse, and voltage reflection phenomenon disappears, and eliminates the overvoltage that PWM inverter is drawn by long cable.
The input of input side filter 7 is connected with three-phase alternating-current supply 1, and an output part is connected to the input of rectifying device 2, draws the output that a connecting terminals is connected on outlet side filter 6 in addition, and is connected with DC bus mid point simultaneously; The object of this connected mode is the high frequency common mode voltage exchanging input side for eliminating PWM variable-frequency motor drive system, reduces the Conducted Electromagnetic Interference of whole system further, and electrical network is polluted in the interference that anti-locking system produces.
As shown in Figure 2, input side filter 7 comprises inductance L
1, inductance L
1', inductance L
1" and a RC filter circuit, a RC filter circuit comprises three articles of filter branch in parallel, and three articles of filter branch of a RC filter circuit comprise the resistance R of series connection respectively
1with electric capacity C
1, series connection resistance R
1' with electric capacity C
1', series connection resistance R
1" with electric capacity C
1";
Inductance L
1, inductance L
1', inductance L
1" one end of these three inductance forms three-phase input end A, B, C of input side filter 7, and shown input side filter 7 three-phase input end A, B and C are connected the ac input end of rectifying device 2 respectively, inductance L
1, inductance L
1', inductance L
1" other end A ', the B ' of these three inductance, the alternating current output of C ' connection three-phase alternating-current supply 1;
Resistance R
1, resistance R
1', resistance R
1" one end be connected to input A ', B ', the C ' of input side filter 7, resistance R
1, resistance R
1', resistance R
1" the other end respectively with electric capacity C
1, electric capacity C
1', electric capacity C
1" link together after series connection; Electric capacity C
1, electric capacity C
1', electric capacity C
1" other end Y shape connect after be connected to the output M of input side filter 7;
Inductance L
1, inductance L
1', inductance L
1" inductance value is equal, and structure is identical;
Resistance R
2, resistance R
2', resistance R
2" resistance is equal, and structure is identical;
Electric capacity C
2, electric capacity C
2', electric capacity C
2" capacitance is equal, and structure is identical;
As shown in Figure 3, outlet side filter 6 comprises three-phase common mode inductance L
cMwith the 2nd RC filter circuit, the 2nd RC filter circuit comprises three articles of filter branch in parallel, and three articles of filter branch of the 2nd RC filter circuit comprise the resistance R of series connection respectively
2with electric capacity C
2, series connection resistance R
2' with electric capacity C
2', series connection resistance R
2" with electric capacity C
2".
Three-phase common mode inductance L
cMthree Same Name of Ends connect the inversion ac output end that U, V, W connect inverters 3; Three-phase common mode inductance L
cMdifferent name end U ', V ', the W ' of three be connected with motor 5 by long cable 4, resistance R
2, resistance R
2', resistance R
2" one end originally Lian Jie three-phase common mode inductance L
cMthree different name end U ', V ', W ', resistance R
2, resistance R
2', resistance R
2" the other end respectively with electric capacity C
2, electric capacity C
2', electric capacity C
2" be in series connection; Electric capacity C
2, electric capacity C
2', electric capacity C
2" after being in parallel, be connected to a lead-out terminal M ';
Output M mono-aspect of shown input side filter 7 is connected with DC bus mid point 0, is connected on the one hand with the lead-out terminal M ' of outlet side filter 6;
Electric capacity C
2, electric capacity C
2', electric capacity C
2" be Y access node structure;
Resistance R
2, resistance R
2', resistance R
2" resistance is equal, and structure is identical;
Electric capacity C
2, electric capacity C
2', electric capacity C
2" capacitance is equal, and structure is identical;
The principle of determining parameters of the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O of present embodiment.
In the process of the passive suppression filter of design I/O, as long as reasonably have selected the parameter of a passive device, just can reach the object reducing system common-mode voltage, and then reduce the Conducted Electromagnetic Interference of system.
Although also there is no clear and definite definition to the common-mode voltage of PWM variable-frequency motor drive system in the world at present, but can according to the mean value of the phase voltage between the definition of single phase system and direct current system (each conductor and regulation reference point (normally or casing)), pwm power converter output terminal mid point is defined as system common-mode voltage to the current potential with reference to ground.So, the common-mode voltage that power inverter exports can connect winding neutral point to the current potential acquisition with reference to ground by measuring induction machine star, and be the system that triangle connects for motor winding, then by artificially arranging a false mid point, and measurement acquisition can be carried out.From then on definition can be found out, the Size-dependent of PWM variable-frequency motor drive system motor side common-mode voltage in choosing with reference to ground, and time different with reference to ground the waveform of common-mode voltage and shape also different.For this reason, in the present embodiment, arranging common-mode voltage is for the current potential with reference to ground with DC bus mid point.
According to above definition, the common-mode voltage that system produces when not taking present embodiment to provide PWM variable-frequency motor drive system electromagnetic interference I/O passive restraining device can represent with following formula,
Wherein, V
u0, V
v0, V
w0be respectively motor 5 input U, V, W to the voltage of DC bus mid point 0, V
0Gfor DC bus mid point voltage to earth.
Present embodiment provides to obtain common mode inductance L in outlet side filter 6
cMmain purpose and suppress the generation of common-mode voltage, its parameter value is arranged to be determined by the size of common-mode voltage.In addition when taking present embodiment to provide the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O, by calculating the common-mode voltage that can obtain now system and produce, represent with following formula,
As can be seen from formula (2), want to reduce system common-mode voltage, then can by the resistance R of suitably design
1, electric capacity C
1, resistance R
2, electric capacity C
2parameter value reach.
After the passive restraining device of access the utility model PWM variable-frequency motor drive system electromagnetic interference I/O, measure the PWM variable-frequency motor drive system shaft voltage U obtained
sh, shaft current I
bwith common mode current I
cMcurve chart as shown in Figure 5, show that the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O that the utility model proposes can suppress the harmful effect of PWM variable-frequency motor drive system effectively, system shaft voltage, shaft current and leakage current have obvious elimination; After employing the utility model device, the electromagnetic interference of main circuit side is measured with LISN, adopt the Conducted Electromagnetic Interference launching curve figure after the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O described in the utility model as shown in Figure 6, now within the scope of the overall mid power drive system Emission Limits all specified at standard GB/T12668.2-2002 of the Conducted Electromagnetic Interference amplitude that produces of system, inhibition is obvious, shows the validity of the passive suppression filter of the I/O that the utility model proposes.
The electromagnetic compatibility problem of research PWM variable-frequency motor drive system, and take effective braking measure for the negative effect that this system produces, from the angle of excision interferencing propagation approach, filter is very effective suppression means, the filter of correct design can make system electromagnetic interference emission intensity be reduced to below electromagnetic compatibility standard limit value, makes equipment and system reach the requirement of international electromagnetic compatibility standard.
Claims (6)
- The passive restraining device of 1.PWM variable-frequency motor drive system electromagnetic interference I/O, comprise the three-phase alternating-current supply connected successively, input side filter, rectifying device, first dc-link capacitance, second dc-link capacitance, inverter, outlet side filter long cable and motor, be attempted by the DC bus of rectifying device outlet side after first dc-link capacitance and the series connection of the second dc-link capacitance, it is characterized in that: the tie point connecting the first dc-link capacitance and the second dc-link capacitance after the output of the output connection outlet side filter of described input side filter.
- 2. the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O according to claim 1, it is characterized in that: described input side filter comprises three-phase input end, three inductance and a RC filter circuit, the three-phase input end of input side filter connects the ac input end of rectifying device respectively by inductance, between the three-phase input end that the three-phase input end of the one RC filter circuit is connected on input side filter respectively and inductance, the output of a RC filter circuit connects the tie point of the first dc-link capacitance and the second dc-link capacitance.
- 3. the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O according to claim 2, is characterized in that: the structure of described three inductance is identical, and the inductance value of three inductance is identical.
- 4. the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O according to claim 2, it is characterized in that: a described RC filter circuit comprises three articles of filter branch in parallel, every article of filter branch of the one RC filter circuit comprises resistance and the electric capacity of series connection, resistance in one RC filter circuit is identical, electric resistance structure is identical, capacitance value in one RC filter circuit is identical, and three capacitance structures are identical.
- 5. the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O according to claim 1, it is characterized in that: described outlet side filter circuit comprises three-phase common mode inductance and the 2nd RC filter circuit, the Same Name of Ends of three-phase common mode inductance is the input of outlet side filtering, the different name end of three-phase common mode inductance connects motor by long cable, 2nd RC filter circuit three-phase input end connects the Same Name of Ends of three-phase common mode inductance respectively, and the output of the 2nd RC filter circuit connects the tie point of the first dc-link capacitance and the second dc-link capacitance.
- 6. the passive restraining device of PWM variable-frequency motor drive system electromagnetic interference I/O according to claim 5, it is characterized in that: described 2nd RC filter circuit comprises three articles of filter branch in parallel, every article of filter branch of the 2nd RC filter circuit comprises the resistance and electric capacity that are connected in series, three resistances of described 2nd RC filter circuit are identical, and electric resistance structure is identical; Three capacitance values of the 2nd RC filter circuit are identical, and three capacitance structures are identical.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201521097898.5U CN205212696U (en) | 2015-12-25 | 2015-12-25 | Passive suppression device of PWM inverter motor actuating system electromagnetic interference I/O |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201521097898.5U CN205212696U (en) | 2015-12-25 | 2015-12-25 | Passive suppression device of PWM inverter motor actuating system electromagnetic interference I/O |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106788118A (en) * | 2017-02-28 | 2017-05-31 | 广东工业大学 | A kind of suppression circuit of Inverter Drive System motor side common-mode voltage |
| CN108155783A (en) * | 2016-12-02 | 2018-06-12 | 长沙市日业电气有限公司 | A kind of circuit for improving overcurrent protection antijamming capability |
| CN113726137A (en) * | 2020-05-26 | 2021-11-30 | 台达电子企业管理（上海）有限公司 | Conversion device |
| CN114400952A (en) * | 2021-12-31 | 2022-04-26 | 青岛海尔空调电子有限公司 | Drive circuit and drive equipment for direct-current variable-frequency motor |
-
2015
- 2015-12-25 CN CN201521097898.5U patent/CN205212696U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108155783A (en) * | 2016-12-02 | 2018-06-12 | 长沙市日业电气有限公司 | A kind of circuit for improving overcurrent protection antijamming capability |
| CN108155783B (en) * | 2016-12-02 | 2020-09-22 | 长沙市日业电气有限公司 | Circuit for improving overcurrent protection anti-interference capability |
| CN106788118A (en) * | 2017-02-28 | 2017-05-31 | 广东工业大学 | A kind of suppression circuit of Inverter Drive System motor side common-mode voltage |
| CN106788118B (en) * | 2017-02-28 | 2019-05-14 | 广东工业大学 | A kind of suppression circuit of Inverter Drive System motor side common-mode voltage |
| CN113726137A (en) * | 2020-05-26 | 2021-11-30 | 台达电子企业管理（上海）有限公司 | Conversion device |
| CN113726137B (en) * | 2020-05-26 | 2023-11-03 | 台达电子企业管理（上海）有限公司 | conversion device |
| CN114400952A (en) * | 2021-12-31 | 2022-04-26 | 青岛海尔空调电子有限公司 | Drive circuit and drive equipment for direct-current variable-frequency motor |
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Granted publication date: 20160504 Termination date: 20161225 |