CN110311549B - Common-mode EMI passive suppression method and device based on split-phase floating - Google Patents

Common-mode EMI passive suppression method and device based on split-phase floating Download PDF

Info

Publication number
CN110311549B
CN110311549B CN201910637675.XA CN201910637675A CN110311549B CN 110311549 B CN110311549 B CN 110311549B CN 201910637675 A CN201910637675 A CN 201910637675A CN 110311549 B CN110311549 B CN 110311549B
Authority
CN
China
Prior art keywords
phase
frequency band
capacitance
common
bridge arm
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910637675.XA
Other languages
Chinese (zh)
Other versions
CN110311549A (en
Inventor
裴雪军
向洋霄
王美娟
杨春宇
孙涛
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huazhong University of Science and Technology
State Grid Hubei Electric Power Co Ltd
Original Assignee
Huazhong University of Science and Technology
State Grid Hubei Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huazhong University of Science and Technology, State Grid Hubei Electric Power Co Ltd filed Critical Huazhong University of Science and Technology
Priority to CN201910637675.XA priority Critical patent/CN110311549B/en
Publication of CN110311549A publication Critical patent/CN110311549A/en
Application granted granted Critical
Publication of CN110311549B publication Critical patent/CN110311549B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • H02M1/44—Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
    • 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
    • H02M1/0003—Details of control, feedback or regulation circuits
    • H02M1/0038—Circuits or arrangements for suppressing, e.g. by masking incorrect turn-on or turn-off signals, e.g. due to current spikes in current mode control

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Power Conversion In General (AREA)
  • Filters And Equalizers (AREA)
  • Inverter Devices (AREA)

Abstract

The invention discloses a common-mode EMI passive suppression method and a device based on split-phase floating ground, wherein the suppression strategy mainly comprises three key design links of a split-phase floating ground radiator, an absorption capacitor, a low EPC (parasitic capacitor) AC filter inductor and the like, and realizes high-efficiency suppression of a common-mode interference source and a common-mode conduction path.

Description

Common-mode EMI passive suppression method and device based on split-phase floating
Technical Field
The invention relates to the technical field of conducted EMI suppression of power electronic devices, in particular to a common-mode EMI passive suppression method and device based on split-phase floating.
Background
Due to its high-efficiency and controllable electric energy conversion characteristics, power electronic devices have been widely used in many modern industries that require high reliability, such as ships, airplanes, high-speed railways, power grids, and the like. However, the high frequency and high speed switching of the switching devices in the power electronic devices causes voltage and current pulses with a rate of change of giga V/S, A/S, and further generates wide frequency harmonics of switching order and above, which cause serious electromagnetic interference problems to the system. In recent years, power electronic devices are facing more and more electromagnetic interference challenges as power electronic devices have been developed to achieve higher power density.
The high frequency band of conducted electromagnetic interference is mainly determined by common mode electromagnetic interference, and common mode EMI filters are usually adopted in engineering to realize the suppression of common mode electromagnetic interference. However, for common mode electromagnetic interference in the frequency band above mhz, the distributed coupling parameters inside the common mode filter need to be strictly controlled, so as to reduce the influence of the stray parameters on the high frequency performance of the filter. However, the design and manufacturing cost of the common mode filter is greatly increased, and meanwhile, there is a high technical barrier to improve the high-frequency performance of the common mode filter. Therefore, the filtering strategy can be assisted by designing the power electronics device, thereby reducing the excessive dependence on the high-frequency performance of the common-mode EMI filter.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to solve the technical problems that the common mode interference source ringing effect in a three-phase two-level power electronic device is difficult to eliminate, and meanwhile, the high-frequency-band common mode electromagnetic interference is difficult to inhibit.
In order to achieve the above object, in one aspect, the present invention provides a passive common-mode EMI suppression method based on split-phase floating, including:
each phase of bridge arm in the power electronic device corresponds to a radiator, and each phase of radiator is used for radiating the IGBT module on the phase of bridge arm; setting a preset distance between two adjacent radiators, and arranging radiating teeth of the two adjacent radiators in a staggered manner;
the magnetic core of the alternating current output filter inductor of the power electronic device adopts a double-overlapping structure so as to relatively reduce the number of turns of the winding under the same inductance value and relatively reduce the distributed capacitance between turns and the turns to the magnetic core;
and an absorption capacitor is connected between the positive bus and the negative bus of each phase of bridge arm in a bridging manner, and the ringing frequency of the common-mode interference source is controlled by presetting the capacitance value and the equivalent inductance parameter of the absorption capacitor.
Optionally, the ringing frequency of the interference source is controlled by:
determining the impedance characteristic of each phase of bridge arm according to the circuit parameter of each phase of bridge arm, wherein the equivalent circuit of each phase of bridge arm presents the capacity in the first frequency band and the third frequency band; in the second frequency band and the fourth frequency band, the circuit of each phase is inductive, and ringing is not generated at this time; in a full frequency band, the first frequency band, the second frequency band, the third frequency band and the fourth frequency band are sequentially and continuously distributed in a connected mode;
by designing the capacitance value of the absorption capacitor and the parasitic inductance value thereof, the frequency interval in which the third frequency band is located can be controlled to be more than 30MHZ, so that no high-frequency ringing exists in the frequency band below 30MHZ, and the ringing effect of the frequency band above 30MHZ can be inhibited under skin-friendly damping.
Optionally, each phase bridge arm corresponds to one radiator, and then the parasitic capacitance C of the ac filter inductor of each phase at this timefAnd the sum C of the earth capacitances of the IGBT on the positive busbar and the negative busbargdAnd point-to-ground capacitor C in IGBT outputgaCompared with C of each phase of all phase bridge arms sharing one radiatorf、CgdAnd CgaThe flow loop of common mode interference is blocked by relative reduction.
Optionally, the equivalent parallel capacitance of the ac output filter inductor should be in the same order as the ground capacitance of each phase of the heat sink.
In another aspect, the present invention provides a power electronic device comprising: a plurality of heat sinks;
each phase of bridge arm in the power electronic device corresponds to one radiator, and each phase of radiator is used for radiating the IGBT module on the phase of bridge arm; setting a preset distance between two adjacent radiators, and arranging radiating teeth of the two adjacent radiators in a staggered manner;
the magnetic core of the alternating current output filter inductor of the power electronic device adopts a double-overlapping structure so as to relatively reduce the number of turns of a winding under the same inductance value and relatively reduce the distributed capacitance between turns and the magnetic core of the turns;
an absorption capacitor is connected between the positive bus and the negative bus of each phase of bridge arm of the power electronic device in a bridging manner, and the capacitance value and the equivalent inductance parameter of the absorption capacitor can control the ringing frequency of the common-mode interference source.
Optionally, the circuit parameters of each phase of bridge arm determine the impedance characteristics of each phase of bridge arm, wherein the equivalent circuit of each phase of bridge arm presents the capacitance in the first frequency band and the third frequency band; in the second frequency band and the fourth frequency band, the circuit of each phase is inductive, and ringing is not generated at this time; in a full frequency band, the first frequency band, the second frequency band, the third frequency band and the fourth frequency band are sequentially and continuously distributed in a connected mode;
by designing the capacitance value of the absorption capacitor and the parasitic inductance value thereof, the frequency interval in which the third frequency band is located can be controlled to be more than 30MHZ, so that no high-frequency ringing exists in the frequency band below 30MHZ, and the ringing effect of the frequency band above 30MHZ can be inhibited under skin-friendly damping.
Optionally, each phase bridge arm corresponds to one radiator, and then the parasitic capacitance C of the ac filter inductor of each phase at this timefAnd the sum C of the earth capacitances of the IGBT on the positive busbar and the negative busbargdAnd point-to-ground capacitor C in IGBT outputgaCompared with C of each phase of all phase bridge arms sharing one radiatorf、CgdAnd CgaThe flow loop of common mode interference is blocked by relative reduction.
Optionally, the equivalent parallel capacitance of the ac output filter inductor should be in the same order as the ground capacitance of each phase of the heat sink.
Generally, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:
the invention provides a common-mode EMI passive suppression method and a common-mode EMI passive suppression device based on phase splitting floating, the common-mode EMI passive suppression method based on phase splitting floating design can realize efficient suppression of common-mode EMI under the condition of no EMI filter, has high-performance high-frequency common-mode EMI suppression performance, and can enable the EMI filter to concentrate on low-frequency EMI as an auxiliary suppression means, thereby greatly reducing the design cost of the EMI filter. The invention provides a common-mode EMI passive suppression method and device based on split-phase floating, which are simple in design flow and low in technical barrier; the design and device cost is low; the high-frequency ringing in a common-mode interference source can be greatly suppressed; the high-frequency common-mode conduction EMI circulation path can be effectively blocked.
Drawings
FIG. 1 is a schematic diagram of a phase-split floating-based passive common-mode EMI suppression method provided by the present invention;
FIG. 2 is a schematic diagram of a topology model of a three-phase two-level power electronic device according to the present invention;
FIG. 3 is a schematic diagram of a high frequency model of a three-phase two-level power electronic device according to the present invention;
FIG. 4 is a schematic diagram of the common mode EMI prediction result of the three-phase two-level power electronic device according to the present invention;
FIG. 5 is a schematic diagram of a low EPC AC filter inductor design with a stacked structure according to the present invention;
FIG. 6 is a schematic diagram of a high-frequency model of a three-phase two-level power electronic device based on split-phase floating ground provided by the invention;
FIG. 7 is a schematic diagram of a passive ringing equivalent circuit of a three-phase two-level power electronic device based on split-phase floating ground provided by the invention;
FIG. 8 is a schematic diagram of a high-frequency mathematical model of each bridge arm of a three-phase two-level power electronic device based on split-phase floating ground provided by the invention;
FIG. 9 is a schematic diagram of common mode EMI conduction paths of a split-phase floating-ground based three-phase two-level power electronic device provided by the present invention;
FIG. 10 is a schematic diagram of a mathematical model of the common-mode EMI conduction path impedance of a three-phase two-level power electronic device based on a split-phase floating ground according to the present invention;
FIG. 11 is a schematic diagram illustrating the amplitude-frequency characteristics of the common mode current provided by the present invention in the full frequency band;
FIG. 12 is a graph illustrating the frequency domain comparison of the common mode interference source provided by the present invention;
FIG. 13 is a diagram illustrating the time domain comparison result of the ringing effect of the common mode interference source provided by the present invention;
fig. 14 is a frequency domain comparison of common mode interference provided by the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
In order to achieve the above purpose, the present invention mainly comprises the following key technical solutions:
(1) the IGBT modules on the bridge arms of each phase in the three-phase two-level power electronic device radiate heat through independent radiators, and the radiators between the phases are separated by a certain distance so as to reduce the capacitive coupling between the radiators of each phase as much as possible. In a similar way, the radiators of all phases and the device shell are designed to have a certain distance, so that the decoupling between the radiators and the ground loop is realized. The step is the basis for realizing interference source ringing suppression and plays a role in blocking a common-mode EMI conduction path.
Preferably, the bridge arm can be fixed between the heat sink and the casing by using a support made of an insulating material such as plastic.
Preferably, the heat radiators of the phases are staggered and opposite by the side edges of the heat radiating teeth, so that the corresponding areas of the heat radiators between the phases can be further reduced, and the capacitive coupling is reduced.
(2) The alternating current output filter inductor of the three-phase two-level power electronic device is designed by adopting a low Equivalent Parallel Capacitor (EPC), so that decoupling between an alternating current side and a bridge arm is realized in a high-frequency band, the influence of a parasitic parameter of the alternating current side on a ringing effect of an Interference source is shielded, and a function of blocking a common mode ElectroMagnetic Interference (EMI) circulation path is also achieved.
Preferably, the inductance EPC can be effectively reduced by appropriately increasing the distance from turn to turn of the coil. In addition, the double-layer magnetic core with high magnetic permeability is adopted, so that the number of the windings required by the inductor is less under the same inductance value, and the EPC can be effectively reduced.
(3) An absorption capacitor is bridged between a positive bus and a negative bus of each phase of bridge arm, and based on the parameters of lead wire Inductance, junction capacitance, capacitance to ground and the like of an IGBT module power terminal, reasonable capacitance values of the absorption capacitor and Equivalent Inductance (ES L) parameters are calculated, so that the ringing frequency of an interference source is controlled to be at a very high frequency (the skin effect of the equipment can be effectively inhibited) or a very low frequency (the common filter design can be effectively inhibited).
FIG. 1 is a schematic diagram of a phase-split floating-based passive common-mode EMI suppression method provided by the present invention; as shown in fig. 1, the passive EMI suppression method provided by the present invention includes the following steps:
design of a dispersed floating radiator: each phase of bridge arm in the power electronic device corresponds to a radiator, and each phase of radiator is used for radiating the IGBT module on the phase of bridge arm; the adjacent two-phase radiators are arranged at a preset distance, and the radiating teeth of the adjacent two-phase radiators are arranged in a staggered mode.
Design of low EPC alternating current filter inductance: the magnetic core of the alternating current output filter inductor provided with the power electronic device adopts a double-overlapping structure so as to relatively reduce the number of turns of the winding under the same inductance value and relatively reduce the distributed capacitance between turns and the magnetic core of the turns.
And (3) calculating an absorption capacitance parameter: and an absorption capacitor is connected between the positive bus and the negative bus of each phase of bridge arm in a bridging manner, and the ringing frequency of the common-mode interference source is controlled by presetting the capacitance value and the equivalent inductance parameter of the absorption capacitor.
The work mode interference conduction path can be blocked by the design of the dispersive floating radiator and the design of the low EPC alternating current filter inductor, and common mode interference ringing can be inhibited by the design of the dispersive floating radiator, the design of the low EPC alternating current filter inductor and the calculation of absorption capacitance parameters.
The invention provides a three-phase two-level power electronic device, the topological structure of which is shown in figure 2, and the technical scheme of the invention is explained, which specifically comprises the following parts:
(1) accurate establishment of three-phase two-level power electronic device high-frequency model
Before designing a split-phase floating ground filtering scheme, parasitic parameters of key components such as an IGBT module, a busbar, an AC/DC cable, a DC support capacitor and a load in the power electronic device need to be extracted accurately. The lead inductance and the ground capacitance of each terminal of the IGBT module of the active device are obtained through finite element calculation; the capacitance value of the collector-emitter junction under the rated voltage in the IGBT module is obtained by fitting a capacitance value curve given by a data manual; stray parameters of the direct-current busbar are extracted through finite element analysis; stray parameters of other passive components are measured with an impedance analyzer. The stray parameter extraction results of each key component of the three-phase two-level power electronic device used in the invention are shown in table 1, and the device high-frequency model is shown in fig. 3.
Based on the method, a time domain prediction simulation model is established in the Ansys Simplorer, time domain prediction results of the common-mode interference source and the common-mode conducted interference are obtained respectively, the time domain prediction results are converted into a frequency domain through FFT analysis and compared with actually-measured interference, and the comparison result is shown in figure 4, so that the accuracy of the established system high-frequency model is verified.
TABLE 1
Figure BDA0002130823950000071
Wherein, LACinductorRepresenting the inductance value, C, of the AC filter inductorACinductorRepresenting the parasitic capacitance, R, of the AC filter inductanceACinductorRepresenting the resistance of the AC filter inductance, Ldc-linkRepresenting the parasitic inductance value, C, of the DC support capacitordc-linkRepresenting the capacitance, R, of the DC support capacitordc-linkResistance representing the tributary support capacitance, LACcapacitorRepresenting parasitic inductance value, C, of the AC filter capacitorACcapacitorRepresenting the capacitance, R, of the AC filter capacitorACcapacitorRepresenting the resistance of the AC filter capacitor, LloadRepresenting the inductance value of the load, CloadRepresenting the parasitic capacitance to ground, R, of the loadloadRepresenting the value of the load resistance, LAC-cableRepresenting the equivalent inductance value of the AC cable, LDC-cableRepresents the equivalent inductance value, R, of the DC cableDC-cableRepresents the equivalent resistance value, R, of the DC cableAC-cableDenotes the equivalent resistance value of the AC cable, LARepresenting parasitic inductance of the A-phase busbar, LBRepresenting parasitic inductance of the B-phase busbar, LCRepresenting parasitic inductance, R, of the C-phase busbarARepresents the A-phase bus bar resistance, RBRepresents B-phase bus bar resistance, RCRepresents C-phase bus bar resistance, CCRepresenting the capacitance to ground, C, of the upper arm collector of the IGBT moduleORepresents the point output point of the IGBT module to the ground capacitance, CEIndicating the emitter-to-ground capacitance of the lower arm of the IGBT Module, LiCRepresenting parasitic inductance of the collector segment of the upper arm of the IGBT Module, LiORepresenting parasitic inductance of the IGBT module midpoint output terminal, LiERepresenting parasitic inductance, C, of lower arm emitter terminal of IGBT modulejRepresenting the collector-emitter parasitic capacitance, C, of the IGBT chipgcRepresenting the gate-collector parasitic capacitance, C, of the IGBT chipgeRepresenting the gate-emitter parasitic capacitance of the IGBT chip.
(2) Split-phase floating ground radiator design
The structure of the phase-separated floating heat sink is shown in FIG. 4. The IGBT modules on the bridge arms of each phase radiate heat through independent radiators, the radiators between the phases are separated by a certain distance, and radiating teeth are arranged in a staggered mode to reduce capacitive coupling between the radiators of each phase as far as possible. Meanwhile, the radiators of all phases are isolated from the device shell through the insulating support columns, so that the decoupling between the radiators and a ground loop is realized. With this design, the coupling between the phase radiators can easily reach a small value, and the coupling capacitance between the phase radiators and the ground can be roughly calculated as:
C＝S/d
where is the dielectric constant, S is the corresponding area between the heat sink and the chassis, and d is the distance between the heat sink and the chassis. The coupling capacitance between the heat sink and the ground in the present invention should be at least an order of magnitude smaller than the capacitance to ground of the IGBT module, based on which the capacitance to ground of each phase heat sink in the actual experimental bench is designed to be 15 pF.
(3) Low EPC AC filter inductor design
The structure of the low EPC ac filter inductor is shown in fig. 5. The magnetic core adopts a double-overlapping structure, and the number of turns of the winding is greatly reduced under the same inductance value, so that the distributed capacitance of turns and turns to the magnetic core is effectively reduced. The EPC of the AC output filter inductor designed by the invention is in the same order of magnitude as the ground capacitance of each phase of radiator to realize better AC side decoupling effect, so that the EPC of each phase of AC filter inductor in an actual experiment bench is also designed to be 15 pF.
(4) Absorption capacitance design
The control of the ringing frequency can be achieved by selecting the capacitance of the absorption capacitor and ES L based on the design of (2) and (3). at this time, in the high frequency band (the frequency point where the ac output inductance changes from inductive to capacitive, typically in the order of hundred kilohertz), the high frequency model of the system and the passive ringing equivalent circuit of the device are shown in fig. 6 and 7. at this time, the impedance of each phase (the circuit in the grey bottom frame) can be expressed as:
Figure BDA0002130823950000091
wherein the content of the first and second substances,
Figure BDA0002130823950000092
x is A, B or C, the upper bridge arm is conducted, CupX＝Cc+Co，CdnX＝CE(ii) a Lower arm on, CupX＝CC，CdnX＝CO+CE。
In the above formula, ω is the frequency, LigbtIs IGBT module lead inductance, CaddTo absorb capacitance value of capacitor, LaddTo absorb stray inductances of the capacitors, CC、CO、CEThe ground capacitances C of the collector of the upper bridge arm, the emitter of the upper bridge arm and the emitter of the lower bridge arm of the IGBT module respectivelyjIs an IGBT junction capacitance. CX、CupXAnd CdnXIs an intermediate variable.
The impedance characteristic curve of Z in the full frequency band is shown in fig. 8, in which,
Figure BDA0002130823950000093
Figure BDA0002130823950000094
in the frequency bands I and III, a circuit in the grey bottom frame presents the capacitance and can resonate with a busbar stray inductance to generate ringing. In addition, theIn the II and IV frequency bands, the circuit in the gray bottom frame is inductive and does not produce ringing, therefore, the voltage f can be reduced by reasonably selecting the capacitance value of the absorption capacitor and the ES L1And will f2And f3The method is pushed to the frequency range above 30MHz which is not concerned by conducted electromagnetic interference, in the frequency range above 30MHz, the system damping is very large, high-frequency ringing can be quickly suppressed, and the high-frequency ringing is difficult to observe on an interference source frequency spectrum, and the selected absorption capacitance value is 4.7uF, and the ES L is 20 nH.
(4) Common mode interference conduction path analysis
In the case of using a phase-splitting floating heat sink, the common-mode conduction path of the three-phase two-level power electronic device is converted into a star-delta path as shown in fig. 9 (a), which can be further simplified into a circuit as shown in fig. 9 (b). Wherein the content of the first and second substances,
Figure BDA0002130823950000095
Figure BDA0002130823950000101
wherein, CgdIs the sum of the earth capacitances of the IGBT on the positive busbar and the negative busbar, CgaIs the capacitance to ground of the output midpoint of the IGBT. CsinkIs a heat sink capacitance to ground.
It is noted that the high-frequency model of the common-mode interference conduction path is the same for the common three-phase two-level device and the three-phase two-level device based on the split-phase floating heat sink (fig. 9 (b)), and the difference is that C in the three-phase two-level device based on the split-phase floating heat sinkf,Cgd,CgaIs greatly reduced. CfIs the parasitic capacitance of the AC filter inductor.
Through the design of (2) and (3), the following parameter relationships are ubiquitous for general systems:
Cf,Cgd,Cga＜＜Cl
Ld,La＜＜Lf
wherein, ClL stray capacitance of load to grounda＝LACcable+Lload，Ld＝LDCcable，Lf＝LACinductor。
At this time, the expression of the common-mode conduction path impedance in the gray bottom frame range is:
Figure BDA0002130823950000102
the impedance characteristics of the circuit at different frequency bands are shown in fig. 10 and table 2, and further, the common mode current I measured at the ISN of the line impedance stabilizing network LCMAnd common mode interference source VCMThe mathematical relationship between the two is as follows:
Figure BDA0002130823950000103
when V isCMThe amplitude-frequency characteristic of the common mode current in the full frequency band is shown in fig. 11 when the signal has an amplitude of 1 and a phase of 0 in the full frequency band. In frequency bands II, IV, VI, the mathematical expression for the common mode current is:
Figure BDA0002130823950000104
wherein line () represents a linear function. With CgdThe denominator of the above formula is increased, the numerator is kept unchanged, and the common-mode current I of the system is kept at the momentCMIs reduced.
In frequency bands II, IV, VI, the mathematical expression for the common mode current is:
Figure BDA0002130823950000111
with Cgd,CgaAnd CfThe denominator of the above formula is increased, the numerator is decreased or kept unchanged, and similarly, the common mode current I of the systemCMIs reduced. Therefore, the suppression scheme provided by the invention can realize the common mode in the full frequency band theoreticallySuppression of interfering conduction paths.
TABLE 2
Figure BDA0002130823950000112
Experimental verification
The common-mode electromagnetic interference test is carried out strictly according to the requirements of the DO-160 standard, and the common-mode interference source when the phase separation floating ground suppression strategy is adopted and the common-mode interference frequency spectrum measured at L ISN are compared in the range of 150kHz-30 MHz.
Fig. 12 shows the frequency domain comparison result of the common mode interference source, and it can be seen that the common mode interference source has no high frequency interference generated by ringing in the frequency spectrum after the phase separation floating. Fig. 13 compares the time-domain waveforms of the ring signals in the interference sources, and it is obvious that the high-frequency ring in the common-mode interference source is quickly suppressed after the split-phase floating suppression strategy is adopted. The invention proves that the suppression of the common-mode interference source can be effectively realized.
Fig. 14 shows the frequency domain comparison result of conducted common mode interference, and it can be seen that the floating phase suppression strategy reduces the magnitude of the common mode interference almost in the full frequency band (especially in the high frequency band). Therefore, experiments prove that the invention can effectively realize the suppression of the common-mode interference of the three-phase two-level device.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (6)

1. A common-mode EMI passive suppression method based on phase-splitting floating is characterized by comprising the following steps:
each phase of bridge arm in the power electronic device corresponds to a radiator, and each phase of radiator is used for radiating the IGBT module on the phase of bridge arm; setting a preset distance between two adjacent radiators, and arranging radiating teeth of the two adjacent radiators in a staggered manner;
the magnetic core of the alternating current output filter inductor of the power electronic device adopts a double-overlapping structure so as to reduce the number of turns of the winding under the same inductance value and reduce the distributed capacitance between turns and between turns to the magnetic core;
an absorption capacitor is bridged between the positive bus and the negative bus of each phase of bridge arm, and the ringing frequency of the common-mode interference source is controlled by presetting the capacitance value and the equivalent inductance parameter of the absorption capacitor;
controlling the ringing frequency of the interference source by:
determining the impedance characteristic of each phase of bridge arm according to the circuit parameter of each phase of bridge arm, wherein the equivalent circuit of each phase of bridge arm presents the capacity in the first frequency band and the third frequency band; in the second frequency band and the fourth frequency band, the circuit of each phase is inductive; in a full frequency band, the first frequency band, the second frequency band, the third frequency band and the fourth frequency band are sequentially and continuously distributed in a connected mode;
by designing the capacitance value of the absorption capacitor and the parasitic inductance value thereof, the frequency interval in which the third frequency band is located can be controlled to be more than 30MHZ, so that no high-frequency ringing exists in the frequency band below 30MHZ, and the ringing effect of the frequency band above 30MHZ can be inhibited under skin-friendly damping.
2. The split-phase floating-ground-based common-mode EMI passive suppression method according to claim 1, wherein each phase bridge arm corresponds to a radiator, and then parasitic capacitance C of AC filter inductance of each phase at the momentfAnd the sum C of the earth capacitances of the IGBT on the positive busbar and the negative busbargdAnd point-to-ground capacitor C in IGBT outputgaCompared with C of each phase of all phase bridge arms sharing one radiatorf、CgdAnd CgaAnd the circulation loop of common mode interference is reduced and blocked.
3. The passive phase-splitting floating-ground-based common-mode EMI suppression method according to claim 1, wherein equivalent parallel capacitance of the AC output filter inductor is in the same order of magnitude as the ground capacitance of each phase radiator.
4. A power electronic device, comprising: a plurality of heat sinks;
each phase of bridge arm in the power electronic device corresponds to one radiator, and each phase of radiator is used for radiating the IGBT module on the phase of bridge arm; setting a preset distance between two adjacent radiators, and arranging radiating teeth of the two adjacent radiators in a staggered manner;
the magnetic core of the alternating current output filter inductor of the power electronic device adopts a double-overlapping structure so as to reduce the number of turns of a winding under the same inductance value and reduce the distributed capacitance between turns and between turns to the magnetic core;
an absorption capacitor is bridged between a positive bus and a negative bus of each phase of bridge arm of the power electronic device, and the ringing frequency of the common-mode interference source is controlled by presetting the capacitance value and the equivalent inductance parameter of the absorption capacitor;
determining the impedance characteristic of each phase of bridge arm by the circuit parameters of each phase of bridge arm, wherein the equivalent circuit of each phase of bridge arm presents the capacity in the first frequency band and the third frequency band; in the second frequency band and the fourth frequency band, the circuit of each phase is inductive; in a full frequency band, the first frequency band, the second frequency band, the third frequency band and the fourth frequency band are sequentially and continuously distributed in a connected mode; by designing the capacitance value of the absorption capacitor and the parasitic inductance value thereof, the frequency interval in which the third frequency band is located can be controlled to be more than 30MHZ, so that no high-frequency ringing exists in the frequency band below 30MHZ, and the ringing effect of the frequency band above 30MHZ can be inhibited under skin-friendly damping.
5. A power electronic device according to claim 4, wherein each phase leg corresponds to a heat sink, and the parasitic capacitance C of the AC filter inductance of each phase is the samefAnd the sum C of the earth capacitances of the IGBT on the positive busbar and the negative busbargdAnd point-to-ground capacitor C in IGBT outputgaCompared with C of each phase of all phase bridge arms sharing one radiatorf、CgdAnd CgaAnd the circulation loop of common mode interference is reduced and blocked.
6. A power electronic device according to claim 4, characterised in that the equivalent parallel capacitance of the AC output filter inductance is of the same order of magnitude as the capacitance to ground of each phase of the heat sink.
CN201910637675.XA 2019-07-15 2019-07-15 Common-mode EMI passive suppression method and device based on split-phase floating Active CN110311549B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910637675.XA CN110311549B (en) 2019-07-15 2019-07-15 Common-mode EMI passive suppression method and device based on split-phase floating

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910637675.XA CN110311549B (en) 2019-07-15 2019-07-15 Common-mode EMI passive suppression method and device based on split-phase floating

Publications (2)

Publication Number Publication Date
CN110311549A CN110311549A (en) 2019-10-08
CN110311549B true CN110311549B (en) 2020-08-04

Family

ID=68081359

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910637675.XA Active CN110311549B (en) 2019-07-15 2019-07-15 Common-mode EMI passive suppression method and device based on split-phase floating

Country Status (1)

Country Link
CN (1) CN110311549B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109347135B (en) * 2018-11-14 2020-06-02 华中科技大学 Common-mode conduction EMI modeling method and device of MMC three-phase grid-connected inverter system
CN111884500B (en) * 2020-08-03 2022-02-22 中车青岛四方车辆研究所有限公司 Method for suppressing common-mode conducted interference of vehicle-mounted charger

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5552976A (en) * 1994-06-10 1996-09-03 Northrop Grumman Corporation EMI filter topology for power inverters
DE10039957A1 (en) * 2000-08-16 2002-03-07 Siemens Ag Device for basic interference suppression of a matrix converter
CN107623435B (en) * 2017-09-05 2019-11-01 华北电力大学 The two-way common mode differential mode EMI filter and its design method of photovoltaic module tandem

Also Published As

Publication number Publication date
CN110311549A (en) 2019-10-08

Similar Documents

Publication Publication Date Title
Fang et al. Study of the characteristics and suppression of EMI of inverter with SiC and Si devices
RU2708638C2 (en) Inverter with high specific power
Liu et al. EMI suppression in voltage source converters by utilizing dc-link decoupling capacitors
Jiang et al. Study of conducted EMI reduction for three-phase active front-end rectifier
US9479105B2 (en) Input EMI filter for motor drive including an active rectifier
CN110311549B (en) Common-mode EMI passive suppression method and device based on split-phase floating
Xing et al. Behavioral modeling methods for motor drive system EMI design optimization
CN204316327U (en) A kind of electromagnetic interface filter for dual feedback wind power generation system
Narayanasamy et al. Impact of cable and motor loads on wide bandgap device switching and reflected wave phenomenon in motor drives
Xue et al. EMI noise mode transformation due to propagation path unbalance in three-phase motor drive system and its implication to EMI filter design
Son et al. Conducted EMI in PWM inverter for household electric appliance
CN109714079B (en) Anti-interference circuit for power line carrier communication
Zhai et al. Comparison of two filter design methods for conducted EMI suppression of PMSM drive system for electric vehicle
Morris et al. Comparison and evaluation of common mode EMI filter topologies for GaN-based motor drive systems
Mousavi et al. Reduction EMI of BLDC motor drive based on software analysis
Wunsch et al. Impact of diode-rectifier on EMC-noise propagation and filter design in AC-fed motor drives
CN204334316U (en) Reduce the device of switching circuit electromagnetic noise
CN107332434B (en) Common-mode current suppression circuit of motor driving system
Yang et al. Analysis and optimization of high-frequency switching oscillation conducted CM current considering parasitic parameters based on a half-bridge power module
Li et al. Optimization design of EMI filter with chaotic PWM in DC-DC converters
CN110380402B (en) Method and system for selecting filter in direct current transmission system
Wang et al. Negative capacitance and its applications on parasitic cancellation for EMI noise suppression
CN105356732A (en) Converter system and method for inhibiting resonance
Liu et al. THD and EMI performance study of foil-wound inductor of LCL filter for high power density converter
Hızarcı et al. Reducing electromagnetic interference in three-level T-type isolated bidirectional DC-DC converter using a snubber circuit

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right
TA01 Transfer of patent application right

Effective date of registration: 20200108

Address after: 430074 Hubei Province, Wuhan city Hongshan District Luoyu Road No. 1037

Applicant after: Huazhong University of Science and Technology

Applicant after: State Grid Hubei Electric Power Co., Ltd.

Address before: 430074 Hubei Province, Wuhan city Hongshan District Luoyu Road No. 1037

Applicant before: Huazhong University of Science and Technology

GR01 Patent grant
GR01 Patent grant