CN108390572A - Active third-harmonic zero-sequence voltage matrix converter input current waveform optimizes topological structure - Google Patents
Active third-harmonic zero-sequence voltage matrix converter input current waveform optimizes topological structure Download PDFInfo
- Publication number
- CN108390572A CN108390572A CN201810093390.XA CN201810093390A CN108390572A CN 108390572 A CN108390572 A CN 108390572A CN 201810093390 A CN201810093390 A CN 201810093390A CN 108390572 A CN108390572 A CN 108390572A
- Authority
- CN
- China
- Prior art keywords
- current
- filter
- sequence voltage
- harmonic
- active
- 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.)
- Granted
Links
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
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M5/4585—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only having a rectifier with controlled elements
-
- 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
- H02M1/14—Arrangements for reducing ripples from dc input or output
Abstract
The present invention discloses a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topological structure, including the load of three-phase alternating-current supply, input filter, voltage selector IVS, busbar filter, third-harmonic zero-sequence voltage circuit, current source inverter CSI, three-phase alternating current, output inductor；The voltage selector includes rectification stage and three two-way switch, rectification stage includes three bridge arms of wholly-controled device composition, the third-harmonic zero-sequence voltage circuit includes the y bridge arms and a harmonic injection current filtering inductance Ly of wholly-controled device composition, and the topological structure is equipped with busbar filter on busbar.The topological structure can effectively inhibit input current sector switch caused by switching of the active third-harmonic zero-sequence voltage matrix converter due to the bus current of high frequency and the harmonic injection inductive current of low frequency to distort, and improve input current waveform.
Description
Technical field
The present invention relates to a kind of electrical energy changer, more particularly to one kind can improve active third-harmonic zero-sequence voltage matrix and become
The topological structure of parallel operation input current waveform.
Background technology
Matrix converter (MC) is a kind of AC-AC power inverters without large capacity energy-storage travelling wave tube, is had small, again
The advantages that measuring light, reliability height, energy capable of bidirectional flowing and sineization input and output, is worldwide widely studied.It is double
Grade formula matrix converter is a kind of subclass of matrix converter, has clamp circuit is simple, change of current control strategy is easy to implement etc.
Advantage, but there are input power factor angle control range is small, the weak limitation of reactive power control capability.In such background
Under, the active third-harmonic zero-sequence voltage matrix converter (H3IMC) of Research of New Matrix Converter based on active third-harmonic zero-sequence voltage technology
Studied personnel's proposition, as shown in Fig. 1.Active third-harmonic zero-sequence voltage matrix converter without large capacity energy-storage travelling wave tube, because
This inherits most of advantage of dual-level matrix frequency converter, but the harmonic injection circuit that H3IMC includes also can be to input electricity
Desired reactive power is injected in source, this makes it breach the weak limitation of traditional MC reactive power control capabilities in theory.
However, there is distortion, simulation waveform such as Fig. 4 at sector switch for attached topological structure input current shown in FIG. 1
It is shown.This is because at sector switch, the two-phase of the change of current occurs, a phase is bus current, is influenced by inverter and is in copped wave
Shape, another phase are harmonic injection circuit filtering inductive current, by inductor filter therefore predominantly low-frequency current.Both switching
When, since instantaneous value is uncertain at change of current point for busbar chopper current, the switching between the inductive current of low frequency will produce electricity
Stream mutation, causes input filter to shake, to make input current abnormality.
Invention content
The purpose of the present invention is that active third-harmonic zero-sequence voltage matrix converter input current wave can be improved by providing one kind
The topological structure of shape can effectively inhibit active third-harmonic zero-sequence voltage matrix converter bus current and low frequency due to high frequency
Input current sector switch caused by the switching of harmonic injection inductive current distorts, and improves input current waveform.
In order to achieve the above objectives, solution of the invention is：
In order to achieve the above functions, the present invention provides a kind of active third-harmonic zero-sequence voltage matrix converters to improve topology knot
Structure, including three-phase alternating-current supply, input filter, voltage selector IVS, busbar filter, third-harmonic zero-sequence voltage circuit, electric current
Type inverter CSI, three-phase alternating current load, output inductor；
Voltage selector includes rectification stage and three two-way switch, and rectification stage includes three bridges of wholly-controled device composition
Arm, third-harmonic zero-sequence voltage circuit include the y bridge arms and a harmonic injection current filtering inductance L of wholly-controled device compositiony；
Three-phase alternating-current supply is connected on the three-phase input end of voltage selector by input filter, voltage selector IVS's
X, the both ends z are connected to DC terminal p, n of current source inverter CSI by busbar filter, and the ends y are connect by third-harmonic zero-sequence voltage circuit
To two-way switch, three-phase alternating current loads the three-phase alternating current output end that current source inverter CSI is connected to by output inductor.
Busbar filter includes two filter inductance Lx、Lz, two damping resistance Rx、RzWith a filter capacitor Cpn.Filtering
Inductance Lx、LzIt is connected on the both ends x, z of voltage selector IVS outputs respectively, and is separately connected the DC side of current source inverter CSI
P, the both ends n, damping resistance Rx、RzIt is connected in parallel on filter inductance Lx、LzBoth ends, filter capacitor CpnIt is connected directly across current source inverter
The both ends DC side p, n of CSI.
Input filter only includes three input filter inductance, does not include input filter capacitor and damping resistance.
Voltage selector IVS includes rectification stage and three two-way switch, and rectification stage includes three of wholly-controled device composition
Bridge arm, each two-way switch are made of two wholly-controled device cascode grades, individual two poles of each wholly-controled device inverse parallel one
Pipe.
Third-harmonic zero-sequence voltage circuit includes the y bridge arms and a harmonic injection current filtering inductance of wholly-controled device composition
Ly, y bridge arms are connected across the both ends DC side p, n of current source inverter CSI, harmonic injection current filtering inductance LyConnect y bridge arms and
Two-way switch.
Advantageous effect：
(1) active third-harmonic zero-sequence voltage matrix converter topological structure of the invention, bus current radio-frequency component is filtered out,
It solves the problems, such as that busbar high-frequency current causes input filter to shake with current break when low frequency inductance current switching, inputs
Distortion at electric current sector switch has obtained effective inhibition.
(2) active third-harmonic zero-sequence voltage matrix converter topological structure of the invention, due to being directly filtered to busbar,
Current ripples are obviously reduced when input current is equal to bus current.
(3) active third-harmonic zero-sequence voltage matrix converter topological structure of the invention increases two filtering on busbar
Inductance and a filter capacitor reduce three filter capacitors of input side, and increased device volume weight is smaller, therefore generally
Reduce volume, the weight of system.
(4) active third-harmonic zero-sequence voltage matrix converter of the invention improves topological structure, when increasing damping resistance, system
It responds faster, non-overshoot；It is still overdamp system when being not added with damping resistance, there is stronger stability.
(5) active third-harmonic zero-sequence voltage matrix converter of the invention improves topological structure, only need to change inductance and capacitance
Position, size, and it is not necessary to modify the control strategy of original topology, very simple is effective.
Description of the drawings
Fig. 1 is existing active third-harmonic zero-sequence voltage matrix converter topological structure；
Fig. 2 is provided by the invention a kind of can to improve active third-harmonic zero-sequence voltage matrix converter input current waveform
Topological structure (without hindrance buffer resistance)；
Fig. 3 is provided by the invention a kind of can to improve active third-harmonic zero-sequence voltage matrix converter input current waveform
Topological structure (contains damping resistance)；
Fig. 4 is the bi-directional switch structure figure that the present invention uses；
Fig. 5 is the input current simulation result pair of topological structure provided by the invention (without hindrance buffer resistance) and former topological structure
Than figure；
Fig. 6 is topological structure provided by the invention in without hindrance buffer resistance and dynamic characteristic simulation when having damping resistance
Comparison diagram.
Specific implementation mode
Below with reference to attached drawing, technical scheme of the present invention and advantageous effect are described in detail.
Active third-harmonic zero-sequence voltage matrix converter proposed by the present invention improves topological structure as shown in attached drawing 2 and attached drawing 3.
Three-phase alternating-current supply is connected on the three-phase input end of voltage selector by input filter, and the both ends x, z of voltage selector IVS are logical
DC terminal p, n that busbar filter is connected to current source inverter CSI is crossed, the ends y are connected to two-way opened by third-harmonic zero-sequence voltage circuit
It closes, three-phase alternating current loads the three-phase alternating current output end that current source inverter CSI is connected to by output inductor.
Busbar filter in attached drawing 2 includes two filter inductance Lx、LzWith a filter capacitor Cpn.Filter inductance Lx、Lz
It is connected on the both ends x, z of voltage selector IVS outputs respectively, and is separately connected the both ends DC side p, n of current source inverter CSI,
Filter capacitor CpnIt is connected across the both ends DC side p, n of current source inverter CSI.Design busbar filter in this way can be directly to mother
Line is filtered, if Li, i=x, z, with CpnMeet following formula：
Wherein ωnFor bus current harmonic wave angular frequency, (for active third-harmonic zero-sequence voltage matrix converter, bus current is humorous
Wave be distributed in inverter switching frequency and its again for several times near), Li, i=x, z and CpnRespectively busbar filter inductance and filtering
Capacitance, then busbar filter inductance to the impedance of bus current harmonic wave will be far longer than busbar filter capacitor, therefore bus current
Radio-frequency component largely flows to busbar filter capacitor, and flows to voltage selector IVS output x, the radio-frequency component of the electric current at the both ends z
Seldom.In this way, the three end x of voltage selector IVS, y, z electric currents have been subjected to filtering, therefore in sector switch, input side two
The alternate change of current can't cause the mutation of input current, the distortion of input current sector switch fundamentally to be inhibited.Separately
Outside, due to being directly filtered to busbar, filter effect, which is better than, is filtered three-phase input current.Attached drawing 5 is attached drawing 1 and attached
Topological structure simulation result comparison in Fig. 2, input current THD are reduced to 1.34% from 3.37%.
Attached topological structure shown in Fig. 2 increases two inductance and a capacitance on busbar, subtracts relative to attached drawing 1
Three capacitances for having lacked input side, from the quantity of device for there is no reducing, but increased capacitance only plays a filtering role,
Take the capacitance of very little that can also achieve the effect that hospital bus bar high-frequency current, therefore generally system bulk, weight decrease.
When without hindrance buffer resistance, system damping coefficient is less than normal, and stability is poor, therefore uses the common passive resistance of filter design
Buddhist nun's mode, in busbar filter inductance both ends parallel connection damping resistance to enhance the stability of system.As shown in Fig. 3, damping resistance
Rx、RzIt is connected in parallel on filter inductance Lx、LzBoth ends.At busbar filter inductance both ends, larger damping resistance in parallel can reach enhancing
The purpose of system stability, the power very little that resistance itself consumes, by high-frequency current it is seldom, to input current waveform quality
Influence it is very limited.Attached drawing 6 is the dynamic characteristic simulation comparison of attached drawing 2 and attached topological structure shown in Fig. 3.
Attached topological structure shown in Fig. 2, three two-way switch are four-quadrant switches, can flow through bidirectional current, can also hinder
Disconnected bi-directional voltage.The bi-directional switch structure that the present invention uses is as shown in Fig. 4, and each two-way switch is by two wholly-controled devices
(including body diode) cascode grade connects to be formed.The such two-way switch of selection can reduce the quantity of isolation drive power supply, simplify
The design of driving circuit reduces circuit stray inductance.
Attached topological structure shown in Fig. 2 need to only be modified the size of capacitor and inductor, position, without modification
The control strategy of former topology.The x of voltage selector IVS, y, the ends z select the maximal term, interphase, minimum of input voltage respectively
Phase, harmonic injection circuit to the closed-loop control of harmonic injection inductive current by achieving the purpose that input current sine and PFC, electricity
Flow pattern inverter uses carrier modulation strategy.
It, can according to the technique and scheme of the present invention and its hair it is understood that for those of ordinary skills
Bright design is subject to equivalent substitution or change, and all these changes or replacement should all belong to the guarantor of appended claims of the invention
Protect range.
Example the above is only the implementation of the present invention is not intended to limit the scope of the invention, every to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills
Art field, is included within the scope of the present invention.
Claims (7)
1. active third-harmonic zero-sequence voltage matrix converter input current waveform optimizes topological structure, including it is three-phase alternating-current supply, defeated
Enter filter, voltage selector (IVS), busbar filter, third-harmonic zero-sequence voltage circuit, current source inverter (CSI), three intersections
Current load, output inductor；The voltage selector includes rectification stage and three two-way switch, and rectification stage includes full-control type device
Three bridge arms of part composition, the third-harmonic zero-sequence voltage circuit include the y bridge arms and a harmonic injection of wholly-controled device composition
Current filtering inductance (Ly), it is characterised in that：The topological structure is equipped with busbar filter, the input filter on busbar
Including three input filter inductance.
2. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as described in claim 1
Structure, it is characterised in that：The three-phase alternating-current supply is connected on the three-phase input end of voltage selector, voltage choosing by input filter
The both ends x, z for selecting device (IVS) are connected to DC terminal p, n of current source inverter (CSI), the y bridges by the busbar filter
Arm end is connected to two-way switch by third-harmonic zero-sequence voltage circuit, and it is inverse that three-phase alternating current load by output inductor is connected to current mode
Become the three-phase alternating current output end of device (CSI).
3. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as described in claim 1
Structure, it is characterised in that：
The busbar filter includes two busbar filter inductance (Lx、Lz) and filter capacitor (Cpn)；
Busbar filter inductance (the Lx、Lz) it is connected on the both ends x, z of voltage selector (IVS) output respectively, and it is separately connected electric current
The both ends DC side p, n of type inverter (CSI), filter capacitor (Cpn) it is connected across DC side p, n two of current source inverter (CSI)
End.
4. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as claimed in claim 3
Structure, it is characterised in that：The busbar filter further includes two damping resistance (Rx、Rz), the damping resistance (Rx、Rz) respectively
It is connected in parallel on filter inductance (Lx、Lz) both ends.
5. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as described in claim 1
Structure, it is characterised in that：
The input filter includes three input filter inductance, connects the three of three-phase input power supply and voltage selector (IVS)
Phase input terminal.
6. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as described in claim 1
Structure, it is characterised in that：
The voltage selector (IVS) includes rectification stage and three two-way switch, and rectification stage includes the three of wholly-controled device composition
A bridge arm, each two-way switch are made of two wholly-controled device cascode grades, one individual two of each wholly-controled device inverse parallel
Pole pipe.
7. a kind of active third-harmonic zero-sequence voltage matrix converter input current waveform optimization topology knot as described in claim 1
Structure, it is characterised in that：
The third-harmonic zero-sequence voltage circuit includes the bridge arm and a harmonic injection current filtering inductance of wholly-controled device composition
(Ly), y bridge arms are connected across the both ends DC side p, n of current source inverter (CSI), harmonic injection current filtering inductance (Ly) connection y
Bridge arm and two-way switch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810093390.XA CN108390572B (en) | 2018-01-31 | 2018-01-31 | Input current waveform optimization topological structure of active third harmonic injection matrix converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810093390.XA CN108390572B (en) | 2018-01-31 | 2018-01-31 | Input current waveform optimization topological structure of active third harmonic injection matrix converter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108390572A true CN108390572A (en) | 2018-08-10 |
| CN108390572B CN108390572B (en) | 2020-05-19 |
Family
ID=63074305
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810093390.XA Active CN108390572B (en) | 2018-01-31 | 2018-01-31 | Input current waveform optimization topological structure of active third harmonic injection matrix converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108390572B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111293893A (en) * | 2020-02-26 | 2020-06-16 | 湖南人文科技学院 | Three-phase modular isolation matrix converter topological structure |
| CN112186771A (en) * | 2020-10-09 | 2021-01-05 | 北京航空航天大学 | Electric energy router based on matrix converter and electric energy routing method |
| CN113381621A (en) * | 2021-07-28 | 2021-09-10 | 南京航空航天大学 | Injection current control device of hybrid active third harmonic injection matrix converter |
| CN114865983A (en) * | 2022-06-02 | 2022-08-05 | 南京航空航天大学 | Three-phase alternating current speed regulation system for multiplexing excitation winding |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6154378A (en) * | 1998-04-29 | 2000-11-28 | Lockheed Martin Corporation | Polyphase inverter with neutral-leg inductor |
| CN106208735A (en) * | 2016-08-24 | 2016-12-07 | 中南大学 | The matrix converter of a kind of third-harmonic zero-sequence voltage and control method |
-
2018
- 2018-01-31 CN CN201810093390.XA patent/CN108390572B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6154378A (en) * | 1998-04-29 | 2000-11-28 | Lockheed Martin Corporation | Polyphase inverter with neutral-leg inductor |
| CN106208735A (en) * | 2016-08-24 | 2016-12-07 | 中南大学 | The matrix converter of a kind of third-harmonic zero-sequence voltage and control method |
Non-Patent Citations (2)
| Title |
|---|
| HYUNJAE YOO ET AL: "A New Circuit Design and Control to Reduce Input Harmonic Current for a Three-phase AC Machine Drive System having a very Small DC-link Capacitor", 《2010 TWENTY-FIFTH ANNUAL IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION (APEC)》 * |
| LUKAS SCHRITTWIESER ET AL: "Novel SWISS Rectifier Modulation Scheme Preventing Input Current Distortions at Sector Boundaries", 《IEEE TRANSACTIONS ON POWER ELECTRONICS》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111293893A (en) * | 2020-02-26 | 2020-06-16 | 湖南人文科技学院 | Three-phase modular isolation matrix converter topological structure |
| CN112186771A (en) * | 2020-10-09 | 2021-01-05 | 北京航空航天大学 | Electric energy router based on matrix converter and electric energy routing method |
| CN113381621A (en) * | 2021-07-28 | 2021-09-10 | 南京航空航天大学 | Injection current control device of hybrid active third harmonic injection matrix converter |
| CN114865983A (en) * | 2022-06-02 | 2022-08-05 | 南京航空航天大学 | Three-phase alternating current speed regulation system for multiplexing excitation winding |
| CN114865983B (en) * | 2022-06-02 | 2023-04-18 | 南京航空航天大学 | Three-phase alternating current speed regulation system for multiplexing excitation winding |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108390572B (en) | 2020-05-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101517854B (en) | Voltage source converter station | |
| CN108390572A (en) | Active third-harmonic zero-sequence voltage matrix converter input current waveform optimizes topological structure | |
| CN102097793B (en) | Multi-current converter unified power quality conditioning device for power distribution system | |
| CN102130577B (en) | Window control circuit for power factor correction circuit | |
| CN102769291B (en) | Active power filter based on multiphase converter structure | |
| CN107332257A (en) | A kind of STATCOM and its control method | |
| CN106849726A (en) | Double droop control methods of three-phase four-leg inverter in parallel under uneven operating mode | |
| CN105932677A (en) | Harmonic suppression system with multi-level active power filter | |
| CN206620047U (en) | Interleaving PFC power conversion circuit | |
| CN105634319B (en) | A kind of more level Cascade H-Bridge Inverters with coupling inductance | |
| CN102291018B (en) | Single-phase rectifier with APFC (active power factor correction) circuit and alternating-current input voltage amplitude detection method thereof | |
| CN203645329U (en) | Improved LCL filter and inverter system | |
| CN205565742U (en) | Mixed electric power equalizer that passive zero sequence filtering technique and active filtering technique combine | |
| CN207166122U (en) | The protection device and micro-capacitance sensor of a kind of grounding transformer | |
| CN102969885A (en) | Additional-voltage-free zero voltage switch bridge-free power factor corrector and modulation method | |
| CN110071510A (en) | Single-phase hybrid active electric filter and its control method based on UPQC | |
| CN107453326A (en) | The protection device and micro-capacitance sensor of a kind of grounding transformer | |
| CN108683345A (en) | A kind of double Buck/Boost current transformers of three-phase modified based on SiC diodes | |
| CN103944244A (en) | PWM electric vehicle charging power supply and charging station based on PWM charging power supply | |
| CN208707547U (en) | A kind of double Buck/Boost current transformers of three-phase modified based on SiC diode | |
| CN110071507A (en) | Single-phase series-parallel hybrid active electric filter | |
| CN212784780U (en) | Active power filter based on two-level branch circuit parallel connection | |
| CN107863893A (en) | The level rectifying system of midpoint self-balancing three | |
| CN205901299U (en) | Active electric power balance robot | |
| CN204244065U (en) | Filter circuit and three-phase inverter |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |