CN204031005U - The T-shaped inverter of a kind of Z source three level - Google Patents
The T-shaped inverter of a kind of Z source three level Download PDFInfo
- Publication number
- CN204031005U CN204031005U CN201420401743.5U CN201420401743U CN204031005U CN 204031005 U CN204031005 U CN 204031005U CN 201420401743 U CN201420401743 U CN 201420401743U CN 204031005 U CN204031005 U CN 204031005U
- Authority
- CN
- China
- Prior art keywords
- source
- level
- inverter
- brachium pontis
- shaped inverter
- 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.)
- Expired - Fee Related
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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/487—Neutral point clamped inverters
Landscapes
- Inverter Devices (AREA)
Abstract
The utility model relates to the T-shaped inverter of a kind of Z source three level, and this topology has the identical characteristic of boosting of Z source network three level neutral-point-clamped (NPC) inverter, but switching device number used is less, and efficiency is higher.Compare with the T-shaped inverter of three level, topology of the present utility model not only can realize lifting/voltage reducing function, and allows upper and lower bridge arm direct pass, and reliability obviously increases, and the deadband eliminating time, prevents wave distortion; Compare with Z source two-level inverter, output voltage has midpoint potential, therefore and high-frequency harmonic little, required filter is less, because three level are than the more approaching sine wave of two level, so switching frequency can reduce, switching loss is less; It adopts the method for in-phase voltage skew (phase disposition, PD) to control inverter, adopts and can reduce on-off times with the method, reduces switching loss, reduces harmonic wave of output voltage content.
Description
Technical field
The utility model relates to the T-shaped inverter of a kind of Z source three level.
Background technology
Along with the continuous lifting that develops rapidly and efficiency is required of distributed power source, the efficiency that improves the quality of power supply, minimizing harmonic pollution, raising electricity generation system is the key issue of distributed power source development.Three-level inverter has the advantages such as few, the withstand voltage height of harmonic wave, switch stress is little, electromagnetic interference (Electro Magnetic Interference, EMI) is few than traditional two-level inverter and at distributed power source and micro-electrical network field, is used widely.Yet the output voltage for fuel cell, photovoltaic cell distributed power supply is not constant, cannot realizes the unsteady flow function of wider direct voltage scope and obtain higher ac output voltage.In order to meet the wider voltage range of DC bus, researcher has added DC/DC converter, adopts two-layer configuration.Yet this converter not only needs more power device, also produce in the course of the work a large amount of switching losses, reduce system effectiveness.In order to reduce the impact on system effectiveness of the switching loss that causes because of DC/DC converter, adopting the two-level inverter of Z source network is a kind of desirable selection.
Z source two-level inverter is widely used at new energy fields such as photovoltaic DC-to-AC converter, energy storage, electric automobile, fuel cells.But along with developing rapidly of distributed power source, improve the requirements such as the quality of power supply and power grade and receive much concern.Z source multi-electrical level inverter can address the above problem.And Z source three level neutral-point-clampeds (neutral point clamped, NPC) inverter is widely used in regenerative resources such as photovoltaic DC-to-AC converter, wind-driven generator, fuel cells, and by one, independently DC power supply, two DC side dividing potential drop electric capacity, a Z source network and three level NPC inverter circuits form for it.The introducing of Z source network makes to lead directly to becomes a kind of normal operating state, and by controlling straight-through duty ratio, Z source three level NPC inverters can be realized boost function, and need not control Dead Time, prevent inversion wave distortion.Bridge arm direct pass can not cause the damage of power device, and reliability obviously increases.Therefore, Z source three level NPC inverters are with the obvious advantage with respect to traditional three level NPC inverters, and prospect is very wide.But Z source three level NPC inverters need passive device too many, can produce a large amount of power losss, can cause like this efficiency of system low.Efficiency and the quality of power supply are that assurance regenerative resource and micro-electrical network are reliable, stable, the guarantee of economical operation.Therefore, study the topological structure of a kind of efficiency and quality of power supply optimum most important.And for the T-shaped inverter of three level, efficiency and the quality of power supply are all better with respect to Z source three level NPC and Z source two-level inverter, but the output voltage output for fuel cell, photovoltaic cell distributed power supply is non-constant, cannot realize wide output voltage, and because the reason in dead band causes harmonic wave very large.
Utility model content
In order to address the above problem, the utility model proposes the T-shaped inverter of a kind of Z source three level, it adopts in-phase voltage skew (phase disposition, PD) control mode, compare reverse voltage offset modulation (alternative phase opposition disposition, APOD) method, can reduce on-off times, reduces switching loss.
For achieving the above object, the utility model adopts following technical scheme:
The T-shaped inverter of Z source three level, comprises three-phase brachium pontis in parallel, and every phase brachium pontis comprises the IGBT pipe of two series connection, the different IGBT pipe of mid point one side series connection both direction of each phase brachium pontis, and opposite side is connected with resistance through filter; After connecting Z source network, each brachium pontis input of parallel connection accesses input voltage source; Input voltage source two ends are parallel with the electric capacity of two series connection, and two electric capacity junctions connect one end of the both direction different I GBT pipe of every brachium pontis, and each IGBT pipe drives by control circuit.
Described Z source network comprises two inductance and electric capacity, two inductance are connected on respectively the junction of input voltage source two ends and three-phase brachium pontis, inductance is in series with diode with the side that is connected of input voltage source, and two diode reverse, one end of two electric capacity connects respectively the junction of diode and inductance, and the other end is connected to the junction of another road inductance and three-phase brachium pontis.
Described filter is LC filter circuit, and electric capacity common end grounding wherein.
Described control circuit comprises protective circuit, drive circuit, sampling modulate circuit; sampling modulate circuit connects DSP module; DSP module and protective circuit two-way communication, DSP module connects drive circuit, and in drive circuit output pwm signal driving brachium pontis, IGBT pipe opening and turn-offing.
The three-phase voltage value size of the direct voltage of described sampling modulate circuit Gather and input voltage source, direct current, Z source network capacitance voltage and filter output.
The beneficial effects of the utility model are:
1, with respect to the T-shaped inverter of three level, the Z source T-shaped inverter of three level not only can be realized and boosting, and can not cause the damage of power device due to straight-through, and reliability obviously increases, and the deadband eliminating time, prevents wave distortion;
2 compare with Z source two-level inverter, and the Z source T-shaped inverter output voltage of three level has midpoint potential, therefore and high-frequency harmonic little, required filter is less, because three level are than the more approaching sine wave of two level, so switching frequency can reduce, and switching loss is less;
3 compare with Z source three level NPC inverters, and the Z source T-shaped inverter of three level has reduced component number, and conduction loss is lower, and efficiency is higher;
4, there is the advantages such as high power, waveform quality be good, extensive in renewable energy source domain prospects such as photovoltaic generating system, wind generator system, fuel cells.
Accompanying drawing explanation
Fig. 1 is the T-shaped inverter structure figure of three level;
Fig. 2 is the T-shaped inverter modulating wave of three level, carrier waveform;
Fig. 3 a is a kind of state fundamental diagram of the T-shaped inverter of three level;
Fig. 3 b is a kind of state fundamental diagram of the T-shaped inverter of three level;
Fig. 3 c is a kind of state fundamental diagram of the T-shaped inverter of three level;
Fig. 4 is the utility model system construction drawing;
Fig. 5 a is the T-shaped inverter of Z source three level equivalent circuit diagram under non-pass-through state;
Fig. 5 b is the T-shaped inverter of Z source three level equivalent circuit diagram under upper pass-through state;
Fig. 5 c is the T-shaped inverter of Z source three level equivalent circuit diagram under lower pass-through state;
Fig. 5 d is that three level T-shaped inverter in Z source is in complete straight-through lower state equivalent circuit diagram.
Fig. 6 a boosts and inversion control for adopting the method for reverse voltage offset modulation (alternative phase opposition disposition, APOD-SPWM) to realize the Z source T-shaped inverter of three level;
Fig. 6 b boosts and inversion control for adopting the control method of in-phase voltage skew (phase disposition, PD-SPWM) to realize the Z source T-shaped inverter of three level;
Fig. 7 is the operation waveform of three level T-shaped inverter in Z source in straight-through situation and in non-straight-through situation;
The operation waveform that Fig. 8 is the T-shaped inverter of Z source three level in complete straight-through and upper and lower straight-through situation;
The operation waveform that Fig. 9 is the Z source T-shaped inverter of three level and Z source three level NPC inverters in non-straight-through and upper and lower straight-through situation;
Figure 10 is Z source three level NPC inverter structure figure;
Figure 11 is the control circuit figure of the T-shaped inverter in Z source.
Embodiment
Below in conjunction with accompanying drawing and embodiment, the utility model is described further.
Fig. 1 is the T-shaped inverter structure figure of three level, and main circuit is the T-shaped inverter of three level, and input voltage is connected with electric capacity, and DC bus capacitor mid point is connected with IGBT pipe 3, and filter is LC filter.System output is connected with load.
For the T-shaped inverter of three level, adopt the method for APOD-SPWM, can make final output voltage comprise a large amount of harmonic waves, affect the waveform quality of output voltage.And the mode that adopts PD-SPWM is controlled PWM output and can be improved voltage waveform quality.Therefore the utility model adopts the method for PD-SPWM to realize the control to the T-shaped inverter of three level.
The coherent signal that signal conditioning circuit records Hall element is nursed one's health, and obtains the analog signal that sample circuit can receive.The sampling of AD converter is controlled by DSP with conversion, and conditioned analog signal is converted to digital quantity.The processing of digital signal and SPWM control, PWM produces by DSP and realizes, and the final pwm signal generating is given drive circuit and gone to control opening and turn-offing of IGBT pipe.
Fig. 2 is SPWM modulating wave, carrier waveform, and Fig. 3 is three level T-shaped inverter Converting Unit structure and circuit theory diagrams.Concrete control mode is as follows:
Modulating wave is three-phase sine-wave,
u
a＝sinωt
u
b＝sin(ωt-120°)
u
c＝sin(ωt-240°)；
Carrier wave for differing the triangular wave of 180 ° in phase place.
The a of take is example mutually, and effluent is for just to the right to suppose electric current, and on off sequence generating mode is as follows:
If Ua>CA1 and Ua>CA2, on off sequence (Ua1, Ua2, Ua3, Ua4)=(1,1,0,0)=P.From Fig. 3 a, when i>0, when Ua1 opens, although Ua2 is open-minded, do not have electric current to flow through Ua2, Ua3, Ua4 turn-offs.When i<0, Ua1, Ua2, Ua3, Ua4 turn-offs.Ua0=Vin/2. now
If Ua<CA1 and Ua<CA2, on off sequence (Ua1, Ua2, Ua3, Ua4)=(0,0,1,1)=N.From Fig. 3 c, when i<0, when Ua4 opens, although Ua3 is open-minded, do not have electric current to flow through Ua3, Ua, 1, Ua2 turn-offs.When i>0, Ua1, Ua2, Ua3, Ua4 turn-offs.So Ua0=-Vin/2.
If Ua<CA1 and Ua>CA2, on off sequence (Ua1, Ua2, Ua3, Ua4)=(0,1,1,0)=O.From Fig. 3 b, when i>0, Ua2 is open-minded, Ua1, and Ua3, Ua4 turn-offs.So Ua0=0.
If Ua<CA1 and Ua>CA2, on off sequence (Ua1, Ua2, Ua3, Ua4)=(0,1,1,0)=O.From Fig. 3 b, when i<0, Ua3 is open-minded, Ua1, and Ua2, Ua4 turn-offs.So Ua0=0.
As shown in Figure 4, each brachium pontis comprises the IGBT pipe of two series connection, and the mid point left side of each phase brachium pontis connects the IGBT pipe that both direction is contrary, and the mid point right side of each phase brachium pontis is connected with corresponding resistor through filter; The a pair of capacitor C 1, the capacitor C 2 that at each brachium pontis input of parallel connection, are parallel with series connection, the left side of capacitor C 1, capacitor C 2 is connected with input voltage; The right side of capacitor C 1, capacitor C 2 is connected with Z source network, and the contrary IGBT pipe of both direction of each brachium pontis is connected with the mid point of capacitor C 1, C2.Fig. 5 a is the T-shaped inverter of Z source three level equivalent circuit diagram under non-pass-through state; Fig. 5 b is the T-shaped inverter of Z source three level equivalent circuit diagram under upper pass-through state; Fig. 5 c is the T-shaped inverter of Z source three level equivalent circuit diagram under lower pass-through state; Fig. 5 d is that three level T-shaped inverter in Z source is in complete straight-through lower state equivalent circuit diagram.Known by the derivation of equation, when sensitizing factor B=1, the Z source T-shaped inverter of three level is operated in traditional decompression mode; When sensitizing factor B>1, be operated in boost mode.
Fig. 6 a is the APOD-SPWM modulator approach of conventional inverter and Z source cascaded inverter; The boosting rectifier control of the T-shaped inverter of Z source three level need to increase extra pass-through state, pass-through state add the normal inversion that can not change inverter, therefore need to join disarmed state { O, O, O} is upper, and this state can boosted output voltages, but on not impact of inverter output loading.In order to obtain the pass-through state of T0 ', need to, at vertical direction translation the T0 '/T of modulating wave, obtain in the horizontal direction the straight-through time.At any time, Umax (Ua to modulation signal, Ub, maximum in Uc) increase the vertical shift of T0 '/T, simultaneously to the Umin of modulation signal (Ua, Ub, minimum value in Uc) reduce the vertical shift of T0 '/T, yet keep the Umid (Ua, Ub, the median in Uc) of modulation signal not change.Thereby obtain the needed straight-through duty ratio of the T-shaped inverter of Z source three level.
Fig. 6 b is the PD-SPWM modulator approach of conventional inverter and Z source cascaded inverter; With respect to APOD-SPWM modulator approach, the output voltage that PD-SPWM modulator approach can obtain.For the T-shaped inverter of Z source three level, the injection of pass-through state can not exert an influence to the output voltage of brachium pontis, and for in-phase voltage, skew is controlled, { O} state can not produce complete straight-through for O, O, therefore only have upper straight-through and lower leading directly to, and upper and lower straight-through can only being created in equivalent zero vector.Wherein, { O} state refers to that the IGBT pipe of three-phase brachium pontis in parallel is all in { O} state for O, O.{ Continuity signal of four IGBT pipes that O} state is this phase brachium pontis is respectively (0,1,1,0); { Continuity signal of four IGBT pipes that N} state is this phase brachium pontis is respectively (0,0,1,1); { Continuity signal of four IGBT pipes that P} state is this phase brachium pontis is respectively (1,1,0,0).
Upper leading directly to can only occur in { O}, { in the action time of the equipollent vectors of N} state, lower leading directly to can only occur in { O}, { in the action time of P} state equipollent vectors, selector switch state is changed minimum brachium pontis and is produced straight-through, at any time, Umax to modulation signal, be Ua, Ub, maximum in Uc, the vertical shift that increases 0.5T0/T produces upper straight-through, Umin to modulation signal simultaneously, Ua, Ub, minimum value in Uc, the vertical shift that reduces 0.5T0/T produces lower straight-through, the Umid that keeps modulation signal, Ua, Ub, median in Uc is constant, obtain the needed straight-through duty ratio of the T-shaped inverter of Z source three level, finally the pwm signal obtaining is delivered to drive circuit.
Fig. 7 is the waveform that PD-SPWM method is controlled lower straight-through time T 0=0 and T0=0.2.During straight-through time T 0=0, setting modulation degree M is 0.8.What in figure, export successively is phase voltage, phase current, line voltage, Z source network capacitance voltage, Vdc voltage.The Z source T-shaped inverter of three level does not boost, so the peak value of line voltage equals 200V.During straight-through time T 0=0.2, by the known sensitizing factor B=1.66 of formula, therefore theoretical phase voltage value is 159*1.66/1.732=151V, and actual measured value is 140V.By formula, can obtain theoretical boost value Vdc is 332V, and actual measured value is 324V.Electric current is not subject to the impact of through connect signal and distorts.The capacitance voltage of Z source network can obtain 266V by correlation formula, and actual measured value is 265V.Vdc voltage is realized and being boosted and invert function to 324V variation at 162V in addition.Simulation result shows that the Z source T-shaped inverter of three level can make line voltage be raised to the value of setting and not affect the waveform quality of output current.
Fig. 8 is the impact on output voltage waveforms quality under APOD-SPWM method and PD-SPWM method are controlled.Suppose that APOD-SPWM method adopts the parameter the same with PD-SPWM method.Under APOD-SPWM method, setting modulation degree M is 0.8, and the time T 0 ' of straight-through duty ratio is 0.2.Under PD-SPWM method, setting modulation degree M is 0.8, and the time T 0 of straight-through duty ratio is 0.2.By simulation result, can be found out, adopt the advantages such as PD-SPWM method has switching loss and harmonic distortion is little.
Fig. 9 is that Z source three level NPC inverters and the Z source T-shaped inverter of three level adopt PD-SPWM method to carry out simulation comparison.From figure, table 1 can find out, three level T-shaped inverter in Z source is with Z source three level NPC inverters under identical modulation strategy, harmonic wave is little, waveform quality is suitable.
Under table 1 PD modulation strategy, harmonic ratio
| ? | The T-shaped inverter in Z source | Z source NPC inverter |
| Straight-through | 0.63％ | 0.65％ |
| Non-straight-through | 0.47％ | 0.49％ |
Figure 10 is the structure chart of Z source three level NPC.
Figure 11 is the control circuit figure of the T-shaped inverter in Z source; Control circuit comprises protective circuit, drive circuit and sampling modulate circuit, sampling modulate circuit comprises three-phase voltage U a, Ub, the Uc of direct voltage Vin, Z source capacitance voltage Vzc, direct current Idc and filter output, signal conditioning circuit and control had/under-voltage protection of voltage and overcurrent protection; In drive circuit output pwm signal driving brachium pontis, IGBT pipe opening and turn-offing.
Therefore, adopt PD modulation strategy can realize boosting and invert function of the T-shaped inverter of Z source three level, and with respect to Z source three level NPC inverters, conduction loss is lower, efficiency is high, and waveform quality is suitable.This topology inverter has a extensive future at renewable energy source domains such as photovoltaic generating system, wind generator system, fuel cells.
Although above-mentioned, by reference to the accompanying drawings embodiment of the present utility model is described; but the not restriction to the utility model protection range; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various modifications that creative work can make or distortion still in protection range of the present utility model.
Claims (5)
1. the T-shaped inverter of Z source three level, is characterized in that: comprise three-phase brachium pontis in parallel, every phase brachium pontis comprises the IGBT pipe of two series connection, the different IGBT pipe of mid point one side series connection both direction of each phase brachium pontis, and opposite side is connected with resistance through filter; After connecting Z source network, each brachium pontis input of parallel connection accesses input voltage source; Input voltage source two ends are parallel with the electric capacity of two series connection, and two electric capacity junctions connect one end of the both direction different I GBT pipe of every brachium pontis, and each IGBT pipe drives by control circuit.
2. the T-shaped inverter of a kind of Z as claimed in claim 1 source three level, it is characterized in that: described Z source network comprises two inductance and electric capacity, two inductance are connected on respectively the junction of input voltage source two ends and three-phase brachium pontis, inductance is in series with diode with the side that is connected of input voltage source, and two diode reverse, one end of two electric capacity connects respectively the junction of diode and inductance, and the other end is connected to the junction of another road inductance and three-phase brachium pontis.
3. the T-shaped inverter of a kind of Z as claimed in claim 1 source three level, is characterized in that: described filter is LC filter circuit, and electric capacity common end grounding wherein.
4. the T-shaped inverter of a kind of Z as claimed in claim 1 source three level; it is characterized in that: described control circuit comprises protective circuit, drive circuit, sampling modulate circuit; sampling modulate circuit connects DSP module; DSP module and protective circuit two-way communication; DSP module connects drive circuit, and in drive circuit output pwm signal driving brachium pontis, IGBT pipe opening and turn-offing.
5. the T-shaped inverter of a kind of Z as claimed in claim 4 source three level, is characterized in that: the three-phase voltage value size of the direct voltage of described sampling modulate circuit Gather and input voltage source, direct current, Z source network capacitance voltage and filter output.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420401743.5U CN204031005U (en) | 2014-07-18 | 2014-07-18 | The T-shaped inverter of a kind of Z source three level |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420401743.5U CN204031005U (en) | 2014-07-18 | 2014-07-18 | The T-shaped inverter of a kind of Z source three level |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204031005U true CN204031005U (en) | 2014-12-17 |
Family
ID=52070829
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420401743.5U Expired - Fee Related CN204031005U (en) | 2014-07-18 | 2014-07-18 | The T-shaped inverter of a kind of Z source three level |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204031005U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104092400A (en) * | 2014-07-18 | 2014-10-08 | 山东大学 | Z-source three-level T-type inverter and modulating method thereof |
| CN104167947A (en) * | 2014-07-18 | 2014-11-26 | 山东大学 | Z-source three-level T-type inverter and neutral-point balance control method thereof |
| CN104698860A (en) * | 2015-02-05 | 2015-06-10 | 北京理工大学 | Conduction electromagnetic interference simulation system for alternating-current motor inverter power circuit of electric car |
| CN105846703A (en) * | 2016-05-13 | 2016-08-10 | 东北电力大学 | Three-phase T type three-level inverter sine pulse-width modulation strategy |
-
2014
- 2014-07-18 CN CN201420401743.5U patent/CN204031005U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104092400A (en) * | 2014-07-18 | 2014-10-08 | 山东大学 | Z-source three-level T-type inverter and modulating method thereof |
| CN104167947A (en) * | 2014-07-18 | 2014-11-26 | 山东大学 | Z-source three-level T-type inverter and neutral-point balance control method thereof |
| CN104167947B (en) * | 2014-07-18 | 2017-04-12 | 山东大学 | Z-source three-level T-type inverter and neutral-point balance control method thereof |
| CN104698860A (en) * | 2015-02-05 | 2015-06-10 | 北京理工大学 | Conduction electromagnetic interference simulation system for alternating-current motor inverter power circuit of electric car |
| CN104698860B (en) * | 2015-02-05 | 2020-05-12 | 北京理工大学 | Conducted electromagnetic interference simulation system of power loop of alternating current motor inverter of electric automobile |
| CN105846703A (en) * | 2016-05-13 | 2016-08-10 | 东北电力大学 | Three-phase T type three-level inverter sine pulse-width modulation strategy |
| CN105846703B (en) * | 2016-05-13 | 2018-12-11 | 东北电力大学 | A kind of three-phase T-type three-level inverter Sinusoidal Pulse Width Modulation strategy |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204103797U (en) | The T-shaped inverter of a kind of accurate Z source three level | |
| CN104092399A (en) | Standard Z source three-level T-shaped inverter and SVPWM method thereof | |
| CN104092400A (en) | Z-source three-level T-type inverter and modulating method thereof | |
| CN102005958B (en) | Photovoltaic grid-connected three-level inverter | |
| CN103532420B (en) | Dual-three-level online-topology switchable inverter | |
| CN103326606B (en) | A kind of one-phase five-level inverter | |
| CN108599604B (en) | Single-phase seven-level inverter and PWM signal modulation method thereof | |
| CN103036397B (en) | Single-level single-phase large-step-up-ratio cascade connection voltage type convertor of quasi impedance source | |
| CN105576982A (en) | Non-isolated DC transformer | |
| CN104167947B (en) | Z-source three-level T-type inverter and neutral-point balance control method thereof | |
| CN102361408A (en) | Non-isolated photovoltaic grid-connected inverter and switching control time sequence thereof | |
| CN104638971A (en) | Photovoltaic grid-connected inverter and control method thereof | |
| CN105978388A (en) | Single-phase voltage boosting-reducing type photovoltaic inverter capable of inhibiting current leakage and control method thereof | |
| CN204031005U (en) | The T-shaped inverter of a kind of Z source three level | |
| CN106452142B (en) | A kind of improvement modulation strategy suitable for Modular multilevel converter | |
| CN102946209A (en) | Single-stage three-phase large step-up ratio series voltage type quasi-impedance source inverter | |
| CN107134937A (en) | A kind of three level multiple-pulses output transformerless inverter circuit | |
| CN104767365A (en) | T type three-level DC/AC converter direct voltage ripple compensation system and method | |
| CN104811071A (en) | Photovoltaic inverter and passive decoupling restraining method based on non-isolated LCL filtering | |
| CN105281361A (en) | Five-level double-step down grid-connected inverter | |
| CN105186912A (en) | Two-stage non-isolated full-bridge grid-connected inverter | |
| CN112564526A (en) | Three-phase T-shaped three-level double-output inverter | |
| CN103312210A (en) | Three-phase four-wire type three-level photovoltaic grid-connected inverter | |
| CN105262361A (en) | Two-stage non-isolation photovoltaic grid-connected inverter and control method thereof | |
| CN103036398A (en) | Single-level single-phase large-step-up-ratio cascade connection voltage type convertor of quasi impedance source |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141217 Termination date: 20150718 |
|
| EXPY | Termination of patent right or utility model |