CN109687746A - The novel quasi- source Z three-level inverter and its invariable power grid-connection control system - Google Patents

The novel quasi- source Z three-level inverter and its invariable power grid-connection control system Download PDF

Info

Publication number
CN109687746A
CN109687746A CN201811590221.3A CN201811590221A CN109687746A CN 109687746 A CN109687746 A CN 109687746A CN 201811590221 A CN201811590221 A CN 201811590221A CN 109687746 A CN109687746 A CN 109687746A
Authority
CN
China
Prior art keywords
diode
source
grid
power
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.)
Pending
Application number
CN201811590221.3A
Other languages
Chinese (zh)
Inventor
程启明
沈磊
魏霖
王玉娇
程尹曼
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.)
Shanghai University of Electric Power
University of Shanghai for Science and Technology
Original Assignee
Shanghai University of Electric Power
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 Shanghai University of Electric Power filed Critical Shanghai University of Electric Power
Priority to CN201811590221.3A priority Critical patent/CN109687746A/en
Publication of CN109687746A publication Critical patent/CN109687746A/en
Pending legal-status Critical Current

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
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • 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
    • H02M7/53—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 using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/539—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency
    • H02M7/5395—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency by pulse-width modulation

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inverter Devices (AREA)

Abstract

The present invention relates to a kind of novel quasi- source Z three-level inverter and its invariable power grid-connection control systems, the structure of the novel quasi- source Z three-level inverter is in the case where identical straight-through duty ratio and DC input voitage, higher voltage output can be obtained, high voltage, powerful occasion are suitable for；Compared with traditional Z-source inverter, the switched inductors unit of addition, due to using unsymmetric structure, capacitor polarity is identical as electric power polarity.While obtaining high voltage output, the source Z capacitance voltage stress is reduced, protects Z source network topological, reduces capacitor volume, saved cost；Two level thoughts are expanded in three level, switching device voltage stress is reduced, the Waveform sine of output is higher, and filter uses LCL type, using the method for injecting passive damping, it is suppressed that resonance peak.Grid-connected time-harmonic wave aberration rate is lower, grid-connected excellent effect；Using power limitation control Grid-connected Control Strategy is simplified, so that inverter output power is adjustable controllable.

Description

The novel quasi- source Z three-level inverter and its invariable power grid-connection control system
Technical field
The present invention relates to a kind of inversion transformation technique, in particular to a kind of novel quasi- source Z three-level inverter and its invariable power are simultaneously Network control system.
Background technique
In recent years, with the fast development of micro-capacitance sensor technology and the extensive use of new energy, novel inverter topology and Its grid-connected control method becomes the hot spot of research.The it is proposed of Z-source inverter (Z-Source Inverter, ZSI) is so that up and down Bridge arm direct pass becomes normal condition, forms unique buck mechanism, increases security of system and electromagnetism interference.But There are limitations for existing Z-source inverter topology: the DC boosting factor is smaller, when output voltage is higher, it is necessary to when increasing straight-through Between, so that inverter is in harsh environments for a long time, to also increase capacitance voltage stress；Inrush current mistake Greatly, it is easily damaged inverter.Research thus is improved to ZSI topology, is had for the development of micro-capacitance sensor higher quality important Meaning.
Existing literature proposes a kind of topology for reducing Z source network capacitance voltage stress, and inhibits starting-impact, but effect of boosting Fruit is not improved.Also a kind of reduction system cost is proposed, it is suppressed that dash current, but boost capability does not have still It is improved.Also there is the special modified Z-source inverter for proposing to increase boost capability, but boost effect is unobvious.It will also open Powered-down sense technical application to the source Z topology in, symmetrical two level block of use, capacitance voltage stress remain unchanged very high, derailing switch The voltage strength that part is born is still very big.
In order to reduce influence of the grid-connected inverters to bulk power grid stability, it is necessary to analyze Grid-connected Control Strategy. Existing literature has using Dynamic Voltage Regulator and is adjusted with Static Var Compensator, but installation cost is high, and utilization rate is low； There are also the control system using multi-functional gird-connected inverter, influence of the phaselocked loop for power quality controlling link is avoided, but real Existing process can occupy more hardware space；Also there is the real power control strategy for proposing to use the quick harmonic carcellation of paralleling compensating device, But the influence of reactive power is not fully considered.
Summary of the invention
The problem of existing now the present invention be directed to Z-source inverter, propose a kind of novel quasi- source Z three-level inverter and Its invariable power grid-connection control system improves existing Z-source inverter structure, and proposes to simplify power limitation control strategy, The influence for fully considering reactive power, allows the novel quasi- source Z three-level inverter output power quickly track reference power. Network voltage can be supported by output reactive power when necessary, grid-connected current aberration rate is low, it can be achieved that unity power factor exports.
The technical solution of the present invention is as follows: a kind of novel quasi- source Z three-level inverter, including sequentially connected double direct currents Source, quasi- Z source network and three-level inverter, use 2 voltages for uin/ 2 DC power supply；Quasi- Z source network part is by 4 electricity Sense, 2 capacitors and 7 diode compositions, a uin/ 2 DC power supply positive outputs connect diode D1 anode and the one end inductance L1, and two Pole pipe D1 and inductance L3 is connected in series and tie point is D1 cathode, and inductance L1 concatenates connection with diode D3 and tie point is Diode D3 anode, in parallel after two series connections, i.e., diode D3 cathode is connect with the one end inductance L3, and diode D2 anode connects two Pole pipe D3 anode, diode D2 cathode connect diode D1 cathode；Diode D3 cathode, which is namely connected in parallel, a little meets diode D7 Anode, diode D7 cathode connect diode D4 anode and the one end inductance L2, and diode D4 is connected in series and connect with inductance L4 Point be D4 cathode, inductance L2 concatenate with diode D6 connection and tie point be diode D6 anode, two series connections after parallel connection, I.e. diode D6 cathode is connect with the one end inductance L4, and diode D5 anode connects diode D6 anode, and diode D5 cathode connects two poles Pipe D4 cathode；Capacitor C1 is connected in parallel on diode D1 anode and diode D7 cathode；Capacitor C2 is connected in parallel on diode D7 anode and two Pole pipe D6 cathode.
The quasi- Z-source inverter accesses power grid after filtering by LCL, invariable power grid-connection control system includes power control loop Three section, current control link and abc-dq transform part parts, grid-connected three-phase electricity is acquired by voltage and current acquisition module Press exWith electric current ix, x=a, b, c, three-phase voltage exRoute angular frequency, e are obtained by phaselocked loopx、ixPass through abc-dq with ω Transform part obtains d axis and q shaft voltage edqWith electric current idqInput power controlling unit；Given active and reactive reference power Pref、Qref, the reference current i of d axis, q axis is calculated by power control linkdref、iqref, then idref、iqrefInto electric current Controlling unit, with actual current d axis, q shaft current id、iqCompare, calculates the reference value u of d axis, q shaft voltagedref、uqref；Most Afterwards by dq-abc transform part, it is converted into three-phase voltage reference value uxref, as the input value of SVPWM, give at the same time Straight-through duty ratio D appropriate0Modulated signal is exported to inverter into SVPWM, SVPWM.
Grid power expression formula is injected in the power control link to simplify are as follows:
Quasi- Z-source inverter shaft voltage u after abc-dq is converted by the filtered voltage of LCLdAnd uqExpression formula are as follows:
Wherein ω is grid-connected route angular frequency, and R is grid-connected line resistance, and L is grid-connected line inductance.
The beneficial effects of the present invention are: the novel quasi- source the Z three-level inverter of the present invention and its invariable power cutting-in control system System, the structure of the novel quasi- source Z three-level inverter can obtain in the case where identical straight-through duty ratio and DC input voitage Higher voltage output is obtained, high voltage, powerful occasion are suitable for；Compared with traditional Z-source inverter, the switched inductors of addition Due to using unsymmetric structure in unit, capacitor polarity is identical as electric power polarity.While obtaining high voltage output, Z is reduced Source capacitance voltage stress protects Z source network topological, reduces capacitor volume, saved cost；Two level thoughts are expanded to In three level, switching device voltage stress is reduced, the Waveform sine of output is higher, has saved filter cost, filter Using LCL type, using the method for injecting passive damping, it is suppressed that resonance peak.Grid-connected time-harmonic wave aberration rate is lower, grid-connected effect It is excellent；Using power limitation control Grid-connected Control Strategy is simplified, so that inverter output power is adjustable controllable.And it sufficiently examines Consider the influence of reactive power, it may be necessary to support Network Voltage Stability, improve grid power quality.
Detailed description of the invention
Fig. 1 is the topology diagram of the quasi- source Z three-level inverter of the present invention；
Fig. 2 a is the SVPWM state assignment figure of conventional voltage source three-level inverter；
Fig. 2 b is the SVPWM state assignment figure of the quasi- source Z three-level inverter of the present invention；
Fig. 3 is the LCL type filter used figure compared with the Bode diagram of L-type filter of the invention；
Fig. 4 is the grid-connection control system figure of novel quasi- Z-source inverter of the present invention；
Fig. 5 a is the inductive current waveform diagram of the novel quasi- source Z three-level inverter output of the present invention；
Fig. 5 b is the inductive current waveform diagram of the tradition source Z three-level inverter output；
Fig. 6 a is the capacitance voltage waveform diagram of the novel quasi- source Z three-level inverter output of the present invention；
Fig. 6 b is the capacitance voltage waveform diagram of the tradition source Z three-level inverter output；
Fig. 7 a is the line voltage waveform diagram of the novel quasi- source Z three-level inverter output of the present invention；
Fig. 7 b is the line voltage waveform diagram of the tradition source Z three-level inverter output；
Fig. 8 a is L-type filter networking electric current and its spectral characteristic figure；
Fig. 8 b is the LCL type filter networking electric current and its spectral characteristic figure of the passive damping of injection of the present invention；
Fig. 9 is the active power of the quasi- source Z three-level inverter of the present invention output, reactive power waveform diagram；
Figure 10 is the quasi- Z-source inverter a phase grid-connected voltage current waveform figure under reference power.
Specific embodiment
The present invention is on the structure & working mechanism of the source analysis conventional Z three-level inverter, by switched inductors technical application To Z source network topology, and unsymmetric structure is used, and the simplification PQ filtered based on LCL control is introduced into quasi- three level of the source Z In the cutting-in control of inverter, grid-connected inverters control is realized in conjunction with improved SVPWM.
Fig. 1 is the topological structure of the quasi- source Z three-level inverter of the present invention.Using dual power supply, 2 voltages are uin/2 DC power supply, it is uneven to avoid DC side mid-point voltage；Quasi- Z source network part is by 4 inductance (L1~L4), 2 capacitors (C1~C2) and 7 diode (D1~D7) composition, a uin/ 2 DC power supply positive outputs connect diode D1 anode and inductance L1 mono- It holds, diode D1 and inductance L3 series connection and tie point are D1 cathode, and inductance L1 is concatenated with diode D3 to be connected and connect Contact is diode D3 anode, and in parallel after two series connections, i.e., diode D3 cathode is connect with the one end inductance L3, and diode D2 is just Pole connects diode D3 anode, and diode D2 cathode connects diode D1 cathode；Diode D3 cathode, which is namely connected in parallel, a little connects two Pole pipe D7 anode, diode D7 cathode connect diode D4 anode and the one end inductance L2, and diode D4 and inductance L4 are connected in series simultaneously And tie point is D4 cathode, inductance L2 concatenates connection with diode D6 and tie point is diode D6 anode, and two are connected in series In parallel afterwards, i.e., diode D6 cathode is connect with the one end inductance L4, and diode D5 anode connects diode D6 anode, diode D5 cathode Connect diode D4 cathode；Capacitor C1 is connected in parallel on diode D1 anode and diode D7 cathode；Capacitor C2 is being connected in parallel on diode D7 just Pole and diode D6 cathode.Such L1、L3、D1~D3Composed 1st way switch Henry, L2、L4、D4~D6It is composed 2nd way switch Henry.Three diodes and an inductance are added in each inductance, in the switched inductors unit of addition Due to using unsymmetric structure, capacitor polarity (C1 and C2) is identical as electric power polarity, can reduce the stress of capacitance voltage, reduces The volume of capacitor, save the cost.Two level thoughts are expanded into three level, two level expand to three level and refer to that inverter is every Phase switching tube becomes four by two, and trigger pulse has become 12 tunnel pulses, the switch state of phase each in this way from 6 tunnel pulses There is 0,1 to become -1,0,1. and becomes three level.Switching device voltage stress is reduced, the Waveform sine of output is higher.
The quasi- source Z three-level inverter includes sequentially connected two dc power supply, quasi- Z source network and three-level inverter, inverse Become device outlet and is connected to LCL type filter.
Compared with SPWM modulation, SVPWM modulation is more easily implemented digitlization.And have voltage utilization higher, switch damage The advantages such as consumption and percent harmonic distortion are lower, and switch combination is flexible.Due to joined novel quasi- Z source network, in addition to tradition to be realized Other than three-level inverter function, it is also necessary to it is boosted by being rationally inserted into straight-through vector realization up and down, and remaining of modulation strategy Different degrees of change also has occurred in part.For example, realizing that the waveform of time state distribution has become 11 from 7 segmentations before Segmentation.As shown in Figure 2 a and 2 b.
Fig. 3 is the LCL type filter of use compared with the Bode diagram of L-type filter.LCL filter is a 3 levels system, It is by inverter side inductance, and net side inductance and capacitor form.By comparing L filter and LCL type filter Bode diagram as it can be seen that The two basic indifference in low frequency, but in high frequency, LCL fall off rate is bigger, and there are resonance points.To weaken LCL The resonance spikes of filter inject active damping Rd。
Fig. 4 is the grid-connection control system of novel quasi- Z-source inverter of the present invention.In figure, Z0It is the resistance of transmission line of electricity It is anti-, ux(x=a, b, c) is that gird-connected inverter passes through the filtered voltage of LCL, ixFor the filtered electric current of LCL, exIt is defeated for power grid Enter voltage.Quasi- Z-source inverter accesses power grid after filtering by LCL.Simplifying invariable power PQ control includes power control, current control Three parts are converted with abc-dq, specifically includes and acquires grid-connected three-phase voltage e by voltage and current acquisition modulexWith electric current ix, By phaselocked loop (Phase-Locked Loop, PLL) and abc-dq transform part, d axis and q shaft voltage e are obtaineddqAnd electric current idq；Given active and reactive reference power Pref、Qref, the reference current of d axis, q axis is calculated by power control link idref、iqref, then according to current control link, with actual current d axis, q shaft current id、iqCompare, calculates d axis, q axis The reference value u of voltagedref、uqref；Finally by dq-abc transform part, it is converted into three-phase voltage reference value uxref, as The input value of SVPWM gives straight-through duty ratio D appropriate at the same time0Modulated signal is exported to inversion into SVPWM, SVPWM Device.
Quasi- Z-source inverter injection AC network power can indicate are as follows:
In formula: line impedance of the Z between filter and AC network；For line impedance angle；φ is filter outlet Voltage is with respect to AC network side voltage phase difference；Pgrid、QgridRespectively inject active power, the reactive power of power grid.
As shown in Figure 4, grid-connected busbar voltage may be expressed as:
Formula (2) is transformed into dq coordinate system, is obtained:
In formula: ω is grid-connected route angular frequency, and R is grid-connected line resistance, and L is grid-connected line inductance.
Under dq coordinate system, quasi- Z-source inverter flows into the power of bulk power grid through LCL filter system are as follows:
In abc-dq transformation, selection d axis is identical with voltage vector direction, leads to eqEqual to zero.At this moment, PrefOnly and idPhase It closes, QrefOnly with iqIt is related.Grid power expression formula is injected to simplify are as follows:
Formula (3) is arranged, can be obtained:
In order to verify the feasibility for the grid-connection control system for proposing the quasi- source Z three-level inverter, herein in Matlab/ QZSI has been built on Simulink software and its has simplified PQ control model, its simulation waveform has been researched and analysed.It is imitative True parameter value are as follows: input direct-current voltage Uin=800V, switching frequency f=2.5kHz；Quasi- Z source network capacitor C1=C2=1000 μ F, inductance L1=L2=L3=L4=1mH, damping resistance Rd=0.8 Ω；Straight-through duty ratio D=0.1；Filter inductance L1x=L2x= 12mH, filter capacitor Cf=60 μ F；L-type filter inductance Lf=24mH.The parameter of PI controller is KP=55, KI=50；Power grid Phase voltage is 220V, frequency 50Hz；The given P of systemref60kW, Q are increased to by 20Kw in 0.1srefIt is increased to by 0Var 10kVar。
Fig. 5 a, 5b are respectively that the novel quasi- source Z three-level inverter of the present invention and the tradition source Z three-level inverter are defeated Inductive current waveform out.Due to using switched inductors technology, inductive current is about 45A when stable state, and inductive current impacts It is small.And the tradition source Z three-level inverter inrush current is very big, has reached 110A, this will cause to damage to the source Z major loop It is bad.
Fig. 6 a, 6b are respectively that the novel quasi- source Z three-level inverter of the present invention and the tradition source Z three-level inverter are defeated Capacitance voltage waveform out.Due to using unsymmetric structure, and capacitor polarity is identical as electric power polarity, greatly reduces capacitor electricity Compression.Work as uinWhen=800V, the D=0.1 of insertion, when stable state quasi- Z-source inverter ucIt is approximately equal to 230V, the inversion of traditional source Z Its u of devicecGreater than uin, it is easily destroyed capacitor, and then destroy quasi- Z source network.
Fig. 7 a, 7b are respectively that the novel quasi- source Z three-level inverter of the present invention, the tradition source Z three-level inverter are defeated Line voltage waveform out.Due to inserting straight-through duty ratio D=0.1, the sensitizing factor of quasi- Z-source inverter can achieve 1.57, And traditional its sensitizing factor of Z-source inverter only has 1.25.Quasi- Z-source inverter line voltage peak value has reached 1200V, and the tradition source Z Inverter line voltage peak value only about 950V, therefore, quasi- Z-source inverter greatly improves boost effect.
Fig. 8 a, 8b are respectively the LCL type networking electric current and its spectral characteristic figure of L-type filter, the passive damping of injection.LCL Mode filter grid-connected current total harmonic distortion factor (THD) is 3.17%, lower than the THD=4.31% of L-type filter, and LCL wave Variance of peak is lower.It can be seen that LCL-filter can more preferably reduce grid-connected THD, improve into network electric energy quality.
Fig. 9 is the active power of the quasi- source Z three-level inverter of the present invention output, reactive power waveform.Setting is imitative The true time is 0.25s, and in t=0.1s, active power reference value becomes 60kW from 20kW, and reactive power reference qref is become by 0Var At 10kVar.As seen from the figure, inverter output power quickly can follow reference power to change, and waveform is smooth, and network control System is good.
Figure 10 is a phase grid-connected voltage and current waveform under LCL filtering.As seen from the figure, before 0.1s, due to Qref= 0, grid-connected current is identical as bulk power grid voltage-phase, and power-factor cos ψ is 1 at this time.Due to accessing bulk power grid, voltage is dragged into It is synchronous.Grid-connected phase voltage peak value is 311V, and grid-connected current is approximately equal to 43A, and the P of QZSI output is equal to 20kW and PrefIt is consistent. It is grid-connected to work well.After 0.1s, since reference reactive power has become 10kVar, grid-connected current voltage has certain phase Difference, power factor is approximately equal to 0.986 at this time.
In conclusion the above is merely preferred embodiments of the present invention, being not intended to limit the scope of the present invention. All within the spirits and principles of the present invention, any modification, equivalent replacement, improvement and so on should be included in of the invention Within protection scope.

Claims (3)

1. a kind of novel quasi- source Z three-level inverter, which is characterized in that including sequentially connected two dc power supply, quasi- Z source network And three-level inverter, use 2 voltages for uin/ 2 DC power supply；Quasi- Z source network part is by 4 inductance, 2 capacitors and 7 A diode composition, a uin/ 2 DC power supply positive outputs connect diode D1 anode and the one end inductance L1, diode D1 and inductance L3 be connected in series and tie point be D1 cathode, inductance L1 concatenate with diode D3 connect and tie point for diode D3 just Pole, in parallel after two series connections, i.e., diode D3 cathode is connect with the one end inductance L3, and diode D2 anode is meeting diode D3 just Pole, diode D2 cathode connect diode D1 cathode；Diode D3 cathode, which is namely connected in parallel, a little connects diode D7 anode, two poles Pipe D7 cathode connects diode D4 anode and the one end inductance L2, and diode D4 and inductance L4 are connected in series and tie point is negative for D4 Pole, inductance L2 concatenates connection with diode D6 and tie point is diode D6 anode, in parallel after two series connections, i.e. diode D6 cathode is connect with the one end inductance L4, and diode D5 anode connects diode D6 anode, and diode D5 cathode connects diode D4 cathode； Capacitor C1 is connected in parallel on diode D1 anode and diode D7 cathode；Capacitor C2 is connected in parallel on diode D7 anode and diode D6 is negative Pole.
2. the novel quasi- source Z three-level inverter invariable power grid-connection control system according to claim 1, which is characterized in that institute It states and accesses power grid after quasi- Z-source inverter is filtered by LCL, invariable power grid-connection control system includes power control link, electric current control Three parts of link processed and abc-dq transform part, grid-connected three-phase voltage e is acquired by voltage and current acquisition modulexAnd electric current ix, x=a, b, c, three-phase voltage exRoute angular frequency, e are obtained by phaselocked loopx、ixPass through abc-dq transform part with ω, Obtain d axis and q shaft voltage edqWith electric current idqInput power controlling unit；Given active and reactive reference power Pref、Qref, lead to Over power control link calculates the reference current i of d axis, q axisdref、iqref, then idref、iqrefInto current control link, With actual current d axis, q shaft current id、iqCompare, calculates the reference value u of d axis, q shaft voltagedref、uqref；Finally by dq- Abc transform part is converted into three-phase voltage reference value uxref, as the input value of SVPWM, give at the same time appropriate straight-through Duty ratio D0Modulated signal is exported to inverter into SVPWM, SVPWM.
3. the novel quasi- source Z three-level inverter invariable power grid-connection control system according to claim 2, which is characterized in that institute Injection grid power expression formula in power control link is stated to simplify are as follows:
Quasi- Z-source inverter shaft voltage u after abc-dq is converted by the filtered voltage of LCLdAnd uqExpression formula are as follows:
Wherein ω is grid-connected route angular frequency, and R is grid-connected line resistance, and L is grid-connected line inductance.
CN201811590221.3A 2018-12-25 2018-12-25 The novel quasi- source Z three-level inverter and its invariable power grid-connection control system Pending CN109687746A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811590221.3A CN109687746A (en) 2018-12-25 2018-12-25 The novel quasi- source Z three-level inverter and its invariable power grid-connection control system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811590221.3A CN109687746A (en) 2018-12-25 2018-12-25 The novel quasi- source Z three-level inverter and its invariable power grid-connection control system

Publications (1)

Publication Number Publication Date
CN109687746A true CN109687746A (en) 2019-04-26

Family

ID=66189269

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811590221.3A Pending CN109687746A (en) 2018-12-25 2018-12-25 The novel quasi- source Z three-level inverter and its invariable power grid-connection control system

Country Status (1)

Country Link
CN (1) CN109687746A (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106786738A (en) * 2016-12-23 2017-05-31 上海电力学院 Z-source inverter grid-connected control method based on SVPWM and PI type Fuzzy
CN108023365A (en) * 2018-01-08 2018-05-11 湖南工业大学 A kind of high-speed engine grid-connected system and its control method based on quasi- Z-source inverter
JP2018088750A (en) * 2016-11-28 2018-06-07 東洋電機製造株式会社 Power conversion device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018088750A (en) * 2016-11-28 2018-06-07 東洋電機製造株式会社 Power conversion device
CN106786738A (en) * 2016-12-23 2017-05-31 上海电力学院 Z-source inverter grid-connected control method based on SVPWM and PI type Fuzzy
CN108023365A (en) * 2018-01-08 2018-05-11 湖南工业大学 A kind of high-speed engine grid-connected system and its control method based on quasi- Z-source inverter

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
余德清: ""z源三电平逆变器及其并网控制方法研究"", 《中国优秀硕士学位论文全文数据库工程科技II辑》 *
苏宏升 等: ""多种z源逆变器的性能对比与应用背景分析"", 《控制工程》 *

Similar Documents

Publication Publication Date Title
CN107528491B (en) A kind of cascaded H-bridges multi-level converter and its control method
CN108574403B (en) Non-isolation type photovoltaic DC-to-AC converter common mode resonance loop current and drain current suppressing method
Ahmad et al. Comparative analysis of single phase transformerless inverter topologies for grid connected PV system
Cha et al. Comparative analysis of low-pass output filter for single-phase grid-connected Photovoltaic inverter
CN106981976B (en) The method of T-type three-level three-phase inverter inhibition middle line common mode current
CN108880209B (en) Active damping control method of active third harmonic injection matrix converter
CN107276091B (en) NPC type three-level three-phase four-wire system SAPF nonlinear passive control method
Mehta et al. Power quality improvement through grid integration of renewable energy sources
Turksoy et al. A novel adaptive switching method to reduce DC-Link capacitor ripple in PV based grid-connected inverter
CN109245156B (en) A kind of gird-connected inverter
CN106505898A (en) Z sources NPC three-level inverter invariable power grid-connection control systems based on SVPWM
CN106208134B (en) Grid-connected topology and Poewr control method based on three-phase CLC immittance converter
CN107612398B (en) Passive control system and method for five-level NPC inverter
CN109687746A (en) The novel quasi- source Z three-level inverter and its invariable power grid-connection control system
Vipin et al. Utility scale interface for renewables and storage using a power electronic transformer with back-to-back mmcs: A novel control scheme
Karaman et al. Performing reactive power compensation of three-phase induction motor by using parallel active power filter
Xu et al. A low-voltage ride-through control strategy for two-stage T-type three-level photovoltaic inverters limiting DC-link overvoltage and grid-side overcurrent
CN112152488A (en) Three-phase three-level Vienna rectifier control system and control method
Sun et al. Three single-phase control of NPC three-level photovoltaic grid-connected inverter based on Quasi-PR control
Jabbar et al. Voltage balancing in DC link capacitor for seven level cascaded multilevel inverter
CHENNAI Simple control method for unified power quality based on five-level inverter topologies operating under all voltage disturbances
Jokipii et al. Dynamic characteristics of three-phase Z-source-based photovoltaic inverter with asymmetric impedance network
Jia et al. A New Control Strategy Based on Capacitor Current Feedback Source Damping for LCL Three-Phase Public Electric Network Inverter
Ren et al. Grid current harmonic suppression for motor drive with reduced DC-link capacitance in weak grid
Zhong et al. Control strategy of three-phase T-type three-level converter with reactive power compensation function

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
WD01 Invention patent application deemed withdrawn after publication
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20190426