CN204707054U - A kind of soft switching inverter being applicable to photovoltaic generation - Google Patents

A kind of soft switching inverter being applicable to photovoltaic generation Download PDF

Info

Publication number
CN204707054U
CN204707054U CN201520351575.8U CN201520351575U CN204707054U CN 204707054 U CN204707054 U CN 204707054U CN 201520351575 U CN201520351575 U CN 201520351575U CN 204707054 U CN204707054 U CN 204707054U
Authority
CN
China
Prior art keywords
boost
switching device
diode
photovoltaic array
emitter
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
Application number
CN201520351575.8U
Other languages
Chinese (zh)
Inventor
张庆海
李洪博
刘安华
王李
王新涛
蔡军
孔鹏
鲍景宽
李豹
董铁孝
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.)
Liaocheng Power Supply Co of State Grid Shandong Electric Power Co Ltd
Original Assignee
Liaocheng Power Supply Co of State Grid Shandong Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Liaocheng Power Supply Co of State Grid Shandong Electric Power Co Ltd filed Critical Liaocheng Power Supply Co of State Grid Shandong Electric Power Co Ltd
Priority to CN201520351575.8U priority Critical patent/CN204707054U/en
Application granted granted Critical
Publication of CN204707054U publication Critical patent/CN204707054U/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/56—Power conversion systems, e.g. maximum power point trackers

Landscapes

  • Inverter Devices (AREA)

Abstract

The utility model discloses a kind of soft switching inverter being applicable to photovoltaic generation, comprise Boost circuit, DC side storage capacitor, auxiliary resonance circuit, PWM inverter bridge, photovoltaic array, Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, three-phase resistance inductive load connect in turn, photovoltaic array export direct current energy be for conversion into AC energy, be three-phase resistance sense load supplying; Auxiliary resonance circuit contains coupled resonance inductance, and structure is relatively simple, and passive additional device is less, and derided capacitors of not connecting in inverter structure, so do not have the variation issue of neutral point potential, is conducive to reducing hardware cost.When making photovoltaic array output voltage drop to zero by the resonance of auxiliary circuit, the main switching device of PWM inverter bridge can complete zero voltage switch, auxiliary switch device also can complete Sofe Switch in the course of work of auxiliary resonance circuit simultaneously, and photovoltaic array export the no-voltage duration can unrestricted choice, have nothing to do with load current and resonant parameter.

Description

A kind of soft switching inverter being applicable to photovoltaic generation
Technical field
The utility model relates to a kind of soft switching inverter being applicable to photovoltaic generation, belongs to distributed power generation and intelligent grid field.
Background technology
The global energy important channel with problem of environmental pollution in short supply is alleviated in the utilization of solar energy, and photovoltaic generation is exactly one of focus of Recent study.The load supplying higher to direct voltage, battery tension is generally lower, can not meet its power demands.Adopt at present ripe electric electronic current change technology to convert solar energy to electric energy, and then realize voltage transformation and power controls.
Soft switch technique, in the successful Application in DC converter field, makes people show keen interest to the application of soft switch technique in inverter.All solution has been invested Sofe Switch when relating to the problems that traditional hard switching inverter brings, as low switching frequency, high switching loss, the instantaneous serious current/voltage spike of switch, to electromagnetic interference and the audio-frequency noise of environment.In order to obtain efficient, high-performance, high power density inverter, the concern that parallel resonance DC link joint soft switching inverter is simple with its structure, control is conveniently subject to researcher is the main flow of current soft switching inverter topology research and development.
Summary of the invention
The technical problems to be solved in the utility model is: for the deficiencies in the prior art, provides a kind of soft switching inverter being applicable to photovoltaic generation, and its auxiliary resonance circuit contains coupled resonance inductance, and structure is relatively simple, is conducive to reducing hardware cost.When making photovoltaic array output voltage drop to zero by the resonance of auxiliary resonance circuit, the main switching device of inverter bridge can complete zero voltage switch, auxiliary switch device also can complete Sofe Switch in the course of work of auxiliary resonance circuit simultaneously, and photovoltaic array export the no-voltage duration can unrestricted choice, have nothing to do with load current and resonant parameter.
The technical solution of the utility model is: a kind of soft switching inverter being applicable to photovoltaic generation, comprises Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge; Photovoltaic array, Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, three-phase resistance inductive load connect in turn, photovoltaic array export direct current energy be for conversion into AC energy, be three-phase resistance sense load supplying; Boost circuit comprises photovoltaic side storage capacitor C 0, Boost boost inductance L 0, Boost circuit switching device S 0, Boost circuit diode VD 0; Auxiliary resonance circuit comprises coupled resonance inductance L r1, L r2, auxiliary switch device S a1, S a2, and S a1anti-paralleled diode VD a1with booster diode VD a2; Photovoltaic array and photovoltaic side storage capacitor C 0be connected in parallel, photovoltaic array output cathode and Boost boost inductance L 0be connected, Boost boost inductance L 0the other end and Boost circuit switching device S 0collector electrode, Boost circuit diode VD 0anode be connected, Boost circuit diode VD 0negative electrode and DC side storage capacitor C 1one end, diode VD a1negative electrode, switching device S a1collector electrode be connected, DC side storage capacitor C 1the other end and Boost circuit switching device S 0emitter, switching device S a2emitter, diode VD a2anode, photovoltaic array output negative pole be connected; Switching device S a1emitter and diode VD a1anode, coupled resonance inductance L r1, L r2a respective different name end be connected, coupled resonance inductance L r1the other end and switching device S a2collector electrode be connected, coupled resonance inductance L r2the other end and diode VD a2negative electrode be connected; PWM inverter bridge adopts three-phase full-bridge inverter, comprises six switching device S 1~ S 6and their respective anti-paralleled diodes and parallel connection buffer electric capacity; Switching device S 1, S 3, S 5collector electrode be connected, as the input anode of PWM inverter bridge, and with auxiliary resonance circuit breaker in middle device S a1emitter be connected; Switching device S 2, S 4, S 6emitter be connected, as the input negative terminal of PWM inverter bridge, and be connected with photovoltaic array output negative pole; S 1emitter and S 2collector electrode be connected, S 3emitter and S 4collector electrode be connected, S 5emitter and S 6collector electrode be connected, by S 2, S 4, S 6collector electrode draw a, b, c tri-outputs of PWM inverter bridge respectively; A, b, c tri-outputs of PWM inverter bridge are connected with a phase of three-phase resistance inductive load, b phase, c respectively.
The beneficial effects of the utility model are: derided capacitors of 1, not connecting in inverter structure, without the variation issue of neutral point potential; 2, auxiliary resonance circuit structure is relatively simple, only has 2 auxiliary switches, 2 coupled resonance inductance and 1 booster diode; 3, the photovoltaic array output no-voltage duration does not rely on load current and resonant parameter, and its no-voltage duration can be selected arbitrarily as required.
Accompanying drawing explanation
Fig. 1 is the utility model structural representation.
Fig. 2 is the utility model equivalent circuit diagram; i lr1, i lr2be respectively and flow through L r1, L r2electric current, u crfor electric capacity C rthe voltage at two ends.
Fig. 3 is feature work oscillogram of the present utility model.
Embodiment
Below in conjunction with Figure of description, the technical solution of the utility model is further elaborated, but is not limited thereto.
As shown in Figure 1, a kind of soft switching inverter structural representation being applicable to photovoltaic generation, comprises Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, photovoltaic array, Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, three-phase resistance inductive load connect in turn, photovoltaic array export direct current energy be for conversion into AC energy, be three-phase resistance sense load supplying.
Boost circuit comprises photovoltaic side storage capacitor C 0, Boost boost inductance L 0, Boost circuit switching device S 0, Boost circuit diode VD 0; Auxiliary resonance circuit comprises coupled resonance inductance L r1, L r2, auxiliary switch device S a1, S a2, and S a1anti-paralleled diode VD a1with booster diode VD a2; Photovoltaic array and photovoltaic side storage capacitor C 0be connected in parallel, photovoltaic array output cathode and Boost boost inductance L 0be connected, Boost boost inductance L 0the other end and Boost circuit switching device S 0collector electrode, Boost circuit diode VD 0anode be connected, Boost circuit diode VD 0negative electrode and DC side storage capacitor C 1one end, diode VD a1negative electrode, switching device S a1collector electrode be connected, DC side storage capacitor C 1the other end and Boost circuit switching device S 0emitter, switching device S a2emitter, diode VD a2anode, photovoltaic array output negative pole be connected; Switching device S a1emitter and diode VD a1anode, coupled resonance inductance L r1, L r2a respective different name end be connected, coupled resonance inductance L r1the other end and switching device S a2collector electrode be connected, coupled resonance inductance L r2the other end and diode VD a2negative electrode be connected; PWM inverter bridge adopts three-phase full-bridge inverter, comprises six switching device S 1~ S 6and their respective anti-paralleled diodes and parallel connection buffer electric capacity; Switching device S 1, S 3, S 5collector electrode be connected, as the input anode of PWM inverter bridge, and with auxiliary resonance circuit breaker in middle device S a1emitter be connected; Switching device S 2, S 4, S 6emitter be connected, as the input negative terminal of PWM inverter bridge, and be connected with photovoltaic array output negative pole; S 1emitter and S 2collector electrode be connected, S 3emitter and S 4collector electrode be connected, S 5emitter and S 6collector electrode be connected, by S 2, S 4, S 6collector electrode draw a, b, c tri-outputs of PWM inverter bridge respectively; A, b, c tri-outputs of PWM inverter bridge are connected with a phase of three-phase resistance inductive load, b phase, c respectively.
Boost circuit realizes maximal power tracing, and auxiliary resonance circuit provides zero voltage switch condition for PWM converter bridge switching parts device, and PWM inverter bridge realizes DC/AC conversion.Switching device shutoff or open-minded during photovoltaic array exports no-voltage groove of PWM inverter bridge, the overlap of no-voltage and electric current during power device switch, thus reduce switching loss.
To simplify the analysis, following hypothesis is done: 1, device is ideal operation state; 2, photovoltaic array, Boost circuit, DC side storage capacitor C 1be equivalent to a direct voltage source E; 3, load inductance is much larger than resonant inductance, and the load current of converter bridge switching parts status transition moment can think constant-current source I 0, load current direction remains unchanged, and its numerical value depends on the instantaneous value of each phase current and the on off state of inverter bridge 6 switching devices; 4,6 main switching devices of inverter bridge are equivalent to S inv, the antiparallel fly-wheel diode of main switching device is equivalent to VD inv; 5,6 buffer capacitors of inverter bridge are equivalent to C r, get C r=3C s, C sfor the size of each buffer capacitor; This is because when the switching device of the upper and lower any one party of each brachium pontis of inverter bridge is connected, all make the electric capacity C in parallel with it sshort circuit, electric capacity during normal work on 3 brachium pontis is equivalent to 3 Capacitance parallel connections.
On above-mentioned 5 hypothesis bases, can obtain equivalent circuit diagram of the present utility model shown in Fig. 2, the current/voltage of each several part is just all with the direction shown in Fig. 2.
The utility model can be divided into 7 mode of operations in a switch periods, and as shown in Figure 3, transverse axis is time shaft to feature work waveform, and the longitudinal axis is the value of waveform corresponding to time.Respectively each mode of operation is introduced below in conjunction with Fig. 2 and Fig. 3.
Mode of operation 1(t ~ t 0): initial condition, power supply is by auxiliary switch device S a1to Load transportation electric energy.
Mode of operation 2(t 0~ t 1): at t 0in the moment, open auxiliary switch device S a2, in coupled resonance inductance L r1effect under, reduce and flow through auxiliary switch device S a2the climbing of electric current, so S a2achieve zero current turning-on.S a2after opening, coupled resonance inductance L r1the magnitude of voltage born is E, L r1charged, current i lr1linear increase, at t 1in the moment, mode of operation 2 terminates, now i lr1linearly increase to current value I b1.
Mode of operation 3(t 1~ t 2): at t 1in the moment, turn off auxiliary switch device S a1, at electric capacity C reffect under, reduce S a1the climbing of shutdown moment terminal voltage, so S a1achieve zero voltage turn-off.S a1after shutoff, L r1and C rstart resonance, L r1charged, C relectric discharge.I lr1increase gradually, u crreduce gradually.At t 2in the moment, work as u crbe reduced to zero, i lr1increase to maximum I 1time, mode of operation 3 terminates.In this pattern, C rexcept to L r1beyond the branch road electric discharge of place, also simultaneously to load discharge, constant to maintain load current.
Mode of operation 4(t 2~ t 3): establish N 1and N 2be respectively coupling inductance L r1and L r2the number of turn, turn ratio n=N 2/ N 1, U sa2, onand U vDa2, onbe respectively S a2and VD a2on-state voltage drop.At t 2in the moment, work as u crwhen being reduced to zero, diode VD a2conducting.Flow through L r1current i lr1from I 1be mutated into I lr1, flow through L r2current i lr2i is mutated into from zero lr2, then i lr1and i lr2remain constant I respectively lr1and I lr2.If consider on-state voltage drop U sa2, onand U vDa2, on, so in this pattern, u cr=(nU sa2, on-U vDa2, on)/(n+1).Because turn ratio n > 1, so u cr> 0, equivalent diode VD invnot conducting, load current I 0pass through L r2and VD a2the branch road afterflow at place.
Mode of operation 5(t 3~ t 4): at t 3in the moment, turn off auxiliary switch device S a2, at electric capacity C reffect under, reduce S a2the climbing of shutdown moment terminal voltage, so S a2achieve zero voltage turn-off.At S a2shutdown moment, flows through L r2current i lr2from I lr2be mutated into I 1/ n.S a2after shutoff, L r2and C rstart resonance, L r2electric discharge, C rcharged, i lr2reduce gradually, u crincrease gradually.L r2also simultaneously to load discharge, constant to maintain load current.At t 4in the moment, work as i lr2be reduced to I 2, u crwhen increasing to E, mode of operation 5 terminates.
Mode of operation 6(t 4~ t 5): at t 4moment, S a1anti-paralleled diode VD a1start conducting, now open auxiliary switch device S a1, S a1achieve no-voltage open-minded.VD a1after conducting, L r2the magnitude of voltage born is E, flows through L r2current i lr2from I 2linear reduction.At t 5in the moment, work as i lr2linearly be reduced to load current value I 0time, diode VD a1cut-off, mode of operation 6 terminates.
Mode of operation 7(t 5~ t 6): at t 5moment, S a1start conducting, flow through L r2current i lr2from I 0continue linear reduction.At t 6in the moment, work as i lr2when being linearly reduced to zero, mode of operation 7 terminates.

Claims (1)

1. be applicable to a soft switching inverter for photovoltaic generation, it is characterized in that, comprise Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, photovoltaic array, Boost circuit, DC side storage capacitor C 1, auxiliary resonance circuit, PWM inverter bridge, three-phase resistance inductive load connect in turn, photovoltaic array export direct current energy be for conversion into AC energy, be three-phase resistance sense load supplying; Boost circuit comprises photovoltaic side storage capacitor C 0, Boost boost inductance L 0, Boost circuit switching device S 0, Boost circuit diode VD 0; Auxiliary resonance circuit comprises coupled resonance inductance L r1, L r2, auxiliary switch device S a1, S a2, and S a1anti-paralleled diode VD a1with booster diode VD a2; Photovoltaic array and photovoltaic side storage capacitor C 0be connected in parallel, photovoltaic array output cathode and Boost boost inductance L 0be connected, Boost boost inductance L 0the other end and Boost circuit switching device S 0collector electrode, Boost circuit diode VD 0anode be connected, Boost circuit diode VD 0negative electrode and DC side storage capacitor C 1one end, diode VD a1negative electrode, switching device S a1collector electrode be connected, DC side storage capacitor C 1the other end and Boost circuit switching device S 0emitter, switching device S a2emitter, diode VD a2anode, photovoltaic array output negative pole be connected; Switching device S a1emitter and diode VD a1anode, coupled resonance inductance L r1, L r2a respective different name end be connected, coupled resonance inductance L r1the other end and switching device S a2collector electrode be connected, coupled resonance inductance L r2the other end and diode VD a2negative electrode be connected; PWM inverter bridge adopts three-phase full-bridge inverter, comprises six switching device S 1~ S 6and their respective anti-paralleled diodes and parallel connection buffer electric capacity; Switching device S 1, S 3, S 5collector electrode be connected, as the input anode of PWM inverter bridge, and with auxiliary resonance circuit breaker in middle device S a1emitter be connected; Switching device S 2, S 4, S 6emitter be connected, as the input negative terminal of PWM inverter bridge, and be connected with photovoltaic array output negative pole; S 1emitter and S 2collector electrode be connected, S 3emitter and S 4collector electrode be connected, S 5emitter and S 6collector electrode be connected, by S 2, S 4, S 6collector electrode draw a, b, c tri-outputs of PWM inverter bridge respectively; A, b, c tri-outputs of PWM inverter bridge are connected with a phase of three-phase resistance inductive load, b phase, c respectively.
CN201520351575.8U 2015-05-28 2015-05-28 A kind of soft switching inverter being applicable to photovoltaic generation Expired - Fee Related CN204707054U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201520351575.8U CN204707054U (en) 2015-05-28 2015-05-28 A kind of soft switching inverter being applicable to photovoltaic generation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201520351575.8U CN204707054U (en) 2015-05-28 2015-05-28 A kind of soft switching inverter being applicable to photovoltaic generation

Publications (1)

Publication Number Publication Date
CN204707054U true CN204707054U (en) 2015-10-14

Family

ID=54286646

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201520351575.8U Expired - Fee Related CN204707054U (en) 2015-05-28 2015-05-28 A kind of soft switching inverter being applicable to photovoltaic generation

Country Status (1)

Country Link
CN (1) CN204707054U (en)

Similar Documents

Publication Publication Date Title
CN101980437B (en) Five-level grid-connected inverter
CN203590031U (en) DC-DC converter realizing high-efficiency high-gain low-voltage current stress
CN103701356B (en) A kind of two auxiliary resonance polar form three phase soft switch inverter
CN105743344A (en) Isolated three-level bidirectional DC-DC converter with coupling inductor
CN102005962A (en) Buck-boost grid-connected inverter and control method thereof
CN204442176U (en) A kind of switched inductors type accurate Z source DC-DC converter circuit
CN103219912B (en) Control method suitable for universal input voltage buck-boost grid-connected inverter
CN203883673U (en) Improved Z-source boost DC-DC converter
CN205377786U (en) Two pressure reducing type photovoltaic power generation system
CN204928737U (en) Photovoltaic power generation device based on two buck dc -to -ac converters
CN204948016U (en) A kind of photovoltaic power generation apparatus adopting zero voltage switch auxiliary resonance
CN103312153A (en) Parallel multi input coupled inductor buck and boost converter
CN104811075B (en) A kind of control method of combined converter
CN204947919U (en) A kind of parallel resonance no-voltage photovoltaic power generation apparatus
CN204696954U (en) A kind of three-phase resonant pole photovoltaic DC-to-AC converter
CN105553271A (en) Control method of three-phase DC converter
CN104300780B (en) Large power non-isolation DC/DC soft switching circuit
CN203590033U (en) High gain DC/DC converter applied in photovoltaic inverter MPPT link
CN205754197U (en) Photovoltaic generating system with low energy consumption auxiliary circuit
CN204696953U (en) A kind of Z-source inverter being applicable to photovoltaic generation
CN204442168U (en) A kind of based on without bridge CUK isolated form Three Phase Power Factor Correction Converter
CN204928612U (en) Photovoltaic power generation device with auxiliary resonant circuit
CN103633835B (en) The DC-DC converter of High-efficiency high-gain low-voltage current stress
CN204696955U (en) A kind of photovoltaic DC-to-AC converter adopting transformer auxiliary resonance
CN204707054U (en) A kind of soft switching inverter being applicable to photovoltaic generation

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: 20151014

Termination date: 20160528