CN204179938U - The synchronous grid-connected system of a kind of inverter - Google Patents
The synchronous grid-connected system of a kind of inverter Download PDFInfo
- Publication number
- CN204179938U CN204179938U CN201420662713.XU CN201420662713U CN204179938U CN 204179938 U CN204179938 U CN 204179938U CN 201420662713 U CN201420662713 U CN 201420662713U CN 204179938 U CN204179938 U CN 204179938U
- Authority
- CN
- China
- Prior art keywords
- grid
- inverter
- circuit
- bus capacitor
- circuit breaker
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The utility model relates to the synchronous grid-connected system of a kind of inverter, comprise the DC side switch connected successively, direct current EMC filter, bus capacitor assembly, power model, inductance, output filter assembly, exchange EMC filter, grid-connected contactor, softly open circuit and AC circuit breaker, the soft circuit that opens is by pre-charge contactor, rectifier bridge and series resistance are formed, softly open the bus capacitor assembly that circuit on one side is connected to DC side, one end connects AC circuit breaker, by constantly detecting bus capacitor component voltage and phase value, generate electricity by way of merging two or more grid systems when this value is identical with line voltage and phase value, rush of current when reducing grid-connected, the useful life of the big current grid-connected switch that significant prolongation inverter internal device is especially expensive.
Description
Technical field
The utility model relates to inverter technology field, particularly relates to the synchronous grid-connected system of the inverter with AC soft start function.
Background technology
The direct current energy that photovoltaic module produces is all be transformed to the AC energy of mating with electrical network by photovoltaic combining inverter usually, then is conveyed into electrical network.Inverter is generally made up of DC boosting loop and inversion circuit, is a kind of power adjusting device be made up of semiconductor device, is mainly used in direct current conversion and exchanges.In the application of high power UPS, wind-powered electricity generation, photovoltaic DC-to-AC converter and energy storage inverter, employ a large amount of dc-link capacitances and exchange output filter capacitor, grid-connected instantaneously to the rush of current of grid-connected switch, electrical network and electric capacity in order to reduce, the general method adopting series resistance current limliting soft start.
At present, the soft mode opened has that DC side is soft to open with AC soft two kinds, Chinese patent CN102545678A discloses a kind of inverter and opens machine method, have employed DC side soft start, comprise the DC side switch of cascade successively, bus capacitor assembly, power model, output filter assembly, grid-connected contactor, and AC circuit breaker, DC side switch is connected to DC side input, described AC circuit breaker is connected to electrical network, the input and output side of soft starting device inputs with DC side respectively and described power model is connected, this kind of method needs to set up special increasing apparatus in DC side, system construction cost is higher.
Chinese patent CN103887824A discloses a kind of control system and control method of Voltage loop ripple compensation of photovoltaic combining inverter, have employed that AC is soft to be opened, but due to just simply by setting up certain voltage on bus capacitor, in voltage-phase amplitude, larger error is had with the alternating voltage of grid side, so and in network process, larger grid-connected impact still can be caused.
Chinese patent CN103248067A discloses a kind of low voltage ride through control method of photovoltaic combining inverter, it is characterized in that, comprises the following steps: step S1: judge whether line voltage value is less than the low voltage value upper limit, no, then control inverter normally runs, and is, then enter step S2; Step S2: judge whether line voltage value is not more than low voltage value lower limit; That then control inverter quits work; No, then the active current value that control inverter exports equals target active current value, and the reactive current value exported equals target reactive current value; Wherein, the total current that described inverter exports is less than preset value with the difference that compares of the electric current of output grid-connected under normality.
Utility model content
The method that system of the present utility model adopts AC to start, while busbar voltage is set up, by the reverse inversion modulation of inverter bridge leg, voltage conversion circuit is formed by power model and inductance, direct voltage is made to carry out discharge and recharge to inductance, the other end of such inductance just can obtain alternating voltage, and finally set up with line voltage with the synchronous alternating voltage of amplitude on ac capacitor, and then carry out dropping into grid-connected switch and carry out grid-connected, overcome existing simple heavy current impact problem of the mode of busbar charging being carried out to the grid-connected switch of switching, the useful life of the big current grid-connected switching device that significant prolongation inverter internal device is especially expensive.
In order to achieve the above object, the technical scheme that the utility model adopts is:
The synchronous grid-connected system of a kind of inverter, is characterized in that, comprising:
The DC side switch connected successively, direct current EMC filter, bus capacitor assembly, power model, inductance, output filter assembly, exchange EMC filter, grid-connected contactor, softly open circuit and AC circuit breaker, the soft circuit that opens is made up of pre-charge contactor, rectifier bridge and series resistance, softly open the bus capacitor assembly that circuit on one side is connected to DC side, one end connects AC circuit breaker.
Preferably, output filter assembly adopts electric capacity or capacitance component.
Preferably, power model adopts power field effect pipe (MOSFET), insulated gate bipolar transistor (IGBT) or turn-off thyristor (GTO).
The full-wave rectification bridge that rectifier bridge is preferably made up of 4 rectifier diodes.
Utilize the synchronous combination method of the inverter of system of the present utility model, there are following steps:
A) closed AC circuit breaker, now system obtains electric, allows inverter to open machine;
B) closed pre-charge contactor, the soft circuit that opens is started working, and grid power becomes direct current by rectifier bridge, and is the charging of bus capacitor assembly;
C) while closed pre-charge contactor, controller starts timing, if the timing cycle time of setting arrives, then controller judges whether described busbar voltage is more than or equal to the busbar voltage threshold value of back-modulation needs, if NO, then continues soft opening, continue to utilize grid power for the charging of bus capacitor assembly, if yes, then the voltage D modulated as required, Q axle component carries out open loop respectively and sends out ripple;
D) constantly gather the voltage magnitude on output filter assembly and phase signal, judge whether to keep with amplitude same-phase with mains voltage signal, if so, then close grid-connected contactor, generate electricity by way of merging two or more grid systems thus; If not, then grid-connected synchronization failure fault is reported;
E), after the whole soft time of opening arrives, whether the voltage magnitude phase signal judged on described filter assembly by controller reaches the phase locked threshold value with grid voltage amplitude; If not, then synchronous grid-connected failed fault is reported; If so, then synchronously softly end is opened;
F) one soft open the time period after, normally start not yet, after the system failure resets, then restart one new softly open the time period, repeat step c) to e).
The method that system of the present utility model adopts AC to start, simultaneously while busbar voltage is set up, by the reverse inversion modulation of inverter bridge leg, ac capacitor is set up with line voltage with the synchronous alternating voltage of amplitude, and then carry out dropping into grid-connected switch and carry out grid-connected method, overcome and existingly simply the heavy current impact inverter internal device of the grid-connected switch of switching and grid-connected switch problem are carried out to the mode of busbar charging.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of the synchronous grid-connected system of inverter according to employing inverter ac side of the present utility model soft starting device;
Fig. 2 is the flow chart of the inverter ac side soft-start method illustrated according to the utility model system.
Embodiment
Below in conjunction with accompanying drawing of the present utility model, be clearly and completely described synchronous grid-connected system of the present utility model, obviously, described embodiment, only for explaining the utility model, is not intended to limit scope of the present utility model.
Execution mode of the present utility model is described in detail below in conjunction with accompanying drawing.
Fig. 1 is the schematic diagram of the synchronous grid-connected system of inverter of employing inverter ac side of the present utility model soft starting device.As shown in Figure 1, inverter of the present utility model is such as photovoltaic combining inverter, mainly comprise connect successively DC side switch 13, direct current EMC filter 9, bus capacitor assembly 4, power model 3, inductance 8, output filter assembly 1, exchange EMC filter 10, grid-connected contactor 5, softly open circuit 2 and AC circuit breaker 7.The soft circuit 2 that opens is made up of pre-charge contactor 6, rectifier bridge 11 and series resistance 12, softly opens the bus capacitor assembly 4 that circuit 2 one end is connected to DC side, and one end connects AC circuit breaker 7.DC side switch 13 and AC circuit breaker 7 are respectively equipped with insurance fuse (being labeled as FUSE in accompanying drawing 1).Output filter assembly 1 can adopt electric capacity or capacitance component, power model 3 can adopt power field effect pipe (MOSFET), insulated gate bipolar transistor (IGBT), turn-off thyristor (GTO) etc., and rectifier bridge is the full-wave rectification bridge be made up of 4 rectifier diodes.
Described inverter also comprises controller, and it is connected in circuit, and controls the machine that the opens process of described inverter.
The following describes the course of work according to the synchronous grid-connected system of inverter of the present utility model.
Fig. 2 is the flow chart of the inverter ac side soft-start method utilizing the synchronous grid-connected system of the utility model inverter.
As shown in Figure 2, a) closed AC circuit breaker 7, now system obtains electric, allows inverter to open machine;
B) closed pre-charge contactor 6, the soft circuit 2 that opens is started working, and grid power becomes direct current by rectifier bridge, and charges for bus capacitor assembly 4;
C) while closed pre-charge contactor 6, controller starts timing, if the timing cycle time of setting arrives, then controller judges whether described busbar voltage is more than or equal to the busbar voltage threshold value of back-modulation needs, if NO, then continues soft opening, continue to utilize grid power to charge for bus capacitor assembly 4, if yes, then the voltage D modulated as required, Q axle component carries out open loop respectively and sends out ripple;
D) constantly gather the voltage magnitude on output filter assembly 1 and phase signal, judge whether to keep with amplitude same-phase with mains voltage signal, if so, then close grid-connected contactor 5, generate electricity by way of merging two or more grid systems thus.If not, then grid-connected synchronization failure fault is reported;
E), after the whole soft time of opening arrives, whether the voltage magnitude phase signal judged on described filter assembly by controller reaches the phase locked threshold value with grid voltage amplitude.If not, then synchronous grid-connected failed fault is reported; If so, then synchronously softly end is opened;
F) one soft open the time period after, normally start not yet, after the system failure resets, then restart one and new softly open the time period, repeat step c) to e).
More than illustrate the utility model just illustrative; and it is nonrestrictive; those of ordinary skill in the art understand; when not departing from the spirit and scope that following claims limit; many amendments, change or equivalence can be made, but all will fall in protection range of the present utility model.
Claims (4)
1. the synchronous grid-connected system of inverter, is characterized in that, comprising:
The DC side switch connected successively, direct current EMC filter, bus capacitor assembly, power model, inductance, output filter assembly, exchange EMC filter, grid-connected contactor, softly open circuit and AC circuit breaker, the soft circuit that opens is made up of pre-charge contactor, rectifier bridge and series resistance, softly open the bus capacitor assembly that circuit on one side is connected to DC side, one end connects AC circuit breaker.
2. the synchronous grid-connected system of inverter according to claim 1, is characterized in that, output filter assembly adopts electric capacity or capacitance component.
3. the synchronous grid-connected system of inverter according to claim 1, is characterized in that, power model adopts power field effect pipe, insulated gate bipolar transistor or turn-off thyristor.
4. the synchronous grid-connected system of inverter according to claim 1, is characterized in that, rectifier bridge is the full-wave rectification bridge be made up of 4 rectifier diodes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420662713.XU CN204179938U (en) | 2014-11-07 | 2014-11-07 | The synchronous grid-connected system of a kind of inverter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420662713.XU CN204179938U (en) | 2014-11-07 | 2014-11-07 | The synchronous grid-connected system of a kind of inverter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204179938U true CN204179938U (en) | 2015-02-25 |
Family
ID=52568712
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420662713.XU Active CN204179938U (en) | 2014-11-07 | 2014-11-07 | The synchronous grid-connected system of a kind of inverter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204179938U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104300777A (en) * | 2014-11-07 | 2015-01-21 | 深圳市永联科技有限公司 | Inverter synchronous grid connection method |
| CN108199575A (en) * | 2018-02-11 | 2018-06-22 | 天津瑞能电气有限公司 | A kind of high-power converter soft starting circuit |
| US20190305708A1 (en) * | 2018-04-03 | 2019-10-03 | Regal Beloit America, Inc. | Drive circuit for electric motors |
-
2014
- 2014-11-07 CN CN201420662713.XU patent/CN204179938U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104300777A (en) * | 2014-11-07 | 2015-01-21 | 深圳市永联科技有限公司 | Inverter synchronous grid connection method |
| CN104300777B (en) * | 2014-11-07 | 2017-06-23 | 深圳市永联科技股份有限公司 | A kind of inverter synchronization combination method |
| CN108199575A (en) * | 2018-02-11 | 2018-06-22 | 天津瑞能电气有限公司 | A kind of high-power converter soft starting circuit |
| US20190305708A1 (en) * | 2018-04-03 | 2019-10-03 | Regal Beloit America, Inc. | Drive circuit for electric motors |
| US10630219B2 (en) * | 2018-04-03 | 2020-04-21 | Regal Beloit America, Inc. | Drive circuit for electric motors |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104300777B (en) | A kind of inverter synchronization combination method | |
| CN102545257B (en) | Solar photovoltaic generating single-phase grid-connected inverter and control method thereof | |
| CN102916437B (en) | The soft combination method of a kind of grid-connected converter | |
| CN104038088B (en) | Method and device for controlling photovoltaic inverter circuit | |
| CN102969882B (en) | Starting method of modular multi-level flexible direct-current transmission converter | |
| US9793788B2 (en) | Energy storage system for renewable energy source | |
| CN102222937B (en) | Photovoltaic grid-connected inverter and grid-connected control method thereof | |
| US9882385B2 (en) | System for starting large-scale power load in micro-grid | |
| CN103915856B (en) | A kind of base station is grid-connected-charging photovoltaic micro-inverter system and control method thereof | |
| CN102244466B (en) | Voltage sag generator | |
| CN102904286B (en) | Grid-connected inverter and control method thereof | |
| CN104009497B (en) | A kind of LVRT Capability of Wind Turbine Generator and active power filter compensating device and changing method | |
| CN103051281A (en) | High-performance four-quadrant frequency converter | |
| US20120025609A1 (en) | Very high efficiency uninterruptible power supply | |
| CN104901410A (en) | UPS circuit | |
| CN105356784A (en) | Grid connected inverter with DC bus voltage balance function | |
| CN203747688U (en) | Three-level grid-connected inverter | |
| CN204179938U (en) | The synchronous grid-connected system of a kind of inverter | |
| CN204190636U (en) | PWM rectifier circuit topological structure | |
| CN105633994A (en) | Starting method of FMMC-LCC hybrid DC power transmission system | |
| CN103560523A (en) | Photovoltaic generator set low-voltage ride-through supporting system based on DVR | |
| CN104993687A (en) | Start control method of grid-connected inverter | |
| CN102545646B (en) | Abnormal voltage ride-through power supply of frequency converter | |
| CN109873487B (en) | Master-slave backup method for three-phase three-level VIENNA rectifier | |
| CN104052321B (en) | Mixing control method and its system that a kind of micro- inverter zero crossing current distortion suppresses |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee | ||
| CP01 | Change in the name or title of a patent holder |
Address after: Shenzhen Nanshan District City, Guangdong province 518055 White Pine Road Baiwang letter two Industrial Park District building seventh Patentee after: SHENZHEN WINLINE TECHNOLOGY CO., LTD. Address before: Shenzhen Nanshan District City, Guangdong province 518055 White Pine Road Baiwang letter two Industrial Park District building seventh Patentee before: Shenzhen Winline Technology Co., Ltd. |