CN104333242A - High-power DC source used for testing of photovoltaic grid-connected inverter - Google Patents
High-power DC source used for testing of photovoltaic grid-connected inverter Download PDFInfo
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- CN104333242A CN104333242A CN201410527344.8A CN201410527344A CN104333242A CN 104333242 A CN104333242 A CN 104333242A CN 201410527344 A CN201410527344 A CN 201410527344A CN 104333242 A CN104333242 A CN 104333242A
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- 238000012360 testing method Methods 0.000 title claims abstract description 34
- 238000004891 communication Methods 0.000 claims description 18
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- 238000010276 construction Methods 0.000 claims description 3
- 239000013307 optical fiber Substances 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 230000004044 response Effects 0.000 abstract description 5
- 230000006870 function Effects 0.000 description 6
- 230000005611 electricity Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M5/4585—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only having a rectifier with controlled elements
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- H02J3/383—
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- 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
- Y02B10/00—Integration of renewable energy sources in buildings
- Y02B10/10—Photovoltaic [PV]
-
- 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
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The invention discloses a high-power DC source used for testing of a photovoltaic grid-connected inverter. Two sets of parallel-connected three-phase full-bridge controllable rectification circuits are adopted so that input voltage range is wider, adaptability is higher, high-power DC can be outputted, level of the outputted DC voltage can be adjusted according to test requirements, and output power can meet the capacity requirement of domestic inverters. The outputted DC voltage is smooth and stable in waveform and common mode voltage to the ground is low. DC voltage response time is short, voltage build-up rate is 80V/s, impact to equipment is low and voltage overshoot amount is 0V so that the tested equipment is ensured to be safe and reliable. DC output adopts parallel-connected output of two paths of DC800A circuit breakers so that DC allowance is high, and a tripping phenomenon does not occur when the tested inverter is overloaded for 1.1 times.
Description
Technical field
The present invention relates to a kind of photovoltaic combining inverter test high power DC source.
Background technology
Because haze weather, Environment Pollution Event frequently occur, country vigorously supports renewable and clean energy resource industry development, and wind-powered electricity generation industry is thorough growth: within 2014, to the year two thousand twenty, will increase 2,000 ten thousand kilowatts of (20GW) installed capacitys newly every year.Photovoltaic industry situation is favourable: within 2014, national working energy can be gone up, National Energy Board has formulated the plan that domestic photovoltaic increases installation 14GW newly in 2014, along with the popularization of photovoltaic plant, the further expansion in photovoltaic DC-to-AC converter market will be impelled, and the expansion in photovoltaic DC-to-AC converter market, the year output of photovoltaic combining inverter is increasing year by year, and current most inverter measurement is also in the interim environment built at scene, for better, meet the testing requirement of photovoltaic DC-to-AC converter faster, development is needed to be exclusively used in the test macro of photovoltaic combining inverter test and required testing power supply thereof.
Chinese Patent Application No. is 201320448910.7 and 201320300928.2 disclose a kind of high power DC current transformer, be mainly DC fan and service is provided, its power output is relatively little, effectively can not build the power test platform of photovoltaic converter, cannot meet test demand.
Summary of the invention
The object of this invention is to provide a kind of photovoltaic combining inverter test high power DC source, to meet the testing requirement of existing photovoltaic combining inverter.
In order to realize above object, the technical solution adopted in the present invention is: a kind of photovoltaic combining inverter test high power DC source, comprise the rectification circuit for being connected with three phase network, described rectification circuit is made up of the three phase full bridge controlled rectification circuit of two groups of parallel connections, and the output of rectification circuit has two direct current output interfaces for being connected with inverter direct-flow input end to be measured in parallel.
LCL filter circuit is provided with between described rectification circuit and three phase network.
DC side and the AC of described rectification circuit are respectively equipped with electromagnetic interface filter.
Circuit between described rectification circuit and three phase network is provided with A.C. contactor, described A.C. contactor is parallel with a soft starting circuit.
The output of described rectification circuit connects with corresponding two Parallel opertation interfaces respectively by two DC circuit breakers.
This DC source also comprises control loop, and described control loop adopts modular construction, and comprise sampling conditioning unit, main control unit, input and output unit, communication unit, power module unit, each unit module is relatively independent, and inter-module communication is optical-fibre communications.
This DC source also comprises measure loop, and this measure loop adopts Hall element to change primary circuit signal into secondary circuit signal.
The core in photovoltaic combining inverter test high power DC source of the present invention is the three phase full bridge controlled rectification circuit of two groups of parallel connections, input voltage range is wider, adaptability is stronger, high power DC electricity can be exported, and the DC voltage level exported can regulate according to test demand, scope is 450V-850V, and voltage-regulation step-length is 1V.Maximum active power can reach 630kW, has 1.1 times of overload capacity.The maximum power of current domestic photovoltaic combining inverter is 630kW, and power output can meet the capacity requirement of domestic inverter; Its DC voltage waveform smooth steady exported, common-mode voltage is little over the ground.The direct voltage response time is fast, and voltage build-up rate is 80V/s, impacts little to equipment; Voltage overshoot is 0V, ensures the safe and reliable of equipment under test.
Direct current exports and adopts two-way direct current 800A circuit breaker Parallel opertation, and direct current allowance is large, there will not be trip phenomenon during tested inverter 1.1 times overload.
Accompanying drawing explanation
Fig. 1 is the circuit topology figure of DC source of the present invention;
Fig. 2 is the control logic schematic diagram of DC source of the present invention;
Fig. 3 is direct voltage response curve;
Fig. 4 is direct voltage curvilinear motion figure in start-up course;
Fig. 5 is main circuit current figure in start-up course.
Embodiment
Below in conjunction with accompanying drawing and specific embodiment, the present invention is described further.
By analyzing the conventionally test principle of whole photovoltaic combining inverter rated power circulation test, the rated power test of photovoltaic combining inverter and some type approval tests require that the input voltage grade of the DC source of photovoltaic combining inverter must can simulate the normal voltage grade of on-the-spot cell panel, and direct voltage is adjustable, can provide pure DC power supply, prevent from disturbing photovoltaic combining inverter; DC source also can the reliable direct current of stable output normally when 1.1 times of overloads for photovoltaic combining inverter.Therefore, high power DC source of the present invention just need when direct voltage can quick adjustment, require its perfect in shape and function, conveniently moving, simple to operate, protect complete.
Be illustrated in figure 1 the circuit topology figure of photovoltaic combining inverter test high power DC source apparatus embodiment of the present invention, as seen from the figure, this device comprises the rectification circuit for being connected with three phase network, rectification circuit is made up of the three phase full bridge controlled rectification circuit of two groups of parallel connections, and the output of rectification circuit has two direct current output interfaces for being connected with inverter direct-flow input end to be measured in parallel.
The each brachium pontis of rectification circuit has 3 rectification modules to form, and amounts to 6 rectification modules; Each module is made up of IGBT module, radiator, temperature element, 9 metal film electric capacity.Each brachium pontis can independent operating, and each bridge arm moduleization design, maintains easily.This device is mainly used in the test such as the test of rated power circulation, stress_responsive genes, power factor test, efficiency test of photovoltaic combining inverter.
The output of DC source rectification circuit of the present invention connects with corresponding two Parallel opertation interfaces respectively by two DC circuit breakers QF11, QF12, direct current exports and adopts two-way direct current 800A circuit breaker Parallel opertation, direct current allowance is large, there will not be trip phenomenon during tested inverter 1.1 times overload.
For reducing DC source to the impact of tested product, DC side and the AC of DC source rectification circuit increase electromagnetic interface filter respectively, i.e. the ACEMI of AC and the DCEMI of DC side, to reduce the interference to detected element.
Can independent operating for meeting two groups of rectifier bridges, all monitoring is had to the input current of each module of DC source in the present invention, for increasing the useful life of DC source, when power organizes 80% of brachium pontis rated power lower than list, DC source can selectively use wherein one group of brachium pontis to export according to demand, and another group is in standby mode.When operation brachium pontis breaks down suddenly or power exceedes the limit value of single group brachium pontis, namely standby brachium pontis puts into operation, ensures the Stability and dependability exported.
High power DC source apparatus of the present invention, except rectification circuit, also comprises filter circuit, measure loop, control loop, heat-radiation loop, electric power loop, and device bottom is fixed on channel-section steel, facilitates the transhipment of fork truck.Because this device is testing equipment, be mainly used in indoor, design degree of protection is IP20.
Be provided with the LCL filter circuit be made up of L1 ~ L3 and capacitance group C1 between rectification circuit and three phase network, ensure that high-power electric and electronic circuit harmonizing wave can not pollute electrical network, and then affect the normal operation of neighbouring device.
Measure loop adopts Hall element to change primary circuit signal into secondary circuit signal.
Control loop adopts modular construction, and comprise sampling conditioning unit, main control unit, input and output unit, communication unit, power module unit, each unit module is relatively independent, and inter-module communication is optical-fibre communications, prevents mutual interference.Wherein, main control unit is data processing unit, in real time with each unit communications, is exchanged send instruction by each cell data, when parameter exceeds reference value, and meeting trigger software defencive function, thus ensure that DC source is stable.Data processing unit is the filter amplification circuit of weak electric signal, is built-in with protective circuit, can trigger the hardware protection function of DC source.
This device communication modes is various, can realize local and remote two ends and control.Communication unit adopts RS485 communication modes and touch-screen communication; Communication unit reserves 2 passages, and one of them channel communications agreement is RS485, and wiring is reserved in external terminal board place; Another channel communications agreement is that RS232, RS232 communications protocol is converted into 104 agreements outputs through gateway.
This DC source device adopts air blast cooling mode to dispel the heat, and ensures that module temperature remains on optimum working temperature, improves the useful life of module and the transformation efficiency of inverter.
This device controls the scheme that electric power loop adopts multiple power supplies seamless switching, and the uninterrupted power supply of Guarantee control system, guarantees the stability that equipment runs.
Current-source arrangement of the present invention has hardware protection and software protection two to overlap protection system; guarantee unit protection perfect in shape and function; have the protection of interchange overvoltage/undervoltage, DC over-voltage protection, AC overcurrent protection, direct current overcurrent protection, overheat protector, overload protection, driving malfunction protection, unbalance protection of three-phase current, DC earthing protection, cross the functions such as underfrequency protection, perfect defencive function ensure that equipment safety runs reliably.As shown in Figure 1, be provided with AC earth protective circuit at AC, this circuit be serially connected with circuit breaker Q F5 and fuse FV2; Be provided with DC protection circuit in DC side, this circuit be serially connected with resistance R41 and contactor KM1.
The present invention adopts pid algorithm to the control technology of direct voltage, issues command voltage by touch-screen to device, and DC source control system exports adjustable direct voltage accurately by SVPWM control technology, and control logic as shown in Figure 2.The present invention is fast to direct voltage response, precision is high, overshoot is 0V substantially.Direct voltage response curve as shown in Figure 3.
As shown in Figure 1, the circuit between rectification circuit of the present invention and three phase network is provided with circuit breaker Q F3, A.C. contactor KM3, A.C. contactor KM3 is parallel with one by contactor KM2 and corresponding resistance R42 ~ R44 soft starting circuit in series.Soft the open loop in parallel with A.C. contactor first be closed to DC side precharge when this device starts; Closed A.C. contactor KM3 after completing precharge, disjunction is soft opens loop; Master control borad exports pwm pulse control direct voltage according to instruction and reaches command value.In start-up course, DC bus-bar voltage curve as shown in Figure 4, and main circuit current curve as shown in Figure 5.
DC source device of the present invention can export 450V-850V adjustable DC electricity, power can reach 630kVA, the input voltage range of this device is wider, adaptability is comparatively strong, is not with transformer type inverter (domestic transformer type inverter ac voltage of not being with is 315V and 270V) to be equipped with an isolating transformer namely satisfies the demands for domestic order first two; Only need to increase a step-up transformer at the AC of DC source to band transformer type inverter, simple to operate, easy to maintenance.
This device man-machine interface is friendly, and touch-screen shows, convenient operation.Remote measurement amount, remote signalling amount, remote regulating amount, remote control are all by touch-screen display, and precision is higher.Touch-screen and local control hardware have certain memory function, can show DC voltage waveform, and the power curve of the output of electric energy.
Above embodiment only understands core concept of the present invention for helping; the present invention can not be limited with this; for those skilled in the art; every according to thought of the present invention; the present invention is modified or equivalent replacement; any change done in specific embodiments and applications, all should be included within protection scope of the present invention.
Claims (7)
1. high power DC source is used in a photovoltaic combining inverter test, it is characterized in that: comprise the rectification circuit for being connected with three phase network, described rectification circuit is made up of the three phase full bridge controlled rectification circuit of two groups of parallel connections, and the output of rectification circuit has two direct current output interfaces for being connected with inverter direct-flow input end to be measured in parallel.
2. photovoltaic combining inverter test high power DC source according to claim 1, is characterized in that: be provided with LCL filter circuit between described rectification circuit and three phase network.
3. photovoltaic combining inverter test high power DC source according to claim 1, is characterized in that: DC side and the AC of described rectification circuit are respectively equipped with electromagnetic interface filter.
4. photovoltaic combining inverter test high power DC source according to claim 1, is characterized in that: the circuit between described rectification circuit and three phase network is provided with A.C. contactor, described A.C. contactor is parallel with a soft starting circuit.
5. photovoltaic combining inverter test high power DC source according to claim 1, is characterized in that: the output of described rectification circuit connects with corresponding two Parallel opertation interfaces respectively by two DC circuit breakers.
6. photovoltaic combining inverter test high power DC source according to claim 1, it is characterized in that: this DC source also comprises control loop, described control loop adopts modular construction, comprise sampling conditioning unit, main control unit, input and output unit, communication unit, power module unit, each unit module is relatively independent, and inter-module communication is optical-fibre communications.
7. photovoltaic combining inverter test high power DC source according to claim 1, is characterized in that: this DC source also comprises measure loop, and this measure loop adopts Hall element to change primary circuit signal into secondary circuit signal.
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| CN201410527344.8A CN104333242A (en) | 2014-10-09 | 2014-10-09 | High-power DC source used for testing of photovoltaic grid-connected inverter |
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| CN201410527344.8A CN104333242A (en) | 2014-10-09 | 2014-10-09 | High-power DC source used for testing of photovoltaic grid-connected inverter |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107132440A (en) * | 2017-05-23 | 2017-09-05 | 江苏现代电力科技股份有限公司 | A kind of power electronics type reactor performance testing device |
| CN108631367A (en) * | 2018-06-26 | 2018-10-09 | 哈尔滨工业大学 | A kind of grid-connected rectifier DC voltage adjusting method based on linear disturbance observer |
| CN113964832A (en) * | 2021-11-01 | 2022-01-21 | 青岛鼎信通讯股份有限公司 | Topology for reducing influence of power quality equipment on carrier meter reading |
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| CN203398798U (en) * | 2013-06-26 | 2014-01-15 | 许继电气股份有限公司 | Large power energy storage converter and main circuit thereof |
| CN103605014A (en) * | 2013-10-23 | 2014-02-26 | 国家电网公司 | Test platform for large energy storage converters |
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Patent Citations (5)
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| US20080122293A1 (en) * | 2006-10-13 | 2008-05-29 | Pv Powered, Inc. | System and Method for Anti-Islanding, Such as Anti-Islanding for a Grid-Connected Photovoltaic Inverter |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108631367A (en) * | 2018-06-26 | 2018-10-09 | 哈尔滨工业大学 | A kind of grid-connected rectifier DC voltage adjusting method based on linear disturbance observer |
| CN108631367B (en) * | 2018-06-26 | 2021-08-03 | 国网黑龙江省电力有限公司绥化供电公司 | Grid-connected rectifier direct-current voltage adjusting method based on linear interference observer |
| CN113964832A (en) * | 2021-11-01 | 2022-01-21 | 青岛鼎信通讯股份有限公司 | Topology for reducing influence of power quality equipment on carrier meter reading |
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Application publication date: 20150204 |