CN104578171B - A kind of control method of direct current photovoltaic generating module - Google Patents
A kind of control method of direct current photovoltaic generating module Download PDFInfo
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- CN104578171B CN104578171B CN201510073364.7A CN201510073364A CN104578171B CN 104578171 B CN104578171 B CN 104578171B CN 201510073364 A CN201510073364 A CN 201510073364A CN 104578171 B CN104578171 B CN 104578171B
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- 238000005286 illumination Methods 0.000 claims description 9
- 238000012423 maintenance Methods 0.000 claims description 4
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- 230000015572 biosynthetic process Effects 0.000 abstract description 5
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- 238000010248 power generation Methods 0.000 abstract description 2
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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
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- 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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Abstract
The present invention relates to the control method of a kind of direct current photovoltaic generating module, belong to technical field of photovoltaic power generation.The method includes constituting photovoltaic generating system initially with by direct current photovoltaic generating module, GPRS module, dc bus, inverter, AC network, all described direct current photovoltaic generating modules are carried out parallel connection as elementary cell, and be all connected with described dc bus, all direct current photovoltaic generating modules are divided into some groups simultaneously, often group is containing n direct current photovoltaic generating module and a GPRS module, realizes radio communication with host computer；Secondly fault detect and judgement are carried out according to photovoltaic module output voltage and direct current photovoltaic generating module output；The final duty determining each direct current photovoltaic generating module according to DC bus-bar voltage.Present configuration is simple, control flexible and convenient, and fault diagnosis and location are quick, accurate, can thoroughly solve the hot spot effect of the formation such as shade, it is achieved generating efficiency maximizes, and is especially suitable for distributed photovoltaic power station.
Description
Technical field
The present invention relates to a kind of control method, the control method of a kind of direct current photovoltaic generating module, belong to technical field of photovoltaic power generation.
Background technology
The most conventional photovoltaic generating system mainly has the organization plans such as centralized, tandem, multiple branch circuit formula, but its shortcoming is: system exists the serial or parallel connection of photovoltaic module, the MPPT maximum power point tracking of system is for whole connection in series-parallel photovoltaic array or component string, cannot ensure that each assembly all operates in maximum power point, anti-shade ability, possibly even form hot spot, assembly is caused to damage, system reliability is low, greatly reduce the effciency of energy transfer of system, be also difficult to obtain the status information of each assembly simultaneously.
For disadvantages mentioned above, document is had to point out to use DC Module formula organization plan.
CN103095180A discloses a kind of Intelligent photovoltaic module and control method thereof, the method is maximum power output unified control method, that is: photovoltaic cell group and DC-DC converter are connected to form photovoltaic module, then these photovoltaic modules are cascaded, it is uniformly controlled each DC-DC converter (for Buck circuit), to ensureing that each photovoltaic cell group is operated in its output optimum point under the conditions of any exterior light is shone by a shared maximal power tracing unit.The method yet suffers from above-mentioned tandem photovoltaic system defect, and there is the problems such as system structure is complicated, it is difficult to control, construction difficulty, is also difficult to obtain the status information of each assembly simultaneously.
CN102158094B discloses the control method of a kind of photovoltaic generation DC-DC converter, the method is that several DC-AC inverter connect a high frequency transformer respectively, one end of the secondary side of all high frequency transformers connects together, the other end connects single-phase diode respectively and realizes rectification, forms photovoltaic generation DC-DC converter.When the output voltage of some photovoltaic array module is zero or is much smaller than the output of other photovoltaic array module when the output of some photovoltaic array module, need to adjust the phase angle of each DC-AC changer in N phase photovoltaic generation DC-DC converter；And when in grid-connected photovoltaic system, several photovoltaic array module generation problems make its peak power exported decline to a great extent, the number of phases of photovoltaic generation DC-DC converter does not adjusts, but the meansigma methods of the output voltage of the photovoltaic array module of generation problem to be adjusted all normal photovoltaic array module output voltages that are other.There is system structure complexity, control complicated, construction difficulty, high in cost of production problem in this photovoltaic generation DC-DC converter visible and control method thereof, does not relates to the communication issue of each changer.
Summary of the invention
Present invention is primarily targeted at: the shortcoming existed for above-mentioned prior art, there is provided a kind of simple in construction, control more flexible and convenient, be prone to construction, the control method of a kind of direct current photovoltaic generating module that intelligent level is high, by each photovoltaic generating module is carried out parallel connection as elementary cell, thoroughly solve the hot spot effect of the formation such as shade, realize under any illumination condition, especially under not mating illumination condition, the generating efficiency of photovoltaic generating system maximizes.
The present invention solves this technical problem and be the technical scheme is that
A kind of direct current photovoltaic generating module, it is made up of photovoltaic module, DC micro changer, communication module, described DC micro changer one end is connected with described photovoltaic module, the other end is connected with described dc bus, described DC micro changer connects the control loop having self, and described control loop is connected with described communication module, it is achieved DC boosting, MPPT maximum power point tracking (MPPT) and communication function, thoroughly solve the hot spot effect of the formation such as shade, be greatly improved generating efficiency.
Described DC micro changer uses DC-AC-DC structure, first pass through DC-AC inversion, the direct current energy that photovoltaic module exports is transformed to AC energy, is then brought the voltage up by high frequency transformer, again by AC-DC rectification, the output voltage of photovoltaic module is increased to required DC voltage.
The control method of the present invention a kind of direct current photovoltaic generating module, it is characterised in that comprise the following steps:
Step 1, above-mentioned a kind of direct current photovoltaic generating module uses following connected mode in photovoltaic generating system:
1) photovoltaic generating system includes direct current photovoltaic generating module, GPRS module, dc bus, inverter, AC network；All described direct current photovoltaic generating modules carry out parallel connection as elementary cell, and are all connected with described dc bus, carried by electric energy, converge to described dc bus；Described inverter one end is connected with described dc bus, and direct current energy is transformed to AC energy, and the described inverter other end is connected with described AC network, it is achieved grid-connected；
2) described direct current photovoltaic generating modules all in photovoltaic generating system are divided into some groups；Often group is containing n direct current photovoltaic generating module (wherein n≤255) and a described GPRS module, and the GPRS module that each direct current photovoltaic generating module all uses RS485 bus to organize with this by its communication module is connected；The GPRS module often organized and host computer realize radio communication, gather and upload the status information of this group all direct currents photovoltaic generating module, also assign the host computer instruction to each direct current photovoltaic generating module simultaneously, realize the monitoring and fault diagnosis of all direct current photovoltaic generating modules, facilitate system maintenance.
Step 2, photovoltaic generating system run in the fault detect of direct current photovoltaic generating module and judgement:
1) the output voltage approximately equal of each photovoltaic module, shows that all photovoltaic modulies are working properly；
2) in the case of normal illumination, when the output of some direct current photovoltaic generating module is much smaller than the output of its neighbouring direct current photovoltaic generating module, show that the photovoltaic module of this direct current photovoltaic generating module occurs in that the problem that assembly itself damages, covered by the foreign material such as local shades, birds droppings, or show that the DC micro changer of this direct current photovoltaic generating module breaks down, now send alarm signal；
3) in the case of normal illumination, when host computer does not receives one or more direct current photovoltaic generating module data, show that the communication module of these direct current photovoltaic generating modules or the GPRS module of its place group break down, now send alarm signal.
Step 3, determines the duty of direct current photovoltaic generating module:
1) DC bus-bar voltage is monitored all the time；
2) when DC bus-bar voltage normal range (such as: its rated voltage ± 15%) in, each direct current photovoltaic generating module is operated under MPPT state, and photovoltaic generating system is in normal operating condition；
3) when DC bus-bar voltage is higher than a certain limit value (such as the 115% of its rated voltage), each direct current photovoltaic generating module will exit MPPT state successively, enter constant voltage duty, until DC bus-bar voltage is in allowed limits, now, remaining direct current photovoltaic generating module still remains operating in original duty；
4) when DC bus-bar voltage is higher than its higher limit (such as the 120% of its rated voltage); each direct current photovoltaic generating module will work in stopped status successively; until DC bus-bar voltage is in allowed limits, now, remaining direct current photovoltaic generating module remains operating in original duty.
Compared with prior art, the invention has the beneficial effects as follows:
1) direct current photovoltaic generating module has independent MPPT maximum power point tracking function, can ensure that each photovoltaic module all operates in maximum power point, direct current photovoltaic generating module has the highest anti-local shades and assembly electric parameter mismatch capability, can thoroughly solve the hot spot effect of the formation such as shade, drastically increase photovoltaic generating system output under not mating illumination condition, it is achieved that the generating efficiency of photovoltaic generating system maximizes；
2) simple in construction, control more flexible and convenient；
3) fault diagnosis and fault location are quick, accurate, and system maintenance easy is greatly shortened downtime, further increases system generating efficiency, and drastically increase the intelligent level of photovoltaic generating system.
Accompanying drawing explanation
Fig. 1 is the composition schematic diagram of the present invention a kind of direct current photovoltaic generating module.
Fig. 2 is the system pie graph of control method of the present invention.
Wherein, 1-direct current photovoltaic generating module；2-GPRS module；3-dc bus；4-inverter；5-AC network；101-photovoltaic module；102-DC micro changer；103-communication module.
Detailed description of the invention
Below in conjunction with the accompanying drawings, the present invention is described in further detail.
As shown in Figure 1, the control method of the present invention a kind of direct current photovoltaic generating module, described direct current photovoltaic generating module 1 is by photovoltaic module 101, DC micro changer 102, communication module 103 forms, DC micro changer 102 one end is connected with photovoltaic module 101, the other end is connected with dc bus 3, DC micro changer 101 connects the control loop having self, described control loop communicates with module 103 and is connected, realize DC boosting, MPPT maximum power point tracking (MPPT) and communication function, thoroughly solve the hot spot effect of the formation such as shade, it is greatly improved system generating efficiency.
DC micro changer 102 uses DC-AC-DC structure, first pass through DC-AC inversion, the direct current energy that photovoltaic module exports is transformed to AC energy, then brought the voltage up by high frequency transformer, again by AC-DC rectification, the output voltage of photovoltaic module is increased to required DC voltage (such as 800V or 400V).
As shown in Figure 2, the control method of the present invention a kind of direct current photovoltaic generating module, specifically include following steps:
Step 1, above-mentioned a kind of direct current photovoltaic generating module 1 uses following connected mode in photovoltaic generating system:
1) photovoltaic generating system includes direct current photovoltaic generating module 1, GPRS module 2, dc bus 3, inverter 4, AC network 5；Direct current photovoltaic generating modules 1 all in photovoltaic generating system are carried out parallel connection as elementary cell, and is all connected with dc bus 3, electric energy is carried, converges to dc bus 3；One end of inverter 4 is connected with dc bus 3, and direct current energy is transformed to AC energy, and the other end of inverter 4 is connected with AC network 5, it is achieved grid-connected；
2) direct current photovoltaic generating modules 1 all in photovoltaic generating system are divided into N group；Often group is containing n direct current photovoltaic generating module 1(wherein n≤255) and a GPRS module 2, the GPRS module 2 that each direct current photovoltaic generating module 1 all uses RS485 bus to organize with this by its communication module 103 is connected；GPRS module 2 and the host computer often organized realize radio communication, gather and upload the status information of this group all direct currents photovoltaic generating module 1, also assign the host computer instruction to each direct current photovoltaic generating module 1 simultaneously, realize the monitoring and fault diagnosis of all direct current photovoltaic generating modules 1, facilitate system maintenance.
Step 2, photovoltaic generating system run in the fault detect of direct current photovoltaic generating module 1 and judgement:
1) the output voltage approximately equal of each photovoltaic module 101, shows that all photovoltaic modulies 101 are working properly；
2) in the case of normal illumination, when the output of some direct current photovoltaic generating module 1 is much smaller than the output of its neighbouring direct current photovoltaic generating module 1, show that the photovoltaic module 101 of this direct current photovoltaic generating module 1 occurs in that the problem that assembly itself damages, covered by the foreign material such as local shades, birds droppings, or show that the DC micro changer 102 of this direct current photovoltaic generating module 1 breaks down, now send alarm signal；
3) in the case of normal illumination, when host computer does not receives the data of one or more direct current photovoltaic generating module 1, show that the communication module 103 of these direct current photovoltaic generating modules 1 or the GPRS module 2 of its place group break down, now send alarm signal.
Step 3, determines the duty of direct current photovoltaic generation electricity generation module 1:
1) voltage of dc bus 3 is monitored all the time；
2) when dc bus 3 voltage normal range (such as: its rated voltage ± 15%) in, each direct current photovoltaic generating module 1 is operated under MPPT state, and photovoltaic generating system is in normal operating condition；
3) when the voltage of dc bus 3 is higher than a certain limit value (such as the 115% of its rated voltage), each direct current photovoltaic generating module 1 will exit MPPT state successively, enter constant voltage duty, until the voltage of dc bus 3 is in allowed limits, now, remaining direct current photovoltaic generating module 1 still remains operating in original duty；
4) when the voltage of dc bus 3 is higher than its higher limit (such as the 120% of its rated voltage); each direct current photovoltaic generating module 1 will work in stopped status successively; until the voltage of dc bus 3 is in allowed limits; now, remaining direct current photovoltaic generating module 1 remains operating in original duty.
In addition to the implementation, the present invention can also have other embodiment.The technical scheme that all employing equivalents or equivalent transformation are formed, all falls within the protection domain of application claims.
Claims (1)
1. the control method of a direct current photovoltaic generating module, it is characterised in that comprise the following steps:
Step 1, a kind of direct current photovoltaic generating module uses following connected mode in photovoltaic generating system:
1) photovoltaic generating system includes direct current photovoltaic generating module, GPRS module, dc bus, inverter, AC network；All described direct current photovoltaic generating modules carry out parallel connection as elementary cell, and are all connected with described dc bus, carried by electric energy, converge to described dc bus；Described inverter one end is connected with described dc bus, and direct current energy is transformed to AC energy, and the described inverter other end is connected with described AC network, it is achieved grid-connected；
2) described direct current photovoltaic generating modules all in photovoltaic generating system are divided into some groups；Often group is containing not more than 255 direct current photovoltaic generating modules and a described GPRS module, and the GPRS module that each direct current photovoltaic generating module all uses RS485 bus to organize with this by its communication module is connected；The GPRS module often organized and host computer realize radio communication, gather and upload the status information of this group all direct currents photovoltaic generating module, also assign the host computer instruction to each direct current photovoltaic generating module simultaneously, realize the monitoring and fault diagnosis of all direct current photovoltaic generating modules, facilitate system maintenance；
Step 2, photovoltaic generating system run in the fault detect of direct current photovoltaic generating module and judgement:
1) the output voltage approximately equal of each photovoltaic module, shows that all photovoltaic modulies are working properly；
2) in the case of normal illumination, when the output of some direct current photovoltaic generating module is much smaller than the output of its neighbouring direct current photovoltaic generating module, show that the photovoltaic module of this direct current photovoltaic generating module occurs in that the problem that assembly itself damages, covered by local shades, foreign material, or show that the DC micro changer of this direct current photovoltaic generating module breaks down, now send alarm signal；
3) in the case of normal illumination, when host computer does not receives one or more direct current photovoltaic generating module data, show that the communication module of these direct current photovoltaic generating modules or the GPRS module of its place group break down, now send alarm signal；
Step 3, determines the duty of direct current photovoltaic generating module:
1) DC bus-bar voltage is monitored all the time；
2) when DC bus-bar voltage is within normal range, each direct current photovoltaic generating module is operated under MPPT state, and photovoltaic generating system is in normal operating condition；
3) when DC bus-bar voltage is higher than a certain limit value, each direct current photovoltaic generating module will exit MPPT state successively, enter constant voltage duty, until DC bus-bar voltage is in allowed limits, now, remaining direct current photovoltaic generating module still remains operating in original duty；
4) when DC bus-bar voltage is higher than its higher limit, each direct current photovoltaic generating module will work in stopped status successively, until DC bus-bar voltage is in allowed limits, now, remaining direct current photovoltaic generating module remains operating in original duty.
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| CN104821773A (en) * | 2015-05-05 | 2015-08-05 | 无锡联动太阳能科技有限公司 | Novel solar power generation system |
| CN107612008A (en) * | 2017-09-13 | 2018-01-19 | 河南省三禾电气有限公司 | Intelligence becomes distribution method and system |
| CN108111115A (en) * | 2017-11-24 | 2018-06-01 | 郑州中能光电设备有限公司 | The maintenance device and method of a kind of photovoltaic generation |
| CN107933356B (en) * | 2017-12-01 | 2020-10-02 | 扬州港信光电科技有限公司 | Power supply system of electric vehicle |
| CN113193595B (en) * | 2021-05-12 | 2023-01-06 | 丰郅(上海)新能源科技有限公司 | Safety management system and safety management method for photovoltaic module |
| CN113300596A (en) * | 2021-06-30 | 2021-08-24 | 阳光电源股份有限公司 | Photovoltaic power generation system and DC/DC converter control method thereof |
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| US20060237058A1 (en) * | 2005-04-25 | 2006-10-26 | Mcclintock Ronald B | Direct current combiner box with power monitoring, ground fault detection and communications interface |
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Effective date of registration: 20220125 Address after: 276800 No. 101, building 001, East Xuzhou Road, Chengdu Road, Rizhao Economic Development Zone, Shandong Province Patentee after: Shandong Yongjin Electric Co.,Ltd. Address before: 273165 Jingxuan West Road, Qufu City, Jining, Shandong Province, No. 57 Patentee before: QUFU NORMAL University Patentee before: Chu Xiaoguang |