Utility model content
In view of this, the application's object is the group string data photovoltaic system that a kind of power optimization device is provided and applies it, with solve existing by bypass diode carry out the method power consumption of power optimization large, control the large problem of difficulty.
For achieving the above object, the application provides following technical scheme:
A kind of power optimization device, is applied to group string data photovoltaic system, and described group of string data photovoltaic system comprises the photovoltaic module with multiple cell panels that are connected in series, and inverter, comprising:
Centralized Controller, and the power regulation mechanism being connected in parallel with described photovoltaic module;
Described power regulation mechanism comprises multiple Energy Transfer circuit;
Between two cell panels of arbitrary neighborhood, be provided with a described Energy Transfer circuit, multiple described Energy Transfer circuit are connected in series; The first port of described Energy Transfer circuit is connected with the common port of described adjacent two cell panels; Described Energy Transfer circuit comprises a communication module communicating with described Centralized Controller.
Preferably, described Energy Transfer circuit comprises bidirectional direct current converter.
Preferably, described bidirectional direct current converter comprise following any one: bidirectional voltage boosting circuit, two-way step down circuit and Bidirectional up-down volt circuit.
Preferably, the communication module of described Energy Transfer circuit comprises wireless communication module.
A kind of group string data photovoltaic system, comprises the photovoltaic module with multiple cell panels that are connected in series, and inverter, also comprises the power optimization device described in above any one.
Can find out from above-mentioned technical scheme, when difference appears in the output characteristic of the different cell panels of the application in photovoltaic module, by the corresponding Energy Transfer circuit of the difference current trigger between this cell panel there are differences; This Energy Transfer circuit transfers to by the high cell panel of generated output the cell panel that generated output is low by electric energy; With respect to directly more electric energy being consumed by bypass diode in prior art, the embodiment of the present application has reduced the power loss of light power generating system greatly, improve its generating efficiency, and determine a peak power output by Centralized Controller, eliminate local maximum power point, reduced control difficulty.Therefore, the embodiment of the present application has solved the problem of prior art.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present application, the technical scheme in the embodiment of the present application is clearly and completely described, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiment.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtaining under creative work prerequisite, all belong to the scope of the application's protection.
The embodiment of the present application discloses a kind of power optimization device and has applied its group string data photovoltaic system, with solve existing by bypass diode carry out the method power consumption of power optimization large, control the large problem of difficulty.
With reference to Fig. 1, the power optimization device that the embodiment of the present application one provides, is applied to a kind of group string data photovoltaic system, and this group string data photovoltaic system comprises photovoltaic module 100, and inverter 200; Photovoltaic module 100 has multiple cell panels that are connected in series, the DC side of inverter 200 is connected with the output of photovoltaic module 100, the AC of inverter 200 is connected with electrical network 300, and the direct current that inverter 200 is exported photovoltaic module 100 is converted to alternating current, is connected to the grid 300.
This power optimization device comprises: Centralized Controller 410 and power regulation mechanism 420.
Concrete, Centralized Controller 410 is for according to the output voltage V of photovoltaic module 1000with output current i0really state the current peak power output of photovoltaic module 100, and generate one and meet the switching signal that described current peak power output requires.
Power regulation mechanism 420 is connected in parallel with photovoltaic module 100; Power regulation mechanism 420 comprises multiple Energy Transfer circuit 421 that are connected in series, two cell panels of arbitrary neighborhood are provided with an Energy Transfer circuit 421, if i.e.: total n the cell panel of photovoltaic module 1, power regulation mechanism 420 should at least have n-1 Energy Transfer circuit 421.
Energy Transfer circuit 421 is provided with 3 ports, and wherein the first port is connected with the common port of corresponding adjacent two cell panels, and the second port for being connected with other Energy Transfer circuit 421, forms series circuit, i.e. power regulation mechanism 420 with the 3rd port.Energy Transfer circuit 421 is also provided with a communication module, for communicating with Centralized Controller 410.Energy Transfer circuit 421, flows through according to the difference electric current between adjacent two cell panels described in described switching signal control for multiple in the time that between adjacent two cell panels, electric current is inconsistent
The operation principle of above-mentioned power optimization device is as follows:
In the time that the output characteristic of n cell panel in photovoltaic module 100 is consistent, the output current i of each cell panelk(k=1,2 ..., n) all with the output current i of photovoltaic module0equate i.e. i1=i2=...=in=i0, be also that between adjacent two cell panels, no current is poor, therefore no current flows into Energy Transfer circuit 421, Energy Transfer circuit 421 is bypassed, and does not carry out Energy Transfer.
When certain or certain several cell panels in photovoltaic module 100, owing to being caused by reasons such as shade block, photoelectric effect weakens, generated output is while lowering, its output current also reduces, thereby and producing a difference electric current between the output current of cell panel adjacent, that be not blocked, this difference electric current flows into corresponding Energy Transfer circuit 421 by the common port of above-mentioned adjacent two cell panels that there are differences.
In Energy Transfer circuit 421, be provided with power switch, in the time that the first port of Energy Transfer circuit 421 has electric current to flow into, described in the switching signal control that Energy Transfer circuit 421 produces according to Centralized Controller 410, power switch opening and closing, thereby control flowing through of described difference electric current, realize electric energy is transferred to the cell panel that generated output is low (low-pressure side) by the high cell panel of generated output (high-pressure side), realize the power optimization to adjacent two cell panels, part is optimized, and makes its output characteristic consistent; Multiple Energy Transfer circuit 421 actings in conjunction make the output characteristic of two cell panels of arbitrary neighborhood all consistent, the output characteristic that has realized all cell panels in photovoltaic module 100 is consistent, make the power of photovoltaic module 100 reach described current peak power output, thereby ensured the maximizes power of photovoltaic module 100.
In addition, the switching signal of controlling Energy Transfer circuit 421 is generated according to the peak power output of photovoltaic module 100 by Centralized Controller 410, thereby has ensured that photovoltaic module 100 is operated in maximum power point place.
From said structure and operation principle, when difference appears in the output characteristic of the different cell panels of the embodiment of the present application in photovoltaic module, by the corresponding Energy Transfer circuit of the difference current trigger between this cell panel there are differences; This Energy Transfer circuit transfers to by the high cell panel of generated output the cell panel that generated output is low by electric energy; With respect to directly more electric energy being consumed by bypass diode in prior art, the embodiment of the present application has reduced the power loss of light power generating system greatly, improve its generating efficiency, and determine a peak power output by Centralized Controller, eliminate local maximum power point, reduced control difficulty.Therefore, the embodiment of the present application has solved the problem of prior art.
Preferably, in the embodiment of the present application, Energy Transfer circuit comprises bidirectional direct current converter (two-way DC/DC circuit); More specifically, bidirectional direct current converter can be following any one: bidirectional voltage boosting circuit (two-way Boost circuit), two-way step down circuit (two-way Buck circuit) and Bidirectional up-down volt circuit (two-way Buck-Boost circuit).
In the embodiment of the present application, the communication module in Energy Transfer circuit is preferably wireless communication module, communicates by communication and Centralized Controller, obtains the switching signal that Centralized Controller produces.
In addition, in the embodiment of the present application, Centralized Controller can arrange separately, as a controller independently; Also can be integrated in inverter.
In addition, the embodiment of the present application also provides a kind of group of string data photovoltaic system, comprises photovoltaic module, the inverter with multiple cell panels that are connected in series, and power optimization device described in above-described embodiment.With respect to directly more electric energy being consumed by bypass diode in prior art, the embodiment of the present application is carried out Partial Power optimization by this power optimization device to photovoltaic module, greatly reduce the power loss of light power generating system, improve its generating efficiency, and determine a peak power output by Centralized Controller, eliminate local maximum power point, reduced control difficulty, solved the problem of prior art.
It should be noted that, in this article, relational terms such as the first and second grades is only used for an entity or operation to separate with another entity or operating space, and not necessarily requires or imply and between these entities or operation, have the relation of any this reality or sequentially.
Each embodiment in this specification all adopts the mode of going forward one by one to describe, between each embodiment identical similar part mutually referring to, what each embodiment stressed is and the difference of other embodiment.To the above-mentioned explanation of the disclosed embodiments, make professional and technical personnel in the field can realize or use the application.To be apparent for those skilled in the art to the multiple amendment of these embodiment, General Principle as defined herein can, in the case of not departing from the application's spirit or scope, realize in other embodiments.Therefore, the application will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.