Voltage stabilizer, junction box and photovoltaic system

Abstract

The invention relates to a voltage stabilizer, a junction box and a photovoltaic system. The voltage stabilizing device is used for being connected with a laminated cell structure, the laminated cell structure comprises a plurality of solar cell layers which are laminated and arranged at intervals, and the voltage stabilizing device comprises a plurality of conversion modules which are correspondingly connected with the plurality of solar cell layers respectively; the conversion module comprises a control chip and an electric energy conversion module; the control chip is respectively connected with the solar cell layer and the electric energy conversion module, and the electric energy conversion module is connected with the solar cell layer; the control chip is used for obtaining the maximum power point voltage of the solar cell layers according to the cell parameters of the solar cell layers and generating a control signal according to the maximum power point voltage, the cell parameters and target voltage corresponding to the solar cell layers, and the cell parameters of any two solar cell layers are different; the control signal is used for controlling the electric energy conversion module to generate output voltage according to battery parameters, and voltage difference between the output voltage and target voltage is within a preset range. And voltage regulation and matching are realized.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and particularly to a voltage stabilizing device, a junction box and a photovoltaic system. Background Art

[0002] For a mechanically stacked multi-terminal stacked cell structure, the voltage and current outputs of each layer of solar cells are separate and independent. The preparation of each layer of solar cells is based on its own optimal process, which can maximize the process advantages of each layer without considering the problem of process matching with each other, greatly reducing the process difficulty and production cost. However, the output voltages and output currents of each layer of solar cells are different. How to achieve voltage matching and regulation between the layers of solar cells in the multi-terminal stacked cell structure and maintain stable output and efficient energy transmission has become an urgent problem to be solved. Summary of the Invention

[0003] Based on this, in view of the above technical problems, it is necessary to provide a voltage stabilizing device, a junction box and a photovoltaic system, which can quickly achieve voltage matching and regulation between the layers of solar cells in the stacked cell structure and maintain stable output and efficient energy transmission.

[0004] A voltage stabilizing device for connecting to a stacked cell structure, the stacked cell structure including a plurality of solar cell layers stacked and spaced apart, the voltage stabilizing device comprising:

[0005] A plurality of conversion modules respectively connected to the plurality of solar cell layers; the conversion module comprising:

[0006] A control chip and a power conversion module; the control chip is respectively connected to the solar cell layer and the power conversion module, and the power conversion module is connected to the solar cell layer;

[0007] Wherein, the control chip is configured to obtain the maximum power point voltage of the solar cell layer according to the battery parameters of the solar cell layer, and generate a control signal according to the maximum power point voltage, the battery parameters and the target voltage corresponding to the solar cell layer, and the battery parameters of any two solar cell layers are different; the control signal is used to control the power conversion module to generate an output voltage according to the battery parameters, and the voltage difference between the output voltage and the target voltage is within a preset range.

[0008] In one embodiment, the battery parameters include battery voltage and battery current, and the conversion module further comprises:

[0009] A sampling unit, which is respectively connected to the control chip and the power conversion module, is configured to collect the output current of the power conversion module and generate a sampled current; wherein, the control chip is further configured to determine the change trend of the output voltage according to the sampled current.

[0010] In one embodiment, the battery parameters include battery voltage and open-circuit voltage; the conversion module further includes:

[0011] A maximum power point setting module, which is respectively connected to the solar cell layer and the control chip, is configured to provide a power signal to the control chip according to the open-circuit voltage, and the power signal is used to control the control chip to obtain the maximum power point voltage according to the battery parameters;

[0012] Wherein, the control chip is further configured to generate the control signal according to the difference between the battery voltage and the maximum power point voltage.

[0013] In one embodiment, the maximum power point setting module includes:

[0014] A first resistor, one end of which is connected to the solar cell layer;

[0015] A second resistor, one end of which is respectively connected to the other end of the first resistor and the maximum power point tracking setting pin of the control chip, and the other end of the second resistor is connected to the ground terminal;

[0016] A control unit, which is connected to the adjustment terminal of the second resistor, is configured to adjust the resistance value of the second resistor according to the open-circuit voltage.

[0017] In one embodiment, the power conversion module includes:

[0018] A switching circuit, which is respectively connected to the solar cell layer and the control chip, and the control signal is used to control the state of the switching circuit to generate the output voltage according to the battery voltage;

[0019] A target voltage setting circuit, which is respectively connected to the switching circuit and the control chip, is configured to set the target voltage and generate and send a sampled voltage to the control chip according to the output voltage;

[0020] Wherein, the control chip is further configured to generate the control signal according to the sampled voltage.

[0021] In one embodiment, the first end of the switch circuit is connected to the solar cell layer to receive the battery voltage; the second end of the switch circuit is connected to the control chip to receive the control signal; the third end of the switch circuit is connected to the target voltage setting circuit;

[0022] Wherein, the third ends of the switch circuits in multiple conversion modules are connected to a load to provide parallel output voltages corresponding to each solar cell layer to the load.

[0023] In one embodiment, the conversion module further includes:

[0024] A protection circuit, which is respectively connected to the power conversion module and the load, and is used to prevent the reverse output of the output voltage.

[0025] In one embodiment, the control chip is further configured to determine the state of the solar cell layer according to the battery voltage. In response to the battery voltage being greater than or equal to a preset voltage, it is determined that the solar cell layer is in a normal state, and the control chip operates normally.

[0026] In one embodiment, in response to the battery voltage being less than the preset voltage, the control chip determines that the solar cell layer is in an abnormal state, and the control chip enters the sleep mode.

[0027] In one embodiment, the stacked battery structure includes two solar cell layers, which are a perovskite battery layer and a crystalline silicon battery layer respectively, and the target voltages corresponding to the perovskite battery layer and the crystalline silicon battery layer are the same.

[0028] A junction box for a stacked battery structure, the stacked battery structure includes a plurality of solar cell layers with different battery parameters that are stacked and spaced apart, and the junction box includes: the voltage stabilizing device as described above, a plurality of battery terminals and a load terminal;

[0029] Wherein, one ends of the plurality of battery terminals are respectively connected to one ends of the plurality of conversion modules in the voltage stabilizing device in a corresponding manner, and the other ends of the plurality of battery terminals are respectively connected to the plurality of solar cell layers; the other ends of the plurality of conversion modules are respectively connected to one end of the load terminal; the other end of the load terminal is connected to the load.

[0030] A photovoltaic system, comprising:

[0031] A stacked battery structure, including a plurality of solar cell layers with different battery parameters that are stacked and spaced apart;

[0032] The voltage stabilizing device as described above.

[0033] In the above voltage stabilizing device, junction box and photovoltaic system, the conversion modules are connected to the solar cell layers one by one, independently stabilizing the solar cell layers, maintaining the stability of the output voltage, and achieving the regulation of the output voltages of each layer of solar cell layers and the voltage matching between the solar cell layers. The control signals generated by the control chips in the conversion modules are related to the maximum power point voltages of the solar cell layers. While achieving the individual optimization of the solar cell layers, it maximizes the output efficiency and enables efficient energy transmission, reduces energy loss, and improves the efficiency of the stacked cell structure. Moreover, the conversion modules implement the control logic through hardware, without the need for additional software algorithms. The control logic is simple and intuitive, and the response speed is fast. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0035] Figure 1 FIG. 1 is one of the schematic structural diagrams of the voltage stabilizing device in some embodiments of the present application;

[0036] Figure 2 FIG. 2 is another schematic structural diagram of the voltage stabilizing device in some embodiments of the present application;

[0037] Figure 3 FIG. 3 is yet another schematic structural diagram of the voltage stabilizing device in some embodiments of the present application;

[0038] Figure 4 FIG. 4 is still another schematic structural diagram of the voltage stabilizing device in some embodiments of the present application;

[0039] Figure 5 FIG. 5 is the schematic circuit diagram of the voltage stabilizing device in some embodiments.

[0040] DESCRIPTION OF REFERENCE NUMERALS:

[0041] Stacked cell structure 10; conversion module 20; solar cell 102; control chip 104; power conversion module 106; sampling module 108; maximum power point setting module 110; load 112; protection circuit 114; control unit 202; switch circuit 204; target voltage setting circuit 206; target control unit 302. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] To facilitate the understanding of this application, the following will provide a more comprehensive description of this application with reference to the relevant accompanying drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of this application more thorough and comprehensive.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this application herein are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0044] It can be understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first resistor may be referred to as the second resistor, and similarly, the second resistor may be referred to as the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0045] Spatial relationship terms such as "under", "below", "beneath", "underneath", "above", "over", etc. can be used herein to describe the relationship between one element or feature shown in the drawings and other elements or features. It should be understood that in addition to the orientation shown in the drawings, spatial relationship terms also include different orientations of the device during use and operation. For example, if the device in the drawing is flipped, the element or feature described as "under other elements" or "beneath it" or "under it" will be oriented "above" the other elements or features. Therefore, the exemplary terms "under" and "beneath" can include both the upper and lower orientations. In addition, the device may also include other orientations (such as rotating 90 degrees or other orientations), and the spatial description terms used herein are accordingly interpreted.

[0046] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element or connected to the other element through an intermediate element. In addition, in the following embodiments, "connection", if there is a transfer of electrical signals or data between the connected objects, should be understood as "electrical connection", "communication connection", etc.

[0047] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprises / comprising" or "has / including" etc. specify the presence of the stated features, integers, steps, operations, components, parts or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0048] Figure 1 One of the schematic structural diagrams of the voltage stabilizing device in some embodiments of the present application, see Figure 1 , in this embodiment, a voltage stabilizing device is provided. The voltage stabilizing device is connected to the stacked battery structure 10. The stacked battery structure 10 includes a plurality of solar cell layers 102 that are stacked and spaced apart. The plurality of solar cell layers 102 are stacked in a direction perpendicular to the stacked battery structure 10, and are independently arranged between the plurality of solar cell layers 102. The battery parameters of any two solar cell layers 102 are different. It can be understood that the battery parameters include the battery current, battery voltage and open circuit voltage of the solar cell layer 102. The voltage stabilizing device includes: a plurality of conversion modules 20, the plurality of conversion modules 20 are respectively connected to the plurality of solar cell layers 102, and the number of conversion modules 20 is the same as the number of solar cell layers 102.

[0049] The conversion module 20 includes a control chip 104 and a power conversion module 106. The control chip 104 is respectively connected to the corresponding solar cell layer 102 and the power conversion module 106, and is used to obtain the maximum power point voltage V of the solar cell layer 102 according to the battery parameters of the solar cell layer 102 MPPT , and according to the maximum power point voltage V MPPT , the battery parameters of the solar cell layer 102 and the target voltage of the solar cell layer 102, generate a control signal, and send the control signal to the power conversion module 106, wherein the target voltage is the voltage value set for the solar cell layer 102 to provide to the load. As an example, each conversion module 20 has the same structure.

[0050] The power conversion module 106 is connected to the solar cell layer 102. The control signal received by the power conversion module 106 is used to control the power conversion module 106 to generate an output voltage according to the battery parameters of the corresponding solar cell layer 102, and the voltage difference between the output voltage and the target voltage is within a preset range. The preset range is the deviation that can be received between the output voltage and the target voltage, that is, the fluctuation range of the target voltage.

[0051] In the above voltage stabilizing device, the conversion module 20 and the solar cell layer 102 are connected in one-to-one correspondence, independently stabilizing the voltage of the solar cell layer 102, maintaining the stability of the output voltage, and realizing the regulation of the output voltage of each layer of the solar cell layer 102 and the voltage matching between the solar cell layers 102; the control signal generated by the control chip 104 in the conversion module 20 is related to the maximum power point voltage V of the solar cell layer 102. MPPT While realizing the individual optimization of the solar cell layer 102, it maximizes the output efficiency and enables efficient energy transmission, reduces energy loss, and improves the efficiency of the stacked cell structure. Moreover, the conversion module 20 implements the control logic through hardware, without the need for additional software algorithms. The control logic is simple and intuitive, and the response speed is fast.

[0052] Figure 2 FIG. is a second schematic structural diagram of the voltage stabilizing device in some embodiments of the present application. Refer to Figure 2 , in some embodiments, the battery parameters include the battery voltage and the battery current. The conversion module 20 further includes: a sampling module 108; the sampling module 108 is respectively connected to the control chip 104 and the power conversion module 106. The sampling module 108 is used to collect the output current corresponding to the output voltage generated by the power conversion module 106 and generate a sampling current according to the output current; wherein, the control chip 104 is further used to determine the change trend of the output voltage according to the sampling current. The change trend refers to the relative increase or decrease of the output voltage. The control chip 104 can adjust the control signal according to the change trend of the output voltage, thereby dynamically regulating the output voltage and reducing the voltage difference between the output voltage and the target voltage. As an example, the sampling module 108 includes a sampling resistor.

[0053] Refer to Figure 2 , in some embodiments, the battery parameters include the battery voltage and the open circuit voltage; the conversion module 20 further includes: a maximum power point setting module 110; the maximum power point setting module 110 is respectively connected to the solar cell layer 102 and the control chip 104, and is used to provide a power signal to the control chip 104 according to the open circuit voltage. The power signal is used to control the control chip 104 to obtain the maximum power point voltage corresponding to the solar cell layer 102 according to the battery parameters of the solar cell layer 102; wherein, the control chip 104 is further used to generate a control signal according to the difference between the battery voltage and the maximum power point voltage. It can be understood that the battery parameters provided by the solar cell layer 102 change with temperature and light. The maximum power point voltage obtained by the control chip 104 according to the battery parameters of the solar cell layer 102 is the theoretical value of the maximum power point voltage corresponding to the solar cell layer 102, which is less than or equal to the open circuit voltage of the solar cell layer 102. As an example, the ratio between the maximum power point voltage and the open circuit voltage is greater than or equal to 0.7 and less than or equal to 0.9, such as 0.8.

[0054] Figure 3 This is the third schematic diagram of the voltage stabilizing device in some embodiments of the present application. Refer to Figure 3 , in some embodiments, the maximum power point setting module 110 includes: a first resistor R1, a second resistor R2, and a control unit 202; one end of the first resistor R1 is connected to the solar cell layer 102, and one end of the second resistor R2 is respectively connected to the other end of the first resistor R1 and the maximum power point tracking setting pin MPPT of the control chip 104, and the other end of the second resistor R2 is connected to the ground terminal GND. The solar cell layer 102 is connected to the external power input pin VG of the control chip 102; the control unit 202 is connected to the adjustment end of the second resistor R2, and the control unit 202 is configured to adjust the resistance value of the second resistor R2 according to the open-circuit voltage of the solar cell layer 102. By the control unit 202 and the second resistor R2 with variable resistance value, the voltage stabilizing device can be used for solar cell layers 102 with different battery parameters, increasing the application scenarios of the voltage stabilizing device.

[0055] Figure 4 This is the fourth schematic diagram of the voltage stabilizing device in some embodiments of the present application. Refer to Figure 4 , in some embodiments, the power conversion module 106 includes: a switching circuit 204 and a target voltage setting circuit 206.

[0056] The switching circuit 204 is respectively connected to the solar cell layer 102 and the control chip 104. The control signal is used to control the state of the switching circuit 204 to generate an output voltage according to the battery voltage of the solar cell layer 102. The state of the switching circuit 204 includes a conducting state and a non-conducting state; the target voltage setting circuit 206 is respectively connected to the switching circuit 204 and the control chip 104, and is configured to set a target voltage and generate and send a sampling voltage to the control chip 104 according to the output voltage; wherein, the control chip 104 is further configured to generate a control signal according to the sampling voltage. As an example, the switching circuit 204 includes a switching transistor.

[0057] Refer to Figure 4 , in some embodiments, the first end of the switching circuit 204 is connected to the solar cell layer 102 to receive the battery voltage; the second end of the switching circuit 204 is connected to the control chip 104 to receive the control signal; the third end of the switching circuit 204 is connected to the target voltage setting circuit 206; wherein, the third ends of the switching circuits 204 in the plurality of conversion modules 20 are connected to the load 112 to provide parallel output voltages corresponding to the respective solar cell layers 102 to the load 112.

[0058] It can be understood that the first end of the switch circuit 204 is connected to the solar cell layer 102, the second end of the switch circuit 204 is connected to the driving end of the control chip 104 to receive a control signal; the third end of the switch circuit 204 is connected to the sampling module 108; the target voltage setting circuit 206 is connected to the switch circuit 204 through the sampling module 108, so as to generate a sampling voltage according to the output voltage of the switch circuit 204, and the target voltage setting circuit 206 is connected to the voltage feedback pin of the control chip 104 to send the sampling voltage corresponding to the sampling current to the control chip 104.

[0059] See Figure 4 , in some embodiments, the conversion module 20 further includes: a protection circuit 114; the protection circuit 114 is respectively connected to the power conversion module 106 and the load 112, and is used to prevent the reverse output of the output voltage. As an example, the protection circuit 114 includes a diode, the positive pole of the diode is connected to the power conversion module 106, and the negative pole of the diode is connected to the load 112. It can be understood that the power conversion module 106 includes a switch circuit 204 and a target voltage setting circuit 206, and the protection circuit 114 is respectively connected to the switch circuit 204 and the target voltage setting circuit 206. Through the protection circuit 114, reverse injection of the output voltage can be avoided and energy loss can be reduced.

[0060] In some embodiments, the control chip 104 is further configured to determine the state of the solar cell layer 102 according to the battery voltage of the solar cell layer 102. In response to the battery voltage being greater than or equal to a preset voltage, it is determined that the solar cell layer 102 is in a normal state, and the control chip 104 operates normally. The normal state means that the solar cell layer 102 can normally provide an output voltage to the load 112.

[0061] In some embodiments, in response to the battery voltage being less than the preset voltage, the control chip 104 determines that the solar cell layer 102 is in an abnormal state, and the control chip 104 enters the sleep mode. The abnormal state means that the voltage of the solar cell layer 102 is less than the preset value, including too low voltage or power-off of the solar cell layer 102.

[0062] In some embodiments, the stacked battery structure 10 includes two solar cell layers 102, the two solar cell layers 102 are a perovskite battery layer and a crystalline silicon battery layer respectively, and the target voltages corresponding to the perovskite battery layer and the crystalline silicon battery layer are the same. Through a voltage stabilizing device, voltage matching between solar cell layers 102 with different battery currents and battery voltages is achieved.

[0063] Figure 5 For the circuit schematic diagram of the voltage stabilizing device in some embodiments, see Figure 5, in one embodiment, the switching circuit 204 includes a switching transistor Q1, and the target voltage setting circuit 206 includes a third resistor R3, a fourth resistor R4, and a target control unit 302; the source and drain terminals of the switching transistor Q1 are the first terminal and the third terminal respectively, and the control terminal of the switching transistor Q1 is the second terminal; one end of the third resistor R3 is connected to the switching circuit 204, and the other end of the third resistor R3 is respectively connected to one end of the fourth resistor R4 and the voltage feedback pin FB of the control chip 104, and the other end of the fourth resistor R4 is connected to the ground terminal GND; the target control unit 302 is connected to the adjustment terminal of the fourth resistor R4, and the target control unit 302 is used to adjust the resistance value of the fourth resistor R4 to achieve the purpose of setting the target voltage. Through the target control unit 302 and the fourth resistor R4 with variable resistance value, the target voltage corresponding to the solar cell layer 102 can be adjusted, increasing the application scenarios of the voltage stabilizing device. As an example, the switching transistor Q1 is a switching transistor TPCA8103.

[0064] See Figure 5 , the control chip 104 is a CN3795 chip U1, and the sampling module 108 is located between the switching circuit 204 and the target voltage setting circuit 206. The sampling module 108 includes resistors R5, R6, and R7 connected in series. The common terminal of the resistor R5 and the resistor R6 is connected to the switching circuit 204, the other end of the resistor R6 is connected to the current sampling pin CSP of the control chip 104, the common terminal of the resistor R5 and the resistor R7 is connected to the target voltage setting circuit 206, and the other end of the resistor R7 is connected to the battery connection pin BAT of the control chip 104. As an example, the resistance values of the resistor R6 and the resistor R7 are the same, for example, 100 ohms. Further, the control chip 104 is a high-voltage chip, so that the voltage stabilizing device can match the solar cell layer 102 with a larger battery voltage range. As an example, in the stacked battery structure 102, the battery voltage of the solar cell layer 102 is greater than or equal to 6.6 volts and less than or equal to 30 volts, including a crystalline silicon solar cell layer with a battery voltage of 12 volts and a crystalline silicon solar cell layer with a battery voltage of 24 volts.

[0065] It can be understood that the conversion module 20 further includes a Schottky diode D1, an inductor L1, a capacitor C1, and a capacitor C2. The Schottky diode D1 prevents loop fluctuations, the inductor L1 plays a role in current limiting, and the capacitors C1 and C2 play a role in filtering. As an example, the inductor L1 is 20 uH; the capacitor C1 is 220 uF, and the capacitor C2 is 1 uF, 50V.

[0066] See Figure 5, the conversion module 20 further includes a power module 208. The power module 208 is connected to the power input pin VCC of the control chip 104 and is used to provide operating power to the control chip 104 so that the control chip 104 can operate normally. As an example, the power module 208 is a power supply with a fixed voltage. Further, the power module 208 includes a resistor R8 and a capacitor C3. One end of the resistor R8 is connected to the solar cell layer 102, the other end of the resistor R8 is respectively connected to one end of the capacitor C3 and the power input pin VCC of the control chip 104, and the other end of the capacitor C3 is connected to the ground terminal. The power module 208 is used to generate and provide an operating voltage to the control chip 104 according to the battery voltage V1. As an example, the capacitor C3 is 10uf, 50V; the resistor R8 is 5.1 ohms.

[0067] See Figure 5 , the conversion module 20 further includes a battery switch Q2, a resistor R9, a varistor D2, capacitors C4, C5 and C6. The battery switch Q2 is a switching transistor TPCA8103, which is used to control the connection or disconnection of the solar cell layer 102 to ensure the current flow direction; the capacitors C4, C5 and C6 play a filtering role. As an example, the resistor R9 is 22KΩ, the capacitor C4 is 220uF, the capacitor C5 is 1uF, 50V, and the capacitor C6 is 100nF, 50V.

[0068] Further, the conversion module 20 further includes a series-connected resistor R10 and a light-emitting diode D3. One end of the resistor R10 is connected to the solar cell layer 102, and the light-emitting diode D3 is connected to the charging status indication pin nCHRG of the control chip 104. As an example, the resistor R10 is 33KΩ.

[0069] In addition, the conversion module 20 further includes a capacitor C7. The capacitor C7 is connected between the solar cell layer 102 and the external power input pin VG of the control chip 104, and the capacitor C7 plays a voltage stabilizing role; the protection circuit 114 includes a diode D4. As an example, the capacitor C7 is 100nF.

[0070] Based on the same inventive concept, the present disclosure provides a junction box for a laminated battery structure 10. The laminated battery structure 10 includes a plurality of solar cell layers 102 with different battery parameters that are stacked and spaced apart. The junction box includes: the voltage stabilizing device as described above, a plurality of battery connection terminals and a load connection terminal; wherein, one ends of the plurality of battery connection terminals are respectively connected to one ends of the plurality of conversion modules in the voltage stabilizing device, and the other ends of the plurality of battery connection terminals are respectively connected to the plurality of solar cell layers; the other ends of the plurality of conversion modules are respectively connected to one end of the load connection terminal; the other end of the load connection terminal is connected to the load.

[0071] Based on the same inventive concept, the present disclosure also provides a photovoltaic system, comprising: a stacked cell structure 10 and the voltage stabilizing device as described above; the stacked cell structure 10 includes a plurality of solar cell layers 102 with different cell parameters that are stacked and spaced apart.

[0072] In the description of the present specification, the description with reference to terms such as "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or features described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In the present specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0073] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0074] The above-described embodiments merely represent several implementation manners of the present application, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A voltage stabilizing device for connecting to a stacked battery structure, the stacked battery structure comprising a plurality of solar cell layers stacked and spaced apart, characterized in that, The voltage stabilizing device includes: Multiple conversion modules, respectively connected to the multiple solar cell layers correspondingly; the conversion module includes: A control chip and a power conversion module; the control chip is respectively connected to the solar cell layer and the power conversion module, and the power conversion module is connected to the solar cell layer; Wherein, the control chip is used to obtain the maximum power point voltage of the solar cell layer according to the battery parameters of the solar cell layer, and generate a control signal according to the maximum power point voltage, the battery parameters and the target voltage corresponding to the solar cell layer. The battery parameters of any two solar cell layers are different; the control signal is used to control the power conversion module to generate an output voltage according to the battery parameters, and the voltage difference between the output voltage and the target voltage is within a preset range.

2. The voltage stabilizing device according to claim 1, characterized in that, The battery parameters include battery voltage and battery current, and the conversion module further includes: A sampling unit, respectively connected to the control chip and the power conversion module, for collecting the output current of the power conversion module and generating a sampling current; wherein, the control chip is further used to determine the change trend of the output voltage according to the sampling current.

3. The voltage stabilizing device according to claim 1, characterized in that, The battery parameters include battery voltage and open circuit voltage; the conversion module further includes: A maximum power point setting module, respectively connected to the solar cell layer and the control chip, for providing a power signal to the control chip according to the open circuit voltage, and the power signal is used to control the control chip to obtain the maximum power point voltage according to the battery parameters; Wherein, the control chip is further used to generate the control signal according to the difference between the battery voltage and the maximum power point voltage.

4. The voltage stabilizing device according to claim 3, wherein The maximum power point setting module includes: A first resistor, one end of the first resistor is connected to the solar cell layer; A second resistor, one end of the second resistor is respectively connected to the other end of the first resistor and the maximum power point tracking setting pin of the control chip, and the other end of the second resistor is connected to the ground terminal; A control unit, connected to the adjustment end of the second resistor, for adjusting the resistance value of the second resistor according to the open circuit voltage.

5. The voltage stabilizing device according to claim 3, characterized in that, The power conversion module includes: A switching circuit, respectively connected to the solar cell layer and the control chip, and the control signal is used to control the state of the switching circuit to generate the output voltage according to the battery voltage; A target voltage setting circuit, respectively connected to the switching circuit and the control chip, for setting the target voltage and generating and sending a sampling voltage to the control chip according to the output voltage; Wherein, the control chip is further used to generate the control signal according to the sampling voltage.

6. The voltage stabilizing device according to claim 5, characterized in that The first end of the switching circuit is connected to the solar cell layer to receive the battery voltage; the second end of the switching circuit is connected to the control chip to receive the control signal; the third end of the switching circuit is connected to the target voltage setting circuit; Among them, the third terminal of the switch circuit in multiple conversion modules is connected to the load to provide parallel output voltages corresponding to each of the solar cell layers to the load.

7. The voltage stabilizing device according to claim 6, characterized in that, The conversion module further includes: A protection circuit, respectively connected to the power conversion module and the load, for preventing reverse output of the output voltage.

8. The voltage stabilizing device according to claim 1, wherein The control chip is further configured to determine the state of the solar cell layer according to the battery voltage. In response to the battery voltage being greater than or equal to a preset voltage, it is determined that the solar cell layer is in a normal state, and the control chip operates normally.

9. The voltage stabilizing device according to claim 8, characterized in that, In response to the battery voltage being less than the preset voltage, the control chip determines that the solar cell layer is in an abnormal state, and the control chip enters the sleep mode.

10. The voltage stabilizing device according to claim 1, characterized in that, The stacked battery structure includes two solar cell layers, which are a perovskite battery layer and a crystalline silicon battery layer respectively, and the target voltages corresponding to the perovskite battery layer and the crystalline silicon battery layer are the same.

11. A junction box for a stacked battery structure, the stacked battery structure comprising a plurality of solar cell layers with different battery parameters that are stacked and spaced apart, characterized in that, It includes: The voltage stabilizing device according to any one of claims 1-10, a plurality of battery connection terminals, and a load connection terminal; Among them, one ends of the plurality of battery connection terminals are respectively and correspondingly connected to one ends of the plurality of conversion modules in the voltage stabilizing device, and the other ends of the plurality of battery connection terminals are respectively and correspondingly connected to the plurality of solar cell layers; The other ends of the plurality of conversion modules are respectively connected to one end of the load connection terminal; the other end of the load connection terminal is connected to the load.

12. A photovoltaic system, characterized in that, It includes: A stacked battery structure, including a plurality of solar cell layers with different battery parameters that are stacked and spaced apart; The voltage stabilizing device according to any one of claims 1-10.

Images