Photovoltaic power supply circuit and photovoltaic system

Abstract

This utility model provides a photovoltaic power supply circuit and a photovoltaic system, relating to the field of photovoltaic energy storage technology. In this utility model, the photovoltaic power supply circuit includes a detection module, a maximum power point tracking (MPPT) module, a channel switching module, and an energy storage module connected in sequence. The detection module detects the supply voltage output by the photovoltaic power generation circuit to obtain a voltage detection signal. The MPPT module outputs a first charging voltage based on a first supply voltage or a second charging voltage based on a second supply voltage. The channel switching module includes at least a first channel and a second channel, and is used to switch the first channel based on the first charging voltage or the second channel based on the second charging voltage, so that the channel switching module is connected to the MPPT module and the energy storage module respectively. The energy storage module is used to access the target charging voltage through the first channel or the second channel. Therefore, this reduces circuit costs and minimizes the waste of circuit resources.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic energy storage technology, and in particular to a photovoltaic power supply circuit and a photovoltaic system. Background Technology

[0002] Maximum power point tracking (MPPT) modules (or MPPT controllers) are devices used for photovoltaic power generation. Through MPPT technology, the output voltage or output current of the photovoltaic power generation circuit is adjusted in real time to keep it at the maximum power point, thereby improving the power generation efficiency of the photovoltaic power generation circuit.

[0003] In existing photovoltaic systems, see Figure 1 As shown, to adapt to different outputs of the photovoltaic power generation circuit C1 (e.g., high voltage output V), H Or low-voltage output V L Adaptive design of photovoltaic power supply circuits will increase circuit costs. Utility Model Content

[0004] This utility model provides a photovoltaic power supply circuit and photovoltaic system to reduce circuit costs and reduce waste of circuit resources.

[0005] In a first aspect, embodiments of the present invention provide a photovoltaic power supply circuit electrically connected to a photovoltaic power generation circuit for outputting a power supply voltage. The photovoltaic power supply circuit includes: a detection module, a maximum power point tracking module, a channel switching module, and an energy storage module, connected in sequence.

[0006] The detection module is used to detect the power supply voltage and obtain a voltage detection signal; the voltage detection signal is used to indicate that the power supply voltage is a first power supply voltage or a second power supply voltage, wherein the first power supply voltage is greater than the second power supply voltage.

[0007] The maximum power point tracking module is used to output a first charging voltage based on the first supply voltage, or to output a second charging voltage based on the second supply voltage;

[0008] The channel switching module includes at least a first channel and a second channel. The channel switching module is used to switch the first channel based on the first charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively, or to switch the second channel based on the second charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively; the first channel is used to output a target charging voltage according to the first charging voltage, and the second channel is used to output the target charging voltage according to the second charging voltage;

[0009] The energy storage module is used to access the target charging voltage through the first channel or the second channel.

[0010] Secondly, this utility model embodiment provides a photovoltaic system, the photovoltaic system comprising:

[0011] A photovoltaic power generation circuit and a photovoltaic power supply circuit as described in the first aspect, wherein the output terminal of the photovoltaic power generation circuit is electrically connected to the input terminal of the photovoltaic power supply circuit; wherein,

[0012] The photovoltaic power generation circuit includes: a plurality of photovoltaic modules arranged in an array, the plurality of photovoltaic modules being used to output the power supply voltage of the photovoltaic power supply circuit; the power supply voltage is a first power supply voltage or a second power supply voltage, wherein the first power supply voltage is greater than the second power supply voltage.

[0013] The beneficial effects of this utility model are as follows:

[0014] In the photovoltaic power supply circuit provided in this embodiment of the invention, a detection module can detect the supply voltage generated and output by the photovoltaic power generation circuit, and obtain a voltage detection signal to indicate the type of supply voltage. For example, the voltage detection signal can indicate whether the supply voltage is a first supply voltage or a second supply voltage. Furthermore, a maximum power point tracking (MPPT) module outputs a first charging voltage corresponding to the first supply voltage or a second charging voltage corresponding to the second supply voltage, based on the type of supply voltage indicated by the voltage detection signal (i.e., the first supply voltage or the second supply voltage). Additionally, a channel switching module can switch between a first channel for outputting a target charging voltage based on the first charging voltage or a second channel for outputting a target charging voltage based on the second charging voltage, based on the first charging voltage or the second charging voltage. In this way, the energy storage module can access the target charging voltage through the first channel or the second channel to achieve energy storage. Therefore, only one MPPT module is needed to achieve energy storage of the energy storage module under different supply voltages, reducing the circuit cost caused by needing different MPPT modules for different supply voltages. Furthermore, it improves the problem of wasted circuit resources due to the existence of idle MPPT modules in related technologies.

[0015] Furthermore, other features and advantages of this invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described herein are used to provide a further understanding of this utility model, constitute a part of this utility model, and do not constitute an improper limitation of this utility model. In the accompanying drawings:

[0017] Figure 1 A schematic diagram of the system architecture of a related photovoltaic system is provided for an embodiment of this utility model;

[0018] Figure 2 A schematic diagram of the composition structure of a photovoltaic power supply circuit provided for an embodiment of this utility model;

[0019] Figure 3 A schematic diagram of the composition structure of another photovoltaic power supply circuit provided in an embodiment of this utility model;

[0020] Figure 4 A schematic diagram of the composition structure of another photovoltaic power supply circuit provided in this embodiment of the utility model;

[0021] Figure 5 A schematic diagram of the composition structure of another photovoltaic power supply circuit provided in an embodiment of this utility model;

[0022] Figure 6 A schematic diagram of an H-bridge circuit provided in an embodiment of this utility model;

[0023] Figure 7 This is a schematic diagram of an optional photovoltaic system architecture provided for an embodiment of the present utility model.

[0024] Reference numerals: 1 - Photovoltaic power supply circuit; 11 - Detection module; 12 - Maximum power point tracking module; 121 - Third conversion unit; 122 - Control unit; 13 - Channel switching module; 131 - First channel; 1311 - First conversion unit; 13111 - Inductor-inductor-capacitor (LLC) resonant circuit; 1312 - Busbar; 132 - Second channel; 1321 - Second conversion unit; 1322 - Conductor line; 133 - Switching unit; 14 - Energy storage module; 2 - Photovoltaic power generation circuit. Detailed Implementation

[0025] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings. Throughout the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0026] To enable those skilled in the art to better understand the solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0027] In this embodiment of the present invention, it should be noted that relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0028] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0029] In the description of the embodiments of this utility model, the words "example" or "for example" are used to indicate illustration, explanation, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this utility model is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0030] Furthermore, in the embodiments of this utility model, "multiple" refers to two or more. Therefore, in the embodiments of this utility model, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, for example, one, two, or more. For example, including at least one means including one, two, or more, and it does not limit which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.

[0031] It should be noted that in this embodiment of the invention, "and / or" describes the relationship between the associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following associated objects have an "or" relationship. It should be pointed out that in this embodiment of the invention, "connection" can be understood as an electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0032] In the circuit structure provided by the embodiments of this utility model, nodes such as the first node and the second node do not represent actual existing components, but rather represent the junction points of related couplings in the circuit diagram. That is, these nodes are equivalent to the junction points of related couplings in the circuit diagram. Furthermore, the names of the messages or information exchanged between multiple devices in the embodiments of this utility model are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0033] The design concept of this utility model embodiment is briefly introduced below:

[0034] Maximum power point tracking (MPPT) modules (such as MPT solar charge controllers) can efficiently transfer the electrical energy generated by photovoltaic power generation circuits to energy storage modules (such as batteries) to meet the power supply needs of various power supply scenarios.

[0035] In existing photovoltaic systems, the number and combination of photovoltaic units (e.g., photovoltaic panels) used to convert light energy (e.g., solar energy) into electrical energy may vary in different photovoltaic power generation circuits. Therefore, the voltage output of photovoltaic power generation circuits can be divided into different types of output, such as high-voltage output or low-voltage output.

[0036] Wherein, the voltage value corresponding to the high voltage output is greater than the preset output voltage set for the photovoltaic power generation circuit, and the voltage value corresponding to the low voltage output is less than or equal to the preset output voltage.

[0037] And, as Figure 1As shown, to accommodate different outputs of the photovoltaic (PV) power generation circuit C1 (e.g., high-voltage output VH or low-voltage output VL), maximum power point tracking (MPPT) modules are typically set up in both the PV power generation circuit and the energy storage module (M1) for different outputs. Specifically, a high-voltage MPT module (M2) is set up for the high-voltage output, and a low-voltage MPT module (M3) is set up for the low-voltage output. However, in the aforementioned PV system, the need to set up different MPT modules for different outputs of the PV power generation circuit leads to higher circuit costs. Furthermore, in most operating scenarios, only one MPT module is active, while the others remain idle, resulting in a waste of circuit resources.

[0038] In view of this, in order to solve or improve the above problems, this utility model provides a photovoltaic power supply circuit, see reference. Figure 2 As shown, the photovoltaic power supply circuit 1 may include: a detection module 11, a maximum power point tracking module 12, a channel switching module 13, and an energy storage module 14. The detection module 11 is electrically connected to both the photovoltaic power generation circuit 2 and the maximum power point tracking module 12, and the channel switching module 13 is electrically connected to both the maximum power point tracking module 12 and the energy storage module 14. In other words, the detection module 11, the maximum power point tracking module 12, the channel switching module 13, and the energy storage module 14 are electrically connected sequentially.

[0039] The detection module 11 can be used to detect the supply voltage generated and output by the photovoltaic power generation circuit 2, and obtain a voltage detection signal Signal.Vd. The voltage detection signal can be used to indicate whether the aforementioned supply voltage is a first supply voltage or a second supply voltage, wherein the first supply voltage is greater than the second supply voltage. For example, the aforementioned supply voltage can be denoted as: V IN The aforementioned first supply voltage can be denoted as: V S1 The aforementioned second supply voltage can be denoted as: V S2 .

[0040] In one optional implementation, the first supply voltage is greater than a preset supply voltage, and the second supply voltage is less than or equal to the preset supply voltage (which can be denoted as: V). STH The aforementioned preset supply voltage is used to distinguish whether the supply voltage generated and output by the photovoltaic power generation circuit 2 is high voltage or low voltage. Therefore, the aforementioned first supply voltage can be called high voltage supply voltage, and the aforementioned second supply voltage can be called low voltage supply voltage. Of course, the aforementioned first supply voltage and the aforementioned second supply voltage can also have other names, and this embodiment of the utility model does not specifically limit them.

[0041] Taking the aforementioned preset supply voltage of 60 volts (V) as an example, assuming that the supply voltage generated and output by photovoltaic power generation circuit 2 is 40V, it can be seen that the supply voltage generated and output by photovoltaic power generation circuit 2 (i.e., 40V) is less than the aforementioned preset supply voltage (i.e., 60V). Therefore, it can be determined that the supply voltage generated and output by photovoltaic power generation circuit 2 (i.e., 40V) is the second supply voltage. As another example, assuming that the supply voltage generated and output by photovoltaic power generation circuit 2 is 100V, it can be seen that the supply voltage generated and output by photovoltaic power generation circuit 2 (i.e., 100V) is greater than the aforementioned preset supply voltage (i.e., 60V). Therefore, it can be determined that the supply voltage generated and output by photovoltaic power generation circuit 2 (i.e., 100V) is the first supply voltage.

[0042] The aforementioned preset supply voltage can be set for the voltage output range of the photovoltaic power supply circuit 1. Optionally, the aforementioned preset supply voltage can be the intermediate voltage value of the voltage output range of the photovoltaic power supply circuit 1. For example, taking the voltage output range of the photovoltaic power supply circuit 1 as [30V, 90V], the intermediate voltage value of the aforementioned voltage output range can be determined to be (30+90) / 2 = 60V, and thus the aforementioned preset supply voltage can be determined to be 60V.

[0043] Furthermore, the aforementioned preset power supply voltage may include multiple preset voltages, so the aforementioned first power supply voltage and the aforementioned power supply voltage input may also be further divided into multiple power supply voltages, and this embodiment of the present invention does not limit this.

[0044] The maximum power point tracking module 12 can be used to output a first charging voltage based on a first supply voltage, or to output a second charging voltage based on a second supply voltage. That is, when the voltage detection signal indicates that the supply voltage is the first supply voltage, the maximum power point tracking module 12 can output the first charging voltage based on the first supply voltage, and when the voltage detection signal indicates that the supply voltage is the second supply voltage, it can output the second charging voltage based on the second supply voltage. For example, the aforementioned first charging voltage can be denoted as: V C1 The aforementioned second charging voltage can be denoted as: V C2 .

[0045] Still Figure 2As shown, the channel switching module 13 may include at least a first channel 131 and a second channel 132. The channel switching module 13 can be used to switch the first channel 131 based on a first charging voltage so that the channel switching module 13 is connected to the maximum power point tracking module 12 and the energy storage module 14 respectively; or, the channel switching module 13 can be used to switch the second channel 132 based on a second charging voltage so that the channel switching module 13 is connected to the maximum power point tracking module 12 and the energy storage module 14 respectively. The first channel 131 can be used to output a target charging voltage (which can be denoted as V) according to the first charging voltage. TAC The second channel 132 can be used to output a target charging voltage based on the second charging voltage.

[0046] Therefore, the channel switching module 13 can be used to select and connect the first channel 131 when the target channel corresponding to the target charging voltage is determined to be the first channel 131 based on the voltage detection signal. That is, the channel switching module 13 can be used to select and connect the first channel 131 when the first charging voltage is applied, so that the output terminal of the maximum power point tracking module 12 is connected to the first input terminal of the energy storage module 14 through the first channel 131. Furthermore, the channel switching module 13 can be used to select and connect the second channel 132 when the target channel corresponding to the target charging voltage is determined to be the second channel 132 based on the voltage detection signal. That is, the channel switching module 13 can be used to select and connect the second channel 132 when the second charging voltage is applied, so that the output terminal of the maximum power point tracking module 12 is connected to the second input terminal of the energy storage module 14 through the second channel 132.

[0047] It should be understood that the first channel 131 is a channel designed for the first power supply voltage and can be referred to as the high-voltage power supply transmission channel, while the second channel 132 is a channel designed for the second power supply voltage and can be referred to as the low-voltage power supply transmission channel.

[0048] In this way, energy storage processing for different supply voltages can be achieved using only the maximum power point tracking module 12 and the channel switching module 13, reducing the circuit cost caused by the need to set different maximum power point tracking modules 12 for different supply voltages in related technologies, and reducing the circuit complexity of the entire photovoltaic power supply circuit.

[0049] The energy storage module 14 can be used to access a target charging voltage through a first channel or a second channel. For example, the energy storage module 14 can be a battery, or other types of batteries or energy storage devices; this embodiment of the invention does not limit this. Thus, after accessing the target charging voltage, the energy storage module 14 can store electrical energy based on that target charging voltage.

[0050] based on Figure 2The photovoltaic power supply circuit 1 shown, equipped with output channel selection capability, can detect the supply voltage generated and output by the photovoltaic power generation circuit 2 through the detection module 11, and obtain a voltage detection signal indicating the type of supply voltage, such as whether the supply voltage is a first supply voltage or a second supply voltage. Furthermore, the maximum power point tracking module 12 outputs a first charging voltage corresponding to the first supply voltage or a second charging voltage corresponding to the second supply voltage based on the type of supply voltage indicated by the voltage detection signal (i.e., the first supply voltage or the second supply voltage). Moreover, the channel switching module 13 can switch between a first channel 131 for outputting a target charging voltage based on the first charging voltage or a second channel 132 for outputting a target charging voltage based on the second charging voltage, based on the first charging voltage or the second charging voltage. Thus, the energy storage module 14 can access the target charging voltage through either the first channel 131 or the second channel 132 to achieve energy storage. Therefore, it can be seen that the energy storage of the energy storage module 14 under different supply voltages can be achieved by only the detection module 11, the maximum power point tracking module 12 and the channel switching module 13. This reduces the circuit cost caused by the need to set different maximum power point tracking modules 12 for different supply voltages. Furthermore, it improves the problem of wasted circuit resources caused by the existence of idle maximum power point tracking modules 12 in related technologies.

[0051] In one alternative implementation, see [link to relevant documentation]. Figure 3 As shown, the channel switching module 13 may further include a switching unit 133, that is, the channel switching module 13 may include a first channel 131, a second channel 132, and a switching unit 133. The first channel 131 may include a first conversion unit 1311, the second channel 132 may include a second conversion unit 1321, one end of the switching unit 133 is connected to the maximum power point tracking module 12, and the other end of the switching unit 133 is used to connect to either the first conversion unit 1311 or the second conversion unit 1321. The first input terminal of the energy storage module 14 is electrically connected to the output terminal of the first conversion unit 1311, and the second input terminal of the energy storage module 14 is electrically connected to the output terminal of the second conversion unit 1321.

[0052] The first conversion unit 1311 can be used to perform voltage conversion processing on the first charging voltage and output the target charging voltage. The second conversion unit 1321 can be used to perform voltage conversion processing on the second charging voltage and output the target charging voltage.

[0053] It is understood that the voltage transformation process described above can be either a boost process or a buck process. That is, if the first charging voltage (or the second charging voltage) is less than the target charging voltage, the first charging voltage (or the second charging voltage) is boosted; conversely, if the second charging voltage (or the second charging voltage) is greater than the target charging voltage, the first charging voltage (or the second charging voltage) is bucked.

[0054] In one alternative implementation, if the first charging voltage is greater than the target charging voltage and the second charging voltage is equal to the target charging voltage, then refer to... Figure 4 As shown, the channel switching module 13 may include a first channel 131, a second channel 132, and a switching unit 133. The first channel 131 may include a first conversion unit 1311, and the second channel 132 may include a conductor line 1322. One end of the switching unit 133 is connected to the maximum power point tracking module 12, and the other end of the switching unit 133 is used to connect to either the first conversion unit 1311 or the conductor line 1322. The first input terminal of the energy storage module 14 is electrically connected to the output terminal of the first conversion unit 1311, and the second input terminal of the energy storage module 14 is electrically connected to the conductor line 1322.

[0055] At this time, the first conversion unit 1311 can be used to step down the first charging voltage and output the target charging voltage.

[0056] Optionally, the switching unit 133 can be an analog switch such as a single-pole double-throw switch. Of course, the switching unit 133 can also be a digital switch with 0 / 1 output. For example, when the output of the switching unit 133 is 0, the switching unit 133 selects and connects the first channel 131. When the output of the switching unit 133 is 1, the switching unit 133 selects and connects the second channel 132.

[0057] In one alternative implementation, the first conversion unit 1311 may include an LLC resonant circuit 13111. Using this method, it is unnecessary to include an LLC resonant circuit in the maximum power point tracking module 12. The regulated DC output of the first conversion unit 1311 and the electrical isolation between its input and output can be achieved by reusing the LLC resonant circuit included in the first conversion unit 1311, reducing the circuit complexity of the maximum power point tracking module 12 and saving circuit costs.

[0058] It is understood that the LLC resonant circuit included in the first conversion unit 1311 can be a circuit composed of a resonant inductor Lr, a magnetizing inductor Lm, and a resonant capacitor Cr. Furthermore, by designing or adjusting the resonant inductor Lr, the magnetizing inductor Lm, and the resonant capacitor Cr, phase matching of the resonant current can be ensured, thereby achieving zero voltage switching (ZVS) or zero current switching (ZCS), thus reducing switching losses and improving efficiency.

[0059] To ensure that the output voltage of the maximum power point tracking module 12 can better match the input voltage of the LLC resonant circuit 13111, in one optional implementation, a bus 1312 is provided between the maximum power point tracking module 12 and the LLC resonant circuit 13111. In this case, the first charging voltage output by the maximum power point tracking module 12 can be determined based on the bus voltage. For example, if the bus voltage is 395V, the first charging voltage can be determined to be 395V. Optionally, if the bus voltage is a voltage transmission range, the first charging voltage can be the midpoint of the voltage transmission range of the bus 1312.

[0060] Taking the voltage transmission range of bus 1312 as [390V, 410V] as an example, the intermediate voltage value of the aforementioned voltage transmission range of bus 1312 can be determined to be (390+410) / 2 = 400V, and thus the first charging voltage can be determined to be 400V.

[0061] In other words, when the power supply voltage received by the maximum power point tracking module 12 is the first power supply voltage, the maximum power point tracking module 12 can perform boosting processing on the first power supply voltage received by the maximum power point tracking module 12 according to the first charging voltage determined by the bus voltage, thereby obtaining the first charging voltage.

[0062] In one alternative implementation, the second charging voltage of the maximum power point tracking module 12 may be determined based on the transmission voltage of the conductor line 1322.

[0063] It should be understood that since the wire line 1322 can be used to connect the maximum power point tracking module 12 and the energy storage module 14, the transmission voltage of the wire line 1322 can be the charging voltage of the energy storage module 14, that is, the second charging voltage.

[0064] Therefore, by using the channel switching module 13 to select the power transmission channel (i.e., the first channel 131 or the second channel 132) between the maximum power point tracking module 12 and the energy storage module 14 for different supply voltages, the energy storage module 14 can store energy for different supply voltages using only the maximum power point tracking module 12, thereby reducing circuit costs. Furthermore, during the energy storage process based on the supply voltage generated and output by the photovoltaic power supply circuit 2 in this embodiment, the maximum power point tracking module 12 is always in operation, avoiding the waste of circuit resources caused by the idle maximum power point tracking module 12 in related technologies.

[0065] In one alternative implementation, if the bus voltage is greater than the first supply voltage, then refer to... Figure 5 As shown, the maximum power point tracking module 12 may include a third conversion unit 121. The input terminal of the third conversion unit 121 is connected to the detection module 11, and the output terminal of the third conversion unit 121 is electrically connected to the bus 1312.

[0066] The third conversion unit 121 can be used to boost the first supply voltage when the voltage detection signal indicates that the supply voltage generated and output by the photovoltaic power generation circuit 2 is the first supply voltage, and output the first charging voltage corresponding to the first channel 131. Taking the supply voltage generated and output by the photovoltaic power generation circuit 2 as 100V (i.e., the first supply voltage) as an example, the third conversion unit 121 can boost the 100V supply voltage input to output the first charging voltage corresponding to the first channel 131. For example, the first charging voltage corresponding to the first channel 131 is 400V.

[0067] Furthermore, the third conversion unit 121 can be used to perform voltage conversion processing (e.g., boost processing or buck processing) on ​​the second power supply voltage when the voltage detection signal indicates that the power supply voltage generated and output by the photovoltaic power generation circuit 2 is the second power supply voltage, and output the second charging voltage corresponding to the second channel 132. The second charging voltage can be less than the first charging voltage. Optionally, the second charging voltage can be the charging voltage of the energy storage module 14.

[0068] Assuming the charging voltage of the energy storage module 14 is 50V, and taking the power supply voltage generated and output by the photovoltaic power generation circuit 2 as 40V (i.e., the second power supply voltage) as an example, the third conversion unit 121 can boost the 40V power supply voltage based on the 40V power supply voltage and the 50V charging voltage, outputting a 50V output voltage, thus using the 50V output voltage as the second charging voltage corresponding to the second channel 132. As another example, taking the power supply voltage generated and output by the photovoltaic power generation circuit 2 as 60V (i.e., the second power supply voltage), the third conversion unit 121 can step down the 60V power supply voltage based on the 60V power supply voltage and the 50V charging voltage, outputting a 50V output voltage, thus using the 50V output voltage as the second charging voltage corresponding to the second channel 132.

[0069] For example, when the third conversion unit 121 performs boost or buck processing on the supply voltage, the corresponding circuit can be a Boost circuit, that is, a DC-DC converter.

[0070] In one alternative implementation, it is still as follows Figure 5 As shown, the maximum power point tracking module 12 may further include a control unit 122. The control unit 122 is electrically connected to the third conversion unit 121, the channel switching module 13, and the detection module 11. The control unit 122 can generate a first switching signal, Signal.C.1, when the voltage detection signal indicates that the supply voltage generated and output by the photovoltaic power generation circuit 2 is a first supply voltage. The first switching signal can be used to instruct the channel switching module 13 to switch the output channel of the target charging voltage to the first channel 131 and to control the third conversion unit 121 to boost the first supply voltage to the first charging voltage. Alternatively, the control unit 122 can generate a second switching signal, Signal.C.2, when the voltage detection signal indicates that the supply voltage generated and output by the photovoltaic power generation circuit 2 is a second supply voltage. The second switching signal can be used to instruct the channel switching module 13 to switch the output channel of the target charging voltage to the second channel 132 and to control the third conversion unit 121 to convert the second supply voltage to the second charging voltage.

[0071] Therefore, after receiving the voltage detection signal indicating the type of power supply voltage, the control unit 122 can select the power transmission channel (i.e., the first channel 131 and the second channel 132) between the maximum power point tracking module 12 and the energy storage module 14 according to the indication of the voltage detection signal (i.e., whether the power supply voltage generated and output by the photovoltaic power generation circuit 2 is the first power supply voltage or the second power supply voltage). Thus, the energy storage of the energy storage module 14 under different power supply voltages can be achieved through the first channel 131 or the second channel 132 for power transmission between the maximum power point tracking module 12 and the energy storage module 14.

[0072] In one optional implementation, the third conversion unit 121 may include an H-bridge circuit composed of a first switch, a second switch, a third switch, a fourth switch, and an inductor. The first, second, third, and fourth switches are located in the first, second, third, and fourth arms of the H-bridge circuit, respectively. One end of the inductor is connected to a first node between the first and second switches, and the other end of the inductor is connected to a second node between the third and fourth switches. It should be noted that the first arm can be referred to as the upper left arm, the second arm as the lower left arm, the third arm as the upper right arm, and the fourth arm as the lower right arm.

[0073] At this time, the control unit 122 can also be used to generate a voltage generation signal based on the voltage detection signal. The aforementioned voltage generation signal can be used to control the duty cycles of the first, second, third, and fourth switches, respectively. The H-bridge circuit can be used to output a first charging voltage or a second charging voltage based on the voltage generation signal and the supply voltage (i.e., the first supply voltage or the second supply voltage) generated and output by the photovoltaic power generation circuit 2.

[0074] See Figure 6 The diagram shown is a structural schematic of an H-bridge circuit provided in an embodiment of this utility model. The H-bridge circuit may include four switches (i.e., first switch Q1, second switch Q2, third switch Q3, and fourth switch Q4) and one inductor (i.e., inductor L1). The first switch Q1, second switch Q2, third switch Q3, and fourth switch Q4 are located in the first, second, third, and fourth arms of the H-bridge, respectively. The two ends of inductor L1 are connected to node A (the first node) between the first switch Q1 and the second switch Q2, and node B (the second node) between the third switch Q3 and the fourth switch Q4, respectively. A voltage generation signal alternately conducts the diagonal arms (i.e., conducts the first switch Q1 and the fourth switch Q4, or conducts the second switch Q2 and the third switch Q3), thereby generating power based on the supply voltage (i.e., the first supply voltage V) output by the photovoltaic power generation circuit 2. S1 Or the second supply voltage V S2It outputs either the first charging voltage or the second charging voltage.

[0075] It should also be noted that, such as Figure 6 As shown, the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4 can all be enhancement-mode N-channel metal-oxide-semiconductor field-effect transistors (MOSFETs). Of course, they can also be other field-effect transistors or switching devices. (The last sentence appears to be incomplete and possibly refers to a different context.) Figure 6 As shown, switch K is a switching unit 133, which is used to connect the first channel 131 or the second channel 132.

[0076] In summary, in the photovoltaic power supply circuit provided in this embodiment of the present invention, the detection module can be used to detect the supply voltage and obtain a voltage detection signal; the voltage detection signal can be used to indicate that the supply voltage is a first supply voltage or a second supply voltage, wherein the first supply voltage is greater than the second supply voltage; the maximum power point tracking module is used to output a first charging voltage based on the first supply voltage, or to output a second charging voltage based on the second supply voltage; the channel switching module includes at least a first channel and a second channel, and the channel switching module can be used to switch the first channel based on the first charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively, or to switch the second channel based on the second charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively; the first channel can be used to output a target charging voltage according to the first charging voltage, and the second channel can be used to output a target charging voltage according to the second charging voltage; the energy storage module can be used to access the target charging voltage through the first channel or the second channel. Therefore, it can be seen that energy storage under different supply voltages can be achieved by using only one maximum power point tracking module. Therefore, it reduces the circuit cost caused by the need to set different maximum power point tracking modules for different supply voltages in related technologies, and improves the problem of wasted circuit resources caused by the existence of idle maximum power point tracking modules in related technologies.

[0077] Furthermore, based on the same technical concept, this utility model embodiment also provides a photovoltaic system, see reference. Figure 7 The diagram shown illustrates an optional photovoltaic system architecture according to an embodiment of this utility model. The photovoltaic system may include: Figures 2-6 The photovoltaic power supply circuit 1 and photovoltaic power generation circuit 2 are shown in the diagram. The output terminal of the photovoltaic power generation circuit 2 is connected to the input terminal of the photovoltaic power supply circuit 1, meaning that the photovoltaic power supply circuit 1 can be connected to the power supply voltage V output by the photovoltaic power generation circuit 2. IN The aforementioned supply voltage is the first supply voltage V. S1 Or the second supply voltage VS2 Optional, the first supply voltage V S1 Greater than the preset power supply voltage V STH Second power supply voltage V S2 Less than or equal to the preset supply voltage V STH .

[0078] In one optional implementation, the photovoltaic power generation circuit 2 may include multiple photovoltaic units arranged in an array, which are used to generate the supply voltage for the photovoltaic power supply circuit 1. It should be noted that the aforementioned multiple photovoltaic units can be combined in series, in parallel, or in a series-parallel configuration; this embodiment of the invention does not specifically limit the specific combination of these units.

[0079] Furthermore, it should be understood that the above-disclosed embodiments are merely preferred embodiments of the present utility model and are not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the content of the technical solution described in the present utility model shall still fall within the scope of the present utility model.

Claims

1. A photovoltaic power supply circuit, characterized in that, Electrically connected to a photovoltaic power generation circuit for outputting the power supply voltage, the photovoltaic power supply circuit includes: a detection module, a maximum power point tracking module, a channel switching module, and an energy storage module connected in sequence; wherein, The detection module is used to detect the power supply voltage and obtain a voltage detection signal; the voltage detection signal is used to indicate that the power supply voltage is a first power supply voltage or a second power supply voltage, wherein the first power supply voltage is greater than the second power supply voltage. The maximum power point tracking module is used to output a first charging voltage based on the first supply voltage, or to output a second charging voltage based on the second supply voltage; The channel switching module includes at least a first channel and a second channel. The channel switching module is used to switch the first channel based on the first charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively, or to switch the second channel based on the second charging voltage so that the channel switching module is connected to the maximum power point tracking module and the energy storage module respectively; the first channel is used to output a target charging voltage according to the first charging voltage, and the second channel is used to output the target charging voltage according to the second charging voltage; The energy storage module is used to access the target charging voltage through the first channel or the second channel.

2. The photovoltaic power supply circuit as described in claim 1, characterized in that, The channel switching module includes: a switching unit, a first channel, and a second channel; wherein... The first channel includes a first conversion unit, which is used to perform voltage conversion processing on the first charging voltage and output the target charging voltage; The second channel includes a second conversion unit, which is used to perform voltage conversion processing on the second charging voltage and output the target charging voltage; One end of the switching unit is connected to the maximum power point tracking module, and the other end of the switching unit is used to connect to the first conversion unit or the second conversion unit; The first input terminal of the energy storage module is electrically connected to the output terminal of the first conversion unit, and the second input terminal of the energy storage module is electrically connected to the output terminal of the second conversion unit.

3. The photovoltaic power supply circuit as described in claim 1, characterized in that, The first charging voltage is greater than the target charging voltage, and the second charging voltage is equal to the target charging voltage. The channel switching module includes: a switching unit, a first channel, and a second channel; wherein... The first channel includes a first conversion unit, which is used to step down the first charging voltage and output the target charging voltage. The second channel includes a conductor line; One end of the switching unit is connected to the maximum power point tracking module, and the other end of the switching unit is used to connect to the first conversion unit or the conductor line; The first input terminal of the energy storage module is electrically connected to the output terminal of the first conversion unit, and the second input terminal of the energy storage module is electrically connected to the conductor line.

4. The photovoltaic power supply circuit as described in claim 2 or 3, characterized in that, The switching unit is a single-pole double-throw switch.

5. The photovoltaic power supply circuit as described in claim 2 or 3, characterized in that, The first conversion unit includes an LLC resonant circuit.

6. The photovoltaic power supply circuit as described in claim 5, characterized in that, A bus is provided between the maximum power point tracking module and the LLC resonant circuit, and the first charging voltage is determined based on the bus voltage.

7. The photovoltaic power supply circuit as described in claim 6, characterized in that, The bus voltage is greater than the first supply voltage, and the maximum power point tracking module includes: The third conversion unit has its input terminal connected to the detection module and its output terminal electrically connected to the busbar. The third conversion unit is used to boost the first power supply voltage and output the first charging voltage when the voltage detection signal indicates that the power supply voltage is the first power supply voltage; Furthermore, when the voltage detection signal indicates that the power supply voltage is the second power supply voltage, the second power supply voltage is subjected to voltage conversion processing to output the second charging voltage.

8. The photovoltaic power supply circuit as described in claim 7, characterized in that, The maximum power point tracking module also includes: The control unit is electrically connected to the third conversion unit, the channel switching module, and the detection module, respectively. The control unit is configured to generate a first switching signal when the voltage detection signal indicates that the supply voltage is the first supply voltage; the first switching signal is configured to instruct the channel switching module to switch the output channel of the target charging voltage to the first channel and control the third conversion unit to boost the first supply voltage to the first charging voltage; or, when the voltage detection signal indicates that the supply voltage is the second supply voltage, the control unit generates a second switching signal; the second switching signal is configured to instruct the channel switching module to switch the output channel of the target charging voltage to the second channel and control the third conversion unit to convert the second supply voltage to the second charging voltage.

9. The photovoltaic power supply circuit as described in claim 7 or 8, characterized in that, The third conversion unit includes an H-bridge circuit composed of a first switch, a second switch, a third switch, a fourth switch, and an inductor; wherein the first switch, the second switch, the third switch, and the fourth switch are respectively disposed on the first arm, the second arm, the third arm, and the fourth arm of the H-bridge circuit, one end of the inductor is connected to a first node between the first switch and the second switch, and the other end of the inductor is connected to a second node between the third switch and the fourth switch.

10. A photovoltaic system, characterized in that, include: A photovoltaic power generation circuit and a photovoltaic power supply circuit as described in any one of claims 1-9, wherein the output terminal of the photovoltaic power generation circuit is electrically connected to the input terminal of the photovoltaic power supply circuit; wherein, The photovoltaic power generation circuit includes: a plurality of photovoltaic modules arranged in an array, the plurality of photovoltaic modules being used to output the power supply voltage of the photovoltaic power supply circuit; the power supply voltage is a first power supply voltage or a second power supply voltage, wherein the first power supply voltage is greater than the second power supply voltage.

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