Photovoltaic module control circuit, photovoltaic power generation device, electric equipment and vehicle

Abstract

The utility model provides a photovoltaic assembly control circuit, a photovoltaic power generation device and electric equipment. The photovoltaic assembly control circuit comprises at least one first switch element; the first switch element is arranged at the positive electrode output end or the negative electrode output end of the photovoltaic module, and the first switch element is used for controlling electric signal output of the photovoltaic module. The control circuit adopts passive driving, and ensures balanced current output when the system works; the response speed is high, the requirement of function safety is met, and the system reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic, and more particularly to a control circuit for photovoltaic modules, a photovoltaic power generation device, an electric device and a vehicle. Background Art

[0002] At present, most photovoltaic power generation systems adopt a series structure. After being connected in series, the photovoltaic modules will form a direct current high voltage of thousands of volts, which poses a safety risk to personnel in situations such as maintenance and fire fighting. Therefore, when the photovoltaic modules are in an unoperated state, the output voltage at the ports should not be higher than 60V. When a load fails, the output of the photovoltaic modules can be quickly turned off to protect the electrical appliances and personnel safety.

[0003] The existing control circuit for photovoltaic modules draws power from one photovoltaic module, resulting in current imbalance during system operation; and abnormal power-off or faults may cause the control circuit to malfunction. Summary of the Utility Model

[0004] The present utility model is proposed in view of the above problems. The present utility model provides a control circuit for photovoltaic modules, a photovoltaic power generation device, an electric device and a vehicle, which adopts passive drive to ensure balanced current output during system operation; has a fast response speed, meets the requirements of functional safety, and improves the reliability of the system.

[0005] In a first aspect of the present utility model, there is provided a control circuit for photovoltaic modules, the control circuit for photovoltaic modules comprising: at least one first switching element;

[0006] The first switching element is disposed at the positive output terminal or the negative output terminal of the photovoltaic module, and the first switching element is used to control the electrical signal output of the photovoltaic module.

[0007] In an embodiment of the present utility model, the first switching element is connected in series between two adjacent photovoltaic modules.

[0008] In an embodiment of the present utility model, the control circuit for photovoltaic modules further comprises at least one isolation driving circuit. The first output terminal of each isolation driving circuit is connected to the control terminal of the corresponding first switching element, and the second output terminal of the isolation driving circuit is connected to the first terminal of the corresponding first switching element. A control signal is input to the photovoltaic module via the input terminal of the isolation driving circuit.

[0009] In an embodiment of the present utility model, the isolation driving circuit comprises: a push-pull isolation power supply, a full-bridge rectifier circuit, and a filter circuit;

[0010] The first output terminal of the push-pull isolated power supply is connected to the first input terminal of the full-bridge rectifier circuit, and the second output terminal of the push-pull isolated power supply is connected to the second input terminal of the full-bridge rectifier circuit;

[0011] The first output terminal of the full-bridge rectifier circuit is connected to the first input terminal of the filter circuit, and the second output terminal of the full-bridge rectifier circuit is connected to the second input terminal of the filter circuit;

[0012] The first output terminal of the filter circuit is connected to the control terminal of the first switching element, and the second output terminal is connected to the first terminal of the first switching element.

[0013] In an embodiment of the present invention, the isolation drive circuit further includes a zener diode;

[0014] The positive terminal of the zener diode is connected to the first terminal of the first switching element, and the negative terminal is connected to the control terminal of the first switching element.

[0015] In an embodiment of the present invention, when the number of the isolation drive circuits is greater than or equal to 2, the input terminals of the isolation drive circuits are connected in parallel.

[0016] In an embodiment of the present invention, the push-pull isolated power supply includes a first PWM generator and a dual-winding transformer, and the dual-winding transformer includes a primary coil and a secondary coil;

[0017] The first output terminal and the second output terminal of the first PWM generator are respectively connected to the first lead-out terminal and the second lead-out terminal of the primary coil, the input terminal of the first PWM generator is connected to the center tap of the primary coil, and the input terminal of the first PWM generator is used as the input terminal of the isolation drive circuit to input the control signal of the photovoltaic module;

[0018] The lead-out terminal of the secondary coil is used as the output terminal of the push-pull isolated power supply and is connected to the input terminal of the full-bridge rectifier circuit.

[0019] In an embodiment of the present invention, the push-pull isolated power supply includes a second PWM generator, a second switching element, a third switching element, a fourth switching element, a first resistor, and a single-winding transformer;

[0020] The single-winding transformer includes a primary coil and a secondary coil. The first lead-out terminal and the second lead-out terminal of the primary coil are respectively connected to the first terminal and the second terminal of the second switching element. The lead-out terminal of the secondary coil is used as the output terminal of the push-pull isolated power supply and is connected to the input terminal of the full-bridge rectifier circuit;

[0021] The first end of the third switching element is grounded, and the second end is connected to the second end of the second switching element; the control ends of the second switching element and the third switching element are both connected to the first end of the fourth switching element;

[0022] The second end of the fourth switching element is grounded, the first end of the fourth switching element is connected to one end of the first resistor, the other end of the first resistor is connected to the circuit power supply, and the control end of the fourth switching element is connected to the output end of the second PWM generator;

[0023] The input end of the second PWM generator serves as the input end of the isolation drive circuit for inputting the control signal of the photovoltaic module.

[0024] In an embodiment of the present invention, the full-bridge rectifier circuit includes: a second switching element, a third switching element, a sixth switching element, and a seventh switching element;

[0025] The positive pole of the second switching element and the negative pole of the third switching element are connected, and the connection point serves as the first input end of the full-bridge rectifier circuit;

[0026] The positive pole of the sixth switching element and the negative pole of the seventh switching element are connected, and the connection point serves as the first input end of the full-bridge rectifier circuit;

[0027] The negative poles of the second switching element and the sixth switching element are connected, and the connection point serves as the first output end of the full-bridge rectifier circuit;

[0028] The positive poles of the third switching element and the seventh switching element are connected, and the connection point serves as the second output end of the full-bridge rectifier circuit.

[0029] In an embodiment of the present invention, the filter circuit includes a first capacitor, a second resistor, and a third resistor, and the first capacitor and the second resistor are connected in parallel and then connected in series with the third resistor.

[0030] In an embodiment of the present invention, the photovoltaic module control circuit further includes at least one first balancing protection circuit, each first balancing protection circuit includes a first end and a second end, the first end of the first balancing protection circuit is connected to the first end of the corresponding first switching element, and the second end of the first balancing protection circuit is connected to the second end of the corresponding first switching element.

[0031] In an embodiment of the present invention, the first balancing protection circuit includes a transient voltage suppression diode, a balancing resistor, and an RC circuit, and the transient voltage suppression diode, the balancing resistor, and the RC circuit are connected in parallel.

[0032] In an embodiment of the present utility model, the photovoltaic module control circuit further includes at least one diode;

[0033] The positive electrode of each diode is connected to the negative electrode of the corresponding photovoltaic module, and the negative electrode of each diode is connected to the positive electrode of the corresponding photovoltaic module.

[0034] In an embodiment of the present utility model, the first switching element is one of a MOS field effect transistor, a solid state switch, and an insulated gate bipolar transistor.

[0035] The second aspect of the present utility model provides a photovoltaic power generation device, including:

[0036] A photovoltaic string, the photovoltaic string includes at least two photovoltaic modules;

[0037] At least one photovoltaic module control circuit according to any one of the above first aspects, and the first switching element in the photovoltaic module control circuit is connected in series between two adjacent photovoltaic modules.

[0038] The third aspect of the present utility model provides an electric device, and the electric device includes the photovoltaic power generation device described in the above second aspect.

[0039] The fourth aspect of the present utility model provides a vehicle, and the vehicle includes the photovoltaic power generation device described in the above second aspect.

[0040] For the photovoltaic module control circuit of the embodiment of the present utility model, the isolation drive circuit adopts passive drive, and the connection or disconnection of the photovoltaic module can be realized without taking power from the photovoltaic module, ensuring the balanced output of current during system operation; when the output of the photovoltaic panel is abnormal during operation, the response speed is fast, thus meeting the requirements of functional safety and ensuring personal safety; since the isolation drive circuit adopts passive drive, the operation of the control circuit will not be affected by power supply failures, improving the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] By describing the embodiments of the present utility model in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present utility model will become more obvious. The drawings are used to provide a further understanding of the embodiments of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model, and do not constitute a limitation to the present utility model. In the drawings, the same reference numerals generally represent the same components or steps.

[0042] Figure 1 is a schematic structural diagram of a photovoltaic module control circuit according to an embodiment of the present utility model;

[0043] Figure 2Schematic structural diagram of a photovoltaic module control circuit when multiple photovoltaic modules are connected in series according to an embodiment of the present invention;

[0044] Figure 3 Schematic structural diagram of a first balancing protection circuit according to an embodiment of the present invention;

[0045] Figure 4 Schematic structural diagram of a photovoltaic module control circuit according to another embodiment of the present invention;

[0046] Figure 5 Schematic structural diagram of a photovoltaic module control circuit according to still another embodiment of the present invention;

[0047] Figure 6 Schematic structural diagram of an isolation drive circuit according to an embodiment of the present invention;

[0048] Figure 7 Schematic structural diagram of a photovoltaic power generation device according to an embodiment of the present invention. Detailed implementation manners

[0049] In order to make the objectives, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments of the present invention. It should be understood that the present invention is not limited by the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

[0050] First, refer to Figure 1 to describe the photovoltaic module control circuit according to the embodiment of the present invention. The photovoltaic module control circuit of the present invention can be applied to a photovoltaic power generation system. The photovoltaic power generation system includes one or more photovoltaic strings, and the photovoltaic string includes at least two photovoltaic modules, which are connected in series or in parallel. Specifically, the circuit of the present invention is used to control the on / off of the series or parallel connection circuit of the photovoltaic modules.

[0051] The photovoltaic power generation system can be a vehicle-mounted photovoltaic power generation system or a photovoltaic power generation system in other electric devices. The present application does not make specific limitations thereto.

[0052] Such as Figure 1As shown in the figure, the present application proposes a photovoltaic module control circuit. The photovoltaic module control circuit 100 includes: at least one first switching element 101, which is arranged at the positive output terminal or the negative output terminal of the photovoltaic module 200, and the first switching element 101 is used to control the electrical signal output of the photovoltaic module 200.

[0053] The first switching element 101 is used to control the on and off of the output circuit connection of the photovoltaic module 200 under the drive of a drive signal, so as to control the electrical signal output of the photovoltaic module 200.

[0054] Specifically, the first switching element 101 can be one of a metal-oxide-semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET), hereinafter referred to as MOS field-effect transistor, a solid-state switch, and an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT). The first switching element can also be other fully controlled power switching devices, and the present utility model does not make specific limitations thereto.

[0055] Exemplarily, when the first switching element 101 is a MOS field-effect transistor, the control terminal of the first switching element 101 is the gate, and the first terminal is the source.

[0056] When a drive signal is input to the control terminal of the first switching element 101, the first switching element 101 is in an on state, so that the photovoltaic string can supply power outward; when there is no drive signal, at this time the power transistor changes from an on state to a cut-off state, and each photovoltaic module is relatively independent and has no output.

[0057] The photovoltaic module control circuit of the embodiment of the present utility model can be applied to the scenario where multiple groups of photovoltaic modules are connected in series or in parallel. The isolation drive circuit adopts passive drive, and the series connection or shutdown of the photovoltaic modules can be realized without taking power from the photovoltaic modules, ensuring the balanced output of current during system operation; if the output of the photovoltaic panel is abnormal during the working process, the drive circuit can quickly disconnect the photovoltaic panel, so that the originally series-connected photovoltaic power supply system is cut off into independent photovoltaic modules, with a fast response speed, thus meeting the requirements of functional safety and ensuring personal safety; since the isolation drive circuit adopts passive drive, the operation of the control circuit will not be affected by power supply failures, improving the reliability of the system.

[0058] In addition, when the first switching element adopts a MOS field-effect transistor, the voltage withstand of the MOS field-effect transistor only needs to be 2 to 3 times that of the photovoltaic module, saving costs, and the MOS with low voltage withstand has a lower on-resistance, thereby reducing heat loss and improving efficiency.

[0059] Next, refer to Figure 2Describe the photovoltaic module control circuit according to an embodiment of the present invention.

[0060] Figure 2 The multiple photovoltaic modules shown in are connected in series. At this time, each first switching element 101 is sequentially connected in series between two adjacent photovoltaic modules 200 in the photovoltaic string.

[0061] Since the series connection of photovoltaic modules requires connecting the positive electrode of the next-level photovoltaic panel to the negative electrode of the previous-level photovoltaic panel and connecting them in series in turn, and the potentials of each series connection node are different. Therefore, in an embodiment of the present invention, the photovoltaic module control circuit further includes at least one isolation drive circuit. The first output end of each isolation drive circuit 102 is connected to the control end of the corresponding first switching element 101, and the second output end of the isolation drive circuit is connected to the first end of the corresponding first switching element 101. A control signal is input to the photovoltaic string through the input end of the isolation drive circuit.

[0062] The isolation drive circuit 102 is used to input a drive signal to the control end of the first switching element 101 to control the first switching element 101 to conduct, so that the photovoltaic string can supply power to the outside; when the drive signal input to the control end of the first switching element 101 is stopped, the first switching element 101 is controlled to interrupt, so that the photovoltaic string can stop supplying power to the outside.

[0063] In an embodiment of the present invention, the photovoltaic module control circuit further includes at least one first balancing protection circuit. Each first balancing protection circuit is connected in parallel with the corresponding first switching element. Specifically, each first balancing protection circuit includes a first end and a second end. The first end of the first balancing protection circuit is connected to the first end of the corresponding first switching element, and the second end of the first balancing protection circuit is connected to the second end of the corresponding first switching element.

[0064] It should be noted that when the photovoltaic modules are connected in series and in parallel, the circuit composition of the photovoltaic module control circuit is the same, and the only difference is the position of the first switching element. Therefore, the following will take the series connection of photovoltaic modules as an example for description.

[0065] Next, refer to Figure 3 to describe the first balancing protection circuit according to an embodiment of the present invention.

[0066] In this embodiment, the first switching element is a MOS field effect transistor Qn1.

[0067] As Figure 3 shown, the first balancing protection circuit includes a transient voltage suppressor (TVS) D11, a balancing resistor R12 connected in parallel, and an RC circuit composed of a resistor R11 and a capacitor C11.

[0068] Since the breakdown voltage of the MOS used is generally 2 to 3 times the output voltage of the photovoltaic module, and this voltage is much smaller than the total voltage after series connection. If the turn-on speeds of the MOS transistors are inconsistent, it is very likely that the MOS transistor that turns on later will be broken down due to insufficient breakdown voltage. In this embodiment, a TVS, a balancing resistor, and an RC circuit are provided between the drain and source of the MOS field-effect transistor, which can effectively prevent the MOS field-effect transistor that turns on later from being broken down due to insufficient breakdown voltage caused by differences in the turn-on times of multiple MOSs.

[0069] The RC circuit is connected in parallel between the drain and base of the MOS field-effect transistor Qn1, which can prevent the MOS from turning on too fast to relieve the balancing pressure.

[0070] If the capacitance C11 is selected too large, it will cause the MOS transistor to turn on too slowly, increase the loss and even damage the MOS transistor. Therefore, a film capacitor with a capacitance less than 1 uF is selected, and its current is limited by a resistor. The resistance value of the resistor should be:

[0071] R 11 = V P / I DM

[0072] Among them, R 11 is the resistance value of the resistor in the RC circuit, I DM is the rated current of the MOS transistor, and V P is the voltage of a single photovoltaic panel.

[0073] The balancing resistor R12 is used to ensure the voltage balance between multiple levels of MOSs. Due to the process differences in the manufacturing process of MOS transistors, the leakage current of each MOS transistor in the off state is different. For example, in the off state of the MOS transistor, the maximum leakage current I DSS is about 1 uA. At this time, the value of the balancing resistor is 3 to 5 times the equivalent impedance of the MOS field-effect transistor. The calculation formula for the equivalent impedance R ZK of the MOS field-effect transistor is as follows:

[0074] R ZK = V P / I DSS

[0075] Among them, V P is the voltage of a single photovoltaic panel, and I DSS is the leakage current of the MOS transistor.

[0076] The TVS tube is used for clamping. In the application scenario where multiple photovoltaic modules are connected in series, the TVS tube is a unidirectional TVS tube, and its breakdown voltage is 80% - 85% of the rated breakdown voltage V DS of the MOS transistor.

[0077] When the resistor-capacitor fails for some reason, the TVS tube can clamp the voltage V between the drain and source of the MOS field-effect transistor within the rated breakdown voltage V of the MOS field-effect transistor. Then the MOS field-effect transistor conducts, and the overvoltage stress disappears. Therefore, the TVS tube can effectively ensure that the MOS field-effect transistor will not be broken down due to the difference in turn-on time when it is turned on. DS of the MOS field-effect transistor, DS subsequently, the MOS field-effect transistor conducts, and the overvoltage stress disappears. Therefore, the TVS tube can effectively ensure that the MOS field-effect transistor will not be broken down due to the difference in turn-on time when it is turned on.

[0078] In an embodiment of the present invention, the photovoltaic module control circuit further includes at least one diode; the diode is correspondingly arranged with the photovoltaic module, the positive electrode of each diode is connected to the negative electrode of the corresponding photovoltaic module, and the negative electrode of each diode is connected to the positive electrode of the corresponding photovoltaic module.

[0079] Next, refer to Figure 4 to describe the photovoltaic module control circuit according to an embodiment of the present invention.

[0080] As Figure 4 shown, the photovoltaic string includes N solar panels, namely solar panel 1, solar panel 2... solar panel N, SOLN+ and SOLN- respectively represent the positive and negative electrodes of the solar panel. The MOS field-effect transistor Qnn is connected in series between SOLN- of solar panel n and SOLN+ of solar panel n-1. At the same time, a diode Dn2 is connected in parallel between SOLN+ and SOLN- of solar panel N. A unidirectional transient suppression diode Dn1, a balancing resistor Rn2, and an RC circuit composed of a resistor Rn1 and a capacitor Cn1 are arranged in parallel with the MOS field-effect transistor Qnn.

[0081] The power devices Qn1, Qn2,..., Qnn connected in series between multiple solar panels are enhancement-type MOS field-effect transistors (hereinafter referred to as MOS transistors). When there is no drive signal, the MOS transistors are turned off, and each photovoltaic module is relatively independent and has no output. When there is a drive signal, the PN junction of the MOS transistor conducts, and the photovoltaic modules are connected in series, so as to achieve the purpose of controllably connecting the photovoltaic modules in series.

[0082] When the solar panel operates normally, the diode is turned off; when one of the solar panels fails, the diode conducts.

[0083] By connecting the diode in parallel, when a photovoltaic module in the photovoltaic string fails, the diode connected in parallel with it will conduct to bypass the faulty photovoltaic module, which will not affect the operation of the entire photovoltaic system, ensure the normal operation of the system, thereby reducing the system failure rate and greatly extending the service life of the system.

[0084] Please continue to refer to Figure 4, in this embodiment, a soft-start protection circuit is further provided to control whether the photovoltaic modules are connected in series and discharged externally through the MOS transistor. The soft-start protection circuit is connected in series to the positive output bus SOL_BUS+ of the photovoltaic string, and specifically includes MOS field-effect transistors QA1 and QB1. The source of the MOS field-effect transistor QA1 is connected to the drain of the MOS field-effect transistor QB1. The drain of the MOS field-effect transistor QA1 is connected to the positive pole SOLN+ of the solar panel N. A resistor Rm is connected between the source and the drain of the MOS field-effect transistor QB1. The source of the MOS field-effect transistor QB1 is connected to the output end of the positive output bus SOL_BUS+. A capacitor Cm is provided between the positive output bus SOL_BUS+ and the negative output bus SOL_BUS-.

[0085] In actual operation, the conduction of the MOS transistor is controlled by the isolation drive circuit. Before the system officially operates, the system is first powered on and detected. The discharge capacity of the photovoltaic modules and whether there is a fault at the load end are detected, such as whether the load is short-circuited or open-circuited; if the discharge capacity is weak or a line fault occurs, then control QA1 to turn off the output and cut off the loop current. If the discharge capacity is sufficient, the system circuit is fault-free, and the load is normal, then the MOS field-effect transistors QA1 and QB1 are turned on, and the electric energy is stored in the bus capacitor and then connected to the inverter and other systems for normal power generation. Through the soft-start protection circuit, the normal output of the photovoltaic modules can be guaranteed, and it can also effectively prevent the safety hazard to the human body caused by too high port voltage in the non-working state, such as the maintenance state, and ensure the personal safety of transportation, installation, wiring personnel, and vehicle occupants in case of a fault.

[0086] In an embodiment of the present application, when the number of isolation drive circuits is greater than or equal to 2, the input ends of the isolation drive circuits are connected in parallel.

[0087] When the input ends of each isolation drive circuit are connected in parallel, through one control signal, multiple isolation drive circuits can be input simultaneously, and the drive circuit can issue drive signals to connect or turn off multiple photovoltaic modules in series at the same time, thereby realizing the simultaneous control of multiple nodes of the photovoltaic modules.

[0088] In an embodiment of the present application, the isolation drive circuit includes: a push-pull isolation power supply, a full-bridge rectifier circuit, and a filter circuit;

[0089] The first output end of the push-pull isolation power supply is connected to the first input end of the full-bridge rectifier circuit, and the second output end of the push-pull isolation power supply is connected to the second input end of the full-bridge rectifier circuit;

[0090] The first output end of the full-bridge rectifier circuit is connected to the first input end of the filter circuit, and the second output end of the full-bridge rectifier circuit is connected to the second input end of the filter circuit;

[0091] The first output terminal of the filter circuit is connected to the control terminal of the first switching element, and the second output terminal is connected to the first end of the first switching element.

[0092] In this embodiment, the push-pull isolated power supply is used to output an AC signal. The push-pull isolated power supply includes an isolation transformer. A pulse width modulation (PWM) signal is applied to the primary winding of the isolation transformer, and an AC signal is coupled out from the secondary winding of the isolation transformer.

[0093] In this embodiment, the full-bridge rectifier circuit is used to convert the AC signal into a DC voltage signal. The zener diode is used to clamp the DC voltage signal.

[0094] In an embodiment of the present application, the isolation drive circuit further includes a zener diode;

[0095] The positive terminal of the zener diode is connected to the first end of the first switching element, and the negative terminal is connected to the control terminal of the first switching element.

[0096] In an embodiment of the present application, the full-bridge rectifier circuit may include: a second switching element, a third switching element, a sixth switching element, and a seventh switching element;

[0097] The positive electrode of the second switching element and the negative electrode of the third switching element are connected, and the connection point serves as the first input terminal of the full-bridge rectifier circuit;

[0098] The positive electrode of the sixth switching element and the negative electrode of the seventh switching element are connected, and the connection point serves as the first input terminal of the full-bridge rectifier circuit;

[0099] The negative electrode of the second switching element and the negative electrode of the sixth switching element are connected, and the connection point serves as the first output terminal of the full-bridge rectifier circuit;

[0100] The positive electrode of the third switching element and the positive electrode of the seventh switching element are connected, and the connection point serves as the second output terminal of the full-bridge rectifier circuit.

[0101] Here, the switching element may be a diode.

[0102] Next, refer to Figure 5 to describe the photovoltaic module control circuit according to an embodiment of the present invention.

[0103] In this embodiment, the push-pull isolated power supply includes a first PWM generator and a dual-winding transformer.

[0104] The photovoltaic module control circuit includes a first switching element, a first balancing protection circuit, a diode, and an isolation drive circuit corresponding to each solar panel. In this embodiment, for the structures and functions of the first switching element, the first balancing protection circuit, and the diode, please refer to the above description. Here, only the isolation drive circuit will be described.

[0105] As Figure 5 shown, T1, T2, ……, Tn are drive isolation transformers. In this embodiment, the drive isolation transformer is a dual-winding transformer, and the dual-winding transformer includes a primary coil and a secondary coil. UL1, UL2, ……, ULn are the first PWM generators. Specifically, the first PWM generators are drive chips capable of generating PWM signals.

[0106] The isolation drive circuit of solar panel N will be taken as an example for illustration below.

[0107] The push-pull isolation power supply includes the first PWM generator ULn and the dual-winding transformer Tn. The first output terminal and the second output terminal of the first PWM generator ULn are respectively connected to the first lead-out terminal and the second lead-out terminal of the primary coil. The input terminal of the first PWM generator ULn is connected to the center tap of the primary coil. The input terminal of the first PWM generator ULn serves as the input terminal of the isolation drive circuit for inputting the control signal of the photovoltaic module; the lead-out terminal of the secondary coil serves as the output terminal of the push-pull isolation power supply and is connected to the input terminal of the full-bridge rectifier circuit.

[0108] The input terminals of the first PWM generators UL1, UL2, ……, ULn are connected in parallel. When it is necessary to turn on the MOS transistors, a 5V voltage signal can be input to the input terminal of the first PWM generator ULn. The isolated drive signal can turn on all the MOS transistors at the series nodes simultaneously, connect the photovoltaic panels in series at the same time, and obtain the total voltage after series connection on SOL_BUS+ for the system to use, thereby effectively preventing excessive voltage difference at the V DS port of the diode that conducts later due to inconsistent conduction speeds and resulting in losses. Similarly, removing the 5V signal at the "series control signal" port can turn off all the MOS transistors at the nodes simultaneously. It is functionally safe and can not only protect the MOS transistors but also improve the working efficiency.

[0109] In this embodiment, the isolation drive circuit further includes a full-bridge rectifier circuit. The full-bridge rectifier circuit includes two pairs of symmetric diodes, namely the second diode D2, the third diode D3, the sixth diode D6, and the seventh diode D7. Each pair is connected in a half-bridge configuration. In the full-bridge rectifier circuit, when the positive half-cycle of the input AC signal is present, one pair of diodes conducts and directs the current to the output terminal; when the negative half-cycle of the input AC signal is present, the other pair of diodes conducts and also directs the current to the output terminal. Through the alternating conduction method, the full-bridge rectifier circuit realizes the complete rectification of the input AC signal.

[0110] The full - bridge rectifier circuit has a first AC input terminal, a second AC input terminal, a first DC output terminal, and a second DC output terminal. The first AC input terminal and the second AC input terminal are respectively connected to two lead - out terminals of the secondary coil of the isolation transformer Tn. The first DC output terminal and the second DC output terminal are respectively connected to the first input terminal and the second input terminal of the filter circuit.

[0111] In this embodiment, the isolation drive circuit further includes a zener diode D4. The positive terminal of the zener diode D4 is connected to the source electrode of the MOS transistor Qnn, and the negative terminal of the zener diode D4 is connected to the gate electrode of the MOS transistor Qnn. Specifically, the zener diode D4 is a 15V zener diode. The 15V zener diode can prevent over - voltage from damaging the MOS transistor.

[0112] In this embodiment, the filter circuit includes a second resistor R2, a first capacitor C1, and a third resistor R3. One end of the third resistor R3 is connected to the first DC output terminal of the full - bridge rectifier circuit, the other end of the third resistor R3 is connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is connected to the second DC output terminal of the full - bridge rectifier circuit. The second resistor R2 is connected in parallel with the first capacitor C1, and the second resistor R2 is also connected in parallel with the zener diode D4. The filter circuit can effectively reduce the spikes and noises in the current drive signal.

[0113] When the serial control signal is input into the first PWM generator ULn, the first PWM generator ULn generates a PWM square wave and inputs it into the dual - winding transformer Tn. The voltage is increased through a transformer with a turns ratio of 1:3, and after full - bridge rectification, a high - level voltage not higher than 15V is output to drive the MOS to turn on.

[0114] In an embodiment of the present application, the push - pull isolated power supply can also adopt the form of a push - pull circuit and a single - winding transformer, specifically including a second PWM generator, a second switching element, a third switching element, a fourth switching element, a first resistor, and a single - winding transformer.

[0115] Next, refer to Figure 6 to describe the isolation drive circuit according to an embodiment of the present invention.

[0116] Figure 6 In [description], the isolation drive circuit includes a push - pull isolated power supply, a full - bridge rectifier circuit, and a filter circuit. Among them, the full - bridge rectifier circuit and the filter circuit can refer to the descriptions in the above embodiments, which will not be elaborated here, and only the push - pull isolated power supply will be described.

[0117] Such as Figure 6As shown, the single-winding transformer Tn1 of the push-pull isolated power supply includes a primary coil and a secondary coil. The first lead-out end and the second lead-out end of the primary coil are respectively connected to the first end and the second end of the second switching element Q2. The lead-out end of the secondary coil serves as the output end of the push-pull isolated power supply and is connected to the input end of the full-bridge rectifier circuit.

[0118] The first end of the third switching element Q3 is grounded, and the second end is connected to the second end of the second switching element Q2. The control ends of the second switching element Q2 and the third switching element Q3 are both connected to the first end of the fourth switching element Q4.

[0119] The second end of the fourth switching element Q4 is grounded. The first end of the fourth switching element Q4 is connected to one end of the first resistor R1. The other end of the first resistor R1 is connected to the circuit power supply. The control end of the fourth switching element Q4 is connected to the output end of the second PWM generator via the fourth resistor R4.

[0120] In this embodiment, the second switching element Q2, the third switching element Q3, and the fourth switching element Q4 can be triodes. The second switching element Q2 is an NPN-type triode, and the third switching element Q3 is a PNP-type triode. Correspondingly, the first end of the switching element is the collector, the second end is the emitter, and the control end is the base.

[0121] In this embodiment, the second PWM generator (not shown in the figure) can be a microcontroller unit (MCU), a digital signal processor (DSP), a single-chip microcomputer, an embedded device, or other forms of processors with data processing capabilities and / or instruction execution capabilities, and is used to generate PWM signals.

[0122] The input end of the second PWM generator serves as the input end of the isolation drive circuit for inputting the control signal of the photovoltaic module. The PWM signal input by the second PWM generator is applied to the primary side of the push-pull circuit, modulated into a high-frequency square-wave voltage by the complementary-conducting triodes Q1 and Q2, and sent to the transformer Tn1. The secondary winding of the transformer Tn1 couples out an AC signal, and a DC voltage is output after passing through the secondary rectification and filtering circuit.

[0123] The embodiment of the present application also provides a photovoltaic power generation device. Figure 7 It is a schematic structural diagram of a photovoltaic power generation device according to an embodiment of the present invention. As Figure 7 shown, the photovoltaic power generation device 700 includes:

[0124] A photovoltaic string, and the photovoltaic string includes at least two photovoltaic modules 710;

[0125] The photovoltaic module control circuit of any of the above embodiments includes at least one first switching element 721 and at least one isolation driving circuit 722. The first switching element 721 is connected in series between two adjacent photovoltaic modules 710.

[0126] When the number of photovoltaic modules 710 is greater than or equal to 3, the number of isolation driving circuits 722 is greater than or equal to 2. At this time, the control signal input ends of the isolation driving circuits 722 are connected in parallel.

[0127] The embodiment of the present application also provides an electric device, which includes the photovoltaic power generation device of any of the above embodiments. Specifically, the electric device refers to a device that performs a certain task by electric drive, such as a lawn mower, a lift, etc.

[0128] The embodiment of the present application also provides a vehicle, which includes the photovoltaic power generation device of any of the above embodiments. Specifically, the vehicle can be a pure electric vehicle, a hybrid vehicle, etc. The vehicle adopts this photovoltaic power generation device, which can meet the safety requirements of on-vehicle functions.

[0129] Although example embodiments have been described herein with reference to the drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present invention thereto. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present invention. All such changes and modifications are intended to be included within the scope of the present invention as claimed in the appended claims.

[0130] In the specification provided herein, a large number of specific details are set forth. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures, and technologies have not been shown in detail so as not to obscure the understanding of this specification.

[0131] Similarly, it should be understood that, in order to streamline the present invention and assist in understanding one or more of the various inventive aspects, in the description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present invention should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected by the corresponding claims, the inventive point lies in that the corresponding technical problems can be solved with fewer features than all the features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, where each claim itself serves as a separate embodiment of the present invention.

[0132] Those skilled in the art will understand that, except for features that are mutually exclusive, any combination can be adopted to combine all the features disclosed in this specification (including the accompanying claims, abstract, and drawings), as well as all the processes or units of any method or device thus disclosed. Unless otherwise explicitly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) can be replaced by an alternative feature that provides the same, equivalent, or similar purpose.

[0133] In addition, those skilled in the art will be able to understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of the present utility model and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0134] It should be noted that the above embodiments illustrate the present utility model rather than limit the present utility model, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present utility model can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim listing several devices, several of these devices can be embodied by the same item of hardware. The use of the words first, second, and third, etc. does not denote any order. These words can be interpreted as names.

[0135] As described above, it is only the specific implementation manner of the present utility model or the description of the specific implementation manner. The protection scope of the present utility model is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present utility model, and all should be covered within the protection scope of the present utility model. The protection scope of the present utility model shall be subject to the protection scope of the claims.

Claims

1. A photovoltaic module control circuit, characterized in that: The photovoltaic assembly control circuit comprises: at least one first switching element; The first switch element is disposed at the positive output terminal or the negative output terminal of the photovoltaic component, and the first switch element is used to control the electrical signal output of the photovoltaic component.

2. The photovoltaic module control circuit according to claim 1, characterized in that: The first switch element is connected in series between two adjacent photovoltaic modules.

3. The photovoltaic module control circuit according to claim 1, characterized in that: The photovoltaic component control circuit also includes at least one isolation drive circuit, the first output end of each isolation drive circuit is connected to the control end of the corresponding first switching element, the second output end of the isolation drive circuit is connected to the first end of the corresponding first switching element, and the control signal is input to the photovoltaic component via the input end of the isolation drive circuit.

4. The photovoltaic module control circuit according to claim 3, characterized in that: The isolation driving circuit comprises: a push-pull isolation power supply, a full-bridge rectifier circuit, and a filter circuit; The first output end of the push-pull isolated power supply is connected to the first input end of the full-bridge rectifier circuit, and the second output end of the push-pull isolated power supply is connected to the second input end of the full-bridge rectifier circuit; The first output end of the full-bridge rectifier circuit is connected to the first input end of the filter circuit, and the second output end of the full-bridge rectifier circuit is connected to the second input end of the filter circuit; The first output end of the filter circuit is connected to the control end of the first switch element, and the second output end is connected to the first end of the first switch element.

5. The photovoltaic module control circuit according to claim 4, characterized in that: The isolation driving circuit also includes a voltage regulator tube; The positive terminal of the voltage regulator is connected to the first end of the first switch element, and the negative terminal is connected to the control end of the first switch element.

6. The photovoltaic module control circuit according to claim 4, characterized in that: When the number of the isolation driving circuits is greater than or equal to 2, the input ends of the isolation driving circuits are connected in parallel.

7. The photovoltaic module control circuit according to any one of claims 4 to 6, characterized in that: The push-pull isolated power supply includes a first PWM generator and a dual-winding transformer, wherein the dual-winding transformer includes a primary coil and a secondary coil; The first output terminal and the second output terminal of the first PWM generator are respectively connected to the first lead-out terminal and the second lead-out terminal of the primary coil, the input terminal of the first PWM generator is connected to the center tap of the primary coil, and the input terminal of the first PWM generator is used as the input terminal of the isolation drive circuit to input the control signal of the photovoltaic module; The lead-out end of the secondary coil is connected to the input end of the full-bridge rectifier circuit as the output end of the push-pull isolated power supply.

8. The photovoltaic module control circuit according to any one of claims 4 to 6, characterized in that: The push-pull isolated power supply includes a second PWM generator, a second switch element, a third switch element, a fourth switch element, a first resistor, and a single-winding transformer; The single-winding transformer comprises a primary coil and a secondary coil, the first lead end and the second lead end of the primary coil are respectively connected to the first end and the second end of the second switch element, and the lead end of the secondary coil is connected to the input end of the full-bridge rectifier circuit as the output end of the push-pull isolated power supply; The first end of the third switch element is grounded, and the second end is connected to the second end of the second switch element; the control ends of the second switch element and the third switch element are both connected to the first end of the fourth switch element; The second end of the fourth switch element is grounded, the first end of the fourth switch element is connected to one end of the first resistor, the other end of the first resistor is connected to a circuit power supply, and the control end of the fourth switch element is connected to the output end of the second PWM generator; The input end of the second PWM generator is used as the input end of the isolation drive circuit to input the control signal of the photovoltaic component.

9. The photovoltaic module control circuit according to any one of claims 4 to 6, characterized in that: The full-bridge rectifier circuit includes: a second switch element, a third switch element, a sixth switch element and a seventh switch element; The positive electrode of the second switch element and the negative electrode of the third switch element are connected, and the connection point serves as the first input terminal of the full-bridge rectifier circuit; The positive electrode of the sixth switch element and the negative electrode of the seventh switch element are connected, and the connection point serves as the first input terminal of the full-bridge rectifier circuit; The cathode of the second switch element and the cathode of the sixth switch element are connected, and the connection point serves as the first output end of the full-bridge rectifier circuit; The positive electrode of the third switching element and the positive electrode of the seventh switching element are connected, and the connection point serves as the second output end of the full-bridge rectifier circuit.

10. The photovoltaic assembly control circuit according to any one of claims 4 to 6, characterized in that: The filter circuit includes a first capacitor, a second resistor, and a third resistor. The first capacitor and the second resistor are connected in parallel and then connected in series with the third resistor.

11. The photovoltaic module control circuit according to claim 1, characterized in that: The photovoltaic component control circuit also includes at least one first balancing protection circuit, each of the first balancing protection circuits includes a first end and a second end, the first end of the first balancing protection circuit is connected to the first end of the corresponding first switching element, and the second end of the first balancing protection circuit is connected to the second end of the corresponding first switching element.

12. The photovoltaic module control circuit according to claim 11, characterized in that: The first balancing protection circuit comprises a transient voltage suppression diode, a balancing resistor and an RC circuit, and the transient voltage suppression diode, the balancing resistor and the RC circuit are connected in parallel.

13. The photovoltaic module control circuit according to claim 11, characterized in that: The photovoltaic module control circuit also includes at least one diode; The positive electrode of each diode is connected to the negative electrode of the corresponding photovoltaic component, and the negative electrode of each diode is connected to the positive electrode of the corresponding photovoltaic component.

14. The photovoltaic module control circuit according to claim 1, characterized in that: The first switch element is one of a MOS field effect transistor, a solid-state switch, and an insulated gate bipolar transistor.

15. A photovoltaic power generation device, characterized in that: include: A photovoltaic string, wherein the photovoltaic string includes at least two photovoltaic modules; At least one photovoltaic assembly control circuit according to any one of claims 1 to 14, wherein a first switch element in the photovoltaic assembly control circuit is connected in series between two adjacent photovoltaic assemblies.

16. An electric device, characterized in that: The electric device comprises the photovoltaic power generation device according to claim 15.

17. A vehicle, characterized in that: The vehicle includes the photovoltaic power generation device according to claim 15.

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