Solar power generation assembly control device

Abstract

To provide a photovoltaic power generation assembly control device.SOLUTION: A photovoltaic power generation assembly control device includes at least one bypass module, a driving circuit, a power supply module, and a controller. The at least one bypass module is used to be connected in parallel to at least one photovoltaic power generation assembly. The driving circuit is used to operationally drive the at least one bypass module under control of the controller. The power supply module is used to obtain electric energy from the at least one photovoltaic power generation assembly and output the electric energy to the controller in a case where the at least one photovoltaic power generation assembly operates normally and where the at least one photovoltaic power generation assembly is bypassed. The controller is used to control a conduction state of the at least one bypass module to control whether the at least one photovoltaic power generation assembly is in a bypass mode.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] This application relates to the technical field of photovoltaic power generation, and particularly to a photovoltaic power generation assembly control device.

Background Art

[0002] Photovoltaic power generation technology is one of the currently widely used clean energy technologies. A photovoltaic power generation inverter-connected power system consists of a photovoltaic power generation array and an inverter system. The photovoltaic power generation array is composed of a plurality of photovoltaic power generation assemblies connected in series, and provides sufficient and stable electrical energy to the photovoltaic power generation system. A photovoltaic power generation assembly is an indivisible minimum photovoltaic power generation battery combination device with packaging that can provide a DC power output independently, and is also called a solar cell assembly or a solar cell panel. A photovoltaic power generation assembly consists of a plurality of battery sheet units and a parallel-connected reverse protection diode. A rapid shutdown device is a protection mechanism commonly used in photovoltaic power generation systems.

[0003] Conventional control devices are series-connected control devices, that is, there is a switch transistor connected in series in the voltage output circuit of the photovoltaic power generation assembly. When the photovoltaic power generation system generates power normally, the series-connected switch transistor is always in a conducting state, ensuring the series connection conduction of the assembly and the normal operation of the photovoltaic power generation system. When there are safety problems or safety failures in the system, the series-connected switch transistor is cut off, the series-connected photovoltaic power generation array is cut off, the voltage at any interface of the array meets the safety regulation threshold value, and the safety of the inverter system is protected.

[0004] The above series-connected control device has a major defect. When the series-connected switch transistor is in the normally-off state, a large amount of conduction energy consumption of the switch transistor occurs, and the power generation efficiency decreases.

Summary of the Invention

Problems to be Solved by the Invention

[0005] In view of this, an embodiment of the present application provides a solar power generation assembly control device to solve at least one problem in the background art.

Means for Solving the Problem

[0006] According to a first aspect, an embodiment of the present application is a solar power generation assembly control device, including at least one bypass module, a drive circuit, a power supply module, and a controller. The at least one bypass module is used to be connected in parallel with at least one solar power generation assembly. The power supply module is used to be connected to the at least one solar power generation assembly and the at least one bypass module. The at least one bypass module is used to bypass the at least one solar power generation assembly under the control of the controller. The drive circuit is used to drive the at least one bypass module to operate under the control of the controller. The power supply module is used to obtain electrical energy from the at least one solar power generation assembly when the at least one solar power generation assembly operates normally and when the at least one solar power generation assembly is bypassed, and output the electrical energy to the controller. The controller is used to control the conduction states of the drive circuit and the at least one bypass module to control whether the at least one solar power generation assembly is in a bypass mode, and provides a solar power generation assembly control device.

[0007] In one alternative embodiment in combination with the first aspect of the present application, the at least one bypass module includes a power switch member, an input end and an output end of the power switch member are respectively connected to a positive electrode and a negative electrode of the at least one photovoltaic assembly, and a control end of the power switch member is used to receive a driving signal of the driving circuit.

[0008] In one alternative embodiment in combination with the first aspect of the present application, the at least one bypass module further includes a reverse current protection unit connected in series with the power switch member to prevent the reverse current from damaging the power switch member.

[0009] In one alternative embodiment in combination with the first aspect of the present application, the at least one bypass module further includes a voltage drop adjustment unit for adjusting a voltage drop between an input end and an output end of the at least one bypass module to a predetermined value when the power switch member is in an operating state.

[0010] In one alternative embodiment in combination with the first aspect of the present application, the at least one bypass module further includes at least one diode connected in series with the power switch member.

[0011] In one alternative embodiment in combination with the first aspect of the present application, the power supply module includes a buck circuit for converting a voltage output by the at least one photovoltaic assembly to a second operating voltage when the at least one photovoltaic assembly operates normally.

[0012] In one alternative embodiment in combination with the first aspect of the present application, the power supply module includes a boost circuit for converting a voltage between an input end and an output end of the at least one bypass module to a first operating voltage when the at least one photovoltaic assembly is bypassed.

[0013] In one alternative embodiment in combination with the first aspect of the present application, the power supply module includes a switching circuit for comparing the second operating voltage with a reference voltage and controlling whether to conduct the boost circuit and the at least one bypass module based on the comparison result.

[0014] In one alternative embodiment in combination with the first aspect of the present application, the switching circuit includes a comparator and at least one switch transistor. The first signal input terminal of the comparator is used to receive the second operating voltage output by the buck circuit, the second signal input terminal of the comparator is used to receive a reference signal, the input terminal and the output terminal of the at least one switch transistor are connected to the boost circuit and the bypass module, and the control terminal of the at least one switch transistor is connected to the signal output terminal of the comparator.

[0015] In one alternative embodiment in combination with the first aspect of the present application, the at least one bypass module includes two or more bypass modules connected in series with each other, and the two or more bypass modules connected in series with each other are used to be connected in parallel to at least one photovoltaic assembly.

[0016] In one alternative embodiment in combination with the first aspect of the present application, the controller further includes a communication module, a voltage detection circuit and / or a temperature detection circuit. The communication module is used to receive a control signal and transmit the control signal to the controller. The voltage detection circuit is used to obtain the voltage output by at least one photovoltaic assembly. The temperature detection circuit is used to obtain the temperature of at least one photovoltaic assembly.

Advantages of the Invention

[0017] The photovoltaic power generation assembly control device according to the embodiment of the present application directly connects the bypass module and the photovoltaic power generation assembly in parallel. When the photovoltaic power generation assembly does not need to output a normal operating voltage or operating power, it is put into the bypass mode, and there is no need to serially connect any switch member between the photovoltaic power generation assembly and the bypass module. Therefore, the energy consumption caused by the series-connected switch transistor in the conventional series-connected circuit breaker always being conductive is completely avoided, the power consumption of the control device is greatly reduced, and the output power of the photovoltaic matrix is increased. In addition, the voltage stress problem that the series-connected switch transistor in the series-connected circuit breaker receives when it is first cut off is solved, and the safety performance is improved. After removing the series-connected switch transistor, the circuit structure of the control device is simplified, complex off-logic and timing control requirements are avoided, the reliability of the control device is improved, and the cost is reduced. By directly connecting the bypass module and the photovoltaic power generation assembly in parallel, the faulty assembly can be removed alone without affecting the normal operation of the string system, and the off of a single assembly can be realized.

[0018] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present application.

Brief Description of the Drawings

[0019] The drawings described herein are for providing a further understanding of the present application, constitute a part of the present application, and the exemplary embodiments and descriptions thereof of the present application are for interpreting the present application and do not constitute an undue limitation to the present application. In the drawings,

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Embodiments for Carrying Out the Invention

[0020] To make the technical solution and beneficial effects of this application clearer and easier to understand, the following specific embodiments are enumerated to clearly and completely explain the technical solution of the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of this application.

[0021] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of explaining specific embodiments and are not intended to limit this application.

[0022] As can be understood, terms such as "first" and "second" used in this specification can be used in this specification to describe various elements, but these elements are not limited to these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of this application, the first resistor can be called the second resistor, and similarly, the second resistor can be called the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor. When describing the "first", the "second" does not necessarily exist. When discussing the "second", it does not necessarily indicate that there must be a first element, component, region, layer or part in this application. When used in this specification, the singular forms "one", "a", and "the" may also be intended to include the plural form unless the context clearly indicates otherwise. The meaning of "plural" is two or more unless specifically limited otherwise. It should also be understood that the term "comprising" when used in this specification determines the presence of a feature but does not exclude the presence or addition of one or more other features. When used in this specification, the term "and / or" includes any and all combinations related to the listed items.

[0023] For the sake of clarity, in the context of this application, "connection" means that there is transmission of electrical signals or data between the connected ends, and it can be understood as "electrical connection", "communication connection", etc. "Direct connection between A and B" in the context of this application means that there are no other components other than conducting wires between A and B.

[0024] Figure 1 shows the related art of a solar power generation control device. The solar power generation array includes n solar power generation assemblies connected in series with each other. The solar power generation array outputs electrical energy via a positive voltage output terminal 1 and a negative voltage output terminal 2. A switch is serially connected to the voltage output circuit of each solar power generation assembly, and a switch is parallely connected to the voltage output terminal of each solar power generation assembly. A switch S1 is serially connected to the voltage output circuit of the solar power generation assembly 1, and an anti-reverse diode D1 is parallely connected to the voltage output terminal of the switch of the solar power generation assembly 1 that is serially connected. A switch S2 is serially connected to the voltage output terminal of the solar power generation assembly 2, and an anti-reverse diode D2 is parallely connected to the voltage output terminal of the switch S2 of the solar power generation assembly 2 that is serially connected. A switch Sn is serially connected to the voltage output terminal of the solar power generation assembly n, and an anti-reverse diode Dn is parallely connected to the voltage output terminal of the switch Sn of the solar power generation assembly 3 that is serially connected. A power supply circuit is connected to the voltage output circuit of the solar power generation assembly 1 to provide power supply electrical energy to keep the operation continuous.

[0025] When it is detected that a certain solar power generation assembly has a fault or a safety hazard, the switch serially connected to the solar power generation assembly is cut off. For example, by cutting off S1, the output of the solar power generation assembly is turned off, and the current output by other solar power generation assemblies flows through D1.

[0026] The inventors have discovered the following defects in the above series-connected control device. First, when the photovoltaic assembly is operating normally, the series-connected switch transistors are always conducting, and a large amount of energy consumption occurs in these conducting switch transistors. Second, the series-connected control device has high requirements for off logic and timing control, the control system is complex, and the cost of the control device is high. Third, when the switch transistors in the control device are first cut off, the high-voltage stress of the photovoltaic string system needs to be borne, and there is a risk of overvoltage breakdown. Fourth, in different operating states of the above normal operating state and the turned-off state of the photovoltaic assembly, how to provide a stable and reliable power supply circuit is also an important problem to be solved in this field.

[0027] Therefore, an embodiment of the present application provides a photovoltaic assembly control device including at least one bypass module 10, a drive circuit 20, a power module 40, and a controller 30. The at least one bypass module 10 is connected in parallel to at least one photovoltaic assembly and is used to bypass at least one photovoltaic assembly connected in parallel thereto under the control of the controller 30. When the at least one photovoltaic assembly is bypassed, it is in the bypass mode. The at least one bypass module may be one bypass module or two or more bypass modules. The at least one photovoltaic assembly may be one photovoltaic assembly or two or more photovoltaic assemblies. The at least one bypass module is used to be connected in parallel to at least one photovoltaic assembly. One bypass module may be connected in parallel to one photovoltaic assembly, or one bypass module may be connected in parallel to two or more photovoltaic assemblies, or two or more bypass modules may be connected in series with each other and then connected in parallel to one or two or more photovoltaic assemblies.

[0028] Figure 2 shows an embodiment in which one bypass module 10 is connected in parallel to one photovoltaic assembly. The photovoltaic assembly includes a plurality of cell sheet units, and each cell sheet unit is connected in parallel in the reverse direction to one diode. As shown in Figure 2, D1, D2, and D3 are diodes that are connected in parallel in the reverse direction to the photovoltaic cell sheet units inside the photovoltaic assembly PV, and form a one-way channel for the assembly power supply.

[0029] The bypass module 10 is used to be connected in parallel to one photovoltaic assembly PV1. That is, the voltage input terminal 101 and the voltage output terminal 102 of the bypass module 10 are respectively connected to the positive electrode and the negative electrode of PV1, and there is no switch device between the voltage input terminal 101 and the positive electrode of at least one photovoltaic assembly PV1, and between the voltage output terminal 102 and the negative electrode of PV1. The control terminal 103 of the bypass module 10 is connected to the drive circuit 20 and is used to receive the drive signal output by the drive circuit 20. The bypass module 10 includes a power switch device. Optionally, the power switch device includes a relay, a thyristor, a MOSFET, an IGBT, etc.

[0030] The power supply module 40 is connected to at least one photovoltaic assembly PV1 and at least one bypass module 10, and is used to obtain electrical energy from at least one photovoltaic assembly PV1 and output the electrical energy to the controller 30 and the drive circuit 20 when at least one photovoltaic assembly PV1 operates normally and when at least one photovoltaic assembly PV1 is bypassed. The power supply module 40 can obtain electrical energy in both the normal operation and the bypass mode of the photovoltaic assembly, supply power to the controller 30 and the drive circuit 20, and continue the operation.

[0031] The drive circuit 20 receives the control signal of the controller 30, outputs a drive voltage to at least one bypass module 10 under the control of the controller 30, and drives its operation. The drive circuit 20 further obtains an operating voltage from the power supply module 40.

[0032] The controller 30 is used to control the conduction state of at least one bypass module 10 to control whether the at least one photovoltaic assembly is in the bypass mode. When it is necessary to bypass at least one photovoltaic assembly PV1, the controller 30 outputs a control signal to the drive circuit 20, and the drive circuit 20 further drives the bypass module 10 to conduct, bypass at least one photovoltaic assembly PV1, put it into the bypass mode, and stop the output of electrical energy to the outside. When it is necessary to bypass at least one photovoltaic assembly PV1, it includes the case where a fault or safety accident occurs in the power system, for example, when a DC arc occurs in the photovoltaic assembly, when a fault occurs in the photovoltaic assembly, when a fire occurs, etc.

[0033] When turning off the photovoltaic assembly using a conventional series-connected circuit breaker, the discharge circuit of the photovoltaic assembly is cut off, and the output current is zero, that is, no current is output. The photovoltaic assembly in the bypass mode is still in the operating state, and constitutes the bypass module 1 and the discharge circuit, but the output voltage is small, and the output voltage depends on the conduction voltage drop of the bypass module. Hereinafter, the off state and the bypass mode of the photovoltaic assembly will be described by comparison respectively. Fig. 3a is a schematic diagram of the state when turning off the photovoltaic assembly using a conventional series-connected circuit breaker. When performing cut-off protection on a single assembly called the photovoltaic (PV) assembly 2 in the photovoltaic array, the discharge circuit of the photovoltaic assembly is cut off, and the current i output by the photovoltaic array PV is = 0. At this time, the photovoltaic array does not operate, and the voltage of the series-connected assembly received by the switch S2 is nV s and Vs is the output voltage when the photovoltaic power generation assembly is blocked.

[0034] Figure 3b is a schematic diagram of a single assembly of an embodiment of the present application in bypass mode. The bypass module in the figure is equivalent to a switch. When bypass protection is required for a photovoltaic power generation assembly with a photovoltaic power generation array, for example, when bypass protection is performed on a single assembly such as photovoltaic (PV) assembly 2, switch S2 is turned on, the bypass module is conducted, and at this time, the current i in bypass switch S2 b is = i s -i MPP where i s is the short-circuit current of photovoltaic (PV) assembly 2, and i MPP is the normal operating current (maximum power point of MPPT) of the photovoltaic power generation array of other series-connected photovoltaic power generation assemblies. Figure 3c is a schematic diagram of all assemblies of an embodiment of the present application in bypass mode. The bypass module in the figure is equivalent to a switch. When bypass protection is required for the assembly of the photovoltaic power generation array, after bypassing all assemblies, switches S1 to S n are turned on, the bypass module is conducted, and at this time, the current i in the bypass switch b is = i s where i PV = 0, and i PV is the output current of the photovoltaic power generation array, and there is no voltage and current output from the photovoltaic power generation array.

[0035] In one possible embodiment, at least one bypass module includes n bypass modules, namely the first bypass module 10, the second bypass module 20... the nth bypass module n10, and at least one photovoltaic assembly includes n photovoltaic assemblies, namely the first photovoltaic assembly PV1, the second photovoltaic assembly PV2... the nth photovoltaic assembly PVn, where n is a natural number greater than 1. Optionally, each bypass module is driven by a corresponding drive circuit, or different bypass modules are driven by the same drive circuit. When at least one photovoltaic assembly includes two or more photovoltaic assemblies, the two or more photovoltaic assemblies may be connected in series or in parallel.

[0036] Optionally, each bypass module is connected in parallel to one corresponding photovoltaic assembly, and can remove the faulty assembly alone without affecting the normal operation of other assemblies, realizing a rapid turn-off of a single assembly. Referring to FIG. 4, the first bypass module 10 is connected in parallel to the first photovoltaic assembly PV1, and the nth bypass module n10 is connected in parallel to the nth photovoltaic assembly PVn. The nth bypass module n10 is driven by the drive circuit n20. The controller 30 can simultaneously control whether to conduct a plurality of bypass modules, and realize a rapid turn-off of a single assembly.

[0037] Optionally, one bypass module is connected in parallel to two or more photovoltaic assemblies, can turn off two or more photovoltaic assemblies simultaneously, and can achieve rapid turn-off of multiple assemblies. Referring to FIG. 5a, the first bypass module 10 is connected in parallel to the first photovoltaic assembly PV1, and the nth bypass module n10 is connected in parallel to two or more photovoltaic assemblies. Alternatively, as shown in FIG. 5b, the first bypass module 10 is connected in parallel to two or more photovoltaic assemblies, and the nth bypass module n10 is also connected in parallel to two or more photovoltaic assemblies. In this embodiment, the power module 40 extracts power from a certain photovoltaic assembly and supplies power to the controller 30 and other modules. The controller 30 can control the bypass protection mechanism of multiple photovoltaic assemblies and reduce costs.

[0038] The control device according to the embodiment of the present application is a complete bypass type control device. In the bypass module connected in parallel to the photovoltaic assembly, there is no switch device between the voltage input terminal 101 and the positive electrode of the photovoltaic assembly, and between the voltage output terminal 102 and the negative electrode of the photovoltaic assembly.

[0039] The operation process of the photovoltaic assembly control device according to the embodiment of the present application is as follows.

[0040] When the photovoltaic assembly operates normally, the controller 30 performs cut-off control on at least one bypass module, and the photovoltaic assembly outputs electrical energy to the outside. The power module 40 obtains electrical energy from the photovoltaic assembly and supplies power to the controller.

[0041] When it is necessary to turn off the solar power generation assembly, the controller 30 controls the conduction of at least one bypass module. The solar power generation assembly connected in parallel to at least one bypass module is bypassed and short-circuit protected. The solar power generation assembly and at least one bypass module form a discharge circuit and do not output electrical energy to the outside. The solar power generation assembly has no safety risk of series connection conduction, meets the safety regulation threshold, and guarantees the power safety of the solar power generation system. The power supply module 40 obtains electrical energy from the bypassed solar power generation assembly and continues to supply power to the controller 30 and the drive circuit 20.

[0042] The embodiment of the present application uses a complete bypass type control device, that is, by directly connecting the bypass module and the solar power generation assembly in parallel, there is no need to serially connect any switch member between the solar power generation assembly and the bypass module. Therefore, the energy consumption caused by the series-connected switch transistor in the series-connected circuit breaker always being conductive is completely avoided, the power consumption is greatly reduced, and the output power of the solar power generation array is increased. Solve the voltage stress problem received when the series-connected switch transistor in the series-connected circuit breaker is first cut off, and improve the safety performance. After removing the series-connected switch transistor, the circuit structure of the control device is simplified, complex off-logic and timing control requirements are avoided, the reliability of the control device is improved, and the cost is reduced. By directly connecting the bypass module and the solar power generation assembly in parallel, the faulty assembly can be removed alone without affecting the normal operation of the string system, and the bypass protection of a single assembly is realized.

[0043] The bypass type rapid control device of the solar power generation assembly of the embodiment of the present application can be applied to solar power generation arrays of different sizes. The bypass protection mechanism has no conduction limit between the serially connected solar power generation assemblies, and the solar power generation of the solar power generation array can be maximized.

[0044] The power module according to the embodiments of the present application can directly extract power from the photovoltaic power generation assembly both in the normal operation and bypass state of the photovoltaic power generation assembly, ensuring the reliability of power supply by the control device, enhancing the reliability of the control device and the stability of the photovoltaic power generation string system, and reducing costs.

[0045] In one possible embodiment, referring to FIG. 6, at least one bypass module 10 includes a power switch member 11, a reverse current protection unit 12, and a voltage drop adjustment unit 13. The input end and the output end of the power switch member 11 are respectively connected to the positive electrode and the negative electrode of the photovoltaic power generation assembly, and the control end 103 of the power switch member 11 is used to receive the drive signal of the drive circuit 20. The drive circuit 20 is controlled by a controller 30. The power switch member 11 bypasses the photovoltaic power generation assembly under the control of the controller 30. The reverse current protection unit 12 is used to prevent the reverse current from damaging the power switch member 11. The voltage drop adjustment unit 13 is used to adjust the voltage drop between the input end and the output end of the bypass module 10 where it is located to a predetermined value when the power switch member 11 is in the operating state (conducting). When the photovoltaic power generation assembly is bypassed and the bypass module is in the operating state, the voltage drop adjustment unit 13 provides an operating voltage to the power module 40 to ensure its normal operation.

[0046] In one possible embodiment, the bypass module 10 includes a first MOS transistor Q1 and at least one diode connected in series with Q1. FIG. 7 shows a situation where three serially connected diodes D4, D5, and D6 are used. The NMOS transistor Q1 is a power switch member 11. The three serially connected diodes D4, D5, and D6 are a reverse current protection unit 12 and a voltage drop adjustment unit 13. The positive and negative output ports of the photovoltaic assembly are connected to the bypass module. The positive electrode PV+ end of the photovoltaic assembly is connected to the three serially connected diodes D4, D5, and D6, serially connected to the power switch transistor Q1. The switch transistor is connected to the assembly port, constituting a controllable bypass one-way short-circuit protection circuit. The anode of D4 is connected to the positive electrode PV+ of the photovoltaic assembly, the cathode of D4 is connected to the anode of D5, the cathode of D5 is connected to the anode of D6. The cathode of D6 is connected to the drain of Q1. The source of Q1 is connected to the negative electrode PV- of the photovoltaic assembly. The gate of Q1 is connected to the drive signal output end of the drive circuit 20.

[0047] Taking FIG. 5 as an example, when a photovoltaic assembly PV1 connected in parallel to the bypass module 10 is connected in series with other photovoltaic assemblies, if PV1 is short-circuited by the bypass module 10, the current output by the other photovoltaic assemblies will flow through the bypass module 10 in the reverse direction, damaging the body diode of Q1. The serially connected diodes can prevent the failure of the original protection diode due to the reverse current flowing through the body diode of the MOS transistor. Also, the serially connected diodes can drop the voltage of the adjustment unit 13, providing an operating voltage to the power module 40 during the operation of the bypass module 10 and ensuring its normal operation. The number of at least one diode is not limited to three and can be determined based on the reverse current it can withstand and the operating voltage required by the power module 40. Optionally, the voltage drop between the input end 101 and the output end 102 of the bypass module 10 can reach 0.9V or more by at least one diode.

[0048] In the embodiment shown in FIG. 7, the power switch member 11 may be further replaced by other power switch devices, such as relays, IGBTs, etc. Q1 is not limited to the NMOS transistor shown in FIG. 7, and a PMOS transistor may be further used. The voltage drop adjustment unit 13 may further use a resistor, and the resistor is connected in series with at least one diode (not shown).

[0049] As shown in FIG. 7, the drive circuit 20 includes a second MOS transistor Q2 and a third transistor Q3. Optionally, Q2 is a P-channel MOS transistor and Q3 is an N-type transistor. The source of Q2 is connected to the second voltage input terminal V2. A first resistor R21 is connected between the gate and the source of Q2. The gate of Q2 is connected to the base of Q3 via a second resistor R22. R21 and R22 are voltage dividing resistors. The drain of Q2 is connected to the negative electrode of the photovoltaic power generation assembly via a third resistor R23 and a fourth resistor R24. The drain of Q2 is connected to the gate of Q1 via a third resistor R23. R18 is the drive signal input resistor of the bypass module 10. The base of Q3 receives the control signal BYPASS_CTL of the controller 30 via a fifth resistor R25. A sixth resistor R26 is connected between the base and the emitter of Q3. R24 and R26 are charge and discharge resistors. The emitter of Q3 is grounded.

[0050] The drive circuit 20 extracts a second voltage V2, such as 5V, from the power module and provides a conduction voltage to Q1. The controller 30 outputs a control signal BYPASS_CTL to control the conduction or cutoff of Q3. When BYPASS_CTL is at a high potential, Q3 is conducted, the potential between R21 and R22 is lower than 5V, Q2 is conducted, R23 and R34 generate a high potential, Q1 is conducted, and the bypass module 10 is conducted. When BYPASS_CTL is at a low potential, Q3 is turned off. When the potential between R21 and R22 is equal to 5V, Q2 is turned off, R23 and R24 are at a low potential, Q1 is turned off, and the bypass module is cut off.

[0051] Referring to FIG. 8, in one possible embodiment, the power supply module 40 includes a buck circuit 41 for converting the voltage output by at least one photovoltaic power generation assembly to a second operating voltage when at least one photovoltaic power generation assembly operates normally, a boost circuit 42 for converting the voltage between the input terminal and the output terminal of at least one bypass module to a first operating voltage when at least one photovoltaic power generation assembly is bypassed, and a switching circuit 43 for comparing the second operating voltage with a reference voltage and controlling whether to conduct the boost circuit 42 and at least one bypass module 10 based on the comparison result. Optionally, the first threshold value is the control voltage BYPASS_CTL output by the controller 30.

[0052] FIG. 9 shows one possible embodiment of the step-down circuit 41. The step-down circuit 41 includes a first integrated chip U1 having six pins 411 to 416. Pin 411 is connected as a voltage input terminal to the positive electrode PV+ of the solar power generation assembly. Pin 411 is connected to the negative electrode PV- of the solar power generation assembly via a first capacitor C1. C1 serves as an input voltage stabilizing capacitor, performing the functions of filtering and voltage stabilization. A seventh resistor R411 and an eighth resistor R412 are connected in series between pin 411 and ground. Pin 414 is connected between R411 and R412. R411 and R412 are voltage-dividing resistors connected in series, providing an enable signal to the port of chip 414 to control the operating state of the chip. The chip operates when the enable signal is at a high potential and does not operate when the enable signal is at a low potential. Pin 415 is connected to PV-. A second capacitor C2 is connected in series between pin 412 and pin 413, serving as a bootstrap capacitor to provide a driving voltage for driving the power switch transistor within the chip. Pin 413 is the U1 voltage output terminal. To stabilize the voltage of the output port, a first voltage stabilizing diode DZ1 is connected between it and ground. Pin 413 is further grounded via a first inductor L1 and a third capacitor C3 connected in series with each other. L1 and C3 form an LC filtering structure to filter out harmonics and stabilize the second voltage V2 of the output DC voltage. The output terminal of the second voltage V2 is grounded via a ninth resistor R414 and a tenth resistor R413 connected in series. Pin 416 is connected between R414 and R413 and is used to perform voltage sampling on the output V2 to form a feedback signal and transmit it to the chip U1.

[0053] In order to stabilize the voltage V2 output by the buck circuit 41, the output terminal of the second voltage V2 is connected to the eighth diode D8 to form a one-way charge type clamp voltage stabilization circuit, and a stable first voltage V1 is obtained. V1 constitutes a one-way discharge circuit by the eleventh resistor R415 and the light-emitting diode D9 connected in series to prevent overvoltage of the output power supply. D9 emits light, and V1 has a certain amount of electrical energy. A fourth capacitor C4 is further connected between V1 and the ground to filter and stabilize the first voltage V1.

[0054] FIG. 10 shows one possible embodiment of the boost circuit 42. The boost circuit 42 includes a second integrated chip U2 including six pins 421 to 426. Pin 423 is the voltage input terminal of U2. Pin 421 is connected to pin 423 via a second inductance. L2 is a boost inductance, which is used to store electrical energy and increase the voltage. Pin 423 is further grounded via a second voltage stabilizing diode DZ2 and a fifth capacitor C5 connected in parallel. C5 is a voltage stabilizing capacitor. Pin 424 is the U2 enable terminal and is connected to the voltage input terminal pin 423 via a twelfth resistor R421. R421 is an enable input resistor, which controls the input magnitude of the enable signal. Pin 425 is grounded. Pin 422 is the voltage output terminal and is grounded via a sixth capacitor C6. C6 is used to fit the interference waveform and stabilize the DC output. Pin 422 is further grounded via a fourteenth resistor R423 and a thirteenth resistor R422 connected in series. Pin 426 is connected between R423 and R422 and is used to sample the output voltage and form a feedback signal to transmit to the chip U2. In order to stabilize the first voltage V1 output by the boost circuit 42, the voltage output pin 422 of U2 is connected to the tenth diode D10 to obtain a stable first voltage V1.

[0055] In one possible embodiment, the switching circuit 43 includes a comparator and at least one switch transistor. The first signal input terminal of the comparator is used to receive the second operating voltage output by the buck circuit, and the second signal input terminal of the comparator is used to receive a reference signal. The input terminal and the output terminal of at least one switch transistor are connected to the boost circuit and the bypass module. The control terminal of at least one switch transistor is connected to the signal output terminal of the comparator. At least one switch transistor conducts and controls the boost circuit and the bypass module based on the output signal of the comparator. Since the bypass module is connected in parallel with the photovoltaic power generation assembly, when the boost circuit and the bypass module are conducted, the photovoltaic power generation assembly is conducted. Referring to FIGS. 8 and 10, the switching circuit 43 includes a comparator U3 and a fourth transistor Q4. The first signal input terminal of U3 is used to receive the second operating voltage V2 output by the buck circuit U1. The second signal input terminal of U3 is used to receive a reference voltage signal. Optionally, the reference voltage signal is the control signal BYPASS_CTL output by the controller 30. The fourth transistor Q4 is connected to the boost circuit 42 and the bypass module 10. The signal output terminal of the comparator U3 is used to control whether to conduct Q4 and thus control whether to conduct the boost circuit 42 and the bypass module 10. The emitter of Q4 in FIG. 10 is connected to the positive electrode PV+ of the photovoltaic power generation assembly, and PV+ and the input terminal 101 of the bypass module 10 are at the same potential. Therefore, the emitter of Q4 is simultaneously connected to the bypass module 10.

[0056] The switching circuit 43 further includes a fifth transistor Q5. U3 uses a constant current comparator. The inverting input terminal of U3 is connected to the second voltage V2 via a fifteenth resistor R431. R431 is an input resistor and controls the reference of the input current. The output terminal of U3 is connected to the base of Q5 via a sixteenth resistor R433. The output terminal of U3 is grounded via a sixteenth resistor R433 and a seventeenth resistor R434 connected in series. R434 is a charge and discharge resistor and is connected in series between the base and the emitter of the transistor Q5. A fourteenth resistor R432 and a nineteenth resistor R435 connected in series with each other are connected between the positive electrode of the photovoltaic assembly and the collector electrode of Q5. R432 and R435 are voltage dividing resistors. R432 is connected between the collector electrode and the base of Q4. R435 is connected between the base of Q4 and the collector electrode of Q5. Optionally, Q4 is a P-channel transistor and Q5 is an N-channel transistor. The collector electrode of Q4 is connected to the voltage input terminal 423 of U2 as the voltage output terminal of the switching circuit 43.

[0057] The operating principle of the power supply module 40 is as follows. The power supply module is divided into two power extraction states: the normal operation of the photovoltaic assembly and the bypass conduction. When the bypass module is cut off, the photovoltaic assembly operates normally and outputs electrical energy to the outside. The output voltage is, for example, 17 - 60V. At this time, the buck circuit 41 operates to reduce the voltage output by the photovoltaic assembly and convert it to the second voltage V2. By further reducing the internal voltage and outputting the first voltage V1, it stably supplies power to the controller 30. When the bypass module 10 is conducted, the reverse current protection unit 12 forms a one-way conduction bypass, and the voltage drop adjustment unit forms a predetermined voltage drop to ensure the normal operation of the boost circuit. At this time, the boost circuit 42 converts the voltages at the input and output ends of the bypass module 10 to the first voltage V1 and stably supplies power to the controller 30. To prevent the input of the boost circuit 43 from exceeding the allowable range, the buck-boost switching circuit 43 compares whether the voltage output by the buck circuit reaches the allowable range. When the voltage output by the buck circuit reaches the allowable range and is, for example, less than 3.3V, the boost circuit 42 and the bypass module 41 are conducted. Since the bypass module 41 bypasses the photovoltaic assembly, the voltage output by the photovoltaic assembly is the voltage between the input and output ends of the bypass module 41, and the boost circuit 42 boosts this voltage to obtain a stable first voltage.

[0058] The power supply module of this application realizes the extraction of low-voltage DC power through bypass, solves the problem of extracting low-voltage DC power in the bypass mode, provides a stable auxiliary power supply for the control device, ensures the stable operation of the photovoltaic array, and makes the power generation of the photovoltaic system safe and efficient.

[0059] Referring to FIGS. 8 and 10, in one possible embodiment of the present application, the power module 40 further includes a voltage regulator 44 including a fourth chip U4. The fourth chip U4 is used to achieve DC voltage conversion and convert the first voltage V1 into the voltage V0 required by the controller. V0 is, for example, 3V. U4 includes pins 441 to 445. Optionally, U4 is a linear voltage stabilization chip. Pin 441 is a voltage input terminal and is used to receive the first voltage V1. Pin 441 is grounded via the seventh capacitor C7. C3 is an input filtering capacitor and is used to stabilize the input power supply. Pin 442 is an enable terminal and is connected to pin 441 to receive the first voltage V1. Pin 443 is grounded. Pin 445 is a voltage output terminal and is grounded via the eighth capacitor C8. C8 is used to stabilize the output DC power supply.

[0060] In one possible embodiment of the present application, the controller further includes a voltage detection circuit 60 and a temperature detection circuit 70 to monitor the operating state of the solar power generation assembly. The voltage detection circuit 60 is used to obtain the voltage output by at least one solar power generation assembly, and the temperature detection circuit 70 is used to obtain the temperature of at least one solar power generation assembly. When the solar power generation assembly generates electricity, the illuminance and the temperature of the battery panel affect the current of the battery panel. Within a certain range, the stronger the light irradiation, the larger the output current, and the higher the temperature, the smaller the output voltage. When the solar power generation assembly fails, the solar power generation curve voltage is small. By using the voltage detection circuit 60, it is possible to determine whether there is a failure and transmit a detection signal to the controller 30. In case of failure, the controller 30 controls the bypass module to conduct in one direction, thereby protecting the solar power generation assembly and stabilizing the string system. By using the voltage detection circuit 60 and the temperature detection circuit 70, the state monitoring of a single assembly is realized, and the protection of the solar power generation assembly becomes more accurate.

[0061] Optionally, the photovoltaic assembly control device further includes a communication module 50 for receiving a control signal and transmitting the control signal to the controller 30. Optionally, the communication module and the controller control module are packaged in one chip. When it is necessary to actively turn off the photovoltaic assembly, for example, in the case of a special situation such as a house fire, the controller 30 receives a remote control signal via the communication module 50, controls the drive circuit 20 to conduct the bypass module 10, and realizes the bypass short-circuit protection of the photovoltaic assembly. Optionally, the communication module 50 is a short-distance communication module or a remote communication module. The short-distance communication module includes a Bluetooth (registered trademark) module, a WIFI module, a ZigBee module, an Ethernet module, a serial module, a Centronics module, etc. The remote communication module includes a GPRS module, a 2G module, a 3G module, a 4G module, a 5G module, an LTE module, etc.

[0062] Optionally, as shown in FIG. 8, the photovoltaic assembly control device and the bypass diodes (D1, D2, and D3) of the battery sheet of the photovoltaic assembly are packaged, for example, installed in the same wiring box.

[0063] Optionally, the power supply module 40 further supplies power to the communication module 50, the voltage detection circuit 60, and the temperature detection circuit 70.

[0064] FIG. 12 shows a photovoltaic array using a single - control - type photovoltaic assembly control device. The photovoltaic array is composed of a plurality of photovoltaic assemblies connected in series - parallel. According to the coordinate arrangement method, the positions and marks of n×m assemblies can be obtained. Each photovoltaic assembly is connected to a bypass - type rapid control device. When an accident occurs in a photovoltaic assembly, the bypass module connected in parallel to the photovoltaic assembly is rapidly turned on, short - circuit - protecting the assembly and ensuring the safety of the power system. The single - control - type photovoltaic assembly control device can realize the state monitoring of a single assembly.

[0065] FIG. 13 shows a photovoltaic array using a multi - control - type photovoltaic assembly control device. This photovoltaic array uses a plurality of assemblies of bypass - type rapid cut - off switches of photovoltaic assemblies to extract power from a single photovoltaic assembly and supply power to the controller 30 and other modules. The controller 30 can realize the bypass protection mechanism of a plurality of photovoltaic assemblies and can reduce costs.

[0066] For the sake of brevity of description, the above - described technical features of each embodiment do not cover all possible combinations of the technical features in the above - described embodiments. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0067] The above - described embodiments only represent some embodiments of this application. The description is more specific and detailed, but it cannot be understood as a limitation of the patent scope. It should be pointed out that those skilled in the art can make some modifications and improvements without departing from the spirit of this application, and these belong to the protection scope of this application. Therefore, the protection scope of the patent of this application shall be subject to the scope of the appended patent claims.

Claims

Claim 1 A photovoltaic power generation assembly control device, comprising at least one bypass module, a drive circuit, a power supply module, and a controller, wherein the at least one bypass module is used to be connected in parallel with at least one photovoltaic power generation assembly, and the power supply module is used to be connected to the at least one photovoltaic power generation assembly and the at least one bypass module, the at least one bypass module is used to bypass the at least one photovoltaic power generation assembly under the control of the controller, the drive circuit is used to drive the at least one bypass module to operate under the control of the controller, the power supply module is used to obtain electrical energy from the at least one photovoltaic power generation assembly when the at least one photovoltaic power generation assembly operates normally and when the at least one photovoltaic power generation assembly is bypassed, and output the electrical energy to the controller and the drive circuit, the controller is used to control the conduction state of the at least one bypass module to control whether the at least one photovoltaic power generation assembly is in a bypass mode, the power supply module, when the at least one photovoltaic power generation assembly operates normally, a buck circuit for converting the voltage output by the at least one photovoltaic power generation assembly into a second operating voltage, when the at least one photovoltaic power generation assembly is bypassed, a boost circuit for converting the voltage between the input terminal and the output terminal of the at least one bypass module into a first operating voltage, a switching circuit for comparing the second operating voltage with a reference voltage and controlling whether to conduct the boost circuit and the at least one bypass module based on the comparison result. A photovoltaic power generation assembly control device is characterized by the above. Claim 2 The at least one bypass module includes a power switch member, an input end and an output end of the power switch member are respectively connected to a positive electrode and a negative electrode of the at least one solar power generation assembly, and a control end of the power switch member is used for receiving a driving signal of the driving circuit. The solar power generation assembly control device according to claim 1, characterized in that.

3. The at least one bypass module further includes a reverse current protection unit connected in series to the power switch member to prevent the reverse current from damaging the power switch member. The solar power generation assembly control device according to claim 2, characterized in that.

4. The at least one bypass module further includes a voltage drop adjustment unit for adjusting a voltage drop between an input end and an output end of the at least one bypass module to a predetermined value when the power switch member is in an operating state. The solar power generation assembly control device according to claim 2, characterized in that.

5. The at least one bypass module further includes at least one diode connected in series to the power switch member. The solar power generation assembly control device according to claim 2, characterized in that.

6. The switching circuit includes a comparator and at least one switch transistor. A first signal input end of the comparator is used for receiving the second operating voltage output by the buck circuit, a second signal input end of the comparator is used for receiving a reference signal, an input end and an output end of the at least one switch transistor are connected to the boost circuit and the at least one bypass module, and a control end of the at least one switch transistor is connected to a signal output end of the comparator. The solar power generation assembly control device according to claim 1, characterized in that.

7. The at least one bypass module includes two or more bypass modules connected in series with each other, and the two or more bypass modules connected in series with each other are used for being connected in parallel to the at least one solar power generation assembly. The solar power generation assembly control device according to claim 6, characterized in that.

8. The controller further includes a communication module, a voltage detection circuit, and / or a temperature detection circuit, The communication module is used to receive a control signal and transmit the control signal to the controller, The voltage detection circuit is used to obtain the voltage output by the at least one solar power generation assembly, The temperature detection circuit is used to obtain the temperature of the at least one solar power generation assembly, The solar power generation assembly control device according to claim 1, characterized in that.

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