Photovoltaic module control device

Abstract

The embodiment of the invention provides a photovoltaic module control device, and the device comprises at least one bypass module which is used for being connected with at least one photovoltaic module in parallel; the driving circuit is used for driving at least one bypass module to work under the control of the controller; the power supply module is used for obtaining electric energy from the at least one photovoltaic module and outputting the electric energy to the controller under the condition that the at least one photovoltaic module works normally and the at least one photovoltaic module is bypassed; and the controller is used for controlling the conduction state of the at least one bypass module so as to control whether the at least one photovoltaic module is in the bypass mode or not. The power consumption of the control device is greatly reduced, meanwhile, the problem of voltage stress borne by the first series switch tube in the series control device when the first series switch tube is disconnected is solved, and the safety performance of the bypass control device is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a photovoltaic component control device. Background Art

[0002] Photovoltaic power generation technology is one of the most widely used clean energy technologies. The photovoltaic inverter grid-connected power system consists of a photovoltaic array and an inverter system. The photovoltaic array consists of multiple photovoltaic modules connected in series to provide sufficient and stable power for the photovoltaic system. The photovoltaic module is a packaged, smallest indivisible photovoltaic cell combination device that can provide direct current output independently, also known as a solar cell module or solar panel. The photovoltaic module consists of multiple cell units and their parallel reverse protection diodes. The fast control device is a commonly used protection mechanism in photovoltaic systems.

[0003] The traditional control device is a series control device, that is, there are series switches in the voltage output circuit of the photovoltaic module. When the photovoltaic system is generating electricity normally, the series switch is in a normally on state to ensure the series connection of the modules and the normal operation of the photovoltaic system. When there is a safety problem or a safety fault in the system, the series switch is disconnected, disconnecting the series photovoltaic array, so that the voltage at any interface of the array meets the safety limit, protecting the safety of the inverter system.

[0004] The above-mentioned series control device has a major defect. When the series switch tube is in a normally closed state, a large amount of switch tube conduction energy consumption will be generated, resulting in low power generation efficiency. Summary of the invention

[0005] In view of this, an embodiment of the present application provides a photovoltaic assembly control device to solve at least one problem existing in the background technology.

[0006] In a first aspect, an embodiment of the present application provides a photovoltaic assembly control device, comprising: at least one bypass module, a drive circuit, a power module and a controller; the at least one bypass module is used to be connected in parallel with at least one photovoltaic assembly; the power module is used to be connected with the at least one photovoltaic assembly and the at least one bypass module;

[0007] The at least one bypass module is used to bypass the at least one photovoltaic assembly under the control of the controller;

[0008] The driving circuit is used to drive the at least one bypass module to work under the control of the controller;

[0009] The power module is used to obtain electric energy from the at least one photovoltaic component and output the electric energy to the controller when the at least one photovoltaic component is operating normally and when the at least one photovoltaic component is bypassed;

[0010] The controller is used to control the conduction state of the drive circuit and the at least one bypass module to control whether the at least one photovoltaic component is in a bypass mode.

[0011] In combination with the first aspect of the present application, in an optional embodiment, the at least one bypass module includes a power switch device, the input end and the output end of the power switch device are respectively connected to the positive pole and the negative pole of the at least one photovoltaic component, and the control end of the power switch device is used to receive the driving signal of the driving circuit.

[0012] In combination with the first aspect of the present application, in an optional implementation manner, the at least one bypass module further includes: a reverse current protection unit, connected in series with the power switch component, for preventing a reverse current from damaging the power switch component.

[0013] In combination with the first aspect of the present application, in an optional embodiment, the at least one bypass module also includes: a voltage drop adjustment unit, which is used to adjust the voltage drop between the input and output ends of the at least one bypass module to a predetermined value when the power switch component is in a working state.

[0014] In combination with the first aspect of the present application, in an optional implementation manner, the at least one bypass module further includes: at least one diode, and the at least one diode is connected in series with the power switch component.

[0015] In combination with the first aspect of the present application, in an optional implementation, the power module includes: a step-down circuit, configured to convert a voltage output by the at least one photovoltaic component into a second operating voltage when the at least one photovoltaic component operates normally.

[0016] In combination with the first aspect of the present application, in an optional embodiment, the power module includes: a boost circuit for converting the voltage between the input and output ends of the at least one bypass module into a first operating voltage when the at least one photovoltaic component is bypassed.

[0017] In combination with the first aspect of the present application, in an optional embodiment, the power supply module includes: a switching circuit for comparing the second operating voltage with a reference voltage, and controlling whether the boost circuit and the at least one bypass module are connected according to the comparison result.

[0018] In combination with the first aspect of the present application, in an optional embodiment, the switching circuit includes a comparator and at least one switching tube, the first signal input end of the comparator is used to receive the second operating voltage output by the step-down circuit, and the second signal input end of the comparator is used to receive a reference signal; the input end and the output end of the at least one switching tube are connected to the boost circuit and the bypass module; and the control end of the at least one switching tube is connected to the signal output end of the comparator.

[0019] In combination with the first aspect of the present application, in an optional implementation, the at least one bypass module includes two or more bypass modules connected in series, and the two or more bypass modules connected in series are used to be connected in parallel with at least one photovoltaic component.

[0020] In conjunction with the first aspect of the present application, in an optional implementation manner, the controller further includes: a communication module, a voltage detection circuit and / or a temperature detection circuit;

[0021] The communication module is used to receive a control signal and transmit the control signal to the controller;

[0022] The voltage detection circuit is used to obtain the voltage output by at least one photovoltaic component;

[0023] The temperature detection circuit is used to obtain the temperature of at least one photovoltaic component.

[0024] The photovoltaic module control device provided in the embodiment of the present application, by directly connecting the bypass module in parallel with the photovoltaic module, puts it in bypass mode when the photovoltaic module does not need to output normal working voltage or working power, and does not need to connect any switch in series between the photovoltaic module and the bypass module, thereby completely avoiding the energy consumption caused by the series switch tube in the traditional series type circuit breaker being normally turned on, greatly reducing the power consumption of the control device, and improving the output power of the photovoltaic matrix. At the same time, it solves the problem of voltage stress when the first series switch tube in the series type circuit breaker is disconnected, and improves the safety performance. After canceling the series switch tube, the circuit structure of the control device is simplified, the complex shutdown 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 in parallel with the photovoltaic module, the faulty component can be removed individually without affecting the normal operation of the string system, and the single component shutdown is achieved.

[0025] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0027] Figure 1 It is a schematic diagram of a series photovoltaic shut-off device in the related art;

[0028] Figure 2 Schematic diagram of a photovoltaic module control device provided in an embodiment of the present application Figure 1 ;

[0029] Figure 3a A schematic diagram of using a series photovoltaic disconnector to shut down a photovoltaic module;

[0030] Figure 3b A schematic diagram of a photovoltaic module bypassing a single module using the photovoltaic module control device according to an embodiment of the present application;

[0031] Figure 3c A schematic diagram of using the photovoltaic module control device according to an embodiment of the present application to bypass the entire photovoltaic module;

[0032] Figure 4 Schematic diagram of a photovoltaic module control device provided in an embodiment of the present application Figure 2 ;

[0033] Figure 5a Schematic diagram 3 of a photovoltaic assembly control device provided in one embodiment of the present application;

[0034] Figure 5b Schematic diagram of a photovoltaic module control device provided in an embodiment of the present application Figure 4 ;

[0035] Figure 6 A schematic diagram of a bypass module provided in an embodiment of the present application Figure 1 ;

[0036] Figure 7 A schematic diagram of a bypass module and a driving circuit provided in an embodiment of the present application;

[0037] Figure 8 Schematic diagram of a photovoltaic module control device provided in an embodiment of the present application Figure 6 ;

[0038] Fig. 9 A schematic diagram of a step-down circuit provided in an embodiment of the present application;

[0039] Fig.10 A schematic diagram of a boost circuit and a switching circuit provided in an embodiment of the present application;

[0040] Fig.11A voltage regulator provided in an embodiment of the present application;

[0041] Fig.12 A schematic diagram of a single-control photovoltaic module control device provided in one embodiment of the present application;

[0042] Fig.13 A schematic diagram of a multi-control photovoltaic assembly control device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the technical solutions and beneficial effects of the present application more obvious and understandable, the technical solutions in the embodiments of the present application are clearly and completely described below by listing specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0045] It is understood that the terms "first", "second", etc. used in this application can be used to describe various elements in this article, but these elements are not limited by 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 referred to as the second resistor, and similarly, the second resistor can be referred to as the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor. When describing "first", it does not mean that there must be a "second"; and when discussing "second", it does not mean that there must be a first element, component, area, layer or part in this application. When used here, the singular forms of "one", "one" and "said / the" may also be intended to include plural forms, unless the context clearly indicates otherwise. The meaning of "multiple" is more than two, unless otherwise clearly and specifically defined. It should also be understood that the term "including", when used in this specification, determines the presence of the features, but does not exclude the presence or addition of one or more other features. When used here, the term "and / or" includes any and all combinations of the relevant listed items.

[0046] It can be understood that in the context of this application, "connection" means that there is mutual transmission of electrical signals or data between the connected end and the connected end, which can be understood as "electrical connection", "communication connection", etc. In the context of this application, "A is directly connected to B" means that there are no other components between A and B except wires.

[0047] Figure 1 The relevant technology of the photovoltaic control device is shown. The photovoltaic array includes n photovoltaic modules connected in series. The photovoltaic array outputs electric energy through the positive voltage output terminal 1 and the negative voltage output terminal 2. A switch is connected in series in the voltage output circuit of each photovoltaic module, and a switch is connected in parallel to the voltage output terminal of each photovoltaic module. The voltage output circuit of photovoltaic module 1 is connected in series with switch S1, and the voltage output terminal of photovoltaic module 1 after the switch is connected in series is connected with an anti-reverse diode D1 in parallel; the voltage output terminal of photovoltaic module 2 is connected in series with switch S2, and the voltage output terminal of photovoltaic module 2 after the switch S2 is connected in series is connected with an anti-reverse diode D2 in parallel; the voltage output terminal of photovoltaic module n is connected in series with switch Sn, and the voltage output terminal of photovoltaic module 3 after the switch Sn is connected in series is connected with an anti-reverse diode Dn in parallel. The voltage output circuit of photovoltaic module 1 is connected with a power supply circuit for providing electric energy to the control circuit so that it can work continuously.

[0048] When a PV module is detected to have a fault or a potential safety hazard, the switch connected in series with the PV module is disconnected, for example, S1 is disconnected to shut down the output of the PV module, and the current output by other PV modules will flow through D1.

[0049] The inventors have discovered that the above-mentioned series-type control device has the following defects: First, when the photovoltaic module is working normally, the series switch tubes are often turned on, and these turned-on switch tubes will generate a large amount of energy consumption. Second, the series control device has high requirements for shutdown logic and timing control, and the complex control system leads to high cost of the control device. Third, when the first switch tube in the control device is disconnected, it needs to withstand the high voltage stress of the photovoltaic string system, and there is a risk of overvoltage breakdown. Fourth, how to provide a stable and reliable power supply circuit when the photovoltaic module is in the above-mentioned normal working and shut-down different working states is also an important problem that the field has been committed to solving.

[0050] To this end, an embodiment of the present application provides a photovoltaic component control device, including: at least one bypass module 10, a drive circuit 20, a power module 40 and a controller 30. At least one bypass module 10 is used to be connected in parallel with at least one photovoltaic component, and to bypass at least one photovoltaic component connected in parallel therewith under the control of the controller 30. When at least one photovoltaic component is bypassed, it is in bypass mode. At least one bypass module can be one bypass module or more than two bypass modules. At least one photovoltaic component can be one photovoltaic component or more than two photovoltaic components. At least one bypass module is used to be connected in parallel with at least one photovoltaic component, and it can be one bypass module connected in parallel with one photovoltaic component; or one bypass module connected in parallel with two or more photovoltaic components; or two or more bypass modules are connected in series with each other and then connected in parallel with one or more photovoltaic components.

[0051] Figure 2The embodiment of a bypass module 10 connected in parallel with a photovoltaic module is shown. The photovoltaic module includes a plurality of cell units, each of which is connected in reverse parallel with a diode. Figure 2 As shown, D1, D2 and D3 are diodes connected in reverse parallel with the photovoltaic cell unit inside the photovoltaic module PV, forming a unidirectional channel for the module power supply.

[0052] The bypass module 10 is used to be connected in parallel with a photovoltaic module 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 and negative poles of PV1, and there is no switching device between the voltage input terminal 101 and the positive pole of at least one photovoltaic module PV1, and between the voltage output terminal 102 and the negative pole 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.

[0053] The power module 40 is used to connect with at least one photovoltaic module PV1 and at least one bypass module 10, and obtain electric energy from at least one photovoltaic module PV1 when at least one photovoltaic module PV1 is working normally and when at least one photovoltaic module PV1 is bypassed, and output the electric energy to the controller 30 and the drive circuit 20. The power module 40 can obtain electric energy in both the normal working mode and the bypass mode of the photovoltaic module, and supply power to the controller 30 and the drive circuit 20 to enable them to work continuously.

[0054] The driving circuit 20 receives a control signal from the controller 30 and outputs a driving voltage to at least one bypass module 10 to drive the bypass module 10 to work under the control of the controller 30. The driving circuit 20 also obtains a working voltage from the power module 40.

[0055] 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 bypass mode. When at least one photovoltaic assembly PV1 needs to be bypassed, the controller 30 outputs a control signal to the drive circuit 20, and the drive circuit 20 then drives the bypass module 10 to conduct, bypassing at least one photovoltaic assembly PV1, so that it is in bypass mode and stops outputting electrical energy. Situations in which at least one photovoltaic assembly PV1 needs to be bypassed include power system failures or safety accidents, such as: DC arcs in photovoltaic assemblies, failures in photovoltaic assemblies, fires, etc.

[0056] When the PV module is turned off by a traditional series disconnector, the discharge circuit of the PV module is disconnected and the output current is zero, that is, no current is output. The PV module in bypass mode is still in operation and forms a discharge circuit with the bypass module 1, but the output voltage is very small, and the output voltage depends on the conduction voltage drop of the bypass module. The shutdown state and bypass mode of the PV module are compared and explained below. Figure 3a The schematic diagram is a state diagram of the photovoltaic module being shut down by a traditional series circuit breaker. When the photovoltaic (PV) module 2 is disconnected in the photovoltaic array, the discharge circuit of the photovoltaic module is disconnected, and the current i output by the photovoltaic array is PV =0, the photovoltaic array is not working, and the voltage of the series components on switch S2 is nV s , V s This is the output voltage when the PV module is disconnected.

[0057] Figure 3b This is a schematic diagram of a single-component bypass mode of an embodiment of the present application. In the figure, the bypass module is equivalent to a switch. When a photovoltaic component of the photovoltaic array needs bypass protection, for example, single-component bypass protection is performed on photovoltaic (PV) component 2, switch S2 is closed and the bypass module is turned on. At this time, the current on bypass switch S2 is i b =i s -i MPP ,i s is the short-circuit current of photovoltaic (PV) module 2, i MPP It is the normal operating current of the photovoltaic array of the remaining series-connected photovoltaic modules (MPPT maximum power point). Figure 3c Schematic diagram of the full-component bypass mode of the embodiment of the present application, in which the bypass module is equivalent to a switch. When the components of the photovoltaic array need bypass protection, all components are bypassed, and switches S1 to S n Closed, the bypass module is turned on, and the current on the bypass switch is i b =i s ,i PV =0,i PV The photovoltaic array outputs current, and the photovoltaic array has no voltage and current output.

[0058] In a possible implementation, at least one bypass module includes n bypass modules, a first bypass module 10, a second bypass module 20, ... an nth bypass module n10; at least one photovoltaic assembly includes n photovoltaic assemblies, a first photovoltaic assembly PV1, a second photovoltaic assembly PV2, ... an nth photovoltaic assembly PVn; n is a natural number greater than one. 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 more than two photovoltaic assemblies, the more than two photovoltaic assemblies can be connected in series or in parallel.

[0059] Optionally, each bypass module is connected in parallel with a PV module, which can cut off the faulty module individually without affecting the normal operation of other modules, thus realizing the rapid shutdown of a single module. Figure 4 The first bypass module 10 is connected in parallel with the first photovoltaic module PV1, and the nth bypass module n10 is connected in parallel with the nth photovoltaic module PVn. The nth bypass module n10 is driven by the driving circuit n20. The controller 30 can simultaneously control the conduction of multiple bypass modules, thereby realizing the rapid shutdown of a single component.

[0060] Optionally, a bypass module is connected in parallel with more than two PV modules, which can shut down more than two PV modules at the same time, thus realizing the rapid shutdown of multiple modules. Figure 5a , the first bypass module 10 is connected in parallel with the first photovoltaic module PV1, and the nth bypass module n10 is connected in parallel with two or more photovoltaic modules. Figure 5b As shown, the first bypass module 10 is connected in parallel with more than two photovoltaic modules, and the nth bypass module n10 is also connected in parallel with more than two photovoltaic modules. In this embodiment, the power module 40 draws power from a photovoltaic module to power the controller 30 and other modules. The controller 30 can control the bypass protection mechanism of multiple photovoltaic modules to reduce costs.

[0061] The control device of the embodiment of the present application is a pure bypass type control device. In the bypass module connected in parallel with the photovoltaic component, there is no switching device between the voltage input terminal 101 and the positive pole of the photovoltaic component, and between the voltage output terminal 102 and the negative pole of the photovoltaic component.

[0062] The working process of the photovoltaic module control device of the embodiment of the present application is as follows:

[0063] When the photovoltaic assembly works normally, the controller 30 controls at least one bypass module to be disconnected, and the photovoltaic assembly outputs electric energy. The power module 40 obtains electric energy from the photovoltaic assembly and supplies power to the controller.

[0064] When the photovoltaic module needs to be turned off, the controller 30 controls at least one bypass module to be turned on, and the photovoltaic module connected in parallel with at least one bypass module is bypassed and short-circuited. The photovoltaic module and at least one bypass module form a discharge loop without outputting electrical energy. The photovoltaic module has no safety hazard of series conduction, meets the safety limit, and ensures the power safety of the photovoltaic system. The power module 40 obtains electrical energy from the bypassed photovoltaic module and continuously supplies power to the controller 30 and the drive circuit 20.

[0065] The embodiment of the present application adopts a pure bypass type control device, that is, the bypass module is directly connected in parallel with the photovoltaic module, and there is no need to connect any switch in series between the photovoltaic module and the bypass module, thereby completely avoiding the energy consumption caused by the series switch tube in the series type circuit breaker being normally turned on, greatly reducing power consumption and improving the output power of the photovoltaic array. The voltage stress problem that the first series switch tube in the series type circuit breaker is borne when it is disconnected is solved, and the safety performance is improved. After the series switch tube is cancelled, the circuit structure of the control device is simplified, the complex shutdown 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 in parallel with the photovoltaic module, the faulty component can be removed individually without affecting the normal operation of the string system, thereby realizing single component bypass protection.

[0066] The photovoltaic component bypass-type rapid control device of the embodiment of the present application can be applied to photovoltaic arrays of different sizes. The bypass protection mechanism eliminates conduction constraints between photovoltaic components connected in series, thereby maximizing the power generation of the photovoltaic array.

[0067] The power module provided in the embodiment of the present application can directly draw power from the photovoltaic components both when the photovoltaic components are in normal working state and in bypass state, thereby ensuring the reliability of the power supply of the control device, improving the reliability of the control device and the stability of the photovoltaic string system, and reducing costs.

[0068] In one possible implementation, reference Figure 6 , at least one bypass module 10 includes a power switch 11, a reverse current protection unit 12 and a voltage drop regulating unit 13. The input and output ends of the power switch 11 are respectively connected to the positive and negative poles of the photovoltaic module, and the control end 103 of the power switch 11 is used to receive the drive signal of the drive circuit 20. The drive circuit 20 is controlled by the controller 30. Under the control of the controller 30, the power switch 11 bypasses the photovoltaic module. The reverse current protection unit 12 is used to prevent the reverse current from damaging the power switch 11. The voltage drop regulating unit 13 is used to adjust the voltage drop between the input and output ends of the bypass module 10 to a predetermined value when the power switch 11 is in a working state (conducting). When the photovoltaic module is bypassed and the bypass module is in a working state, the voltage drop regulating unit 13 provides a working voltage for the power module 40 to ensure its normal operation.

[0069] In a possible implementation, the bypass module 10 includes a first MOS transistor Q1 and at least one diode connected in series with Q1. Figure 7The case of using three series diodes D4, D5 and D6 is shown in the figure. Among them, the NMOS tube Q1 is used as the power switch element 11. The three series diodes D4, D5 and D6 are also used as the reverse current protection unit 12 and the voltage drop adjustment unit 13. The positive and negative output ports of the photovoltaic component are connected to the bypass module. The positive pole PV+ of the photovoltaic component is connected to three series diodes D4, D5 and D6, and then connected in series to the power switch tube Q1. The switch tube is connected to the component port to form a controllable bypass unidirectional short-circuit protection circuit. The anode of D4 is connected to the positive pole PV+ of the photovoltaic component, the cathode of D4 is connected to the anode of D5, and 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 pole PV- of the photovoltaic component. The gate of Q1 is connected to the drive signal output end of the drive circuit 20.

[0070] Taking Figure 5 as an example, when the photovoltaic module PV1 connected in parallel with the bypass module 10 is connected in series with other photovoltaic modules, if PV1 is short-circuited by the bypass module 10, the current output by other photovoltaic modules will flow in reverse through the bypass module 10, causing damage to the body diode of Q1. By connecting the diodes in series, it is possible to prevent the reverse current from passing through the body diode of the MOS tube and causing the original protection diode to fail. In addition, the diodes connected in series can be a voltage drop adjustment unit 13, which provides a working voltage for the power module 40 when the bypass module 10 is working, ensuring its normal operation. The number of at least one diode is not limited to three, and can be determined according to the reverse current it can withstand and the working voltage required by the power module 40. Optionally, at least one diode makes the voltage drop between the input terminal 101 and the output terminal 102 of the bypass module 10 reach 0.9V or more.

[0071] Figure 7 In the embodiment shown, the power switch 11 may also be replaced by other power switch devices, such as relays, IGBTs, etc. Figure 7 The NMOS transistor shown in the figure may also be a PMOS transistor. The voltage drop adjustment unit 13 may also be a resistor, which is connected in series with at least one diode (not shown in the figure).

[0072] like Figure 7As shown, the driving circuit 20 includes: a second MOS tube Q2, and a third transistor Q3. Optionally, Q2 is a P-channel MOS tube; 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 source of Q2. The gate of Q2 is connected to the base of Q3 through a second resistor R22. R21 and R22 are voltage-dividing resistors. The drain of Q2 is connected to the negative pole of the photovoltaic module through a third resistor R23 and a fourth resistor R24. The drain of Q2 is connected to the gate of Q1 through a third resistor R23. R18 is the drive signal input resistor of the bypass module 10. R23 is the base of Q3, which receives the control signal BYPASS_CTL of the controller 30 through 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.

[0073] The driving circuit 20 takes a second voltage V2, such as 5V, from the power module to provide a turn-on voltage for Q1. The controller 30 outputs a control signal BYPASS_CTL to control Q3 to turn on or off. When BYPASS_CTL is high, Q3 is turned on, the potential between R21 and R22 is lower than 5V, Q2 is turned on, R23 and R34 generate a high potential, Q1 is turned on, and the bypass module 10 is turned on. When BYPASS_CTL is low, Q3 is turned off, the potential between R21 and R22 is equal to 5V, Q2 is turned off, R23 and R24 are low, Q1 is turned off, and the bypass module is disconnected.

[0074] refer to Figure 8 In one possible implementation, the power module 40 includes: a step-down circuit 41, which is used to convert the voltage output by at least one photovoltaic module into a second working voltage when at least one photovoltaic module is working normally. A boost circuit 42, which is used to convert the voltage between the input and output ends of at least one bypass module into a first working voltage when at least one photovoltaic module is bypassed. A switching circuit 43, which is used to compare the second working voltage with a reference voltage, and control whether the boost circuit 42 and at least one bypass module 10 are connected according to the comparison result. Optionally, the first threshold is the control voltage BYPASS_CTL output by the controller 30.

[0075] Fig. 9A possible implementation of the step-down circuit 41. It includes a first integrated chip U1, including 6 pins 411 to 416. Pin 411 is connected to the positive pole PV+ of the photovoltaic module as a voltage input terminal. 411 is connected to the negative pole PV- of the photovoltaic module through the first capacitor C1. C1 is an input voltage stabilizing capacitor, which plays a filtering and voltage stabilizing role. A seventh resistor R411 and an eighth resistor R412 are connected in series between 411 and the ground. Pin 414 is connected between R411 and R412. R411 and R412 are voltage divider resistors connected in series, which provide an enable signal for the chip 414 port to control the working state of the chip. When the enable signal is at a high potential, the chip works, and when the enable signal is at a low potential, the chip does not work. Pin 415 is connected to PV-. A second capacitor C2 is connected in series between pins 412 and 413 as a bootstrap capacitor to provide a driving voltage for the power switch tube driver in the chip. Pin 413 is the voltage output terminal of U1, and the first voltage stabilizing diode DZ1 is connected to the ground to stabilize the output port voltage. 413 is also grounded through the first inductor L1 and the third capacitor C3 connected in series. L1 and C3 form an LC filter structure to filter out high-frequency harmonics and stabilize the output DC voltage second voltage V2. The output terminal of the second voltage V2 is grounded through the ninth resistor R414 and the tenth resistor R413 connected in series. Pin 416 is connected between R414 and R413, and is used to sample the output V2 voltage to form a feedback signal to the chip U1.

[0076] In order to stabilize the voltage V2 output by the step-down circuit 41, the output end of the second voltage V2 is connected to the eighth diode D8 to form a unidirectional charging clamping voltage stabilization circuit to obtain a stable first voltage V1. V1 forms a unidirectional discharge circuit through the eleventh resistor R415 connected in series with the light-emitting diode D9 to prevent the output power supply from overvoltage. When D9 emits light, V1 has a certain amount of electrical energy. A fourth capacitor C4 is also connected between V1 and the ground for filtering and stabilizing the first voltage V1.

[0077] Fig.10A possible implementation of the boost circuit 42 is shown. It includes a second integrated chip U2, which includes 6 pins 421 to 426. 423 is the voltage input terminal of U2. 421 is connected to 423 through a second inductor. L2 is a boost inductor for storing electrical energy and raising the voltage. 423 is also grounded through a second voltage stabilizing diode DZ2 and a fifth capacitor C5 connected in parallel. C5 is a voltage stabilizing capacitor. 424 is the U2 enable terminal, and 424 is connected to the voltage input terminal 423 through a twelfth resistor R421. R421 is an enable input resistor that controls the input size of the enable signal. Pin 425 is grounded. Pin 422 is a voltage output terminal, which is grounded through a sixth capacitor C6. C6 is used to filter out interference waveforms and stabilize DC output. Pin 422 is also grounded through 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 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 .

[0078] In one possible implementation, the switching circuit 43 includes a comparator and at least one switch tube. The first signal input terminal of the comparator is used to receive the second operating voltage output by the step-down circuit, and the second signal input terminal of the comparator is used to receive a reference signal. The input terminal and output terminal of at least one switch tube are connected to the boost circuit and the bypass module. The control terminal of at least one switch tube is connected to the signal output terminal of the comparator. At least one switch tube controls the boost circuit and the bypass module to be turned on according to the output signal of the comparator. Since the bypass module is connected in parallel with the photovoltaic module, the boost circuit is turned on with the bypass module, that is, it is turned on with the photovoltaic module. Reference Figure 8 and Fig.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 working voltage V2 output by the step-down circuit U1. The second signal input terminal of U3 is used to receive a reference voltage signal. Optionally, the reference voltage signal is a control signal BYPASS_CTL output by the controller 30. The fourth transistor Q4 connects the boost circuit 42 and the bypass module 10. The signal output terminal of the comparator U3 is used to control whether Q4 is turned on or not, so as to control whether the boost circuit 42 and the bypass module 10 are turned on or not. Fig.10 The emitter of Q4 is connected to the positive electrode PV+ of the photovoltaic module, and PV+ has the same potential as the input terminal 101 of the bypass module 10 , so the emitter of Q4 is connected to the bypass module 10 at the same time.

[0079] The switching circuit 43 also includes a fifth transistor Q5. U3 uses a constant current comparator. The inverting input terminal of U3 is connected to the second voltage V2 through the fifteenth resistor R431. R431 is an input resistor that controls the reference of the input current. The output terminal of U3 is connected to the base of Q5 through the sixteenth resistor R433. The output terminal of U3 is grounded through the sixteenth resistor R433 and the seventeenth resistor R434 connected in series. R434 is a charge and discharge resistor, which is connected in series between the base and the emitter of the transistor Q5. The eighteenth resistor R432 and the nineteenth resistor R435 are connected in series between the positive pole of the photovoltaic module and the collector of Q5. R432 and R435 are voltage divider resistors. R432 is connected between the collector and the base of Q4. R435 is connected between the base of Q4 and the collector of Q5. Optionally, Q4 is a P-channel transistor and Q5 is an N-channel transistor. The collector of Q4 serves as the voltage output terminal of the switching circuit 43 and is connected to the voltage input terminal 423 of U2.

[0080] The working principle of the power module 40 is as follows: the power module is divided into two power supply states: normal operation of the photovoltaic module and bypass conduction. When the bypass module is disconnected, the photovoltaic module works normally and outputs electric energy to the outside. The output voltage is, for example, 17 to 60V. At this time, the buck circuit 41 works to reduce the voltage output by the photovoltaic module and convert it into a second voltage V2. After further internal voltage reduction, the first voltage V1 is output to stably supply power to the controller 30. When the bypass module 10 is turned on, the bypass module 10 forms a unidirectional conduction bypass through the reverse current protection unit 12, and forms a predetermined voltage drop through the voltage drop adjustment unit to ensure that the boost circuit works normally. At this time, the boost circuit 42 converts the voltage at the input and output ends of the bypass module 10 into the first voltage V1, and stably supplies power to the controller 30. In order 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, for example, when it is less than 3.3V, the boost circuit 42 is turned on with the bypass module 41. Since the bypass module 41 bypasses the photovoltaic assembly, the voltage output by the photovoltaic assembly is the voltage between the input end and the output end of the bypass module 41 , and the boost circuit 42 boosts the voltage to obtain a stable first voltage.

[0081] The power module of the present application realizes bypass low-voltage DC power supply, solves the problem of DC low-voltage power supply in bypass mode, provides a stable auxiliary power supply for the control device, ensures the stable operation of the photovoltaic array, and makes the photovoltaic system generate electricity safely and efficiently.

[0082] refer to Figure 8 and Fig.10In a possible implementation of the present application, the power module 40 also includes a voltage regulator 44. It includes a fourth chip U4, which is used to realize 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. The optional U4 is a linear voltage regulator chip. Pin 441 is a voltage input terminal, which is used to receive the first voltage V1. 441 is grounded through the seventh capacitor C7. C3 is an input filter capacitor, which is used to stabilize the input power supply. Pin 442 is an enable terminal, connected to pin 441, and is used to receive the first voltage V1. 443 is grounded. 445 is a voltage output terminal, which is grounded through the eighth capacitor C8. C8 is used to stabilize the output DC power supply.

[0083] In a possible implementation of the present application, the controller further includes: a voltage detection circuit 60 and a temperature detection circuit 70, which are used to monitor the working state of the photovoltaic module. The voltage detection circuit 60 is used to obtain the voltage output by at least one photovoltaic module; the temperature detection circuit 70 is used to obtain the temperature of at least one photovoltaic module. When the photovoltaic module generates electricity, the illumination and the temperature of the solar panel will affect the current of the solar panel. Within a certain range, the stronger the illumination, the greater the output current, and the higher the temperature, the smaller the output voltage. When the photovoltaic module fails, the photovoltaic curve voltage is very small. The voltage detection circuit 60 can be used to determine whether it has failed, and the detection signal is sent to the controller 30. If a failure occurs, the controller 30 controls the bypass module to be unidirectionally conducted, thereby protecting the photovoltaic module and stabilizing the string system. By adopting the voltage detection circuit 60 and the temperature detection circuit 70, single component status monitoring is realized, and the protection of the photovoltaic module is more accurate.

[0084] Optionally, the photovoltaic module control device also 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 encapsulated in one chip. When it is necessary to actively shut down the photovoltaic module, such as in special circumstances such as a house fire, the controller 30 receives a remote control signal through the communication module 50, controls the drive circuit 20 to turn on the bypass module 10, and realizes bypass short-circuit protection of the photovoltaic module. Optionally, the communication module 50 is a short-distance communication module or a long-distance communication module. The short-distance communication module includes a Bluetooth module, a WIFI module, a ZigBee module, an Ethernet module, a serial port module, a parallel port module, etc., and the long-distance communication module includes a GPRS module, a 2G module, a 3G module, a 4G module, a 5G module, an LTE module, etc.

[0085] Optional, such as Figure 8 As shown, the photovoltaic module control device is packaged together with the bypass diodes (D1, D2 and D3) of the solar cells of the photovoltaic module, for example, they are arranged in the same junction box.

[0086] Optionally, the power module 40 also supplies power to the communication module 50 , the voltage detection circuit 60 and the temperature detection circuit 70 .

[0087] Fig.12 The photovoltaic array adopts a single-control photovoltaic module control device. The photovoltaic array is composed of multiple photovoltaic modules connected in series and parallel. According to the arrangement of coordinates, the positions and marks of n×m modules can be obtained. Each photovoltaic module is connected to a bypass-type fast control device. When an accident occurs to a photovoltaic module, the bypass module connected in parallel with the photovoltaic module can be quickly turned on to short-circuit the module and ensure the safety of the power system. The single-control photovoltaic module control device can realize the status monitoring of a single module.

[0088] Fig.13 The photovoltaic array adopts a multi-control photovoltaic module control device. The photovoltaic array adopts a photovoltaic module bypass type fast switch multi-module implementation case to draw power from a single photovoltaic module to power the controller 30 and other modules. The controller 30 can realize the bypass protection mechanism of multiple photovoltaic modules and reduce costs.

[0089] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0090] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A photovoltaic module control device, characterized in that: include: At least one bypass module, a drive circuit, a power module and a controller; the at least one bypass module is used to be connected in parallel with at least one photovoltaic component; the power module is used to be connected with the at least one photovoltaic component and the at least one bypass module; The at least one bypass module is used to bypass the at least one photovoltaic assembly under the control of the controller; The driving circuit is used to drive the at least one bypass module to work under the control of the controller; The power module is used to obtain electric energy from the at least one photovoltaic component when the at least one photovoltaic component is operating normally and when the at least one photovoltaic component is bypassed, and output the electric 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 component is in a bypass mode.

2. The photovoltaic module control device according to claim 1, characterized in that: The at least one bypass module comprises a power switch, the input end and the output end of the power switch are respectively connected to the positive electrode and the negative electrode of the at least one photovoltaic component, and the control end of the power switch is used to receive the driving signal of the driving circuit.

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

4. The photovoltaic module control device according to claim 2, characterized in that: The at least one bypass module further includes: a voltage drop regulating unit, which is used to regulate the voltage drop between the input end and the output end of the at least one bypass module to a predetermined value when the power switch is in an operating state.

5. The photovoltaic module control device according to claim 2, characterized in that: The at least one bypass module further includes: at least one diode, wherein the at least one diode is connected in series with the power switch component.

6. The photovoltaic module control device according to any one of claims 1 to 5, characterized in that: The power module comprises: a step-down circuit, which is used for converting the voltage output by the at least one photovoltaic component into a second working voltage when the at least one photovoltaic component works normally.

7. The photovoltaic module control device according to claim 6, characterized in that: The power module comprises: a boost circuit for converting a voltage between an input terminal and an output terminal of the at least one bypass module into a first operating voltage when the at least one photovoltaic component is bypassed.

8. The photovoltaic module control device according to claim 7, characterized in that: The power supply module includes: a switching circuit, which is used to compare the second working voltage with a reference voltage, and control whether the boost circuit and the at least one bypass module are connected according to the comparison result.

9. The photovoltaic module control device according to claim 8, characterized in that: The switching circuit includes a comparator and at least one switch tube, wherein the first signal input end of the comparator is used to receive the second working voltage output by the step-down circuit, and the second signal input end of the comparator is used to receive a reference signal; the input end and the output end of the at least one switch tube are connected to the boost circuit and the bypass module; and the control end of the at least one switch tube is connected to the signal output end of the comparator.

10. The photovoltaic module control device according to claim 9, characterized in that: The at least one bypass module includes two or more bypass modules connected in series, and the two or more bypass modules connected in series are used to be connected in parallel with at least one photovoltaic component.

11. The photovoltaic module control device according to claim 1, characterized in that: The controller further comprises: 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 component; The temperature detection circuit is used to obtain the temperature of at least one photovoltaic component.

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