Boost circuit and photovoltaic module thereof

Abstract

The utility model provides a boost circuit and a photovoltaic module thereof, in the circuit, the anode of a first diode is connected with a first input end, the anode of a second diode is connected with the cathode of the first diode, and the cathode of the second diode is connected with a first output end; the first end of the first transistor is connected with the first input end, the first end of the second transistor is connected with the second end of the first transistor, and the second end of the second transistor is connected with the second input end and the second output end; the first end of the flying capacitor is connected with the cathode of the first diode, and the second end of the flying capacitor is connected with the second end of the first transistor; and the pre-charging unit is connected with the second end of the flying capacitor and is configured to connect a conductive path between the second end of the flying capacitor and the second input end before the flying capacitor is charged, so that the flying capacitor is pre-charged. According to the method, the flying capacitor is pre-charged, so that the problem that components of a circuit are damaged by impact current caused by current conduction of equipment is solved.

Description

Technical Field

[0001] The present application mainly relates to the field of electronic power technology, and in particular to a boost circuit and a photovoltaic component thereof. Background Art

[0002] With the gradual upgrading and expansion of the current industry, the requirements for energy use and environmental protection are gradually increasing. The use of solar energy as a renewable energy source can meet part of the energy demand and protect the environment. Solar energy is the cleanest, safest and most reliable energy in the future. The photovoltaic industry is becoming another explosively developing industry after the IT and microelectronics industries in the world. In my country, nearly 76% of the land area has abundant sunlight, and the light energy resources are evenly distributed. Compared with wind energy, hydropower and nuclear energy, solar energy does not have any noise and emissions, and its technology is relatively mature, safe and reliable.

[0003] In the current photovoltaic field, for photovoltaic module inputs exceeding 1000 volts, a three-level topology boost circuit is usually used. The three-level circuit used can effectively reduce the voltage stress of semiconductor devices, making it easy to select semiconductor devices with appropriate power. Utility Model Content

[0004] The main purpose of the present application is to provide a boost circuit and a photovoltaic assembly thereof to solve the problem of damage to the circuit and its components caused by the impact current generated at the moment of starting and stopping during the existing flying capacitor charging process.

[0005] To solve the above problems, the present application provides a boost circuit, which includes: a first diode and a second diode, the anode of the first diode is connected to the first input terminal, the anode of the second diode is connected to the cathode of the first diode, and the cathode of the second diode is connected to the first output terminal; a first transistor and a second transistor, the first end of the first transistor is connected to the first input terminal, the first end of the second transistor is connected to the second end of the first transistor, and the second end of the second transistor is connected to the second input terminal and the second output terminal; a flying capacitor, the first end of the flying capacitor is connected to the cathode of the first diode, and the second end of the flying capacitor is connected to the second end of the first transistor; a pre-charging unit, the pre-charging unit is connected to the second end of the flying capacitor, and the pre-charging unit is configured to connect the conductive path between the second end of the flying capacitor and the second output terminal before the flying capacitor is charged, so as to pre-charge the flying capacitor.

[0006] In one embodiment, the pre-charging unit includes: a third transistor, a first end of the third transistor is connected to the second end of the flying capacitor, and the second end of the third transistor is connected to the second input end; a current limiting module, and the current limiting module is arranged on the path formed by the third transistor; wherein the third transistor is configured to be turned on before the flying capacitor is charged, and to be turned off when the flying capacitor is charged.

[0007] In one embodiment, the current limiting module includes a first resistor, a first end of the first resistor is connected to the second end of the flying capacitor, and a second end of the first resistor is connected to the first end of the third transistor.

[0008] In one embodiment, the pre-charging unit further includes an optical coupler, a first end of a secondary side of the optical coupler is connected to a power source, and a second end of a secondary side of the optical coupler is connected to a control end of the third transistor.

[0009] In one embodiment, the boost circuit further includes a first capacitor, a first end of the first capacitor is connected to the first input end, and a second end of the first capacitor is connected to the second input end.

[0010] In one embodiment, the boost circuit further includes: a first inductor, wherein a first end of the first inductor is connected to the first input end, and a second end of the first inductor is connected to the first end of the first transistor; and a second inductor, wherein a first end of the second inductor is connected to the second input end, and a second end of the second inductor is connected to the second end of the second transistor.

[0011] In one embodiment, the boost circuit further includes: a second capacitor, a first end of the second capacitor is connected to the first output end, and a second end of the second capacitor is connected to the second output end.

[0012] In one embodiment, the boost circuit further includes: a third capacitor and a fourth capacitor, wherein the first end of the third capacitor is connected to the first output end, the first end of the fourth capacitor is connected to the second end of the third capacitor, and the second end of the fourth capacitor is connected to the second output end; a third diode and a fourth diode, wherein the anode of the third diode is connected to the second end of the third capacitor, the cathode of the third diode is connected to the first end of the flying capacitor, the anode of the fourth diode is connected to the second end of the flying capacitor, and the cathode of the fourth diode is connected to the second end of the third capacitor.

[0013] To solve the above problems, the present application also provides a photovoltaic component, wherein the photovoltaic component includes: a photovoltaic device; a boost circuit, wherein the first input end of the boost circuit is connected to the positive pole of the photovoltaic device, and the second input end of the boost circuit is connected to the negative pole of the photovoltaic device, and the boost circuit is the boost circuit described in the above embodiment.

[0014] In one embodiment, the photovoltaic component also includes a first switch and a second switch, wherein the first end of the first switch is connected to the positive pole of the photovoltaic device, the second end of the first switch is connected to the first input end, the first end of the second switch is connected to the negative pole of the photovoltaic device, and the second end of the second switch is connected to the second input end.

[0015] Through the above-mentioned boost circuit and its photovoltaic module, the problem of damage to components in the boost circuit due to the instantaneous impact current generated when the high-voltage photovoltaic module starts and stops during the pre-charging of the flying capacitor is solved, and the existing driving power supply is used to save the power demand for a separate power supply to meet the pre-charging demand of the flying capacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0017] Figure 1 is a structural schematic diagram of a first embodiment of a boost circuit provided by the present application;

[0018] Figure 2 is a structural schematic diagram of a second embodiment of a boost circuit provided by the present application;

[0019] Figure 3 is a structural schematic diagram of a third embodiment of a boost circuit provided by the present application;

[0020] Figure 4 is a structural schematic diagram of a fourth embodiment of a boost circuit provided by the present application;

[0021] Figure 5 is a structural schematic diagram of a fifth embodiment of a boost circuit provided by the present application;

[0022] Figure 6 is a structural schematic diagram of a first embodiment of a photovoltaic assembly provided by the present application;

[0023] Figure 7 It is a structural schematic diagram of the second embodiment of the photovoltaic assembly provided in this application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be appreciated that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the art without making creative work are within the scope of protection of the present application.

[0025] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0027] For the current high-voltage photovoltaic modules, in the case of photovoltaic module input environments exceeding 1000 volts, a three-level topology boost circuit is usually used for input. The use of a three-level circuit can effectively reduce the voltage stress in the power semiconductor device, so that it is easier to select a suitable power semiconductor device, which is beneficial to the selection of components in the circuit and circuit design. However, in current applications, when the circuit is turned on, a huge charging current will be generated. The impact current generated at the moment of turn-on will cause damage to the components inside the circuit, thereby causing irreversible damage to the circuit. Therefore, there is an urgent need for a flying capacitor pre-charging circuit that can pre-charge the flying capacitor and solve the impact current problem, so as to realize the pre-charging of the flying capacitor circuit for maximum power point tracking.

[0028] Among them, the three-level topology (NPC, Neutral Point Clamped) is the most widely used multi-level topology. In recent years, with the development of power electronics technology in the power industry, NPC three-level technology has begun to be applied to various fields more and more, including photovoltaic inverters, wind power converters, high-voltage inverters, UPS, APF / SVG, high-frequency power supplies, etc. There are three common three-level topologies, namely diode clamped type, flying capacitor type, and symmetrical three-level topology. Although the three-level circuit is relatively more complex in topology, compared with the traditional two-level inverter circuit that can only output high and low levels, this novel inverter circuit can output high and low levels by turning on the upper and lower tubes, and output zero level by clamping the middle diode, a total of three levels, so it is called a three-level inverter circuit.

[0029] See also Figure 1 As shown, Figure 1 1 is a schematic diagram of the structure of the first embodiment of the boost circuit provided by the present application. The boost circuit 100 includes: a first capacitor C1, a second capacitor C2, a first inductor L1, a second inductor L2, a first diode D1, a second diode D2, a first transistor Q1, a second transistor Q2, a flying capacitor C0 and a pre-charging unit 10.

[0030] The specific connection relationship is:

[0031] The first end of the first capacitor C1 is connected to the first input end, and the second end of the first capacitor C1 is connected to the second input end; the first end of the first inductor L1 is connected to the first end of the first capacitor C1; the first end of the second inductor L2 is connected to the second end of the first capacitor C1; the anode of the first diode D1 is connected to the second end of the first inductor L1, the anode of the second diode D2 is connected to the cathode of the first diode D1, and the cathode of the second diode D2 is connected to the first output end; the first end of the first transistor Q1 is connected to the second end of the first inductor L1, the first end of the second transistor Q2 is connected to the second end of the first transistor Q1, and the second end of the second transistor Q2 is connected to the second end of the second inductor L2 and the second output end; the first end of the flying capacitor C0 is connected to the cathode of the first diode D1, and the second end of the flying capacitor C0 is connected to the second end of the first transistor Q1; the pre-charging unit 10 is connected to the second end of the flying capacitor C0, and the pre-charging unit 10 is configured to connect the conductive path between the second end of the flying capacitor C0 and the second output end before the flying capacitor C0 is charged, so as to pre-charge the flying capacitor C0.

[0032] Optionally, in one embodiment, the first capacitor C1 is used as an input capacitor, the second capacitor C2 is used as an output capacitor, and the first input terminal and the second input terminal can be connected to the positive electrode and the negative electrode of the photovoltaic device respectively.

[0033] Furthermore, the boost circuit 100 also includes a controller, which is connected to the control end of the first transistor Q1 and the control end of the second transistor Q2, and is used to output a control signal to control the conduction and disconnection of the first transistor Q1 and the second transistor Q2, thereby achieving the boost output of the above-mentioned boost circuit 100.

[0034] It can be understood that, in this embodiment, the first transistor Q1 and the second transistor Q2 are illustrated by taking MOS transistors as examples, and in other embodiments, they may also be triodes or other semiconductor switch devices.

[0035] The specific working principle of the above circuit is as follows:

[0036] First mode:

[0037] The controller controls the first transistor Q1 and the second transistor Q2 to be disconnected, and the first input terminal, the first inductor L1, the first diode D1, the second diode D2, the second capacitor C2, the second inductor L2, and the second input terminal form a current loop, and work in the freewheeling mode. In the freewheeling mode, the voltage of the flying capacitor C0 remains unchanged, the current of the first inductor L1 and the second inductor L2 decreases, and the output voltage increases.

[0038] Second mode:

[0039] The controller controls the first transistor Q1 to be disconnected and the second transistor Q2 to be turned on, and the first input terminal, the first inductor L1, the first diode D1, the flying capacitor C0, the second transistor Q2, the second inductor L2, and the second input terminal form a current loop. The first input terminal, the first inductor L1, the first diode D1, the second diode D2, the second capacitor C2, the second inductor L2, and the second input terminal form a current loop, and the flying capacitor C0 is charged and its voltage increases.

[0040] Third mode:

[0041] The controller controls the first transistor Q1 to be turned on and the second transistor Q2 to be turned off, and the first input terminal, the first inductor L1, the first transistor Q1, the flying capacitor C0, the second diode D2, the second capacitor C2, the second inductor L2, and the second input terminal form a current loop, and the flying capacitor C0 discharges and its voltage decreases.

[0042] Fourth mode:

[0043] The controller controls the first transistor Q1 and the second transistor Q2 to be turned on, and the first input terminal, the first inductor L1, the first transistor Q1, the second transistor Q2, the second inductor L2, and the second input terminal form a current loop, and the voltage of the flying capacitor C0 remains unchanged.

[0044] It can be understood that in the process from the first mode to the second mode, the voltage of the flying capacitor C0 increases suddenly, and the flying capacitor C0 will generate a large impact current at the moment of being turned on, which may cause damage to the second transistor Q2.

[0045] Therefore, in this embodiment, by connecting the pre-charging unit 10 to the second end of the flying capacitor C0, the pre-charging unit 10 is configured to connect the conductive path between the second end of the flying capacitor C0 and the second output end before the flying capacitor C0 is charged, so that the flying capacitor C0 is pre-charged. For example, pre-charging is performed through the loop of the first input end, the first inductor L1, the first diode D1, the flying capacitor C0, the pre-charging unit 10, the second inductor L2, and the second input end. The above-mentioned boost circuit is used to solve the problem that on the basis of the original traditional switching power supply, there is a current overshoot in the instantaneous situation of circuit switching in the boost circuit, which causes some components in the circuit to fail or even be damaged under excessive impact.

[0046] Optionally, in one embodiment, if Figure 2 As shown, Figure 2 It is a structural schematic diagram of the second embodiment of the boost circuit provided by the present application; wherein, specifically, the pre-charging unit 10 includes: a third transistor Q3, a first end of the third transistor Q3 is connected to the second end of the flying capacitor C0, and the second end of the third transistor Q3 is connected to the second input end; a current limiting module 11, and the current limiting module 11 is arranged on the path formed by the third transistor Q3; wherein the third transistor Q3 is configured to be turned on before the flying capacitor C0 is charged, and to be turned off when the flying capacitor C0 is charged.

[0047] Optionally, in one embodiment, if Figure 3 As shown, Figure 3 It is a structural schematic diagram of the third embodiment of the boost circuit provided in the present application; wherein, the current limiting module 11 includes a first resistor R1, a first end of the first resistor R1 is connected to the second end of the flying capacitor C0, and a second end of the first resistor R1 is connected to the first end of the third transistor Q3.

[0048] Among them, the current limiting module 11 can be composed of a plurality of resistors connected in series or in parallel, or other load components as components with current limiting function, that is, it can meet the current limiting function in the circuit, and no specific limitation is made here.

[0049] Optionally, in one embodiment, if Figure 2 and Figure 3 As shown, the pre-charging unit 10 further includes an optical coupler 12 , a first end of a secondary side of the optical coupler 12 is connected to a power source, and a second end of a secondary side of the optical coupler 12 is connected to a control end of the third transistor Q3 .

[0050] Specifically, the driving optocoupler 12 of the third transistor Q3 can be powered by the driving power supply voltage of the second transistor Q2 at the same time, so as to save a separate power supply system.

[0051] Among them, the optical coupler (OC) is also called a photoelectric isolator or a photoelectric coupler, or simply an optocoupler. It is a device that uses light as a medium to transmit electrical signals. Usually, the light emitter (infrared light-emitting diode LED) and the light receiver (photosensitive semiconductor tube) are encapsulated in the same tube shell. When an electrical signal is applied to the input end, the light emitter emits light, and the light receiver generates a photocurrent after receiving the light, which flows out from the output end, thus realizing the "electric-light-electric" conversion.

[0052] Optionally, in one embodiment, if Figure 4 and Figure 5 As shown, Figure 4 is a structural schematic diagram of a fourth embodiment of a boost circuit provided by the present application; Figure 5 It is a structural schematic diagram of the fifth embodiment of the boost circuit provided in the present application; wherein, the boost circuit 100 includes: a first capacitor C1, a second capacitor C2, a first inductor L1, a second inductor L2, a first diode D1, a second diode D2, a first transistor Q1, a second transistor Q2, a flying capacitor C0, a pre-charging unit 10, a third capacitor C3, a fourth capacitor C4, a third diode D3 and a fourth diode D4.

[0053] The specific connection relationship is:

[0054] The first end of the first capacitor C1 is connected to the first input end, and the second end of the first capacitor C1 is connected to the second input end; the first end of the first inductor L1 is connected to the first end of the first capacitor C1; the first end of the second inductor L2 is connected to the second end of the first capacitor C1; the anode of the first diode D1 is connected to the second end of the first inductor L1, the anode of the second diode D2 is connected to the cathode of the first diode D1, and the cathode of the second diode D2 is connected to the first output end; the first end of the first transistor Q1 is connected to the second end of the first inductor L1, the first end of the second transistor Q2 is connected to the second end of the first transistor Q1, and the second end of the second transistor Q2 is connected to the second end of the second inductor L2 and the second output end; the first end of the flying capacitor C0 is connected to the cathode of the first diode D1, and the second end of the flying capacitor C0 is connected to the second end of the first transistor Q1; the pre-charging unit 10 is connected to the second end of the flying capacitor C0, and the pre-charging unit 10 is configured to connect the conductive path between the second end of the flying capacitor C0 and the second output end before the flying capacitor C0 is charged, so as to pre-charge the flying capacitor C0. The first end of the third capacitor C3 is connected to the first output end, the first end of the fourth capacitor C4 is connected to the second end of the third capacitor C3, and the second end of the fourth capacitor C4 is connected to the second output end; the anode of the third diode D3 is connected to the second end of the third capacitor C3, the cathode of the third diode D3 is connected to the first end of the flying capacitor C0, the anode of the fourth diode D4 is connected to the second end of the flying capacitor C0, and the cathode of the fourth diode D4 is connected to the second end of the third capacitor C3.

[0055] Optionally, in one embodiment, the first capacitor C1 is used as an input capacitor, the third capacitor C3 and the fourth capacitor C4 are used as output capacitors, and the first input terminal and the second input terminal can be connected to the positive electrode and the negative electrode of the photovoltaic device respectively.

[0056] Further, in this embodiment, the boost circuit 100 also includes a controller, which is connected to the control end of the first transistor Q1 and the control end of the second transistor Q2, and is used to output a control signal to control the conduction and disconnection of the first transistor Q1 and the second transistor Q2, thereby realizing the boost output of the above-mentioned boost circuit 100.

[0057] It can be understood that, in this embodiment, the first transistor Q1 and the second transistor Q2 are illustrated by taking MOS transistors as examples, and in other embodiments, they may also be triodes or other semiconductor switch devices.

[0058] The specific working principle of the above circuit is as follows:

[0059] First mode:

[0060] The controller controls the first transistor Q1 and the second transistor Q2 to be disconnected, and the first input terminal, the first inductor L1, the first diode D1, the second diode D2, the third capacitor C3, the fourth capacitor C4, the second inductor L2, and the second input terminal form a current loop and work in the freewheeling mode. In the freewheeling mode, the voltage of the flying capacitor C0 remains unchanged, the current of the first inductor L1 and the second inductor L2 decreases, and the output voltage increases. Among them, the third capacitor C3 and the fourth capacitor C4 are connected in series to provide a three-level output.

[0061] Second mode:

[0062] The controller controls the first transistor Q1 to be disconnected and the second transistor Q2 to be turned on, and the first input terminal, the first inductor L1, the first diode D1, the flying capacitor C0, the second transistor Q2, the second inductor L2, and the second input terminal form a current loop. The first input terminal, the first inductor L1, the first diode D1, the second diode D2, the third capacitor C3, the fourth capacitor C4, the second inductor L2, and the second input terminal form a current loop, and the flying capacitor C0 is charged, and its voltage increases.

[0063] Third mode:

[0064] The controller controls the first transistor Q1 to be turned on and the second transistor Q2 to be turned off, and the first input terminal, the first inductor L1, the first transistor Q1, the fourth capacitor C4, the second inductor L2, and the second input terminal form a current loop, and the flying capacitor C0 is discharged, and its voltage decreases.

[0065] Fourth mode:

[0066] The controller controls the first transistor Q1 and the second transistor Q2 to be turned on, and the first input terminal, the first inductor L1, the first transistor Q1, the second transistor Q2, the second inductor L2, and the second input terminal form a current loop, and the voltage of the flying capacitor C0 remains unchanged.

[0067] Among them, before the corresponding second transistor Q2 is turned on, the pre-charging unit 10 is turned on. At this time, the voltage across the fourth capacitor C4 charges the flying capacitor C0 through the pre-charging unit 10 and the third diode D3. For example, when the flying capacitor C0 is charged to be equal to the voltage of the third capacitor C3, the pre-charging unit 10 is disconnected and the second transistor Q2 is turned on. Since the voltage across the third capacitor C3 is equal to the voltage across the flying capacitor C0 at this time, the current flowing into the second transistor Q2 will not have the problem of impact current, thereby solving the problem of damage to the second transistor Q2 caused by the impact current.

[0068] It can be understood that in the above embodiment, by connecting the pre-charging unit 10 to the second end of the flying capacitor C0, the pre-charging unit 10 is configured to connect the conductive path between the second end of the flying capacitor C0 and the second output end before the flying capacitor C0 is charged, so as to pre-charge the flying capacitor C0. For example, before turning on the second transistor Q2, the pre-charging unit 10 is turned on to form a path between the fourth capacitor C4, the third diode D3, the flying capacitor C0 and the pre-charging unit, so that the fourth capacitor C4 can pre-charge the flying capacitor C0. After the flying capacitor is pre-charged to a certain extent, the second transistor Q2 is controlled to be turned on and the pre-charging unit 10 is disconnected, so that a loop is formed between the second input terminal, the second inductor L2, the second transistor Q2, the flying capacitor C0, the second diode D2 and the first output terminal, and the flying capacitor C0 is directly charged and energized; wherein, it can be set that when the flying capacitor C0 is pre-charged to the point where the voltage across the flying capacitor C0 is equal to the voltage across the third capacitor C3, the pre-charging unit 10 is controlled to be disconnected and then the second transistor Q2 is turned on. The charging time can also be used as a judgment to realize the on-off control of the pre-charging unit 10 and the second transistor after a certain period of time. It can be set according to actual needs and implementation conditions, and is not specifically limited here. Through the above-mentioned boost circuit and its photovoltaic module, the problem of damage to components in the boost circuit due to the instantaneous impact current generated when the high-voltage photovoltaic module starts and stops during the pre-charging of the flying capacitor is solved, and the existing driving power supply is used to save the power demand for a separate power supply to meet the pre-charging demand of the flying capacitor.

[0069] Optionally, in one embodiment, if Figure 5As shown, the first resistor R1 and the third transistor Q3 are added to realize pre-charging of the flying capacitor C0 voltage in the boost circuit, and the third transistor Q3 is controlled to be turned on before charging is turned on, so that the fourth capacitor C4 charges and supplies energy to the flying capacitor C0 through the third transistor Q3, the first resistor R1 and the third diode D3. When the voltage across the flying capacitor C0 is charged to be equal to the voltage across the third capacitor C3, the charging and energy supply is stopped and the third transistor Q3 is disconnected, and the second transistor Q2 is turned on to continue charging the system circuit. However, since the voltage across the flying capacitor C0 is almost equal to the voltage across the third capacitor C3 at this time, there will be no impact current in the second transistor Q2, which will cause the second transistor Q2 to be overheated and damaged due to excessive current impact, thereby solving the problem of wave damage of the second transistor Q2, and the power supply voltage driven by the second transistor Q2 can be used to power the driving optical coupler 12 of the third transistor Q3 at the same time to meet its energy supply requirements, eliminating a separate power supply system, which is conducive to cost saving.

[0070] The present application also provides a photovoltaic module, see Figure 6 As shown, Figure 6 It is a structural schematic diagram of the first embodiment of the photovoltaic component provided in the present application; wherein the photovoltaic component 300 includes: a photovoltaic device 200; a boost circuit 100, wherein the first input end of the boost circuit 100 is connected to the positive pole of the photovoltaic device 200, and the second input end of the boost circuit 100 is connected to the negative pole of the photovoltaic device 200, and the boost circuit 100 is the boost circuit 100 described in the above embodiment.

[0071] The photovoltaic module 300 is a device that connects a number of single cells in series and parallel, and then seals them into a whole, so that it can convert solar energy into electrical energy. Common photovoltaic modules are mostly flat-panel packaging structures. The top layer of the photovoltaic module is a low-iron, high-transmittance tempered glass plate, which has two functions. The first is to allow light to pass through and irradiate the battery cell, and the second is to fix and support the solar cell. The middle layer of the module is composed of polymer EVA (ethylene-vinyl acetate copolymer) and solar cells. The EVA polymer wraps the solar cell to fix and protect the solar cell. The bottom layer of the module is composed of an alloy composite film that is anti-aging, corrosion-resistant and has good electrical insulation properties. The photovoltaic equipment 200 refers to the machinery and equipment used by photovoltaic manufacturing companies to produce raw materials, battery components, parts and other products, and basically maintains the original physical form and function during repeated use.

[0072] In the above embodiment, the photovoltaic device 200 converts the received solar energy into electrical energy to supply power to the boost circuit 100, thereby completing the charging and energy supply of the flying capacitor C0 therein.

[0073] Optionally, in one embodiment, if Figure 7 As shown, Figure 7 It is a structural schematic diagram of the second embodiment of the photovoltaic component provided by the present application; wherein, specifically, the photovoltaic component 300 also includes a first switch 310 and a second switch 320, the first end of the first switch 310 is connected to the positive pole of the photovoltaic device 200, the second end of the first switch 310 is connected to the first input terminal, the first end of the second switch 320 is connected to the negative pole of the photovoltaic device 200, and the second end of the second switch 320 is connected to the second input terminal.

[0074] It can be understood that the photovoltaic device 200 and the boost circuit 100 are controlled on and off by the first switch 310 and the second switch 320, and the power supply control of the boost circuit 100 is realized, so as to facilitate the daily use of the device and the cut-off and start-stop function during the maintenance of the device. The boost circuit 100 in the present application can also be used in other multi-level circuits with flying capacitors C0.

[0075] The boost circuit 100 provided in the present application includes: a first diode D1, a second diode D2, a first transistor Q1, a second transistor Q2, a flying capacitor C0, and a pre-charging unit 10; wherein the specific connection relationship is that the anode of the first diode D1 is connected to the first input terminal, the anode of the second diode D2 is connected to the cathode of the first diode D1, and the cathode of the second diode D2 is connected to the first output terminal; the first end of the first transistor Q1 is connected to the first input terminal, the first end of the second transistor Q2 is connected to the second end of the first transistor Q1, and the second end of the second transistor Q2 is connected to the second input terminal and the second output terminal; the first end of the flying capacitor C0 is connected to the cathode of the first diode D1, and the second end of the flying capacitor C0 is connected to the second end of the first transistor Q1; the pre-charging unit 10 is connected to the second end of the flying capacitor C0, and the pre-charging unit 10 is configured to connect the conductive path between the second end of the flying capacitor C0 and the second input terminal before the flying capacitor C0 is charged, so as to pre-charge the flying capacitor C0.

[0076] Through the above-mentioned boost circuit and its photovoltaic module, the problem of damage to components in the boost circuit due to the instantaneous impact current generated when the high-voltage photovoltaic module starts and stops during the pre-charging of the flying capacitor is solved, and the existing driving power supply is used to save the power demand for a separate power supply to meet the pre-charging demand of the flying capacitor.

[0077] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A boost circuit, characterized in that: The boost circuit comprises: a first diode and a second diode, wherein an anode of the first diode is connected to the first input terminal, an anode of the second diode is connected to the cathode of the first diode, and a cathode of the second diode is connected to the first output terminal; a first transistor and a second transistor, wherein the first end of the first transistor is connected to the first input end, the first end of the second transistor is connected to the second end of the first transistor, and the second end of the second transistor is connected to the second input end and the second output end; a flying capacitor, wherein a first end of the flying capacitor is connected to the cathode of the first diode, and a second end of the flying capacitor is connected to the second end of the first transistor; A pre-charging unit, wherein the pre-charging unit is connected to the second end of the flying capacitor, and the pre-charging unit is configured to connect the conductive path between the second end of the flying capacitor and the second output end before the flying capacitor is charged, so as to pre-charge the flying capacitor.

2. The boost circuit according to claim 1, characterized in that: The pre-charging unit comprises: a third transistor, wherein a first end of the third transistor is connected to the second end of the flying capacitor, and a second end of the third transistor is connected to the second input end; A current limiting module, wherein the current limiting module is arranged on the path formed by the third transistor; The third transistor is configured to be turned on before the flying capacitor is charged, and to be turned off when the flying capacitor is charged.

3. The boost circuit according to claim 2, characterized in that: The current limiting module includes a first resistor, a first end of the first resistor is connected to the second end of the flying capacitor, and a second end of the first resistor is connected to the first end of the third transistor.

4. The boost circuit according to claim 2, characterized in that: The pre-charging unit further includes an optical coupler, a first end of a secondary side of the optical coupler is connected to a power source, and a second end of a secondary side of the optical coupler is connected to a control end of the third transistor.

5. The boost circuit according to claim 1, characterized in that: The boost circuit further includes a first capacitor, a first end of the first capacitor is connected to the first input end, and a second end of the first capacitor is connected to the second input end.

6. The boost circuit according to claim 5, characterized in that: The boost circuit further includes: a first inductor, wherein a first end of the first inductor is connected to the first input end, and a second end of the first inductor is connected to a first end of the first transistor; A second inductor, wherein a first end of the second inductor is connected to the second input end, and a second end of the second inductor is connected to the second end of the second transistor.

7. The boost circuit according to claim 1, characterized in that: The boost circuit further includes: A second capacitor, wherein a first end of the second capacitor is connected to the first output end, and a second end of the second capacitor is connected to the second output end.

8. The boost circuit according to claim 1, characterized in that: The boost circuit further includes: a third capacitor and a fourth capacitor, wherein a first end of the third capacitor is connected to the first output end, a first end of the fourth capacitor is connected to a second end of the third capacitor, and a second end of the fourth capacitor is connected to the second output end; A third diode and a fourth diode, wherein the anode of the third diode is connected to the second end of the third capacitor, the cathode of the third diode is connected to the first end of the flying capacitor, the anode of the fourth diode is connected to the second end of the flying capacitor, and the cathode of the fourth diode is connected to the second end of the third capacitor.

9. A photovoltaic module, characterized in that: The photovoltaic module comprises: Photovoltaic equipment; A boost circuit, wherein a first input terminal of the boost circuit is connected to the positive electrode of the photovoltaic device, a second input terminal of the boost circuit is connected to the negative electrode of the photovoltaic device, and the boost circuit is a boost circuit as described in any one of claims 1-8.

10. The photovoltaic module according to claim 9, characterized in that: The photovoltaic assembly also includes a first switch and a second switch, wherein the first end of the first switch is connected to the positive pole of the photovoltaic device, the second end of the first switch is connected to the first input end, the first end of the second switch is connected to the negative pole of the photovoltaic device, and the second end of the second switch is connected to the second input end.

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