CN115473321A

CN115473321A - Solar charging circuit and solar charging system

Info

Publication number: CN115473321A
Application number: CN202211034785.5A
Authority: CN
Inventors: 何志峰; 吴朋
Original assignee: Shenzhen Hello Tech Energy Co Ltd
Current assignee: Shenzhen Hello Tech Energy Co Ltd
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2022-12-13

Abstract

The invention discloses a solar charging circuit and a solar charging system. The solar charging circuit comprises a controller, a voltage reduction module, a first switch module and a bus; the input end of the first switch module is connected with the electric energy output end of the solar panel assembly, the first output end of the first switch module is connected with the storage battery, and the second output end of the first switch module is connected with the bus; the controller is used for outputting a first driving signal when the open-circuit voltage is lower than a preset voltage threshold value and outputting a second driving signal when the open-circuit voltage is not lower than the preset voltage threshold value; the first switch module is used for controlling the electric energy output end of the solar panel assembly to be connected with the storage battery to supply power to the storage battery based on the first driving signal and controlling the electric energy output end of the solar panel assembly to be connected with the bus to supply power to the bus based on the second driving signal. By adopting the scheme, the problem of limitation of the number of the solar panels in the practical application process is solved, and the system application of various different power levels is met.

Description

Solar charging circuit and solar charging system

Technical Field

The invention relates to the technical field of solar charging, in particular to a solar charging circuit and a solar charging system.

Background

Photovoltaic power generation is more and more widely applied, and energy storage, off-grid and other systems can easily meet the requirements of residents in areas without electricity, power shortage and unstable power, and the living power, the living water and the working power of schools or factories. The power generation function of the diesel generator can be partially or completely replaced by the advantages of economy, cleanness, environmental protection and no noise of photovoltaic power generation.

The existing solar charging circuit generally adopts a Buck or Boost circuit to step down or step up, and MPPT is carried out on the input voltage of a solar panel component, namely the PV input voltage, so as to obtain the maximum input power, and the output voltage of the solar charging circuit depends on the input voltage of the solar panel component. The problem of PV input voltage wide range can not be solved to present scheme, and in practical application, the voltage that various power class's system application required is different, and solar panel assembly's output voltage needs the difference promptly, because solar panel assembly is formed by a plurality of solar panel series connection, consequently, the output voltage of solar panel assembly is influenced to the series quantity. However, on site, the solar cell panel with a small number of serial connection is configured, or the solar cell panel with a large number of serial connection is configured, and the requirement of flexibly configuring the number of solar cell strings cannot be met.

Disclosure of Invention

The invention provides a solar charging circuit and a solar charging system, which are used for solving the problem of limitation of the number of solar panels in the practical application process and meeting the application requirements of systems with different power levels.

According to an aspect of the present invention, there is provided a solar charging circuit including a controller, a voltage dropping module, a first switching module, and a bus bar;

the input end of the first switch module is connected with the electric energy output end of the solar panel assembly, the first output end of the first switch module is connected with the storage battery, and the second output end of the first switch module is connected with the bus;

the input end of the voltage reduction module is electrically connected with the bus, and the output end of the voltage reduction module is electrically connected with the storage battery;

the detection end of the controller is electrically connected with the open-circuit voltage output end of the solar panel assembly to obtain open-circuit voltage;

a first output end of the controller is electrically connected with the first switch module, and the controller is used for outputting a first driving signal when the open-circuit voltage is lower than a preset voltage threshold value and outputting a second driving signal when the open-circuit voltage is not lower than the preset voltage threshold value;

the first switch module is used for controlling the electric energy output end of the solar panel component to be connected with the storage battery to supply power to the storage battery based on the first driving signal, and controlling the electric energy output end of the solar panel component to be connected with the bus to supply power to the bus based on the second driving signal.

In an optional embodiment of the invention, the solar charging circuit further comprises a buck-boost module,

the buck-boost module is connected between the electric energy output end of the solar panel assembly and the first switch module;

a second output end of the controller is electrically connected with a first control end of the voltage boosting and reducing module, and a third output end of the controller is electrically connected with a second control end of the voltage boosting and reducing module; the controller is used for outputting a first control signal when the open-circuit voltage is lower than a preset voltage threshold value and outputting a second control signal when the open-circuit voltage is not lower than the preset voltage threshold value;

the voltage boosting and reducing module is used for reducing the voltage input by the electric energy output end of the solar panel assembly based on the first control signal and boosting the voltage input by the electric energy output end of the solar panel assembly based on the second control signal.

In an alternative embodiment of the present invention, the power output terminal of the solar panel assembly includes a positive output terminal and a negative output terminal;

the buck-boost module comprises a first MOS tube, a second MOS tube, a first diode, a second diode, an inductor, a first common point, a second common point, a third common point and a polarity capacitor;

the grid electrode of the first MOS tube is electrically connected with the second output end of the controller, the drain electrode of the first MOS tube is electrically connected with the positive output end, the source electrode of the first MOS tube is connected with the first common point, and the first MOS tube is used for being switched on and switched off based on the first control signal and the second control signal;

the cathode of the first diode is electrically connected to the first common point, and the anode of the first diode is electrically connected with the negative output end;

one end of the inductor is connected to the first common point, and the other end of the inductor is connected to the second common point;

the grid electrode of the second MOS tube is electrically connected with the third output end of the controller, the drain electrode of the second MOS tube is electrically connected with the second common point, the source electrode of the second MOS tube is connected with the ground, and the second MOS tube is used for being turned off based on the first control signal and being turned on and turned off based on the second control signal;

the anode of the second diode is connected to the second common point, and the cathode of the second diode is connected to the third common point;

the positive electrode of the polar capacitor is electrically connected with the third common point, and the negative electrode of the polar capacitor is connected with the ground;

the third common point is electrically connected with the input end of the first switch module.

In an optional embodiment of the present invention, the first switch module comprises a first switch and a second switch, the first switch is connected between the power output end of the solar panel assembly and the bus bar;

the second switch is connected between the electric energy output end of the solar panel component and the storage battery;

the first switch is configured to open based on the first drive signal and close based on the second drive signal;

the second switch is configured to close based on the first drive signal and open based on the second drive signal.

In an optional embodiment of the present invention, the solar charging circuit further comprises a DC/AC inverter and a load, wherein the DC/AC inverter is connected between the bus and the load, and is configured to convert the DC power input by the bus into AC power to supply to the load.

In an alternative embodiment of the invention, the solar charging circuit further comprises a second switching module connected between the DC/AC inverter and the load.

In an alternative embodiment of the invention, the second switching module comprises a plurality of third switches connected between the DC/AC inverter and the load;

the number of the loads is multiple and is connected with the third switches in a one-to-one correspondence mode.

In an alternative embodiment of the present invention, the voltage reduction module is a DC/DC voltage reduction module.

According to another aspect of the present invention, there is provided a solar charging system comprising a solar panel assembly, a storage battery, and a solar charging circuit according to any of the embodiments of the present invention.

According to the technical scheme, the detection end of the controller is electrically connected with the open-circuit voltage output end of the solar panel assembly to obtain the open-circuit voltage, the controller outputs a first driving signal when the open-circuit voltage is lower than a preset voltage threshold value and outputs a second driving signal when the open-circuit voltage is not lower than the preset voltage threshold value, and the first switch module is used for controlling the electric energy output end of the solar panel assembly to be connected with the storage battery to supply power to the storage battery based on the first driving signal and controlling the electric energy output end of the solar panel assembly to be connected with the bus to supply power to the bus based on the second driving signal. Meanwhile, a voltage reduction module is connected between the bus and the storage battery. Therefore, when the serial number of the solar panels is less, the open-circuit voltage is lower than the preset voltage threshold, the controller outputs a first driving signal, at the moment, the first switch module enables the solar panel assembly to directly supply power for the storage battery, when the serial number of the solar panels is more, the open-circuit voltage is not lower than the preset voltage threshold, the controller outputs a second driving signal, at the moment, the first switch module enables the solar panel assembly to supply power for the bus, all the loads usually exist in an actual system, all the loads can be directly charged through the bus, the load power requirement is optimally met, the redundant electric energy is charged for the storage battery through the voltage reduction module, therefore, no matter the serial number of the solar panels is more or less, the controller can control the first switch module according to the actual situation, the charging for the storage battery is realized, the problem of limiting the number of the solar panels in the actual application process is solved, and the system application of various different power grades is met.

It should be understood that the statements in this section do not necessarily identify key or critical features of the embodiments of the present invention, nor do they necessarily limit the scope of the invention. Other features of the present invention will become apparent from the following description.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a circuit block diagram of a solar charging circuit and a solar panel assembly connected to a storage battery according to an embodiment of the present invention;

fig. 2 is a schematic circuit diagram of a solar charging circuit and a battery according to an embodiment of the present invention.

Wherein: 1. a controller; 2. a voltage reduction module; 3. a first switch module; 31. a first switch; 32. a second switch; 4. a bus bar; 5. a solar panel assembly; 51. an electrical energy output end; 52. an open circuit voltage output terminal; 6. a storage battery; 7. a buck-boost module; 71. a first MOS transistor; 72. a second MOS transistor; 73. a first diode; 74. a second diode; 75. a first common point; 76. a second common point; 77. a third common point; 78. a polar capacitance; 79. an inductance; 8. a DC/AC inverter; 9. a second switch module; 91. a third switch; 10. and (4) loading.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Example one

Fig. 1 is a circuit block diagram of a solar charging circuit and a solar panel assembly 5 connected to a battery according to an embodiment of the present invention. As shown in fig. 1, the solar charging circuit includes a controller 1, a voltage step-down module 2, a first switching module 3, and a bus bar 4.

The input end of the first switch module 3 is connected with the electric energy output end 51 of the solar panel component 5, the first output end of the first switch module 3 is connected with the storage battery 6, and the second output end of the first switch module 3 is connected with the bus 4. The first switch module 3 is a module capable of controlling the connection or disconnection of the lines at the two ends, so that the first switch module 3 can control the connection and disconnection of the electric energy output end 51 of the solar panel assembly 5 and the bus bar 4, and also can control the connection and disconnection of the electric energy output end 51 of the solar panel assembly 5 and the storage battery 6, when the electric energy output end 51 of the solar panel assembly 5 is connected with the bus bar 4, the electric energy output by the solar panel assembly 5 can supply power to the bus bar 4, and when the electric energy output end 51 of the solar panel assembly 5 is connected with the storage battery 6, the electric energy output by the solar panel assembly 5 can supply power to the storage battery 6.

The input end of the voltage reduction module 2 is electrically connected with the bus 4, and the output end of the voltage reduction module 2 is electrically connected with the storage battery 6. The voltage reduction module 2 is a module capable of performing voltage reduction output on an input voltage.

The detection terminal of the controller 1 is electrically connected to the open circuit voltage output terminal 52 of the solar cell panel assembly 5 to obtain the open circuit voltage. The controller 1 refers to a device for performing logic control on the rest of the circuit modules, and in a specific embodiment, the controller 1 is a microprocessor. The open circuit voltage of the solar panel assembly 5 means that when the solar panel assembly 5 is placed under the irradiation of a standard light source and both ends are open, the output voltage value of the solar panel assembly 5 is formed by connecting a plurality of solar panels in series, and therefore, the number of the solar panels in series can be reflected by the open circuit voltage.

The first output end of the controller 1 is electrically connected with the first switch module 3, and the controller 1 is configured to output a first driving signal when the open-circuit voltage is lower than a preset voltage threshold, and output a second driving signal when the open-circuit voltage is not lower than the preset voltage threshold. The preset voltage threshold refers to a preset value for distinguishing the number of the solar panels connected in series, and when the open-circuit voltage is lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series is small, and when the open-circuit voltage is not lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series is large.

The first switch module 3 is used for controlling the electric energy output end 51 of the solar panel assembly 5 to be connected with the storage battery 6 to supply power to the storage battery 6 based on the first driving signal, and controlling the electric energy output end 51 of the solar panel assembly 5 to be connected with the bus bar 4 to supply power to the bus bar 4 based on the second driving signal.

The first driving signal is output when the open-circuit voltage is lower than the preset voltage threshold, at this time, the number of the series connection of the solar panels is small, and the first switch module 3 controls the electric energy output end 51 of the solar panel assembly 5 to be directly connected with the storage battery 6 so as to supply power to the storage battery 6. The second drive signal is that open circuit voltage is not less than and outputs when presetting the voltage threshold, and solar cell panel's series connection quantity is more this moment, and bus 4 is connected in order to supply power for bus 4 to the electric energy output 51 of first switch module 3 control solar cell panel subassembly 5, and is connected with step-down module 2 between bus 4 and the battery 6 to step-down module 2 can charge battery 6 after stepping down the voltage of bus 4. Therefore, no matter the number of the solar panels connected in series is large or small, the controller 1 can control the first switch module 3 according to actual conditions, and the storage battery 6 is charged. Meanwhile, when the number of the solar panels connected in series is large, energy is provided for the bus 4, the rest of the loads 10 (not shown in fig. 1) usually exist in an actual system, and the rest of the loads 10 can be directly charged through the bus 4, so that the power requirement of the loads 10 is optimally met.

Above-mentioned scheme, through setting up controller 1, step-down module 2, first switch module 3 and bus 4, the sense terminal of controller 1 is connected with the open circuit voltage output 52 electricity of solar panel assembly 5, in order to obtain open circuit voltage, controller 1 exports first drive signal when open circuit voltage is less than the preset voltage threshold, and be not less than the second drive signal of exporting when presetting the voltage threshold, first switch module 3 is used for connecting battery 6 in order to supply power for battery 6 based on first drive signal control solar panel assembly 5's electric energy output 51, and connect bus 4 in order to supply power for bus 4 based on second drive signal control solar panel assembly 5's electric energy output 51. Meanwhile, a voltage reduction module 2 is connected between the bus 4 and the storage battery 6. Therefore, when the serial number of the solar panels is small, the open-circuit voltage is lower than the preset voltage threshold, the controller 1 outputs a first driving signal, at the moment, the first switch module 3 can enable the solar panel assembly 5 to directly supply power for the storage battery 6, when the serial number of the solar panels is large, the open-circuit voltage is not lower than the preset voltage threshold, the controller 1 outputs a second driving signal, at the moment, the first switch module 3 can enable the solar panel to supply power for the bus 4, usually, other loads 10 can exist in an actual system, other loads 10 can be directly charged through the bus 4, the power requirement of the loads 10 is optimally met, the redundant electric energy is charged for the storage battery 6 through the voltage reduction module 2, therefore, no matter whether the serial number of the solar panels is large or small, the controller 1 can control the first switch module 3 according to the actual situation, the charging for the storage battery 6 is achieved, the problem of limitation of the number of the solar panels in the actual application process is solved, and the system application of various different power levels is met.

In an alternative embodiment of the present invention, as shown in fig. 2, the solar charging circuit further includes a voltage step-up/step-down module 7, and the voltage step-up/step-down module 7 is connected between the power output end 51 of the solar panel assembly 5 and the first switch module 3.

A second output end of the controller 1 is electrically connected with a first control end of the voltage boosting and reducing module 7, and a third output end of the controller 1 is electrically connected with a second control end of the voltage boosting and reducing module 7; the controller 1 is configured to output a first control signal when the open-circuit voltage is lower than a preset voltage threshold, and output a second control signal when the open-circuit voltage is not lower than the preset voltage threshold.

The voltage boosting and reducing module 7 is configured to perform voltage reduction on the voltage input by the power output end 51 of the solar panel assembly 5 based on the first control signal, and perform voltage boosting on the voltage input by the power output end 51 of the solar panel assembly 5 based on the second control signal.

The voltage boosting and reducing module 7 is a module capable of performing two functions of voltage boosting and voltage reducing, and the voltage input by the electric energy output end 51 of the solar panel assembly 5 is the PV input voltage. When the open-circuit voltage is lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series with the solar panel assembly 5 is small, at this time, the controller 1 outputs a first control signal, the voltage input by the electric energy output end 51 of the solar panel assembly 5 is reduced by the voltage increasing and reducing module 7, and then the voltage is transmitted to the storage battery 6, so that the power requirement of the load 10 is optimally met. When the open-circuit voltage is not lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series with the solar panel assemblies 5 is large, the controller 1 outputs a second control signal, the electric energy input by the electric energy output end 51 of the solar panel assembly 5 of the buck-boost module 7 is boosted, and then the boosted electric energy is output to the bus 4, so that the power requirement of the load 10 is optimally met.

On the basis of the above embodiment, the power output terminal 51 of the solar panel assembly 5 includes a positive output terminal and a negative output terminal, i.e. PV + and PV-in fig. 2.

The buck-boost module 7 includes a first MOS transistor 71, a second MOS transistor 72, a first diode 73, a second diode 74, an inductor 79, a first common point 75, a second common point 76, a third common point 77, and a polarity capacitor 78.

The gate of the first MOS transistor 71 is electrically connected to the second output terminal of the controller 1, the drain of the first MOS transistor 71 is electrically connected to the positive output terminal, the source of the first MOS transistor 71 is connected to the first common point 75, and the first MOS transistor 71 is configured to be turned on and off based on the first control signal and the second control signal.

The cathode of the first diode 73 is electrically connected to the first common point 75 and the anode of the first diode 73 is electrically connected to the negative output terminal.

One end of the inductor 79 is connected to the first common point 75 and the other end of the inductor 79 is connected to the second common point 76.

The gate of the second MOS transistor 72 is electrically connected to the third output terminal of the controller 1, the drain of the second MOS transistor 72 is electrically connected to the second common point 76, the source of the second MOS transistor 72 is connected to the ground, and the second MOS transistor 72 is configured to turn off based on the first control signal and turn on and off based on the second control signal.

The anodes of the second diodes 74 are connected to a second common point 76 and the cathodes of the second diodes 74 are connected to a third common point 77.

The positive electrode of the polar capacitor 78 is electrically connected to the third common point 77, and the negative electrode of the polar capacitor 78 is connected to ground.

The third common point 77 is electrically connected to the input of the first switch module 3.

The open-circuit voltage output by the open-circuit voltage output terminal 52 is the Upv in fig. 2, and the first control signal and the second control signal output by the controller 1 may both be PWM. The on-time is Ton and the off-time is Toff. In this embodiment, the first MOS transistor 71 is Q1, the second MOS transistor 72 is Q2, the first diode 73 is D1, the second diode 74 is D2, the inductor 79 is L, and the polarity capacitor 78 is C.

When the open-circuit voltage is lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series to the solar panel assembly 5 is small, and at this time, the first switch module 3 reduces the voltage input by the power output end 51 of the solar panel assembly 5 by increasing or decreasing the voltage, and then transmits the reduced voltage to the storage battery 6. The controller 1 sends out a first control signal to turn on and off the first MOS transistor 71, and at the same time turn off, i.e. not turn on, the second MOS transistor 72. At this time, the buck-boost module 7 forms a buck circuit, and the voltage input by the power output end 51 of the solar panel assembly 5 charges the battery 6 through the first MOS transistor 71, the inductor 79, the first diode 73, the second diode 74 and the polar capacitor 78. During Ton, current passes through the first MOS transistor 71, the inductor 79, the second diode 74 and the polarity capacitor 78 to charge the battery 6; during Toff, the first MOS transistor 71 is not conductive, and the current in the inductor 79 flows through the second diode 74, the polar capacitor 78, the battery 6 and the first diode 73, so that the freewheeling is completed and the volt-second balance is realized.

When the open-circuit voltage is not lower than the preset voltage threshold, it indicates that the number of the solar panels connected in series with the solar panel assembly 5 is large, and at this time, the first switch module 3 boosts the voltage input by the electric energy output end 51 of the solar panel assembly 5 by boosting and reducing the voltage and then transmits the voltage to the bus 4. The controller 1 sends out a second control signal to turn on and off the first MOS transistor 71 and the second MOS transistor 72. At this time, the boost-buck module 7 forms a boost circuit, and the voltage input by the power output end 51 of the solar panel assembly 5 provides energy to the bus 4 through the first MOS transistor 71, the inductor 79, the second diode 74, the second MOS transistor 72 and the polarity capacitor 78. During Ton, current flows through the first MOS transistor 71, the inductor 79 and the second MOS transistor 72, energy is stored in the inductor 79, and the polar capacitor 78 discharges the bus bar 4. During Toff, the first MOS transistor 71 and the second MOS transistor 72 are not conductive, and a current flows through the first MOS transistor 71, the inductor 79, the second diode 74, the polarity capacitor 78, and the first diode 73 to charge the bus bar 4.

In an alternative embodiment of the present invention, the first switch module 3 includes a first switch 31 and a second switch 32, and the first switch 31 is connected between the power output terminal 51 of the solar panel assembly 5 and the bus bar 4.

The second switch 32 is connected between the power output terminal 51 of the solar panel assembly 5 and the storage battery 6.

The first switch 31 is adapted to open based on the first drive signal and close based on the second drive signal.

The second switch 32 is configured to close based on the first drive signal and open based on the second drive signal.

Wherein, first switch 31 disconnection, when second switch 32 closed, solar panel assembly 5's electric energy output 51 can be connected to battery 6, thereby can supply power for battery 6, closed as first switch 31, when second switch 32 disconnection, solar panel assembly 5's electric energy output 51 can be connected to bus 4, provide energy for bus 4, this moment according to load 10 power condition, the optimization satisfies load 10 power demand, unnecessary electric energy steps down through voltage reduction module 2, charge battery 6.

In addition, when the solar charging circuit includes the step-up and step-down module 7, the step-up and step-down module 7 is connected between the electric energy output end 51 of the solar panel assembly 5 and the first switch 31 and the second switch 32, that is, the input end of the step-up and step-down module 7 is electrically connected with the electric energy output end 51 of the solar panel assembly 5, the output end of the step-up and step-down module 7 is connected with one ends of the first switch 31 and the second switch 32, the other end of the first switch 31 is connected with the bus 4, and the other end of the second switch 32 is connected with the storage battery 6. Therefore, by controlling the first switch 31 and the second switch 32, the voltage output by the power output end 51 of the solar panel assembly 5 is converted by the buck-boost module 7 and then transmitted to the bus bar 4 or the storage battery 6 under different conditions.

In an alternative embodiment of the present invention, the solar charging circuit further comprises a DC/AC inverter 8 and a load 10, wherein the DC/AC inverter 8 is connected between the bus 4 and the load 10 for converting the direct current input from the bus 4 into an alternating current to supply to the load 10. The DC/AC inverter 8 can convert the direct current into the alternating current and output the alternating current, and the load 10 generally uses the alternating current, so that the energy of the bus 4 can be conveniently supplied to the load 10 by the DC/AC inverter 8.

On the basis of the above embodiment, the solar charging circuit further includes a second switching module 9, and the second switching module 9 is connected between the DC/AC inverter 8 and the load 10. Wherein, by controlling the second switch module 9, the bus 4 can be controlled to supply power to the load 10 or the bus 4 stops supplying power to the load 10.

Illustratively, the second switching module 9 includes a plurality of third switches 91, the third switches 91 being connected between the DC/AC inverter 8 and the load 10; the number of the loads 10 is plural and is connected to the third switches 91 in one-to-one correspondence.

Among them, when the third switch 91 is closed, the DC/AC inverter 8 can be connected to the load 10, when the third switch 91 is open, the DC/AC inverter 8 can be disconnected from the load 10, and by providing a plurality of third switches 91, the power supply conditions of different loads 10 can be controlled individually, which is convenient to use.

In an alternative embodiment of the invention, the buck module 2 is a DC/DC buck module 2. The DC/DC voltage reduction module 2 is a module for reducing the voltage of the direct current and outputting the direct current, and the storage battery 6 is usually used as the direct current, so that the electric energy of the bus 4 can be conveniently converted and reduced through the DC/DC voltage reduction module 2 by arranging the DC/DC voltage reduction module 2, and the storage battery 6 is supplied with power.

Example two

The second embodiment of the present invention provides a solar charging system, which includes a solar panel assembly 5, a storage battery 6 and a solar charging circuit according to any embodiment of the present invention.

Above-mentioned scheme, when solar cell panel's that solar cell panel subassembly 5 includes series connection quantity is less, open circuit voltage is less than and predetermines the voltage threshold, controller 1 outputs first drive signal, first switch module 3 can make solar cell panel subassembly 5 directly give battery 6 power supply this moment, when solar cell panel's series connection quantity is more, open circuit voltage is not less than with predetermineeing the voltage threshold, controller 1 outputs the second drive signal, first switch module 3 can make solar cell panel give bus 4 power supply this moment, can have all the other loads 10 in the actual system usually, all the other loads 10 can directly charge through bus 4, optimize and satisfy load 10 power demand, unnecessary electric energy charges through voltage reduction module 2 to battery 6, therefore, no matter solar cell panel's series connection quantity is more or less, controller 1 can both control first switch module 3 according to actual conditions, realize charging to battery 6, the restriction problem of solar cell panel quantity in the actual application process has been solved, satisfy the system application of various different power grades.

It should be understood that various forms of the flows shown above may be used, with steps reordered, added, or deleted. For example, the steps described in the present invention may be executed in parallel, sequentially, or in different orders, and are not limited herein as long as the desired results of the technical solution of the present invention can be achieved.

The above-described embodiments should not be construed as limiting the scope of the invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made, depending on design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A solar charging circuit is characterized by comprising a controller (1), a voltage reduction module (2), a first switch module (3) and a bus (4);

the input end of the first switch module (3) is connected with the electric energy output end (51) of the solar panel assembly (5), the first output end of the first switch module (3) is connected with the storage battery (6), and the second output end of the first switch module (3) is connected with the bus (4);

the input end of the voltage reduction module (2) is electrically connected with the bus (4), and the output end of the voltage reduction module (2) is electrically connected with the storage battery (6);

the detection end of the controller (1) is electrically connected with the open-circuit voltage output end (52) of the solar panel assembly (5) to obtain open-circuit voltage;

a first output end of the controller (1) is electrically connected with the first switch module (3), and the controller (1) is used for outputting a first driving signal when the open-circuit voltage is lower than a preset voltage threshold value and outputting a second driving signal when the open-circuit voltage is not lower than the preset voltage threshold value;

the first switch module (3) is used for controlling the electric energy output end (51) of the solar panel assembly (5) to be connected with the storage battery (6) to supply power to the storage battery (6) based on the first driving signal, and controlling the electric energy output end (51) of the solar panel assembly (5) to be connected with the bus (4) to supply power to the bus (4) based on the second driving signal.

2. Solar charging circuit according to claim 1, characterized in that it further comprises a buck-boost module (7),

the buck-boost module (7) is connected between the electric energy output end (51) of the solar panel assembly (5) and the first switch module (3);

a second output end of the controller (1) is electrically connected with a first control end of the voltage boosting and reducing module (7), and a third output end of the controller (1) is electrically connected with a second control end of the voltage boosting and reducing module (7); the controller (1) is used for outputting a first control signal when the open-circuit voltage is lower than a preset voltage threshold value and outputting a second control signal when the open-circuit voltage is not lower than the preset voltage threshold value;

the voltage boosting and reducing module (7) is used for reducing the voltage input by the electric energy output end (51) of the solar panel assembly (5) based on the first control signal and boosting the voltage input by the electric energy output end (51) of the solar panel assembly (5) based on the second control signal.

3. Solar charging circuit according to claim 2, characterized in that the electrical energy output (51) of the solar panel assembly (5) comprises a positive output and a negative output;

the buck-boost module (7) comprises a first MOS (metal oxide semiconductor) tube (71), a second MOS tube (72), a first diode (73), a second diode (74), an inductor (79), a first common point (75), a second common point (76), a third common point (77) and a polarity capacitor (78);

the grid electrode of the first MOS tube (71) is electrically connected with the second output end of the controller (1), the drain electrode of the first MOS tube (71) is electrically connected with the positive output end, the source electrode of the first MOS tube (71) is connected with the first common point (75), and the first MOS tube (71) is used for being switched on and off based on the first control signal and the second control signal;

the cathode of the first diode (73) is electrically connected to the first common point (75), and the anode of the first diode (73) is electrically connected to the negative output terminal;

one end of the inductor (79) is connected to the first common point (75), and the other end of the inductor (79) is connected to the second common point (76);

the grid electrode of the second MOS tube (72) is electrically connected with the third output end of the controller (1), the drain electrode of the second MOS tube (72) is electrically connected with the second common point (76), the source electrode of the second MOS tube (72) is connected with the ground, and the second MOS tube (72) is used for being turned off based on the first control signal and being turned on and off based on the second control signal;

the anode of the second diode (74) is connected to the second common point (76) and the cathode of the second diode (74) is connected to the third common point (77);

the positive pole of the polar capacitor (78) is electrically connected with the third common point (77), and the negative pole of the polar capacitor (78) is connected with the ground;

the third common point (77) is electrically connected to the input of the first switching module (3).

4. Solar charging circuit according to any of claims 1 to 3, characterized in that the first switch module (3) comprises a first switch (31) and a second switch (32), the first switch (31) being connected between the power output (51) of the solar panel assembly (5) and the bus bar (4);

the second switch (32) is connected between the electric energy output end (51) of the solar panel component (5) and the storage battery (6);

the first switch (31) is configured to open based on the first drive signal and close based on the second drive signal;

the second switch (32) is configured to close based on the first drive signal and open based on the second drive signal.

5. A solar charging circuit according to any one of claims 1-3, characterized in that the solar charging circuit further comprises a DC/AC inverter (8) and a load (10), the DC/AC inverter (8) being connected between the bus (4) and the load (10) for converting the direct current input from the bus (4) into an alternating current to supply to the load (10).

6. Solar charging circuit according to claim 5, characterized in that it further comprises a second switching module (9), said second switching module (9) being connected between the DC/AC inverter (8) and the load (10).

7. Solar charging circuit according to claim 6, characterized in that the second switching module (9) comprises a plurality of third switches (91), the third switches (91) being connected between the DC/AC inverter (8) and the load (10);

the number of the loads (10) is multiple and is connected with the third switches (91) in a one-to-one correspondence mode.

8. Solar charging circuit according to any of claims 1 to 3, characterized in that the voltage-reducing module (2) is a DC/DC voltage-reducing module (2).

9. A solar charging system, characterized by: comprising a solar panel assembly (5), a battery (6) and a solar charging circuit according to any of claims 1-8.