CN117220399B

CN117220399B - Lithium battery, solar power supply conversion circuit and conversion control method

Info

Publication number: CN117220399B
Application number: CN202311181341.9A
Authority: CN
Inventors: 安秋瑾; 龚永新
Original assignee: Beijing Kunlun Coast Technology Co ltd
Current assignee: Beijing Kunlun Coast Technology Co ltd
Priority date: 2023-09-13
Filing date: 2023-09-13
Publication date: 2024-03-12
Anticipated expiration: 2043-09-13
Also published as: CN117220399A

Abstract

The invention relates to the technical field of charging circuits, in particular to a lithium battery, a solar power supply conversion circuit and a conversion control method. The circuit comprises: the solar energy charging system comprises a lithium battery module, a solar energy charging control module, a voltage reducing module and a voltage comparing module; the lithium battery module is electrically connected to the first end of the voltage comparison module; one end of the solar charging control module is electrically connected with one end of the voltage reduction module, and the other end of the solar charging control module is grounded; the other end of the voltage reduction module is electrically connected with the second end of the voltage comparison module; the third end of the voltage comparison module is electrically connected to the load device. The method and the device can reasonably select and switch the power supply modes when the solar battery is used for supplying power to the load equipment or the lithium battery is used for supplying power to the load equipment.

Description

Lithium battery, solar power supply conversion circuit and conversion control method

Technical Field

The application relates to the technical field of charging circuits, in particular to a lithium battery, a solar power supply conversion circuit and a conversion control method.

Background

Solar energy is a clean energy source, and thus solar cells are now widely used. Particularly, in the use of load devices such as wireless sensors, solar cells are often used to supply power. However, the use time of many load devices is often limited by the application scenario, resulting in supporting the load devices to operate when the solar cell power is insufficient for a long time. Thus, prior art approaches have been to introduce lithium batteries to power load devices.

However, when a solar battery is used to supply power to a load device or a lithium battery is used to supply power to a load device, the current solar power supply circuit cannot reasonably select and switch between the two power supply modes, so that the switching is too frequent, and the service life of the lithium battery is shortened. Therefore, how to reasonably select and switch power supply modes when power is supplied to load equipment by using a solar battery or power is supplied to load equipment by using a lithium battery becomes a problem to be solved.

Accordingly, the inventors have recognized that there is a need for a lithium battery and solar power conversion circuit and conversion control method that solve the problems of the prior art.

Disclosure of Invention

The application provides a lithium battery and solar power supply conversion circuit, which can reasonably select and switch power supply modes when power is supplied to load equipment by using a solar battery or power is supplied to the load equipment by using the lithium battery.

The application provides a lithium battery and solar power conversion circuit, the circuit includes: the solar energy charging system comprises a lithium battery module, a solar energy charging control module, a voltage reducing module and a voltage comparing module; the lithium battery module is electrically connected to the first end of the voltage comparison module; one end of the solar charging control module is electrically connected with one end of the voltage reduction module, and the other end of the solar charging control module is grounded; the other end of the voltage reduction module is electrically connected with the second end of the voltage comparison module; the third end of the voltage comparison module is electrically connected to the load device.

By adopting the technical scheme, the solar charging control module is used for converting solar energy into a power supply voltage, so that the solar charging control module is used as a main power supply end for supplying power to load equipment; the solar charging control module is electrically connected with the voltage reducing module, so that the voltage provided by the solar panel is reduced to a voltage level suitable for load equipment through the voltage reducing module and then transmitted to the voltage comparing module; and the voltage comparison module is used for reasonably determining a module for supplying power to the load equipment according to the input lithium battery voltage level and the voltage level of the solar battery after the voltage reduction.

Optionally, the solar charging control module comprises a solar charging input unit, an overcharge and overdischarge judging unit and a first relay contact J2-1; one end of the solar charging input unit is electrically connected with one end of the overcharge and overdischarge judging unit; the other end of the overcharge and overdischarge judging unit is electrically connected to one end of the first relay contact J2-1; the other end of the first relay contact J2-1 is electrically connected to the step-down module.

Optionally, the solar charging input unit includes a solar panel T1, a first diode D1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a fuse FU, a first capacitor C1, a second capacitor C2, a stop-charging indicator light, a storage battery T2, a second relay contact J1-1, and a switch K; the first end of the solar panel T1 is electrically connected to the anode of the first diode D1; the cathode of the first diode D1 is electrically connected to the first end of the second relay contact J1-1; one end of the first resistor R1 is electrically connected to the second end of the second relay contact J1-1, and the other end of the first resistor R1 is electrically connected to the positive electrode of the stop-charging indicator lamp; one end of the fuse FU is electrically connected to the third end of the second relay contact J1-1, and the other end of the fuse FU is electrically connected to the positive electrode of the storage battery T2; one end of the switch K is electrically connected to the third end of the second relay contact J1-1, and the other end of the switch K is electrically connected to one end of the second resistor R2 and one end of the third resistor R3; the third resistor R3 is connected in parallel with the first capacitor C1, and one end of the third resistor R3 and one end of the first capacitor C1 are both electrically connected to the other end of the second resistor R2; the fifth resistor R5 is connected in parallel with the second capacitor C2, and one end of the fifth resistor R5 and one end of the second capacitor C2 are both electrically connected to the other end of the fourth resistor R4; the second end of the solar panel T1, the negative electrode of the stop-charge indicator lamp, the negative electrode of the storage battery T2, the other end of the third resistor, the other end of the first capacitor C1, the other end of the fifth resistor R5, and the other end of the second capacitor C2 are all grounded.

By adopting the circuit connection mode, the solar charging input unit can effectively manage solar charging and ensure safe charging of the battery.

Optionally, the overcharge and overdischarge judging unit includes an input control subunit, an overcharge judging subunit and an overdischarge judging subunit; the first end of the input control subunit is electrically connected with the first end of the solar charging input unit; one end of the overcharge judging subunit and one end of the overdischarge judging subunit are electrically connected to the second end of the input control subunit.

By adopting the circuit connection mode, the input control subunit can control and regulate the current and the voltage input into the overcharge judging subunit and the overdischarge judging subunit. The overcharge and overdischarge determination unit may monitor charge and discharge states of the battery and ensure that the battery is not overcharged or overdischarged, thereby extending the life of the battery and improving the safety of the system.

Optionally, the input control subunit includes a three-terminal adjustable voltage regulator U1, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a third capacitor C3; the input end of the three-terminal adjustable voltage stabilizer U1 is electrically connected with one end of the solar charging input unit; the control end of the three-terminal adjustable voltage stabilizer U1 is electrically connected with one end of the sixth resistor R6 and one end of the seventh resistor R7; the other end of the sixth resistor R6 and one end of the eighth resistor R8 are electrically connected to the output end of the three-terminal adjustable voltage stabilizer U1; the third capacitor C3 is connected in parallel with the seventh resistor R7.

Optionally, the overcharge judging subunit includes a first amplifier UTA, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourth capacitor C4, a first triode Q1, a second triode Q2, a first voltage relay J1, a second diode D2, and a charge indicator; one end of the fourth capacitor C4 is electrically connected to the second end of the input control subunit, and the other end of the fourth capacitor C4 is grounded; the positive input end of the first amplifier UTA is electrically connected to the second end of the solar charging input unit, and the negative input end of the first amplifier UTA is electrically connected to the other end of the eighth resistor R8; one end of the ninth resistor R9 is electrically connected to the positive input end of the first amplifier UTA, and the other end of the ninth resistor R9 is electrically connected to the output end of the first amplifier UTA; one end of the tenth resistor R10 is electrically connected to the output end of the first amplifier UTA, and the other end of the tenth resistor R10 is electrically connected to the base of the first triode Q1; one end of the eleventh resistor R11 and one end of the twelfth resistor R12 are electrically connected to the collector of the first triode Q1; the other end of the eleventh resistor R11 is electrically connected to the second end of the input control subunit; the other end of the twelfth resistor R12 is electrically connected to the base electrode of the second triode Q2; the emitter of the first triode Q1 and the emitter of the second triode Q2 are grounded; the collector electrode of the second triode Q2, the anode of the second diode D2 and the cathode of the charging indicator lamp are all electrically connected to one end of the first voltage relay J1; one end of the thirteenth resistor R13 is electrically connected to the positive electrode of the charge indicator lamp; the other end of the first voltage relay J1, the negative electrode of the second diode D2, and the other end of the thirteenth resistor R13 are all electrically connected to one end of the first relay contact J2-1.

Optionally, the over-discharge judging subunit includes a second amplifier UTB, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a third diode D3, a fourth diode D4, a third triode Q3, a fourth triode Q4, a second voltage relay J2, a third relay contact J2-2, a normal indicator lamp, and an over-discharge indicator lamp; the positive input end of the second amplifier UTB is electrically connected to the third end of the solar charging input unit, and the negative input end of the second amplifier UTB is electrically connected to the other end of the eighth resistor R8; the negative electrode of the third diode D3 is electrically connected to the other end of the eighth resistor R8, and the positive electrode of the third diode D3 is grounded; one end of the fourteenth resistor R14 is electrically connected to the positive input terminal of the second amplifier UTB, and the other end of the fourteenth resistor R14 is electrically connected to the output terminal of the second amplifier UTB; one end of the fifteenth resistor R15 is electrically connected to the output end of the second amplifier UTB, and the other end of the fifteenth resistor R15 is electrically connected to the base of the third triode Q3; one end of the sixteenth resistor R16 and one end of the seventeenth resistor R17 are electrically connected to the collector of the third triode Q3; the other end of the sixteenth resistor R16 is electrically connected to the second end of the input control subunit; the other end of the seventeenth resistor R17 is electrically connected to the base of the fourth triode Q4; the emitter of the third triode Q2 and the emitter of the fourth triode Q4 are grounded; the collector electrode of the fourth triode Q4, the anode of the fourth diode D4 and the cathode of the over-discharge indicator lamp are all electrically connected to one end of the second voltage relay J2; one end of the eighteenth resistor R18 is electrically connected to the positive electrode of the overdischarge indicator lamp; the other end of the second voltage relay J2, the negative electrode of the fourth diode D4, the other end of the eighteenth resistor R18 and one end of the third relay contact J2-2 are all electrically connected to one end of the first relay contact J2-1; one end of the nineteenth resistor R19 is electrically connected to the other end of the third relay contact J2-2, and the other end of the nineteenth resistor R19 is electrically connected to the positive electrode of the normal indicator lamp; and the negative electrode of the normal indicator lamp is grounded.

Optionally, the buck module includes a buck converter U2, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a fifth capacitor C5, an inductor L, and a fifth diode D5; one end of the solar charging control module is electrically connected with the input end of the buck converter U2; one end of the twentieth resistor R20 is electrically connected to one end of the solar charging control module, and the other end of the twentieth resistor R20 is electrically connected to an enable end of the buck converter U2; one end of the twenty-first resistor R21 and one end of the twenty-second resistor R22 are electrically connected to the feedback end of the buck converter U2; one end of the inductor L and the cathode of the fifth diode D5 are electrically connected to the output end of the buck converter U2; the positive electrode of the fifth capacitor C5 is electrically connected to the other end of the inductor L; the negative positive electrode of the fifth capacitor C5 and the positive electrode of the fifth diode D5 are both grounded.

Optionally, the voltage comparison module includes a first solar voltage input terminal VIN1, a second solar voltage input terminal VIN2, a first lithium battery voltage input terminal VBAT1, a second lithium battery voltage input terminal VBAT2, a voltage output terminal VOUT, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a fifth triode Q5, a sixth triode Q6, a MOS transistor M, a sixth diode D6, a seventh diode D7, a sixth capacitor C6, and a seventh capacitor C7; one end of the first solar voltage input end VIN1 and one end of the second solar voltage input end VIN2 are electrically connected to the other end of the voltage reduction module; one end of the first lithium battery voltage input end VBAT1 and one end of the second lithium battery voltage input end VBAT2 are electrically connected to the lithium battery module; one end of the twenty-third resistor R23 is electrically connected to the other end of the first solar voltage input terminal VIN1, and the other end of the twenty-third resistor R23 is electrically connected to the base of the fifth triode Q5; one end of the twenty-fourth resistor R24 and one end of the twenty-fifth resistor R25 are electrically connected to the collector of the fifth transistor Q5; the other end of the twenty-fourth resistor R24 and one end of the twenty-seventh resistor R27 are electrically connected to the other end of the first lithium battery voltage input terminal VBAT 1; the other end of the twenty-fifth resistor R25 and one end of the twenty-sixth resistor R26 are electrically connected to the base of the sixth triode Q6; the other end of the twenty-seventh resistor R27 is electrically connected to the collector of the sixth triode Q6; the other end of the second solar voltage input end VIN2 is electrically connected with the anode of the sixth diode D6; the other end of the second lithium battery voltage input end VBAT2 is electrically connected with the source electrode of the MOS tube M; the grid electrode of the MOS tube M is electrically connected with the collector electrode of the sixth triode Q6; the negative electrode of the sixth diode D6, the negative electrode of the seventh diode, the positive electrode of the sixth capacitor C6, one end of the seventh capacitor C7, and the drain electrode of the MOS transistor M are all electrically connected to the voltage output terminal VOUT; the emitter of the fifth transistor Q5, the emitter of the sixth transistor Q6, the other end of the twenty-sixth resistor R26, the positive electrode of the seventh diode, the negative electrode of the sixth capacitor C6, and the other end of the seventh capacitor C7 are all grounded.

A second aspect of the present application provides a battery and solar power control method based on a wireless transmitter, the method comprising: the voltage comparison module acquires a first voltage output by the voltage reduction module and judges whether the first voltage is smaller than a preset overdischarge voltage value or not; when the first voltage is smaller than the preset overdischarge voltage value, the solar charging control module is cut off to supply power to the load equipment, and the lithium battery module is conducted to supply power to the load equipment; and when the first voltage is not smaller than the preset overdischarge voltage value, the solar charging control module is conducted to supply power to the load equipment, and the lithium battery module is cut off to supply power to the load equipment.

In summary, one or more technical solutions provided in the embodiments of the present application at least have the following technical effects or advantages:

1. the solar charging control module is used for converting solar energy into a power supply voltage, so that the solar charging control module is used as a main power supply end for supplying power to the load equipment; the solar charging control module is electrically connected with the voltage reducing module, so that the voltage provided by the solar panel is reduced to a voltage level suitable for load equipment through the voltage reducing module and then transmitted to the voltage comparing module; and the voltage comparison module is used for reasonably determining a module for supplying power to the load equipment according to the input lithium battery voltage level and the voltage level of the solar battery after the voltage reduction.

2. The input control subunit may control and adjust the current and voltage input to the overcharge determination subunit and the overdischarge determination subunit. The overcharge and overdischarge determination unit may monitor charge and discharge states of the battery and ensure that the battery is not overcharged or overdischarged, thereby extending the life of the battery and improving the safety of the system.

Drawings

Fig. 1 is a schematic block diagram of a lithium battery and a solar power supply conversion circuit according to an embodiment of the present application;

fig. 2 is a schematic circuit diagram of a solar charging control module according to an embodiment of the present application;

fig. 3 is a schematic circuit diagram of a buck module according to an embodiment of the present disclosure;

FIG. 4 is a schematic circuit diagram of a voltage comparison module according to an embodiment of the present disclosure;

fig. 5 is a schematic flow chart of a conversion control method for lithium battery and solar power supply according to an embodiment of the present application.

Reference numerals illustrate: 1. a lithium battery module; 2. a solar charging control module; 21. a solar charging input unit; 22. an overcharge and overdischarge judging unit; 221. an input control subunit; 222. an overcharge judging subunit; 223. an overdischarge judgment subunit; 3. a buck module; 4. and the voltage comparison module.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present specification, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments.

In the description of embodiments of the present application, words such as "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described herein as "such as" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "or" for example "is intended to present related concepts in a concrete fashion.

In the description of the embodiments of the present application, the term "plurality" means two or more. For example, a plurality of systems means two or more systems, and a plurality of screen terminals means two or more screen terminals. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating an indicated technical feature. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "electrically connected," "electrically connected," or "electrically connected for communication" should be construed broadly, for example, "electrically connected," "electrically connected," or "electrically connected for communication" may mean not only physically electrically connected but also electrically connected or electrically connected for signals, for example, may be directly electrically connected, i.e., physically electrically connected, or may be indirectly electrically connected through at least one element in between, so long as electrical communication is achieved, or may be internal to two elements; signal electrical connection may refer to signal electrical connection through a medium, such as radio waves, in addition to signal electrical connection through a circuit. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

Referring to fig. 1, a schematic block diagram of a lithium battery and a solar power supply conversion circuit according to an embodiment of the present application is shown. Wherein the circuit comprises: a lithium battery module 1, a solar charging control module 2, a voltage reduction module 3 and a voltage comparison module 4; the lithium battery module 1 is electrically connected to a first end of the voltage comparison module 4; one end of the solar charging control module 2 is electrically connected with one end of the voltage reduction module 3, and the other end of the solar charging control module 2 is grounded; the other end of the voltage reduction module 3 is electrically connected with the second end of the voltage comparison module 4; the third terminal of the voltage comparison module 4 is electrically connected to the load device.

Specifically, in the present solution, the solar charging control module 2 is configured to convert solar energy into a voltage that can be supplied, so that the solar charging control module 2 serves as a main power supply terminal for supplying power to the load device. The solar charging control module 2 is electrically connected to the voltage reducing module 3, so that the voltage provided by the solar panel is reduced to a voltage level suitable for the load device by the voltage reducing module 3, and then transmitted to the voltage comparing module 4.

The voltage comparison module 4 determines a module for supplying power to the load device by the inputted lithium battery voltage and the stepped-down solar battery voltage.

That is, when the voltage comparison module 4 determines that the solar cell overdischarge voltage in the solar charging control module 2, that is, the solar cell voltage is smaller than the preset overdischarge voltage value, the solar charging control module 2 is turned off, and stops outputting the voltage continuously. At this time, the voltage comparison module 4 conducts a connection loop between the lithium battery module 1 and the voltage comparison module 4, coordinates a smooth transition of the lithium battery, and thus supplies power to the load device by using the lithium battery module 1.

When the recharging of the solar charging control module 2 is completed, that is, the voltage of the solar battery is greater than or equal to the preset overdischarge voltage value, the solar charging control module 2 is turned on again, and power supply for the load equipment is started. At this time, the voltage comparison module 4 disconnects the connection loop between the lithium battery module 1 and the voltage comparison module 4, so that the lithium battery module 1 stops supplying power to the load device.

In one possible embodiment, the solar charge control module 2 includes a solar charge input unit 21, an overcharge and overdischarge determination unit 22, and a first relay contact J2-1; one end of the solar charging input unit 21 is electrically connected to one end of the overcharge and overdischarge judging unit 22; the other end of the overcharge and overdischarge judging unit 22 is electrically connected to one end of the first relay contact J2-1; the other end of the first relay contact J2-1 is electrically connected to the step-down module 3.

Specifically, in the present embodiment, the solar charging input unit 21 is a part of the solar charging control module 2, and is responsible for receiving the electric energy input from the solar panel. One end of the solar energy power supply is electrically connected with one end of the overcharge and overdischarge judging unit 22, and the electric energy of the solar energy power supply is transmitted to the judging unit for processing.

The overcharge and overdischarge determination unit 22 is configured to monitor a charge state of the battery to avoid overcharge or overdischarge, thereby avoiding damage to the solar battery. The other end of which is connected to one end of the first relay contact J2-1, thereby controlling the state of the output voltage of the solar charge control module 2 through the relay.

When the solar battery is used for supplying power to the load equipment, the first relay contact J2-1 is in a normally closed state; when the electric quantity of the solar battery is insufficient and the lithium battery module 1 is used for supplying power to the load equipment, the first relay contact J2-1 is in a normally open state.

In one possible embodiment, the solar charging input unit 21 includes a solar panel T1, a first diode D1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a fuse FU, a first capacitor C1, a second capacitor C2, a stop-charge indicator, a battery T2, a second relay contact J1-1, and a switch K; the first end of the solar panel T1 is electrically connected with the anode of the first diode D1; the cathode of the first diode D1 is electrically connected to the first end of the second relay contact J1-1; one end of the first resistor R1 is electrically connected to the second end of the second relay contact J1-1, and the other end of the first resistor R1 is electrically connected to the positive electrode of the stop-charging indicator lamp; one end of the fuse FU is electrically connected to the third end of the second relay contact J1-1, and the other end of the fuse FU is electrically connected to the positive electrode of the storage battery T2; one end of the switch K is electrically connected to the third end of the second relay contact J1-1, and the other end of the switch K is electrically connected to one end of the second resistor R2 and one end of the third resistor R3; the third resistor R3 is connected in parallel with the first capacitor C1, and one end of the third resistor R3 and one end of the first capacitor C1 are both electrically connected to the other end of the second resistor R2; the fifth resistor R5 is connected in parallel with the second capacitor C2, and one end of the fifth resistor R5 and one end of the second capacitor C2 are both electrically connected to the other end of the fourth resistor R4; the second end of the solar panel T1, the negative electrode of the stop charge indicator lamp, the negative electrode of the storage battery T2, the other end of the third resistor, the other end of the first capacitor C1, the other end of the fifth resistor R5 and the other end of the second capacitor C2 are all grounded.

Specifically, in the present technical solution, referring to fig. 2, a schematic circuit diagram of a solar charging control module 2 provided in an embodiment of the present application is shown. When the solar panel T1 is irradiated by sunlight, the generated current passes through the normally-closed contact in the second relay contact J1-1 and then passes through the first resistor R1, so that the stop-charging indicator lamp is lighted. One end of the fuse FU is electrically connected to the third end of the second relay contact J1-1, and the other end of the fuse FU is electrically connected to the positive electrode of the storage battery T2 for protecting the circuit from over-current. The third resistor R3 is a sliding varistor connected in parallel with the first capacitor C1 for limiting the current, the first capacitor C1 for filtering and stabilizing the voltage. A fifth resistor R5 is connected in parallel with the second capacitor C2 for limiting the current.

The solar charge input unit 21 functions to receive power from the solar panel, limit current and stabilize voltage using a resistor and a capacitor, and prevent current backflow using the first diode D1. The stop-charging indicator lamp is used for displaying the charging state. The fuse FU is used to provide circuit protection, ensuring battery and circuit safety. The solar charging input unit 21 can effectively manage solar charging and ensure safe charging of the battery.

Wherein battery T2 is preferably a DC12v battery; the switch K is a button switch; the preferred resistance values of the first resistor R1, the third resistor R3 and the fifth resistor R5 are 10kΩ; the preferred resistance of the second resistor R2 and the fourth resistor R4 is 6.2kΩ; the rated current of the fuse FU is 2.2A; the preferred capacitance of the first capacitor C1 and the second capacitor C2 is 10 μf; the model of the first diode D1 is not excessively limited in this application.

In one possible embodiment, the overcharge and overdischarge determination unit 22 includes an input control subunit 221, an overcharge determination subunit 222, and an overdischarge determination subunit 223; a first terminal of the input control subunit 221 is electrically connected to a first terminal of the solar charging input unit 21; one end of the overcharge judging subunit 222 and one end of the overdischarge judging subunit 223 are electrically connected to the second end of the input control subunit 221.

Specifically, in the present embodiment, the input control subunit 221 is configured to control and adjust the current and voltage input to the overcharge determination subunit 222 and the overdischarge determination subunit 223. The overcharge and overdischarge determination unit 22 may monitor the charge and discharge states of the battery and ensure that the battery is not overcharged or overdischarged, thereby extending the life of the battery and improving the safety of the system.

In one possible embodiment, the input control subunit 221 includes a three-terminal adjustable voltage regulator U1, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a third capacitor C3; the input end of the three-end adjustable voltage stabilizer U1 is electrically connected with one end of the solar charging input unit 21; the control end of the three-end adjustable voltage stabilizer U1 is electrically connected with one end of a sixth resistor R6 and one end of a seventh resistor R7; the other end of the sixth resistor R6 and one end of the eighth resistor R8 are electrically connected to the output end of the three-terminal adjustable voltage stabilizer U1; the third capacitor C3 is connected in parallel with the seventh resistor R7.

Specifically, in the present embodiment, when the switch K is closed, the voltage output from the battery T2 is input to the input terminal of the three-terminal adjustable voltage regulator U1, i.e., the VI terminal of U1 as shown in fig. 2. At this time, the three-terminal adjustable voltage regulator U1 starts to operate, and adjusts the output voltage of the three-terminal adjustable voltage regulator U1 through the sixth resistor R6, the seventh resistor R7, and the third capacitor C3, so that the three-terminal adjustable voltage regulator U1 outputs 8v voltage through the output terminal, and transmits the 8v voltage to the overcharge judging subunit 222 and the overdischarge judging subunit 223 through the eighth resistor R8.

The preferable model of the three-terminal adjustable voltage stabilizer U1 is LM317; the preferred resistance value of the sixth resistor R6 is 200Ω; the seventh resistor R7 is a sliding resistor, which preferably has a resistance of 2kΩ; the preferred resistance value of the eighth resistor R8 is 2kΩ; the preferred capacitance of the third capacitor C3 is 10 μf.

In one possible embodiment, the overcharge judging subunit 222 includes a first amplifier UTA, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourth capacitor C4, a first transistor Q1, a second transistor Q2, a first voltage relay J1, a second diode D2, and a charge indicator light; one end of the fourth capacitor C4 is electrically connected to the second end of the input control subunit 221, and the other end of the fourth capacitor C4 is grounded; the positive input end of the first amplifier UTA is electrically connected to the second end of the solar charging input unit 21, and the negative input end of the first amplifier UTA is electrically connected to the other end of the eighth resistor R8; one end of the ninth resistor R9 is electrically connected to the positive input end of the first amplifier UTA, and the other end of the ninth resistor R9 is electrically connected to the output end of the first amplifier UTA; one end of the tenth resistor R10 is electrically connected to the output end of the first amplifier UTA, and the other end of the tenth resistor R10 is electrically connected to the base of the first transistor Q1; one end of the eleventh resistor R11 and one end of the twelfth resistor R12 are both electrically connected to the collector of the first transistor Q1; the other end of the eleventh resistor R11 is electrically connected to the second end of the input control subunit 221; the other end of the twelfth resistor R12 is electrically connected to the base of the second triode Q2; the emitter of the first triode Q1 and the emitter of the second triode Q2 are grounded; the collector electrode of the second triode Q2, the anode of the second diode D2 and the cathode of the charging indicator lamp are all electrically connected to one end of the first voltage relay J1; one end of the thirteenth resistor R13 is electrically connected to the positive electrode of the charge indicator lamp; the other end of the first voltage relay J1, the negative electrode of the second diode D2, and the other end of the thirteenth resistor R13 are all electrically connected to one end of the first relay contact J2-1.

Specifically, in the present embodiment, referring to fig. 2, the output voltage of the three-terminal adjustable voltage regulator U1 is input to the negative input terminal of the first amplifier UTA through the eighth resistor R8, and the output voltage of the battery T2 is input to the positive input terminal of the first amplifier UTA. When the voltage of the storage battery T2 is smaller than or equal to the voltage input to the negative input end of the first amplifier UTA, that is, smaller than or equal to the preset overcharge voltage value, the potential of the second pin of the first amplifier UTA is higher than that of the third pin, the output end of the UTA outputs a low potential to the base electrode of the first triode Q1, so that the first triode Q1 is turned off, and since the base electrode of the second triode Q2 is electrically connected to the collector electrode of the first triode Q1 through the twelfth resistor R12, the second triode Q2 is turned on at this time, so that the charge indicator lights are turned on, and the first voltage relay J1 acts, and the second relay contact J1-1 corresponding to the first voltage relay J1 is switched to a position, so that the solar panel T1 charges the storage battery T2.

When the electric quantity of the storage battery T2 is full, the voltage of the positive input end of the first amplifier UTA is greater than the voltage of the negative input end of the first amplifier UTA, at the moment, the potential of the second pin of the first amplifier UTA is lower than that of the third pin, the output end of UTA outputs high potential to the base electrode of the first triode Q1, so that the first triode Q1 is conducted, the second triode Q2 is cut off, the charging indicator is turned off, the first voltage relay J1 is released, the second relay contact J1-1 corresponding to the first voltage relay J1 is converted into an initial position, and the solar panel T1 stops charging the storage battery T2.

Wherein the preferred model of the first amplifier UTA is LM2904; the preferred resistance value of the ninth resistor R9 is 12kΩ, the preferred resistance value of the tenth resistor R10 is 10kΩ, the preferred resistance value of the eleventh resistor R11 is 10kΩ, the preferred resistance value of the twelfth resistor R12 is 10kΩ, and the preferred resistance value of the thirteenth resistor R13 is 10kΩ; the preferred capacitance of the fourth capacitor C4 is 100 μf; the types of the first triode Q1, the second triode Q2, the first voltage relay J1 and the second diode D2 are not excessively limited in the application.

In one possible embodiment, the over-discharge judging subunit 223 includes a second amplifier UTB, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a third diode D3, a fourth diode D4, a third transistor Q3, a fourth transistor Q4, a second voltage relay J2, a third relay contact J2-2, a normal indicator lamp, and an over-discharge indicator lamp; the positive input end of the second amplifier UTB is electrically connected to the third end of the solar charging input unit 21, and the negative input end of the second amplifier UTB is electrically connected to the other end of the eighth resistor R8; the cathode of the third diode D3 is electrically connected to the other end of the eighth resistor R8, and the anode of the third diode D3 is grounded; one end of the fourteenth resistor R14 is electrically connected to the positive input terminal of the second amplifier UTB, and the other end of the fourteenth resistor R14 is electrically connected to the output terminal of the second amplifier UTB; one end of the fifteenth resistor R15 is electrically connected to the output end of the second amplifier UTB, and the other end of the fifteenth resistor R15 is electrically connected to the base of the third transistor Q3; one end of the sixteenth resistor R16 and one end of the seventeenth resistor R17 are both electrically connected to the collector of the third transistor Q3; the other end of the sixteenth resistor R16 is electrically connected to the second end of the input control subunit 221; the other end of the seventeenth resistor R17 is electrically connected to the base of the fourth transistor Q4; the emitter of the third triode Q2 and the emitter of the fourth triode Q4 are grounded; the collector electrode of the fourth triode Q4, the positive electrode of the fourth diode D4 and the negative electrode of the over-discharge indicator lamp are all electrically connected to one end of the second voltage relay J2; one end of the eighteenth resistor R18 is electrically connected to the positive electrode of the over-discharge indicator lamp; the other end of the second voltage relay J2, the negative electrode of the fourth diode D4, the other end of the eighteenth resistor R18 and one end of the third relay contact J2-2 are electrically connected to one end of the first relay contact J2-1; one end of the nineteenth resistor R19 is electrically connected to the other end of the third relay contact J2-2, and the other end of the nineteenth resistor R19 is electrically connected to the positive electrode of the normal indicator lamp; the negative pole of normal pilot lamp ground connection.

Specifically, in the present embodiment, referring to fig. 2, the output voltage of the three-terminal adjustable voltage regulator U1 is input to the negative input terminal of the second amplifier UTB through the eighth resistor R8, and the output voltage of the battery T2 is input to the positive input terminal of the second amplifier UTB. When the voltage of the storage battery T2 is greater than the voltage input to the negative input end of the second amplifier UTB, that is, greater than the preset overdischarge voltage value, the voltage input to the positive input end of the second amplifier UTB is greater than the voltage input to the negative input end of the second amplifier UTB, at this time, the potential of the second pin of the second amplifier UTB is higher than the potential of the third pin, and the output end of the UTB outputs a high potential to the base electrode of the third triode Q3, so that the third triode Q3 is turned on, and the fourth triode Q4 is turned off. At this time, the second voltage relay J2 is released, the third relay contact J2-2 is closed, the first relay contact J2-1 is closed, and the normal indicator lamp is turned on, and at this time, the battery T2 normally outputs voltage to the step-down module 3.

Along with the continuous output voltage of the storage battery T2, when the voltage of the end of the storage battery T2 gradually decreases until the voltage of the storage battery T2 is smaller than or equal to the voltage input to the negative input end of the second amplifier UTB, that is, smaller than or equal to the preset overdischarge voltage value, the voltage input to the positive input end of the second amplifier UTB is smaller than the voltage input to the negative input end of the second amplifier UTB, at this time, the potential of the second pin of the second amplifier UTB is lower than the potential of the third pin, and the output end of the UTB outputs a low potential to the base electrode of the third triode Q3, so that the third triode Q3 is turned off, and the fourth triode Q4 is turned on. At the moment, the second voltage relay J2 acts, the third relay contact J2-2 is opened, the first relay contact J2-1 is opened, the normal indicator lamp is turned off, and at the moment, the storage battery T2 stops outputting voltage to the voltage reducing module 3, so that the storage battery T2 is prevented from being discharged continuously.

Wherein the preferred model of the second amplifier UTB is LM2904; the fourteenth resistor R14 has a preferred resistance of 13kΩ, the fifteenth resistor R15 has a preferred resistance of 10kΩ, the sixteenth resistor R16 has a preferred resistance of 10kΩ, the seventeenth resistor R17 has a preferred resistance of 10kΩ, the eighteenth resistor R18 has a preferred resistance of 10kΩ, and the nineteenth resistor R19 has a preferred resistance of 10kΩ; the types of the third diode D3, the fourth diode D4, the third triode Q3, the fourth triode Q4, and the second voltage relay J2 are not excessively limited in the present application.

In one possible embodiment, the buck module 3 includes a buck converter U2, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a fifth capacitor C5, an inductor L, and a fifth diode D5; one end of the solar charging control module 2 is electrically connected with the input end of the buck converter U2; one end of the twentieth resistor R20 is electrically connected to one end of the solar charge control module 2, and the other end of the twentieth resistor R20 is electrically connected to the enable end of the buck converter U2; one end of the twenty-first resistor R21 and one end of the twenty-second resistor R22 are electrically connected to the feedback end of the buck converter U2; one end of the inductor L and the cathode of the fifth diode D5 are electrically connected to the output end of the buck converter U2; the positive electrode of the fifth capacitor C5 is electrically connected to the other end of the inductor L; the negative positive electrode of the fifth capacitor C5 and the positive electrode of the fifth diode D5 are both grounded.

Specifically, in the present technical solution, referring to fig. 3, a schematic circuit diagram of a voltage step-down module 3 provided in an embodiment of the present application is shown. The buck converter U2 is used to reduce the input voltage of the solar charge control module 2 to a voltage level suitable for the load device, preferably to a voltage value of 5v suitable for the load device. The voltage output terminal of the solar charge control module 2, i.e., vcc terminal IN fig. 2, is electrically connected to the input terminal IN of the buck converter U2.

One end of the twentieth resistor R20 is connected to one end of the solar charge control module 2, and the other end is connected to an enable end of the buck converter U2 for enabling or disabling the buck converter U2. A twenty-first resistor R21 and a twenty-second resistor R22 are associated with the feedback terminal of the buck converter U2 for controlling the stability and regulation of the output voltage. The inductor L is used for storing energy and stabilizing the output voltage, one end of the inductor L is connected with the cathode of the fifth diode D5, and the other end of the inductor L is connected to the output end of the buck converter U2. The fifth capacitor C5 is for filtering and stabilizing the output voltage, and its positive electrode is connected to the other end of the inductor L. The fifth diode D5 is for controlling the current flow, and has a positive electrode connected to the negative electrode of the fifth capacitor C5, and a negative electrode connected to one end of the inductor L.

Through the circuit connection mode, the voltage of the solar charging control module 2 can be reduced to a voltage level suitable for load equipment, and the stability and the filtering effect of the output voltage are provided through the inductor and the capacitor, so that the load equipment can obtain a stable power supply.

Wherein the preferred model of buck converter U2 is SL3037B; the twentieth resistor R20 has a preferred resistance of 510kΩ, the twenty-first resistor R21 has a preferred resistance of 23.7kΩ, and the twenty-second resistor R22 has a preferred resistance of 127kΩ; the fifth capacitor C5 is preferably a polar capacitance, preferably having a capacitance of 22 μf; the preferred inductance value of inductor L is 47 μh; the preferred model of the fifth diode D5 is 1N5817.

In one possible embodiment, the voltage comparison module 4 includes a first solar voltage input VIN1, a second solar voltage input VIN2, a first lithium battery voltage input VBAT1, a second lithium battery voltage input VBAT2, a voltage output VOUT, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a fifth transistor Q5, a sixth transistor Q6, a MOS transistor M, a sixth diode D6, a seventh diode D7, a sixth capacitor C6, and a seventh capacitor C7; one end of the first solar voltage input end VIN1 and one end of the second solar voltage input end VIN2 are electrically connected to the other end of the voltage reduction module 3; one end of the first lithium battery voltage input end VBAT1 and one end of the second lithium battery voltage input end VBAT2 are electrically connected to the lithium battery module 1; one end of the twenty-third resistor R23 is electrically connected to the other end of the first solar voltage input terminal VIN1, and the other end of the twenty-third resistor R23 is electrically connected to the base of the fifth triode Q5; one end of the twenty-fourth resistor R24 and one end of the twenty-fifth resistor R25 are both electrically connected to the collector of the fifth transistor Q5; the other end of the twenty-fourth resistor R24 and one end of the twenty-seventh resistor R27 are both electrically connected to the other end of the first lithium battery voltage input terminal VBAT 1; the other end of the twenty-fifth resistor R25 and one end of the twenty-sixth resistor R26 are electrically connected to the base of the sixth triode Q6; the other end of the twenty-seventh resistor R27 is electrically connected to the collector of the sixth transistor Q6; the other end of the second solar voltage input end VIN2 is electrically connected with the anode of the sixth diode D6; the other end of the second lithium battery voltage input end VBAT2 is electrically connected with the source electrode of the MOS tube M; the grid electrode of the MOS tube M is electrically connected with the collector electrode of the sixth triode Q6; the cathode of the sixth diode D6, the cathode of the seventh diode, the anode of the sixth capacitor C6, one end of the seventh capacitor C7, and the drain of the MOS transistor M are all electrically connected to the voltage output terminal VOUT; the emitter of the fifth transistor Q5, the emitter of the sixth transistor Q6, the other end of the twenty-sixth resistor R26, the anode of the seventh diode, the cathode of the sixth capacitor C6, and the other end of the seventh capacitor C7 are all grounded.

Specifically, in the present technical solution, referring to fig. 4, a schematic circuit diagram of a voltage comparison module 4 provided in the present application is shown. When the battery T2 is in a charged state, the first solar voltage input terminal VIN1 and the second solar voltage input terminal VIN2 have no voltage, so the base voltage of the fifth transistor Q5 is 0, and the fifth transistor Q5 is turned off. The first lithium battery voltage input VBAT1 is divided by the twenty-fourth resistor R24 and the twenty-fifth resistor R25, and a voltage drop greater than 0.7V is generated at the base of the sixth transistor Q6, so that the sixth transistor Q6 is turned on. Because MOS pipe M is P channel type MOS pipe, and MOS pipe M's grid electricity is connected in the collecting electrode of sixth triode Q6, and the other end electricity of second lithium cell voltage input VBAT2 is connected in MOS pipe M's source, and MOS pipe M's grid department voltage is 0v this moment, and MOS pipe M's source voltage is lithium cell voltage, so MOS pipe M switches on. And because the MOS tube M generates little voltage drop when being conducted, the voltage of the output end VOUT is equal to the voltage of the lithium battery. At this time, the lithium battery outputs a voltage to the voltage output terminal VOUT.

When the electric quantity of the storage battery T2 is sufficient, the voltage of the first solar voltage input end VIN1 and the voltage of the second solar voltage input end VIN2 are larger than 1v, a voltage drop of 0.7v is generated at the base electrode of the fifth triode Q5, the fifth triode Q5 is conducted, the voltage drop of the base electrode of the sixth triode Q6 is 0, and the sixth triode Q6 is cut off. Therefore, at this time, the voltage of the gate of the MOS transistor M is at a high level, and Vgs >0, since the MOS transistor M is a P-channel MOS transistor, the MOS transistor M is turned off, and the lithium battery does not output voltage to the load device. At this time, the voltage of the battery T2 after the step-down is outputted to the voltage output terminal VOUT through the sixth diode D6.

Wherein the preferred resistance value of the twenty-third resistor R23 is 3.3kΩ, the preferred resistance value of the twenty-fourth resistor R24 is 10kΩ, the preferred resistance value of the twenty-fifth resistor R25 is 3.3kΩ, the preferred resistance value of the twenty-sixth resistor R26 is 100kΩ, and the preferred resistance value of the twenty-seventh resistor R27 is 1.5kΩ; the preferred model of the fifth transistor Q5 and the sixth transistor Q6 is S8050; the optimal model of the MOS tube M is A03401A; the preferred model of the sixth diode D6 is SS14; the preferred model of the seventh diode D7 is 1n5339B; the sixth capacitor C6 is preferably a polar capacitance, the capacitance value of which is preferably 10 μf; the preferred capacitance value of the seventh capacitor C7 is 100nF.

The embodiment of the present application further provides a method for controlling conversion of power supplied by a lithium battery and solar energy, which is applied to the circuit of any one of the above embodiments, referring to fig. 5, which shows a schematic flow diagram of the method for controlling conversion of power supplied by a lithium battery and solar energy, where the method includes steps S1 to S3:

step S1: the voltage comparison module acquires the first voltage output by the voltage reduction module and judges whether the first voltage is smaller than a preset overdischarge voltage value.

Step S2: when the first voltage is smaller than a preset overdischarge voltage value, the solar charging control module is cut off to supply power to the load equipment, and the lithium battery module is conducted to supply power to the load equipment.

Step S3: when the first voltage is not smaller than a preset overdischarge voltage value, the solar charging control module is conducted to supply power to the load equipment, and the lithium battery module is cut off to supply power to the load equipment.

The embodiment of the application provides a lithium battery and a solar power supply conversion device, which comprises a power supply circuit in any one of the embodiments.

It should be noted that: in the circuit provided in the above embodiment, when implementing the functions thereof, only the division of the above functional modules is used as an example, in practical application, the above functional allocation may be implemented by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules, so as to implement all or part of the functions described above. In addition, the circuit and method embodiments provided in the foregoing embodiments belong to the same concept, and detailed implementation processes of the circuit embodiments are shown in the circuit embodiments, which are not repeated herein.

A readable storage medium of a digital class meter, the readable storage medium of the digital class meter storing instructions. The digital class meter, when executed by one or more processors, is caused to perform a method as in one or more of the embodiments described above.

It should be noted that, for simplicity of description, the foregoing method embodiments are all expressed as a series of action combinations, but it should be understood by those skilled in the art that the present application is not limited by the order of actions described, as some steps may be performed in other order or simultaneously in accordance with the present application. Further, those skilled in the art will also appreciate that the embodiments described in the specification are all preferred embodiments, and that the acts and modules referred to are not necessarily required in the present application.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

In the several embodiments provided herein, it should be understood that the disclosed apparatus may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, such as a division of units, merely a division of logic functions, and there may be additional divisions in actual implementation, such as multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some service interface, device or unit indirect coupling or communication connection, electrical or otherwise.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable memory. Based on such understanding, the technical solution of the present application may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a memory, including several instructions for causing a computer device (which may be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the methods of the embodiments of the present application. And the aforementioned memory includes: various media capable of storing program codes, such as a U disk, a mobile hard disk, a magnetic disk or an optical disk.

The above are merely exemplary embodiments of the present disclosure and are not intended to limit the scope of the present disclosure. That is, equivalent changes and modifications are contemplated by the teachings of this disclosure, which fall within the scope of the present disclosure. Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains.

Claims

1. A lithium battery and solar power conversion circuit, the circuit comprising: the solar energy charging system comprises a lithium battery module (1), a solar energy charging control module (2), a voltage reducing module (3) and a voltage comparing module (4); the solar charging control module (2) comprises a solar charging input unit (21), an overcharge and overdischarge judging unit (22) and a first relay contact J2-1; the solar charging input unit (21) comprises a solar panel T1, a first diode D1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a fuse FU, a first capacitor C1, a second capacitor C2, a charging stop indicator light, a storage battery T2, a second relay contact J1-1 and a switch K; the overcharge and overdischarge judging unit (22) comprises an input control subunit (221), an overcharge judging subunit (222) and an overdischarge judging subunit (223); the input control subunit (221) includes a three-terminal adjustable voltage regulator U1, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a third capacitor C3; the overcharge judging subunit (222) includes a first amplifier UTA, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourth capacitor C4, a first triode Q1, a second triode Q2, a first voltage relay J1, a second diode D2, and a charge indicator; the over-discharge judging subunit (223) comprises a second amplifier UTB, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a third diode D3, a fourth diode D4, a third triode Q3, a fourth triode Q4, a second voltage relay J2, a third relay contact J2-2, a normal indicator lamp and an over-discharge indicator lamp; the voltage comparison module (4) comprises a first solar voltage input end VIN1, a second solar voltage input end VIN2, a first lithium battery voltage input end VBAT1, a second lithium battery voltage input end VBAT2, a voltage output end VOUT, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a fifth triode Q5, a sixth triode Q6, a MOS tube M, a sixth diode D6, a seventh diode D7, a sixth capacitor C6 and a seventh capacitor C7;

The lithium battery module (1) is electrically connected to a first end of the voltage comparison module (4);

one end of the solar charging control module (2) is electrically connected with one end of the voltage reduction module (3), and the other end of the solar charging control module (2) is grounded;

the other end of the voltage reduction module (3) is electrically connected with the second end of the voltage comparison module (4);

the third end of the voltage comparison module (4) is electrically connected with load equipment;

one end of the solar charging input unit (21) is electrically connected with one end of the overcharge and overdischarge judging unit (22);

the other end of the overcharge and overdischarge judging unit (22) is electrically connected to one end of the first relay contact J2-1;

the other end of the first relay contact J2-1 is electrically connected with the voltage dropping module (3);

the first end of the solar panel T1 is electrically connected to the anode of the first diode D1;

the cathode of the first diode D1 is electrically connected to the first end of the second relay contact J1-1;

one end of the first resistor R1 is electrically connected to the second end of the second relay contact J1-1, and the other end of the first resistor R1 is electrically connected to the positive electrode of the stop-charging indicator lamp;

one end of the fuse FU is electrically connected to the third end of the second relay contact J1-1, and the other end of the fuse FU is electrically connected to the positive electrode of the storage battery T2;

One end of the switch K is electrically connected to the third end of the second relay contact J1-1, and the other end of the switch K is electrically connected to one end of the second resistor R2 and one end of the third resistor R3;

the third resistor R3 is connected in parallel with the first capacitor C1, and one end of the third resistor R3 and one end of the first capacitor C1 are both electrically connected to the other end of the second resistor R2;

the fifth resistor R5 is connected in parallel with the second capacitor C2, and one end of the fifth resistor R5 and one end of the second capacitor C2 are both electrically connected to the other end of the fourth resistor R4;

the second end of the solar panel T1, the negative electrode of the stop-charge indicator lamp, the negative electrode of the storage battery T2, the other end of the third resistor, the other end of the first capacitor C1, the other end of the fifth resistor R5 and the other end of the second capacitor C2 are all grounded;

a first end of the input control subunit (221) is electrically connected to a first end of the solar charging input unit (21);

one end of the overcharge judging subunit (222) and one end of the overdischarge judging subunit (223) are electrically connected to the second end of the input control subunit (221);

The input end of the three-terminal adjustable voltage stabilizer U1 is electrically connected with one end of the solar charging input unit (21);

the control end of the three-terminal adjustable voltage stabilizer U1 is electrically connected with one end of the sixth resistor R6 and one end of the seventh resistor R7;

the other end of the sixth resistor R6 and one end of the eighth resistor R8 are electrically connected to the output end of the three-terminal adjustable voltage stabilizer U1;

the third capacitor C3 is connected in parallel with the seventh resistor R7;

one end of the fourth capacitor C4 is electrically connected to the second end of the input control subunit (221), and the other end of the fourth capacitor C4 is grounded;

the positive input end of the first amplifier UTA is electrically connected to the second end of the solar charging input unit (21), and the negative input end of the first amplifier UTA is electrically connected to the other end of the eighth resistor R8;

one end of the ninth resistor R9 is electrically connected to the positive input end of the first amplifier UTA, and the other end of the ninth resistor R9 is electrically connected to the output end of the first amplifier UTA;

one end of the tenth resistor R10 is electrically connected to the output end of the first amplifier UTA, and the other end of the tenth resistor R10 is electrically connected to the base of the first triode Q1;

One end of the eleventh resistor R11 and one end of the twelfth resistor R12 are electrically connected to the collector of the first triode Q1;

the other end of the eleventh resistor R11 is electrically connected to the second end of the input control subunit (221);

the other end of the twelfth resistor R12 is electrically connected to the base electrode of the second triode Q2;

the emitter of the first triode Q1 and the emitter of the second triode Q2 are grounded;

the collector electrode of the second triode Q2, the anode of the second diode D2 and the cathode of the charging indicator lamp are all electrically connected to one end of the first voltage relay J1;

one end of the thirteenth resistor R13 is electrically connected to the positive electrode of the charge indicator lamp;

the other end of the first voltage relay J1, the negative electrode of the second diode D2 and the other end of the thirteenth resistor R13 are electrically connected to one end of the first relay contact J2-1;

the positive input end of the second amplifier UTB is electrically connected to the third end of the solar charging input unit (21), and the negative input end of the second amplifier UTB is electrically connected to the other end of the eighth resistor R8;

the negative electrode of the third diode D3 is electrically connected to the other end of the eighth resistor R8, and the positive electrode of the third diode D3 is grounded;

One end of the fourteenth resistor R14 is electrically connected to the positive input terminal of the second amplifier UTB, and the other end of the fourteenth resistor R14 is electrically connected to the output terminal of the second amplifier UTB;

one end of the fifteenth resistor R15 is electrically connected to the output end of the second amplifier UTB, and the other end of the fifteenth resistor R15 is electrically connected to the base of the third triode Q3;

one end of the sixteenth resistor R16 and one end of the seventeenth resistor R17 are electrically connected to the collector of the third triode Q3;

the other end of the sixteenth resistor R16 is electrically connected to the second end of the input control subunit (221);

the other end of the seventeenth resistor R17 is electrically connected to the base of the fourth triode Q4;

the emitter of the third triode Q2 and the emitter of the fourth triode Q4 are grounded;

the collector electrode of the fourth triode Q4, the anode of the fourth diode D4 and the cathode of the over-discharge indicator lamp are all electrically connected to one end of the second voltage relay J2;

one end of the eighteenth resistor R18 is electrically connected to the positive electrode of the overdischarge indicator lamp;

the other end of the second voltage relay J2, the negative electrode of the fourth diode D4, the other end of the eighteenth resistor R18 and one end of the third relay contact J2-2 are all electrically connected to one end of the first relay contact J2-1;

One end of the nineteenth resistor R19 is electrically connected to the other end of the third relay contact J2-2, and the other end of the nineteenth resistor R19 is electrically connected to the positive electrode of the normal indicator lamp;

the negative electrode of the normal indicator lamp is grounded;

one end of the first solar voltage input end VIN1 and one end of the second solar voltage input end VIN2 are electrically connected to the other end of the voltage reduction module (3);

one end of the first lithium battery voltage input end VBAT1 and one end of the second lithium battery voltage input end VBAT2 are electrically connected to the lithium battery module (1);

one end of the twenty-third resistor R23 is electrically connected to the other end of the first solar voltage input terminal VIN1, and the other end of the twenty-third resistor R23 is electrically connected to the base of the fifth triode Q5;

one end of the twenty-fourth resistor R24 and one end of the twenty-fifth resistor R25 are electrically connected to the collector of the fifth transistor Q5;

the other end of the twenty-fourth resistor R24 and one end of the twenty-seventh resistor R27 are electrically connected to the other end of the first lithium battery voltage input terminal VBAT 1;

the other end of the twenty-fifth resistor R25 and one end of the twenty-sixth resistor R26 are electrically connected to the base of the sixth triode Q6;

The other end of the twenty-seventh resistor R27 is electrically connected to the collector of the sixth triode Q6;

the other end of the second solar voltage input end VIN2 is electrically connected with the anode of the sixth diode D6;

the other end of the second lithium battery voltage input end VBAT2 is electrically connected with the source electrode of the MOS tube M;

the grid electrode of the MOS tube M is electrically connected with the collector electrode of the sixth triode Q6;

the negative electrode of the sixth diode D6, the negative electrode of the seventh diode, the positive electrode of the sixth capacitor C6, one end of the seventh capacitor C7, and the drain electrode of the MOS transistor M are all electrically connected to the voltage output terminal VOUT;

the emitter of the fifth transistor Q5, the emitter of the sixth transistor Q6, the other end of the twenty-sixth resistor R26, the positive electrode of the seventh diode, the negative electrode of the sixth capacitor C6, and the other end of the seventh capacitor C7 are all grounded.

2. The circuit according to claim 1, characterized in that the buck module (3) comprises a buck converter U2, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a fifth capacitor C5, an inductor L and a fifth diode D5;

One end of the solar charging control module (2) is electrically connected with the input end of the buck converter U2;

one end of the twentieth resistor R20 is electrically connected to one end of the solar charging control module (2), and the other end of the twentieth resistor R20 is electrically connected to an enable end of the buck converter U2;

one end of the twenty-first resistor R21 and one end of the twenty-second resistor R22 are electrically connected to the feedback end of the buck converter U2;

one end of the inductor L and the cathode of the fifth diode D5 are electrically connected to the output end of the buck converter U2;

the positive electrode of the fifth capacitor C5 is electrically connected to the other end of the inductor L;

the negative positive electrode of the fifth capacitor C5 and the positive electrode of the fifth diode D5 are both grounded.

3. A conversion control method of lithium battery and solar power supply, characterized by being applied to the lithium battery and solar power supply conversion circuit according to any one of claims 1-2, the method comprising:

the voltage comparison module (4) acquires a first voltage output by the voltage reduction module (3) and judges whether the first voltage is smaller than a preset overdischarge voltage value or not;

when the first voltage is smaller than the preset overdischarge voltage value, the solar charging control module (2) is cut off to supply power to the load equipment, and the lithium battery module (1) is conducted to supply power to the load equipment;

When the first voltage is not smaller than the preset overdischarge voltage value, the solar charging control module (2) is conducted to supply power to the load equipment, and the lithium battery module (1) is cut off to supply power to the load equipment.