A method for controlling the charging and discharging safety of a mobile power supply based on solar charging

Abstract

The present invention discloses a method for controlling the charging and discharging safety of a mobile power source based on solar charging, which relates to the field of power management technology, including: physically modeling a mobile power source charged by solar energy, and constructing an equivalent circuit of the mobile power source charged by solar energy; adopting a trickle-constant-current-constant-voltage charging method to charge a built-in storage battery of the mobile power source charged by solar energy; using a perturbation observation method to adjust the internal operating voltage of the mobile power source; adjusting the operating power of the storage battery to the maximum power point by adjusting the operating voltage of the storage battery, and providing a stable power supply for the output interface load; setting the operating state of a single-chip microcomputer based on whether there is a load at the output end; and setting a short-circuit and overcurrent protection mechanism in the charging and discharging circuit. By setting multiple circuit protection mechanisms, the stability and reliability of the power supply during the output process are ensured, thereby extending the service life of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of power management, and in particular to a method for safely controlling charging and discharging of a mobile power source based on solar charging. Background Art

[0002] In recent years, the market for mobile digital products such as mobile phones, tablet computers, and cameras has grown rapidly. Lithium batteries have been widely used in portable devices due to their advantages such as high single-cell voltage, large energy storage, long cycle life, and no memory. However, even high-capacity lithium batteries cannot avoid the trouble of charging once a day or even more than one day, which is particularly serious for outdoor workers and travelers. Mobile power supplies, as power supply devices that can achieve repeated charging and discharging, have begun to be favored by people. Solar mobile power supplies use solar energy to supplement electricity, and have the advantages of being pollution-free, clean, safe, low-priced, and widely applicable. It does not require ordinary city electricity, reduces operating costs, and can meet the requirements of green environmental protection.

[0003] Currently, there are only a few types of solar mobile power supplies on the market, and there are problems such as unstable voltage, low power conversion efficiency, and poor heat dissipation performance. Improvement and innovation are needed. How to combine efficient photovoltaic power generation technology with portable mobile power supplies is also a problem that needs to be solved. Summary of the invention

[0004] In order to solve the above technical problems, a method for safe control of charging and discharging of a mobile power supply based on solar charging is provided. This technical solution solves the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A method for safely controlling charging and discharging of a mobile power source based on solar charging, comprising:

[0007] Physical modeling of solar-powered mobile power supplies and construction of equivalent circuits of solar-powered mobile power supplies;

[0008] The trickle-constant current-constant voltage charging method is used to charge the built-in battery of the solar-powered mobile power supply;

[0009] The perturbation observation method is used to adjust the internal operating voltage of the mobile power supply, and the maximum power point of the solar-charged mobile power supply during discharge is tested and obtained;

[0010] Based on the DC-DC conversion circuit, the operating power of the battery is adjusted to the maximum power point by adjusting the operating voltage of the battery, providing a stable power supply for the output interface load;

[0011] Setting the operating state of the single-chip microcomputer based on whether there is a load at the output end, wherein the operating state includes a working state and a sleeping state;

[0012] Set up the timer program and determine whether the MCU clears the value in the timer within the preset time. If so, no output is made. If not, the MCU is reset.

[0013] Set up short-circuit and overcurrent protection mechanisms in the charging and discharging circuits. When abnormal current is detected, take immediate measures to cut off the circuit;

[0014] Temperature sensors are installed in the charging and discharging circuits to monitor the battery temperature in real time. When the temperature is higher than the preset threshold, the charging current is automatically adjusted or the discharging circuit is cut off.

[0015] Preferably, the physical modeling of the solar-powered mobile power source and the construction of an equivalent circuit of the solar-powered mobile power source specifically include:

[0016] Solar cells convert sunlight energy directly into electrical energy. When sunlight shines on a solar cell, the photons excite the electrons inside the cell, generating solar current.

[0017] When an electrical device is connected to both ends of the battery, an operating voltage will be formed in the electrical device. The direction of the operating voltage is opposite to the voltage of the solar cell, and the operating current generated by the operating voltage is opposite to the direction of the solar current.

[0018] Connect a diode in parallel at both ends of the running current and record the magnitude of the reverse saturation current in the diode;

[0019] In the equivalent circuit of the mobile power supply, a resistor is connected in parallel and in series to replace the energy loss of the mobile power supply during use;

[0020] Based on the basic circuit theory, the equivalent circuit formula is used to express the quantitative relationship between the operating current and the operating voltage;

[0021] The equivalent circuit formula is:

[0022]

[0023] Where, I is the operating current, I p is the solar current, I s is the reverse saturation current in the diode, q is the charge carried by the electron, U is the operating voltage, R1 is the series resistance, K is the Boltzmann constant, T is the absolute temperature of the solar cell, and R2 is the parallel resistance.

[0024] Preferably, the trickle-constant current-constant voltage charging method is used to charge the built-in storage battery of the solar-charged mobile power supply, specifically including:

[0025] In the initial stage of charging, a trickle charge method is used to pre-treat the deeply discharged battery through a low current charging mode;

[0026] Determine whether the operating voltage of the built-in battery of the solar-powered mobile power source is higher than the voltage threshold. If so, a constant current charging method is adopted to increase the operating current by adjusting the impedance of the series resistor and the parallel resistor, and charge at a constant operating current. If not, no output is made;

[0027] Use the state of charge formula to calculate the real-time state of charge of the built-in battery of the solar-powered mobile power supply;

[0028] Determine whether the real-time state of charge of the battery is higher than the state of charge threshold. If so, the charging mode is changed to constant voltage charging, and the operating current is reduced by adjusting the impedance of the series resistor and the parallel resistor, and charging is performed at a constant operating voltage. If not, no output is made;

[0029] The state of charge formula is:

[0030]

[0031] In the formula, SOC is the real-time state of charge of the battery, Q m is the rated charge capacity of the battery, Q n is the remaining charge capacity of the battery.

[0032] Preferably, the method of adjusting the internal operating voltage of the mobile power supply by using the perturbation observation method to test and obtain the maximum power point of the mobile power supply charged by solar energy during discharge specifically includes:

[0033] Place the solar power bank in the sun so that it receives constant solar radiation;

[0034] Set an initial voltage value as the starting point of the perturbation and observation method;

[0035] On the basis of the initial voltage value, increase or decrease the operating voltage according to the preset step size, and record the adjusted operating voltage and operating current values;

[0036] Calculate the current operating power according to the product of the operating voltage and the operating current value, and compare it with the operating power adjusted last time;

[0037] Determine whether the current power is greater than the previous power. If so, the output adjustment direction is correct, calculate the operating power increase rate, and continue to adjust the operating voltage value in this direction. If not, the output adjustment direction is wrong, and the operating voltage value is adjusted in the opposite direction;

[0038] Determine whether the operating power increase rate is lower than the preset increase rate threshold. If so, output the current operating power as the maximum power point and stop adjusting. If not, no output is made.

[0039] Preferably, the DC-to-DC conversion circuit adjusts the operating power of the battery to the maximum power point by adjusting the operating voltage of the battery to provide a stable power supply for the output interface load, specifically including:

[0040] When the transistor is turned on, the energy of the first capacitor is released through the second inductor, the second capacitor and the impedance loop, and energy is stored in the second inductor and the second capacitor at the same time;

[0041] When the transistor is turned off, the current on the first inductor flows through the diode and charges the first capacitor at the same time;

[0042] Based on the switching time of the transistor, the duty cycle of the switching signal is calculated;

[0043] Substituting the duty cycle of the switching signal into the transformer formula, the quantitative relationship between the operating voltage before and after adjustment is obtained;

[0044] The duty cycle is:

[0045]

[0046] Where D is the duty cycle of the switching signal, t on is the conduction time of the transistor, t off is the closing time of the transistor;

[0047] The transformer formula is:

[0048]

[0049] Wherein, U0 is the operating voltage value before adjustment, and U1 is the operating voltage value after adjustment.

[0050] Preferably, the step of setting the operating state of the single-chip microcomputer based on whether there is a load at the output terminal specifically includes:

[0051] When the microcontroller detects that there is no load on the output, it enters a sleep state with a power consumption lower than the preset value;

[0052] When a load connection is detected, the microcontroller wakes up from sleep mode and enters normal working mode, adjusting the output voltage and current according to the load requirements.

[0053] Preferably, the step of setting a timer program and determining whether the single chip microcomputer clears the value in the timer within a preset time specifically includes:

[0054] Initialize timer registers;

[0055] Set the timer's timing and start the timer;

[0056] During the timer startup period, the operation data of the mobile power supply is recorded in real time;

[0057] When the timer overflows, the microcontroller generates an interrupt signal and detects the running data recorded in the timer;

[0058] Determine whether the value in the timer is 0. If so, no output is made. If not, the operating status of the microcontroller is reset and the timer is restarted.

[0059] Preferably, the short circuit and overcurrent protection mechanisms are provided in the charging and discharging circuits, and when an abnormal current is detected, measures are immediately taken to cut off the circuit, specifically including:

[0060] Providing a short circuit detection circuit in the charging and discharging circuits;

[0061] The overcurrent protection mechanism monitors the current value in the circuit in real time through the current transformer;

[0062] Determine whether the current value in the circuit exceeds the preset current threshold. If so, output that the current circuit is an overcurrent circuit. If not, no output is made.

[0063] The short-circuit protection mechanism monitors the voltage conditions in the circuit in real time;

[0064] Determine whether the current growth rate in the circuit is greater than a preset growth rate threshold and the voltage drop rate is higher than a preset drop rate threshold. If so, output that the current circuit is a short circuit; if not, no output is made;

[0065] When a short circuit or overcurrent circuit is detected, the fuse activates immediately and cuts off the power supply.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] Physical modeling of solar-charged mobile power supplies and construction of their equivalent circuits help to more accurately understand and analyze the working principles and performance of mobile power supplies, and provide a theoretical basis for charging strategy design, circuit optimization, and troubleshooting. The DC-to-DC conversion circuit ensures the stability and adaptability of the power supply under different load conditions by adjusting the operating voltage of the battery, thereby improving the utilization and efficiency of the power supply. Setting short-circuit and over-current protection mechanisms in the charging and discharging circuits can monitor the current conditions in the circuit in real time, thus avoiding safety issues such as circuit damage or fire caused by excessive current or short circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1This is a flow chart of the charging and discharging safety control method of a mobile power source based on solar charging of the present invention;

[0069] Figure 2 A flow chart of a method for physically modeling a mobile power source for solar charging according to the present invention;

[0070] Figure 3 A flow chart of a method for charging a built-in storage battery of a solar-powered mobile power source of the present invention;

[0071] Figure 4 This is a flow chart of a method for adjusting the internal operating voltage of a mobile power supply using a perturbation observation method according to the present invention;

[0072] Figure 5 A flow chart of a method for adjusting the operating voltage of a battery to adjust the operating power of the battery to the maximum power point according to the present invention;

[0073] Figure 6 A flow chart of a method for setting the operating state of a single-chip microcomputer based on whether or not there is a load at an output terminal according to the present invention;

[0074] Figure 7 A flow chart of a method for setting a timer program and determining whether a single-chip microcomputer clears the value in the timer within a preset time according to the present invention;

[0075] Figure 8 The present invention is a flow chart of the method for setting short circuit and overcurrent protection mechanisms in charging and discharging circuits. DETAILED DESCRIPTION

[0076] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0077] Reference Figure 1 As shown, a method for safely controlling charging and discharging of a mobile power source based on solar charging comprises:

[0078] Physical modeling of solar-powered mobile power supplies and construction of equivalent circuits of solar-powered mobile power supplies;

[0079] The trickle-constant current-constant voltage charging method is used to charge the built-in battery of the solar-powered mobile power supply;

[0080] The perturbation observation method is used to adjust the internal operating voltage of the mobile power supply, and the maximum power point of the solar-charged mobile power supply during discharge is tested and obtained;

[0081] Based on the DC-DC conversion circuit, the operating power of the battery is adjusted to the maximum power point by adjusting the operating voltage of the battery, providing a stable power supply for the output interface load;

[0082] Setting the operating state of the single-chip microcomputer based on whether there is a load at the output end, wherein the operating state includes a working state and a sleeping state;

[0083] Set up the timer program and determine whether the MCU clears the value in the timer within the preset time. If so, no output is made. If not, the MCU is reset.

[0084] Set up short-circuit and overcurrent protection mechanisms in the charging and discharging circuits. When abnormal current is detected, take immediate measures to cut off the circuit;

[0085] Temperature sensors are installed in the charging and discharging circuits to monitor the battery temperature in real time. When the temperature is higher than the preset threshold, the charging current is automatically adjusted or the discharging circuit is cut off.

[0086] Reference Figure 2 As shown, physical modeling of the solar-powered mobile power supply and construction of an equivalent circuit of the solar-powered mobile power supply specifically include:

[0087] Solar cells convert sunlight energy directly into electrical energy. When sunlight shines on a solar cell, the photons excite the electrons inside the cell, generating solar current.

[0088] When an electrical device is connected to both ends of the battery, an operating voltage will be formed in the electrical device. The direction of the operating voltage is opposite to the voltage of the solar cell, and the operating current generated by the operating voltage is opposite to the direction of the solar current.

[0089] Connect a diode in parallel at both ends of the running current and record the magnitude of the reverse saturation current in the diode;

[0090] In the equivalent circuit of the mobile power supply, a resistor is connected in parallel and in series to replace the energy loss of the mobile power supply during use;

[0091] Based on the basic circuit theory, the equivalent circuit formula is used to express the quantitative relationship between the operating current and the operating voltage;

[0092] The equivalent circuit formula is:

[0093]

[0094] Where, I is the operating current, I p is the solar current, I s is the reverse saturation current in the diode, q is the charge carried by the electron, U is the operating voltage, R1 is the series resistance, K is the Boltzmann constant, T is the absolute temperature of the solar cell, and R2 is the parallel resistance.

[0095] As an energy capture unit for mobile power sources, the core function of solar cells is to convert sunlight energy directly into electrical energy. When sunlight shines on the surface of solar cells, photons interact with electrons inside the solar cell material, stimulating electron transitions and generating current. This process is called the photovoltaic effect. In physical modeling, solar cells can be regarded as a current source, and the output current is affected by the light intensity and the characteristics of the solar cell itself. At the same time, solar cells also exhibit diode-like characteristics, that is, when a load is connected to both ends of the battery, an operating voltage opposite to the solar cell voltage will be generated, and the operating current generated by the operating voltage is opposite to the solar cell current.

[0096] Reference Figure 3 As shown, the trickle-constant current-constant voltage charging method is used to charge the built-in battery of the solar-powered mobile power supply, which specifically includes:

[0097] In the initial stage of charging, a trickle charge method is used to pre-treat the deeply discharged battery through a low current charging mode;

[0098] Determine whether the operating voltage of the built-in battery of the solar-powered mobile power source is higher than the voltage threshold. If so, a constant current charging method is adopted to increase the operating current by adjusting the impedance of the series resistor and the parallel resistor, and charge at a constant operating current. If not, no output is made;

[0099] Use the state of charge formula to calculate the real-time state of charge of the built-in battery of the solar-powered mobile power supply;

[0100] Determine whether the real-time state of charge of the battery is higher than the state of charge threshold. If so, the charging mode is changed to constant voltage charging, and the operating current is reduced by adjusting the impedance of the series resistor and the parallel resistor, and charging is performed at a constant operating voltage. If not, no output is made;

[0101] The state of charge formula is:

[0102]

[0103] In the formula, SOC is the real-time state of charge of the battery, Q m is the rated charge capacity of the battery, Q n is the remaining charge capacity of the battery.

[0104] In the initial stage of charging, since polarization may exist inside the deeply discharged battery, directly charging with a large current may cause damage to the battery. Therefore, a trickle charging method is used in this stage to pre-treat the battery through a small current charging mode; after the trickle charging pre-treatment, it is necessary to determine whether the operating voltage of the built-in battery of the solar-charged mobile power supply is higher than the set voltage threshold. If it is higher than the voltage threshold, it enters the constant current charging stage, and the operating current is increased by adjusting the impedance of the series resistor and the parallel resistor, and charging is performed at a constant operating current; when the real-time state of charge of the battery is higher than the set state of charge threshold, the charging method is changed to constant voltage charging. At this time, the operating current is reduced by adjusting the impedance of the series resistor and the parallel resistor, and charging is performed at a constant operating voltage; through the above-mentioned trickle-constant current-constant voltage charging method, the built-in battery of the solar-charged mobile power supply can be effectively charged to ensure the safety and charging efficiency of the battery.

[0105] Reference Figure 4 As shown, the perturbation observation method is used to adjust the internal operating voltage of the mobile power supply, and the maximum power point of the mobile power supply charged by solar energy during discharge is tested and obtained. Specifically, the following are included:

[0106] Place the solar power bank in the sun so that it receives constant solar radiation;

[0107] Set an initial voltage value as the starting point of the perturbation and observation method;

[0108] On the basis of the initial voltage value, increase or decrease the operating voltage according to the preset step size, and record the adjusted operating voltage and operating current values;

[0109] Calculate the current operating power according to the product of the operating voltage and the operating current value, and compare it with the operating power adjusted last time;

[0110] Determine whether the current power is greater than the previous power. If so, the output adjustment direction is correct, calculate the operating power increase rate, and continue to adjust the operating voltage value in this direction. If not, the output adjustment direction is wrong, and the operating voltage value is adjusted in the opposite direction;

[0111] Determine whether the operating power increase rate is lower than the preset increase rate threshold. If so, output the current operating power as the maximum power point and stop adjusting. If not, no output is made.

[0112] Place the solar mobile power supply outdoors or in an environment with stable solar radiation to ensure that it can receive continuous and constant solar radiation. This is the prerequisite for using the perturbation observation method to adjust the operating voltage and test the maximum power point. The step size and increase rate threshold of the perturbation observation method should be flexibly adjusted according to actual conditions to balance the test accuracy and test time. During the test, pay close attention to the temperature changes of the mobile power supply to avoid performance degradation or damage due to overheating.

[0113] Reference Figure 5 As shown, based on the DC-DC conversion circuit, the operating power of the battery is adjusted to the maximum power point by adjusting the operating voltage of the battery, and a stable power supply is provided for the output interface load, specifically including:

[0114] When the transistor is turned on, the energy of the first capacitor is released through the second inductor, the second capacitor and the impedance loop, and energy is stored in the second inductor and the second capacitor at the same time;

[0115] When the transistor is turned off, the current on the first inductor flows through the diode and charges the first capacitor at the same time;

[0116] Based on the switching time of the transistor, the duty cycle of the switching signal is calculated;

[0117] Substituting the duty cycle of the switching signal into the transformer formula, the quantitative relationship between the operating voltage before and after adjustment is obtained;

[0118] The duty cycle is:

[0119]

[0120] Where D is the duty cycle of the switching signal, t on is the conduction time of the transistor, t off is the closing time of the transistor;

[0121] The transformer formula is:

[0122]

[0123] Wherein, U0 is the operating voltage value before adjustment, and U1 is the operating voltage value after adjustment.

[0124] The transistor is used as a switching element to control the on and off of the circuit. The first inductor is used to store energy. When the transistor is turned on, the power supply charges the first inductor through the transistor. The second inductor and the second capacitor together constitute an output filter circuit for smoothing the output voltage. The first capacitor is used as an energy storage element. When the transistor is turned off, the first capacitor is charged through the diode to prepare for the next transistor conduction. The impedance loop is used to limit the current and protect the components in the circuit.

[0125] Reference Figure 6 As shown in the figure, the operation status of the microcontroller is set based on whether there is a load at the output end, including:

[0126] When the microcontroller detects that there is no load on the output, it enters a sleep state with a power consumption lower than the preset value;

[0127] When a load connection is detected, the microcontroller wakes up from sleep mode and enters normal working mode, adjusting the output voltage and current according to the load requirements.

[0128] The solar mobile power supply uses a single-chip microcomputer to realize intelligent operating status setting based on whether there is a load on the output end. When there is no load, the single-chip microcomputer enters a low-power mode to extend the use time; when there is a load, it wakes up quickly and provides a stable power supply. This design not only improves the intelligence and automation of the mobile power supply, but also provides users with a more convenient and reliable outdoor power solution.

[0129] Reference Figure 7 As shown, setting the timer program and judging whether the microcontroller clears the value in the timer within the preset time specifically includes:

[0130] Initialize timer registers;

[0131] Set the timer's timing and start the timer;

[0132] During the timer startup period, the operation data of the mobile power supply is recorded in real time;

[0133] When the timer overflows, the microcontroller generates an interrupt signal and detects the running data recorded in the timer;

[0134] Determine whether the value in the timer is 0. If so, no output is made. If not, the operating status of the microcontroller is reset and the timer is restarted.

[0135] When setting the timer, you need to ensure that the overflow time of the timer meets the actual needs to avoid problems caused by the timer overflowing too quickly or too slowly. In the interrupt service program, you need to handle the interrupt signal correctly and ensure that the state of the variable can correctly reflect the state of the timer. In the main program, you need to reasonably arrange the execution frequency of the loop and the timing of the clearing operation to ensure that the microcontroller can work normally.

[0136] Reference Figure 8 As shown, short-circuit and overcurrent protection mechanisms are set in the charging and discharging circuits. When abnormal current is detected, measures are taken immediately to cut off the circuit. Specifically, the following are performed:

[0137] Providing a short circuit detection circuit in the charging and discharging circuits;

[0138] The overcurrent protection mechanism monitors the current value in the circuit in real time through the current transformer;

[0139] Determine whether the current value in the circuit exceeds the preset current threshold. If so, output that the current circuit is an overcurrent circuit. If not, no output is made.

[0140] The short-circuit protection mechanism monitors the voltage conditions in the circuit in real time;

[0141] Determine whether the current growth rate in the circuit is greater than a preset growth rate threshold and the voltage drop rate is higher than a preset drop rate threshold. If so, output that the current circuit is a short circuit; if not, no output is made;

[0142] When a short circuit or overcurrent circuit is detected, the fuse activates immediately and cuts off the power supply.

[0143] The single-chip microcomputer collects the battery status and current value in real time to realize an intelligent and automated protection mechanism. When abnormal current is detected, the single-chip microcomputer controls the LED to display the current status and sends out an alarm signal to alert the user.

[0144] Furthermore, the present solution also proposes a computer-readable storage medium on which a computer-readable program is stored. When the computer-readable program is called, the above-mentioned mobile power supply charging and discharging safety control method based on solar charging is executed.

[0145] It is understandable that the storage medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; an optical medium, such as a DVD; or a semiconductor medium, such as a solid state drive (SSD).

[0146] In summary, the advantages of the present invention are: physical modeling of the solar-charged mobile power supply and construction of its equivalent circuit help to more accurately understand and analyze the working principle and performance of the mobile power supply, and provide a theoretical basis for charging strategy design, circuit optimization and troubleshooting. The DC-to-DC conversion circuit ensures the stability and adaptability of the power supply under different load conditions by adjusting the operating voltage of the battery, thereby improving the utilization and efficiency of the power supply. Short-circuit and over-current protection mechanisms are set in the charging and discharging circuits, which can monitor the current conditions in the circuit in real time, avoiding safety problems such as circuit damage or fire caused by excessive current or short circuit.

[0147] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for controlling the safe charging and discharging of a mobile power source based on solar charging, characterized in that: include: Physical modeling of solar-powered mobile power supplies and construction of equivalent circuits of solar-powered mobile power supplies; The trickle-constant current-constant voltage charging method is used to charge the built-in battery of the solar-powered mobile power supply; The perturbation observation method is used to adjust the internal operating voltage of the mobile power supply, and the maximum power point of the solar-charged mobile power supply during discharge is tested and obtained; Based on the DC-DC conversion circuit, the operating power of the battery is adjusted to the maximum power point by adjusting the operating voltage of the battery, providing a stable power supply for the output interface load; Setting the operating state of the single-chip microcomputer based on whether there is a load at the output end, wherein the operating state includes a working state and a sleeping state; Set up the timer program and determine whether the MCU clears the value in the timer within the preset time. If so, no output is made. If not, the MCU is reset. Set up short-circuit and overcurrent protection mechanisms in the charging and discharging circuits. When abnormal current is detected, take immediate measures to cut off the circuit; Temperature sensors are installed in the charging and discharging circuits to monitor the battery temperature in real time. When the temperature is higher than the preset threshold, the charging current is automatically adjusted or the discharging circuit is cut off.

2. According to claim 1, a method for controlling charging and discharging safety of a mobile power source based on solar charging is characterized in that: The physical modeling of the solar-powered mobile power source and the construction of an equivalent circuit of the solar-powered mobile power source specifically include: Solar cells convert sunlight energy directly into electrical energy. When sunlight shines on a solar cell, the photons excite the electrons inside the cell, generating solar current. When an electrical device is connected to both ends of the battery, an operating voltage will be formed in the electrical device. The direction of the operating voltage is opposite to the voltage of the solar cell, and the operating current generated by the operating voltage is opposite to the direction of the solar current. Connect a diode in parallel at both ends of the running current and record the magnitude of the reverse saturation current in the diode; In the equivalent circuit of the mobile power supply, a resistor is connected in parallel and in series to replace the energy loss of the mobile power supply during use; Based on the basic circuit theory, the equivalent circuit formula is used to express the quantitative relationship between the operating current and the operating voltage; The equivalent circuit formula is: Where, I is the operating current, I p is the solar current, I s is the reverse saturation current in the diode, q is the charge carried by the electron, U is the operating voltage, R1 is the series resistance, K is the Boltzmann constant, T is the absolute temperature of the solar cell, and R2 is the parallel resistance.

3. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 2, characterized in that: The trickle-constant current-constant voltage charging method is used to charge the built-in storage battery of the solar-powered mobile power supply, which specifically includes: In the initial stage of charging, a trickle charge method is used to pre-treat the deeply discharged battery through a low current charging mode; Determine whether the operating voltage of the built-in battery of the solar-powered mobile power source is higher than the voltage threshold. If so, a constant current charging method is adopted to increase the operating current by adjusting the impedance of the series resistor and the parallel resistor, and charge at a constant operating current. If not, no output is made; Use the state of charge formula to calculate the real-time state of charge of the built-in battery of the solar-powered mobile power supply; Determine whether the real-time state of charge of the battery is higher than the state of charge threshold. If so, the charging mode is changed to constant voltage charging, and the operating current is reduced by adjusting the impedance of the series resistor and the parallel resistor, and charging is performed at a constant operating voltage. If not, no output is made; The state of charge formula is: In the formula, SOC is the real-time state of charge of the battery, Q m is the rated charge capacity of the battery, Q n is the remaining charge capacity of the battery.

4. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 3, characterized in that: The method of using the perturbation observation method to adjust the internal operating voltage of the mobile power supply and test and obtain the maximum power point of the mobile power supply charged by solar energy during discharge specifically includes: Place the solar power bank in the sun so that it receives constant solar radiation; Set an initial voltage value as the starting point of the perturbation and observation method; On the basis of the initial voltage value, increase or decrease the operating voltage according to the preset step size, and record the adjusted operating voltage and operating current values; Calculate the current operating power based on the product of the operating voltage and the operating current value, and compare it with the operating power adjusted last time; Determine whether the current power is greater than the previous power. If so, the output adjustment direction is correct, calculate the operating power increase rate, and continue to adjust the operating voltage value in this direction. If not, the output adjustment direction is wrong, and the operating voltage value is adjusted in the opposite direction; Determine whether the operating power increase rate is lower than the preset increase rate threshold. If so, output the current operating power as the maximum power point and stop adjusting. If not, no output is made.

5. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 4, characterized in that: The DC-to-DC conversion circuit is based on adjusting the operating voltage of the battery to adjust the operating power of the battery to the maximum power point, and providing a stable power supply for the output interface load specifically includes: When the transistor is turned on, the energy of the first capacitor is released through the second inductor, the second capacitor and the impedance loop, and energy is stored in the second inductor and the second capacitor at the same time; When the transistor is turned off, the current on the first inductor flows through the diode and charges the first capacitor at the same time; Based on the switching time of the transistor, the duty cycle of the switching signal is calculated; Substituting the duty cycle of the switching signal into the transformer formula, the quantitative relationship between the operating voltage before and after adjustment is obtained; The duty cycle is: Where D is the duty cycle of the switching signal, t on is the conduction time of the transistor, t off is the closing time of the transistor; The transformer formula is: Wherein, U0 is the operating voltage value before adjustment, and U1 is the operating voltage value after adjustment.

6. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 5, characterized in that: The step of setting the operating state of the single-chip microcomputer based on whether there is a load at the output terminal specifically includes: When the microcontroller detects that there is no load on the output, it enters a sleep state with a power consumption lower than the preset value; When a load connection is detected, the microcontroller wakes up from sleep mode and enters normal working mode, adjusting the output voltage and current according to the load requirements.

7. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 6, characterized in that: The step of setting a timer program and determining whether the single chip microcomputer clears the value in the timer within a preset time specifically includes: Initialize timer registers; Set the timer's timing and start the timer; During the timer startup period, the operation data of the mobile power supply is recorded in real time; When the timer overflows, the microcontroller generates an interrupt signal and detects the running data recorded in the timer; Determine whether the value in the timer is 0. If so, no output is made. If not, the operating status of the microcontroller is reset and the timer is restarted.

8. A method for controlling charging and discharging safety of a mobile power source based on solar charging according to claim 7, characterized in that: The short circuit and overcurrent protection mechanisms are set in the charging and discharging circuits, and when an abnormal current is detected, measures are immediately taken to cut off the circuit, specifically including: Providing a short circuit detection circuit in the charging and discharging circuits; The overcurrent protection mechanism monitors the current value in the circuit in real time through the current transformer; Determine whether the current value in the circuit exceeds the preset current threshold. If so, output that the current circuit is an overcurrent circuit. If not, no output is made. The short-circuit protection mechanism monitors the voltage conditions in the circuit in real time; Determine whether the current growth rate in the circuit is greater than a preset growth rate threshold and the voltage drop rate is higher than a preset drop rate threshold. If so, output that the current circuit is a short circuit; if not, no output is made; When a short circuit or overcurrent circuit is detected, the fuse activates immediately and cuts off the power supply.

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