Solar charging control device, system and method

Abstract

The invention provides a solar charging control device, a solar charging control system and a solar charging control method, which are applied to the technical field of photovoltaic power generation and battery charging control. The battery information, including the battery type and the battery capacity, of the main battery is obtained, the preset threshold value is determined, in the charging process, the output voltage and the output current of the photovoltaic module are collected, the photovoltaic power is calculated, the photovoltaic power is matched with the battery information, the first output power is obtained, and when the deviation between the first output power and the preset threshold value is large, the first output power is output. The method comprises the following steps: performing adjustment by using a buffer module to obtain a second output power, determining a charging curve based on battery information, and adjusting the voltage or current of the second output power to match with the charging curve to obtain a third output power, thereby realizing dynamic matching between the photovoltaic power and the battery charging demand, and compared with a control scheme in the prior art, improving the control efficiency. And the charging efficiency is higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic power generation and battery charging control, and particularly relates to a solar charging control method, device and system based on matching of photovoltaic module power and battery characteristics. BACKGROUND

[0002] With the development of renewable energy, photovoltaic power generation technology is widely used in the field of solar energy utilization. The solar charging system is mainly used to convert and store the direct current power generated by the photovoltaic module into the storage battery or the main battery, and to provide stable power supply for various devices.

[0003] In the existing photovoltaic charging system, the charging control usually depends on the fixed power strategy or the simple maximum power point tracking (MPPT) strategy.

[0004] However, in the existing photovoltaic system, the control strategy mainly depends on the fixed power or the simple maximum power point tracking (MPPT) method. Since the fixed power strategy only charges according to the preset power, the type and capacity limit of the main battery are ignored, and although the simple MPPT method can maximize the photovoltaic power generation efficiency, the algorithm only tracks the maximum power point of the photovoltaic module, and lacks the mechanism of taking the parameters such as the state of charge and temperature of the main battery into account in the decision-making. Therefore, the type, capacity, state of charge and temperature information of the main battery cannot be effectively integrated into the charging control strategy, resulting in that the photovoltaic output power and the acceptable power of the battery cannot be matched, so that the problem of low charging efficiency is prone to occur in the charging process. SUMMARY

[0005] The present application provides a solar charging control device, system and control method, the core of which is that the battery information (type, capacity, state of charge and temperature) of the main battery is obtained, the photovoltaic power is calculated, and the control instruction is generated based on the photovoltaic power and the battery information, and the output power of the primary converter, the buffer module and the secondary converter is adjusted respectively; wherein the primary converter converts the photovoltaic module output into the preliminary charging power, the buffer module is used to smooth the instantaneous power fluctuation, and the secondary converter finally adjusts the output voltage or current, so that the final output power matches the charging curve, thereby improving the charging efficiency and protecting the safety of the battery.

[0006] To achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] The present application provides a solar charging control method, which can include:

[0008] Obtaining the battery information of the main battery, determining the corresponding preset threshold according to the battery information, and the battery information including the battery type and the battery capacity;

[0009] During the charging process, the output voltage and the output current of the photovoltaic module are collected, and the photovoltaic power is calculated according to the output voltage and the output current;

[0010] When the photovoltaic power changes, the corresponding first output current and the first output voltage are calculated by matching the photovoltaic power with the battery type and the battery capacity of the main battery, and the first output power provided to the main battery is obtained;

[0011] The first output power is compared with the preset threshold value, and when the deviation between the first output power and the preset threshold value exceeds the set deviation range, the deviation between the first output power and the preset threshold value is adjusted by using the buffer module to obtain the second output power;

[0012] Based on the battery information, the corresponding charging curve is determined, the output deviation between the second output current and the second output voltage corresponding to the second output power and the charging curve is calculated, and the second output current and the second output voltage corresponding to the second output power are adjusted according to the output deviation to obtain the third output power matched with the charging curve.

[0013] In some possible implementations, by matching the photovoltaic power with the battery type and the battery capacity of the main battery, the corresponding first output current and the first output voltage are calculated, and the first output power provided to the main battery is obtained, which can include:

[0014] The corresponding charging voltage and charging current are determined according to the battery type and the battery capacity of the main battery;

[0015] The output voltage of the photovoltaic power is matched with the charging voltage, and the first output voltage is calculated;

[0016] The output current of the photovoltaic power is matched with the charging current, the first output current is calculated, and the first output power provided to the main battery is obtained by multiplying the first output current and the first output voltage.

[0017] In some possible implementations, when the deviation between the first output power and the preset threshold value exceeds the set deviation range, the deviation between the first output power and the preset threshold value is adjusted by using the buffer module to obtain the second output power, which can include:

[0018] When the deviation between the first output power and the preset threshold value exceeds the set deviation range, the power deviation between the first output power and the preset threshold value is calculated to obtain a power correction amount;

[0019] Based on the power correction amount, the buffer module is controlled to adjust the first output power to obtain the second output power.

[0020] In some possible implementation manners, the adjusting, by the control buffer module, of the first output power based on the power correction amount to obtain the second output power can include:

[0021] generating a buffer adjustment signal based on the power correction amount, the buffer adjustment signal being used to limit a rate and a magnitude of the output power change;

[0022] controlling the buffer module by using the buffer adjustment signal to perform smooth adjustment on the first output power to obtain the second output power.

[0023] In some possible implementation manners, the output deviation includes a current deviation and a voltage deviation, and the battery information further includes state of charge information and temperature information, and the adjusting, according to the output deviation, of the second output current and the second output voltage corresponding to the second output power to obtain the third output power matching the charging curve includes:

[0024] taking absolute values of the voltage deviation and the current deviation as an adjustment magnitude factor and taking positive and negative signs of the voltage deviation and the current deviation as an adjustment direction, and determining a first adjustment coefficient based on the adjustment magnitude factor and the adjustment direction;

[0025] modifying the first adjustment coefficient according to the state of charge information and the temperature information of the main battery to obtain a second adjustment coefficient;

[0026] adjusting the second output current and the second output voltage of the second output power according to the second adjustment coefficient to output the third output power matching the charging curve.

[0027] In some possible implementation manners, the modifying of the first adjustment coefficient according to the state of charge and the temperature information of the main battery to obtain the second adjustment coefficient includes:

[0028] comparing the state of charge information of the main battery with a preset state of charge threshold, and when the state of charge information is higher or lower than the preset state of charge threshold, calculating a deviation between the state of charge information and the preset state of charge threshold to obtain a state of charge deviation amount;

[0029] comparing the temperature information of the main battery with a preset temperature threshold, and when the temperature information is higher or lower than the preset temperature threshold, calculating a deviation between the temperature information and the preset temperature threshold to obtain a temperature deviation amount;

[0030] generating a correction value according to the state of charge deviation amount and the temperature deviation amount according to a preset combination rule, and modifying the first adjustment coefficient based on the correction value to obtain the second adjustment coefficient.

[0031] In some possible implementation manners, the battery information of the main battery is acquired, and a corresponding preset threshold is determined according to the battery information, including:

[0032] acquire battery type, battery capacity, state of charge and temperature information of the main battery;

[0033] determine recommended charging power of the main battery according to the battery type and the battery capacity, adjust the recommended charging power through the state of charge and the temperature information of the main battery, and set the adjusted recommended charging power as a preset threshold corresponding to the main battery.

[0034] In some possible implementation manners, the method can further include: acquiring power point information of the photovoltaic module, comparing the power point information with the charging curve of the main battery, and determining a relative deviation between the power point information of the photovoltaic module and the charging curve of the main battery.

[0035] When the relative deviation exceeds a set range, the power point information of the photovoltaic module is corrected.

[0036] The power point information of the photovoltaic module includes a characteristic parameter representing a relationship between voltage, current and power of the photovoltaic module under different operating conditions.

[0037] The power point information includes operating voltage, operating current and output power of the photovoltaic module, and is used to represent a maximum power point position of the photovoltaic module and a deviation therefrom.

[0038] A solar charging control device, the device can include:

[0039] a controller module configured to acquire battery information of the main battery, and determine a corresponding preset threshold according to the battery information, the battery information including battery type and battery capacity;

[0040] During the charging process, output voltage and output current of the photovoltaic module are collected, and photovoltaic power is calculated according to the output voltage and the output current.

[0041] a primary converter module configured to, when the photovoltaic power changes, match the photovoltaic power with the battery type and the battery capacity of the main battery through the controller module, calculate a corresponding first output current and a first output voltage, and obtain a first output power provided to the main battery;

[0042] a buffer module configured to compare the first output power with the preset threshold, and when a deviation between the first output power and the preset threshold exceeds a set deviation range, adjust the deviation between the first output power and the preset threshold by using the buffer module to obtain a second output power;

[0043] a secondary converter module configured to determine a corresponding charging curve based on the battery information, calculate an output deviation between a second output current and a second output voltage corresponding to the second output power and the charging curve, and adjust the second output current and the second output voltage corresponding to the second output power according to the output deviation to obtain a third output power matched with the charging curve.

[0044] A solar charging control system can include a solar charging control device.

[0045] From the above technical solutions, the present application has the following beneficial effects:

[0046] 1. The present application constructs a hierarchical regulation charging control architecture, including a primary converter, a buffer module and a secondary converter, to realize dynamic matching of photovoltaic module output power and main battery charging demand. Compared with the prior art which only relies on fixed power or traditional MPPT method, photovoltaic energy can be efficiently and safely utilized, thereby improving the overall charging efficiency of the system.

[0047] 2. The present application constructs a composite regulation coefficient based on the battery type, battery capacity, state of charge SOC and temperature information of the main battery, to realize multi-parameter closed-loop fine control. Compared with the prior art which simply uses constant voltage and constant current charging method, overcharging, overdischarging and overheating phenomena can be effectively prevented while improving the charging speed, thereby prolonging the cycle life of the main battery.

[0048] 3. The present application constructs a cooperative control system to fit the photovoltaic side unstable power and the main battery charging curve. Compared with the prior art method which only optimizes photovoltaic power generation efficiency, dynamic cooperative control of the photovoltaic power generation end and the battery end is realized, a new charging strategy is provided, and the energy of photovoltaic power generation can be efficiently and safely utilized. BRIEF DESCRIPTION OF DRAWINGS

[0049] The present application will be further described below in conjunction with the drawings.

[0050] Figure 1 A flowchart of a solar charging control method provided by the present application is provided.

[0051] Figure 2 An example diagram of a solar charging control device provided by the present application is provided.

[0052] Figure 3 An example diagram of a solar charging control system provided by the present application is provided. DETAILED DESCRIPTION

[0053] The terms "first", "second" and "third" and the like in the specification and claims of the present application and in the description of the drawings are used to distinguish different objects, and are not used to limit a specific order.

[0054] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0055] To ensure clarity and conciseness in the description of the following embodiments, a brief introduction to the related technologies is given first:

[0056] Fixed power strategy: The system charges the battery at a preset constant power, typically without considering the real-time output capacity of the photovoltaic modules or the battery status. This strategy is simple to implement, but it can easily lead to low charging efficiency or overcharging and undercharging of the battery under conditions of varying sunlight or different battery capacities.

[0057] Maximum Power Point Tracking (MPPT) Strategy: The system dynamically adjusts the operating point of the photovoltaic (PV) module through algorithms to make the output power close to the maximum usable power of the PV module. MPPT can improve PV power generation efficiency, but the algorithm mainly focuses on the power generation characteristics of the PV module itself and usually does not incorporate the type, capacity, state of charge, and temperature information of the main cells into the control decision, resulting in insufficient matching between the PV output power and the acceptable power of the cells.

[0058] Research has revealed that existing photovoltaic (PV) systems primarily rely on fixed power or simple maximum power point tracking (MPPT) methods for control during charging. Fixed power strategies charge only at a preset power, ignoring the type and capacity limitations of the main battery. While the simple MPPT method maximizes PV power generation efficiency, its algorithm only tracks the maximum power point of the PV module, lacking a mechanism to incorporate parameters such as the main battery's state of charge (SOC) and temperature into the decision-making process. Therefore, the failure to effectively integrate the main battery's type, capacity, SOC, and temperature information into the charging control strategy leads to a mismatch between the PV output power and the battery's acceptable power, resulting in low charging efficiency during the charging process.

[0059] Example 1

[0060] To address the aforementioned problems, this application provides a solar charging control method. Please refer to [link / reference]. Figure 1 ;

[0061] In some possible implementations, detailed battery information of the main battery is acquired, including battery type, battery capacity, state of charge, and temperature information. The battery type is used to determine the chemical system of the main battery (such as lithium iron phosphate, ternary lithium, lead-acid battery, etc.), different types of batteries correspond to different charging characteristic curves, the battery capacity determines the maximum charging power range that the main battery can withstand, the state of charge information reflects the current power level of the battery, and determines whether high-power fast charging or low-power trickle charging is needed, and the temperature information is used to determine whether the battery is in a safe temperature range, for subsequent output power matching and adjustment;

[0062] On this basis, the recommended charging power is determined according to the battery type and battery capacity of the main battery. For example, a lithium battery with large capacity can withstand a large charging current at a low state of charge, while a lead-acid battery with small capacity needs a lower charging current. The recommended charging power can also be dynamically corrected by real-time acquisition of the state of charge information and the temperature information. When the battery is in a low state of charge and the temperature is suitable, the recommended charging power is allowed to be adjusted upward, and when the battery is close to a full state of charge or the temperature is close to the upper limit of the safety range, the recommended charging power is adjusted downward. The corrected recommended charging power is set as a preset threshold of the main battery, serving as a reference standard for subsequent power adjustment, to ensure that the charging process is carried out in a safe, stable, and efficient range. In order to ensure the reliability of the threshold, the threshold can also be dynamically corrected according to the historical charging and discharging data of the battery and the change of the environmental temperature, so as to adapt to the performance degradation of the battery in long-term operation or the change of environmental conditions;

[0063] During the charging process, the output voltage and output current of the photovoltaic module are acquired in real time, the current output power of the photovoltaic module is calculated by multiplication, and the power correction can also be performed by combining the environmental parameters (such as temperature and light intensity) of the photovoltaic module, to obtain a more accurate photovoltaic power value. Through continuous acquisition and calculation, the fluctuation of the power generation capacity of the photovoltaic module can be immediately grasped, to provide basic data for subsequent output power matching and adjustment;

[0064] When the photovoltaic power changes, the photovoltaic power is matched with the battery type and capacity of the main battery through a preset matching algorithm, to calculate the first output current and the first output voltage that can be accepted by the main battery. The photovoltaic power output by the photovoltaic module is adjusted to a preliminary charging range suitable for the main battery by using a first converter, to obtain the first output current and the first output voltage. The first output power corresponding to the first output current and the first output voltage is calculated and used as the preliminary charging power provided to the main battery. In this step, the constraint of the battery type on the charging characteristics is also considered, for example, different chemical systems of batteries have different sensitivities to current and voltage, so as to ensure that the preliminary charging power is compatible with the battery.

[0065] When the photovoltaic power appears short-time or instantaneous fluctuation, the first output power is compared with the preset threshold, and adjustment is performed only when the deviation between the first output power and the preset threshold exceeds the allowed range (too large or too small). The power correction amount is calculated, the buffer adjustment instruction is generated according to the power correction amount, the first output power is adjusted smoothly by using the buffer module, the buffer module limits the amplitude and rate of the output power change to prevent the short-time fluctuation of the photovoltaic power from directly acting on the main battery, and the impact or overheating on the battery is avoided. The adjustment process includes selecting the smooth adjustment rate according to the deviation size, so that the second output power is more stable while maintaining the charging safety.

[0066] The third output power is obtained by fine adjustment based on the charging curve. The charging curve of the battery is determined according to the type, capacity, state of charge and temperature information of the main battery, such as the constant current or constant voltage segmented strategy, and the voltage and current deviation between the second output power and the charging curve is calculated. The deviation size is used to determine the adjustment amplitude, and the direction of increasing or decreasing the current or voltage is judged according to the deviation direction, so as to generate the first adjustment coefficient. The first adjustment coefficient is modified according to the state of charge and temperature information of the main battery to form the second adjustment coefficient. The second adjustment coefficient is used for fine adjustment of the second output power, so that the output power is effectively matched with the charging curve. The above adjustment of the second output power is realized by using the secondary converter to obtain the third output power, and efficient charging is realized. In this step, the adjustment period and response speed of the second output power can be adjusted to cope with the rapid changes of the photovoltaic power and the battery state, so as to ensure the real-time and stability of the charging process.

[0067] During the whole charging process, the above adjustment process is executed in a loop, the photovoltaic module output, the main battery state and the environmental information are continuously monitored, and the output power is dynamically adjusted. At the same time, the key data (such as voltage, current, state of charge and temperature) in the charging process are recorded. These data can be used for subsequent charging strategy optimization, so that the charging process is self-adaptive to the battery performance degradation and environmental changes, and the charging efficiency and battery life are improved.

[0068] The embodiment realizes the effective fusion of the battery type, capacity, state of charge and temperature information in the charging control strategy by matching the photovoltaic output power and the charging demand of the main battery. The charging efficiency, stability and safety are effectively improved by combining the primary converter, the secondary converter and the buffer module and the smooth adjustment mechanism. Compared with the existing technology which depends on fixed power or simple MPPT method, the embodiment can adjust the charging process according to the actual photovoltaic power and the battery state, and realize the efficient charging control strategy.

[0069] Embodiment 2

[0070] In some possible implementation manners, the corresponding charging voltage and charging current are determined according to the battery type and the battery capacity of the main battery, the charging characteristic curve of different types of batteries is stored, the charging characteristic curve clearly specifies the optimal charging voltage range and the optimal charging current range under different battery capacities, when it is detected that the battery type of the main battery is a lithium battery, the characteristic curve corresponding to the lithium battery is called, and the target charging voltage and the target charging current suitable for the main battery are determined in combination with the capacity of the main battery, when it is detected that the battery type of the main battery is a lead-acid battery, the characteristic curve corresponding to the lead-acid battery is called, and the corresponding target charging voltage and target charging current are determined in combination with the battery capacity, in this way, the individualized charging voltage and charging current under different battery types and different capacities can be determined;

[0071] After the charging voltage and the charging current are determined, the output voltage of the photovoltaic power is compared with and matched with the charging voltage, when the output voltage of the photovoltaic power is higher than the charging voltage, the duty cycle is adjusted by using the first converter, so that the voltage at the output end gradually decreases until it is consistent with the target charging voltage, when the output voltage of the photovoltaic power is lower than the charging voltage, the output end voltage is raised by increasing the duty cycle, so that a stable state is reached in which the output voltage is matched with the target charging voltage, thereby obtaining a first output voltage, the output current of the photovoltaic power is matched with the charging current, when the output current of the photovoltaic power is greater than the charging current, the output end current is reduced by controlling the inductance current limiting function of the first converter, so that the output end current does not exceed the target charging current, when the output current of the photovoltaic power is less than the target charging current, the output end current is as close as possible to the target charging current by increasing the power conversion efficiency, after the process, a first output current that meets the charging requirement of the main battery is obtained;

[0072] Finally, the first output current and the first output voltage obtained above are multiplied to obtain a first output power provided to the main battery, in the above manner, not only can the voltage safety range and the current safety range of the main battery in the charging process be met, but also the utilization efficiency of the photovoltaic power can be significantly improved, and energy waste or battery loss caused by output mismatch can be avoided.

[0073] Embodiment 3

[0074] In some possible implementation manners, the buffer module is used to perform smooth adjustment on the first output power based on the calculated power correction amount when the deviation between the first output power of the photovoltaic assembly and the preset threshold value exceeds the allowed range (too large or too small), so as to generate a stable second output power, the design purpose of the buffer module is to solve the problem that the power of the photovoltaic assembly fluctuates rapidly with environmental factors such as light intensity and temperature, to avoid the fluctuation directly acting on the main battery, and to ensure the safety, stability and high efficiency of the charging process;

[0075] Specifically, by monitoring the first output power in real time and comparing it with the preset threshold, when the first output power is greater than the preset threshold and the deviation exceeds the allowed range (too large), it indicates that the instantaneous power supply capacity of the photovoltaic module exceeds the safe charging range that the main battery can currently withstand, at this time the difference between the two is calculated to obtain the power correction amount, when the first output power is less than the preset threshold and the deviation exceeds the allowed range (too small), it indicates that the demand of the main battery is higher than the instantaneous supply capacity of the photovoltaic module, and the difference is also calculated to obtain the corresponding power correction amount. The power correction amount not only reflects the size of the deviation, but also determines the adjustment strength and adjustment time required by the subsequent buffer module;

[0076] After obtaining the power correction amount, a buffer adjustment signal is generated based on the power correction amount, which is used to limit the rate of change of the first output power to avoid rapid adjustment that causes sharp fluctuations in battery port voltage and current. The above buffer adjustment signal acts on the buffer module, which absorbs part of the excess power through the inductive energy storage element when the first output power exceeds the preset threshold, and cooperates with the capacitor buffer unit to temporarily store the instantaneous high power, so that the power entering the main battery is peak clipping, thereby obtaining the reduced second output power, or when the first output power is lower than the preset threshold, the buffer module compensates by releasing the temporarily stored energy in the capacitor, so that the output power can still be maintained stable when the output power is insufficient for a short time, and the second output power output by the buffer module is closer to the preset threshold in value, and also maintains continuity and gradualness in change rate, thereby effectively avoiding the direct influence of rapid photovoltaic power fluctuations on the battery, ensuring the safety and life extension of the main battery during the entire charging process.

[0077] Embodiment 4

[0078] In some possible implementations, after obtaining the second output power by adjusting the buffer module, fine adjustment is performed based on the charging curve to obtain the third output power.

[0079] Specifically, by calculating the voltage deviation and current deviation between the second output power and the main battery charging curve in real time, the charging curve is determined according to the battery type and capacity of the main battery, for example, for a lithium battery, it can include a constant current charging phase, a constant voltage charging phase and a trickle charging phase. If the calculation result shows that there is a difference between the current second output voltage and the target voltage set by the charging curve, the difference is taken as the voltage deviation, and there is a difference between the current second output current and the target current of the charging curve, the difference is taken as the current deviation.

[0080] Then the absolute value of the voltage deviation and the current deviation is taken as the adjustment amplitude factor, reflecting the strength of the required adjustment, while the positive and negative value of the voltage deviation and the current deviation is taken as the adjustment direction, used to determine whether to increase or decrease the output current or output voltage, for example, when the actual voltage is lower than the target voltage, the symbol is negative, indicating that the output voltage needs to be increased, when the actual current is higher than the target current, the symbol is positive, indicating that the output current needs to be reduced, based on the adjustment amplitude factor and the adjustment direction, the first adjustment coefficient is formed;

[0081] On this basis, the state of charge information and the temperature information of the main battery are further introduced to modify the first adjustment coefficient to obtain the second adjustment coefficient. Specifically, the state of charge information of the main battery is compared with the preset charge threshold, when the state of charge information approaches the full charge threshold of the battery, the charge deviation amount is calculated, which is used to reduce the value of the first adjustment coefficient, so as to slow down the increase speed of the charging current, to avoid overvoltage or overheating caused by continuing high-speed charging at high state of charge. The temperature information of the main battery is compared with the preset temperature threshold, when the temperature information approaches the maximum working temperature allowed by the battery, the temperature deviation amount is calculated, which is used to further modify the first adjustment coefficient to reduce the growth amplitude of the output power, to avoid the risk of overheating. The above charge deviation amount and temperature deviation amount are weighted or superimposed according to the preset combination rule to generate a correction value, which is used to modify the first adjustment coefficient to obtain the second adjustment coefficient.

[0082] The above-mentioned second adjustment coefficient is a parameter basis for adjusting the second output power to obtain the third output power. By using the secondary converter, the second output voltage is gradually adjusted according to the amplitude and direction determined by the second adjustment coefficient, to obtain the third output voltage consistent with the target voltage of the charging curve. By using the secondary converter, the second output current is modified according to the second adjustment coefficient to obtain the third output current consistent with the target current of the charging curve. The final third output power not only considers the charging curve of the main battery in voltage or current, but also considers the state of charge information and temperature information of the main battery. Through the above-mentioned manner, the charging process can automatically slow down the charging rate when the battery approaches full charge state or is in high temperature state, to realize safety protection. When the battery is in low state of charge and the temperature is suitable, a higher charging power is allowed to realize the improvement of charging efficiency.

[0083] In some possible implementation manners, power point information of the photovoltaic module is acquired, the power point information includes characteristic parameters representing relationships between voltages, currents and powers of the photovoltaic module under different operating conditions, for example, a maximum power point voltage, a maximum power point current, and a current-voltage characteristic curve under different light intensities, during the charging process, the operating voltage, the operating current and the corresponding output power of the photovoltaic module are collected in real time to represent the maximum power point position of the current photovoltaic module and possible deviation, the power point information of the photovoltaic module is compared with the charging curve of the main battery, and a relative deviation therebetween is calculated, if the relative deviation is within a set range, it is indicated that the photovoltaic module output substantially matches the charging demand of the main battery, and no additional correction is needed, if the relative deviation exceeds the set range, for example, the actual operating point of the photovoltaic module deviates from the maximum power point obviously, or the output power is much higher than the bearing capacity of the main battery in the current state, the power point information of the photovoltaic module is corrected, and the correction manner includes: the operating voltage or current of the photovoltaic module is gradually adjusted by adjusting the control parameters of the converter, so that the output power point of the photovoltaic module returns to a target power close to the charging curve of the main battery, thereby reducing energy waste or charging risk caused by mismatch.

[0084] Embodiment 5

[0085] In some possible implementation manners, please refer to Figure 2 With Figure 3 The application provides a solar charging control device and a solar charging control system constructed based on the device.

[0086] The solar charging control device can include a controller module, a primary converter module, a buffer module and a secondary converter module.

[0087] Specifically, the controller module is the core unit of the solar charging control device, and the main functions include main battery information acquisition, photovoltaic power calculation, charging curve generation and control instruction issuing. The controller module acquires complete battery information of the main battery, including battery type, battery capacity, state of charge and temperature information, analyzes the battery type and capacity, calculates the recommended charging power of the main battery, dynamically corrects the recommended charging power in combination with the real-time state of charge and temperature information, and sets the corrected power as a preset threshold of the main battery, which is used for subsequent output power matching and adjustment.

[0088] During the charging process, the controller module collects the output voltage and output current of the photovoltaic module in real time, and obtains the actual output power of the photovoltaic module through calculation. In order to enhance the charging accuracy, the power can also be corrected in combination with the environmental parameters (such as light intensity and temperature) of the photovoltaic module, so as to obtain more accurate photovoltaic power data. The controller module compares the photovoltaic power with the main battery information, and comprehensively generates the hierarchical control instructions of the primary converter, the buffer module and the secondary converter, so as to ensure that the photovoltaic output power can dynamically adapt to the charging demand of the main battery.

[0089] The primary converter module receives the first control instruction issued by the controller module, and preliminarily adjusts the output of the photovoltaic module. Specifically, the module adjusts the output voltage and output current of the photovoltaic module, so that the photovoltaic output power is preliminarily matched with the bearable range of the main battery, thereby generating the first output power. The main role of this module is to adjust the fluctuating power of the photovoltaic module caused by environmental changes to a preliminary power range suitable for charging the main battery, and to provide basic data for subsequent buffer and smoothing adjustment. In the adjustment process, the primary converter will limit the output current or voltage according to the constraint conditions of the battery type and capacity, so as to ensure that the output power will not cause excessive impact or damage to the main battery.

[0090] The buffer module receives the output voltage and current corresponding to the first output power output by the primary converter, and adjusts the power deviation according to the second control instruction issued by the controller module.

[0091] Specifically, the controller module compares the first output power with the preset threshold of the main battery. When the deviation between the first output power and the preset threshold exceeds the set deviation range, the power deviation is calculated, and a buffer adjustment signal is generated according to the power deviation. The buffer module adjusts the first output power continuously and smoothly according to the buffer adjustment signal to obtain the second output power. This process effectively prevents the photovoltaic power from fluctuating directly on the main battery, and avoids adverse effects such as overcharging, overdischarging or instantaneous overcurrent of the battery.

[0092] The secondary converter module receives the output voltage and current corresponding to the second output power output by the buffer module, and finely adjusts according to the third control instruction issued by the controller module, so as to realize the third output power highly matched with the charging curve.

[0093] Specifically, the controller module calculates the deviation between the charging curve of the main battery and the output voltage and current corresponding to the second output power, judges the direction and amplitude of the voltage or current to be increased or decreased, and generates a preliminary adjustment coefficient. In combination with the state of charge and temperature information of the main battery, the preliminary adjustment coefficient is corrected to form a final adjustment coefficient. The secondary converter module finely adjusts the second output power according to the final adjustment coefficient to obtain the third output power matched with the charging curve.

[0094] The solar charging control system constructed based on the above device comprises a photovoltaic module, a main battery, a load and a solar charging control device, the photovoltaic module converts solar energy into direct current, the main battery is responsible for storing the photovoltaic generated power, and the solar charging control device is responsible for battery information collection, photovoltaic power calculation and hierarchical regulation control, realizing safe and efficient charging;

[0095] Specifically, during the system operation, the power output by the photovoltaic module is firstly subjected to preliminary matching by the first converter module, then subjected to smooth processing of power fluctuation by the buffer module, and finally subjected to fine adjustment by the second converter module to adjust the output power to the third output power matched with the charging curve, and charge the main battery, and the adjustment in the whole charging process is realized by calculating the corresponding adjustment value by the controller module, outputting the corresponding control instruction, and adjusting by the corresponding execution module, so that the type, capacity, state of charge and temperature information of the main battery are effectively integrated into the charging control strategy, the photovoltaic output power is matched with the acceptable power of the battery, and the charging process is realized.

[0096] The embodiment realizes the matching of the photovoltaic power and the demand of the main battery by effectively integrating the type, capacity, state of charge and temperature information of the main battery into the charging strategy through hierarchical control and modular design.

[0097] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application, and various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A solar charging control method, characterized by, The method comprises: acquiring battery information of a main battery, determining a corresponding preset threshold according to the battery information, the battery information comprising: battery type and battery capacity; in a charging process, collecting output voltage and output current of a photovoltaic module, calculating photovoltaic power according to the output voltage and the output current; when the photovoltaic power changes, matching the photovoltaic power with the battery type and the battery capacity of the main battery, calculating corresponding first output current and first output voltage, obtaining first output power provided to the main battery; comparing the first output power with the preset threshold, when the deviation between the first output power and the preset threshold exceeds a set deviation range, adjusting the deviation between the first output power and the preset threshold by using a buffer module, obtaining second output power; determining a corresponding charging curve based on the battery information, calculating output deviation between second output current and second output voltage corresponding to the second output power and the charging curve, adjusting the second output current and the second output voltage corresponding to the second output power according to the output deviation, obtaining third output power matched with the charging curve.

2. The method of claim 1, wherein, The method comprises: determining corresponding charging voltage and charging current according to the battery type and the battery capacity of the main battery; matching the output voltage of the photovoltaic power with the charging voltage, calculating the first output voltage; matching the output current of the photovoltaic power with the charging current, calculating the first output current, multiplying the first output current with the first output voltage, obtaining the first output power provided to the main battery.

3. The method of claim 1, wherein, The method comprises: when the deviation between the first output power and the preset threshold exceeds a set deviation range, calculating power deviation between the first output power and the preset threshold, obtaining a power correction amount; based on the power correction amount, controlling the buffer module to adjust the first output power, obtaining the second output power.

4. The method of claim 3, wherein, The method comprises: based on the power correction amount, generating a buffer adjustment signal, the buffer adjustment signal being used to limit the rate and amplitude of output power change; controlling the buffer module by the buffer adjustment signal, performing smooth adjustment on the first output power, obtaining the second output power.

5. The method of claim 1, wherein, The output deviation includes a current deviation and a voltage deviation, and the battery information further includes state of charge information and temperature information; and the adjusting the second output current and the second output voltage corresponding to the second output power according to the output deviation to obtain the third output power matching the charging curve includes: Taking absolute values of the voltage deviation and the current deviation as an adjustment amplitude factor and taking positive and negative signs of the voltage deviation and the current deviation as an adjustment direction, a first adjustment coefficient is determined based on the adjustment amplitude factor and the adjustment direction; The first adjustment coefficient is corrected according to the state of charge information and the temperature information of the main battery to obtain a second adjustment coefficient; The second output current and the second output voltage of the second output power are adjusted according to the second adjustment coefficient to output the third output power matching the charging curve.

6. The method of claim 5, wherein, The first adjustment coefficient is corrected according to the state of charge information and the temperature information of the main battery to obtain a second adjustment coefficient, and the method includes: The state of charge information of the main battery is compared with a preset state of charge threshold, and when the state of charge information is higher or lower than the preset state of charge threshold, a deviation between the state of charge information and the preset state of charge threshold is calculated to obtain a state of charge deviation amount; The temperature information of the main battery is compared with a preset temperature threshold, and when the temperature information is higher or lower than the preset temperature threshold, a deviation between the temperature information and the preset temperature threshold is calculated to obtain a temperature deviation amount; The state of charge deviation amount and the temperature deviation amount are combined according to a preset combination rule to generate a correction value, and the first adjustment coefficient is corrected based on the correction value to obtain a second adjustment coefficient.

7. The method of claim 1, wherein, The battery information of the main battery is acquired, and a corresponding preset threshold is determined according to the battery information, and the method includes: The battery type, the battery capacity, the state of charge information and the temperature information of the main battery are acquired; The recommended charging power of the main battery is determined according to the battery type and the battery capacity, and the recommended charging power is adjusted by the state of charge information and the temperature information of the main battery, and the adjusted recommended charging power is set as the preset threshold corresponding to the main battery.

8. The method of claim 1, wherein, Further including: The power point information of the photovoltaic module is acquired, the power point information is compared with the charging curve of the main battery, and a relative deviation between the power point information of the photovoltaic module and the charging curve of the main battery is determined; When the relative deviation exceeds a set range, the power point information of the photovoltaic module is corrected; The power point information of the photovoltaic module includes characteristic parameters representing relationships between voltages, currents and powers of the photovoltaic module under different operating conditions; The power point information includes operating voltages, operating currents and output powers of the photovoltaic module, and is used to represent a maximum power point position of the photovoltaic module and a deviation thereof.

9. A solar charging control device, characterized by, The device includes: A controller module is configured to acquire battery information of a main battery, and determine a corresponding preset threshold according to the battery information, wherein the battery information includes a battery type and a battery capacity. During the charging process, the output voltage and the output current of the photovoltaic module are collected, and the photovoltaic power is calculated according to the output voltage and the output current; The primary converter module is configured to match the photovoltaic power with the battery type and the battery capacity of the main battery through the controller module when the photovoltaic power changes, calculate the corresponding first output current and the first output voltage, and obtain the first output power provided to the main battery; The buffer module is configured to compare the first output power with the preset threshold value, adjust the deviation between the first output power and the preset threshold value when the deviation between the first output power and the preset threshold value exceeds a set deviation range, and obtain the second output power; The secondary converter module is configured to determine the corresponding charging curve based on the battery information, calculate the output deviation between the second output current and the second output voltage corresponding to the second output power and the charging curve, adjust the second output current and the second output voltage corresponding to the second output power according to the output deviation, and obtain the third output power matched with the charging curve.

10. A solar charging control system, characterized by, The system comprises the solar charging control device of claim 9.

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