Charging and discharging protection method of high-voltage energy storage all-in-one machine based on application scene

Abstract

The invention relates to the field of charging and discharging protection methods for energy storage equipment, in particular to a charging and discharging protection method for a high-voltage energy storage all-in-one machine based on an application scene, which comprises the following steps of: pre-judging an application scene range according to set parameters of the high-voltage energy storage all-in-one machine, and forming a charging and discharging protection strategy template according to the application scene range; storing in a battery management system of the high-voltage energy storage all-in-one machine; detecting surrounding environment parameters in real time, and carrying out charging and discharging protection on the high-voltage energy storage all-in-one machine according to a charging and discharging protection strategy corresponding to the real-time application scene; and dynamically calculating and correcting a protection threshold value in real time according to the environmental parameters, and using the corrected protection threshold value for the battery management system to carry out charge and discharge control. Charging and discharging protection can be carried out according to an application scene, and the charging and discharging safety of equipment is improved.

Description

Technical Field

[0001] This invention relates to the field of charging and discharging protection methods for energy storage devices, and more specifically to a charging and discharging protection method for a high-voltage integrated energy storage device based on an application scenario. Background Technology

[0002] With the advancement of dual-carbon goals and the transformation of the energy structure, electrochemical energy storage systems, especially high-voltage integrated energy storage units, are widely used in scenarios such as home energy storage, commercial buildings, small factories, emergency power supplies, and integrated photovoltaic-storage-charging power stations due to their advantages of high energy density, high integration, and convenient installation. These diverse application scenarios place higher demands on the safety, reliability, and adaptability of energy storage systems.

[0003] The charging and discharging process is the core of an energy storage system's operation and also the most prone to safety risks. Overcharging, over-discharging, overcurrent, overheating, and battery inconsistencies can all lead to battery performance degradation, shortened lifespan, and even serious safety accidents such as thermal runaway, fire, and explosion. Therefore, protecting high-voltage energy storage devices during the charging and discharging process is crucial.

[0004] Currently, the mainstream charging and discharging protection methods for high-voltage energy storage integrated machines are mainly based on the internal parameters of the battery itself (such as single cell / total voltage, current, temperature, and internal resistance) to make threshold judgments. The system sets fixed voltage, current, and temperature protection thresholds, and when the real-time monitoring data exceeds or falls below these thresholds, it triggers corresponding protection actions (such as power reduction or circuit disconnection).

[0005] However, existing fixed-threshold protection methods have poor adaptability to different application scenarios due to the vastly different load characteristics, operating modes, safety redundancy requirements, and grid interaction needs of residential and commercial settings. For example, residential scenarios prioritize the economy and quiet operation of charging during off-peak hours and discharging during peak hours, while commercial scenarios may focus more on the ability to continuously output high power and real-time matching with photovoltaic power generation. Existing fixed strategies cannot optimize charge and discharge boundaries according to scenario characteristics, which may lead to overly conservative approaches in commercial scenarios (affecting profitability) or failure to fully utilize dynamic electricity price windows in residential scenarios (affecting economic efficiency). Insufficient consideration of environmental and climatic factors: The operational safety of energy storage systems is strongly correlated with the surrounding environment (e.g., installation in basements, garages, or outdoors) and climatic conditions (e.g., ambient temperature, humidity, altitude). In high-temperature environments, batteries are more prone to overheating, requiring stricter temperature protection thresholds and more aggressive cooling strategies; in low-temperature environments, charging acceptance decreases, and if a normal-temperature charging strategy is still used, lithium deposition can easily lead to internal short circuits. Most existing technologies only use ambient temperature as a secondary reference or employ simple seasonal mode switching, lacking a sophisticated and proactive protection mechanism that comprehensively considers temperature, humidity, and ventilation conditions. Safety, economy, and availability are difficult to balance: while the most conservative fixed threshold strategy maximizes safety, it severely limits the available capacity and regulation capabilities of the energy storage system, reducing return on investment. Users or operators often need to manually trade off between safety and performance, lacking an intelligent system that can automatically achieve optimal operation within safety boundaries. Summary of the Invention

[0006] The present invention aims to provide a charging and discharging protection method for a high-voltage energy storage integrated machine based on application scenarios, so as to solve the problem of poor environmental adaptability of existing equipment during charging and discharging.

[0007] The charging and discharging protection method for the high-voltage energy storage integrated machine based on the application scenario in this solution includes the following steps: Step 1: Based on the setting parameters of the high-voltage energy storage unit, predict the application scenario range, and form a charging and discharging protection strategy template according to the application scenario range, and store it in the battery management system of the high-voltage energy storage unit. Step 2: Real-time detection of surrounding environmental parameters, including ambient temperature, humidity, and altitude; determination of the corresponding real-time application scenario based on the environmental parameters; and implementation of charging and discharging protection for the high-voltage energy storage unit according to the charging and discharging protection strategy corresponding to the real-time application scenario. Step 3: Dynamically calculate and correct the protection threshold in real time based on environmental parameters. The protection threshold includes the maximum charging current and the dynamic maximum allowable temperature. The corrected protection threshold is used by the battery management system for charge and discharge control.

[0008] Preferably, in order to ensure the charging and discharging safety of the high-voltage energy storage unit in a very few extreme environments, in step 1, the charging and discharging protection strategy template includes an extreme scenario charging and discharging adjustment strategy. The extreme scenario charging and discharging adjustment strategy includes: under low temperature conditions, performing a preheating operation on the battery pack for a preset time before charging. The preset time is set according to the preheating method. During charging and discharging, the charging parameters and discharging parameters are limited to a preset range. Under high temperature conditions, enhanced cooling and charging parameter limits are implemented before and during charging, and the discharge parameters are limited to a set range during discharge.

[0009] Preferably, in order to dynamically and accurately determine the charging and discharging environment of the high-voltage energy storage unit in real time, the environmental parameters in step 2 also include environmental images. The temperature change trend in the real-time application scenario is determined in real time based on the environmental images, humidity, and altitude. The temperature change trend includes stable, drastic, and smooth.

[0010] Preferably, in order to ensure that the threshold calculation and correction can be used as a control basis in a timely manner and improve the safety of the high-voltage energy storage unit, in step 3, the theoretical temperature rise limit is first predicted in real time based on the charging time and the amount to be charged, and then the temperature rise limit is obtained by increasing or decreasing the set value of the theoretical temperature rise limit in combination with environmental parameters.

[0011] Preferably, in order to automatically calculate the protection threshold and dynamically adapt to changes in the application environment, the formula for calculating the maximum charging current is: C_charge_max_dynamic=min(C_chemistry,C_thermal,C_life); Where C_chemistry is the electrochemical limiting current; C_thermal is the thermal limiting current; and C_life is the lifetime limiting current.

[0012] Preferably, in order to achieve a balance between charging speed and lifespan during the charging process, and to control the rate of heat generation and chemical reaction during the charging process, in step 3, a maximum thermal limit current C_thermal is calculated to control the charging process. The calculation formula is: C_thermal=f(Q_max_cooling,T_env_pred,ΔT_to_Tmax), where T_env_pred is the predicted ambient temperature, and ΔT_to_Tmax is the temperature difference to reach the upper limit of the dynamic temperature.

[0013] More preferably, to ensure that the cell temperature does not exceed the safe range under the predicted future temperature rise path, the thermal limiting current is calculated as follows: a. Predict the ambient temperature for a future period based on environmental parameters and generate a predicted ambient temperature curve T_env(t). Input the predicted ambient temperature curve T_env(t) for a future period. b. Input the corrected maximum cooling capacity of the current cooling system, Q_max_cooling; c. Perform iterative calculations of the thermal model using the current current to predict T_cell_pred(t); d. Reverse solution: Find the maximum constant current value C_thermal such that within the predicted time window (such as the next charging segment), T_cell_pred(t) <= T_max_dynamic - ΔT_margin, where ΔT_margin is the safety margin.

[0014] More preferably, the formula for calculating the maximum allowable dynamic temperature T_max_dynamic is: T_max_dynamic=min(T_safety,T_life); Where T_safety is the hard safety boundary; T_life is the economic life boundary.

[0015] More preferably, to improve the accuracy of predicted ambient temperature, the type of temperature change in the application scenario is first determined. This type of temperature change includes stable indoor temperature, gradual indoor temperature, gradual outdoor temperature, and rapid outdoor temperature. Then, the ambient temperature is predicted by combining environmental parameters and the type of temperature change. When the temperature change type is stable indoor temperature, a prediction within a preset range is made based on the temperature in the environmental parameters. When the temperature change type is gradual indoor temperature, the predicted ambient temperature is made according to a preset trend based on the temperature in the environmental parameters. When the temperature change type is gradual outdoor temperature, the prediction is made according to the seasonal trend based on the temperature in the environmental parameters. When the temperature change type is rapid outdoor temperature, the prediction is made according to the historical degree of temperature change based on the temperature in the environmental parameters.

[0016] Compared with existing technologies, the beneficial effects of this solution are: By predicting the scope of application scenarios and storing the corresponding charge and discharge protection strategy templates in the device, core objectives for each scenario can be pre-set, such as prioritizing economy, reliability, and battery life. This enables efficient and rapid protection measures during the charge and discharge process. In actual control, the device determines the real-time application scenario based on real-time environmental parameters and performs corresponding charge and discharge protection. Simultaneously, it dynamically calculates and corrects protection thresholds, allowing for dynamic adjustment of protection thresholds based on environmental conditions. This makes charge and discharge protection control more adaptable to environmental changes and improves the effectiveness of device protection control. Attached Figure Description

[0017] Figure 1 This is a schematic block diagram of an embodiment of the charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario. Detailed Implementation

[0018] The following detailed description provides further details on specific implementation methods.

[0019] Example 1 Charging and discharging protection methods for high-voltage energy storage integrated machines based on application scenarios, such as Figure 1 As shown, it includes the following steps: Step 1: Based on the setting parameters of the high-voltage energy storage unit, predict the application scenario range, and form a charging and discharging protection strategy template according to the application scenario range, and store it in the battery management system of the high-voltage energy storage unit. Setting parameters such as power level parameters and energy action time parameters, for example, the application scenarios for power levels ≥100kW include industrial and commercial energy storage, peak shaving and valley filling; the application scenarios for power levels 10-100kW include smoothing wind / solar power output, secondary frequency regulation; the application scenarios for power levels ≤10kW include residential energy storage, solar charging and discharging; the application scenarios for energy action time parameters in the millisecond range include system frequency regulation, voltage compensation; the application scenarios for energy action time parameters in the range of minutes to hours include smoothing wind / solar power output, secondary frequency regulation; the application scenarios for energy action time parameters with a daily or longer cycle include peak shaving and valley filling, load adjustment.

[0020] Examples of charging and discharging protection strategy templates include: For residential peak-valley arbitrage applications, the strategy template distinguishes between peak and off-peak periods and sets charging and discharging thresholds, such as setting peak hours to [18, 19, 20] and off-peak hours to [2, 3, 4], with energy storage capacity threshold set to 0.2 and discharging capacity threshold set to 0.8; For commercial backup power applications, the strategy template prioritizes power supply to critical loads and includes an automatic restart function, such as setting critical loads to ["UPS", "server"], with a backup capacity of 0.5 and an automatic restart function set to True; For photovoltaic-storage microgrid applications, the strategy template features a high self-consumption ratio, supports network connectivity and peak shaving functions, such as setting the self-consumption ratio to 0.8, network connectivity to True, and peak load shaving to True.

[0021] In step 1, the charge and discharge protection strategy template also includes an extreme scenario charge and discharge adjustment strategy. The extreme scenario charge and discharge adjustment strategy includes: under low temperature conditions, such as <0°C, especially <-10°C, preheating the battery pack for a preset duration before charging. The preset duration is set according to the preheating method so that the temperature of the high-voltage energy storage unit can be heated to the condition for safe charging and discharging. During charging and discharging, the charging parameters and discharging parameters are limited to a preset range. The preset range is set according to actual needs, which will not be elaborated here.

[0022] Preheating methods include: Internal heating: Utilizing the internal resistance of the battery cell, low-frequency AC or pulse current is applied through BMS control to generate heat inside the battery cell, resulting in higher efficiency.

[0023] External heating: Controls the PTC heating film or liquid thermal system to heat the battery pack evenly. The preset heating time is slightly longer than that for internal heating.

[0024] Low-temperature charging: Strictly limit the charging rate (C-rate) and cutoff voltage.

[0025] Reduce charging current: Use temperature-current lookup table method or model calculation method. For example, at -10℃, the maximum charging current may be limited to 0.1C or 0.2C (at room temperature it may be 1C).

[0026] Adjust the charging algorithm: change from constant current constant voltage (CC-CV) to multi-stage constant current + reduced cutoff voltage.

[0027] Lowering the cutoff voltage of the CV stage (e.g., from 4.2V to 4.1V) prevents lithium ions from being forcibly intercalated under high voltage, thus preventing lithium plating.

[0028] It is possible to completely eliminate the CV stage and simply use a small constant current to charge to a lower capacity.

[0029] Real-time monitoring: Closely monitor the voltage plateau and dQ / dV (voltage versus capacity) curve of each cell. Any minor voltage anomaly may trigger protection or further derating.

[0030] Low-temperature discharge: derating and power limiting.

[0031] Reduce maximum discharge current: Protect the cell from severe voltage drop and heat buildup caused by high internal resistance.

[0032] SOC display correction: Based on the low-temperature capacity decay model, the displayed remaining power is dynamically adjusted to avoid the phenomenon of "sudden power drop".

[0033] Power Limitation: Inform the PCS or load controller to limit the output power.

[0034] Under high-temperature conditions, i.e., temperatures > 45°C, especially > 60°C, enhanced cooling and charging parameter limits are implemented before and during charging, and the discharge parameters are limited to the set range during discharge.

[0035] Before and during charging: Enhanced cooling and current limiting.

[0036] Initiate forced cooling: Immediately turn on the liquid cooling system or fan to the highest setting to reduce the temperature to the ideal range (e.g., 25-35℃).

[0037] Reduce charging current: Based on the temperature-current relationship table, significantly reduce the charging rate. At extremely high temperatures (e.g., >50°C), charging may be completely prohibited.

[0038] Adjust charging termination conditions: It is possible to reduce the charging cutoff voltage (e.g., from 4.2V to 4.05V) to reduce side reactions and heat generation under high voltage.

[0039] The CV stage may be shortened or eliminated because the battery cell is more likely to reach a "fully charged" state at high temperatures, and the CV stage generates a lot of heat.

[0040] High-temperature discharge: strict power derating and temperature monitoring.

[0041] Reduce the maximum discharge current: to prevent the superposition of ohmic heat and reaction heat, which could lead to uncontrolled temperature rise.

[0042] Dynamic power limiting: Based on real-time temperature and temperature rise rate, calculate the allowable instantaneous power and continuous power, and send them to the PCS or load controller.

[0043] Step 2: Real-time detection of surrounding environmental parameters, including ambient temperature, humidity, and altitude. Based on the environmental parameters, determine the corresponding real-time application scenario, and perform charge and discharge protection of the high-voltage energy storage unit according to the charge and discharge protection strategy corresponding to the real-time application scenario.

[0044] In step 2, the environmental parameters also include environmental images. The temperature change trend in the real-time application scenario is determined based on the environmental images, humidity, and altitude. The temperature change trend includes stable, drastic, and smooth. For example, the indoor shopping mall is stable, while the outdoor environment is judged in conjunction with the season to determine whether it is smooth or drastic.

[0045] Step 3: Dynamically calculate and correct the protection threshold in real time based on environmental parameters. The protection threshold includes the maximum charging current and the dynamic maximum allowable temperature. The corrected protection threshold is used by the battery management system for charge and discharge control.

[0046] In step 3, the theoretical temperature rise limit is first predicted in real time based on the charging time and the amount of charge to be charged. Then, the theoretical temperature rise limit is increased or decreased by the set value in combination with environmental parameters to obtain the predicted temperature rise limit.

[0047] The formula for calculating the maximum charging current is: C_charge_max_dynamic=min(C_chemistry,C_thermal,C_life); Wherein, C_chemistry is the electrochemical limiting current, which is obtained by looking up a table based on the current cell temperature and SOC to obtain the electrochemical limiting current without lithium plating. This value decreases sharply at low temperatures; C_thermal is the thermal limiting current; and C_life is the lifetime limiting current.

[0048] In step 3, a maximum thermal limit current C_thermal is calculated to control the charging process. The calculation formula is: C_thermal=f(Q_max_cooling,T_env_pred,ΔT_to_Tmax), where T_env_pred is the predicted ambient temperature and ΔT_to_Tmax is the temperature difference to reach the dynamic temperature limit.

[0049] The calculation process for the thermal limiting current is as follows: a. Predict the ambient temperature for a future period based on environmental parameters and generate a predicted ambient temperature curve T_env(t). Input the predicted ambient temperature curve T_env(t) for a future period. b. Input the corrected maximum cooling capacity Q_max_cooling of the current cooling system. For example, if the ambient temperature is 25℃ and the upper limit of the safe temperature is 45℃, the calculated result of the maximum cooling capacity is 20W. c. Perform iterative calculations of the thermal model using the current current to predict T_cell_pred(t); d. Reverse solution: Find the maximum constant current value C_thermal such that within the predicted time window (such as the next charging segment), T_cell_pred(t) <= T_max_dynamic - ΔT_margin, where ΔT_margin is the safety margin.

[0050] The formula for calculating the dynamic maximum allowable temperature T_max_dynamic is: T_max_dynamic=min(T_safety,T_life); Among them, T_safety is the hard safety boundary, determined by the cell's chemical system, and is an absolute red line (e.g., 60°C). Under extreme weather warnings, this value can be proactively reduced to increase the safety margin; T_life is the economic boundary of lifespan, dynamically adjusted according to system operating goals. If it is during a peak electricity price period for profitable discharge, T_life can be appropriately increased to obtain greater power; if it is during normal periods, T_life should be decreased to extend lifespan. This value is given by the optimization objectives of the energy management system (EMS).

[0051] Compared with existing technologies, the solution in this embodiment first predicts the scope of the application scenario and then stores the corresponding charge and discharge protection strategy template in the device. By combining scenario prediction and pre-matched storage of charge and discharge strategies, the protection strategy can dynamically change with the application scenario, enabling dynamic adaptation to multiple scenarios and multiple protection strategies. It can pre-set the core objectives for the corresponding scenario, such as prioritizing economy, reliability, and battery life, and can respond with efficient, fast, and accurate protection measures during the charge and discharge process. In the actual control process, the real-time application scenario is judged based on real-time environmental parameters to perform corresponding charge and discharge protection. At the same time, the protection threshold is dynamically calculated and corrected based on temperature prediction, achieving the control operation of charging protection in advance. This realizes the transformation from contact alarm to temperature prediction and active risk avoidance, and can dynamically adjust the protection threshold according to environmental conditions, making the charge and discharge protection control more adaptable to environmental changes and improving the effectiveness of device protection control.

[0052] Example 2 The charging and discharging protection method for high-voltage energy storage integrated machines based on application scenarios differs from Embodiment 1 in that, in step 3, the temperature change type of the application scenario is first determined. This temperature change type includes indoor stable, indoor gradual, outdoor gradual, and outdoor rapid changes. Then, the ambient temperature is predicted based on environmental parameters and the temperature change type. When the temperature change type is indoor stable, a prediction within a preset range is made based on the temperature in the environmental parameters. For example, in summer, indoor environments such as shopping malls are considered indoor stable. If the temperature change in the environmental parameters is within ±3℃, the preset range is a fluctuation of ±3℃ in the ambient temperature. When the temperature change type is indoor gradual... When the temperature is predicted according to the environmental parameters, the ambient temperature is predicted according to a preset trend. For example, in a home setting, the indoor temperature is relatively stable, and the temperature is predicted to gradually increase by 0.5℃ in summer. When the temperature change is relatively stable outdoors, the temperature is predicted according to the seasonal trend, such as a 7℃ increase during the day in summer, and is predicted according to the time period. When the temperature change is rapid outdoors, the temperature is predicted according to the historical degree of change, such as a sudden drop of 10℃ during snowfall in some extreme temperature areas, and is predicted accordingly based on the environmental parameters.

[0053] By defining the types of temperature changes and combining them with the temperature in the application scenario to predict future temperatures, we can make more accurate temperature predictions based on environmental conditions, thereby improving the accuracy of temperature predictions.

[0054] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario, characterized in that, Includes the following steps: Step 1: Based on the setting parameters of the high-voltage energy storage unit, predict the application scenario range, and form a charging and discharging protection strategy template according to the application scenario range, and store it in the battery management system of the high-voltage energy storage unit. Step 2: Real-time detection of surrounding environmental parameters, including ambient temperature, humidity, and altitude; determination of the corresponding real-time application scenario based on the environmental parameters; and implementation of charging and discharging protection for the high-voltage energy storage unit according to the charging and discharging protection strategy corresponding to the real-time application scenario. Step 3: Dynamically calculate and correct the protection threshold in real time based on environmental parameters. The protection threshold includes the maximum charging current and the dynamic maximum allowable temperature. The corrected protection threshold is used by the battery management system for charge and discharge control.

2. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 1, characterized in that: In step 1, the charge and discharge protection strategy template includes an extreme scenario charge and discharge adjustment strategy. The extreme scenario charge and discharge adjustment strategy includes: under low temperature conditions, performing a preheating operation on the battery pack for a preset duration before charging. The preset duration is set according to the preheating method. During charging and discharging, the charging parameters and discharging parameters are limited to a preset range. Under high temperature conditions, enhanced cooling and charging parameter limits are implemented before and during charging, and the discharge parameters are limited to a set range during discharge.

3. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 1, characterized in that: In step 2, the environmental parameters also include environmental images. The temperature change trend in the real-time application scenario is determined based on the environmental images, humidity, and altitude. The temperature change trend includes stable, drastic, and smooth.

4. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 1, characterized in that: In step 3, the theoretical temperature rise limit is first predicted in real time based on the charging time and the amount of charge to be charged. Then, the theoretical temperature rise limit is increased or decreased by a set value based on environmental parameters to obtain the predicted temperature rise limit.

5. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 1, characterized in that: The formula for calculating the maximum charging current is: C_charge_max_dynamic=min(C_chemistry,C_thermal,C_life); Where C_chemistry is the electrochemical limiting current; C_thermal is the thermal limiting current; and C_life is the lifetime limiting current.

6. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 5, characterized in that: In step 3, a maximum thermal limit current C_thermal is calculated to control the charging process. The calculation formula is: C_thermal=f(Q_max_cooling,T_env_pred,ΔT_to_Tmax), where T_env_pred is the predicted ambient temperature and ΔT_to_Tmax is the temperature difference to reach the dynamic temperature limit.

7. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 6, characterized in that: The calculation process for the thermal limiting current is as follows: a. Predict the ambient temperature for a future period based on environmental parameters and generate a predicted ambient temperature curve T_env(t). Input the predicted ambient temperature curve T_env(t) for a future period. b. Input the corrected maximum cooling capacity of the current cooling system, Q_max_cooling; c. Perform iterative calculations of the thermal model using the current current to predict T_cell_pred(t); d. Inverse solution: Find the maximum constant current value C_thermal such that within the predicted time window, T_cell_pred(t) <= T_max_dynamic - ΔT_margin, where ΔT_margin is the safety margin.

8. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 7, characterized in that: The formula for calculating the maximum allowable dynamic temperature T_max_dynamic is as follows: T_max_dynamic=min(T_safety,T_life); Where T_safety is the hard safety boundary; T_life is the economic life boundary.

9. The charging and discharging protection method for a high-voltage energy storage integrated machine based on an application scenario as described in claim 7, characterized in that: The temperature change types include indoor stable, indoor gradual, outdoor gradual, and outdoor rapid. The ambient temperature is predicted by combining environmental parameters and temperature change types. When the temperature change type is indoor stable, the prediction is made within a preset range based on the temperature in the environmental parameters. When the temperature change type is indoor gradual, the predicted ambient temperature is made according to a preset trend based on the temperature in the environmental parameters. When the temperature change type is the outdoor gradual type, the prediction is made based on the seasonal variation trend of the temperature in the environmental parameters; When the temperature change type is the outdoor rapid type, the prediction is made based on the temperature in the environmental parameters according to the historical degree of change.

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