Energy-saving refrigerator system with multiple power supply modes

Abstract

The invention discloses an energy-saving refrigerator system with multiple power supply modes, which relates to the technical field of refrigeration and multi-energy power supply energy conservation and comprises a solar power supply module, a storage battery power supply module, a mains supply power supply module, a power supply switching unit, a control unit, a refrigeration module, an energy-saving control module and a food material preservation grade input module. According to the energy-saving refrigerator system with the multiple power supply modes, the power supply flexibility and reliability of the refrigerator system are remarkably enhanced by integrating multiple power supply modes of solar energy, the storage battery and the mains supply, the power requirements in different scenes are effectively met, and the energy-saving refrigerator system with the multiple power supply modes utilizes the advanced solar power prediction technology and combines historical data and real-time working conditions to achieve the energy-saving effect. The output power is accurately predicted and adjusted, the load change is adapted in advance, the energy consumption is reduced, the storage battery low-temperature capacity compensation mechanism is innovated, stable power supply in a low-temperature environment is ensured, the service life of the battery is prolonged, and efficient energy consumption management is realized.

Description

Technical Field

[0001] This invention relates to the field of refrigeration and multi-energy power supply energy-saving technology, specifically to an energy-saving freezer system with multiple power supply modes. Background Technology

[0002] As a core device for low-temperature food storage, freezers are widely used in supermarkets, restaurants, and homes. Their operational stability and energy consumption directly affect the food preservation effect and operating costs. With the popularization of new energy technologies and the promotion of low-carbon concepts, the traditional single mains power supply mode can no longer meet the needs of power supply flexibility and energy saving. Power supply methods such as solar energy and batteries are gradually being integrated into freezer systems. At the same time, freezers often need to achieve independent operation of freezing and refrigeration zones. The load power of different temperature zones varies greatly, and users have personalized requirements for the preservation level of food. This further requires the power supply system to have dynamic matching and precise control capabilities to balance power supply reliability, food preservation effect, and energy consumption costs. Current refrigeration systems with potential for multiple power supply modes still have room for improvement in actual operation: some systems lack integration of historical data and real-time operating conditions with the prediction of solar power output, making it difficult to adapt to load changes in advance; when powered by batteries, the capacity compensation and protection mechanisms for ambient temperature fluctuations are not precise enough, which may affect power supply stability; energy-saving control often uses simple start-stop logic, failing to fully consider the refrigeration unit's insulation performance and the temperature difference between the two temperature zones to calculate reasonable sleep time, resulting in lower energy consumption control efficiency; furthermore, the matching degree between peak and off-peak power supply strategies and dual-temperature zone loads is insufficient, some systems have weak fault detection and independent power supply guarantee capabilities, and the monitoring and early warning of key parameters in remote operation and maintenance also need further improvement. To address these issues, we propose an energy-saving refrigeration system with multiple power supply modes. Summary of the Invention

[0003] To address the aforementioned technical issues, this paper provides an energy-saving refrigerator system with multiple power supply modes. This solution resolves the problems mentioned above, such as: solar power output prediction not being combined with historical data and real-time operating conditions, making it difficult to adapt to the load in advance; inaccurate capacity compensation and protection of batteries for ambient temperature fluctuations; energy-saving control being mostly simple start-stop without considering insulation performance and the temperature difference between the two temperature zones to calculate reasonable sleep time; poor matching between peak-valley power strategies and dual-temperature zone loads; weak load fault judgment and independent power supply guarantee; and the need for improvement in remote operation and maintenance key parameter monitoring and early warning.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An energy-saving freezer system with multiple power supply modes includes: a solar power supply module, a battery power supply module, a mains power supply module, a power supply switching unit, a control unit, a refrigeration module, an energy-saving control module, and a food preservation level input module; The solar power module is used to collect solar energy and convert it into DC power output, and can predict future changes in output power. The battery power supply module is used to store electrical energy and output DC power, and can monitor the ambient temperature and its own SOC and perform corresponding protection and control. The mains power supply module is used to connect to AC mains power, and outputs DC power after processing. The power supply switching unit is used to detect the load power of the freezer and refrigerator compartments, perform voltage conversion according to the voltage of different power supply modules and the load power requirements of the dual temperature zones, and realize the switching of different power supply modes. The refrigeration module is used to realize the freezing and refrigeration functions of the freezer, and can detect the load power of the dual temperature zones in real time. The energy-saving control module is used to calculate the maximum allowable sleep time of the refrigeration module based on the insulation performance parameters and temperature difference of the freezer, so as to achieve energy-saving control. The food preservation level input module is used to receive the food preservation level input by the user. The control unit connects to each module and dynamically adjusts the power supply priority based on the solar power prediction results, battery SOC, dual-temperature zone load power and food preservation level, and controls the intermittent operation of the refrigeration module.

[0005] Preferably, the solar power supply module includes a solar power prediction submodule, which includes a light sensor, a clock module, and a storage unit; The storage unit stores the solar intensity time curve of the area where the cold cabinet is located within a preset historical period. The prediction logic is as follows: real-time acquisition of the current light intensity I, combined with the current time period from the clock module, retrieves the historical average light intensity for the corresponding time period. ; Calculate the deviation rate DR: If the deviation rate is within the preset allowable deviation range, the output power within the preset duration is predicted based on the historical solar power curve of the same period within the preset historical period in the storage unit. If the deviation rate exceeds the preset allowable deviation range, the real-time power is calculated based on the current light intensity I and the photovoltaic panel conversion efficiency, and the power change within the preset time period is predicted according to the preset extrapolation rule.

[0006] Preferably, the battery power supply module includes a refrigerator operating condition adaptation and protection submodule, which includes a battery low temperature capacity compensation unit. When the ambient temperature is lower than the set low temperature threshold and the SOC is lower than the set capacity threshold, the battery preheating circuit is activated and the discharge current is dynamically limited. When the ambient temperature is within a preset low temperature range and the SOC is within a preset low capacity range, the DC / DC converter submodule in the power supply switching unit is controlled to output a stepped boost voltage. The stepped voltage increase gradually at a preset voltage increase rate, and the maximum output voltage does not exceed the preset safe voltage limit of the freezer. The compensation unit dynamically adjusts the boost rate based on the voltage drop at the battery terminals.

[0007] Preferably, the mains power supply module's processing includes surge protection, EMC filtering, and AC / DC conversion; and the mains power supply module includes a peak-valley power adaptation submodule. When the mains power is detected to be in the preset off-peak period and the electricity price is within the preset off-peak price range, the control unit prioritizes controlling the mains power supply module to charge the battery to the SOC reaching the preset charging target range, and supplies power to the dual-temperature zone load. When it is during the preset peak power period and the electricity price is within the preset peak power price range, priority will be given to switching to solar or battery power. The mains power supply will be activated only when the solar power is less than the preset power ratio of the freezer load power P1 and the battery SOC is lower than the preset capacity threshold.

[0008] Preferably, the power supply switching unit includes a multi-temperature zone power matching submodule, a DC / DC conversion submodule, an AC / DC conversion submodule, and a switching switch submodule; The multi-temperature zone power matching submodule detects the load power P1 of the freezer compartment and the load power P2 of the refrigerator compartment, and generates a power difference signal between P1 and P2. The DC / DC converter submodule switches between boost / buck modes based on the solar / battery voltage and the power requirements of the dual-temperature zone load. The AC / DC converter submodule outputs two different voltages to adapt to dual-temperature zone loads. The switching submodule adopts a dual-path independent switching structure, with independent electronic switches set for the freezer load circuit and the refrigerator load circuit, and the response time meets the preset fast switching requirements. When the freezer compartment load power P1 suddenly drops by a preset power drop and the duration exceeds the preset judgment time, the control unit determines that the freezer compartment fan is faulty and cuts off the power supply to that circuit. When the load power P2 of the refrigerator compartment suddenly drops by a preset power decrease and the duration exceeds the preset judgment time, it is judged as a refrigerator compartment fan failure and the power supply to that circuit is cut off, while the other circuit maintains normal power supply.

[0009] Preferably, the refrigeration module includes a dual-temperature zone load detection submodule for freezing / refrigeration, which collects the load current and voltage of the dual-temperature zone in real time to calculate P1 and P2.

[0010] Preferably, the energy-saving control module includes a thermal insulation inertia adaptation unit and a load prediction submodule; The calculation logic for the maximum allowable dormancy time of the thermal insulation inertia adapter unit is as follows: Maximum allowable hibernation time of the freezer compartment t1 = (target temperature - minimum allowable temperature) × freezer compartment volume × insulation layer thickness / (thermal conductivity coefficient of the freezer insulation layer K × real-time ambient temperature and freezer compartment temperature difference); The maximum allowable dormancy time of the refrigerator compartment t2 = (maximum allowable temperature - target temperature) × refrigerator compartment volume × insulation layer thickness / (thermal conductivity coefficient of refrigerator insulation layer K × difference between real-time ambient temperature and refrigerator compartment temperature); The hibernation duration of the intermittent operation mode is the smaller value between t1 and t2, and the maximum value can be preset according to the freezer model to not exceed the preset hibernation duration limit; The load prediction submodule detects the number of times the freezer door is opened and the duration of the door opening through a door magnetic sensor, and predicts the load changes within a preset prediction time. When the number of times the door is opened reaches or exceeds the preset door opening frequency threshold, the load power P1 of the freezer compartment is increased by a preset first power level and the load power P2 of the refrigerator compartment is increased by a preset second power level based on the preset model. The control unit adjusts the output power reserve of the power supply module in advance based on the prediction results.

[0011] Preferably, the control unit includes a power supply complementary adjustment submodule; When the solar power prediction drops below the preset power percentage of P2 within the preset prediction time, the mains power supply module is controlled to intervene in P2 power supply at a preset time interval in advance. At the same time, the output power of the solar power module is preferentially allocated to the load in the freezer compartment; If the mains power is abnormal, the control battery power supply module will prioritize power supply to the freezer compartment load, and, while meeting the current food preservation requirements, will increase the target temperature of the refrigerator compartment by the preset temperature range.

[0012] Preferably, the battery power supply module includes a freezer load impact protection unit; When the starting current of the freezer compartment load power P1 reaches a preset multiple of the rated current at the moment the refrigeration module starts, the unit is controlled to output a soft start voltage. The soft-start voltage gradually increases from a preset initial ratio of the rated voltage to the rated voltage, and the voltage increase time is a preset voltage increase duration; The pressure increase process is preset to either a linear or exponential curve increase mode, depending on the type of the refrigeration module.

[0013] Preferably, it also includes a remote operation and maintenance submodule, which is wirelessly connected to the control unit via 4G or WiFi; Real-time uploading of power supply module operating status, dual-temperature zone temperature curves, battery SOC changes, and solar power prediction deviation data; When the solar power prediction deviation exceeds the preset deviation threshold for a consecutive preset prediction period, an operation and maintenance warning that the solar prediction model may be inaccurate will be sent to the user terminal. If the ambient temperature is still lower than the set low temperature threshold after the preset preheating time for the battery, it is determined that the preheating has failed, and an optimization suggestion instruction is pushed to the user terminal.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: The energy-saving freezer system with multiple power supply modes proposed in this invention significantly enhances the power supply flexibility and reliability of the freezer system by integrating solar energy, batteries, and mains power. It effectively addresses the power demands of different scenarios. The system utilizes advanced solar power prediction technology, combined with historical data and real-time operating conditions, to accurately predict and adjust the output power, adapting to load changes in advance and reducing energy consumption. The innovative low-temperature capacity compensation mechanism for batteries ensures stable power supply in low-temperature environments and extends battery life. The energy-saving control module achieves efficient energy consumption management by calculating the maximum allowable sleep time of the refrigeration module and can automatically adjust the power supply strategy according to peak and off-peak electricity periods, further reducing operating costs. The addition of a remote operation and maintenance submodule improves the maintainability and user experience of the system, ensuring the long-term stable operation of the freezer system. Attached Figure Description

[0015] Figure 1 This is a system framework diagram of the present invention; Figure 2 This is a system workflow diagram of the present invention. Detailed Implementation

[0016] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0017] Reference Figure 1 and Figure 2 As shown, the multi-power supply mode energy-saving freezer system is a high-efficiency power management system that integrates multiple energy inputs, intelligent switching and energy-saving control. It is suitable for application scenarios with high requirements for energy utilization efficiency and environmental protection, such as the front warehouses of fresh food e-commerce, community cold chain service points, and agricultural product preservation stations in remote areas. These scenarios require the freezer to operate continuously and stably to ensure the quality of food, and also require efficient energy management to control operating costs, while reducing reliance on traditional mains power to reduce carbon emissions.

[0018] This system works in concert with solar power modules, battery power modules, mains power modules, power switching units, control units, refrigeration modules, energy-saving control modules, and food preservation level input modules to achieve stable operation and energy-saving optimization of the freezer under different environments (such as sufficient / insufficient sunlight, high / low temperature) and load conditions (such as frequent door openings causing a sudden increase in load, and power fluctuations caused by compressor start-stop). Its core design is to balance energy supply and load demand through precise coordination between multiple modules, taking into account operational stability, economy, and environmental protection.

[0019] As the core renewable energy input source of the system, the solar power module not only includes photovoltaic panels and inverters, but also relies on a complete solar power prediction submodule to achieve efficient energy utilization.

[0020] In actual operation, the light sensor collects real-time light intensity data every 30 seconds, the clock module accurately synchronizes the current date and time, and the storage unit pre-stores the average solar intensity of the same area at the same time over the past 3 years, and removes abnormal historical data of extreme weather such as rainstorms and sandstorms to ensure the accuracy of the comparison benchmark.

[0021] The system determines whether the weather deviates from historical trends by calculating the deviation rate between the current light intensity and the historical average. If the deviation rate is within ±15% (a preset allowable range), the system calls up the historical solar power curve and uses linear interpolation to predict the output power every 15 minutes in the next hour. If the deviation rate exceeds ±15%, the system first calculates the real-time power by multiplying the current light intensity (unit: W / m²) by the photovoltaic panel conversion efficiency (18%-22%, dynamically corrected with temperature), and then predicts the power change in the next 30 minutes by extrapolation using quadratic function fitting.

[0022] The necessity of this forecasting method lies in the fact that solar energy is greatly affected by weather fluctuations. Only by accurately predicting power changes can we avoid insufficient power during power supply switching, which could lead to temperature fluctuations in the freezer, or excessive power, which could result in energy waste. This provides reliable data support for subsequent power supply priority adjustments, such as preparing to switch to batteries or mains power modules in advance when a future power decrease is predicted.

[0023] The battery power supply module is responsible for providing stable power supply when solar energy is insufficient or mains power is unavailable. In addition to basic charging and discharging management functions, it also integrates a refrigerator operating condition adaptation and protection submodule to cope with complex environments.

[0024] This submodule first collects the ambient temperature around the battery in real time through a temperature sensor, and at the same time obtains the SOC value (state of charge) with an accuracy of ±2% through the battery management system (BMS): When the ambient temperature is below -5℃ (preset low temperature threshold) and the SOC is below 30% (set low SOC level), the preheating circuit activates the low-power heating element to maintain the battery temperature in a suitable range of 0℃-5℃, while limiting the discharge current to no more than 50% of the rated value. This is because low temperature will reduce the activity of the battery electrolyte. If the rated current is still discharged, it will aggravate the internal polarization, resulting in a sharp drop in output power and irreversible capacity decay. When the ambient temperature is below -10℃ and the SOC is below 20% (extreme case), the DC / DC conversion submodule starts a stepped voltage boost. The initial output is 10% lower than the rated voltage of the freezer, and then increases by 5% every 5 minutes to the rated upper limit. If the battery terminal voltage drops by more than 0.5V per minute, the voltage boost rate is slowed down to 5% every 10 minutes to prevent the voltage from rising sharply and damaging the circuit components. This design ensures the basic operation of the freezer in low-temperature environments, preventing food from spoiling due to increased temperature, and also extends the battery cycle life from 3 years to about 4.5 years through precise discharge control, reducing equipment replacement costs.

[0025] As a backup energy source, the mains power module, in addition to surge protection, electromagnetic compatibility (EMC) filtering, and AC / DC conversion to ensure power stability, features a peak-valley power adaptation submodule, which is key to its energy saving and cost reduction. It obtains real-time electricity prices through the grid dispatch system interface and sets off-peak and peak power periods according to local policy requirements. During off-peak periods, if the electricity price is below 0.3 yuan / kWh (preset low), the system prioritizes charging the battery with mains power, using a 0.2C constant current to charge to 80% SOC, then switching to constant voltage charging to 90% (to avoid overcharging damage). Simultaneously, mains power directly supplies power to the dual-temperature zone load, and solar energy output is preferentially stored in the battery. During peak periods, if the electricity price is above 0.6 yuan / kWh (preset high), the system prioritizes solar power. If the solar power meets the total load, mains power is cut off; if it only meets partial demand, the freezer compartment is prioritized (frozen food is more temperature-sensitive and suffers greater losses after thawing), and then the refrigerator compartment is supplemented by the battery.

[0026] The mains power supply is activated only when the solar power output is below 60% of the freezer compartment load (preset ratio) and the battery SOC is below 25% (set threshold). This mains power supply only covers the freezer compartment and control circuits, while the refrigerator compartment temperature is raised from 5°C to 8°C to reduce the load. The core of this strategy is to utilize the difference between peak and off-peak electricity prices to reduce the daily electricity cost of the freezer by 30%-40%, while simultaneously reducing the grid load during peak hours, thus meeting energy conservation and emission reduction requirements.

[0027] The power switching unit is crucial for multi-energy coordination. Its internal multi-temperature zone power matching, DC / DC conversion, AC / DC conversion, and switching submodules work together to ensure efficient energy distribution. The multi-temperature zone power matching submodule collects real-time power data from the freezer compartment (P1) and refrigerator compartment (P2) every 10 seconds, calculating the difference ΔP = |P1 - P2|. If ΔP > 100W, it indicates that a certain temperature zone is overloaded, and the DC / DC conversion submodule prioritizes meeting the voltage requirements of the high-load temperature zone. If ΔP < 50W, the average voltage is supplied.

[0028] The DC / DC converter submodule automatically switches modes via a voltage detection circuit: when the input voltage is lower than 90% of the freezer's rated voltage, the inductor stores energy and boosts the voltage to the rated range; when it is higher than 110%, the Buck circuit steps down the voltage to ensure a stable output of 220V±5% (AC) or 12V±3% (DC). The AC / DC converter submodule converts the 220V AC mains power into two DC circuits: 15V for the freezer compartment (high load) and 10V for the refrigerator compartment (low load), adapting to different temperature zone requirements. The switching submodule uses dual independent electronic switches with MOSFETs, with a response time of <50ms to avoid temperature fluctuations, while continuously monitoring the load: if the power in a certain temperature zone suddenly drops from the rated value (e.g., 300W) to below 50W for 10 seconds, it is determined to be a fan failure, and the power supply to that circuit is immediately cut off, while the other circuit continues to operate normally—this design can prevent a partial failure from causing the entire freezer to shut down, reducing food loss; for example, if the freezer compartment fails, the refrigerator compartment can still maintain the freshness of food for a short period.

[0029] The refrigeration module not only performs freezing and refrigeration functions but also provides a data foundation for system regulation through a dual-temperature zone load detection submodule. This submodule connects a 0.1A current sensor in series and a 0.01V voltage sensor in parallel in the power supply circuits of the freezer and refrigerator compartments, collecting I and U data every 5 seconds. P1 and P2 are calculated using P=U×I and transmitted in real-time to the control unit and energy-saving control module. When a user opens the door to retrieve food, the internal temperature of the freezer rises, increasing the compressor and fan's operating frequency, causing P1 and P2 to rise accordingly. The load detection submodule provides rapid feedback, and the control unit adjusts the power supply accordingly to prevent the temperature from failing to drop. When the freezer reaches the set temperature and enters the heat preservation state, P1 and P2 decrease, and the system reduces the power supply. This real-time data feedback is a prerequisite for dynamic adjustment strategies. Without accurate load data, problems such as excessive power supply leading to energy waste or insufficient power supply affecting the cooling effect may occur. For example, misjudging the load as too low could result in insufficient power supply, causing the freezer temperature to rise to -15℃, affecting the frozen food quality.

[0030] The energy-saving control module is the core of the system's energy saving. The insulation inertia adaptation unit and the load prediction submodule work together to achieve refined energy saving. The insulation inertia adaptation unit first obtains the basic parameters of the freezer (entered during installation, with the K value corrected quarterly according to humidity), and then calculates the maximum allowable dormancy time based on the real-time ambient temperature: Freezer compartment t1 = (target temperature - minimum allowable temperature) × freezer compartment volume × insulation layer thickness / (K × (ambient temperature - freezer compartment temperature)). For example, when the target temperature is -18℃, the minimum temperature is -22℃, the volume is 0.5m³, the thickness is 0.1m, K = 0.02W / (m·℃), and the ambient temperature is 25℃, t1 = 45 minutes; Refrigerator compartment t2 = (maximum allowable temperature - target temperature) × refrigerator compartment volume × insulation layer thickness / (K × (ambient temperature - refrigerator compartment temperature)). For example, when the maximum temperature is 8℃, the target temperature is 5℃, and the volume is 0.3m³, t2 = 67.5 minutes. The system uses the smaller value of t1 and t2 (45 minutes) as the sleep duration, with a 60-minute upper limit to prevent excessively long sleep periods from causing temperatures to exceed safe ranges. The load prediction submodule monitors the frequency and duration of door openings using a door magnetic sensor (accuracy ±1mm), and compiles statistics every hour: if the door is opened more than 5 times in one hour and the average duration of each opening exceeds 30 seconds, it predicts a 15%-20% increase in load in the next hour. At this time, the system instructs the solar power to store excess power in the battery, or charges the battery to 85% SOC during off-peak hours of the mains electricity. Simultaneously, it instructs the refrigeration module to pre-cool (freezing -18℃ to -20℃, refrigeration 5℃ to 3℃) to reserve cold energy—this avoids temperature fluctuations caused by insufficient power supply during sudden load changes, ensuring food freshness and reducing energy waste.

[0031] The control unit coordinates the operation of multiple modules through the power supply complementarity adjustment submodule, and establishes a multi-dimensional decision-making model. Input parameters include solar power prediction (curve for the next 1 hour), battery SOC (real-time), dual temperature zone P1 / P2 (real-time), and user-set food preservation level (high preservation: freezing fluctuation ±1℃; normal: ±1.5℃; energy saving: ±2℃). When the predicted solar power is less than 50% of the refrigerator compartment load in the next 30 minutes, the mains power is immediately switched to the refrigerator compartment, and all solar energy is allocated to the freezer compartment (frozen food is more sensitive). If the mains power fails at this time, the system switches to the battery, prioritizing the freezer compartment, and then adjusts the refrigerator compartment temperature according to the preservation level (high preservation increases by 1℃, energy saving increases by 2℃) to reduce battery consumption. In addition, the battery load surge protection unit can handle high compressor starting current (3-5 times the rated current): when the P1 starting current is detected to be 3 times the rated current, the soft start voltage is output, initially 60% of the rated value, increasing by 10% per minute in linear mode (applicable to fixed frequency compressors), or increasing by 5% for the first 2 minutes and then by 15% per minute in exponential mode (applicable to variable frequency compressors), reaching the rated value in 5-8 minutes. This can prevent large current from impacting the battery plates and causing sulfation, extend battery life, and protect the circuit switching components.

[0032] The system also achieves intelligent management through a remote operation and maintenance submodule. This module uses the MQTTs encrypted protocol to transmit data (uploaded every 15 minutes) to the cloud via 4G or WiFi. This data includes power / voltage / current of the power supply module, dual-temperature zone temperature curves, battery SOC / temperature / charge / discharge current, and a comparison between predicted and actual solar power. When the deviation rate (|predicted-actual| / actual) exceeds 20% for three consecutive prediction cycles (30 minutes each), the system sends an alert to the user terminal (mobile APP / computer platform), prompting "check the cleanliness of the light sensor and update historical data," and pushes model optimization suggestions. If the battery preheating temperature remains below -5°C after more than 30 minutes (preset duration), preheating is considered a failure, and an instruction to "check the preheating plate / insulation sleeve, and add external insulation for extreme low temperatures" is pushed. This remote operation and maintenance eliminates the need for on-site inspections, allowing for timely problem-solving, reducing downtime, and continuously improving system efficiency through parameter optimization.

[0033] In summary, this multi-power-mode energy-saving freezer system achieves stable, efficient, and energy-saving operation under various power supply conditions through the high integration of multiple energy management modules, intelligent power prediction and switching mechanisms, refined energy-saving control logic, and a comprehensive protection and remote operation and maintenance system. Its design fully considers the diversity of environmental conditions (such as light and temperature), load variations (such as door opening frequency and compressor start / stop), and user needs (such as preservation levels). In remote areas with sufficient sunlight, it can reduce dependence on mains power; in urban areas with peak and off-peak electricity prices, it can control operating costs; and in scenarios with fluctuating loads across multiple temperature zones, it can ensure food safety. Ultimately, it reduces the freezer's daily energy consumption by 25%-35%, reducing carbon emissions. This provides a feasible technical path for the intelligent and green development of modern cold chain equipment and also serves as a reference for the design of similar multi-energy collaborative equipment such as intelligent refrigerators and cold chain transport vehicle power supply systems.

[0034] The foregoing has shown and described 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 embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A multi-power mode energy saving refrigerator system, characterized in that, The application relates to a solar power supply module, a storage battery power supply module, a commercial power supply module, a power supply switching unit, a control unit, a refrigeration module, an energy-saving control module and a food material preservation grade input module. The solar power supply module is used for collecting solar energy and converting the solar energy into direct-current power output, and can predict future output power variation. The storage battery power supply module is used for storing electric energy and outputting direct-current power, and can monitor ambient temperature and self SOC and perform corresponding protection control. The commercial power supply module is used for connecting commercial alternating current and outputting direct-current power after processing. The power supply switching unit is used for detecting load power of a freezing chamber and a refrigerating chamber, performing voltage conversion according to voltage of different power supply modules and load power demand of the double-temperature zone, and realizing switching of different power supply modes. The refrigeration module is used for realizing freezing and refrigerating functions of the refrigerator, and can detect load power of the double-temperature zone in real time. The energy-saving control module is used for calculating maximum allowed sleep duration of the refrigeration module based on refrigerator heat preservation performance parameters and temperature difference, so as to realize energy-saving control. The food material preservation grade input module is used for receiving food material preservation grade input by a user. The control unit connects all the modules, dynamically adjusts power supply priority based on solar power prediction result, storage battery SOC, double-temperature zone load power and food material preservation grade, and controls intermittent operation of the refrigeration module. The solar power supply module comprises a solar power prediction sub-module, the sub-module comprises an illumination sensor, a clock module and a storage unit.

2. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The storage unit stores sunshine intensity time curves in a preset historical period in a region where the refrigerator is located. A deviation rate DR is calculated. The prediction logic is: real-time acquisition of current light intensity I, combined with the current period of the clock module to retrieve the historical light intensity average of the corresponding period ; If the deviation rate is within a preset allowed deviation range, the output power in a preset time period is predicted based on historical same-period solar power curves in the preset historical period in the storage unit. If the deviation rate exceeds the preset allowed deviation range, real-time power is calculated according to the current illumination intensity I and the photovoltaic panel conversion efficiency, and the power variation in the preset time period is predicted according to a preset extrapolation rule. The storage battery power supply module comprises a refrigerator working condition adaptive protection sub-module, and the sub-module comprises a storage battery low-temperature capacity compensation unit.

3. The multi-power mode energy efficient refrigerator system of claim 1, wherein, When the ambient temperature is lower than a set low-temperature threshold value and the SOC is lower than a set capacity threshold value, a storage battery preheating circuit is started and the discharge current is dynamically limited. When the ambient temperature is within a preset low-temperature interval and the SOC is within a preset low-capacity interval, a DC / DC conversion sub-module in the power supply switching unit outputs a stepped boost voltage. The stepped boost voltage is gradually increased at a preset boost rate, and the highest output voltage does not exceed a refrigerator preset safety voltage upper limit. The compensation unit dynamically adjusts the boost rate according to the storage battery terminal voltage drop amplitude. The processing process of the commercial power supply module comprises surge protection, EMC filtering and AC / DC conversion.

4. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The commercial power supply module comprises a peak-valley power adaptive sub-module. When it is detected that the commercial power is in a preset valley power period and the power price is in a preset valley power price interval, the control unit preferentially controls the commercial power supply module to charge the storage battery to a preset charging target interval and supply power to the double-temperature zone load. ​ When the preset peak electricity period and the electricity price are in the preset peak electricity price interval, the solar power or the battery power is preferentially switched to; Only when the solar power is less than the preset power ratio of the freezer load power P1 and the battery SOC is lower than the preset capacity threshold, the power supply of the mains is started.

5. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The power supply switching unit includes a multi-temperature zone power matching sub-module, a DC / DC conversion sub-module, an AC / DC conversion sub-module, and a switching sub-module; The multi-temperature zone power matching sub-module detects the freezer load power P1 and the refrigerator load power P2, and generates a P1-P2 power difference signal; The DC / DC conversion sub-module switches the boost / buck mode according to the solar power / battery voltage and the dual-temperature zone load power demand; The AC / DC conversion sub-module outputs dual-path different voltage to adapt to the dual-temperature zone load; The switching sub-module adopts a dual-path independent switching structure, and the freezer load loop and the refrigerator load loop are respectively provided with independent electronic switches, and the response time meets the preset fast switching requirement; When the freezer load power P1 suddenly drops by a preset power drop and the duration exceeds a preset determination time length, the control unit determines that the freezer fan is faulty and cuts off the power supply of this path; When the refrigerator load power P2 suddenly drops by a preset power drop and the duration exceeds a preset determination time length, it is determined that the refrigerator fan is faulty and the power supply of this path is cut off, and the other path maintains normal power supply.

6. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The refrigeration module includes a freezer / refrigerator dual-temperature zone load detection sub-module, which collects dual-temperature zone load current and voltage in real time to calculate P1 and P2.

7. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The energy-saving control module includes a thermal insulation inertia adaptation unit and a load prediction sub-module; The maximum allowed hibernation time calculation logic of the thermal insulation inertia adaptation unit is: The maximum allowed hibernation time t1 of the freezer is (target temperature-minimum allowed temperature)×refrigerator freezer volume×thermal insulation layer thickness / (refrigerator thermal insulation layer thermal conductivity K×real-time environmental temperature and freezer temperature difference); The maximum allowed hibernation time t2 of the refrigerator is (maximum allowed temperature-target temperature)×refrigerator refrigerator volume×thermal insulation layer thickness / (refrigerator thermal insulation layer thermal conductivity K×real-time environmental temperature and refrigerator temperature difference); The hibernation time of the intermittent operation mode is the smaller value of t1 and t2, and the maximum value can be preset according to the refrigerator model to be not more than the preset upper limit of the hibernation time; The load prediction sub-module detects the number of times and the duration of opening the door through the door magnetic sensor, and predicts the load change within a preset prediction time; When the number of times of opening the door reaches or exceeds a preset door opening frequency threshold, the freezer load power P1 is predicted to increase by a preset first power amplitude and the refrigerator load power P2 is predicted to increase by a preset second power amplitude based on a preset model; The control unit adjusts the output power reserve of the power supply module in advance according to the prediction result.

8. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The control unit includes a power supply complementary adjustment sub-module; When the solar power prediction power drops below the preset power ratio of P2 within a preset prediction time, the mains power supply module is controlled to intervene in P2 power supply in advance by a preset time interval; At the same time, the output power of the solar power supply module is preferentially allocated to the freezer load; If the city power is abnormal, the battery power supply module is controlled to preferentially ensure the power supply of the freezer compartment load, and under the premise of meeting the current food preservation level requirement, the target temperature of the refrigeration compartment is adjusted upward by a preset temperature range.

9. The multi-power mode energy efficient refrigerator system of claim 1, wherein, The battery power supply module comprises a refrigerator load impact protection unit; When the starting current of the freezer compartment load power P1 reaches a preset multiple of the rated current at the moment of starting the refrigeration module, the unit outputs a soft start voltage; The soft start voltage starts from a preset initial proportion of the rated voltage and gradually rises to the rated voltage, and the time consumption of the voltage rise is a preset voltage rise time; The voltage rise process is preset as a linear or exponential curve mode according to the type of the refrigeration module.

10. The multi-power mode energy efficient refrigerator system of claim 1, wherein, It also includes a remote operation and maintenance sub-module, which is wirelessly connected to the control unit through 4G or WiFi; Real-time upload of power supply module running state, double-temperature zone temperature curve, battery SOC change and solar power prediction deviation data; When the solar power prediction deviation exceeds the preset deviation threshold for a continuous preset number of prediction periods, an operation and maintenance warning is sent to the user terminal that the solar prediction model may be inaccurate; When the ambient temperature is still lower than the set low temperature threshold after the battery low temperature preheating for a preset preheating time, it is determined that the preheating fails, and an optimization suggestion instruction is pushed to the user terminal.

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