High and cold region aerobic composting system and method based on light storage and energy supply integration

Abstract

The invention relates to the field of composting management systems, and particularly discloses an alpine region aerobic composting system and method based on light storage and energy supply integration, the system comprises a composting barrel main body, the composting barrel main body is internally provided with a heating unit, a temperature sensor and a ventilation pipeline, and the bottom of the composting barrel main body is provided with a discharge port; the photovoltaic power generation module is used for converting solar energy into light energy; the inverter module is electrically connected with the photovoltaic power generation module, has an MPPT (maximum power point tracking) function and is used for converting direct-current electric energy input by the photovoltaic power generation module into first current or second current, and the first current is used for directly supplying power to the heating unit; the sodium ion battery energy storage module is mounted on the side surface of the composting barrel main body and is used for receiving the second current as charging current or outputting third current to supply power to the heating unit. By adopting the technical scheme provided by the invention, the aerobic composting maturity of the alpine region can be improved, and the operation cost is relatively low.

Description

Technical Field

[0001] The present invention relates to the field of compost management systems, and in particular to an aerobic composting system and method for high-altitude cold regions based on integrated photovoltaic storage and energy supply. Background Art

[0002] In rural domestic waste disposal scenarios in high-altitude, cold regions, the contradiction between low temperatures and outdated treatment facilities has long existed. Due to geographical and climatic conditions, the average winter temperature in these areas often falls below -10°C, with extreme lows reaching -40°C. This has led to significant technical bottlenecks in traditional aerobic composting. Aerobic fermentation relies on microbial activity, but low temperatures significantly reduce the metabolic rate of microorganisms, making it difficult to maintain the compost temperature within the optimal reaction range of 55-65°C. This directly results in the composting cycle being extended to over 50 days, and the degree of maturity reaching only around 60%, far below the quality requirements for organic fertilizers in agricultural production.

[0003] Existing household composting equipment suffers from a widespread energy shortage. Traditional composting vats are often heated by mains electricity, consuming an average of 1.44 kWh per day. Based on residential electricity prices, annual operating costs exceed 500 yuan, with energy costs accounting for over 35% of the equipment's operating and maintenance costs. Furthermore, remote villages often face issues with insufficient grid coverage or significant voltage fluctuations, leading to unstable heating systems. When ambient temperatures fall below 0°C, the compost temperature frequently drops below the critical threshold for microbial activity, repeatedly interrupting the fermentation process. This not only affects composting efficiency but also creates an anaerobic odor, reducing farmer acceptance.

[0004] Therefore, there is an urgent need for an aerobic composting system and method for alpine regions based on integrated photovoltaic storage and energy supply, which can improve the maturity of aerobic composting in alpine regions and has low operating costs. Summary of the Invention

[0005] The present invention provides an aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply, which can improve the maturity of aerobic composting in high-altitude cold regions and has low operating costs.

[0006] In order to solve the above technical problems, this application provides the following technical solutions: The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply includes: A compost bucket body, wherein a heating unit, a temperature sensor and a ventilation duct are provided inside the compost bucket body, and a discharge port is provided at the bottom of the compost bucket body; A photovoltaic power generation module, which is used to convert solar energy into light energy; an inverter module, the inverter module being electrically connected to the photovoltaic power generation module and having an MPPT (maximum power point tracking) function, for converting the DC power input by the photovoltaic power generation module into a first current or a second current, wherein the first current is used to directly power the heating unit; A sodium ion battery energy storage module is installed on the side of the compost bucket body and is used to receive the second current as a charging current or output a third current to power the heating unit; The intelligent control module is used to obtain the photovoltaic power and battery energy storage status, and obtain the stack temperature data through the temperature sensor. It executes the control strategy based on the fuzzy PID algorithm. When the light intensity is not less than the preset value, the photovoltaic power is used first to charge the battery. When the battery power is lower than the preset value, it automatically switches to the mains power to charge the sodium-ion battery energy storage module. The heating unit is controlled to start or stop according to the stack temperature data.

[0007] The basic principles and beneficial effects of this solution are as follows: Through the coordinated operation of various modules, this invention creates stable, high-temperature, aerobic fermentation conditions for composting in cold environments. The photovoltaic power generation module converts solar energy into DC power. After conversion using the inverter module's MPPT tracking technology, the primary current is prioritized and directly powers the heating unit within the barrel. The heating unit maintains the compost temperature, enhancing aerobic microbial activity and accelerating the decomposition of organic matter.

[0008] The inverter module stores excess solar energy as a secondary current in a sodium-ion battery storage module mounted on the side of the compost bin. When needed, it outputs a tertiary current to continue powering the heating unit. The compost bin's insulation structure, combined with the temperature sensor in the intelligent control module, monitors the compost temperature in real time. Heating activates when it falls below a set point and shuts off when it exceeds, keeping temperature fluctuations within a preset range. Meanwhile, ventilation ducts continuously supply oxygen to the compost, ensuring continuous aerobic fermentation. This ultimately increases compost maturity from 60% with traditional technology to over 95%, shortening the fermentation cycle.

[0009] Low-cost operation is achieved through an energy management model that prioritizes photovoltaics and intelligent energy storage. On sunny days, the photovoltaic power generation module can fully meet the heating unit's 1.44 kWh / day electricity demand. On cloudy days, the sodium-ion battery energy storage module can still provide power, automatically switching to the mains only when the battery charge drops below 20%. The sodium-ion batteries are installed on the side of the barrel, allowing residual heat to insulate the sodium-ion battery energy storage module, enhancing its efficiency.

[0010] In summary, the present invention achieves the purpose of improving the maturity of aerobic composting in high-altitude cold areas with low operating costs.

[0011] Furthermore, the heating unit inside the compost bin body is a medium-temperature self-controlling electric heating tape. The electric heating tape is spirally wound around the inner wall of the compost bin body with a winding spacing of 10-15 cm, a total length of 5.8 meters, a rated power of 60W, and an operating voltage of 24V safety voltage. The maximum maintenance temperature of the electric heating tape is 65°C, and the surface temperature is controlled at 70±5°C. When the compost body temperature exceeds 70°C, the power is automatically cut off through the linkage control of the temperature sensor and the intelligent control module, and heating is automatically started when it is lower than 65°C.

[0012] Furthermore, the temperature sensor is a high-precision Pt100 thermal resistance sensor, which is distributed in three layers inside the compost bucket body, and is respectively set at 1 / 3, 1 / 2 and 2 / 3 of the pile height. 2-3 sensors are evenly arranged on each layer to monitor the temperature data at different depths of the pile in real time and transmit it to the intelligent control module.

[0013] Furthermore, the ventilation duct is made of PVC and is laid in a grid pattern on the bottom of the compost barrel body. The duct diameter is 10-15 mm, and ventilation holes with a diameter of 2-3 mm are opened on the surface, with a hole spacing of 20-30 mm. The ventilation duct is connected to an external blower through a duct joint; the blower is a variable frequency centrifugal fan, and the intelligent control module is controlled and connected to the variable frequency centrifugal fan. The variable frequency centrifugal fan uniformly delivers air to the pile through the bottom ventilation holes according to the control instructions of the intelligent control module, thereby meeting the oxygen needs of aerobic microorganisms and reducing the humidity of the pile through air circulation.

[0014] Furthermore, the discharge port at the bottom of the compost barrel body is designed with an inclination angle of 15°-20°, the discharge port width is 30-40 cm, and an electric gate is installed inside, and the electric gate is electrically connected to the intelligent control module.

[0015] Furthermore, the intelligent control module is also used to output a PWM pulse signal to control the operation of the MPPT module of the inverter when the light intensity sensor detects a value ≥ 200W / ㎡, thereby locking the maximum power point voltage of the photovoltaic array within the range of 24V±0.5V, and at the same time sending a charging instruction to the BMS of the sodium-ion battery energy storage module. The charging current is charged at a constant current of 0.5C until the battery SOC reaches 90%, and then switched to constant voltage charging; when the SOC of the sodium-ion battery energy storage module is less than 20%, the intelligent control module controls the mains charging circuit by closing the relay on the mains power supply circuit, and at the same time reduces the heating power of the electric heating tape to 60% of the rated power.

[0016] Ensure energy-saving operation of non-critical loads and avoid heating interruption caused by battery depletion.

[0017] Furthermore, the intelligent control module is also used to automatically calculate the heating power of the electric heating tape according to the temperature deviation ΔT when the three-layer three-dimensionally distributed Pt100 temperature sensors detect that the temperature of any layer is less than 65°C. ΔT is the difference between the actual measured temperature and 65°C. The fuzzy PID algorithm is used to output the control signal to adjust the heating power dynamically within the range of 20%-100%. When the temperature is ≥70°C, the power supply of the electric heating tape is immediately cut off. At the same time, the intelligent control module starts the blower of the ventilation duct according to the temperature gradient data when the temperature difference between the top and bottom layers is greater than 5°C.

[0018] Solve the problem of local temperature unevenness in the pile and ensure that the uniformity error of the temperature field of the pile is ≤±2℃.

[0019] Furthermore, the intelligent control module has a built-in temperature change rate prediction model, which can predict the temperature trend of the stack in advance through differential calculation and state space modeling of historical temperature data, including the following contents: The five-point central difference method is used to calculate the real-time temperature change rate. The formula is:

[0020] in For the moment The stack temperature detection value, is the sampling interval, is the temperature change rate; Construct a state equation containing temperature trend terms and disturbance terms:

[0021] The state vector , is the temperature acceleration compensation term, and are process noise and observation noise, respectively, both of which obey normal distribution and , iteratively update the state estimate through Kalman filtering; The intelligent control module is also used to start the electric heating tape in advance and increase the heating power to the rated power when the prediction model shows that the pile temperature will drop below 65°C within 1 hour. At the same time, it starts the blower for ventilation to improve the temperature response speed.

[0022] Furthermore, the intelligent control module is also used to build a multi-parameter correlation abnormality diagnosis model, which realizes real-time identification of equipment abnormalities through mutual verification of the heating unit power consumption-temperature response curve, the blower air volume-oxygen concentration gradient and sensor data, specifically including: Establish the power consumption-temperature transfer function model:

[0023] in is the steady-state gain, under normal working conditions , It is the lag time. Normally it is 15-20 minutes. The time constant is 40-50 minutes normally. When the measured transfer function parameter deviates from the normal value by ±20%, it is determined that the electric heating cable is aging or has poor contact. When the heating efficiency drops, the alarm is triggered; The oxygen concentration gradient coefficient of variation method is used:

[0024] in is the standard deviation of oxygen concentration at the corresponding positions of the three-layer temperature sensors, is the average value, under normal working conditions ,when If the condition persists for more than 10 minutes, it is determined that the blower impeller is dusty or the pipe is clogged; Construct a three-layer sensor data mutual verification matrix:

[0025] Calculate the residual vector ,when hour, is the residual standard deviation, normally 0.5°C, which is used to determine whether the corresponding sensor is drifting or disconnected. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The logical block diagram of an embodiment of an aerobic composting system in high-altitude cold regions based on integrated photovoltaic storage and energy supply. DETAILED DESCRIPTION

[0027] The following is further described in detail through specific implementation methods: Aerobic composting system in high-altitude cold regions based on integrated photovoltaic storage and energy supply (such as Figure 1 shown), including: A compost bucket body, wherein a heating unit, a temperature sensor and a ventilation duct are provided inside the compost bucket body, and a discharge port is provided at the bottom of the compost bucket body; A photovoltaic power generation module, which is used to convert solar energy into light energy; an inverter module, the inverter module being electrically connected to the photovoltaic power generation module and having an MPPT (maximum power point tracking) function, for converting the DC power input by the photovoltaic power generation module into a first current or a second current, wherein the first current is used to directly power the heating unit; A sodium ion battery energy storage module is installed on the side of the compost bucket body and is used to receive the second current as a charging current or output a third current to power the heating unit; The intelligent control module is used to obtain the photovoltaic power and battery energy storage status, and obtain the stack temperature data through the temperature sensor. It executes the control strategy based on the fuzzy PID algorithm. When the light intensity is not less than the preset value, the photovoltaic power is used first to charge the battery. When the battery power is lower than the preset value, it automatically switches to the mains power to charge the sodium-ion battery energy storage module. The heating unit is controlled to start or stop according to the stack temperature data.

[0028] The heating unit inside the compost bin body is a medium-temperature self-controlling electric heating tape. The electric heating tape is spirally wound around the inner wall of the compost bin body with a winding spacing of 10-15 cm. The total length is 5.8 meters, the rated power is 60W, and the operating voltage is 24V safety voltage. The maximum maintenance temperature of the electric heating tape is 65°C, and the surface temperature is controlled at 70±5°C. When the compost body temperature exceeds 70°C, the power is automatically cut off through the linkage control of the temperature sensor. When it is lower than 65°C, heating is automatically started, thereby solving the problem of maintaining the compost body temperature in cold areas and low temperature environments, and ensuring the appropriate temperature range required for microbial activity.

[0029] The temperature sensor is a high-precision Pt100 thermistor sensor, which is distributed in three layers inside the compost bin, located at 1 / 3, 1 / 2 and 2 / 3 of the pile height respectively. 2-3 sensors are evenly arranged on each layer to monitor the temperature data at different depths of the pile in real time and transmit it to the intelligent control system, avoiding the temperature monitoring blind spots caused by traditional single-point temperature measurement, solving the problem of local overheating or insufficient heating of the pile, and achieving precise control of the temperature field.

[0030] The ventilation duct is made of PVC and is laid in a grid pattern at the bottom of the compost barrel. The diameter of the duct is 10-15mm, and ventilation holes with a diameter of 2-3mm are opened on the surface, with a hole spacing of 20-30mm. The ventilation duct is connected to an external blower through a duct joint; the blower is a variable frequency centrifugal fan, which can adjust the air volume according to the instructions of the intelligent control system, and evenly transport air to the pile through the bottom ventilation holes to meet the oxygen needs of aerobic microorganisms (oxygen concentration is maintained at ≥18%). At the same time, the humidity of the pile is adjusted through air circulation (controlled at 50%-60%) to avoid odor caused by anaerobic fermentation and solve the problem of insufficient fermentation caused by low ventilation efficiency in cold areas.

[0031] The discharge port at the bottom of the compost bin is designed with an inclination angle of 15°-20° and a width of 30-40cm. An electric gate is installed inside. The gate is electrically connected to the intelligent control system and can be automatically opened / closed by remote control or timing control. The inclined structure combined with the electric gate design facilitates the automatic discharge of materials by gravity after composting is completed, solving the problem of material residue at the traditional vertical discharge port. It can also maintain a sealed state during the composting process, reduce heat loss, and ensure stable temperature of the compost.

[0032] The intelligent control module uses an industrial-grade PLC controller as its core processing unit. The PLC controller model uses the Siemens S7-200 SMART series, which has 16 digital input / output interfaces and 8 analog input interfaces. It can collect real-time output voltage / current data of the photovoltaic power generation module, the remaining capacity (SOC) of the sodium-ion battery energy storage module, the Pt100 resistance signal of the stack temperature sensor, and the voltage signal of the ambient light intensity sensor; the intelligent control module is connected to various sensors and actuators through the RS485 communication bus, and the communication protocol adopts Modbus RTU to ensure that the data transmission delay is ≤50ms, solving the communication jamming problem during real-time acquisition of multiple parameters.

[0033] The fuzzy PID algorithm control strategy built into the intelligent control module specifically includes the following: when the light intensity sensor detects a value ≥ 200W / ㎡, it outputs a PWM pulse signal to control the inverter's MPPT module to operate, locking the maximum power point voltage of the photovoltaic array within the range of 24V±0.5V. At the same time, it sends a charging instruction to the BMS of the sodium-ion battery energy storage module. The charging current is charged at a constant current of 0.5C until the battery SOC reaches 90%, and then switches to constant voltage charging. This achieves priority utilization of light energy and efficient charging management of the energy storage battery, solving the energy waste problem of traditional photovoltaic systems; when the SOC of the sodium-ion battery energy storage module is less than 20%, the intelligent control module outputs a relay signal to connect the AC charging circuit and simultaneously reduces the heating power of the electric heating tape to 60% of the rated power, ensuring energy-saving operation of non-critical loads and avoiding heating interruptions due to battery depletion.

[0034] The stack temperature control logic is as follows: when the three-layer three-dimensionally distributed Pt100 temperature sensors detect that the temperature of any layer is less than 65°C, the intelligent control module automatically calculates the heating power of the electric heating tape according to the temperature deviation ΔT (ΔT=65°C-measured temperature), and uses the fuzzy PID algorithm to output a 0-10V control signal to adjust the conduction ratio of the solid-state relay, so that the heating power is dynamically adjusted within the range of 20%-100%. When the temperature is ≥70°C, the power supply of the electric heating tape is immediately cut off; at the same time, the intelligent control module starts the blower of the ventilation duct according to the temperature gradient data (when the temperature difference between the top and bottom layers is greater than 5°C), and the fan is turned on at a speed of 1000m 3 / h air volume for 30 minutes to solve the problem of uneven temperature in the local area of ​​the pile and ensure that the error of the uniformity of the temperature field of the pile is ≤±2℃.

[0035] The intelligent control module also integrates a 4G wireless communication module (model MC20), which establishes a connection with the cloud server via the TCP / IP protocol. Users can view the photovoltaic power generation (accuracy ±0.1kWh), battery energy storage status (SOC display accuracy ±1%), stack temperature curve (sampling interval 10 minutes) and equipment operation log in real time through the mobile phone app; when the system has an abnormality (such as temperature sensor failure, battery overcharge, etc.), the intelligent control module automatically generates a fault code (such as E01 for temperature exceeding the upper limit) and pushes it to the user terminal, while simultaneously activating the backup control strategy (such as activating the backup temperature sensor), solving the problem of inconvenient equipment maintenance in cold regions and realizing remote fault diagnosis and emergency processing.

[0036] The intelligent control module has a built-in temperature change rate prediction model. Through differential calculation of historical temperature data and state space modeling, it can predict the temperature trend of the stack in advance. Specifically, it includes: The five-point central difference method is used to calculate the real-time temperature change rate. The formula is:

[0037] in For the moment The stack temperature detection value, is the sampling interval (set to 10 minutes), is the temperature change rate (°C / h). This algorithm improves noise suppression by 40%, solving the calculation error problem of the traditional differential method under low temperature fluctuations in cold regions. Construct a state equation containing temperature trend terms and disturbance terms:

[0038] The state vector , is the temperature acceleration compensation term, and are process noise and observation noise (both follow normal distribution and ), by iteratively updating the state estimate through Kalman filtering, the prediction accuracy of temperature change in the next 2 hours can reach ±1.5℃; Predictive control strategy: When the prediction model shows that the pile temperature will drop below 65℃ within 1 hour, the intelligent control module starts the electric heating cable in advance and increases the heating power to 120% of the rated value, and starts the blower at 1500m 3 / h air volume pre-ventilation solves the lag problem of traditional feedback control and improves temperature response speed.

[0039] The intelligent control module builds a multi-parameter correlation anomaly diagnosis model. By cross-checking the heating unit power consumption-temperature response curve, the blower air volume-oxygen concentration gradient, and sensor data, it can achieve real-time identification of equipment anomalies. Specifically, it includes: Heating unit abnormality diagnosis: Establishing power consumption-temperature transfer function model:

[0040] in is the steady-state gain (under normal operating conditions ), is the lag time (normally 15-20 minutes), is the time constant (normally 40-50 minutes). When the measured transfer function parameter deviates from the normal value by ±20%, it is determined that the electric heating cable is aging or has poor contact. For example, when When the heating efficiency drops, the alarm is triggered; Blower abnormality diagnosis: using the oxygen concentration gradient variation coefficient method:

[0041] in is the standard deviation of oxygen concentration at the corresponding positions of the three-layer temperature sensors, is the average value, under normal working conditions ,when If the condition persists for more than 10 minutes, it is determined that the blower impeller is dusty or the pipe is blocked. For example, if the air volume drops by 20%, will rise to over 30%; Temperature sensor anomaly diagnosis: Constructing a three-layer sensor data mutual verification matrix:

[0042] Calculate the residual vector ,when ( is the residual standard deviation, normally 0.5°C), it is determined that the corresponding sensor is drifting or disconnected. For example, when the sensor deviation of a certain layer is 4°C The temperature will exceed 1.5℃, triggering the sensor failover logic and automatically enabling the backup sensor channel.

[0043] Specific usage is illustrated in a village with an average winter temperature of -20°C, an extreme low of -35°C, and 2,400 hours of annual sunshine. A 220L composting system is installed in a farmer's courtyard. A double-layer insulation barrel (1.2mm thick inner layer of 304 stainless steel, 0.5mm thick outer layer of color-coated steel, with a 10cm center filling of polyurethane foam) is used. A 5.8-meter medium-temperature, self-regulating electric heating cable (24V / 60W) is spirally wound around the barrel's inner wall at 12cm intervals. The heating cable is wrapped with insulating and reflective film to minimize heat loss. A 30cm x 40cm electric discharge gate is installed at a 15° angle at the bottom, and the gate motor is electrically connected to the intelligent control module.

[0044] Build a bracket 3 meters above the compost bin and install a 2m 2 Monocrystalline silicon solar panels (conversion efficiency 22%), the tilt angle is adjusted according to the local latitude 45°+5°, through 4mm 2 The PV cables are connected to the inverter modules.

[0045] A sodium-ion battery energy storage box (2KW / 5kWh) is fixed to the side wall of the compost bin, and a BMS battery management system is installed inside the box. An intelligent control module (Siemens S7-200 SMART) is installed above the battery box and connects various sensors and actuators via an RS485 bus.

[0046] The photovoltaic modules output 24V DC power, which, after MPPT tracking by the inverter (98% efficiency), directly powers the heating cables at a primary current (operating at full 60W). Simultaneously, they charge the sodium-ion batteries at a 0.5C current (1A), switching to constant voltage charging when the SOC reaches 90%. For example, on a given day with ample sunlight from 8:00 AM to 4:00 PM, the photovoltaic panels generate 3.2kWh of electricity, of which 2.4kWh is used for heating and 0.8kWh is stored in the batteries, achieving 100% energy self-sufficiency.

[0047] When the PV output power is insufficient, the inverter switches to the second current mode (charging current 0.2C), and the sodium-ion battery provides supplemental power at the third current mode. For example, on a cloudy day from 10:00 AM to 2:00 PM, the PV generates only 0.5 kWh, while the battery releases 1.2 kWh to maintain heating, resulting in an 80% energy self-sufficiency rate. Only after 2:00 PM, when the battery SOC falls below 20%, does the system automatically connect to the mains (charging power 1 kW).

[0048] When the initial temperature of the pile is 5°C (ambient temperature -15°C), the three layers of Pt100 sensors (at 1 / 3, 1 / 2, and 2 / 3 of the pile height) detect an average temperature of 48°C. The intelligent control module starts the electric heating cable (60W) and the blower (air volume 1000m 3 / h); after 2 hours, the pile temperature rises to 65℃, and the electric heating tape switches to intermittent heating mode (20 minutes of shutdown every 1 hour of heating) to maintain the temperature at 65±2℃; when the ambient temperature drops to -25℃ at night, the insulation structure makes the temperature decay rate in the barrel ≤1℃ / h, and the sodium ion battery continuously supplies power to ensure that the temperature is not lower than 60℃; when the temperature detected by the sensor on a certain layer reaches 72℃, the control module immediately cuts off the power supply of the electric heating tape and starts strong ventilation (air volume 3000m 3 / h), after 30 minutes the temperature dropped to 68℃ and returned to normal control.

[0049] Take a 220L drum filled with 180L of mixed organic waste with a moisture content of 60% as an example: The heating cable is wound in a spiral with a pitch of 15cm from the bottom of the drum upwards, with a total length of 5.8 meters, covering 80% of the drum wall. When the surface temperature is 70±5℃, the temperature of the drum body 10cm away from the heating cable can reach 65℃. Abnormal temperature response: When the temperature of a sensor on a certain floor (such as at 1 / 3 height) rises by 5°C within 10 minutes (exceeding the normal rate of 2°C / 10 minutes), the control module activates the temperature change rate prediction model, calculates that the temperature will reach 75°C in the next hour, and reduces the power of the electric heating cable to 40W in advance to avoid local overheating.

[0050] The ventilation duct uses a 20mm diameter PVC pipe, with a bottom grid spacing of 30cm and an opening diameter of 2mm (hole spacing of 25mm): When the oxygen concentration sensor detects a value less than 18%, the blower starts with variable frequency. If the concentration does not rise to 20% after 10 minutes, the air volume is gradually increased. On the third day of composting (high temperature period), the pile humidity rises to 65%, and the control module starts ventilation + heating combined control: the power of the electric heating tape is increased to 80%, and the blower runs at full power. After 4 hours, the humidity drops to 60%.

[0051] Set the target stack temperature to 65°C. When the actual measured temperature is 60°C, the temperature deviation ΔT = 5°C, the deviation change rate Δv = 1°C / 10 min, and the fuzzy controller outputs PID parameters: Kp = 1.2, Ki = 0.3, Kd = 0.1. Calculate the heating power: P = 60W × (1 + ΔT × Kp + ∫ΔT × Ki dt + Δv × Kd) = 72W, and the power of the electric heating cable is increased by 20%. 20 minutes later, the temperature rises to 63°C, ΔT = 2°C, Δv = 0.5°C / 10 min, and the PID parameters are automatically adjusted to Kp = 0.8, Ki = 0.2, Kd = 0.05, and the power is reduced to 66W, achieving precise temperature control without overshoot.

[0052] At 9:00 AM on a weekday, after the heating cables had been running for 30 minutes, the stack temperature rose by only 2°C (the normal rise should be 5°C). The control module calculated the power consumption-temperature transfer function, K, as 0.4°C / W (normal 0.8°C / W), determining that the heating cables were partially aged. This triggered an alarm and activated the backup heating circuit (reserving 10% heating cable redundancy). The data from the three sensors were 65°C, 70°C, and 66°C, respectively. The calculated mutual check matrix residual, e2, was 2.3°C, which was greater than 3×0.5°C. The middle sensor was determined to be drifting, and the system automatically switched to the backup sensor (one backup channel was reserved for each layer).

[0053] The above are only embodiments of the present invention. The invention is not limited to the fields involved in this implementation case. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field are aware of all common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the inspiration given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. The aerobic composting system for high-altitude cold regions based on the integration of photovoltaic storage and energy supply is characterized by: include: A compost bucket body, wherein a heating unit, a temperature sensor and a ventilation duct are provided inside the compost bucket body, and a discharge port is provided at the bottom of the compost bucket body; A photovoltaic power generation module, which is used to convert solar energy into light energy; an inverter module, the inverter module being electrically connected to the photovoltaic power generation module and having an MPPT (maximum power point tracking) function, for converting the DC power input by the photovoltaic power generation module into a first current or a second current, wherein the first current is used to directly power the heating unit; A sodium ion battery energy storage module is installed on the side of the compost bucket body and is used to receive the second current as a charging current or output a third current to power the heating unit; The intelligent control module is used to obtain the photovoltaic power and battery energy storage status, and obtain the stack temperature data through the temperature sensor. It executes the control strategy based on the fuzzy PID algorithm. When the light intensity is not less than the preset value, the photovoltaic power is used first to charge the battery. When the battery power is lower than the preset value, it automatically switches to the mains power to charge the sodium-ion battery energy storage module. The heating unit is controlled to start or stop according to the stack temperature data.

2. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 1 is characterized in that: The heating unit inside the compost bin body is a medium-temperature self-controlling electric heating cable. The electric heating cable is spirally wound around the inner wall of the compost bin body with a winding spacing of 10-15 cm. The total length is 5.8 meters, the rated power is 60W, and the operating voltage is 24V safety voltage. The maximum maintenance temperature of the electric heating cable is 65°C, and the surface temperature is controlled at 70±5°C. When the compost body temperature exceeds 70°C, the power is automatically cut off through the linkage control of the temperature sensor and the intelligent control module. When it is lower than 65°C, heating is automatically started.

3. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 2 is characterized in that: The temperature sensor is a high-precision Pt100 thermal resistor sensor, which is distributed in three layers inside the compost bin, respectively set at 1 / 3, 1 / 2 and 2 / 3 of the pile height. Each layer has 2-3 sensors evenly arranged to monitor the temperature data at different depths of the pile in real time and transmit it to the intelligent control module.

4. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 3 is characterized in that: The ventilation duct is made of PVC and is laid in a grid pattern at the bottom of the compost barrel body. The duct diameter is 10-15mm, and ventilation holes with a diameter of 2-3mm are opened on the surface, with a hole spacing of 20-30mm. The ventilation duct is connected to an external blower through a duct joint; the blower is a variable frequency centrifugal fan, and the intelligent control module is controlled and connected to the variable frequency centrifugal fan. The variable frequency centrifugal fan uniformly delivers air to the pile through the bottom ventilation holes according to the control instructions of the intelligent control module, thereby meeting the oxygen needs of aerobic microorganisms and reducing the humidity of the pile through air circulation.

5. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 4 is characterized in that: The discharge port at the bottom of the compost barrel body is designed with an inclination angle of 15°-20° and a width of 30-40 cm. An electric gate is installed inside, and the electric gate is electrically connected to the intelligent control module.

6. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 5 is characterized in that: The intelligent control module is also used to output a PWM pulse signal to control the operation of the inverter's MPPT module when the light intensity sensor detects a value ≥ 200W / ㎡, thereby locking the maximum power point voltage of the photovoltaic array within the range of 24V±0.5V. At the same time, it sends a charging instruction to the BMS of the sodium-ion battery energy storage module, charging at a constant current of 0.5C until the battery SOC reaches 90%, and then switching to constant voltage charging; when the SOC of the sodium-ion battery energy storage module is less than 20%, the intelligent control module controls the mains charging circuit by closing the relay on the mains power supply circuit, and at the same time reduces the heating power of the electric heating cable to 60% of the rated power.

7. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 6 is characterized in that: The intelligent control module is also used to automatically calculate the heating power of the electric heating tape according to the temperature deviation ΔT when the three-layer three-dimensionally distributed Pt100 temperature sensors detect that the temperature of any layer is less than 65°C. ΔT is the difference between the actual measured temperature and 65°C. The fuzzy PID algorithm is used to output a control signal to adjust the heating power dynamically within the range of 20%-100%. When the temperature is ≥70°C, the power supply of the electric heating tape is immediately cut off. At the same time, based on the temperature gradient data, the intelligent control module starts the blower of the ventilation duct when the temperature difference between the top and bottom layers is greater than 5°C.

8. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 7 is characterized in that: The intelligent control module has a built-in temperature change rate prediction model. By differential calculation of historical temperature data and state space modeling, it can predict the temperature trend of the stack in advance, including the following contents: The five-point central difference method is used to calculate the real-time temperature change rate. The formula is: ； in For the moment The stack temperature detection value, is the sampling interval, is the temperature change rate; Construct a state equation containing temperature trend terms and disturbance terms: ； The state vector , is the temperature acceleration compensation term, and are process noise and observation noise, respectively, both of which obey normal distribution and , iteratively update the state estimate through Kalman filtering; The intelligent control module is also used to start the electric heating tape in advance and increase the heating power to the rated power when the prediction model shows that the pile temperature will drop below 65°C within 1 hour. At the same time, it starts the blower for ventilation to improve the temperature response speed.

9. The aerobic composting system for high-altitude cold regions based on integrated photovoltaic storage and energy supply according to claim 8 is characterized in that: The intelligent control module is also used to build a multi-parameter correlation abnormality diagnosis model. By verifying the heating unit power consumption-temperature response curve, the blower air volume-oxygen concentration gradient, and sensor data, it can realize real-time identification of equipment abnormalities. Specifically, it includes: Establish the power consumption-temperature transfer function model: ； in is the steady-state gain, under normal working conditions , It is the lag time. Normally it is 15-20 minutes. The time constant is 40-50 minutes normally. When the measured transfer function parameter deviates from the normal value by ±20%, it is determined that the electric heating cable is aging or has poor contact. When the heating efficiency drops, the alarm is triggered; The oxygen concentration gradient coefficient of variation method is used: ； in is the standard deviation of oxygen concentration at the corresponding positions of the three-layer temperature sensors, is the average value, under normal working conditions ,when If the condition persists for more than 10 minutes, it is determined that the blower impeller is dusty or the pipe is clogged; Construct a three-layer sensor data mutual verification matrix: ； Calculate the residual vector ,when hour, is the residual standard deviation, normally 0.5°C, which is used to determine whether the corresponding sensor is drifting or disconnected.

10. Aerobic composting method for high-altitude cold regions based on integrated solar energy storage and energy supply, characterized in that: A system as claimed in any one of claims 1 to 9 is employed.

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