Freezing dryer energy-saving control method and system based on reinforcement learning
By using reinforcement learning to optimize the pressurization and cooling processes of refrigerated air dryers, the problems of energy waste and wear in traditional refrigerated air dryers under dynamic operating conditions are solved, achieving more efficient energy utilization and extended equipment life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DAFENG TIANER MACHINERY
- Filing Date
- 2026-01-26
- Publication Date
- 2026-04-21
AI Technical Summary
Traditional refrigerated dryers rely on manual parameter settings for operation control, making it difficult to respond to dynamic changes in operating conditions, resulting in energy waste and equipment wear, and failing to achieve efficient energy consumption management.
By employing a reinforcement learning-based approach, an energy efficiency point coordinate system is established by acquiring air temperature and volume data, a fitting curve is generated, the target time and volume are calculated, and the pressurization and cooling processes are optimized to achieve intelligent control.
It improves the unit energy consumption ratio, reduces energy loss and equipment wear, and enhances the stability and reliability of the system.
Smart Images
Figure CN121900182A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of reinforcement learning technology, specifically to an energy-saving control method and system for refrigerated dryers based on reinforcement learning. Background Technology
[0002] As a core device in compressed air post-processing systems, the refrigerated air dryer's core function is to achieve deep dehydration of compressed air through heat exchange and refrigeration technology. Its working principle can be broken down into three key stages. First, the high-temperature, high-humidity compressed air enters the pre-cooler, where it undergoes reverse heat exchange with the pre-treated, low-temperature, dry air, achieving initial cooling and recovering some of the cooling capacity. Then, the pre-treated air is transported to the evaporator, where, under the forced cooling effect of the refrigerant, the air temperature drops sharply below the dew point, causing the saturated water vapor to condense efficiently into liquid water droplets. Finally, after being filtered by the air-water separator, the condensate is discharged from the system through an automatic drainage device, while the dried cold air returns to the pre-cooler for recycling, forming an energy closed loop.
[0003] However, traditional refrigerated air dryers have significant technical limitations within the existing technological system. Although equipped with basic components such as temperature control valves, their operation control remains at the level of mechanical adjustment, requiring manual parameter setting and making it difficult to respond to the dynamic operating conditions commonly encountered in compressed air systems. Due to the lack of intelligent sensing and closed-loop control systems, the equipment operates in a fixed parameter mode for extended periods. When the actual air volume processed is lower than the design threshold, the evaporator may over-cool, leading to energy waste; conversely, under high-load scenarios, insufficient cooling capacity may cause the exhaust dew point to exceed the standard. This extensive management directly results in a significant decrease in unit energy consumption ratio, further exacerbating energy loss and equipment wear. Summary of the Invention
[0004] The purpose of this invention is to provide an energy-saving control method and system for refrigerated dryers based on reinforcement learning, thereby solving the above-mentioned technical problems.
[0005] The objective of this invention can be achieved through the following technical solutions: A reinforcement learning-based energy-saving control method for refrigerated air dryers includes the following steps: S1: Obtain the temperature W and volume V of the air to be processed, and instruct the pressurizing device to pressurize the air to be processed at its rated power. Construct the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; S2: Obtain the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v tThe compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; S3: Establish a coordinate system with the time of the pressurization process as the x-axis and the total energy consumption as the y-axis. Construct an energy efficiency point D(t, E) in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; S4: Instruct the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .
[0006] As a further aspect of the present invention: in step S1, based on volume v t Methods for calculating the compression power E1 at time t using equation P(v) include: Obtain the cross-sectional area S of the compression device, and calculate the moving distance L = (Vv) t ) / S, calculate compression power consumption Where η1 represents the preset air compression efficiency, 0 < η1 < 1.
[0007] As a further aspect of the present invention: in step S4, a minimum pressure threshold P is preset. min The volume v of the air to be processed s Substituting into the equation P(v) yields P(v) s If P(v) s ) < P min Then, the pressure is continuously increased at the rated power until the pressure of the air to be treated is equal to the minimum pressure threshold.
[0008] As a further aspect of the present invention: in step S4, based on temperature w s The standard dew point temperature W was measured. min The methods specifically include: The preset temperature gradient is K = μ × k, where μ represents the preset gradient coefficient, μ = 1, 2, ..., and k represents the preset minimum temperature change value. The air to be processed is according to w s -K is gradually cooled down, and the relative humidity (RH) of the air to be treated is obtained after each cooling step. Cooling is stopped when the relative humidity (RH) reaches 100% and condensation occurs. The temperature at this point is recorded as the standard dew point temperature (W). min .
[0009] As a further aspect of the present invention: in step S2, based on the temperature difference and volume v t Methods for calculating the cooling power consumption E2 at time t include: Obtain the density ρ of the pressurized air and calculate the cooling power consumption. Where c represents the specific heat capacity of the air to be treated, η2 represents the preset cooling efficiency, and 0 < η2 < 1.
[0010] As a further aspect of the present invention: in step S4, the pressure tolerance limit P of the pressurizing device is obtained. max The target pressure P (v) s ) < P max .
[0011] As a further aspect of the present invention: in step S3, when there are points in the fitted curve where the total energy consumption is equal, the point with the shorter time consumption is selected as the target time.
[0012] A reinforcement learning-based energy-saving control system for a refrigerated dryer includes: Simulation module: Obtains the temperature W and volume V of the air to be processed, instructs the pressurization device to pressurize the air to be processed at its rated power, and constructs the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; Temperature module: acquires the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v t The compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; Pressure module: A coordinate system is established with the moment during the pressurization process as the x-axis and the total energy consumption as the y-axis. An energy efficiency point D(t, E) is constructed in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; Adjustment module: Instructs the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .
[0013] The beneficial effects of this invention are as follows: First, the raw gas data of the air to be treated is obtained, including temperature and volume. This temperature and volume are crucial for adjusting the parameters of the refrigerated dryer. Then, a preliminary operation is performed by pressurizing the air. Pressurizing the air serves two purposes: firstly, from a practical standpoint, atmospheric pressure is impractical, and pressurization is necessary in most cases; secondly, pressurization increases the dew point temperature of the gas, facilitating the subsequent removal of water vapor. However, it's important to note that pressurization causes the gas to do work, leading to a temperature increase. Furthermore, as the pressure increases, further pressurization requires more energy. Therefore, while pressurization helps raise the dew point temperature and reduce energy consumption for subsequent cooling, a comprehensive consideration is necessary. Finally, based on a specific example of how pressurized air pressure changes with its volume, the compression power consumption for air compression is calculated.
[0014] Next, the temperature of the pressurized air is obtained. This temperature will be higher than the temperature before pressurization because the gas does work. Therefore, it needs to be measured again to ensure accuracy. Then, the standard dew point temperature of the pressurized air at the current pressure needs to be measured. Here, the standard dew point temperature needs to be re-determined based on the pressurized air. The standard dew point temperature is found step by step by setting a temperature gradient. Although there is some error in finding the standard dew point temperature by using a temperature gradient, it can greatly reduce the workload. Then, the cooling power consumption is calculated based on the temperature difference and the volume of the pressurized air. There are two points to note here. Cooling the pressurized air is affected by both volume and temperature. This echoes the previous compression. Although compressing the gas causes the gas temperature to rise due to the work done, the volume of the compressed gas decreases, thus reducing the power consumption used for cooling. The second factor of temperature is easy to understand: the higher the temperature, the greater the energy consumption for cooling.
[0015] To more clearly select the optimal adjustment scheme, a coordinate system is generated with the pressurized air volume as the x-axis and the total energy consumption as the y-axis. A corresponding fitting curve is then generated within this coordinate system, and the fitting equation corresponding to the curve is obtained. The target volume corresponding to the minimum value in the fitting equation is selected, and the target pressure is calculated. Adjustments are made based on the obtained target volume and target pressure, increasing the pressure of the air to be processed. After compression, the temperature is lowered to the standard dew point temperature, thus completing the energy-saving control of the refrigerated dryer. This invention, by adjusting based on target volume and target pressure, improves the unit energy consumption ratio and reduces energy loss and equipment wear. Attached Figure Description
[0016] The invention will now be further described with reference to the accompanying drawings.
[0017] Figure 1 This is a flowchart illustrating an energy-saving control method and system for refrigerated dryers based on reinforcement learning, as described in this invention. Detailed Implementation
[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Please see Figure 1 As shown, this invention is an energy-saving control method for refrigerated dryers based on reinforcement learning, comprising the following steps: S1: Obtain the temperature W and volume V of the air to be processed, and instruct the pressurizing device to pressurize the air to be processed at its rated power. Construct the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; S2: Obtain the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v t The compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; S3: Establish a coordinate system with the time of the pressurization process as the x-axis and the total energy consumption as the y-axis. Construct an energy efficiency point D(t, E) in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; S4: Instruct the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .
[0020] It's important to note that the first step in air treatment is to obtain the raw gas data of the air to be treated. This raw gas data includes two key parameters: temperature and volume. Temperature, as an important indicator of the thermodynamic state of air, reflects the intensity of the thermal motion of air molecules; while volume directly reflects the size of the space occupied by the air. This temperature and volume data are crucial for subsequent adjustments to the parameters of the refrigerated dryer, helping us to more accurately grasp the characteristics of the air. After obtaining the raw gas data, the initial operational step is to pressurize the air. From a practical perspective, under normal pressure, some characteristics of air and the treatment effect may not be ideal, rendering it impractical. In most real-world applications, to meet specific process requirements or achieve the desired treatment effect, air often needs to be pressurized before use.
[0021] On the other hand, pressurization is crucial for raising the dew point temperature of gases. In air handling processes, the presence of water vapor often causes numerous problems, but pressurization can effectively increase the dew point temperature of the gas. This is because when a gas is compressed, the distance between molecules decreases, and the intermolecular interactions strengthen, making it easier for water vapor to condense into liquid water. This facilitates subsequent removal of water vapor from the air using appropriate methods, thereby improving the dryness of the air and meeting the needs of various production and applications.
[0022] However, it's important to note that pressurization is not without its costs. During pressurization, the compression and collisions between gas molecules cause the gas to do work, leading to a temperature increase. This temperature rise can negatively impact subsequent processing. As the pressure gradually increases, the energy required for further pressurization also increases significantly. This is because under high pressure, the repulsive forces between gas molecules strengthen, requiring greater resistance to overcome and thus consuming more energy to continue compressing the gas.
[0023] Therefore, although pressurization offers numerous advantages in increasing gas dew point temperature and reducing energy consumption for subsequent cooling, a comprehensive consideration of various factors is necessary in practical operation. It's crucial to fully leverage the benefits of pressurization while minimizing energy waste and other potential problems. Accurate calculation of compression power consumption allows for a better assessment of the energy cost of pressurization, thereby optimizing the processing flow and achieving optimal energy utilization and air treatment performance.
[0024] After pressurizing the air to be processed, the next step is to obtain its temperature. During pressurization, gas molecules do work by compressing each other, increasing the gas's internal energy according to thermodynamic principles, thus raising its temperature. Therefore, the temperature of the pressurized air will inevitably be higher than its temperature before pressurization. This temperature change has a significant impact on subsequent processing, so it is necessary to measure it again to ensure the accuracy and reliability of the obtained temperature data.
[0025] After obtaining the temperature of the pressurized air, it is also necessary to measure the standard dew point temperature of the pressurized air at the current pressure. It is important to note that the state of the air changes after pressurization, and its physical properties differ from those of the unpressurized air. Therefore, the standard dew point temperature must be re-determined based on the pressurized air; the data from the unpressurized air cannot be directly used. To determine the standard dew point temperature of the pressurized air, a temperature gradient is used to find it step by step.
[0026] After determining the standard dew point temperature of the pressurized air, the cooling power consumption can be calculated based on the temperature difference and the volume of the pressurized air. Two key factors require special attention here. First, cooling pressurized air is affected by both volume and temperature, which closely corresponds to the compression process. During compression, the gas does work, causing its temperature to rise, but simultaneously its volume decreases. This decrease in gas volume means that less air needs to be processed during the subsequent cooling process, and according to the principle of energy conservation, the power consumption for cooling is correspondingly lower. Under the same temperature conditions, a smaller volume of gas carries less heat, and the energy required to cool it to the same temperature is naturally less. Second, the effect of temperature on cooling power consumption is intuitive and easy to understand. Simply put, the higher the temperature, the more heat the air carries; to cool the high-temperature air to the set temperature, more energy is needed to transfer this heat.
[0027] After completing the aforementioned series of operations and acquiring relevant data, in order to more intuitively and significantly select the optimal option from numerous possible adjustment schemes, a coordinate system will be constructed with pressurized air volume as the x-axis and total energy consumption as the y-axis. Based on the previously measured and calculated total energy consumption data corresponding to different pressurized air volumes, corresponding fitting curves will be generated.
[0028] Obtain the fitting equation corresponding to the fitted curve. This fitting equation helps to understand the intrinsic relationship between pressurized air volume and total energy consumption. Next, select the target volume corresponding to the minimum value in the fitting equation. The target volume represents the pressurized air volume that theoretically minimizes total energy consumption under specific conditions.
[0029] After determining the target volume, the corresponding target pressure is calculated based on relevant physical principles and engineering calculation formulas. This yields two crucial parameters: the target volume and the target pressure. Subsequently, based on these target volume and pressure, the air to be processed is finely adjusted. Specifically, the pressure of the air is gradually increased, moving it closer to the target pressure. Once the compression process is successfully completed, the cooling system is appropriately controlled to lower the temperature to the previously measured standard dew point temperature. This completes the energy-saving control of the refrigerated dryer.
[0030] This invention adjusts the target volume and pressure based on calculations and data analysis. This adjustment method is based on the relationship between multiple factors, including pressurized air volume, total energy consumption, temperature, and pressure. This effectively improves the unit energy consumption ratio, ensuring that every unit of energy input generates greater benefits. Simultaneously, by avoiding unnecessary over-compression and unreasonable energy consumption, energy loss is significantly reduced. Furthermore, with the equipment operating in a more scientific and rational manner, wear between its components is effectively controlled, extending the equipment's service life and further enhancing the stability and reliability of the entire system.
[0031] In another preferred embodiment of the invention, based on volume v t Methods for calculating the compression power E1 at time t using equation P(v) include: Obtain the cross-sectional area S of the compression device, and calculate the moving distance L = (Vv) t ) / S, calculate compression power consumption Where η1 represents the preset air compression efficiency, 0 < η1 < 1.
[0032] It is worth noting that while pressurization offers advantages such as increasing gas dew point temperature and reducing energy consumption for subsequent cooling, various factors need to be considered comprehensively during actual operation. The benefits of pressurization must be fully utilized while minimizing energy waste and other potential problems. Accurate calculation of compression power consumption allows for a better assessment of the energy cost of pressurization, thereby optimizing the processing flow and achieving optimal energy efficiency and air treatment performance.
[0033] In another preferred embodiment of the present invention, a minimum pressure threshold P is preset. min The volume v of the air to be processed s Substituting into the equation P(v) yields P(v) s If P(v) s ) < P min Then, the pressure is continuously increased at the rated power until the pressure of the air to be treated is equal to the minimum pressure threshold.
[0034] Understandably, in practical applications, air needs to be pressurized to a certain level to be of practical use. In industrial production, many pneumatic devices, such as cylinders and pneumatic wrenches, can only operate normally and perform optimally when the air reaches a specific pressure value. If the air pressure is insufficient, these devices may not be able to generate enough power to complete the corresponding work tasks, or may even experience unstable operation.
[0035] In another preferred embodiment of the invention, based on temperature w s The standard dew point temperature W was measured. min The methods specifically include: The preset temperature gradient is K = μ × k, where μ represents the preset gradient coefficient, μ = 1, 2, ..., and k represents the preset minimum temperature change value. The air to be processed is according to w s -K is gradually cooled down, and the relative humidity (RH) of the air to be treated is obtained after each cooling step. Cooling is stopped when the relative humidity (RH) reaches 100% and condensation occurs. The temperature at this point is recorded as the standard dew point temperature (W). min .
[0036] In another preferred embodiment of the present invention, based on temperature difference and volume v t Methods for calculating the cooling power consumption E2 at time t include: Obtain the density ρ of the pressurized air and calculate the cooling power consumption. Where c represents the specific heat capacity of the air to be treated, η2 represents the preset cooling efficiency, and 0 < η2 < 1.
[0037] It should be noted that by gradually changing the temperature according to a set gradient and observing the changes in the air state until the critical temperature at which the air just reaches saturation and water vapor begins to condense is found, this critical temperature is the standard dew point temperature. Although this method of finding the standard dew point temperature through a temperature gradient has some errors, such as limited precision in temperature control and interference from measuring instrument errors, which may cause a certain deviation between the measured dew point temperature and the actual value, this method has significant advantages. It can greatly reduce the workload, thus meeting the needs of practical engineering applications.
[0038] In another preferred embodiment of the present invention, the pressure tolerance limit P of the pressurizing device is obtained. max The target pressure P (v) s ) < P max .
[0039] Understandably, in practical applications, for safety reasons, it is essential to ensure that the target pressure of the pressurizing equipment is strictly below its pressure tolerance limit. This is because the internal air pressure of the pressurizing equipment continuously increases during operation. If the target pressure is set too high, approaching or even exceeding the equipment's own pressure tolerance limit, the equipment will be in an extremely dangerous state.
[0040] In another preferred embodiment of the present invention, when there are points in the fitted curve where the total energy consumption is equal, the point with the shorter time consumption is selected as the target time.
[0041] It is worth noting that when there are points in the fitted curve where the total energy consumption is equal, the target volume needs to be selected according to specific principles. In this case, the smaller pressurized air volume should be selected as the target volume. This is because, with the same total energy consumption, a smaller pressurized air volume means that while achieving the same energy-saving effect, the required equipment size is smaller, the space occupied is less, and the requirements for system complexity and operating costs are lower.
[0042] A reinforcement learning-based energy-saving control system for a refrigerated dryer includes: Simulation module: Obtains the temperature W and volume V of the air to be processed, instructs the pressurization device to pressurize the air to be processed at its rated power, and constructs the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; Temperature module: acquires the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v t The compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; Pressure module: A coordinate system is established with the moment during the pressurization process as the x-axis and the total energy consumption as the y-axis. An energy efficiency point D(t, E) is constructed in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; Adjustment module: Instructs the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .
[0043] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the present invention.
Claims
1. A method for energy-saving control of a refrigerated dryer based on reinforcement learning, characterized in that, Includes the following steps: S1: Obtain the temperature W and volume V of the air to be processed, and instruct the pressurizing device to pressurize the air to be processed at its rated power. Construct the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; S2: Obtain the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v t The compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; S3: Establish a coordinate system with the time of the pressurization process as the x-axis and the total energy consumption as the y-axis. Construct an energy efficiency point D(t, E) in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; S4: Instruct the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .
2. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S1, based on volume v t Methods for calculating the compression power E1 at time t using equation P(v) include: Obtain the cross-sectional area S of the compression device, and calculate the moving distance L = (Vv) t ) / S, calculate compression power consumption Where η1 represents the preset air compression efficiency, 0 < η1 < 1.
3. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S4, a minimum pressure threshold P is preset. min The volume v of the air to be processed s Substituting into the equation P(v) yields P(v) s If P(v) s ) < P min Then, the pressure is continuously increased at the rated power until the pressure of the air to be treated is equal to the minimum pressure threshold.
4. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S4, based on temperature w s The standard dew point temperature W was measured. min The methods specifically include: The preset temperature gradient is K = μ × k, where μ represents the preset gradient coefficient, μ = 1, 2, ..., and k represents the preset minimum temperature change value. The air to be processed is according to w s -K is gradually cooled down, and the relative humidity (RH) of the air to be treated is obtained after each cooling step. Cooling is stopped when the relative humidity (RH) reaches 100% and condensation occurs. The temperature at this point is recorded as the standard dew point temperature (W). min .
5. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S2, based on temperature difference and volume v t Methods for calculating the cooling power consumption E2 at time t include: Obtain the density ρ of the pressurized air and calculate the cooling power consumption. Where c represents the specific heat capacity of the air to be treated, η2 represents the preset cooling efficiency, and 0 < η2 < 1.
6. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S4, the pressure tolerance limit P of the pressurizing device is obtained. max The target pressure P (v) s ) < P max .
7. The energy-saving control method for a refrigerated dryer based on reinforcement learning according to claim 1, characterized in that, In step S3, when there are points in the fitted curve where the total energy consumption is equal, the point with the shorter time consumption is selected as the target time.
8. An energy-saving control system for a refrigerated dryer based on reinforcement learning, characterized in that, include: Simulation module: Obtains the temperature W and volume V of the air to be processed, instructs the pressurization device to pressurize the air to be processed at its rated power, and constructs the equation corresponding to the change in pressure of the air to be processed with volume v during the pressurization process. , where P sta represents the pressure of the air to be processed before pressurization, and w represents the temperature corresponding to the volume v of the air to be processed; Temperature module: acquires the temperature w of the air to be processed at time t during the pressurization process. t and volume v t Based on volume v t The compression power E1 at time t is calculated using equation P(v); Calculate temperature difference Based on temperature difference and volume v t Calculate the cooling power consumption E2 at time t; Pressure module: A coordinate system is established with the moment during the pressurization process as the x-axis and the total energy consumption as the y-axis. An energy efficiency point D(t, E) is constructed in the coordinate system, where E represents the total energy consumption and E = E1 + E2. Energy efficiency points are repeatedly constructed and fitted curves are generated at preset intervals, and the fitting equation E(t) corresponding to the fitted curves is obtained. The minimum total energy consumption E in the fitted equation E(t) is obtained. min The corresponding x-axis coordinates are marked as the target time t. s ; Adjustment module: Instructs the pressurizing equipment to pressurize to the target time t at rated power. s Get the volume v of the air to be processed at this time. s and temperature w s Based on temperature w s The standard dew point temperature W was measured. min After pressurization is complete, cool the temperature to w. s .