A method and system for operating a heat pump system for brewing

Abstract

This invention belongs to the field of heat pump technology, specifically a method and system for operating and controlling a heat pump system used in brewing. The method includes synchronously acquiring multi-dimensional parameters such as steam temperature, hot water temperature, and heat pump power; establishing a heat demand-power coupling mapping relationship; calculating the optimal variable power shutdown coefficient to drive the heat source heat pump to perform a step-decreasing gradual shutdown; real-time monitoring of power change rate and dynamic adjustment of shutdown parameters; continuous monitoring of sudden changes in heat demand and reassessment of start-up and shutdown requirements; and the system includes a multi-modal parameter acquisition unit, an operation control unit, a heat pump drive control unit, a steam parameter monitoring unit, and a system protection control unit. This application can achieve precise matching between heat pump power and system heat demand, controlling power fluctuations within 20% of the original shutdown method, eliminating grid impact and power drops, extending equipment lifespan, and ensuring the stability of distillation process parameters.

Description

Technical Field

[0001] This invention belongs to the field of heat pump technology, specifically a method and system for operating and controlling a heat pump system used in brewing. Background Technology

[0002] Steam heat pump technology enables the efficient utilization of low-grade heat energy in stages. It can produce high-temperature steam and form an energy closed loop by combining it with waste heat recovery in brewing processes. It is widely used in steam-demanding industries such as brewing and is a key technology for improving energy utilization and reducing energy consumption in the brewing industry.

[0003] Existing steam heat pump systems for brewing require the assistance of a heat source heat pump to establish a stable working cycle. They generally adopt a discrete start-stop control strategy based on a single temperature threshold to control the start-stop of the heat source heat pump, which can complete the basic start-up and steam supply operations of the system.

[0004] The existing single-temperature discrete start-stop control strategy has fundamental technical defects. It is easy to cause the superposition of starting current and cause grid impact. The unsteady-state sudden stop of the heat source heat pump will accelerate the wear and aging of equipment and shorten its service life. At the same time, it will cause a sudden drop in system power and pulsation of steam parameters, which will damage the stability of the brewing distillation process and affect the quality of the wine. This seriously restricts the large-scale promotion and application of steam heat pump technology in the brewing industry.

[0005] Therefore, the present invention provides an operation control method and system for a heat pump system used in brewing. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is: a method for operating and controlling a heat pump system for brewing, comprising the following steps:

[0008] S1: By synchronously collecting the steam temperature at the outlet of the steam heat pump, the hot water temperature at the inlet of the steam heat pump, the hot water temperature at the outlet of the wine cooler, the power of the steam heat pump, the power of the source heat pump, the temperature of the hot water storage tank, and the outdoor ambient temperature through sensor units deployed at each key node of the system, a parameter dataset reflecting the multi-dimensional operating status of the brewing heat pump system is constructed.

[0009] S2: Calculate the heat demand-power coupling mapping relationship based on the parameter dataset, determine whether the steam heat pump can operate independently, if it can operate independently, trigger the source heat pump gradual shutdown control sequence, if it is determined that assistance is still needed, execute the variable power operation control strategy.

[0010] S3: Calculate the optimal variable power shutdown coefficient of the source heat pump according to the heat demand-power coupling mapping relationship, and drive the source heat pump to perform a gradual power shutdown based on the optimal variable power shutdown coefficient, reducing the source heat pump power in stages according to the preset step reduction range until it is completely shut down.

[0011] S4: During the gradual power shutdown process, the total power change rate of the system is monitored in real time. When the change rate exceeds the power fluctuation threshold, the step decrease amplitude and time interval are automatically adjusted to maintain a smooth transition of the system power curve.

[0012] S5: Continuously monitor the operating status of the steam heat pump and the waste heat supply capacity of the wine cooler. When a sudden change in heat demand is detected, reassess the start-up and shutdown requirements of the source heat pump and execute the corresponding control decisions.

[0013] The present invention also provides an operation control system for a heat pump system for brewing, including a multimodal parameter acquisition unit, an operation control unit, a heat pump drive control unit, a steam parameter monitoring unit, and a system protection control unit.

[0014] The multimodal parameter acquisition unit is configured to deploy sensor arrays at key nodes of the brewing heat pump system and is electrically coupled to the operation control unit through an edge computing gateway.

[0015] The operation control unit is electrically connected to the multimodal parameter acquisition unit, and integrates a multidimensional parameter fusion processing module and a system status evaluation module. The multidimensional parameter fusion processing module is responsible for receiving and preprocessing the raw data collected by the sensors, and the system status evaluation module is responsible for performing heat demand calculation, operation status determination and control strategy generation based on the preprocessed multidimensional parameter data.

[0016] The heat pump drive control unit is electrically connected to the operation control unit and is configured to perform start-stop control and power regulation of the steam heat pump and the source heat pump. The heat pump drive control unit integrates a variable power regulation module, a gradual shutdown control module and a multi-level power level management module.

[0017] The steam parameter monitoring unit forms a feedback connection with the heat pump drive control unit and the operation control unit, and is configured to perform real-time monitoring of steam pressure and temperature and feed back the monitoring data to the operation control unit to support the dynamic adjustment of the control strategy.

[0018] The system protection control unit forms a protection linkage connection with the heat pump drive control unit and the operation control unit, and is configured to monitor the transformer load status, execute cold start preheating control and heat pump protection logic.

[0019] Preferably, the temperature sensor array in the multimodal parameter acquisition unit includes a steam temperature sensor, a hot water temperature sensor, and an ambient temperature sensor. The steam temperature sensor has a range of 0 to 180 degrees Celsius and an accuracy of ±0.5 degrees Celsius; the hot water temperature sensor has a range of 0 to 90 degrees Celsius and an accuracy of ±0.2 degrees Celsius; and the ambient temperature sensor has a range of -40 to 60 degrees Celsius and an accuracy of ±0.5 degrees Celsius. Each sensor uses a corrosion-resistant protective shell to adapt to the high humidity and high corrosiveness of the brewing workshop environment.

[0020] Preferably, in step S1, the parameters collected by the system also include steam pressure, steam flow rate, refrigerant temperature of the wine cooler, refrigerant pressure of the wine cooler, and liquid level of the hot water storage tank. The monitoring accuracy of the steam pressure is ±0.005 MPa, the monitoring accuracy of the steam flow rate is ±0.5 cubic meters per hour, and the monitoring accuracy of the liquid level of the hot water storage tank is ±1 centimeter. The sampling period of each parameter data is uniformly set to one second to ensure the synchronization of multi-dimensional parameter data in the time dimension.

[0021] Preferably, in step S2, the establishment of the heat demand-power coupling mapping relationship adopts a data-driven modeling method based on Gaussian process regression. The modeling process uses the steam temperature and steam pressure at the outlet of the steam heat pump as the heat demand feature input, and the steam heat pump power and the source heat pump power as the power feature output. The mapping model is trained through historical operating data. The input feature vector dimension of the model is four to six features, and the output feature vector dimension is one to two power values. The root mean square error of the model prediction is controlled within three percent of the rated power.

[0022] Preferably, in step S3, the progressive power shutdown strategy adopts a stepped reduction control logic, with the stepped reduction amplitude set to 5% to 10% of the current power, the stepped time interval set to 30 to 60 seconds, and the total shutdown duration controlled within the range of 3 to 10 minutes to ensure a smooth transition effect of the power curve.

[0023] Preferably, the multi-level power level management module in the heat pump drive control unit is configured with at least three power levels: the high power level corresponds to 80% to 100% of the rated power, the medium power level corresponds to 40% to 60% of the rated power, and the low power level corresponds to 20% to 35% of the rated power. The switching time between each level is set to 5 to 15 seconds and a smooth transition algorithm is configured to eliminate the step impact during the power switching process.

[0024] Preferably, the system status assessment module in the operation control unit also integrates a steam pressure prediction algorithm. The prediction algorithm is implemented based on a long short-term memory neural network architecture. The network contains two long short-term memory layers and one fully connected output layer. The number of hidden layer units is set to 128 for each layer. The model input is the steam pressure time series data of the most recent 30 minutes, and the output is the predicted steam pressure value for the next 5 minutes. The average absolute error of the prediction algorithm is controlled within 0.01 MPa.

[0025] Preferably, the transformer load monitoring module in the system protection control unit monitors the transformer load rate in real time. When the load rate exceeds 80%, it automatically limits the starting power of the heat pump or forces a reduction in the power level. When the load rate exceeds 90%, it prohibits the heat pump from starting to prevent grid impact.

[0026] Preferably, the heat pump protection module in the system protection control unit monitors the number of consecutive start-stop cycles of the source heat pump. When the number of consecutive start-stop cycles exceeds three times within ten minutes, it automatically enters the heat pump protection mode. In the protection mode, the system locks the current state of the source heat pump and forces its minimum running time to be extended to thirty minutes.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. This invention collects multi-dimensional parameters such as the steam outlet temperature of the steam heat pump, the hot water temperature of the wine cooler, the heat pump power, and the outdoor ambient temperature in real time, and establishes a heat demand-power coupling mapping model. It can dynamically adjust the heat pump power output according to the actual heat demand, achieve precise matching between the heat pump operating power and the system heat demand, significantly improve the system's energy utilization efficiency, and reduce operating energy consumption.

[0029] 2. This invention uses a multi-level power level adjustment strategy to enable the steam heat pump to smoothly switch between different levels, rather than the traditional constant-speed start-stop operation mode. This effectively eliminates energy loss and equipment stress caused by frequent start-stop, and extends the service life of the equipment.

[0030] 3. This invention replaces the original simple temperature threshold-triggered immediate shutdown method with a gradual power shutdown strategy, achieving a smooth transition of heat source and heat pump power. The total power fluctuation is controlled within 20% of the original shutdown method, eliminating the system instability problem caused by sudden power drop.

[0031] 4. Through the synergistic effect of continuous monitoring of the operating status by the system status assessment module and the steam pressure prediction algorithm, this invention can predict the trend of heat demand changes in advance and execute preventive control decisions, thus ensuring the stability of distillation process parameters and the reliability of the quality of the distilled liquor. Attached Figure Description

[0032] The invention will now be further described with reference to the accompanying drawings.

[0033] Figure 1 This is a structural block diagram of the operation and control system of a heat pump system for brewing in this invention;

[0034] Figure 2 This is a flowchart of a method for controlling the operation of a heat pump system for brewing according to the present invention. Detailed Implementation

[0035] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0036] Example 1: This example applies to the operation and control scenario of a heat pump system in a brewing workshop. The brewing heat pump system in this scenario comprises two core components: a steam heat pump unit and a source heat pump unit. The steam heat pump generates high-temperature steam to drive the distillation kettle for raw material distillation, while the source heat pump recovers waste heat from the cooler and raises its temperature before supplying it to the steam heat pump as a low-temperature heat source. The system also includes a hot water storage tank, a pipeline network, and supporting control equipment. A complete operation and control system for the brewing heat pump system is also deployed in this scenario. This system senses the multi-dimensional operating status parameters of the steam heat pump and the source heat pump through a multi-modal parameter acquisition unit. The operation control unit calculates the heat demand and determines the status. The heat pump drive control unit executes the start-up, shutdown, and power adjustment of the steam heat pump and the source heat pump. A steam parameter monitoring unit provides real-time feedback on the steam status, and a system protection control unit monitors the transformer load and implements heat pump protection logic. Ultimately, this achieves coordinated and optimized control of the steam heat pump and the source heat pump, effectively eliminating the equipment lifespan loss and system power degradation problems caused by frequent start-up and shutdown of the heat source heat pump in existing technologies.

[0037] like Figure 1 As shown, the operation and control system of the brewing heat pump system includes five core functional units: a multimodal parameter acquisition unit, an operation control unit, a heat pump drive control unit, a steam parameter monitoring unit, and a system protection control unit. The five functional units are connected and interact with each other through a standardized data interface and communication link, forming a complete signal processing link from multi-dimensional parameter perception to heat pump drive control.

[0038] The multimodal parameter acquisition unit is configured to deploy sensing modules at key nodes of the brewing heat pump system. Electrically coupled to the operation control unit via an edge computing gateway, it enables real-time acquisition and preprocessing of multidimensional operating parameters. The sensing modules within this unit consist of a temperature sensing unit array and a power sensing unit array. The temperature sensing unit array includes three types of temperature sensors: steam temperature sensor, hot water temperature sensor, and ambient temperature sensor. The steam temperature sensor is installed at the steam heat pump outlet pipe to collect the temperature of the produced steam. Its range is set to 0 to 180 degrees Celsius, with a measurement accuracy of ±0.5 degrees Celsius. The sensor probe is made of corrosion-resistant stainless steel and features a threaded connection. The installation method is adapted to meet the installation requirements of high-pressure steam pipelines. The hot water temperature sensor is deployed in three key locations: the inlet pipe of the steam heat pump, the outlet pipe of the wine cooler, and inside the hot water storage tank. The range is set to 0 to 90 degrees Celsius, and the measurement accuracy is ±0.2 degrees Celsius. The sensor housing is made of food-grade stainless steel to meet the hygiene and corrosion resistance requirements of the brewing workshop. The ambient temperature sensor is installed on the outdoor side of the brewing workshop, with a range set to -40 to 60 degrees Celsius and a measurement accuracy of ±0.5 degrees Celsius. It is used to monitor the outdoor atmospheric temperature to assess the environmental heat exchange conditions of the heat pump unit. All temperature sensors use corrosion-resistant protective housings to adapt to the high humidity and high corrosiveness of the brewing workshop environment, and the housing protection level is not lower than IP65.

[0039] The power sensing unit array comprises two units: a steam heat pump power sensor and a source heat pump power sensor. These are installed in the power distribution lines of the steam heat pump unit and the source heat pump unit, respectively. The range of the power sensor is determined based on the rated power of each unit, with a measurement accuracy of ±0.5% of the rated power. The sampling frequency is set to 10 Hz to capture rapid power changes. The sensing module also includes a steam pressure sensor, a steam flow sensor, and a hot water storage tank level sensor. The steam pressure sensor is installed between the steam heat pump outlet pipe and the steam-using equipment inlet pipe, with a monitoring accuracy of ±0.005 MPa and a response time of less than 100 milliseconds to capture... To capture transient fluctuations in steam pressure, a steam flow sensor is installed on the main steam pipeline with a monitoring accuracy of ±0.5 cubic meters per hour. It is used to measure the actual steam delivery to assess the actual heat output of the system. A hot water storage tank level sensor is installed on the top of the hot water storage tank with a monitoring accuracy of ±1 centimeter. It adopts the ultrasonic level measurement principle to adapt to the steam environment inside the tank. The raw data collected by each sensor is processed by an edge computing gateway for data filtering, time synchronization, and format standardization before being transmitted to the operation control unit. The sampling period of each parameter data is uniformly set to one second to ensure the synchronization of multi-dimensional parameter data in the time dimension.

[0040] The operation control unit is electrically connected to the multimodal parameter acquisition unit and integrates a multidimensional parameter fusion processing module and a system status evaluation module. The operation control unit uses an industrial-grade programmable logic controller as its core computing platform and is equipped with a multi-core central processing unit and a dedicated floating-point coprocessor to support the real-time calculation of complex algorithms. The communication interfaces of the operation control unit include a gigabit Ethernet interface and an RS485 interface. The gigabit Ethernet interface is used for high-speed data communication with the edge computing gateway, and the RS485 interface is used for exchanging commands and status data with the heat pump drive control unit, the steam parameter monitoring unit, and the system protection control unit.

[0041] The multi-dimensional parameter fusion processing module is responsible for receiving and preprocessing the raw data collected by the sensor. The module integrates a digital filtering algorithm, an outlier removal algorithm, and a data interpolation algorithm. The digital filtering algorithm uses a second-order Butterworth low-pass filter to eliminate high-frequency noise interference in the sensor signal, with the cutoff frequency set to 0.5 Hz. The outlier removal algorithm performs real-time checks on the collected data based on the three-standard-deviation criterion in statistics. When a data point deviates from the moving average by more than three standard deviations, the data point is marked as an outlier and replaced with a linear interpolation result. The data interpolation algorithm performs linear interpolation during the outlier replacement and alignment with the edge of the sensor sampling period to ensure the temporal continuity of the data.

[0042] The system status assessment module is responsible for performing heat demand calculation, operating status determination, and control strategy generation based on preprocessed multi-dimensional parameter data. This module integrates two sub-modules: a heat demand calculation unit and a control strategy generation unit. The heat demand calculation unit calculates the actual heat demand power of the current system based on the collected steam temperature, steam pressure, and steam flow rate of the steam heat pump outlet. The calculation result serves as one of the input features of the heat demand-power coupling mapping model. The control strategy generation unit determines whether the steam heat pump can operate independently based on the output result of the heat demand-power coupling mapping model. If it is determined that it can operate independently, it triggers a gradual shutdown control sequence of the source heat pump. If it is determined that auxiliary operation is still required, it executes a variable power operation control strategy. This module also integrates a steam pressure prediction algorithm. The prediction algorithm is implemented based on a long short-term memory neural network architecture. The network contains two long short-term memory layers and one fully connected output layer. The number of hidden layer units in each of the two long short-term memory layers is set to 128. The model input is the steam pressure time series data of the most recent 30 minutes, and the output is the predicted steam pressure value for the next 5 minutes. The mean absolute error of the prediction algorithm is controlled within 0.01 MPa, which can predict the trend of heat demand changes in advance and support preventive control decisions.

[0043] The heat pump drive control unit is electrically connected to the operation control unit and is configured to perform start-stop control and power regulation of the steam heat pump and the source heat pump. The heat pump drive control unit integrates three functional modules: a variable power regulation module, a gradual shutdown control module, and a multi-level power level management module. The variable power regulation module receives power regulation commands from the operation control unit and converts them into inverter control signals for the heat pump unit to adjust the compressor's operating frequency, thereby achieving continuous adjustment of the heat pump power. The gradual shutdown control module receives the gradual shutdown trigger signal and the optimal variable power shutdown coefficient from the operation control unit and drives the source heat pump to perform gradual power shutdown according to a preset stepped decrease logic. This module integrates a stepped decrease amplitude calculation unit and a time interval control unit, with the stepped decrease amplitude set to 5% to 10% of the current power. 10. The step interval is set to 30 to 60 seconds, and the total shutdown time is controlled within the range of 3 to 10 minutes to ensure a smooth transition of the power curve. The multi-level power level management module is configured with at least three power levels for power adjustment of the steam heat pump. The high power level corresponds to 80% to 100% of the rated power, the medium power level corresponds to 40% to 60% of the rated power, and the low power level corresponds to 20% to 35% of the rated power. The switching time between each level is set to 5 to 15 seconds and a smooth transition algorithm is configured to eliminate the step impact during the power switching process. The smooth transition algorithm adopts an exponential power curve interpolation method. During the level switching process, the heat pump power gradually approaches the target value from the current value according to the exponential curve. The exponential decay time constant is set to 3 to 8 seconds to achieve smooth level switching without impact.

[0044] The steam parameter monitoring unit forms a feedback connection with the heat pump drive control unit and the operation control unit. It is configured to perform real-time monitoring of steam pressure and temperature and feed back the monitoring data to the operation control unit to support the dynamic adjustment of the control strategy. The steam parameter monitoring unit adopts a dual-channel redundant design. Each channel includes a steam pressure sensor and a steam temperature sensor. The sensors of the two channels are installed at a certain distance to eliminate the influence of local pressure fluctuations in the pipeline on the measurement. The steam parameter monitoring unit acquires steam pressure and temperature at a high-speed sampling frequency of 20 Hz. After digital filtering, the data is sent to the operation control unit in real time. The operation control unit dynamically adjusts the heat pump power output according to the feedback data to maintain the stability of steam parameters. The steam parameter monitoring unit also integrates a steam pressure over-limit alarm function. When the steam pressure is detected to exceed the upper limit of safety or fall below the lower limit of safety, it immediately sends an emergency shutdown command to the heat pump drive control unit and the system protection control unit to ensure equipment safety.

[0045] The system protection control unit forms a protective linkage with the heat pump drive control unit and the operation control unit. It is configured to monitor the transformer load status, execute cold start preheating control, and heat pump protection logic. The system protection control unit integrates three functional modules: a transformer load monitoring module, a cold start preheating control module, and a heat pump protection module. The transformer load monitoring module collects the current and voltage signals on the low-voltage side of the transformer in real time and calculates the current load rate. When the load rate exceeds 80%, it automatically sends a limiting signal to the heat pump drive control unit to limit the starting power of the source heat pump or forcibly reduce the power level. When the load rate exceeds 90%, it prohibits the source heat pump from starting to prevent grid impact. The cold start preheating control module executes compressor preheating control logic during the system's cold start phase. By adjusting the power of the compressor crankcase heating belt, it preheats the internal temperature of the compressor to the set temperature to avoid liquid slugging damage caused by liquid refrigerant entering the compressor. The preheating time is automatically calculated and determined based on the ambient temperature and the unit's downtime. The heat pump protection module monitors the number of consecutive starts and stops of the source heat pump and records the timestamp of each start and stop. When the number of consecutive starts and stops exceeds three within ten minutes, it automatically enters the heat pump protection mode. In the protection mode, the system locks the current operating status of the source heat pump and forces its minimum operating time to be extended to thirty minutes to protect the compressor from thermal stress shock caused by frequent starts and stops.

[0046] like Figure 2 As shown, the operation control method of the heat pump system for brewing includes the following steps:

[0047] Step 1: Synchronous Acquisition of Multi-Dimensional Operating Parameters and Construction of a Parameter Dataset. This step is performed by the multi-modal parameter acquisition unit. Sensor modules deployed at key nodes of the system synchronously acquire data on the steam temperature at the steam pump outlet, the hot water temperature at the steam pump inlet, the hot water temperature at the cooler outlet, the steam heat pump power, the source heat pump power, the hot water storage tank temperature, and the outdoor ambient temperature. This constructs a parameter dataset reflecting the multi-dimensional operating status of the brewing heat pump system. The specific process is as follows: The steam temperature sensor is installed at the steam heat pump outlet pipe via a threaded connection. The sensor probe penetrates one-third of the way into the pipe to accurately sense the main steam temperature. The acquired voltage signal is converted into a digital temperature value by a transmitter and transmitted to the edge computing gateway via an RS485 bus. Hot water temperature sensors are installed at three locations: the steam heat pump inlet pipe, the cooler outlet pipe, and inside the hot water storage tank. The hot water temperature sensor at the steam heat pump inlet pipe monitors the low-temperature heat source temperature entering the steam heat pump; the hot water temperature sensor at the cooler outlet pipe monitors the hot water temperature after the cooler recovers waste heat; and the hot water temperature sensor installed at the middle of the liquid level inside the hot water storage tank... Sensors are used to monitor the temperature distribution gradient of hot water in the water tank. Each hot water temperature sensor uses a thin-film platinum resistance temperature sensing element to ensure measurement accuracy and response speed. The power sensing unit collects real-time electrical power data of the steam heat pump and the source heat pump through current transformers and voltage transformers. The collected power data is conditioned by an operational amplifier circuit and then converted into digital power values ​​by an analog-to-digital converter. The ambient temperature sensor is installed in a shady outdoor location with a ventilation shield to avoid measurement errors caused by direct sunlight. The raw data collected by each sensor is uniformly transmitted to the edge computing gateway with a sampling period of one second. The edge computing gateway performs digital filtering on the raw data to eliminate power frequency interference and sensor noise, performs outlier detection to remove transient jump data, and performs timestamp alignment to ensure accurate synchronization of multi-source data in time sequence. Finally, a complete parameter dataset containing temperature parameter set, power parameter set, pressure parameter set, flow parameter set, and liquid level parameter set is generated and transmitted to the operation control unit in real time. This step completes the comprehensive perception of the multi-dimensional operating status of the brewing heat pump system, providing an absolutely deterministic data benchmark for subsequent heat demand calculation and control strategy generation.

[0048] Step 2: Calculation of heat demand-power coupling mapping and determination of operating status. This step is executed by the operation control unit. Based on the parameter dataset, it calculates the heat demand-power coupling mapping relationship and determines whether the steam heat pump can operate independently. If it is determined that it can operate independently, the source heat pump progressive shutdown control sequence is triggered. If it is determined that assistance is still needed, a variable power operation control strategy is executed. The specific process is as follows: The multi-dimensional parameter fusion processing module of the operation control unit parses the received parameter dataset, extracting the steam outlet steam temperature, steam pressure, and steam flow rate of the steam heat pump as heat demand feature input parameters. At the same time, it extracts the steam inlet hot water temperature, the cooler outlet hot water temperature, and the hot water storage tank temperature as heat source status feature input parameters. The heat demand calculation unit calculates the heat demand based on the steam temperature, pressure, and flow rate. The actual heat demand power of the current system is calculated by multiplying the steam flow rate by the change in steam enthalpy to obtain the actual heat output power. The establishment of the heat demand-power coupling mapping relationship adopts a data-driven modeling method based on Gaussian process regression. The input feature vector of the model contains six feature dimensions: steam temperature at the outlet of the steam heat pump, steam pressure, hot water temperature at the outlet of the wine cooler, hot water temperature at the inlet of the steam heat pump, hot water storage tank temperature, and outdoor ambient temperature. The output feature vector of the model contains two power values: the predicted power value of the steam heat pump and the predicted power value of the source heat pump. The root mean square error of the model's prediction is controlled within three percent of the rated power. After the model is trained with historical operating data, it can predict the power demand of the steam heat pump and the source heat pump in real time based on the current input parameters.

[0049] The control strategy generation unit reads the output of the Gaussian process regression model and executes the operation status determination logic. The core judgment basis of the determination logic is the comparison between the inlet hot water temperature of the steam heat pump and the outlet hot water temperature of the wine cooler. When the outlet hot water temperature of the wine cooler is higher than the set difference of the inlet hot water temperature of the steam heat pump and the temperature of the hot water storage tank is within the target temperature range, it is determined that the steam heat pump can currently independently utilize the waste heat of the wine cooler and the heat energy of the hot water storage tank to maintain normal operation. At this time, the source heat pump progressive shutdown control sequence is triggered to shut down the source heat pump unit. When the outlet hot water temperature of the wine cooler is insufficient to support the operation of the steam heat pump alone or the temperature of the hot water storage tank is lower than the lower limit of the target temperature, it is determined that the steam heat pump still needs the source heat pump to provide auxiliary heating. At this time, the variable power operation control strategy is executed, and the heat pump drive control unit adjusts the output power of the source heat pump to match the actual heat demand.

[0050] Step 3: The heat pump drive control unit performs progressive power shutdown control and calculates the optimal variable power shutdown coefficient. This step is executed by the heat pump drive control unit. Based on the heat demand-power coupling mapping relationship, the optimal variable power shutdown coefficient of the heat pump is calculated. Based on this coefficient, the heat pump is driven to perform progressive power shutdown, reducing the power of the heat pump in stages according to a preset step reduction until complete shutdown. The specific process is as follows: When the operation control unit determines that the steam heat pump can operate independently and triggers the progressive shutdown control sequence of the heat pump, the heat pump drive control unit... The gradual shutdown control module initiates the gradual shutdown process. First, it calculates the optimal variable power shutdown coefficient for the source heat pump at the current moment. This coefficient is calculated based on the difference between the source heat pump power demand predicted by the heat demand-power coupling mapping model and the actual operating power of the source heat pump. The coefficient value ranges from zero to one; a larger coefficient value indicates a faster shutdown speed but also a higher risk of power fluctuations. The module then executes the power shutdown operation according to a stepped decreasing control logic, using the optimal variable power shutdown coefficient as a benchmark. The decrease increment for each step is set to the current power... The first step involves reducing the source heat pump power by 5% to 10%, maintaining this power level for 30 to 60 seconds before moving to the next step to further reduce the power. This cycle continues until the source heat pump power drops below 5% of its rated power, at which point a complete shutdown is executed. The total shutdown time is calculated based on the initial power and step parameters, and is controlled within a range of three to ten minutes to ensure a smooth transition of the power curve. During each power adjustment step, the progressive shutdown control module sends a frequency adjustment signal to the source heat pump's inverter via the variable power adjustment module. The rate of change of the frequency adjustment signal is limited by the inverter's maximum acceleration / deceleration slope to ensure a smooth transition of the compressor's operating frequency. The multi-level power level management module continuously monitors the source heat pump's power level status throughout the progressive shutdown process. If the power level crosses the power level boundary, a smooth transition algorithm is automatically activated to eliminate the power level switching impact. This step achieves a smooth, gradual power reduction shutdown of the source heat pump, effectively avoiding the sudden power drop and equipment stress impact caused by immediate shutdown triggered by temperature thresholds in existing technologies.

[0051] Step four involves real-time monitoring and power fluctuation suppression control during the gradual shutdown process. This step is executed collaboratively by the operation control unit and the heat pump drive control unit. During the gradual power shutdown process, the system's total power change rate is monitored in real time. When the change rate exceeds the power fluctuation threshold, the step reduction amplitude and time interval are automatically adjusted to maintain a smooth transition of the system power curve. The specific process is as follows: The multi-dimensional parameter fusion processing module of the operation control unit continuously receives power data from the multi-modal parameter acquisition unit, calculates the sum of the steam heat pump power and the source heat pump power as the system's total power value, and simultaneously calculates the derivative of the system's total power with respect to time as the power change rate. The power change rate is calculated using the moving window difference method, with the window width set to five seconds to balance noise suppression and response speed. When the absolute value of the detected power change rate exceeds the preset power fluctuation threshold, the operation control unit sends a step parameter adjustment command to the gradual shutdown control module of the heat pump drive control unit.

[0052] The default setting for the power fluctuation threshold is 15% of the rated total power per minute. When the power change rate exceeds the upper limit of the threshold, it indicates that the current step reduction is too large, causing the system power to drop too quickly. The gradual shutdown control module automatically adjusts the reduction of the next step to 3% to 5% of the current power, and extends the step interval to 60 to 90 seconds to slow down the power drop. When the power change rate exceeds the lower limit of the threshold, it indicates that the current step reduction is too small, causing the power drop to be too slow. The gradual shutdown control module automatically adjusts the reduction of the next step to 8% to 12% of the current power, and shortens the step interval to 30 to 45 seconds to accelerate the power drop. The monitoring of the power change rate and the dynamic adjustment of the step parameters are continuously executed with a control cycle of 10 seconds until the source heat pump is completely shut down. This step ensures a smooth transition of the total system power curve during the source heat pump shutdown process, effectively eliminating the transient fluctuations in the evaporation temperature and evaporation pressure of the steam heat pump caused by the sudden drop in power, and ensuring the stability of the distillation process parameters and the reliability of the brewed liquor quality.

[0053] Step 5: Continuous monitoring of operating status and response control to sudden changes in heat demand. This step is executed collaboratively by the operation control unit, the steam parameter monitoring unit, and the heat pump drive control unit. It continuously monitors the operating status of the steam heat pump and the waste heat supply capacity of the wine cooler. When a sudden change in heat demand is detected, the start-up and shutdown requirements of the source heat pump are reassessed and corresponding control decisions are executed. The specific process is as follows: The steam parameter monitoring unit monitors the steam pressure and temperature data at the steam heat pump outlet at a sampling frequency of 20 Hz. The monitoring data is sent to the system status assessment module of the operation control unit in real time. The steam pressure prediction algorithm in the system status assessment module continuously analyzes the steam pressure time series data of the most recent 30 minutes based on a long short-term memory neural network and generates a predicted steam pressure value for the next 5 minutes. When the predicted steam pressure value shows a significant downward trend and the decrease exceeds 0.05 MPa within 5 minutes, the system status assessment module determines it as a sudden change in heat demand event and triggers the sudden change in heat demand response control process.

[0054] The heat demand mutation response control process includes two phases: reassessment and control execution. In the reassessment phase, the system status assessment module recalculates the heat demand-power coupling mapping relationship based on the current steam pressure, the outlet hot water temperature of the wine cooler, the temperature of the hot water storage tank, and the ambient temperature, and determines whether the steam heat pump can still operate independently. In the control execution phase, if it is determined that the steam heat pump cannot continue to operate independently, the variable power regulation module of the heat pump drive control unit drives the source heat pump to perform a start-up operation or a power boost operation. The start-up process uses a step-by-step incremental logic, the opposite of gradual shutdown, to increase the source heat pump power from the current power... The power is gradually increased to the target power, with the increment of each step set to 5% to 10% of the rated power and the step time interval set to 30 to 60 seconds. The multi-level power level management module is configured with a smooth transition algorithm during startup to eliminate startup shock. If it is determined that the steam heat pump can still operate independently but the heat demand is at a critical state, the multi-level power level management module of the heat pump drive control unit will switch the steam heat pump to a higher power level to enhance the heating capacity. This step realizes a preventive control response to sudden changes in heat demand, ensuring that the system can maintain a stable and reliable operating state under different operating conditions.

[0055] Example 2: This example is a variant design applied to extreme operating conditions of brewing heat pump systems and large-scale industrial brewing production lines. Compared with Example 1, this example has made adaptive adjustments to the system configuration and control strategy to meet differentiated application needs.

[0056] In extreme operating scenarios, the system is optimized for both low-temperature and high-temperature environments. In the low-temperature environment configuration, the lower limit of the ambient temperature sensor range of the multi-modal parameter acquisition unit is extended to -50 degrees Celsius to meet the environmental monitoring needs of brewing workshops in extremely cold regions during winter. The multi-level power level management module in the heat pump drive control unit adds 10% to 20% of the rated power corresponding to the ultra-low power level to meet the low-temperature start-up requirements of the heat pump unit in low-temperature environments. The upper limit of the preheating time of the cold start preheating control module in the system protection control unit is extended to 60 minutes to ensure that the compressor is fully preheated under extreme low-temperature conditions to avoid liquid slugging damage. In the high-temperature environment configuration, the upper limit of the temperature sensor range is extended to 200 degrees Celsius to meet the steam temperature monitoring needs of high-temperature workshops in summer. The heat pump drive control unit adds a power limiting protection function, which automatically reduces the heat pump power level when the compressor exhaust temperature exceeds 120 degrees Celsius to protect the compressor's safe operation. The load rate alarm threshold of the transformer load monitoring module in the system protection control unit is lowered to 75% to increase the transformer capacity margin to cope with possible power grid fluctuations in high-temperature environments.

[0057] In the context of large-scale industrial brewing production lines, the system has undergone a comprehensive performance upgrade to meet the demands of large-scale production. The operation control unit has been upgraded to a dual-machine hot standby redundant configuration, with the primary and backup controllers exchanging operational status data in real time via a high-speed synchronous bus. When the primary controller fails, the backup controller automatically takes over the control task within 50 milliseconds to ensure continuous system operation. The processing cycle of the variable power regulation module and the gradual shutdown control module of the heat pump drive control unit has been shortened from 100 milliseconds to 50 milliseconds to meet the high real-time requirements of coordinated control of more heat pump units in large-scale systems. The sampling frequency of the steam parameter monitoring unit has been increased from 20 Hz to 50 Hz to capture the more complex transient fluctuations in steam pressure in large-scale systems. The system protection control unit has added a power grid power quality monitoring module, which monitors the grid voltage deviation, frequency deviation, and harmonic content in real time. When a power quality problem is detected, corresponding protection actions are triggered.

[0058] Regarding control strategy variations, the heat demand-power coupling mapping model for large-scale scenarios adds a multi-heat pump unit collaborative optimization function. The model's output feature vector is expanded from two power values ​​to multiple power values, each corresponding to the power allocation of the steam heat pump and the source heat pump. The collaborative optimization algorithm minimizes the total system energy consumption and balances the operating time of each unit to extend the overall equipment lifespan while meeting the total heat demand. The progressive power shutdown strategy adds a multi-unit coordinated shutdown function. When multiple source heat pumps need to be shut down, the system executes the progressive shutdown of each unit in sequence according to the preset shutdown priority order. The shutdown start-up time difference between adjacent units is set to 30 to 60 seconds to avoid power superposition fluctuations caused by simultaneous shutdown. The input timing window of the steam pressure prediction algorithm is expanded from 30 minutes to 60 minutes, and the prediction time range is expanded from 5 minutes to 10 minutes to adapt to the response delay caused by the increase in thermal inertia in large-scale systems.

[0059] Comparative Example: This comparative example uses a traditional heat pump system operation control scheme to control a brewing heat pump system, in order to compare the technical effects of the progressive power shutdown and heat demand adaptive control scheme of this invention. The control system in this comparative example only uses discrete start-stop control logic based on a single temperature threshold, and does not include a multi-dimensional parameter acquisition unit, a heat demand-power coupling mapping model and a steam pressure prediction algorithm in the operation control unit, nor does it include a progressive shutdown control module and a multi-level power level management module in the heat pump drive control unit. The control strategy of the comparative example is to forcibly shut down the source heat pump when the inlet water temperature of the hot water storage tank is higher than 65 degrees Celsius, and restart the source heat pump when the inlet water temperature of the hot water storage tank is lower than 65 degrees Celsius. The start-stop of the source heat pump adopts a direct start-stop method, that is, directly jumping from zero power to rated power or directly jumping from rated power to zero power.

[0060] Regarding system energy consumption, the comparative scheme lacks a heat demand-power coupling mapping model, which prevents it from dynamically adjusting the heat pump power output according to actual heat demand. The source heat pump is forcibly shut down after auxiliary startup. At this time, the steam heat pump may still require a certain degree of auxiliary heating and is forced to maintain heat output in a high-energy-consuming self-operation mode, resulting in an increase in system energy consumption of 15% to 25%. The present invention accurately matches the heat pump power with the system heat demand through a heat demand-power coupling mapping model, and can dynamically adjust the heat pump operating power according to actual operating conditions to significantly improve energy utilization efficiency. The system energy consumption is reduced by 20% to 30% compared to the comparative scheme.

[0061] Regarding equipment lifespan, the frequent start-ups and shutdowns of the source heat pump in the comparative scheme cause accelerated fatigue aging of the compressor valve plates and seals. Actual test data shows that the compressor of the source heat pump in the comparative scheme experiences an average of more than three valve plate breakage failures within one year of operation, and the average fault-free operating time is only 4,500 hours. The present invention, through a gradual power shutdown strategy, transforms the start-up and shutdown process of the source heat pump from a step-like change to a step-like gradual change, effectively reducing the thermal stress and mechanical stress impact during the compressor start-up and shutdown process. The average fault-free operating time of the equipment is increased to more than 9,500 hours, and the service life of the equipment is extended by more than 100%.

[0062] Regarding system stability, in the comparative scheme, the total power of the system drops by 40% to 50% instantaneously after the source heat pump is forcibly shut down, causing transient fluctuations in the evaporation temperature and pressure of the steam heat pump due to the interruption of the heat source. This drives the steam output to pulsate, and the steam pressure fluctuation can reach 0.05 to 0.1 MPa. The present invention, through a gradual power shutdown strategy and real-time monitoring and suppression control of power fluctuations, controls the power change rate to within 15% of the rated total power per minute and the steam pressure fluctuation to within 0.01 MPa, effectively ensuring the stability of the distillation process parameters and the reliability of the quality of the distilled liquor.

[0063] Regarding heat pump protection, in the comparative scheme, the number of continuous start-stop cycles of the source heat pump often exceeds three or even five times within ten minutes, causing the compressor to frequently experience start-stop shocks. The comparative scheme lacks a heat pump protection module and cannot limit or protect against frequent start-stop cycles. The present invention uses a heat pump protection module in the system protection control unit to monitor the number of continuous start-stop cycles in real time. When the number of start-stop cycles exceeds three within ten minutes, it automatically enters the heat pump protection mode and forces the minimum running time to be extended to thirty minutes, effectively avoiding thermal stress damage and mechanical fatigue damage to the compressor caused by frequent start-stop cycles.

[0064] Table 1: Comparison of Embodiments and Comparative Examples of the Invention

[0065] Comparison Projects Embodiment 1 of the present invention Embodiment 2 of the present invention Comparative Example System energy consumption reduction 20% to 30% 25% to 35% Baseline energy consumption Mean Time Between Failures (MTBF) More than 9,500 hours More than 10,000 hours 4,500 hours Total power fluctuation of the system Within 15% of rated power Within 12% of rated power 40% to 50% of rated power Steam pressure fluctuation range Within 0.01 MPa Within 0.01 MPa 0.05 to 0.1 MPa Heat pump continuous start-stop protection Protection triggered more than three times within ten minutes Protection triggered more than three times within ten minutes No protection mechanism Thermal demand change response time Five-minute prediction and warning Prediction and warning within ten minutes No predictive function Total duration of gradual shutdown Three to ten minutes Three to ten minutes Turn off immediately Power level switching shock Smooth transition without impact Smooth transition without impact Step impact

[0066] The above comparison results show that the present invention, through the coordinated operation of five functional modules—a multimodal parameter acquisition unit, an operation control unit, a heat pump drive control unit, a steam parameter monitoring unit, and a system protection control unit—constructs a complete closed-loop control mechanism of heat demand perception, power coupling mapping, progressive power shutdown, power fluctuation suppression, and heat demand mutation response control. This mechanism can dynamically adjust the heat pump power output according to actual heat demand and achieve a smooth transition of the source heat pump power through a progressive power shutdown strategy. It effectively eliminates the equipment life loss caused by frequent start-stop of the heat source heat pump and the stability degradation caused by sudden drop in system power in the prior art, providing a practical and feasible technical solution for the operation control of heat pump systems used in brewing.

[0067] 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 illustrative of the 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 present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling the operation of a heat pump system used in brewing, characterized in that, Includes the following steps: S1. By synchronously collecting the steam temperature at the outlet of the steam heat pump, the hot water temperature at the inlet of the steam heat pump, the hot water temperature at the outlet of the wine cooler, the power of the steam heat pump, the power of the source heat pump, the temperature of the hot water storage tank, and the outdoor ambient temperature through the sensing modules deployed at each key node of the system, a parameter dataset reflecting the multi-dimensional operating status of the brewing heat pump system is constructed. S2. Calculate the heat demand-power coupling mapping relationship based on the parameter dataset, determine whether the steam heat pump can operate independently, if it can operate independently, trigger the source heat pump gradual shutdown control sequence, if it is determined that assistance is still needed, execute the variable power operation control strategy. S3. Calculate the optimal variable power shutdown coefficient of the source heat pump according to the heat demand-power coupling mapping relationship, and drive the source heat pump to perform a gradual power shutdown based on the optimal variable power shutdown coefficient, reducing the source heat pump power in stages according to the preset step decrease range until it is completely shut down. S4. During the gradual power shutdown process, the total power change rate of the system is monitored in real time. When the change rate exceeds the power fluctuation threshold, the step decrease amplitude and time interval are automatically adjusted to maintain a smooth transition of the system power curve. S5. Continuously monitor the operating status of the steam heat pump and the waste heat supply capacity of the wine cooler. When a sudden change in heat demand is detected, reassess the start-up and shutdown requirements of the source heat pump and execute the corresponding control decisions.

2. The operation control method for a heat pump system for brewing according to claim 1, characterized in that, In step S1, the sensing module includes an array of sensing units for collecting temperature parameters.

3. The operation control method for a heat pump system for brewing according to claim 1, characterized in that, In step S2, the establishment of the thermal demand-power coupling mapping relationship adopts a data-driven modeling method.

4. The operation control method for a heat pump system for brewing according to claim 1, characterized in that, In step S3, the gradual power shutdown strategy employs a stepped reduction control logic.

5. An operation control system for a heat pump system used in brewing, applicable to the operation control method for a heat pump system used in brewing as described in any one of claims 1-4, characterized in that, It includes a multimodal parameter acquisition unit, an operation control unit, a heat pump drive control unit, a steam parameter monitoring unit, and a system protection control unit; The multimodal parameter acquisition unit is configured to deploy sensing modules at each key node of the brewing heat pump system and electrically couple with the operation control unit through an edge computing gateway; The operation control unit is electrically connected to the multimodal parameter acquisition unit, and integrates a multidimensional parameter fusion processing module and a system status evaluation module. The heat pump drive control unit is electrically connected to the operation control unit and is configured to perform start-stop control and power regulation of the steam heat pump and the source heat pump; The steam parameter monitoring unit forms a feedback connection with the heat pump drive control unit and the operation control unit; The system protection control unit forms a protection linkage connection with the heat pump drive control unit and the operation control unit.

6. The operation control system of a heat pump system for brewing according to claim 5, characterized in that, The sensing module in the multimodal parameter acquisition unit includes a temperature sensing unit array and a power sensing unit array.

7. The operation control system of a heat pump system for brewing according to claim 5, characterized in that, The system status assessment module in the operation control unit integrates a steam pressure prediction algorithm.

8. The operation control system of a heat pump system for brewing according to claim 5, characterized in that, The heat pump drive control unit integrates a variable power adjustment module, a gradual shutdown control module, and a multi-level power level management module.

9. The operation control system of a heat pump system for brewing according to claim 5, characterized in that, The transformer load monitoring module in the system protection control unit monitors the transformer load rate in real time and performs corresponding protection control based on the load rate.

10. The operation control system of a heat pump system for brewing according to claim 9, characterized in that, The heat pump protection module in the system protection control unit monitors the number of consecutive start-stop cycles of the source heat pump and performs heat pump protection control based on the number of consecutive start-stop cycles.

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