A multi-system cold and heat source integrated regulation and control method based on heat recovery

Abstract

This invention discloses a multi-system integrated control method for cold and heat sources based on heat recovery. The method relies on a four-tube combined cooling and heating architecture linked by a central energy management controller, a medical gas compression waste heat cascade recovery system, and a photovoltaic power generation system. This invention can achieve physical coupling of cooling of clean operating rooms and preheating of domestic hot water through a four-tube chiller unit, recovering condensation heat while outputting cooling capacity. It can also achieve energy saving and consumption reduction by uniformly scheduling photovoltaic green electricity, compression waste heat, and cooling and heating capacity through a central energy management controller.

Description

Technical Field

[0001] This invention relates to a multi-system integrated control method for cold and heat sources based on heat recovery, belonging to the field of integrated control technology for hospital cold and heat sources. Background Technology

[0002] Hospital buildings have a much higher energy density than ordinary civil buildings due to the high requirements of medical processes for temperature, humidity, cleanliness, and continuous energy supply. Their energy systems encompass multiple dimensions, including air conditioning, operating rooms, medical gases, hot water, and lighting. Due to large load differences and strong dependence on medical processes, they exhibit multi-source, discrete, and high-intensity operation characteristics.

[0003] Traditional designs follow a "demand-driven, independent operation" paradigm: air conditioning switches between heating and cooling sources seasonally, medical gases are driven by independent compressor units or oxygen stations, and hot water relies on steam, gas, or electric heating. This fragmented design historically reduced the risk of cross-system interference, but now faces the contradiction of low energy efficiency and poor operational flexibility. Specifically: Firstly, clean operating rooms require cooling year-round to maintain constant temperature and humidity, while general wards, outpatient clinics, and office areas require heating in winter, and domestic hot water is also a rigid demand. Under the current model, there is often an energy offsetting effect of "cooling on one side and heating on the other," resulting in serious waste of high-level energy.

[0004] Secondly, medical compressors generate a large amount of waste heat (exhaust temperature exceeding 100°C) when producing high-pressure gases, which is usually discharged through air or water cooling. Meanwhile, hospitals use fossil fuels or electricity to produce domestic hot water. This mismatch between energy supply and demand leads to low system thermal efficiency.

[0005] Moreover, although renewable energy sources such as photovoltaics have been introduced, they are mostly used as occasional supplementary power sources, lacking deep integration with power, heat pumps, and energy storage. The peak output of photovoltaics is mismatched with the high energy consumption of compressors and the cold storage of chillers, resulting in a low self-consumption rate of green electricity and making it difficult to realize its value in peak shaving and valley filling.

[0006] The root cause lies in the lack of a global optimization algorithm that spans air conditioning, power, water supply and drainage, and electricity. Information asymmetry exists between systems, making it impossible to uniformly schedule cooling, heating, gas, and electricity based on surgical schedules, weather forecasts, and photovoltaic fluctuations. It is necessary to break down subsystem barriers and construct an integrated control method that combines compressed waste heat recovery, cooling and heating load balancing, and multi-energy complementarity to solve key problems such as equipment redundancy, energy waste, and poor coordination. Summary of the Invention

[0007] In view of this, the purpose of this invention is to provide a multi-system integrated control method for cold and heat sources based on heat recovery, which can achieve physical coupling of cooling of clean operating rooms and preheating of domestic hot water through a four-tube chiller unit, recovering condensation heat while outputting cold energy, and can uniformly schedule photovoltaic green electricity, compressed waste heat and cold and heat energy through a central energy management controller to achieve energy saving and consumption reduction, and can overcome the shortcomings of the prior art.

[0008] The objective of this invention is achieved through the following technical solution: This invention discloses a multi-system integrated control method for cold and heat sources based on heat recovery. This method relies on a four-pipe combined cooling and heating architecture linked by a central energy management controller, a medical gas compression waste heat cascade recovery system, and a photovoltaic power generation system. It includes the following steps: Step 1: Construct a four-pipe combined cooling and heating system physical architecture: Deploy four-pipe chiller units in the hospital's energy center. Each chiller unit has an independent evaporator-side heat exchanger and a condenser-side heat exchanger that simultaneously output chilled water and hot water. The evaporator-side heat exchanger is connected to the chilled water output pipeline, providing a cooling source to the dry coil terminals in the clean operating room and the fan coil terminals in the general area. The condenser-side heat exchanger is connected to the hot water output pipeline, and through a manifold, the condensation heat generated by the cooling cycle is transported to the operating room fresh air preheating coil, the heat exchange loop of the domestic hot water storage tank, and the heating terminals to achieve local balance of cooling and heating. Step 2, establish a medical gas compression waste heat cascade recovery system: On the high-temperature exhaust manifold of the medical air compressor, a plate heat exchanger is connected through a bypass switching device; the plate heat exchanger transfers the heat of the high-temperature compressed gas discharged from the medical air compressor to the softened water in the closed heat medium water circuit, and then the high-temperature heat medium water after absorbing waste heat is transported to the heat energy utilization side through a circulation pump. Step 3, implement dynamic coupling logic on the heat energy utilization side: The central energy management controller controls the three-way proportional regulating valve set in the closed heat medium water circuit to dynamically distribute the high-temperature heat medium water to the primary heat exchange side of the domestic hot water storage tank or the fresh air preheating coil of the operating room; when the central energy management controller detects that the water temperature in the domestic hot water storage tank is lower than the preset temperature threshold, it prioritizes the heating of domestic hot water. Step 4: Execute the central integrated control logic based on multi-dimensional perception: The central energy management controller collects the output signal of the photovoltaic power generation system, the load status of the medical air compressor, the temperature and humidity parameters of the medical area, and the operating room scheduling plan in real time. Based on the objective function of maximizing the overall energy efficiency ratio of the system, it dynamically adjusts the operating frequency of the four-tube chiller, the speed of the circulating pump, and the opening degree of each branch valve.

[0009] In step 1 above, the four-tube chiller unit is equipped with operating parameters, which are: Under refrigeration conditions, the standard supply temperature of chilled water output by the evaporator-side heat exchanger is 7°C, and the return temperature is 12°C. Under heat recovery operation, the condenser heat exchanger outputs hot water with a temperature range of 45°C to 55°C according to the terminal heat load demand. The hot water output pipeline switches to the heating terminal in winter mode and prioritizes supplying the operating room fresh air preheating coil and domestic hot water storage tank in non-winter mode, thereby reducing the waste of condensing heat by reducing the opening time of the cooling tower.

[0010] As mentioned above, in step 2, a temperature sensor and a pressure sensor are installed on the high-temperature exhaust manifold. The central energy management controller dynamically adjusts the frequency of the circulation pump according to the exhaust temperature fed back by the temperature sensor, and controls the opening and closing of the bypass switching device according to the pressure fluctuation fed back by the pressure sensor, so as to ensure the stability of the outlet pressure of the medical gas.

[0011] In step 3 above, the dynamic coupling logic is as follows: the central energy management controller sets the reference temperature threshold for the domestic hot water storage tank; when the real-time water temperature Tw in the domestic hot water storage tank is less than the reference temperature threshold, the central energy management controller instructs the three-way proportional regulating valve to increase the opening of the flow channel pointing to the storage tank side, so as to preferentially inject high-quality compressed waste heat energy into the domestic hot water system; when Tw is greater than or equal to the reference temperature threshold and there is a heat demand in the operating room fresh air preheating coil, the central energy management controller adjusts the three-way proportional regulating valve to switch the excess heat medium water flow to the inlet of the operating room fresh air preheating coil, so as to realize the energy utilization according to quality tiers.

[0012] As described above, in step 4, the central energy management controller establishes a data communication network through the RS485 communication protocol and Modbus TCP gateway. The multi-dimensional sensing parameters collected include at least: the real-time output power Ppv of the photovoltaic power generation system, the operating current and load rate signal of the medical air compressor, the real-time temperature and humidity values ​​of each medical functional area, and the predicted values ​​of outdoor meteorological parameters obtained based on the meteorological prediction model. The central energy management controller, in conjunction with the operating room scheduling plan, uses the internally stored prediction algorithm to calculate the predicted value of the regional cooling and heating load demand for the next hour.

[0013] The aforementioned central energy management controller internally executes a dynamic adjustment algorithm based on an energy balance equation to establish the system's overall energy efficiency ratio. Maximizing is the objective function Its expression is: ; in: The total cooling capacity of the system includes the sum of the cooling output from the dry coil terminals and the fan coil terminals; The total heat output for system heating and fresh air preheating includes the heat output of the operating room fresh air preheating coil and the heating terminals; The heat of domestic hot water prepared through a heat recovery system; This refers to the input electrical power of the four-tube chiller unit. This refers to the input electrical power of the medical air compressor. This is the sum of the input electrical power of all circulating pump units in the system; This represents the real-time output value of the photovoltaic power generation system. The central energy management controller coordinates the compressor frequency, circulating pump speed, and opening degree of each regulating valve of the four-tube chiller unit to make the system operating state parameters converge toward the extreme point of the objective function.

[0014] The operating mode of the four-tube chiller unit described above is dynamically switched based on the heat balance criterion: When the temperature T of the domestic hot water storage tank is monitored to be less than or equal to the reference temperature threshold, and the central energy management controller calculates that the current waste heat recovery of the medical air compressor is insufficient to cover the immediate heat load gap, the central energy management controller instructs to increase the condenser side load rate of the four-tube chiller unit and increase the hot water output by increasing the condensing pressure. When the temperature T is ≥ 60℃ and the heat demand of the operating room fresh air preheating coil is zero, the controller controls the switching valve to direct the excess condensation heat generated by the four-pipe chiller unit to the cooling tower for dissipation, in order to prevent the system overpressure protection from being triggered by excessively high condensation water temperature.

[0015] The aforementioned medical gas compression waste heat cascade recovery system has a pressure interlock protection mechanism, specifically including: A proportional pressure relief valve is configured at the gas inlet of the plate heat exchanger. The central energy management controller monitors the value of the pressure sensor in real time. When the gas pressure loss caused by the heat exchanger side resistance exceeds the set threshold of 0.05MPa, the bypass switching device is automatically triggered to switch the medical gas to the original heat dissipation circuit for release. Meanwhile, the operating frequency of the circulating pump in the closed-loop heat medium water circuit The outlet exhaust temperature of the medical air compressor The following frequency converter control logic must be satisfied: Where k is the proportionality coefficient. The preset heat exchange start-up trigger temperature ensures that the optimal heat transfer temperature difference can be maintained under different compressor loads.

[0016] The aforementioned central energy management controller utilizes photovoltaic power generation systems following a "green electricity priority, energy transfer" strategy: When real-time photovoltaic output When the total power demand of the hospital's current energy system is exceeded, the central energy management controller instructs the domestic hot water system to enter overheat storage mode. In the super-temperature heat storage mode, the controller starts the auxiliary electric heating device 21 in the domestic hot water storage tank, or increases the heat pump output temperature of the four-tube chiller unit to raise the water storage temperature in the domestic hot water storage tank from the conventional 60°C to 75°C, and converts the surplus electrical energy into high-quality heat energy for storage. During periods when the photovoltaic power generation system is underpowered, the set temperature of the domestic hot water supply system is lowered to prioritize the release of sensible heat stored in the domestic hot water storage tank.

[0017] The aforementioned method also includes automatically entering a cooling and heating balance mode during the spring and autumn transition season: the central energy management controller calculates the cooling load demand of the clean operating room and the local heating demand of the general area in real time, and precisely matches the energy output ratio of the evaporation side and the condensation side by adjusting the opening of the slide valve or electronic expansion valve inside the four-pipe chiller unit, and prioritizes calling the waste heat provided by the medical gas compression waste heat cascade recovery system to make up for the heat gap. The central energy management controller integrates a fault early warning module. The module calculates the real-time scaling factor by collecting the inlet and outlet pressure difference and temperature rise rate on both sides of the plate heat exchanger. When the scaling factor exceeds the preset safety alarm limit, the central energy management controller outputs a maintenance command and switches the heat transfer medium water circuit to the standby heat exchange circuit.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention breaks the traditional pattern of independent configuration of cold and heat sources in hospitals through the in-depth application of a four-tube chiller unit. This method realizes the physical coupling of the cooling needs of clean operating rooms and the preheating needs of domestic hot water, enabling the system to effectively recover and utilize the condensation heat that would otherwise be discharged into the atmosphere while outputting cooling capacity. This greatly improves the overall energy efficiency of the system during transitional seasons. Compared with the traditional "chiller unit + boiler" model, the installed redundancy of cold and heat source equipment is reduced by about 20% to 25%, effectively saving equipment investment and machine room space.

[0019] 2. It achieves cross-domain integration of medical gas power systems and thermal energy systems. By adding a high-efficiency plate heat exchanger to the medical compressor, high-quality mechanical compression waste heat is converted into a rigid domestic hot water heat source required by the hospital. Under typical hospital operating conditions, this recovered heat can cover more than 50% of the hospital's domestic hot water demand, achieving a substantial substitution for fossil fuels or electricity, significantly reducing the hospital's operational carbon emissions, and saving no less than 15% of standard coal equivalent annually.

[0020] 3. A dynamic energy dispatch architecture based on multi-energy complementarity was constructed. This invention resolves the contradiction between the randomness of photovoltaic power generation and the stability of hospital load by using a central energy management controller to uniformly dispatch photovoltaic green electricity, compressed waste heat, and air conditioning heating and cooling. Through the "electricity-heat" conversion and transfer in the thermal energy storage link, the local consumption rate of photovoltaic power is improved, achieving dual optimization of energy utilization in both time and space dimensions.

[0021] 4. Ensures the precision of environmental control in the core medical area. This method, through the predictive control algorithm and the response speed advantage of the four-pipe system, can compensate in real time for temperature and humidity fluctuations in the operating room caused by personnel entry and exit and the start and stop of surgical equipment. While achieving energy conservation and consumption reduction, it fully meets the stringent requirements of relevant medical building technical specifications for temperature and humidity fluctuations in clean operating rooms, realizing a synergistic improvement in system operating efficiency and environmental control quality.

[0022] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will now be described in further detail with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the integrated physical architecture of the four-tube combined cooling and heating system of the present invention.

[0024] Figure 2 This is a logic block diagram of the central integrated control system of the present invention.

[0025] Figure 3 This is a schematic diagram of the medical gas compression waste heat recovery system of the present invention.

[0026] The system includes: 1. Central energy management controller; 2. Photovoltaic power generation system; 3. Four-tube chiller unit; 4. Evaporator-side heat exchanger; 5. Condenser-side heat exchanger; 6. Dry coil terminal; 7. Fan coil terminal; 8. Manifold; 9. Operating room fresh air preheating coil; 10. Domestic hot water storage tank; 11. Heating terminal; 12. Medical air compressor; 13. Plate heat exchanger; 14. Circulating pump; 15. Three-way proportional regulating valve; 16. Temperature sensor; 17. Pressure sensor; 18. RS485 communication protocol; 19. Modbus TCP gateway; 20. Proportional pressure relief valve; 21. Auxiliary electric heating device. Detailed Implementation

[0027] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0028] like Figures 1-3 As shown, this invention discloses a multi-system integrated control method for cold and heat sources based on heat recovery. This method relies on a four-pipe combined cooling and heating architecture linked to a central energy management controller 1, a medical gas compression waste heat cascade recovery system, and a photovoltaic power generation system 2. It includes the following steps: Step 1: Constructing a four-pipe combined cooling and heating system physical architecture: Deploy a four-pipe chiller unit 3 in the hospital's energy center. The four-pipe chiller unit 3 has independent evaporator-side heat exchangers 4 and condenser-side heat exchangers 5 that simultaneously output chilled and hot water. The evaporator-side heat exchanger 4 is connected to the chilled water output pipeline, providing a cooling source to the dry coil terminals 6 in the clean operating room and the fan coil terminals 7 in the general area. The condenser-side heat exchanger 5 is connected to the hot water output pipeline, and through a manifold 8, the condensation heat generated by the cooling cycle is transferred to the heat exchange loops of the operating room fresh air preheating coil 9, the domestic hot water storage tank 10, and the heating terminals 11. The system achieves local balance of heating and cooling. The four-tube chiller unit 3 has operating parameters: under cooling conditions, the standard supply temperature of chilled water output by the evaporator heat exchanger 4 is 7℃, and the return temperature is 12℃; under heat recovery conditions, the condenser heat exchanger 5 outputs hot water with a temperature range of 45℃ to 55℃ according to the terminal heat load demand; the hot water output pipeline switches to the heating terminal 11 in winter mode, and prioritizes supplying the operating room fresh air preheating coil 9 and the domestic hot water storage tank 10 in non-winter mode, thereby achieving local balance of heating and cooling within the system and significantly reducing waste heat emitted into the atmosphere through the cooling tower.

[0029] The construction of this physical architecture is primarily based on the complex and fluctuating heating and cooling load characteristics of hospital buildings. At the hardware deployment level of the hospital's energy center, a four-pipe chiller unit 3 forms the core energy conversion node. This four-pipe chiller unit 3 integrates independent evaporator-side heat exchangers 4 and condenser-side heat exchangers 5. This structural configuration allows the equipment to perform cooling and heating actions separately according to terminal commands within the same operating cycle, without being limited by the seasonal switching of traditional two-pipe systems.

[0030] Specifically, the low-temperature refrigerant generated by the evaporator-side heat exchanger 4 is transported through a chilled water output pipeline. This pipeline distributes flow after entering the core medical area. One branch connects to the dry coil terminal 6 of the clean operating room to precisely control the sensible heat load within the operating room, ensuring the operating environment remains at a constant temperature of 22°C to 25°C throughout the year. The other branch connects to the fan coil terminal 7 of the general area to meet the cooling needs of wards, outpatient departments, and other areas during the summer. Simultaneously, the condenser-side heat exchanger 5 recovers the heat absorbed in the refrigeration cycle and the heat converted from compressor power consumption into the hot water circuit, which is then transported to the manifold 8 through a hot water output pipeline. The manifold 8 then sends the hot water to the operating room fresh air preheating coil 9, the heat exchange circuit of the domestic hot water storage tank 10, and the heating terminal 11 in winter via parallel branches.

[0031] Step 2: Establish a medical gas compression waste heat cascade recovery system: A plate heat exchanger 13 is connected to the high-temperature exhaust manifold of the medical air compressor 12 via a bypass switching device. The plate heat exchanger 13 is made of 316L stainless steel with high corrosion resistance to cope with trace amounts of moisture or impurities that may be present in the medical gas. Its rated heat exchange temperature difference is designed to be no less than 10K. The plate heat exchanger 13 transfers the heat from the high-temperature compressed gas discharged from the medical air compressor 12 to the softened water in the closed heat medium water circuit. Then, the high-temperature heat medium water after absorbing waste heat is transported to the heat energy utilization side by the circulation pump 14. A temperature sensor 16 and a pressure sensor 17 are installed on the high-temperature exhaust manifold. The central energy management controller 1 dynamically adjusts the frequency of the circulation pump 14 according to the exhaust temperature fed back by the temperature sensor 16, and controls the opening and closing of the bypass switching device according to the pressure fluctuations fed back by the pressure sensor 17 to ensure the stability of the medical gas outlet pressure.

[0032] In this structure, when the medical air compressor 12 is in operation, the temperature of the high-temperature compressed gas it discharges is typically between 100°C and 120°C. This gas enters the primary side of the plate heat exchanger 13 and undergoes countercurrent heat exchange with the low-temperature softened water in the closed-loop heat transfer medium water circuit on the secondary side. The closed-loop heat transfer medium water circuit is filled with softened water that has undergone deep desalination treatment to prevent scaling during long-term operation from affecting heat exchange efficiency. The circulating pump 14 in the circuit is controlled by the central energy management controller 1, which adjusts the flow rate of the heat transfer medium water based on real-time signals from the temperature sensor 16 and pressure sensor 17 located on the high-temperature exhaust manifold. To ensure the safety of the medical gas supply, the system monitors the outlet pressure fluctuations of the compressed air in real time through the pressure sensor 17. Once the resistance of the plate heat exchanger 13 exceeds 0.05 MPa, the bypass switching device will immediately activate to ensure the continuity of gas supply and pressure stability.

[0033] Step 3, implementing dynamic coupling logic on the heat energy utilization side: The central energy management controller 1 controls the three-way proportional regulating valve 15 set in the closed heat medium water circuit to dynamically distribute high-temperature heat medium water to the primary heat exchange side of the domestic hot water storage tank 10 or the operating room fresh air preheating coil 9; when the central energy management controller 1 detects that the water temperature in the domestic hot water storage tank 10 is lower than the preset temperature threshold, it prioritizes domestic hot water heating; the dynamic coupling logic is as follows: the central energy management controller 1 sets the reference temperature threshold of the domestic hot water storage tank 10; when the real-time water temperature Tw in the domestic hot water storage tank 10 is less than the reference temperature threshold, the central energy management controller 1 instructs the three-way proportional regulating valve 15 to increase the flow channel opening towards the storage tank side, and prioritize injecting high-quality compressed waste heat energy into the domestic hot water system; when Tw is greater than or equal to the reference temperature threshold and there is heat demand in the operating room fresh air preheating coil 9, the central energy management controller 1 adjusts the three-way proportional regulating valve 15 to switch the excess heat medium water flow to the inlet of the operating room fresh air preheating coil 9, realizing energy utilization according to quality tiers.

[0034] The dynamic coupling logic on the heat energy utilization side is key to maximizing energy efficiency. After absorbing compressed waste heat, the closed-loop heat transfer medium water circuit can raise its temperature to 65°C to 85°C. This high-quality heat energy is then delivered to the heat energy regulation node. At this node, a three-way proportional regulating valve 15 proportionally distributes the high-temperature heat transfer medium water to the primary heat exchange side of the domestic hot water storage tank 10 and the operating room fresh air preheating coil 9. The central energy management controller 1 executes a priority control scheme based on feedback from the water temperature sensor in the domestic hot water storage tank 10. When the water temperature in the storage tank falls below the set threshold of 55°C, the central energy management controller 1 increases the opening of the three-way proportional regulating valve 15 to the storage tank side, rapidly raising the domestic hot water temperature using the high-quality compressed waste heat. Once the water tank reaches the required temperature, excess heat is directed to the operating room fresh air preheating coil 9 to preheat the fresh air required by the operating room (Class 10,000 or Class 100 purification). This logic achieves precise matching of heat energy in terms of quality gradient, that is, high-quality heat sources prioritize solving the domestic hot water demand, while secondary heat sources solve the air conditioning dehumidification reheating or preheating demand.

[0035] Step 4: Execute the central integrated control logic based on multi-dimensional perception: The central energy management controller 1 collects the output signal of the photovoltaic power generation system 2, the load status of the medical air compressor 12, the temperature and humidity parameters of the medical area, and the operating room scheduling plan in real time. Based on the objective function of maximizing the overall energy efficiency ratio of the system, it dynamically adjusts the operating frequency of the four-tube chiller unit 3, the speed of the circulating pump 14, and the opening degree of each branch valve. The central energy management controller 1 establishes a data communication network through the RS485 communication protocol 18 and the Modbus TCP gateway 19. The collected multi-dimensional perception parameters include at least: the real-time output power Ppv of the photovoltaic power generation system 2, the operating current and load rate signal of the medical air compressor 12, the real-time temperature and humidity values ​​of each medical functional area, and the predicted values ​​of outdoor meteorological parameters obtained based on the meteorological prediction model. The central energy management controller 1, in conjunction with the operating room scheduling plan, uses the internally stored prediction algorithm to calculate the predicted value of the regional cooling and heating load demand for the next hour.

[0036] The core of this control method lies in the multi-dimensional sensing and intelligent scheduling logic executed by the central energy management controller 1. This central energy management controller 1, acting as the system's intelligent brain, exchanges high-speed data with the photovoltaic power generation system 2, the four-tube chiller unit 3, the medical air compressor 12, and the terminal sensor network via the Modbus TCP gateway 19. The central energy management controller 1 not only monitors the current output Ppv of the photovoltaic power generation system 2 in real time, but also obtains the operating current, exhaust pressure, and real-time load rate of the medical air compressor 12 through the integrated RS485 communication protocol 18. Combining a preset operating room schedule and temperature and humidity trends obtained from the meteorological forecast interface, the central energy management controller 1 establishes a load forecasting model covering the next hour.

[0037] The central energy management controller 1 internally executes a dynamic adjustment algorithm based on the energy balance equation to establish the system's overall energy efficiency ratio. Maximizing is the objective function Its expression is: ; in: The total cooling capacity of the system includes the sum of the cooling output of the dry coil terminal 6 and the fan coil terminal 7; The total heat output for system heating and fresh air preheating includes the operating room fresh air preheating coil 9 and the heating terminal 11. The heat of domestic hot water prepared through a heat recovery system; This refers to the input electrical power of the four-tube chiller unit 3; This refers to the input electrical power of the medical air compressor 12; This is the sum of the input electrical power of all 14 circulating pumps in the system; This represents the real-time output value of photovoltaic power generation system 2; The central energy management controller 1 coordinates the compressor frequency of the four-tube chiller unit 3, the speed of the circulating pump 14, and the opening degree of each regulating valve, so that the system operating state parameters converge toward the extreme point of the objective function. That is, the central energy management controller 1, through frequency conversion regulation of the compressor frequency of the four-tube chiller unit 3, optimization of the speed of the heat recovery pump, and refined control of the opening degree of each branch electric valve, ensures that the system's operating state point always moves along the optimal energy efficiency curve while meeting the environmental indicators of each functional area of ​​the hospital.

[0038] Furthermore, the operating mode of the four-tube chiller unit 3 is dynamically switched according to the heat balance criterion: When the temperature T of the domestic hot water storage tank 10 is monitored to be less than or equal to the reference temperature threshold, and the central energy management controller 1 calculates that the current waste heat recovery of the medical air compressor 12 is insufficient to cover the immediate heat load gap, the central energy management controller 1 instructs to increase the condenser side load rate of the four-tube chiller unit 3, thereby increasing the hot water output by increasing the condensing pressure. When the temperature T ≥ 60℃ and the heat demand of the operating room fresh air preheating coil 9 is zero, the controller controls the switching valve to direct the excess condensation heat generated by the four-pipe chiller unit 3 to the cooling tower for dissipation, in order to prevent the system from overpressure protection due to excessively high condensate water temperature. Specifically, when the central energy management controller 1 monitors the temperature of the domestic hot water storage tank 10... If the temperature remains below 50℃, and the waste heat recovery calculated based on the current load rate of the medical air compressor 12 is insufficient to cover the heat load shortfall, the controller will increase the load allocation on the condenser side of the four-tube chiller unit 3. At this time, the unit will increase the condensing pressure and refrigerant flow on the condenser side to raise the temperature and power of the output hot water, thus making up for the heat shortfall. Conversely, if... If the temperature exceeds 60°C and the preheating demand for fresh air at the terminal is saturated, the controller will activate the switching valve to discharge excess condensation heat to the atmosphere through the cooling tower, in order to prevent the unit from tripping due to excessively high condensation water temperature and ensure the safe and stable operation of the system.

[0039] The medical gas compression waste heat cascade recovery system has a pressure interlock protection mechanism, specifically including: A proportional pressure relief valve 20 is configured at the gas inlet of the plate heat exchanger 13. The central energy management controller 1 monitors the value of the pressure sensor 17 in real time. When the gas pressure loss caused by the heat exchanger side resistance exceeds the set threshold of 0.05MPa, the bypass switching device is automatically triggered to switch the medical gas to the original heat dissipation circuit for release. Meanwhile, the operating frequency of the closed-loop heat medium water circulation pump 14 The outlet exhaust temperature of medical air compressor 12 The following frequency converter control logic must be satisfied: Where k is the proportionality coefficient. The preset heat exchange start-up trigger temperature ensures that the optimal heat transfer temperature difference is maintained under different compressor loads. This frequency conversion logic ensures that the heat exchanger always maintains the best heat transfer temperature difference under different compressor loads, avoiding ineffective power loss of the water pump.

[0040] The utilization of photovoltaic power generation system 2 by the central energy management controller 1 follows the strategy of "green electricity priority and energy transfer": When real-time photovoltaic output When the total power demand of the hospital's current energy system is exceeded, the central energy management controller 1 instructs the domestic hot water system to enter the overheat storage mode; In the overheating heat storage mode, the controller activates the auxiliary electric heating device 21 in the domestic hot water storage tank 10, or increases the heat pump output temperature of the four-pipe chiller unit 3, raising the water temperature in the domestic hot water storage tank 10 from the conventional 60°C to 75°C, converting surplus electrical energy into high-quality heat energy for storage; during periods when the output of the photovoltaic power generation system 2 is insufficient, the set temperature of the domestic hot water supply system is lowered to prioritize the release of sensible heat stored in the domestic hot water storage tank 10.

[0041] This operation essentially stores excess instantaneous electrical energy as sensible heat in a large hot water storage tank. When the photovoltaic system stops outputting power at night or during peak electricity consumption periods, the controller releases the stored heat preferentially by reducing the water supply setpoint of the storage tank. This achieves optimized energy allocation across time periods without increasing external energy input.

[0042] This method also includes automatically entering a cooling and heating balance mode during the spring and autumn transition seasons: the central energy management controller 1 calculates in real time the cooling load demand of the clean operating room and the local heating demand of the general area. By adjusting the opening of the sliding valve or electronic expansion valve inside the four-tube chiller unit 3, it precisely matches the energy output ratio of the evaporation side and the condensation side, and prioritizes the use of waste heat provided by the medical gas compression waste heat cascade recovery system to make up for the heat gap. In this mode, the central energy management controller 1 calculates in real time the cooling and dehumidification load of the clean operating room and the possible local heating load of the ward area. The controller dynamically balances the energy output of the evaporation side and the condensation side by adjusting the sliding valve or electronic expansion valve inside the four-tube chiller unit 3. When the total cooling demand of the system is slightly greater than the heating demand, a small amount of waste heat is discharged by fine-tuning the frequency of the cooling tower's heat dissipation fan; when the total heating demand is large, the waste heat of the medical air compressor 12 is used in conjunction. Through this precise dynamic matching, the energy offsetting waste phenomenon of "cooling on one side and heating on the other" common in traditional buildings is eliminated to the greatest extent.

[0043] The central energy management controller 1 integrates a fault early warning module. This module calculates the real-time scaling factor by collecting the inlet and outlet pressure difference and temperature rise rate on both sides of the plate heat exchanger 13. When the scaling factor exceeds the preset safety alarm limit, the central energy management controller 1 outputs a maintenance command and switches the heat transfer medium water circuit to the standby heat exchange circuit. The fault early warning module enables long-term health management of the system's core components. This module collects the inlet and outlet pressure difference between the primary and secondary sides of the plate heat exchanger 13 in real time, combines this with flow data provided by the flow meter, uses heat transfer formulas to calculate the heat transfer coefficient in real time, and further calculates the scaling factor. When the scaling factor reaches the preset yellow warning threshold, the system automatically pushes a cleaning and maintenance command on the human-machine interface and suggests that operators switch to the standby heat exchange circuit during low-load periods. This predictive maintenance mechanism effectively avoids a decrease in the system's overall COP due to heat exchange efficiency degradation.

[0044] To further verify the technical effectiveness of the integrated control method for multiple cold and heat sources in a hospital based on heat recovery provided by this invention, a detailed quantitative demonstration is presented below with reference to specific embodiments and comparative examples.

[0045] Example 1 uses the outpatient building and surgical center of a tertiary-level Class A hospital as an example. The building has a total area of ​​65,000 square meters and 20 clean operating rooms. The system is equipped with a single 2100kW four-tube chiller unit and a 120kWp rooftop photovoltaic system. The total power of the medical air compressor unit is 110kW. Using the integrated control method described in this invention, a central energy management controller is set up to integrate and schedule the four energy flows: cooling, heating, electricity, and gas.

[0046] On a typical summer operating day (average daily temperature 32°C), the four-pipe unit provides 7°C chilled water while recovering condensation heat to produce 50°C hot water. The medical air compressor exhaust temperature is maintained at 105°C, and the average power of the heat recovered through the plate heat exchanger reaches 65kW. The photovoltaic system provides approximately 90kW of power support between 10:00 and 14:00, with excess power triggering the water storage tank to "overheat and store heat" up to 72°C.

[0047] Comparative Example 1: The hospital employs a traditional energy solution. This involves using conventional screw chillers for cooling, with the heat from condensation being entirely released into the atmosphere via a cooling tower. Domestic hot water is supplied independently by a gas-fired boiler. Waste heat from the medical air compressor is directly discharged into the machine room environment through its integrated air-cooled radiator and then exhausted by an exhaust fan. The electricity generated by the photovoltaic system follows a simple "self-consumption, surplus power to the grid" model and is not integrated with the heating / cooling system.

[0048] Under the same external environment and end-user demand conditions, the comparison results of the operating data of Example 1 and Comparative Example 1 were obtained through continuous monitoring for a year, as shown in Table 1.

[0049] Table 1: Comparison of the operational performance of the embodiments of the present invention and traditional solutions ; Analysis of the data in Table 1 shows that Example 1 achieved a significant leap in overall energy efficiency ratio (SCOP), reaching 6.85. This is mainly attributed to the direct offsetting of heating and cooling loads by the four-pipe unit and the cascaded utilization of waste heat from the medical compressor. Regarding operating costs, by reducing the use of gas-fired boilers and increasing the utilization rate of photovoltaic green electricity, annual operating costs were reduced by 28.88%. Most importantly, while improving system efficiency, the method of this invention significantly enhances the stability of operating room environmental control through predictive control logic, reducing the time spent exceeding temperature and humidity limits by more than 90%.

[0050] Furthermore, a detailed analysis was conducted on the specific operating conditions during the transitional season. During operation in April, the four-pipe system of Example 1 accurately matched the dehumidification and reheat requirements of the operating room. Specifically, when the operating room required an air environment of 22°C and 50% humidity, the system first used 7°C chilled water for cooling and dehumidification, and then used recovered 45°C hot water for reheat compensation. Since the cold and heat sources were provided by the same main unit, the system response time was shortened to the second level, avoiding temperature fluctuations caused by the start-up delay of the gas boiler in traditional solutions. At this time, the system's instantaneous COP could reach over 8.0. In contrast, Comparative Example 1 required the simultaneous operation of the chiller and gas boiler during this period, resulting in significant energy offsetting, and its real-time COP was only around 1.8.

[0051] In the medical gas compression waste heat recovery process, Embodiment 1 of this invention demonstrates extremely high stability. Experimental data shows that after 2000 hours of continuous operation, the scaling factor monitored by the fault warning module increased by only 5%, far below the alarm limit, proving the scientific validity of the closed-loop softened water circuit design. Simultaneously, due to the recovery of compression waste heat, the ambient temperature of the medical air compressor room decreased from 45℃ to 28℃, significantly reducing the energy consumption of the room's ventilation system and extending the service life of the compressor's electronic components.

[0052] Regarding photovoltaic (PV) power consumption, Example 1 successfully absorbed almost all redundant PV power during the midday period through an "overheated thermal storage" logic. Table 1 shows that its absorption rate reached as high as 98.5%, meaning that the hospital hardly needs to sell electricity to the grid at low prices, but instead converts it into high-value thermal energy reserves. This "electricity-heat" energy transfer technology played a significant role during the peak period of domestic hot water supply in the summer afternoons, reducing the peak load on the power grid by approximately 45kW.

[0053] In summary, the integrated control method for multiple cold and heat sources in a hospital based on heat recovery, as described in this invention, achieves profound technological innovation in both physical architecture and control logic through the organic integration of a four-tube chiller unit 1, a medical compressor waste heat recovery system, and a photovoltaic power generation system 25, coupled with precise core algorithm scheduling. This invention not only significantly reduces the overall energy efficiency of hospitals—a special type of public building—achieving substantial energy conservation and emission reduction, but also ensures the safety and comfort of the medical environment through multi-energy complementarity and redundancy design. The method is logically rigorous and has detailed parameters, possessing high engineering application value and providing solid technical support for the construction of modern green and smart hospitals.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments without departing from the technical solution of the present invention and based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A multi-system cold and heat source integrated regulation and control method based on heat recovery, characterized in that, This method relies on a four-pipe combined cooling and heating architecture linked by a central energy management controller (1), a medical gas compression waste heat cascade recovery system, and a photovoltaic power generation system (2), and includes the following steps: Step 1, constructing a four-pipe combined cooling and heating physical architecture: deploy a four-pipe chiller unit (3) in the hospital energy center, utilizing the independent evaporator-side heat exchanger (4) and condenser-side heat exchanger (5) inside the four-pipe chiller unit (3) to synchronously output chilled water and hot water; the evaporator-side heat exchanger (4) is connected to the chilled water output pipeline, providing a cold source to the dry coil end (6) of the clean operating room and the fan coil end (7) of the general area respectively; the condenser-side heat exchanger (5) is connected to the hot water output pipeline, and through the manifold (8) the condensation heat generated by the cooling cycle is transported to the heat exchange loop of the fresh air preheating coil (9) of the operating room, the domestic hot water storage tank (10) and the heating terminal (11) to achieve local balance of cooling and heating; Step 2, establish a medical gas compression waste heat cascade recovery system: connect a plate heat exchanger (13) to the high temperature exhaust manifold of the medical air compressor (12) through a bypass switching device; the plate heat exchanger (13) transfers the heat of the high temperature compressed gas discharged from the medical air compressor (12) to the softened water in the closed heat medium water circuit, and then the high temperature heat medium water after absorbing waste heat is transported to the heat energy utilization side through the circulation pump (14); Step 3, realize the dynamic coupling logic of the heat energy utilization side: The central energy management controller (1) controls the three-way proportional regulating valve (15) set in the closed heat medium water circuit to dynamically distribute the high temperature heat medium water to the primary heat exchange side of the domestic hot water storage tank (10) or the fresh air preheating coil (9) of the operating room; when the central energy management controller (1) detects that the water temperature in the domestic hot water storage tank (10) is lower than the preset temperature threshold, it prioritizes the heating of domestic hot water; Step 4, execute the central integrated control logic based on multi-dimensional perception: The central energy management controller (1) collects the output signal of the photovoltaic power generation system (2), the load status of the medical air compressor (12), the temperature and humidity parameters of the medical area and the operating room scheduling plan in real time, and dynamically adjusts the operating frequency of the four-tube chiller unit (3), the speed of the circulating pump (14) and the opening degree of each branch valve based on the objective function of maximizing the overall energy efficiency ratio of the system.

2. The multi-system cold and heat source integrated regulation and control method based on heat recovery according to claim 1, characterized in that, In step 1, the four-tube chiller unit (3) is provided with operating parameters, which are: Under refrigeration conditions, the standard supply temperature of chilled water output by the evaporator-side heat exchanger (4) is 7°C, and the return temperature is 12°C. Under heat recovery conditions, the condenser heat exchanger (5) outputs hot water with a temperature range of 45°C to 55°C according to the terminal heat load demand. The hot water output pipeline switches to the heating terminal (11) in winter mode and prioritizes supplying the operating room fresh air preheating coil (9) and domestic hot water storage tank (10) in non-winter mode, thereby reducing the waste of condensing heat by reducing the opening time of the cooling tower. 3.The method of claim 1, wherein, In step 2, a temperature sensor (16) and a pressure sensor (17) are installed on the high-temperature exhaust manifold. The central energy management controller (1) dynamically adjusts the frequency of the circulating pump (14) according to the exhaust temperature fed back by the temperature sensor (16), and controls the opening and closing of the bypass switching device according to the pressure fluctuation fed back by the pressure sensor (17) to ensure that the outlet pressure of the medical gas is stable. 4.The method of claim 1, wherein, In step 3, the dynamic coupling logic is as follows: the central energy management controller (1) sets the reference temperature threshold of the domestic hot water storage tank (10); when the real-time water temperature Tw in the domestic hot water storage tank (10) is less than the reference temperature threshold, the central energy management controller (1) instructs the three-way proportional regulating valve (15) to increase the opening of the flow channel pointing to the storage tank side, and preferentially inject high-quality compressed waste heat energy into the domestic hot water system; when Tw is greater than or equal to the reference temperature threshold and there is a heat demand in the operating room fresh air preheating coil (9), the central energy management controller (1) adjusts the three-way proportional regulating valve (15) to switch the excess heat medium water flow to the inlet of the operating room fresh air preheating coil (9), so as to realize the energy utilization according to the quality tier.

5. The multi-system cold and heat source integrated regulation and control method based on heat recovery according to claim 1, characterized in that, In step 4, the central energy management controller (1) establishes a data communication network through RS485 communication protocol (18) and Modbus TCP gateway (19). The multi-dimensional sensing parameters collected include at least: the real-time output power Ppv of the photovoltaic power generation system (2), the operating current and load rate signal of the medical air compressor (12), the real-time temperature and humidity values ​​of each medical functional area, and the outdoor meteorological parameter prediction values ​​obtained based on the meteorological prediction model. The central energy management controller (1) combines the operating room scheduling plan and uses the internally stored prediction algorithm to calculate the predicted value of regional cooling and heating load demand in the next hour.

6. The multi-system cold and heat source integrated control method based on heat recovery according to claim 1, characterized in that, The central energy management controller (1) internally executes a dynamic adjustment algorithm based on the energy balance equation to establish the system's overall energy efficiency ratio. Maximizing is the objective function Its expression is: ； in: The total cooling capacity of the system includes the sum of the cooling output of the dry coil terminal (6) and the fan coil terminal (7); The total heat output of the operating room fresh air preheating coil (9) and the heating terminal (11) is used for system heating and fresh air preheating. The heat of domestic hot water prepared through a heat recovery system; The input electrical power of the four-tube chiller unit (3); The input electrical power of the medical air compressor (12); It is the sum of the input electrical power of all circulating pumps (14) in the system; The real-time output value of the photovoltaic power generation system (2); The central energy management controller (1) coordinates the compressor frequency of the four-tube chiller unit (3), the speed of the circulating pump (14), and the opening degree of each regulating valve, so that the system operating state parameters converge to the extreme point of the objective function.

7. The multi-system cold and heat source integrated control method based on heat recovery according to claim 1, characterized in that, The operating mode of the four-tube chiller unit (3) is dynamically switched according to the heat balance criterion: When the temperature T of the domestic hot water storage tank (10) is monitored to be less than or equal to the reference temperature threshold, and the central energy management controller (1) calculates that the current waste heat recovery of the medical air compressor (12) is insufficient to cover the immediate heat load gap, the central energy management controller (1) instructs to increase the condensing side load rate of the four-tube chiller unit (3) and increase the hot water output by increasing the condensing pressure. When the temperature T is monitored to be ≥ 60°C and the heat demand of the operating room fresh air preheating coil (9) is zero, the controller controls the switching valve to direct the excess condensation heat generated by the four-pipe chiller unit (3) to the cooling tower for dissipation, so as to prevent the system overpressure protection from being triggered by excessively high condensation water temperature.

8. The multi-system integrated control method for heat recovery based on heat source according to claim 1, characterized in that, The medical gas compression waste heat cascade recovery system has a pressure interlock protection mechanism, specifically including: A proportional pressure relief valve (20) is configured at the gas inlet of the plate heat exchanger (13). The central energy management controller (1) monitors the value of the pressure sensor (17) in real time. When the gas pressure loss caused by the heat exchanger side resistance exceeds the set threshold of 0.05MPa, the bypass switching device is automatically triggered to switch the medical gas to the original heat dissipation circuit for release. Meanwhile, the operating frequency of the circulating pump (14) in the closed-loop heat medium water circuit The outlet exhaust temperature of the medical air compressor (12) The following frequency converter control logic must be satisfied: Where k is the proportionality coefficient. The preset heat exchange start-up trigger temperature ensures that the optimal heat transfer temperature difference can be maintained under different compressor loads.

9. The multi-system integrated control method for heat recovery based on heat source according to claim 1, characterized in that, The central energy management controller (1) utilizes the photovoltaic power generation system (2) in accordance with the strategy of "green electricity priority and energy transfer": When real-time photovoltaic output When the total power demand of the current hospital energy system is exceeded, the central energy management controller (1) instructs the domestic hot water system to enter the overheat storage mode; In the super-temperature heat storage mode, the controller starts the auxiliary electric heating device (21) in the domestic hot water storage tank (10), or increases the heat pump output temperature of the four-pipe chiller unit (3) to raise the water storage temperature in the domestic hot water storage tank (10) from the conventional 60°C to 75°C, and converts the surplus electrical energy into high-quality heat energy for storage. During periods when the output of the photovoltaic power generation system (2) is insufficient, the sensible heat stored in the domestic hot water storage tank (10) is released preferentially by lowering the set temperature of the domestic hot water supply system.

10. The multi-system cold and heat source integrated control method based on heat recovery according to claim 1, characterized in that, The method also includes automatically entering the heat balance mode during the spring and autumn transition season: the central energy management controller (1) calculates the cooling load demand of the clean operating room and the local heating demand of the ordinary area in real time, and precisely matches the energy output ratio of the evaporation side and the condensation side by adjusting the sliding valve opening or electronic expansion valve inside the four-pipe chiller unit (3), and prioritizes calling the waste heat provided by the medical gas compression waste heat cascade recovery system to make up for the heat gap. The central energy management controller (1) integrates a fault early warning module. The module calculates the real-time scaling factor by collecting the inlet and outlet pressure difference and temperature rise rate on both sides of the plate heat exchanger (13) in real time. When the scaling factor exceeds the preset safety alarm limit, the central energy management controller (1) outputs a maintenance command and switches the heat medium water circuit to the standby heat exchange circuit.

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