Dual cold and heat storage system

Abstract

The application discloses a dual cold and heat storage combined supply system, and relates to the technical field of cold and heat combined supply, which comprises a variable frequency heat pump, a cold storage device, a heat storage device, a cold quantity management unit, a heat quantity management unit and a central controller. The variable frequency heat pump is suitable for multiple energy sources, has a cold side heat exchange channel and a hot side heat exchange channel which are independently arranged and connected to the cold storage device and the heat storage device respectively. The cold storage device and the heat storage device are connected to the cold quantity management unit and the heat quantity management unit through circulating pipelines respectively. The central controller is electrically connected with the variable frequency heat pump, the cold quantity management unit and the heat quantity management unit, and is internally provided with an energy storage priority control logic, which is used for controlling the start-stop and operation mode of the variable frequency heat pump according to the temperature state of the cold storage device and the heat storage device. The system can realize independent and combined energy supply, improve energy efficiency and reduce operation cost, and the energy saving performance and intelligent control are improved. The technical problems of the existing heat pump system, such as difficulty in realizing flexible cold and heat combined supply, energy waste and low overall energy efficiency, are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of combined cooling and heating, and particularly relates to a dual cold storage combined cooling and heating system. BACKGROUND

[0002] As a high-efficiency and energy-saving temperature regulation technology, the heat pump system has been widely used in building heating, hot water and industrial heating, etc. The current mainstream heat pump system mainly includes air source heat pump, water source heat pump and ground source heat pump. Among them, the air source heat pump has become the mainstream choice in residential and commercial fields due to its flexible installation, low cost, strong adaptability and other advantages. Typical applications such as variable frequency heat pump system use compressor refrigeration and heating principle to absorb heat from the environment air through finned heat exchanger, and then heat the water through the jacket heat exchanger to output hot water, realizing efficient heating and cooling, which is suitable for summer, but the hot water consumption is not large and the energy utilization is not complete. Or, in reverse, by absorbing the heat from the water source to the finned heat exchanger, air heating and warm air blowing are realized, which is suitable for winter, but at this time hot water cannot be produced and only part of the function is applicable to winter.

[0003] However, most of the existing heat pump systems only support single heating or cooling function, and cannot realize flexible switching or parallel energy supply according to the cooling and heating load demand of buildings or users. In the seasons of alternating or coexisting cooling and heating demand (such as spring and autumn seasons or multi-functional building scenes), the single-function heat pump system is difficult to match the actual demand.

[0004] In addition, in the cooling and heating conversion process, the heat pump system lacks intermediate buffering and storage of heat or cold, which causes the system to work continuously to regulate the output, reducing the coefficient of performance (COP), increasing mechanical wear and energy waste.

[0005] Therefore, some researches begin to explore the combined cooling and heating technology, that is, to integrate the cooling source and heating source output capacity in one system, and to realize the synchronous operation of refrigeration and heating through heat recovery or energy management. For example, a double-circuit heat pump system or an auxiliary heat storage unit is introduced for seasonal conversion, but there are still problems such as complex structure, difficult control, low energy storage efficiency, etc. At the same time, such systems generally cannot flexibly cut off the water source or evaporator side loop according to the actual use demand, causing the heat pump to be in a cycle of "transportation-attenuation-overconsumption" for a long time, which significantly affects the overall energy efficiency and system responsiveness.

[0006] The existing technology has the following technical problems:

[0007] (1) The traditional heat pump heating or cooling system has single function, which is difficult to meet the demand of coexisting or alternating cooling and heating;

[0008] (2) The existing combined cooling and heating technology has complex structure, lacks energy storage and regulation mechanism, and has poor cooling and heating output matching;

[0009] (3) The system lacks intelligent control and cut-off of the water source side or the evaporator side in operation, which is prone to cause energy waste;

[0010] (4) The heat pump has a significant decrease in heat / cold transport efficiency as the operation time increases, and the system has a low energy efficiency.

[0011] In summary, the prior art at least has the following technical problems:

[0012] The existing heat pump system has the technical problems of being unable to flexibly realize cold and heat supply, insufficient energy utilization, energy waste, and low overall system energy efficiency. SUMMARY

[0013] The purpose of the present application is to provide a dual cold storage and heat supply system to solve the technical problems of the existing heat pump system, such as being unable to flexibly realize cold and heat supply, insufficient energy utilization, energy waste, and low overall system energy efficiency.

[0014] The preferred technical solutions in the many technical solutions provided by the present application can produce many technical effects, which are described in detail below.

[0015] In order to solve the above technical problems, the present application provides the following technical solutions:

[0016] The present application provides a dual cold storage and heat supply system, comprising a variable frequency heat pump, a cold storage device, a heat storage device, a cold quantity management unit, a heat quantity management unit, and a central controller. The energy source of the variable frequency heat pump is a single water source or a single air source or a water source and an air source, and has independently arranged cold side heat exchange channels and hot side heat exchange channels. The cold side heat exchange channels are connected to the cold storage device, and the hot side heat exchange channels are connected to the heat storage device. The cold storage device is connected to the cold quantity management unit through a cold circulation pipeline. The heat storage device is connected to the heat quantity management unit through a hot circulation pipeline. The central controller is electrically connected to the variable frequency heat pump, the cold quantity management unit, and the heat quantity management unit, and is provided with energy storage priority control logic for controlling the start-stop and operation mode of the variable frequency heat pump based on the temperature state of the cold storage device and the heat storage device. The operation mode includes a single cold mode, a single heat mode, a cold and heat supply mode, and a standby mode.

[0017] In one embodiment, the cold side heat exchange channels and the hot side heat exchange channels both use double-sleeve composite heat exchangers. The cold side heat exchange channels transfer cold quantity to the cold storage device through the double-sleeve composite heat exchanger. The hot side heat exchange channels transfer heat to the heat storage device through the double-sleeve composite heat exchanger.

[0018] In one of the embodiments, the cold energy management unit comprises a first circulating pump, a first three-way mixing valve, a first temperature control valve and at least one cold end device; the inlet of the first circulating pump is connected to the outlet of the cold storage, and the outlet is connected to the first inlet of the first three-way mixing valve; the outlet of the first three-way mixing valve is connected to the first temperature control valve, and the first temperature control valve is connected to the cold end device; the return end of the cold end device is connected to the cold storage through the cold energy return pipeline, forming a closed cycle.

[0019] In one of the embodiments, the cold end device comprises refrigeration fins and refrigeration coils for making cold air and cold water.

[0020] In one of the embodiments, the heat energy management unit comprises a second circulating pump, a second three-way mixing valve, a second temperature control valve and at least one hot end device; the inlet of the second circulating pump is connected to the outlet of the heat storage, and the outlet is connected to the first inlet of the second three-way mixing valve; the outlet of the second three-way mixing valve is connected to the second temperature control valve, and the second temperature control valve is connected to the hot end device; the return end of the hot end device is connected to the heat storage through the heat energy return pipeline, forming a closed cycle.

[0021] In one of the embodiments, the hot end device comprises heating fins and heating coils for making warm air and hot water.

[0022] In one of the embodiments, the cold energy management unit and the heat energy management unit are respectively provided with a return temperature detection module, an electronic flow regulating valve and a bypass pipeline; wherein: the return temperature detection module is arranged on the cold energy return pipeline and the heat energy return pipeline respectively, for detecting the return temperature of the cold end device and the hot end device, and feeding back the temperature signal to the central controller; the electronic flow regulating valve is arranged on the outlet pipeline between the first temperature control valve and the cold end device, and on the outlet pipeline between the second temperature control valve and the hot end device, for adjusting the corresponding flow according to the signal of the return temperature detection module, and stably controlling the temperature of the cold end device and the temperature of the hot end device; the bypass pipeline is arranged between the second inlet of the first three-way mixing valve and the cold energy return pipeline, and between the second inlet of the second three-way mixing valve and the heat energy return pipeline, for maintaining the hydraulic balance of the system when the load is unbalanced or the end part is closed, preventing the interruption of circulation or the abnormality of pressure difference.

[0023] In one of the embodiments, the cold energy management unit further comprises a first temperature sensor; the heat energy management unit further comprises a second temperature sensor; the first temperature sensor is installed in the cold storage, and the temperature setting range of the cold storage medium is 5-10℃; the second temperature sensor is installed in the heat storage, and the temperature setting range of the heat storage medium is 25-60℃; the central controller obtains the temperature data of the cold storage and the heat storage through the first temperature sensor and the second temperature sensor respectively in real time and uses the data to determine the running state.

[0024] In one of the embodiments, the central controller is provided with three-stage timing control function, which is used to divide the running time of each day into three independent time periods, and control the running state of the variable frequency heat pump according to the preset mode priority rule in each time period; wherein: the system is set to enter the single heating mode or the cold-heat combined supply mode in the first time period, which is used to meet the demand of domestic hot water or heating; the system is set to enter the single cooling mode or the cold-heat combined supply mode in the second time period, which is used to provide the air conditioning cooling load; the system is set to enter the cold-heat combined supply mode or the energy storage priority mode in the third time period, which is used to complete the pre-charging of cold water and hot water; the first time period, the second time period and the third time period are set by the user through the central controller, and the running mode is determined by the current temperature state of the cold storage and the heat storage.

[0025] In one of the embodiments, the energy storage priority control logic of the central controller comprises: when the temperature of the cold storage is lower than the lower limit of the cold storage medium temperature setting, or the temperature of the heat storage is higher than the upper limit of the heat storage medium temperature setting, the variable frequency heat pump is controlled to stop running, and the system enters standby mode; when the temperature of the cold storage is higher than the set value of the cold storage medium temperature, and the temperature of the heat storage is in the target range, the variable frequency heat pump is controlled to only enable the cold side heat exchange path, and the system enters the single cooling mode; when the temperature of the heat storage is lower than the set value of the heat storage medium temperature, and the temperature of the cold storage is in the target range, the variable frequency heat pump is controlled to only enable the hot side heat exchange path, and the system enters the single heating mode; when the temperature of the cold storage medium is higher than the set target temperature of the cold storage medium, and the temperature of the heat storage medium is lower than the set target temperature of the heat storage medium, the variable frequency heat pump is controlled to simultaneously enable the cold side heat exchange path and the hot side heat exchange path, and the system enters the cold-heat combined supply mode; when the current power consumption time is in the valley electricity, the variable frequency heat pump is preferentially started to the energy storage medium in the cold storage and the heat storage to reach the set target temperature, and then the variable frequency heat pump is controlled to stop running, and the system enters standby mode.

[0026] The application provides a double cold and heat storage combined supply system, aiming at the problems of single function, low energy utilization efficiency and inflexible system response of existing heat pump systems, and proposes a technical scheme of structure optimization and energy saving operation strategy fusion, and has the following remarkable beneficial effects:

[0027] (1) Realize cold and heat independent channel and combined supply capacity: the application realizes flexible switching between single cold, single heat and cold and heat combined supply of the system by setting double independent configuration of cold side heat exchange channel and hot side heat exchange channel, combining the structure of cold storage and heat storage, and overcomes the functional limitation of traditional heat pump systems that cannot consider cold and heat output.

[0028] (2) Improve energy utilization efficiency and load response capacity: by setting the cold storage and heat storage, the cold and heat are stored in the off-peak period, and the energy storage is preferentially supplied in the load period, which effectively avoids the efficiency loss caused by frequent start and stop of the variable frequency heat pump, realizes efficient energy redistribution and utilization, and improves the comprehensive COP value of the system.

[0029] (3) Reduce energy waste and electricity cost: the system can combine electricity price strategy or user setting, and use valley electricity time to start the variable frequency heat pump to pre-charge the cold storage and heat storage, effectively reduce the operation electricity cost, and improve the economy of the system.

[0030] (4) Support intelligent operation control and remote adjustment: the central controller realizes automatic identification and switching of four operation modes (single cold, single heat, combined supply and standby), and makes decision and judgment combined with the energy storage temperature state, has remote control and building energy consumption management system access ability, and meets diversified control demand.

[0031] (5) Enhance system operation stability and adaptability: by setting the circulating pump, mixing valve and temperature control device of the cold quantity management unit and heat quantity management unit, the stable supply of energy storage medium temperature of cold / heat end device is guaranteed, and the bypass and flow regulating device is provided, which can cope with part load shutdown or cold and heat load fluctuation, and realizes dynamic balance operation of the system.

[0032] In summary, the application has advantages in cold and heat combined supply capacity, energy efficiency improvement, energy saving control and intelligent response, and has good industrial application prospect and popularization value in energy saving appliances and green energy saving buildings. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical scheme of the application, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0034] Figure 1is a structural schematic diagram of a double cold and heat storage combined supply system of the present application.

[0035] In the drawings, the reference signs are as follows:

[0036] 1, variable frequency heat pump; 11, cold side heat exchange passage; 12, hot side heat exchange passage; 13, double-sleeve composite heat exchanger;

[0037] 2, cold storage;

[0038] 3, heat storage;

[0039] 4, cold quantity management unit; 41, first circulating pump; 42, first three-way mixing valve; 43, first temperature control valve; 44, cold end device; 45, first temperature sensor; 46, cold quantity return pipeline;

[0040] 5, heat quantity management unit; 51, second circulating pump; 52, second three-way mixing valve; 53, second temperature control valve; 54, heat end device; 55, second temperature sensor; 56, heat quantity return pipeline;

[0041] 6, central controller;

[0042] 71, return temperature detection module; 72, electronic flow regulating valve; 73, bypass pipeline. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application.

[0044] In the specific embodiments, a double cold and heat storage combined supply system is provided, which comprises a variable frequency heat pump, a cold storage, a heat storage, a cold quantity management unit, a heat quantity management unit and a central controller; the energy source of the variable frequency heat pump is a single water source or a single air source or a water source and an air source, and the variable frequency heat pump has independently arranged cold side heat exchange passage and hot side heat exchange passage, which are connected to the cold storage and the heat storage respectively; the cold storage and the heat storage are connected to the cold quantity management unit and the heat quantity management unit through circulating pipelines respectively; the central controller is electrically connected with the variable frequency heat pump, the cold quantity management unit and the heat quantity management unit, and is internally provided with energy storage priority control logic, which is used to control the start-stop and operation mode of the variable frequency heat pump according to the temperature state of the cold storage and the heat storage; the system can realize independent and combined energy supply of cold and heat, improve energy efficiency and reduce operation cost, and the energy saving and intelligent control are improved; the technical problems that the existing heat pump system cannot flexibly realize cold and heat combined supply, and the energy utilization is insufficient, causing energy waste and low overall system energy efficiency are effectively solved.

[0045] The first embodiment of the double cold and heat storage combined supply system is as follows Figure 1As shown, including variable frequency heat pump 1, cold storage 2, heat storage 3, cold energy management unit 4, heat energy management unit 5 and central controller 6; The energy source of variable frequency heat pump 1 is single water source or single air source or water source and air source, has independently arranged cold side heat exchange passage 11 and hot side heat exchange passage 12 respectively, cold side heat exchange passage 11 is connected to cold storage 2, and hot side heat exchange passage 12 is connected to heat storage 3; Cold storage 2 is communicated with cold energy management unit 4 through cold circulation pipeline; Heat storage 3 is communicated with heat energy management unit 5 through hot circulation pipeline; Central controller 6 is electrically connected with variable frequency heat pump 1, cold energy management unit 4 and heat energy management unit 5, is provided with energy storage priority control logic, and is used for controlling the start-stop and operation mode of variable frequency heat pump 1 based on the temperature state of cold storage 2 and heat storage 3; The operation mode includes single cold mode, single heat mode, cold-heat combined supply mode and standby mode.

[0046] Wherein, when the energy source of variable frequency heat pump 1 is water source, the heat exchanger can be selected to be arranged at the underground water of deep buried ground or in the container collecting underground water, and the temperature state of water source is utilized to automatically judge the intake of cold energy or heat energy; When the energy source of variable frequency heat pump 1 is air source, the heat exchanger can be selected to be arranged at the outdoor roof or outdoor outer wall, and the temperature state of air source is utilized to automatically judge the intake of cold energy or heat energy.

[0047] The double cold-heat combined supply system of the application has the following advantages in view of the problems of single function, low energy utilization efficiency and inflexible system response of the existing heat pump system: the cold-heat independent passage and combined supply capacity are realized, the double independent configuration of cold side heat exchange passage 11 and hot side heat exchange passage 12 is arranged, the structure of cold storage 2 and heat storage 3 is combined, the flexible switching of the system between single cold, single heat and cold-heat combined supply is realized, and the functional limitation of the traditional heat pump system that cannot consider cold and heat output is overcome.

[0048] The energy utilization efficiency and load response capacity are improved, the cold and heat energy is stored in the non-load peak period by arranging cold storage 2 and heat storage 3, the energy storage priority supply is realized in the load period, the efficiency loss caused by the frequent start-stop of variable frequency heat pump 1 is effectively avoided, the efficient energy redistribution and utilization are realized, and the comprehensive COP value of the system is improved.

[0049] The energy waste and electricity cost are reduced, the system can be combined with the electricity price strategy or user setting, the variable frequency heat pump 1 is started to pre-charge cold storage 2 and heat storage 3 in the valley electricity time, the operation electricity cost is effectively reduced, and the economy of the system is improved.

[0050] The intelligent operation control and remote adjustment are supported, the automatic identification and switching of four operation modes (single cold, single heat, combined supply and standby) are realized through central controller 6, the decision judgment is made in combination with the energy storage temperature state, the remote control and building energy consumption management system access capacity are possessed, and the diversified control demand is met.

[0051] To enhance the stability and adaptability of system operation, the system is equipped with circulating pumps, mixing valves, and temperature control devices in the cooling management unit 4 and the heating management unit 5 to ensure a stable supply of energy storage medium temperature to the cold / hot end devices. It also has bypass and flow regulation devices to cope with partial load shutdown or fluctuations in cold and hot loads, and to achieve dynamic balance operation of the system.

[0052] In summary, this invention has advantages in terms of combined cooling and heating capacity, energy efficiency improvement, energy-saving control and intelligent response, and has good industrial application prospects and promotion value in energy-saving appliances and green energy-saving buildings.

[0053] As one alternative implementation method:

[0054] Regarding the specific structure of the cold-side heat exchange passage 11 and the hot-side heat exchange passage 12 that exchange energy with the cold storage tank 2 and the heat storage tank 3 respectively, this embodiment is as follows: Figure 1 As shown, both the cold-side heat exchange passage 11 and the hot-side heat exchange passage 12 adopt a double-tube composite heat exchanger 13; the cold-side heat exchange passage 11 transfers cold energy to the cold storage 2 through the double-tube composite heat exchanger 13; the hot-side heat exchange passage 12 transfers heat to the heat storage 3 through the double-tube composite heat exchanger 13.

[0055] In application, the cold-side heat exchange passage 11 and the hot-side heat exchange passage 12 exchange energy with the cold storage 2 and the heat storage 3 respectively through the double-tube composite heat exchanger 13. During the cooling or heating process, the refrigerant or heat medium flows through the inner or outer pipe section of the tube and exchanges heat with the water medium in the cold storage 2 or the heat storage 3 respectively, realizing the efficient transfer of cold or heat. This structure has the advantages of high heat exchange efficiency, clear fluid separation, and compact structure.

[0056] During application, the heat exchange efficiency can be further optimized by designing the inner and outer tube materials (such as copper and stainless steel), tube diameter ratio, and spiral winding method of the heat exchanger, making it particularly suitable for integrated equipment with limited space.

[0057] This can solve the problems of unstable heat exchange efficiency and slow response to switching between hot and cold in traditional heat pump systems, and significantly improve the efficiency of heat exchange and the speed of system thermal response.

[0058] Regarding the specific structure and connection method of the aforementioned cooling capacity management unit 4, this embodiment is, for example... Figure 1As shown, the cold energy management unit 4 includes a first circulating pump 41, a first three-way mixing valve 42, a first temperature control valve 43, and at least one cold end device 44; the inlet of the first circulating pump 41 is connected to the water outlet end of the cold storage device 2, and the outlet is connected to the first inlet of the first three-way mixing valve 42; the outlet of the first three-way mixing valve 42 is connected to the first temperature control valve 43, and the first temperature control valve 43 is connected to the cold end device 44; the backflow end of the cold end device 44 is connected to the cold storage device 2 through a cold energy backflow pipeline 46, forming a closed cycle.

[0059] The pipeline connecting the cold storage device 2 and the components of the cold energy management unit 4 is the cold cycle pipeline; the energy storage medium used in the cold storage device 2 can be water, ethylene glycol aqueous solution, salt water, or other media with high specific heat capacity.

[0060] Further, the cold end device 44 includes refrigeration fins and refrigeration coils, which are used to produce cold air and cold water for the cold end; both the refrigeration fins and the refrigeration coils can be provided in multiple numbers; the refrigeration fins can be the fins in an air conditioner, which are used to produce air conditioner cold air for a room; the refrigeration coils can be connected to a pipe-in-pipe heat exchanger to cool the water and form cold water; or the refrigeration coils can even be installed in an ice maker to provide a cold source for making ice cubes for food and drink.

[0061] In application, the cold energy management unit 4 serves as the main control path for cold water output and adjustment; the first circulating pump 41 draws the energy storage medium in the cold storage device 2, which is sequentially passed through the three-way mixing valve and the temperature control valve to enter the cold end device 44, and finally the energy storage medium is backflowed to the cold storage device 2 after being used in the end, thereby forming a closed cooling supply circuit; this structure can make the energy storage medium supplied in a constant pressure and constant quantity among various ends (such as air conditioner fin coils, refrigeration units, and cooling equipment), effectively avoiding problems such as excessive pressure difference and temperature difference fluctuation in the cold energy management unit 4 and the cold cycle pipeline; the cold energy transmission path is clear, which is conducive to dynamic temperature control and energy-saving adjustment.

[0062] In application, a bypass adjustment circuit or a partitioned flow control module can be provided to realize multi-end time-sharing control, which is conducive to meeting the demand of building multi-area cold energy load variation.

[0063] The specific structure and connection mode of the heat energy management unit 5 are as follows: Figure 1 As shown, the heat energy management unit 5 includes a second circulating pump 51, a second three-way mixing valve 52, a second temperature control valve 53, and at least one hot end device 54; the inlet of the second circulating pump 51 is connected to the water outlet end of the heat storage device 3, and the outlet is connected to the first inlet of the second three-way mixing valve 52; the outlet of the second three-way mixing valve 52 is connected to the second temperature control valve 53, and the second temperature control valve 53 is connected to the hot end device 54; the backflow end of the hot end device 54 is connected back to the heat storage device 3 through a heat backflow pipeline 56, forming a closed cycle.

[0064] The pipeline connecting the heat accumulator 3 and the components of the heat management unit 5 is a heat circulation pipeline; the energy storage medium used in the heat accumulator 3 can be water, ethylene glycol aqueous solution, salt water or other medium with high specific heat capacity.

[0065] Further, the heat terminal device 54 includes heating fins and heating coils for making hot air and hot water; the heating fins and the heating coils can be provided in multiple; the heating fins can be the fins in the air conditioner for making hot air for the room; the heating coils can be connected to the pipe-in-pipe heat exchanger to heat the water to form hot water for providing hot water for bathing or eating; or the heating coils can be installed in the floor to form floor heating for making hot air for the room.

[0066] In the application, the heat management unit 5 delivers the energy storage medium in the heat accumulator 3 to the heat terminal device 54 (such as heating fins, floor heating coils, hot water appliances, etc.) through the second circulating pump 51, adjusts the mixed temperature of the energy storage medium through the three-way mixing valve, and finally the energy storage medium returns to the heat accumulator 3 after completing the heat supply, forming a stable closed-loop heat supply path; this structure can realize constant adjustment of the temperature of the energy storage medium output from the heat accumulator 3, rapid response to the heat demand of the user, and control of the mixing ratio through the return temperature detection module 71 to adjust the heat output by the heating coils of the heat terminal device 54 to prevent the output of high-temperature energy storage medium from causing the water temperature output from the pipe-in-pipe heat exchanger to be too high to cause burns or uneven heating, especially suitable for high-comfort scenarios such as bathing and floor heating.

[0067] The temperature control and pressure balance structure of the cold management unit 4 and the heat management unit 5 to the terminal device is shown in the embodiment as Figure 1 The cold management unit 4 and the heat management unit 5 are respectively provided with a return temperature detection module 71, an electronic flow regulating valve 72 and a bypass pipeline 73.

[0068] The return temperature detection module 71 is respectively arranged on the cold return pipeline 46 and the heat return pipeline 56 for detecting the return temperature of the cold terminal device 44 and the heat terminal device 54 and feeding back the temperature signal to the central controller 6; the electronic flow regulating valve 72 is respectively arranged on the water outlet pipeline between the first temperature control valve 43 and the cold terminal device 44 and on the water outlet pipeline between the second temperature control valve 53 and the heat terminal device 54 for adjusting the corresponding flow according to the return temperature signal to stably control the temperature of the cold terminal device 44 and the temperature of the heat terminal device 54; the bypass pipeline 73 is respectively arranged between the second inlet of the first three-way mixing valve 42 and the cold return pipeline 46 and between the second inlet of the second three-way mixing valve 52 and the heat return pipeline 56 for maintaining the hydraulic balance of the system when the load is unbalanced or the terminal part is closed to prevent the circulation from being interrupted or the pressure difference from being abnormal.

[0069] In application, the backflow temperature detection module 71 cooperates with the electronic flow regulating valve to monitor the temperature of the end energy storage medium of the cold end device 44 and the hot end device 54 in real time and feed back to the central controller 6; when the end load changes or the temperature of the energy storage medium deviates from the target value, the system automatically adjusts the valve opening and the pump speed to maintain the constant supply temperature of the energy storage medium and the backflow balance; the bypass pipeline 73 is provided to ensure the stability of the circulating pressure of the energy storage medium in the pipeline when the system is running at low load or part of the cold or hot end device is closed, avoiding the phenomenon of local water hammer or circulation interruption caused by large pressure difference in the system due to the closure of the local circuit; this structure can significantly improve the stability of the energy supply system, adapt to complex and large cold or hot end use scenarios, prolong the service life of the variable frequency heat pump 1, the cold storage device 2, the heat storage device 3 and the pipe network, and is particularly suitable for large buildings with multiple cold and warm end partitions and large load differences.

[0070] The cold energy management unit 4 and the heat energy management unit 5 cooperate with the central controller 6 to control the temperature of the energy storage of the cold storage device 2 and the heat storage device 3, and the implementation example is shown in Figure 1 The first temperature sensor 45 is installed in the cold storage device 2, and the temperature of the cold storage medium of the cold storage device 2 is set to be in the range of 5-10℃; the second temperature sensor 55 is installed in the heat storage device 3, and the temperature of the heat storage medium of the heat storage device 3 is set to be in the range of 25-60℃; the central controller 6 obtains the temperature data of the cold storage device 2 and the heat storage device 3 in real time through the first temperature sensor 45 and the second temperature sensor 55 respectively and uses the temperature data to judge the running state.

[0071] In application, the first temperature sensor 45 and the second temperature sensor 55 monitor the temperature of the energy storage medium of the cold storage device 2 and the heat storage device 3 in real time, and the central controller 6 judges the current energy storage state according to the set target range (the temperature of the cold storage medium is 5-10℃, and the temperature of the heat storage medium is 25-60℃); when the set target is reached, the operation of the variable frequency heat pump 1 is automatically stopped to realize the energy storage cutoff control.

[0072] And in the valley electricity period, the central controller 6 can actively start the variable frequency heat pump 1 for refrigeration and heating, preferentially increase or decrease the temperature of the energy storage medium in the cold storage device 2 and the heat storage device 3 to the target value, fully utilize the low-price electricity to complete the energy storage, and directly call the stored cold / heat when the daytime high load to avoid frequent start and stop of the variable frequency heat pump 1.

[0073] This energy storage scheme can effectively realize the peak-shaving use of energy and the optimization of electricity cost, significantly improve the economic efficiency and intelligent energy efficiency control level of the system.

[0074] The energy storage priority control logic of the central controller 6 is specifically as follows: when the temperature of the cold storage device 2 is lower than the set lower limit of the temperature of the cold storage medium, or the temperature of the heat storage device 3 is higher than the set upper limit of the temperature of the heat storage medium, the variable frequency heat pump 1 is controlled to stop running, and the system enters a standby mode; when the temperature of the cold storage device 2 is higher than the set temperature of the cold storage medium, and the temperature of the heat storage device 3 is within the target range, the variable frequency heat pump 1 is controlled to only enable the cold side heat exchange passage 11, and the system enters a single cold mode; when the temperature of the heat storage device 3 is lower than the set temperature of the heat storage medium, and the temperature of the cold storage device 2 is within the target range, the variable frequency heat pump 1 is controlled to only enable the hot side heat exchange passage 12, and the system enters a single heat mode; when the temperature of the cold storage medium in the cold storage device 2 is higher than the set target temperature of the cold storage medium, and the temperature of the heat storage medium in the heat storage device 3 is lower than the set target temperature of the heat storage medium, the variable frequency heat pump 1 is controlled to simultaneously enable the cold side heat exchange passage 11 and the hot side heat exchange passage 12, and the system enters a cold-heat combined supply mode; when it is judged that the current power consumption time is in a valley power time, the variable frequency heat pump 1 is preferentially started to reach the set target temperature of the energy storage medium in the cold storage device 2 and the heat storage device 3, and then the variable frequency heat pump 1 is controlled to stop running, and the system enters the standby mode.

[0075] In application, the central controller 6 dynamically selects the running mode of the system according to the temperatures of the energy storage media in the cold storage device 2 and the heat storage device 3: (1) the cold storage device 2 reaches a specified low temperature, and the heat storage device 3 reaches a specified high temperature → the heat pump stops running, and the system enters a standby energy-saving state;

[0076] (2) the temperature of the cold storage device 2 is high → the cold side heat exchange passage 11 of the variable frequency heat pump 1 is started, and the system enters a single cold mode;

[0077] (3) the temperature of the heat storage device 3 is low → the hot side heat exchange passage 12 of the variable frequency heat pump 1 is started, and the system enters a single heat mode;

[0078] (4) the temperature of the cold storage device 2 is high and the temperature of the heat storage device 3 is low → the variable frequency heat pump 1 is started, and the cold side and the hot side heat exchange passages 12 are simultaneously started, and the system enters a cold-heat combined supply mode;

[0079] (5) it is judged that the current power consumption period is a valley power time → the variable frequency heat pump 1 is preferentially started to perform energy storage work of the cold storage medium and the heat storage medium even in a non-load period.

[0080] The energy storage priority control strategy combines the energy storage state and the electricity price factor, comprehensively weighs energy efficiency, response speed and running cost, realizes dynamic optimal running, adapts to multi-scene and full-period running demands, and is one of key technologies for realizing an intelligent energy efficiency building cold-heat combined supply system.

[0081] The second embodiment of the dual cold and heat storage combined supply system, which is different from the first embodiment, is that the central controller 6 is provided with a three-stage timing control function for dividing the daily operation time into three independent time periods and controlling the operation state of the variable frequency heat pump 1 according to the preset mode priority rule in each time period.

[0082] In which: the first time period is set to preferentially enter the single heat mode or the cold and heat combined supply mode to meet the demand for domestic hot water or heating; the second time period is set to preferentially enter the single cold mode or the cold and heat combined supply mode to provide the air conditioning cold load; the third time period is set to enter the cold and heat combined supply mode or the energy storage priority mode to complete the pre-charging of cold and hot water; the first time period, the second time period and the third time period are set by the user through the central controller 6 and are jointly determined by the current temperature state of the cold storage device 2 and the heat storage device 3 to determine the operation mode.

[0083] In application, the three-stage timing control function of the central controller 6 is used to divide the daily operation time of the dual cold and heat storage combined supply system into three time periods defined by the user, for example, the first time period is from 06:00 to 09:00, the second time period is from 10:00 to 17:00, and the third time period is from 18:00 to 24:00. The specific time range can be set through the touch interface of the central controller 6, the upper computer communication interface, or the wireless module connected to the background control end.

[0084] In different time periods, the dual cold and heat storage combined supply system automatically schedules the operation state according to the corresponding mode priority rule.

[0085] (1) In the first time period, the central controller 6 preferentially determines the demand for domestic hot water or heating and automatically selects the single heat mode or the cold and heat combined supply mode according to the temperature state of the heat storage device 3 to ensure the supply of hot water and heating during the morning peak period.

[0086] (2) In the second time period, the system preferentially enters the single cold mode or the cold and heat combined supply mode to provide stable cold air for office, commercial or residential spaces to meet the daytime air conditioning load demand.

[0087] (3) In the third time period, the system enters the cold and heat combined supply or energy storage priority mode to actively charge cold / heat into the cold storage device 2 and the heat storage device 3 to form a pre-energy storage preparation to support the cold and heat use during the next morning peak period.

[0088] The automatic judgment of the above mode is mainly controlled by the current time period, and is combined with the current temperature upper and lower limit state of the cold storage device 2 and the heat storage device 3 to make a joint judgment; for example, if the temperature of the cold storage medium of the cold storage device 2 reaches the target value and the temperature of the heat storage medium of the heat storage device 3 is low in the second time period, the system will switch to the single heat mode; if the cold and heat do not meet the standard in the third time period, the system will start the cold-heat heat exchange path at the same time to enter the combined supply state; between 24:00-5:00 in the early morning, the cold and heat dual energy storage is preferentially selected during the valley electricity period at night.

[0089] The three-stage timing operation strategy of the embodiment can flexibly configure the operation time and strategy according to different scenes (such as residence, office building, and hospital), and improve the response matching degree of the dual cold-heat storage combined supply system to user behavior patterns.

[0090] Through the structured management of daily operation time, the operation scheduling of the dual cold-heat storage combined supply system is more intelligent, accurate, and energy-saving; effectively solves the problem of response lag or single operation strategy of the traditional heat pump system under multiple working conditions; at the same time, optimizes the energy pre-storage strategy during the valley electricity period, reduces the operation energy consumption cost, and improves the economy; avoids cold-heat conflict or frequent start-stop of the host, improves the stability and service life of the equipment.

[0091] The technical features of the above embodiments can be combined arbitrarily, and for the sake of simplicity, not all possible combinations of the technical features in the above embodiments are described.

Claims

1. A dual cold storage and heat supply system, characterized in that, it comprises a variable frequency heat pump, a cold storage device, a heat storage device, a cold energy management unit, a heat energy management unit and a central controller; the variable frequency heat pump has a single water source or a single air source or a water source and an air source, and has a cold side heat exchange passage and a hot side heat exchange passage which are independently arranged, the cold side heat exchange passage is connected to the cold storage device, and the hot side heat exchange passage is connected to the heat storage device; the cold storage device is communicated with the cold energy management unit through a cold circulation pipeline; the heat storage device is communicated with the heat energy management unit through a heat circulation pipeline; the central controller is electrically connected with the variable frequency heat pump, the cold energy management unit and the heat energy management unit, and is provided with an energy storage priority control logic for controlling start-stop and operation mode of the variable frequency heat pump based on temperature state of the cold storage device and the heat storage device; the operation mode includes a single cold mode, a single heat mode, a cold-heat combined supply mode and a standby mode; the cold side heat exchange passage and the hot side heat exchange passage both adopt a double-sleeve composite heat exchanger; the cold side heat exchange passage performs cold energy transmission with the cold storage device through the double-sleeve composite heat exchanger; the hot side heat exchange passage performs heat energy transmission with the heat storage device through the double-sleeve composite heat exchanger; the cold energy management unit comprises a first circulating pump, a first three-way mixing valve, a first temperature control valve and at least one cold end device; the inlet of the first circulating pump is connected to the water outlet end of the cold storage device, and the outlet is connected to the first inlet of the first three-way mixing valve; the outlet of the first three-way mixing valve is connected to the first temperature control valve, and the first temperature control valve is connected to the cold end device; the return end of the cold end device is connected to the cold storage device through a cold energy return pipeline, forming a closed circulation. 2.The dual cold storage and heat supply system according to claim 1, characterized in that, the cold end device comprises refrigeration fins and refrigeration coils for producing cold air and cold water for cold end. 3.The dual cold storage and heat supply system according to claim 1, characterized in that, the heat energy management unit comprises a second circulating pump, a second three-way mixing valve, a second temperature control valve and at least one heat end device; the inlet of the second circulating pump is connected to the water outlet end of the heat storage device, and the outlet is connected to the first inlet of the second three-way mixing valve; the outlet of the second three-way mixing valve is connected to the second temperature control valve, and the second temperature control valve is connected to the heat end device; the return end of the heat end device is connected to the heat storage device through a heat energy return pipeline, forming a closed circulation. 4.The dual cold storage and heat supply system according to claim 3, characterized in that, the heat end device comprises heating fins and heating coils for producing warm air and hot water for hot end. 5.The dual cold storage and heat supply system according to claim 3, characterized in that, a return temperature detection module, an electronic flow regulating valve and a bypass pipeline are arranged in the cold energy management unit and the heat energy management unit respectively; wherein: the return temperature detection module is arranged on the cold energy return pipeline and the heat energy return pipeline respectively, for detecting return temperature of the cold end device and the heat end device, and feeding back temperature signals to the central controller. The electronic flow regulating valves are respectively arranged on the water outlet pipelines between the first temperature control valve and the cold end device and between the second temperature control valve and the hot end device, and are used for regulating corresponding flow according to signals of the backflow temperature detection module, so as to stably control the temperature of the cold end device and the temperature of the hot end device. The bypass pipelines are respectively arranged between the second inlet of the first three-way mixing valve and the cold backflow pipeline and between the second inlet of the second three-way mixing valve and the heat backflow pipeline, and are used for maintaining system hydraulic balance and preventing cycle interruption or pressure difference abnormality when the load is unbalanced or the end part is closed.

6. The dual cold and heat storage combined supply system according to claim 5, characterized in that, The cold quantity management unit further comprises a first temperature sensor, and the heat quantity management unit further comprises a second temperature sensor. The first temperature sensor is installed in the cold storage device, the temperature of the cold storage medium of the cold storage device is set to be 5-10 DEG C, the second temperature sensor is installed in the heat storage device, the temperature of the heat storage medium of the heat storage device is set to be 25-60 DEG C, and the central controller acquires temperature data of the cold storage device and the heat storage device in real time through the first temperature sensor and the second temperature sensor and is used for judging the running state.

7. The dual cold and heat storage combined supply system according to claim 6, characterized in that, The central controller is provided with three-stage timing control function, is used for dividing the running time of each day into three independent time periods, and controls the running state of the variable frequency heat pump according to preset mode priority rules in each time period. The first time period is set to be a single heat mode or a cold and heat supply mode, is used for meeting the demand of domestic hot water or heating, the second time period is set to be a single cold mode or a cold and heat supply mode, is used for providing air conditioning cold air load, and the third time period is set to be a cold and heat supply mode or an energy storage priority mode, and is used for completing the pre-energy storage of cold water and hot water. The first time period, the second time period and the third time period are set by a user through the central controller and are used for jointly judging and determining the running mode with the current temperature state of the cold storage device and the heat storage device.

8. The dual cold and heat storage combined supply system according to claim 6, characterized in that, The energy storage priority control logic of the central controller comprises: When the temperature of the cold storage device is lower than the lower limit of the set cold storage medium temperature or the temperature of the heat storage device is higher than the upper limit of the set heat storage medium temperature, the variable frequency heat pump is controlled to stop running, and the system enters standby mode; When the temperature of the cold storage device is higher than the set cold storage medium temperature and the temperature of the heat storage device is in the target range, the variable frequency heat pump is controlled to only enable the cold side heat exchange passage, and the system enters single cold mode; When the temperature of the heat storage device is lower than the set heat storage medium temperature and the temperature of the cold storage device is in the target range, the variable frequency heat pump is controlled to only enable the hot side heat exchange passage, and the system enters single heat mode. When the cold storage medium temperature of the cold storage device is higher than the set cold storage medium target temperature, and the heat storage medium temperature of the heat storage device is lower than the set heat storage medium target temperature, the variable frequency heat pump is controlled to simultaneously enable the cold side heat exchange path and the hot side heat exchange path, and the system enters a cold and heat supply mode; When it is judged that the current power consumption time is in a valley power time, the variable frequency heat pump is preferentially started to reach the set target temperature of the energy storage medium in the cold storage device and the heat storage device, and then the variable frequency heat pump is controlled to stop running, and the system enters a standby mode.

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