Electric heating energy storage system

Abstract

The utility model relates to the technical field of electric heating energy storage, and discloses an electric heating energy storage system which comprises a heat preservation shell, a plurality of heat storage modules, a heat exchanger, an air inlet pipeline, an air outlet pipeline, an electric heating element and a fan. When the electric heating energy storage system operates, the heat release quantity of the heat storage module can be separately controlled according to the fluctuation of the heat load of a user; when one or some heat storage modules break down, other normal heat storage modules can work normally to supply heat; and meanwhile, the heat exchange temperature difference at the inlet of each heat storage chamber can be effectively reduced, and the temperature difference at the outlet of the heat exchange chamber is reduced, so that the problems of thermal stress and large thermal displacement caused by large temperature difference at the inlet and the outlet are solved. The flow of heat exchange air is adjusted by adjusting the number of the heat storage modules for releasing heat and adjusting the opening degree of the air inlet valve or the working frequency of the draught fan, so that two-stage adjustment of the heat supply amount is achieved, and the adjustment range of the heat supply amount can be effectively widened.

Description

Technical Field

[0001] The utility model relates to the technical field of electric thermal energy storage, in particular to an electric thermal energy storage system. Background Art

[0002] Electric thermal energy storage technology uses electric heating to convert green electricity (valley electricity) into thermal energy and stores it in a thermal storage module. When in use, the heat is then taken from the high-temperature heat storage body using a heat exchange fluid to provide hot water, process steam, etc. to the outside world. It has the advantages of low heat storage cost and reliable operation. Electric thermal energy storage technology has now begun to be applied to clean heating, heat storage peak regulation, industrial heating and other fields.

[0003] At present, the existing electric thermal energy storage system only has one single heat storage module arranged inside it. When the heating load is large and the single heat storage module fails, it needs to be shut down for maintenance. At this time, the single heat storage system will not be able to supply heat to the outside world. In addition, in large-capacity electric thermal energy storage systems, the heat storage module and the heat exchange air at the inlet section of the single heat storage module have a large temperature difference and a large temperature change. The arrangement of a large number of heat storage units in the inlet section area is prone to cause large thermal stress and thermal displacement, which has a great impact on the service life of the inlet section heat storage module and the heat exchange performance of the system. At the same time, during the operation of the electric thermal energy storage system, the solid-state electric heat storage device usually adjusts the frequency of the fan or the opening of the air valve to control the heat extraction power in the heat release stage when releasing heat. For the case where the user's heat load fluctuates greatly, the fan frequency adjustment range is narrow, and the pressure energy loss caused by valve adjustment is large, which is not conducive to the efficient operation of the electric thermal energy storage system. Utility Model Content

[0004] In view of this, the utility model provides an electric thermal energy storage system to solve the problems of the existing electric thermal energy storage system being unable to provide heat when shut down for maintenance, the life of the inlet section heat storage module being affected, and the narrow heat extraction power adjustment range.

[0005] In a first aspect, the utility model provides an electric thermal energy storage system, comprising:

[0006] A heat-insulating shell having a plurality of heat storage chambers therein, each of the heat storage chambers being provided with an inlet and an outlet;

[0007] A plurality of heat storage modules are arranged in the heat storage chamber in a one-to-one correspondence;

[0008] A heat exchanger is arranged outside the heat-insulating shell;

[0009] An air inlet duct, the two ends of which are respectively connected to the air outlet of the heat exchanger and the inlet of each heat storage chamber; an air inlet valve is provided on the air inlet path of each inlet;

[0010] An air outlet duct, both ends of which are connected to the outlet of each heat storage chamber and the air inlet of the heat exchanger; an air outlet valve is provided on the air outlet path of each outlet;

[0011] An electric heating element is disposed inside each of the heat storage modules; the electric heating element is suitable for being electrically connected to a power source;

[0012] The fan is arranged on the air inlet duct.

[0013] Beneficial effects: The electric thermal energy storage system of this structure is achieved by arranging multiple heat storage modules in a plurality of heat storage chambers in a one-to-one correspondence, and each heat storage chamber is provided with an inlet and an outlet, the two sides of the air inlet duct are connected to the air outlet of the heat exchanger and the inlet of the heat storage chamber, and the air outlet duct is connected to the outlet of the heat storage chamber and the air inlet of the heat exchanger to form an air circulation system. An air inlet valve is provided on the air inlet path of each inlet, and an air outlet valve is provided on the air outlet path of each outlet, so that the air inlet and air outlet of each heat storage chamber can be controlled separately. When the electric thermal energy storage system is in operation, when the user's heat consumption is large, the number of heat storage modules for heat release can be increased, and when the user's heat consumption is reduced, the number of heat storage modules for heat release can be reduced, so as to realize the separate control of the heat release quantity of the heat storage modules according to the fluctuation size of the user's heat load; when one or some heat storage modules fail, other normal heat storage modules can work normally to provide heat; at the same time, multiple heat storage modules are placed in different heat storage chambers, low-temperature heat exchange air enters the heat storage chamber through the inlet, and the high-temperature gas after heat exchange flows out to the heat exchanger through the outlet. The low-temperature heat exchange air enters through the respective inlet of each heat storage chamber and flows out from the respective outlet of each heat storage chamber. Compared with the method of entering the insulation shell from the same total air inlet and flowing out of the insulation shell from the same total air outlet, the heat exchange temperature difference at the inlet of each heat storage chamber can be effectively reduced, and the temperature difference at the outlet of the heat exchange chamber can be reduced, thereby reducing the thermal stress and large thermal displacement caused by the large temperature difference at the inlet and outlet, and preventing the heat storage module from shifting and tipping, thereby ensuring the stability of the overall structure of the heat storage module. By adjusting the number of heat storage modules for heat release, and adjusting the opening of the air inlet valve or the operating frequency of the fan to adjust the flow of heat exchange air, two-stage regulation of the heat supply can be achieved, which can effectively increase the adjustment range of the heat supply, facilitate the adjustment of the heat supply according to the user's heat consumption, match the heat supply with the heat consumption, and facilitate the efficient operation of the electric thermal energy storage system; at the same time, by setting up multiple heat storage chambers, the heat exchange air enters different heat storage chambers through the air inlet duct, and the hot air after heat exchange flows out from different heat storage chambers to the air outlet duct. Compared with the method of setting up a large-capacity single heat storage module, the operating wind resistance can be reduced and the cost of system operation can be reduced. In addition, compared with the structure of setting up a single large-capacity heat storage module, setting up multiple heat storage modules changes the single inlet and single outlet to a multi-inlet and multi-outlet structure, and the space of a single heat storage chamber is reduced, which is conducive to the uniformity of the smooth distribution of air in the heat storage chamber, so that the air and the heat storage module can fully and effectively exchange heat to improve the heat exchange efficiency.

[0014] In an optional embodiment, the air inlet duct includes an air inlet main pipe and multiple air inlet branch pipes, and the air outlet duct includes an air outlet main pipe and multiple air outlet branch pipes; one side of the air inlet main pipe is connected to the air outlet of the heat exchanger, and the air inlet main pipe is connected in parallel with all the inlets through multiple air inlet branch pipes; one side of the air outlet main pipe is connected to the air inlet of the heat exchanger, and the air outlet main pipe is connected in parallel with all the outlets through multiple air outlet branch pipes; the fan is arranged on the air inlet main pipe.

[0015] Beneficial effects: The parallel connection method can simplify the system structure and save equipment costs.

[0016] In an optional embodiment, the air inlet valve is arranged on the air inlet branch pipe, and the air outlet valve is arranged on the air outlet branch pipe.

[0017] In an optional embodiment, adjacent heat storage chambers are separated by heat insulation members.

[0018] Beneficial effects: The thermal insulation separates different heat storage modules, which can store or release heat independently. Different heat storage modules do not affect each other, and the output power of the electric thermal energy storage system can be adjusted by adjusting the amount of heat released by the heat storage modules. At the same time, during the heat release period, by adjusting the amount of heat released by the heat storage modules and the flow rate of the heat exchange medium flowing through different heat storage modules, two-stage regulation is adopted to achieve flexible adjustment of the output power to match the large fluctuations in the user's heat load.

[0019] In an optional embodiment, each of the heat storage modules is spaced apart from the thermal insulation element.

[0020] In an optional embodiment, each of the heat storage modules is provided with a placement hole and a circulation hole, the electric heating element is arranged in the placement hole, and the circulation hole is used for heat exchange air to circulate.

[0021] In an optional embodiment, each of the heat storage modules is provided with multiple layers of placement holes and multiple layers of circulation holes, and the placement holes and the circulation holes are spatially orthogonal.

[0022] In an optional embodiment, the placement holes at the same height of all the heat storage modules extend in the same direction along the same channel, and the electric heating elements are arranged through the placement holes at the same height of all the heat storage modules.

[0023] In an optional embodiment, each of the heat storage modules includes a plurality of heat storage units, the heat storage units are in the shape of a rectangular block, the placement hole and the flow hole are provided inside the heat storage unit; a groove is provided on the outer wall surface of the heat storage unit, and a plurality of the heat storage units are stacked, and the grooves on adjacent outer wall surfaces of adjacent heat storage units are connected to form the flow hole located outside the heat storage unit.

[0024] In an optional embodiment, it also includes a control cabinet, a power cord and an insulating member; the insulating member is arranged on the thermal insulation shell; the control cabinet is arranged on the outside of the thermal insulation shell, one end of the power cord is electrically connected to the control cabinet, and the other end extends into the interior of the thermal insulation shell through the insulating member and is electrically connected to the electric heating element. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic diagram of an electric thermal energy storage system according to an embodiment of the utility model;

[0027] Figure 2 for Figure 1 AA section view;

[0028] Figure 3 A schematic diagram of a heat storage unit in an electric thermal energy storage system according to an embodiment of the utility model;

[0029] Figure 4 It is a schematic diagram of a heat storage module in an electric thermal energy storage system according to an embodiment of the utility model.

[0030] Description of reference numerals:

[0031] 1. Insulation shell; 101. Heat storage chamber; 1011. Inlet; 1012. Outlet; 21. First heat storage module; 22. Second heat storage module; 23. Nth heat storage module; 201. Heat storage unit; 2011. Placement hole; 2012. Flow hole; 2013. Groove; 3. Heat exchanger; 401. Air inlet main pipe; 402. Air inlet branch pipe; 501. First air inlet valve; 502. Second air inlet valve; 503. Nth air inlet valve; 601. Air outlet main pipe; 602. Air outlet branch pipe; 701. First air outlet valve; 702. Second air outlet valve; 703. Nth air outlet valve; 8. Electric heating element; 9. Fan; 10. Heat insulation; 11. Control cabinet; 12. Power cord; 13. Insulation. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0033] Combine the following Figures 1 to 4 , describing an embodiment of the utility model.

[0034] According to an embodiment of the utility model, on the one hand, an electric thermal energy storage system is provided, including a heat insulation shell 1, a plurality of heat storage modules, a heat exchanger 3, an air inlet duct, an air outlet duct, an electric heating element 8 and a fan 9.

[0035] Among them, the interior of the thermal insulation shell 1 is provided with multiple heat storage chambers 101, and each heat storage chamber 101 is provided with an inlet 1011 and an outlet 1012; multiple heat storage modules are arranged in the heat storage chamber 101 in a one-to-one correspondence; the heat exchanger 3 is arranged outside the thermal insulation shell 1; the two ends of the air inlet duct are respectively connected to the air outlet of the heat exchanger 3 and the inlet 1011 of each heat storage chamber 101; an air inlet valve is arranged on the air inlet path of each inlet 1011; the two ends of the air outlet duct are respectively connected to the outlet 1012 of each heat storage chamber 101 and the air inlet of the heat exchanger 3; an air outlet valve is arranged on the air outlet path of each outlet 1012; the electric heating element 8 is arranged inside each heat storage module; the electric heating element 8 is suitable for electrically connecting to a power supply; and the fan 9 is arranged on the air inlet duct.

[0036] The electric thermal energy storage system of this structure is formed by arranging a plurality of heat storage modules in a one-to-one correspondence in a plurality of heat storage chambers 101, and each heat storage chamber 101 is provided with an inlet 1011 and an outlet 1012, the two sides of the air inlet duct are connected to the air outlet of the heat exchanger 3 and the inlet 1011 of the heat storage chamber 101, and the air outlet duct is connected to the outlet 1012 of the heat storage chamber 101 and the air inlet of the heat exchanger 3, so as to form an air circulation system. An air inlet valve is provided on the air inlet path of each inlet 1011, and an air outlet valve is provided on the air outlet path of each outlet 1012, so that the air inlet and air outlet of each heat storage chamber 101 can be controlled separately. When the electric thermal energy storage system is in operation, when the user's heat consumption is large, the number of heat storage modules for heat release can be increased, and when the user's heat consumption is reduced, the number of heat storage modules for heat release can be reduced, so as to realize the separate control of the heat release amount of the heat storage modules according to the fluctuation of the user's heat load; when one or some heat storage modules fail, other normal heat storage modules can work normally to provide heat; at the same time, multiple heat storage modules are placed in different heat storage chambers 101 respectively, and low-temperature heat exchange air enters the heat storage chamber 101 through the inlet 1011, and the high-temperature gas after heat exchange flows out to the heat exchanger 3 through the outlet 1012, and the low-temperature exchange Hot air enters through the respective inlet 1011 of each heat storage chamber 101 and flows out from the respective outlet 1012 of each heat storage chamber 101. Compared with the method of entering the heat preservation shell 1 from the same total air inlet and flowing out of the heat preservation shell 1 from the same total air outlet, the heat exchange temperature difference at the inlet 1011 of each heat storage chamber 101 can be effectively reduced, and the temperature difference at the outlet 1012 of the heat exchange chamber can be reduced, thereby reducing the thermal stress and large thermal displacement caused by the large temperature difference at the inlet 1011 and the outlet 1012, and preventing the heat storage module from shifting and tipping over, thereby ensuring the stability of the overall structure of the heat storage module. By adjusting the number of heat storage modules for heat release, and adjusting the opening of the air inlet valve or the operating frequency of the fan 9 to adjust the flow of the heat exchange air, two-stage regulation of the heat supply can be achieved, which can effectively improve the regulation range of the heat supply, facilitate the adjustment of the heat supply according to the heat consumption of the user, match the heat supply with the heat consumption, and facilitate the efficient operation of the electric thermal energy storage system; at the same time, by setting up multiple heat storage chambers 101, the heat exchange air enters different heat storage chambers 101 through the air inlet duct, and the hot air after heat exchange flows out from different heat storage chambers 101 to the air outlet duct, which can reduce the running wind resistance and reduce the cost of system operation compared with the method of setting a large-capacity single heat storage module. In addition, compared with the structure of setting a single large-capacity heat storage module, setting up multiple heat storage modules changes the single inlet and single outlet to a structure with multiple inlets 1011 and multiple outlets 1012, and the space of a single heat storage chamber 101 is reduced, which is conducive to the uniformity of the smooth distribution of air in the heat storage chamber 101, so that the air and the heat storage module can be fully and effectively exchanged with heat to improve the heat exchange efficiency.

[0037] like Figure 1As shown, in some embodiments, the air inlet duct includes an air inlet main pipe 401 and multiple air inlet branch pipes 402, and the air outlet duct includes an air outlet main pipe 601 and multiple air outlet branch pipes 602; one side of the air inlet main pipe 401 is connected to the air outlet of the heat exchanger 3, and the air inlet main pipe 401 is connected in parallel with all the inlets 1011 through multiple air inlet branch pipes 402; one side of the air outlet main pipe 601 is connected to the air inlet of the heat exchanger 3, and the air outlet main pipe 601 is connected in parallel with all the outlets 1012 through multiple air outlet branch pipes 602; the fan 9 is arranged on the air inlet main pipe 401. By setting up an air inlet main pipe 401 and multiple air inlet branch pipes 402, as well as setting up an air outlet main pipe 601 and multiple air outlet branch pipes 602, all heat storage modules are connected in parallel, and all heat storage chambers 101 are connected in parallel with a heat exchanger 3. Compared with setting up multiple heat exchangers 3, each heat exchanger 3 is connected to a heat storage chamber 101 through an air inlet duct and an air outlet duct, which can simplify the system structure and save equipment costs.

[0038] In other embodiments, multiple heat exchangers 3 can be provided, and the multiple heat exchangers 3 are connected to each heat storage chamber 101 through multiple air inlet ducts and multiple air outlet ducts, respectively; or a heat exchanger 3 can be provided, and the air outlet and air inlet of the heat exchanger 3 are respectively connected to multi-way pipe joints, the multi-way pipe joint on the air outlet side of the heat exchanger 3 is connected to multiple air inlet ducts, and the multi-way pipe joint on the air inlet side of the heat exchanger 3 is connected to multiple air outlet ducts.

[0039] Optionally, in one embodiment, Figure 1 As shown, the air inlet valve is arranged on the air inlet branch pipe 402, and the air outlet valve is arranged on the air outlet branch pipe 602, so as to control the circulation of the heat exchange air and the size of the heat exchange air flow by controlling the opening of each air inlet valve and air outlet valve.

[0040] In other embodiments, the air inlet valve may also be arranged on the inlet 1011 , and the air outlet valve may be arranged on the outlet 1012 .

[0041] like Figure 1 As shown, in one embodiment, adjacent heat storage chambers 101 are separated by heat insulation 10. The heat insulation 10 separates different heat storage modules, and different heat storage modules can store or release heat independently. Different heat storage modules do not affect each other, and the output power of the electric thermal energy storage system can be adjusted by adjusting the heat release amount of the heat storage module; at the same time, during the heat release period, by adjusting the heat release amount of the heat storage module and the flow rate of the heat exchange medium flowing through different heat storage modules, two-stage regulation is adopted to achieve flexible adjustment of the output power to match the large fluctuation of the user's heat load.

[0042] The heat-insulating shell 1 and the heat-insulating element 10 are both made of heat-insulating materials. For example, the heat-insulating shell 1 and the heat-insulating element 10 can be made of materials with low thermal conductivity, such as lightweight clay bricks, silicon carbonate fibers, rock wool, asbestos boards, and glass fibers.

[0043] Optionally, in one embodiment, Figure 2 As shown, each heat storage module is spaced apart from the heat insulation member 10 to further improve the heat insulation effect between adjacent heat storage modules, while facilitating the circulation of the heat exchange medium in the heat storage chamber 101 to improve the heat exchange effect.

[0044] like Figures 2 to 4 As shown, each heat storage module is provided with a placement hole 2011 and a circulation hole 2012, the electric heating element 8 is arranged in the placement hole 2011, and the circulation hole 2012 is used for heat exchange air circulation. The power supply supplies power to the electric heating element 8, and the electric heating element 8 works to heat the heat storage module. The electric heating element 8 converts electrical energy into heat energy and transfers and stores it in the heat storage module in the form of radiation and heat conduction, so as to store the heat energy in the heat storage module. The air inlet valve is opened, and low-temperature air enters the heat storage chamber 101, and the low-temperature air flows into the circulation hole 2012. The high-temperature heat storage module heats the low-temperature air. The air outlet valve is opened, and the heated high-temperature air flows out from the outlet 1012 to the heat exchanger 3. The cold fluid enters the heat exchanger 3 for heat exchange, and the hot fluid flows out of the heat exchanger 3 to supply heat to the outside.

[0045] like Figure 4 As shown, in one embodiment, each heat storage module is provided with a plurality of layers of placement holes 2011 and a plurality of layers of circulation holes 2012, and the placement holes 2011 and the circulation holes 2012 are arranged orthogonally in space, that is, the circulation path of the air is perpendicular to the extension path of the electric heating element 8, so that the placement holes 2011 and the circulation holes 2012 are arranged in an orderly manner, which is beneficial to sufficient heat exchange during the circulation of low-temperature air.

[0046] At the same time, the placement holes 2011 and the circulation holes 2012 are arranged orthogonally in space, which makes it convenient to increase the heat exchange area by increasing the number of circulation holes 2012, thereby improving the heat exchange effect between the air and the heat storage module during the heat release stage; in addition, the placement holes 2011 and the circulation holes 2012 are arranged orthogonally in space, avoiding that the placement holes 2011 and the circulation holes 2012 are set on the same plane, which can prevent air from entering the placement holes 2011 during the heat release stage to flush the electric heating element 8, and prevent the surface of the electric heating element 8 from rapid oxidation, thereby improving the service life of the electric heating element 8.

[0047] In one embodiment, Figure 1As shown, the placement holes 2011 of all the heat storage modules at the same height extend in the same direction along the same channel, and the electric heating element 8 passes through the placement holes 2011 at the same height of all the heat storage modules, that is, the electric heating element 8 passes through all the insulation components 10 and the heat storage chamber 101. When the electric heating element 8 is working, it can heat multiple groups of heat storage modules at the same time, thereby improving the heating efficiency.

[0048] like Figure 3 and Figure 4 As shown, each heat storage module includes a plurality of heat storage units 201, and the heat storage units 201 are rectangular blocks. The interior of the heat storage units 201 is provided with placement holes 2011 and circulation holes 2012; the outer wall surface of the heat storage unit 201 is provided with grooves 2013, and a plurality of heat storage units 201 are stacked. The grooves 2013 on the adjacent outer wall surfaces of adjacent heat storage units 201 are connected to form circulation holes 2012 located outside the heat storage unit 201, so that the heat exchange air between the adjacent heat storage units 201 can be fully exchanged with the heat storage unit 201, the heat exchange effect is improved, and the operation efficiency of the electric thermal energy storage system is improved. The size of the heat storage capacity of each group of heat storage modules can be arranged in grades according to the actual user heat load fluctuation range to improve the adaptability of heat supply and heat use, and can be combined with standardized heat storage units 201 of the same specifications and different numbers, and the system has good scalability.

[0049] like Figure 3 As shown, a plurality of heat storage units 201 are stacked to form a rectangular block-shaped heat storage module, the placement holes 2011 between each layer of heat storage units 201 are connected in sequence, and the grooves 2013 and the flow holes 2012 between each layer of heat storage units 201 are connected in sequence.

[0050] like Figure 1 As shown, the electric thermal energy storage system also includes a control cabinet 11, a power line 12 and an insulating member 13; the insulating member 13 is arranged on the heat preservation shell 1; the control cabinet 11 is arranged outside the heat preservation shell 1, one end of the power line 12 is electrically connected to the control cabinet 11, and the other end extends into the heat preservation shell 1 through the insulating member 13 and is electrically connected to the electric heating element 8. The control cabinet 11 introduces power into the heat preservation shell 1 to heat the electric heating element 8. The insulating member 13 plays an insulating role in the part where the power line 12 passes through the heat preservation shell 1.

[0051] Optionally, the control cabinet 11 includes a high-voltage control cabinet 11, which introduces a high-voltage power line 12 into the interior of the heat-insulating shell 1, and the high-voltage power line 12 is star-connected with the electric heating element 8. The high-voltage control cabinet 11 is used to ensure the safe operation, start and stop of the electric heating element 8 and the over-temperature protection of the heat storage unit 201.

[0052] In some embodiments, the electric heating element 8 includes an electric heating wire, an electric heating tube or an electric heating belt, and the electric heating element 8 passes through the placement holes 2011 of each layer in sequence in an S-shaped arrangement with the end connected to the end.

[0053] Optionally, the insulating member 13 includes a high-voltage bushing.

[0054] In one embodiment, more than two heat storage modules may be provided, for example, Figure 1 As shown, from left to right, the heat storage modules are the first heat storage module 21, the second heat storage module 22... and the nth heat storage module 23; from left to right, the air inlet valves are the first air inlet valve 501, the second air inlet valve 502... and the nth air inlet valve 503; and the air outlet valves are the first air outlet valve 701, the second air outlet valve 702... and the nth air outlet valve 703.

[0055] The heat exchanger 3 includes an air-water heat exchanger, an air-oil heat exchanger, an air-air heat exchanger or a steam generator, and can provide hot water, hot oil, hot air or steam to the user.

[0056] Optionally, the fan 9 comprises a circulation fan 9 .

[0057] The operating status of each heat storage module, the corresponding valve opening of the air inlet valve and the air outlet valve, the matching mode of the speed of the circulating fan 9 and the output temperature of the heated fluid of the heat exchanger 3 form a logical relationship to achieve continuous control of the output temperature of the heat exchanger 3.

[0058] The working process of the electric thermal energy storage system is as follows:

[0059] During heat charging, all air inlet valves and air outlet valves are in a closed state, the circulating fan 9 stops working, and the green electricity from the high-voltage power grid is introduced into the interior of the heat preservation shell 1 through the high-voltage control cabinet 11 and the high-voltage bushing No. 2 power line 12. The high-voltage power line 12 is electrically connected to the electric heating element 8, and the electric heating element 8 converts electrical energy into heat energy and stores it in the heat storage module. The heat storage module is heated to a high temperature state.

[0060] When the user's heat load is relatively stable, when releasing heat, a grouped step-by-step heat release mode is adopted. The first air inlet valve 501 and the first air outlet valve 701 are opened first, and the other air inlet valves and air outlet valves are in a closed state. The circulating fan 9 is started to pressurize the low-temperature air and send it into the first heat storage module 21. The low-temperature air is heated after passing through the circulation hole 2012. The heated high-temperature air flows into the heat exchanger 3 through the first air outlet valve 701, the air outlet branch pipe 602 and the air outlet main pipe 601 to supply heat to the outside. When the temperature of the outlet 1012 of the first heat storage module 21 drops to the target value, the second air inlet valve 502 and the second air outlet valve 702 are opened immediately, and the opening of the first air inlet valve 501 and the second air inlet valve 502 are gradually reduced to closed, and the heat storage device enters the heat release mode of the second heat storage module 22, and so on, until the heat release of the nth heat storage module 23 is completed, that is, the heat release of the entire electric thermal energy storage system is completed. Since the electric thermal energy storage system adopts grouped and step-by-step heat release, the problem of high energy consumption of the circulation fan 9 caused by the need for large flow rate heat extraction in the later stage of heat release of the traditional single-group heat storage module is reduced, thereby saving operating costs.

[0061] When the user's heat load fluctuates greatly, the heating demand can no longer be met by simply adjusting the frequency of the circulating fan 9 and adjusting the valve openings of the air inlet valve and the air outlet valve. At this time, the heat storage modules that are set in stages according to the previous heat load fluctuation data can be grouped to release heat, that is, the output heat load is adjusted for the first time using the different heat release quantities of the parallel heat storage modules, and then the circulating fan 9 and the valve opening are used to adjust the output heat load for the second time. Finally, through the first rough adjustment and the second fine adjustment, a highly dynamic match between the heating of the electric thermal energy storage system and the user's heat fluctuation load is achieved, thereby improving the overall operating efficiency of the heat storage heating system.

[0062] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An electric thermal energy storage system, characterized in that: include: A heat-insulating shell (1) having a plurality of heat storage chambers (101) therein, each heat storage chamber (101) being provided with an inlet (1011) and an outlet (1012); A plurality of heat storage modules are arranged in the heat storage chamber (101) in a one-to-one correspondence; A heat exchanger (3) is arranged outside the heat-insulating shell (1); An air inlet duct, the two ends of which are respectively connected to the air outlet of the heat exchanger (3) and the inlet (1011) of each heat storage chamber (101); an air inlet valve is provided on the air inlet path of each inlet (1011); An air outlet duct, the two ends of which are respectively connected to the outlet (1012) of each heat storage chamber (101) and the air inlet of the heat exchanger (3); an air outlet valve is provided on the air outlet path of each outlet (1012); An electric heating element (8) is arranged inside each of the heat storage modules; the electric heating element (8) is suitable for being electrically connected to a power source; A fan (9) is arranged on the air inlet duct.

2. The electric thermal energy storage system according to claim 1, characterized in that: The air inlet duct comprises an air inlet main pipe (401) and a plurality of air inlet branch pipes (402), and the air outlet duct comprises an air outlet main pipe (601) and a plurality of air outlet branch pipes (602); one side of the air inlet main pipe (401) is connected to the air outlet of the heat exchanger (3), and the air inlet main pipe (401) is connected in parallel with all the inlets (1011) through the plurality of air inlet branch pipes (402); one side of the air outlet main pipe (601) is connected to the air inlet of the heat exchanger (3), and the air outlet main pipe (601) is connected in parallel with all the outlets (1012) through the plurality of air outlet branch pipes (602); the fan (9) is arranged on the air inlet main pipe (401).

3. The electric thermal energy storage system according to claim 2, characterized in that: The air inlet valve is arranged on the air inlet branch pipe (402), and the air outlet valve is arranged on the air outlet branch pipe (602).

4. The electric thermal energy storage system according to any one of claims 1 to 3, characterized in that: Adjacent heat storage chambers (101) are separated by heat insulating members (10).

5. The electric thermal energy storage system according to claim 4, characterized in that: Each of the heat storage modules is spaced apart from the heat insulating member (10).

6. The electric thermal energy storage system according to any one of claims 1 to 3, characterized in that: Each of the heat storage modules is provided with a placement hole (2011) and a circulation hole (2012); the electric heating element (8) is arranged in the placement hole (2011); and the circulation hole (2012) is used for heat exchange air to circulate.

7. The electric thermal energy storage system according to claim 6, characterized in that: Each of the heat storage modules is provided with a plurality of placement holes (2011) and a plurality of circulation holes (2012), and the placement holes (2011) and the circulation holes (2012) are arranged in a spatially orthogonal manner.

8. The electric thermal energy storage system according to claim 7, characterized in that: The placement holes (2011) located at the same height of all the heat storage modules extend in the same direction along the same channel, and the electric heating element (8) is arranged through the placement holes (2011) located at the same height of all the heat storage modules.

9. The electric thermal energy storage system according to claim 6, characterized in that: Each of the heat storage modules comprises a plurality of heat storage units (201), the heat storage units (201) being in the shape of a rectangular block, the interior of the heat storage unit (201) being provided with the placement hole (2011) and the circulation hole (2012); a groove (2013) being provided on the outer wall surface of the heat storage unit (201), and a plurality of the heat storage units (201) being stacked, the grooves (2013) on the adjacent outer wall surfaces of adjacent heat storage units (201) being butted together to form the circulation hole (2012) located outside the heat storage unit (201).

10. The electric thermal energy storage system according to any one of claims 1 to 3, characterized in that: It also comprises a control cabinet (11), a power line (12) and an insulating member (13); the insulating member (13) is arranged on the heat-insulating shell (1); the control cabinet (11) is arranged on the outside of the heat-insulating shell (1); one end of the power line (12) is electrically connected to the control cabinet (11), and the other end extends into the interior of the heat-insulating shell (1) through the insulating member (13) and is electrically connected to the electric heating element (8).

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