A solid electric heat storage device with energy storage bodies connected in series

Abstract

The present invention belongs to the field of clean energy, and specifically relates to a solid electric heat storage device with energy storage bodies connected in series, which includes a device housing, a device bottom bracket, a heat circulation fan, a heat exchange device and an energy storage body structure. An adiabatic material layer is provided on the inner side surface of the device housing. The energy storage body structure is divided into a low-temperature zone energy storage body and a high-temperature zone energy storage body, both of which are arranged in the internal space formed by the adiabatic material layer. The low-temperature zone energy storage body is placed at a position close to the air outlet of the heat circulation fan, and the high-temperature zone energy storage body is placed at a position close to the air inlet end of the heat exchange device. Compared with the traditional single-energy storage body solid electric heat storage device, under the condition of the same volume of the energy storage body, the present invention adopts a structure in which the high-temperature zone energy storage body and the low-temperature zone energy storage body are connected in series, which can reduce the internal temperature gradient range of the energy storage body, improve the thermal efficiency of the whole device, effectively improve the safety factor, reduce the weight, reduce the cost, and greatly improve the economy.

Description

Technical Field

[0001] The present invention belongs to the field of clean energy, and specifically relates to a solid electric heat storage device with energy storage bodies connected in series. Background Art

[0002] In the heat exchange process inside the solid electric heat storage device, the hot circulation fan pressurizes and blows cold air into one side of the energy storage body, and the air then blows out from the other side of the energy storage body to complete heat exchange. During the heat exchange process, the air gradually heats up from the blowing side to the blowing-out side, and there is a temperature gradient in the energy storage body from low to high.

[0003] In the traditional heat storage device with a single energy storage body, the energy storage body is a single continuous whole, and the electric heating wires in the heating unit can only be made into a unified model and placed inside the energy storage body. This setting will cause the following faults, which have not been properly solved at present.

[0004] (1) After the air undergoes continuous heat exchange inside the energy storage body, the temperature of the energy storage body near the air outlet of the hot circulation fan is relatively low, while the temperature of the energy storage body near the air inlet end of the heat exchange device is relatively high, and the difference can reach more than 200 °C or even higher. Therefore, a large temperature gradient appears inside the energy storage body, that is, the so-called low-temperature zone and high-temperature zone. Due to the influence of the temperature gradient, the bottom temperature of the high-temperature zone is relatively high. When the heating unit works, the low-temperature zone and the high-temperature zone will heat up synchronously. When the temperature accumulates to a certain value after synchronous heating, it will exceed the limit service temperature of the heat storage bricks and electric heating wires, which is extremely easy to cause damage, bringing potential hazards to the operation of the equipment and reducing safety.

[0005] (2) When a large temperature gradient appears inside the energy storage body, the temperature of the heat storage bricks in the low-temperature zone remains at a relatively low level for a long time. When the temperature of the heat storage bricks is low, its specific heat capacity is also low, that is, the heat storage amount of the heat storage bricks per unit volume is also small, which deviates greatly from the design. During the heat storage process, the energy storage body in the low-temperature zone can never reach a high temperature state, and its heat storage amount cannot meet the design requirements. In addition, when the heat storage bricks are in a low-temperature state, their thermal conductivity is large, that is, the heat release speed is fast, which violates the logic of slow heat release of the electric heat storage device. Therefore, in this case, the energy storage cycle efficiency of the energy storage body does not meet the standard, and only by increasing the total mass of the heat storage bricks can the heat storage amount be increased, but the cost is increased and the economy is poor.

[0006] (3) The electric heating wires installed inside the energy storage body also each have a temperature gradient. When heated by electricity to a certain temperature, the deformation in the high-temperature area is significantly greater than that in the low-temperature area. As a result, the high-temperature area and the low-temperature area cannot deform simultaneously, and after deformation, they cannot return to their original shapes. After a period of time, the pitch of the electric heating wire in the high-temperature area will slowly squeeze and pile up and then collapse. After collapse, it will rapidly heat up under the action of the energized current, accelerating aging and shortening the service life. In addition, the extremely high temperature can melt the heat storage bricks and damage the electric heating wires at the same time, resulting in system out-of-control and unable to operate normally. Even if the surface load of a single electric heating wire is designed very low, the deformation problem cannot be solved, and it increases the cost of the electric heating wire, with poor economy. Summary of the Invention

[0007] In view of the above problems, the purpose of the present invention is to provide a solid electric heat storage device with energy storage bodies connected in series.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A solid electric heat storage device with energy storage bodies connected in series, comprising a device housing, a device bottom bracket, a heat circulation fan, a heat exchange device and an energy storage body structure. The heat circulation fan and the heat exchange device are respectively installed inside the device bottom bracket, and the device bottom bracket is connected to the device housing;

[0010] An adiabatic material layer is provided on the inner side surface of the device housing, and the internal space formed by the adiabatic material layer at least includes a high-temperature air chamber and a low-temperature air chamber;

[0011] The heat exchange device has an air inlet end, an air outlet end, a water outlet pipe and a water inlet pipe connected to an external pipe network. The air inlet end of the heat exchange device is communicated with the high-temperature air chamber, the air outlet end of the heat exchange device is communicated with the air inlet of the heat circulation fan through a low-temperature air duct, the air outlet of the heat circulation fan is communicated with the low-temperature air chamber, and the air inlet end of the heat exchange device and the air outlet of the heat circulation fan are respectively arranged at two corresponding positions on the bottom surface of the adiabatic material layer;

[0012] The energy storage body structure is divided into a low-temperature area energy storage body and a high-temperature area energy storage body both arranged in the internal space formed by the adiabatic material layer. The low-temperature area energy storage body is placed at a position close to the air outlet of the heat circulation fan, and the high-temperature area energy storage body is placed at a position close to the air inlet end of the heat exchange device;

[0013] Air enters the low-temperature air chamber from the air outlet of the heat circulation fan, sequentially passes through the low-temperature zone energy storage body and the high-temperature zone energy storage body for heat exchange, then passes through the high-temperature air chamber and is discharged from the air inlet end of the heat exchange device, and then exchanges heat through the heat exchange device. After that, it sequentially passes through the low-temperature air duct and the heat circulation fan, returns to the low-temperature air chamber, and passes through the low-temperature zone energy storage body and the high-temperature zone energy storage body again, and so on in a cycle.

[0014] A wind shield wall A is provided on the outer periphery of one end of the low-temperature zone energy storage body close to the air outlet of the heat circulation fan, and a wind shield wall B is provided on the outer periphery of one end of the high-temperature zone energy storage body close to the air outlet of the heat circulation fan. The wind shield wall A and the wind shield wall B divide the internal space formed by the heat insulation material layer into space A, space B, and space C in sequence. Space A is the low-temperature air chamber, space C is the high-temperature air chamber, and space B is the medium-temperature air chamber;

[0015] Air enters space A from the air outlet of the heat circulation fan, first passes through the low-temperature zone energy storage body and enters space B, then passes through the high-temperature zone energy storage body and enters space C, and then is discharged from the air inlet end of the heat exchange device.

[0016] A temperature sensor A is installed on the device housing, and the temperature sensor A is inserted into space B.

[0017] A temperature sensor B is installed on the device housing, and the temperature sensor B is inserted into space C.

[0018] The low-temperature zone energy storage body includes low-temperature zone heat storage bricks, a low-temperature zone heating unit, and a low-temperature zone high-temperature and high-voltage incoming line device. The high-temperature zone energy storage body includes high-temperature zone heat storage bricks, a high-temperature zone heating unit, and a high-temperature zone high-temperature and high-voltage incoming line device.

[0019] The energy storage cycle efficiency of the high-temperature zone energy storage body is higher than that of the low-temperature zone energy storage body.

[0020] The heating electric power of the high-temperature zone energy storage body is less than that of the low-temperature zone energy storage body.

[0021] The overall set thickness of the high-temperature zone energy storage body is less than that of the low-temperature zone energy storage body.

[0022] The advantages and positive effects of the present invention are:

[0023] Compared with the traditional single energy storage body electric heat storage device, under the condition of the same volume of the energy storage body, due to the structure of series setting of the high-temperature zone energy storage body and the low-temperature zone energy storage body, the temperature gradient range inside the energy storage body can be reduced, the thermal efficiency of the whole device can be improved, the safety factor can be improved, the weight can be reduced, the cost can be reduced, and the economy can be greatly improved. Description of the Drawings

[0024] Figure 1 is the overall structural schematic diagram of the present invention;

[0025] Figure 2 is the structural schematic diagram of the energy storage body of the present invention.

[0026] In the figure: 1 is the device housing, 2 is the device bottom bracket, 3 is the thermal circulation fan, 4 is the heat exchange device, 401 is the water outlet pipe, 402 is the water inlet pipe, 5 is the low-temperature air duct, 6 is the heat insulation material layer, 7 is the low-temperature area energy storage body, 8 is the high-temperature area energy storage body, 9 is the windbreak wall A, 10 is the windbreak wall B, 11 is the temperature sensor A, 12 is the temperature sensor B;

[0027] 001 is the spacer layer heat storage brick, 002 is the brick hole layer heat storage brick, 003 is the heating wire, 004 is the connecting plate A, 005 is the connecting plate B, 006 is the heat exchange channel. Specific embodiments

[0028] The following combines the attached Figure 1-2 to further elaborate on the present invention.

[0029] A solid electric heat storage device with series-connected energy storage bodies, as Figure 1 shown, in this embodiment, it includes a device housing 1, a device bottom bracket 2, a thermal circulation fan 3, a heat exchange device 4 and an energy storage body structure. The thermal circulation fan 3 and the heat exchange device 4 are respectively installed inside the device bottom bracket 2. The thermal circulation fan 3 and the heat exchange device 4 are both commercially available products, and the device bottom bracket 2 is connected to the device housing 1.

[0030] A heat insulation material layer 6 is provided on the inner side surface of the device housing 1. The heat insulation material layer 6 uses commonly used heat insulation materials in the prior art, such as aluminosilicate fiber materials, etc. The setting methods of the device housing 1 and the heat insulation material layer 6 are also in the prior art. In this embodiment, the internal space formed by the heat insulation material layer 6 at least includes a high-temperature air chamber and a low-temperature air chamber.

[0031] The heat exchange device 4 has an air inlet end, an air outlet end, a water outlet pipe 401 and a water inlet pipe 402 connected to the external pipe network. The air inlet end of the heat exchange device 4 is communicated with the high-temperature air chamber. The air outlet end of the heat exchange device 4 is communicated with the air inlet of the thermal circulation fan 3 through the low-temperature air duct 5. The air outlet of the thermal circulation fan 3 is communicated with the low-temperature air chamber. The air inlet end of the heat exchange device 4 and the air outlet of the thermal circulation fan 3 are respectively arranged at corresponding positions on both sides of the bottom surface of the heat insulation material layer 6.

[0032] In this embodiment, three groups of energy storage body structures are provided according to the operating voltage level, and they are the same. They are all arranged in the internal space formed by the heat insulation material layer 6. Each group of energy storage body structures is divided into a low-temperature zone energy storage body 7 and a high-temperature zone energy storage body 8. The low-temperature zone energy storage body 7 is placed at a position close to the air outlet of the heat circulation fan 3, and the high-temperature zone energy storage body 8 is placed at a position close to the air inlet end of the heat exchange device 4.

[0033] Air enters the low-temperature air chamber from the air outlet of the heat circulation fan 3, sequentially passes through the low-temperature zone energy storage body 7 and the high-temperature zone energy storage body 8 for heat exchange, then is discharged from the air inlet end of the heat exchange device 4 through the high-temperature air chamber, and then undergoes heat exchange through the heat exchange device 4. After that, it sequentially passes through the low-temperature air duct 5 and the heat circulation fan 3 to return to the low-temperature air chamber and passes through the low-temperature zone energy storage body 7 and the high-temperature zone energy storage body 8 again, and this cycle continues.

[0034] Specifically, in this embodiment, a wind blocking wall A 9 is provided on the outer periphery of one end of the low-temperature zone energy storage body 7 close to the air outlet of the heat circulation fan 3, and a wind blocking wall B 10 is provided on the outer periphery of one end of the high-temperature zone energy storage body 8 close to the air outlet of the heat circulation fan 3. The wind blocking wall A 9 and the wind blocking wall B 10 divide the internal space formed by the heat insulation material layer 6 into space A, space B, and space C in sequence. Space A is the low-temperature air chamber, space C is the high-temperature air chamber, and space B is the medium-temperature air chamber. Air enters space A from the air outlet of the heat circulation fan 3, first passes through the low-temperature zone energy storage body 7 to enter space B, then passes through the high-temperature zone energy storage body 8 to enter space C, and then is discharged from the air inlet end of the heat exchange device 4.

[0035] Specifically, in this embodiment, the low-temperature zone energy storage body 7 includes low-temperature zone heat storage bricks, a low-temperature zone heating unit, and a low-temperature zone high-temperature and high-voltage inlet device, and the high-temperature zone energy storage body 8 includes high-temperature zone heat storage bricks, a high-temperature zone heating unit, and a high-temperature zone high-temperature and high-voltage inlet device. In this embodiment, both the low-temperature zone heating unit and the high-temperature zone heating unit adopt the heating unit products mainly using electric heating wires in the prior art.

[0036] In this embodiment, the setting structures of the high-temperature zone energy storage body 8 and the low-temperature zone energy storage body 7 are the same, such as Figure 2As shown in the figure, each energy storage body includes a heat storage brick stack, heating wires 003, connecting plate A 004, connecting plate B 005, and a high-temperature and high-voltage inlet device. The heat storage brick stack is divided into multiple layers of spaced heat storage bricks 001 and multiple layers of brick-hole heat storage bricks 002. The spaced heat storage bricks 001 and the brick-hole heat storage bricks 002 are arranged at intervals. Each layer of brick-hole heat storage bricks 002 is provided with a plurality of heat exchange channels 006, and heating wires 003 are installed in the heat exchange channels 006. Connecting plate A 004 is installed on each layer of spaced heat storage bricks 001. The heating wires 003 on each layer of brick-hole heat storage bricks 002 are connected in parallel to the connecting plate A 004 of the adjacent lower layer of spaced heat storage bricks 001. The connecting plate A 004 of each layer of spaced heat storage bricks 001 is connected in series through multiple connecting plates B 005 and is connected to the high-temperature and high-voltage inlet device after series connection. The setting of the high-temperature and high-voltage inlet device is prior art.

[0037] Specifically, in this embodiment, three temperature sensors A11 are installed on the device housing 1. The three temperature sensors A11 are respectively inserted into the space B, and each temperature sensor A11 is respectively arranged between the low-temperature zone energy storage body 7 and the high-temperature zone energy storage body 8 corresponding to one of the groups of energy storage body structures. The purpose of setting the temperature sensors A11 is to monitor the temperature change of the space B. When any one of the readings reaches the upper limit of the set value, all the heating units of the low-temperature zone energy storage body 7 are immediately powered off. Six temperature sensors B12 are installed on the device housing 1, and the temperature sensors B12 are all inserted into the space C. The setting positions of every two temperature sensors B12 respectively correspond to the setting positions of the high-temperature zone energy storage body 8 of one group. For the two temperature sensors B12 corresponding to the setting positions of the high-temperature zone energy storage body 8 of the same group, one corresponds to the upper part of the high-temperature zone energy storage body 8, and the other corresponds to the middle part of the high-temperature zone energy storage body 8. The purpose of setting the temperature sensors B12 is to monitor the temperature change of the space C at the same time. When the temperature of the space C reaches the upper limit of the set value, the heating units of the high-temperature zone energy storage body 8 are first powered off, and then the temperature change of the entire electric heat storage device is observed to determine whether to power on the heating units of the high-temperature zone energy storage body 8.

[0038] Specifically, in this embodiment, the energy storage cycle efficiency of the high-temperature zone energy storage body 8 is higher than that of the low-temperature zone energy storage body 7, the heating electric power of the high-temperature zone energy storage body 8 is less than that of the low-temperature zone energy storage body 7, and the overall set thickness of the high-temperature zone energy storage body 8 is less than that of the low-temperature zone energy storage body 7. The heating electric power of the low-temperature zone energy storage body 7 is set to be greater than that of the high-temperature zone energy storage body 8. Since the heat storage temperature upper limit control means of the low-temperature zone energy storage body 7 is relatively mature and the probability of failure is extremely low, while increasing the electric power of the heating wire, the surface load of the heating wire can also be increased by 15-20%. Correspondingly, the weight of the heating wire is reduced, that is, on the premise of increasing the power, the weight is reduced, the cost is reduced, and the economy is greatly improved. The high-temperature zone energy storage body 8 and the low-temperature zone energy storage body 7 are connected in series. Its function is to narrow the internal gradient range of the energy storage body. When the system is started each time, first, the heating unit of the high-temperature zone energy storage body 8 is powered on for heating. As the external heat demand is met, the heat circulation fan 3 will run stably at a lower frequency. Then, the heating unit of the low-temperature zone energy storage body 7 is powered on. At this time, the heating units of the two energy storage bodies work simultaneously, and the numerical change of the monitoring temperature sensor B12 is monitored. When the set warning value is reached, the heating unit of the high-temperature zone energy storage body 8 is powered off. The heating unit of the low-temperature zone energy storage body 7 continues to be powered on for heating. Part of the generated heat is absorbed and stored by the low-temperature zone energy storage body 7, and the remaining heat is transferred through air flow. The high-temperature air continues to heat the high-temperature zone energy storage body 8, so that the overall temperature of the high-temperature zone energy storage body 8 can be maintained at a relatively high temperature. In addition, the specific heat capacity of the heat storage brick increases with the increase of the ambient temperature. It is 1.05 times that at 500°C and 1.12 times that at 200°C at 700°C. Therefore, the heat storage capacity per unit volume of the high-temperature zone energy storage body 8 is enhanced, the heat release time is extended, the heat release capacity is improved, and the thermal efficiency of the whole system is improved. The set thickness of the high-temperature zone energy storage body 8 is less than that of the low-temperature zone energy storage body 7. The purpose of the larger thickness of the low-temperature zone energy storage body 7 is to control and solve the temperature gradient of the whole system within a single energy storage body, so that the high-temperature zone energy storage body 8 is not affected by the temperature gradient; during the actual operation process, by monitoring the numerical change of the temperature sensor A11, before reaching the warning value, the heating unit of the low-temperature zone energy storage body 7 can continue to heat. Through air flow, the hot air first enters the space B, and then passes through the heat exchange channel 006 of the high-temperature zone energy storage body 8 to heat the internal heat storage bricks and heating wires. The overall heat storage capacity of the high-temperature zone energy storage body 8 continues to increase, and the heat storage capacity is improved.For the monitoring of temperature sensor A11 and temperature sensor B12, the set warning values for both are such that the value of temperature sensor A11 should be higher than that of temperature sensor B12, and the difference range is between 150 - 200 °C; each time the heat storage device operates, the heating unit of the high-temperature zone energy storage body 8 is first powered on, and after a period of time, the heating unit of the low-temperature zone energy storage body 7 is also powered on. In this way, temperature sensor B12 will reach the warning value within a certain period of time. At this time, the heating unit of the high-temperature zone energy storage body 8 is immediately powered off and will not be powered on again during the subsequent process. Since the low-temperature zone energy storage body 7 is close to the air inlet end of the heat circulation fan 3 and the average temperature of the energy storage body is at a low level, the probability of failure is extremely low, and it can be powered on for heating for a long time. The heat generated by it can be conducted and absorbed by the energy storage bodies and the internal space of the entire system. In addition, the real-time detection value of temperature sensor A11 is also a means to ensure the safe operation of the heating unit of the low-temperature zone energy storage body 7, improving the safety factor of the system.

Claims

1. A solid electric heat storage device with energy storage bodies connected in series, characterized in that: It includes a device housing (1), a device bottom bracket (2), a thermal circulation fan (3), a heat exchange device (4) and an energy storage body structure. The thermal circulation fan (3) and the heat exchange device (4) are respectively installed inside the device bottom bracket (2), and the device bottom bracket (2) is connected to the device housing (1). An adiabatic material layer (6) is provided on the inner side surface of the device housing (1), and the internal space formed by the adiabatic material layer (6) at least includes a high-temperature air chamber and a low-temperature air chamber. The heat exchange device (4) has an air inlet end, an air outlet end, a water outlet pipe (401) and a water inlet pipe (402) connected to an external pipe network. The air inlet end of the heat exchange device (4) communicates with the high-temperature air chamber. The air outlet end of the heat exchange device (4) communicates with the air inlet of the thermal circulation fan (3) through a low-temperature air duct (5). The air outlet of the thermal circulation fan (3) communicates with the low-temperature air chamber. The air inlet end of the heat exchange device (4) and the air outlet of the thermal circulation fan (3) are respectively arranged at two corresponding positions on the bottom surface of the adiabatic material layer (6). The energy storage body structure is divided into a low-temperature zone energy storage body (7) and a high-temperature zone energy storage body (8) both arranged in the internal space formed by the adiabatic material layer (6). The low-temperature zone energy storage body (7) is placed at a position close to the air outlet of the thermal circulation fan (3), and the high-temperature zone energy storage body (8) is placed at a position close to the air inlet end of the heat exchange device (4). Air enters the low-temperature air chamber from the air outlet of the thermal circulation fan (3), sequentially passes through the low-temperature zone energy storage body (7) and the high-temperature zone energy storage body (8) for heat exchange, then passes through the high-temperature air chamber and is discharged from the air inlet end of the heat exchange device (4), and then undergoes heat exchange through the heat exchange device (4). After that, it sequentially passes through the low-temperature air duct (5) and the thermal circulation fan (3) to return to the low-temperature air chamber and passes through the low-temperature zone energy storage body (7) and the high-temperature zone energy storage body (8) again, and this cycle repeats. The energy storage cycle efficiency of the high-temperature zone energy storage body (8) is higher than that of the low-temperature zone energy storage body (7). The heating electric power of the high-temperature zone energy storage body (8) is less than that of the low-temperature zone energy storage body (7). The overall set thickness of the high-temperature zone energy storage body (8) is less than that of the low-temperature zone energy storage body (7).

2. The solid electric heat storage device with energy storage bodies connected in series according to claim 1, wherein: A wind blocking wall A (9) is provided on the outer periphery of one end of the low-temperature zone energy storage body (7) close to the air outlet of the thermal circulation fan (3). A wind blocking wall B (10) is provided on the outer periphery of one end of the high-temperature zone energy storage body (8) close to the air outlet of the thermal circulation fan (3). The wind blocking wall A (9) and the wind blocking wall B (10) sequentially divide the internal space formed by the adiabatic material layer (6) into space A, space B and space C. Space A is the low-temperature air chamber, space C is the high-temperature air chamber, and space B is the medium-temperature air chamber. Air enters space A from the air outlet of the thermal circulation fan (3), first passes through the low-temperature zone energy storage body (7) and enters space B, then passes through the high-temperature zone energy storage body (8) and enters space C, and then is discharged from the air inlet end of the heat exchange device (4).

3. The solid electric heat storage device with energy storage bodies connected in series according to claim 2, wherein: A temperature sensor A (11) is installed on the device housing (1), and the temperature sensor A (11) is inserted into space B.

4. The solid electric heat storage device with energy storage bodies connected in series according to claim 2, characterized in that: A temperature sensor B (12) is installed on the device housing (1), and the temperature sensor B (12) is inserted into space C.

5. The solid electric heat storage device with energy storage bodies connected in series according to claim 1, characterized in that: The low-temperature zone energy storage body (7) includes low-temperature zone heat storage bricks, a low-temperature zone heating unit and a low-temperature zone high-temperature and high-voltage inlet device, and the high-temperature zone energy storage body (8) includes high-temperature zone heat storage bricks, a high-temperature zone heating unit and a high-temperature zone high-temperature and high-voltage inlet device.

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