Electric boiler heat storage system and power grid peak shaving method

Abstract

This invention discloses an electric boiler thermal storage system and a power grid peak-shaving method. The electric boiler thermal storage system includes a thermal power plant, a primary heating network station, a thermal storage component, and a water storage tank. The primary heating network station has a first inlet and a second inlet. The first inlet is adapted to be connected to a heating pipe so that hot water flowing out of the primary heating network station can flow into the heating pipe to provide heat energy to users. Alternatively, the second inlet is adapted to be connected to a return water pipe so that return water in the return water pipe can flow into the primary heating network station to heat the return water. The thermal storage component has a first channel and a second channel that are independent of each other and capable of heat exchange. One end of the first channel is connected to the first inlet of the primary heating network station so that hot water flowing out of the primary heating network station can flow into the first channel. One end of the second channel is adapted to be connected to an electrode boiler so that steam generated by the electrode boiler can flow into the second channel to heat the hot water in the first channel. The electric boiler thermal storage system of this invention has the advantages of flexible and variable adjustment schemes, no impact on the heat exchange capacity of the primary heat exchange station, and low investment cost.

Description

Technical Field

[0001] This invention belongs to the field of combined heat and power, specifically relating to an electric boiler thermal storage system and a power grid peak shaving method. Background Technology

[0002] In recent years, the installed capacity of combined heat and power (CHP) plants in most parts of my country's power market has been excessive. Especially during the winter heating season, in order to prioritize the smooth operation of urban centralized heating, CHP thermal power generating units must operate under the minimum operating conditions approved by the power grid, including electrical and thermal loads. To ensure the minimum thermal load of the units, CHP units cannot reduce their electrical load, and the power grid's load adjustment space is limited, resulting in the curtailment of wind and solar power, especially in areas with long heating seasons.

[0003] Therefore, in related technologies, thermal power plants have poor peak-shaving capabilities and high operating costs. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, embodiments of the present invention propose an electric boiler thermal storage system with low operating costs and strong peak-shaving capacity for thermal power plants.

[0006] This invention proposes a simple and low-cost method for grid peak shaving.

[0007] According to an embodiment of the present invention, an electric boiler thermal storage system includes: a thermal power plant for generating electrical energy and thermal energy, the thermal power plant including a heating network head station, the heating network head station having a first inlet and a second inlet, the first inlet of the heating network head station being adapted to be connected to a heating pipe so that hot water flowing out of the heating network head station flows into the heating pipe to provide thermal energy to users, or the second inlet of the heating network head station being adapted to be connected to a return water pipe so that return water in the return water pipe flows into the heating network head station to heat the return water; a thermal storage component and a water storage tank, the thermal storage component having a first channel and a second channel that are independent of each other and capable of heat exchange, wherein during the non-heating season, one end of the first channel is disconnected from the first inlet of the heating network head station, the thermal power plant only generates electrical load, and the electric boiler thermal storage system does not operate; in the electric boiler thermal storage system During the heating season, one end of the first channel is connected to the first outlet of the heating network's first station, allowing some of the hot water flowing out of the first station to flow into the first channel. One end of the second channel is adapted to be connected to the electrode boiler, allowing steam generated by the electrode boiler to flow into the second channel to heat the hot water in the first channel. The electric boiler thermal storage system has a first state and a second state during peak-shaving periods. In the first state, the other end of the first channel is connected to the heating pipe, allowing the heated hot water to flow into the heating pipe to provide heat energy to users. In the second state, the other end of the first channel is connected to both the heating pipe and a water storage tank, allowing a portion of the hot water flowing out of the first channel to flow into the heating pipe and another portion to flow into the water storage tank.

[0008] The electric boiler thermal storage system of this invention includes a heat network primary station, thermal storage components, and a water storage tank. This allows the thermal power plant to operate under low electrical load conditions, ensuring the heating capacity of the electric boiler thermal storage system, enhancing the peak-shaving capacity of the thermal power plant, and reducing the operating costs of the thermal power plant.

[0009] In some embodiments, there are multiple heat storage components, and at least one of the multiple heat storage components is connected to the first outlet of the heating network first station so that hot water flowing out of the heating network first station flows into at least one of the multiple heat storage components. During the peak heating period, at least one of the heat storage components is connected to the heating pipe. During the beginning and end of the heating period, at least one of the heat storage components is connected to the heating pipe and the water storage tank respectively.

[0010] In some embodiments, the heating network primary station includes a first heating network primary station and a second heating network primary station. Both the first heating network primary station and the second heating network primary station have a first outlet and a second outlet. A portion of the plurality of heat storage components is respectively connected to the first outlet of the first heating network primary station and the heating pipe, so that a portion of the plurality of heat storage components heats the hot water flowing out of the first heating network primary station. Another portion of the plurality of heat storage components is respectively connected to the first outlet of the second heating network primary station and the heating pipe, so that another portion of the plurality of heat storage components heats the hot water flowing out of the second heating network primary station.

[0011] In some embodiments, the electric boiler thermal storage system further includes a detection component, the two ends of which are respectively connected to the thermal storage component and the heating pipe, so that the detection component can detect the flow rate of hot water flowing into the heating pipe through the thermal storage component.

[0012] In some embodiments, the first state includes a first sub-state and a second sub-state. During the peak-shaving period of the heating season, the electric boiler thermal storage system is in the first sub-state, with the top of the water storage tank connected to the first outlet of the heating network's primary station so that excess hot water generated by the primary station flows into the water storage tank, and the bottom of the water storage tank connected to the second outlet of the heating network's primary station so that water in the water storage tank flows into the primary station. During the non-peak-shaving period of the heating season, the electric boiler thermal storage system is in the second sub-state, with the top of the water storage tank connected to the heating pipe so that water in the water storage tank flows into the heating pipe, and the bottom of the water storage tank connected to the return water pipe so that water in the return water pipe flows into the water storage tank.

[0013] In some embodiments, the second state includes a third sub-state and a fourth sub-state. During the peak-shaving period at the beginning and end of the heating season, the electric boiler heat storage system is in the third sub-state. The top of the water storage tank is connected to the other end of the first channel of the heat storage component so that excess hot water in the first channel of the heat storage component flows into the water storage tank. The bottom of the water storage tank is connected to the second outlet of the first station of the heating network so that water in the water storage tank flows into the first station of the heating network. During the non-peak-shaving period at the beginning and end of the heating season, the electric boiler heat storage system is in the fourth sub-state. The top of the water storage tank is connected to the heating pipe so that water in the water storage tank flows into the heating pipe. The bottom of the water storage tank is connected to the return water pipe so that water in the return water pipe flows into the water storage tank.

[0014] In some embodiments, the electric boiler thermal storage system further includes a first pump and a second pump. In the first sub-state and the third sub-state, the first pump is connected to the bottom of the water storage tank and the second port of the heating network first station, respectively, so that water in the bottom of the water storage tank flows into the heating network first station through the first pump. In the second sub-state and the fourth sub-state, both ends of the second pump are connected to the top of the water storage tank and the heating pipe, respectively, so that water in the water storage tank flows into the heating pipe through the second pump.

[0015] In some embodiments, the temperature of the water storage tank is not greater than 95°C.

[0016] In some embodiments, the electric boiler thermal storage system further includes a connecting member, the two ends of which are respectively connected to one end of the first channel and the first outlet of the heating network first station. During the peak heating period and the beginning and end of the heating period, the connecting member is connected so that the thermal storage component is connected to the heating network first station through the connecting member. During the non-heating season or non-peak period, the connecting member is disconnected so that the thermal storage component is disconnected from the heating network first station through the connecting member.

[0017] According to the power grid peak shaving method of the present invention, the electric boiler thermal storage system described in any of the above embodiments includes: S1: When the thermal power plant needs peak shaving, the thermal power plant reduces its own electrical load and gradually closes the low-pressure connection of the thermal power plant to control the stability of the first-station water supply temperature by valve control; S2: When the low-pressure connection valve of the thermal power plant is closed to the minimum and the water supply temperature cannot be stabilized, the thermal storage component of the electric boiler thermal storage system is turned on to increase the water supply temperature; S3: When the thermal power plant needs further deep peak shaving, the load of the thermal power plant is kept unchanged and continuously increased. The load of the electrode boiler in the thermal power plant will be further reduced because the electricity consumed by the electrode boiler is the plant's own electricity. At the same time, the heat exchange efficiency of the heat storage component will be adjusted according to the change of the water supply temperature of the first station of the heating network to maintain the stability of the water supply temperature of the first station of the heating network; S4: As the peak shaving depth continues to increase, when the water supply temperature of the first station of the heating network is stable and the water supply temperature of the first station of the heating network is higher than the preset value, some of the hot water in the heat storage component will flow into the water storage tank to store the heat in the electric boiler heat storage system. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the electric boiler thermal storage system according to an embodiment of the present invention.

[0019] Figure label:

[0020] 100 electric boiler thermal storage system;

[0021] Import header 001; Export header 002; First electric thermal storage bypass valve 101; Second electric thermal storage bypass valve 102; First thermal storage component inlet valve 103; First thermal storage component outlet valve 104; Second thermal storage component inlet valve 105; Second thermal storage component outlet valve 106; First auxiliary heat storage valve 113; Second auxiliary heat storage valve 114;

[0022] Valves 107-112, 201-208, 305, 309;

[0023] First main aerator hotspot 301; First main storage hotspot 302; Second main storage hotspot 303; Second main aerator hotspot 304; First pump outlet valve 306; First pump 307; First pump inlet valve 308; Second pump outlet valve 310; Second pump 311; Second pump inlet valve 312;

[0024] First electric thermal storage device 401; Second electric thermal storage device 402; Third electric thermal storage device 403; Fourth electric thermal storage device 404; First detection component 501; Second detection component 502;

[0025] Water storage tank 601; First heating network first station 6; Second heating network first station 7; Heating pipe 8; Return water pipe 9. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0027] The electric boiler thermal storage system according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, the electric boiler thermal storage system 100 according to an embodiment of the present invention includes a thermal power plant (not shown in the figure), a thermal storage component 4, and a water storage tank 601.

[0029] A thermal power plant is used to generate electricity and heat. The thermal power plant includes a heating network primary station with a first inlet and a second inlet. The first inlet of the heating network primary station is adapted to be connected to a heating pipe 8 so that hot water flowing out of the heating network primary station flows into the heating pipe 8 to provide heat energy to users. Alternatively, the second inlet of the heating network primary station is adapted to be connected to a return water pipe 9 so that return water in the return water pipe 9 flows into the heating network primary station to heat the return water.

[0030] Specifically, such as Figure 1As shown, the thermal power plant provides electricity and heat to users. The first outlet is the outlet of the first heating station and is connected to the inlet of the heating pipe 8 so that the hot water (heating network supply water) generated by the first heating station flows into the heating pipe 8 and is then supplied to users through the heating pipe 8 so that users can obtain heat energy. The second outlet is the outlet of the first heating station and is connected to the outlet of the return water pipe 9 so that the water (heating network return water) in the return water pipe 9 flows into the first heating station to heat the heat network return water.

[0031] The heat storage component 4 has a first channel (not shown in the figure) and a second channel (not shown in the figure) that are independent of each other and can exchange heat. When the electric boiler heat storage system 100 is in the non-heating season or non-peak period, one end of the first channel is disconnected from the first port of the heating network first station so that the heating network first station can provide heat energy to users.

[0032] Specifically, during the non-heating season or non-peak period, when the electric boiler heat storage system 100 is in operation, the heat storage component 4 and the water storage tank 601 are not working, and all the water at the first station of the heating network flows to users to provide them with heat energy.

[0033] During peak-shaving periods, one end of the first channel of the electric boiler thermal storage system 100 is connected to the first outlet of the heating network's primary station, allowing hot water flowing out of the primary station to enter the first channel. One end of the second channel is adapted to connect to the electrode boiler, allowing steam generated by the electrode boiler to flow into the second channel to heat the hot water in the first channel. Specifically, as follows... Figure 1 As shown, the heat storage component 4 is a plate heat exchanger. The inlet of the first channel is connected to the first outlet of the first station of the heating network, so that part of the hot water flowing out of the first station of the heating network flows into the first channel. The inlet of the second channel is connected to the electrode boiler, so that the steam or hot water generated by the electrode boiler flows into the second channel, so that the first channel and the second channel exchange heat, thereby further increasing the temperature of the hot water in the first channel and decreasing the temperature of the steam or hot water in the second channel.

[0034] The electric boiler thermal storage system 100 includes a first state and a second state. In the first state, the other end of the first channel is connected to the heating pipe 8 so that heated hot water flows into the heating pipe 8 to provide heat energy to the user. In the second state, the other end of the first channel is connected to both the heating pipe 8 and the water storage tank 601 so that a portion of the hot water flowing out of the first channel flows into the heating pipe 8 and the other portion flows into the water storage tank 601. Specifically, as shown... Figure 1As shown, in the first state, the outlet of the first channel is connected to the heating pipe 8, so that the hot water heated by the heat storage component 4 flows into the heating pipe 8 to increase the heating temperature of the heating pipe 8. In the second state, the outlet of the first channel is connected to the heating pipe 8 and the inlet of the water storage tank 601 respectively, so that the heated water in the heat exchange tube is divided into two parts, one part flows into the heating pipe 8 to increase the heating temperature in the heating pipe 8, and the other part flows into the water storage tank 601 to store the excess hot water.

[0035] A thermal power plant generates both electrical and thermal energy. The thermal energy is transferred to an electric boiler thermal storage system to provide heat to users, while the electrical energy is transferred to a thermal power unit to provide electricity to users. When the thermal power plant receives an instruction to adjust peak load, it first reduces its own electrical load and gradually closes the medium and low pressure connecting valves in the electric boiler thermal storage system 100 to stabilize the water supply temperature at the first station of the heating network. As the electrical load decreases, when the medium and low pressure connecting valves are closed to their minimum and the water supply temperature cannot be stabilized (or during peak heating periods), the electric boiler thermal storage system 100 enters its first state. Start the heat storage component 4, and then continue to reduce the electrical load on the thermal power plant. Gradually increase the output of the heat storage component 4 according to the changes in the water supply temperature of the first station of the heating network to maintain the stability of the water supply temperature of the first station of the heating network. As the peak shaving depth increases, if there is still a margin in the output of the heat storage component 4 when the water supply temperature of the first station is stable (e.g., at the beginning and end of the heating period), the output of the heat storage component 4 can also be increased. The electric boiler heat storage system 100 is in the second state. At this time, the excess heat generated can flow into the water storage tank 601 and be stored in the water storage tank 601.

[0036] The electric boiler thermal storage system 100 of this embodiment includes a heating network primary station, a thermal storage component 4, and a water storage tank 601. The thermal storage component 4 can process the hot water flowing from the heating network primary station to increase the heat energy supplied to users. When the power plant needs peak shaving, it can operate under low electrical load conditions, and the thermal storage component 4 ensures the heating capacity of the electric boiler thermal storage system 100, thereby enhancing the power plant's peak shaving capability, reducing its operating costs, and maximizing its participation in peak shaving to obtain peak shaving service revenue. Furthermore, the excess heat energy generated by the thermal storage component 4 can be stored in the water storage tank 601, avoiding energy waste and reducing the operating costs of the electric boiler thermal storage system 100.

[0037] In some embodiments, there are multiple heat storage components 4, and at least one of the multiple heat storage components 4 is connected to the first outlet of the heating network's primary station, so that hot water flowing out of the primary station flows into at least one of the multiple heat storage components 4. During peak heating periods, at least one of the heat storage components 4 is connected to the heating pipe 8, and during the beginning and end of the heating period, at least one of the heat storage components 4 is connected to both the heating pipe 8 and the water storage tank 601. Specifically, as... Figure 1As shown, the heat storage components 4 are spaced apart in the left-right direction. The inlet of the first channel of each heat storage component 4 is connected to the first port of the heating network's primary station. The heat storage components 4 can be activated according to the actual situation. For example, hot water flowing out of the heating network's primary station can flow into one or more of the heat storage components 4, making one or more of the heat storage components 4 work. Alternatively, hot water flowing out of the heating network's primary station can flow into each heat storage component 4, making each heat storage component 4 work. In other words, the heat storage components 4 are connected to the heating network's primary station in parallel. This makes the operation mode of the heat storage components 4 flexible and changeable. The heat storage components 4 can be activated according to the actual working conditions, improving the working efficiency of the heat storage components 4, avoiding energy waste, and reducing the heating cost of the electric boiler heat storage system 100.

[0038] In some embodiments, the primary heating network station includes a first primary heating network station 6 and a second primary heating network station 7. Both the first primary heating network station 6 and the second primary heating network station 7 have a first outlet and a second outlet. A portion of a plurality of heat storage components 4 are respectively connected to the first outlet of the first primary heating network station 6 and the heating pipe 8, so that a portion of the plurality of heat storage components 4 heats the hot water flowing out of the first primary heating network station 6. Another portion of the plurality of heat storage components 4 are respectively connected to the first outlet of the second primary heating network station 7 and the heating pipe 8, so that another portion of the plurality of heat storage components 4 heats the hot water flowing out of the second primary heating network station 7. Specifically, as... Figure 1 As shown, the heat storage component 4 can heat the water flowing out of the first heating network's first station 6 or the second heating network's first station 7, depending on the actual situation. For example, the heat storage component 4 has four components (such as...). Figure 1The four components shown are a first heat storage component 401, a second heat storage component 402, a third heat storage component 403, and a fourth heat storage component 404. The first heating network head station 6 is connected to the first heat storage component 401, and hot water flowing out of the first heating network head station 6 flows into the first heat storage component 401. The second heat storage components 402, 403, and 404 are all connected to the second heating network head station 7, so that hot water flowing out of the second heating network head station 7 flows into the second heat storage components 402, 403, and 404. This allows the first heat storage component 401 to heat the water flowing out of the first heating network's first station 6, and the second, third, and fourth heat storage components 402, 403, and 404 to heat the water flowing out of the second heating network's first station 7. Alternatively, the first heating network's first station 6 can be connected to the first and second heat storage components 401 and 402, allowing the hot water flowing out of the first heating network's first station 6 to flow into the first and second heat storage components 401 and 402. The third and fourth heat storage components 403 and 404 can both be connected to the second heating network's first station 7, allowing the hot water flowing out of the second heating network's first station 7 to... The water flows into the third heat storage component 403 and the fourth heat storage component 404, thereby allowing the first heat storage component 401 and the second heat storage component 402 to heat the water flowing out of the first heating network first station 6, and the third heat storage component 403 and the fourth heat storage component 404 to heat the water flowing out of the second heating network first station 7. Alternatively, the first heat storage component 401, the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404 can all be connected to the first heating network first station 6, while the second heating network first station 7 is no longer connected to the heat storage component 404, allowing the water flowing out of the first heating network first station 6 to flow into the third heat storage component 403 and the fourth heat storage component 404. The first heat storage component 401, the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404 heat the water flowing out of the first heating network first station 6. Thus, the multiple heat storage components 4 can simultaneously supply heat to the first heating network first station 6 or the second heating network first station 7 individually, or the multiple heat storage components 4 can be flexibly grouped to supply heat to the first heating network first station 6 and the second heating network first station 7 individually, thus optimizing the heat distribution of the multiple heat storage components 4.

[0039] In some embodiments, the electric boiler thermal storage system 100 further includes a detection component, the two ends of which are respectively connected to the thermal storage component 4 and the heating pipe 8, so that the detection component can detect the flow rate of hot water flowing into the heating pipe 8 through the thermal storage component 4. Specifically, as Figure 1As shown, the detection component is a flow sensor. The inlet of the detection component is connected to the outlet of the first channel of the heat storage component 4, and the outlet of the detection component is connected to the heating pipe 8, so that the hot water in the first channel of the heat storage component 4 flows into the heating pipe 8 through the detection component to increase the temperature of the hot water in the heating pipe 8 and thus increase the heating supply to the user. The detection component can be used to detect the flow rate of the hot water flowing into the heating pipe 8 from the heat storage component 4, thereby detecting the temperature of the hot water in the heating pipe 8 through the flow rate.

[0040] In some embodiments, the detection component includes a first detection component 501 and a second detection component 502. The two ends of the first detection component 501 are respectively connected to the heating pipes 8 of the heat storage component 4 and the first heating network first station 6, and the two ends of the second detection component 502 are respectively connected to the heating pipes 8 of the heat storage component 4 and the second heating network first station 7. Thus, the first detection component 501 detects the flow rate of hot water flowing from the heat storage component 4 into the heating pipe 8 of the first heating network first station 6, and the second detection component 502 detects the flow rate of hot water flowing from the heat storage component 4 into the heating pipe 8 of the second heating network first station 7.

[0041] In some embodiments, the temperature of the water storage tank 601 does not exceed 95°C. Specifically, when the electric boiler heat storage system 100 is working, the water storage tank 601 is always full of water. The water storage tank 601 has a third inlet and a fourth inlet. The third inlet is located near the top of the water storage tank 601, and the fourth inlet is located near the bottom of the water storage tank 601. Since the density of hot water is lower than that of cold water, the water temperature at the bottom of the water storage tank 601 is lower than that at the top of the water storage tank 601. In other words, the cold water in the water storage tank 601 is located at the bottom of the water storage tank 601, and the hot water in the water storage tank 601 is located at the top of the water storage tank 601. The temperature inside the water storage tank 601 does not exceed 95°C, which can prevent the risk of vaporization inside the water storage tank 601 and improve the safety performance of the water storage tank 601.

[0042] In some embodiments, the first state includes a first sub-state and a second sub-state. During the peak-shaving period of the heating season, the electric boiler thermal storage system 100 is in the first sub-state. The top of the water storage tank 601 is connected to the first inlet of the heating network's primary station so that excess hot water generated by the primary station flows into the water storage tank 601. The bottom of the water storage tank 601 is connected to the second inlet of the heating network's primary station so that water in the water storage tank 601 flows into the heating network's primary station. Specifically, as shown in... Figure 1As shown, during the peak-shaving period of the heating season, when the heat storage component 4 is operating and the heating network water supply temperature is ≥95℃, in the first sub-state, the third port of the water storage tank 601 is connected to the first port of the heating network first station, and the fourth port of the water storage tank 601 is connected to the second port of the heating network first station. This allows the excess hot water generated after heat exchange by the heat storage component 4 to be stored in the water storage tank 601 to store the excess heat generated by the heat storage component 4. The cold water at the bottom of the water storage tank 601 flows into the return water pipe 9 to replenish the heating network return water, thus keeping the water in the water storage tank 601 balanced.

[0043] In some embodiments, during the off-peak period of peak heating, the electric boiler thermal storage system 100 is in a second sub-state, with the top of the water storage tank 601 connected to the heating pipe 8 so that water in the water storage tank 601 flows into the heating pipe 8, and the bottom of the water storage tank 601 connected to the return water pipe 9 so that water in the return water pipe 9 flows into the water storage tank 601. Specifically, as Figure 1 As shown, in the second sub-state, the third port of the water storage tank 601 is connected to the heating pipe 8, so that the hot water in the water storage tank 601 flows into the heating pipe 8 to replenish the heating network return water in the heating pipe 8. The fourth port of the water storage tank 601 is connected to the return water pipe 9, so that the water in the return water pipe 9 flows into the water storage tank 601 to replenish the water storage tank 601 to ensure the water balance in the water storage tank 601.

[0044] In some embodiments, the second state includes a third sub-state and a fourth sub-state. During the peak-shaving period at the beginning and end of the heating season, the electric boiler thermal storage system 100 is in the third sub-state. The top of the water storage tank 601 is connected to the other end of the first channel of the thermal storage component 4, so that excess hot water in the first channel of the thermal storage component 4 flows into the water storage tank 601. The bottom of the water storage tank 601 is connected to the second outlet of the heating network's first station, so that water in the water storage tank 601 flows into the heating network's first station. Specifically, as... Figure 1 As shown, in the third sub-state, during the peak-shaving period at the beginning and end of the heating season, when the heat storage component 4 is running and the heating network water supply temperature is less than 95℃, the third port of the water storage tank 601 is connected to the outlet of the first channel of the heat storage component 4, and the fourth port of the water storage tank 601 is connected to the second port of the first station of the heating network. This allows the excess hot water generated after heat exchange by the heat storage component 4 to be stored in the water storage tank 601 to store the excess heat generated by the heat storage component 4. The cold water at the bottom of the water storage tank 601 flows into the return water pipe 9 to replenish the heating network return water, thus keeping the water in the water storage tank 601 balanced.

[0045] In some embodiments, during the non-peak-shaving period at the beginning and end of the heating season, the electric boiler thermal storage system 100 is in a fourth sub-state, with the top of the water storage tank 601 connected to the heating pipe 8 so that water in the water storage tank 601 flows into the heating pipe 8, and the bottom of the water storage tank 601 connected to the return water pipe 9 so that water in the return water pipe 9 flows into the water storage tank 601. Specifically, as Figure 1As shown, in the fourth sub-state, the third port of the water storage tank 601 is connected to the heating pipe 8, so that the hot water in the water storage tank 601 flows into the heating pipe 8 to replenish the heating network return water in the heating pipe 8. The fourth port of the water storage tank 601 is connected to the return water pipe 9, so that the water in the return water pipe 9 flows into the water storage tank 601 to replenish the water storage tank 601 to ensure the water balance in the water storage tank 601.

[0046] In some embodiments, the electric boiler thermal storage system 100 further includes a first pump 307 and a second pump 311. In the first sub-state and the third sub-state, the first pump 307 is connected to the bottom of the water storage tank 601 and the second port of the heating network first station, respectively, so that water in the bottom of the water storage tank 601 flows into the heating network first station through the first pump 307. In the second sub-state and the fourth sub-state, the two ends of the second pump 311 are connected to the top of the water storage tank 601 and the heating pipe 8, respectively, so that water in the water storage tank 601 flows into the heating pipe 8 through the second pump 311.

[0047] Specifically, such as Figure 1 As shown, both the first pump 307 and the second pump 311 are water pumps. In the first and third sub-states, the inlet of the first water pump is connected to the fourth port of the water storage tank 601, and the outlet of the first water pump is connected to the second port of the heating network's primary station. Thus, water from the bottom of the water storage tank 601 flows into the heating network's primary station through the fourth port and the first pump 307. Simultaneously, water after heat exchange by the heat storage component 4 or excess hot water generated by the heating network's primary station is discharged into the water storage tank 601 through the third port. In the second and fourth sub-states, the inlet of the second pump 311 is connected to the third port of the water storage tank 601, and the outlet of the second pump 311 is connected to the heating pipe 8. Therefore, Water from the storage tank 601 is pumped into the heating pipe 8 by the second pump 311 to supplement the heating pipe 8 with heat energy. At the same time, some water in the return water pipe 9 automatically flows into the storage tank 601. Thus, the first pump 307 and the second pump 311 provide kinetic energy for the flow of water in the electric boiler heat storage system 100. Since the water temperature at the bottom of the storage tank 601 is low, the first pump 307 can be a low-temperature water pump and there is no need to use a high-temperature water pump. Therefore, the investment cost of the electric boiler heat storage system 100 is low. At the same time, according to the heat transfer characteristics of the heat exchanger, the lower return water temperature can maximize the heat exchange capacity of the first station and avoid resource waste.

[0048] In some embodiments, the electric boiler thermal storage system 100 further includes a connecting member, the two ends of which are respectively connected to one end of the first channel and the first port of the heating network's primary station. During peak heating periods and the beginning and end of the heating season, the connecting member is connected so that the thermal storage component 4 is connected to the heating network's primary station through the connecting member. During non-heating seasons or non-peak periods, the connecting member is disconnected so that the thermal storage component 4 is disconnected from the heating network's primary station through the connecting member. Specifically, as shown... Figure 1As shown, the connecting element can be valve 302. The inlet of the connecting element is connected to the first port of the heating network's primary station, and the outlet of the connecting element is connected to the inlet of the first channel of the heat storage component 4. Thus, the connection between the heating network's primary station and the heat storage component 4 is controlled through the connecting element. During peak heating periods and the beginning and end of the heating period, when the heating network's primary station is insufficient in heating or when the power grid is adjusting its peak load, the connecting element and the heat storage component 4 are opened, allowing some of the hot water generated by the heating network's primary station to flow into the heat storage component 4 through the connecting element to heat the hot water. During non-heating seasons or non-peak periods, or when the heating network's primary station is sufficient in heating, the connecting element and the heat storage component 4 are closed, disconnecting the heating network's primary station and the heat storage component 4 to prevent the hot water generated by the heating network's primary station from flowing into the heat storage component 4.

[0049] like Figure 1 As shown, the power grid peak-shaving method according to an embodiment of the present invention, utilizing any one of the electric boiler thermal storage systems 100 in the above embodiments, includes:

[0050] S1: When the thermal power plant needs to regulate peak load, the thermal power plant reduces its own electrical load and gradually shuts off the low-pressure connection between the thermal power plant and the first station to control the water supply temperature of the valve to stabilize.

[0051] S2: When the thermal power plant needs further deep peak shaving, the load of the thermal power plant is kept constant, and the load of the electrode boiler of the thermal power plant is continuously increased. Since the electricity consumed by the electrode boiler is the plant's auxiliary power, the amount of electricity fed into the grid will be reduced further. At the same time, the heat exchange efficiency of the heat storage component 4 is adjusted according to the change of the water supply temperature at the first station of the heating network to maintain the stability of the water supply temperature at the first station of the heating network.

[0052] S3: Continuously reduce the electrical load on the thermal power plant, and gradually increase the heat exchange efficiency of the heat storage component 4 according to the changes in the water supply temperature of the first station of the heating network in order to maintain the stability of the water supply temperature of the first station of the heating network.

[0053] S4: As the peak shaving depth continues to increase, when the water supply temperature at the first heating station is stable and the water supply temperature at the first heating station is higher than the preset value, some of the hot water in the heat storage component 4 will flow into the storage tank to store the heat in the electric boiler heat storage system 100.

[0054] Therefore, the power grid peak-shaving method according to the embodiments of the present invention has the advantages of simple steps, strong peak-shaving capacity, and low operating cost.

[0055] The following is based on Figure 1 The electric boiler thermal storage system 100 of this embodiment of the invention is described in detail.

[0056] like Figure 1As shown, the electric boiler thermal storage system 100 includes the first heating network station 6, the second heating network station 7, the first thermal storage component 401, the second thermal storage component 402, the third thermal storage component 403, the fourth thermal storage component 404, the water storage tank 601, the first pump 307, the second pump 311, and a series of valve combinations, pipelines, etc.

[0057] The inlet header 001 and outlet header 002 of the electric boiler thermal storage system 100 are connected in parallel with four thermal storage components 401-404 to form thermal storage component 4. Each plate heat exchanger's secondary side is connected to the inlet main pipe 001 and the outlet main pipe 002 via inlet and outlet branch pipes, respectively. Valve 205 is installed on the inlet branch pipe of the first heat storage component 401, and valve 201 is installed on the outlet branch pipe of the first heat storage component 401. Valve 206 is installed on the inlet branch pipe of the second heat storage component 402, and valve 202 is installed on the outlet branch pipe of the second heat storage component 402. Valve 207 is installed on the inlet branch pipe of the third heat storage component 403, and valve 203 is installed on the outlet branch pipe of the third heat storage component 403. Valve 208 is installed on the inlet branch pipe of the fourth heat storage component 404, and valve 204 is installed on the outlet branch pipe of the fourth heat storage component 404. Valves 201-208 are used for the maintenance of the first heat storage component 401, the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404. Each heat storage component 4 is supplied with a heat source by an electrode boiler.

[0058] The water supply from the first heating network's first station 6 connects to one end of the inlet header 001 via the inlet gate 103 of the first thermal storage component, and then connects to the outlet gate 104 of the first thermal storage component to supply heat to users. One end of the first electric thermal storage bypass gate 101 connects to the inlet gate 103 of the first thermal storage component, and the other end connects to the outlet gate 104 of the first thermal storage component. Hot water from the outlet of the first heating network's first station 6 can then be directly supplied to users via the first electric thermal storage bypass gate 101. The water supply from the second heating network's first station 7 connects to the other end of the inlet header 001 via the inlet gate 105 of the second thermal storage component, and then connects to the outlet gate 106 of the second thermal storage component to supply heat to users after passing through the thermal storage component 4. One end of the second electric thermal storage bypass gate 102 connects to the inlet gate 105 of the second thermal storage component, and the other end connects to the outlet gate 106 of the second thermal storage component. Hot water from the outlet of the second heating network's first station 7 can then be directly supplied to users via the second electric thermal storage bypass gate 102. The first detection component 501 and the second detection component 502 are respectively installed after the inlet gate 103 of the first heat storage component and the inlet gate 105 of the second heat storage component to measure the water flow rate.

[0059] One water storage tank 601 is installed, and the water temperature inside the tank must not exceed 95℃. The water storage tank 601 is connected in parallel to the first heating network station 6 and the second heating network station 7 via a water supply pipe 313 and a return water pipe 314. A second pump 311 is installed on the water supply pipe 313, along with an inlet valve 312, an outlet valve 310, and a water supply bypass valve 309. A first pump 307 is installed on the return water pipe 314, along with an inlet valve 308, an outlet valve 306, and a return water bypass valve 305. One end of the water supply pipe 313 is connected to the upper part of the water storage tank 601, and the other end is connected to four locations: via the first main water storage pipe 302, it connects to the first heating network's first station 6 for water supply; via the second main water storage pipe 303, it connects to the second heating network's first station 7 for water supply; via the first auxiliary water storage pipe 113, it connects to one end of the outlet header pipe 002; and via the second auxiliary water storage pipe 114, it connects to the other end of the outlet header pipe 002. One end of the return water pipe 314 is connected to the lower part of the water storage tank 601, and the other end is connected to two locations: via the first main outlet water storage pipe 301, it connects to the return water pipe 9 of the first heating network's first station 6; and via the second main outlet water storage pipe 304, it connects to the return water pipe 9 of the second heating network's first station 7.

[0060] The first heat storage component 401, the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404 can achieve five operating modes by operating the connecting gates on the inlet header 001 and the inlet header 002: all three heat storage components 401, 402, 403, and 404 are connected in series to the first heating network head station 6; all three heat storage components 401, 402, 403, and 404 are connected in parallel to the second heating network head station 7; one heat storage component is connected in series to the first heating network head station 6 and three heat storage components are connected in series to the second heating network head station 7; two heat storage components are connected in parallel to the first heating network head station 6 and two heat storage components are connected in series to the second heating network head station 7; and three heat storage components are connected in parallel to the first heating network head station 6 and one heat storage component is connected in series to the second heating network head station 7. Valves 105, 106, 113, and 114 are closed, while valves 103, 104, 107, 108, 109, 110, 111, and 112 are opened. The first heat storage component 401, the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404 are all connected in series to the first heating network's first station 6. Valves 103, 104, 105, 106, 108, 109, 111, and 112 are opened, while valves 107 and 110 are closed. The first heat storage component 401 is connected in series to the first heating network's first station 6, and the second heat storage component 402, the third heat storage component 403, and the fourth heat storage component 404 are connected in series to the second heating network's first station 7. Valves 103, 104, 105, 106, 107, 110, 109, and 112 are opened. When valves 108 and 111 are closed, the first heat storage component 401 and the second heat storage component 402 are connected in series to the first heating network first station 6, and the third heat storage component 403 and the fourth heat storage component 404 are connected in series to the second heating network first station 7; when valves 103, 104, 105, 106, 107, 110, 108, and 111 are opened, and valves 109 and 112 are closed, the first heat storage component 401, the second heat storage component 402, and the third heat storage component 403 are connected in series to the first heating network first station 6, and the fourth heat storage component 404 is connected in series to the second heating network first station 7; when valves 105, 106, 107, 110, 108, 111, 109, and 112 are opened, and valves 103, 104, and 113 are closed, all heat storage components 4 are connected in series to the second heating network first station 7.

[0061] During the peak-shaving period at the beginning and end of the heating season, when the heat storage component 4 is running and the heating network supply water temperature is less than 95℃, valves 113, 114, 308, and 309 can be opened, the first pump 307 can be started, and valves 306 and 301 can be opened to store the excess hot water from the outlet of the heat storage component 4 in the storage tank 601. The cold water at the bottom of the storage tank 601 will be discharged to the heating network return water. During the non-peak-shaving period at the beginning and end of the heating season, valves 301, 305, and 312 can be opened, the second pump 311 and 311 can be started, and valves 310, 113, and 114 can be opened to inject the stored hot water into the heating pipe 8 and fill the storage tank 601 with the heating network return water.

[0062] During peak-shaving periods in extremely cold heating seasons, when the heat storage component 4 is operating and the heating network supply water temperature is ≥95℃, valves 113 and 114 can be closed, and valves 302, 303, 308, and 309 can be opened. At the same time, the first pump 307 can be started, and valves 306 and 301 can be opened to store excess hot water from the heating network supply in the storage tank 601. The cold water at the bottom of the tank 601 will be discharged to the heating network return water. During non-peak-shaving periods in extremely cold heating seasons, valves 301, 305, and 312 can be opened, the second pump 311 and 311 can be started, and valves 310, 302, and 303 can be opened to inject the stored hot water into heating pipes 8 and fill the storage tank 601 with heating network return water.

[0063] Therefore, the electric boiler thermal storage system 100 of the present invention has the following advantages:

[0064] A series of connecting gates (valves) are installed on the heat storage component 4, the inlet header 001 and the outlet header 002. By using different switch combinations, each heat storage component 4 can be connected in series with the first heating network first station 6 or with the second heating network first station 8 to achieve optimized distribution of heat in different regions.

[0065] An open-type water storage tank is installed in the electric boiler heat storage system 100. The water temperature in the tank must not exceed 95℃. The water storage tank is connected in parallel with the first heating network station 6 and the second heating network station 7, respectively. When the electric boiler heat storage system 100 has excess heat, hot water from the supply water can be stored in the tank. When the heat is insufficient, the heat in the stored water tank can be released. The water storage tank can also be connected in series with the heat storage component 4 to store the hot water from the outlet of the water storage tank 601, releasing heat when needed.

[0066] During peak-shaving periods, when the heating network has excess heat, if it is the beginning or end of the heating season and the outlet temperature of the heat storage component is less than 95℃, a portion of the hot water from the outlet of the heat storage component can be stored in the water storage tank 601; if it is the extremely cold heating season and the outlet temperature of the heat storage component is greater than 95℃, a portion of the hot water from the outlet of the first station of the heating network can be stored in the water storage tank 601.

[0067] In summary, the method of using thermal storage components to participate in grid peak shaving services has low retrofit and investment costs, flexible operation modes, and can maximize participation in peak shaving to obtain peak shaving service benefits. At the same time, it optimizes the allocation of heat from the thermal storage components, saving energy consumption.

[0068] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0072] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0073] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An electric boiler heat accumulation system, characterized in that, include: A thermal power plant for generating electricity and heat, the thermal power plant including a heating network head station having a first outlet and a second outlet, the first outlet of the heating network head station being adapted to be connected to a heating pipe so that hot water flowing out of the heating network head station flows into the heating pipe to provide heat to users, or the second outlet of the heating network head station being adapted to be connected to a return water pipe so that return water in the return water pipe flows into the heating network head station to heat the return water; The heat storage component and the water storage tank, wherein the heat storage component has a first channel and a second channel that are independent of each other and can exchange heat, and when the electric boiler heat storage system is in the non-heating season or non-peak period, one end of the first channel is disconnected from the first port of the heating network first station so that the heating network first station can provide heat energy to users; During peak-shaving periods, one end of the first channel is connected to the first outlet of the heating network's primary station, allowing some of the hot water flowing out of the primary station to enter the first channel. One end of the second channel is adapted to connect to the electric boiler, allowing steam generated by the electric boiler to flow into the second channel to heat the hot water in the first channel. The electric boiler heat storage system has a first state and a second state during peak shaving periods. In the first state, the other end of the first channel is connected to the heating pipe so that the heated hot water flows into the heating pipe to provide heat energy to the user. In the second state, the other end of the first channel is connected to the heating pipe and the water storage tank respectively so that a portion of the hot water flowing out of the first channel flows into the heating pipe and another portion of the hot water flowing out of the first channel flows into the water storage tank.

2. The electric boiler thermal storage system according to claim 1, characterized in that, The heat storage components are multiple, and at least one of the multiple heat storage components is connected to the first outlet of the heating network first station so that the hot water flowing out of the heating network first station flows into at least one of the multiple heat storage components. During the peak heating period, at least one of the heat storage components is connected to the heating pipe. During the beginning and end of the heating period, at least one of the heat storage components is connected to the heating pipe and the water storage tank respectively.

3. The electric boiler thermal storage system according to claim 2, characterized in that, The heating network's primary stations include a first heating network primary station and a second heating network primary station. Both the first and second heating network primary stations have a first outlet and a second outlet. A portion of the plurality of heat storage components is connected to the first outlet of the first heating network primary station and the heating pipe, respectively, so that a portion of the plurality of heat storage components heats the hot water flowing out of the first heating network primary station. Another portion of the plurality of heat storage components is connected to the first inlet of the second heating network first station and the heating pipe, so that the other portion of the plurality of heat storage components heats the hot water flowing out of the second heating network first station.

4. The electric boiler thermal storage system according to claim 1, characterized in that, It also includes a detection component, the two ends of which are connected to the heat storage component and the heating pipe, respectively, so that the detection component can detect the flow rate of hot water flowing into the heating pipe through the heat storage component.

5. The electric boiler thermal storage system according to claim 1, characterized in that, The first state includes a first sub-state and a second sub-state. During the peak-shaving period of the heating season, the electric boiler thermal storage system is in the first sub-state. The top of the water storage tank is connected to the first inlet of the heating network's primary station so that excess hot water generated by the primary station flows into the water storage tank. The bottom of the water storage tank is connected to the second inlet of the heating network's primary station so that water in the water storage tank flows into the heating network's primary station. During the off-peak period of the heating season, when the electric boiler heat storage system is in the second sub-state, the top of the water storage tank is connected to the heating pipe so that water in the water storage tank flows into the heating pipe, and the bottom of the water storage tank is connected to the return water pipe so that water in the return water pipe flows into the water storage tank.

6. The electric boiler thermal storage system according to claim 5, characterized in that, The second state includes a third sub-state and a fourth sub-state. During the peak-shaving period at the beginning and end of the heating season, the electric boiler thermal storage system is in the third sub-state. The top of the water storage tank is connected to the other end of the first channel of the thermal storage component, so that excess hot water in the first channel of the thermal storage component flows into the water storage tank. The bottom of the water storage tank is connected to the second outlet of the heating network's primary station, so that water in the water storage tank flows into the heating network's primary station. During the non-peak-shaving period at the beginning and end of the heating season, the electric boiler thermal storage system is in the fourth sub-state. The top of the water storage tank is connected to the heating pipe so that water in the water storage tank flows into the heating pipe, and the bottom of the water storage tank is connected to the return water pipe so that water in the return water pipe flows into the water storage tank.

7. The electric boiler thermal storage system according to claim 6, characterized in that, It also includes a first pump and a second pump. In the first sub-state and the third sub-state, the first pump is connected to the bottom of the water storage tank and the second inlet of the heating network first station, respectively, so that water in the bottom of the water storage tank flows into the heating network first station through the first pump. In the second sub-state and the fourth sub-state, the two ends of the second pump are respectively connected to the top of the water storage tank and the heating pipe, so that the water in the water storage tank flows into the heating pipe through the second pump.

8. The electric boiler thermal storage system according to any one of claims 1-7, characterized in that, The temperature of the water storage tank shall not exceed 95°C.

9. The electric boiler thermal storage system according to claim 1, characterized in that, It also includes a connecting component, the two ends of which are respectively connected to one end of the first channel and the first outlet of the first heating network station. During peak heating season and the beginning and end of the heating season, the connecting piece is connected so that the heat storage component can be connected to the first station of the heating network through the connecting piece. During non-heating season or non-peak period, the connecting piece is disconnected so that the heat storage component can be disconnected from the first station of the heating network through the connecting piece.

10. A power grid peak-shaving method, utilizing the electric boiler thermal storage system described in any one of claims 1-9, characterized in that, include: S1: When the thermal power plant needs to regulate peak load, the thermal power plant reduces its own electrical load and gradually closes the low-pressure connecting valves in the thermal power plant to control the water supply temperature of the first station to stabilize. S2: When the low-pressure connecting valve in the thermal power plant is closed to the minimum and the water supply temperature cannot be stabilized, the heat storage component of the electric boiler heat storage system is turned on to increase the water supply temperature. S3: When the thermal power plant needs to further reduce peak load, the load of the thermal power plant is kept constant, and the load of the electric boiler of the thermal power plant is continuously increased. Since the electricity consumed by the electric boiler is the electricity used by the thermal power plant, the electricity fed into the grid will be reduced further. At the same time, the heat exchange efficiency of the heat storage component is adjusted according to the change of the water supply temperature of the first station of the heating network to maintain the stability of the water supply temperature of the first station of the heating network. S4: As the peak shaving depth continues to increase, when the water supply temperature at the first station of the heating network is stable and the water supply temperature at the first station of the heating network is higher than the preset value, some of the hot water in the heat storage component flows into the water storage tank to store the heat in the electric boiler heat storage system.

Images