Coupling system for assisting absorption of new energy and operation method thereof

Abstract

The invention discloses a coupling system for assisting in absorbing new energy and an operation method thereof, and belongs to the technical field of new energy power generation. The coupling system for assisting in absorbing the new energy comprises a fused salt system, a wind / light generator set and a coal-fired unit, the wind / light generator set and the coal-fired unit are connected with a public power grid, and the fused salt system is in coupling connection with the coal-fired unit through a fused salt heat exchanger; a power supply device connected with the power input end of the fused salt electric heater is arranged at the power output end of the wind / light generator set, by controlling the low-temperature fused salt adjusting valve and the high-temperature fused salt adjusting valve, redundant electric energy of wind and light power generation is used for heating fused salt and storing heat energy, and the heat energy is released at the load peak or when the power generation output of the wind / light generator set is insufficient. Therefore, the flexibility of the coal-fired unit is improved, and efficient and stable operation of a power system is realized. Meanwhile, by means of the heat storage function of the fused salt system, fluctuation of wind and light power generation is relieved, more stable power generation output is achieved, and stability of a power grid is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy power generation, and in particular to a coupling system for assisting in absorbing new energy and an operating method thereof. Background Art

[0002] As the proportion of renewable energy generation continues to increase, the large-scale integration of intermittent power sources such as wind and photovoltaic power poses a severe challenge to the stable operation of the power system. The high output volatility of wind and photovoltaic power generation can easily lead to grid frequency fluctuations and power imbalances, posing a challenge to the safe and stable operation of the power system. While traditional coal-fired units offer stable output, they lack flexibility, making them difficult to adapt to the demands of modern power systems.

[0003] Therefore, how to achieve dynamic balance and coordinated operation between new energy power generation units and traditional coal-fired units has become a technical problem that needs to be overcome urgently by those skilled in the art. Summary of the Invention

[0004] The purpose of the present invention is to provide a coupling system and an operating method for assisting in absorbing new energy, so as to overcome the problem in the prior art that fluctuations in the output of new energy power generation cause instability in the power grid, and traditional coal-fired units have poor flexibility and are difficult to coordinate and complement with new energy units, resulting in the power system being unable to operate efficiently and stably.

[0005] The present invention solves the above technical problems through the following technical solutions: A coupling system for assisting in absorbing new energy, including a molten salt system, a wind / solar generator set connected to the public grid, and a coal-fired generator set; The molten salt system includes a molten salt heat exchanger, a low-temperature molten salt heat storage tank, a low-temperature molten salt regulating valve, a low-temperature molten salt pump, a molten salt electric heater, a high-temperature molten salt heat storage tank, a high-temperature molten salt regulating valve and a high-temperature molten salt pump connected in sequence. The outlet of the high-temperature molten salt pump is connected to the inlet of the molten salt heat exchanger to form a first loop; The molten salt system is coupled to the coal-fired unit through a molten salt heat exchanger; a power supply device connected to the electrical input end of the molten salt electric heater is provided on the electrical output end of the wind / solar generator set.

[0006] A further improvement of the present invention is that: there are one or more wind / solar generator sets.

[0007] A further improvement of the present invention is that: the coal-fired unit includes a boiler, a steam turbine, a condenser, a condensate pump, a low-pressure heater, a deaerator, a feedwater pump and a high-pressure heater connected in sequence; the feedwater outlet of the high-pressure heater is connected to the feedwater inlet of the boiler to form a second loop; Among them, the exhaust outlet of the steam turbine is connected to the steam inlets of the low-pressure heater, high-pressure heater and deaerator respectively; the last-stage drain outlet of the high-pressure heater is connected to the drain inlet of the deaerator; the last-stage drain outlet of the low-pressure heater is connected to the drain inlet of the condenser; the feed water inlet of the molten salt heat exchanger of the coal-fired unit is connected to the feed water pump.

[0008] A further improvement of the present invention is that the coal-fired unit further comprises a steam regulating valve, and the exhaust outlet of the steam turbine is connected to the high-pressure heater via the steam regulating valve.

[0009] A further improvement of the present invention is that the coal-fired unit further includes a first feed water regulating valve, and the feed water pump is connected to the molten salt heat exchanger via the first feed water regulating valve.

[0010] A further improvement of the present invention is that the coal-fired unit further comprises a second feed water regulating valve, and the feed water pump is connected to the high-pressure heater via the second feed water regulating valve.

[0011] The present invention also provides an operating method of the coupling system for assisting in absorbing new energy based on the above-mentioned auxiliary power generation system. When the public power grid is in a low load valley or the wind / solar power generation unit has excess power generation output, the second water supply regulating valve and the steam regulating valve are increased, and the first water supply regulating valve is decreased; at the same time, the low-temperature molten salt pump and the molten salt electric heater are started, and the low-temperature molten salt in the low-temperature molten salt heat storage tank is driven by the low-temperature molten salt pump. The low-temperature molten salt enters the molten salt electric heater through the low-temperature molten salt regulating valve, and the low-temperature molten salt is converted into high-temperature molten salt, which is stored in the high-temperature molten salt heat storage tank for storing thermal energy.

[0012] A further improvement of the present invention is that when the public power grid is at a load peak or the power generation output of the wind / solar generator set is insufficient, the second water supply regulating valve and the steam regulating valve are reduced, the first water supply regulating valve is increased, the molten salt electric heater and the low-temperature molten salt pump are stopped and the high-temperature molten salt pump is started at the same time, the high-temperature molten salt pump is used to drive the high-temperature molten salt in the high-temperature molten salt heat storage tank, and the high-temperature molten salt enters the molten salt heat exchanger through the high-temperature molten salt regulating valve, so as to increase the power generation output of the coal-fired unit.

[0013] The present invention also provides an operating method of the coupling system for assisting in absorbing new energy based on the above-mentioned method. When the public power grid is in a low load valley or the wind / solar generator set has excess power generation output, a low-temperature molten salt pump is used to drive the low-temperature molten salt in the low-temperature molten salt heat storage tank, and the low-temperature molten salt is allowed to enter the molten salt electric heater through a low-temperature molten salt regulating valve, and the low-temperature molten salt is converted into high-temperature molten salt, which is then stored in the high-temperature molten salt heat storage tank for storing thermal energy.

[0014] A further improvement of the present invention is that when the public power grid is at its peak load or the power generation output of the wind / solar generator set is insufficient, a high-temperature molten salt pump is used to drive the high-temperature molten salt in the high-temperature molten salt heat storage tank, and the high-temperature molten salt is allowed to enter the molten salt heat exchanger through a high-temperature molten salt regulating valve to increase the power generation output of the coal-fired unit.

[0015] Compared with the prior art, the positive progress of the present invention is: The coupling system for assisting in absorbing new energy provided by the present invention includes a molten salt system, a wind / photovoltaic generator set connected to a public power grid, and a coal-fired unit. The molten salt system is coupled to the coal-fired unit through a molten salt heat exchanger; a power supply device connected to the electrical input end of the molten salt electric heater is provided on the electrical output end of the wind / photovoltaic generator set. By controlling the low-temperature molten salt regulating valve and the high-temperature molten salt regulating valve, the excess electric energy generated by wind and solar power generation is utilized to heat the molten salt and store the heat energy, and the heat energy is released during load peaks or when the power generation output of the wind / photovoltaic generator set is insufficient, thereby increasing the flexibility of the coal-fired unit and realizing efficient and stable operation of the power system; at the same time, with the help of the heat storage function of the molten salt system, the volatility of wind and solar power generation is alleviated, and a more stable power generation output is achieved, which is conducive to the stability of the power grid.

[0016] Furthermore, the molten salt heat exchanger serves as a coupling node between the molten salt system (first loop) and the coal-fired unit (second loop), indirectly intervening in the unit's thermal cycle through heat exchange between high-temperature molten salt and boiler feed water; the molten salt system serves as a "buffer coupling layer", converting fluctuations in renewable energy output into changes in molten salt temperature / storage, avoiding sudden changes in wind power / photovoltaic power that directly impact the power grid. When the public power grid is at its peak load or the wind / photovoltaic generator set has insufficient power generation output, the high-temperature molten salt in the high-temperature heat storage tank can continue to heat the feed water, maintain the stability of boiler input heat, reduce turbine load fluctuations, and suppress grid frequency fluctuations; the turbine extraction port is simultaneously connected to a low-pressure heater, a high-pressure heater, and a deaerator. By partially replacing the high-pressure heater with a molten salt heat exchanger, the extraction steam distribution strategy can be optimized, the complexity of multi-stage extraction steam coordinated regulation can be reduced, and the thermal balance efficiency of the power system can be improved.

[0017] Furthermore, the low-temperature molten salt regulating valve, high-temperature molten salt regulating valve, and the first and second water supply regulating valves and steam regulating valve in the water supply path of the coal-fired unit in the molten salt system form a five-valve control network to control the molten salt flow and water supply path switching. Through valve combination control, the molten salt flow and water supply distribution ratio can be accurately adjusted to achieve rapid switching of the heating path and adapt to different renewable energy output and grid load scenarios. Compared with the traditional unit relying on the single adjustment method of the turbine extraction valve, the five-valve system improves the load regulation accuracy and response speed through dynamic coupling on the fluid side (water-molten salt), meeting the modern power grid's demand for rapid peak regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0019] Figure 1 This is a schematic diagram of a coupling system for assisting in absorbing new energy according to the present invention.

[0020] Among them, 1. Boiler; 2. Steam turbine; 3. Condenser; 4. Condensate pump; 5. Low-pressure heater; 6. Deaerator; 7. Feedwater pump; 8. High-pressure heater; 9. Molten salt heat exchanger; 10. Low-temperature molten salt heat storage tank; 11. Low-temperature molten salt pump; 12. Molten salt electric heater; 13. High-temperature molten salt heat storage tank; 14. High-temperature molten salt pump; 15. Wind / solar generator set; 16. Steam regulating valve; 17. First feedwater regulating valve; 18. Second feedwater regulating valve; 19. High-temperature molten salt regulating valve; 20. Low-temperature molten salt regulating valve. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0023] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0024] Glossary: 1. The public power grid is in a low load period, which refers to the low period of the public power grid dispatch load curve, and is determined based on the real-time operation of the entire power system.

[0025] 2. Excessive power generation from wind / solar generators means that the total output of wind / solar generators exceeds the public grid's absorptive capacity, or that the voltage / frequency regulation capabilities of renewable energy grid-connected generators are insufficient, resulting in some power being restricted or abandoned. Typical scenarios include: strong winds at night but low user electricity load; or strong sunlight at noon but industrial loads not fully activated.

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, which are intended to explain the present invention rather than to limit it.

[0027] A coupling system for assisting in absorbing new energy, comprising a molten salt system, a wind / solar generator set 15 connected to a public power grid, and a coal-fired generator set; The molten salt system includes a molten salt heat exchanger 9, a low-temperature molten salt heat storage tank 10, a low-temperature molten salt regulating valve 20, a low-temperature molten salt pump 11, a molten salt electric heater 12, a high-temperature molten salt heat storage tank 13, a high-temperature molten salt regulating valve 19 and a high-temperature molten salt pump 14 connected in sequence. The outlet of the high-temperature molten salt pump 14 is connected to the inlet of the molten salt heat exchanger 9 to form a first loop; The molten salt system is coupled to the coal-fired unit through the molten salt heat exchanger 9; a power supply device connected to the power input end of the molten salt electric heater 12 is provided on the power output end of the wind / solar generator set 15.

[0028] The coupling system for assisting in absorbing new energy provided by the present invention includes a molten salt system, a wind / solar generator set 15 connected to a public power grid, and a coal-fired unit. The molten salt system is coupled to the coal-fired unit through a molten salt heat exchanger 9; a power supply device connected to the electrical input end of the molten salt electric heater 12 is provided on the electrical output end of the wind / solar generator set 15. By controlling the low-temperature molten salt regulating valve 20 and the high-temperature molten salt regulating valve 19, the excess electric energy generated by wind and solar power is used to heat the molten salt and store thermal energy, and the heat energy is released during load peaks or when the power generation output of the wind / solar generator set 15 is insufficient, thereby increasing the flexibility of the coal-fired unit and realizing efficient and stable operation of the power system; at the same time, with the help of the heat storage function of the molten salt system, the volatility of wind and solar power generation is alleviated, and a more stable power generation output is achieved, which is conducive to the stability of the power grid.

[0029] Specifically, there are one or more wind / solar generator sets 15 .

[0030] Specifically, the coal-fired unit includes a boiler 1, a steam turbine 2, a condenser 3, a condensate pump 4, a low-pressure heater 5, a deaerator 6, a feedwater pump 7, and a high-pressure heater 8 connected in sequence; the feedwater outlet of the high-pressure heater 8 is connected to the feedwater inlet of the boiler 1 to form a second loop; Among them, the exhaust outlet of the steam turbine 2 is respectively connected to the steam inlets of the low-pressure heater 5, the high-pressure heater 8 and the deaerator 6; the last-stage drain outlet of the high-pressure heater 8 is connected to the drain inlet of the deaerator 6; the last-stage drain outlet of the low-pressure heater 5 is connected to the drain inlet of the condenser 3; the feed water inlet of the molten salt heat exchanger 9 of the coal-fired unit is connected to the feed water pump 7.

[0031] The molten salt heat exchanger 9 serves as a coupling node between the molten salt system (first loop) and the coal-fired unit (second loop). It indirectly intervenes in the unit's thermal cycle by exchanging heat between high-temperature molten salt and the boiler 1 feed water. The molten salt system serves as a "buffer coupling layer", converting fluctuations in renewable energy output into changes in molten salt temperature / reserves, thereby preventing sudden changes in wind power / photovoltaic power from directly impacting the power grid. When the public power grid is at its peak load or the wind / photovoltaic generator set 15 has insufficient power generation output, the high-temperature molten salt in the high-temperature heat storage tank can continue to heat the feed water, maintain the stability of the heat input to the boiler 1, reduce load fluctuations of the steam turbine 2, and suppress grid frequency fluctuations. The steam extraction port of the steam turbine 2 is simultaneously connected to the low-pressure heater 5, the high-pressure heater 8, and the deaerator 6. By partially replacing the high-pressure heater 8 with the molten salt heat exchanger 9, the steam extraction distribution strategy can be optimized, the complexity of multi-stage steam extraction coordinated regulation can be reduced, and the thermal balance efficiency of the power system can be improved.

[0032] Specifically, the coal-fired unit further includes a steam regulating valve 16 , and the exhaust outlet of the steam turbine 2 is connected to the high-pressure heater 8 via the steam regulating valve 16 .

[0033] Specifically, the coal-fired unit further includes a first feed water regulating valve 17 , and the feed water pump 7 is connected to the molten salt heat exchanger 9 via the first feed water regulating valve 17 .

[0034] Specifically, the coal-fired unit further includes a second feed water regulating valve 18 , and the feed water pump 7 is connected to the high-pressure heater 8 via the second feed water regulating valve 18 .

[0035] In the molten salt system, the low-temperature molten salt regulating valve 20, the high-temperature molten salt regulating valve 19, the first and second water supply regulating valves 18 and the steam regulating valve 16 in the water supply path of the coal-fired unit form a five-valve control network to control the molten salt flow and the switching of the water supply path. Through the valve combination control, the molten salt flow and the water supply distribution ratio can be accurately adjusted to achieve rapid switching of the heating path to adapt to different renewable energy output and grid load scenarios; compared with the traditional unit relying on the single adjustment method of the turbine 2 extraction valve, the five-valve system improves the load regulation accuracy and response speed through dynamic coupling on the fluid side (water-molten salt), meeting the modern power grid's demand for rapid peak regulation.

[0036] Based on the same inventive concept, the present invention also provides an operating method for the coupling system based on the above-mentioned auxiliary absorption of new energy. When the public power grid is in a low load valley or the wind / solar generator set 15 has excess power generation output, the second water supply regulating valve 18 and the steam regulating valve 16 are increased, and the first water supply regulating valve 17 is decreased; at the same time, the low-temperature molten salt pump 11 and the molten salt electric heater 12 are started, and the low-temperature molten salt in the low-temperature molten salt heat storage tank 10 is driven by the low-temperature molten salt pump 11. The low-temperature molten salt enters the molten salt electric heater 12 through the low-temperature molten salt regulating valve 20, converts the low-temperature molten salt into high-temperature molten salt, and stores it in the high-temperature molten salt heat storage tank 13 for storing thermal energy.

[0037] Specifically, when the public power grid is at a load peak or the power generation output of the wind / solar generator set 15 is insufficient, the second water supply regulating valve 18 and the steam regulating valve 16 are reduced, the first water supply regulating valve 17 is increased, and the molten salt electric heater 12 and the low-temperature molten salt pump 11 are stopped and the high-temperature molten salt pump 14 is started. The high-temperature molten salt in the high-temperature molten salt heat storage tank 13 is driven by the high-temperature molten salt pump 14, and the high-temperature molten salt enters the molten salt heat exchanger through the high-temperature molten salt regulating valve 19 to increase the power generation output of the coal-fired unit.

[0038] Based on the same inventive concept, the present invention also provides an operating method for the coupled system based on the above-mentioned auxiliary absorption of new energy. When the public power grid is in a low load valley or the wind / solar generator set 15 has excess power generation output, the low-temperature molten salt in the low-temperature molten salt heat storage tank 10 is driven by a low-temperature molten salt pump 11, and the low-temperature molten salt enters the molten salt electric heater 12 through the low-temperature molten salt regulating valve 20, converts the low-temperature molten salt into high-temperature molten salt, and stores it in the high-temperature molten salt heat storage tank 13 for storing thermal energy.

[0039] Specifically, when the public power grid is at its peak load or the power generation output of the wind / solar generator set 15 is insufficient, the high-temperature molten salt pump 14 is used to drive the high-temperature molten salt in the high-temperature molten salt heat storage tank 13, and the high-temperature molten salt enters the molten salt heat exchanger through the high-temperature molten salt regulating valve 19 to increase the power generation output of the coal-fired unit.

[0040] Example 1 A coupling system for assisting in absorbing new energy, comprising a molten salt system, a wind / solar generator set 15 connected to a public power grid, and a coal-fired generator set; The molten salt system includes a molten salt heat exchanger 9, a low-temperature molten salt heat storage tank 10, a low-temperature molten salt regulating valve 20, a low-temperature molten salt pump 11, a molten salt electric heater 12, a high-temperature molten salt heat storage tank 13, a high-temperature molten salt regulating valve 19 and a high-temperature molten salt pump 14 connected in sequence. The outlet of the high-temperature molten salt pump 14 is connected to the inlet of the molten salt heat exchanger 9 to form a first loop; The molten salt system is coupled to the coal-fired unit through the molten salt heat exchanger 9; a power supply device connected to the power input end of the molten salt electric heater 12 is provided on the power output end of the wind / solar generator set 15.

[0041] When the public power grid is in a low load valley or the wind / solar power generation unit 15 has excess power generation output, the low-temperature molten salt pump 11 is used to drive the low-temperature molten salt in the low-temperature molten salt heat storage tank 10, and the low-temperature molten salt is allowed to enter the molten salt electric heater 12 through the low-temperature molten salt regulating valve 20, and the low-temperature molten salt is converted into high-temperature molten salt and stored in the high-temperature molten salt heat storage tank 13 for storing thermal energy; when the public power grid is in a peak load valley or the wind / solar power generation unit 15 has insufficient power generation output, the high-temperature molten salt pump 14 is used to drive the high-temperature molten salt in the high-temperature molten salt heat storage tank 13, and the high-temperature molten salt is allowed to enter the molten salt heat exchanger through the high-temperature molten salt regulating valve 19 for increasing the power generation output of the coal-fired unit.

[0042] "Wind / solar generator set 15" is usually used in an independent heat storage system and is not deeply coupled with the feed water heating path of the coal-fired unit. The coupling system for assisting in the absorption of new energy provided by the present invention improves the deep peak-shaving capability of the coal-fired unit by combining the wind / solar generator set 15 with the molten salt system, and promotes the efficient use of new energy. Specifically: when the public power grid is in a low load valley or the wind / solar generator set 15 has excess power generation output, the remaining power is used to drive the molten salt electric heater 12 to heat and store the low-temperature molten salt; when the public power grid is in a peak load or the wind / solar generator set 15 has insufficient power generation output, the molten salt electric heater 12 is stopped, and the heat energy is released through the molten salt heat exchanger 9 to preheat the boiler 1 feed water, thereby increasing the output power of the coal-fired unit, which not only improves the utilization efficiency of wind and solar energy, reduces coal consumption and carbon emissions, but also enhances the stability and economy of the power grid.

[0043] Example 2 See also Figure 1A coupling system for assisting in absorbing new energy, comprising a boiler 1, a steam turbine 2, a condenser 3, a condensate pump 4, a low-pressure heater 5, a deaerator 6, a feedwater pump 7, a high-pressure heater 8, a molten salt heat exchanger 9, a low-temperature molten salt heat storage tank 10, a low-temperature molten salt pump 11, a molten salt electric heater 12, a high-temperature molten salt heat storage tank 13, a high-temperature molten salt pump 14, a wind / solar generator set 15, a steam regulating valve 16, a first feedwater regulating valve 17, a second feedwater regulating valve 18, a high-temperature molten salt regulating valve 19 and a low-temperature molten salt regulating valve 20, wherein the steam outlet of the boiler 1 is connected to the steam outlet of the steam turbine 2 The steam inlet of the steam turbine 2 is connected, the exhaust port of the steam turbine 2 is connected to the condenser 3, the condensate outlet of the condenser 3 is connected to the condensate pump 4, the low-pressure heater 5, the deaerator 6, the feed water pump 7 and the high-pressure heater 8 in sequence, and the feed water outlet of the high-pressure heater 8 is connected to the feed water inlet of the boiler 1; the steam turbine 2 is provided with a plurality of steam extraction outlets, which are respectively connected to the steam inlets of the low-pressure heater 5, the high-pressure heater 8 and the deaerator 6; the last stage drain outlet of the low-pressure heater 5 is connected to the drain inlet of the condenser 3; the steam inlet of the deaerator 6 is connected to the medium-pressure The extraction outlet is connected; the final drain outlet of the high-pressure heater 8 of the high-pressure heater 8 is connected to the drain inlet of the deaerator 6; one end of the low-temperature molten salt pump 11 is connected to the low-temperature molten salt heat storage tank 10, and the other end is connected to the molten salt electric heater 12, which is used to transport the low-temperature molten salt to the molten salt electric heater 12, and the heated molten salt flows into the high-temperature molten salt heat storage tank 13; one end of the high-temperature molten salt pump 14 is connected to the high-temperature molten salt heat storage tank 13, and the other end is connected to the inlet of the molten salt side of the molten salt heat exchanger 9, and the molten salt heat exchanger 9 has a molten salt side and a water side, wherein the molten salt side inlet is connected to the high-temperature molten salt heat storage tank 13. The outlet of the molten salt pump 14 is connected, the water side inlet is connected to the water feed pump 7, and the water side outlet is connected to the water feed inlet of the boiler 1, so as to preheat the water feed of the boiler 1 and transport the high-temperature molten salt to the molten salt heat exchanger 9 to heat the water feed of the boiler 1; the power generation devices of the wind / photovoltaic generator set 15 and the coal-fired unit are connected to the public power grid through the grid-connected equipment, and the wind / photovoltaic generator set 15 and the coal-fired unit are both provided with a power supply branch connected to the electrical input end of the molten salt electric heater 12, which is used to power the molten salt electric heater 12 when the public power grid is in a low load valley or the wind / photovoltaic generator set 15 has excess power generation output.

[0044] The low-temperature molten salt pump 11 is connected to the molten salt electric heater 12 through a low-temperature molten salt regulating valve 20, and is used to control the delivery flow of the low-temperature molten salt to match the power of the molten salt electric heater 12; the feed water pump 7 is connected to the molten salt heat exchanger 9 through the first feed water regulating valve 17; the feed water pump 7 is connected to the high-pressure heater 8 through the second feed water regulating valve 18, and is used to adjust the water feed path of the boiler 1 to optimize the output of the coal-fired unit.

[0045] When the public power grid is in a low load valley or the wind / solar generator set 15 has excess power generation output, the second water supply regulating valve 18 and the steam regulating valve 16 are increased, and the first water supply regulating valve 17 is decreased; at the same time, the low-temperature molten salt pump 11 and the molten salt electric heater 12 are started, and the low-temperature molten salt in the low-temperature molten salt heat storage tank 10 is driven by the low-temperature molten salt pump 11, and the low-temperature molten salt enters the molten salt electric heater 12 through the low-temperature molten salt regulating valve 20, and the low-temperature molten salt is converted into high-temperature molten salt and stored in the high-temperature molten salt heat storage tank 13 for use. Storage of thermal energy; when the public power grid is at a peak load or the power generation output of the wind / solar generator set 15 is insufficient, the second water supply regulating valve 18 and the steam regulating valve 16 are reduced, the first water supply regulating valve 17 is increased, and at the same time, the molten salt electric heater 12 and the low-temperature molten salt pump 11 are stopped and the high-temperature molten salt pump 14 is started. The high-temperature molten salt in the high-temperature molten salt heat storage tank 13 is driven by the high-temperature molten salt pump 14, and the high-temperature molten salt enters the molten salt heat exchanger through the high-temperature molten salt regulating valve 19 to increase the power generation output of the coal-fired unit.

[0046] The coupling system for assisting in absorbing new energy provided by the present invention diverts and switches the water supply path of the boiler 1 through the first water supply regulating valve 17 and the second water supply regulating valve 18, so as to switch to the high-pressure heater 8 path or the molten salt heat exchanger 9 path under different operating conditions; the molten salt heat exchanger 9 heats the water inlet of the boiler 1 through high-temperature molten salt, forming a regulating branch in parallel with the high-pressure heater 8, thereby realizing a rapid increase in non-extraction load; it can not only realize the absorption of abandoned wind and solar power, but also release the maximum flow capacity of the unit by shutting off the steam regulating valve 16 and the extraction path when the load is increased, thereby enhancing the peak-shaving capacity of the power grid.

[0047] The coupled system establishes a dual heating path structure with a molten salt heat exchanger 9 and a high-pressure heater 8 connected in parallel. This path switching is achieved through a five-valve system (steam regulating valve 16, first feedwater regulating valve 17, second feedwater regulating valve 18, high-temperature molten salt regulating valve 19, and low-temperature molten salt regulating valve 20). This allows renewable energy to participate in load response during peak-shaving operation of the power grid while satisfying heat storage and absorption requirements, overcoming the technical limitations of traditional renewable energy integration into thermal systems, which often suffer from shallow participation and slow response. The five-valve system enables dynamic reconfiguration between the coal-fired unit's feedwater path and the renewable energy heat exchange system. The start and stop of the molten salt electric heater 12 is controlled by both changes in renewable energy output and the state of heat storage capacity. This can be achieved through the following methods: On the signal side, the heater start and stop control logic is triggered by the renewable energy output monitoring and prediction system; on the execution side, the process of converting electrical energy into thermal energy is adjusted by controlling the valves and linking the start and stop of the molten salt electric heater 12; and on the feedback mechanism, upper and lower limits are set for the molten salt storage tank temperature to achieve rapid response to heat redundancy or shortage. This strategy ensures that the system can flexibly respond to fluctuations in renewable energy while maintaining safe and stable operation of the molten salt system.

[0048] Finally, it should be noted that the embodiments listed above are merely one or more specific manifestations of the technical solution of the present invention. Their purpose is to clearly illustrate the concept, principles, and application of the present invention through specific examples, and is in no way intended to limit the scope of protection of the present invention to these specific embodiments. In fact, the true value of this invention lies in its technical ideas and innovations, not in its form of expression or implementation.

[0049] For ordinary technicians in the relevant technical field, after thoroughly reading and understanding the technical solutions of the present invention, they are fully capable of making various forms of changes, modifications or equivalent replacements to the specific implementation methods of the invention based on their own professional knowledge and skills. These changes may include but are not limited to: adjusting the value range of technical parameters, optimizing algorithm processes to improve efficiency, replacing some technical components to achieve better compatibility or reduce costs, etc. As long as these modified technical solutions still substantially maintain the technical features claimed for protection by the original invention, that is, they can still achieve the core functions and effects of the present invention, then these changes should be deemed to fall within the scope of protection of the pending claims of the present invention.

[0050] Furthermore, with the continuous advancement and development of technology, new technical means and methods continue to emerge, providing ample room for further improvement and perfection of the present invention. Therefore, the scope of protection of the present invention should also include reasonably foreseeable improvements and extensions based on existing technologies. As long as these improvements and extensions do not deviate from the basic principles and core concepts of the present invention, they should be considered equivalent to the present invention and equally protected by patent rights.

Claims

1. A coupling system for assisting in absorbing new energy, characterized in that: Including molten salt system, wind / solar generator sets (15) and coal-fired units connected to the public grid; The molten salt system comprises a molten salt heat exchanger (9), a low-temperature molten salt heat storage tank (10), a low-temperature molten salt regulating valve (20), a low-temperature molten salt pump (11), a molten salt electric heater (12), a high-temperature molten salt heat storage tank (13), a high-temperature molten salt regulating valve (19) and a high-temperature molten salt pump (14) connected in sequence, wherein the outlet of the high-temperature molten salt pump (14) is connected to the inlet of the molten salt heat exchanger (9) to form a first loop; The molten salt system is coupled to the coal-fired unit via a molten salt heat exchanger (9); a power supply device connected to the power input end of the molten salt electric heater (12) is provided on the power output end of the wind / solar power generation unit (15).

2. A coupling system for assisting in absorbing new energy according to claim 1, characterized in that: There are one or more wind / solar generator sets (15).

3. The coupling system for assisting in absorbing new energy according to claim 1, characterized in that: The coal-fired unit comprises a boiler (1), a steam turbine (2), a condenser (3), a condensate pump (4), a low-pressure heater (5), a deaerator (6), a feedwater pump (7) and a high-pressure heater (8) connected in sequence; the feedwater outlet of the high-pressure heater (8) is connected to the feedwater inlet of the boiler (1) to form a second loop; The exhaust outlet of the steam turbine (2) is connected to the steam inlets of the low-pressure heater (5), the high-pressure heater (8) and the deaerator (6), respectively; the final drain outlet of the high-pressure heater (8) is connected to the drain inlet of the deaerator (6); the final drain outlet of the low-pressure heater (5) is connected to the drain inlet of the condenser (3); and the feed water inlet of the molten salt heat exchanger (9) of the coal-fired unit is connected to the feed water pump (7).

4. A coupling system for assisting in absorbing new energy according to claim 3, characterized in that: The coal-fired unit further comprises a steam regulating valve (16), and the exhaust outlet of the steam turbine (2) is connected to the high-pressure heater (8) via the steam regulating valve (16).

5. The coupling system for assisting in absorbing new energy according to claim 4, characterized in that: The coal-fired unit further comprises a first water supply regulating valve (17), and the water supply pump (7) is connected to the molten salt heat exchanger (9) via the first water supply regulating valve (17).

6. A coupling system for assisting in absorbing new energy according to claim 5, characterized in that: The coal-fired unit further comprises a second water supply regulating valve (18), and the water supply pump (7) is connected to the high-pressure heater (8) via the second water supply regulating valve (18).

7. An operating method of the coupling system for assisting in absorbing new energy according to claim 6, characterized in that: When the public power grid is in a low load valley or the wind / solar power generation unit (15) has excess power generation output, the second water supply regulating valve (18) and the steam regulating valve (16) are increased, and the first water supply regulating valve (17) is decreased; at the same time, the low-temperature molten salt pump (11) and the molten salt electric heater (12) are started, and the low-temperature molten salt in the low-temperature molten salt heat storage tank (10) is driven by the low-temperature molten salt pump (11), and the low-temperature molten salt is allowed to enter the molten salt electric heater (12) through the low-temperature molten salt regulating valve (20), and the low-temperature molten salt is converted into high-temperature molten salt, and stored in the high-temperature molten salt heat storage tank (13) for achieving thermal energy storage.

8. The method for operating a coupling system for assisting in absorbing new energy according to claim 7, characterized in that: When the public power grid is at a peak load or the power generation output of the wind / solar power generation unit (15) is insufficient, the second water supply regulating valve (18) and the steam regulating valve (16) are reduced, the first water supply regulating valve (17) is increased, and the molten salt electric heater (12) and the low-temperature molten salt pump (11) are stopped and the high-temperature molten salt pump (14) is started. The high-temperature molten salt in the high-temperature molten salt heat storage tank (13) is driven by the high-temperature molten salt pump (14), and the high-temperature molten salt enters the molten salt heat exchanger through the high-temperature molten salt regulating valve (19), so as to increase the power generation output of the coal-fired unit.

9. An operating method of a coupling system for assisting in absorbing new energy according to any one of claims 1 to 6, characterized in that: When the public power grid is in a low load valley or the wind / solar power generation unit (15) has excess power generation output, the low-temperature molten salt in the low-temperature molten salt heat storage tank (10) is driven by the low-temperature molten salt pump (11), and the low-temperature molten salt is allowed to enter the molten salt electric heater (12) through the low-temperature molten salt regulating valve (20), and the low-temperature molten salt is converted into high-temperature molten salt, which is then stored in the high-temperature molten salt heat storage tank (13) for storing thermal energy.

10. The method for operating a coupling system for assisting in absorbing new energy according to claim 9, characterized in that: When the public power grid is at a peak load or the power generation output of the wind / solar generator set (15) is insufficient, the high-temperature molten salt in the high-temperature molten salt heat storage tank (13) is driven by the high-temperature molten salt pump (14), and the high-temperature molten salt is allowed to enter the molten salt heat exchanger through the high-temperature molten salt regulating valve (19) to increase the power generation output of the coal-fired unit.

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