Thermal power peak regulation system utilizing latent heat and working method thereof

Abstract

The invention provides a thermal power peak regulation system utilizing latent heat and a working method thereof, aims to solve the huge challenge that thermal power serves as energy supply to bear a main peak regulation power supply in a power grid system for a long time, and relates to the technical field of thermal power peak regulation. Heat energy is stored in the fused salt medium in a steam mode and an electricity mode to meet the peak regulation requirement of the thermal power generating unit, the fused salt further releases heat to return to the thermal power generating unit, and therefore the peak capacity and the operation economical efficiency of the unit are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal power peak regulation, and in particular relates to a thermal power peak regulation system utilizing latent heat and a working method thereof. Background Art

[0002] Against the backdrop of the "dual carbon" goals, a new green, low-carbon power system dominated by renewable energy is being constructed. Renewable energy has entered a new stage of large-scale, high-quality, and rapid development. The annual growth in installed capacity of renewable energy, coupled with the randomness and volatility of renewable energy, poses significant challenges to the security and stability of the power grid. To accommodate more renewable energy while ensuring the security and stability of the grid, thermal power, as the "ballast" of energy supply, will long serve as the primary peak-shaving power source in the grid system. During periods of reduced or non-existent renewable energy generation, thermal power generation must operate at full capacity to ensure a balance between the "source" and "load" sides. This places higher demands on the flexible operation of thermal power units.

[0003] Molten salt energy storage technology, as a cross-timescale energy storage technology, can be coupled with thermal power units to reduce energy losses during peak load regulation while simultaneously releasing stored energy. It is a highly promising solution for the flexibility of thermal power units. Molten salt energy storage, with its high safety, operational flexibility, high efficiency, and long lifespan, aligns well with the needs and development trends of thermal power units. To address the current challenges facing thermal power units, a latent heat-based peak load regulation system has been designed. This system uses steam (using both sensible and latent heat) and electricity to store thermal energy in a molten salt medium to meet the peak load regulation needs of the thermal power units. The molten salt then releases heat back to the thermal power units, improving their peak capacity and operational economy. Summary of the Invention

[0004] The present invention provides a thermal power peak-shaving system utilizing latent heat and its operating method, with the aim of addressing the enormous challenge faced by thermal power as the main peak-shaving power source in the power grid system for a long time as an energy supply. The system stores thermal energy in a molten salt medium through steam and electricity to meet the peak-shaving needs of the thermal power unit, further improving the release of heat from the molten salt back to the thermal power unit, thereby enhancing the peak capacity and operating economy of the unit.

[0005] The present invention adopts the following technical solutions: A thermal power peak regulation system utilizing latent heat comprises a thermal power generation system and a molten salt energy storage and heat exchange system.

[0006] Among them, the thermal power generation system includes a boiler 1, a steam turbine high-pressure cylinder 2, a steam turbine intermediate-pressure cylinder 3, a steam turbine low-pressure cylinder 4, a generator 5, a condenser 6, a first feed water pump 7, a first low-pressure heater 8, a second low-pressure heater 9, a third low-pressure heater 10, a deaerator 11, a second feed water pump 12, a first high-pressure heater 13, a second high-pressure heater 14, a third high-pressure heater 15, and a steam supply manifold 19.

[0007] Among them, the molten salt storage and heat exchange system includes a main steam-molten salt heat exchanger 16, a reheated steam-molten salt first heat exchanger 17, a reheated steam-molten salt second heat exchanger 18, a molten salt electric heater 20, a high-temperature molten salt pump group 21, a high-temperature molten salt storage tank 22, a superheater 23, an evaporator 24, a preheater 25, a low-temperature molten salt storage tank 26, a low-temperature molten salt pump group 27, a low-temperature molten salt regulating valve 29.1, a high-temperature molten salt regulating valve 29.2, a third water supply pump 30, and a regulating valve.

[0008] Preferably, the main steam of the boiler 1 is divided into two paths, the first path is connected to the high-pressure cylinder 2 of the steam turbine, and the second path is connected to the main steam-molten salt heat exchanger 16; the reheated steam of the boiler 1 is divided into three paths, the first path is connected to the intermediate-pressure cylinder 3 of the steam turbine, the second path is connected to the first reheated steam-molten salt heat exchanger 17, and the third path is connected to the second reheated steam-molten salt heat exchanger 18.

[0009] Preferably, the steam extraction port of the high-pressure cylinder 2 of the steam turbine is connected to the third high-pressure heater 15, and the exhaust steam of the high-pressure cylinder 2 of the steam turbine is respectively connected to the boiler 1 and the second high-pressure heater 14; the steam extraction port of the intermediate-pressure cylinder 3 of the steam turbine is respectively connected to the first high-pressure heater 13 and the deaerator 11, and the exhaust steam of the intermediate-pressure cylinder 3 of the steam turbine is connected to the low-pressure cylinder 4 of the steam turbine; the steam extraction port of the low-pressure cylinder 4 of the steam turbine is respectively connected to the third low-pressure heater 10, the second low-pressure heater 9, and the first low-pressure heater 8, and the exhaust steam of the low-pressure cylinder 4 of the steam turbine is connected to the condenser 6; the condensate in the condenser 6 is pressurized by the first feedwater pump 7 and then flows through the first low-pressure heater 8, the second low-pressure heater 9, the third low-pressure heater 10, the deaerator 11, and the second feed water pump 12 continue to increase the pressure and then flow through the first high-pressure heater 13, the second high-pressure heater 14, and the third high-pressure heater 15, and flow through the boiler 1 to generate steam; the third high-pressure heater 15 drains to the second high-pressure heater 14; the second high-pressure heater 14 drains to the first high-pressure heater 13; the first high-pressure heater 13 drains to the deaerator 11; the third low-pressure heater 10 drains to the second low-pressure heater 9; the second low-pressure heater 9 drains to the first low-pressure heater 8; the first low-pressure heater 8 drains to the condenser 6.

[0010] Preferably, the main steam-molten salt heat exchanger 16 is connected to the main steam of the boiler 1 and the exhaust steam of the turbine high-pressure cylinder 2 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side; the reheated steam-molten salt first heat exchanger 17 is connected to the reheated steam and the deaerator 11 of the boiler 1 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side; the reheated steam-molten salt second heat exchanger 18 is connected to the reheated steam and the steam supply manifold 19 of the boiler 1 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side. The molten salt pump group 27, the low-temperature molten salt storage tank 26, the molten salt electric heater 20, and the high-temperature molten salt storage tank 22 are connected; the molten salt electric heater 20 is connected to the generator 5, the high-temperature molten salt storage tank 22, the main steam-molten salt heat exchanger 16, the reheat steam-molten salt first heater 17, and the reheat steam-molten salt second heater 18; the high-temperature molten salt storage tank 22 is connected to the high-temperature molten salt pump group 21, the high-temperature molten salt regulating valve 29.2, the superheater 23, the evaporator 24, the preheater 25, and the low-temperature molten salt storage tank 26, and the high-temperature molten salt regulating valve 29.2 is connected to the superheater 23, the evaporator 24, and the preheater 25; the third feedwater pump 30 is connected to the superheater 23, the evaporator 24, the preheater 25, and the exhaust steam of the turbine intermediate pressure cylinder 3.

[0011] Among them, the regulating valves include a first regulating valve 28.1, a second regulating valve 28.2, a third regulating valve 28.3, a fourth regulating valve 28.4, a fifth regulating valve 28.5, a sixth regulating valve 28.6, a seventh regulating valve 28.7, and an eighth regulating valve 28.8.

[0012] A method for operating a thermal power peak-shaving system utilizing latent heat, comprising: (1) When the thermal power unit receives a deep adjustment instruction, the molten salt energy storage system is in the process of storing heat. The boiler operates at the lowest stable combustion load. The main steam generated enters the high-pressure cylinder of the steam turbine to perform work on one path, and the other path passes through the main steam-molten salt heat exchanger for heat storage, cooling and pressure reduction, and then flows into the exhaust pipe of the high-pressure cylinder of the steam turbine. After merging with the high-pressure cylinder exhaust steam, it enters the boiler for reheating; the reheated steam generated by the boiler enters the intermediate-pressure cylinder of the steam turbine to perform work on one path, and the other path is further divided into two paths through molten salt heat storage and cooling. The first path of reheated steam passes through the first reheated steam-molten salt heat exchanger and condenses into water and flows into the deaerator. Using the latent heat of the reheated steam, the second path of reheated steam passes through the second reheated steam-molten salt heat exchanger and can enter the low-pressure cylinder to continue to perform work according to the actual needs of the thermal power unit or flow into the steam supply manifold to provide steam to the outside; (2) After the low-temperature molten salt flows from the low-temperature molten salt storage tank through the low-temperature molten salt valve, it is divided into three paths and enters the main steam-molten salt heat exchanger, the reheated steam-molten salt first heat exchanger, and the reheated steam-molten salt second heat exchanger, and then flows into the molten salt electric heater. After being heated by the molten salt electric heater, the molten salt flows out into the molten salt high-temperature storage tank for storage; (3) When the molten salt energy storage system releases heat, condensate is taken from the outlet of the third low-pressure heater and pressurized by the third feed water pump before entering the preheater, evaporator, and superheater to generate steam. According to the actual needs of the thermal power unit, the condensate enters the low-pressure cylinder to continue to work or flows into the steam supply manifold to provide steam to the outside or return to the high-pressure heater system to replace the high-pressure heater extraction steam to increase the unit load; (4) The high-temperature molten salt is driven by the high-temperature molten salt pump to flow out of the high-temperature molten salt tank, and then returns to the low-temperature molten salt tank for storage after heat exchange with water or steam through the heater, evaporator, and preheater.

[0013] Preferably, the working method of the thermal power peak-shaving system using latent heat is such that the extraction amounts of main steam and reheated steam are consistent.

[0014] The present invention adopts the above technical solution and has the following beneficial effects: (1) Ensure that the extraction volume of main steam and reheat steam is consistent to avoid problems with turbine thrust. The main steam returns to the cold reheat pipe after heat exchange to avoid overheating and overspeed problems in the boiler reheater.

[0015] (2) The sensible heat and latent heat of the reheated steam are utilized at the same time, which can make greater use of the heat of the steam and improve energy utilization.

[0016] (3) According to different steam demand, the operation mode of molten salt heat release to generate steam can be flexibly adjusted to improve the overall efficiency and economy.

[0017] (4) By utilizing the extra electricity generated by the unit to heat the molten salt, the overall temperature of the molten salt can be increased, and the same volume of molten salt can store more heat.

[0018] (5) Simultaneously utilize electric heating and steam to heat molten salt, decoupling the turbine and boiler, and improving the unit's deep regulation range and new energy consumption level. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of thermal power peak regulation system using latent heat; Among them: 1- boiler, 2- turbine high-pressure cylinder, 3- turbine intermediate-pressure cylinder, 4- turbine low-pressure cylinder, 5- generator, 6- condenser, 7- first feedwater pump, 8- first low-pressure heater, 9- second low-pressure heater, 10- third low-pressure heater, 11- deaerator, 12- second feedwater pump, 13- first high-pressure heater, 14- second high-pressure heater, 15- third high-pressure heater, 16- main steam - molten salt heat exchanger, 17- reheat steam - molten salt first heat exchanger, 18- reheat steam - molten salt second heat exchanger, 19- steam supply and distribution Box, 20-molten salt electric heater, 21-high temperature molten salt pump group, 22-high temperature molten salt storage tank, 23-superheater, 24-evaporator, 25-preheater, 26-low temperature molten salt storage tank, 27-low temperature molten salt pump group, 28.1-first regulating valve, 28.2-second regulating valve, 28.3-third regulating valve, 28.4-fourth regulating valve, 28.5-fifth regulating valve, 28.6-sixth regulating valve, 28.7-seventh regulating valve, 28.8-eighth regulating valve, 29.1-low temperature molten salt regulating valve, 29.2-high temperature molten salt regulating valve, 30-third water supply pump. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0021] Example 1 A thermal power peak regulation system utilizing latent heat, the system comprising a thermal power generation system and a molten salt heat storage and exchange system; The thermal power generation system includes a boiler 1, a steam turbine high-pressure cylinder 2, a steam turbine intermediate-pressure cylinder 3, a steam turbine low-pressure cylinder 4, a generator 5, a condenser 6, a first feedwater pump 7, a first low-pressure heater 8, a second low-pressure heater 9, a third low-pressure heater 10, a deaerator 11, a second feedwater pump 12, a first high-pressure heater 13, a second high-pressure heater 14, a third high-pressure heater 15, and a steam supply header 19; The molten salt heat storage and exchange system includes a main steam-molten salt heat exchanger 16, a reheat steam-molten salt first heat exchanger 17, a reheat steam-molten salt second heat exchanger 18, a molten salt electric heater 20, a high-temperature molten salt pump group 21, a high-temperature molten salt storage tank 22, a superheater 23, an evaporator 24, a preheater 25, a low-temperature molten salt storage tank 26, a low-temperature molten salt pump group 27, a low-temperature molten salt regulating valve 29.1, a high-temperature molten salt regulating valve 29.2, a third feed water pump 30, and a regulating valve.

[0022] The main steam of boiler 1 is divided into two paths, the first path is connected to the high-pressure cylinder 2 of the steam turbine, and the second path is connected to the main steam-molten salt heat exchanger 16; the reheated steam of boiler 1 is divided into three paths, the first path is connected to the intermediate-pressure cylinder 3 of the steam turbine, the second path is connected to the first reheated steam-molten salt heat exchanger 17, and the third path is connected to the second reheated steam-molten salt heat exchanger 18. The steam extraction port of the high-pressure cylinder 2 of the steam turbine is connected to the third high-pressure heater 15, and the exhaust steam of the high-pressure cylinder 2 of the steam turbine is connected to the boiler 1 and the second high-pressure heater 14 respectively; the steam extraction port of the intermediate-pressure cylinder 3 of the steam turbine is connected to the first high-pressure heater 13 and the deaerator 11 respectively, and the exhaust steam of the intermediate-pressure cylinder 3 of the steam turbine is connected to the low-pressure cylinder 4 of the steam turbine; the steam extraction port of the low-pressure cylinder 4 of the steam turbine is connected to the third low-pressure heater 10, the second low-pressure heater 9, and the first low-pressure heater 8 respectively, and the exhaust steam of the low-pressure cylinder 4 of the steam turbine is connected to the condenser 6; the condensate in the condenser 6 is pressurized by the first feedwater pump 7 and flows through the first low-pressure heater 8, The second low-pressure heater 9, the third low-pressure heater 10, the deaerator 11, and the second feed water pump 12 continue to increase the pressure and then flow through the first high-pressure heater 13, the second high-pressure heater 14, and the third high-pressure heater 15, and flow through the boiler 1 to generate steam; the third high-pressure heater 15 drains to the second high-pressure heater 14; the second high-pressure heater 14 drains to the first high-pressure heater 13; the first high-pressure heater 13 drains to the deaerator 11; the third low-pressure heater 10 drains to the second low-pressure heater 9; the second low-pressure heater 9 drains to the first low-pressure heater 8; the first low-pressure heater 8 drains to the condenser 6. The main steam-molten salt heat exchanger 16 is connected to the main steam of the boiler 1 and the exhaust steam of the turbine high-pressure cylinder 2 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side; the reheated steam-molten salt first heat exchanger 17 is connected to the reheated steam and the deaerator 11 of the boiler 1 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side; the reheated steam-molten salt second heat exchanger 18 is connected to the reheated steam and the steam supply header 19 of the boiler 1 on the steam-water side, and is connected to the low-temperature molten salt regulating valve 29.1, the low-temperature molten salt pump group 27, the low-temperature molten salt storage tank 26, and the molten salt electric heater 20 on the molten salt side. The pump group 27, the low-temperature molten salt storage tank 26, the molten salt electric heater 20, and the high-temperature molten salt storage tank 22 are connected; the molten salt electric heater 20 is connected to the generator 5, the high-temperature molten salt storage tank 22, the main steam-molten salt heat exchanger 16, the reheat steam-molten salt first heater 17, and the reheat steam-molten salt second heater 18; the high-temperature molten salt storage tank 22 is connected to the high-temperature molten salt pump group 21, the high-temperature molten salt regulating valve 29.2, the superheater 23, the evaporator 24, the preheater 25, and the low-temperature molten salt storage tank 26, and the high-temperature molten salt regulating valve 29.2 is connected to the superheater 23, the evaporator 24, and the preheater 25; the third feedwater pump 30 is connected to the superheater 23, the evaporator 24, the preheater 25, and the exhaust steam of the turbine intermediate pressure cylinder 3.

[0023] Example 2 A method for operating a thermal power peak-shaving system utilizing latent heat, comprising: (1) When the thermal power unit receives a deep adjustment instruction, the molten salt energy storage system is in the process of storing heat. The boiler operates at the lowest stable combustion load. The main steam generated enters the high-pressure cylinder of the steam turbine to perform work on one path, and the other path passes through the main steam-molten salt heat exchanger for heat storage, cooling and pressure reduction, and then flows into the exhaust pipe of the high-pressure cylinder of the steam turbine. After merging with the high-pressure cylinder exhaust steam, it enters the boiler for reheating; the reheated steam generated by the boiler enters the intermediate-pressure cylinder of the steam turbine to perform work on one path, and the other path is further divided into two paths through molten salt heat storage and cooling. The first path of reheated steam passes through the first reheated steam-molten salt heat exchanger and condenses into water and flows into the deaerator. Using the latent heat of the reheated steam, the second path of reheated steam passes through the second reheated steam-molten salt heat exchanger and can enter the low-pressure cylinder to continue to perform work according to the actual needs of the thermal power unit or flow into the steam supply manifold to provide steam to the outside; (2) After the low-temperature molten salt flows from the low-temperature molten salt storage tank through the low-temperature molten salt valve, it is divided into three paths and enters the main steam-molten salt heat exchanger, the reheated steam-molten salt first heat exchanger, and the reheated steam-molten salt second heat exchanger, and then flows into the molten salt electric heater. After being heated by the molten salt electric heater, the molten salt flows out into the molten salt high-temperature storage tank for storage; (3) When the molten salt energy storage system releases heat, condensate is taken from the outlet of the third low-pressure heater and pressurized by the third feed water pump before entering the preheater, evaporator, and superheater to generate steam. According to the actual needs of the thermal power unit, the condensate enters the low-pressure cylinder to continue to work or flows into the steam supply manifold to provide steam to the outside or return to the high-pressure heater system to replace the high-pressure heater extraction steam to increase the unit load; (4) The high-temperature molten salt is driven by the high-temperature molten salt pump to flow out of the high-temperature molten salt tank, and then returns to the low-temperature molten salt tank for storage after heat exchange with water or steam through the heater, evaporator, and preheater.

[0024] Among them, the extraction volume of main steam and reheated steam is the same.

[0025] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A thermal power peak-shaving system utilizing latent heat, characterized by: Including thermal power generation system and molten salt energy storage and heat exchange system; The thermal power generation system comprises: a boiler (1), a steam turbine high-pressure cylinder (2), a steam turbine medium-pressure cylinder (3), a steam turbine low-pressure cylinder (4), a generator (5), a condenser (6), a first feedwater pump (7), a first low-pressure heater (8), a second low-pressure heater (9), a third low-pressure heater (10), a deaerator (11), a second feedwater pump (12), a first high-pressure heater (13), a second high-pressure heater (14), a third high-pressure heater (15), and a steam supply header (19); The molten salt energy storage and heat exchange system comprises: a main steam-molten salt heat exchanger (16), a reheat steam-molten salt first heat exchanger (17), a reheat steam-molten salt second heat exchanger (18), a molten salt electric heater (20), a high-temperature molten salt pump group (21), a high-temperature molten salt storage tank (22), a superheater (23), an evaporator (24), a preheater (25), a low-temperature molten salt storage tank (26), a low-temperature molten salt pump group (27), a low-temperature molten salt regulating valve (29.1), a high-temperature molten salt regulating valve (29.2), a third water supply pump (30), and a regulating valve.

2. The thermal power peak-shaving system utilizing latent heat according to claim 1, characterized in that: The main steam of the boiler (1) is divided into two paths, the first path is connected to the high-pressure cylinder (2) of the steam turbine, and the second path is connected to the main steam-molten salt heat exchanger (16).

3. The thermal power peak-shaving system utilizing latent heat according to claim 1, characterized in that: The reheated steam of the boiler (1) is divided into three paths, the first path is connected to the turbine intermediate pressure cylinder (3), the second path is connected to the reheated steam-molten salt first heat exchanger (17), and the third path is connected to the reheated steam-molten salt second heat exchanger (18).

4. The thermal power peak-shaving system utilizing latent heat according to claim 1, characterized in that: The steam extraction port of the high-pressure cylinder (2) of the steam turbine is connected to the third high-pressure heater (15), and the exhaust steam of the high-pressure cylinder of the steam turbine is respectively connected to the boiler (1) and the second high-pressure heater (14); the steam extraction port of the intermediate-pressure cylinder (3) of the steam turbine is respectively connected to the first high-pressure heater (13) and the deaerator (11), and the exhaust steam of the intermediate-pressure cylinder (3) of the steam turbine is connected to the low-pressure cylinder (4) of the steam turbine; the steam extraction port of the low-pressure cylinder (4) of the steam turbine is respectively connected to the third low-pressure heater (10), the second low-pressure heater (9), and the first low-pressure heater (8), and the exhaust steam of the low-pressure cylinder (4) of the steam turbine is connected to the condenser (6); the condensate in the condenser (6) is pressurized by the first feedwater pump (7) and then flows through the first low-pressure heater (8), the second low-pressure heater (9), and the first low-pressure heater (8). The water from the high-pressure heater (9), the third low-pressure heater (10), the deaerator (11), and the second feedwater pump (12) continues to increase the pressure and flows through the first high-pressure heater (13), the second high-pressure heater (14), and the third high-pressure heater (15), and flows through the boiler (1) to generate steam; the third high-pressure heater (15) drains to the second high-pressure heater (14); the second high-pressure heater (14) drains to the first high-pressure heater (13); the first high-pressure heater (13) drains to the deaerator (11); the third low-pressure heater (10) drains to the second low-pressure heater (9); the second low-pressure heater (9) drains to the first low-pressure heater (8); and the first low-pressure heater drains to the condenser (6).

5. The thermal power peak-shaving system utilizing latent heat according to claim 1, characterized in that: The main steam-molten salt heat exchanger (16) is connected to the main steam of the boiler (1) and the exhaust steam of the turbine high-pressure cylinder (2) on the steam-water side, and is connected to the low-temperature molten salt regulating valve (29.1), the low-temperature molten salt pump group (27), the low-temperature molten salt storage tank (26), and the molten salt electric heater (20) on the molten salt side; the first reheat steam-molten salt heat exchanger (17) is connected to the reheat steam and deaerator (11) of the boiler (1) on the steam-water side, and is connected to the low-temperature molten salt regulating valve (29.1), the low-temperature molten salt pump group (27), the low-temperature molten salt storage tank (26), the molten salt electric heater (20), and the high-temperature molten salt storage tank (22) on the molten salt side; the second reheat steam-molten salt heat exchanger (18) is connected to the reheat steam and the steam supply manifold (19) of the boiler (1) on the steam-water side, and is connected to the low-temperature molten salt regulating valve (29.1), the low-temperature molten salt pump group (27), the low-temperature molten salt storage tank (26), the molten salt electric heater (20), and the high-temperature molten salt storage tank (22) on the molten salt side. The pump group (27), the low-temperature molten salt storage tank (26), the molten salt electric heater (20), and the high-temperature molten salt storage tank (22) are connected; the molten salt electric heater (20) is connected to the generator (5), the high-temperature molten salt storage tank (22), the main steam-molten salt heat exchanger (16), the reheated steam-molten salt first heater (17), and the reheated steam-molten salt second heater (18); the high-temperature molten salt storage tank (22) is connected to the high-temperature molten salt pump group (21), the high-temperature molten salt regulating valve (29.2), the superheater (23), the evaporator (24), the preheater (25), and the low-temperature molten salt storage tank (26); the high-temperature molten salt regulating valve (29.2) is connected to the superheater (23), the evaporator (24), and the preheater (25); the third feedwater pump (30) is connected to the superheater (23), the evaporator (24), the preheater (25), and the exhaust steam of the turbine intermediate pressure cylinder (3).

6. The thermal power peak-shaving system utilizing latent heat according to claim 1, characterized in that: The regulating valves include a first regulating valve (28.1), a second regulating valve (28.2), a third regulating valve (28.3), a fourth regulating valve (28.4), a fifth regulating valve (28.5), a sixth regulating valve (28.6), a seventh regulating valve (28.7), and an eighth regulating valve (28.8).

7. A method for operating a thermal power peak-shaving system utilizing latent heat according to any one of claims 1 to 5, characterized in that: The working method comprises: (1) When the thermal power unit receives a deep adjustment instruction, the molten salt energy storage system is in the process of storing heat. The boiler operates at the lowest stable combustion load. The main steam generated enters the high-pressure cylinder of the steam turbine to perform work on one path, and the other path passes through the main steam-molten salt heat exchanger for heat storage, cooling and pressure reduction, and then flows into the exhaust pipe of the high-pressure cylinder of the steam turbine. After merging with the high-pressure cylinder exhaust steam, it enters the boiler for reheating; the reheated steam generated by the boiler enters the intermediate-pressure cylinder of the steam turbine to perform work on one path, and the other path is further divided into two paths through molten salt heat storage and cooling. The first path of reheated steam passes through the first reheated steam-molten salt heat exchanger and condenses into water and flows into the deaerator. Using the latent heat of the reheated steam, the second path of reheated steam passes through the second reheated steam-molten salt heat exchanger and can enter the low-pressure cylinder to continue to perform work according to the actual needs of the thermal power unit or flow into the steam supply manifold to provide steam to the outside; (2) After the low-temperature molten salt flows from the low-temperature molten salt storage tank through the low-temperature molten salt valve, it is divided into three paths and enters the main steam-molten salt heat exchanger, the reheated steam-molten salt first heat exchanger, and the reheated steam-molten salt second heat exchanger, and then flows into the molten salt electric heater. After being heated by the molten salt electric heater, the molten salt flows out into the molten salt high-temperature storage tank for storage; (3) When the molten salt energy storage system releases heat, condensate is taken from the outlet of the third low-pressure heater and pressurized by the third feed water pump before entering the preheater, evaporator, and superheater to generate steam. According to the actual needs of the thermal power unit, the condensate enters the low-pressure cylinder to continue to work or flows into the steam supply manifold to provide steam to the outside or return to the high-pressure heater system to replace the high-pressure heater extraction steam to increase the unit load; (4) The high-temperature molten salt is driven by the high-temperature molten salt pump to flow out of the high-temperature molten salt tank, and then returns to the low-temperature molten salt tank for storage after heat exchange with water or steam through the heater, evaporator, and preheater.

8. The operating method of the thermal power peak-shaving system utilizing latent heat according to claim 7, characterized in that: The extraction amounts of the main steam and the reheated steam are the same.

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