A peak-shaving and heat-storing thermal power unit and a method for operating the same

Abstract

The application discloses a kind of peak-shaving heat storage thermal power unit thermodynamic system and its operating method, belong to thermal power generation technical field;Including boiler, steam turbine high-pressure cylinder, steam turbine intermediate-pressure cylinder and steam turbine low-pressure cylinder;The first outlet of the boiler is connected steam turbine high-pressure cylinder, and the outlet of steam turbine high-pressure cylinder is connected to the second inlet of boiler;The second outlet of boiler is connected steam turbine intermediate-pressure cylinder, and the first outlet of steam turbine intermediate-pressure cylinder is sequentially connected with heat storage unit and feedwater heater, and feedwater heater is connected to the first inlet of boiler;The second outlet of steam turbine intermediate-pressure cylinder is sequentially connected steam turbine low-pressure cylinder, condenser and condensate pump;The outlet of the condensate pump is divided into two ways, one is sequentially connected condensate heater and deaerator, and the deaerator is connected to feedwater heater;The other way of condensate pump outlet is connected to heat storage unit. Heat storage technology and thermal power unit thermodynamic system are efficiently combined.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of thermal power generation, and relates to a peak regulation and heat storage thermal power unit thermal system and a running method thereof. BACKGROUND

[0002] Under the background of energy structure transformation and upgrading, the proportion of new energy power generation is increasing year by year, especially the rapid development of clean energy such as wind power and photovoltaic power. However, new energy power generation has intermittency and instability, and its output is greatly affected by weather and other natural factors, which puts higher requirements on the peak regulation capacity of the power grid. As the main body of traditional power supply, thermal power units not only need to continue to bear the basic power supply task in the process of energy structure transformation, but also need to supplement power in time when new energy output is insufficient, and reduce output when new energy output is at peak, so as to make room for new energy power supply.

[0003] With the rapid development of new energy power generation, the demand for power grid peak regulation is increasing. Especially during the period of large wind power and photovoltaic power generation, the power grid needs to quickly adjust the load to balance the fluctuation of new energy power generation. However, the traditional peak regulation method of reducing the load of conventional power plants cannot meet the increasing demand for wind power. Therefore, more ideas for wind power accommodation need to be sought to improve the peak regulation capacity of the power grid.

[0004] In order to meet the development needs of new energy power generation, thermal power units need to carry out deep peak regulation technology research. Deep peak regulation technology refers to the technology that thermal power units can safely and stably operate at low load. Through deep peak regulation, thermal power units can reduce output when new energy output is at peak, making room for new energy power supply; at the same time, they can supplement power in time when new energy output is insufficient, ensuring the safe and stable operation of the power grid. However, thermal power units will face a series of technical challenges during deep peak regulation, such as boiler combustion stability, turbine operation efficiency, and normal operation of environmental protection system.

[0005] In order to solve the problems faced by thermal power units during deep peak regulation and improve the peak regulation capacity of the power grid, heat storage peak regulation technology is introduced. Heat storage peak regulation technology uses heat storage devices to convert electrical energy into thermal energy and store it during the low valley period of the power grid, and releases the stored thermal energy to meet the peak regulation demand of the power grid during the peak period of the power grid. However, the existing technology cannot efficiently combine heat storage technology with the thermal system of thermal power units, resulting in serious waste of thermal energy and safety hazards. SUMMARY

[0006] The purpose of the present application is to provide a peak regulation and heat storage thermal power unit thermal system and a running method thereof, to solve the technical problems in the prior art that heat storage technology cannot be efficiently combined with the thermal system of thermal power units, resulting in serious waste of thermal energy and safety hazards.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] In a first aspect, the present invention provides a peak-shaving thermal storage power unit thermal system, comprising a boiler, a high-pressure cylinder of a steam turbine, an intermediate-pressure cylinder of a steam turbine, and a low-pressure cylinder of a steam turbine; the first outlet of the boiler is connected to the high-pressure cylinder of the steam turbine, and the outlet of the high-pressure cylinder of the steam turbine is connected to the second inlet of the boiler; the second outlet of the boiler is connected to the intermediate-pressure cylinder of the steam turbine, and the first outlet of the intermediate-pressure cylinder of the steam turbine is sequentially connected to a thermal storage unit and a feedwater heater, the feedwater heater being connected to the first inlet of the boiler; the second outlet of the intermediate-pressure cylinder of the steam turbine is sequentially connected to the low-pressure cylinder of the steam turbine, a condenser, and a condensate pump; the outlet of the condensate pump is divided into two paths, one path being sequentially connected to a condensate heater and a deaerator, the deaerator being connected to the feedwater heater; the other path of the condensate pump outlet is connected to the thermal storage unit.

[0009] Furthermore, the heat storage unit includes a hot water storage tank, a heat exchanger, and a heat storage deoxygenated water tank; the heat storage deoxygenated water tank is filled with water, and the first outlet of the intermediate pressure cylinder of the steam turbine is connected to the water in the heat storage deoxygenated water tank through a pipeline; the bottom of the heat storage deoxygenated water tank has an outlet and an inlet, the inlet is connected to the condensate pump through a pipeline, and the outlet is connected to the feedwater heater through a pipeline; a heat exchanger and a hot water storage tank are also connected in sequence on one side of the heat storage deoxygenated water tank, and the hot water storage tank can store the excess heat energy in the heat storage deoxygenated water tank.

[0010] Furthermore, an immersion jet nozzle device is installed at the outlet of the pipeline connecting the first outlet of the intermediate pressure cylinder of the steam turbine to the heat storage deaerator.

[0011] Furthermore, a second water pump is installed on the pipeline between the bottom outlet of the thermal deoxygenation tank and the water heater.

[0012] Furthermore, the heat exchanger is a plate heat exchanger.

[0013] Furthermore, a first feedwater pump is installed on the connecting pipe between the deaerator and the feedwater heater.

[0014] Furthermore, several condensate heaters are provided, connected in series, for heating the condensate in stages.

[0015] Furthermore, several water heaters are provided, connected in series, for heating the water supply in stages.

[0016] Secondly, the present invention provides an operation method for the above-mentioned peak-shaving and thermal storage thermal power unit thermal system, comprising the following steps:

[0017] When there is no peak-shaving demand, the thermal power unit operates at 60% to 70% load. The steam generated by the boiler passes through the high-pressure cylinder, intermediate-pressure cylinder, and low-pressure cylinder of the turbine in sequence. The exhaust steam from the low-pressure cylinder enters the condenser, where it condenses into water. The water then passes through the condensate pump, condensate heater, deaerator, and feedwater heater in sequence before finally returning to the boiler.

[0018] When thermal power units are operating at peak load, they generate electricity at a load of less than 60% and store excess heat energy through thermal storage units.

[0019] When the thermal power unit is operating at its peak load, it generates electricity at a rate of over 70%. The steam generated by the boiler passes sequentially through the high-pressure cylinder, intermediate-pressure cylinder, and low-pressure cylinder of the turbine, the condenser, the condensate pump, the condensate heater, the deaerator, and the feedwater heater before finally returning to the boiler. External heat demand is met by the heat stored in the thermal storage unit.

[0020] Furthermore, during peak-shaving operation of the thermal power unit, when it is generating electricity at a load below 60%, the step of storing surplus thermal energy through a thermal storage unit specifically includes:

[0021] When the peak-shaving demand of the thermal power unit is large, it is in the state of generating electricity at a load below 40%. The steam generated by the boiler enters the high-pressure cylinder and intermediate-pressure cylinder of the steam turbine. All the exhaust steam from the intermediate-pressure cylinder of the steam turbine is discharged into the thermal storage deaerator water tank. The water level in the thermal storage deaerator water tank is kept stable, and the flow rate at the inlet of the thermal storage deaerator water tank and the outlet of the second feed water pump are balanced.

[0022] When the peak demand of the thermal power unit is relatively small, it operates at 40% to 60% load. The steam generated by the boiler enters the high-pressure cylinder and intermediate-pressure cylinder of the turbine. A portion of the exhaust steam from the intermediate-pressure cylinder is sent to the heat storage deaerator tank to store heat. The other portion of the exhaust steam from the intermediate-pressure cylinder passes through the low-pressure cylinder, condenser, and condensate pump in sequence. The condensate is divided into two paths by the condensate pump. One path passes through the condensate pump, condensate heater, deaerator, first feedwater pump, and water heater in sequence. The other path passes through the condensate pump, second feedwater pump, and water heater in sequence. Both paths eventually return to the boiler.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention discloses a peak-shaving thermal storage thermal power unit thermal system and its operation method. It introduces the majority of the exhaust steam from the intermediate-pressure cylinder of existing thermal power generation systems (leaving only the minimum flow required by the low-pressure cylinder) into the thermal storage deaerator tank (essentially achieving low-pressure cylinder cut-off), increasing the unit's peak-shaving depth when needed. This significantly reduces the cold source loss of existing thermal power generation systems, namely the latent heat of the condenser exhaust steam, transferring this heat to the thermal storage unit for storage and external heating when needed, converting cold source loss into heating revenue. When the turbine generator unit needs to reduce load for peak shaving, this invention reduces the unit's power generation by decreasing the steam intake of the turbine's low-pressure cylinder without changing the original boiler operating load, thereby reducing the amount of electricity fed into the grid. Simultaneously, it reduces the cold source loss of the condenser, storing this heat. This breaks through the limitation of existing northern thermal power units only being able to operate with zero output from the low-pressure cylinder during the heating season, enabling deep peak shaving throughout the year. It has good operational flexibility and peak-shaving effect, making it very suitable for the current electricity spot market rules.

[0025] Furthermore, this invention uses a heat exchanger to separate the circulation of the hot water storage tank and the thermal deaeration tank, which can maintain the water quality of the generator set's thermal system without being affected by external heat exchange media. The hot water storage tank in this invention enables cross-seasonal heat storage, storing the heat from the summer unit for winter heating, and also allowing for heating to be provided as needed. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a peak-shaving thermal storage thermal power unit thermal system according to the present invention.

[0028] Wherein: 1-boiler; 2-high-pressure cylinder of steam turbine; 3-intermediate-pressure cylinder of steam turbine; 4-low-pressure cylinder of steam turbine; 5-feed water heater; 6-first feed water pump; 7-deaerator; 8-condensate heater; 9-condenser; 10-hot water storage tank; 11-heat exchanger; 12-immersion jet nozzle device; 13-heat storage deaerator tank; 14-condensate pump; 15-second feed water pump. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0032] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0033] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0034] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0035] The present invention will now be described in further detail with reference to the accompanying drawings:

[0036] SeeFigure 1 This invention addresses the challenges faced by thermal power plants in peak shaving and frequency regulation, flexible operation, and supporting regulatory functions within new power systems. It proposes a peak-shaving, thermal storage thermal power unit thermal system, comprising a boiler 1, a high-pressure turbine cylinder 2, a medium-pressure turbine cylinder 3, and a low-pressure turbine cylinder 4. The first outlet of the boiler 1 is connected to the high-pressure turbine cylinder 2, and the outlet of the high-pressure turbine cylinder 2 is connected to the second inlet of the boiler 1. The second outlet of the boiler 1 is connected to the medium-pressure turbine cylinder 3. The first outlet of the medium-pressure turbine cylinder 3 is sequentially connected to a thermal storage unit and a feedwater heater 5, which is connected to the first inlet of the boiler 1. The second outlet of the medium-pressure turbine cylinder 3 is sequentially connected to the low-pressure turbine cylinder 4, a condenser 9, and a condensate pump 14. The outlet of the condensate pump 14 is divided into two paths: one path is sequentially connected to a condensate heater 8 and a deaerator 7, with the deaerator 7 connected to the feedwater heater 5; the other path of the condensate pump 14 outlet is connected to the thermal storage unit.

[0037] In this embodiment, the main steam from boiler 1 enters the high-pressure cylinder 2 of the turbine to perform work; the exhaust steam from the high-pressure cylinder 2 returns to boiler 1 for reheating and then enters the intermediate-pressure cylinder 3 of the turbine to perform work; the exhaust steam from the intermediate-pressure cylinder 3 is divided into two paths: one path enters the low-pressure cylinder 4 of the turbine to perform work, and the other path enters the heat storage unit; the exhaust steam from the low-pressure cylinder 4 enters the condenser 9 and is condensed into condensate. The condensate can either return to the boiler via the condensate pump 14, condensate heater 8, deaerator 7, first feedwater pump 6, and feedwater heater 5 in sequence; or it can return to the boiler via the condensate pump 14, heat storage unit, and feedwater heater 5 in sequence.

[0038] This embodiment of the system configures new thermal and heat storage equipment around the original thermal power unit's thermal system and connects it with the original thermal system to form a thermal power unit thermal system that can achieve peak shaving and heat storage. When the unit needs to reduce load for peak shaving, the thermal power unit reduces the amount of electricity fed into the grid by increasing the steam extraction of the original turbine intermediate-pressure cylinder 3 without changing the original boiler operating load. At the same time, since the steam intake of the turbine low-pressure cylinder 4 is reduced, the cold source loss is greatly reduced. This system stores the heat from the reduced cold source loss in the heat storage unit and supplies heat to the outside when needed. In this way, the unit can achieve zero output of the low-pressure cylinder throughout the year, increasing the unit's peak shaving depth and operational flexibility.

[0039] The advantage of doing this is that it makes the load changes of thermal power units unaffected by the minimum stable combustion load of the power plant boiler, increases the peak shaving depth of thermal power units, ensures the stable and safe operation of the boiler and turbine of the unit, and increases the service life of the boiler and turbine.

[0040] In one feasible embodiment of the present invention, the heat storage unit includes a hot water storage tank 10, a heat exchanger 11, and a heat storage deoxygenated water tank 13; the heat storage deoxygenated water tank 13 is filled with water, and the first outlet of the intermediate pressure cylinder 3 of the steam turbine is connected to the water in the heat storage deoxygenated water tank 13 through a pipeline; the bottom of the heat storage deoxygenated water tank 13 has an outlet and an inlet, the inlet is connected to the condensate pump 14 through a pipeline, and the outlet is connected to the feedwater heater 5 through a pipeline; the heat exchanger 11 and the hot water storage tank 10 are also connected in sequence on one side of the heat storage deoxygenated water tank 13, and the hot water storage tank 10 can store the excess heat energy in the heat storage deoxygenated water tank 13.

[0041] In this embodiment, the water level in the heat storage deoxygenation water tank 13 remains constant. The heat source for heating the water inside is the phase change heat transfer between the exhaust steam from the medium-pressure cylinder and the water in the tank via the submerged jet device 12. The water temperature in the tank is distributed in layers, with higher temperatures at the top and lower temperatures at the bottom. The water temperature at the bottom of the tank matches the inlet temperature of the feedwater heater 5. Because the water temperature at the top of the tank is higher, the water circulates internally within the water pipes. Figure 1 The water flows counterclockwise into heat exchanger 11 to release excess heat. The heat storage and deoxygenation water tank 13 has two functions: first, to thermally deoxygenate the water in the tank; and second, to achieve a certain degree of heat storage. The water temperature distribution in the hot water storage tank 10 is also higher at the top and lower at the bottom, with water circulating within the tank according to... Figure 1 The direction is counterclockwise into the heat exchanger 11; the hot water storage tank 10 is a large container of water, and through seepage prevention, heat preservation and reasonable water distribution, it can achieve cross-seasonal heat storage function.

[0042] In one feasible embodiment of the present invention, a second feedwater pump 15 is installed on the pipeline between the bottom outlet of the thermal storage deaerator 13 and the feedwater heater 5. A first feedwater pump 6 is installed on the connecting pipeline between the deaerator 7 and the feedwater heater 5. The heat exchanger 11 is preferably, but is not limited to, a plate heat exchanger.

[0043] In one feasible embodiment of the present invention, several condensate heaters 8 are provided, preferably four, connected in series, for staged heating of the condensate; the heat source is low-pressure cylinder extraction steam (not shown in the figure), and the condensate temperature increases stage by stage from the condensate pump 14 to the deaerator 7. Several feedwater heaters 5 are provided, preferably three, connected in series, for staged heating of the feedwater; the heat source is high- and medium-pressure cylinder extraction steam (not shown in the figure), and the feedwater temperature increases stage by stage from the deaerator 7 to the boiler 1.

[0044] This invention discloses an operation method for the thermal system of the above-mentioned peak-shaving and thermal storage thermal power unit, comprising the following steps:

[0045] 1. The thermal power unit is operating normally.

[0046] When there is no peak-shaving demand, the thermal power unit operates at high load. The steam generated by boiler 1 passes sequentially through the high-pressure cylinder 2, intermediate-pressure cylinder 3, and low-pressure cylinder 4 of the turbine. The exhaust steam from the low-pressure cylinder 4 enters the condenser 9, where it condenses into water. The water then passes sequentially through the condensate pump 14, condensate heater 8, deaerator 7, and feedwater heater 5, finally returning to boiler 1. The working fluid circulates in the following order: (boiler 1 - high-pressure cylinder 2 - intermediate-pressure cylinder 3 - low-pressure cylinder 4 - condenser 9 - condensate pump 14 - condensate heater 8 - deaerator 7 - first feedwater pump 6 - feedwater heater 5 - boiler 1). The above-mentioned unit operates at approximately 60%-70% or higher of its power generation load.

[0047] 2. Peak-shaving operation of thermal power units.

[0048] When generating electricity at a load below 60%, excess heat energy is stored through a thermal storage unit.

[0049] 3. Thermal power units are operating at peak capacity.

[0050] The steam generated by boiler 1 passes sequentially through the high-pressure cylinder 2, intermediate-pressure cylinder 3, and low-pressure cylinder 4 of the turbine, condenser 9, condensate pump 14, condensate heater 8, deaerator 7, and feedwater heater 5, finally returning to boiler 1. External heat demand is met by heat stored in the thermal storage unit, reducing the amount of steam extracted from the unit and achieving increased grid-connected power generation and peak load. The above-mentioned unit operates at approximately 70% or higher of its power generation load.

[0051] In one feasible embodiment of the present invention, the step of peak-shaving operation of the thermal power unit specifically includes:

[0052] When the peak-shaving demand of the thermal power unit is large, it operates at a load below 40%. The steam generated by boiler 1 enters the high-pressure cylinder 2 and the intermediate-pressure cylinder 3 of the turbine. All the exhaust steam from the intermediate-pressure cylinder 3 is discharged into the thermal storage deaerator tank 13 (only the minimum flow rate of the low-pressure cylinder 4 is retained), achieving zero output from the low-pressure cylinder. The water level in the thermal storage deaerator tank 13 is kept stable, and the flow rates at the inlet of the thermal storage deaerator tank 13 and the outlet of the second feedwater pump 15 are balanced. Due to the reduction of cold source losses, if all the heat in the thermal storage deaerator tank 13 were returned to the unit's thermal system, it would disrupt the original thermal system balance. Therefore, heat exchanger 11 is used to send the excess heat to the hot water storage tank for storage. The working fluid circulates in the following order: (boiler 1 - high-pressure cylinder 2 - intermediate-pressure cylinder 3 - submerged jet nozzle device 12 - thermal storage deaerator tank 13 - second feedwater pump 15 - feedwater heater 5 - boiler 1).

[0053] When the peak demand of the thermal power unit is relatively small, it operates at 40% to 60% load. The steam generated by boiler 1 enters the high-pressure cylinder 2 and the intermediate-pressure cylinder 3 of the turbine. A portion of the exhaust steam from the intermediate-pressure cylinder 3 is fed into the heat storage deaerator tank 13 to store heat. The other portion of the exhaust steam from the intermediate-pressure cylinder 3 passes through the low-pressure cylinder 4, condenser 9, and condensate pump 14 in sequence. The condensate is divided into two paths by condensate pump 14. One path passes through condensate pump 14, condensate heater 8, deaerator 7, first feedwater pump 6, and water heater 5 in sequence. The other path passes through condensate pump 14, second feedwater pump 15, and water heater 5 in sequence. Both paths eventually return to boiler 1.

[0054] The working process / working principle of this invention is as follows:

[0055] When a steam turbine generator unit needs to reduce load for peak shaving, the unit's power generation is reduced by decreasing the steam intake of the turbine's low-pressure cylinder 4 without changing the original boiler operating load, thereby reducing the amount of electricity fed into the grid. Simultaneously, the cold source loss of the condenser 9 is reduced, and this heat is stored in the hot water storage tank 10. Because of the hot water storage tank 10, this system overcomes the limitation of existing northern thermal power units only being able to operate with zero output from the low-pressure cylinder during the heating season, enabling deep peak shaving throughout the year. It has good operational flexibility and peak shaving effect, making it very suitable for the existing electricity spot market rules.

[0056] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A peak-shaving thermal storage thermal power unit thermal power system, characterized in that, The system includes a boiler (1), a high-pressure cylinder (2) of a steam turbine, an intermediate-pressure cylinder (3) of a steam turbine, and a low-pressure cylinder (4) of a steam turbine. The first outlet of the boiler (1) is connected to the high-pressure cylinder (2) of the steam turbine, and the outlet of the high-pressure cylinder (2) of the steam turbine is connected to the second inlet of the boiler (1). The second outlet of the boiler (1) is connected to the intermediate-pressure cylinder (3) of the steam turbine. The exhaust of the intermediate-pressure cylinder (3) of the steam turbine is divided into two paths, one of which enters the low-pressure cylinder (4) of the steam turbine to do work, and the other of which enters the heat storage unit. The first outlet of the intermediate-pressure cylinder (3) of the steam turbine is connected in sequence to the heat storage unit and the feedwater heater (5), and the feedwater heater (5) is connected to the first inlet of the boiler (1). The second outlet of the intermediate-pressure cylinder (3) of the steam turbine is connected in sequence to the low-pressure cylinder (4) of the steam turbine, the condenser (9), and the condensate pump (14). The outlet of the condensate pump (14) is divided into two paths, one of which is connected in sequence to the... A condensate heater (8) and a deaerator (7) are provided, the deaerator (7) being connected to the feedwater heater (5); another path of the outlet of the condensate pump (14) is connected to the heat storage unit; the heat storage unit includes a hot water storage tank (10), a heat exchanger (11), and a heat storage deaerator tank (13); the heat storage deaerator tank (13) is filled with water, and the first outlet of the intermediate pressure cylinder (3) of the steam turbine is connected to the water in the heat storage deaerator tank (13) through a pipe; the bottom of the heat storage deaerator tank (13) has an outlet and an inlet, the inlet being connected to the condensate pump (14) through a pipe, and the outlet being connected to the feedwater heater (5) through a pipe; a heat exchanger (11) and a hot water storage tank (10) are also connected in sequence on one side of the heat storage deaerator tank (13), the hot water storage tank (10) being able to store the excess heat energy in the heat storage deaerator tank (13).

2. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, An immersion jet nozzle device (12) is installed at the outlet of the pipeline connecting the first outlet of the intermediate pressure cylinder (3) of the steam turbine to the heat storage deaerator (13).

3. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, A second water pump (15) is installed on the pipeline between the bottom outlet of the thermal deoxygenation tank (13) and the water heater (5).

4. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, The heat exchanger (11) is a plate heat exchanger.

5. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, A first water pump (6) is installed on the connecting pipe between the deaerator (7) and the water heater (5).

6. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, The condensate heater (8) is provided in several units, connected in series, for heating the condensate step by step.

7. The peak-shaving thermal storage thermal power unit thermal system according to claim 1, characterized in that, The water heater (5) is provided in several units, connected in series, for heating the water supply in stages.

8. A method for operating the thermal system of a peak-shaving thermal storage power unit as described in any one of claims 1 to 7, characterized in that, Includes the following steps: When there is no peak demand, the thermal power unit is in a 60%~70% load power generation state. The steam generated by the boiler (1) passes through the high pressure cylinder (2), the intermediate pressure cylinder (3) and the low pressure cylinder (4) of the turbine in sequence. The exhaust steam of the low pressure cylinder (4) enters the condenser (9) and condenses into water in the condenser (9). Then the water passes through the condensate pump (14), the condensate heater (8), the deaerator (7) and the feedwater heater (5) in sequence, and finally returns to the boiler (1). When thermal power units are operating at peak load, they generate electricity at a load of less than 60% and store excess thermal energy through thermal storage units. When the thermal power unit is in peak operation, it is generating electricity at a load of over 70%. The steam generated by the boiler (1) passes through the high-pressure cylinder (2), the intermediate-pressure cylinder (3), and the low-pressure cylinder (4) of the turbine, the condenser (9), the condensate pump (14), the condensate heater (8), the deaerator (7), and the feedwater heater (5) in sequence, and finally returns to the boiler (1). The external heat demand is supplied by the heat stored in the heat storage unit.

9. The operation method of a peak-shaving thermal storage thermal power unit thermal system according to claim 8, characterized in that, When the thermal power unit operates at peak load and is generating electricity at a load below 60%, the steps for storing surplus thermal energy through a thermal storage unit specifically include: When the peak demand of the thermal power unit is large, it is in the state of generating electricity at a load of less than 40%. The steam generated by the boiler (1) enters the high pressure cylinder (2) and the intermediate pressure cylinder (3) of the turbine. All the exhaust steam from the intermediate pressure cylinder (3) of the turbine is discharged into the heat storage deaerator water tank (13). The water level in the heat storage deaerator water tank (13) is kept stable, and the flow rate at the inlet of the heat storage deaerator water tank (13) and the outlet of the second feed water pump (15) are balanced. When the peak demand of the thermal power unit is small, it is in the state of generating electricity at 40%~60% load. The steam generated by the boiler (1) enters the high pressure cylinder (2) and the intermediate pressure cylinder (3) of the turbine. Part of the exhaust steam from the intermediate pressure cylinder (3) of the turbine is sent to the heat storage deaerator tank (13) to store the heat. The other part of the exhaust steam from the intermediate pressure cylinder (3) of the turbine passes through the low pressure cylinder (4), the condenser (9) and the condensate pump (14) in sequence. The condensate is divided into two paths by the condensate pump (14). One path passes through the condensate pump (14), the condensate heater (8), the deaerator (7), the first feedwater pump (6) and the feedwater heater (5) in sequence. The other path passes through the condensate pump (14), the heat storage unit, the second feedwater pump (15) and the feedwater heater (5) in sequence. The two paths eventually return to the boiler (1).

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