Thermal power generating unit combined heat and power generation system and method based on energy storage

Abstract

The invention particularly relates to a thermal power generating unit combined heat and power generation system and method based on energy storage. The system comprises a back extraction type thermal power generation module, a high-temperature heat storage module and a compressed air energy storage power generation module. The back extraction type thermal power generation module comprises a steam boiler; the high-temperature heat storage module comprises a high-temperature heat storage heat exchanger, an air heater and a heating medium water vapor generator; the compressed air energy storage power generation module comprises an air cooler and an air expansion machine; the back extraction type thermal power generation module heats the high-temperature heat storage module through the high-temperature heat storage heat exchanger. The high-temperature heat storage module is used for heating inlet air of an air expansion machine in the compressed air energy storage power generation module through an air heater; the compressed air energy storage power generation module provides steam boiler water preheating for the back extraction type thermal power generation module through an air cooler. The flexibility of the back-drawn thermal power generation module can be improved, stable heat supply is guaranteed, and meanwhile deep peak regulation or peak thermoelectric supply is achieved through energy storage.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic recycling, and in particular relates to a thermal power cogeneration system and method based on energy storage. Background Art

[0002] Thermal power generation is the main basic load power source of my country's power system. As the peak-to-valley load difference of the power grid widens, the demand for thermal power generating units to participate in deep peak regulation is increasing. At the same time, driven by the strategy of accelerating the construction of a new power system in my country, the proportion of wind and solar power sources in the power system is also increasing. Since the output of wind and solar power has the characteristics of short-term grid-connected peak, it further increases the pressure of deep peak regulation of traditional thermal power generation.

[0003] Therefore, there is an urgent need for a thermal power unit cogeneration system and method based on energy storage, which can improve the unit's deep peak-shaving capability and peak power generation capacity, and respond to the peak-shaving and peak-power requirements of the power grid. Summary of the Invention

[0004] The purpose of the present invention is to provide a thermal power cogeneration system and method based on energy storage for thermal power generation units. By configuring a high-temperature heat storage module, thermal and electrical decoupling of the thermal power generation unit is achieved, while at the same time, the deep peak-shaving capability of the unit is enhanced. The compressed air energy storage power generation module is used to absorb valley electricity from the power grid or directly consume the output power of the thermal power generation unit, thereby further improving the overall deep peak-shaving capability of the system. By synchronously generating electricity through the back-drawn thermal power generation module and the compressed air energy storage power generation module, the overall peak power generation capacity of the system can be improved.

[0005] In order to solve the above technical problems, the present invention provides a thermal power cogeneration system and method based on energy storage, comprising:

[0006] A back-drawn thermal power generation module, a high-temperature heat storage module and a compressed air energy storage power generation module; the back-drawn thermal power generation module includes a steam boiler; the high-temperature heat storage module includes: a high-temperature heat storage heat exchanger, an air heater, and a heat medium water vapor generator; the compressed air energy storage power generation module includes: an air cooler and an air expander; the back-drawn thermal power generation module heats the high-temperature heat storage module through the high-temperature heat storage heat exchanger; the high-temperature heat storage module heats the air expander intake in the compressed air energy storage power generation module through the air heater; the compressed air energy storage power generation module provides steam boiler water preheating for the back-drawn thermal power generation module through the air cooler; the back-drawn thermal power generation module operates independently in a cycle to form mode one; the back-drawn thermal power generation module and the high-temperature heat storage module and / or the compressed air energy storage power generation module operate jointly to form mode two; the back-drawn thermal power generation module, the high-temperature heat storage module and the compressed air energy storage power generation module operate jointly to form mode three.

[0007] Furthermore, the back-drawn thermal power generation module also includes: a back-drawn steam turbine; the back-drawn steam turbine includes: a high-pressure cylinder and a low-pressure cylinder; the first outlet of the steam boiler is connected to the inlet of the high-pressure cylinder; the second outlet of the steam boiler is connected to the high-temperature side inlet of the high-temperature heat storage heat exchanger; the high-temperature side outlet of the high-temperature heat storage heat exchanger is connected to the external high-temperature steam load; the high-pressure cylinder is connected to the external high-temperature steam load through the high-temperature steam extraction port; the exhaust port of the low-pressure cylinder is connected to the external medium-temperature steam load; the return steam of the low-pressure cylinder is absorbed by a heating heat exchanger and cooled down and then flows back to the steam boiler; the low-temperature side of the heating heat exchanger is connected to the external low-temperature heating load.

[0008] Furthermore, the high-temperature heat storage module also includes: a first high-temperature heat accumulator, a first high-temperature circulation pump, a second high-temperature heat accumulator, and a second high-temperature circulation pump; the high-temperature heat storage heat exchanger, the first high-temperature heat accumulator, the first high-temperature circulation pump, the air heater, the heat medium water vapor generator, the second high-temperature heat accumulator, and the second high-temperature circulation pump are arranged in a cycle in sequence.

[0009] Furthermore, the compressed air energy storage power generation module also includes: an air compressor and an air storage reservoir; the air compressor, air cooler, air storage reservoir, air heater, and air expander are arranged in series in sequence.

[0010] Furthermore, the energy storage-based thermal power unit cogeneration system also includes: a medium-temperature heat accumulator; the inlet of the medium-temperature heat accumulator is connected to the low-temperature side outlet of the air cooler; the first outlet of the medium-temperature heat accumulator is connected to the low-temperature side inlet of the heat medium water vapor generator through a first medium-temperature circulation pump; the low-temperature side outlet of the heat medium water vapor generator is connected to an external medium-temperature steam load; the second outlet of the medium-temperature heat accumulator is connected to the inlet of the steam boiler through a second medium-temperature circulation pump; and the third outlet of the medium-temperature heat accumulator is connected to an external low-temperature heating load.

[0011] In another aspect, the present invention further provides a method for operating a thermal power cogeneration system based on energy storage, comprising:

[0012] In mode 1, the steam boiler supplies high-temperature steam to the high-pressure cylinder by heating external make-up water and exhaust steam from the low-pressure cylinder to drive the back-type steam turbine and its associated generator; the high-pressure cylinder supplies steam to the external high-temperature steam load through the high-temperature steam extraction port; the exhaust port of the low-pressure cylinder supplies steam to the external medium-temperature steam load.

[0013] Furthermore, in mode 2, part of the high-temperature exhaust steam of the steam boiler enters the high-temperature side of the high-temperature heat storage heat exchanger to heat the high-temperature heat storage medium of the second high-temperature heat accumulator. The high-temperature heat storage medium absorbs heat and is heated up and then stored in the first high-temperature heat accumulator; the high-temperature steam after the high-temperature heat storage heat exchanger releases heat and cools down is supplied to the external high-temperature steam load through the high-temperature side outlet, and the remaining high-temperature steam returns to the steam boiler through the heating heat exchanger; the exhaust port of the low-pressure cylinder supplies steam to the external medium-temperature steam load.

[0014] Furthermore, during the winter heating season, when the low-pressure cylinder return steam and part of the high-temperature steam after heat release and cooling in the high-temperature heat storage heat exchanger return to the steam boiler, the heating medium on the opposite side is heated by the heating heat exchanger, and the heating medium is heated to the outside through the exhaust port.

[0015] Furthermore, in mode three, all the high-temperature steam produced by the steam boiler is supplied to the high-pressure cylinder, the output of the extraction back steam turbine is increased, and the high-pressure cylinder supplies steam to the external high-temperature steam load through the high-temperature steam extraction port; the compressed air stored in the gas storage reservoir is released, and after the air heater absorbs heat and heats up, it is expanded by the air expander to do work, so as to drive the auxiliary generator to output electricity; the high-temperature heat storage medium stored in the first high-temperature heat accumulator is successively heat-released and cooled by the air heater and the heat medium water vapor generator, and the steam after heat release and cooling enters the second high-temperature heat accumulator for storage; the heat medium water part of the medium-temperature heat accumulator is driven by the first medium-temperature circulation pump to enter the heat medium water vapor generator to absorb heat and heat up to become medium-temperature steam, and supply steam to the external medium-temperature steam load; the remaining heat medium water in the medium-temperature heat accumulator is driven by the second medium-temperature circulation pump to replace part or all of the external make-up water and mix with the exhaust steam of the low-pressure cylinder and then return to the steam boiler to increase the return water / return steam temperature of the steam boiler.

[0016] Furthermore, during the winter heating season, the medium-temperature heat storage device provides external heating through the third outlet.

[0017] The beneficial effects of the present invention are:

[0018] 1. By configuring a high-temperature heat storage module, thermal-electric decoupling of the thermal power generating unit is achieved, thereby ensuring the stable operation of the steam boiler while enhancing the unit's deep peak-shaving capability. By absorbing off-peak power from the grid through air compression or directly consuming the output power of the thermal power unit, the overall deep peak-shaving capability of the system is further improved.

[0019] 2. Synchronous power generation by the pumped-back thermal power generation module and the compressed air energy storage power generation module can improve the peak power generation capacity of the entire system. At the same time, the switching between steam extraction heating from the pumped-back thermal power generation module and steam generation heating from the high-temperature heat storage module can meet the demand for stable heat energy supply for steam loads.

[0020] 3. By recovering and utilizing the compressed heat energy in the compressed air energy storage power generation module and utilizing the waste heat of low-temperature exhaust steam from the back-extraction thermal power generation module, winter heating needs can be met. During periods when heating is not required, the compressed heat energy and low-temperature exhaust steam are directly supplied to the steam boiler to avoid wasting low-grade thermal energy in the system.

[0021] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is a structural block diagram of the energy storage-based thermal power generation system of the present invention;

[0025] Figure 2 This is a structural block diagram of Mode 1 of the energy storage-based thermal power unit cogeneration system of the present invention;

[0026] Figure 3 This is the structural framework of the second mode of the thermal power unit cogeneration system based on energy storage of the present invention. Figure 1 ;

[0027] Figure 4 This is the structural framework of the second mode of the thermal power unit cogeneration system based on energy storage of the present invention. Figure 2 ;

[0028] Figure 5 It is a structural block diagram of Mode 3 of the energy storage-based thermal power unit cogeneration system of the present invention.

[0029] In the picture:

[0030] Back-type thermal power generation module 1, steam boiler 11, back-type steam turbine 12, high-pressure cylinder 121, low-pressure cylinder 122, high-temperature heat storage module 2, high-temperature heat storage heat exchanger 21, first high-temperature heat accumulator 22, first high-temperature circulation pump 23, air heater 24, heat medium water vapor generator 25, second high-temperature heat accumulator 26, second high-temperature circulation pump 27, compressed air energy storage power generation module 3, air compressor 31, air cooler 32, air storage 33, air expander 34, medium-temperature heat accumulator 4, first medium-temperature circulation pump 5, second medium-temperature circulation pump 6, heating heat exchanger 7. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] Example 1

[0033] Figure 1 This is a structural block diagram of the energy storage-based thermal power generation system of the present invention;

[0034] like Figure 1 As shown, this embodiment provides a thermal power generation system based on energy storage, including: a pumped-back thermal power generation module 1, a high-temperature heat storage module 2, and a compressed air energy storage power generation module 3; the pumped-back thermal power generation module 1 includes: a steam boiler 11, a pumped-back steam turbine 12; the high-temperature heat storage module 2 includes: a high-temperature heat storage heat exchanger 21, a first high-temperature heat accumulator 22, a first high-temperature circulation pump 23, an air heater 24, a heat medium water vapor generator 25, a second high-temperature heat accumulator 26, and a second high-temperature circulation pump 27 arranged in series; the compressed air energy storage power generation module 3 includes: an air compressor 31, an air cooler 32, an air storage reservoir 33, an air heater 2 arranged in series 4. Air expander 34; the back-drawn thermal power generation module 1 heats the high-temperature heat storage module 2 through the high-temperature heat storage heat exchanger 21; the high-temperature heat storage module 2 heats the air intake of the air expander 34 in the compressed air energy storage power generation module 3 through the air heater 24; the compressed air energy storage power generation module 3 provides the steam boiler 11 water preheating for the back-drawn thermal power generation module 1 through the air cooler 32; the back-drawn thermal power generation module 1 operates independently in a cycle to form mode one; the back-drawn thermal power generation module 1 and the high-temperature heat storage module 2 and / or the compressed air energy storage power generation module 3 operate jointly to form mode two; the back-drawn thermal power generation module 1, the high-temperature heat storage module 2 and the compressed air energy storage power generation module 3 operate jointly to form mode three.

[0035] Among them, mode one refers to the conventional operating mode under non-deep peak regulation and peak operating conditions, that is, the operating mode under the rated operating parameters of the pumped-back steam turbine; mode two refers to the deep peak regulation operation mode, that is, due to the large peak-to-valley difference in the power grid load, the thermal power plants reduce their output and the generator sets exceed the basic peak regulation range for peak regulation; mode three refers to the electric thermal peak operation mode, that is, in the power system, due to the increase in electricity demand, the power supply becomes tense.

[0036] By configuring the high-temperature heat storage module 2, thermal-electric decoupling of the thermal power generating set is achieved, while the deep peak-shaving capability of the set is enhanced; by absorbing the valley electricity of the grid or directly consuming the output power of the thermal power generating set through the compressed air energy storage power generation module 3, the deep peak-shaving capability of the system as a whole is further improved; by synchronously generating electricity through the back-drawn thermal power generation module 1 and the compressed air energy storage power generation module 3, the peak power generation capacity of the system as a whole can be improved.

[0037] In this embodiment, the energy storage-based thermal power unit cogeneration system also includes: a medium-temperature heat accumulator 4; the inlet of the medium-temperature heat accumulator 4 is connected to the low-temperature side outlet of the air cooler 32; the first outlet of the medium-temperature heat accumulator 4 is connected to the low-temperature side inlet of the heat medium water vapor generator 25 through the first medium-temperature circulation pump 5; the low-temperature side outlet of the heat medium water vapor generator 25 is connected to the external medium-temperature steam load; the second outlet of the medium-temperature heat accumulator 4 is connected to the inlet of the steam boiler 11 through the second medium-temperature circulation pump 6; the third outlet of the medium-temperature heat accumulator 4 is connected to the external low-temperature heating load.

[0038] In this embodiment, the high-temperature thermal storage module 2 uses binary molten salt as the thermal storage medium. The operating temperature of the first high-temperature thermal storage unit 22 is set at 500°C, and the operating temperature of the second high-temperature thermal storage unit 26 is set at 290°C. The medium-temperature thermal storage unit 4 uses desalinated and deoxygenated heat transfer water as the thermal storage medium and is set to operate at 90°C.

[0039] In this embodiment, the energy storage-based thermal power unit cogeneration system also includes: a heating heat exchanger 7; the high-temperature side of the heating heat exchanger 7 is connected in series to the inlet of the steam boiler 11; and the low-temperature side of the heating heat exchanger 7 is connected to the external low-temperature heating load.

[0040] Optionally, the back-drawn steam turbine 12 includes a high-pressure cylinder 121 and a low-pressure cylinder 122; the first outlet of the steam boiler 11 is connected to the inlet of the high-pressure cylinder 121; and the second outlet of the steam boiler 11 is connected to the high-temperature side inlet of the high-temperature heat storage heat exchanger 21. The back-drawn steam turbine 12 of this embodiment has a dual-cylinder structure with a high-pressure cylinder 121 and a low-pressure cylinder 122. In practical applications, it can also be used in high-, medium-, and low-pressure multi-cylinder back-drawn steam turbine units.

[0041] In this embodiment, the high-temperature side outlet of the high-temperature heat storage heat exchanger 21 is connected to the external high-temperature steam load.

[0042] In this embodiment, the high-pressure cylinder 121 is connected to an external high-temperature steam load through a high-temperature steam extraction port.

[0043] In this embodiment, the exhaust port of the low-pressure cylinder 122 is connected to an external medium-temperature steam load.

[0044] In this embodiment, two sets of high-temperature steam interfaces A1 / A2, medium-temperature steam interfaces B1 / B2, and low-temperature heating interfaces C1 / C2 are provided. High-temperature steam interface A1 is the exhaust or intermediate-stage steam extraction port for high-pressure cylinder 121, while high-temperature steam interface A2 is the high-temperature side exhaust port for high-temperature heat storage heat exchanger 21. Medium-temperature steam interface B1 is the exhaust or intermediate-stage steam extraction port for low-pressure cylinder 122, while medium-temperature steam interface B2 is the low-temperature side exhaust port for heat medium water vapor generator 25. Low-temperature heating interface C1 is the low-temperature side outlet of heating heat exchanger 7, while low-temperature heating interface C2 is the third outlet of medium-temperature heat accumulator 4. The high-temperature steam output parameters of the high-temperature steam interface are set to 480°C / 4.8MPa, the medium-temperature steam output parameters of the medium-temperature steam interface are set to 280°C / 1.0MPa, and the heating medium water parameters of the low-temperature heating interface are set to 90°C / 0.4MPa.

[0045] Among them, under standard operating conditions, external heating is achieved through the A1 interface, B1 interface, and C1 interface; under deep peak-shaving operation mode, external heating is achieved through the A2 interface, B1 interface, and C1 interface; under electric peak operation mode, external heating is achieved through the A1 interface, B2 interface, and C2 interface. While ensuring the stability of heating supply, deep peak-shaving or peak thermal power supply is achieved through energy storage.

[0046] The energy storage-based cogeneration system of the thermal power unit in this embodiment can not only increase the peak-shaving depth and peak capacity of the back-drawn thermal power generation module 1, but also meet the stable co-supply of high-temperature and low-temperature steam, and meet the periodic heating guarantee needs of residents.

[0047] Example 2

[0048] Figure 2 This is a structural block diagram of Mode 1 of the energy storage-based thermal power unit cogeneration system of the present invention;

[0049] like Figure 2 As shown, this embodiment 2 provides a working method of a thermal power unit cogeneration system based on energy storage, including: in mode 1, the steam boiler 11 supplies high-temperature steam to the high-pressure cylinder 121 by heating external make-up water and exhausting steam from the low-pressure cylinder 122, so as to drive the back-type steam turbine 21 and its affiliated generator; the high-pressure cylinder 121 supplies steam to the external high-temperature steam load through the high-temperature steam extraction port; and the exhaust port of the low-pressure cylinder 122 supplies steam to the external medium-temperature steam load.

[0050] Specifically, under standard operating conditions, the back-drawn thermal power generation module 1 operates in an independent cycle; the steam boiler 11 supplies high-temperature steam to the high-pressure cylinder 121 by heating external make-up water and exhausting the low-pressure cylinder 122, driving the back-drawn steam turbine 12 and its affiliated generator to realize power supply; at the same time, high-temperature steam is extracted from the A1 interface of the high-pressure cylinder 121 and supplied to the outside, and medium-temperature steam is extracted from the B1 interface of the low-pressure cylinder 122 and supplied to the outside; in addition, if it enters the winter heating season, when the return steam from the low-pressure cylinder 122 and part of the high-temperature steam after heat release and cooling in the high-temperature heat storage heat exchanger 21 return to the steam boiler 11, they first heat the heating medium on the opposite side through the heating heat exchanger 7, and the heating medium is then heated to the outside through the C1 interface.

[0051] Figure 3 This is the structural framework of the second mode of the thermal power unit cogeneration system based on energy storage of the present invention. Figure 1 ;like Figure 3 As shown, in mode 2, part of the high-temperature exhaust steam of the steam boiler 11 enters the high-temperature side of the high-temperature heat storage heat exchanger 21 to heat the high-temperature heat storage medium in the second high-temperature heat accumulator 27. The high-temperature heat storage medium absorbs heat and is heated up before being stored in the first high-temperature heat accumulator 22. The high-temperature steam after the high-temperature heat storage heat exchanger 21 releases heat and cools down is supplied to the external high-temperature steam load through the high-temperature side outlet, and the remaining high-temperature steam returns to the steam boiler 11 through the heating heat exchanger 7. The exhaust port of the low-pressure cylinder 122 supplies steam to the external medium-temperature steam load.

[0052] Specifically, in the deep peak regulation operation mode, the extraction-type thermal power generation module 1 is operated in conjunction with the high-temperature heat storage module 2 and / or the compressed air energy storage power generation module 3; a portion of the high-temperature exhaust gas of the steam boiler 11 is extracted to enter the high-temperature side of the high-temperature heat storage heat exchanger 21 to heat the high-temperature heat storage medium from the second high-temperature heat accumulator 27, and the high-temperature heat storage medium absorbs heat and heats up before entering the first high-temperature heat accumulator 22 for storage. The high-temperature steam after heat release and cooling is supplied to the outside through the A2 interface according to the external load demand, and the rest is returned to the steam boiler 11 through the heating heat exchanger 7 for reheating; since the steam supply of the steam boiler 11 is partially extracted, it enters the high-pressure cylinder 1 The amount of high-temperature steam in the high-pressure cylinder 121 is reduced, which leads to a decrease in the working steam volume and output of the high-pressure cylinder 121 and the low-pressure cylinder 122, thereby achieving deep peak regulation; in this mode, the high-pressure cylinder 121 no longer supplies high-temperature steam to the outside through the A1 interface, and the low-pressure cylinder 122 continues to supply medium-temperature steam to the outside through the B1 interface to meet the stable supply demand of medium-temperature steam; in addition, if the winter heating season comes, the return steam from the low-pressure cylinder 122 and part of the high-temperature steam after heat release and cooling in the high-temperature heat storage heat exchanger 21 return to the steam boiler 11, firstly heat the heating medium on the opposite side through the heating heat exchanger 7, and the heating medium is heated to the outside through the C1 interface.

[0053] Figure 4 This is the structural framework of the second mode of the thermal power unit cogeneration system based on energy storage of the present invention. Figure 2 ;

[0054] like Figure 4 As shown, if the grid needs further reverse peak regulation, that is, if it needs to absorb more grid power, air compressor 31 is activated to compress ambient air for storage in gas storage reservoir 33. During this process, the high-temperature exhaust gas from air compressor 31 is first cooled by air cooler 32, where it is then heated by the heat medium water from the external water source and then stored in medium-temperature heat accumulator 4. Air compressor 31 can be powered by the grid or directly by the back-type steam turbine 12 or its associated generator.

[0055] Figure 5 It is a structural block diagram of Mode 3 of the energy storage-based thermal power unit cogeneration system of the present invention.

[0056] like Figure 5 As shown, in mode 3, all the high-temperature steam produced by the steam boiler 11 is supplied to the high-pressure cylinder 121, and the output of the back-type steam turbine 21 is increased. The high-pressure cylinder 121 supplies steam to the external high-temperature steam load through the high-temperature steam extraction port; the compressed air stored in the gas storage reservoir 33 is released, and after the air heater 24 absorbs heat and heats up, it is expanded by the air expander 34 to do work, thereby driving the auxiliary generator to output electricity; the high-temperature heat storage medium stored in the first high-temperature heat accumulator 22 is sequentially supplied by the air heater 24, the heat medium water vapor generator 2 5 releases heat and cools down, with the steam entering the second high-temperature heat accumulator 26 for storage. Driven by the first medium-temperature circulating pump 5, the heat medium water portion of the medium-temperature heat accumulator 4 enters the heat medium water steam generator 25, where it absorbs heat and heats up to become medium-temperature steam, which is then supplied to the external medium-temperature steam load. Driven by the second medium-temperature circulating pump 6, the remaining heat medium water in the medium-temperature heat accumulator 4 replaces part or all of the external make-up water, mixes with the exhaust steam from the low-pressure cylinder 122, and returns to the steam boiler 11, thereby raising the return water / return steam temperature of the steam boiler 11. During the winter heating season, the medium-temperature heat accumulator 4 provides external heating through the third outlet.

[0057] Specifically, in the electric heating peak operation mode, the pumped-back thermal power generation module 1, the high-temperature heat storage module 2 and the compressed air energy storage power generation module 3 operate jointly; the high-temperature steam produced by the steam boiler 11 is all supplied to the high-pressure cylinder 121, and further all supplied to the low-pressure cylinder 122, so that the output of the pumped-back steam turbine 12 is improved to meet the peak demand. At the same time, the high-pressure cylinder 121 supplies high-temperature steam to the outside through the A1 interface; if it is the winter heating season, the heating heat exchanger 7 no longer supplies external heating through the interface C1 to increase the return water / return air temperature of the steam boiler 1; the gas storage reservoir 33 releases the stored compressed air, and after the air heater 24 absorbs heat and heats up, it enters the air expander 34 to expand and do work and drive the auxiliary generator to output electricity, further providing peak power to the power grid; at the same time, the first high-temperature heat accumulator The high-temperature heat storage medium stored in 22 enters the air heater 24 under the drive of the first high-temperature circulation pump 23 to release heat and cool down, and then enters the heat medium water vapor generator 25 to further release heat and cool down, and finally returns to the second high-temperature heat accumulator 26 for storage; the heat medium water stored in the medium-temperature heat accumulator 4 enters the heat medium water vapor generator 25 under the drive of the first medium-temperature circulation pump 5 to absorb heat and heat up to become medium-temperature steam, and is supplied to the outside through the B2 interface; if it is the winter heating season, the medium-temperature heat accumulator 4 provides external heating through the C2 interface; the remaining heat medium water in the medium-temperature heat accumulator 4 is driven by the second medium-temperature circulation pump 6 to replace part or all of the external make-up water and mix with the exhaust steam of the low-pressure cylinder 122 and then return to the steam boiler 11, thereby increasing the return water / return steam temperature of the steam boiler 11, and then increasing its steam production.

[0058] In summary, the energy storage-based cogeneration system and method of the thermal power unit of the present invention realizes the thermoelectric decoupling of the pumped-back thermal power generation module 1 by configuring the high-temperature heat storage module 2, thereby enhancing the deep peak-shaving capability of the unit while ensuring the stable operation of the steam boiler 11; by absorbing the grid valley electricity or directly consuming the output power of the pumped-back thermal power generation module 1 through air compression, the deep peak-shaving capability of the system as a whole is further improved. By generating electricity at full load by the pumped-back thermal power generation module 1 and generating electricity synchronously with the compressed air energy storage power generation module 3, the peak power generation capacity of the system as a whole can be improved; by switching between steam extraction for heating by the pumped-back thermal power generation module 1 and steam generation for heating by the high-temperature heat storage module 2, the demand for stable heat energy supply of the steam load can be met; by recycling the compressed heat energy of the compressed air energy storage power generation module 3 and utilizing the waste heat of the low-temperature exhaust steam of the pumped-back thermal power generation module 1, the winter heating demand can be met. During the period when heating is not required, the compressed heat energy and low-temperature exhaust steam are directly supplied to the steam boiler 11, avoiding the waste of low-grade heat energy in the system.

[0059] The various devices selected in this application (components whose specific structures are not described) are all universal standard parts or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0060] In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0061] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0062] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A thermal power cogeneration system based on energy storage, characterized in that: include: A pumped-back thermal power generation module (1), a high-temperature heat storage module (2), and a compressed air energy storage power generation module (3); The back-drawn thermal power generation module (1) comprises a steam boiler (11); The high-temperature heat storage module (2) comprises: a high-temperature heat storage heat exchanger (21), an air heater (24), and a heat medium water vapor generator (25); The compressed air energy storage power generation module (3) comprises: an air cooler (32) and an air expander (34); The back-type thermal power generation module (1) heats the high-temperature heat storage module (2) via the high-temperature heat storage heat exchanger (21); The high-temperature heat storage module (2) heats the air intake of the air expander (34) in the compressed air energy storage power generation module (3) through the air heater (24); The compressed air energy storage power generation module (3) provides water preheating of the steam boiler (11) for the pumped-back thermal power generation module (1) through the air cooler (32); The back-drawn thermal power generation module (1) operates independently in a cycle to form mode one; the back-drawn thermal power generation module (1) operates in conjunction with the high-temperature heat storage module (2) and / or the compressed air energy storage power generation module (3) to form mode two; and the back-drawn thermal power generation module (1), the high-temperature heat storage module (2) and the compressed air energy storage power generation module (3) operate in conjunction to form mode three.

2. The thermal power cogeneration system based on energy storage according to claim 1, characterized in that: The back-extracted thermal power generation module (1) further comprises: a back-extracted steam turbine (12); The pumped-back steam turbine (12) comprises: a high-pressure cylinder (121) and a low-pressure cylinder (122); The first outlet of the steam boiler (11) is connected to the inlet of the high-pressure cylinder (121); The second outlet of the steam boiler (11) is connected to the high-temperature side inlet of the high-temperature heat storage heat exchanger (21); The high-temperature side outlet of the high-temperature heat storage heat exchanger (21) is connected to an external high-temperature steam load; The high-pressure cylinder (121) is connected to an external high-temperature steam load via a high-temperature steam extraction port; The exhaust port of the low-pressure cylinder (122) is connected to an external medium-temperature steam load; The return steam from the low-pressure cylinder (122) is cooled by a heating heat exchanger (7) and then flows back to the steam boiler (11); The low-temperature side of the heating heat exchanger (7) is connected to an external low-temperature heating load.

3. The thermal power cogeneration system based on energy storage according to claim 2, characterized in that: The high-temperature heat storage module (2) further comprises: a first high-temperature heat accumulator (22), a first high-temperature circulation pump (23), a second high-temperature heat accumulator (26), and a second high-temperature circulation pump (27); The high-temperature heat storage heat exchanger (21), the first high-temperature heat storage tank (22), the first high-temperature circulation pump (23), the air heater (24), the heat medium water vapor generator (25), the second high-temperature heat storage tank (26), and the second high-temperature circulation pump (27) are arranged in a circular manner.

4. The thermal power cogeneration system based on energy storage according to claim 3, characterized in that: The compressed air energy storage power generation module (3) further comprises: an air compressor (31) and an air storage reservoir (33); The air compressor (31), air cooler (32), air storage (33), air heater (24), and air expander (34) are sequentially arranged in series.

5. The thermal power cogeneration system based on energy storage according to claim 4, characterized in that: The energy storage-based thermal power unit cogeneration system further includes: a medium-temperature heat accumulator (4); The inlet of the medium-temperature heat accumulator (4) is connected to the low-temperature side outlet of the air cooler (32); The first outlet of the medium-temperature heat accumulator (4) is connected to the low-temperature side inlet of the heat medium water vapor generator (25) via a first medium-temperature circulation pump (5); The low-temperature side outlet of the heat medium steam generator (25) is connected to an external medium-temperature steam load; The second outlet of the medium-temperature heat accumulator (4) is connected to the inlet of the steam boiler (11) through a second medium-temperature circulation pump (6); The third outlet of the medium-temperature heat accumulator (4) is connected to an external low-temperature heating load.

6. A method for operating a thermal power unit cogeneration system based on energy storage, characterized in that: include: In mode 1, the steam boiler (11) heats external feed water and exhaust steam from the low-pressure cylinder (122) to supply high-temperature steam to the high-pressure cylinder (121) to drive the back-type steam turbine (21) and its attached generator; The high-pressure cylinder (121) supplies steam to an external high-temperature steam load through a high-temperature steam extraction port; The exhaust port of the low-pressure cylinder (122) supplies steam to the external medium-temperature steam load.

7. The operating method of the energy storage-based thermal power cogeneration system according to claim 6, characterized in that: In mode 2, part of the high-temperature exhaust steam of the steam boiler (11) enters the high-temperature side of the high-temperature heat storage heat exchanger (21) to heat the high-temperature heat storage medium of the second high-temperature heat storage unit (27). The high-temperature heat storage medium absorbs heat and is heated before being stored in the first high-temperature heat storage unit (22). The high-temperature steam after the high-temperature heat storage heat exchanger (21) releases heat and cools down is supplied to the external high-temperature steam load through the high-temperature side outlet, and the remaining high-temperature steam is returned to the steam boiler (11) through the heating heat exchanger (7); The exhaust port of the low-pressure cylinder (122) supplies steam to the external medium-temperature steam load.

8. The operating method of the energy storage-based thermal power cogeneration system according to claim 6 or 7, characterized in that: During the winter heating season, part of the high-temperature steam after the return steam from the low-pressure cylinder (122) and the high-temperature heat storage heat exchanger (21) releases heat and cools down returns to the steam boiler (11), and heats the heating medium on the opposite side through the heating heat exchanger (7), and the heating medium is heated to the outside through the exhaust port.

9. The operating method of the energy storage-based thermal power generation system according to claim 6, characterized in that: In mode three, all the high-temperature steam produced by the steam boiler (11) is supplied to the high-pressure cylinder (121), the output of the back-extraction steam turbine (21) is increased, and the high-pressure cylinder (121) supplies steam to the external high-temperature steam load through the high-temperature steam extraction port; The compressed air stored in the gas storage (33) is released, and after being heated by the air heater (24), it is expanded by the air expander (34) to produce work, thereby driving the auxiliary generator to output electricity. The high-temperature heat storage medium stored in the first high-temperature heat accumulator (22) is sequentially cooled by the air heater (24) and the heat medium water vapor generator (25), and the steam after the heat release and cooling enters the second high-temperature heat accumulator (26) for storage; The heat medium water portion of the medium temperature heat accumulator (4) is driven by the first medium temperature circulation pump (5) to enter the heat medium water steam generator (25) to absorb heat and heat up to become medium temperature steam, and then supply steam to the external medium temperature steam load; The remaining heat medium water in the medium temperature heat accumulator (4) is driven by the second medium temperature circulation pump (6) to replace part or all of the external make-up water and is mixed with the exhaust steam of the low pressure cylinder (122) and then returned to the steam boiler (11) to increase the return water / return steam temperature of the steam boiler (11).

10. The operating method of the energy storage-based thermal power cogeneration system according to claim 9, characterized in that: During the winter heating season, the medium-temperature heat accumulator (4) provides external heating through the third outlet.

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