Energy storage heating and heat supply energy system suitable for electric power spot transaction

Abstract

The invention relates to the technical field of energy utilization, in particular to an energy storage heating and heat supply energy system suitable for electric power spot transaction, which comprises a unit module, a first-stage heating module, a second-stage heating module, a third-stage heating module and a fourth-stage heating module, the second-stage heating module comprises a heating water return pipe, a heating water drainage pipe, an electric heating pump, a low-pressure cylinder drain pipe and an auxiliary circuit; the heat storage module comprises a heat storage water tank; the heating water return pipe is provided with two paths, one path is communicated with the condenser, the other path is communicated with the heating water drainage pipe, the heating water drainage pipe is communicated with the condenser, the heating water drainage pipe is further communicated with the electric heating pump, and the electric heating pump is communicated with the heat storage water pool. By arranging the first-stage heating module, the second-stage heating module and the cross-season heat storage water pool, gradient utilization of exhaust steam of the low-pressure cylinder can be achieved, and therefore under the condition that the electric load is determined, the heat supply load outside the unit can fluctuate between 0% and 300%, and the lowest external power supply load of the straight condensing unit can be reduced to 10% THA.

Description

Technical Field

[0001] The present invention relates to the technical field of energy utilization, and in particular to an energy storage heating system suitable for spot electricity trading. Background Art

[0002] High back pressure heating means increasing the pressure of the exhaust steam in the condenser and using circulating water from the heat network to cool the exhaust steam, thereby using the latent heat of vaporization of the exhaust steam from the steam turbine unit to heat the circulating water and achieve heating. This technology has low heating energy consumption, but has the following disadvantages: (1) Strong coupling between heat and electricity and poor operational flexibility. When the heat supply is constant, the electrical load regulation capacity is less than 5%; (2) High requirements for the operational stability of the heat network. When the circulating water from the heat network leaks, it may lead to insufficient cooling water for the unit and an increase in the exhaust steam temperature, thereby threatening the safe operation of the unit.

[0003] Both the medium- and low-pressure interconnecting pipe heating and the low-pressure cylinder zero-output heating technology use the medium-pressure cylinder exhaust steam to heat the circulating water of the heat network. Under this method, the unit operation flexibility is greater, but the energy quality of the medium-pressure cylinder exhaust steam is relatively high. If it is directly used to heat the circulating water of the heat network, there will be a loss of work capacity and high heating energy consumption. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] In view of the above-mentioned problems that high back pressure heating has low energy consumption but weak flexibility, and medium pressure cylinder exhaust steam heating has high energy consumption, the present invention is proposed.

[0006] Therefore, the object of the present invention is to provide an energy storage heating system that is suitable for spot electricity trading.

[0007] To solve the above technical problems, the present invention provides the following technical solutions: a storage heating energy system suitable for spot electricity trading, including a unit module, and also a primary heating module, including a condenser and a condensate pump; a secondary heating module, including a heating return pipe, a heating drain pipe, an electric heating pump, a low-pressure cylinder drain pipe and a plant circuit; a heat storage module, including a hot water storage tank; the heating return pipe is provided with two paths, one path is connected to the condenser, and the other path is connected to the heating drain pipe, the heating drain pipe is connected to the condenser, the heating drain pipe is also connected to the electric heating pump, and the electric heating pump is connected to the hot water storage tank.

[0008] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, the unit module includes a medium-pressure cylinder, a low-pressure cylinder, a generator and a steam supply pipeline, the medium-pressure cylinder, the low-pressure cylinder and the generator are coaxially arranged, and the medium-pressure cylinder is connected to the low-pressure cylinder through a steam supply pipeline.

[0009] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, the exhaust end of the low-pressure cylinder is connected to the input end of the condenser, the output end of the condenser is connected to the condensate pump, and the output end of the condensate pump is connected to the condensate discharge pipe.

[0010] As a preferred solution of the energy storage heating and heat supply system adapted to spot electricity trading described in the present invention, the heating return water pipe is connected with the external heating return water, the path 1 of the heating return water pipe inputs the condenser, the heating return water is discharged to the heating drain pipe after heating, and the path 2 of the heating return water pipe is connected with the heating drain pipe.

[0011] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, the electric heating pump is provided with a cold side and a hot side, the hot side is provided with two heaters, one of the heaters is driven by an external factory circuit, and the other heater is driven by a low-pressure cylinder drain pipe.

[0012] As a preferred solution of the energy storage heating and heat supply system adapted to spot electricity trading described in the present invention, the input end of the low-pressure cylinder drain pipe is connected to the low-pressure cylinder exhaust steam, the output end of the low-pressure cylinder drain pipe is connected to the hot side of the electric heating pump, and the hot side output end of the electric heating pump is connected to the condensate pump.

[0013] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, the heating drainage pipe is also divided into two paths, one path is directly discharged to the outside, and the other path is connected to the cold side of the electric heating pump.

[0014] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, the heat storage module also includes a water supply pipeline and a heating pipeline, the water supply pipeline is connected to the input end of the heat storage tank, and the heating pipeline is connected to the external heating water supply.

[0015] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, a second regulating valve, a second check valve, a third regulating valve and a third isolating valve are provided on the heating return pipe.

[0016] As a preferred solution of the energy storage heating system adapted to spot electricity trading described in the present invention, a first check valve, a first regulating valve and a first isolation valve are arranged on the low-pressure cylinder drain pipe.

[0017] Beneficial effects of the present invention: The present invention can realize step-by-step utilization of low-pressure cylinder exhaust steam by setting a primary heating module and a secondary heating module and a cross-seasonal heat storage tank, thereby achieving;

[0018] (1) For conventional high back pressure units, when the electric load is determined, the fluctuation degree of the heat load generally does not exceed 5%. Under the scheme of the present invention, when the electric load is determined, the external heat supply load of the unit can fluctuate between 0 and 300%.

[0019] (2) In the non-heating season, the minimum external power supply load of a conventional pure condensing unit is generally 30% THA; under the present invention, the minimum external power supply load of a pure condensing unit can be reduced to 10% THA.

[0020] (3) It can realize flexible power quotation and flexible operation adjustment of units under power spot trading, thereby achieving a significant increase in power spot trading revenue.

[0021] (4) When the electrical load of the unit fluctuates greatly during the heating season, the residential heating heat load is output stably. In the non-heating season, heat can be stored in the heat storage tank to reduce the external power supply load of the auxiliary unit, and the heat stored in the non-heating season can be used for the heating needs of residents in the heating season. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0023] Figure 1 It is an overall schematic diagram of an energy storage heating system suitable for spot electricity trading.

[0024] Figure 2 The present invention is a judgment flow chart of an energy storage heating system suitable for spot electricity trading. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0028] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0029] Example 1

[0030] Reference Figure 1-Figure 2 , which is the first embodiment of the present invention, and provides an energy storage heating system suitable for spot electricity trading, including a unit module 100, and also including a primary heating module 200, including a condenser 201 and a condensate pump 202; a secondary heating module 300, including a heating return pipe 301, a heating drainage pipe 302, an electric heating pump 303, a low-pressure cylinder 102 drain pipe and a plant circuit 305; a heat storage module 400, including a hot water storage tank 402; the heating return pipe 301 is provided with two paths, one path is connected to the condenser 201, and the other path is connected to the heating drainage pipe 302, the heating drainage pipe 302 is connected to the condenser 201, the heating drainage pipe 302 is also connected to the electric heating pump 303, and the electric heating pump 303 is connected to the hot water storage tank 402.

[0031] Specifically, the unit module 100 includes an intermediate pressure cylinder 101, a low pressure cylinder 102, a generator 103 and a steam supply pipeline 104. The intermediate pressure cylinder 101, the low pressure cylinder 102 and the generator 103 are coaxially arranged. The intermediate pressure cylinder 101 and the low pressure cylinder 102 are connected through the steam supply pipeline 104. A regulating valve is provided on the steam supply pipeline 104 for adjusting the steam flow rate. The intermediate pressure cylinder 101 and the low pressure cylinder 102 generate electricity by doing work through steam expansion.

[0032] Furthermore, the exhaust end of the low-pressure cylinder 102 is connected to the input end of the condenser 201, the output end of the condenser 201 is connected to the condensate pump 202, and the output end of the condensate pump 202 is connected to the condensate discharge pipe 203. The low-pressure exhaust steam enters the condenser 201 and is condensed and then discharged through the condensate pump 202.

[0033] Furthermore, the heating return water pipe 301 is connected with the external heating return water. Path 1 of the heating return water pipe 301 inputs the condenser 201, and the heating return water is discharged to the heating drain pipe 302 after being heated. Path 2 of the heating return water pipe 301 is connected with the heating drain pipe 302. The external heating return water can enter the condenser 201 through the heating return water pipe 301, and the heating return water is preliminarily heated by low-pressure exhaust steam. The heated heating return water is discharged to the outside through the heating drain pipe 302. The heating return water can also not enter the condenser 201, but directly merge into the heating drain pipe 302.

[0034] Furthermore, the electric heating pump 303 is provided with a cold side and a hot side, and the hot side is provided with two heaters, one heater is driven by an external factory circuit 305, and the other heater is driven by a drain pipe of the low-pressure cylinder 102. The heating drainage after preliminary heating can enter the electric heating pump 303 through the heating drainage pipe 302 for further heating. The electric heating pump 303 can utilize the exhaust steam of the low-pressure cylinder 102 for heating or utilize electricity for heating.

[0035] Furthermore, the input end of the low-pressure cylinder 102 drain pipe is connected to the exhaust steam of the low-pressure cylinder 102, the output end of the low-pressure cylinder 102 drain pipe is connected to the hot side of the electric heating pump 303, the hot side output end of the electric heating pump 303 is connected to the condensate pump 202, and the low-pressure cylinder 102 drain pipe can allow the exhaust steam of the low-pressure cylinder 102 to bypass the condenser 201 and be introduced into the electric heating pump 303, thereby adjusting the external power supply load and heating heat load of the unit by adjusting the power consumption of the electric heating pump 303.

[0036] Furthermore, the heating drainage pipe 302 is also divided into two paths, one path is directly discharged to the outside, and the other path is connected to the cold side of the electric heating pump 303. The heating drainage pipe 302 can choose to send the heating return water for heating or directly discharge it to the outside.

[0037] Furthermore, the heat storage module 400 also includes a water supply pipeline 401 and a heating pipeline 403. The water supply pipeline 401 is connected to the input end of the heat storage tank 402, and the heating pipeline 403 is connected to the external heating water supply. The water supply pipeline 401 is used to send the water heated by the electric heating pump 303 into the heat storage tank 402. The heat storage tank 402 is used to store heat. In the heating season, the heat storage tank 402 stores or releases hot water to achieve a stable output of the residential heating heat load when the unit's electrical load fluctuates greatly. In the non-heating season, the heat storage tank 402 can be used to store heat to assist in reducing the external power supply load of the unit, and the heat stored in the non-heating season can be used for the heating needs of residents in the heating season.

[0038] Furthermore, the heating return pipe 301 is provided with a second regulating valve 301a, a second check valve 301b, a third regulating valve 301c and a third isolation valve 301d, the low-pressure cylinder 102 drain pipe is provided with a first check valve 304a, a first regulating valve 304b, a first isolation valve 304c, and the heating pipeline 403 is provided with a fourth regulating valve 403a and a fourth isolation valve 403b, and each valve is used to control water flow, steam flow and other data.

[0039] Example 2

[0040] Reference Figure 1-Figure 2 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that: during the heating season, the unit needs to operate in a high back pressure state and enter the heating season mode. At this time, the maximum heating capacity of the unit and the electric heating pump 303 and the external power supply load of the unit are obtained by calculation.

[0041] Specifically, the maximum heating supply of the unit is Qmax, the external power supply load of the unit is P, and the relationship between the maximum heating supply of the unit and the external power supply load of the unit is Qmax=f(P). When the power load is P, the relationship between the real-time load Q of the heat user and Qmax is determined.

[0042] The maximum heat supply Qmax is obtained through unit testing = maximum exhaust volume of low-pressure cylinder × (exhaust enthalpy value - drain enthalpy value after cooling). For different types of units, the maximum exhaust volume of low-pressure cylinder under electrical load P is different.

[0043] Furthermore, when Q is less than or equal to Qmax, the external heating return water enters the condenser 201 through the heating return water pipe 301 of path 1 and is heated to 75°C, and then enters the electric heating pump 303 through the heating drain pipe 302. The electric heating pump 303 heats the hot network water from 75°C to 100°C through electric drive and recovered turbine exhaust heat, and finally flows into the hot water storage tank 402 for storage. The heating pipeline 403 of the hot water storage tank 402 is partially opened through the fourth regulating valve 403a and the fourth isolation valve 403b to supply heat to the outside and store part of the surplus water.

[0044] Furthermore, when Q is greater than Qmax, the external heating return water enters the condenser 201 through the heating return water pipe 301 of path 1 and is heated to 75°C, and then enters the electric heating pump 303 through the heating drain pipe 302. The electric heating pump 303 heats the hot network water from 75°C to 100°C through electric drive and recovered turbine exhaust heat, and finally flows into the hot water storage tank 402 for storage. The heating pipeline 403 of the hot water storage tank 402 is opened more widely through the fourth regulating valve 403a and the fourth isolation valve 403b to release the hot water stored in the tank to meet the heating needs of heating users.

[0045] Furthermore, according to the requirements of deep regulation of the power grid, the electric heating pump 303 is turned on to reduce the external power supply load of the unit, and the heat storage tank 402 is used to adjust the heat load supply. During the variable load operation of the unit, the main steam flow of the turbine is adjusted, and the exhaust steam flow of the turbine changes accordingly; the external power supply load and the heating heat load of the unit are adjusted by adjusting the exhaust steam flow entering the first-level heating module 200 and the second-level heating module 300 and the power consumption of the electric heating pump 303 in the second-level heating module 300.

[0046] Example 3

[0047] Reference Figure 1-Figure 2 , which is the third embodiment of the present invention. This embodiment is different from the above embodiments in that: in the non-heating season, the unit operates in a conventional back pressure state, and the external heating return water directly enters the electric heating pump 303 through the heating return water pipe 301 of path 2, and is heated by the electric heating pump 303 and then flows into the hot water storage tank 402.

[0048] Furthermore, determine the relationship between the spot electricity trading price and the unit's power generation cost price.

[0049] Furthermore, when the spot electricity price is less than or equal to the power generation cost price of the unit, the secondary heating module 300 is turned on, and the electric heating pump 303 uses the power generated by the unit to supply electricity, reducing the external power supply load of the unit. The heating return water is heated by the electric heating pump 303 and stored in the heat storage tank 402, so as to store heat across seasons and be used for heating during the heating season.

[0050] Furthermore, when the spot electricity price is greater than the power generation cost price of the unit, the secondary heating module 300 is turned off, and the heating return water directly enters the heating drainage pipe 302 through the path 2 of the heating return water pipe 301, and then is discharged to the outside from the heating drainage pipe 302 without heating. The power generation of the unit is used to supply power to the outside.

[0051] The power plant can configure electric heat pumps according to actual production needs. It can be configured with heat pumps with a heating capacity of 50 to 200MW. When the electric heat pump heats 60MW, the electricity consumption is about 15MW. At this time, the external power supply load of the unit is reduced by 15MW. (The ratio of heating supply to electricity consumption is 4).

[0052] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and ratio of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of the execution function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0053] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0054] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, the development effort will be a routine task of design, fabrication, and production without undue experimentation.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. 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. An energy storage heating system suitable for electricity spot trading, comprising a unit module (100), Features: Also includes, The primary heating module (200) includes a condenser (201) and a condensate pump (202); The secondary heating module (300) includes a heating water return pipe (301), a heating drainage pipe (302), an electric heating pump (303), a low-pressure cylinder (102) drain pipe and a factory circuit (305); A heat storage module (400) includes a heat storage tank (402); The heating return water pipe (301) is provided with two paths, one path is connected to the condenser (201), and the other path is connected to the heating drainage pipe (302), the heating drainage pipe (302) is connected to the condenser (201), the heating drainage pipe (302) is also connected to the electric heating pump (303), and the electric heating pump (303) is connected to the hot water storage tank (402).

2. The energy storage heating system adapted to electricity spot trading as claimed in claim 1, Features: The unit module (100) comprises a medium-pressure cylinder (101), a low-pressure cylinder (102), a generator (103) and a steam supply pipeline (104); the medium-pressure cylinder (101), the low-pressure cylinder (102) and the generator (103) are coaxially arranged; the medium-pressure cylinder (101) and the low-pressure cylinder (102) are connected via the steam supply pipeline (104).

3. The energy storage heating system adapted to electricity spot trading as claimed in claim 2, Features: The exhaust end of the low-pressure cylinder (102) is connected to the input end of the condenser (201), the output end of the condenser (201) is connected to the condensate pump (202), and the output end of the condensate pump (202) is connected to the condensate discharge pipe (203).

4. The energy storage heating system adapted to electricity spot trading as claimed in claim 3, Features: The heating return water pipe (301) is connected to the external heating return water, and the path 1 of the heating return water pipe (301) is input into the condenser (201). The heating return water is discharged to the heating drainage pipe (302) after being heated, and the path 2 of the heating return water pipe (301) is connected to the heating drainage pipe (302).

5. The energy storage heating system adapted to electricity spot trading as claimed in claim 4, Features: The electric heating pump (303) is provided with a cold side and a hot side, and the hot side is provided with two heaters, one of the heaters is driven by an external factory circuit (305), and the other heater is driven by a low-pressure cylinder (102) drain pipe.

6. The energy storage heating system adapted to electricity spot trading as claimed in claim 5, Features: The input end of the low-pressure cylinder (102) drain pipe is connected to the exhaust steam of the low-pressure cylinder (102), the output end of the low-pressure cylinder (102) drain pipe is connected to the hot side of the electric heating pump (303), and the hot side output end of the electric heating pump (303) is connected to the condensate pump (202).

7. The energy storage heating system adapted to electricity spot trading as claimed in claim 6, Features: The heating drainage pipe (302) is also divided into two paths, one path is directly discharged to the outside, and the other path is connected to the cold side of the electric heating pump (303).

8. The energy storage heating system adapted to electricity spot trading as claimed in claim 7, Features: The heat storage module (400) further comprises a water supply pipeline (401) and a heating pipeline (403); the water supply pipeline (401) is connected to an input end of the heat storage tank (402); and the heating pipeline (403) is connected to external heating water supply.

9. The energy storage heating system adapted to electricity spot trading as claimed in claim 8, Features: The heating water return pipe (301) is provided with a second regulating valve (301a), a second check valve (301b), a third regulating valve (301c) and a third isolation valve (301d).

10. The energy storage heating system adapted to electricity spot trading as claimed in claim 9, Features: The drain pipe of the low-pressure cylinder (102) is provided with a first check valve (304a), a first regulating valve (304b), and a first isolation valve (304c).

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