New Energy Coupled Thermal Power Generation Energy Storage Peak Shaving Combined System and Operation Method

Abstract

New energy-coupled thermal power generation energy storage peak shaving combined system and operation method, comprising a solar power generation device, a wind power generation device, a lithium battery, a power station boiler, a high-pressure turbine, a low-pressure turbine, a generator, a low-temperature heater, a high-temperature heater and a power grid; the solar power generation device is divided into two paths, one path is connected to the lithium battery, and the other path is connected to the power grid; the wind power generation device is divided into two paths, one path is connected to the lithium battery, and the other path is connected to the power grid; the outlet of the power station boiler is sequentially connected to the high-pressure turbine and the low-pressure turbine, and the outlet of the low-pressure turbine is sequentially connected to the low-temperature heater and the high-temperature heater; the generator is connected to the low-pressure turbine; the output end of the generator is divided into two paths, one path is connected to the power grid, and the other path is connected to the lithium battery. In the case of sufficient and stable wind power generation or solar power generation, according to Solution 1: all the generated capacity is directly fed into the power grid for users to use. According to Solution 2: part of the power is input into the lithium battery through an inverter and the inverter for energy storage.

Description

Technical Field

[0001] The present invention belongs to the field of deep peak regulation of thermal power plants, and particularly relates to a combined system for peak regulation of power generation and energy storage coupled with a new energy thermal power unit and an operation method thereof. Background Art

[0002] Thermal power generation currently faces the risk of structural overcapacity, and renewable energy sources face immense pressure to absorb it. Thermal power generation will inevitably yield to renewable energy development. Thermal power units face significant peak load regulation. In the "Three Norths" region, the conflict between wind and heat is particularly acute during the heating season. The peak wind resource period coincides with the winter heating season. Furthermore, some provinces and regions have a high proportion of thermal power units and a relative shortage of other peak load sources. The combination of growing heating demand and increasing clean energy capacity has resulted in very limited peak load regulation capacity. In Northeast China in particular, the vast majority of thermal power generation consists of cogeneration units, with a peak load regulation capacity of only 10%. This impacts both the absorption of existing renewable energy resources and the development of new energy. This significant gap in peak load regulation capacity has led to severe new energy curtailment in some areas, forcing thermal power units to achieve significant peak load regulation through retrofitting.

[0003] Currently, units participating in deep peak regulation are operating off-design for extended periods, resulting in decreased safety and economic efficiency. Based on the technologies and retrofits implemented, these units face varying degrees of safety issues with boiler low-load stable combustion and hydrodynamic circulation, full-load operation of denitrification devices and low-load cooling of steam turbines, control system flexibility issues during prolonged low loads and rapid load changes, equipment operating cycle and lifespan degradation, and thermal-electrical decoupling of heating units. These issues all require further research and optimization. Summary of the Invention

[0004] The purpose of the present invention is to provide a new energy coupled thermal power generation unit energy storage peak regulation combined system and operation method to solve the above problems.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The new energy-coupled thermal power generation unit power generation, energy storage and peak-shaving combined system includes a solar power generation device, a wind power generation device, a lithium battery, a power station boiler, a high-pressure turbine, a low-pressure turbine, a generator, a low-temperature heater, a high-temperature heater and a power grid; the solar power generation device is divided into two paths, one connected to the lithium battery and the other connected to the power grid; the wind power generation device is divided into two paths, one connected to the lithium battery and the other connected to the power grid; the power station boiler outlet is connected to the high-pressure turbine and the low-pressure turbine in turn, and the low-pressure turbine outlet is connected to the low-temperature heater and the high-temperature heater in turn; the generator is connected to the low-pressure turbine; the generator output end is divided into two paths, one connected to the power grid and the other connected to the lithium battery.

[0007] Further, an electrode heating device is connected in parallel to the low-temperature heater and high-temperature heater circuits, and a fifth gate valve and a sixth gate valve are respectively arranged between the electrode heating device and the low-temperature heater and the high-temperature heater.

[0008] Further, the lithium battery is connected to the electrode heating device, and a third control switch is arranged in the middle.

[0009] Further, a first inverter and a first control switch are arranged between the solar power generation device and the lithium battery.

[0010] Further, a second inverter and a second control switch are arranged between the wind power generation device and the lithium battery.

[0011] Further, a condenser and a circulating pump are sequentially connected between the outlet of the low-pressure turbine and the low-temperature heater.

[0012] Further, a fourth inverter and a fourth control switch are arranged between the generator and the lithium battery; the lithium battery is connected to the power grid, and a third inverter is arranged in the middle.

[0013] Further, the high-pressure turbine is connected to the high-temperature heater, and the low-pressure turbine is connected to the low-temperature heater; gate valves are arranged at the inlet of the low-temperature heater, the outlet of the high-temperature heater, between the high-pressure turbine and the high-temperature heater, and between the low-pressure turbine and the low-temperature heater.

[0014] Further, an operation method of a new energy-coupled thermal power unit power generation energy storage peak shaving combined system includes the following steps:

[0015] When the wind power generation device or the solar power generation device is sufficient and stable, Scheme 1: All the power generation capacity is directly sent into the power grid for users to use; Scheme 2: Part of the electric energy is input into the lithium battery through the first inverter and the second inverter for energy storage.

[0016] When the wind power generation device or the solar power generation device is intermittent and unstable, the power generation in this period is also input into the lithium battery through the first inverter and the second inverter for energy storage. On the one hand, it avoids the impact on the power grid, and on the other hand, it makes full use of clean energy.

[0017] When the power generation capacity demand of the thermal power unit is large, the heat source of the regenerative system is taken from the electrode heater. The specific operation is as follows: Close the first gate valve, the second gate valve, the third gate valve, and the fourth gate valve, open the fifth gate valve and the sixth gate valve, and at the same time start the third control switch and the fourth control switch to ensure the smoothness of the discharge circuit and the boiler bypass feed water system; Utilize the electric energy stored in the lithium battery to heat the boiler return water through the electrode heating device, heat the boiler feed water to 250 °C, and increase the working medium temperature of the boiler return water system; Replace the steam extraction of the steam turbine, increase the power generation, and reduce the coal consumption.

[0018] When the power generation capacity demand of the thermal power unit is low and deep peak shaving is required, open the first gate valve, the second gate valve, the third gate valve, and the fourth gate valve, close the fifth gate valve and the sixth gate valve, start the steam extraction heating boiler return water system of the steam turbine, cut off the electrode heating system, and at the same time turn on the fourth energy storage control switch of the thermal power unit; on the one hand, reduce the power generation of the steam turbine and the power generation, and on the other hand, the excess power generation of the generator is stored in the lithium battery through the fourth inverter;

[0019] The electric energy stored in the lithium battery is directly transmitted to the power grid through the third inverter.

[0020] Compared with the prior art, the present invention has the following technical effects:

[0021] When the wind power generation or solar power generation is sufficient and stable, Scheme 1: All the power generation capacity is directly sent into the power grid for users to use. Scheme 2: Part of the electric energy is stored in the lithium battery through the inverter and the input of the inverter.

[0022] When the wind power generation or solar power generation is intermittent (unstable), the power generation during this period is also stored in the lithium battery through the inverter and the input of the inverter. On the one hand, it avoids the impact on the power grid, and on the other hand, it makes full use of clean energy.

[0023] When the power generation capacity demand of the thermal power unit is large, the heat source of the regenerative system is taken from the electrode heater. Utilize the electric energy stored in the lithium battery to heat the boiler return water through the electrode heating device, heat the boiler feed water to 250°C, and increase the working medium temperature of the boiler return water system. Instead of steam extraction of the steam turbine, it increases the power generation and reduces the coal consumption.

[0024] When the power generation capacity demand of the thermal power unit is low and deep peak shaving is required, start the steam extraction heating boiler return water system of the steam turbine, cut off the electrode heating system, and at the same time turn on the energy storage control switch of the thermal power unit. On the one hand, reduce the power generation of the steam turbine and the power generation, and on the other hand, the excess power generation of the generator is stored in the lithium battery through the inverter. Deep peak shaving can be achieved.

[0025] The electric energy stored in the lithium battery can be directly transmitted to the power grid through the inverter, which can ensure the maximum economic benefits of new energy and thermal power unit power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of the present invention.

[0027] Among them, 1 is a power generation device, 2 is a first inverter, 3 is a first control switch, 4 is a wind power generation device, 5 is a second inverter, 6 is a second control switch, 7 is a lithium battery, 8 is a third inverter, 9 is a third control switch, 10 is an electrode heating device, 11 is a power station boiler, 12 is a high-pressure turbine, 13 is a low-pressure turbine, 14 is a generator, 15 is a condenser, 16 is a circulating pump, 17 is a low-temperature heater, 18 is a high-temperature heater, 19 is a fourth inverter, 20 is a fourth control switch, 21 is a power grid, 22 is a first gate valve, 23 is a second gate valve, 24 is a third gate valve, 25 is a fourth gate valve, 26 is a fifth gate valve, and 27 is a sixth gate valve. Specific implementation mode

[0028] The present invention will be further described below with reference to the accompanying drawings:

[0029] Please refer to Figure 1 , a new energy coupled thermal power unit power generation energy storage peak shaving combined system, including a solar power generation device 1, a first inverter 2, a first control switch 3, a wind power generation device 4, a second inverter 5, a second control switch 6, a lithium battery 7, a third inverter 8, a third control switch 9, and an electrode heating device 10.

[0030] A power station boiler 11, a high-pressure turbine 12, a low-pressure turbine 13, a generator 14, a condenser 15, a circulating pump 16, a low-temperature heater 17, a high-temperature heater 18, a fourth inverter 19, a fourth control switch 20, and a power grid 21.

[0031] The system is equipped with a number of first gate valves 22, second gate valves 23, third gate valves 24, fourth gate valves 25, fifth gate valves 26, and sixth gate valves 27.

[0032] The solar power generation device 1 is divided into two paths. One path is connected to the lithium battery 7, and a first inverter 2 and a first control switch 3 are arranged therebetween; the other path is connected to the power grid 21.

[0033] The wind power generation device 4 is divided into two paths. One path is connected to the lithium battery 7, and a second inverter 5 and a second control switch 6 are arranged therebetween; the other path is connected to the power grid 21.

[0034] The thermal power unit system is arranged such that the outlet of the boiler 11 is connected to the high-pressure turbine 12 and the low-pressure turbine 13 in sequence; the outlet of the low-pressure turbine 13 is connected to the condenser 15; the outlet of the condenser 15 is connected to the circulating pump 16, the low-temperature heater 17, and the high-temperature heater 18 in sequence. The generator 14 is connected to the high-pressure turbine 12 and the low-pressure turbine 13. The generator 14 is divided into two paths. One path is connected to the power grid 21; the other path is connected to the lithium battery 7, and a fourth inverter 19 and a fourth control switch 20 are arranged therebetween.

[0035] The lithium battery 7 is connected to the power grid 21, and a third inverter 8 is arranged in the middle.

[0036] The solar power generation device 1 is divided into two paths. One path is connected to the lithium battery 7, and a first inverter 2 and a first control switch 3 are arranged therebetween; the other path is connected to the power grid 21.

[0037] The wind power generation device 4 is divided into two paths. One path is connected to the lithium battery 7, and a second inverter 5 and a second control switch 6 are arranged therebetween; the other path is connected to the power grid 21.

[0038] An electrode heating device 10 is arranged in the system.

[0039] The lithium battery 7 is connected to the electrode heating device 10, and a third control switch 9 is arranged therebetween.

[0040] The electrode heating device 10 is in parallel with the low-temperature heater 17 and the high-temperature heater 18, and two gate valves are arranged in each of the two circuits.

[0041] The generator 14 is divided into two paths. One path is connected to the power grid 21; the other path is connected to the lithium battery 7, and a fourth inverter 19 and a fourth control switch 20 are arranged therebetween.

[0042] The lithium battery 7 is respectively connected to the electrode heating device 10, the solar power generation device 1, the wind power generation device 4, the generator 14, and the power grid 21.

[0043] An operation method for a new energy coupled thermal power unit power generation energy storage peak shaving combined system includes the following steps:

[0044] When the wind power generation 1 or the solar power generation 4 is sufficient and stable, Plan 1: All the power generation capacities are directly sent into the power grid 21 for users to use. Plan 2: Part of the electric quantity is input into the lithium battery 7 through the inverter 2 and the inverter 5 for energy storage.

[0045] When the wind power generation 1 or the solar power generation 4 is intermittent and unstable, the power generation amount in this period is also input into the lithium battery 7 through the inverter 2 and the inverter 5 for energy storage. On the one hand, it avoids the impact on the power grid, and on the other hand, it makes full use of clean energy.

[0046] When the power generation capacity demand of the thermal power unit is large, the heat source of the regenerative system is taken from the electrode heater. The specific operation is as follows: Close the first gate valve 22, the second gate valve 23, the third gate valve 24, and the fourth gate valve 25, open the fifth gate valve 26 and the sixth gate valve 27, and at the same time start the control switch 9 and the control switch 20 to ensure the smoothness of the discharge circuit and the boiler bypass feed water system. Utilize the electric quantity stored in the lithium battery 7 to heat the boiler return water through the electrode heating device 10, heat the boiler feed water to 250 °C, and improve the working medium temperature of the boiler return water system. Instead of the steam extraction of the steam turbine, the power generation amount is increased and the coal consumption is reduced.

[0047] When the power generation capacity demand of the thermal power unit is low and deep peak shaving is required, open the first gate valve 22, the second gate valve 23, the third gate valve 24, and the fourth gate valve 25, close the fifth gate valve 26 and the sixth gate valve 27, start the steam extraction heating system of the boiler for the return water, cut off the electrode heating system, and at the same time turn on the energy storage control switch 20 of the thermal power unit. On the one hand, reduce the power generation of the steam turbine and the power generation, and on the other hand, the excess power generation of the generator is stored in the lithium battery 7 through the inverter 19. Deep peak shaving can be achieved.

[0048] The electric energy stored in the lithium battery 7 can be directly transmitted to the power grid through the inverter 8, which can ensure the maximum economic benefits of the new energy and the power generation of the thermal power unit.

Claims

1. Operating method of a power generation and energy storage peak shaving combined system for a new energy-coupled thermal power unit, characterized in that, Based on the new energy-coupled thermal power unit power generation and energy storage peak shaving combined system, it includes a solar power generation device (1), a wind power generation device (4), a lithium battery (7), a power station boiler (11), a high-pressure turbine (12), a low-pressure turbine (13), a generator (14), a low-temperature heater (17), a high-temperature heater (18) and a power grid (21); the solar power generation device (1) is divided into two paths, one path is connected to the lithium battery (7), and the other path is connected to the power grid (21); the wind power generation device (4) is divided into two paths, one path is connected to the lithium battery (7), and the other path is connected to the power grid (21); the outlet of the power station boiler (11) is sequentially connected to the high-pressure turbine (12) and the low-pressure turbine (13), and the outlet of the low-pressure turbine (13) is sequentially connected to the low-temperature heater (17) and the high-temperature heater (18); the generator (14) is connected to the low-pressure turbine (13); the output end of the generator (14) is divided into two paths, one path is connected to the power grid (21), and the other path is connected to the lithium battery (7); An electrode heating device (10) is connected in parallel on the circuits of the low-temperature heater (17) and the high-temperature heater (18). A fifth gate valve (26) is arranged between the electrode heating device (10) and the low-temperature heater (17), and a sixth gate valve (27) is arranged between the electrode heating device (10) and the high-temperature heater (18); The high-pressure turbine (12) is connected to the high-temperature heater (18), and the low-pressure turbine (13) is connected to the low-temperature heater (17); a first gate valve (22) is arranged at the inlet of the low-temperature heater (17), a second gate valve (23) is arranged at the outlet of the high-temperature heater (18), a fourth gate valve (25) is arranged between the high-pressure turbine (12) and the high-temperature heater (18), and a third gate valve (24) is arranged between the low-pressure turbine (13) and the low-temperature heater (17); the lithium battery (7) is connected to the electrode heating device (10), and a third control switch (9) is arranged in the middle; a fourth inverter (19) and a fourth control switch (20) are arranged between the generator (14) and the lithium battery (7); the lithium battery (7) is connected to the power grid (21), and a third inverter (8) is arranged in the middle; It includes the following steps: When the wind power generation device or the solar power generation device is sufficient and stable, Plan 1: All the generated capacity is directly sent into the power grid (21) for users to use; Plan 2: Part of the electric energy is input into the lithium battery (7) through the first inverter (2) and the second inverter (5) for energy storage; When the wind power generation device or the solar power generation device is intermittent and unstable, the generated electricity in this period is also input into the lithium battery (7) through the first inverter (2) and the second inverter (5) for energy storage. On the one hand, it avoids the impact on the power grid, and on the other hand, it makes full use of clean energy; When the power generation capacity demand of the thermal power unit is large, the heat source of the regenerative system is taken from the electrode heating device, and the specific operation is as follows: Close the first gate valve (22), the second gate valve (23), the third gate valve (24), the fourth gate valve (25), open the fifth gate valve (26) and the sixth gate valve (27), and at the same time start the third control switch (9) and the fourth control switch (20) to ensure the smoothness of the discharge circuit and the boiler bypass feed water system; Utilize the electric quantity stored in the lithium battery (7) to heat the boiler return water through the electrode heating device (10), heat the boiler feed water to 250 °C, and increase the working medium temperature of the boiler return water system; Replace the steam extraction of the steam turbine, increase the power generation, and reduce the coal consumption; When the power generation capacity demand of the thermal power unit is low and deep peak shaving is required, open the first gate valve (22), the second gate valve (23), the third gate valve (24), the fourth gate valve (25), close the fifth gate valve (26) and the sixth gate valve (27), start the steam extraction of the steam turbine to heat the boiler return water system, cut off the electrode heating system, and at the same time open the fourth control switch (20) of the energy storage of the thermal power unit; On the one hand, reduce the power generation of the steam turbine and the power generation, and on the other hand, the excess power generation of the generator is stored in the lithium battery (7) through the fourth inverter (19); The electric quantity stored in the lithium battery (7) is directly transmitted to the power grid through the third inverter (8).

2. The new energy-coupled thermal power unit power generation energy storage peak shaving combined system according to claim 1, wherein A first inverter (2) and a first control switch (3) are arranged between the solar power generation device (1) and the lithium battery (7).

3. The new energy-coupled thermal power unit power generation energy storage and peak shaving combined system according to claim 1, characterized in that A second inverter (5) and a second control switch (6) are arranged between the wind power generation device (asd4) and the lithium battery (7).

4. The new energy-coupled thermal power unit power generation, energy storage and peak shaving combined system according to claim 1, wherein, A condenser (15) and a circulation pump (16) are connected in sequence between the outlet of the low-pressure turbine (13) and the low-temperature heater (17).

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