阅读说明：本技术 一种深度调峰发电系统 (Deep peak regulation power generation system ) 是由 王喜华 陈台杰 纪凯 莫一波 于 2020-12-11 设计创作，主要内容包括：本发明公开了一种深度调峰火力发电系统,该系统包括：锅炉,汽轮机组,熔盐储放能系统,冷凝给水系统,旁路系统辅助系统,所述锅炉包括,锅炉过热器和锅炉再热器,所述汽轮机组包括相互连接的汽轮机高压缸、汽轮机中压缸和汽轮机低压缸,还包括连通管,所述熔盐储放能系统包括主蒸汽/熔盐换热器,再热蒸汽/熔盐换热器,热熔盐罐,冷熔盐罐,熔盐蒸汽加热器,所述冷凝给水系统包括冷凝器,给水泵,所述旁路辅助系统包含高压蒸汽旁路,中压蒸汽旁路以及低压排汽旁路。本发明汽机响应负荷速率快,并且节省了投资,提高了设备安全性,调峰能力大幅增加。(The invention discloses a deep peak regulation thermal power generation system, which comprises: the boiler, the turbine unit, fused salt storage and release can the system, the condensation water supply system, bypass system auxiliary system, the boiler includes, boiler superheater and boiler reheater, the turbine unit includes interconnect's steam turbine high pressure jar, steam turbine intermediate pressure jar and steam turbine low pressure jar, still includes communicating pipe, fused salt storage and release can the system includes main steam/fused salt heat exchanger, reheat steam/fused salt heat exchanger, hot melt salt jar, cold melt salt jar, fused salt steam heater, the condensation water supply system includes the condenser, and the feed pump, bypass auxiliary system contains high-pressure steam bypass, medium-pressure steam bypass and low pressure steam exhaust bypass. The steam turbine has high load response speed, saves investment, improves the equipment safety and greatly increases the peak regulation capacity.)

1. The deep peak shaving thermal power generation system is characterized by comprising a boiler, a steam turbine set, a fused salt storage and release energy system, a condensation water supply system and a bypass system auxiliary system, wherein the boiler comprises a boiler superheater and a boiler reheater, the steam turbine set comprises a steam turbine high-pressure cylinder, a steam turbine medium-pressure cylinder and a steam turbine low-pressure cylinder which are connected with each other, the fused salt storage and release energy system further comprises a communicating pipe, the fused salt storage and release energy system comprises a main steam/fused salt heat exchanger, a reheated steam/fused salt heat exchanger, a hot-melting salt tank, a cold-melting salt tank and a fused salt steam heater, the condensation water supply system comprises a condenser and a water supply pump, and the bypass auxiliary system comprises a high-pressure steam bypass, a medium-pressure steam; the steam side inlet of the main steam/molten salt heat exchanger is connected with the boiler superheater and the steam turbine high-pressure cylinder through a high-pressure steam bypass pipeline, the steam side outlet of the main steam/molten salt heat exchanger is connected with the exhaust steam of the steam turbine high-pressure cylinder and a boiler reheater, the steam side inlet of the reheater steam/molten salt heat exchanger is connected with the boiler reheater through a pipeline, the steam outlet of the reheater steam/molten salt heat exchanger is connected with the communicating pipe, the inlet of the steam turbine intermediate-pressure cylinder is connected with the outlet of the boiler reheater and the steam side inlet of the reheater steam/molten salt heat exchanger, the inlet of the steam turbine low-pressure cylinder is connected with the communicating pipe and connected with the condenser through a pipeline, and the exhaust steam of the steam turbine intermediate-pressure cylinder is connected with the condenser through, the condenser is connected with a water inlet of the molten salt steam heater through the water feed pump, an outlet of the condenser is connected with a steam side inlet of the molten salt/steam heater through a pipeline, a water outlet of the molten salt steam heater is connected with the low-pressure cylinder of the steam turbine, a molten salt side inlet of the molten salt steam heater is connected with the hot-melt salt tank through a pipeline, an outlet of the molten salt steam heater is connected with the cold-melt salt tank through a pipeline, a molten salt side inlet of the main steam/molten salt heat exchanger is connected with the cold-melt salt tank through a molten salt pipeline, a molten salt side outlet of the molten salt heat exchanger is connected with the hot-melt salt tank through a molten salt pipeline, a molten salt side inlet of the reheated steam/molten salt heat exchanger is connected with the cold-melt salt; boiler over heater is used for producing steam, and steam gets into through the pipeline main steam/fused salt heat exchanger steam side entry with the steam turbine high pressure cylinder, a small amount of steam turbine intermediate pressure cylinder steam extraction passes through intermediate pressure steam extraction bypass system with the condenser links to each other, prevents middling pressure final stage blast and overtemperature, reheat steam/fused salt heat exchanger utilizes its sensible heat to adjust the entering the temperature of steam turbine low pressure cylinder steam reduces steam turbine low pressure cylinder steam extraction enthalpy value, the thermohalite in the thermohalite jar passes through the entering fused salt/steam heater heating feedwater, passes through behind the feedwater evaporation for steam communicating pipe mends the work of steam turbine low pressure cylinder, the unnecessary heat of boiler is all stored and is used when treating the electric wire netting in the fused salt energy storage system and lifting load.

2. The system of claim 1, wherein the intermediate pressure steam exhaust bypass system is connected to the condenser via a check valve and an intermediate exhaust vent valve.

3. The system of claim 1, wherein the low pressure turbine cylinders each have a double split flow configuration and the inlet steam temperature of the low pressure turbine cylinders is within 400 ℃.

4. The system of claim 1, wherein the reheat steam/molten salt heat exchanger is configured to increase the turbine low pressure cylinder exhaust flow without condensing the passing steam.

5. The system of claim 1, wherein the reheat steam/molten salt heat exchanger steam side inlet, the main steam/molten salt heat exchanger steam inlet, and the molten salt steam heater water side inlet are provided with a throttle valve.

Technical Field

The invention relates to the technical field of fused salt energy storage, in particular to a deep peak shaving power generation system.

Background

Due to the rapid development of new energy power generation and the surplus of coal electricity production capacity in China, the flexible transformation of coal electricity is imperative. When the proportion of new energy in the power grid is gradually enlarged, the demand on the peak shaving power supply is gradually increased; meanwhile, the increasingly expanded peak-valley power utilization difference is combined with the reduction of the whole load requirement of the thermal power generating unit, so that the load of the unit is further reduced to be lower than the lowest stable combustion load of the thermal power generating unit in the valley power time period. The changes can cause the safety reliability and the economical efficiency of the produced thermal power generating units to be greatly reduced, and the aim of sustainable development of energy revolution is not met. Therefore, the development of new deep peak shaving systems and techniques is urgent.

The deep peak regulation is an operation mode that the load of each power plant is reduced due to the larger influence of the load peak-valley difference of the power grid, and the peak regulation is carried out when the turbo generator unit exceeds the basic peak regulation range; the load range of deep peak shaving exceeds the lowest stable combustion load of the power plant boiler and the minimum long-term continuous operation load of the steam turbine generator unit. As shown in fig. 1 and 2, for a thermal power plant, the main factors affecting the depth peak shaving are as follows:

1. and (3) stable combustion of the boiler: when the combustion condition of the boiler is far lower than the designed minimum stable operation load (generally 40% load), the temperature of the hearth can be rapidly reduced, so that the pulverized coal is difficult to quickly catch fire, and further serious potential safety hazards such as flame failure, hearth fire extinguishment and the like are easily caused.

2. Final stage blast or overtemperature of the steam turbine: in the deep peak regulation process, due to the fact that the volume flow is reduced, the last stage of the low-pressure cylinder of the steam turbine and most part of the next last stage are in a blast state, the low-pressure last stage blade is easy to overheat, and the last stage blade of the low-pressure cylinder of the steam turbine is broken in serious cases, so that the low-pressure cylinder of the steam turbine is guaranteed to work above the minimum volume flow (generally, the design value is above 30%).

The fused salt energy storage power supply and heat supply technology is successfully applied to solar thermal power generation stations and has the advantages of mature technology and relatively low cost. The method is applied to thermal power generating units to participate in peak regulation power supply and heat supply, and is technically and economically feasible. Therefore, under the background that the whole-grid thermal power generating unit participates in peak shaving, in order to solve the problems that the thermal power generating unit deeply performs peak shaving to the lowest stable load and the steam turbine operates under the minimum flow working condition, a more efficient fused salt energy storage peak shaving power supply and heat supply system coupled with the thermal power generating unit is urgently needed to be developed.

Disclosure of Invention

The invention aims to provide a deep peak-shaving power generation system for realizing zero output of a high and medium pressure cylinder of a steam turbine, and aims to solve the problem of deep peak-shaving operation of the steam turbine below 30% of load.

The embodiment of the invention provides a deep peak shaving thermal power generation system, which comprises a boiler, a steam turbine set, a fused salt storage and release energy system, a condensation water supply system and a bypass system auxiliary system, wherein the boiler comprises a boiler superheater and a boiler reheater, the steam turbine set comprises a steam turbine high-pressure cylinder, a steam turbine medium-pressure cylinder and a steam turbine low-pressure cylinder which are mutually connected, the fused salt storage and release energy system also comprises a communicating pipe, the fused salt storage and release energy system comprises a main steam/fused salt heat exchanger, a reheated steam/fused salt heat exchanger, a hot-melted salt tank, a cold-melted salt tank and a fused salt steam heater, the condensation water supply system comprises a condenser and a water supply pump, and the bypass auxiliary system comprises a high-pressure steam; the steam side inlet of the main steam/molten salt heat exchanger is connected with a boiler superheater and a steam turbine high-pressure cylinder through a high-pressure steam bypass pipeline, the steam side outlet of the main steam/molten salt heat exchanger is connected with the exhaust steam of a steam turbine high-pressure cylinder and a boiler reheater, the steam side inlet of the reheater steam/molten salt heat exchanger is connected with the boiler reheater through a pipeline, the steam outlet of the reheater steam/molten salt heat exchanger is connected with a communicating pipe, the inlet of a steam turbine medium-pressure cylinder is connected with the outlet of the boiler reheater and the steam side inlet of the reheater steam/molten salt heat exchanger, the inlet of the steam turbine low-pressure cylinder is connected with the communicating pipe and connected with a condenser through a pipeline, the exhaust steam of the steam turbine medium-pressure steam exhaust bypass system is connected with the condenser, the condenser is connected with the, a water outlet of the fused salt steam heater is connected with a low-pressure cylinder of a steam turbine, a fused salt side inlet of the fused salt steam heater is connected with a hot-melt salt tank through a pipeline, an outlet of the fused salt steam heater is connected with a cold-melt salt tank through a pipeline, a fused salt side inlet of the main steam/fused salt heat exchanger is connected with the cold-melt salt tank through a fused salt pipeline, a fused salt side outlet of the main steam/fused salt heat exchanger is connected with the hot-melt salt tank through a fused salt pipeline, a fused salt side inlet of the reheat steam/fused salt heat exchanger is connected with the cold-melt salt tank through a; the boiler superheater is used for generating steam, the steam enters a steam side inlet of the main steam/molten salt heat exchanger and a high-pressure steam turbine cylinder through a pipeline, a small amount of steam exhausted by the medium-pressure steam exhaust bypass system of the medium-pressure steam/molten salt heat exchanger is connected with a condenser to prevent medium-pressure last-stage blowing and overtemperature, the reheated steam/molten salt heat exchanger utilizes sensible heat thereof to adjust the temperature of the steam entering the low-pressure steam turbine cylinder, the exhaust enthalpy value of the low-pressure steam turbine cylinder is reduced, hot salt in the hot-melt salt tank enters the molten salt/steam heater to heat water supply, the water supply is evaporated into the steam and then is supplemented into the low-pressure steam turbine cylinder through a communicating pipe to do work, and redundant heat of.

The medium-pressure steam exhaust bypass system is connected with the condenser through a check valve and a medium-pressure exhaust ventilation valve.

The low-pressure cylinder of the steam turbine adopts a double-split structure, and the steam inlet temperature of the low-pressure cylinder of the steam turbine is within 400 ℃.

And the reheat steam/molten salt heat exchanger is used for preventing the passing steam from condensing and increasing the exhaust flow of the low-pressure cylinder of the steam turbine.

Throttle valves are arranged at the steam side inlet of the reheat steam/molten salt heat exchanger, the steam inlet of the main steam/molten salt heat exchanger and the water side inlet of the molten salt steam heater.

The embodiment of the invention realizes load decoupling of the boiler and the steam turbine, when the thermal power generating unit runs at low or extremely low load caused by deep peak load regulation or peak-valley difference of a power grid, the boiler still runs according to the lowest stable combustion load, the response load rate of the steam turbine is high, the investment is saved, and the safety of equipment is improved.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic diagram of a last stage flow line of a turbine in a deep peaking thermal power generation system according to the prior art under normal operating conditions;

FIG. 2 is a schematic diagram of the last stage flow line during low load operation of the steam turbine of a deep peaking thermal power generation system of the prior art;

FIG. 3 is a schematic diagram of a deep peak shaver thermal power generation system in accordance with an embodiment of the present invention;

fig. 4 is a schematic diagram of a conventional system thermal power generation.

Description of reference numerals:

the system comprises a boiler 1, a boiler superheater 1-1, a boiler reheater 1-2, a turbine high-pressure cylinder 2, a turbine intermediate-pressure cylinder 3, a turbine low-pressure cylinder 4, a throttle valve I5, a fused salt heating heat exchanger 6-1, a fused salt/steam heater 7, a throttle valve II 8, a reheated steam/fused salt heat exchanger 7, a check valve 9, a middle exhaust ventilation valve 10, a condenser 11, a water feed pump 12, a hot-melt salt tank 13, a cold-melt salt tank 14, a throttle valve III 15 and a communicating pipe 16.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Furthermore, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Device embodiment

According to an embodiment of the present invention, a deep peak shaving power generation system is provided, fig. 3 is a schematic system diagram of an embodiment of the present invention, and as shown in fig. 3, the deep peak shaving power generation system specifically includes: the system comprises a boiler 1, a steam turbine set, a molten salt storage and release energy system, a condensation water supply system and a bypass system auxiliary system, wherein the boiler 1 comprises a boiler superheater 1-1 and a boiler reheater 1-2, the steam turbine set comprises a steam turbine high-pressure cylinder 2, a steam turbine intermediate-pressure cylinder 3 and a steam turbine low-pressure cylinder 4 which are connected with one another, and further comprises a communicating pipe 16, the molten salt storage and release energy system comprises a main steam/molten salt heat exchanger 6-1, a reheated steam/molten salt heat exchanger 6-2, a hot molten salt tank 13, a cold molten salt tank 14 and a molten salt steam heater 7, the condensation water supply system comprises a condenser 11 and a water supply pump 12, and the bypass auxiliary system comprises a high-pressure steam bypass, an intermediate-; a steam side inlet of a main steam/molten salt heat exchanger 6-1 is connected with a boiler superheater 1-1 and a steam turbine high-pressure cylinder 2 through a high-pressure steam bypass pipeline, a steam side outlet of the main steam/molten salt heat exchanger 6-1 is connected with exhaust steam of the steam turbine high-pressure cylinder 2 and a boiler reheater 1-2, a steam side inlet of the reheated steam/molten salt heat exchanger 6-2 is connected with the boiler reheater 1-1 through a pipeline, a steam outlet of the reheated steam/molten salt heat exchanger 6-2 is connected with a communicating pipe 16, an inlet of a steam turbine intermediate pressure cylinder 3 is connected with a steam side inlet of the boiler reheated steam/molten salt heat exchanger 6-2, an inlet of a steam turbine low-pressure cylinder 4 is connected with the communicating pipe 16 and is connected with a condenser 11 through a pipeline, and steam is condensed in the condenser 11 and then enters a steam drum of the boiler. The water side inlet of a fused salt steam heater 7 is connected with a steam pocket or a deaerator through a pipeline, the exhaust steam of a steam turbine intermediate pressure cylinder 3 is connected with a condenser 11 through a steam turbine intermediate pressure exhaust steam bypass system, the condenser 11 is connected with the water inlet of the fused salt steam heater 7 through a water feed pump 12, the outlet of the condenser 11 is connected with the steam side inlet of the fused salt/steam heater through a pipeline, the water outlet of the fused salt steam heater 7 is connected with a steam turbine low pressure cylinder 4, the fused salt side inlet of the fused salt steam heater 7 is connected with a hot molten salt tank 13 through a pipeline, the outlet is connected with a cold molten salt tank 14 through a pipeline, the fused salt side inlet of a main steam/fused salt heat exchanger 6-1 is connected with the cold molten salt tank 14 through a fused salt pipeline, the fused salt side outlet is connected with the hot molten salt tank 13 through a fused salt pipeline, and the fused salt side inlet, the fused salt side outlet is connected with a fused salt tank 13 through a fused salt pipeline; the boiler superheater 1-1 is used for generating steam, the steam enters a steam side inlet of a main steam/molten salt heat exchanger 6-1 and a steam turbine high-pressure cylinder 2 through a pipeline, a small amount of steam exhausted by a steam turbine intermediate-pressure cylinder 3 is connected with a condenser 11 through a medium-pressure steam exhaust bypass system to prevent medium-pressure final-stage blast and overtemperature, the reheated steam/molten salt heat exchanger 6-2 utilizes sensible heat thereof to adjust the temperature of the steam entering a steam turbine low-pressure cylinder 4, the steam exhaust enthalpy value of the steam turbine low-pressure cylinder 4 is reduced, hot salt in a hot-melt salt tank enters a molten salt/steam heater to heat feed water, the feed water is evaporated into the steam and then is supplemented into the steam turbine low-pressure cylinder 4 through a communicating pipe 16 to do work, and all redundant heat of. The medium-pressure steam exhaust bypass system is connected with a condenser 11 through a check valve 9 and a medium-pressure vent valve 10. The steam turbine low pressure cylinder 4 adopts a double-split structure, and the steam inlet temperature of the steam turbine low pressure cylinder 4 is within 400 ℃. And the reheat steam/molten salt heat exchanger 6-2 is used for preventing the passing steam from condensing and increasing the exhaust steam flow of the low-pressure cylinder 4 of the steam turbine. A steam side inlet of the reheat steam/molten salt heat exchanger 6-2, a steam inlet of the main steam/molten salt heat exchanger 6-1 and a water side inlet of the molten salt steam heater 7 are provided with a throttle valve 8, a throttle valve 5 and a throttle valve 15.

In the embodiment of the invention, when the load demand of a power grid on a unit is lower than the minimum stable combustion load of a boiler or the load of the final-stage minimum volume flow working condition of a steam turbine, the energy storage mode is started.

The method comprises the following steps that a boiler 1 keeps the lowest stable combustion load, such as 40% load, the minimum volume flow of the last stage of a steam turbine is 40% of a design working condition, most main steam at an outlet of a boiler superheater 1-1 enters a main steam/molten salt heat exchanger 6-1 through a high-pressure steam bypass system, a small amount of steam enters a steam turbine high-pressure cylinder 2 to maintain the minimum cooling flow of the steam turbine high-pressure cylinder 2, the steam turbine high-pressure cylinder 2 is in a zero-output state, exhaust steam of the steam turbine high-pressure cylinder and steam at an outlet of the main steam/molten salt heat exchanger 6-1 are mixed and then enter a reheater 1-2, and the lowest stable combustion load; most steam at the outlet of the boiler reheater enters the reheated steam/molten salt heat exchanger 6-2 through the low-pressure steam bypass system, a small amount of steam enters the steam turbine intermediate pressure cylinder 3 to maintain the minimum cooling flow of the steam turbine intermediate pressure cylinder 3, the steam turbine intermediate pressure cylinder 3 is in a zero-output state, and a small amount of intermediate-pressure steam-exhausted steam is connected with the condenser 11 through the increased intermediate-pressure steam-exhausted bypass system through the check valve 9 and the intermediate-pressure vent valve 10 to prevent intermediate-pressure final-stage air blast and overtemperature. The reheated steam passes through the reheated steam/molten salt heat exchanger 6-2, the temperature is greatly reduced but is not condensed, the outlet steam enters the steam turbine low pressure cylinder 4 through a communicating pipe, the minimum volume flow of the steam turbine low pressure cylinder 4 is maintained unchanged, the exhaust steam flow of the steam turbine low pressure cylinder 4 is increased, the minimum flow of the steam turbine high pressure cylinder 2 and the steam turbine intermediate pressure cylinder 3 is not limited by the final stage minimum flow of the steam turbine low pressure cylinder 4 any more, the steam turbine high pressure cylinder 2 and the steam turbine intermediate pressure cylinder 3 can achieve zero output to achieve deep peak regulation of the thermal power generation steam turbine, meanwhile, the reheated steam/molten salt heat exchanger 6-2 can adjust the temperature of the steam entering the steam turbine low pressure cylinder 4 only by utilizing the sensible heat thereof, the exhaust steam enthalpy value of the steam turbine. In order to prevent the exhaust steam of the steam turbine intermediate pressure cylinder 3 from being over-temperature, an intermediate pressure exhaust steam bypass system is additionally arranged and is connected with a condenser 11 through a check valve 9 and an intermediate exhaust ventilation valve 10, and the exhaust steam pressure of the steam turbine intermediate pressure cylinder 3 is reduced.

When the power grid requires the unit to rapidly load up, the hot salt stored in the hot-melt salt tank 13 enters the molten salt/steam heater 7 to heat the feed water, the feed water is evaporated into steam and then is supplemented into the low-pressure turbine cylinder 4 through the communicating pipe 16 to do work, the output of the turbine is rapidly increased, meanwhile, the low-pressure turbine cylinder 4 of the thermal power generation adopts a double-shunt structure, and the steam inlet temperature of the low-pressure turbine cylinder 4 is generally within 400 ℃.

The embodiment of the invention realizes load decoupling of a boiler 1 and a steam turbine, when a thermal power generating unit runs at low or extremely low load due to deep peak load regulation or peak-valley difference of a power grid, the boiler 1 still runs according to the lowest stable combustion load, most steam at the outlet of a boiler superheater 1-1 enters a main steam/molten salt heat exchanger 6-1 through a high-pressure steam bypass system, a small amount of steam enters a steam turbine high-pressure cylinder 2 to maintain the minimum cooling flow of the steam turbine high-pressure cylinder 2, the steam turbine high-pressure cylinder 2 is in a zero-output state, the exhaust steam of the steam turbine high-pressure cylinder 2 and the steam at the outlet of the main steam/molten salt heat exchanger 6-1 are mixed and then enter a boiler reheater 1-2 to maintain the lowest stable; most steam at the outlet of the boiler reheater 1-2 enters the reheated steam/molten salt heat exchanger 6-2 through the low-pressure steam bypass system, a small amount of steam enters the steam turbine intermediate pressure cylinder 3 to maintain the minimum cooling flow of the steam turbine intermediate pressure cylinder 3, the steam turbine intermediate pressure cylinder 3 is in a zero-output state, and a small amount of intermediate-pressure steam exhaust steam is connected with the condenser 11 through the added intermediate-pressure steam exhaust bypass system to prevent intermediate-pressure final-stage air blast and overtemperature. The reheated steam is greatly reduced in temperature but not condensed after passing through the reheated steam/molten salt heat exchanger 6-2, the outlet steam of the reheated steam enters the low-pressure turbine cylinder through the communicating pipe 16, the minimum volume flow of the low-pressure turbine cylinder 4 is maintained, blowing loss of the last stage of the turbine is prevented, the turbine only applies work to the low-pressure turbine cylinder 4, the peak regulation capacity is greatly increased, and meanwhile equipment safety is guaranteed.

The steam is not condensed after passing through the reheat steam/molten salt heat exchanger 6-1, the temperature of the steam entering the low-pressure cylinder 2 of the steam turbine can be adjusted only by utilizing the sensible heat of the steam, the temperature of the steam entering the low-pressure cylinder 2 of the steam turbine is prevented from being over-heated when the partial load reheat pressure is too low, the last-stage blade is prevented from being in an overheat state, and meanwhile, the heat loss of exhaust steam is reduced.

When the power grid is in load increase, the hot salt stored in the hot-melt salt tank 13 enters the molten salt/steam heater 7 to heat the feed water, the feed water is evaporated into steam and then is supplemented into the low-pressure steam turbine cylinder 4 through the communicating pipe 16 to do work, the output of the steam turbine is increased rapidly, meanwhile, the low-pressure steam turbine cylinder 4 of the thermal power generation adopts a double-shunt structure, the steam inlet temperature of the low-pressure steam turbine cylinder 2 is generally within 400 ℃, the quick load increase through the steam supplementation of the low-pressure steam turbine cylinder 2 cannot affect the service life of equipment, the response load rate of the steam turbine is high, the investment is saved, and the safety of the equipment is.

Compared with the traditional thermal power generation system (figure 4), the invention has the advantages of high response load rate, investment saving, equipment safety improvement and great increase of peak regulation capacity.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.