CN112814860A - Circulating complementary cogeneration system of tower type solar photo-thermal power generation refrigerator and operation method thereof - Google Patents

Abstract

A circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator and an operation method thereof belong to the field of mechanical engineering and energy conservation. The problem of among the prior art power island circulation back pressure higher under summer operating mode to and the unable high-efficient operation of operating mode of cogeneration system can't be solved. The key points are as follows: the system comprises a tower type solar heat collection system, a power island system and a heat pump refrigeration cycle waste heat recovery system; the cold end low-grade waste heat of the power island system circulation and the heat pump refrigeration circulation waste heat recovery system utilize the same heat exchanger or a group of heat exchangers, combination of two subsystems is achieved, refrigeration capacity of heat pump circulation evaporation is utilized to cool circulating water, cold end waste heat of the power island system is converted into effective heat supply output, and the system can be used for user heat supply and can also achieve water supply preheating. On the premise of low cost, the invention realizes comprehensive cascade utilization of energy, high-efficiency operation of the steam turbine island all the year round, and simultaneously completes considerable heat supply demand in winter, thereby improving the utilization efficiency of the energy.

Description

Circulating complementary cogeneration system of tower type solar photo-thermal power generation refrigerator and operation method thereof

Technical Field

The invention relates to a solar energy cogeneration system and an operation method thereof, in particular to a circulating complementary cogeneration system of a tower type solar photo-thermal power generation refrigerator and an operation method thereof, belonging to the technical field of mechanical engineering and energy conservation.

Background

Energy shortage and environmental problems have become major bottlenecks restricting global economic and social development, and will affect the survival status of human beings in the future. Solar energy is the most abundant and widely available renewable energy form in China and all over the world, and has a particularly important role in solving energy crisis and environmental problems due to its characteristics of cleanness and no pollution. Solar power generation systems have various forms, mainly including photovoltaic and photo-thermal. Photovoltaic is because the energy distribution density who shines is little, will occupy huge area promptly, is unfavorable for constructing large capacity power station, also has the factor of not environmental protection in the photovoltaic board manufacturing process simultaneously, consequently to large capacity unit, and light and heat is main development direction.

At present, the solar thermal power generation is mainly divided into four forms according to the difference of a solar collection system: trough, linear (fresnel), dish, and tower. The trough type solar thermal power generation system utilizes a trough type paraboloid to carry out light condensation power generation, generally adopts heat conduction oil as a heat transfer and storage medium, has low light condensation ratio, heat collection temperature and power generation efficiency, has mature technology, and starts to be commercially operated as early as eighty years of the last century; the tower type solar thermal power generation system utilizes the heliostat to gather solar radiation energy for power generation, has higher light gathering ratio, heat collecting temperature and power generation efficiency, generally adopts molten salt and superheated steam as heat transfer and heat storage media, and has built and operated a plurality of demonstration or commercial power stations worldwide; the disc type solar thermal power generation system performs light-gathering power generation by using the parabolic reflector, has small scale and can be used for a distributed energy system; the linear solar thermal power generation system mainly utilizes a Fresnel mirror to condense and generate power and is in the research and development stage at present.

From the aspect of power generation, at present, a rankine cycle power generation system taking steam as a working medium is mainly adopted by the photothermal unit, but the system has some defects which are difficult to overcome. The photothermal power station is generally built in areas with rich illumination resources, and the areas have the characteristics of seasonal difference and large day-night difference.

From the aspect of heat supply, the increase rate of the demand of China for domestic heat is more rapid. Because of low efficiency and high pollution, the small boiler heating is basically replaced by the large boiler central heating according to the relevant national policies. However, from the second law of thermodynamics, there is still a huge waste of energy to directly produce low-grade heat energy from high-grade chemical energy. In recent years, a heat pump cycle has attracted increasing attention as an efficient and energy-saving heating system. The heat pump circularly utilizes low-grade heat energy, improves the comprehensive energy utilization efficiency and has huge energy-saving potential.

Disclosure of Invention

The invention aims to solve the problems that the power island cycle has high backpressure under the working condition of summer and a combined heat and power system cannot run efficiently under the full working condition in the prior art, and further provides a circulating complementary combined heat and power system of a tower type solar photo-thermal power generation refrigerator and an operation method thereof. The invention fully exerts the advantages of combination through the organic combination of a plurality of systems, improves the energy utilization efficiency to more than 80 percent, and has obvious economic benefit, social benefit and engineering application prospect.

In order to achieve the purpose, the invention adopts the following technical scheme:

the first scheme is as follows: a circulating complementary combined heat and power system of a tower-type solar photo-thermal power generation refrigerator comprises a tower-type solar heat collection system, a power island system and a heat pump refrigeration cycle waste heat recovery system;

wherein, the tower-type solar heat collecting system comprises a light condensing tower and a high-temperature heat accumulator which are arranged in a heat accumulating loop in sequence, the low-temperature evaporator provides required driving steam for a heat pump system of a heat pump refrigeration cycle waste heat recovery system, the high-temperature evaporator provides required driving steam for a turbine of a power island system, the turbine does work to generate electricity, the steam exhaust end of the turbine is connected with a condenser, the condenser is respectively in circulating connection with a cooling tower and the heat pump system, a condensed liquid outlet of the condenser is connected with the high-temperature evaporator through a power island water supply loop, the heat pump driving turbine is connected with an inlet end of the condenser, the condensed liquid outlet of the condenser is further connected with the heat pump loop of the heat pump refrigeration cycle waste heat recovery system through a pipeline, and the cold end of the power island system is converted into effective heat supply output for supplying heat to users and realizing water supply preheating.

The working principle is as follows: the cold end low-grade waste heat of the power island system circulation and the heat pump refrigeration circulation waste heat recovery system utilize the same heat exchanger or a group of heat exchangers, the combination of two subsystems is ingeniously realized, the circulating water is cooled by utilizing the refrigerating capacity of the heat pump circulation evaporation, and meanwhile, the cold end waste heat of the power island system is converted into effective heat supply output, so that the system can be used for supplying heat for users and can also realize the preheating of water supply.

Further: the heat pump refrigeration cycle waste heat recovery system comprises a heat pump system outlet, a high-temperature heat storage water tank, a heat user heat exchanger, a low-temperature heat storage water tank and a heat pump system inlet which are sequentially arranged in a heat pump loop.

Further: the power island water supply loop is provided with a booster pump, a three-way control valve III and a three-way control valve II, the booster pump, the three-way control valve III and the three-way control valve II are sequentially arranged between a condenser and a high-temperature evaporator, a three-way control valve IV and a three-way control valve V are arranged in the heat pump loop, the three-way control valve IV is arranged between a heat pump system and a high-temperature water storage tank, the three-way control valve V is arranged between the heat pump system and the low-temperature water storage tank, the three-way control valve III is connected with the three-way control valve V through a pipeline, and the three-way control valve II is connected with.

Further: and a three-way control valve I is arranged in the heat storage loop, and an outlet of the high-temperature evaporator, an inlet of the low-temperature evaporator and an inlet of the low-temperature heat accumulator are connected through the three-way control valve I.

Further: the working medium of the heat pump system adopts organic working medium, water vapor, carbon dioxide or mixed working medium.

Further: the heat pump system adopts an injection type circulation, multi-stage circulation or regenerative circulation arrangement mode.

Scheme II: a method for operating a circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator is realized based on a first scheme. The method specifically comprises the following steps:

the operation process comprises a power island circulation loop, a heat pump heat supply/refrigeration circulation loop and a heat supply loop, and specifically comprises the following steps:

power island circulation loop: the exhaust steam end of the turbine passes through a condenser, and high-pressure water pressurized by a booster pump enters a high-temperature evaporator or a heat pump system to absorb heat and raise the temperature to design parameters;

under the working condition of summer, the exhaust gas of the turbine enters a heat pump system after passing through a condenser, and the heat pump system realizes the recovery of the waste heat of the circulating water and heats the feed water; preheating feed water and then entering a high-temperature evaporator to complete a cycle;

under the working condition in winter, the exhaust gas of the turbine directly enters the high-temperature evaporator after passing through the condenser, then enters the turbine to expand and do work, and the output of the turbine is used for driving the generator to generate electricity to complete a cycle;

heat pump heating/cooling cycle circuit: under the working condition of summer, no heat supply demand exists, and under the condition of high temperature in the daytime, the three-way control valve I controls the heat pump heat supply/refrigeration circulation loop to be put into operation; the three-way control valve III and the three-way control valve V control the condensed water to enter a heat pump system, and the circulating water waste heat is recycled for preheating the condensed water by heat pump circulation; the temperature at night is low, the temperature of the cold end meets the high-efficiency operation requirement of the unit, and the heat pump system is isolated by the control of the three-way control valve I; under the working condition in winter, the heat pump system directly conveys the waste heat recovered from the circulating water to the heat exchanger of the heat user by adjusting the three-way control valve II, the three-way control valve III, the three-way control valve IV and the three-way control valve V, so as to supply heat for the user.

A heat supply loop: the heat pump working medium realizes heating of the heat supply circulating water through the high-temperature heat storage water tank and the low-temperature heat storage water tank, and then the heat supply circulating water supplies heat to users through a heat supply pipe network.

The invention achieves the following effects:

1. the invention comprehensively considers Rankine power cycle and heat pump (refrigeration) cycle, and relates to a combined production system combining tower type solar photo-thermal power generation and heat pump (refrigeration) cycle, wherein the cold end of the Rankine power cycle is combined with the heat pump (refrigeration) cycle, and a tower type solar heat storage system is used as a driving heat source to achieve the purposes of power generation, heat supply and even refrigeration.

2. The invention takes the power island cycle of the tower-type photothermal power generation system as a power subsystem and takes the heat pump (refrigeration) cycle as a combined cycle system of a heat supply (refrigeration) subsystem, wherein the power cycle and the heat pump cycle are connected by one or a group of heat exchangers, and the heat exchangers are used as a cooler of the power cycle and an evaporator of the heat pump (refrigeration) cycle, thereby realizing the organic combination among the subsystems.

3. The invention skillfully realizes the annual high-efficiency operation of the power island system by utilizing the heat pump system, and simultaneously realizes the cascade utilization of energy, thereby reducing the heat emission on one hand and meeting the cold and heat loads of users on the other hand.

4. The invention organically combines a plurality of systems, fully exerts the advantages of the combination, improves the energy utilization efficiency to more than 80%, realizes comprehensive cascade utilization of energy on the premise of lower investment cost, realizes the annual high-efficiency operation of the steam turbine island, completes considerable heat supply demand in winter, can better realize the utilization efficiency of the energy, has novel thought and high feasibility, and has obvious economic benefit, social benefit and engineering application prospect.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention;

in the figure, 1, a light condensing tower; 2. a high temperature heat accumulator; 3. a high temperature evaporator; 4. a low temperature evaporator; 5. a low temperature heat accumulator; 6, a turbine; 7. a condenser; 8. a cooling tower; 9. a heat pump system; 10. a high temperature water storage tank; 11. a low-temperature water storage tank; 12. a heat user heat exchanger; A1. a three-way control valve I; A2. a three-way control valve II; A3. a three-way control valve III; A4. a three-way control valve IV; A5. three-way control valve V.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. 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 application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In this application, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.

Furthermore, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Preferred embodiments of the present invention are explained in detail below with reference to the accompanying drawings.

Example 1: as shown in fig. 1, the circulating complementary cogeneration system of the tower-type solar photo-thermal power generation refrigerator according to the present embodiment includes a tower-type solar heat collection system, a power island system and a heat pump refrigeration cycle waste heat recovery system;

wherein, the tower solar heat collecting system comprises a light condensing tower 1, a high temperature heat accumulator 2, a high temperature evaporator 3, a low temperature evaporator 4 and a low temperature heat accumulator 5 which are arranged in a heat accumulating loop in sequence, the low temperature evaporator 4 provides required driving steam for a heat pump system of the heat pump refrigeration cycle waste heat recovery system, the high temperature evaporator 3 provides required driving steam for a turbine 6 of the power island system, the turbine 6 does work to generate electricity, the dead steam end of the turbine 6 is connected with a condenser 7, the condenser 7 is respectively connected with a cooling tower 8 and the heat pump system in a circulating way, the condensed liquid outlet of the condenser 7 is connected with the high temperature evaporator 3 through a power island water supply loop, the heat pump driving turbine is connected with the inlet end of the condenser, the condensed liquid outlet of the condenser is also connected with the heat pump loop of the heat pump refrigeration cycle waste heat recovery system through a pipeline, and the cold end waste heat of the power, the system is used for supplying heat to users and realizing preheating of water supply; the heat pump refrigeration cycle waste heat recovery system comprises a heat pump system outlet, a high-temperature heat storage water tank 10, a heat user heat exchanger 12, a low-temperature heat storage water tank 11 and a heat pump system inlet which are sequentially arranged in a heat pump loop; a booster pump, a three-way control valve IIIA3 and a three-way control valve IIA2 are arranged on the power island water supply loop, the booster pump, the three-way control valve IIIA3 and the three-way control valve IIA2 are sequentially arranged between the condenser 7 and the high-temperature evaporator 3, a three-way control valve IVA4 and a three-way control valve VA5 are arranged in the heat pump loop, a three-way control valve IVA4 is arranged between the heat pump system 9 and the high-temperature water storage tank 10, a three-way control valve VA5 is arranged between the heat pump system and the low-temperature water storage tank, a three-way control valve IIIA3 is connected with a three-way control valve VA5 through a pipeline, and a three-way control valve IIA2 is connected with; the heat storage loop is provided with a three-way control valve IA1, and the outlet of the high-temperature evaporator, the inlet of the low-temperature evaporator and the inlet of the low-temperature heat accumulator are connected through a three-way control valve IA 1. The working medium of the heat pump system adopts an organic working medium; the heat pump system adopts a jet type circulation arrangement mode.

Example 2: the difference from the embodiment 1 is that the working medium of the heat pump system adopts water vapor; the heat pump system adopts a multi-stage circulation arrangement mode.

Embodiment 3, the difference with embodiment 1 lies in that the working medium of the heat pump system adopts carbon dioxide; the heat pump system adopts a regenerative cycle arrangement mode.

Embodiment 4, the difference with embodiment 1 lies in that the working medium of the heat pump system adopts a mixed working medium; the heat pump system adopts a regenerative cycle arrangement mode.

The working principle of examples 1 to 4 is: the cold end low-grade waste heat of the power island system circulation and the heat pump refrigeration circulation waste heat recovery system utilize the same heat exchanger or a group of heat exchangers, the combination of two subsystems is ingeniously realized, the circulating water is cooled by utilizing the refrigerating capacity of the heat pump circulation evaporation, and meanwhile, the cold end waste heat of the power island system is converted into effective heat supply output, so that the system can be used for supplying heat for users and can also realize the preheating of water supply.

It is emphasized that the solar thermoelectric decoupling system has the following technical characteristics:

(1) the power island circulation working process of the tower type solar power generation system when heat supply is needed is as follows: the pressurized feed water absorbs heat in the heat storage system, the temperature is raised to a given parameter, the feed water enters a turbine to expand and do work, and exhaust gas waste heat is transferred to a working medium at the high-pressure side of the heat pump through a heat exchanger to realize condensation. After condensation, water is pressurized by a pump and finally enters a heat storage system to absorb heat, and a cycle is completed.

(2) When heat supply is not needed, the power island of the tower type solar power generation system circulates in the following working process: after the temperature of the feed water is raised to a given parameter, the feed water enters a turbine to expand and do work, and the waste heat of the exhaust gas is transferred to a working medium at the high-pressure side of the heat pump through a heat exchanger to realize condensation. Meanwhile, after being pressurized by the pump, the condensed water enters the heat pump system to absorb heat from a low-pressure side working medium to realize water supply preheating, and finally enters the heat storage system to absorb heat to complete a cycle.

(3) The waste heat recovery circulation adopts a simple heat pump (refrigeration) circulation, and the working process is as follows: the working medium of the heat pump is evaporated at low pressure, and then the steam is compressed into high-temperature high-pressure fluid by a compressor. The heat exchange is carried out with the heat supply circulating water in the heat exchanger, then the heat exchange is carried out through cooling and throttling, the heat exchange is changed into low-temperature low-pressure gas-liquid two-phase fluid, the low-temperature low-pressure gas-liquid two-phase fluid is evaporated and absorbed again, the circulation is completed, and a driving source of the heat pump (refrigeration) circulation is provided from the heat.

(4) And under the condition that heat supply is not needed and the environmental temperature is low enough, the power island cycle and the heat pump (refrigeration) cycle are isolated, and the power cycle adopts a pure Rankine cycle. The heat pump (refrigeration) cycle is not operating.

(5) The parameters and specific configuration of the power island system may vary with the type of heat source and design requirements. Such as: arrangements such as a reheat cycle may be employed to improve power subsystem efficiency.

(6) The working medium type, the operation parameters and the specific arrangement mode of the heat pump (refrigeration) system can be changed according to specific conditions. Such as: organic working media, water vapor, carbon dioxide, mixed working media and the like can be adopted as the working media; the arrangement modes of jet circulation, multi-stage circulation, regenerative circulation and the like can be adopted.

Embodiment 5, an operation method of a circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator is realized based on embodiments 1 to 4. The method specifically comprises the following steps:

the operation process comprises a power island circulation loop, a heat pump heat supply/refrigeration circulation loop and a heat supply loop, and specifically comprises the following steps:

power island circulation loop: the dead steam end of theturbine 6 passes through thecondenser 7, and high-pressure water pressurized by the booster pump enters the high-temperature evaporator 3 or theheat pump system 9 to absorb heat and raise the temperature to design parameters;

under the working condition of summer, the exhaust gas of theturbine 6 enters aheat pump system 9 after passing through acondenser 7, and theheat pump system 9 is used for realizing the recovery of the waste heat of the circulating water and heating the feed water; after preheating, the feed water enters a high-temperature evaporator 3 to complete a cycle;

under the working condition in winter, the exhaust gas of theturbine 6 directly enters the high-temperature evaporator 3 after passing through thecondenser 7, then enters theturbine 6 to do work through expansion, and the output power of the turbine is used for driving the generator to generate electricity to complete a cycle;

heat pump heating/cooling cycle circuit: under the working condition of summer, no heat supply demand exists, and under the condition of higher temperature in the daytime, the three-way control valve IA1 controls the heat pump heat supply/refrigeration circulation loop to be put into operation; the three-way control valve IIIA3 three-way control valve VA5 controls the condensed water to enter theheat pump system 9, and the circulating water waste heat is recycled through heat pump circulation to be used for preheating the condensed water; the temperature at night is low, the temperature of a cold end meets the high-efficiency operation requirement of the unit, and the three-way control valve IA1 is used for controlling to isolate the heat pump system; under the working condition in winter, the waste heat recovered from the circulating water by theheat pump system 9 is directly conveyed to the heatuser heat exchanger 12 by adjusting the three-way control valve IIA2, the three-way control valve IIIA3, the three-way control valve IVA4 and the three-way control valve VA5, so as to supply heat to users.

A heat supply loop: the heat pump working medium heats the heat supply circulating water through the high-temperaturewater storage tank 10 and the low-temperaturewater storage tank 11, and then the heat supply circulating water supplies heat to users through a heat supply pipe network; the heat supply circulating medium is generally water, but other media can be adopted according to actual needs.

According to the embodiment, according to the characteristics that solar energy resources are endowed with different resources in different seasons and in the morning and evening and circulating cooling water of a power island loop has a large number of low-grade heat sources, the heat pump subsystem is used for recovering the low-grade heat sources with considerable total amount in the circulating water, the power island is preheated in summer, and the heating requirement with certain load is realized in winter. The invention skillfully uses the heat pump principle, realizes comprehensive cascade utilization of energy on the premise of lower investment, realizes annual high-efficiency operation of the steam turbine island, and simultaneously completes considerable heat supply demand in winter, thereby better realizing the utilization efficiency of the energy.

It should be noted that the above cycle only indicates the simplest tower type photo-thermal power generation system, i.e. the combination of a simple heat pump and cogeneration, the system for practical engineering application will be more complicated, and in order to improve the cycle efficiency, the above power island cycle can also be replaced by a more complicated system such as primary reheating, secondary reheating, etc.; the heat pump (refrigeration) subsystem can also be replaced by systems such as jet circulation, multi-stage circulation, regenerative circulation and the like; auxiliary equipment can be added according to the needs. The present embodiment is still equivalent to or modified from the present embodiment as long as the combination of the tower-type photothermal power island cycle and the heat pump (refrigeration) cycle is not changed.

The above examples are only for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the above embodiments, it should 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. In particular, the above implementation shows only four layers of bionic vein structure, and the heat storage device with five layers and more or similar vein-shaped stacked beds has the same principle as the above implementation and should be included in the protection scope of the present invention.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims (7)

1. A circulating complementary combined heat and power system of a tower-type solar photo-thermal power generation refrigerator is characterized by comprising a tower-type solar heat collection system, a power island system and a heat pump refrigeration cycle waste heat recovery system;

wherein, the tower solar heat collecting system comprises a light condensing tower (1), a high-temperature heat accumulator (2), a high-temperature evaporator (3), a low-temperature evaporator (4) and a low-temperature heat accumulator (5) which are arranged in a heat accumulating loop in sequence, the low-temperature evaporator (4) provides required driving steam for a heat pump system of the heat pump refrigeration cycle waste heat recovery system, the high-temperature evaporator (3) provides required driving steam for a turbine (6) of a power island system, the turbine (6) does work and generates electricity, the dead steam end of the turbine (6) is connected with a condenser (7), the condenser (7) is respectively in circulating connection with a cooling tower (8) and a heat pump system, a condensed liquid outlet of the condenser (7) is connected with the high-temperature evaporator (3) through a power island water supply loop, the heat pump turbine is connected with an inlet end of the condenser, the condensed liquid outlet of the condenser is also connected with a heat pump loop of the heat pump refrigeration, the waste heat at the cold end of the power island system is converted into effective heat supply and output, and the effective heat supply is used for supplying heat to users and realizing the preheating of water supply.

2. The circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator according to claim 1, characterized in that: the heat pump refrigeration cycle waste heat recovery system comprises a heat pump system outlet, a high-temperature heat storage water tank (10), a heat user heat exchanger (12), a low-temperature heat storage water tank (11) and a heat pump system inlet which are sequentially arranged in a heat pump loop.

3. The circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator according to claim 2, characterized in that: the power island water supply loop is provided with a booster pump, a three-way control valve III and a three-way control valve II, the booster pump, the three-way control valve III and the three-way control valve II are sequentially arranged between a condenser (7) and a high-temperature evaporator (3), a three-way control valve IV and a three-way control valve V are arranged in the heat pump loop, the three-way control valve IV is arranged between a heat pump system (9) and a high-temperature water storage tank (10), the three-way control valve V is arranged between the heat pump system and a low-temperature water storage tank, the three-way control valve III is connected with the three-way control valve V through a pipeline, and the three-way control valve II is connected with the three.

4. The circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator according to claim 3, characterized in that: and a three-way control valve I is arranged in the heat storage loop, and an outlet of the high-temperature evaporator, an inlet of the low-temperature evaporator and an inlet of the low-temperature heat accumulator are connected through the three-way control valve I.

5. The circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator according to claim 1, characterized in that: the working medium of the heat pump system adopts organic working medium, water vapor, carbon dioxide or mixed working medium.

6. The circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator according to claim 1 or 5, characterized in that: the heat pump system adopts an injection type circulation, multi-stage circulation or regenerative circulation arrangement mode.

7. A method for operating a circulating complementary cogeneration system of a tower-type solar photo-thermal power generation refrigerator, which is realized based on the circulating complementary cogeneration system of claim 4,

the operation process comprises a power island circulation loop, a heat pump heat supply/refrigeration circulation loop and a heat supply loop, and specifically comprises the following steps:

power island circulation loop: the dead steam end of the turbine (6) passes through a condenser (7), and high-pressure water pressurized by a booster pump enters a high-temperature evaporator (3) or a heat pump system (9) to absorb heat and raise the temperature to design parameters;

under the working condition of summer, exhaust gas of the turbine (6) enters a heat pump system (9) after passing through a condenser (7), and the heat pump system (9) is used for realizing the recovery of the waste heat of circulating water and heating feed water; after preheating, the feed water enters a high-temperature evaporator (3) to complete a cycle;

under the working condition in winter, exhaust gas of the turbine (6) directly enters the high-temperature evaporator (3) after passing through the condenser (7), then enters the turbine (6) to do work through expansion, and the output power of the turbine is used for driving a generator to generate power to complete a cycle;

heat pump heating/cooling cycle circuit: under the working condition of summer, no heat supply demand exists, and under the condition of high temperature in the daytime, the three-way control valve I controls the heat pump heat supply/refrigeration circulation loop to be put into operation; the three-way control valve III and the three-way control valve V control the condensed water to enter a heat pump system (9), and the circulating water waste heat is recycled for preheating the condensed water by heat pump circulation; the temperature at night is low, the temperature of the cold end meets the high-efficiency operation requirement of the unit, and the heat pump system is isolated by the control of the three-way control valve I; under the working condition in winter, the heat pump system (9) directly conveys the waste heat recovered from the circulating water to the heat user heat exchanger (12) by adjusting the three-way control valve II, the three-way control valve III, the three-way control valve IV and the three-way control valve V, so as to supply heat to users;

a heat supply loop: the heat pump working medium realizes heating of the heat supply circulating water through the high-temperature hot water storage tank (10) and the low-temperature hot water storage tank (11), and then the heat supply circulating water supplies heat to users through a heat supply pipe network.

Images