A gas turbine combined cycle cold heat electricity hydrogen combined supply system coupling high-temperature heat storage and phase change cold storage and an operation control method thereof

Abstract

The application discloses a gas turbine combined cycle cold-heat-electricity-hydrogen combined supply system coupling high-temperature heat storage and phase change cold storage and an operation control method thereof. The system is composed of an inner subsystem of a power plant and an outer subsystem. The inner subsystem comprises a gas turbine combined cycle unit, a high-temperature heat storage unit and a steam collector, realizes shunt heat storage of high-temperature exhaust heat and flexible allocation of high-temperature steam, and the outer subsystem comprises a hydrogen production unit and a heating and cooling pipe network, and realizes efficient supply and cascade utilization of multiple energy forms in combination with a steam turbine, an absorption refrigeration, a mechanical refrigeration and a phase change cold storage device. The operation control method proposed by the application covers steps of parameter acquisition and demand prediction, steam distribution regulation and control, heat storage and heat release management, hydrogen production load adjustment, waste heat coupling utilization, cold and heat energy adjustment and cold storage balance, and is supplemented by hierarchical optimization control of an energy management platform, so that the multi-energy collaborative supply and flexible peak regulation of electric power, heat energy, cold energy and hydrogen energy can be realized.

Description

Technical Field

[0001] This invention belongs to the field of gas turbine combined cycle cogeneration technology, and relates to the energy cascade utilization and multi-energy complementary control of gas turbine combined cycle. In particular, it relates to a gas turbine combined cycle cogeneration system and its operation control method that couples high-temperature thermal storage and phase change cold storage, which is used to improve the peak-shaving flexibility, comprehensive energy efficiency and multi-energy coordinated supply capability of gas-fired power plants. Background Technology

[0002] With the increasing demand for clean energy and low-carbon development, power plants face pressure to transform and upgrade their energy structure, improve energy efficiency, and utilize energy efficiently. To achieve sustainable development, power plants need to adopt low-carbon technologies to reduce carbon emission intensity and improve energy utilization efficiency. Currently, for cogeneration units used for industrial heating, the limited market development and the severely constrained supply of industrial steam limit the development of industrial heating-type cogeneration units and the improvement of their energy efficiency.

[0003] In recent years, combined cooling, heating, and power (CCHP) systems have attracted increasing attention due to the growing prominence of energy issues. On the one hand, CCHP systems utilize energy in a cascade manner, resulting in high energy efficiency; on the other hand, natural gas-based CCHP systems can effectively reduce greenhouse gas and air pollutant emissions. For example, Chinese utility model patent CN205638705U discloses a CCHP system utilizing LNG for ice making and natural gas as fuel. However, the high price of natural gas has imposed certain constraints on the development of CCHP systems based on natural gas as a primary energy source.

[0004] In terms of operating conditions, combined cycle gas turbine units are prone to power output reduction in high-temperature summer environments. Studies show that for every 1°C increase in ambient temperature, the average output power of the gas turbine decreases by approximately 0.6%, and efficiency decreases by approximately 0.18%. This phenomenon not only leads to insufficient power generation capacity but also affects steam production, thereby reducing the stability of downstream heating and cooling supply. Simultaneously, limited by the radius of cold energy transport and cold storage capacity, centralized cooling systems often struggle to meet the simultaneous cooling needs of long-distance, multi-regional, and multi-user environments. Traditional cold storage devices have limited power density and insufficient cold release rates, further restricting the balancing and regulation of large-scale user-side loads.

[0005] In terms of energy utilization, existing CCHP systems generally suffer from the limitation of "single input, single output," primarily revolving around the path of natural gas combustion → electricity output → waste heat energy supply. While this model has some effectiveness in improving primary energy utilization, it lacks effective coupling in multi-energy complementarity and the coordinated utilization of renewable energy. With the rapid increase in the proportion of new energy sources, the grid's demand for flexible resource regulation has significantly increased. Traditional CCHP units lack flexibility and have slow response times, making them unsuitable for the dispatching requirements of future multi-energy systems. Furthermore, existing technologies still have shortcomings in energy management and dispatching. Most CCHP systems have failed to fully incorporate advanced demand response mechanisms and multi-energy flow dispatching strategies, lacking a unified optimization platform for overall coordination of electricity, heat, cooling, and other energy sources. This leads to systems often focusing on meeting single energy demands during operation, neglecting the coupling relationships and mutual constraints between different energy forms, resulting in overall efficiency decline and insufficient economic viability.

[0006] In summary, existing combined cooling, heating, and power (CCHP) systems generally suffer from high dependence on natural gas, limited peak-shaving capacity, reduced output under high-temperature conditions in summer, insufficient centralized cooling transmission radius, and a lack of multi-energy complementarity and dispatch mechanisms. Therefore, how to improve the overall energy efficiency, peak-shaving flexibility, and multi-energy coordinated supply capacity of the units while ensuring a stable steam supply is an urgent technical problem to be solved. Summary of the Invention

[0007] (a) Purpose of the invention

[0008] To address the aforementioned deficiencies and shortcomings of existing technologies, this invention aims to provide a combined cycle gas turbine system for integrated cooling, heating, power, and hydrogen production, coupled with high-temperature thermal storage and phase change cold storage, and its operation and control method. Based on the energy utilization concept of "temperature matching and cascade utilization," it proposes high-temperature thermal storage and deep peak-shaving technologies on the power plant's gas turbine combined cycle source side to ensure stable steam supply and improve power plant output capacity. Simultaneously, it changes the traditional single-input / single-output production method and direct combustion utilization of natural gas. On the energy consumption side, it proposes centralized heating (cooling) and methanol-steam reforming hydrogen production technologies to complete hydrogen production while also addressing downstream cooling needs, constructing a multi-energy synergistic path integrating electricity, hydrogen, heat, and cooling. Furthermore, it configures phase change cold storage units and centralized cooling networks on the energy consumption side to improve the storage and release power of cold energy and long-distance transmission capacity; and relies on multi-energy flow scheduling and demand response modules to achieve dynamic optimization allocation between grid load regulation and multi-energy supply. Thus, while ensuring a stable steam supply, it achieves enhanced unit flexibility, improved overall energy efficiency, and multi-energy complementary power supply goals.

[0009] (II) Technical Solution

[0010] To achieve the objective of this invention and solve its technical problems, the present invention adopts the following technical solution:

[0011] The first objective of this invention is to provide a combined cycle gas turbine system for combined cooling, heating, power, and hydrogen, which couples high-temperature thermal storage and phase change cold storage. This system is used in combined cycle gas turbine power plants to utilize the generated steam as the primary energy carrier, achieving multi-energy synergistic supply and cascaded energy utilization of electricity, heat, cold energy, and hydrogen, as well as flexible peak shaving. It includes at least the following components:

[0012] An internal subsystem of a power plant includes at least a gas turbine combined cycle unit, a high-temperature thermal storage unit, and a steam collection and distribution system. The gas turbine combined cycle unit comprises a gas turbine, a waste heat boiler, and a steam turbine. The high-temperature flue gas pipeline of the gas turbine is equipped with a diversion regulating valve group. The main flue gas flows into the waste heat boiler, while a portion of the flue gas is diverted to the high-temperature thermal storage unit according to peak-shaving requirements. The steam turbine, while generating electricity, provides extractable high-temperature, high-pressure steam through its main steam external supply interface, which is then fed into the downstream steam collection and distribution system. The high-temperature thermal storage unit… The thermal unit is equipped with a heat storage tank and a steam generator. The heat storage tank absorbs heat from the diverted flue gas through a heat exchange device for high-temperature heat storage. After releasing heat, the flue gas returns to the flue gas side of the waste heat boiler. When the load fluctuates, the steam generator uses the stored heat to generate high-temperature steam and delivers it to the steam collection and distribution unit located downstream. The inlet end of the steam collection and distribution unit is connected to the main steam external supply interface of the steam turbine and the steam generator. The outlet end forms an external steam supply interface and is equipped with a steam distribution and metering unit, which is used to distribute the external steam to various energy-consuming units outside the power plant as needed.

[0013] An external subsystem of a power plant includes at least a hydrogen production unit and a heating and cooling network. The steam inlet of the hydrogen production unit is connected to the steam distribution and metering unit, and hydrogen is produced by methanol-water vapor thermochemical reforming using the distributed high-temperature and high-pressure steam. The hydrogen production side is connected to the hydrogen storage and distribution or refueling end. The heating and cooling network integrates a steam turbine, an absorption refrigeration unit, a refrigeration unit, and a phase change cold storage unit. The steam inlet of the steam turbine is simultaneously connected to the low-temperature steam outlet of both the steam distribution and metering unit and the hydrogen production unit in a switchable manner. The exhaust end is connected to the high-pressure generator of the absorption refrigeration unit and is driven to drive the refrigeration unit. The exhaust side of the high-pressure generator provides heat to the heat user end through a heat exchange device, and the generated return water is returned to the power plant. The chilled water outlet of the evaporator in the absorption refrigeration unit is connected to the downstream phase change cold storage unit, and the cold storage power density is increased by the equipped refrigeration unit. The downstream chilled water pipeline is connected to the cold user end, and the generated low-temperature return water is transported to the evaporator.

[0014] The second objective of this invention is to provide an operation control method for the aforementioned gas turbine combined cycle combined cooling, heating, power, and hydrogen supply system, which, when implemented, includes at least the following control steps:

[0015] SS1. Parameter Acquisition and Demand Forecasting: Real-time acquisition of operating data of various components inside the power plant and load parameters of various components outside the power plant, combined with grid dispatch signals and user demand for heat, cold and hydrogen, to form multi-energy demand forecasts;

[0016] SS2. Steam Distribution and Flow Control: Based on demand forecasts and the principles of temperature matching and cascade utilization, determine the combined cycle unit output, the heat storage and release power of the high-temperature thermal storage unit, and the distribution ratio of the steam collection and distribution unit. Dynamic distribution of external steam supply is achieved through the steam distribution and metering unit.

[0017] SS3. Thermal storage and release process control: When the power grid is under low load or there is surplus power, the control diversion regulating valve introduces part of the high-temperature flue gas from the gas turbine into the high-temperature thermal storage unit for thermal storage; when the power grid is under peak load or the demand for cold, heat and hydrogen increases, the steam generator in the thermal storage unit is started to release the stored energy and generate high-temperature steam to compensate for the steam collection and distribution unit, so as to achieve decoupling of power and steam supply and flexible peak regulation;

[0018] SS4. Coupling of hydrogen production and by-product steam utilization: Based on the peak shaving demand of the power grid and the demand for hydrogen, the operating load of the hydrogen production unit is dynamically adjusted. By controlling the methanol feed rate, steam supply rate and reaction temperature, the hydrogen production power can be flexibly adjusted. The rapid adjustment of the hydrogen production load provides auxiliary frequency regulation for the power grid. At the same time, the medium and low temperature steam generated in the hydrogen production process is recovered and sent to the steam turbine of the heating and cooling pipeline network as driving steam to realize the cascade utilization of energy.

[0019] SS5. Heating, Cooling and Cold Storage Regulation: Based on the spatiotemporal distribution characteristics of user-side heating and cooling loads, and through real-time monitoring of hot water pipes, cold water pipes and return water temperature and flow, the operating conditions of absorption chillers and refrigeration units are dynamically controlled to achieve linkage with phase change cold storage devices. Under base load conditions, absorption chillers provide stable cooling capacity, while under peak load conditions, the deep cooling mode of the refrigeration units is activated to improve cooling capacity output and cold storage density. At the same time, the supply and return water temperatures and flow rates of the heating and cooling pipe networks are adjusted to achieve time-shifted regulation and peak-valley balance of heat and cold energy.

[0020] (III) Technical Effects

[0021] Compared with the prior art, the combined cycle gas turbine cooling, heating, power and hydrogen supply system and its operation control method of the present invention, which couples high-temperature thermal storage and phase change cold storage, have the following beneficial and significant technical effects:

[0022] (1) This invention achieves decoupled operation of power peak shaving and stable supply of multiple energy sources by constructing a coupling mechanism of high-temperature thermal storage of gas turbine and steam cascade utilization. The system uses the waste heat of gas turbine exhaust for high-temperature thermal storage, and independently generates high-temperature steam through the thermal storage unit during the grid peak shaving period, ensuring the continuous and stable operation of energy-consuming units such as hydrogen production, heating, and cooling. At the same time, the gas turbine can perform deep peak shaving within its rated power range, which significantly improves the peak shaving flexibility of the power plant and the grid adaptability, and provides an effective means of regulation for the large-scale grid connection of renewable energy.

[0023] (2) This invention constructs a three-stage cascade utilization path for steam thermal energy, realizing the full utilization of energy quality at each stage. High-temperature and high-pressure steam is first used for methanol steam reforming to produce hydrogen. The medium- and low-temperature steam (150-200℃) after hydrogen production drives a steam turbine to generate electricity. The turbine exhaust further drives an absorption refrigeration unit to produce cold, forming a complete energy conversion chain of hydrogen production-power generation-refrigeration, which significantly improves the overall energy utilization efficiency of the system, enhances the utilization efficiency of primary energy, and improves the economic efficiency of the system.

[0024] (3) This invention achieves the spatiotemporal coordinated optimization of four energy types—cold, heat, electricity, and hydrogen—by integrating phase change cold storage technology with intelligent multi-energy flow scheduling. The phase change cold storage device stores cold energy during off-peak periods and releases it during peak periods, effectively mitigating cold load fluctuations. Furthermore, the energy management and control platform integrates deep peak shaving, demand response, and multi-energy flow scheduling functions, enabling cross-system global optimization and real-time control under conditions of multi-source input and multi-load demand, thereby significantly improving the overall energy utilization efficiency of the system, the grid regulation capability, and the continuity and reliability of multi-energy supply. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a combined cycle gas turbine cooling, heating, power and hydrogen supply system that couples high-temperature thermal storage and phase change cold storage according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the hydrogen production unit structure in this invention;

[0027] Figure 3 This is a flowchart illustrating the operation control method of a gas turbine combined cycle cooling, heating, power, and hydrogen cogeneration system according to an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached drawings: 1-Gas turbine, 2-Waste heat boiler, 3-Steam turbine, 4-Flow control valve group, 5-High temperature heat storage unit, 51-Heat storage tank, 52-Steam generator, 6-Steam collection and distribution device, 7-Hydrogen production unit, 71-Methanol preheater, 72-Methanol vaporizer, 73-Reform reactor, 74-Gas-liquid separator, 75-Purification unit, 76-Distribution valve group, 8-Heating and cooling pipeline network, 9-Steam turbine, 10-Absorption refrigeration unit, 11-Refrigeration unit, 12-Phase change cold storage device, 13-Switching valve, 14-High pressure generator, 15-Evaporator, 16-Heat exchange device, 17-Inlet cooling module, 18-Three-way switching valve. Detailed Implementation

[0029] This invention aims to provide a combined cycle gas turbine system for combined cooling, heating, power, and hydrogen, coupled with high-temperature thermal storage and phase change cold storage, and its operation and control method. Based on the energy utilization concept of "temperature matching and cascaded utilization," it is used in gas turbine combined cycle power plant scenarios to achieve multi-energy coordinated supply and cascaded energy utilization of electricity, heat, cold energy, and hydrogen, as well as flexible peak shaving, using the generated steam as the main energy carrier. To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. The described embodiments are some, but not all, embodiments of this invention, and are exemplary, intended to explain the invention, and should not be construed as limiting the invention.

[0030] Example 1: Gas turbine combined cycle cooling, heating, power and hydrogen cogeneration system

[0031] like Figure 1 As shown, as a specific example, the combined high-temperature thermal storage and phase change cold storage gas turbine combined cycle cogeneration system of the present invention is used in gas turbine combined cycle power plant scenarios to achieve multi-energy coordinated supply and cascaded energy utilization of electricity, heat, cold energy and hydrogen, as well as flexible peak shaving, using the generated steam as the main energy carrier. This includes:

[0032] The power plant's internal subsystems include a gas turbine combined cycle unit, a high-temperature thermal storage unit, and a steam collection and distribution system. The gas turbine combined cycle unit consists of a gas turbine 1, a waste heat boiler 2, and a steam turbine 3. The high-temperature flue gas pipeline of gas turbine 1 is equipped with a diversion regulating valve group 4. The main flue gas flows into the waste heat boiler 2, while a portion of the flue gas is diverted to the high-temperature thermal storage unit 5 according to peak-shaving requirements. While generating electricity, the steam turbine 3 provides extractable high-temperature, high-pressure steam through its main steam external supply interface and feeds it into the downstream steam collection and distribution system 6. The high-temperature thermal storage unit 5 is equipped with thermal storage... The heat storage tank 51 and the steam generator 52 are used. The heat storage tank 51 absorbs the heat of the diverted flue gas through a heat exchange device for high-temperature heat storage. After releasing heat, the flue gas returns to the flue gas side of the waste heat boiler 2. When the load fluctuates, the steam generator 52 uses the heat storage to generate high-temperature steam and delivers it to the steam collection and distribution unit 6 located downstream. The inlet end of the steam collection and distribution unit 6 is connected to the main steam external supply interface of the steam turbine 3 and the steam generator 52. The outlet end forms an external steam supply interface and is equipped with a steam distribution and metering unit, which is used to distribute the external steam to various energy-consuming units outside the power plant as needed.

[0033] The power plant's external subsystem includes a hydrogen production unit 7 and a heating and cooling network 8. The steam inlet of the hydrogen production unit 7 is connected to the steam distribution and metering unit of the steam collector and distributor 6. The distributed high-temperature, high-pressure steam is used for methanol-water vapor thermochemical reforming to produce hydrogen. The hydrogen production side is connected to the hydrogen storage and distribution or refueling end. The heating and cooling network 8 integrates a steam turbine 9, an absorption chiller 10, a chiller unit 11, and a phase change cold storage device 12. The steam inlet of the steam turbine 9 is simultaneously connected to the steam distribution and metering unit of the steam collector and distributor 6 and the hydrogen production unit 7 via a switching valve 13 in a switchable manner. The low-temperature steam outlet and exhaust end are connected to the high-pressure generator 14 of the absorption refrigeration unit 10 and are driven by the refrigeration unit 11. The exhaust side of the high-pressure generator 14 provides heat to the heat user end through the heat exchange device 16. The generated return water is returned to the power plant. The chilled water outlet of the evaporator 15 in the absorption refrigeration unit 10 is connected to the downstream phase change cold storage device 12 and the cold storage power density is increased by the equipped refrigeration unit 11. The downstream chilled water pipeline is connected to the cold user end, and the generated low-temperature return water is transported to the evaporator 15 of the absorption refrigeration unit 10.

[0034] In this embodiment of the invention, the gas turbine 1 is equipped with an intake cooling module 17 for regulating the inlet air temperature of the compressor. This module is coupled to the chilled water pipeline of the evaporator 15 in the absorption refrigeration unit 10 via its built-in heat exchange device. The intake cooling module 17 is activated when the intake air temperature exceeds a preset threshold, effectively increasing the power output of the gas turbine 1 during peak summer electricity demand periods, enhancing the unit's peak-shaving margin, and achieving synergistic optimization of intake cooling and phase-change cold storage. Preferably, the intake cooling module 17 can further integrate a temperature sensor and a flow regulating valve to ensure precise control of the cooling process, avoiding increased energy consumption due to over-cooling, thereby improving the overall system's energy efficiency and low-carbon emission performance while ensuring steam extraction stability.

[0035] In this embodiment of the invention, the heat storage tank 51 of the high-temperature heat storage unit 5 uses high-temperature molten salt or solid particles as the heat storage medium, with a heat storage temperature range of 400-800℃. Its heat storage capacity is determined according to the power plant's peak shaving duration and load adjustment range. The heat storage tank 51 is equipped with a high-temperature resistant multi-stage heat exchange component and is coupled to the diversion regulating valve group 4 on the high-temperature flue gas pipeline of the gas turbine 1 and the flue gas side of the waste heat boiler 2 through an external pipeline. This component is used to divert part of the flue gas heat to the heat storage tank 51 for charging, under the premise of meeting the safe inlet temperature of the waste heat boiler 2, thereby achieving efficient heat storage during the unit's off-peak operation. The steam generator 52 is connected to the heat storage tank 51 through an independent heat exchange circuit and flexibly releases the stored heat according to the fluctuation of the grid load and the change in external steam demand, generating a stable high-temperature steam supply. This decouples the power plant operation from the steam supply, improves the system's operational flexibility and stability under multiple operating conditions, and enhances the grid's peak shaving capacity and the continuity and reliability of the steam supply.

[0036] In this embodiment of the invention, high-temperature heat storage and deep peak-shaving technology are employed. Specifically, the flue gas volume is adjusted by controlling the high-temperature exhaust gas flow rate of gas turbine 1, and the heat from the high-temperature flue gas is stored at high temperature. This stored heat can be used to regulate the turbine load, ensuring efficient unit operation while improving the generator set's flexibility under varying operating conditions. It also ensures the stability of downstream steam supply. Meanwhile, the operating performance of the gas turbine is easily affected by changes in ambient temperature. For every 1°C increase in ambient temperature, its output power and power generation efficiency decrease by approximately 0.6% and 0.18%, respectively. Hot summer months are peak periods for electricity demand; reducing the inlet air temperature of the gas turbine compressor can effectively increase unit output and enhance the unit's peak-shaving margin.

[0037] Furthermore, the diversion regulating valve group 4 of the high-temperature flue gas pipeline of gas turbine 1 is preferably connected to the flue gas temperature, pressure and oxygen sensors, and achieves proportional opening regulation through closed-loop communication with the energy management control platform. Under the condition that the flue gas at the inlet of waste heat boiler 2 is not lower than the acid dew point temperature threshold, part of the flue gas is diverted to the high-temperature heat storage unit 5 for heat storage. The diversion regulating valve group 4 is equipped with a bypass return pipeline and an emergency shut-off valve, which is used to switch to a safe operation mode when the unit is under low load or the flue gas parameters are abnormal, so as to avoid low-temperature corrosion and thermal stress shock. Moreover, the diversion control of the diversion regulating valve group 4 is comprehensively determined based on the unit load and the external steam demand to achieve dynamic optimization and adjustment of the flue gas diversion ratio.

[0038] In this embodiment of the invention, the inlet end of the steam collector and distributor 6 is connected to the main steam external supply interface of the steam turbine 3 and the steam generator 52 in the high-temperature thermal storage unit, respectively, for centralized collection and pressure stabilization of high-temperature steam from different sources. Preferably, a steam distribution and metering unit is provided at its outlet end. The steam distribution and metering unit is preferably equipped with a multi-way regulating valve group and a flow metering device. According to the real-time monitoring of hydrogen production, heating load and cooling load requirements, and based on a multi-way control algorithm, the distribution ratio of each steam path is dynamically adjusted. The flow metering device records the temperature, pressure, flow rate and enthalpy value of each steam path in real time and uploads them to the energy management and control platform in real time to realize the refined allocation and management of steam resources.

[0039] In this embodiment of the invention, the steam turbine 9 in the power plant's external subsystem is a small back-pressure or extraction-back-pressure turbine unit. Its steam inlet is connected to the low-temperature steam outlet of the steam collection and distribution unit 6 and the hydrogen production unit 7 via a switching valve 13 to utilize extracted steam or waste heat steam for work. Its exhaust end is directly connected to the high-pressure generator 14 of the absorption refrigeration unit 10 to realize the cascade utilization of the turbine exhaust heat energy. At the same time, it is connected to the compressor of the refrigeration unit 11 via a coupling at the turbine shaft end. The steam turbine 9 is preferably equipped with an adjustable nozzle structure and / or a variable frequency speed control device to achieve dynamic adjustment of power output under external load fluctuations. Through real-time monitoring and closed-loop control of steam pressure, temperature and flow, the operating conditions of the steam turbine 9 are matched with those of the absorption refrigeration unit 10 and the refrigeration unit 11.

[0040] In this embodiment of the invention, by employing centralized heating and cooling technology, high-temperature, high-pressure steam from a steam turbine can first be used to generate electricity via a steam turbine, and then drive a steam-type lithium bromide chiller for cooling. To maintain efficient system operation and broaden the range of user cooling load demands, the cooling subsystem is equipped with a phase change cold storage unit. This unit further cools the lithium bromide chilled water using a large temperature difference centrifugal water chiller, thereby increasing the cold storage / release power of the cold storage unit and the chilled water transport distance. A reasonable power supply area and transport distance for the centralized heating and cooling substation are fundamental to ensuring efficient system operation; therefore, determining a reasonable power supply area is particularly important. The division of power supply areas varies depending on the load characteristics of the land parcel, regional planning, and the layout of transportation routes. The power supply radius of the heating and cooling substation is influenced by many factors; the larger the scale of the heating and cooling substation, the greater the temperature difference between the supply and return water, and the larger the power supply radius, but also the higher the transport energy consumption.

[0041] In this embodiment of the invention, the absorption refrigeration unit 10 is a single-effect or double-effect unit using lithium bromide (LiBr) solution as the working fluid. It includes a high-pressure generator 14 and an evaporator 15. The steam inlet of the high-pressure generator 14 is connected to the exhaust pipe of the steam turbine 9 to receive heat from the turbine exhaust at a working pressure of 0.4~0.9 MPa to drive solution regeneration. Its exhaust side provides heat to the external heating network through a heat exchange device 16, achieving cascade utilization of steam energy. The 7~12℃ chilled water outlet generated by the evaporator 15 is connected to the downstream phase change cold storage device 12 to form a cold storage circuit. A three-way switching valve 18 is installed to form a series-parallel composite arrangement with the downstream refrigeration unit 11. At base load, the absorption refrigeration unit handles the main cooling capacity, while at peak load or low steam supply, the refrigeration unit 11 compensates and reduces the evaporation temperature to obtain 3~8℃ chilled water. ℃ chilled water, through a large temperature difference cold network strategy, improves the cold storage power density and cold storage capacity of the phase change cold storage device, reduces the chilled water circulation flow rate and extends the chilled water transportation distance, to meet the cooling needs of users in long distances.

[0042] In this embodiment of the invention, the phase change cold storage device 12 uses paraffin, fatty acids, or inorganic salt hydrates as the phase change cold storage material, with a phase change temperature range of -5 to 15 ℃, and adopts a matrix-type microcapsule / plate encapsulation structure to improve the heat transfer area and heat transfer coefficient; the chilled water outlet pipe of the evaporator 15 in the absorption refrigeration device 10 is equipped with a three-way switching valve 18, one of which is directly coupled to the phase change cold storage device 12, and the other is connected to the downstream refrigeration unit 11 for deep cooling and then connected to the phase change cold storage device 12. The three-way switching valve 18 achieves closed-loop control through closed-loop communication with the energy management control platform, and switches the operating mode according to the changes in cold network load and grid dispatch instructions. Under the base load condition, the absorption refrigeration device 10 directly supplies cooling to the phase change cold storage device 12. Under peak load or high-intensity cold load, the refrigeration unit 11 further cools the device to enhance the cold storage density and long-distance transportation capacity.

[0043] In this embodiment of the invention, the heating and cooling pipeline network 8 adopts a four-pipe design to achieve independent distribution and energy recovery of hot water and chilled water. It includes a hot water supply pipe, a hot water return pipe, a chilled water supply pipe, and a chilled water return pipe. At key nodes of the pipeline network, regulating valve groups and circulating pump groups are equipped to adjust the temperature difference and flow rate of the supply and return water according to the user's heat and cold load requirements. The hot water supply temperature is 60~90 ℃, and the chilled water supply temperature is 3~8 ℃. The pipeline network coverage radius is determined according to the heat and cold load density and transportation economy. At the same time, a metering device is configured to monitor the energy consumption of each user in real time to achieve dynamic adjustment.

[0044] In this embodiment of the invention, the hydrogen production unit 7 preferably employs a methanol-steam thermochemical reforming device. Its core is to achieve a reforming reaction between methanol and steam under medium- and low-temperature conditions, which not only yields high-purity hydrogen but also recovers and utilizes byproduct steam during the process, thereby achieving cascaded energy utilization and optimized coupling. Specifically, the reforming reaction zone is filled with a Cu / ZnO / Al2O3 catalyst, the reaction temperature is controlled within the range of 200~300 ℃, the reaction pressure is controlled within the range of 1.0~2.0 MPa, and the molar ratio of steam to methanol is controlled within the range of 1.2~2.5. After the reforming reaction, a hydrogen-rich mixed gas is generated and separated and purified downstream. The accompanying medium- and low-temperature steam (150~200 ℃) is transported to the steam turbine 9 of the heating and cooling pipeline network to provide a driving heat source, achieving efficient recovery and cascaded utilization of steam thermal energy during the hydrogen production process.

[0045] More specifically, such as Figure 2 As shown, the hydrogen production unit 7 in this embodiment of the invention includes at least a methanol preheater 71, a methanol vaporizer 72, a reforming reactor 73, a gas-liquid separator 74, and a purification unit 75. High-temperature, high-pressure steam from the steam collector and distributor 6 is divided into two paths by a distribution valve group 76. One path is fed into the reforming reactor 73 as a reaction feedstock, and the other path is fed into the methanol vaporizer 72 to vaporize the preheated methanol. After releasing heat, the vaporized methanol is transported as medium-low temperature steam to the steam turbine of the heating and cooling pipeline network. The vaporized methanol is then fed into the reforming reactor 73. The product gas from the reforming reactor 73 is fed into the hot side of the methanol preheater 71 for cooling and then further fed into the gas-liquid separator 74. The cold side of the methanol preheater 71 is fed with methanol feedstock and unreacted methanol separated by the gas-liquid separator 74. The preheated methanol is then fed into the methanol vaporizer 72. The mixed gas separated by the gas-liquid separator 74 is fed into the downstream purification unit 75, where it undergoes pressure swing adsorption (PSA). High-purity hydrogen is obtained by purification using PSA (Polyhydrogen Sulfate) or membrane separation, and by-product gases are recycled as fuel or recycle gas.

[0046] In a further preferred embodiment, the gas turbine combined cycle combined cooling, heating, power, and hydrogen power system of the present invention can also be equipped with an energy management and control platform. This platform adopts a hierarchical distributed architecture and integrates at least a deep peak shaving module, a demand response module, and a multi-energy flow scheduling module. It also achieves bidirectional communication connections with key monitoring and control points in both the power plant's internal and external subsystems. Specifically, the deep peak shaving module communicates with the grid dispatching terminal to receive grid load forecasts and peak shaving commands. By coordinating multiple control variables, including at least the output of the gas turbine combined cycle unit, the heat storage and release of the high-temperature thermal storage unit, the steam distribution ratio of the steam collector, and the load of the hydrogen production unit, it achieves flexible peak shaving of the power plant output on intraday and interday scales. Simultaneously, it ensures the stability of steam supply to meet the dual constraints of grid flexibility requirements and diversified energy demands from users. The demand response module collects real-time demand data for electricity, hydrogen, heat, and cooling energy from users through the communication network, and establishes a multi-timescale load forecasting model based on this data. It then implements peak shaving and valley filling strategies and demand-side management to ensure the supply and demand balance of multi-energy loads. The multi-energy flow scheduling module interacts in real-time with the steam collector, steam distribution and metering device, heating and cooling pipeline network, and hydrogen production unit. It also combines at least temperature, pressure, flow rate, and enthalpy monitoring data to dynamically allocate steam flow direction through a multi-variable control algorithm, achieving multi-energy coordinated supply of electricity, heat, cooling, and hydrogen energy and refined configuration of energy flow.

[0047] Example 2: Operation Control Method

[0048] Based on the system structure described in Example 1, Example 2 further provides an operation control method for the aforementioned integrated high-temperature thermal storage and phase change cold storage gas turbine combined cycle cogeneration system. This method uses temperature matching and cascaded utilization as its core energy management principles, aiming to achieve multi-energy coordinated supply of electricity, heat, cold energy, and hydrogen, ensuring a dual balance between the power plant's flexible peak-shaving capacity and user-side energy demand. Its control process is based on real-time monitoring data inside and outside the system, relying on an energy management and control platform for multi-module coordinated scheduling to achieve dynamic optimization and stability assurance of operation. Figure 3 As shown, the method mainly includes the following steps:

[0049] SS1. Parameter Acquisition and Demand Forecasting:

[0050] By deploying sensors on key components inside the power plant (gas turbines, waste heat boilers, steam turbines, high-temperature thermal storage units, steam collection and distribution units, etc.) and on energy-consuming units outside the power plant (hydrogen production units, steam turbines, absorption refrigeration units, phase change thermal storage units, and heating and cooling pipe networks), real-time operational data such as temperature, pressure, flow rate, and enthalpy are collected. Combined with grid dispatch signals and the heat, cold, and hydrogen demands of user loads, multi-energy load forecasts are generated. This forecasting model considers both short-term fluctuations and long-term trends, providing a reliable data foundation for subsequent steam distribution and system optimization.

[0051] SS2. Steam Distribution and Flow Control:

[0052] Based on demand forecasting results and following the principles of temperature matching and cascaded utilization, the power output of the gas turbine combined cycle unit, the heat storage and release strategy of the high-temperature thermal storage unit, and the allocation ratio of the steam collection and distribution unit are determined. A multi-energy flow scheduling module dynamically allocates externally supplied steam to achieve coordinated steam supply between the hydrogen production unit, steam turbine, and absorption refrigeration unit. Preferably, the multi-energy flow scheduling module utilizes a multivariable control algorithm, combined with real-time collected temperature, pressure, flow rate, and enthalpy parameters, to perform closed-loop control of the multi-path regulating valve group of the steam distribution unit, ensuring precise allocation of steam resources and meeting the dual constraints of system energy balance and economical operation.

[0053] SS3. Control of heat storage and release processes:

[0054] When the power grid is under low load or has surplus power, the control valve directs some of the high-temperature exhaust gas from the gas turbine into the high-temperature thermal storage unit for heat storage. When the power grid is under peak load or the demand for cold, heat, and hydrogen increases, the steam generator in the thermal storage unit is activated to release stored energy, generating high-temperature steam to compensate for the high-temperature steam entering the steam collector, thereby achieving decoupling of power and steam supply and flexible peak shaving. Preferably, the charging and releasing of heat in the high-temperature thermal storage unit is based on the power grid load curve. During periods of low power demand, the control valve is prioritized to direct the exhaust gas from the gas turbine into the thermal storage tank for charging. During periods of high power demand or a sudden increase in demand-side load, the steam generator is controlled to release the stored heat, which is then used to supplement external steam supply via the steam collector, thereby achieving decoupling of power plant operation from external steam supply demand and flexible peak shaving of the system.

[0055] SS4. Coupling utilization of hydrogen production and by-product steam:

[0056] Based on the grid's peak-shaving demand and hydrogen demand, the operating load of the hydrogen production unit is dynamically adjusted. By controlling the methanol feed rate, steam supply, and reaction temperature, flexible regulation of hydrogen production power is achieved. Rapid adjustment of the hydrogen production load provides auxiliary frequency regulation for the grid. Simultaneously, the medium- and low-temperature steam generated during hydrogen production is recovered and fed into the heating and cooling network's steam turbine as driving steam, achieving energy cascade utilization. Preferably, the methanol reforming reaction conditions are controlled within the range of 200–300 ℃ and 1.0–2.0 MPa pressure, with the steam / methanol molar ratio maintained between 1.2 and 2.5. The feed ratio is dynamically corrected by real-time monitoring of the reactor outlet gas composition and conversion rate. At the same time, the 150–200 ℃ medium- and low-temperature steam produced as a byproduct of hydrogen production is controlled to enter the steam turbine drive end of the heating and cooling network, achieving an organic combination of hydrogen energy production and steam waste heat recovery.

[0057] SS5. Heating, cooling and cold storage regulation:

[0058] Based on the spatiotemporal distribution characteristics of user-side heating and cooling loads, and by real-time monitoring of hot water pipes, cold water pipes, and return water temperature and flow rate, the operating conditions of the absorption chiller and refrigeration unit are dynamically controlled to achieve linkage with the phase change cold storage device. Under base load conditions, the absorption chiller provides stable cooling capacity, while under peak load conditions, the refrigeration unit activates deep-cooling mode to improve cooling output capacity and cold storage density. Simultaneously, the supply and return water temperatures and flow rates of the heating and cooling network are adjusted to achieve time-shifted regulation and peak-valley balance of heating and cooling energy. Preferably, a three-way switching valve is installed on the cold source side. One path of chilled water directly enters the phase change cold storage device for cold storage via the absorption chiller, while the other path is deep-cooled by the refrigeration unit before entering the phase change cold storage device to provide lower-temperature cold storage during peak cooling loads. A closed-loop control is formed through temperature sensors, flow meters, and water level sensors to achieve dynamic matching between cooling capacity and cold network conditions.

[0059] SS6. Safety Constraints and Emergency Fault Handling:

[0060] During system operation, key operating parameters and statuses of each subsystem are monitored in real time. When equipment failure, excessive operating parameters, or potential safety risks are detected, the energy management and control platform triggers a tiered emergency response procedure, implementing measures such as load transfer, activation of backup equipment, and bypass switching to ensure system stability and the continuity and reliability of multi-energy supply.

[0061] In summary, the operation control method described in Example 2, based on the system architecture of Example 1, forms a complete operational logic from parameter acquisition, demand forecasting, steam scheduling, thermal storage and release, hydrogen production coupling, to heating and cooling supply linkage and emergency response. This method not only ensures the flexibility of internal power plant operation and adaptability to external loads, but also realizes the multi-energy coordinated supply of electricity, heat, cold energy and hydrogen, as well as the cascaded and efficient utilization of energy, demonstrating significant energy conservation, emission reduction and system optimization value.

[0062] The objectives of this invention have been fully and effectively achieved through the above embodiments. Those skilled in the art will understand that this invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments described above. Although the invention has been described with reference to what is currently considered the most practical and preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments, and any modifications that do not depart from the functional and structural principles of the invention will be included within the scope of the claims.

Claims

1. A combined cycle gas turbine system for combined cooling, heating, power, and hydrogen supply, coupled with high-temperature thermal storage and phase change cold storage, characterized in that, At least including: An internal subsystem of a power plant includes a gas turbine combined cycle unit, a high-temperature thermal energy storage unit, and a steam collection and distribution system. The gas turbine combined cycle unit comprises a gas turbine, a waste heat boiler, and a steam turbine. The high-temperature flue gas pipeline of the gas turbine is equipped with a diversion regulating valve group. The main flue gas flows into the waste heat boiler, while a portion of the flue gas is diverted to the high-temperature thermal energy storage unit according to peak demand. The steam turbine generates electricity while simultaneously supplying high-temperature, high-pressure steam through the main steam external supply interface and feeding it into the downstream steam collection and distribution system. The high-temperature thermal energy storage unit comprises a thermal energy storage tank and a steam generator. The thermal energy storage tank absorbs heat from the diverted flue gas through a heat exchange device for high-temperature thermal energy storage. After releasing heat, the flue gas returns to the waste heat boiler flue gas side. The steam generator utilizes the thermal energy storage to generate high-temperature steam during load fluctuations and delivers it to the steam collection and distribution system. The inlet end of the steam collection and distribution system is connected to the main steam external supply interface of the steam turbine and the steam generator, while the outlet end forms an external steam supply interface and is equipped with a steam distribution and metering unit. An external subsystem of a power plant includes a hydrogen production unit and a heating and cooling network. The steam inlet of the hydrogen production unit is connected to a steam collector and distributor, using the distributed high-temperature and high-pressure steam for methanol-water vapor thermochemical reforming to produce hydrogen. The heating and cooling network integrates a steam turbine, an absorption refrigeration unit, a refrigeration unit, and a phase change cold storage unit. The steam inlet of the steam turbine is connected in a switchable manner to the medium- and low-temperature steam outlet of the steam collector and distributor and the hydrogen production unit. The exhaust end is connected to the high-pressure generator of the absorption refrigeration unit and drives the refrigeration unit. The exhaust side of the high-pressure generator provides heat to heat users through a heat exchange device. The chilled water outlet of the evaporator in the absorption refrigeration unit is connected to the phase change cold storage unit, and the cold storage power density is increased by the equipped refrigeration unit. The downstream chilled water pipeline is connected to the cold users. The gas turbine is equipped with an intake cooling module for regulating the temperature of the air at the compressor inlet. It is coupled to the chilled water pipeline of the evaporator in the absorption refrigeration unit through its built-in heat exchange device. The intake cooling module is activated when the intake air temperature is higher than a preset threshold, so as to effectively increase the power output of the gas turbine during the peak electricity load demand period in summer and enhance the peak shaving margin of the unit. The inlet of the steam collector and distributor is connected to the main steam external supply interface of the steam turbine and the outlet of the steam generator in the high-temperature thermal storage unit, respectively. It is used to centrally collect and stabilize high-temperature steam from different sources. A steam distribution and metering unit is provided at its outlet. The steam distribution and metering unit is equipped with a multi-way regulating valve group and a flow metering device. According to the real-time monitoring of the steam demand, heating load demand and cooling load demand of the hydrogen production unit, and based on the multi-way control algorithm, the distribution ratio of each steam is dynamically adjusted. The flow metering device records the temperature, pressure, flow rate and enthalpy value of each steam in real time. The data is uploaded to the energy management and control platform in real time to realize the refined allocation and management of steam resources.

2. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1, characterized in that, The high-temperature thermal storage unit uses high-temperature molten salt or solid particles as the thermal storage medium, with a thermal storage temperature range of 400~800 ℃. The thermal storage capacity is determined according to the power plant's peak shaving duration and load adjustment range. The thermal storage tank is equipped with a high-temperature resistant multi-stage heat exchange component, which is coupled to the diversion regulating valve group on the high-temperature flue gas pipeline of the gas turbine and the flue gas side of the waste heat boiler through an external pipeline. This is used to divert part of the flue gas heat to the thermal storage tank for charging, provided that the safe temperature of the waste heat boiler inlet is met. The steam generator is connected to the thermal storage tank through an independent heat exchange circuit and flexibly releases the stored heat according to the fluctuation of the power grid load and the change of external steam demand to generate a stable high-temperature steam supply.

3. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1 or 2, characterized in that, The diversion regulating valve group of the high-temperature flue gas pipeline of the gas turbine is communicatively connected to the flue gas temperature, pressure and oxygen sensors, and achieves proportional opening regulation through closed-loop communication with the energy management control platform. Under the condition that the flue gas at the inlet of the waste heat boiler is not lower than the acid dew point temperature threshold, part of the flue gas is diverted to the high-temperature heat storage unit for heat storage. The diversion regulating valve group is equipped with a bypass return pipeline and an emergency shut-off valve to switch to a safe operation mode when the unit is under low load or the flue gas parameters are abnormal, so as to avoid low-temperature corrosion and thermal stress shock. Furthermore, the diversion control of the diversion regulating valve group is comprehensively judged based on the unit load demand and the external steam supply demand to achieve dynamic optimization and adjustment of the flue gas diversion ratio.

4. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1, characterized in that, The steam turbine is a small back-pressure or extraction-back-pressure turbine unit. Its steam inlet is connected to the low-temperature steam outlet of the steam distribution and metering unit and the hydrogen production unit in a switchable manner to utilize extracted steam or waste heat steam for work. The exhaust end is directly connected to the high-pressure generator of the absorption refrigeration unit, and is also connected to the compressor of the refrigeration unit through a coupling at the turbine shaft end. The steam turbine is equipped with an adjustable nozzle structure and / or a variable frequency speed control device to achieve dynamic adjustment of power output under external load fluctuations. Through real-time monitoring and closed-loop control of steam pressure, temperature and flow, the operating conditions of the steam turbine are matched with those of the absorption refrigeration unit and the refrigeration unit.

5. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1, characterized in that, The absorption refrigeration unit is a single-effect or double-effect unit using lithium bromide solution as the working fluid. It is equipped with a high-pressure generator and an evaporator. The steam inlet of the high-pressure generator is connected to the exhaust pipeline of the steam turbine to receive the heat from the turbine exhaust at a working pressure of 0.4~0.9 MPa to drive solution regeneration. Its exhaust side provides heat to the external heating network through a heat exchange device. The 7~12 ℃ chilled water outlet of the evaporator is connected to the downstream phase change cold storage unit to form a cold storage loop. It is connected to the downstream refrigeration unit in a series-parallel composite arrangement by setting a three-way switching valve. At base load, the absorption refrigeration unit undertakes the main cooling capacity. At peak load or low steam supply, the refrigeration unit compensates and reduces the evaporation temperature to obtain chilled water at 3~8 ℃. The cold storage power density and cold storage capacity of the phase change cold storage unit are improved by the large temperature difference cold network strategy.

6. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1 or 5, characterized in that, The phase change cold storage device uses paraffin, fatty acids, or inorganic salt hydrates as phase change cold storage materials, with a phase change temperature range of -5 to 15℃. It adopts a matrix-type microcapsule / plate encapsulation structure to improve the heat transfer area and heat transfer coefficient. In the absorption refrigeration device, a three-way switching valve is installed on the chilled water outlet pipe of the evaporator. One path is directly coupled to the phase change cold storage device, and the other path is connected to the downstream refrigeration unit for deep cooling before being connected to the phase change cold storage device. The three-way switching valve achieves closed-loop control through closed-loop communication with the energy management control platform and switches the operating mode according to the changes in cold network load and grid dispatch instructions. Under base load conditions, the absorption refrigeration device directly supplies cooling to the phase change cold storage device. Under peak load or high-intensity cold load conditions, the refrigeration unit further cools the device to enhance the cold storage density and long-distance transportation capacity.

7. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1, characterized in that, The heating and cooling pipeline network adopts a four-pipe design to achieve independent distribution of hot water and chilled water, including hot water supply pipe, hot water return pipe, chilled water supply pipe, and chilled water return pipe. Regulating valve groups and circulating pump groups are equipped at key nodes of the network to adjust the temperature difference and flow rate of the supply and return water according to the user's heating and cooling load demand. The hot water supply temperature is 60~90 ℃, and the chilled water supply temperature is 3~8 ℃. The network coverage radius is determined based on the heating and cooling load density and transportation economy. At the same time, metering devices are configured to monitor the user's energy consumption in real time for dynamic adjustment.

8. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 1, characterized in that, The hydrogen production unit is a methanol steam thermochemical reforming unit. The reforming reaction zone is filled with a Cu / ZnO / Al2O3 catalyst. The reaction temperature is controlled within the range of 200~300 ℃, the reaction pressure is controlled within the range of 1.0~2.0 MPa, and the molar ratio of steam to methanol is controlled within the range of 1.2~2.

5. After the reforming reaction, a hydrogen-rich mixed gas is generated and then separated and purified downstream. The medium-low temperature steam with a temperature range of 150~200 ℃ generated after hydrogen production is transported to the steam turbine of the heating and cooling pipeline network to provide a driving heat source.

9. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 8, characterized in that, The hydrogen production unit includes at least a methanol preheater, a methanol vaporizer, a reforming reactor, a gas-liquid separator, and a purification unit. High-temperature and high-pressure steam from the steam distribution and metering unit is divided into two streams by a distribution valve. One stream is fed into the reforming reactor as a reaction feedstock, and the other stream is fed into the methanol vaporizer to vaporize the preheated methanol. After releasing heat, the vaporized methanol is transported to the steam turbine of the heating and cooling pipeline network in the form of medium- and low-temperature steam. The vaporized methanol is fed into the reforming reactor. The product gas from the reforming reactor is fed into the hot side of the methanol preheater for cooling and then further fed into the gas-liquid separator. The cold side of the methanol preheater is fed with methanol feedstock and unreacted methanol separated by the gas-liquid separator. The preheated methanol is fed into the methanol vaporizer. The mixed gas separated by the gas-liquid separator is fed into the downstream purification unit, where it is purified by pressure swing adsorption or membrane separation to obtain high-purity hydrogen. The by-product gas is recycled as fuel or recycle gas.

10. The gas turbine combined cycle cogeneration system for cooling, heating, power, and hydrogen supply according to claim 8, characterized in that, It also includes an energy management and control platform, which adopts a hierarchical distributed architecture and integrates at least a deep peak-shaving module, a demand response module, and a multi-energy flow scheduling module. This platform also achieves bidirectional communication connections with key monitoring and control points in both the power plant's internal and external subsystems. The deep peak shaving module is also connected to the grid dispatch terminal to receive grid load forecasts and peak shaving instructions. By coordinating multiple control variables, including at least the output of the gas turbine combined cycle unit, the heat storage and release of the high-temperature thermal storage unit, the steam distribution ratio of the steam collection and distribution unit, and the load of the hydrogen production unit, it can achieve flexible peak shaving of the power plant output while ensuring the stability of the external steam supply. The demand response module collects real-time demand data for electricity, hydrogen, heat, and cooling energy from the user side through the communication network, and establishes a multi-time-scale load forecasting model based on this data. It then implements peak shaving and valley filling strategies and demand-side management strategies to ensure the supply and demand balance of multi-energy loads. The multi-energy flow scheduling module interacts in real time with the steam collection and distribution unit, the steam distribution and metering unit, the heating and cooling pipeline network, and the hydrogen production unit. It also combines at least temperature, pressure, flow rate, and enthalpy monitoring data to dynamically allocate the steam flow direction through a multi-variable control algorithm, thereby achieving multi-energy coordinated supply and refined configuration of energy flow for electricity, heat, cold energy, and hydrogen.

11. A method for operating and controlling a gas turbine combined cycle cogeneration system according to any one of claims 1 to 10, characterized in that, It should include at least the following control steps: SS1. Real-time acquisition of operating data of various components inside the power plant and load parameters of various components outside the power plant, combined with grid dispatch signals and user demand for heat, cold and hydrogen loads, to form multi-energy demand forecasts; SS2. Based on the demand forecast results and the principles of temperature matching and cascade utilization, determine the output of the combined cycle unit, the heat storage and release power of the high-temperature thermal storage unit, and the distribution ratio of the steam collection and distribution unit, and realize the dynamic distribution of external steam supply through the steam distribution and metering unit; SS3. When the power grid is under low load or there is surplus power, the control diversion regulating valve introduces part of the high-temperature flue gas from the gas turbine into the high-temperature thermal storage unit for heat storage; when the power grid is under peak load or the demand for cold, heat and hydrogen increases, the steam generator in the thermal storage unit is started to release the stored energy and generate high-temperature steam to compensate for the steam collection and distribution unit, so as to achieve decoupling of power and steam supply and flexible peak regulation. SS4. Based on the peak shaving demand of the power grid and the demand for hydrogen, the operating load of the hydrogen production unit is dynamically adjusted. By controlling the methanol feed rate, steam supply rate and reaction temperature, the hydrogen production power can be flexibly adjusted. The rapid adjustment of the hydrogen production load provides auxiliary frequency regulation for the power grid. At the same time, the medium and low temperature steam generated in the hydrogen production process is recovered and sent to the steam turbine of the heating and cooling pipeline network as driving steam to realize the cascade utilization of energy. SS5. Based on the spatiotemporal distribution characteristics of user-side heating and cooling loads, and by real-time monitoring of hot water pipes, cold water pipes, and return water temperature and flow rate, the operating conditions of absorption chillers and chiller units are dynamically controlled. Under base load conditions, absorption chillers provide stable cooling capacity, while under peak load conditions, the chiller units are activated in deep cooling mode to improve cooling capacity output and cold storage density. At the same time, the supply and return water temperatures and flow rates of the heating and cooling pipe networks are adjusted to achieve time-shifted regulation and peak-valley balance of heating and cooling energy.

12. The operation control method according to claim 11, characterized in that, In step SS2, the steam distribution and metering unit uses a multivariable control algorithm, combined with real-time collected pressure, temperature, flow rate and enthalpy data, to dynamically adjust the multi-way regulating valve group at the outlet of the steam collector and distributor, ensuring that the distribution of steam among the hydrogen production unit, steam turbine and absorption refrigeration unit meets the dual constraints of energy balance and economic operation.

13. The operation control method according to claim 11, characterized in that, In step SS3, the heat charging and discharging scheduling of the high-temperature thermal storage unit is based on the grid load curve. During periods of low electricity demand, the diversion regulating valve is prioritized to introduce the gas turbine exhaust into the thermal storage tank for charging. During periods of high electricity demand or sudden increases in demand-side load, the steam generator is controlled to release the stored heat and supplement the external steam supply through the steam collection and distribution device, thereby decoupling the power plant operation from the external steam supply demand and enabling flexible peak shaving of the system.

14. The operation control method according to claim 11, characterized in that, In step SS4, the methanol reforming reaction conditions are controlled within the range of 200–300 °C and 1.0–2.0 MPa, and the steam / methanol molar ratio is maintained between 1.2 and 2.

5. The feed ratio is dynamically corrected by real-time monitoring of the reactor outlet gas composition and conversion rate. At the same time, the low-temperature steam at 150–200 °C produced as a byproduct of hydrogen production is controlled to enter the steam turbine drive end of the heating and cooling pipeline network, thereby achieving an organic combination of hydrogen energy production and steam waste heat recovery.

15. The operation control method according to claim 11, characterized in that, In step SS5, a three-way switching valve is installed on the cold source side. One path of chilled water goes directly into the phase change cold storage device through the absorption refrigeration unit, while the other path goes through the refrigeration unit for deep cooling before entering the phase change cold storage device, so as to provide cold storage at a lower temperature during peak cooling load. A closed-loop control is formed through temperature sensors, flow meters and water level sensors to achieve dynamic matching between cooling capacity and cold network conditions.

16. The operation control method according to claim 11, characterized in that, It also includes steps SS6 for safety constraints and emergency response to faults. By monitoring the operating status and key parameters of each subsystem in real time, when equipment failure, parameter over-limit, or safety risks are detected, a graded emergency response procedure is executed, and the system is kept stable by load transfer and the deployment of backup equipment.

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