Adiabatic compressed air energy storage system based on airflow-heat flow double-flow control and power adjusting method of adiabatic compressed air energy storage system

Abstract

The invention discloses an adiabatic compressed air energy storage system based on airflow-heat flow double-flow control and a power adjusting method thereof. The system comprises a multi-stage compression unit, an interstage heat conduction oil cooling unit, a high-pressure air storage device, a heat conduction oil heat storage device, an air conditioning module, an expansion unit, a central controller, a heat conduction oil adjusting system and a data acquisition feedback loop. In the compression process, the heat conduction oil recycles interstage compression heat and stores the interstage compression heat in the heat storage tank; in the energy releasing process, the central controller coordinates the flow of heat conduction oil and the flow of compressed air, the inlet temperature and mass flow of the expansion machine are controlled, and rapid adjustment and flexible response of output power are achieved. The system does not need gas afterburning, is high in energy efficiency, quick in response and wide in load application range, and is suitable for scenes of power grid frequency modulation, peak regulation, new energy consumption and the like.

Description

Technical Field

[0001] The present invention relates to a physical energy storage system, in particular to an adiabatic compressed air energy storage system based on airflow-heatflow dual flow control and a power regulation method thereof, belonging to the technical field of new energy and smart grid frequency and peak regulation. Background Art

[0002] As the proportion of renewable energy generation continues to increase, grid operations face increasing regulatory pressure. Maintaining grid stability while efficiently utilizing clean energy has become a key issue in the current energy transition. Compressed air energy storage, a typical large-scale physical energy storage technology, boasts large storage capacity, fast response, and strong terrain adaptability, and has been initially applied in many countries.

[0003] Conventional compressed air energy storage systems currently have the following shortcomings: First, compression heat is not fully recovered, resulting in low energy utilization; second, the expander inlet parameters are crudely controlled during the energy release phase, making it impossible to fine-tune power regulation based on grid demand; and third, some systems use supplemental combustion to increase temperature, which not only introduces additional fuel consumption but also hinders clean energy utilization. Therefore, a highly efficient, fast-adjusting, and responsive non-supplemental combustion adiabatic compressed air energy storage system is urgently needed to address these issues. Summary of the Invention

[0004] In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide an adiabatic compressed air energy storage system based on airflow-heat flow dual flow control and a power regulation method thereof, so as to achieve flexible power output and fast frequency response under different grid operating conditions.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] An adiabatic compressed air energy storage system based on airflow-heat flow dual flow control includes: a multi-stage compression unit 1, an interstage thermal oil cooling unit 2, a high-pressure air storage device 3, a thermal oil heat storage device 4, an air conditioning module 5, an expansion unit 6, a central controller 7, a thermal oil regulation system 8, and a data acquisition feedback loop 9;

[0007] The multi-stage compression unit 1 is composed of a multi-stage centrifugal compressor arranged in series. The outlet of each stage compressor is connected to the corresponding inter-stage thermal oil cooling unit 2 through an air duct. The inter-stage thermal oil cooling unit 2 is a shell and tube heat exchanger with an oil inlet pipe and an oil outlet pipe on the outside and a compressed air channel inside. The thermal oil flows outside the shell and tube for heat exchange.

[0008] The interstage thermal oil cooling unit 2 is composed of multiple heat exchangers, the number of which is determined according to the actual system requirements. Its thermal oil inlet and outlet are connected in series to the thermal oil heat storage device 4 via high-temperature and pressure-resistant pipelines. The thermal oil heat storage device 4 consists of multiple high-temperature storage tanks and low-temperature storage tanks, and is equipped with a thermal oil circulation pump, temperature sensor, liquid level gauge and safety valve;

[0009] The thermal oil regulating system 8 includes multiple electromagnetic control valves, an air heat exchanger, and a shell-and-tube air heater. The thermal oil heat storage device 4 is connected to the air heat exchanger for energy release of the thermal oil regulating system 8 via a heat supply main. The thermal oil is controlled by multiple electromagnetic control valves of the thermal oil regulating system 8 to flow into the shell-and-tube air heater located in the energy release path, where it undergoes air heating and heat exchange operations. The thermal oil then returns to the high-temperature storage tank and low-temperature storage tank of the thermal oil heat storage device 4 to form a closed loop.

[0010] The outlet of the final-stage shell-and-tube heat exchanger of the interstage thermal oil cooling unit 2 is directly connected to the high-pressure gas storage device 3 via the air main pipe. The high-pressure gas storage device 3 is an underground artificial chamber structure. A one-way check valve and a pressure regulating valve group are provided at the inlet of the gas storage pipeline. A pressure and temperature detection device is configured in the chamber. The chamber outlet pipe is connected to the air conditioning module 5.

[0011] The air conditioning module 5 includes multiple regulating valves, each of which has an inlet connected to the air storage chamber and an outlet connected to the air inlet of the air heat exchanger of the thermal oil conditioning system 8 and the inlet of the expander of the expansion unit 6, respectively. These valves are used to adjust the flow rate of compressed air through each stage of the expander and air heat exchanger at any time. The air heated by the air heat exchanger is transported through the main outlet pipe to the inlet flange interface of the multi-stage expansion unit 6. The expansion unit 6 includes one to three stages of axial flow expanders, the outlet of which is connected to a generator or energy conversion device.

[0012] The inlet of the data acquisition feedback loop 9 is connected to the air conditioning module 5 and the thermal oil regulation system 8 through industrial Ethernet, and the outlet of the data acquisition feedback loop 9 is connected to the central controller 7 through a data line to provide real-time temperature, pressure, and flow signal input. The central controller 7 dynamically adjusts the dual-path flow of air and thermal oil based on the change of grid load, and coordinates to adjust the temperature and mass flow of the expander inlet air, so as to realize flexible control of the system output power and rapid response to changes in grid frequency.

[0013] The multi-stage compression unit 1 includes a first compressor, a second compressor, and a third compressor arranged in series. The outlet of each stage compressor is connected to the shell and tube heat exchanger in the inter-stage thermal oil cooling unit 2 via a high-temperature air main pipe. The compressed air flows inside the shell, and the thermal oil runs countercurrently in the tube bundle. The compression heat is effectively recovered and reused by the thermal oil, thereby improving the round-trip efficiency of the system; each stage thermal oil cooling unit is provided with an independent oil inlet branch pipe and an oil return branch pipe, which are connected to the main circuit of the thermal oil heat storage device 4 through a tee junction, so that the system can control each stage thermal oil cooling unit separately, thereby improving the flexibility of the system; the compressed air outlet of each stage thermal oil cooler is connected to the inlet of the next stage compressor or the buffer tank interface via a short pipe of equal diameter, thereby forming a complete series multi-stage compression and segmented heat recovery structure; the compressor and thermal oil cooler are fixed on the same platform with a foundation support, and all connecting pipes compensate for thermal expansion through high-temperature flexible expansion joints, thereby improving the stability of the system.

[0014] The thermal oil storage device 4 includes multiple high-temperature storage tanks and low-temperature storage tanks, a variable-frequency driven thermal oil circulation pump, several high-temperature oil supply pipes and return oil pipes, control electric valves and pressure relief safety valves; the high-temperature storage tank adopts a double-layer insulation structure, is provided with a top return oil port and a bottom oil outlet, and is connected to the air heat exchanger of the thermal oil regulation system 8 at the front end of the expander through the main heating pipe; the thermal oil circulation pump and the control electric valve are installed in series on the oil outlet pipe to form a closed heating path with the flow regulated by the central controller 7; the thermal oil temperature control range is 240℃-320℃, and the pressure control range is 0.6-1.2MPa. Thermal storage energy monitoring and tank level sensors are set in the high-temperature storage tank and the low-temperature storage tank to detect the energy storage situation and liquid level in the tank. The central controller 7 judges the available residual heat capacity of the thermal oil according to the tank liquid level, thereby adjusting the thermal oil supply rhythm in the energy release stage.

[0015] The high-pressure gas storage device 3 is a vertical or horizontal underground artificial chamber with an inner wall lined with an anti-seepage sealing layer. The top of the chamber is provided with a gas inlet pipe, an emergency exhaust pipe, and a maintenance blind flange interface; the gas inlet pipe is connected to the compressed air outlet of the last-stage shell and tube heat exchanger of the interstage thermal oil cooling unit 2, and the inlet section is provided with a three-stage safety check valve, a set of automatic pressure regulating valve groups and an online pressure / temperature dual sensor; the gas outlet of the high-pressure gas storage device 3 is connected to the inlet section of the air conditioning module 5, and the connection section is provided with a lower pressure limit interlock signal, and energy release is prohibited when the chamber pressure is lower than the set value; the high-pressure gas storage device 3 is provided with a liquid-sealed drainage pipe and a monitoring instrument interface, with a pressure resistance level of 25MPa or above, which meets the requirements of continuous operation with variable load during the day and night.

[0016] The air conditioning module 5 includes a pneumatic control valve, an electric bypass valve, a Venturi flowmeter and a high-temperature platinum resistance temperature sensor controlled by a central controller 7. Its multiple inlets are connected to the outlet pipe of the high-pressure gas storage device 3, and the outlets enter the multiple air heat exchangers of the thermal oil regulation system 8 through insulated pipelines; the pneumatic control valve adjusts the mass flow of compressed air entering the main heat exchange path, and the Venturi flowmeter monitors the air mass flow in real time and feeds back to the central controller 7 to form a feedback loop; the communication rate of all valve signals with the central controller 7 is ≥10Hz, and the adjustment lag time is less than 3 seconds, which is used to accurately control the inlet state of the expander.

[0017] The expansion unit 6 is a two- to three-stage axial flow expander arranged in series. Its inlet is connected to the air heat exchanger of the thermal oil regulation system 8 via a flange, and its outlet is connected to the generator set. The expander is equipped with speed, bearing temperature, inlet pressure, and outlet temperature detection modules. The central controller 7 adjusts the air and thermal oil flow rates based on the expander's current speed and load, achieving stepless power regulation within a range of 50% to 110% of the rated output. A detection port is installed between each expansion stage to monitor flow anomalies. The expander responds to frequency regulation signals in less than 1.5 seconds, ensuring stable load compliance. This dual flow regulation of air and thermal oil enables load regulation over a wide range of system operations.

[0018] The thermal oil regulation system 8 also includes a variable frequency driven thermal oil pump, an electric proportional control valve, a redundant circuit control module and an oil temperature feedback circuit; the variable frequency driven thermal oil pump is arranged at the oil outlet of the thermal oil heat storage device 4, and the outlet is connected to the electric proportional control valve, which is connected to the heat medium inlet of the air heat exchanger; the electric proportional control valve receives a PWM or 0-10V control signal from the central controller 7 and controls the opening according to the set target oil flow rate; a heat medium temperature sensor is provided at the outlet of the air heat exchanger, and its signal is fed back to the central controller 7 to form a PID control closed loop; the thermal oil regulation system 8 supports a minimum adjustment step of 0.5% of the rated flow rate, and a maximum oil supply response time of ≤1.8 seconds.

[0019] The power regulation method of the adiabatic compressed air energy storage system based on airflow-heatflow dual flow control is characterized in that: the power regulation method is based on a PLC+SCADA architecture to build an energy management system, integrating functions such as data acquisition, path judgment, heat exchange ratio calculation and execution control; the control logic is refreshed once per second, and has real-time regulation capabilities;

[0020] During the energy storage phase of the system, the compressed air enters the gas storage chamber after being cooled, and the waste heat is introduced into high-temperature storage tanks for storage. The SCADA records the initial state of the heat source.

[0021] After entering the energy release phase, the system executes the following control strategies based on the grid load, frequency change rate and preset operating mode: frequency regulation priority mode, efficiency optimization mode, load tracking mode, and has automatic identification of operating condition switching logic;

[0022] When in frequency regulation priority mode, the central controller 7 adjusts the flow of thermal oil and air in real time according to the changes in grid frequency to quickly respond to power changes. The typical response period is 1 to 2 seconds.

[0023] In the efficiency optimization mode, the central controller 7 controls the thermal oil to operate within the optimal heat exchange range, reducing heat loss caused by overheating or overcooling of the thermal oil. In the load tracking mode, the central controller 7 smoothly adjusts the output power based on the predicted load, keeping the air flow and temperature in the optimal combination range to achieve stable energy output.

[0024] Mode switching uses sliding logic to avoid system disturbances caused by frequent start and stop of valves and pump groups, and supports dynamic switching of no less than 100 times within 24 hours.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] The compression heat is effectively recovered and reused by the thermal oil, avoiding heat loss and improving the system's round-trip efficiency. The controller synchronously adjusts the air and thermal oil through dual flow rates, and can adjust the output power within seconds. The system relies entirely on heat recovery during the energy release process and does not use natural gas supplementary combustion, which has high cleanliness. The dual adjustment of air and thermal oil can realize a wide range of operating load regulation. It supports intelligent switching of multiple operating modes to improve system stability and economy. Heat exchange, heat storage, and control are highly integrated, suitable for a variety of application scenarios such as new energy power stations, isolated grid islands, and thermal power frequency regulation transformation.

[0027] The present invention realizes dual closed-loop coordinated regulation of compression heat recovery and expansion control, and is an important supporting technology for grid-connected power grids with a high proportion of renewable energy. It has broad promotion prospects and industrial value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a system schematic diagram of an adiabatic compressed air energy storage system based on airflow-heat flow dual flow control and its power regulation method. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] like Figure 1As shown, the present invention is based on an adiabatic compressed air energy storage system with dual flow control of airflow and heat flow, comprising: a multi-stage compression unit 1, an inter-stage thermal oil cooling unit 2, a high-pressure air storage device 3, a thermal oil heat storage device 4, an air conditioning module 5, an expansion unit 6, a central controller 7, a thermal oil regulation system 8, and a data acquisition feedback loop 9;

[0031] The multi-stage compression unit 1 is composed of a multi-stage centrifugal compressor arranged in series. The outlet of each stage compressor is connected to the corresponding inter-stage thermal oil cooling unit 2 through an air duct. The inter-stage thermal oil cooling unit 2 is a shell and tube heat exchanger with an oil inlet pipe and an oil outlet pipe on the outside and a compressed air channel inside. The thermal oil flows outside the shell and tube for heat exchange.

[0032] The interstage thermal oil cooling unit 2 is composed of multiple heat exchangers, the number of which is determined according to the actual system requirements. Its thermal oil inlet and outlet are connected in series to the thermal oil heat storage device 4 via high-temperature and pressure-resistant pipelines. The thermal oil heat storage device 4 consists of multiple high-temperature storage tanks and low-temperature storage tanks, and is equipped with a thermal oil circulation pump, temperature sensor, liquid level gauge and safety valve;

[0033] The thermal oil regulating system 8 includes multiple electromagnetic control valves, an air heat exchanger, and a shell-and-tube air heater. The thermal oil heat storage device 4 is connected to the air heat exchanger for energy release of the thermal oil regulating system 8 via a heat supply main. The thermal oil is controlled by multiple electromagnetic control valves of the thermal oil regulating system 8 to flow into the shell-and-tube air heater located in the energy release path, where it undergoes air heating and heat exchange operations. The thermal oil then returns to the high-temperature storage tank and low-temperature storage tank of the thermal oil heat storage device 4 to form a closed loop.

[0034] The outlet of the final-stage shell-and-tube heat exchanger of the interstage thermal oil cooling unit 2 is directly connected to the high-pressure gas storage device 3 via the air main pipe. The high-pressure gas storage device 3 is an underground artificial chamber structure. A one-way check valve and a pressure regulating valve group are provided at the inlet of the gas storage pipeline. A pressure and temperature detection device is configured in the chamber. The chamber outlet pipe is connected to the air conditioning module 5.

[0035] The air conditioning module 5 includes multiple regulating valves, each of which has an inlet connected to the air storage chamber and an outlet connected to the air inlet of the air heat exchanger of the thermal oil conditioning system 8 and the inlet of the expander of the expansion unit 6, respectively. These valves are used to adjust the flow rate of compressed air through each stage of the expander and air heat exchanger at any time. The air heated by the air heat exchanger is transported through the main outlet pipe to the inlet flange interface of the multi-stage expansion unit 6. The expansion unit 6 includes one to three stages of axial flow expanders, the outlet of which is connected to a generator or energy conversion device.

[0036] The inlet of the data acquisition feedback loop 9 is connected to the air conditioning module 5 and the thermal oil regulation system 8 through industrial Ethernet, and the outlet of the data acquisition feedback loop 9 is connected to the central controller 7 through a data line to provide real-time temperature, pressure, and flow signal input. The central controller 7 dynamically adjusts the dual-path flow of air and thermal oil based on the change of grid load, and coordinates to adjust the temperature and mass flow of the expander inlet air, so as to realize flexible control of the system output power and rapid response to changes in grid frequency. Specific embodiments

[0038] The following describes the specific implementation of the adiabatic compressed air energy storage system and its power regulation method described in this invention, using a set of actual engineering parameters. This example, based on a non-supplementary-fired adiabatic compressed air energy storage system with a rated power of 300MW, demonstrates the system's operational structure and dynamic control methods throughout the entire process, from compression, heat storage, gas storage, to energy release.

[0039] When the grid load is low, the system enters a compression state, activating multi-stage compression unit 1. Filtered outside air is then boosted by the first through fourth-stage compressors. The compressed air at each stage enters a thermal oil cooler for cooling. Heat is absorbed by the thermal oil and transferred to thermal oil heat storage device 4 for storage. The compressed air ultimately enters high-pressure gas storage device 3 for storage at approximately 17 MPa and 45°C.

[0040] When the load on the grid increases or the frequency drops, the system responds quickly and starts the energy release process:

[0041] The central controller 7 determines the output power target based on the current grid frequency, predicted load and gas / heat storage status; controls the air conditioning module 5 to adjust the outlet air flow to the set value, for example, adjusting the air mass flow to 280kg / s; at the same time, controls the thermal oil regulation system 8 to adjust the thermal oil supply flow to 120kg / s and adjusts the proportional valve opening to 65%; high-pressure air enters the air heat exchanger, absorbs the heat of the thermal oil, and the air outlet temperature is stabilized at 290°C; the heated air enters the expansion unit 6 for staged expansion and work, driving the generator to output the set power, and the actual output power of the system reaches 290MW; after the heat exchange is completed, the thermal oil returns to the thermal oil heat storage device 4, completing the closed heat energy recovery.

[0042] When the grid frequency offset exceeds ±0.05Hz, the central controller 7 invokes a frequency response strategy, increasing the air flow rate to 15% / s and simultaneously adjusting the thermal oil flow rate. The system achieves a power increase from 200MW to 300MW in 1.2 seconds. During low-load periods at night, the central controller 7 maintains the air flow at 220kg / s and the thermal oil supply within the optimal heat exchange range to ensure maximum thermal efficiency. When wind power and photovoltaic power generation fluctuate significantly, the system slowly adjusts both air and thermal oil flow rates based on the predicted load curve, maintaining a stable output of 300±5MW and ensuring grid frequency stability. All operating mode transitions are accomplished using sliding control logic, ensuring smooth transitions between control variables and preventing sudden temperature changes from impacting the expander equipment.

Claims

1. Adiabatic compressed air energy storage system based on airflow-heat flow dual flow control, characterized by: include: A multi-stage compression unit (1), an inter-stage thermal oil cooling unit (2), a high-pressure gas storage device (3), a thermal oil heat storage device (4), an air conditioning module (5), an expansion unit (6), a central controller (7), a thermal oil regulating system (8), and a data acquisition feedback loop (9); The multi-stage compression unit (1) is composed of a multi-stage centrifugal compressor arranged in series, and the outlet of each stage compressor is connected to the corresponding inter-stage thermal oil cooling unit (2) through an air duct. The inter-stage thermal oil cooling unit (2) is a shell and tube heat exchanger, which is provided with an oil inlet pipe and an oil outlet pipe on the outside and a compressed air channel on the inside. The thermal oil flows outside the shell and tube for heat exchange. The interstage thermal oil cooling unit (2) is composed of a plurality of heat exchangers, the number of which is determined according to the actual system requirements. The thermal oil inlet and outlet are connected in series to the thermal oil heat storage device (4) via a high-temperature pressure-resistant pipeline. The thermal oil heat storage device (4) is composed of a plurality of high-temperature storage tanks and low-temperature storage tanks, and is equipped with a thermal oil circulation pump, a temperature sensor, a liquid level gauge and a safety valve. The thermal oil regulating system (8) includes a plurality of electromagnetic control valves, an air heat exchanger, and a shell-and-tube air heater. The thermal oil heat storage device (4) is connected to the air heat exchanger for energy release of the thermal oil regulating system (8) through a heat supply main. The thermal oil is controlled by the plurality of electromagnetic control valves of the thermal oil regulating system (8) to flow into the shell-and-tube air heater located in the energy release path to perform air heating and heat exchange operations, and then returns to the high-temperature storage tank and the low-temperature storage tank of the thermal oil heat storage device (4) to form a closed loop. The outlet of the final stage shell and tube heat exchanger of the interstage thermal oil cooling unit (2) is directly connected to the high-pressure gas storage device (3) via an air main pipe. The high-pressure gas storage device (3) is an underground artificial chamber structure. A one-way check valve and a pressure regulating valve group are provided at the inlet of the gas storage pipeline. A pressure and temperature detection device is provided in the chamber. The chamber outlet pipe is connected to the air conditioning module (5). The air conditioning module (5) includes a plurality of regulating valves, each regulating valve inlet is connected to the air storage chamber, and the outlet is respectively connected to the air inlet of the air heat exchanger of the thermal oil regulating system (8) and the inlet of the expander of the expansion unit (6), so as to adjust the flow rate of compressed air of each stage expander and air heat exchanger at any time. The air heated by the air heat exchanger is transported to the inlet flange interface of the multi-stage expansion unit (6) through the main outlet pipe. The expansion unit (6) includes one to three stages of axial flow expanders, and the outlet is connected to a generator or an energy conversion device. The inlet of the data acquisition feedback loop (9) is connected to the air conditioning module (5) and the thermal oil regulation system (8) through industrial Ethernet, and the outlet of the data acquisition feedback loop (9) is connected to the central controller (7) through a data line to provide real-time temperature, pressure, and flow signal input. The central controller (7) dynamically adjusts the dual-path flow of air and thermal oil based on the change of grid load, and coordinately adjusts the temperature and mass flow of the expander inlet air to achieve flexible control of the system output power and rapid response to changes in grid frequency.

2. The adiabatic compressed air energy storage system based on airflow-heatflow dual flow control according to claim 1, characterized in that: The multi-stage compression unit (1) comprises a first compressor, a second compressor, and a third compressor which are arranged in series. The outlet of each stage compressor is connected to the shell and tube heat exchanger in the inter-stage thermal oil cooling unit (2) via a high-temperature air main pipe. The compressed air flows inside the shell, and the thermal oil flows in countercurrent in the tube bundle. Each stage thermal oil cooling unit is provided with an independent oil inlet branch pipe and an oil return branch pipe, which are connected to the main circuit of the thermal oil heat storage device (4) through a tee. The compressed air outlet of each stage thermal oil cooler is connected to the inlet of the next stage compressor or the buffer tank interface via a short pipe of equal diameter, forming a complete series multi-stage compression and segmented heat recovery structure. The compressor and the thermal oil cooler are fixed on the same platform with a foundation support, and all connecting pipes are compensated for thermal expansion through high-temperature flexible expansion joints.

3. The adiabatic compressed air energy storage system based on airflow-heatflow dual flow control according to claim 1, characterized in that: The heat transfer oil heat storage device (4) includes a plurality of high-temperature storage tanks and low-temperature storage tanks, a variable frequency driven heat transfer oil circulation pump, a plurality of high-temperature oil supply pipes and oil return pipes, a control electric valve and a pressure relief safety valve; the high-temperature storage tank adopts a double-layer insulation structure, is provided with a top oil return port and a bottom oil outlet, and is connected to the air heat exchanger of the heat transfer oil regulation system (8) at the front end of the expander through a main heat supply pipeline; the heat transfer oil circulation pump and the control electric valve are installed in series on the oil outlet pipe to form a closed heat supply path with the flow rate regulated by the central controller (7); the temperature control range of the heat transfer oil is 240℃-320℃, and the pressure control range is 0.6-1.2MPa. Heat storage energy monitoring and tank level sensors are set in the high-temperature storage tank and the low-temperature storage tank to detect the energy storage situation and liquid level in the tank. The central controller (7) judges the available residual heat capacity of the heat transfer oil according to the tank liquid level, thereby adjusting the heat transfer oil supply rhythm in the energy release stage.

4. The adiabatic compressed air energy storage system based on airflow and heat flow dual flow control according to claim 1, characterized in that: The high-pressure gas storage device (3) is a vertical shaft or horizontal underground artificial chamber, the inner wall of which is lined with an anti-seepage sealing layer, and the top of the chamber is provided with a gas inlet pipe, an emergency exhaust pipe, and a maintenance blind flange interface; the gas inlet pipe is connected to the compressed air outlet of the last-stage shell and tube heat exchanger of the interstage thermal oil cooling unit (2), and the inlet section is provided with a three-stage safety check valve, a set of automatic pressure regulating valve groups, and an online pressure / temperature dual sensor; the gas outlet of the high-pressure gas storage device (3) is connected to the inlet section of the air conditioning module (5), and the connection section is provided with a pressure lower limit interlocking signal, and energy release is prohibited when the chamber pressure is lower than the set value; the high-pressure gas storage device (3) is provided with a liquid seal drainage pipe and a monitoring instrument interface, with a pressure resistance level of more than 25MPa, meeting the requirements of continuous operation with variable loads day and night.

5. The adiabatic compressed air energy storage system based on airflow-heatflow dual flow control according to claim 1, characterized in that: The air conditioning module (5) includes a pneumatic regulating valve, an electric bypass valve, a venturi flowmeter and a high-temperature platinum resistance temperature sensor controlled by a central controller (7), wherein multiple inlets are connected to the outlet pipe of the high-pressure gas storage device (3), and the outlets respectively enter multiple air heat exchangers of the thermal oil regulating system (8) through the insulation pipeline; the pneumatic regulating valve regulates the mass flow of compressed air entering the main heat exchange path, and the venturi flowmeter monitors the air mass flow in real time and feeds back to the central controller (7) to form a feedback loop; the communication rate of all valve signals with the central controller (7) is ≥10Hz, and the regulation lag time is less than 3 seconds, so as to accurately control the inlet state of the expander.

6. The adiabatic compressed air energy storage system based on airflow and heat flow dual flow control according to claim 1, characterized in that: The expansion unit (6) is an axial flow expansion unit arranged in series with two to three stages, the inlet of which is connected to the air heat exchanger of the heat transfer oil regulation system (8) through a flange, and the outlet is connected to the generator set; a speed, bearing temperature, inlet pressure and outlet temperature detection module is provided inside the expander, and a central controller (7) adjusts the dual flow of air and heat transfer oil according to the current speed and load state of the expander to achieve stepless power regulation within the rated output range of 50% to 110%; a detection port is provided between each expansion stage for monitoring flow abnormalities, and the time for the expander to respond to the frequency regulation signal is less than 1.5 seconds, and it has the ability to stably follow load changes.

7. The adiabatic compressed air energy storage system based on airflow and heat flow dual flow control according to claim 1, characterized in that: The heat transfer oil regulating system (8) also includes a variable frequency driven heat transfer oil pump, an electric proportional regulating valve, a redundant circuit control module and an oil temperature feedback circuit; wherein the variable frequency driven heat transfer oil pump is arranged at the oil outlet of the heat transfer oil heat storage device (4), the outlet is connected to the electric proportional regulating valve, and the electric proportional regulating valve is connected to the heat medium inlet of the air heat exchanger; the electric proportional regulating valve receives a PWM or 0-10V control signal from the central controller (7) and controls the opening according to the set target oil flow rate; the air heat exchanger outlet is provided with a heat medium temperature sensor, and its signal is fed back to the central controller (7) to form a PID control closed loop; the heat transfer oil regulating system (8) supports a minimum regulation step of 0.5% of the rated flow rate, and a maximum oil supply response time of ≤1.8 seconds.

8. The power regulation method of an adiabatic compressed air energy storage system based on airflow-heatflow dual flow control according to any one of claims 1 to 7, characterized in that: The power regulation method builds an energy management system based on the PLC+SCADA architecture, integrating functions such as data acquisition, path judgment, heat exchange ratio calculation and execution control. The control logic is refreshed once per second, with real-time regulation capabilities. During the energy storage phase of the system, the compressed air enters the gas storage chamber after being cooled, and the waste heat is introduced into high-temperature storage tanks for storage. The SCADA records the initial state of the heat source. After entering the energy release phase, the system executes the following control strategies based on the grid load, frequency change rate and preset operating mode: frequency regulation priority mode, efficiency optimization mode, load tracking mode, and has automatic identification of operating condition switching logic; When in frequency regulation priority mode, the central controller (7) adjusts the flow of thermal oil and air in real time according to the change of grid frequency to quickly respond to power changes, with a typical response period of 1 to 2 seconds; In the efficiency optimization mode, the central controller (7) controls the heat transfer oil to operate within the optimal heat exchange range, thereby reducing heat loss caused by overheating or overcooling of the heat transfer oil; in the load tracking mode, the central controller (7) smoothly adjusts the output power based on the predicted load, maintains the air flow and temperature within the optimal combination range, and achieves stable energy output; Mode switching uses sliding logic to avoid system disturbances caused by frequent start and stop of valves and pump groups, and supports dynamic switching of no less than 100 times within 24 hours.

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