An integrated production, storage and utilization system based on pressure energy power generation

Abstract

The present invention relates to an integrated production, storage and utilization system based on pressure energy power generation, including an existing natural gas system, an energy management subsystem for intelligently managing the order of power consumption and power storage, and a power generation subsystem based on a dual-rotor expander, an energy storage subsystem and an energy use subsystem sharing an AC bus; the existing natural gas system includes a high-pressure gas transmission pipeline, an existing pressure regulating system and a medium-pressure urban pipe network connected in sequence; the power generation subsystem includes a dual-rotor expander and a generator connected thereto; a branch is drawn out on the inlet pipeline of the existing pressure regulating system, the dual-rotor expander is connected to the branch, and the natural gas of the drainage part drawn out through the branch is depressurized by the dual-rotor expander and regulated by the pressure regulator, and then connected to the outlet of the existing pressure regulating system and merged into the medium-pressure urban pipe network. The system combines energy supply, energy storage and energy use, and uses pressure energy to generate electricity, which can promote the recovery and utilization of pressure energy wasted in pressure regulation in various types of urban gas stations.

Description

Technical Field

[0001] The present invention relates to the technical field of energy recovery, conversion and utilization, and in particular to an integrated production, storage and utilization system based on pressure energy power generation. Background Art

[0002] In order to meet the energy needs of urban development and improvement of residents' quality of life, my country has built 8.0-12.0MPa ultra-high pressure long-distance pipelines and 4.0MPa high-pressure urban gas transmission and distribution pipelines. After the high-pressure natural gas is gradually reduced to 0.4MPa at the load center, it is distributed to end users through the medium-pressure municipal pipeline network.

[0003] According to statistics, the national natural gas consumption exceeded 280 billion cubic meters in 2018, of which pipeline natural gas accounted for about 73%. Theoretically, when the 10MPa natural gas in the long-distance pipeline is reduced to 0.4MPa through the pressure regulating equipment, about 49W of energy can be released per cubic meter. If the energy released during the pressure regulation of these natural gas is utilized, about 13 billion kW·h of electricity can be recovered. It is estimated that the scale of natural gas consumption in my country will reach 500 billion cubic meters in 2030, and the pressure energy released after pressure regulation during transportation can generate 23 billion kW·h of electricity per year.

[0004] Although in theory the pressure energy released by natural gas during pressure regulation and transmission can be converted into a large amount of electricity, there are not many successful cases of converting pressure energy into electricity. Since the recycling of pressure energy released during the pressure regulation process was not considered in the early planning and construction of urban gas pressure regulating stations, and the automation and intensiveness of the equipment in the pressure regulating stations were relatively high, the power load of the equipment in the stations was relatively small; in addition, the industrial layout and geographical conditions around the pressure regulating stations were limited, and there were few surrounding enterprises, which made it impossible to consume the electricity converted from the surplus pressure energy released by the pressure regulation, and thus the promotion and application of projects that use the electricity converted from pressure energy were relatively few. However, with the promotion and use of electric vehicles and electric vehicles, charging devices such as charging piles have become a rigid demand, coupled with the need to save resources and reduce energy consumption and emissions. Therefore, it is very necessary to recycle the pressure energy released during the pressure regulation process in various types of urban gas stations and convert it into electricity, and to store and utilize it. Summary of the invention

[0005] In order to overcome the technical problems existing in the prior art, the present invention provides an integrated production, storage and utilization comprehensive utilization system based on pressure energy power generation, which aims to recycle and utilize the pressure energy released by natural gas pressure regulation to generate electricity, and organically coordinate the electricity generated by the pressure energy with the self-use electricity of the pressure regulating station, power storage, external charging, emergency power consumption resistor cabinet, etc., and use the city power system as a supplement to construct a comprehensive utilization system with production, storage and utilization balanced and integrated, so as to realize the combination of pressure energy power generation and city power to power the equipment and new energy charging piles in the station, and achieve an integrated utilization method of peak shaving and valley filling through energy storage batteries and emergency power consumption resistor cabinets.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A production, storage and utilization integrated comprehensive utilization system based on pressure energy power generation, the system comprises an existing natural gas system, a power generation subsystem based on a dual-rotor expander, an energy storage subsystem, an energy use subsystem and an energy management subsystem for intelligently managing the power consumption of the energy use subsystem and the power storage sequence of the energy storage subsystem; the existing natural gas system comprises a high-pressure gas transmission pipeline, an existing pressure regulating system and a medium-pressure urban pipe network connected in sequence; the power generation subsystem comprises a dual-rotor expander and a generator connected thereto; a branch is led out on the inlet pipeline of the existing pressure regulating system, the dual-rotor expander is connected to the branch, and the natural gas of the drainage part led out through the branch is reduced in pressure by the dual-rotor expander and regulated by the pressure regulator, and then connected to the outlet of the existing pressure regulating system and merged into the medium-pressure urban pipe network, and at the same time, the pressure released by the natural gas pressure reduction can drive the dual-rotor expander to generate power, thereby driving the generator to generate electricity; the generator, the energy storage subsystem and the energy use subsystem share an AC bus;

[0008] Furthermore, the flow rate of the existing pressure regulating system is 8000~10000Nm 3 / h, inlet pressure 3.7MPa, inlet temperature 15℃, outlet pressure 0.35MPa; the natural gas flow rate of the branch is 2500Nm 3 / h; inlet pressure 1.8MPa, inlet temperature 15°C, after the dual-rotor expander does work and reduces the pressure, the outlet pressure is 0.73MPa, and the outlet temperature is -29°C.

[0009] Furthermore, the energy storage subsystem includes a rectifier, an energy storage battery and an inverter connected in sequence; the rectifier rectifies the AC power output by the generator set into DC power and stores it in the energy storage battery; the inverter converts the DC power output by the rectifier or the energy storage battery into AC power with stable voltage and frequency, and then outputs it to the energy consumption subsystem.

[0010] Furthermore, the rectifier power is 20kW; the energy storage battery is composed of a group of 100kWh battery stacks with a rated total capacity of 108.8kWh, and is composed of 680 50Ah lithium batteries, 680×3.2×50=108.8kWh; the energy storage system conversion efficiency is about 92%, and the actual power of the system is 108.8kWh×0.92=100kWh; the inverter power is 100kW.

[0011] Furthermore, the energy storage subsystem is connected to the energy management subsystem via an AC bus; the energy management subsystem includes a connected AC contactor, a PLC controller, an energy management system and a current detection device; the energy management subsystem dynamically controls the output power of the inverter through an intelligent control strategy according to the load conditions, and intelligently dispatches the power between pipeline natural gas pressure energy power generation, distribution network, battery energy storage system and charging piles; the energy management subsystem charges the battery during low power consumption and stores excess electric energy according to the peak and valley characteristics of power supply, and feeds energy back to the AC bus to supply power to the DC charging pile or other loads during peak power consumption, thereby smoothing the volatility of the pressure energy generator.

[0012] Furthermore, the energy consumption subsystem includes electrical equipment for voltage regulating station process, life, etc., new energy charging piles, variable power resistor cabinets and fixed power resistor cabinets; the electrical equipment, the new energy charging piles and the variable power resistor cabinet are in parallel; the fixed power resistor cabinet is directly connected to the generator through the AC contactor.

[0013] Furthermore, the power-consuming equipment and the new energy charging pile are normal energy-consuming equipment; the variable power resistor cabinet and the fixed power resistor cabinet are emergency power-consuming equipment. The power-consuming equipment is a normal load with a power of 5kW, which is lower than the power generation power of the power generation subsystem; the new energy charging pile is an intermittent power-consuming equipment with a power of 60kW, which can provide charging services for two new energy vehicles at the same time; the variable power resistor cabinet is an emergency load with an adjustable power range of 0 to 20kW, and its actual load can be automatically adjusted according to the load changes at the power generation end and the power consumption end of the system to meet the full load absorption of the power generation end; the fixed power resistor cabinet is an emergency load with a power of 20kW, which is the same as the output power of the generator.

[0014] The power loads in this system include process and life normal loads in the voltage regulating station, charging equipment (electric vehicle charging piles and electric vehicle charging piles, dynamic loads), energy storage batteries (balanced loads) and load resistor cabinets (emergency loads). In order to ensure that the power generation load matches the total load of "normal load + dynamic load + balanced and emergency load", the power consumption between each power-consuming equipment and the charging and discharging mode of the energy storage battery need to be logically controlled by the set PLC controller.

[0015] The system operation strategy of the present invention:

[0016] 1. When the total load of power equipment (normal load + dynamic load) is lower than the power generation load, the power system in the station is disconnected from the city grid, and all power equipment is supplied by the pressure energy power generation system. The excess power is converted into direct current through the rectifier and input into the energy storage battery for storage. The peak is cut by charging the energy storage battery group, and the system reaches a balance. That is:

[0017] Production = Use (normal load + dynamic load) + Storage (balanced load) (1)

[0018] 2. When the energy storage battery pack is full or there is surplus power generation load, that is, when there is an imbalance between production, storage and use, the excess power will be released through the variable power resistor cabinet, and the resistor cabinet will release the power to cut the peak in an emergency, so as to achieve system balance.

[0019] Production = Use (normal load + dynamic load) + storage (balanced load) + emergency load (2)

[0020] 3. In extreme cases, when "normal load + dynamic load + energy storage battery pack" are all without load, in order to ensure the system load balance, the pressure energy generating electronic system runs smoothly, and the power generation load is all consumed by the load resistor cabinet, that is,

[0021] Production = Emergency Load (3)

[0022] 4. When the total load of the electrical equipment (normal load + dynamic load) is higher than the load that the pressure energy power generation equipment can provide, the PLC controller sends a command to the energy storage battery, and the stored energy is converted into AC power by the inverter and then output to supply power to the electrical equipment; the system reaches balance by releasing the stored energy to fill the valley. That is:

[0023] Production + Storage = Use (4)

[0024] 5. If there is still a shortfall after the energy storage battery pack releases electricity, it can be connected to the city grid to supplement the electricity, thus filling the valley of load and meeting the dynamic load and normal load requirements. That is:

[0025] Production + City electricity = Use (5)

[0026] The basic principles for ensuring the system load of the present invention are:

[0027] 1. Make every effort to ensure the stable operation of the pressure energy generating device, reduce fluctuations, reduce the fluctuation range, and strive to maintain the power generation load between 70% and 95% of the rated power;

[0028] 2. Avoid frequent start and stop of the pressure energy generating electronic system to maintain high efficiency of the power generation system;

[0029] 3. Release the energy stored in the energy storage battery in time. Under normal circumstances, the energy storage battery group is in a lower energy storage position;

[0030] 4. Try to avoid the operation of the variable power emergency resistor cabinet, or make it operate at low load to ensure the effective use of electric energy;

[0031] 5. Ensure that the power generation load is less than or equal to the aforementioned total load (grid-connected but not connected to the grid);

[0032] 6. When necessary, adjust the pressure to ensure that the power generation load has reached a balance between production, storage and use.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] 1. The present invention does not consume natural gas, but uses the pressure energy released by pipeline natural gas pressure regulation to drive the rotor expander to generate power, drive the generator to generate electricity, fully recycles and utilizes the pressure energy released by pressure regulation, avoids its waste, and saves energy and reduces emissions.

[0035] 2. The present invention utilizes storage and discharge equipment such as energy storage batteries and variable power resistor cabinets, as well as the introduction of city power and the adjustment of pressure energy power generation load to achieve real-time balance between power generation load and power loads such as charging piles and voltage regulating stations. That is, on the basis of pressure energy power generation to meet the conventional power consumption of the voltage regulating station, energy storage batteries are used to store excess power during low power consumption, and during the peak charging period, energy storage batteries and city power are used together to supply power to new energy charging piles to meet peak power demand, which not only achieves peak shaving and valley filling, but also saves the problem of power distribution and capacity expansion. It is a sustainable energy utilization method with very large social and economic benefits.

[0036] 3. The present invention utilizes the electric energy generated by the generator to provide energy for the heat exchanger, and performs heat exchange with the natural gas at the outlet of the rotor expander, so that the natural gas entering the main road meets the temperature requirements of town gas.

[0037] 4. The present invention is based on the pressure energy recovery power generation during the pressure reduction process of high-pressure natural gas in urban gas pressure regulating stations, and combines energy storage batteries with new energy charging piles. Through the energy management system, it realizes multiple modes such as round-robin charging and intelligent dynamic allocation charging, supports intelligent scheduling of electric energy, and can adjust the charging strategies of charging piles and energy storage batteries in real time according to load fluctuations at the power consumption end, thereby ensuring full utilization of pressure energy power generation, reliability of city power replenishment, and economy of charging, reducing operating costs and improving system operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 An overall schematic diagram of the present invention. DETAILED DESCRIPTION

[0040] The present invention is further analyzed below in conjunction with specific embodiments. Obviously, what is described is only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Example

[0042] A production, storage and utilization integrated comprehensive utilization system based on pressure energy power generation, the system comprises an existing natural gas system, a power generation subsystem based on a dual-rotor expander, an energy storage subsystem, an energy use subsystem and an energy management subsystem for intelligently managing the power consumption of the energy use subsystem and the power storage sequence of the energy storage subsystem; the existing natural gas system comprises a high-pressure gas transmission pipeline, an existing pressure regulating system and a medium-pressure urban pipe network connected in sequence; the power generation subsystem comprises a dual-rotor expander and a generator connected thereto; a branch is led out on the inlet pipeline of the existing pressure regulating system, the dual-rotor expander is connected to the branch, and the natural gas of the drainage part led out through the branch is reduced in pressure by the dual-rotor expander and regulated by the pressure regulator, and then connected to the outlet of the existing pressure regulating system and merged into the medium-pressure urban pipe network, and at the same time, the pressure released by the natural gas pressure reduction can drive the dual-rotor expander to generate power, thereby driving the generator to generate electricity; the generator, the energy storage subsystem and the energy use subsystem share an AC bus;

[0043] The flow rate of the existing pressure regulating system is 8000~10000Nm 3 / h, inlet pressure 3.7MPa, inlet temperature 15℃, outlet pressure 0.35MPa. And because the flow rate in the pressure regulating station fluctuates due to the uneven downstream gas consumption during the pressure regulation process, the natural gas inlet flow rate of the branch where the dual-rotor expander is located is adjusted to 2500Nm 3 / h, which is less than the minimum gas flow rate of the pressure regulating station, to ensure that the expander can work stably and output electricity continuously and stably. At the same time, the inlet pressure of the natural gas in the branch is 1.8MPa and the inlet temperature is 15℃. After the dual-rotor expander works to reduce the pressure, the outlet pressure is 0.73MPa and the outlet temperature is -29℃.

[0044] The energy storage subsystem includes a rectifier, an energy storage battery and an inverter connected in sequence; the rectifier rectifies the AC power output by the generator set into DC power and stores it in the energy storage battery; the inverter converts the DC power output by the rectifier or the energy storage battery into AC power with stable voltage and frequency, and then outputs it to the energy-using subsystem. Among them, the rectifier power is 20kW; the energy storage battery is composed of a group of 100kWh battery stacks with a rated total capacity of 108.8kWh, using 680 50Ah lithium batteries, 680×3.2×50=108.8kWh; the energy storage system conversion efficiency is about 92%, and the actual power of the system is 108.8kWh×0.92=100kWh; the inverter power is 100kW.

[0045] The energy storage subsystem is connected to the energy management subsystem through an AC bus; the energy management subsystem includes a connected AC contactor, a PLC controller, an energy management system and a current detection device; the energy management subsystem dynamically controls the output power of the inverter through an intelligent control strategy according to the load conditions, and intelligently dispatches the power between pipeline natural gas pressure energy generation, distribution network, battery energy storage system and charging piles; the energy management subsystem charges the battery and stores excess electric energy during low power consumption according to the peak and valley characteristics of power supply, and feeds energy back to the AC bus to supply power to DC charging piles or other loads during peak power consumption, which can smooth the volatility of the pressure energy generator. Among them, the energy consumption subsystem includes power consumption equipment for voltage regulation station field process, life, etc., new energy charging piles, variable power resistor cabinets and fixed power resistor cabinets; the power consumption equipment, the new energy charging piles and the variable power resistor cabinet are in parallel relationship; the fixed power resistor cabinet is directly connected to the generator through the AC contactor. Furthermore, the power-consuming equipment and the new energy charging pile are normal energy-consuming equipment; the variable power resistor cabinet and the fixed power resistor cabinet are emergency power-consuming equipment. The power-consuming equipment is a normal load with a power of 5kW, which is lower than the power generation power of the power generation subsystem; the new energy charging pile is an intermittent power-consuming equipment with a power of 60kW, which can provide charging services for two new energy vehicles at the same time; the variable power resistor cabinet is an emergency load with an adjustable power range of 0 to 20kW, and its actual load can be automatically adjusted according to the load changes at the power generation end and the power consumption end of the system to meet the full load absorption of the power generation end; the fixed power resistor cabinet is an emergency load with a power of 20kW, which is the same as the output power of the generator.

[0046] The power loads in this system include process and life normal loads in the voltage regulating station, charging equipment (electric vehicle charging piles and electric vehicle charging piles, dynamic loads), energy storage batteries (balanced loads) and load resistor cabinets (emergency loads). In order to ensure that the power generation load matches the total load of "normal load + dynamic load + balanced and emergency load", the power consumption between each power-consuming equipment and the charging and discharging mode of the energy storage battery need to be logically controlled by the set PLC controller.

[0047] The system operation strategy of the present invention:

[0048] 1. When the total load of power equipment (normal load + dynamic load) is lower than the power generation load, the power system in the station is disconnected from the city grid, and all power equipment is supplied by the pressure energy power generation system. The excess power is converted into direct current through the rectifier and input into the energy storage battery for storage. The peak is cut by charging the energy storage battery group, and the system reaches a balance. That is:

[0049] Production = Use (normal load + dynamic load) + Storage (balanced load) (1)

[0050] 2. When the energy storage battery pack is full or there is surplus power generation load, that is, when there is an imbalance between production, storage and use, the excess power will be released through the variable power resistor cabinet, and the resistor cabinet will release the power to cut the peak in an emergency, so as to achieve system balance.

[0051] Production = Use (normal load + dynamic load) + storage (balanced load) + emergency load (2)

[0052] 3. In extreme cases, when "normal load + dynamic load + energy storage battery pack" are all without load, in order to ensure the system load balance, the pressure energy generating electronic system runs smoothly, and the power generation load is all consumed by the load resistor cabinet, that is,

[0053] Production = Emergency Load (3)

[0054] 4. When the total load of the electrical equipment (normal load + dynamic load) is higher than the load that the pressure energy power generation equipment can provide, the PLC controller sends a command to the energy storage battery, and the stored energy is converted into AC power by the inverter and then output to supply power to the electrical equipment; the system reaches balance by releasing the stored energy to fill the valley. That is:

[0055] Production + Storage = Use (4)

[0056] 5. If there is still a shortfall after the energy storage battery pack releases electricity, it can be connected to the city grid to supplement the electricity, thus filling the valley of load and meeting the dynamic load and normal load requirements. That is:

[0057] Production + City electricity = Use (5)

[0058] The basic principles for ensuring the system load of the present invention are:

[0059] 1. Make every effort to ensure the stable operation of the pressure energy generating device, reduce fluctuations, reduce the fluctuation range, and strive to maintain the power generation load between 70% and 95% of the rated power;

[0060] 2. Avoid frequent start and stop of the pressure energy generating electronic system to maintain high efficiency of the power generation system;

[0061] 3. Release the energy stored in the energy storage battery in time. Under normal circumstances, the energy storage battery group is in a lower energy storage position;

[0062] 4. Try to avoid the operation of the variable power emergency resistor cabinet, or make it operate at low load to ensure the effective use of electric energy;

[0063] 5. Ensure that the power generation load is less than or equal to the aforementioned total load (grid-connected but not connected to the grid);

[0064] 6. When necessary, adjust the pressure to ensure that the power generation load has reached a balance between production, storage and use.

[0065] The working principle or process of the present invention:

[0066] 3.7MPa natural gas (flow rate 8000~10000Nm 3 / h) is introduced into the pressure regulating station through the pipeline, and then enters the city's medium-pressure transmission and distribution pipeline network after being reduced to 0.35MPa by the high-medium pressure regulator of the main road. A bypass pipe (i.e., the lead-out branch) is opened on the main road to introduce the high-pressure natural gas into the twin-rotor expander. As the natural gas expands and reduces pressure, its volume increases and performs external work, driving the generator to convert mechanical energy into electrical energy.

[0067] After the system is running, the power of the pressure energy generation electronic system is 20kW, the output voltage is 380V, the frequency is 50Hz, the AC contactor is closed to K2, and the energy management system performs intelligent scheduling of system power through signal detection and logical judgment, and controls the charging and discharging of the energy storage battery and current inversion, so as to realize the following energy consumption / energy storage sequence of pressure energy generation: 1. Process and routine electrical equipment in the voltage regulating station; 2. New energy charging piles; 3. Energy storage batteries; 4. Variable power resistor cabinet; 5. Fixed power resistor cabinet. At the same time, the energy management system monitors the current at the generator end and the load end. When the power at the generator end is higher than the power at the load end and the charging state of the energy storage battery is 100, the energy management system sends a command to the energy storage system to stop the charging circuit, and the PLC controller controls the load resistor cabinet group to be put into operation (the power adjustable range is 0~20kW) to consume the surplus power generated by the rotor expander using pressure energy; when the output power at the generator end is lower than the power demand at the load end, the PLC controller disconnects the load resistor cabinet and closes the grid-connected switch, and the mains network is connected to the system for power replenishment. The power required by the load end (station equipment, new energy charging pile) is provided by the generator and the mains network.

[0068] The output power of the pressure energy generator is AC power, which is converted into DC power by a 20kW rectifier and then divided into two paths. One path is connected to a 100kWh energy storage battery. The energy management system transmits the battery information to the energy storage inverter. The energy storage inverter discharges the battery according to the instructions and accepts the instructions issued by the energy management system to realize charging and discharging control. The other path is converted into 220V, 50Hz AC power by a 100kW inverter and supplies power to energy-consuming equipment.

[0069] The pressure energy generator set operates normally. The detection device detects that the current of this system flows to the mains network. The energy management system disconnects this system from the mains network through the PLC controller. This system operates in an isolated network. Generator power generation load supply station equipment, new energy charging piles, and energy storage battery stacks are used.

[0070] The operating condition of the power generator set is stable, with a power generation load of 20kW. On the basis of meeting the normal power load of 4kW for station equipment, there is still 16kW of surplus power. When the detection device detects that there is excess power uploaded to the mains power grid, the grid-connected switch is tripped, and the system is now off-grid. When the system power load is only the station power equipment, the energy management system controls the charging of the energy storage battery to ensure the storage of the output power of the generator set during the low power consumption period; when the intermittent power load-new energy charging pile is put into operation, the generator supplies power to the charging pile, and the energy management system controls the discharge of the energy storage battery to jointly supply power to the charging pile, while improving the charging efficiency of the charging pile, ensuring that the storage capacity of the energy storage battery is maintained at a low level, so that more surplus power load of the generator set can be stored when the charging pile is idle.

[0071] When the new energy charging pile is running at high load, due to the slow discharge of the energy storage battery or the charging state of the energy storage battery is 0, the energy management system controls the mains network to be connected to this system, and the mains power and the pressure energy generator set jointly supply power to the power load, ensuring that the charging efficiency of the new energy charging pile is not affected during peak power consumption.

[0072] When the new energy charging pile has no load and the energy storage battery is fully loaded, or the energy storage system or distribution system fails, the energy management system detects excess power, and the PLC controller controls the AC contactor to close to K1. The generator power is all absorbed by the fixed power resistor box (power is 20kW), ensuring the continuous operation of the generator set. The natural gas pressure drop and flow rate flowing through this branch are stable, which does not affect the stable operation of the natural gas pressure regulating station.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features therein may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An integrated production, storage and utilization system based on pressure energy power generation, It is characterized in that The system comprises an existing natural gas system, a power generation subsystem based on a dual-rotor expander, an energy storage subsystem, an energy use subsystem and an energy management subsystem for intelligently managing the power consumption of the energy use subsystem and the power storage sequence of the energy storage subsystem; the existing natural gas system comprises a high-pressure gas transmission pipeline, an existing pressure regulating system and a medium-pressure urban pipe network connected in sequence; the power generation subsystem comprises a dual-rotor expander and a generator connected thereto; a branch is led out on the inlet pipeline of the existing pressure regulating system, the dual-rotor expander is connected to the branch, the natural gas of the drainage part led out through the branch is depressurized by the dual-rotor expander and regulated by the pressure regulator, and then connected to the outlet of the existing pressure regulating system and merged into the medium-pressure urban pipe network; at the same time, the pressure released by the depressurization of the natural gas can drive the dual-rotor expander to generate power, and then drive the generator to generate electricity; the generator, the energy storage subsystem and the energy use subsystem share an AC bus; the flow rate of the existing pressure regulating system is 8000-10000Nm 3 / h, inlet pressure 3.7MPa, inlet temperature 15℃, outlet pressure 0.35MPa; the natural gas flow rate of the branch is 2500Nm3 / h; the inlet pressure is 1.8MPa, the inlet temperature is 15℃, and after the dual-rotor expander does work and reduces the pressure, the outlet pressure is 0.73MPa, and the outlet temperature is -29℃; the energy storage subsystem includes a rectifier, an energy storage battery and an inverter connected in sequence; the rectifier rectifies the AC power output by the generator set into DC power and stores it in the energy storage battery; the inverter converts the DC power output by the rectifier or the energy storage battery into AC power with stable voltage and frequency, and then outputs it to the energy-using subsystem.

2. According to claim 1, the integrated production, storage and comprehensive utilization system based on pressure energy power generation, It is characterized in that The rectifier power is 20kW; the inverter power is 100kW.

3. According to claim 1 or 2, the integrated production and storage comprehensive utilization system based on pressure energy power generation, It is characterized in that The energy storage battery is composed of a group of 100kWh battery stacks.

4. The integrated production, storage and utilization system based on pressure energy power generation according to claim 1, It is characterized in that The energy storage subsystem is connected to the energy management subsystem via an AC bus; the energy management subsystem includes a connected AC contactor, a PLC controller, an energy management system and a current detection device.

5. The integrated production, storage and utilization system based on pressure energy power generation according to claim 4, It is characterized in that The energy-consuming subsystem includes electrical equipment for voltage regulating station processes, daily life, etc., new energy charging piles, variable power resistor cabinets and fixed power resistor cabinets; the electrical equipment, the new energy charging piles and the variable power resistor cabinet are connected in parallel; the fixed power resistor cabinet is directly connected to the generator through the AC contactor.

6. The integrated production, storage and utilization system based on pressure energy power generation according to claim 5, It is characterized in that The electrical equipment and the new energy charging pile are normal energy-consuming equipment; the variable power resistor cabinet and the fixed power resistor cabinet are emergency power-consuming equipment.

7. The integrated production, storage and utilization system based on pressure energy power generation according to claim 5 or 6, It is characterized in that The electrical equipment is a normal load with a power of 5kW, which is lower than the power generation power of the power generation subsystem; the new energy charging pile is an intermittent electrical equipment with a power of 60kW; the variable power resistor cabinet is an emergency load with an adjustable power range of 0 to 20kW, and its actual load can be automatically adjusted according to the load changes at the power generation and power consumption ends of the system; the fixed power resistor cabinet is an emergency load with a power of 20kW.

8. The integrated production, storage and utilization system based on pressure energy power generation according to claim 7, It is characterized in that The new energy charging pile can charge at least two new energy vehicles at the same time.

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