Quick response method and system for primary frequency modulation of compressed air energy storage system

Abstract

The invention relates to the technical field of compressed air energy storage, in particular to a primary frequency modulation quick response method and system of a compressed air energy storage system. Comprising a compressed air main storage area and a compressed air frequency modulation storage area, and a check valve is arranged between the two areas, so that compressed air can only flow from the main storage area to the frequency modulation storage area. An outlet of the main gas storage area is connected with a gas inlet control valve through a pipeline, and the gas inlet control valve is connected with a multi-stage expansion machine through a pipeline; and an outlet pipeline of the frequency modulation valve is connected to the rear end of the air inlet control valve. In the operation process, the opening degree of the frequency modulation valve is dynamically adjusted according to changes of the opening degree of the air inlet control valve and the air storage pressure, the compressed air energy storage unit responds to the adjustment requirement of primary frequency modulation, high-pressure compressed air in a compressed air frequency modulation and air storage area enters the adjusting valve by opening the frequency modulation valve, and the air inlet pressure of the compressed air energy storage unit is increased; the power capability of compressed air energy storage is improved, and the purpose of quickly responding to primary frequency modulation is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of compressed air energy storage, and in particular to a primary frequency modulation rapid response method and system for a compressed air energy storage system. Background Art

[0002] In recent years, my country has developed rapidly in compressed air energy storage power stations, with increasingly larger installed capacity, and more and more obvious support and regulation of the power grid. With the increase in the capacity of compressed air energy storage units, the proportion of its load in the power grid increases when the unit is running, and the output of the unit is becoming more and more important to the stable operation of the power grid. At present, the capacity of compressed air energy storage units has exceeded 300MW, and its role in the power grid is equivalent to that of a 300MW thermal power generating unit. Therefore, the participation of compressed air energy storage units in primary frequency regulation is an inevitable measure to ensure the safe and stable operation of the power grid.

[0003] At present, compressed air energy storage units participate in primary frequency regulation mainly in two ways: one is to adjust the opening of the intake valve. This method has no problem when primary frequency regulation is needed to reduce the load, but as the compressed air pressure decreases, the intake valve gradually opens completely. When primary frequency regulation is needed to increase the load, the unit has no adjustment ability because the intake valve is fully opened, resulting in failure to meet the grid's demand for primary frequency regulation of the unit. Another way is to add an air supply valve. This method introduces compressed air from the front of the intake valve into the expander to increase the air intake of the subsequent stages of the expander. However, the newly introduced compressed air will displace the gas that has done part of the work in the expander, and the newly introduced compressed air will do less work in the expander, resulting in reduced efficiency.

[0004] Therefore, it is necessary to provide a primary frequency regulation system that is both efficient and meets the primary frequency regulation needs of the power grid in response to the above situation, so as to enhance the supporting role of compressed air energy storage to the power grid. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the problem to be solved by the present invention is the insufficient regulation ability of the compressed air energy storage unit in response to the primary frequency modulation of the power grid during operation, while improving the conversion efficiency of the compressed air energy storage unit to achieve the purpose of ensuring the safe and stable operation of the power grid.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, an embodiment of the present invention provides a primary frequency modulation rapid response method for a compressed air energy storage system, which comprises acquiring operating parameter data of a compressed air energy storage unit, and preprocessing the operating parameter data;

[0009] Preset a compressed air energy storage primary frequency modulation response model, and input the preprocessed operating parameter data into the response model;

[0010] A frequency modulation response control is performed according to the output of the response model.

[0011] As a preferred solution of the primary frequency modulation fast response method of the compressed air energy storage system of the present invention, wherein: the compressed air energy storage unit comprises:

[0012] A compressed air main gas storage area and a compressed air frequency modulation gas storage area, wherein a check valve is provided between the compressed air main gas storage area and the compressed air frequency modulation gas storage area;

[0013] The outlet of the compressed air main storage area is connected to the air intake control valve through a pipeline, and the air intake control valve is connected to the multi-stage expander through a pipeline;

[0014] The outlet of the compressed air frequency modulation gas storage area is connected to the frequency modulation valve through a pipeline, and the outlet pipeline of the frequency modulation valve is connected to the rear end of the air intake control valve.

[0015] As a preferred solution of the primary frequency modulation rapid response method of the compressed air energy storage system described in the present invention, the compressed air main storage area and the compressed air frequency modulation storage area can be one of a gas storage tank, a salt cavern or an artificial chamber.

[0016] As a preferred solution of the primary frequency modulation rapid response method of the compressed air energy storage system described in the present invention, the operating parameter data includes: intake control valve opening data, air storage area pressure data, frequency modulation valve opening data and unit load data; the frequency modulation valve adopts pneumatic, hydraulic or electric driving mode.

[0017] As a preferred solution of the primary frequency modulation rapid response method of the compressed air energy storage system described in the present invention, the preset compressed air energy storage primary frequency modulation response model includes: an input layer receives operating parameter data, a hidden layer performs data processing and analysis, and an output layer gives control instructions for the frequency modulation valve and the air intake control valve; the input parameters of the model include gas storage pressure, gas storage minimum drop pressure, air enthalpy value and frequency modulation power.

[0018] As a preferred scheme of the primary frequency modulation fast response method of the compressed air energy storage system described in the present invention, wherein: the volume of the compressed air frequency modulation gas storage area is determined by the following parameters: gas storage pressure, minimum gas storage drop pressure, air enthalpy value and frequency modulation power; the flow area of ​​the intake valve is determined by the minimum gas storage drop pressure, the unit capacity and the air enthalpy value.

[0019] As a preferred solution of the primary frequency modulation fast response method of the compressed air energy storage system of the present invention, wherein:

[0020] The primary frequency regulation response control includes: when the compressed air energy storage unit is just started, the air intake control valve controls the unit load to meet the primary frequency regulation upward regulation demand; during the operation of the compressed air energy storage unit, according to the changes in the air intake control valve opening and the pressure in the air storage area, the frequency regulation valve opening is dynamically adjusted to meet the primary frequency regulation upward regulation demand.

[0021] In a second aspect, an embodiment of the present invention provides a primary frequency modulation rapid response system for a compressed air energy storage system, which includes a parameter acquisition module for acquiring operating parameter data of a compressed air energy storage unit and performing preprocessing;

[0022] A model operation module is used to preset a compressed air energy storage primary frequency modulation response model and input the preprocessed operation parameter data into the response model;

[0023] The control execution module performs a frequency modulation response control according to the output of the response model.

[0024] In a third aspect, an embodiment of the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the primary frequency modulation rapid response method of the compressed air energy storage system as described in the first aspect of the present invention are implemented.

[0025] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the primary frequency modulation rapid response method of the compressed air energy storage system as described in the first aspect of the present invention are implemented.

[0026] The beneficial effects of the present invention are as follows: the present invention realizes physical isolation of the main gas storage area and the frequency modulation gas storage area by setting up independent compressed air main gas storage area and frequency modulation gas storage area, and setting up a check valve structural design between the two areas, avoiding gas backflow during the frequency modulation process, and ensuring the stability of the frequency modulation gas source. Combined with the arrangement of setting a special frequency modulation valve at the outlet of the frequency modulation gas storage area and connecting its outlet to the rear end of the intake control valve, a dual-path gas source supply regulation mechanism is formed, overcoming the problem of insufficient regulation capacity caused by traditional single intake control.

[0027] By adopting a step-by-step adjustment strategy, that is, the intake control valve is dominant in the startup phase, and the frequency modulation valve control scheme is dynamically adjusted according to the pressure change in the operation phase, a complete frequency modulation response chain is constructed. This control method avoids the problem of reduced efficiency caused by less work done by compressed air in the expander in the traditional air supply method, and realizes efficient utilization of the gas source. At the same time, through the optimization design of the volume of the frequency modulation gas storage area and the flow area of ​​the intake valve, the adequacy of the gas source and the stability of the regulation during the frequency modulation process are guaranteed, and finally the overall efficiency of the system and the frequency modulation support capacity of the power grid are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0029] Figure 1 A flow chart of a primary frequency modulation fast response method for a compressed air energy storage system;

[0030] Figure 2 A computer equipment diagram for a primary frequency modulation fast response method for a compressed air energy storage system;

[0031] Figure 3 A diagram of an air storage tank system for a primary frequency modulation fast response method of a compressed air energy storage system;

[0032] Figure 4 A diagram of a salt cavern system for a fast response method of primary frequency modulation for a compressed air energy storage system;

[0033] Figure 5 A control method logic diagram of a primary frequency modulation fast response method for a compressed air energy storage system;

[0034] Figure 6 This is the adjustment range diagram of the intake valve and frequency modulation valve for the primary frequency modulation fast response method of the compressed air energy storage system. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0038] Example 1

[0039] Reference Figure 1-2 , which is the first embodiment of the present invention, and provides a primary frequency modulation fast response method of a compressed air energy storage system, comprising:

[0040] S100: Acquire operating parameter data of the compressed air energy storage unit and pre-process the operating parameter data;

[0041] Specifically, the operating parameter data include: pressure data, valve opening data, unit load data and frequency modulation response data. The pressure data mainly includes the real-time pressure values ​​of the main gas storage area and the frequency modulation gas storage area; the valve opening data includes the real-time opening status of the air intake control valve and the frequency modulation valve; the unit load data includes the real-time load rate, maximum load and adjustable load range; the frequency modulation response data includes parameters such as frequency modulation response time and frequency modulation accuracy.

[0042] In an optional embodiment, the pressure data, valve opening data, unit load data and frequency modulation response data may be any combination of data obtained through the pressure sensor system, valve control system, unit monitoring system and frequency modulation response system. For example, when the pressure data is the real-time pressure value of the gas storage area, the frequency modulation response data may be the response time data.

[0043] In an optional embodiment, pressure data, valve opening data, unit load data and frequency modulation response data can also increase or decrease other operating data according to different target effects. For example, when more refined frequency modulation control is required, equipment vibration data (i.e., the fifth type of equipment data) can be added to capture the characteristics of the equipment operating status, thereby further improving the accuracy and comprehensiveness of the frequency modulation. In addition, considering the impact of the complexity of the operating scenario on the data quality, an adaptive data filtering algorithm can also be introduced to dynamically filter the collected operating data to ensure that high-quality control data can be obtained in various operating scenarios.

[0044] In an optional embodiment, if the frequency modulation response data is not needed, such data can be omitted, thereby reducing the workload of data collection and processing. However, in this application, in order to ensure the comprehensiveness of the frequency modulation control, such data is still retained.

[0045] It should be noted that the acquisition of the above-mentioned operating data can fully cover all aspects of the compressed air energy storage system, including but not limited to the gas storage system, valve system, expander system, generator system, etc., so as to ensure the accuracy and comprehensiveness of the control results. At the same time, by introducing multiple monitoring systems and data sources, such as pressure monitoring systems, valve monitoring systems, unit monitoring systems and frequency modulation monitoring systems, the advantages of various types of data can be fully utilized, complement each other, and improve the efficiency and accuracy of frequency modulation control. In addition, according to the needs of different target effects, the type and quantity of data can be flexibly adjusted to meet the needs of actual control work. This multi-source data fusion strategy not only improves the flexibility and adaptability of the control system, but also provides a rich data source for subsequent intelligent analysis.

[0046] Specifically, the intake control valve opening data may include valve position information, opening percentage, flow coefficient and other data; the gas storage area pressure data may include real-time pressure value collected by the pressure sensor, corrected pressure after temperature compensation and other data; the frequency modulation valve opening data may include valve opening angle, flow area and other data; the unit load data may include generator output power, speed and other data.

[0047] In an optional embodiment, the operating parameter data can be collected and acquired in real time through an automated control system such as a DCS system (distributed control system), a PLC controller, a SCADA system, etc. For example, when a DCS system is used, basic data such as pressure, temperature, and flow can be collected through field instruments, and then the system performs data processing and calculation to obtain the required operating parameters.

[0048] In an optional embodiment, the collection frequency of the operating parameter data can be dynamically adjusted according to actual needs. For example, a lower sampling frequency (such as 1 time / second) can be used during the normal operation of the unit, and the sampling frequency can be increased (such as 10 times / second) during the frequency modulation response process to obtain more accurate process data. In addition, different sampling cycles can be set for different types of parameters, such as using a higher sampling frequency for valve opening data with high response speed requirements.

[0049] In an optional embodiment, preprocessing the collected operating parameter data may include: data validity check, outlier processing, data smoothing and filtering, etc. For example, median filtering may be used to remove mutation points, sliding average method may be used to smooth data, and outliers may be removed by setting reasonable upper and lower limits.

[0050] It should be noted that the collection and preprocessing of the above operating parameter data needs to ensure the real-time, accuracy and reliability of the data. By adopting high-precision sensors, reliable communication networks and advanced data processing algorithms, the accuracy of subsequent model analysis and control decisions can be ensured. At the same time, the system should also have data backup and fault diagnosis functions, and timely alarm and take countermeasures when data collection or transmission is abnormal.

[0051] In an embodiment of the present application, the compressed air energy storage unit includes a compressed air main gas storage area and a compressed air frequency modulation gas storage area, and a check valve is arranged between the compressed air main gas storage area and the compressed air frequency modulation gas storage area.

[0052] S101: Compressed air energy storage unit includes:

[0053] A main compressed air storage area and a frequency-modulated compressed air storage area, a check valve is provided between the main compressed air storage area and the frequency-modulated compressed air storage area;

[0054] The outlet of the compressed air main storage area is connected to the air intake control valve through a pipeline, and the air intake control valve is connected to the multi-stage expander through a pipeline;

[0055] The outlet of the compressed air frequency modulation gas storage area is connected to the frequency modulation valve through a pipeline, and the outlet pipeline of the frequency modulation valve is connected to the rear end of the air intake control valve.

[0056] S102: The compressed air main storage area and the compressed air frequency modulation storage area can be one of a gas storage tank, a salt cavern or an artificial chamber.

[0057] Specifically, the main compressed air storage area can use large gas tanks, underground salt caverns or artificial caverns, and the compressed air frequency modulation storage area can use small gas tanks or buffer tanks. The check valve can be of different types such as spring type, weight type or electronic control type to prevent the compressed air from flowing back from the frequency modulation storage area.

[0058] In an optional embodiment, the volume of the compressed air main storage area can be designed according to the rated power and continuous operation time requirements of the unit. For example, for a 300MW unit, if it is required to run continuously for 4 hours, the volume of the main storage area needs to be determined by considering factors such as gas storage pressure and air consumption rate. The volume of the frequency modulation gas storage area mainly depends on the frequency modulation power and response time requirements.

[0059] In an optional embodiment, the main gas storage area and the frequency modulation gas storage area can use different pressure levels. For example, the main gas storage area can use a higher storage pressure (such as 70-100 bar) to increase the energy storage density, while the frequency modulation gas storage area can use a relatively low pressure (such as 40-50 bar) to facilitate rapid response. The pressure difference between the two areas can be smoothly transitioned by a pressure regulating device.

[0060] It should be noted that the design of the gas storage system needs to comprehensively consider safety, economy, reliability and other aspects. The gas storage container should comply with the relevant pressure vessel standards and have necessary safety protection devices such as safety valves and vent valves. At the same time, the layout of the gas storage system should fully consider the pipeline pressure loss, minimize elbows and throttling components, and ensure the timeliness of the system response.

[0061] In an embodiment of the present application, the outlet of the compressed air main air storage area is connected to the air intake control valve through a pipeline, and the air intake control valve is connected to the multi-stage expander through a pipeline; the outlet of the compressed air frequency modulation air storage area is connected to the frequency modulation valve through a pipeline, and the frequency modulation valve outlet pipeline is connected to the rear end of the air intake control valve.

[0062] S103: The operating parameter data include: air intake control valve opening data, gas storage area pressure data, frequency modulation valve opening data and unit load data; the frequency modulation valve adopts pneumatic, hydraulic or electric driving mode.

[0063] Specifically, the intake control valve can be an electric regulating butterfly valve, ball valve or sleeve valve, and the frequency regulating valve can be a fast-response electro-hydraulic linkage valve. The pipeline system should use appropriate pipe diameters and materials, and consider insulation measures to reduce heat loss.

[0064] In an optional embodiment, the selection of the intake control valve and the frequency modulation valve needs to consider factors such as maximum flow rate, pressure level, regulation characteristics, response speed, etc. For example, the intake control valve can use a regulating valve with equal percentage characteristics to obtain better regulation performance, and the frequency modulation valve should use a valve with fast opening characteristics to improve the response speed.

[0065] In an optional embodiment, the valve drive device can use different actuators. For example, the air intake control valve can use an electric actuator with high adjustment accuracy; the frequency modulation valve can use an electro-hydraulic linkage actuator with the characteristic of fast response. The selection of the actuator needs to comprehensively consider the requirements of response time, control accuracy, reliability, etc.

[0066] It should be noted that the design of valves and piping systems should ensure smooth airflow and minimum pressure loss. The effects of thermal expansion and contraction should be considered when arranging the piping, and appropriate brackets and compensation devices should be set. At the same time, the system should also be equipped with necessary instruments such as pressure gauges, thermometers, etc. to monitor the operating status.

[0067] In an embodiment of the present application, the preset compressed air energy storage primary frequency modulation response model includes: an input layer receives operating parameter data, a hidden layer performs data processing and analysis, and an output layer gives control instructions for the frequency modulation valve and the intake control valve.

[0068] S200: Preset a compressed air energy storage primary frequency modulation response model, and input the preprocessed operating parameter data into the response model;

[0069] Specifically, the input layer includes parameters such as intake control valve opening, gas storage pressure, frequency modulation valve opening, unit load, etc.; the hidden layer adopts a multi-layer neural network structure and can include multiple hidden layer nodes; the output layer gives the adjustment amount of the valve opening.

[0070] In an optional embodiment, the model training process includes steps such as data preprocessing, model structure design, and parameter optimization. For example, historical operation data can be used for model training, and the network weights can be optimized through a back-propagation algorithm so that the control strategy output by the model can respond quickly and accurately to system disturbances.

[0071] In an optional embodiment, the evaluation indicators of the model include: response time, adjustment accuracy, stability, etc. For example, the performance of the model under different working conditions can be verified through simulation tests, including characteristic tests such as step response and frequency response. The model structure and parameters are optimized and adjusted according to the test results.

[0072] It should be noted that the design of the response model needs to fully consider the dynamic characteristics and constraints of the system. The model should have good generalization ability and be able to adapt to different operating conditions. At the same time, the real-time requirements of the model must also be considered to ensure that the calculation and decision-making are completed within the specified time.

[0073] S201: The preset compressed air energy storage primary frequency modulation response model includes: the input layer receives the operating parameter data, the hidden layer performs data processing and analysis, and the output layer gives the control instructions of the frequency modulation valve and the air intake control valve; the input parameters of the model include the gas storage pressure, the minimum gas storage drop pressure, the air enthalpy value and the frequency modulation power.

[0074] S202: The volume of the compressed air frequency modulation gas storage area is determined by the following parameters: gas storage pressure, minimum gas storage drop pressure, air enthalpy value and frequency modulation power; the flow area of ​​the air inlet valve is determined by the minimum gas storage drop pressure, unit capacity and air enthalpy value.

[0075] S300: Perform a frequency modulation response control according to the output of the response model.

[0076] S301: The primary frequency regulation response control includes: when the compressed air energy storage unit is just started, the air intake control valve controls the unit load to meet the primary frequency regulation increase demand; during the operation of the compressed air energy storage unit, according to the changes in the air intake control valve opening and the pressure in the air storage area, the frequency regulation valve opening is dynamically adjusted to meet the primary frequency regulation increase demand.

[0077] In the embodiment of the present application, the primary frequency modulation response control includes: the load is controlled by the air intake control valve during the unit startup phase, and the frequency modulation valve opening is dynamically adjusted according to the changes in the air intake control valve opening and the gas storage pressure during operation.

[0078] Specifically, the control strategy can be divided into two modes: normal regulation and fast response. Normal regulation is mainly achieved through the intake control valve, while fast response is mainly achieved through the frequency modulation valve. The system selects the appropriate control mode according to the size and change rate of the frequency deviation.

[0079] In an optional embodiment, the controller may use algorithms such as PID and fuzzy control. For example, for small frequency fluctuations, PID control may be used to achieve smooth regulation; for large disturbances, fuzzy control strategy may be used to quickly adjust the valve opening according to the frequency deviation and rate of change.

[0080] In an optional embodiment, the system can dynamically optimize control parameters based on real-time operating data. For example, by identifying system characteristics online, the controller parameters can be adaptively adjusted to improve control performance. At the same time, equipment characteristics and system constraints, such as valve opening limit, pressure change rate limit, etc., can be considered.

[0081] It should be noted that the design of the control system should ensure timely response and smooth regulation. By properly configuring the control strategy and parameters, it is necessary to meet the grid's requirements for primary frequency regulation and ensure the safe and stable operation of the equipment. At the same time, the system should also have self-diagnosis and fault handling functions, so that timely countermeasures can be taken when control is abnormal.

[0082] Furthermore, this embodiment also provides a primary frequency modulation fast response system of a compressed air energy storage system, comprising:

[0083] The parameter acquisition module acquires the operating parameter data of the compressed air energy storage unit and performs preprocessing;

[0084] The model operation module presets a compressed air energy storage primary frequency modulation response model and inputs the preprocessed operation parameter data into the response model;

[0085] The control execution module performs a frequency modulation response control according to the output of the response model.

[0086] In summary, by setting up independent compressed air main storage area and frequency modulation storage area, and setting a check valve between the two areas, physical isolation of the main storage area and the frequency modulation storage area is achieved. This design avoids gas backflow during the frequency modulation process, ensures the stability of the frequency modulation gas source, and ultimately achieves the effect of improving the reliability of the system frequency modulation.

[0087] By setting a dedicated frequency modulation valve at the outlet of the frequency modulation gas storage area and connecting its outlet to the rear end of the intake control valve, a dual-path gas supply adjustment mechanism is formed. This design overcomes the problem of insufficient adjustment capacity caused by traditional single intake control, realizes rapid gas source replenishment during the frequency modulation process, and ultimately achieves the effect of improving the system frequency modulation response speed.

[0088] By adopting a variety of optional frequency-modulating valve drive modes such as pneumatic, hydraulic or electric, a flexible actuator selection mechanism is established. This design adapts to the regulation needs under different working conditions, avoids the limitations of a single drive mode, and ultimately achieves the effect of improving system adaptability.

[0089] By designing a phased frequency modulation control strategy, that is, the air intake control valve is dominant in the startup phase, and the frequency modulation valve is dynamically adjusted according to pressure changes in the operation phase, a complete frequency modulation response chain is constructed. This control scheme overcomes the problem of reduced efficiency caused by air replenishment in traditional frequency modulation methods, realizes efficient use of air sources, and ultimately achieves the effect of improving the overall efficiency of the system.

[0090] Through the optimization design of the frequency modulation gas storage area volume and the intake valve flow area, an accurate calculation model based on parameters such as gas storage pressure, drop pressure, and air enthalpy was established. This design method ensures the sufficiency and stability of the gas source during the frequency modulation process, avoids the uncertainty of empirical design, and ultimately achieves the effect of improving system reliability.

[0091] By adopting a step-by-step adjustment strategy, that is, a control scheme that gradually increases the frequency modulation valve opening as the main gas storage pressure decreases, dynamic compensation of the frequency modulation capability is achieved. This control mode overcomes the problem of insufficient adjustment capability after the intake valve is fully opened in the traditional frequency modulation method, ensures the continuous frequency modulation capability of the system, and ultimately achieves the effect of improving the frequency modulation support capability of the power grid.

[0092] Compared with the two existing frequency modulation methods mentioned in the background technology, the present invention avoids the problem of insufficient regulation ability caused by relying solely on intake valve regulation and overcomes the problem of reduced efficiency caused by traditional air supply methods through the cooperation of an independent frequency modulation gas storage area and a dedicated frequency modulation valve. It ultimately achieves the unification of frequency modulation response speed and system efficiency, providing more reliable support for the stable operation of the power grid.

[0093] Example 2

[0094] Reference Figure 3 - Figure 6 , which is the second embodiment of the present invention, provides a method for rapid response of primary frequency modulation of a compressed air energy storage system. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0095] It includes the compressed air main storage area and the compressed air frequency modulation storage area. A check valve is installed between the compressed air main storage area and the compressed air frequency modulation storage area, and compressed air can only flow from the compressed air main storage area to the compressed air frequency modulation storage area. The outlet of the compressed air main storage area is connected to the air intake control valve through a pipeline, the air intake main control valve is connected to the multi-stage expander through a pipeline, and the multi-stage expander is connected to the generator through a transmission shaft.

[0096] The outlet of the compressed air frequency modulation gas storage area is connected to the frequency modulation valve through a pipeline. The outlet pipeline of the frequency modulation valve is connected to the air intake control valve and then connected to the multi-stage expander.

[0097] The main compressed air storage area here can be an air storage tank, a salt cavern, an artificial chamber, etc., and the compressed air frequency modulation storage area can be an air storage tank, a salt cavern, etc.

[0098] The frequency regulating valve can be driven by pneumatic, hydraulic, electric, etc. When the compressed air energy storage unit is just started, when the air intake control valve is in the actual valve position, the air intake control valve controls the unit load to meet the primary frequency regulation requirements.

[0099] At the initial startup stage of the compressed air energy storage unit, when the air intake control valve is in the actual valve position, the air intake control valve controls the unit load to meet the primary frequency regulation requirements. S0 is the maximum valve position that meets the maximum upper regulation capacity of the primary frequency regulation of the power grid.

[0100] When the compressed air energy storage unit operates normally, the following steps are included:

[0101] Step 1: When the compressed air energy storage unit is started, the opening of the air intake control valve is gradually increased until the compressed air energy storage unit runs at full load. At this time, the valve position is s=smin, s≤s0.

[0102] Step 2: The compressed air energy storage unit operates at full load. As the pressure in the gas storage area decreases, the opening of the intake control valve gradually increases. When the intake valve opening s>s0 and s<100%, the intake regulating valve and the frequency regulating valve increase their opening to meet the power required for the primary frequency regulation.

[0103] Step 3: The compressed air energy storage unit operates at full load. As the pressure in the gas storage area decreases, the opening of the intake control valve gradually increases. When the intake valve opening s=100%, that is, the intake control valve is fully open, the frequency modulation valve increases the opening to meet the power required for the primary frequency modulation.

[0104] Step 4: As the pressure in the gas storage area decreases, the load capacity of the compressed air energy storage unit decreases, and the valve position opening s of its intake valve is 100%. The frequency regulating valve increases the opening to meet the power required for the primary frequency regulation.

[0105] The volume Vt of the air frequency modulation storage area is calculated as follows:

[0106]

[0107] Where V t is the volume of the air frequency modulation storage area, p max is the gas storage pressure, p min is the minimum gas storage pressure, hair is the air enthalpy after heat exchange, and E is the total power of the primary frequency regulation during the compressed air energy storage operation cycle.

[0108] The flow area of ​​the frequency modulation valve should be able to meet the requirements of the maximum frequency modulation action at the lowest pressure.

[0109] Under the action of the check valve, in the energy storage stage, when the pressure in the compressed air main storage area is higher than that in the compressed air frequency modulation storage area, the compressed air flows from the compressed air main storage area into the compressed air frequency modulation storage area; in the power generation stage, since the pressure in the compressed air frequency modulation storage area drops slowly, the check valve prevents the compressed air from flowing from the compressed air frequency modulation storage area into the compressed air main storage area.

[0110] The invention comprises a compressed air storage tank 1, an emergency discharge pipe 4, a heat exchanger 5, a multi-stage expander 6 connected in series and a generator 7. An intake electric main valve 2 and an intake regulating valve 3 are sequentially installed on the outlet main pipe of the compressed air storage tank 1. The intake regulating valve 3 is connected to the multi-stage expander 6. Heat exchangers 5 are installed on the intake pipes of each stage of the multi-stage expander 6. An emergency discharge pipe 4 is installed on the intake main pipe in front of each heat exchanger 5. A discharge valve 8 is installed on the emergency discharge pipe 4. The generator 7 is connected to the transmission shaft of at least one stage of the expander 6.

[0111] Compressed air main storage area 30, compressed air frequency modulation storage area 25, air intake control valve 16, frequency modulation valve 26, check valve 27, multi-stage expander 13, generator 15, compressor 2, heat storage tank 11, cold storage tank 5, heat exchanger 7 and corresponding valve pipeline system.

[0112] Preferably, the diameter of the emergency discharge pipe 4 is 80% greater than the diameter of the air intake main pipe.

[0113] Preferably, the discharge valve 4 is electrically connected to the remote control terminal using a solenoid valve, and the emergency discharge valve uses a hydraulic or pneumatic servo system with an opening time of less than 1 second, which can achieve remote control.

[0114] Preferably, the interface between the emergency discharge pipe 4 and the air intake main pipe is at the highest horizontal position of the main pipeline.

[0115] When the system is working, high-pressure air is stored in the air storage tank 1, and the outlet flow is regulated by the air intake electric main valve 2 and the air intake regulating valve 3, and enters the multi-stage heat exchanger 5 for heat exchange. The high-pressure air after heat exchange enters the multi-stage expander 6 for expansion, driving the generator 7 to generate electricity.

[0116] A discharge method of a kinetic energy recovery system and method for an expansion generator set. When the generator outlet switch disconnect signal and the intake electric main air valve closing signal are met at the same time, or when it is manually opened, the emergency discharge valve opens; when it is manually closed, or when the generator speed reaches zero and the intake electric main air valve is closed at the same time, the emergency discharge valve closes.

[0117] When the power generation process encounters a load shedding condition, the generator outlet switch will trip. Due to the hysteresis characteristics of the transmission signal and the control system, the intake valve will begin to close after a certain delay time t1, and will not be completely closed and cut off the intake until after its own closing time t2, so that the rotational inertia of the unit's load shedding acts on the rotor shared by the expander and the generator, causing the speed of the expander and the generator to increase. Due to the delay in closing the intake valve, the residual pressurized gas in the expander, heat exchanger and pipeline will continue to act on the rotor, causing the speed to further increase. At this time, the emergency exhaust valve can be opened to discharge the residual pressurized gas in the system to ensure the safe operation of the unit.

[0118] The present invention eliminates the influence of the delay in closing the intake valve when the power generation process is load shedding. Due to the delay in closing the intake valve, the residual pressurized gas in the expander, the heat exchanger and the pipeline will continue to act on the rotor, causing the rotation speed to further increase, which may easily cause an overspeed accident of the unit. The present invention effectively solves the problem of further increase in the rotation speed of the rotor due to the delay in closing the intake valve during the load shedding process of the unit, and can discharge the residual pressurized gas in the system to ensure the safe operation of the unit.

[0119] Example 3

[0120] This embodiment also provides a computer device, which is applicable to a method for rapid response of primary frequency modulation of a compressed air energy storage system, and includes a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement a forced oscillation detection and positioning method for a distribution network as proposed in the above embodiment.

[0121] This embodiment further provides a storage medium on which a computer program is stored. When the program is executed by a processor, a forced oscillation detection and positioning method for a distribution network is implemented as proposed in the above embodiment.

[0122] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0123] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0124] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0125] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering, or processing in another suitable manner as necessary, and then stored in a computer memory.

[0126] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0127] It should be noted that 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A primary frequency modulation rapid response method for a compressed air energy storage system, characterized in that: The method comprises obtaining operating parameter data of the compressed air energy storage unit and preprocessing the operating parameter data; Preset a compressed air energy storage primary frequency modulation response model, and input the preprocessed operating parameter data into the response model; A frequency modulation response control is performed according to the output of the response model.

2. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 1, characterized in that: The compressed air energy storage unit comprises: A compressed air main gas storage area and a compressed air frequency modulation gas storage area, wherein a check valve is provided between the compressed air main gas storage area and the compressed air frequency modulation gas storage area; The outlet of the compressed air main storage area is connected to the air intake control valve through a pipeline, and the air intake control valve is connected to the multi-stage expander through a pipeline; The outlet of the compressed air frequency modulation gas storage area is connected to the frequency modulation valve through a pipeline, and the outlet pipeline of the frequency modulation valve is connected to the rear end of the air intake control valve.

3. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 2, characterized in that: The compressed air main storage area and the compressed air frequency modulation storage area can be one of a gas storage tank, a salt cavern or an artificial chamber.

4. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 3, characterized in that: The operating parameter data include: intake control valve opening data, gas storage area pressure data, frequency modulation valve opening data and unit load data; the frequency modulation valve adopts pneumatic, hydraulic or electric driving mode.

5. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 4, characterized in that: The preset compressed air energy storage primary frequency modulation response model includes: an input layer receives operating parameter data, a hidden layer performs data processing and analysis, and an output layer gives control instructions for a frequency modulation valve and an air intake control valve; the input parameters of the model include gas storage pressure, gas storage minimum drop pressure, air enthalpy value and frequency modulation power.

6. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 5, characterized in that: The volume of the compressed air frequency modulation gas storage area is determined by the following parameters: gas storage pressure, minimum gas storage drop pressure, air enthalpy value and frequency modulation power; the flow area of ​​the intake valve is determined by the minimum gas storage drop pressure, unit capacity and air enthalpy value.

7. The primary frequency modulation rapid response method of the compressed air energy storage system according to claim 6, characterized in that: The primary frequency regulation response control includes: when the compressed air energy storage unit is just started, the air intake control valve controls the unit load to meet the primary frequency regulation upward regulation demand; during the operation of the compressed air energy storage unit, according to the changes in the air intake control valve opening and the pressure in the air storage area, the frequency regulation valve opening is dynamically adjusted to meet the primary frequency regulation upward regulation demand.

8. A primary frequency modulation rapid response system of a compressed air energy storage system, based on the primary frequency modulation rapid response method of a compressed air energy storage system according to any one of claims 1 to 7, characterized in that: It also includes a parameter acquisition module, which acquires the operating parameter data of the compressed air energy storage unit and performs preprocessing; A model operation module is used to preset a compressed air energy storage primary frequency modulation response model and input the preprocessed operation parameter data into the response model; The control execution module performs a frequency modulation response control according to the output of the response model.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the primary frequency modulation rapid response method of the compressed air energy storage system according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the primary frequency modulation rapid response method of a compressed air energy storage system according to any one of claims 1 to 7 are implemented.

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