Thermal power generating unit energy storage frequency modulation system and method

Abstract

The invention relates to a thermal power generating unit energy storage frequency modulation system and method, relates to the technical field of thermal power generation, and aims to improve the response speed and precision of power grid frequency regulation, reduce the frequency modulation burden of a thermal power generating unit and optimize the utilization efficiency of energy. Through cooperative adjustment of the energy storage unit and the thermal power generating unit, the power grid frequency change is responded in real time, and the power grid frequency is stable. Specifically, the energy storage unit provides rapid power output according to the power grid frequency deviation, and the thermal power generating unit adjusts the power output according to an instruction of the frequency modulation control unit so as to meet the power grid load requirement. The adjusting process of the energy storage unit and the thermal power generating unit is optimized through an intelligent control algorithm, power distribution can be dynamically adjusted according to the frequency fluctuation rate and amplitude, and the frequency modulation effect is improved. Through the cooperative adjustment, the frequency modulation precision and the response speed can be remarkably improved, energy waste caused by frequent adjustment of the thermal power generating unit is reduced, fuel consumption is reduced, and the service life of the unit is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal power generation, and in particular to a thermal power unit energy storage frequency modulation system and method. Background Art

[0002] As the world's reliance on renewable energy continues to increase, especially as unstable new energy sources such as wind and solar energy are gradually connected to the power grid, the frequency regulation of the power grid has become increasingly complex. Wind and solar power generation are volatile and intermittent, which makes the frequency fluctuations of the power grid more frequent and drastic, bringing greater challenges to traditional power systems. Therefore, how to efficiently and quickly adjust the frequency of the power grid to ensure the stability of the power grid has become an important issue in the operation of the current power system.

[0003] The frequency stability of the power grid is a key factor in ensuring safe, continuous and efficient power supply. Usually, the power grid frequency is 50Hz or 60Hz. Once the frequency deviates from the standard frequency, it may cause power equipment failure, system instability and even large-scale power outages. In order to cope with power grid frequency fluctuations, the power grid dispatching system usually relies on frequency modulation equipment to adjust the frequency to keep it within a reasonable range.

[0004] In traditional power systems, thermal power units and hydropower units are often used as the main frequency regulation resources. Thermal power units adjust the frequency of the power grid by adjusting the output power of the generator set, controlling the fuel combustion rate and the load of the turbine. However, the frequency regulation response speed of thermal power units is slow, and it usually takes several minutes or even longer to achieve the regulation effect. In addition, the response of thermal power units is affected by the unit load, fuel supply and mechanical equipment inertia, and it is difficult to meet the needs of rapid frequency fluctuations in modern power grids.

[0005] In order to solve the challenges of frequency regulation, energy storage systems have gradually become an indispensable part of power dispatching. Energy storage systems can quickly provide or absorb electrical energy in a short period of time to cope with rapid changes in grid frequency. Currently, common energy storage systems in power systems include:

[0006] Pumped-storage power stations: use electricity during peak hours to pump water to a high place for storage, and then use the water flow to drive the generator to generate electricity. However, pumped-storage power stations have a long construction period, high investment, and limited geographical conditions.

[0007] Battery energy storage system: such as lithium-ion batteries, sodium-sulfur batteries, etc. These systems have a high response speed and can respond to grid frequency changes within milliseconds to minutes. However, the biggest challenge of battery energy storage systems is the high cost and energy density, especially when the scale of energy storage is large, the cost is still a bottleneck that cannot be ignored.

[0008] Supercapacitor energy storage system: Supercapacitors can provide high power output in a very short time, which is very suitable for regulating short-term fluctuations in grid frequency, but their energy density is relatively low, making them suitable for use as fast-response auxiliary regulation equipment.

[0009] Flywheel energy storage system: Flywheel energy storage stores kinetic energy mechanically, has high power density and long service life, and is suitable for dealing with frequency fluctuations in a short period of time.

[0010] With the continuous development of energy storage technology, the coordinated regulation of energy storage and traditional thermal power units has become an effective means to improve the frequency response capability of the power grid. The rapid regulation capability provided by the energy storage system can provide rapid power regulation when the power grid frequency deviation is large, reduce the burden on thermal power units, and improve the response speed and efficiency of the system.

[0011] Although thermal power units dominate the traditional power system, their limitations in frequency regulation are becoming increasingly prominent:

[0012] Slow response speed: Thermal power units need to adjust the power output by adjusting the combustion rate and turbine load, a process that is limited by the inertia of the unit and the fuel supply. It usually takes several minutes to achieve effective frequency regulation, which is insufficient for the rapid fluctuation of the grid frequency.

[0013] Frequent start and stop have a great impact on the loss of the unit: Frequent frequency modulation operations (such as start and stop) will affect the long-term operation stability and service life of the unit. Especially in the power grid with a high proportion of new energy, the frequent adjustment of thermal power units increases the maintenance cost.

[0014] Impact of load fluctuations on unit efficiency: Thermal power units are usually used to provide base load electricity, and the frequency regulation function will cause fluctuations in their output power, thereby reducing the operating efficiency of the unit and increasing fuel consumption.

[0015] The existing energy storage and thermal power unit frequency regulation system still has the following deficiencies:

[0016] Poor coordination of frequency regulation: Currently, the regulation process of energy storage systems and thermal power units is usually carried out independently, lacking intelligent coordination, which may cause the regulation process between the energy storage system and thermal power units to conflict with each other or produce over-regulation, wasting energy.

[0017] Insufficient response speed and accuracy: When the grid frequency changes rapidly, the existing system has a faster response speed of the energy storage system, but the response of the thermal power unit is still slow, making it difficult to achieve real-time and precise regulation.

[0018] High system operating costs: In the combination mode of traditional thermal power units and energy storage systems, frequent adjustments lead to increased fuel consumption of thermal power units. At the same time, the cost of the energy storage system itself (especially large-scale battery energy storage systems) is also relatively high.

[0019] Therefore, we urgently need to design a thermal power unit energy storage frequency regulation system and method to solve the above problems. Summary of the invention

[0020] The purpose of the present invention is to provide a thermal power unit energy storage frequency modulation system and method in view of the deficiencies of the prior art, so as to solve the problems raised in the background technology.

[0021] To achieve the above object, the present invention provides the following technical solutions:

[0022] A thermal power unit energy storage frequency modulation system, the system comprising:

[0023] Thermal power unit host: including boiler, steam turbine and generator, used to adjust the power generation according to the grid demand, where the output power P of the thermal power unit host is thermal The frequency control unit adjusts the frequency according to the grid frequency;

[0024] Energy storage unit: including battery energy storage devices or supercapacitors, used to store electrical energy and provide fast power response when the grid frequency fluctuates. The power output P of the energy storage unit storage The frequency modulation control unit dynamically adjusts according to the frequency deviation;

[0025] Frequency regulation control unit: including frequency monitoring module, frequency deviation calculation module, power distribution module and real-time control module. The frequency regulation control unit monitors the grid frequency in real time, calculates the frequency deviation value, and dynamically distributes the power output of the two to achieve frequency regulation according to the preset frequency regulation strategy and the status of the energy storage unit and the thermal power unit;

[0026] Data acquisition and communication module: used to collect grid frequency, output power of thermal power units, charging status of energy storage units and battery power, and feed back the information to the frequency modulation control unit in real time.

[0027] As a preferred technical solution of the present invention, the frequency modulation control unit further comprises

[0028] Frequency monitoring module: used to collect grid frequency f in real time actual and the target frequency f target and transmit the current grid frequency information to the frequency deviation calculation module;

[0029] Frequency deviation calculation module: used to calculate the magnitude of the power grid frequency deviation value Δf, the calculation formula is:

[0030] Δf=factual -f target ;

[0031] When the frequency deviation value |Δf| exceeds the preset threshold, the frequency modulation mode is entered;

[0032] Power allocation module: It is used to dynamically allocate the power output of thermal power units and energy storage units according to the calculated frequency deviation Δf and grid load demand, and adjust their output power P in real time. thermal and P storage , so that the frequency deviation can be effectively corrected;

[0033] Real-time control module: used to adjust the charging and discharging strategy of the energy storage unit and the power adjustment strategy of the thermal power unit according to the rate and amplitude of the grid frequency change.

[0034] As a preferred technical solution of the present invention, the power allocation module performs power adjustment according to the following power allocation formula:

[0035] P total =P thermal +P storage ;

[0036] in:

[0037] P total The total power required to regulate the system;

[0038] P thermal The frequency regulation power of the thermal power unit is determined by the load regulation range of the thermal power unit;

[0039] P storage It is the frequency modulation power of the energy storage unit, which is determined by the magnitude of the frequency deviation and the current power of the energy storage unit.

[0040] The power output P of the energy storage unit storage Calculated by the following formula:

[0041] P storage = k·|Δf|·(E max -E current );

[0042] Wherein, k is the proportionality coefficient, which reflects the charging and discharging efficiency and maximum power output capacity of the energy storage unit; |Δf| is the deviation amplitude of the grid frequency;

[0043] E max is the maximum capacity of the energy storage unit;

[0044] E current The current remaining power of the energy storage unit.

[0045] As a preferred technical solution of the present invention, the charging power P of the energy storage unitcharge and discharge power P discharge The calculation formulas are:

[0046] P charge =k charge ·(E max -E current );

[0047] P discharge =k discharge |Δf|

[0048] Among them, k charge and k discharge It is the proportional coefficient in the charging and discharging process, which is determined according to the battery characteristics and charging and discharging efficiency of the energy storage unit;

[0049] E max and E current They are the maximum power and current power of the energy storage unit respectively;

[0050] During the frequency regulation process, the energy storage unit decides whether to charge or discharge based on the real-time frequency changes and remaining power, which in turn affects the power regulation of the thermal power unit.

[0051] As a preferred technical solution of the present invention, the frequency modulation control unit uses an adaptive algorithm to adjust the charging and discharging strategy of the energy storage unit according to the change rate and amplitude of the grid frequency, wherein the calculation formula of the frequency deviation change rate is:

[0052]

[0053] Wherein, Δf(t) is the frequency deviation at the current time point; Δf(t-1) is the frequency deviation at the previous time point; Δt is the time interval;

[0054] When the frequency deviation changes at a faster rate, the energy storage unit increases the discharge power and the thermal power unit adjusts its load output;

[0055] When the frequency deviation changes at a slow rate, the energy storage unit gradually stops discharging, and the thermal power unit takes on more frequency regulation tasks.

[0056] As a preferred technical solution of the present invention, the system includes a prediction module, which predicts frequency fluctuations through historical power grid load data and meteorological data, and optimizes the charging and discharging strategy of the energy storage unit in advance according to the predicted fluctuation range to enhance the frequency regulation effect.

[0057] As a preferred technical solution of the present invention, the frequency regulation control unit of the system includes an adaptive regulation module, which dynamically adjusts the charging and discharging power of the energy storage unit to achieve adaptive control of grid frequency stability, thereby maximizing the life of the energy storage device.

[0058] The present invention also provides a method for energy storage frequency regulation of a thermal power unit, the method comprising the following steps:

[0059] Frequency monitoring: Real-time monitoring of grid frequency f actual , and calculate the frequency deviation value Δf through the frequency deviation calculation module; determine the frequency modulation demand: determine whether frequency modulation is required according to the calculated frequency deviation value Δf, and enter the frequency modulation mode when |Δf| is greater than the preset threshold;

[0060] Power allocation: According to the frequency deviation and grid load requirements, the power allocation formula P is used. total =P thermal +P storage Allocate power output of energy storage units and thermal power units;

[0061] Real-time regulation: According to the frequency fluctuation rate and amplitude, the charging or discharging power P of the energy storage unit is adjusted in real time charge and P discharge , and load regulation of thermal power units until the frequency returns to the target value f target .

[0062] As a preferred technical solution of the present invention, in the power distribution step, the power output P of the energy storage unit storage According to the frequency deviation |Δf| and the current power E of the energy storage unit current The relationship is calculated by the following formula:

[0063] P storage = k·|Δf|·(E max -E current );

[0064] Wherein, k is the power coefficient of the energy storage unit, which is determined according to the type of energy storage unit and the regulation strategy; E max and E current They are the maximum power and current power of the energy storage unit respectively.

[0065] As a preferred technical solution of the present invention, in the method, the power regulation of the thermal power unit is performed by the thermal power unit control system according to the following formula:

[0066] P thermal =P target -P storage ;

[0067] Among them, P thermal is the power output of the thermal power unit; P target is the target power output; P storage is the power output of the energy storage unit.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] 1. The present invention significantly improves the response speed and regulation accuracy of the grid frequency by introducing a coordinated regulation mechanism between the energy storage unit and the thermal power unit. The energy storage unit can quickly provide power output and correct the frequency deviation in time when the grid frequency fluctuates greatly, while the thermal power unit accurately adjusts the output power according to the instructions of the frequency regulation control unit. Compared with the traditional thermal power unit frequency regulation alone, the response speed of the system is greatly improved, which can effectively cope with the frequent rapid fluctuations in modern power grids, thereby ensuring the stability of the grid frequency.

[0070] 2. The present invention provides fast frequency regulation through energy storage units, reduces the frequent adjustment of thermal power units during frequency fluctuations, and reduces their load fluctuations. Thermal power units no longer have to bear frequent frequency regulation tasks, thereby reducing the burden on the units and extending the service life of the units. At the same time, it reduces the fuel consumption and maintenance costs of thermal power units and improves the economy of the system. The participation of energy storage units optimizes the energy efficiency of the entire system and reduces the overall cost of power dispatching.

[0071] 3. The present invention uses intelligent control algorithms and adaptive adjustment strategies to dynamically adjust the charging and discharging power of the energy storage unit and the load output of the thermal power unit according to the real-time situation of the grid frequency change, thereby optimizing the energy utilization efficiency. The cooperation between the energy storage unit and the thermal power unit enables the system to avoid over-regulation while ensuring the stability of the grid frequency, thereby maximizing the energy utilization efficiency. This optimized frequency regulation strategy not only reduces the operating cost of the system, but also improves the overall stability and economy of the grid, providing reliable technical support for the sustainable development of the future power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 This is a system block diagram of the thermal power unit energy storage frequency modulation system and method proposed by the present invention;

[0073] Figure 2 This is a method flow chart of the thermal power unit energy storage frequency modulation system and method proposed by the present invention. DETAILED DESCRIPTION

[0074] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0075] The following is combined with Figure 1 , Figure 2With reference to the accompanying drawings and a number of embodiments, specific embodiments of the present invention are described in detail.

[0076] The thermal power unit energy storage frequency regulation system of the present invention can achieve fast and stable grid frequency regulation by accurately calculating the grid frequency deviation (Δf) and dynamically adjusting the power output of the energy storage unit and the power output of the thermal power unit. The system uses the energy storage unit to work in coordination with the thermal power unit and performs real-time regulation according to changes in grid load and frequency fluctuations.

[0077] 1. System composition

[0078] Thermal power unit host (P thermal ): It consists of boilers, steam turbines and generators, and is mainly responsible for providing base load power for the power grid. The thermal power unit adjusts its output power in real time according to the instructions of the frequency regulation control unit.

[0079] Energy storage unit (P storage ): Energy storage devices such as lithium-ion batteries, supercapacitors, and flywheels are responsible for quickly responding to changes in grid frequency. The energy storage unit performs charging and discharging operations according to the fluctuations in grid frequency to adjust the grid frequency.

[0080] Frequency regulation control unit: monitors the grid frequency in real time and calculates the frequency deviation (Δf), and calculates the power output of the energy storage unit and thermal power unit based on the frequency deviation.

[0081] Data acquisition and communication module: collects data such as grid frequency, power output of thermal power units and power of energy storage units in real time, and transmits them to the frequency regulation control unit.

[0082] 2. Calculation of power output of energy storage unit

[0083] Energy storage unit power output (P storage ) is adjusted according to the grid frequency fluctuation and the amount of energy storage unit. The calculation formula is:

[0084] P storage = k·|Δf|·(E max -E current )

[0085] Where: k: adjustment coefficient, which represents the response capability of the energy storage unit.

[0086] |Δf|: The absolute value of the grid frequency deviation. The larger the frequency deviation, the greater the power output of the energy storage unit.

[0087] E max E: Maximum capacity of the energy storage unit. current : Current power of the energy storage unit.

[0088] When the grid frequency deviation is large, the energy storage unit will adjust the frequency by discharging.

[0089] When the grid frequency deviation is small, the energy storage unit will stop discharging and may enter charging mode.

[0090] 3. Regulation of power output of thermal power units

[0091] According to the target power value (P target ) and the power output of the energy storage unit (P storage ), power output of thermal power units (P thermal ) is calculated by the following formula:

[0092] P thermal =P target -P storage ;

[0093] Working principle: When the grid frequency deviation is large, the energy storage unit provides power output (P storage ), power output of thermal power units (P thermal ) is adjusted accordingly so that the total power of the power grid reaches the target value. The thermal power units flexibly adjust the power output according to the regulation of the energy storage unit to help stabilize the power grid frequency.

[0094] 4. Charging and discharging mode

[0095] Discharge mode: When the grid frequency deviation is large, the energy storage unit enters the discharge mode and provides power output. Discharge power P discharge The calculation formula is:

[0096] P discharge =k discharge |Δf|

[0097] Charging mode: When the grid frequency is high, the energy storage unit enters charging mode, and the power output is calculated based on the power difference:

[0098] P charge =k charge ·(E max -E current ).

[0099] Example 1: Thermal power unit frequency regulation system based on lithium-ion battery energy storage unit

[0100] 1. In this embodiment, a lithium-ion battery is used as the energy storage unit. The maximum power of the battery is 30MW and the capacity is 120MWh, which is suitable for the frequency regulation requirements of the power grid with large frequency fluctuations.

[0101] 2. Calculation of power output of energy storage unit

[0102] Assume that the grid frequency deviation Δf = 0.4 Hz, the maximum power of the energy storage unit is 120 MWh, the current power is 60 MWh, and the regulation coefficient k = 0.6.

[0103] The power output of the energy storage unit is:

[0104] P storage =0.6·0.4·(120-60)=14.4MW.

[0105] 3. Calculation of power output of thermal power units

[0106] Assume that the target power P target =500MW, the power output of the thermal power unit is:

[0107] P thermal =500-14.4=485.6MW.

[0108] 4.Charging mode

[0109] When the grid frequency is high, the energy storage unit enters charging mode. Assuming the current power is 40MWh, the charging regulation coefficient k charge =0.5, then the charging power is:

[0110] P charge =0.5·(120-40)=40MW

[0111] Example 2: Frequency regulation system of thermal power generation unit based on supercapacitor energy storage unit

[0112] 1. This embodiment uses a supercapacitor as an energy storage unit, which has an extremely fast response time.

[0113] The energy storage unit has a maximum power of 10MW and a storage capacity of 2MWh, which is suitable for frequency regulation requirements with rapid grid frequency fluctuations.

[0114] 2. Calculation of power output of energy storage unit

[0115] Assuming the grid frequency deviation Δf = 0.3Hz, the discharge regulation coefficient k discharge =0.8, then the power output of the energy storage unit is:

[0116] P storage =0.8·0.3=2.4MW.

[0117] 3. Calculation of power output of thermal power units

[0118] Assume that the target power output of the power grid is P target =200MW, the power output of the thermal power unit is:

[0119] P thermal=200-2.4=197.6MW.

[0120] 4.Charging mode

[0121] When the grid frequency is high, the energy storage unit enters the charging mode, and the charging power is calculated as:

[0122] P charge =0.5·(2-1)=0.5MW.

[0123] Example 3: Frequency regulation system of thermal power generation unit based on flywheel energy storage unit

[0124] 1. This embodiment uses a flywheel energy storage unit, which has a higher power density and a longer service life. The maximum power of the flywheel energy storage unit is 50MW, and the energy storage capacity is 10MWh, which is suitable for a power grid environment with large frequency fluctuations.

[0125] 2. Calculation of power output of energy storage unit

[0126] Assume that the grid frequency deviation Δf = 0.5 Hz, the adjustment coefficient k discharge =0.9, then the power output of the energy storage unit is:

[0127] P storage =0.9·0.5·50=22.5MW.

[0128] 3. Calculation of power output of thermal power units

[0129] Assume that the target power output of the power grid is P target =600MW, the power output of the thermal power unit is:

[0130] P thermal =600-22.5=577.SMW.

[0131] 4.Charging mode

[0132] When the grid frequency is high, the flywheel energy storage unit enters the charging mode, and the charging power is calculated as:

[0133] P charge =0.8·(10-5)=4MW.

[0134] Example 4: Frequency regulation system of thermal power generation unit based on sodium-sulfur battery energy storage unit

[0135] 1. This embodiment uses sodium-sulfur batteries as energy storage units, which have higher energy density and longer service life.

[0136] The maximum power of the energy storage unit is 40MW and the energy storage capacity is 200MWh.

[0137] 2. Calculation of power output of energy storage unit

[0138] Assuming that the grid frequency deviation Δf = 0.3 Hz, the maximum power of the energy storage unit is 200 MWh, the current power is 100 MWh, and the regulation coefficient k = 0.6, the power output of the energy storage unit is:

[0139] P storage =0.6·0.3·(200-100)=18MW.

[0140] 3. Calculation of power output of thermal power units

[0141] Assume that the target power output of the power grid is P target =800MW, the power output of the thermal power unit is:

[0142] P thermal =800-18=782MW.

[0143] 4.Charging mode

[0144] When the grid frequency is high, the energy storage unit enters the charging mode, and the charging power is calculated as:

[0145] P charge =0.5·(200-100)=50MW.

[0146] Example 5: Thermal power unit frequency regulation system based on lead-acid battery energy storage unit

[0147] 1. System configuration and features

[0148] This embodiment uses lead-acid batteries as energy storage units, which have a large capacity and are suitable for medium and long-term frequency regulation. The maximum power of the energy storage unit is 10MW, and the energy storage capacity is 50MWh.

[0149] 2. Calculation of power output of energy storage unit

[0150] Assuming that the grid frequency deviation Δf = 0.2 Hz, the current power is 30 MWh, the maximum power is 50 MWh, and the regulation coefficient k = 0.5, the power output of the energy storage unit is:

[0151] P storage =0.5·0.2·(50-30)=2MW.

[0152] 3. Calculation of power output of thermal power units

[0153] Assume that the target power output of the power grid is P target =300MW, then the power output of the thermal power unit is:

[0154] P thermal =300-2=298MW.

[0155] 4.Charging mode

[0156] When the grid frequency is high, the energy storage unit enters charging mode, and the charging power is:

[0157] P charge =0.4·(50-30)=8MW.

[0158] Example 6: Thermal power unit frequency regulation system based on sodium ion battery energy storage unit

[0159] 1. This embodiment uses sodium ion batteries as energy storage units, which are suitable for longer period frequency modulation.

[0160] The maximum power of the energy storage unit is 25MW and the energy storage capacity is 100MWh.

[0161] 2. Calculation of power output of energy storage unit

[0162] Assuming that the grid frequency deviation Δf = 0.5 Hz, the current power is 60 MWh, the maximum power is 100 MNWh, and the regulation coefficient k = 0.7, the power output of the energy storage unit is:

[0163] P storage =0.7·0.5·(100-60)=14MW.

[0164] 3. Calculation of power output of thermal power units

[0165] Assume that the target power output of the power grid is P target =500MW, the power output of the thermal power unit is:

[0166] P thermal =500-14=486MW.

[0167] 4.Charging mode

[0168] When the grid frequency is high, the energy storage unit enters charging mode, and the charging power is:

[0169] P charge =0.6·(100-60)=24MW.

[0170] In summary, through the above six embodiments, we can see the application of different types of energy storage devices (lithium-ion batteries, supercapacitors, flywheels, sodium-sulfur batteries, lead-acid batteries and sodium-ion batteries) in the frequency regulation system of thermal power units. Each embodiment shows how the energy storage unit adjusts the power output according to the grid frequency deviation and how it works with the thermal power unit to achieve grid frequency stability.

[0171] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in the field. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A thermal power unit energy storage frequency modulation system, characterized in that: The system comprises: Thermal power unit host: including boiler, steam turbine and generator, used to adjust the power generation according to the grid demand, where the output power P of the thermal power unit host is thermal The frequency control unit adjusts the frequency according to the grid frequency; Energy storage unit: including battery energy storage devices or supercapacitors, used to store electrical energy and provide fast power response when the grid frequency fluctuates. The power output P of the energy storage unit storage The frequency modulation control unit dynamically adjusts according to the frequency deviation; Frequency regulation control unit: including frequency monitoring module, frequency deviation calculation module, power distribution module and real-time control module. The frequency regulation control unit monitors the grid frequency in real time, calculates the frequency deviation value, and dynamically distributes the power output of the two to achieve frequency regulation according to the preset frequency regulation strategy and the status of the energy storage unit and the thermal power unit; Data acquisition and communication module: used to collect grid frequency, output power of thermal power units, charging status of energy storage units and battery power, and feed back the information to the frequency modulation control unit in real time.

2. The thermal power unit energy storage frequency modulation system according to claim 1, characterized in that: The frequency modulation control unit comprises: Frequency monitoring module: used to collect grid frequency f in real time actual and the target frequency f target and transmit the current grid frequency information to the frequency deviation calculation module; Frequency deviation calculation module: used to calculate the magnitude of the power grid frequency deviation value Δf, the calculation formula is: Δf=f actual -f target ; When the frequency deviation value |Δf| exceeds the preset threshold, the frequency modulation mode is entered; Power allocation module: It is used to dynamically allocate the power output of thermal power units and energy storage units according to the calculated frequency deviation Δf and grid load demand, and adjust their output power P in real time. thermal and P storage , so that the frequency deviation can be effectively corrected; Real-time control module: used to adjust the charging and discharging strategy of the energy storage unit and the power adjustment strategy of the thermal power unit according to the rate and amplitude of the grid frequency change.

3. The thermal power unit energy storage frequency modulation system according to claim 2 is characterized in that: The power distribution module performs power regulation according to the following power distribution formula: P total =P thermal +P storage ; in: P total The total power required to regulate the system; P thermal The frequency regulation power of the thermal power unit is determined by the load regulation range of the thermal power unit; P storage The frequency modulation power of the energy storage unit is determined by the magnitude of the frequency deviation and the current power of the energy storage unit; The power output P of the energy storage unit storage Calculated by the following formula: P storage =k·|Δf|·(E max -E current ) in: k is the proportionality coefficient, which reflects the charging and discharging efficiency and the maximum power output capacity of the energy storage unit; |Δf| is the deviation amplitude of the grid frequency; E max is the maximum capacity of the energy storage unit; E current The current remaining power of the energy storage unit.

4. The thermal power unit energy storage frequency modulation system according to claim 3 is characterized in that: The charging power P of the energy storage unit charge and discharge power P discharge The calculation formulas are: P charge =k charge ·(AND max -AND current ); P discharge =k discharge ·|Δf|; Among them, k charge and k discharge It is the proportional coefficient in the charging and discharging process, which is determined according to the battery characteristics and charging and discharging efficiency of the energy storage unit; E max and E current They are the maximum power and current power of the energy storage unit respectively; During the frequency regulation process, the energy storage unit decides whether to charge or discharge based on the real-time frequency changes and remaining power, which in turn affects the power regulation of the thermal power unit.

5. The thermal power unit energy storage frequency modulation system according to claim 1, characterized in that: The frequency modulation control unit uses an adaptive algorithm to adjust the charging and discharging strategy of the energy storage unit according to the change rate and amplitude of the grid frequency, wherein the calculation formula of the frequency deviation change rate is: Wherein, Δf(t) is the frequency deviation at the current time point; Δf(t-1) is the frequency deviation at the previous time point; Δt is the time interval; When the frequency deviation changes at a faster rate, the energy storage unit increases the discharge power and the thermal power unit adjusts its load output; When the frequency deviation changes at a slow rate, the energy storage unit gradually stops discharging, and the thermal power unit takes on more frequency regulation tasks.

6. The thermal power unit energy storage frequency modulation system according to claim 1, characterized in that: The system includes a prediction module, which predicts frequency fluctuations through historical grid load data and meteorological data, and optimizes the charging and discharging strategy of the energy storage unit in advance according to the predicted fluctuation range.

7. The thermal power unit energy storage frequency modulation system according to claim 1, characterized in that: The system's frequency regulation control unit includes an adaptive regulation module, which achieves adaptive control of grid frequency stability by dynamically adjusting the charging and discharging power of the energy storage unit.

8. A method for energy storage frequency modulation of a thermal power unit, characterized in that: The method comprises the following steps: Frequency monitoring: Real-time monitoring of grid frequency f actual Calculate the frequency deviation value Δf through the frequency deviation calculation module; Determine frequency modulation requirements: Determine whether frequency modulation is required based on the calculated frequency deviation value Δf. When |Δf| is greater than the preset threshold, enter the frequency modulation mode. Power allocation: According to the frequency deviation and grid load requirements, the power allocation formula P is used. total =P thermal +P storage Allocate power output of energy storage units and thermal power units; Real-time regulation: According to the frequency fluctuation rate and amplitude, the charging or discharging power P of the energy storage unit is adjusted in real time charge and P discharge , and load regulation of thermal power units until the frequency returns to the target value f target .

9. The method for energy storage frequency modulation of a thermal power unit according to claim 8, characterized in that: In the power distribution step, the power output P of the energy storage unit storage According to the frequency deviation |Δf| and the current power E of the energy storage unit current The relationship is calculated by the following formula: P storage =k·|Δf|·(E max -E current ) Wherein, k is the power coefficient of the energy storage unit, which is determined according to the type of energy storage unit and the regulation strategy; E max and E current They are the maximum power and current power of the energy storage unit respectively.

10. The method for energy storage frequency modulation of a thermal power unit according to claim 8, characterized in that: In the method, the power regulation of the thermal power unit is performed by the thermal power unit control system according to the following formula: Pt hermal =P target -P storage ; Among them, P thermal is the power output of the thermal power unit; P target is the target power output; P storage is the power output of the energy storage unit.

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