A control method for controllable load cluster to participate in frequency modulation of virtual power plant

Abstract

The application discloses a kind of controllable load cluster participate in the control method of virtual power plant frequency modulation, belong to electric power control field, the control method includes: obtaining the power data of virtual power plant in park;Based on the power data, identify the frequency stability risk of virtual power plant in park;Based on the frequency stability risk, judge whether it needs to start temperature control load cluster to adjust;When it needs to start temperature control load cluster to adjust, obtain adjustable load cluster;Based on the adjustable load cluster, obtain mixed control strategy;The mixed control strategy is executed and verified.Solve the problem of insufficient control accuracy and high control resource consumption in the prior art, thereby ensuring that the power control requirements in the park are fully met in power control.

Description

Technical Field

[0001] This application belongs to the field of power control, specifically, it relates to a control method for controllable load clusters to participate in frequency regulation of a virtual power plant. Background Technology

[0002] As the core carrier for integrating distributed photovoltaic, energy storage, and load resources, park-level virtual power plants face severe challenges in frequency control. The output of distributed photovoltaic within the park fluctuates significantly due to factors such as sunlight and temperature. Coupled with the reduced proportion of synchronous power sources, this weakens the frequency regulation capability of virtual power plants. The traditional mode of relying on energy storage for independent frequency regulation is limited by capacity and cost, making it difficult to meet the park's high-frequency, small-amplitude frequency regulation needs.

[0003] Controllable loads, especially variable frequency temperature-controlled loads such as variable frequency air conditioners and heat pumps, constitute the largest proportion of flexible loads in industrial parks. They possess characteristics of continuously adjustable power and high thermal inertia, making them potential frequency regulation resources in cluster response mode. However, existing technologies have significant shortcomings in utilizing temperature-controlled loads for frequency control in virtual power plants within industrial parks. Firstly, core parameters are not extracted based on the time-scale characteristics of the electrical-heat exchange process of temperature-controlled loads, leading to a mismatch between the control model and the actual dynamic response characteristics of the controllable loads, resulting in low regulation accuracy. Secondly, virtual power plant control architectures often employ either a single centralized or decentralized approach. Centralized architectures rely on high-speed communication and real-time computing power, while decentralized architectures require complex virtual inertia modifications to terminals, neither of which are suitable for the small-scale, decentralized operation characteristics of industrial parks. Furthermore, the frequency response domain of temperature-controlled loads is not fully quantified, and excessive consideration is given to user temperature comfort constraints, failing to fully unleash the regulation potential of controllable loads, resulting in low collaborative control efficiency and further causing frequency instability. Therefore, there is an urgent need to propose a frequency stability control method that adapts to industrial park scenarios, accurately extracts controllable load parameters, and balances response speed and regulation efficiency to address the pain points of existing technologies. Summary of the Invention

[0004] To address the issues of low regulation accuracy and excessively high requirements on the entire system in existing technologies, a control method for controlling load clusters to participate in frequency regulation of a virtual power plant is disclosed, specifically:

[0005] A control method for controllable load clusters participating in frequency regulation of a virtual power plant, the control method comprising:

[0006] Obtain power data from virtual power plants within the park;

[0007] Based on the power data, frequency stability risks of virtual power plants within the park are identified.

[0008] Based on the aforementioned frequency stability risk, determine whether it is necessary to activate the temperature-controlled load cluster for adjustment;

[0009] When it is necessary to activate the temperature-controlled load cluster for adjustment, obtain the adjustable load cluster;

[0010] Based on the adjustable load cluster, a hybrid control strategy is obtained;

[0011] The hybrid control strategy was executed and verified.

[0012] Optionally, acquiring power data within the virtual power plant in the park includes:

[0013] Real-time acquisition of all power data from the virtual power plant within the park;

[0014] All the power data is stored.

[0015] Optionally, identifying frequency stability risks of virtual power plants within the park based on the power data includes:

[0016] Based on the aforementioned power data, the real-time output of the photovoltaic system within the park can be obtained;

[0017] Based on the power data, obtain the basic power of the temperature-controlled load cluster within the park;

[0018] Based on the real-time processing of the photovoltaic system in the park and the basic power of the temperature-controlled load cluster, the difference between the load and the output is obtained;

[0019] The frequency deviation and primary frequency regulation dead zone values ​​are compared to identify frequency stability risks of virtual power plants within the park.

[0020] Optionally, determining whether to activate the temperature-controlled load cluster for adjustment based on the frequency stability risk includes:

[0021] When a frequency stability risk is identified, obtain the upward and downward adjustment capabilities of a single temperature control load.

[0022] Based on environmental parameter requirements, obtain the standard function for temperature control load;

[0023] Obtain the temperature error value of a single temperature-controlled load, and analyze whether the temperature regulation conditions are met based on the temperature error value;

[0024] Based on the judgment result of the temperature regulation and the output result of the temperature control load currently participating in the temperature control, it is determined whether it is necessary to start the temperature control load cluster for regulation.

[0025] Optionally, obtaining the standard function for the temperature-controlled load based on environmental parameter requirements includes:

[0026] Obtain the indoor temperature, set temperature, and user comfort threshold of the temperature control load to obtain the environmental parameter requirements;

[0027] Based on the aforementioned environmental parameter requirements, a standard function for the temperature control load is obtained, and the standard function is as follows:

[0028] ,

[0029] Where i represents the temperature-controlled load number; exp() represents the natural exponential function; R represents the equivalent thermal resistance; C represents the equivalent heat capacity; COP represents the cooling efficiency ratio of the temperature-controlled load; T in Indicates indoor temperature; T set Indicates the set temperature; ΔT comfort Indicates the user comfort threshold; T out represents the outdoor temperature; g(i) represents the output signal of the i-th temperature-controlled load.

[0030] Optionally, obtaining the temperature error value of a single temperature-controlled load and analyzing whether the temperature regulation conditions are met based on the temperature error value includes:

[0031] The temperature error value of a single temperature-controlled load is obtained, and the equation for determining the temperature error value is:

[0032] ,

[0033] Where, θ i f represents the percentage of temperature error for the i-th temperature-controlled load; cond This indicates the operating frequency of the temperature-controlled load compressor; This indicates the maximum operating frequency of the temperature control load.

[0034] Optionally, when it is necessary to activate the temperature-controlled load cluster for adjustment, obtaining the adjustable load cluster includes:

[0035] The comparison results of the errors and error thresholds of all temperature-controlled loads are obtained, and the temperature-controlled loads whose errors are not higher than the error thresholds are selected as candidate temperature-controlled loads.

[0036] All the candidate temperature-controlled loads are set into the same cluster array to obtain an adjustable load cluster.

[0037] Optionally, obtaining a hybrid control strategy based on the adjustable load cluster includes:

[0038] Obtain the virtual inertia command and primary frequency regulation command of the adjustable load cluster;

[0039] The virtual inertia command and the primary frequency modulation command are superimposed, and the amplitude of the superimposed command is limited to the adjustment capability range of the adjustable temperature-controlled load cluster to obtain the total frequency modulation command;

[0040] Based on the total frequency regulation command, the power scenario is obtained. When the total frequency regulation command is greater than 0, the power scenario is a power deficit scenario, and otherwise it is a power surplus scenario.

[0041] In the power deficit scenario, the ratio of the upward adjustment amount of a single temperature-controlled load to the total upward adjustment amount of the adjustable load cluster is obtained for proportional allocation. The proportional allocation equation is as follows:

[0042] ,

[0043] Where, ΔP i，up ΔP represents the proportion of the upward adjustment of the i-th temperature control load; total Indicates the master frequency modulation command; ΔP up，i This represents the upward adjustment amount of the i-th temperature control load; This represents the total upward adjustment capability of an adjustable temperature-controlled load cluster;

[0044] In the power surplus scenario, the ratio of the downward adjustment amount of a single temperature-controlled load to the total downward adjustment amount of the adjustable load cluster is obtained and allocated proportionally. The proportional allocation equation is as follows:

[0045] ,

[0046] Where, ΔP i，down This represents the proportion of the downward adjustment amount of the i-th temperature control load; |ΔP total | Represents the absolute value of the master frequency modulation command; ΔP down，i This represents the downward adjustment amount of the i-th temperature control load; This represents the total downward adjustment capability of an adjustable temperature-controlled load cluster;

[0047] When the total frequency regulation command exceeds the regulation capacity of the adjustable temperature control load cluster in the corresponding direction, the energy storage device discharges to supplement the regulation amount in the power deficit scenario and the energy storage device charges to absorb the regulation amount in the power surplus scenario.

[0048] The equation for the discharge compensation adjustment amount is:

[0049] ,

[0050] in, This indicates the amount of energy storage auxiliary adjustment in power deficit scenarios;

[0051] The equation for the discharge compensation adjustment amount is:

[0052] ,

[0053] in, This indicates the amount of energy storage auxiliary adjustment in scenarios with power surplus.

[0054] Optionally, the step of obtaining the virtual inertia command and primary frequency regulation command of the adjustable load cluster includes:

[0055] The equation for determining the virtual inertia is:

[0056] ,

[0057] in, Indicates virtual inertia support power; K H The virtual inertia coefficient is a known quantity; f represents the grid connection point frequency.

[0058] The equation for determining the primary frequency modulation command is:

[0059] ,

[0060] in, Indicates the primary frequency modulation compensation power; K droop f represents the primary frequency modulation droop factor; n This indicates the rated frequency of the power grid.

[0061] Optionally, the execution and verification of the hybrid control strategy includes:

[0062] The frequency after adjustment at the grid connection point is obtained in real time, and the frequency deviation compared with the grid rated frequency is obtained.

[0063] Based on the frequency deviation, the frequency change rate is obtained;

[0064] When the absolute value of the frequency deviation is not higher than the primary frequency modulation dead zone and the frequency change rate is not higher than the safety threshold of the frequency change rate, the hybrid control strategy is executed; otherwise, the hybrid control strategy is adjusted.

[0065] The beneficial effects of this application include:

[0066] 1. Improved control precision. In the technical solution of this application, the time-scale characteristics of the electrical-heat exchange process of the temperature control load are obtained by acquiring various data in real time, and key parameters are extracted from them. Then, a mathematical model is established based on these key parameters. The entire system can be flexibly controlled by using this mathematical model, and the control results meet the control requirements of the entire system. Therefore, precise control of the entire system can be achieved based on this method.

[0067] 2. Adaptation to the park environment is achieved. In the technical solution of this application, by obtaining historical data, the specific analysis results of all the data are obtained, and the entire system is constructed based on the analysis results. Therefore, this method does not require a large amount of computing resources and is more suitable for the computing resource reserves in the park, thus fully achieving adaptation to the park environment. Attached Figure Description

[0068] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the embodiments of this application or the prior art will be briefly introduced below. Obviously, the following description is only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The drawings are used to provide a further understanding of this disclosure and constitute a part of the specification. They are used together with the following detailed description to explain this disclosure, but do not constitute a limitation of this disclosure. In the drawings:

[0069] Figure 1 A flowchart illustrating a control method for a controllable load cluster participating in frequency regulation of a virtual power plant, provided in an embodiment of this application. Detailed Implementation

[0070] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, in the embodiments of this application, "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0071] like Figure 1 The diagram shown is a flowchart of a controllable load cluster participating in frequency regulation of a virtual power plant, according to an embodiment of this application. Specifically:

[0072] S110. Obtain power data from the virtual power plant within the park.

[0073] S120. Based on the power data, identify the frequency stability risks of virtual power plants within the park.

[0074] S130. Based on the frequency stability risk, determine whether it is necessary to activate the temperature-controlled load cluster for adjustment.

[0075] S140. When it is necessary to start the temperature-controlled load cluster for adjustment, obtain the adjustable load cluster.

[0076] S150. Based on the adjustable load cluster, obtain a hybrid control strategy.

[0077] S160. Execute and verify the hybrid control strategy.

[0078] The beneficial effect of the above steps is that they can significantly improve the accuracy of frequency regulation for virtual power plants, and at the same time, they can fully adapt to the frequency regulation scenarios of virtual power plants within the park.

[0079] The following will provide a detailed explanation of all the steps above.

[0080] As described in step S110, the purpose of this step is to acquire all the data that needs to be collected, specifically:

[0081] S111: Obtain all power data of the virtual power plant within the park in real time.

[0082] S112. Store all the power data.

[0083] This involves collecting key parameters from the virtual power plant within the park and storing them in a database.

[0084] Real-time irradiance Photovoltaic panel temperature Photovoltaic installed capacity photovoltaic panel area Energy storage state of charge DC side current of energy storage Maximum charging and discharging power of energy storage Minimum state of charge for energy storage Real-time power of fixed load Temperature-controlled load compressor operating frequency Temperature control load frequency conversion level Temperature-controlled load input voltage Temperature-controlled load output voltage Temperature-controlled load input current Temperature-controlled load output current Maximum operating frequency of temperature control load Minimum operating frequency of temperature control load Indoor temperature outdoor temperature Set temperature User comfort threshold Rated operating power of temperature-controlled load The power corresponding to the maximum operating frequency of the temperature-controlled load The minimum operating frequency of the temperature-controlled load corresponds to the power , grid connection frequency Rated frequency of power grid FM dead zone .

[0085] As described in step S120, the purpose of this step is to determine the potential frequency stability risks of the virtual power plants within the entire park, and then make corresponding adjustments based on the determination results. Specifically:

[0086] S121. Based on the power data, obtain the real-time output of the photovoltaic system in the park.

[0087] S122. Based on the power data, obtain the basic power of the temperature-controlled load cluster in the park.

[0088] S123. Based on the real-time processing of the photovoltaic system in the park and the basic power of the temperature-controlled load cluster, obtain the difference between the load and the output.

[0089] S124. Compare the frequency deviation with the primary frequency regulation dead zone value to identify the frequency stability risk of the virtual power plant in the park.

[0090] Among these methods, the power balance status of the virtual power plant in the park is calculated based on the collected parameters, and the frequency stability risk is assessed.

[0091] The formula for calculating real-time photovoltaic power output is:

[0092]

[0093] in, This refers to the rated efficiency of the photovoltaic system.

[0094] The formula for calculating the base power of a temperature-controlled load cluster is:

[0095]

[0096] Where N represents the number of temperature-controlled loads.

[0097] The formula for calculating the real-time power deficit / surplus of the industrial park is as follows:

[0098]

[0099] in, It provides real-time power output for energy storage.

[0100] Determine the frequency steady state: If If the frequency is unstable, the temperature-controlled load cluster adjustment will be initiated.

[0101] As described in step S130, the purpose of this step is to analyze whether, during the current operation of the virtual power plant, it is necessary to make corresponding adjustments to the power data across the entire park based on the temperature-controlled load cluster. Specifically:

[0102] S131. When it is determined that there is a risk of frequency instability, obtain the upward and downward adjustment capabilities of a single temperature control load.

[0103] The formula for calculating the upward adjustment capacity of a single temperature control unit is as follows:

[0104]

[0105] The formula for calculating the downward adjustment capacity of a single temperature controller is as follows:

[0106] .

[0107] S132. Based on environmental parameter requirements, obtain the standard function of temperature for temperature control load.

[0108] Among them, the indoor temperature, set temperature and user comfort threshold of the temperature control load are obtained to obtain the environmental parameter requirements;

[0109] Based on the aforementioned environmental parameter requirements, a standard function for the temperature control load is obtained, and the standard function is as follows:

[0110] ,

[0111] Where i represents the temperature-controlled load number; exp() represents the natural exponential function; R represents the equivalent thermal resistance; C represents the equivalent heat capacity; COP represents the cooling efficiency ratio of the temperature-controlled load; T in Indicates indoor temperature; T set Indicates the set temperature; ΔT comfort Indicates the user comfort threshold; T out represents the outdoor temperature; g(i) represents the output signal of the i-th temperature-controlled load.

[0112] S133. Obtain the temperature error value of a single temperature-controlled load, and analyze whether the temperature regulation conditions are met based on the temperature error value.

[0113] Among them, the temperature error value of a single temperature-controlled load is obtained, and the equation for determining the temperature error value is:

[0114] ,

[0115] Where, θ i f represents the percentage of temperature error for the i-th temperature-controlled load; cond This indicates the operating frequency of the temperature-controlled load compressor; This indicates the maximum operating frequency of the temperature control load.

[0116] S134. Based on the judgment result of the temperature regulation and the output result of the temperature control load currently participating in the temperature control, determine whether it is necessary to start the temperature control load cluster for regulation.

[0117] in, The value represents the percentage of temperature error for the i-th temperature-controlled load. The smaller the value, the closer the current temperature of the load is to the user's comfort range, and the less impact the adjustment process has on the user experience.

[0118] As described in step S140, the purpose of this step is to obtain an adjustable load cluster, and then control the entire system based on this cluster. Specifically:

[0119] S141. Obtain the comparison results of the errors and error thresholds of all temperature-controlled loads, and obtain the temperature-controlled loads whose errors are not higher than the error thresholds to obtain the candidate temperature-controlled loads.

[0120] S142. Set all the alternative temperature-controlled loads into the same cluster array to obtain an adjustable load cluster.

[0121] Among them, a temperature error threshold is set. Filter out those that meet the requirements The temperature-controlled loads are identified; parameters such as the load number, current inverter speed, rated operating power, and maximum / minimum regulating power of these eligible temperature-controlled loads are integrated to form a controllable temperature-controlled load cluster array. This is used for allocating adjustment commands for subsequent frequency control.

[0122] As described in step S150, the purpose of this step is to make specific adjustments to the power parameters throughout the entire park. Specifically:

[0123] S151. Obtain the virtual inertia command and primary frequency regulation command of the adjustable load cluster.

[0124] The equation for determining the virtual inertia is as follows:

[0125] ,

[0126] in, Indicates virtual inertia support power; K H The virtual inertia coefficient is a known quantity; f represents the grid connection point frequency.

[0127] The equation for determining the primary frequency modulation command is:

[0128] ,

[0129] in, Indicates the primary frequency modulation compensation power; K droop f represents the primary frequency modulation droop factor; n This indicates the rated frequency of the power grid.

[0130] S152. The virtual inertia command and the primary frequency modulation command are superimposed, and the amplitude of the superimposed command is limited to the adjustment capability range of the adjustable temperature control load cluster to obtain the total frequency modulation command.

[0131] S153. Based on the total frequency modulation command, obtain the power scenario. When the total frequency modulation command is greater than 0, the power scenario is a power deficit scenario; otherwise, it is a power surplus scenario.

[0132] S154. In the power deficit scenario, the ratio of the upward adjustment amount of a single temperature-controlled load to the total upward adjustment amount of the adjustable load cluster is obtained and proportionally allocated. The proportional allocation equation is:

[0133] ,

[0134] Where, ΔP i，up ΔP represents the proportion of the upward adjustment of the i-th temperature control load; total Indicates the master frequency modulation command; ΔP up，i This represents the upward adjustment amount of the i-th temperature control load; This represents the total upward adjustment capability of an adjustable temperature-controlled load cluster.

[0135] S155. In the power surplus scenario, the ratio of the downward adjustment amount of a single temperature-controlled load to the total downward adjustment amount of the adjustable load cluster is obtained and allocated proportionally. The proportional allocation equation is:

[0136] ,

[0137] Where, ΔP i，down This represents the proportion of the downward adjustment amount of the i-th temperature control load; |ΔP total | Represents the absolute value of the master frequency modulation command; ΔP down，i This represents the downward adjustment amount of the i-th temperature control load; This represents the total downward adjustment capability of an adjustable temperature-controlled load cluster.

[0138] S156. When the total frequency regulation command exceeds the adjustment capability of the adjustable temperature control load cluster in the corresponding direction, the energy storage device discharges to supplement the adjustment amount in the power deficit scenario and the energy storage device charges to absorb the adjustment amount in the power surplus scenario.

[0139] S157, The equation for the discharge compensation adjustment amount is:

[0140] ,

[0141] in, This indicates the amount of energy storage auxiliary adjustment in scenarios with power shortage.

[0142] S158, The equation for the discharge compensation adjustment amount is:

[0143] ,

[0144] in, This indicates the amount of energy storage auxiliary adjustment in scenarios with power surplus.

[0145] Among these, the aforementioned energy storage auxiliary regulation capacity must meet the engineering operation constraints of the virtual power plant in the park:

[0146] The following must be satisfied in a discharge scenario:

[0147] In charging scenarios, the following must be met:

[0148] The power amplitude constraint must meet the following requirements:

[0149] .

[0150] As described in step S160, the purpose of this step is to further verify the obtained results. If the verification passes, the parameters are adjusted; if it fails, further adjustments are made. Specifically:

[0151] S161. Obtain the adjusted frequency at the grid connection point in real time, and obtain the frequency deviation compared with the grid rated frequency.

[0152] S162. Based on the frequency deviation, obtain the frequency change rate.

[0153] Among them, the frequency after adjustment of the grid connection point is collected in real time. Calculate two frequency stability indicators: frequency deviation. The formula is: Rate of change of frequency: .

[0154] S163. When the absolute value of the frequency deviation is not higher than the primary frequency modulation dead zone and the frequency change rate is not higher than the safety threshold of the frequency change rate, the hybrid control strategy is executed; otherwise, the hybrid control strategy is adjusted.

[0155] Among them, if both of these indicators simultaneously meet the following preset stability thresholds: and .in, This is a frequency modulation dead zone. If the frequency change rate reaches a safe threshold, the frequency of the virtual power plant in the park is determined to be in a stable state, and the current control is terminated; if the above stability threshold is not met, the real-time parameters collected in step S110 are updated, and the control process from step S120 to step S150 is repeated until the frequency stability index meets the preset threshold.

[0156] To better understand the technical solution of this application, the specific implementation results of the disclosed technical solution are now provided, specifically:

[0157] Step 1: Collect key parameters within the virtual power plant of the park and store them in the database.

[0158] Real-time irradiance Photovoltaic panel temperature Photovoltaic installed capacity photovoltaic panel area Energy storage state of charge DC side current of energy storage Maximum charging and discharging power of energy storage Minimum state of charge for energy storage Real-time power of fixed load 100 1.5KW inverter air conditioners, temperature-controlled load compressor operating frequency Temperature control load frequency conversion level Temperature-controlled load input voltage Temperature-controlled load output voltage Temperature-controlled load input current Temperature-controlled load output current Maximum operating frequency of temperature control load Minimum operating frequency of temperature control load Indoor temperature outdoor temperature Set temperature User comfort threshold Rated operating power of temperature-controlled load The power corresponding to the maximum operating frequency of the temperature-controlled load The minimum operating frequency of the temperature-controlled load corresponds to the power , grid connection frequency Rated frequency of power grid FM dead zone .

[0159] Step 2: Calculate the power balance status of the virtual power plant in the park based on the collected parameters, and assess the frequency stability risk.

[0160] The formula for calculating real-time photovoltaic power output is:

[0161]

[0162] in, This refers to the rated efficiency of the photovoltaic system.

[0163] The formula for calculating the base power of a temperature-controlled load cluster is:

[0164]

[0165] Where N represents the number of temperature-controlled loads.

[0166] The formula for calculating the real-time power deficit / surplus of the industrial park is as follows:

[0167]

[0168] in, The initial value is 0, which is for real-time energy output from energy storage.

[0169] Determine the frequency stability state: If the frequency is determined to be unstable, the temperature-controlled load cluster adjustment will be initiated.

[0170] Step 3: Screening Adjustable Load Clusters Based on Temperature-Controlled Load Frequency Response Domain

[0171] The formula for calculating the upward adjustment capacity of a single temperature controller is:

[0172]

[0173] The formula for calculating the downward adjustment capacity of a single temperature controller is as follows:

[0174]

[0175] Based on parameters such as indoor temperature, set temperature, and user comfort threshold stored in the database, a temperature standard function for the temperature-controlled load is established. This function quantifies the deviation of the current temperature of a single temperature-controlled load from the user's comfort range. The formula is as follows:

[0176]

[0177] Where i is the temperature control load number, It is a natural exponential function. For the building's equivalent thermal resistance, The equivalent heat capacity of the building is given by COP=3.2, which is the cooling efficiency ratio of the temperature-controlled load.

[0178] The temperature error value of a single temperature control load is calculated using the following formula. This is used to determine whether the load meets the adjustment conditions;

[0179]

[0180] in, This represents the percentage of temperature error of the temperature-controlled load. The smaller the value, the closer the current temperature of the load is to the user's comfort range, and the less impact the adjustment process has on the user experience.

[0181] Set temperature error threshold , These 100 loads can all be included in the adjustable temperature-controlled load cluster array. This is used for allocating adjustment commands for subsequent frequency control.

[0182] Step 4: Employ a hybrid control strategy set that combines virtual inertia with primary frequency modulation in a hierarchical manner.

[0183] The virtual inertia command is a millisecond-level response command used to match the inertia support requirements of the virtual power plant in the park. The virtual inertia support power is calculated based on the frequency change rate at the grid connection point, using the following formula:

[0184]

[0185] in, This refers to virtual inertia technology.

[0186] The primary frequency regulation command is a second-level response command used to match the frequency regulation deviation requirements of the virtual power plant in the park. The droop control algorithm is used to calculate the primary frequency regulation compensation power, and the formula is as follows:

[0187]

[0188] in, This is the droop factor for primary frequency modulation. For the real-time frequency of the grid connection point, This is the rated frequency of the power grid.

[0189] The overall control command is obtained by superimposing the aforementioned virtual inertia command with the primary frequency regulation command, and limiting the command amplitude to within the adjustment capability range of the adjustable temperature-controlled load cluster. The formula is as follows:

[0190]

[0191] in. This represents the sum of the upward adjustment capabilities of an adjustable temperature-controlled load cluster. The total downward adjustment capability of the adjustable temperature-controlled load cluster is considered. The current system is in a power surplus scenario, so the downward adjustment capability is taken into account.

[0192] In power deficit scenarios (i.e., when ΔP>0): the upward adjustment of a single load is allocated according to its upward adjustment capacity relative to the total upward adjustment capacity of the cluster, as shown in the formula:

[0193]

[0194] in, This refers to the upward adjustment capability of a single temperature control load.

[0195] The current system is in a power surplus scenario (i.e., ΔP < 0): the downward adjustment amount of a single load is allocated according to the proportion of its downward adjustment capacity to the total downward adjustment capacity of the cluster, as shown in the formula:

[0196]

[0197] in, This refers to the downward adjustment capability of a single temperature-controlled load. Each temperature-controlled load needs to be adjusted downwards by 0.176kW, resulting in a single load power of [value missing]. .

[0198] When the amplitude of the cluster's overall control command exceeds the adjustment capability of the adjustable temperature-controlled load cluster in the corresponding direction, energy storage-assisted adjustment is implemented based on the power imbalance scenario in the park. In the power deficit scenario, the energy storage device supplements the adjustment amount by discharging, as shown in the formula:

[0199]

[0200] in, This refers to the auxiliary adjustment amount of energy storage in scenarios with power shortage.

[0201] In scenarios with power surplus, energy storage devices absorb regulation through charging, as shown in the formula:

[0202]

[0203] in, This refers to the auxiliary adjustment amount of energy storage in scenarios with power surplus.

[0204] because The temperature-controlled load cluster can cover the demand without the need for energy storage replenishment.

[0205] The aforementioned energy storage auxiliary regulation must meet the engineering operation constraints of the virtual power plant in the park: In discharge scenarios, it must meet the following:

[0206] In charging scenarios, the following must be met:

[0207] The power amplitude constraint must meet the following requirements:

[0208] Step 5: Dual-index verification and iterative optimization of frequency steady state

[0209] Real-time acquisition of the adjusted frequency of the grid connection point Calculate two frequency stability indicators: frequency deviation. The formula is: Rate of change of frequency: Both of these indicators simultaneously meet the following preset stability thresholds: and .in, This is a frequency modulation dead zone. If the frequency change rate is set to a safe threshold, the frequency of the virtual power plant in the park is determined to be in a stable state, and the current control operation ends. If the stability threshold is not met, the real-time parameters collected in step 1 are updated, and the control process from step 2 to step 4 is repeated until the frequency stability index meets the preset threshold.

[0210] The beneficial effects of this application include:

[0211] 1. Improved control precision. In the technical solution of this application, the time-scale characteristics of the electrical-heat exchange process of the temperature control load are obtained by acquiring various data in real time, and key parameters are extracted from them. Then, a mathematical model is established based on these key parameters. The entire system can be flexibly controlled by using this mathematical model, and the control results meet the control requirements of the entire system. Therefore, precise control of the entire system can be achieved based on this method.

[0212] 2. Adaptation to the park environment is achieved. In the technical solution of this application, by obtaining historical data, the specific analysis results of all the data are obtained, and the entire system is constructed based on the analysis results. Therefore, this method does not require a large amount of computing resources and is more suitable for the computing resource reserves in the park, thus fully achieving adaptation to the park environment.

[0213] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to computer program instructions. The aforementioned computer program can be stored in a non-volatile storage medium, and when executed, it performs the steps of the above method embodiments. Alternatively, if the integrated unit of the present invention is implemented as a software functional module and sold or used as an independent product, it can also be stored in a non-volatile storage medium. Based on this understanding, the technical solution of the embodiments of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a non-volatile storage medium and includes several instructions to cause an electronic device (which may be a personal computer, server, network device, etc.) to execute all or part of the methods described in the various embodiments of the present invention.

[0214] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method for controllable load clusters participating in frequency regulation of a virtual power plant, characterized in that, The control method includes: Obtain power data from virtual power plants within the park; Based on the power data, frequency stability risks of virtual power plants within the park are identified. Based on the aforementioned frequency stability risk, determine whether it is necessary to activate the temperature-controlled load cluster for adjustment; When it is necessary to activate the temperature-controlled load cluster for adjustment, obtain the adjustable load cluster; Based on the adjustable load cluster, a hybrid control strategy is obtained; The hybrid control strategy was executed and verified. The determination of whether to activate the temperature-controlled load cluster for adjustment based on the frequency stability risk includes: When a frequency stability risk is identified, obtain the upward and downward adjustment capabilities of a single temperature control load. Based on environmental parameter requirements, obtain the standard function for temperature control load; Obtain the temperature error value of a single temperature-controlled load, and analyze whether the temperature regulation conditions are met based on the temperature error value; Based on the judgment result of the temperature regulation and the output result of the temperature control load currently participating in the temperature control, it is determined whether it is necessary to start the temperature control load cluster for regulation. The method for obtaining the standard function for temperature control load based on environmental parameter requirements includes: Obtain the indoor temperature, set temperature, and user comfort threshold of the temperature control load to obtain the environmental parameter requirements; Based on the aforementioned environmental parameter requirements, a standard function for the temperature control load is obtained, and the standard function is as follows: ， in, i Indicates the temperature control load number; exp() represents the natural exponential function; R Indicates the equivalent thermal resistance; C Indicates equivalent heat capacity; COP This indicates the cooling efficiency ratio for temperature-controlled loads. T in Indicates indoor temperature; T set Indicates the set temperature; ΔT comfort Indicates the user comfort threshold; T out Indicates the outdoor temperature; g ( i ) indicates the first i Output signal for a temperature-controlled load; The step of obtaining the temperature error value of a single temperature-controlled load and analyzing whether the temperature regulation conditions are met based on the temperature error value includes: The temperature error value of a single temperature-controlled load is obtained, and the equation for determining the temperature error value is: ， in, θ i Indicates the first i The percentage of temperature error of the temperature control load; f cond This indicates the operating frequency of the temperature-controlled load compressor; This indicates the maximum operating frequency of the temperature control load.

2. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 1, characterized in that, The acquisition of power data from the virtual power plant within the park includes: Real-time acquisition of all power data from the virtual power plant within the park; All the power data is stored.

3. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 1, characterized in that, The identification of frequency stability risks of virtual power plants within the park based on the power data includes: Based on the aforementioned power data, the real-time output of the photovoltaic system within the park can be obtained; Based on the power data, obtain the basic power of the temperature-controlled load cluster within the park; Based on the real-time processing of the photovoltaic system in the park and the basic power of the temperature-controlled load cluster, the difference between the load and the output is obtained; The frequency deviation and primary frequency regulation dead zone values ​​are compared to identify frequency stability risks of virtual power plants within the park.

4. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 1, characterized in that, When it is necessary to activate the temperature-controlled load cluster for adjustment, the process of acquiring the adjustable load cluster includes: The comparison results of the errors and error thresholds of all temperature-controlled loads are obtained, and the temperature-controlled loads whose errors are not higher than the error thresholds are selected as candidate temperature-controlled loads. All the candidate temperature-controlled loads are set into the same cluster array to obtain an adjustable load cluster.

5. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 1, characterized in that, The process of obtaining a hybrid control strategy based on the adjustable load cluster includes: Obtain the virtual inertia command and primary frequency regulation command of the adjustable load cluster; The virtual inertia command and the primary frequency modulation command are superimposed, and the amplitude of the superimposed command is limited to the adjustment capability range of the adjustable temperature-controlled load cluster to obtain the total frequency modulation command; Based on the total frequency regulation command, the power scenario is obtained. When the total frequency regulation command is greater than 0, the power scenario is a power deficit scenario, and otherwise it is a power surplus scenario. In the power deficit scenario, the ratio of the upward adjustment amount of a single temperature-controlled load to the total upward adjustment amount of the adjustable load cluster is obtained for proportional allocation. The proportional allocation equation is as follows: ， in, ΔP i，up Indicates the first i The distribution ratio of the upward adjustment amount of the temperature control load; ΔP total Indicates the master frequency modulation command; Δ P up，i Indicates the first i The amount of upward adjustment of the temperature control load; This represents the total upward adjustment capability of an adjustable temperature-controlled load cluster; In the power surplus scenario, the ratio of the downward adjustment amount of a single temperature-controlled load to the total downward adjustment amount of the adjustable load cluster is obtained and allocated proportionally. The proportional allocation equation is as follows: ， in, ΔP i，down Indicates the first i The distribution ratio of the downward adjustment amount of the temperature control load; ΔP total | Indicates the absolute value of the total frequency modulation command; ΔP down，i Indicates the first i The amount of downward adjustment of the temperature control load; This represents the total downward adjustment capability of an adjustable temperature-controlled load cluster; When the total frequency regulation command exceeds the regulation capacity of the adjustable temperature control load cluster in the corresponding direction, the energy storage device discharges to supplement the regulation amount in the power deficit scenario and the energy storage device charges to absorb the regulation amount in the power surplus scenario. The equation for the discharge compensation adjustment amount is: ， in, This indicates the amount of energy storage auxiliary adjustment in power deficit scenarios; The equation for the discharge compensation adjustment amount is: ， in, This indicates the amount of energy storage auxiliary adjustment in scenarios with power surplus.

6. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 5, characterized in that, The process of obtaining the virtual inertia command and primary frequency modulation command of the adjustable load cluster includes: The equation for determining the virtual inertia is: ， in, Indicates the virtual inertia support power; K H This represents the virtual inertia coefficient, which is a known quantity. f Indicates the frequency of grid connection points; The equation for determining the primary frequency modulation command is: ， in, Indicates the primary frequency modulation compensation power; K droop This represents the droop factor of a single frequency modulation. f n This indicates the rated frequency of the power grid.

7. The control method for controllable load clusters participating in frequency regulation of a virtual power plant according to claim 1, characterized in that, The execution and verification of the hybrid control strategy includes: The frequency after adjustment at the grid connection point is obtained in real time, and the frequency deviation compared with the grid rated frequency is obtained. Based on the frequency deviation, the frequency change rate is obtained; When the absolute value of the frequency deviation is not higher than the primary frequency modulation dead zone and the frequency change rate is not higher than the safety threshold of the frequency change rate, the hybrid control strategy is executed; otherwise, the hybrid control strategy is adjusted.

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