Energy storage system dynamic power compensation method and system based on multi-working condition self-adaption

Abstract

The present application relates to the technical field of power energy storage control, and particularly relates to a dynamic power compensation method and system for an energy storage system based on multi-working condition self-adaptation, comprising S1: judging whether an active instruction meets an active instruction condition; S2: judging a communication state of an active power collection device of a grid-connected point and an energy management system (EMS); S3: judging whether the active power of the grid-connected point is consistent with the time sequence of the active instruction; S4: judging whether a power converter (PCS) is in a steady-state regulation completion state; S5: obtaining an active power measured value of all the PCSs with a normal current communication state, and calculating total active power of the PCSs; S6: performing power compensation according to an active target; and repeating S1-S6 to continue power compensation. The present application solves the technical problems of the existing power compensation method, such as the inability to adapt to the power loss characteristics and complex operating conditions of the dynamic changes of the energy storage power station.

Description

Technical Field

[0001] This invention relates to the field of power energy storage control technology, and more specifically, to a dynamic power compensation method and system for energy storage systems based on multi-condition adaptive operation. Background Technology

[0002] With the large-scale grid connection of new energy sources such as wind power and photovoltaics, grid power fluctuations have intensified. As an important means of mitigating power fluctuations, energy storage power stations face increasingly higher requirements for power control accuracy. In actual operation, energy losses occur in various components of energy storage power stations, including the battery management system (BMS), power supply system (PCS), transmission lines, transformers, and station power supplies. This results in the actual power output at the grid connection point failing to meet grid connection test requirements and deviating from the theoretical value. If this deviation is not compensated for, national standards will not be met, leading to performance evaluations and revenue losses for the energy storage power station.

[0003] Currently, common power compensation methods mainly employ fixed compensation values, simple linear compensation, and piecewise linear compensation. The fixed compensation method collects paired data of multiple sets of power commands and actual power, calculates the average difference, and then fixes the power compensation amount to the average difference. This method has a single model and cannot adapt to the differences in losses between charging and discharging conditions. The simple linear compensation method establishes a linear model based on two data points: standby state and rated discharge state. Because the actual power loss has a non-linear relationship with the power, this method has a large deviation in the middle power range. The piecewise linear compensation method presets 11 sampling points at 0%, 10%, 20%, ..., 100% of the rated power, and compensates through piecewise linear difference. However, this method relies on a large amount of pre-debugging data, has a long debugging cycle, and the compensation accuracy will decrease when the sampling is insufficient. In addition, it cannot track changes in system loss in real time and is difficult to adapt to loss drift caused by factors such as temperature changes and equipment aging.

[0004] In summary, most existing power compensation methods for energy storage systems rely on static compensation models built from historical and current data, which cannot adapt to the dynamically changing power loss characteristics and complex operating conditions of energy storage power plants. A dynamic power compensation method is needed that can track power loss changes in real time and adapt to abnormal operating conditions. Summary of the Invention

[0005] The purpose of this application is to provide a dynamic power compensation method and system for energy storage systems based on multi-condition adaptive operation, which solves the technical problems existing in the power compensation method, such as the inability to adapt to the dynamic changes in power loss characteristics and complex operating conditions of energy storage power stations.

[0006] To solve the above-mentioned technical problems, the solution adopted in this application is as follows:

[0007] A dynamic power compensation method for energy storage systems based on multi-condition adaptive operation is characterized by the following steps:

[0008] S1: Determine active power command Does the active power command condition meet? If so, then the active power command condition is met. If the conditions for an active power instruction are met, proceed to step S2; otherwise, issue the active power instruction. After the security process is completed, proceed to step S2.

[0009] S2: Determine the communication status between the active power acquisition device at the grid connection point and the energy management system (EMS). If the communication status is normal, proceed to step S3; otherwise, perform data redundancy processing and then proceed to step S3.

[0010] S3: Determine whether the active power at the grid connection point is in accordance with the active power command timing. If the timing is consistent, proceed to step S4; otherwise, perform data synchronization processing and then proceed to step S4.

[0011] S4: Determine whether the converter PCS is in the steady-state regulation completed state. If the converter PCS is in the steady-state regulation completed state, then execute step S5; otherwise, perform steady-state regulation processing and then execute step S5.

[0012] S5: Obtain the measured active power values ​​of all converter PCS with normal current communication status. Calculate the total active power of the converter PCS ;

[0013] S6: Obtain the measured value of active power at the current grid connection point. Total active power based on converter PCS and active instructions Calculate the active power target of the converter PCS And based on the merit target Perform power compensation; enter the next control cycle and repeat S1-S6 to continue power compensation.

[0014] Preferably, the active power command The security procedures include the following steps:

[0015] If there is a power command If the current maximum adjustable power is exceeded, an active power command will be issued. Limiting to boundary value and will The power compensation process continues as a new active power instruction.

[0016] If there is a power command If the value is illegal or the change is abnormal, the active power command of the previous valid power compensation cycle will be retained, and the power compensation process will continue with the new active power command. At the same time, a warning message will be sent to the energy management system (EMS).

[0017] The data redundancy processing includes the following steps:

[0018] Total Active Power Based on Converter PCS and historical average power loss rate Calculate the power estimate at the grid connection point. The estimated power at the grid connection point was used to replace the measured active power at the grid connection point. Then, perform subsequent power compensation processing;

[0019] Calculate the power estimate at the grid connection point The formula is: .

[0020] The data synchronization process is as follows:

[0021] A data synchronization window is initiated. If the active power and active power command timing at the grid-connected point are synchronized within this window, power compensation continues. If data delay still exists, recent data is used to interpolate the measured active power value at the grid-connected point. Prediction is performed to obtain the predicted active power value at the grid connection point. It continues to perform power compensation and sends a data delay warning message to the Energy Management System (EMS).

[0022] Preferably, the active power command is determined in step S1. The specific implementation of whether the active power instruction conditions are met includes the following steps:

[0023] S1.1: Obtain Active Power Command Measured active power at grid connection point Determine active power command Is it within the preset limit range? If yes, execute S1.2; otherwise, execute the active power instruction. After the safety processing, execute S1.2;

[0024] S1.2: Judgment Is it greater than the active dead zone? If yes, proceed to step S2; otherwise, exit the power compensation process.

[0025] Preferably, determining whether the communication status is normal in step S2 includes the following steps:

[0026] S2.1: Determine if the physical connection is normal. If the physical connection is normal, proceed to step S2.2; otherwise, determine that the communication status is abnormal and perform data redundancy processing.

[0027] S2.2: Perform application layer heartbeat detection. If a valid heartbeat response is received within the preset heartbeat period, the application layer heartbeat detection is considered normal, and step S2.3 is executed; otherwise, the communication status is considered abnormal, and data redundancy processing is performed.

[0028] S2.3: Perform data freshness detection. If the difference between the timestamp of the data frame transmitted at the grid connection point and the current system timestamp of the energy management system (EMS) is less than the preset freshness threshold, the data freshness is determined to be normal, and step S2.4 is executed; otherwise, the communication status is determined to be abnormal, and data redundancy processing is performed.

[0029] S2.4: Perform data quality verification and detection. If the data frame of the grid connection point passes the CRC check, the communication status is determined to be normal, and step S3 is executed; otherwise, the communication status is determined to be abnormal, and data redundancy processing is performed.

[0030] Preferably, in S3, it is determined whether the active power at the grid connection point matches the active power command. Timing consistency is achieved through the following steps:

[0031] S3.1: Obtain Active Power Command Generation timestamp ;

[0032] S3.2: Obtain the measured value of active power at the grid connection point. Data timestamp t_ ;

[0033] S3.3: Determine if the condition is met. If this condition is met, it indicates that the measured active power at the grid connection point is correct. It is a merit instruction If the latest response value is found, proceed to step S4; otherwise, it indicates a data delay, and after data synchronization, proceed to step S4.

[0034] Preferably, the specific implementation of S4 includes the following steps:

[0035] Calculate the percentage of power deviation for each converter PCS, and determine whether the percentage of power deviation for each converter PCS is within the deviation threshold of the rated power deviation for each converter PCS. If yes, it means that each converter PCS is in a state of steady-state adjustment completion, and proceed to step S5; otherwise, perform steady-state adjustment processing for the converter PCS.

[0036] The formula for calculating the power deviation percentage of the converter PCS is:

[0037]

[0038] Preferably, the steady-state adjustment process includes the following steps:

[0039] Start a timer, the maximum allowable duration of which can be defined as an integer multiple of the power compensation cycle;

[0040] During the timer's operation, the judgment for step S4 is continuously returned;

[0041] If the converter PCS is in a steady-state adjustment completed state before the timer expires, the timer is immediately stopped and step S5 is executed; if the timer expires and there are still converter PCS not in a steady-state adjustment completed state, it is determined that at least one converter PCS has failed, and the following operation is triggered:

[0042] Based on the converter PCS in a steady-state regulation completed state, the maximum adjustable power range of the energy storage power station system is recalculated and updated.

[0043] Preferably, the specific implementation of S5 includes the following steps:

[0044] S5.1: Traverse all converter PCS, filter out converter PCS with normal communication status and not in a fault shutdown state, record the number as n, and execute step S5.2; if If the power compensation operation is terminated, a converter fault warning message will be sent to the Energy Management System (EMS).

[0045] S5.2: Calculate the total active power of n converters (PCS) ;

[0046] The total active power of n converter PCS The calculation formula is: .

[0047] Preferably, the specific implementation method of S6 includes the following steps:

[0048] S6.1: Calculate the active power target of the converter PCS ;

[0049] Calculate active target The formula is:

[0050]

[0051] S6.2: The active power target calculated in S6.1 Achieving active power target through amplitude limiting protection With meritorious goals The active power control target value is sent to each converter PCS for execution.

[0052] A dynamic power compensation system for energy storage systems based on multi-condition adaptive operation is characterized by comprising:

[0053] The instruction verification module is used to determine whether the active power instructions issued by the power grid dispatch or energy management system meet the validity conditions, and to perform safety processing when they do not meet the conditions.

[0054] The communication status verification module, connected to the instruction verification module, is used to determine the communication status between the active power acquisition device at the grid connection point and the energy management system, and to perform data redundancy processing to obtain the power estimate at the grid connection point when an anomaly occurs.

[0055] The timing consistency verification module is connected to the communication status verification module. It is used to determine whether the timing of the measured active power at the grid connection point is consistent with that of the active power command, and to perform data synchronization processing when they are inconsistent.

[0056] The steady-state judgment module, connected to the timing consistency verification module, is used to determine whether all converter PCS are in the steady-state regulation completed state, and to trigger steady-state regulation processing when they are not in a steady state.

[0057] The power aggregation module, connected to the steady-state judgment module, is used to acquire the measured active power values ​​of all converter PCS with normal communication status and calculate the total active power of the converter PCS. ;

[0058] The power compensation module, connected to the power aggregation module, communication status verification module, and timing consistency verification module, is used to acquire the measured or processed estimated value of active power at the grid connection point and calculate the active power target. After being processed for safety limiting, the data is sent to each PCS for power compensation.

[0059] The technical solution of this application has at least the following advantages and beneficial effects:

[0060] 1. The power compensation method proposed in this invention first determines whether the active power command issued by the power grid energy management system is valid, whether the communication status between the active power acquisition device at the grid connection point and the energy management system is valid, whether the timing of the measured active power value at the grid connection point is consistent with the active power command, and whether the converter is in a steady-state adjustment completed state. By considering these four aspects, the method judges whether various possible operating conditions in the power compensation process meet the requirements for power compensation. When the operating conditions do not meet the requirements, it performs active power command safety processing, data redundancy processing, and data synchronization processing, ensuring that abnormal operating conditions meet the requirements for power compensation, thus allowing power compensation to continue and avoiding interruption of the entire power compensation process due to abnormal operating conditions. Simultaneously, this method can adapt to various operating conditions in the power compensation process and calculates the required power compensation based on the active power command, the power loss between the converter and the grid connection point, and performs flexible power compensation. Compared to the traditional fixed compensation method, which has a single compensation model that cannot adapt to multiple operating conditions, and the segmented compensation method, which suffers from nonlinear relationships leading to large power compensation deviations, this invention avoids these problems by using real-time observation and calculation of power losses. Attached Figure Description

[0061] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] This invention discloses a dynamic power compensation method for energy storage systems based on multi-condition adaptive operation, comprising the following steps:

[0064] S1: Determine active power command Does the active power command condition meet? If so, then the active power command condition is met. If the conditions for an active power instruction are met, proceed to step S2; otherwise, issue the active power instruction. After the security process is completed, proceed to step S2.

[0065] S2: Determine the communication status between the active power acquisition device at the grid connection point and the energy management system (EMS). If the communication status is normal, proceed to step S3; otherwise, perform data redundancy processing and then proceed to step S3.

[0066] S3: Determine whether the active power at the grid connection point is in accordance with the active power command timing. If the timing is consistent, proceed to step S4; otherwise, perform data synchronization processing and then proceed to step S4.

[0067] S4: Determine whether the converter PCS is in the steady-state regulation completed state. If the converter PCS is in the steady-state regulation completed state, then execute step S5; otherwise, perform steady-state regulation processing and then execute step S5.

[0068] S5: Obtain the measured active power values ​​of all converter PCS with normal current communication status. Calculate the total active power of the converter PCS ;

[0069] S6: Obtain the measured value of active power at the current grid connection point. Total active power based on converter PCS and active instructions Calculate the active power target of the converter PCS And based on the merit target Perform power compensation; enter the next control cycle and repeat S1-S6 to continue power compensation.

[0070] Among them, active instructions The active power control target value issued by the power grid dispatch system or the power station's local energy management system (EMS) to the energy storage power station is the expected power value at the grid connection point under ideal conditions.

[0071] meritorious goals The term "active power control target value" refers to the active power control target value issued to the converter PCS after calculation using the power compensation method described above in this invention. This value includes compensation for power losses. Power loss refers to all energy losses during the transmission of electrical energy from the converter PCS output to the grid connection point, including BMS losses, PCS losses, line losses, transformer losses, and station power consumption. In this invention, "power loss" is used... Indicates; among which, The measured active power at the grid connection point refers to the actual active power measured at the connection point between the energy storage power station and the grid. It is the actual grid-connected power after power loss.

[0072] Total active power of converter PCS This refers to the sum of the active power outputs of all converter PCS terminals that are currently communicating normally.

[0073] In some embodiments, S1 determines the active power command. The specific implementation of whether the active power instruction conditions are met includes the following steps:

[0074] S1.1: Obtain Active Power Command Measured active power at grid connection point Determine active power command Is it within the preset limit range? If yes, execute S1.2; otherwise, execute the active power instruction. After the safety processing, execute S1.2;

[0075] S1.2: Judgment Is it greater than the active dead zone? If yes, proceed to step S2; otherwise, exit the power compensation process.

[0076] Among them, S1.1 contains the active command. The preset limit range can be from 0 to the rated power; in S1.2, if Larger than the active dead zone This indicates the active command. Measured active power at grid connection point The power deviation exceeds the power deviation threshold, i.e., the active power dead zone. Power compensation is required; if Less than or equal to active dead zone In this case, no additional power compensation or adjustment of active power command is required.

[0077] Furthermore, active instructions Security procedures include:

[0078] If there is a power command If the current maximum adjustable power is exceeded, an active power command will be issued. Limiting to boundary value and will The power compensation process continues as a new active power instruction.

[0079] If there is a power command If the value is illegal or the change is abnormal, the active power command of the previous valid power compensation cycle will be retained, and the power compensation process will continue with the new active power command. At the same time, a warning message will be sent to the energy management system (EMS).

[0080] Among them, the maximum adjustable power refers to the maximum active power that an energy storage power station can achieve under safe and stable operating conditions.

[0081] It is worth emphasizing that in this step, by judging the validity of the active power command, abnormal situations such as illegal active power commands, exceeding limits, and jumps are eliminated, and countermeasures are set up for these abnormal situations to ensure that the entire power compensation process will not be directly interrupted even when the active power command is abnormal.

[0082] In some embodiments, step S2 determines the communication status between the active power acquisition device at the grid connection point and the energy management system (EMS). If the communication status is normal, step S3 is executed; otherwise, data redundancy processing is performed before executing step S3. This process includes the following steps:

[0083] S2.1: Physical connection detection: Detect the connection status of the transport layer socket. If the socket is in the ESTABLISHED state and the most recent data transmission and reception is within the preset link timeout threshold, the physical connection is determined to be normal, and step S2.2 is executed; otherwise, the communication status is determined to be abnormal and data redundancy processing is performed.

[0084] The preset link timeout threshold can be 100ms;

[0085] S2.2: Application layer heartbeat detection: Periodically send application layer heartbeat request frames to the active power acquisition device at the grid connection point and monitor the reception status of heartbeat response frames; if a valid heartbeat response is received within the preset heartbeat period, the application layer heartbeat detection is determined to be normal, and step S2.3 is executed; otherwise, the communication status is determined to be abnormal and data redundancy processing is performed.

[0086] The preset heartbeat cycle can be set to 500ms.

[0087] S2.3: Data Freshness Detection: Parse the data frames transmitted by the active power acquisition equipment at the grid connection point, extract the sampling timestamp, calculate the difference between the sampling timestamp and the current system time of the energy management system (EMS), if the difference is less than the preset freshness threshold, the data freshness is determined to be normal, and step S2.4 is executed; otherwise, the communication status is determined to be abnormal and data redundancy processing is performed.

[0088] S2.4: Data quality verification: Perform CRC verification on the data frames transmitted by the active power acquisition device at the grid connection point. If the verification passes, the communication status is determined to be normal, and step S3 is executed; otherwise, the communication status is determined to be abnormal, and data redundancy processing is performed.

[0089] Further, data redundancy processing includes:

[0090] Total Active Power Based on Converter PCS and historical average power loss rate Calculate the power estimate at the grid connection point. The estimated power at the grid connection point was used to replace the measured active power at the grid connection point. Then, perform subsequent power compensation processing.

[0091] Among them, the power estimate of the grid connection point is calculated. Calculate using the following formula:

[0092]

[0093] Among them, historical average power loss rate It can be calculated based on historical data recorded in the historical power compensation cycle.

[0094] In this step, the communication status between the active power acquisition device at the grid connection point and the energy management system (EMS) is assessed from several aspects, including physical connection, application-layer heartbeat data, data freshness, and data quality. This process eliminates potential communication failures and establishes contingency plans for situations where abnormal communication occurs and the real-time measured active power values ​​at the grid connection point cannot be received from the acquisition device. At that time, the grid connection point power is estimated based on historical data, and the estimated power value of the grid connection point is used as the basis for subsequent power compensation, thus avoiding the direct interruption of power compensation when the communication status is abnormal, which would cause greater failure.

[0095] In some embodiments, S3 determines whether the active power at the grid connection point matches the active power command. If the timing is consistent, proceed to step S4; otherwise, perform data synchronization processing and then proceed to step S4. The specific implementation includes the following steps:

[0096] S3.1: Obtain Active Power Command Generation timestamp ;

[0097] S3.2: Obtain the measured value of active power at the grid connection point. Data timestamp t_ ;

[0098] S3.3: Determine if the condition is met. If this condition is met, it indicates that the measured active power at the grid connection point is correct. It is a merit instruction If the latest response value is found, proceed to step S4; otherwise, it indicates a data delay, and after data synchronization, proceed to step S4.

[0099] in It can be set to 100ms.

[0100] Furthermore, the data synchronization process is as follows:

[0101] A data synchronization window is initiated. If the active power and active power command timing at the grid-connected point are synchronized within this window, power compensation continues. If data delay still exists, recent data is used to interpolate the measured active power value at the grid-connected point. Prediction is performed to obtain the predicted active power value at the grid connection point. It continues to perform power compensation and simultaneously sends a data delay warning message to the Energy Management System (EMS).

[0102] The data synchronization window can be set to two power compensation cycles. The power compensation cycle of the Energy Management System (EMS) is a fixed-duration periodic cycle, allowing for periodic waiting when data is not synchronized. Recent data can be selected from the active power of the grid connection point in the most recent 10 power compensation cycles as needed. The specific interpolation prediction method can be linear interpolation, and this invention does not limit it.

[0103] It is worth emphasizing that this step verifies the consistency of the timing of the active power commands issued by the Energy Management System (EMS) to the energy storage power station and the active power at the grid connection point. It determines whether the active power at the grid connection point is adjusted and changed in real time in accordance with the active power commands, and performs data synchronization processing when the timing is inconsistent. This avoids continuing to perform power compensation when the timing is inconsistent, as the data used is outdated or distorted, which could lead to new problems.

[0104] In some embodiments, in step S4, it is determined whether the converter PCS is in a steady-state adjustment completed state. If the converter PCS is in a steady-state adjustment completed state, step S5 is executed; otherwise, step S5 is executed after steady-state adjustment processing. Its specific implementation includes the following steps:

[0105] S4.1: Calculate the percentage of power deviation of each converter PCS, and determine whether the percentage of power deviation of each converter PCS is within 2% of the rated power deviation of each converter PCS. If yes, it means that each converter PCS is in the steady-state adjustment completed state, and proceed to step S5; otherwise, perform steady-state adjustment processing of the converter PCS.

[0106] The formula for calculating the power deviation percentage of the converter PCS is as follows:

[0107]

[0108] in For the first The active power command received by the PCS converter; For the first The actual output active power of the converter PCS is fed back in real time. For the first Rated power of the PCS converter; For the first The power deviation percentage of the converter; when When this occurs, it indicates that the converter PCS is in a state of steady-state regulation completion.

[0109] The Energy Management System (EMS) assigns active power commands according to its configured allocation strategy. Decomposed into active power commands for each converter PCS .

[0110] Furthermore, the steady-state regulation process for the converter PCS includes the following steps:

[0111] Start a timer, the maximum allowable duration of which can be defined as an integer multiple of the power compensation cycle;

[0112] During the timer's operation, the judgment for step S4 is continuously returned;

[0113] If the converter PCS is in a steady-state adjustment completed state before the timer expires, the timer is immediately stopped and step S5 is executed; if the timer expires and there are still converter PCS not in a steady-state adjustment completed state, it is determined that at least one converter PCS has failed, and the following operation is triggered:

[0114] Based on the converter PCS in a steady-state regulation completed state, the maximum adjustable power range of the energy storage power station system is recalculated and updated.

[0115] It is worth emphasizing that in this step, the steady state of the converter PCS is judged. By calculating the deviation between its output power and its rated power, the operating conditions with deviations greater than the deviation threshold are eliminated. This avoids the situation where power compensation cannot achieve the expected power compensation effect and may even cause additional faults when the deviation is too large, i.e., the converter PCS is still in an unstable state.

[0116] In some embodiments, S5 obtains the measured active power values ​​of all converter PCS with normal current communication status. Calculate the total active power of the converter PCS Its specific implementation method includes the following steps:

[0117] S5.1: Traverse all converter PCS, filter out converter PCS with normal communication status and not in a fault shutdown state, record the number as n, and execute step S5.2; if If the power compensation operation fails, the converter fault warning message will be sent to the Energy Management System (EMS).

[0118] S5.2: Calculate the total active power of n converters (PCS) ;

[0119] Among them, the total active power of n converter PCS The calculation formula is:

[0120]

[0121] in The measured value of the active power of the i-th converter PCS; Total active power for the converter PCS.

[0122] In some embodiments, the measured value of the active power at the current grid connection point is obtained in S6. Total active power based on converter PCS and active instructions Calculate the active power target of the converter PCS And based on the merit target Perform power compensation; enter the next control cycle, and repeat S1-S6 to continue power compensation; the specific implementation method includes the following steps:

[0123] S6.1: Calculate the active power target of the converter PCS ;

[0124] Among them, the calculation of active power target The formula is:

[0125]

[0126] S6.2: The active power target calculated in S6.1 Achieving active power target through amplitude limiting protection With meritorious goals The active power control target value is sent to each converter PCS for execution.

[0127] Specifically, limiting protection includes power amplitude limiting and power change rate limiting; it also includes limiting the active power target. The amplitude and rate of change are limited within a preset range; the preset range can be set according to the actual scenario and needs, and the present invention does not limit it.

[0128] Another aspect of the present invention discloses a dynamic power compensation system for energy storage systems based on multi-condition adaptive operation, comprising:

[0129] The instruction verification module is used to determine whether the active power instructions issued by the power grid dispatch or energy management system meet the validity conditions, and to perform safety processing when they do not meet the conditions.

[0130] The communication status verification module, connected to the instruction verification module, is used to determine the communication status between the active power acquisition device at the grid connection point and the energy management system, and to perform data redundancy processing to obtain the power estimate at the grid connection point when an anomaly occurs.

[0131] The timing consistency verification module is connected to the communication status verification module. It is used to determine whether the timing of the measured active power at the grid connection point is consistent with that of the active power command, and to perform data synchronization processing when they are inconsistent.

[0132] The steady-state judgment module, connected to the timing consistency verification module, is used to determine whether all converter PCS are in the steady-state regulation completed state, and to trigger steady-state regulation processing when they are not in a steady state.

[0133] The power aggregation module, connected to the steady-state judgment module, is used to acquire the measured active power values ​​of all converter PCS with normal communication status and calculate the total active power of the converter PCS. ;

[0134] The power compensation module, connected to the power aggregation module, communication status verification module, and timing consistency verification module, is used to acquire the measured or processed estimated value of active power at the grid connection point and calculate the active power target. After being processed for safety limiting, the data is sent to each PCS for power compensation.

[0135] The various embodiments of the present invention have now been described in detail. To avoid obscuring the concept of the invention, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions of this invention based on the above description, and the scope of the invention is defined by the appended claims.

Claims

1. A dynamic power compensation method for energy storage systems based on multi-condition adaptive operation, characterized in that, Includes the following steps: S1: Determine active power command Does the active power command condition meet? If so, then the active power command condition is met. If the conditions for an active power instruction are met, proceed to step S2; otherwise, issue the active power instruction. After the security process is completed, proceed to step S2. S2: Determine the communication status between the active power acquisition device at the grid connection point and the energy management system (EMS). If the communication status is normal, proceed to step S3; otherwise, perform data redundancy processing and then proceed to step S3. S3: Determine whether the active power at the grid connection point is in accordance with the active power command timing. If the timing is consistent, proceed to step S4; otherwise, perform data synchronization processing and then proceed to step S4. S4: Determine whether the converter PCS is in the steady-state regulation completed state. If the converter PCS is in the steady-state regulation completed state, then execute step S5; otherwise, perform steady-state regulation processing and then execute step S5. S5: Obtain the measured active power values ​​of all converter PCS with normal current communication status. Calculate the total active power of the converter PCS ; S6: Obtain the measured value of active power at the current grid connection point. Total active power based on converter PCS and active instructions Calculate the active power target of the converter PCS And based on the merit target Perform power compensation; enter the next control cycle and repeat S1-S6 to continue power compensation.

2. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The active command The security procedures include the following steps: If there is a power command If the current maximum adjustable power is exceeded, an active power command will be issued. Limiting to boundary value and will The power compensation process continues as a new active power instruction. If there is a power command If the value is illegal or there is an abnormal jump, the active power command of the previous valid power compensation cycle will be retained, and the power compensation process will continue with the new active power command. At the same time, a warning message will be sent to the energy management system (EMS). The data redundancy processing includes the following steps: Total Active Power Based on Converter PCS and historical average power loss rate Calculate the power estimate at the grid connection point. The estimated power at the grid connection point was used to replace the measured active power at the grid connection point. Then, perform subsequent power compensation processing; Calculate the power estimate at the grid connection point The formula is: ; The data synchronization process is as follows: A data synchronization window is initiated. If the active power and active power command timing at the grid-connected point are synchronized within this window, power compensation continues. If data delay still exists, recent data is used to interpolate the measured active power value at the grid-connected point. Prediction is performed to obtain the predicted active power value at the grid connection point. It continues to perform power compensation and simultaneously sends a data delay warning message to the Energy Management System (EMS).

3. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The active power command is determined in S1. The specific implementation of whether the active power instruction conditions are met includes the following steps: S1.1: Obtain Active Power Command Measured active power at grid connection point Determine active power command Is it within the preset limit range? If yes, execute S1.2; otherwise, execute the active power instruction. After the safety processing, execute S1.2; S1.2: Judgment Is it greater than the active dead zone? If yes, proceed to step S2; otherwise, exit the power compensation process.

4. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The step S2 for determining whether the communication status is normal includes the following steps: S2.1: Determine if the physical connection is normal. If the physical connection is normal, proceed to step S2.2; otherwise, determine that the communication status is abnormal and perform data redundancy processing. S2.2: Perform application layer heartbeat detection. If a valid heartbeat response is received within the preset heartbeat period, the application layer heartbeat detection is considered normal, and step S2.3 is executed; otherwise, the communication status is considered abnormal, and data redundancy processing is performed. S2.3: Perform data freshness detection. If the difference between the timestamp of the data frame transmitted at the grid connection point and the current system timestamp of the energy management system (EMS) is less than the preset freshness threshold, the data freshness is determined to be normal, and step S2.4 is executed; otherwise, the communication status is determined to be abnormal, and data redundancy processing is performed. S2.4: Perform data quality verification and detection. If the data frame of the grid connection point passes the CRC check, the communication status is determined to be normal, and step S3 is executed; otherwise, the communication status is determined to be abnormal and data redundancy processing is performed.

5. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, In S3, it is determined whether the active power at the grid connection point matches the active power command. Timing consistency is achieved through the following steps: S3.1: Obtain Active Power Command Generation timestamp ; S3.2: Obtain the measured value of active power at the grid connection point. Data timestamp t_ ; S3.3: Determine if the condition is met. If this condition is met, it indicates that the measured active power at the grid connection point is correct. It is a merit instruction If the latest response value is found, proceed to step S4; otherwise, it indicates a data delay, and after data synchronization, proceed to step S4. in Set to 100ms.

6. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The specific implementation of S4 includes the following steps: Calculate the percentage of power deviation for each converter PCS, and determine whether the percentage of power deviation for each converter PCS is within the deviation threshold of the rated power deviation for each converter PCS. If yes, it means that each converter PCS is in a state of steady-state adjustment completion, and proceed to step S5; otherwise, perform steady-state adjustment processing for the converter PCS. The formula for calculating the power deviation percentage of the converter PCS is: ； in For the first The active power command received by the PCS converter; For the first The actual output active power of the converter PCS is fed back in real time. For the first The rated power of the PCS converter.

7. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 6, characterized in that, The steady-state adjustment process includes the following steps: Start a timer, the maximum allowable duration of which can be defined as an integer multiple of the power compensation cycle; During the timer's operation, the judgment for step S4 is continuously returned; If the converter PCS is in a steady-state adjustment completed state before the timer expires, the timer is immediately stopped and step S5 is executed; if the timer expires and there are still converter PCS not in a steady-state adjustment completed state, it is determined that at least one converter PCS has failed, and the following operation is triggered: Based on the converter PCS in a steady-state regulation completed state, the maximum adjustable power range of the energy storage power station system is recalculated and updated.

8. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The specific implementation of S5 includes the following steps: S5.1: Traverse all converter PCS, filter out converter PCS with normal communication status and not in a fault shutdown state, record the number as n, and execute step S5.2; if If the power compensation operation is terminated, a converter fault warning message will be sent to the Energy Management System (EMS). S5.2: Calculate the total active power of n converters (PCS) ; The total active power of n converter PCS The calculation formula is: .

9. The dynamic power compensation method for energy storage systems based on multi-condition adaptive operation as described in claim 1, characterized in that, The specific implementation method of S6 includes the following steps: S6.1: Calculate the active power target of the converter PCS ; Calculate active target The formula is: ； S6.2: The active power target calculated in S6.1 Achieving active power target through amplitude limiting protection With meritorious goals The active power control target value is sent to each converter PCS for execution.

10. A dynamic power compensation system for energy storage systems based on multi-condition adaptive operation, characterized in that, include: The instruction verification module is used to determine whether the active power instructions issued by the power grid dispatch or energy management system meet the validity conditions, and to perform safety processing when they do not meet the conditions. The communication status verification module, connected to the instruction verification module, is used to determine the communication status between the active power acquisition device at the grid connection point and the energy management system, and to perform data redundancy processing to obtain the power estimate at the grid connection point when an anomaly occurs. The timing consistency verification module is connected to the communication status verification module. It is used to determine whether the measured value of active power at the grid connection point is consistent with the timing of the active power, and to perform data synchronization processing when they are inconsistent. The steady-state judgment module, connected to the timing consistency verification module, is used to determine whether all converter PCS are in the steady-state regulation completed state, and to trigger steady-state regulation processing when they are not in a steady state. The power aggregation module, connected to the steady-state judgment module, is used to acquire the measured active power values ​​of all converter PCS with normal communication status and calculate the total active power of the converter PCS. ; The power compensation module, connected to the power aggregation module, communication status verification module, and timing consistency verification module, is used to acquire the measured or processed estimated value of active power at the grid connection point and calculate the active power target. After being processed for safety limiting, the data is sent to each PCS for power compensation.

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