Centralized network construction type energy storage converter control method

Abstract

The invention discloses a centralized network construction type energy storage converter control method. The energy storage converter control method comprises the following steps: in response to the situation that the continuously acquired state parameters of the power grid voltage of the energy storage converter or the energy storage battery exceed a preset normal range, calculating a frequency reference value according to the latest power grid voltage and the state parameters of the energy storage battery; parameters of a V / F controller are adaptively set based on the frequency reference value; and starting the V / F controller, and switching the control mode of the energy storage converter from the P / Q control mode to the V / F control mode by a smooth transition strategy. In this way, the power stability of the energy storage converter in the control mode switching process can be improved.

Description

Technical Field

[0001] The present application relates to the field of photoelectric converters, and in particular to a control method for a centralized grid-type energy storage converter. Background Art

[0002] The dynamic performance of the energy storage converter during the process of switching the control mode from P / Q control mode to V / F control mode may not meet the actual requirements. This may cause the system to become unstable or power fluctuate when the control mode is switched, which will have an adverse effect on the performance of the system and cause the system to become unstable or performance degraded in complex environments. Summary of the invention

[0003] The present application mainly provides a centralized grid-type energy storage converter control method to solve the problem of power fluctuation when switching control modes.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a centralized grid-type energy storage inverter control method, including: in response to the continuously acquired grid voltage of the energy storage inverter or the state parameters of the energy storage battery exceeding the preset normal range, calculating the frequency reference value according to the latest grid voltage and the state parameters of the energy storage battery; adaptively setting the parameters of the V / F controller based on the frequency reference value; starting the V / F controller to switch the control mode of the energy storage inverter from the P / Q control mode to the V / F control mode with a smooth transition strategy.

[0005] In some embodiments, starting the V / F controller to switch the control mode of the energy storage inverter from a P / Q control mode to a V / F control mode with a smooth transition strategy includes: dynamically adjusting the active power and reactive power output by the energy storage inverter through a feedback control algorithm to smoothly match the requirements of the V / F control mode.

[0006] In some embodiments, it is characterized in that the active power and reactive power output by the energy storage inverter are dynamically adjusted through a feedback control algorithm to smoothly match the requirements of the V / F control mode, including: calculating the active power output by the energy storage inverter and the target active power; based on the amplitude difference between the active power and the target active power, adjusting the voltage amplitude output by the energy storage inverter until the amplitude difference is less than a preset amplitude error threshold.

[0007] In some embodiments, the voltage amplitude adjustment formula is:

[0008] Among them, V adjusted is the adjusted voltage amplitude, V initialis the voltage amplitude before adjustment, Kp is the adjustment coefficient, ΔP is the amplitude difference between the active power and the target active power, P acture is the current active power, P target is the target active power.

[0009] In some embodiments, the active power and reactive power output by the energy storage inverter are adjusted through a feedback control algorithm to smoothly match the requirements of the V / F control mode, including: calculating the reactive power output by the energy storage inverter and the target reactive power; based on the phase difference between the reactive power and the target reactive power, adjusting the current phase output by the energy storage inverter until the phase difference is less than a preset phase error threshold.

[0010] In some embodiments, the current phase adjustment formula is:

[0011] Among them, φ adjusted is the adjusted current phase, φ initial is the current phase before adjustment, Kq is the adjustment coefficient, Δθ is the amplitude difference between the active power and the target active power, θ acture is the current active power phase, θ target is the target active power phase.

[0012] In some embodiments, adaptively setting the parameters of the V / F controller based on the frequency reference value includes: adaptively adjusting the output frequency and voltage amplitude set point of the V / F controller based on the grid voltage and the frequency reference value.

[0013] In some embodiments, the adaptively adjusting the output frequency and voltage amplitude set point of the V / F controller based on the grid voltage and the frequency reference value includes: constructing a voltage output variation model of the energy storage inverter based on historical grid voltage; calling the voltage output variation model to predict the future grid voltage, and adjusting the output frequency and voltage amplitude set point of the V / F controller based on the prediction result; and updating the voltage output variation model based on the grid voltage obtained in real time.

[0014] In order to solve the above technical problems, another technical solution adopted by the present application is: providing a storage medium on which program data is stored, and when the program data is executed by a processor, the steps of the energy storage converter control method as described above are implemented.

[0015] The present application also provides a computer device, including a processor and a memory connected to each other, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the energy storage converter control method as described above are implemented.

[0016] The beneficial effects of the present application are as follows: Different from the prior art, the present application discloses a centralized grid-type energy storage inverter control method, storage medium and computer equipment. In response to the grid voltage of the energy storage inverter or the state parameters of the energy storage battery exceeding the preset normal range, the frequency reference value is calculated according to the latest grid voltage and the state parameters of the energy storage battery for subsequent power calculation and parameter update; the parameters of the V / F controller are adaptively set based on the frequency reference value, so that the output after switching is more in line with the current abnormal state of the energy storage inverter, so that the switching from the P / Q control mode to the V / F control mode is more conducive to the stable output of the energy storage inverter; the V / F controller is started, and the control mode of the energy storage inverter is switched from the P / Q control mode to the V / F control mode with a smooth transition strategy, so as to avoid the output power fluctuation of the energy storage inverter due to excessive parameter changes during the switching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which: Figure 1 It is a flow chart of an embodiment of a centralized grid-type energy storage converter control method provided by the present application; Figure 2 Yes Figure 1 A schematic diagram of a flow chart of an embodiment of step 20 in the method shown; Figure 3 Yes Figure 1 A schematic diagram of a flow chart of an embodiment of step 30 in the method shown; Figure 4 Yes Figure 1 A schematic flow chart of another embodiment of step 30 in the method shown; Figure 5 It is a structural schematic diagram of an embodiment of a storage medium provided by the present application; Figure 6 It is a structural diagram of an embodiment of a computer device provided by the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] The terms "first", "second", "third" in the embodiments of the present application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0020] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0021] See also Figure 1 , Figure 1 1 is a flow chart of an embodiment of a centralized grid-type energy storage converter control method provided by the present application, and the energy storage converter control method includes: Step 10: In response to the continuously acquired grid voltage of the energy storage converter (ESC) or the state parameter of the energy storage battery exceeding a preset normal range, a frequency reference value is calculated according to the latest grid voltage and the state parameter of the energy storage battery.

[0022] Specifically, the grid voltage of the energy storage converter and the state parameters of the energy storage battery are monitored in real time to continuously obtain the latest grid voltage of the energy storage converter and the state parameters of the energy storage battery, and ensure the accuracy and integrity of the data. The collected data is pre-processed, including data cleaning, filtering and calibration, to eliminate noise and interference.

[0023] Safety thresholds are set for the grid voltage and energy storage battery status parameters. When the parameters exceed these thresholds, it is considered that the output of the energy storage inverter has undergone abnormal changes. At this time, the original P / Q control mode is no longer applicable to the current output conditions and the control mode needs to be readjusted.

[0024] Use an oscilloscope to measure the waveform of the grid voltage, find the period T from the waveform graph, and then calculate the frequency reference value f=1 / T.

[0025] Optionally, after calculation, the calculated frequency reference value is compared with a preset normal range to verify its rationality and accuracy. If the calculated result exceeds the preset range, it is necessary to adjust the grid voltage or the state parameters of the energy storage battery according to the actual situation and recalculate the frequency reference value.

[0026] Specifically, the data types obtained from the grid voltage include the amplitude, phase or frequency of the grid voltage; the data types obtained from the state parameters of the energy storage battery include the voltage, current, temperature or state of charge (SOC) of the energy storage battery.

[0027] Step 20: Adaptively set the parameters of the V / F controller based on the frequency reference value.

[0028] The frequency reference value is the basis for setting the parameters of the V / F controller. It is usually determined based on factors such as the rated frequency of the motor, load characteristics, and grid voltage. The frequency reference value is dynamically adjusted by real-time monitoring of the grid voltage and the state parameters of the energy storage battery, combined with the preset safety threshold and operation strategy. V / F control refers to the proportional relationship control of voltage (Voltage) and frequency (Frequency), which is mainly used for variable frequency speed regulation of AC asynchronous motors. Its basic principle is to maintain the proportional relationship between output voltage and output frequency to maintain the constant magnetic flux of the motor, thereby avoiding the occurrence of weak magnetic field and magnetic saturation.

[0029] Specifically, the output frequency and voltage amplitude set points of the V / F controller are adaptively adjusted based on the grid voltage and frequency reference values.

[0030] When the grid voltage changes, the V / F controller can monitor this change in real time. According to the increase or decrease of the grid voltage, the controller will adjust the output voltage set point accordingly to keep the motor flux constant. If the grid voltage is too high, the controller will reduce the output voltage set point to prevent the motor from saturating the motor magnetic circuit and increasing the excitation current, which will cause the motor temperature to rise too high. On the contrary, if the grid voltage is too low, the controller will increase the output voltage set point to ensure the normal operation of the motor.

[0031] The change of grid frequency will also be monitored in real time by the V / F controller. When the grid frequency increases, the reactive power of the generator increases and the reactive power of the user decreases, causing the grid voltage to rise. At this time, the controller will lower the set point of the output frequency to keep the motor speed stable. When the grid frequency decreases, the reactive power of the generator decreases and the reactive power of the user increases, which may cause the grid voltage to drop. At this time, the controller will increase the set point of the output frequency to compensate for the impact of the decrease in grid frequency on the motor speed.

[0032] Further, see Figure 2 , step 20 further includes: Step 21: Construct a voltage output variation model of the energy storage converter based on the historical grid voltage.

[0033] Acquire long-term historical grid voltage data from the grid monitoring system, including voltage amplitude, frequency, and timestamp, and extract features that affect voltage changes, such as time (hours, days, weeks, months, etc.), season, climate conditions, etc.

[0034] The voltage output change model can select a suitable prediction model according to the characteristics of the data and the complexity of the problem, such as a time series analysis model (such as ARIMA, SARIMA), a machine learning model (such as support vector machine SVM, random forest RF, neural network NN, etc.) or a deep learning model (such as LSTM, GRU, etc.), and this application does not impose any specific restrictions on this.

[0035] During the model training process, the preprocessed historical data is used to train the model, with the goal of learning how the grid voltage changes over time. After the training is completed, the performance of the model is evaluated using methods such as holdout and cross-validation to ensure that the model can accurately predict future grid voltages.

[0036] Step 22: Call the voltage output change model to predict the future grid voltage, and adjust the output frequency and voltage amplitude set point of the V / F controller based on the prediction results.

[0037] According to the current time and other relevant features, an input feature set is constructed and input into the trained voltage output variation model to obtain the future grid voltage forecast value. Based on the predicted grid voltage, the new output frequency and voltage amplitude set points are calculated according to the V / F control strategy. Optionally, the output frequency and voltage amplitude set points are further adjusted in combination with factors such as the rated voltage and rated frequency of the motor and the fluctuation range of the grid voltage.

[0038] The new set point is sent to the V / F controller, which adjusts its output to match the predicted grid voltage by changing the inverter's PWM (pulse width modulation) waveform, adjusting the converter's duty cycle, etc.

[0039] Step 23: Update the voltage output variation model based on the real-time acquired grid voltage.

[0040] Get new grid voltage data from the grid monitoring system in real time. Update the model periodically or based on the degree of data change to reflect the latest changes in grid voltage through incremental learning, online learning, or retraining the model. Continuously monitor the model's prediction performance to ensure that the model can always accurately predict grid voltage.

[0041] Optionally, new data points are used to fine-tune the model's weights; when new data arrives, instead of retraining the entire model, only a portion of the model's parameters are updated to quickly adapt to the new data. The model can be updated based on new data immediately upon receiving new data, without having to wait to obtain the entire dataset.

[0042] Set up an automated monitoring process on the voltage output change model and regularly calculate the model's prediction error, such as mean square error (MSE) and mean absolute error (MAE), to evaluate the model's prediction performance. Use statistical methods or machine learning algorithms to detect outliers in the model's predictions, where outliers are used to indicate that the model fails to correctly capture changes in grid voltage. Generate a performance report based on the monitored data, including indicators such as the model's prediction accuracy, stability, and response time, so that the model can be continuously improved.

[0043] When the data changes significantly or the model performance drops significantly, consider retraining the entire model; specifically, collect data over a period of time and use this data to train a new model.

[0044] Step 30: Start the V / F controller to switch the control mode of the energy storage converter from the P / Q (active power / reactive power) control mode to the V / F (voltage / frequency) control mode using a smooth transition strategy.

[0045] In the P / Q control mode, the energy storage converter focuses on the output of active power and reactive power to adapt to the power demand of the grid. However, when the grid fails or island operation is required, the V / F control mode can maintain the voltage and frequency stability of the microgrid or isolated grid, thereby ensuring the continuous operation of the grid.

[0046] According to the requirements of the power grid and the characteristics of the energy storage converter, set the parameters of the V / F controller, including the target voltage amplitude, frequency range, response speed, etc.

[0047] According to the system requirements and the response capability of the energy storage converter, a reasonable transition time is determined to ensure a smooth and impact-free switching process.

[0048] A smooth transition curve is formulated to gradually adjust the output of the energy storage converter during the transition time to transition from the P / Q control mode to the V / F control mode.

[0049] Start the V / F controller and put it in standby mode, waiting to receive the switching command. The control system sends a switching command to the energy storage converter, instructing it to start the transition from P / Q control mode to V / F control mode. After receiving the switching command, the energy storage converter begins to adjust its output according to the predetermined transition curve. This usually involves gradually reducing the output in P / Q control mode and gradually increasing the output in V / F control mode until it is fully switched to V / F control mode.

[0050] Specifically, the active power and reactive power output by the energy storage converter are dynamically adjusted through a feedback control algorithm to smoothly match the requirements of the V / F control mode.

[0051] Use sensors or measuring devices to monitor the output active power and reactive power of the energy storage inverter in real time, and monitor the voltage and frequency of the power grid at the same time to obtain the real-time status of the system.

[0052] Based on the real-time monitoring data, the difference between the active power and reactive power output by the energy storage inverter and the target power is calculated to evaluate the fluctuation of the grid voltage and frequency, thereby determining the direction and magnitude of the adjustment.

[0053] According to the calculated difference, adjust the control parameters of the energy storage converter, such as voltage setting value, frequency setting value, power factor, etc. Ensure that the adjusted parameters can smoothly match the requirements of the V / F control mode while maintaining the stability and reliability of the power grid.

[0054] After adjusting the control parameters, monitor the output of the energy storage converter and the grid status again. If there is still a difference, continue to adjust the control parameters until the desired matching effect is achieved.

[0055] The feedback control algorithm is a control method based on the difference between the system output and the expected output. In the control of the energy storage converter, the algorithm calculates the difference between the actual value and the expected value by real-time monitoring of the output active power and reactive power of the energy storage converter, as well as the voltage and frequency of the power grid, and adjusts the control parameters of the energy storage converter accordingly to achieve smooth matching of the V / F control mode requirements.

[0056] The V / F control mode enables the energy storage converter to adjust the output voltage and frequency as needed to meet the needs of different loads. This adaptability helps to maintain stable operation of the load and avoid equipment failure or performance degradation caused by voltage or frequency fluctuations. At the same time, the V / F controller also has a high response speed and control accuracy, and can quickly adjust the output voltage and frequency to respond to changes in the power grid. This fast response capability helps reduce the fluctuation and instability of the power grid and improve the overall performance of the system.

[0057] The smooth transition strategy ensures seamless switching from P / Q control mode to V / F control mode. This switching reduces the fluctuation and instability of the power grid and improves the reliability and stability of the system. At the same time, it also reduces the risk of equipment damage or power grid failure that may be caused by improper operation during the switching process.

[0058] Further, see Figure 3 , step 30 comprises: Step 31: Calculate the active power output by the energy storage converter and the target active power.

[0059] Active power is the actual power consumed in an AC circuit, which represents the conversion or consumption of electrical energy per unit time. For an energy storage converter, its output active power can be calculated by measuring its output voltage, current and the phase difference between them.

[0060] The formula for calculating active power is as follows:

[0061] Where V is the effective value of the output voltage, I is the effective value of the output current, θ is the phase difference between the output voltage and the output current, and cos(θ) is the power factor.

[0062] Target active power P target It is the expected value of the active power that the energy storage converter should output. The target active power value needs to be determined according to the needs of the power system, the state of the energy storage system and the control strategy.

[0063] For example, the output voltage of the energy storage converter is 230V, the output current is 10A, and the phase difference between the voltage and current is 0° (that is, the power factor is 1). Then, the output active power is: ; According to the grid demand and energy storage status, the target active power is determined to be 2000W, then: P target =2000W.

[0064] Step 32: Based on the amplitude difference between the active power and the target active power, adjust the voltage amplitude output by the energy storage converter until the amplitude difference is less than a preset amplitude error threshold.

[0065] Through control algorithms such as proportional control (P control) and proportional-integral control (PI control), the voltage amplitude ΔV that needs to be adjusted is calculated based on the error ΔP and a control gain Kp.

[0066] First, the amplitude difference between the target active power and the actual active power is calculated. If |ΔP|> the amplitude error threshold, the adjustment step is entered; otherwise, the current state is maintained. The voltage amplitude change ΔV that needs to be adjusted is calculated according to the control algorithm, and the new output voltage amplitude of the energy storage converter is set using the API.

[0067] Specifically, the voltage amplitude adjustment formula is:

[0068] Among them, V adjusted is the adjusted voltage amplitude, V initial is the voltage amplitude before adjustment, Kp is the adjustment coefficient, ΔP is the amplitude difference between the active power and the target active power, P acture is the current active power, P target is the target active power.

[0069] Further, see Figure 4 , step 30 further includes: Step 33: Calculate the reactive power output by the energy storage converter and the target reactive power.

[0070] Reactive power is the power portion that, in addition to providing active power, can be adjusted according to grid demand or control strategy, is not consumed but can affect the phase relationship of grid voltage and current.

[0071] The formula for calculating reactive power is as follows:

[0072] Where V is the effective value of the output voltage, I is the effective value of the output current, and θ is the phase difference between the output voltage and the output current.

[0073] Target reactive power Q target It is the reactive power value expected to be output by the energy storage converter or other reactive power compensation equipment in order to meet the requirements of grid stability, voltage quality and economy. The target active power is set according to the actual situation of the grid and the control strategy of the operator.

[0074] Step 34: Based on the phase difference between the reactive power and the target reactive power, adjust the current phase of the energy storage converter output until the phase difference is less than a preset phase error threshold.

[0075] Determine the target reactive power based on the grid demand or ESC control strategy, and calculate the current phase corresponding to the target reactive power. Calculate the current phase angle that needs to be adjusted based on the current phase difference, thereby calculating the required phase adjustment between the current reactive power and the target reactive power. The calculated phase adjustment is performed using a current controller or a phase controller of the energy storage converter to adjust the PWM signal of the energy storage converter to change the phase of the output current.

[0076] Specifically, the adjustment formula of the current phase is:

[0077] Among them, φ adjusted is the adjusted current phase, φ initial is the current phase before adjustment, Kq is the adjustment coefficient, Δθ is the amplitude difference between the active power and the target active power, θ acture is the current active power phase, θ target is the target active power phase.

[0078] See also Figure 5 , Figure 5 It is a structural diagram of an embodiment of the storage medium provided by the present application.

[0079] The storage medium 300 stores program data 310. When the program data 310 is executed by the processor, the following is achieved: Figure 1 The steps of the energy storage converter control method are described.

[0080] The program data 310 is stored in a storage medium 300, and includes a number of instructions for enabling a network device (such as a router, a personal computer, a server, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application.

[0081] Optionally, the storage medium 300 may be a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disk, or other medium that can store program data.

[0082] See also Figure 6 , Figure 6 It is a structural schematic diagram of an embodiment of a computer device provided by the present application.

[0083] The computer device 400 includes a processor 420 and a memory 410 which are connected to each other. The memory 410 stores a computer program. When the processor 420 executes the computer program, the steps of the energy storage converter control method described above are implemented.

[0084] Different from the prior art, the present application provides a centralized grid-type energy storage converter control method, storage medium and computer device. A smooth transition strategy is used to ensure seamless switching from P / Q control mode to V / F control mode. This switching reduces the fluctuation and instability of the power grid and improves the reliability and stability of the system. At the same time, it also reduces the risk of equipment damage or power grid failure that may be caused by improper operation during the switching process; starting the V / F controller and switching the control mode of the energy storage converter from the P / Q control mode to the V / F control mode with a smooth transition strategy can significantly improve the stability, reliability and adaptability of the power grid. At the same time, the parameters of the V / F controller are set in an adaptive manner, and the parameters of the V / F controller can be adjusted in real time according to the changes in the power grid and the load, thereby ensuring that the system can respond quickly to these changes. This helps to reduce the response time of the system and improve the dynamic performance of the system; through adaptive parameter setting, the V / F controller helps to more accurately control the output voltage and frequency, thereby maintaining the stable operation of the centralized grid-type energy storage converter.

[0085] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the storage medium embodiment and the computer device embodiment, since they are basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0086] The present application can be used in many general or special computing system environments or configurations, such as personal computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, network PCs, minicomputers, and distributed computing environments including any of the above systems or devices.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not performed.

[0088] The above descriptions are merely embodiments of the present application and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A centralized grid-type energy storage converter control method, characterized in that: include: In response to the continuously acquired grid voltage of the energy storage converter or the state parameter of the energy storage battery exceeding a preset normal range, a frequency reference value is calculated according to the latest grid voltage and the state parameter of the energy storage battery; Adaptively setting parameters of a V / F controller based on the frequency reference value; The V / F controller is started to switch the control mode of the energy storage converter from the P / Q control mode to the V / F control mode using a smooth transition strategy.

2. The energy storage converter control method according to claim 1, characterized in that: The starting of the V / F controller to switch the control mode of the energy storage converter from the P / Q control mode to the V / F control mode with a smooth transition strategy includes: The active power and reactive power output by the energy storage converter are dynamically adjusted through a feedback control algorithm to smoothly match the requirements of the V / F control mode.

3. The energy storage converter control method according to claim 2, characterized in that: The active power and reactive power output by the energy storage converter are dynamically adjusted by a feedback control algorithm to smoothly match the requirements of the V / F control mode, including: Calculating the active power output by the energy storage converter and the target active power; Based on the amplitude difference between the active power and the target active power, the voltage amplitude output by the energy storage converter is adjusted until the amplitude difference is smaller than a preset amplitude error threshold.

4. The energy storage converter control method according to claim 3, characterized in that: The voltage amplitude adjustment formula is: Among them, V adjusted is the adjusted voltage amplitude, V initial is the voltage amplitude before adjustment, Kp is the adjustment coefficient, ΔP is the amplitude difference between the active power and the target active power, P acture is the current active power, P target is the target active power.

5. The energy storage converter control method according to claim 2, characterized in that: The active power and reactive power output by the energy storage converter are adjusted by a feedback control algorithm to smoothly match the requirements of the V / F control mode, including: Calculating the reactive power output by the energy storage converter and the target reactive power; Based on the phase difference between the reactive power and the target reactive power, the current phase output by the energy storage converter is adjusted until the phase difference is smaller than a preset phase error threshold.

6. The energy storage converter control method according to claim 5, characterized in that: The adjustment formula of the current phase is: Among them, φ adjusted is the adjusted current phase, φ initial is the current phase before adjustment, Kq is the adjustment coefficient, Δθ is the amplitude difference between the active power and the target active power, θ acture is the current active power phase, θ target is the target active power phase.

7. The energy storage converter control method according to claim 1, characterized in that: The adaptively setting the parameters of the V / F controller based on the frequency reference value includes: The output frequency and voltage amplitude set point of the V / F controller are adaptively adjusted based on the grid voltage and the frequency reference value.

8. The energy storage converter control method according to claim 7, characterized in that: The method of adaptively adjusting the output frequency and voltage amplitude set point of the V / F controller based on the grid voltage and the frequency reference value comprises: Constructing a voltage output variation model of the energy storage converter according to the historical grid voltage; Calling the voltage output variation model to predict the future grid voltage, and adjusting the output frequency and voltage amplitude set point of the V / F controller based on the prediction result; The voltage output variation model is updated based on the grid voltage acquired in real time.

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