An adaptive power energy storage converter control method and system

Abstract

The application discloses a kind of self-adaptive power energy storage converter control method and system, this method can effectively solve the problem of overvoltage and under-voltage of grid-connected point and overcharge and overdischarge of energy storage battery by controlling the adaptive charge and discharge of energy storage battery.First, the grid voltage is sampled and the effective value is processed to obtain the grid voltage effective value feedback signal U gf_rms , and it is sent to the inverting input end of voltage error amplifier, and the grid voltage reference U ref Is sent to the non-inverting input end of voltage error amplifier.The output U e Of voltage error amplifier is obtained by positive and negative limiting link U e1 Is sent to one input end of multiplier.The state signal J of range determination is obtained by the state of charge signal Soc of energy storage battery, and the other input end of multiplier is sent.The output I ref Of multiplier is sent to the non-inverting input end and inverting input end of current regulator respectively with the charging current sampling signal I bf Of energy storage battery.The output of current regulator is used as modulation signal, and it is sent to PWM modulator.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage converter control, and particularly relates to an adaptive power energy storage converter control method and system. BACKGROUND

[0002] With the development of new energy layout in China, a series of distributed renewable energy power generation systems such as wind power generation and photovoltaic power generation are booming. According to the relevant policies such as the Opinions on Promoting the Healthy Development of Photovoltaic Industry, photovoltaic power generation should be developed in a scattered manner and mainly consumed in the vicinity. Therefore, the number and capacity of distributed photovoltaic power generation in the medium and low voltage distribution network are also rapidly increasing. Among them, due to the influence of weather factors, overvoltage or undervoltage of the grid voltage is the main factor limiting the capacity of photovoltaic access. Based on the demand of the majority of users for power quality of the distribution network, the overvoltage and undervoltage of the grid voltage of the photovoltaic inverter have become a problem that needs to be solved urgently.

[0003] Configuring an energy storage system is the most effective solution to this problem. The energy storage battery can not only solve the problem of voltage overrun and drop of the photovoltaic inverter grid connection point caused by the randomness of new energy, but also greatly improve the utilization rate of new energy and avoid the problem of wind or light abandonment. However, the introduction of the energy storage system makes the control of power transmission of the photovoltaic grid-connected system complex, especially the charging and discharging strategy of the energy storage battery system. The traditional energy storage converter control takes the DC bus voltage as the control target. This scheme cannot effectively solve the problem of overvoltage and undervoltage of the grid voltage, and the overdischarge and overcharge of the energy storage battery will cause energy waste and reduce the service life of the energy storage battery, affecting the interests of the distributed photovoltaic owners. Therefore, an adaptive power control method of energy storage converter is urgently needed, which can independently control the size of the charging and discharging current according to the high and low of the grid voltage, effectively suppress the problem of overvoltage and undervoltage of the grid, and independently set the battery charging and discharging range, greatly improving the service life of the battery. SUMMARY

[0004] The present application provides an adaptive power energy storage converter control method, which can independently control the size of the charging and discharging current according to the high and low of the grid voltage, effectively suppress the problem of overvoltage and undervoltage of the grid, and independently set the battery charging and discharging range, greatly improving the service life of the battery, based on which the present application further provides an adaptive power energy storage converter control system.

[0005] Technical scheme: According to the first aspect of the present application, an adaptive power energy storage converter control method is provided, which comprises the following steps:

[0006] S1, sampling the low-voltage distribution network voltage U g through the voltage sampling coefficient H gThe effective value U of the voltage sampled in the low-voltage distribution network is obtained through the calculation and processing of the RMS module. gf_rms ;

[0007] S2 will use the grid voltage reference U ref The effective value U of the voltage sampled from the low-voltage distribution network gf_rms The signals are fed into the non-inverting and inverting inputs of the voltage error amplifier, respectively, and the output is the voltage error signal U. e The limiting voltage error signal U is obtained through positive and negative limiting circuits. e1 ;

[0008] S3 detects the state of charge (Soc) of the energy storage battery, determines its range, and obtains the state signal J.

[0009] S4 will combine the status signal J with the limiting voltage error signal U. e1 The signals are fed into the two input terminals of the multiplier respectively to obtain the current reference signal I. ref ;

[0010] S5 will transfer the current reference signal I ref With the charging current I of the energy storage battery b Sampling signal I bf These are respectively used as the positive and negative inputs of the current regulator, and the output is a modulation signal; wherein, the sampling signal I bf It is the charging current I of the energy storage battery b Through the current sampling coefficient H i Later obtained;

[0011] S6 feeds the modulation signal generated by the current regulator to the PWM modulator to generate a corresponding control PWM signal, thereby completing the regulation and control of the bidirectional converter and realizing the adaptive charging and discharging control of the energy storage battery.

[0012] Furthermore, including:

[0013] The effective value U of the voltage sampling of the low-voltage distribution network gf_rms Represented as:

[0014]

[0015] Where N is the low-voltage distribution network voltage U g The number of sampling points within one power frequency cycle, with M power frequency cycles as the calculation limit, M≥2.

[0016] Furthermore, including:

[0017] In step S2, the limiting voltage error signal U is obtained through positive and negative limiting circuits. e1 ,include:

[0018] The amplitude voltage error signal U e1 The upper limit and the lower limit of U e1max , -U e1min The energy storage battery charging current I b The size limit and the current sampling coefficient H i The design of the current sampling coefficient H

[0019] When the energy storage battery is charged:

[0020] When the energy storage battery is discharged:

[0021] Further, comprising:

[0022] In the step S3, the Soc range is determined, and the specific determination method is:

[0023]

[0024] Wherein, Soc min And Soc max Are the minimum and maximum set values of Soc, which are used to avoid over-discharge and over-charge of the energy storage battery.

[0025] On the other hand, the application also provides an adaptive power energy storage converter control system, which is used to realize the adaptive power energy storage converter control method, and specifically comprises a grid-connected unit, an energy storage unit and a control unit, the output of the bidirectional converter of the grid-connected unit is connected to the energy storage unit, and the storage and release of electric energy are completed, and the control unit comprises a voltage error amplifier, a multiplier, a current regulator and a PWM modulator.

[0026] Wherein, the effective value of the low-voltage power distribution network voltage is processed to obtain a grid voltage effective value feedback signal, which is sent to the inverting input end of the voltage error amplifier, and the grid voltage reference is sent to the non-inverting input end of the voltage error amplifier, the output of the voltage error amplifier is sent to one input end of the multiplier through the positive and negative limiting link to obtain a limiting voltage error amplified signal.

[0027] At the same time, the state signal of the energy storage unit is determined to obtain a state signal, which is sent to the other input end of the multiplier, and the output of the multiplier and the charging current sampling signal of the energy storage unit are sent to the non-inverting input end and the inverting input end of the current regulator respectively, the output of the current regulator is sent to the PWM modulator as a modulation signal, and the corresponding control PWM signal is generated to complete the adjustment and control of the bidirectional converter, so as to realize the adaptive charging and discharging control of the energy storage battery.

[0028] Further, comprising:

[0029] The grid-connected unit comprises a photovoltaic array, a boost converter, an energy storage battery, a bidirectional converter, a grid-connected inverter and a filter.

[0030] The photovoltaic array is connected to the input end of the boost converter as an output end; the output end of the boost converter is connected to the input end of the grid-connected inverter and the input end of the bidirectional converter; the output end of the grid-connected inverter is connected to the filter, thereby completing the grid connection of photovoltaic power generation.

[0031] Further comprising:

[0032] The energy storage unit comprises an energy storage battery.

[0033] Advantages: Compared with the prior art, the present application has the following advantages:

[0034] (1) Low cost, only need to add voltage detection hardware of the grid-connected point;

[0035] (2) Simple implementation, only need to introduce the detection of the grid-connected point voltage into the loop control of the energy storage converter;

[0036] (3) Adaptive control, when the grid-connected point is overvoltage, the energy storage battery enters the charging mode, and the charging current will increase with the increase of the overvoltage, thereby effectively inhibiting the overvoltage; when the grid-connected point is under-voltage, the energy storage battery enters the discharging mode, and the discharging current will increase with the increase of the under-voltage, thereby effectively inhibiting the under-voltage.

[0037] (4) Self-setting battery state of charge, through the range determination of the state of charge, only when the battery is in the specified state, the charging and discharging operation can be carried out, avoiding overcharging and overdischarging of the battery, and effectively prolonging the service life of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The adaptive power energy storage converter control structure diagram described in the embodiment of the present application;

[0039] Figure 1 Main symbol name in the figure: H i Current sampling coefficient, H g Voltage sampling coefficient, RMS - effective value operation, Soc - energy storage battery state of charge, I b Energy storage battery charging current, I bf Energy storage battery charging current sampling value; J - energy storage battery state, U e Grid voltage error method value, U e1 Grid voltage error amplification limiting value, U g Grid voltage, U gf_rms— Grid voltage effective value, I ref — Energy storage battery charging current reference;

[0040] Figure 2 Waveform schematic diagram of the adaptive power energy storage converter control scheme described in the embodiments of the present application, wherein (a) is a grid overvoltage operating state diagram, (b) is a grid under-voltage operating state diagram, (c) is a state diagram in which Soc exceeds the upper limit, and (d) is a state diagram in which Soc is lower than the lower limit.

[0041] Figure 3 Flowchart of the adaptive power energy storage converter control method described in the embodiments of the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, and not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0043] It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0044] Embodiment 1

[0045] The present application proposes an adaptive power control method for an energy storage converter. When the grid voltage at the grid connection point of a photovoltaic inverter is too high, the energy storage battery is adaptively controlled to charge, thereby absorbing excess power and effectively suppressing the rise of the grid voltage. When the grid voltage at the grid connection point of a photovoltaic inverter is too low, the energy storage battery is adaptively controlled to discharge, thereby releasing power and effectively making up for the drop of the grid voltage. At the same time, in order to avoid overcharging or overdischarging of the energy storage battery, the present application can automatically set the charging and discharging upper limit of the energy storage battery Soc and the charging and discharging current, thereby greatly improving the operating life of the energy storage battery.

[0046] As shown in Figure 3 The present application provides an adaptive power energy storage converter control method, which comprises the following steps:

[0047] S1 obtains a low-voltage power grid voltage U g After being processed by a voltage sampling coefficient H g and an effective value module RMS, an effective value U gf_rms of the low-voltage power grid voltage sample is obtained.

[0048] In this embodiment, the effective value module RMS is not limited and can be an effective value chip or calculated in a program. If calculated in a program, the calculation formula is:

[0049]

[0050] wherein, N is the low-voltage distribution network voltage U g The number of sampling points in one power frequency cycle, and M power frequency cycles are used as the calculation limit, M≥2, the purpose is to improve the stability of control, because when the system is disturbed, the smaller M is, the greater the change of U gf_ms The change amount will lead to a large system adjustment amount, so that the system output is more unstable, therefore, the optimal selection is M=3, therefore, is expressed as:

[0051]

[0052] wherein, N is the low-voltage distribution network voltage U g The number of sampling points in one power frequency cycle, and M power frequency cycles are used as the calculation limit, M≥2, the purpose is to improve the stability of control, because when the system is disturbed, the smaller M is, the greater the change of U

[0053] S2 sends the grid voltage reference U ref and the effective value of the low-voltage distribution network voltage sample U gf_rms to the same phase and opposite phase terminals of the voltage error amplifier respectively, and outputs to obtain the voltage error signal U e , and through the positive and negative limiting amplitude link to obtain the limiting amplitude voltage error signal U e1 .

[0054] The specific model of the voltage error amplifier is not limited in this embodiment, which can be linear or nonlinear.

[0055] S3 detects the state of charge Soc of the energy storage battery, and performs range determination to obtain a state signal J.

[0056] Specifically, the Soc range determination in step S3 is specifically determined by the following method:

[0057]

[0058] wherein, Soc min and Soc max are the minimum and maximum set values of Soc, respectively, which are used to avoid over-discharge and over-charge of the energy storage battery.

[0059] S4 sends the state signal J and the limiting amplitude voltage error signal U e1 to the two input terminals of the multiplier respectively, to obtain the current reference signal I ref .

[0060] S5 sends the current reference signal I ref and the sampling signal I b of the charging current I of the energy storage battery to the multiplier, to obtain the charging current I .bf These are respectively used as the positive and negative inputs of the current regulator, and the output is a modulation signal; wherein, the sampling signal I bf It is the charging current I of the energy storage battery b Through the current sampling coefficient H i It was obtained later.

[0061] In this embodiment, in order to achieve autonomous setting of charge and discharge thresholds and avoid overcharging and over-discharging of the energy storage battery, the following settings are required:

[0062] The upper limit of the output voltage U of the positive and negative limiting circuit in step S2 e1max With lower limit -U e1min The energy storage battery charging current I in step S5 b Size limitations and sampling coefficient H i The design should conform to the following relationships:

[0063]

[0064] This embodiment does not impose upper or lower limits; these limits can be determined based on the maximum charge / discharge current to be designed. Specifically, this is achieved through a reasonable current sampling coefficient H. i With the upper limit U of the positive and negative limiting links e1max With lower limit -U e1min The design allows users to set the maximum charging and discharging current independently.

[0065] S6 feeds the modulation signal generated by the current regulator to the PWM modulator to generate a corresponding control PWM signal, thereby completing the regulation and control of the bidirectional converter and realizing the adaptive charging and discharging control of the energy storage battery.

[0066] Therefore, this control method can effectively solve the problems of excessively high and low grid connection voltage, and at the same time, it can effectively prevent overcharging and over-discharging of energy storage batteries, thereby improving the stability of grid voltage and the lifespan of energy storage batteries.

[0067] When the grid connection point voltage of the photovoltaic inverter is too high, the voltage error amplifier will output a negative value with an upper limit. The current of the energy storage battery tracks this negative value, causing the energy storage battery to charge. The maximum charging current is limited by the upper limit of this negative value. When the grid connection point voltage of the photovoltaic inverter is too low, the voltage error amplifier will output a positive value with an upper limit. The current of the energy storage battery tracks this positive value, causing the energy storage battery to discharge. The maximum discharging current is limited by the upper limit of this positive value. At the same time, in order to avoid overcharging or over-discharging of the energy storage battery, this invention uses a State of Charge (SOC) range determination step. When the SOC exceeds the specified range, the current reference of the energy storage battery is set to 0, that is, charging and discharging are no longer carried out. This effectively avoids overcharging and over-discharging of the energy storage battery and greatly improves the lifespan of the energy storage battery.

[0068] The embodiment does not limit the specific model of the current regulator, which can be a P controller or a PI controller.

[0069] In another aspect, the application also provides a self-adaptive power energy storage converter control system for implementing the method of embodiment 1, which specifically comprises a photovoltaic array, a boost converter, an energy storage battery, a bidirectional converter, a grid-connected inverter, a filter, a voltage error amplifier, a multiplier, a current regulator, and a PWM modulator.

[0070] The photovoltaic array is connected to the input end of the boost converter as the output end;

[0071] The output end of the boost converter is connected to the input end of the grid-connected inverter and the input end of the bidirectional converter; the output end of the grid-connected inverter is connected to the filter to complete the grid connection of photovoltaic power generation;

[0072] The output end of the bidirectional converter is connected to the energy storage battery to complete the storage and release of electric energy.

[0073] The grid voltage effective value feedback signal is obtained by sampling and effective value processing of the grid point voltage and is sent to the inverting input end of the voltage error amplifier; the grid voltage reference is sent to the non-inverting input end of the voltage error amplifier. The output of the voltage error amplifier is sent to one input end of the multiplier through the positive and negative limiting link to obtain the limiting voltage error amplified signal.

[0074] The state signal is obtained by range determination of the state of charge signal of the energy storage battery and is sent to the other input end of the multiplier. The output of the multiplier and the charging current sampling signal of the energy storage battery are sent to the non-inverting input end and the inverting input end of the current regulator, respectively. The output of the current regulator is sent to the PWM modulator as the modulation signal, thereby realizing the self-adaptive charging and discharging of the energy storage battery according to the high and low of the grid point voltage and effectively solving the problems of excessively high and low grid point voltage.

[0075] The specific working principle of the application is described below mainly based on Figure 1 The corresponding circuit key waveforms are shown in Figure 2 .

[0076] Firstly, the application samples the grid point voltage to obtain the grid voltage effective value feedback signal U gf_rms , which is sent to the inverting input end of the voltage error amplifier; the grid voltage reference U ref is sent to the non-inverting input end of the voltage error amplifier. The output U e of the voltage error amplifier is sent to one input end of the multiplier through the positive and negative limiting link to obtain U e1The signal is fed into one input terminal of the multiplier. The state-of-charge signal Soc of the energy storage battery is range-determined to obtain the state signal J, which is then fed into the other input terminal of the multiplier. The output I of the multiplier is... ref The charging current sampling signal I of the energy storage battery bf The signals are fed into the non-inverting and inverting inputs of the current regulator, respectively. The output of the current regulator serves as a modulation signal, which is then fed into the PWM modulator. By controlling the bidirectional converter, the energy storage battery can adaptively charge and discharge according to the grid connection point voltage, effectively solving the problems of excessively high or low grid connection point voltage.

[0077] This application effectively solves the problem of grid voltage instability caused by the integration of a large number of new energy sources into the grid. It not only prevents grid voltage over-limits but also prevents grid voltage drops, greatly improving grid voltage stability. Furthermore, this application effectively solves the overcharging and over-discharging problems of energy storage batteries in current energy storage systems. This application allows for the independent setting of charge and discharge thresholds, avoiding overcharging and over-discharging of energy storage batteries, significantly extending their service life and reducing their operation and maintenance costs.

[0078] like Figure 2 In the simulation shown, the upper limit of the Soc was set to 80%, and the lower limit to 20%. Figures a, b, c, and d show the simulation waveforms corresponding to the initial Soc of the battery being 50%, 50%, 84.5%, and 12%, respectively.

[0079] from Figure 2 As shown in waveform (a), when the effective value of the grid connection point voltage exceeds 220V (i.e., it is in an overvoltage state), it can be seen that the energy storage battery is in a charging state, absorbing excess energy and suppressing the grid voltage from rising further. Moreover, it can be seen from the waveform shape that the more the grid voltage exceeds 220V, the greater the charging current.

[0080] from Figure 2 As shown in waveform (b), when the effective value of the grid connection point voltage is lower than 220V (i.e., undervoltage), the energy storage battery is in a discharging state, releasing electrical energy to compensate the grid and suppress further voltage drop. Moreover, the shape of the waveform shows that the lower the grid voltage is than 220V, the greater the discharge current.

[0081] from Figure 2 As can be seen in (c), when the Soc exceeds the upper limit, the charging and discharging current of the energy storage battery remains at around 0, and it stops charging to avoid overcharging the battery.

[0082] from Figure 2 As can be seen from (d) in the figure, when the Soc is below the lower limit, the charging and discharging current of the energy storage battery is kept at around 0, and it stops discharging to avoid over-discharging.

[0083] As can be seen from the above, the control method can realize adaptive charging and discharging control of the energy storage battery when in operation: when the grid voltage is higher than the reference value, the energy storage battery enters the charging mode, and the charging current increases with the increase of the grid voltage, thereby absorbing excess power to inhibit the rise of the grid voltage; when the grid voltage is lower than the reference value, the energy storage battery enters the discharging mode, and the discharging current increases with the decrease of the grid voltage, thereby releasing sufficient power to inhibit the drop of the grid voltage. Therefore, when the Soc of the energy storage battery is not within the set range, the method can prevent the battery from continuing to charge or discharge, thereby avoiding overcharging and overdischarging of the battery.

[0084] It should be noted that the storage medium provided by the embodiments of the present application is a storage medium used to implement the method of the embodiments of the present application. Therefore, based on the method introduced in the embodiments of the present application, a person skilled in the art can understand the specific structure and modifications of the storage medium, and therefore will not be described here. Any storage medium used by the method of the embodiments of the present application belongs to the scope of the present application.

[0085] Those skilled in the art will appreciate that embodiments of the present application can be provided as methods, systems or computer program products. Therefore, the present application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can be in the form of a computer program product implemented on one or more computer usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0086] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system) and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams can be implemented by computer program instructions, and the combination of flows and / or blocks in the flowcharts and / or block diagrams. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 The means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 The means for implementing the functions specified in the flowcharts and / or block diagrams.

[0087] These computer program instructions can also be stored in a computer readable storage medium which can guide the computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer readable storage medium produce a product including instruction means, which implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1the function specified in the one or more blocks.

[0088] These computer program instructions can also be loaded into computer or other programmable data processing devices, so that a series of operation steps are performed on the computer or other programmable devices to generate computer-implemented processes, thus the instructions executed on the computer or other programmable devices provide a process for implementing the flow Figure 1 the flow or flows and / or blocks Figure 1 the steps of the function specified in the one or more blocks.

[0089] It is noted that in the claims the reference signs placed between parentheses shall not be construed as limiting the claim. The word 'comprising' does not exclude the presence of elements or steps not listed in a claim. The word 'a' or 'an' preceding an element does not exclude the presence of a plurality of such elements. The application can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unitary claim, several of the apparatuses mentioned in the groups of apparatuses can be embodied by one and the same item of hardware. The use of the words 'first','second', and 'third', etc. do not imply any order. These words are used to name the circumstances in which the embodiments can occur.

[0090] Although the preferred embodiments of the application have been described, those skilled in the art will recognize that many modifications and variations of the described implementation can be made without departing from the spirit or scope of the application. Accordingly, it is intended that all such modifications and variations be included within the scope of the following claims and the scope of the application.

[0091] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

[0092] The above merely preferred embodiments of the present application and are not therefore to be taken as limiting the scope of the patent, the scope of patent being limited solely by the claims.

Claims

1. A method of adaptive power energy storage converter control, the method comprising: The method comprises the following steps: S1 obtains the low-voltage distribution network voltage U g through a voltage sampling coefficient H g and the operation processing of the effective value module RMS, to obtain the effective value U gf_rms of the low-voltage distribution network voltage sampling S2 will grid voltage reference U ref The effective value of the low-voltage distribution network voltage sampled U gf_rms The in-phase terminal and the anti-phase terminal of the voltage error amplifier are respectively sent into, and the output voltage error signal U e The limiting voltage error signal U e1 is obtained through the positive and negative limiting links. S3, detecting the state of charge Soc of the energy storage battery and performing range determination to obtain a state signal J; S4 compares the state signal J with the clipped voltage error signal U e1 The two inputs of the multiplier are fed with the current reference signal I ref ; S5 will current reference signal I ref with the charging current I b of the energy storage battery bf , respectively as the positive input and the negative input of the current regulator, output modulation signal; wherein the sampling signal I bf is the charging current I b of the energy storage battery i after the current sampling coefficient H S6, feeding the modulation signal generated by the current regulator into a PWM modulator to generate a corresponding control PWM signal, completing the regulation and control of the bidirectional converter, thereby realizing adaptive charging and discharging control of the energy storage battery; In the step S2, the limiting voltage error signal U is obtained through the positive and negative limiting link e1 comprising: The amplitude-limited voltage error signal U e1 The upper and lower limits of U e1max , -U e1min The energy storage battery charging current I b The design of the current sampling coefficient H i The maximum current of the charging and discharging is set automatically according to the following relationship: The energy storage battery The energy storage battery In the step S3, the Soc range is determined, and the specific determination method is as follows: Wherein, Soc min Soc max are minimum and maximum set values of Soc respectively, which are used to avoid over-discharge and over-charge of the energy storage battery.

2. The adaptive power energy storage converter control method of claim 1, wherein, The effective value U of the low-voltage distribution network voltage sampling gf_rms is expressed as: Wherein, N is the low-voltage distribution network voltage U g The number of sampling points in one power frequency cycle, and M power frequency cycles are used as the calculation limit, .

3. An adaptive power energy storage converter control system, characterized by, The system is used to realize the adaptive power energy storage converter control method according to claim 1 or 2, and specifically comprises a grid-connected unit, an energy storage unit and a control unit, the bidirectional converter output of the grid-connected unit is connected to the energy storage unit, completing the storage and release of electric energy, and the control unit comprises a voltage error amplifier, a multiplier, a current regulator and a PWM modulator; The grid voltage effective value feedback signal is obtained by sampling the low-voltage power distribution network voltage for effective value processing, and is sent to the inverting input end of the voltage error amplifier, and the grid voltage reference is sent to the non-inverting input end of the voltage error amplifier, the output of the voltage error amplifier is sent to one input end of the multiplier through a positive and negative limiting link to obtain a limiting voltage error amplification signal, and the other input end of the multiplier is connected to the state signal of the energy storage unit. At the same time, the state signal of the energy storage unit is subjected to range determination to obtain a state signal, and is sent to the other input end of the multiplier, the output of the multiplier and the charging current sampling signal of the energy storage unit are respectively sent to the non-inverting input end and the inverting input end of the current regulator, the output of the current regulator is taken as a modulation signal and is sent to the PWM modulator to generate a corresponding control PWM signal, completing the regulation and control of the bidirectional converter, thereby realizing adaptive charging and discharging control of the energy storage battery.

4. The adaptive power energy storage converter control system of claim 3, wherein, The grid-connected unit comprises a photovoltaic array, a boost converter, an energy storage battery, a bidirectional converter, a grid-connected inverter and a filter. The photovoltaic array is taken as an output end and is connected to the input end of the boost converter; the output end of the boost converter is connected to the input end of the grid-connected inverter and the input end of the bidirectional converter; the output end of the grid-connected inverter is connected to the filter, completing the grid connection of photovoltaic power generation.

5. The adaptive power energy storage converter control system of claim 3, wherein, The energy storage unit comprises an energy storage battery.

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