A dynamic control method, device and equipment of a photovoltaic inverter

Abstract

The present disclosure provides a dynamic control method, device and equipment of a photovoltaic inverter, relating to the technical field of photovoltaic power generation. The method adjusts a first basic electricity price threshold according to the relationship between the used electricity and the total electricity quota within a preset statistical period to obtain a first electricity price threshold, wherein the smaller the difference between the total electricity quota and the used electricity and the total electricity quota, the higher the first electricity price threshold. The second basic electricity price threshold is adjusted according to the electricity price fluctuation rate correction factor of the current transaction period to obtain a second electricity price threshold. According to the relationship between the real-time electricity price and the first electricity price threshold and the second electricity price threshold, the output power of the photovoltaic inverter is controlled to be less than or equal to the local load power, to be output according to the target output power corresponding to the minimum value between the local load power and the maximum available power, or to be output according to the maximum available power under the current working condition in different electricity price intervals, thereby improving the adaptability of the output power control of the photovoltaic inverter to the dynamically changing electricity price.

Description

Technical Field

[0001] This disclosure relates to the field of photovoltaic power generation technology, and in particular to a dynamic control method, device and equipment for a photovoltaic inverter. Background Technology

[0002] In scenarios where photovoltaic (PV) power generation systems participate in electricity market transactions, the electricity generated by the PV system can be settled based on the electricity price for the corresponding trading period. Because electricity prices in the electricity market are influenced by factors such as electricity supply and demand, different trading periods have different prices, and negative prices may even occur during some trading periods.

[0003] In related technologies, photovoltaic inverters typically use maximum power point tracking (MPPT) to control the output power of photovoltaic power generation systems. When it is necessary to limit the output power of a photovoltaic power generation system, a fixed power limit can be preset, and the photovoltaic inverter can be controlled to output power according to that limit.

[0004] However, since electricity prices can change dynamically with the trading period, photovoltaic inverters that continuously output the maximum available power under the current operating conditions or output the fixed power limit set in advance cannot adapt to changes in electricity prices in a timely manner; when using the method of manually setting the power limit, it is also necessary to reset it according to changes in electricity prices.

[0005] Therefore, how to improve the adaptability of photovoltaic inverter output power control to dynamically changing electricity prices has become a technical problem that urgently needs to be solved by those skilled in the art.

[0006] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this disclosure is to provide a dynamic control method, apparatus, and device for a photovoltaic inverter, so as to improve the adaptability of the output power control of the photovoltaic inverter to dynamically changing electricity prices.

[0008] According to a first aspect of the embodiments of this specification, a dynamic control method for a photovoltaic inverter is provided, comprising: Based on the relationship between the used electricity and the total electricity quota within a preset statistical period, a preset first basic electricity price threshold is adjusted to obtain a first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold. Based on the electricity price volatility correction factor corresponding to the current trading period, the preset second basic electricity price threshold is adjusted to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold; When the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold, the output power of the photovoltaic inverter is controlled to be less than or equal to the local load power. When the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition is determined as the target output power, and the photovoltaic inverter is controlled to output according to the target output power; When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition.

[0009] In one exemplary embodiment of this application, adjusting a preset first base electricity price threshold based on the relationship between used electricity and total electricity quota within a preset statistical period to obtain a first electricity price threshold includes: Determine the difference between the total available battery capacity and the amount of battery power already used; When the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first basic electricity price threshold is reduced based on the difference between the ratio and the first proportional threshold to obtain the first electricity price threshold. When the ratio of the difference to the total electricity allowance is less than the second proportional threshold, the first basic electricity price threshold is increased based on the difference between the second proportional threshold and the ratio to obtain the first electricity price threshold. Wherein, the first ratio threshold is greater than the second ratio threshold.

[0010] In one exemplary embodiment of this application, when the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first electricity price threshold is determined by the following formula: ; When the ratio of the difference to the total electricity allowance is less than the second proportional threshold, the first electricity price threshold is determined by the following formula: ; in, This represents the first electricity price threshold; This represents the first basic electricity price threshold; This represents the second basic electricity price threshold; This represents the ratio of the difference to the total battery capacity. This represents the first proportional threshold; This represents the second proportional threshold; and These represent the first and second corrected gain coefficients, respectively. , .

[0011] In one exemplary embodiment of this application, adjusting the preset second base electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold includes: The second electricity price threshold is determined using the following formula: ; in, This represents the second electricity price threshold; This represents the second basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the second base electricity price threshold.

[0012] In one exemplary embodiment of this application, the photovoltaic power generation system in which the photovoltaic inverter is located includes an energy storage device, and the method further includes: Based on the electricity price volatility correction factor corresponding to the current trading period, the preset third basic electricity price threshold is adjusted to obtain the third electricity price threshold; the third electricity price threshold is greater than the second electricity price threshold. When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, controlling the photovoltaic inverter to output according to the maximum available power corresponding to the current operating condition includes: When the real-time electricity price is greater than or equal to the second electricity price threshold and less than the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to stop charging and discharging. When the real-time electricity price is greater than or equal to the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to discharge at the maximum discharge power.

[0013] In one exemplary embodiment of this application, the third electricity price threshold is determined by the following formula: ; in, This represents the third electricity price threshold; This represents the third basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the third basic electricity price threshold.

[0014] In one exemplary embodiment of this application, the photovoltaic inverter is connected to at least one photovoltaic string, and controlling the photovoltaic inverter to output power according to the target output power includes: The power-voltage characteristic curve of the photovoltaic string is corrected based on the current ambient temperature and irradiance. Based on the target output power, determine the target operating voltage corresponding to the target output power on the corrected power-voltage characteristic curve; Based on the target operating voltage, the photovoltaic inverter is subjected to non-maximum power point tracking control so that the output power of the photovoltaic inverter reaches the target output power.

[0015] In one exemplary embodiment of this application, the photovoltaic inverter is connected to multiple photovoltaic strings, each photovoltaic string having a corresponding power allocation value, wherein the sum of the power allocation values ​​corresponding to each photovoltaic string is equal to the target output power; Controlling the photovoltaic inverter to output power according to the target output power includes: The irradiance and temperature parameters of each photovoltaic string are obtained respectively, and the available power of the corresponding photovoltaic string is determined based on the irradiance and temperature parameters of each photovoltaic string. When the available power of the photovoltaic string is greater than the corresponding power allocation value, the operating point voltage of the photovoltaic string is determined according to the power allocation value, and the operating voltage of the photovoltaic string is adjusted to the operating point voltage so that the output power of the photovoltaic string is reduced to the power allocation value. When the available power of the photovoltaic string is less than the corresponding power allocation value, the photovoltaic string is controlled to output according to the available power.

[0016] According to a second aspect of the embodiments of this specification, a dynamic control device for a photovoltaic inverter is provided, comprising: The first threshold adjustment module is used to adjust the preset first basic electricity price threshold according to the relationship between the used electricity and the total electricity quota within the preset statistical period to obtain the first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold. The second threshold adjustment module is used to adjust the preset second basic electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold. The first output control module is used to control the output power of the photovoltaic inverter to be less than or equal to the local load power when the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold. The second output control module is used to determine the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition as the target output power when the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, and to control the photovoltaic inverter to output according to the target output power. The third output control module is used to control the photovoltaic inverter to output the maximum available power corresponding to the current operating condition when the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold.

[0017] According to a third aspect of the embodiments of this specification, an electronic device is provided, comprising: Memory, used to store computer programs; A processor, connected to the memory, is used to implement the above-described dynamic control method for the photovoltaic inverter when executing the computer program.

[0018] The technical solutions provided in this disclosure may have the following beneficial effects: This application adjusts a first basic electricity price threshold based on the relationship between used electricity and total electricity quota within a preset statistical period, and adjusts a second basic electricity price threshold based on the electricity price volatility correction factor corresponding to the current trading period. This allows the first electricity price threshold to change with the usage of the electricity quota, and the second electricity price threshold to change with the electricity price fluctuations during the current trading period. Furthermore, based on the relationship between the real-time electricity price and the first and second electricity price thresholds, the application limits the output power of the photovoltaic inverter in different electricity price ranges, controls the photovoltaic inverter to output at a target output power, or controls the photovoltaic inverter to output at the maximum available power corresponding to the current operating conditions. This allows the output power of the photovoltaic inverter to be adjusted in conjunction with the usage of the electricity quota, electricity price fluctuations, and the electricity price range in which the real-time electricity price is located. This avoids the difficulty in responding to price changes in a timely manner when using a fixed electricity price to determine boundaries or a fixed power limit, and improves the adaptability of the photovoltaic inverter's output power control to dynamically changing electricity prices.

[0019] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this specification. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this specification and, together with the description, serve to explain the principles of this specification.

[0021] Figure 1 This is a schematic diagram of output control corresponding to different real-time electricity price ranges provided in the embodiments of this application.

[0022] Figure 2 A flowchart illustrating the dynamic control method for a photovoltaic inverter provided in this application embodiment.

[0023] Figure 3 This is a schematic diagram illustrating the operating point adjustment principle of the power-voltage characteristic curve of a photovoltaic string provided in an embodiment of this application.

[0024] Figure 4 This is a schematic diagram of power control for multiple photovoltaic strings provided in an embodiment of this application.

[0025] Figure 5 This is a structural diagram of the dynamic control device for a photovoltaic inverter provided in an embodiment of this application.

[0026] Figure 6 This is a structural diagram of an electronic device provided in an embodiment of this application.

[0027] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts. Detailed Implementation

[0028] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this specification. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this specification as detailed in the appended claims.

[0029] The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of this specification. The singular forms “a,” “the,” and “the” as used in this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0030] It should be understood that although the terms first, second, third, etc., may be used in this specification to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this specification, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0031] This application provides a dynamic control method, apparatus, and device for a photovoltaic inverter, which will be described in detail in the following embodiments.

[0032] To facilitate understanding of the dynamic control method for photovoltaic inverters provided in this application, we will first introduce the method in conjunction with its application scenarios.

[0033] In one application scenario of this application, a photovoltaic power generation system participates in electricity market transactions. During the electricity market transaction process, the real-time electricity price changes with the trading period, and negative electricity prices may occur during some trading periods. When the real-time electricity price is low, it means that the local power supply demand is low. If the photovoltaic inverter still outputs the maximum available power corresponding to the current operating conditions, and the local load cannot use all the photovoltaic power, the portion of the electricity exceeding the local load power will still be output to the grid. Therefore, it is necessary to limit the output power of the photovoltaic inverter.

[0034] As real-time electricity prices rise, the necessity to limit the output power of photovoltaic (PV) inverters decreases accordingly. When real-time electricity prices reach a high level, PV inverters can output the maximum available power corresponding to the current operating conditions. Therefore, the control requirements for the output power of PV inverters differ under different electricity price levels. In this application embodiment, multiple electricity price thresholds are set, and the output power of the PV inverter is controlled according to the relationship between the real-time electricity price and each electricity price threshold.

[0035] Please refer to Figure 1 , Figure 1 This is a schematic diagram of output control corresponding to different real-time electricity price ranges provided in the embodiments of this application.

[0036] like Figure 1 As shown, the horizontal axis represents the real-time electricity price corresponding to the current trading period. The real-time electricity price passes through the first electricity price threshold sequentially from low to high. Second electricity price threshold and the third electricity price threshold Among them, the first electricity price threshold Second electricity price threshold Used to determine the output power of a photovoltaic inverter, and a third electricity price threshold. When a photovoltaic power generation system is connected to an energy storage device, the discharge state of the energy storage device can be further determined.

[0037] When the real-time electricity price is less than the first electricity price threshold When the real-time electricity price is in a low range, the output power of the photovoltaic inverter can be limited, so that the output power of the photovoltaic inverter is less than or equal to the local load power.

[0038] When the real-time electricity price is greater than or equal to the first electricity price threshold And less than the second electricity price threshold When the target output power is less than the maximum available power of the photovoltaic inverter under the current operating conditions, the photovoltaic inverter can be controlled to output power according to the target output power. When the target output power is less than the maximum available power of the photovoltaic inverter under the current operating conditions, the output power of the photovoltaic inverter can be adjusted to reach the target output power by adjusting the operating voltage of the photovoltaic string.

[0039] When the real-time electricity price is greater than or equal to the second electricity price threshold At this time, the photovoltaic inverter can be controlled to output the maximum available power corresponding to the current operating conditions. Therefore, as the real-time electricity price moves from a lower price range to a higher price range, the output power of the photovoltaic inverter can change accordingly.

[0040] When a photovoltaic power generation system is connected to an energy storage device, and the real-time electricity price is greater than or equal to the second electricity price threshold... And less than the third electricity price threshold When the photovoltaic inverter outputs the maximum available power corresponding to the current operating conditions, the energy storage device stops charging and discharging; when the real-time electricity price is greater than or equal to the third electricity price threshold... At this time, the photovoltaic inverter continues to output the maximum available power corresponding to the current operating conditions, and controls the energy storage device to discharge at the maximum discharge power.

[0041] It should be noted that, Figure 1 This mainly illustrates the correspondence between real-time electricity prices and different output control states. The methods for determining the first, second, and third electricity price thresholds, as well as the specific output control process of the photovoltaic inverter under each electricity price range, will be further explained in the following embodiments.

[0042] This application also provides a dynamic control method for a photovoltaic inverter. Please refer to [link / reference]. Figure 2 , Figure 2 A flowchart illustrating the dynamic control method for a photovoltaic inverter provided in this application embodiment.

[0043] like Figure 2 As shown, the dynamic control method of this photovoltaic inverter includes the following steps S201 to S205: S201, Based on the relationship between the used electricity and the total electricity quota within the preset statistical period, the preset first basic electricity price threshold is adjusted to obtain the first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold.

[0044] The preset statistical period refers to the time range used to statistically analyze the total electricity consumption quota and its usage. The preset statistical period can be determined based on the statistical period corresponding to the total electricity consumption quota. For example, if the total electricity consumption quota is statistically analyzed monthly, the preset statistical period can be one month.

[0045] Total electricity quota refers to the total amount of electricity quota within a preset statistical period, used to limit the total electricity that can be included in the corresponding electricity quota within the preset statistical period. Correspondingly, used electricity refers to the amount of electricity that has been included in the total electricity quota usage within the preset statistical period up to the current moment.

[0046] The first basic electricity price threshold refers to the pre-set electricity price parameter used to provide an initial electricity price basis for determining the first electricity price threshold. The first electricity price threshold is an electricity price threshold obtained by adjusting the first basic electricity price threshold and is used to compare with the real-time electricity price corresponding to the current trading period in subsequent steps.

[0047] Specifically, when setting the first basic electricity price threshold, it has not yet been adjusted based on the changes in the amount of electricity used relative to the total electricity quota within the current preset statistical period. Therefore, the first basic electricity price threshold does not yet reflect the actual usage of the total electricity quota within the current preset statistical period. As the photovoltaic power generation system continues to operate, the amount of electricity used gradually changes, and the difference between the total electricity quota and the amount of electricity used, as well as the ratio of this difference to the total electricity quota, also changes accordingly. If the first basic electricity price threshold is always used as a fixed benchmark for real-time electricity prices, the judgment boundary used to distinguish different electricity price ranges cannot change accordingly with the changes in the aforementioned electricity usage, which may cause the subsequent output control of the photovoltaic inverter to be unable to adapt to the electricity usage within the current preset statistical period.

[0048] Therefore, during the operation of the photovoltaic power generation system, the first basic electricity price threshold can be adjusted based on the relationship between the used electricity and the total electricity quota within a preset statistical period to obtain the first electricity price threshold. Specifically, as the used electricity increases, the difference between the total electricity quota and the used electricity decreases, and the ratio of this difference to the total electricity quota decreases accordingly, thus increasing the first electricity price threshold. This allows the electricity price judgment boundary used for subsequent comparison with the real-time electricity price to change with the electricity usage within the current preset statistical period, thereby providing a corresponding judgment basis for subsequent control of the photovoltaic inverter output based on the real-time electricity price.

[0049] In some embodiments, the proportion of the unused portion of the total electricity allowance can be determined based on the total electricity allowance and the electricity used, thereby quantifying the relationship between the electricity used and the total electricity allowance within a preset statistical period.

[0050] Specifically, the difference between the total electricity allowance and the electricity used can be determined first, and then the ratio of this difference to the total electricity allowance can be determined using the following formula (1): (1); in, Indicates the total battery capacity; Indicates the amount of electricity used; This represents the ratio of the difference between the total available battery capacity and the amount of battery used to the total available battery capacity.

[0051] After determining the ratio R, the first base electricity price threshold can be adjusted based on R. Specifically, the ratio R represents the proportion of unused electricity quota within the total electricity quota during a preset statistical period. As used electricity increases, the ratio R decreases, indicating that the proportion of unused electricity quota decreases accordingly. At this time, by increasing the first electricity price threshold, the electricity price benchmark used for subsequent real-time electricity price determination can be changed accordingly, making the electricity price benchmark match the current electricity quota usage. Conversely, when the ratio R increases, it indicates that the proportion of unused electricity quota increases, and the first electricity price threshold can be decreased.

[0052] Therefore, the first electricity price threshold can be changed according to the usage of electricity quota within a preset statistical period, so that the output of the photovoltaic inverter can be controlled according to the relationship between the real-time electricity price corresponding to the current trading period and the first electricity price threshold.

[0053] In some embodiments, the above-described S201 can be implemented in the following manner: The difference between the total electricity allowance and the electricity used is determined; when the ratio of this difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first basic electricity price threshold is reduced based on the difference between this ratio and the first proportional threshold to obtain a first electricity price threshold; when the ratio of this difference to the total electricity allowance is less than a second proportional threshold, the first basic electricity price threshold is increased based on the difference between the second proportional threshold and this ratio to obtain a first electricity price threshold; wherein, the first proportional threshold is greater than the second proportional threshold.

[0054] The first proportional threshold and the second proportional threshold are both pre-set proportional parameters for the ratio R, used to determine the adjustment method used when adjusting the first basic electricity price threshold.

[0055] Specifically, when the ratio R is greater than or equal to a first proportional threshold, the first base electricity price threshold can be reduced based on the difference between the ratio R and the first proportional threshold; when the ratio R is less than a second proportional threshold, the first base electricity price threshold can be increased based on the difference between the second proportional threshold and the ratio R. The difference between the ratio R and the corresponding proportional threshold characterizes the degree of deviation of the ratio R from that threshold; the larger the difference, the greater the adjustment range corresponding to the first base electricity price threshold.

[0056] In some embodiments, in order to further determine the specific adjustment amount of the first base electricity price threshold, the first electricity price threshold can be calculated based on the ratio R, the corresponding proportional threshold, and the correction gain coefficient.

[0057] Wherein, when the ratio of the difference between the total electricity allowance and the electricity used to the total electricity allowance is greater than or equal to the first proportional threshold, the first electricity price threshold can be determined by the following formula (2): (2); When the ratio of the difference between the total electricity allowance and the electricity used to the total electricity allowance is less than the second proportional threshold, the first electricity price threshold can be determined by the following formula (3): (3); in, Indicates the first electricity price threshold; This indicates the first basic electricity price threshold; This indicates the second basic electricity price threshold; This represents the ratio of the difference between the total available battery capacity and the amount of battery used to the total available battery capacity. Indicates the first proportional threshold; Indicates the second proportional threshold; and These represent the first and second corrected gain coefficients, respectively. , .

[0058] For formula (2), when the ratio R equals the first proportional threshold hour, The value is 0, at which point the first electricity price threshold is reached. Equal to the first basic electricity price threshold As the ratio R increases, If the first base electricity price threshold is increased, while other parameters remain unchanged, the reduction in the first base electricity price threshold will increase accordingly, and the resulting first electricity price threshold will decrease accordingly.

[0059] For formula (3), when the ratio R is less than the second proportional threshold As the ratio R decreases, If the first base electricity price threshold is increased, while other parameters remain unchanged, the increase in the first electricity price threshold will be correspondingly increased, and the resulting first electricity price threshold will be correspondingly increased.

[0060] Through the above calculations, the change in the ratio R relative to the corresponding proportional threshold can be converted into a specific adjustment amount for the first basic electricity price threshold, thereby obtaining the first electricity price threshold corresponding to the electricity quota usage within the preset statistical period. This allows for subsequent control of the photovoltaic inverter output based on the relationship between the real-time electricity price corresponding to the current trading period and the first electricity price threshold.

[0061] S202, adjust the preset second basic electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold.

[0062] Similar to the first basic electricity price threshold, the second basic electricity price threshold is also a pre-set electricity price parameter used to provide an initial electricity price basis for determining the second electricity price threshold. In this embodiment, the second basic electricity price threshold is greater than the first basic electricity price threshold, so that the two form an initial electricity price judgment benchmark with a magnitude relationship. After adjusting the first and second basic electricity price thresholds respectively, the resulting second electricity price threshold is greater than the first electricity price threshold, thereby forming two different electricity price judgment boundaries. This facilitates the subsequent determination of the electricity price range of the real-time electricity price based on the relationship between the real-time electricity price corresponding to the current trading period and the first and second electricity price thresholds.

[0063] Specifically, electricity price changes may vary across different trading periods. If only a pre-set second basic electricity price threshold is used as the benchmark for price judgment, it will be difficult to reflect the electricity price fluctuations during the current trading period. Therefore, the second basic electricity price threshold can be adjusted according to the electricity price volatility correction factor for the current trading period, so that the obtained second electricity price threshold can be adjusted accordingly with the electricity price fluctuations during the current trading period.

[0064] The electricity price volatility correction factor is used to characterize the degree of electricity price volatility corresponding to the current trading session. In some embodiments, the electricity price volatility correction factor can be determined based on the electricity price sequence within the current trading session. The electricity price sequence within the current trading session includes multiple electricity price data points within the current trading session. By statistically analyzing the dispersion of each electricity price data point, the corresponding electricity price volatility correction factor can be determined.

[0065] Specifically, the electricity price volatility correction factor can be determined by the following formula (4): (4); in, This indicates the electricity price volatility correction factor for the current trading session. This represents the electricity price sequence within the current trading session; This represents the standard deviation of the electricity price series within the current trading session; This represents the average value of the electricity price series within the current trading period.

[0066] The standard deviation characterizes the dispersion of electricity price data relative to the average value within the current trading period, while the average value characterizes the average electricity price level within the current trading period. By determining the ratio between the standard deviation and the average value, the degree of electricity price volatility within the current trading period can be characterized, and the second basic electricity price threshold can be adjusted accordingly.

[0067] After determining the electricity price volatility correction factor, the adjustment amount of the second base electricity price threshold can be determined using this factor, so that the second electricity price threshold is different from the pre-set second base electricity price threshold and corresponds to the electricity price volatility situation corresponding to the current trading period.

[0068] Specifically, in some embodiments, the second electricity price threshold can be determined by the following formula (5): (5); in, This indicates the second electricity price threshold; This indicates the second basic electricity price threshold; This indicates the electricity price volatility correction factor for the current trading session. This represents the adjustment factor for the second base electricity price threshold.

[0069] Among them, the adjustment coefficient of the second basic electricity price threshold The adjustment range for adjusting the second base electricity price threshold is used. According to formula (5), the second base electricity price threshold, the electricity price volatility correction factor, and the second base electricity price threshold adjustment range coefficient can be used to jointly determine the second electricity price threshold, so that the electricity price volatility represented by the electricity price volatility correction factor can participate in the determination of the second electricity price threshold.

[0070] By using the above method, the electricity price fluctuation corresponding to the current trading period can be introduced to adjust the second basic electricity price threshold to obtain the second electricity price threshold. This allows the output of the photovoltaic inverter to be controlled based on the relationship between the real-time electricity price corresponding to the current trading period and the second electricity price threshold.

[0071] In some embodiments, a corresponding hysteresis bandwidth can be set for the first electricity price threshold and the second electricity price threshold based on the electricity price volatility correction factor corresponding to the current trading period. The hysteresis bandwidth is used to limit the switching of the judgment result caused by the real-time electricity price crossing the corresponding electricity price threshold when the real-time electricity price is near the first electricity price threshold or the second electricity price threshold, so as to avoid the judgment result switching frequently between adjacent electricity price intervals when the real-time electricity price fluctuates near the corresponding electricity price threshold.

[0072] Specifically, the hysteresis bandwidth can be determined based on the electricity price volatility correction factor corresponding to the current trading period and the corresponding electricity price threshold. The hysteresis bandwidth can be determined using the following formulas (6) and (7): (6); (7); in, This represents the hysteresis bandwidth corresponding to the first electricity price threshold. This represents the hysteresis bandwidth corresponding to the second electricity price threshold. This indicates the electricity price volatility correction factor for the current trading session. This indicates the first electricity price threshold. This indicates the second electricity price threshold.

[0073] After determining the hysteresis bandwidths corresponding to the first and second electricity price thresholds, the electricity price range within which the real-time electricity price falls can be determined by combining the hysteresis bandwidths. Specifically, for the corresponding electricity price threshold, the real-time electricity price... When the sum of the electricity price threshold and the corresponding hysteresis bandwidth is greater than or equal to the real-time electricity price threshold, the real-time electricity price is determined to switch to the price range above the threshold; in the real-time electricity price... When the difference between the electricity price threshold and the corresponding hysteresis bandwidth is less than the price threshold, the real-time electricity price is determined to switch to the price range below the price threshold.

[0074] Therefore, the real-time electricity price can be switched to the corresponding hysteresis judgment boundary before switching the price range. This reduces the frequent switching of the judgment result between adjacent price ranges when the real-time electricity price fluctuates near the first or second price threshold, thereby improving the stability of the subsequent photovoltaic inverter output control.

[0075] S203, when the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold, control the output power of the photovoltaic inverter to be less than or equal to the local load power.

[0076] When the real-time electricity price for the current trading period is lower than the first price threshold, it indicates that the current trading period is under low electricity price conditions. For example, the real-time electricity price could be a low positive or negative price. A low real-time electricity price usually indicates that the current electricity supply is relatively abundant or the electricity demand is relatively low. In this case, if the photovoltaic inverter still maintains a high output power, the portion of electricity exceeding the local load demand will still be output to the grid. Therefore, the output power of the photovoltaic inverter can be limited so that its output power is less than or equal to the local load power.

[0077] The local load power refers to the current power demand of the local load connected to the photovoltaic power generation system. When the output power of the photovoltaic inverter is less than or equal to the local load power, the electrical energy output by the photovoltaic inverter can be used entirely to meet the electricity demand of the local load, thereby avoiding the output of additional electrical energy to the grid due to the photovoltaic inverter's output power exceeding the local load power.

[0078] Therefore, when the real-time electricity price is low, the amount of electricity output from the photovoltaic inverter to the grid can be reduced, allowing the output power of the photovoltaic inverter to be dynamically adjusted according to the real-time electricity price.

[0079] S204, when the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition is determined as the target output power, and the photovoltaic inverter is controlled to output according to the target output power.

[0080] When the real-time electricity price for the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, it indicates that the current real-time electricity price is higher than the first electricity price threshold but has not yet reached the second electricity price threshold. Under this electricity price condition, the output power of the photovoltaic inverter can be determined by combining the local load's electricity demand and the power that the photovoltaic inverter can currently provide.

[0081] The maximum available power of a photovoltaic (PV) inverter under current operating conditions refers to the maximum output power that the PV inverter can achieve under the current operating conditions such as ambient temperature and irradiance. When the ambient temperature, irradiance, and other operating conditions change, the power that the PV strings connected to the PV inverter can provide will also change accordingly. Therefore, the maximum available power of the PV inverter can change with the current operating conditions.

[0082] To ensure that the output power of the photovoltaic inverter does not exceed either the local load power or the maximum available power that can actually be provided under the current operating conditions, the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating conditions can be determined as the target output power.

[0083] Specifically, the target output power can be determined by the following formula (8): (8); in, Indicates the target output power; Indicates local load power; This indicates the maximum available power of the photovoltaic inverter under the current operating conditions.

[0084] After determining the target output power, if the target output power is less than the maximum available power of the photovoltaic inverter under the current operating conditions, the operating voltage of the photovoltaic string connected to the photovoltaic inverter can be adjusted to make the photovoltaic string work at the operating point corresponding to the target output power, so that the output power of the photovoltaic inverter reaches the target output power.

[0085] In this embodiment of the application, controlling the photovoltaic inverter to output power according to the target output power includes: Based on the current ambient temperature and irradiance, the power-voltage characteristic curve of the photovoltaic string is corrected; based on the target output power, the target operating voltage corresponding to the target output power is determined on the corrected power-voltage characteristic curve; based on the target operating voltage, non-maximum power point tracking control is performed on the photovoltaic inverter to make the output power of the photovoltaic inverter reach the target output power.

[0086] Please refer to Figure 3 , Figure 3 This is a schematic diagram illustrating the operating point adjustment principle of the power-voltage characteristic curve of a photovoltaic string provided in an embodiment of this application.

[0087] like Figure 3 As shown, Figure 3 The diagram shows two power-voltage (PV) characteristic curves of a photovoltaic (PV) string under different operating conditions. The solid line represents the PV characteristic curve under standard test conditions, where the irradiance G is 1000 W / m² and the temperature T is 25°C. The dashed line represents the PV characteristic curve after correction based on the current ambient temperature and irradiance, where the irradiance G in the diagram is 800 W / m² and the temperature T is 35°C.

[0088] The maximum power point of the PV characteristic curve shown by the solid line is MPP1. The maximum power point voltage and maximum power corresponding to MPP1 are V and V, respectively. mpp1 and P max1 The maximum power point of the PV characteristic curve shown by the dashed line is MPP2. The maximum power point voltage and maximum power corresponding to MPP2 are V and V, respectively. mpp2 and P max2 .

[0089] Depend on Figure 3 It can be seen that after the operating conditions change, the PV characteristic curve corresponding to the photovoltaic string changes accordingly. max2 Less than P max1 And V mpp2 With V mpp1 They are different. Therefore, when determining the operating voltage of a photovoltaic string under its current operating conditions, the corrected PV characteristic curve can be used as the basis for determination.

[0090] Furthermore, at the target output power P target The maximum power P corresponding to the corrected PV characteristic curve is less than max2 In this case, the target output power P can be determined based on the specific circumstances. target On the corrected PV characteristic curve, determine the corresponding non-maximum power point (NMPPT) operating point, which corresponds to an operating voltage of V. op Thus, V opThe target operating voltage has been determined.

[0091] Determine the target operating voltage V op Then, the operating voltage of the photovoltaic string can be adjusted to move the operating point of the photovoltaic string on the corrected PV characteristic curve from MPP2 to the target operating voltage V. op The corresponding non-maximum power point operating point enables the photovoltaic string to achieve the target output power.

[0092] In some embodiments, proportional-integral (PI) control can be used to determine the control quantity based on the deviation between the target operating voltage and the current operating voltage of the photovoltaic string, and adjust the operating voltage of the photovoltaic string according to the control quantity so that the actual operating voltage of the photovoltaic string reaches the target operating voltage.

[0093] In the embodiments of this application, when the photovoltaic inverter is connected to multiple photovoltaic strings, the target output power can be allocated to each photovoltaic string, so that each photovoltaic string corresponds to a corresponding power allocation value. Based on the relationship between the available power of each photovoltaic string and the power allocation value, the output power of each photovoltaic string is controlled, so that the output power of each photovoltaic string is adapted to the power it can currently provide.

[0094] Specifically, when a photovoltaic inverter is connected to multiple photovoltaic strings, controlling the photovoltaic inverter to output power according to the target output power includes: The irradiance and temperature parameters of each photovoltaic string are obtained separately, and the available power of the corresponding photovoltaic string is determined based on the irradiance and temperature parameters of each photovoltaic string. When the available power of the photovoltaic string is greater than the corresponding power allocation value, the operating point voltage of the photovoltaic string is determined according to the power allocation value, and the operating voltage of the photovoltaic string is adjusted to the operating point voltage so that the output power of the photovoltaic string is reduced to the power allocation value. When the available power of the photovoltaic string is less than the corresponding power allocation value, the photovoltaic string is controlled to output according to the available power.

[0095] The available power of a photovoltaic (PV) string represents the power that the corresponding PV string can provide under the current irradiance and temperature conditions. Since the locations and illumination conditions of multiple PV strings may differ, the irradiance and temperature corresponding to different PV strings may also vary. Therefore, even if multiple PV strings are connected to the same PV inverter, the available power of each PV string under the current operating conditions may be different.

[0096] The power allocation value represents the output power of a specific photovoltaic (PV) string when multiple PV strings work together to achieve the target output power. By determining the corresponding power allocation value for each PV string, the target output power of the PV inverter can be distributed to each PV string, and control can be performed separately based on the current available power of each PV string.

[0097] Please refer to Figure 4 , Figure 4 This is a schematic diagram of power control for multiple photovoltaic strings provided in an embodiment of this application.

[0098] like Figure 4 As shown, the photovoltaic inverter is connected to multiple photovoltaic strings, with strings 1 to 4 as examples. The irradiance G of string 1 is 950 W / m², and the irradiance G of string 2 is 900 W / m². Strings 1 and 2 have relatively high usable power, and the aforementioned non-maximum power point tracking control (i.e., ...) can be used. Figure 4 The Non-MPPT derating method shown adjusts the operating voltage of the corresponding photovoltaic strings according to their respective power allocation values, so that they output according to their respective power allocation values. The irradiance G of string 3 is 400W / m², and the irradiance G of string 4 is 350W / m². The available power of strings 3 and 4 is relatively low, so they can output according to their respective available power (i.e., Figure 4 The MPPT shown is fully loaded.

[0099] Furthermore, Figure 4 The string-level decision unit is also illustrated. Based on the relationship between the available power of each photovoltaic string and its corresponding power allocation value, the string-level decision unit determines the output power of each photovoltaic string and coordinates the output power of each string. By independently judging the irradiance of each string and allocating the load reduction of each string, the total output power of multiple photovoltaic strings reaches the target output power P. target .

[0100] S205: When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, control the photovoltaic inverter to output the maximum available power corresponding to the current operating conditions.

[0101] When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, it indicates that the current real-time electricity price has reached the higher price level corresponding to the second electricity price threshold. At this time, there is no need to limit the output power of the photovoltaic inverter based on the local load power. Therefore, the photovoltaic inverter can be controlled to output the maximum available power corresponding to the current operating condition, so that the photovoltaic power that can be provided under the current operating condition can be fully output.

[0102] In some embodiments, the photovoltaic inverter can be subjected to maximum power point tracking control, so that the photovoltaic inverter outputs the maximum available power corresponding to the current operating conditions.

[0103] When a photovoltaic (PV) power generation system is connected to an energy storage device, the output power of the PV power generation system can be further increased by discharging through the energy storage device when the PV inverter outputs its maximum available power under the current operating conditions. To achieve this, a third base electricity price threshold can be preset, and adjusted according to the electricity price volatility correction factor corresponding to the current trading period to obtain the third electricity price threshold. The relationship between the real-time electricity price and the third electricity price threshold can then be used to determine whether the energy storage device should discharge.

[0104] Specifically, when the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, controlling the photovoltaic inverter to output the maximum available power corresponding to the current operating condition includes: When the real-time electricity price is greater than or equal to the second electricity price threshold and less than the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to stop charging and discharging; when the real-time electricity price is greater than or equal to the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to discharge at the maximum discharge power.

[0105] Specifically, when the real-time electricity price is greater than or equal to the second electricity price threshold but less than the third electricity price threshold, the real-time electricity price has not yet reached the level required for the energy storage device to participate in discharge. Therefore, while the photovoltaic inverter outputs the maximum available power corresponding to the current operating conditions, the energy storage device remains stopped charging and discharging. When the real-time electricity price is greater than or equal to the third electricity price threshold, it indicates that the real-time electricity price has reached the price level corresponding to the third electricity price threshold. At this time, based on the photovoltaic inverter outputting the maximum available power corresponding to the current operating conditions, the energy storage device can be controlled to discharge at its maximum discharge power to further improve the output power of the photovoltaic power generation system.

[0106] Therefore, the second and third electricity price thresholds can be used as the criteria for determining whether the photovoltaic inverter and energy storage device participate in power output. When the real-time electricity price reaches the second threshold, the photovoltaic inverter first outputs the maximum available power corresponding to the current operating conditions. When the real-time electricity price further reaches the third threshold, the energy storage device then participates in power output, thus allowing the output power of the photovoltaic power generation system to be further adjusted according to the electricity price range in which the real-time electricity price falls.

[0107] In some embodiments, the third electricity price threshold can be determined by the following formula (9): (9); in, Indicates the third electricity price threshold; This indicates the third basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the adjustment factor for the third base electricity price threshold.

[0108] The third basic electricity price threshold is used to provide the initial electricity price basis for the third electricity price threshold. According to formula (9), the third basic electricity price threshold can be adjusted by the electricity price volatility correction factor corresponding to the current trading period, so that the obtained third electricity price threshold is related to the electricity price volatility corresponding to the current trading period, and the third electricity price threshold is used as the judgment benchmark for the energy storage device to start discharging.

[0109] In summary, the dynamic control method for photovoltaic inverters provided in this application adjusts a first basic electricity price threshold based on the relationship between the used electricity and the total electricity quota within a preset statistical period, and adjusts a second basic electricity price threshold based on the electricity price volatility correction factor corresponding to the current trading period. This allows the first electricity price threshold to change with the usage of the electricity quota, and the second electricity price threshold to change with the electricity price fluctuations during the current trading period. Furthermore, based on the relationship between the real-time electricity price and the first and second electricity price thresholds, the output power of the photovoltaic inverter is limited in different electricity price ranges; the photovoltaic inverter is controlled to output at a target output power; or the photovoltaic inverter is controlled to output at the maximum available power corresponding to the current operating conditions. This allows the output power of the photovoltaic inverter to be adjusted in conjunction with the usage of the electricity quota, electricity price fluctuations, and the electricity price range in which the real-time electricity price is located. This avoids the difficulty in responding to price changes in a timely manner when using a fixed electricity price to determine boundaries or a fixed power limit, and improves the adaptability of the photovoltaic inverter's output power control to dynamically changing electricity prices.

[0110] This application also provides a dynamic control device for a photovoltaic inverter. Please refer to [link / reference]. Figure 5 , Figure 5 This is a structural diagram of the dynamic control device for a photovoltaic inverter provided in an embodiment of this application.

[0111] like Figure 5 As shown, the dynamic control device for this photovoltaic inverter includes: The first threshold adjustment module 501 is used to adjust the preset first basic electricity price threshold according to the relationship between the used electricity and the total electricity quota within a preset statistical period to obtain the first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold.

[0112] The second threshold adjustment module 502 is used to adjust the preset second basic electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold.

[0113] The first output control module 503 is used to control the output power of the photovoltaic inverter to be less than or equal to the local load power when the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold.

[0114] The second output control module 504 is used to determine the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition as the target output power when the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, and to control the photovoltaic inverter to output according to the target output power.

[0115] The third output control module 505 is used to control the photovoltaic inverter to output the maximum available power corresponding to the current operating condition when the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold.

[0116] In one exemplary embodiment of this application, adjusting a preset first base electricity price threshold based on the relationship between used electricity and total electricity quota within a preset statistical period to obtain a first electricity price threshold includes: The method involves determining the difference between the total electricity allowance and the used electricity; when the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the method decreases the first base electricity price threshold based on the difference between the ratio and the first proportional threshold to obtain the first electricity price threshold; when the ratio of the difference to the total electricity allowance is less than a second proportional threshold, the method increases the first base electricity price threshold based on the difference between the second proportional threshold and the ratio to obtain the first electricity price threshold; wherein the first proportional threshold is greater than the second proportional threshold.

[0117] In one exemplary embodiment of this application, when the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first electricity price threshold is determined by the following formula: ; When the ratio of the difference to the total electricity allowance is less than the second proportional threshold, the first electricity price threshold is determined by the following formula: ; in, This represents the first electricity price threshold; This represents the first basic electricity price threshold; This represents the second basic electricity price threshold; This represents the ratio of the difference to the total battery capacity. This represents the first proportional threshold; This represents the second proportional threshold; and These represent the first and second corrected gain coefficients, respectively. , .

[0118] In one exemplary embodiment of this application, adjusting the preset second base electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold includes: The second electricity price threshold is determined using the following formula: ; in, This represents the second electricity price threshold; This represents the second basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the second base electricity price threshold.

[0119] In one exemplary embodiment of this application, the photovoltaic power generation system in which the photovoltaic inverter is located includes an energy storage device, and the dynamic control device of the photovoltaic inverter is further used for: Based on the electricity price volatility correction factor corresponding to the current trading period, the preset third basic electricity price threshold is adjusted to obtain the third electricity price threshold; the third electricity price threshold is greater than the second electricity price threshold.

[0120] Based on this, when the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, controlling the photovoltaic inverter to output according to the maximum available power corresponding to the current operating condition includes: When the real-time electricity price is greater than or equal to the second electricity price threshold and less than the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to stop charging and discharging; when the real-time electricity price is greater than or equal to the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to discharge at the maximum discharge power.

[0121] In one exemplary embodiment of this application, the third electricity price threshold is determined by the following formula: ; in, This represents the third electricity price threshold; This represents the third basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the third basic electricity price threshold.

[0122] In one exemplary embodiment of this application, the photovoltaic inverter is connected to at least one photovoltaic string, and controlling the photovoltaic inverter to output power according to the target output power includes: Based on the current ambient temperature and irradiance, the power-voltage characteristic curve of the photovoltaic string is corrected; based on the target output power, a target operating voltage corresponding to the target output power is determined on the corrected power-voltage characteristic curve; based on the target operating voltage, non-maximum power point tracking control is performed on the photovoltaic inverter to make the output power of the photovoltaic inverter reach the target output power.

[0123] In one exemplary embodiment of this application, the photovoltaic inverter is connected to multiple photovoltaic strings, each of which has a corresponding power allocation value, wherein the sum of the power allocation values ​​corresponding to each photovoltaic string is equal to the target output power.

[0124] Controlling the photovoltaic inverter to output power according to the target output power includes: The irradiance and temperature parameters of each photovoltaic string are obtained respectively, and the available power of the corresponding photovoltaic string is determined according to the irradiance and temperature parameters of each photovoltaic string. When the available power of a photovoltaic string is greater than the corresponding power allocation value, the operating point voltage of the photovoltaic string is determined according to the power allocation value, and the operating voltage of the photovoltaic string is adjusted to the operating point voltage so that the output power of the photovoltaic string is reduced to the power allocation value. When the available power of a photovoltaic string is less than the corresponding power allocation value, the photovoltaic string is controlled to output according to the available power.

[0125] The specific details of each module of the dynamic control device of the aforementioned photovoltaic inverter have been described in detail in the corresponding dynamic control method of the photovoltaic inverter, so they will not be repeated here.

[0126] It should be noted that although several modules or units of the dynamic control device for photovoltaic inverters have been mentioned in the detailed description above, this division is not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0127] This application also provides an electronic device, please refer to... Figure 6 , Figure 6 This is a structural diagram of an electronic device provided in an embodiment of this application.

[0128] like Figure 6As shown, the electronic device 600 is presented in the form of a general-purpose computing device. The components of the electronic device 600 may include, but are not limited to: at least one processing unit 601, at least one storage unit 602, a bus 603 connecting different system components (including storage unit 602 and processing unit 601), and a display unit 604.

[0129] The storage unit stores program code that can be executed by the processing unit 601, causing the processing unit 601 to perform the steps described in the "Exemplary Methods" section of this specification according to various exemplary embodiments of this disclosure. For example, the processing unit 601 can perform actions such as... Figure 2 The steps are shown in the figure.

[0130] Storage unit 602 may include readable media in the form of volatile storage units, such as random access memory (RAM) 6021 and / or cache memory (Cache) 6022, and may further include read-only memory (ROM) 6023.

[0131] Storage unit 602 may also include a program / utility 6024 having a set (at least one) program module 6025, such program module 6025 including but not limited to: operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0132] Bus 603 can represent one or more of several types of bus structures, including a memory cell bus or memory cell controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of the various bus structures.

[0133] Electronic device 600 can also communicate with one or more external devices 607 (e.g., keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 600, and / or with any device that enables electronic device 600 to communicate with one or more other computing devices (e.g., router, modem, etc.). This communication can be performed via input / output (I / O) interface 605. Furthermore, electronic device 600 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 606. As shown, network adapter 606 communicates with other modules of electronic device 600 via bus 603. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 600, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0134] From the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, terminal device, or network device, etc.) to execute the methods according to the embodiments of this disclosure.

[0135] Other embodiments of this specification will readily occur to those skilled in the art upon consideration of the specification and practice of the invention claimed herein. This specification is intended to cover any variations, uses, or adaptations that follow the general principles of this specification and include common knowledge or customary techniques in the art not claimed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this specification are indicated by the following claims.

[0136] It should be understood that this specification is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this specification is limited only by the appended claims.

[0137] The above description is merely a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

Claims

1. A dynamic control method for a photovoltaic inverter, characterized in that, include: Based on the relationship between the used electricity and the total electricity quota within a preset statistical period, a preset first basic electricity price threshold is adjusted to obtain a first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold. Based on the electricity price volatility correction factor corresponding to the current trading period, the preset second basic electricity price threshold is adjusted to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold; When the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold, the output power of the photovoltaic inverter is controlled to be less than or equal to the local load power. When the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition is determined as the target output power, and the photovoltaic inverter is controlled to output according to the target output power; When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition.

2. The dynamic control method for a photovoltaic inverter according to claim 1, characterized in that, The step of adjusting the preset first basic electricity price threshold based on the relationship between the used electricity and the total electricity quota within a preset statistical period to obtain the first electricity price threshold includes: Determine the difference between the total available battery capacity and the amount of battery power already used; When the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first basic electricity price threshold is reduced based on the difference between the ratio and the first proportional threshold to obtain the first electricity price threshold. When the ratio of the difference to the total electricity allowance is less than the second proportional threshold, the first basic electricity price threshold is increased based on the difference between the second proportional threshold and the ratio to obtain the first electricity price threshold. Wherein, the first ratio threshold is greater than the second ratio threshold.

3. The dynamic control method for a photovoltaic inverter according to claim 2, characterized in that, When the ratio of the difference to the total electricity allowance is greater than or equal to a first proportional threshold, the first electricity price threshold is determined by the following formula: ； When the ratio of the difference to the total electricity allowance is less than the second proportional threshold, the first electricity price threshold is determined by the following formula: ； in, This represents the first electricity price threshold; This represents the first basic electricity price threshold; This represents the second basic electricity price threshold; This represents the ratio of the difference to the total battery capacity. This represents the first proportional threshold; This represents the second proportional threshold; and These represent the first and second corrected gain coefficients, respectively. , .

4. The dynamic control method for a photovoltaic inverter according to claim 1, characterized in that, The step of adjusting the preset second base electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold includes: The second electricity price threshold is determined using the following formula: ； in, This represents the second electricity price threshold; This represents the second basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the second base electricity price threshold.

5. The dynamic control method for a photovoltaic inverter according to claim 1, characterized in that, The photovoltaic power generation system in which the photovoltaic inverter is located includes an energy storage device, and the method further includes: Based on the electricity price volatility correction factor corresponding to the current trading period, the preset third basic electricity price threshold is adjusted to obtain the third electricity price threshold; the third electricity price threshold is greater than the second electricity price threshold. When the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold, controlling the photovoltaic inverter to output according to the maximum available power corresponding to the current operating condition includes: When the real-time electricity price is greater than or equal to the second electricity price threshold and less than the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to stop charging and discharging. When the real-time electricity price is greater than or equal to the third electricity price threshold, the photovoltaic inverter is controlled to output the maximum available power corresponding to the current operating condition, and the energy storage device is controlled to discharge at the maximum discharge power.

6. The dynamic control method for a photovoltaic inverter according to claim 5, characterized in that, The third electricity price threshold is determined by the following formula: ； in, This represents the third electricity price threshold; This represents the third basic electricity price threshold; This represents the electricity price volatility correction factor; This represents the correction factor for the third basic electricity price threshold.

7. The dynamic control method for a photovoltaic inverter according to claim 1, characterized in that, The photovoltaic inverter is connected to at least one photovoltaic string, and controlling the photovoltaic inverter to output power according to the target output power includes: The power-voltage characteristic curve of the photovoltaic string is corrected based on the current ambient temperature and irradiance. Based on the target output power, determine the target operating voltage corresponding to the target output power on the corrected power-voltage characteristic curve; Based on the target operating voltage, the photovoltaic inverter is subjected to non-maximum power point tracking control so that the output power of the photovoltaic inverter reaches the target output power.

8. The dynamic control method for a photovoltaic inverter according to claim 1, characterized in that, The photovoltaic inverter is connected to multiple photovoltaic strings, each of which has a corresponding power allocation value. The sum of the power allocation values ​​of each photovoltaic string is equal to the target output power. Controlling the photovoltaic inverter to output power according to the target output power includes: The irradiance and temperature parameters of each photovoltaic string are obtained respectively, and the available power of the corresponding photovoltaic string is determined based on the irradiance and temperature parameters of each photovoltaic string. When the available power of the photovoltaic string is greater than the corresponding power allocation value, the operating point voltage of the photovoltaic string is determined according to the power allocation value, and the operating voltage of the photovoltaic string is adjusted to the operating point voltage so that the output power of the photovoltaic string is reduced to the power allocation value. When the available power of the photovoltaic string is less than the corresponding power allocation value, the photovoltaic string is controlled to output according to the available power.

9. A dynamic control device for a photovoltaic inverter, characterized in that, include: The first threshold adjustment module is used to adjust the preset first basic electricity price threshold according to the relationship between the used electricity and the total electricity quota within the preset statistical period to obtain the first electricity price threshold; wherein, the smaller the ratio of the difference between the total electricity quota and the used electricity to the total electricity quota, the higher the first electricity price threshold. The second threshold adjustment module is used to adjust the preset second basic electricity price threshold according to the electricity price volatility correction factor corresponding to the current trading period to obtain the second electricity price threshold, wherein the second electricity price threshold is greater than the first electricity price threshold. The first output control module is used to control the output power of the photovoltaic inverter to be less than or equal to the local load power when the real-time electricity price corresponding to the current trading period is less than the first electricity price threshold. The second output control module is used to determine the minimum value between the local load power and the maximum available power of the photovoltaic inverter under the current operating condition as the target output power when the real-time electricity price corresponding to the current trading period is greater than or equal to the first electricity price threshold and less than the second electricity price threshold, and to control the photovoltaic inverter to output according to the target output power. The third output control module is used to control the photovoltaic inverter to output the maximum available power corresponding to the current operating condition when the real-time electricity price corresponding to the current trading period is greater than or equal to the second electricity price threshold.

10. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor, connected to the memory, is configured to implement the dynamic control method for a photovoltaic inverter as described in any one of claims 1 to 8 when executing the computer program.

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