A method, apparatus and equipment for grid-connected operation control of inverters in a photovoltaic power plant

Abstract

This invention provides a method, apparatus, and equipment for grid-connected operation control of inverters in a photovoltaic power plant. The method includes: acquiring basic operating data of a target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray; obtaining operating indicators based on the basic operating data; obtaining a subarray status label for each subarray based on the operating indicators; obtaining the scheduling priority and recommended adjustment direction for each subarray based on the subarray status label; acquiring grid scheduling targets and constraint parameters; obtaining the power allocation result for each subarray based on the grid scheduling targets and constraint parameters, the scheduling priority and recommended adjustment direction for each subarray, the basic operating data, and the operating indicators; and adjusting the power of the target inverters within each subarray based on the power allocation result for each subarray, and determining active power change slope limit parameters. This invention enables station-level power commands to be implemented in the active power output adjustment and slope limit execution of inverters under multiple constraint conditions.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a method, device and equipment for grid-connected operation control of inverters in photovoltaic power plants. Background Technology

[0002] High-proportion large-scale photovoltaic (PV) base grid-connected operation control technology, in ultra-large-scale PV base scenarios, typically involves multiple booster stations that integrate a large number of PV subarrays and string inverters. The receiving-end grid uses station-level active and reactive power commands to uniformly constrain the PV base's output. In engineering practice, the station control layer generally decomposes the station-level active power commands into subarray active power targets based on the installed capacity of each subarray or the current active power output ratio. Within each subarray, active power adjustments are then allocated according to the inverter's rated capacity or a simple equal distribution method. Simultaneously, existing reactive power and voltage control strategies are used to coordinate voltage and reactive power output adjustments at both the station and subarray levels. Operating units typically manage risks related to voltage exceeding limits, line overloads, and inverter protection actions by monitoring bus voltage, line current, inverter temperature, and alarm status, combined with protection settings and maintenance experience.

[0003] Existing technologies generally suffer from two main problems: First, station-level power allocation and inverter-level power adjustment rely heavily on internal and external monitoring data for hierarchical decision-making. Multi-dimensional state variables such as active power margin, voltage margin, line load margin, and inverter thermal margin lack unified indicators and a coordinated utilization mechanism, making it difficult to promptly identify local areas at voltage boundaries or under heavy line loads. Subarray sequencing and power allocation often depend primarily on single-scale metrics such as adjustable capacity, highlighting the significant conflict between local over-limit risks and global power command tracking. Second, the allocation of adjustment tasks at the inverter-level is weakly correlated with individual unit thermal history and derating behavior. Some inverters bear frequent and large-amplitude power adjustment tasks for extended periods, easily leading to increased temperature rise and protection operation frequency. Furthermore, parameters such as scheduling priorities, power adjustment boundaries, and power change slope limits rely heavily on initial experience settings, lacking a mechanism for systematic evaluation and adaptive optimization based on long-term operational performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method, device and equipment for grid-connected operation control of inverters in photovoltaic bases. Without configuring grid-type energy storage and without changing the physical structure of the existing boost station layer, sub-array layer and inverter single unit layer, the station-level power command can be smoothly decomposed and implemented to the active power output adjustment and slope limit execution of the inverter under multiple constraints.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A method for grid-connected operation control of inverters in a photovoltaic power plant includes: Acquire basic operational data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array; Based on the basic operating data, operating indicators characterizing the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray are obtained; Based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label. Obtain power grid dispatch objectives and constraint parameters; Based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, as well as the basic operating data and operating indicators, the power allocation results of each subarray within the target booster station are obtained. Based on the power allocation results of each subarray, the power of the target inverter in each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined.

[0006] Optionally, based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label, including: Determine the range of the active power margin, voltage margin, and line load margin indicators in the aforementioned operating indicators, respectively. Based on the aforementioned range, determine the active power margin range number, voltage margin range number, and line load margin range number. Based on the active power margin level number, voltage margin level number, and line load margin level number, the subarray status label of each subarray within the target substation is obtained. According to the preset mapping table, the subarray status labels are mapped to obtain the scheduling priority and recommended adjustment direction of each subarray.

[0007] Optionally, based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, and the basic operating data and operating indicators, the power allocation results of each subarray within the target booster station are obtained, including: Based on the power grid dispatching objectives and constraint parameters, as well as the basic operating data and operating indicators, the active power regulation demand of the target booster station is obtained. Based on the aforementioned basic operating data and operating indicators, the adjustable power range of each subarray within the target booster station is determined; Based on the adjustable power range of each subarray, and according to the scheduling priority and recommended adjustment direction of each subarray, the station-level active power regulation demand is allocated among multiple subarrays to obtain the power allocation result of each subarray within the target booster station.

[0008] Optionally, based on the aforementioned basic operating data and operating indicators, the adjustable power range of each subarray within the target booster station is determined, including: The initial adjustable power range of each subarray is determined based on the active power margin index in the aforementioned operating indicators; Based on the voltage margin index, the line load margin index, and the ramp rate constraint parameters in the pre-configured parameters, the preliminary adjustable power range is constrained to obtain the adjustable power range to be verified for each subarray. Obtain the transformer capacity constraints and transmission line capacity constraints of the target substation, summarize and verify the adjustable power range to be verified for each subarray, and obtain the adjustable power range of each subarray that meets the transformer capacity constraints and transmission line capacity constraints.

[0009] Optionally, based on the power allocation results of each subarray, the power of the target inverter within each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined, including: Based on the aforementioned basic operating data and operating indicators, determine the historical derating behavior indicators for each inverter within each subarray; Based on the aforementioned operating indicators and historical derating behavior indicators, a priority score value for each inverter is determined, and an adjustment priority sequence for all inverters within the subarray is determined based on the priority score value. Obtain the pre-configured parameters of the inverter, and determine the single-unit active power output adjustment boundary of each inverter based on the pre-configured parameters and operating indicators; Based on the adjustment priority sequence and the single-unit active power output adjustment boundary, the power allocation value of the subarray is allocated among multiple target inverters according to the adjustment priority sequence, so as to obtain the change in active power output of the target inverter. Obtain the convergence point voltage of the subarray and the local thermal state of the inverters within the subarray; Based on the collection point voltage and the inverter's thermal state, the current active power change slope limit parameter of the inverter is adjusted to obtain the adjusted active power change slope limit parameter of the target inverter.

[0010] Optionally, obtain the inverter's pre-configured parameters, and determine the single-unit active power output adjustment boundary for each inverter based on the pre-configured parameters and operating indicators, including: Based on the active power margin index in the aforementioned operating indicators, determine the initial adjustable active power range of the inverter; Based on the thermal margin index in the operating indicators, the ramp rate constraint parameter in the pre-configured parameters, and the station-level power change slope constraint parameter, the preliminary adjustable active power range is constrained to obtain the single-unit active power output adjustment boundary of the inverter; wherein, the ramp rate constraint parameter is determined according to the active power change slope limit parameter of the inverter.

[0011] Optionally, the grid-connected operation control method for photovoltaic power plant inverters also includes: Based on the adjusted inverter power and the adjusted current active power change slope limit parameter, obtain the current basic operating data and operating indicators; Based on the aforementioned basic operating data and operating indicators, determine the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, and power chattering evaluation quantity; Based on the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, power chattering evaluation quantity, and inverter protection operation frequency evaluation quantity, the preset mapping table, single-unit active power output adjustment boundary, and active power change slope limit parameters are adjusted. The present invention also provides a grid-connected operation control device for photovoltaic base inverters, comprising: The acquisition module is used to acquire basic operating data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array. The processing module is used to obtain operating indicators characterizing the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray, based on the basic operating data; obtain subarray status labels for each subarray within the target booster station based on the operating indicators, and obtain the scheduling priority and recommended adjustment direction for each subarray based on the subarray status labels; acquire grid scheduling targets and constraint parameters; obtain power allocation results for each subarray within the target booster station based on the grid scheduling targets and constraint parameters, the scheduling priority and recommended adjustment direction for each subarray, as well as the basic operating data and operating indicators; adjust the power of the target inverters within each subarray based on the power allocation results for each subarray, and determine the active power change slope limit parameters for the target inverters.

[0012] The present invention also provides a computing device, comprising: a processor and a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method described above.

[0013] The present invention also provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method described above.

[0014] The above-described solution of the present invention has at least the following beneficial effects: The above-described solution of the present invention acquires basic operating data of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray; based on the basic operating data, it obtains operating indicators characterizing the operating status of the target booster station, the multiple subarrays within the target booster station, and the multiple inverters within each subarray; based on the operating indicators, it obtains a subarray status label for each subarray within the target booster station, and obtains the scheduling priority and recommended adjustment direction for each subarray based on the subarray status label; it acquires grid scheduling targets and constraint parameters; based on the grid scheduling targets and constraint parameters, the scheduling priority and recommended adjustment direction for each subarray, and the basic operating data and operating indicators, it obtains the power allocation result for each subarray within the target booster station; based on the power allocation result for each subarray, it adjusts the power of the target inverter within each subarray and determines the active power change slope limit parameter for the target inverter. Without configuring grid-type energy storage or changing the physical structure of the existing booster station, subarray, and inverter unit layers, station-level power commands can be smoothly decomposed and implemented to the active power output adjustment and slope limit execution of the inverter under multiple constraints. Attached Figure Description

[0015] Figure 1 This is a flowchart of the photovoltaic base inverter grid-connected operation control method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the normalized operation index processing of the photovoltaic base inverter grid-connected operation control method according to an embodiment of the present invention. Figure 3 This is a flowchart of the three-layer collaborative power allocation of the photovoltaic base inverter grid-connected operation control method according to an embodiment of the present invention; Figure 4 This is a diagram of a three-layer collaborative power distribution unit for the grid-connected operation control method of photovoltaic base inverters according to an embodiment of the present invention; Figure 5 This is a structural diagram of the photovoltaic base inverter grid-connected operation control device according to an embodiment of the present invention. Detailed Implementation

[0016] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0017] like Figure 1 As shown, an embodiment of the present invention proposes a grid-connected operation control method for photovoltaic power plant inverters, comprising: Step 11: Obtain basic operating data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array; Here, in large-scale photovoltaic bases with a high proportion of new energy (such as the Shagohuang ultra-large-scale photovoltaic base), operational monitoring data are collected from the booster station layer, subarray layer and inverter single unit layer under a unified control cycle to construct the basic operation dataset X101.

[0018] At the substation level, the basic operating data includes the substation's total active power output, total reactive power output, 220kV bus voltage, 35kV bus voltage, and the active power and load factor of each outgoing line. At the subarray level, the basic operating data includes the collection point voltage, active power output, and reactive power output of the photovoltaic subarray. At the inverter unit level, the basic operating data includes the inverter's output voltage, output current, active power output, reactive power output, available active power, current harmonic index, casing or heat sink temperature, and alarm status.

[0019] Step 12: Based on the basic operating data, obtain operating indicators that characterize the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray; Here, as Figure 2 As shown, based on preset normalization rules and combined with configuration parameters such as rated active power output, voltage upper and lower limits, line allowable active power, and temperature upper limit, the basic operating data of each level obtained in step 11 are processed to calculate the corresponding normalized operating indicators. These operating indicators include active power margin, voltage margin, line load margin, and thermal margin. Corresponding active power margin, voltage margin, line load margin, and thermal margin indicators are generated for the target substation, multiple subarrays within the target substation, and multiple inverters within each subarray. These active power margin, voltage margin, line load margin, and thermal margin collectively serve as active power regulation indicators for the substation level, subarray level, and inverter unit level, forming a unified operating margin coordinate system. Under this unified operating margin coordinate system, the power regulation of individual inverter units and the power distribution of the subarray level are controlled.

[0020] Specifically, based on the available active power and current active power output in the basic operating data, and the rated active power output in the configuration parameters, the active power margin, representing the remaining adjustment space between the current output and the available output, is calculated. The active power margin is expressed as: ,in, For merit margin, Based on the data, the central inverter can utilize active power. Based on the current active power output of the corresponding level (boost station level, subarray level, or inverter unit level) in the basic running data, For the rated active power output in the configuration parameters, This is the denominator protection quantity, which is a preset non-zero positive number.

[0021] Based on the current bus voltage or subarray convergence point voltage from the basic operating data, and using the upper and lower allowable voltage limits in the configuration parameters as input, calculate the voltage margin, which represents the margin between the current voltage and the safe operating range. Specifically, first calculate the direction of voltage over-limit. ,in, For voltage over-limit direction, Based on the current bus voltage or subarray convergence point voltage in the dataset, For the voltage lower limit in the configuration parameters, This refers to the upper limit of voltage allowed in the configuration parameters. The direction of voltage exceeding the limit is determined using the formula... Calculate the voltage margin, where, For voltage margin, This is the denominator protection quantity, which is a preset non-zero positive number.

[0022] Based on the current active power of the line in the basic operating data and the allowable active power of the line in the configuration parameters, the line load margin, which characterizes the distance between the current load and the allowable load of the line, is calculated. Specifically, the line load margin is expressed as... ,in, For line load margin, The current active power of the outgoing lines in the base running dataset, For the line's allowed active power in the configuration parameters, This is the denominator protection quantity, which is a preset non-zero positive number.

[0023] Based on the inverter's key temperature measurement points in the basic operating data and the maximum allowable temperature in the configuration parameters, calculate the thermal margin characterizing the safe distance between the current temperature of the equipment and the maximum allowable temperature. Specifically, first calculate... ,in, For the maximum temperature of key temperature measurement points, The temperature of the key temperature measurement point of the first inverter, The temperature of the key temperature measurement point of the second inverter, The temperature of the critical temperature measurement point for the i-th inverter; based on the maximum value of the critical temperature measurement point temperature. calculate ,in, For heat margin, This indicates the upper limit of the allowable temperature in the configuration parameters. Indicates the reference temperature aperture, which is the preset temperature value. This represents the denominator protection quantity, which is a preset non-zero positive number.

[0024] The above denominator protection amount can be taken as an example. , , This is to avoid the normalization result diverging due to a denominator that is zero or too small, while ensuring that the quantity is sufficiently small relative to the rated value or allowable range width, so as not to change the margin ordering under normal operating conditions. A reference temperature can be taken as an example. The temperature is measured in °C, or the upper limit of the high quantile ambient temperature obtained from site statistics, with the unit being °C. This links the normalized benchmark of the thermal margin to the site's heat dissipation conditions, improving comparability between different seasons and different locations. The calculated active power margin, voltage margin, line load margin, and thermal margin are then associated with the corresponding step-up substation identifier, subarray identifier, inverter identifier, and time identifier, and written into the operation index set R101.

[0025] Step 13: Based on the operational indicators, obtain the subarray status label of each subarray within the target booster station, and obtain the scheduling priority and recommended adjustment direction of each subarray based on the subarray status label; Here, as Figure 3 As shown in step S102, based on the aforementioned operating indicators, the active power margin, voltage margin, and line load margin related to each photovoltaic subarray are discretized into multiple combinations to generate a subarray status label set R102 representing the current adjustable direction and safety space of the subarray. Furthermore, a mapping relationship is established between the subarray status labels and scheduling priorities and adjustment directions, forming a subarray scheduling priority set U102. This provides subarray status labels and subarray scheduling priorities for the subsequent three-layer coordinated power allocation and active power change slope constraint control chain, enabling station-level power allocation to consider voltage constraints, line constraints, and subarray output potential within a finite-dimensional state space. This differs from the conventional approach of sorting only by subarray adjustable capacity, and is more conducive to reducing constraint violations and improving subarray output utilization in high-proportion renewable energy transmission grids. Specifically, the subarray status label set R102 is used to centrally record the status label information of each photovoltaic subarray in the current control cycle, and the subarray scheduling priority set U102 is used to centrally record the scheduling priority level and recommended adjustment direction of each subarray in the current control cycle.

[0026] Step 14: Obtain the power grid dispatching objectives and constraint parameters; Here, the power grid dispatching target specifies the station-level active power output target and station-level reactive power output target for system regulation within the current control cycle. The constraint parameters include station-level power change slope constraint parameters. These station-level power change slope constraint parameters are used to limit the rate of change of the total active power output of the target booster station between adjacent control cycles, and at least include the control cycle duration. Upper limit of station-level power increase slope and the upper limit of the station-level power reduction slope Based on this, the allowable range of station-level active power variation for this control cycle is determined. ,in , , ,in, This indicates the total active power output at the station level during the current control cycle. This indicates the station-level active power execution target value for this control cycle. Indicates the duration of the control cycle, Indicates the maximum allowable rate of change in station-level power increase. Indicates the maximum allowable rate of change in power reduction at the station level; preferably, 1 minute can be taken. 5MW per minute is acceptable. A value of 5MW per minute can be adopted to avoid the station-level active power command changing too quickly in adjacent control cycles.

[0027] Step 15: Based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, as well as the basic operating data and operating indicators, obtain the power allocation results of each subarray within the target booster station; Here, as Figure 3 As shown in step S103, under the constraints of the station-level active power output target, station-level reactive power output target, and station-level power change slope constraint parameter given by the grid dispatch target and constraint parameters, based on the current total output within the station, and using the operation index set R101, the subarray status label set R102, and the subarray dispatch priority set U102 as inputs, the upper and lower boundaries of the adjustable active power for each photovoltaic subarray under the joint constraints of active power margin, voltage margin, and line load margin are calculated to obtain the adjustable power range of the subarray. Within this adjustable power range, the station-level active power increase or decrease is decomposed into the active power output adjustment of each subarray according to the dispatch priority using a step-by-step allocation algorithm, generating the station-level power allocation result set R103 for the target booster station. The station-level power allocation result set R103 records the active power output target value, active power output adjustment, and corresponding constraint utilization rate record for each photovoltaic subarray within the target booster station.

[0028] Step 16: Based on the power allocation results of each subarray, adjust the power of the target inverter in each subarray and determine the active power change slope limit parameter of the target inverter.

[0029] Here, as Figure 3As shown in step S104, based on the subarray active power output adjustment amount given in the station-level power allocation result set R103, and combined with the active power margin and thermal margin related to the inverter unit layer in the operation index set R101, the alarm status recorded in the basic operation dataset X101, and the historical derating behavior obtained from the historical records of the operation index set R101 and the basic operation dataset X101, the local regulation priority and unit active power output adjustment boundary are determined for the string inverters in each photovoltaic subarray. The subarray active power output adjustment amount is further subdivided into the target output change amount for each inverter, and the inverter power is adjusted according to the determined target output change amount. Furthermore, the corresponding unit active power change slope limit parameters are generated by combining the station-level power change slope constraint parameters, the subarray voltage state, and the local thermal state of each inverter.

[0030] The determined output change of the inverter and the slope limit parameter of the active power change of a single unit are written into the inverter power subdivision instruction and slope constraint set R104. The inverter power subdivision instruction and slope constraint set R104 records the identifier of the boost station, the identifier of the photovoltaic subarray, the inverter identifier, the current active power output, the target active power output, the change in active power output in the current control cycle, the adjustment boundary of the active power output of a single unit, and the slope limit parameter of the active power change of a single unit, and establishes a correlation with the time identifier.

[0031] The photovoltaic (PV) base inverter grid-connected operation control method of this embodiment is applicable to large-scale PV bases with a high proportion of new energy, including ultra-large-scale PV bases in desert areas. Without changing the existing hardware structure of the booster station, subarray, and inverter unit layers, and without configuring grid-type energy storage, it establishes a foundation of operational indicators that can simultaneously serve the booster station, subarray, and inverter unit layers. Furthermore, by combining simulation conditions and long-term operating data, it initializes and corrects decision parameters such as the mapping relationship between subarray status labels and scheduling priorities, and the power adjustment boundary of individual units. Based on this, it achieves smooth power command tracking and inverter load balancing that satisfy voltage and line constraints at the station, subarray, and inverter levels.

[0032] In an optional embodiment of the present invention, step 13, obtaining the subarray status label of each subarray within the target booster station based on the operational indicators, and obtaining the scheduling priority and recommended adjustment direction of each subarray based on the subarray status label, may include: Step 131: Determine the range of the active power margin, voltage margin, and line load margin indicators in the operation indicators respectively. Here, for each photovoltaic subarray, the current active power margin, voltage margin, and line load margin of that subarray are read from the operating index set R101. Based on the pre-configured normalization rules and threshold values, the active power margin, voltage margin, and line load margin are divided into corresponding threshold ranges.

[0033] Step 132: Determine the active power margin level number, voltage margin level number, and line load margin level number based on the level range. Here, based on the pre-configured normalization rules and gear thresholds, a number corresponding to the gear is generated for each margin indicator.

[0034] Step 133: Based on the active power margin level number, voltage margin level number, and line load margin level number, obtain the subarray status label of each subarray within the target booster station. Here, based on the combination of the three types of margin level numbers, a unique status label is assigned to each subarray, and the subarray identifier, subarray status label, and the three types of margin level numbers are written into the subarray status label set R102.

[0035] Step 134: Map the subarray status labels according to the preset mapping table to obtain the scheduling priority and recommended adjustment direction of each subarray.

[0036] Here, the mapping table specifies the mapping relationship between status labels and scheduling priorities and adjustment directions. The recommended adjustment directions include power increase adjustment direction, power decrease adjustment direction, and no change. According to the mapping table, the status labels in the subarray status label set R102 are mapped to scheduling priorities and recommended adjustment directions (by querying the scheduling priorities and recommended adjustment directions corresponding to the status labels in the mapping table). The mapping table is established based on simulation conditions and historical operating data, reflecting the impact of different status labels on voltage constraints, line constraints, and output tracking effects when performing power increase adjustment, power decrease adjustment, or no change. Based on this, an applicable priority level and recommended adjustment direction are configured for each status label. The mapping relationship can be pre-built during the offline analysis phase and updated online as needed using long-term operating data from the power grid. A finite mapping table between status labels and scheduling priorities and adjustment directions is maintained long-term using status labels as an index. Within a control cycle, the system looks up the priority level and recommended adjustment direction of the corresponding status label for each subarray, writes the subarray identifier, scheduling priority level, and recommended adjustment direction into the subarray scheduling priority set U102, and obtains the subarray scheduling priority record for the current control cycle.

[0037] Through the state label generation and scheduling priority mapping method in this embodiment, the multidimensional continuous margin can be compressed into a finite number of subarray state labels without changing the structure of the running margin index in the running index set R101. The scheduling priority and adjustment direction of each subarray are explicitly given in the subarray scheduling priority set U102, so that the subsequent station-level power allocation no longer directly deals with multidimensional continuous margin and complex constraints, but determines the scheduling object and adjustment direction on a finite state set by sorting and table lookup.

[0038] In an optional embodiment of the present invention, step 15, based on the power grid dispatching target and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, and the basic operating data and operating indicators, obtaining the power allocation result of each subarray within the target booster station may include: Step 151: Based on the power grid dispatching objectives and constraint parameters, as well as the basic operating data and operating indicators, obtain the station-level active power regulation demand of the target booster station; Here, based on the time identifier of the current control cycle, the system reads the current total active power output and total reactive power output within the station from the basic operation dataset X101. It also reads the station-level active power output target, station-level reactive power output target, and station-level power change slope constraint parameters for this control cycle from the power grid dispatch target and constraint parameter group. Furthermore, it obtains the allowable active power change range for this control cycle from the station-level power change slope constraint parameters. The system calculates the station-level active power increase or decrease based on the difference between the station-level active power output target and the current total active power output within the station. This increase or decrease is then limited to the allowable active power change range, resulting in the station-level active power regulation demand corrected by the slope constraint. The station-level reactive power output target is then used as the constraint input for subsequent reactive power and voltage control strategies.

[0039] Step 152: Based on the aforementioned basic operating data and operating indicators, determine the adjustable power range of each subarray within the target booster station; specifically, step 152 may include: Step 1521: Determine the initial adjustable power range for each subarray based on the active power margin index in the operational indicators. Here, the theoretical adjustable space of the subarray is calculated based on the active power margin; Step 1522: Based on the voltage margin index, the line load margin index, and the ramp rate constraint parameter in the pre-configured parameters, constrain the preliminary adjustable power range to obtain the adjustable power range to be verified for each subarray. Here, the adjustable space of subarrays under voltage margin constraints is narrowed, the adjustable space of each subarray on the transmission line with access load rate close to the upper limit is narrowed by line load margin constraints, and the maximum active power change in a single control cycle is limited by ramp rate constraints. After combining the above constraints, the upper and lower boundaries of active power adjustable range of each photovoltaic subarray are determined, forming the adjustable power range to be verified.

[0040] In an optional embodiment, a tiered contraction and interval truncation approach is adopted. Taking a subarray with an initial adjustable power range of 70MW to 130MW in the current control cycle and a current active power output of 100MW as an example, if the voltage margin is determined to be strained, the voltage contraction coefficient is taken from the voltage margin tiering mapping table. The upward adjustment space is truncated, so that the upper boundary of the adjustable active power is updated to... MW. If the line load margin is also determined to be strained, then the line contraction coefficient is taken from the line load margin classification mapping table. Based on the above, the upward adjustment space is further truncated, so that the upper boundary is updated to... The value is calculated in MW and rounded to 113MW with a preset precision. Then, based on the ramp rate constraint parameters, the maximum allowable active power change in a single control cycle is obtained. The adjustable power range of the subarray is obtained by limiting the upper boundary of active power adjustable power to 110MW and the lower boundary of active power adjustable power to 90MW. For subarrays with ample voltage or line load margins, the corresponding contraction steps are not executed; only the remaining constraints and interval truncation are retained.

[0041] Step 1523: Obtain the transformer capacity constraints and transmission line capacity constraints of the target substation, summarize and verify the adjustable power range to be verified for each subarray, and obtain the adjustable power range of each subarray that meets the transformer capacity constraints and transmission line capacity constraints.

[0042] Here, after obtaining the adjustable power range to be verified for each photovoltaic subarray, the adjustable power range to be verified for the subarray is summarized and verified according to the transmission line and step-up transformer based on the transformer capacity constraints and the transmission line capacity constraints. For situations that may cause the line load to exceed the allowable range or the transformer load to be close to the capacity limit for a long time, the corresponding adjustable power range is shrunk by lowering the upper boundary of the active power adjustable range of the relevant photovoltaic subarray. This ensures that the line load and transformer load are kept within the reserved safety margin range while meeting the station-level active power output target, thus obtaining the verified adjustable power range.

[0043] Step 153: Based on the adjustable power range of each subarray, and according to the scheduling priority and recommended adjustment direction of each subarray, the station-level active power regulation demand is allocated among multiple subarrays to obtain the power allocation result of each subarray within the target booster station.

[0044] Here, the station-level active power regulation demand, corrected by slope constraints, is used as the allocation target. The scheduling priority level and recommended adjustment direction recorded in the subarray scheduling priority set U102 are used as the sorting criteria to construct a candidate sequence of photovoltaic subarrays suitable for the current adjustment direction. For operating conditions requiring increased station-level active power output, the system prioritizes photovoltaic subarrays with a recommended adjustment direction of increasing power and a larger upper limit of adjustable active power to participate in regulation. For operating conditions requiring decreased station-level active power output, the system prioritizes photovoltaic subarrays with a recommended adjustment direction of decreasing power and a larger lower limit of adjustable active power to participate in regulation. The system traverses the candidate photovoltaic subarrays from high to low scheduling priority, gradually allocating active power output adjustment amounts without exceeding their respective adjustable power ranges. After each allocation, the system updates the unfulfilled station-level active power regulation demand until the station-level active power regulation demand is met or the adjustable power range of all photovoltaic subarrays is exhausted.

[0045] In this embodiment, for each photovoltaic subarray, the subarray identifier, current active power output, allocated active power output adjustment amount, and adjusted active power output target value are written into the station-level power allocation result set R103. Based on the operating indicators before and after allocation, the system calculates the subarray's utilization level of active power margin, voltage margin, and line load margin in the current control cycle, and writes the resulting constraint utilization rate record into R103. For photovoltaic subarrays not participating in this adjustment, the system records their active power output adjustment amount as zero, uses their current active power output as the active power output target value for this control cycle, and marks them as unchanged in the constraint utilization rate record. After completing the writing of R103, the system sends the station-level power allocation result set R103 to the subarray layer and inverter unit layer control links as the active power output target input for subsequent inverter unit power subdivision and slope constraint execution.

[0046] In this embodiment, within the same control cycle, the adjustable power range of each photovoltaic subarray is explicitly calculated using the active power margin, voltage margin, and line load margin in the operating index set R101. Then, combined with the discrete state sequence determined by the subarray status label set R102 and the subarray scheduling priority set U102, the station-level active power increase or decrease issued by the grid dispatch is gradually allocated. This differs from the conventional practice of allocating power solely based on installed capacity or a single margin ratio. This allows the station-level active power command tracking process to be carried out under the combined constraints of power change slope, transformer capacity, and transmission line capacity, reducing the risk of voltage exceeding limits and line overload. At the same time, it improves the output utilization of photovoltaic subarrays with sufficient active power margin and safe voltage and line load margins, and automatically reduces the weighting effect for photovoltaic subarrays with tight margins.

[0047] In an optional embodiment of the present invention, step 16, adjusting the power of the target inverter within each subarray based on the power allocation result of each subarray and determining the active power change slope limit parameter of the target inverter, may include: Step 161: Based on the basic operating data and operating indicators, determine the historical derating behavior indicators for each inverter in each subarray; Here, based on the time identifier of the current control cycle, the system reads the active power output adjustment and target value of each photovoltaic subarray from the station-level power allocation result set R103, and associates these data with the corresponding subarray identifier. Based on the subarray identifier, the system reads the pooling point voltage and active power output of the subarray in the current control cycle from the basic operation dataset X101, reads the active power margin, voltage margin, and thermal margin associated with each string inverter in the subarray from the operation index set R101, and reads the operation records associated with the alarm status of each inverter from the basic operation dataset X101. Within a preset statistical time window, based on the historical records of the operation index set R101 and the basic operation dataset X101 within that statistical time window, the system counts the number of derating operations, the duration of derating, and the number of times protection is triggered due to over-temperature or over-current for each inverter. The statistical results are recorded as the inverter's historical derating behavior index and associated with the corresponding inverter identifier.

[0048] Step 162: Determine the priority score value of each inverter based on the operating indicators and historical derating behavior indicators, and determine the adjustment priority sequence of all inverters within the subarray based on the priority score value; Here, for each photovoltaic subarray, the system first selects the set of inverters within that subarray that will participate in the current active power output adjustment. Inverters in a fault-outage state, a forced shutdown state, or a state where they are not allowed to participate in active power adjustment are marked as non-regulatory and not allocated any active power output change amount. For inverters in connected operation, the system generates a priority score value representing the local regulation priority by comprehensively considering their active power margin, thermal margin, alarm status, and historical derating behavior indicators. The priority score value increases with increasing active power margin, increasing thermal margin, and decreasing historical derating frequency, and decreases when there are multiple thermal protection actions or prolonged high-temperature alarm states. The system sorts the participating inverters according to their priority scores, obtaining a descending sequence of inverter regulation priorities within the subarray.

[0049] Preferably, the priority score can be generated by first obtaining a base score and then deducting a penalty score. The base score is determined by both active power margin and thermal margin. These two values ​​are converted to margin values ​​of 0 to 1 according to the normalization rule in step 12, and then weighted and averaged to obtain a score of 0 to 100. The weights can be pre-configured and are assumed to be the same by default. The penalty score is determined by alarm status and historical derating behavior. Alarm status can be calculated as follows: 0 points for no alarm, 10 points for a general alarm, and 30 points for a severe alarm. Historical derating behavior can be converted into deduction points based on the proportion of derating frequency and duration within a statistical time window, with additional deductions applied when thermal protection actions occur. The final priority score is the result of deducting the penalty score from the base score and is limited to the range of 0 to 100. The system sorts the priority scores from high to low to obtain an adjustment priority sequence. If the scores are the same, the inverter with higher thermal margin or less historical derating is selected first to maintain a stable ranking. For example, within the same subarray, inverter A has an active power margin of 0.8 and a thermal margin of 0.6, resulting in a base score of 70 points when weighted equally. Two derating events occur within the statistical window without alarms, deducting 10 points, resulting in a final score of 60 points. Inverter B has an active power margin of 0.6 and a thermal margin of 0.9, resulting in a base score of 75 points. While there are no derating events, a general alarm occurs, deducting 10 points, resulting in a final score of 65 points. Therefore, inverter B has a higher adjustment priority than inverter A in this control cycle.

[0050] Step 163: Obtain the pre-configured parameters of the inverter, and determine the single-unit active power output adjustment boundary of each inverter based on the pre-configured parameters and operating indicators; Specifically, step 163 may include: Step 1631: Determine the initial adjustable active power range of the inverter based on the active power margin index in the operating indicators. Here, the system limits its initial adjustable active power range to a range that does not exceed the available active power and is not lower than zero output, based on the inverter's active power margin. Step 1632: Based on the thermal margin index in the operating indicators, the ramp rate constraint parameter in the pre-configured parameters, and the station-level power change slope constraint parameter, constrain the preliminary adjustable active power range to obtain the single-unit active power output adjustment boundary of the inverter; wherein, the ramp rate constraint parameter is determined according to the active power change slope limit parameter of the inverter.

[0051] Here, based on the inverter's thermal margin, the initially adjustable active power range is narrowed under tight thermal margin conditions; based on the local ramp rate constraint parameter, the maximum output change within a single control cycle is limited to the local allowable ramp range; based on the station-level power change slope constraint parameter, the ramp space is allocated according to the capacity and priority scores of the inverters within the subarray, ensuring that the active power change rate of a single inverter does not exceed the upper limit of the local active power change slope derived from the station-level power change slope constraint parameter. After considering the above constraints, an upper boundary and a lower boundary of the allowable active power output change in the current control cycle are determined for each inverter, serving as the single-unit active power output adjustment boundary for that inverter.

[0052] Step 164: Based on the adjustment priority sequence and the single-unit active power output adjustment boundary, the power allocation value of the subarray is allocated among multiple target inverters according to the adjustment priority sequence to obtain the change in active power output of the target inverter. Here, after determining the allowable active power output adjustment boundaries for each inverter within the subarray, the system uses the active power output adjustment amount recorded in the station-level power allocation result set R103 as the target and performs a step-by-step subdivision allocation for each inverter within the subarray. For operating conditions requiring an increase in the active power output of the subarray, the system allocates the increase in active power output sequentially, starting with the inverter with the highest priority score, according to the inverter adjustment priority sequence. Each allocated increase in active power output does not exceed the upper boundary of the active power output change allowed in the current control cycle of that inverter. After each allocation, the system updates the active power output adjustment requirements of the subarray that have not yet been completed, until the active power output adjustment requirements of the subarray are met or the upper boundaries of the active power output change of all inverters participating in the adjustment within the subarray are exhausted. For operating conditions requiring a reduction in the active power output of a subarray, the system follows the inverter adjustment priority sequence, starting with inverters with higher priority scores and sufficient thermal margins, and sequentially assigning active power output reductions to them. Each allocated reduction does not exceed the lower boundary of the active power output change allowed in the current control cycle for that inverter. After each allocation, the system updates any remaining subarray active power output adjustment needs until the subarray's adjustment needs are met or the lower boundaries of the active power output changes for all participating inverters in the subarray are exhausted. Any remaining subarray active power output adjustment needs during the allocation process are recorded as incomplete adjustment needs, providing a basis for adjustments in subsequent control cycles or adjustments to higher-level control strategies.

[0053] Step 165: Obtain the convergence point voltage of the subarray and the local thermal state of the inverters within the subarray; Here, in order to suppress high-frequency jittering of inverter output power, the system adjusts the active power change slope limit parameters of each inverter according to the subarray convergence point voltage and the local thermal state of the inverter while performing active power output subdivision allocation.

[0054] Step 166: Based on the collection point voltage and the inverter's thermal state, adjust the current active power change slope limit parameter of the inverter to obtain the adjusted active power change slope limit parameter of the target inverter.

[0055] Here, when the subarray voltage is under pressure due to a tight voltage margin, while maintaining the overall active power regulation direction, the upper limit of the active power change slope limit for the inverters within the subarray is lowered. This makes the active power output adjustment process of the subarray smoother, thereby reducing the dynamic impact on the bus voltage. When the inverter's thermal state is close to the upper limit of the allowable temperature or when thermal protection derating is triggered multiple times within the most recent statistical time window, inverters with sufficient thermal margin are prioritized when allocating active power output adjustment. For inverters with tight thermal margins, a lower upper limit of the active power change slope limit and a smaller allowable output change range are set, allowing them to gradually fall back to a lower load level within the continuous control cycle, reducing the thermal stress caused by high-frequency, large-amplitude active power output changes.

[0056] In this embodiment, after determining the change in active power output and the single-unit active power change slope limit parameters for each inverter, the system writes the following fields into the inverter power subdivision instruction and slope constraint set R104: the identifier of the booster station to which the inverter belongs, the identifier of the photovoltaic subarray to which it belongs, the inverter identifier, the current active power output, the target active power output, the change in active power output within the current control cycle, and the corresponding single-unit active power change slope limit parameter. For inverters that do not participate in power regulation in this control cycle, the system records their active power output change as zero, uses the current active power output as the target active power output, and marks the single-unit active power change slope limit parameter in the inverter power subdivision instruction and slope constraint set R104 as the default value or unchanged. Based on the target active power output and active power change slope limit recorded in the inverter power subdivision instruction and slope constraint set R104, the control system generates a local power reference value and ramp constraint that conforms to the regulation target of this control cycle for each inverter, and sends the generated results to the inverter single-unit controller for execution. The ramp constraint generated based on the new active power change slope limit parameter will be used to determine the single-unit active power output adjustment boundary of the inverter in the next control cycle.

[0057] In this embodiment, without changing the structure of the operating margin index in the operating index set R101 and the data structure of the station-level power allocation result set R103, the active power output adjustment amount of the subarray layer is refined into the active power output change amount that can be executed at the inverter single-unit layer. At the same time, the active power change slope limit of each inverter is explicitly given in the inverter power subdivision instruction and slope constraint set R104. This is different from the conventional practice of simply amortizing the active power output adjustment amount among inverters according to the installed capacity or the current output ratio. This allows the inverter single-unit layer to comprehensively consider thermal margin, alarm status and historical derating behavior when tracking the station-level power allocation results. Through priority control and slope constraints, the high-frequency jitter and thermal stress accumulation risk of inverter output power are reduced, and execution records are provided by inverter for subsequent strategy threshold and parameter self-tuning based on operating performance.

[0058] In an optional embodiment of the present invention, the grid-connected operation control method for photovoltaic power plant inverters further includes: Step 171: Based on the adjusted inverter power and the adjusted current active power change slope limit parameter, obtain the current basic operating data and operating indicators; Here, the inverter power is adjusted based on the changes in active power output of each inverter and the limiting parameters of the slope of active power change for a single unit generated in the current control cycle. Newly generated basic operating data and operating indicators after inverter adjustment are also collected.

[0059] Step 172: Based on the basic operating data and operating indicators, determine the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, power chattering evaluation quantity, and inverter protection operation frequency evaluation quantity. Here, the statistical evaluation time window parameters are first configured to determine the time length and sliding step size for evaluating the operational effect. The statistical evaluation time window can be configured according to the number of control cycles, the length of natural time, or the typical working condition period.

[0060] Within each statistical evaluation time window, based on the active power output, reactive power output, voltage, and other operational monitoring quantities recorded in the basic operation dataset X101, and the subarray active power output target value recorded in the station-level power allocation result set R103, the difference between the station-level active power output target issued by the power grid dispatch and the actual total active power output within the station is statistically analyzed as the power command tracking deviation. The power tracking evaluation quantity is constructed by calculating the mean, absolute mean, and maximum value of the deviation.

[0061] Using the bus voltage and outgoing line load rate recorded in the basic operation dataset X101, and combined with the voltage margin and line load margin recorded in the operation index set R101, the number of bus voltage overruns, the duration of overruns, and the number of times the line load rate exceeds the allowable range within the statistical evaluation time window are statistically analyzed to construct voltage overrun evaluation quantities and line overload evaluation quantities.

[0062] Based on the inverter target active power output, current active power output, and active power output change recorded in the inverter power subdivision command and slope constraint set R104, the frequency and magnitude of power change of each inverter within the statistical evaluation time window are statistically analyzed. By calculating the number of times the output change magnitude exceeds the preset threshold per unit time or the number of times the active power output changes back and forth between adjacent control cycles, a power chattering evaluation quantity is constructed.

[0063] Based on the inverter alarm status and protection action records recorded in the basic operation dataset X101, the number of times and duration of inverter derating or shutdown caused by over-temperature protection, over-current protection or other protection actions are counted, and an inverter protection action frequency evaluation metric is constructed.

[0064] The above power tracking evaluation quantities, voltage over-limit evaluation quantities, line overload evaluation quantities, power chattering evaluation quantities, and inverter protection action frequency evaluation quantities are associated with the corresponding statistical evaluation time window identifiers and written as operation performance indicators into the operation performance evaluation and strategy correction record set R105.

[0065] Step 173: Adjust the preset mapping table, single-unit active power output adjustment boundary, and active power change slope limit parameters according to the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, power chattering evaluation quantity, and inverter protection operation frequency evaluation quantity. Here, within the statistical evaluation time window, based on the historical records of the subarray status label set R102 and the subarray scheduling priority set U102, and using the subarray status label as an index, the operational performance indicators in the operational performance evaluation and strategy correction record set R105 are statistically analyzed according to the subarray status label. For each subarray status label, the system counts the number of times power increase or decrease regulation is performed under that status label, the number of voltage over-limit related events, the number of line overload related events, and the corresponding power tracking evaluation quantity and power jitter evaluation quantity. It identifies high-risk status label combinations that are prone to voltage over-limit or line overload under the recommended regulation direction and current scheduling priority configuration, as well as status label combinations with large power jitter under the premise of meeting voltage and line constraints. The corresponding statistical results and risk mode markings are written into the operational performance evaluation and strategy correction record set R105.

[0066] For each subarray status label identified as having a high risk of exceeding limits, the mapping table in step 134 is adaptively corrected according to a preset safety priority correction rule. For subarray status labels that are repeatedly accompanied by voltage exceeding limits or line overload events during power increase regulation, the system lowers the scheduling priority level of the status label in the power increase regulation direction, or adjusts its recommended regulation direction from power increase to remaining unchanged or power decrease. For subarray status labels with persistently large power command tracking deviations under the premise of satisfying voltage and line constraints, the system appropriately increases the scheduling priority level of the subarray status label in the power increase regulation direction, provided that it does not exceed the preset single correction limit, so that subarrays with larger active power margins and good operating performance will have priority in undertaking output adjustment tasks in subsequent regulation. The update of the subarray status label mapping relationship is performed at the end of each statistical evaluation time window, and the scheduling priority configuration remains unchanged between adjacent statistical evaluation time windows to avoid frequent jumps in the scheduling strategy on the time axis.

[0067] Furthermore, based on the power jitter evaluation quantity and inverter protection action frequency evaluation quantity recorded in the inverter power subdivision command and slope constraint set R104 and the operation effect evaluation and strategy correction record set R105, adaptive corrections are made to the single-unit active power output adjustment boundary in step 163 and the single-unit active power change slope limit parameter in step 166. For the inverter set whose power jitter evaluation quantity continuously exceeds the preset threshold within multiple statistical evaluation time windows and no significant voltage over-limit or line overload events occur, under the premise of satisfying the station-level power change slope constraint parameter and inverter thermal margin constraint, the power change amplitude is reduced by tightening the single-unit active power output adjustment boundary of the corresponding inverter or lowering the upper limit of the single-unit active power change slope limit parameter, so as to reduce the power round-trip fluctuation within the subarray. For inverters that trigger over-temperature or over-current protection multiple times within the statistical evaluation time window, the available active power adjustment space in the power increase regulation direction is reduced, the amplitude and frequency of continuous power increase regulation are decreased, and the upper limit of the active power change slope limit is lowered. This allows the inverter to prioritize operation at a more conservative output level in subsequent control cycles, mitigating the accumulation of thermal stress. For operating conditions where the power command tracking deviation is consistently large without significant voltage overruns, line overloads, or inverter protection actions, the system can appropriately relax the single-unit active power output adjustment boundary and single-unit active power change slope limit parameters of some inverters, provided that safety constraints are met, to improve the overall power tracking capability.

[0068] After adaptively correcting the subarray status label mapping relationship, the single-unit active power output adjustment boundary, and the single-unit active power change slope limit parameters, the statistical results of the operation performance indicators, risk pattern identification results, corresponding scheduling priority adjustments, and single-unit constraint parameter corrections within each statistical evaluation time window are recorded in the operation performance evaluation and strategy correction record set R105. These records are then associated with the corrected subarray status label configuration and inverter parameter configuration. The operation performance evaluation and strategy correction record set R105 also records the scheduling priority configuration and single-unit constraint parameter configuration before and after correction, enabling parameter rollback or retuning when the correction effect does not meet expectations within multiple consecutive statistical evaluation time windows. When loading the preset mapping table in the next control cycle, the mapping table that has passed the strategy threshold and parameter self-tuning correction is used first to achieve closed-loop self-tuning between operation performance evaluation and power decision strategy.

[0069] The above embodiments of the present invention use the operation index set R101 as input, and construct a three-layer collaborative power allocation and active power change slope constraint control chain covering the boost station layer, subarray layer and inverter single unit layer through the subarray status label set R102, the subarray scheduling priority set U102, the station-level power allocation result set R103, and the inverter power subdivision instruction and slope constraint set R104. Based on the operation effect evaluation and strategy correction record set R105, the scheduling priority configuration and single unit constraint parameters are adaptively corrected on a statistical scale, so that the entire control strategy can be continuously adjusted according to the grid operation characteristics and equipment status changes under the condition of high proportion of new energy transmission in the ultra-large-scale photovoltaic base in the desert.

[0070] like Figure 4 As shown, the photovoltaic base inverter grid-connected operation control method of the present invention is executed through an operation data acquisition and operation index construction unit, a subarray status label generation and scheduling priority determination unit, a station-level multi-constraint power allocation unit, an inverter single-unit power subdivision and slope constraint execution unit, and a strategy threshold and parameter self-tuning unit. The operation data acquisition and operation index construction unit is used to collect operation monitoring quantities from the booster station layer, subarray layer and inverter single-unit layer under a unified control cycle to construct a basic operation dataset, and calculate a normalized operation margin index based on the basic operation dataset to generate an operation index set, so that the operation status of the booster station layer, subarray layer and inverter single-unit layer is characterized under a unified operation margin coordinate system.

[0071] The subarray status label generation and scheduling priority determination unit, the station-level multi-constraint power allocation unit, and the inverter single-unit power subdivision and slope constraint execution unit are used to construct a three-layer collaborative power allocation and active power change slope constraint control chain covering the booster station level, subarray level, and inverter single-unit level based on the operating index set. This chain determines the active power output adjustment amount for each subarray and the target active power output and active power change slope limits for each inverter level. Specifically, the subarray status label generation and scheduling priority determination unit generates a subarray status label set based on the operating index set and determines the mapping relationship between subarray status labels, scheduling priorities, and adjustment directions based on simulation conditions and historical operating data, forming a subarray scheduling priority set. The station-level multi-constraint power allocation unit calculates the station-level power allocation result set based on the subarray status label set, the subarray scheduling priority set, and the station-level active and reactive power targets, under the joint constraints of active power margin, voltage margin, and line load margin provided by the operating index set, and determines the active power output adjustment amount for each subarray. Based on the set of operating indicators and the set of station-level power allocation results, the inverter unit determines the active power output adjustment boundary and active power change slope limit for each inverter by combining the basic operating dataset during operation. It then generates the inverter power subdivision command and slope constraint set to drive the inverter to perform active power output adjustment.

[0072] The strategy threshold and parameter self-tuning unit statistically evaluates the operation effect of the photovoltaic power station and generates an operation effect evaluation and strategy correction record set. Based on this, the mapping relationship between subarray status labels, scheduling priorities and adjustment directions, as well as the adjustment boundary of single unit active power output and the limit of single unit active power change slope are adaptively corrected.

[0073] The above embodiments of the present invention map the operating states of the booster station layer, subarray layer, and inverter single-unit layer to the operating margin coordinate system based on a unified set of operating indicators. A collaborative power allocation and active power change slope constraint control chain covering the three-layer structure is constructed. Based on the operating effect evaluation and strategy correction record set, the subarray scheduling priority configuration and single-unit constraint parameters are self-tuned and updated. Thus, without increasing the grid-type energy storage configuration or changing the existing physical structure, smooth tracking of station-level power commands, effective maintenance of voltage and line safety margins, and long-term continuous optimization of the operating reliability of the inverter single-unit layer are achieved.

[0074] like Figure 5 As shown, an embodiment of the present invention also provides a photovoltaic base inverter grid-connected operation control device 50, comprising: The acquisition module 51 is used to acquire basic operating data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array. The processing module 52 is configured to: obtain operational indicators characterizing the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray, based on the basic operational data; obtain subarray status labels for each subarray within the target booster station based on the operational indicators, and obtain the scheduling priority and recommended adjustment direction for each subarray based on the subarray status labels; acquire grid scheduling targets and constraint parameters; obtain power allocation results for each subarray within the target booster station based on the grid scheduling targets and constraint parameters, the scheduling priority and recommended adjustment direction for each subarray, as well as the basic operational data and operational indicators; adjust the power of the target inverters within each subarray based on the power allocation results for each subarray, and determine the active power change slope limit parameters for the target inverters.

[0075] Optionally, based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label, including: Determine the range of the active power margin, voltage margin, and line load margin indicators in the aforementioned operating indicators, respectively. Based on the aforementioned range, determine the active power margin range number, voltage margin range number, and line load margin range number. Based on the active power margin level number, voltage margin level number, and line load margin level number, the subarray status label of each subarray within the target substation is obtained. According to the preset mapping table, the subarray status labels are mapped to obtain the scheduling priority and recommended adjustment direction of each subarray.

[0076] Optionally, based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, and the basic operating data and operating indicators, the power allocation results of each subarray within the target booster station are obtained, including: Based on the power grid dispatching objectives and constraint parameters, as well as the basic operating data and operating indicators, the active power regulation demand of the target booster station is obtained. Based on the aforementioned basic operating data and operating indicators, the adjustable power range of each subarray within the target booster station is determined; Based on the adjustable power range of each subarray, and according to the scheduling priority and recommended adjustment direction of each subarray, the station-level active power regulation demand is allocated among multiple subarrays to obtain the power allocation result of each subarray within the target booster station.

[0077] Optionally, based on the aforementioned basic operating data and operating indicators, the adjustable power range of each subarray within the target booster station is determined, including: The initial adjustable power range of each subarray is determined based on the active power margin index in the aforementioned operating indicators; Based on the voltage margin index, the line load margin index, and the ramp rate constraint parameters in the pre-configured parameters, the preliminary adjustable power range is constrained to obtain the adjustable power range to be verified for each subarray. Obtain the transformer capacity constraints and transmission line capacity constraints of the target substation, summarize and verify the adjustable power range to be verified for each subarray, and obtain the adjustable power range of each subarray that meets the transformer capacity constraints and transmission line capacity constraints.

[0078] Optionally, based on the power allocation results of each subarray, the power of the target inverter within each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined, including: Based on the aforementioned basic operating data and operating indicators, determine the historical derating behavior indicators for each inverter within each subarray; Based on the aforementioned operating indicators and historical derating behavior indicators, a priority score value for each inverter is determined, and an adjustment priority sequence for all inverters within the subarray is determined based on the priority score value. Obtain the pre-configured parameters of the inverter, and determine the single-unit active power output adjustment boundary of each inverter based on the pre-configured parameters and operating indicators; Based on the adjustment priority sequence and the single-unit active power output adjustment boundary, the power allocation value of the subarray is allocated among multiple target inverters according to the adjustment priority sequence, so as to obtain the change in active power output of the target inverter. Obtain the convergence point voltage of the subarray and the local thermal state of the inverters within the subarray; Based on the collection point voltage and the inverter's thermal state, the current active power change slope limit parameter of the inverter is adjusted to obtain the adjusted active power change slope limit parameter of the target inverter.

[0079] Optionally, obtain the inverter's pre-configured parameters, and determine the single-unit active power output adjustment boundary for each inverter based on the pre-configured parameters and operating indicators, including: Based on the active power margin index in the aforementioned operating indicators, determine the initial adjustable active power range of the inverter; Based on the thermal margin index in the operating indicators, the ramp rate constraint parameter in the pre-configured parameters, and the station-level power change slope constraint parameter, the preliminary adjustable active power range is constrained to obtain the single-unit active power output adjustment boundary of the inverter; wherein, the ramp rate constraint parameter is determined according to the active power change slope limit parameter of the inverter.

[0080] Optionally, the processing module 52 can also be used for: Based on the adjusted inverter power and the adjusted current active power change slope limit parameter, obtain the current basic operating data and operating indicators; Based on the aforementioned basic operating data and operating indicators, determine the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, and power chattering evaluation quantity; Based on the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, power chattering evaluation quantity, and inverter protection operation frequency evaluation quantity, the preset mapping table, single-unit active power output adjustment boundary, and active power change slope limit parameters are adjusted.

[0081] It should be noted that this device is the same as the method described above. All implementations in the above method embodiments are applicable to the embodiments of this device and can achieve the same technical effect.

[0082] Embodiments of the present invention also provide a computing device, including: a processor and a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method as described above. All implementations in the above method embodiments are applicable to this embodiment and can achieve the same technical effects.

[0083] Embodiments of the present invention also provide a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method as described above. All implementations in the above method embodiments are applicable to this embodiment and can achieve the same technical effects.

[0084] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0085] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0086] In the embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0087] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0088] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0089] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

[0090] Furthermore, it should be noted that in the apparatus and method of the present invention, it is obvious that the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalent solutions of the present invention. Moreover, the steps performing the above series of processes can naturally be executed in the order described, but are not necessarily required to be executed in chronological order; some steps can be executed in parallel or independently of each other. Those skilled in the art will understand that all or any step or component of the method and apparatus of the present invention can be implemented in any computing device (including processors, storage media, etc.) or network of computing devices, in hardware, firmware, software, or a combination thereof. This is something that those skilled in the art can achieve using their basic programming skills after reading the description of the present invention.

[0091] Therefore, the object of the present invention can also be achieved by running a program or a set of programs on any computing device. The computing device can be a known general-purpose device. Therefore, the object of the present invention can also be achieved simply by providing a program product containing program code implementing the method or apparatus. That is, such a program product also constitutes the present invention, and the storage medium storing such a program product also constitutes the present invention. Obviously, the storage medium can be any known storage medium or any storage medium developed in the future. It should also be noted that in the apparatus and method of the present invention, it is obvious that the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalent to the present invention. Furthermore, the steps performing the above series of processes can naturally be performed in the order described, but are not necessarily required to be performed in chronological order. Some steps can be performed in parallel or independently of each other.

[0092] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for grid-connected operation control of a photovoltaic power plant inverter, characterized in that, include: Acquire basic operational data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array; Based on the basic operating data, operating indicators characterizing the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray are obtained; Based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label. Obtain power grid dispatch objectives and constraint parameters; Based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, as well as the basic operating data and operating indicators, the power allocation results of each subarray within the target booster station are obtained. Based on the power allocation results of each subarray, the power of the target inverter in each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined. Specifically, based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label, including: Determine the range of the active power margin, voltage margin, and line load margin indicators in the aforementioned operating indicators, respectively. Based on the aforementioned range, determine the active power margin range number, voltage margin range number, and line load margin range number. Based on the active power margin level number, voltage margin level number, and line load margin level number, the subarray status label of each subarray within the target substation is obtained. According to the preset mapping table, the subarray status labels are mapped to obtain the scheduling priority and recommended adjustment direction of each subarray; Specifically, based on the power allocation results of each subarray, the power of the target inverter within each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined, including: Based on the aforementioned basic operating data and operating indicators, determine the historical derating behavior indicators for each inverter within each subarray; Based on the aforementioned operating indicators and historical derating behavior indicators, a priority score value for each inverter is determined, and an adjustment priority sequence for all inverters within the subarray is determined based on the priority score value. Obtain the pre-configured parameters of the inverter, and determine the single-unit active power output adjustment boundary of each inverter based on the pre-configured parameters and operating indicators; Based on the adjustment priority sequence and the single-unit active power output adjustment boundary, the power allocation value of the subarray is allocated among multiple target inverters according to the adjustment priority sequence, so as to obtain the change in active power output of the target inverter. Obtain the convergence point voltage of the subarray and the local thermal state of the inverters within the subarray; Based on the collection point voltage and the inverter's thermal state, the current active power change slope limit parameter of the inverter is adjusted to obtain the adjusted active power change slope limit parameter of the target inverter.

2. The photovoltaic base inverter grid-connected operation control method according to claim 1, characterized in that, Based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, and the basic operating data and operating indicators, the power allocation results for each subarray within the target booster station are obtained, including: Based on the power grid dispatching objectives and constraint parameters, as well as the basic operating data and operating indicators, the active power regulation demand of the target booster station is obtained. Based on the aforementioned basic operating data and operating indicators, the adjustable power range of each subarray within the target booster station is determined; Based on the adjustable power range of each subarray, and according to the scheduling priority and recommended adjustment direction of each subarray, the station-level active power regulation demand is allocated among multiple subarrays to obtain the power allocation result of each subarray within the target booster station.

3. The photovoltaic base inverter grid-connected operation control method according to claim 2, characterized in that, Based on the aforementioned basic operational data and operational indicators, the adjustable power range of each subarray within the target booster station is determined, including: The initial adjustable power range of each subarray is determined based on the active power margin index in the aforementioned operating indicators; Based on the voltage margin index, the line load margin index, and the ramp rate constraint parameters in the pre-configured parameters, the preliminary adjustable power range is constrained to obtain the adjustable power range to be verified for each subarray. Obtain the transformer capacity constraints and transmission line capacity constraints of the target substation, summarize and verify the adjustable power range to be verified for each subarray, and obtain the adjustable power range of each subarray that meets the transformer capacity constraints and transmission line capacity constraints.

4. The photovoltaic base inverter grid-connected operation control method according to claim 1, characterized in that, Obtain the pre-configured parameters of the inverters, and determine the single-unit active power output adjustment boundary for each inverter based on the pre-configured parameters and operating indicators, including: Based on the active power margin index in the aforementioned operating indicators, determine the initial adjustable active power range of the inverter; Based on the thermal margin index in the operating indicators, the ramp rate constraint parameter in the pre-configured parameters, and the station-level power change slope constraint parameter, the preliminary adjustable active power range is constrained to obtain the single-unit active power output adjustment boundary of the inverter; wherein, the ramp rate constraint parameter is determined according to the active power change slope limit parameter of the inverter.

5. The photovoltaic base inverter grid-connected operation control method according to claim 1, characterized in that, Also includes: Based on the adjusted inverter power and the adjusted current active power change slope limit parameter, obtain the current basic operating data and operating indicators; Based on the aforementioned basic operating data and operating indicators, determine the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, and power chattering evaluation quantity; Based on the power tracking evaluation quantity, voltage over-limit evaluation quantity, line overload evaluation quantity, power chattering evaluation quantity, and inverter protection operation frequency evaluation quantity, the preset mapping table, single-unit active power output adjustment boundary, and active power change slope limit parameters are adjusted.

6. A grid-connected operation control device for a photovoltaic power plant inverter, characterized in that, include: The acquisition module is used to acquire basic operating data of the target booster station, multiple sub-arrays within the target booster station, and multiple inverters within each sub-array. The processing module is used to obtain operating indicators that characterize the operating status of the target booster station, multiple subarrays within the target booster station, and multiple inverters within each subarray, based on the basic operating data. Based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label; the power grid scheduling target and constraint parameters are obtained. Based on the power grid dispatching objectives and constraint parameters, the dispatching priority and recommended adjustment direction of each subarray, as well as the basic operating data and operating indicators, the power allocation results of each subarray within the target booster station are obtained. Based on the power allocation results of each subarray, the power of the target inverter in each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined. Specifically, based on the operational indicators, the subarray status label of each subarray within the target booster station is obtained, and the scheduling priority and recommended adjustment direction of each subarray are obtained based on the subarray status label, including: Determine the range of the active power margin, voltage margin, and line load margin indicators in the aforementioned operating indicators, respectively. Based on the aforementioned range, determine the active power margin range number, voltage margin range number, and line load margin range number. Based on the active power margin level number, voltage margin level number, and line load margin level number, the subarray status label of each subarray within the target substation is obtained. According to the preset mapping table, the subarray status labels are mapped to obtain the scheduling priority and recommended adjustment direction of each subarray; Specifically, based on the power allocation results of each subarray, the power of the target inverter within each subarray is adjusted, and the active power change slope limit parameter of the target inverter is determined, including: Based on the aforementioned basic operating data and operating indicators, determine the historical derating behavior indicators for each inverter within each subarray; Based on the aforementioned operating indicators and historical derating behavior indicators, a priority score value for each inverter is determined, and an adjustment priority sequence for all inverters within the subarray is determined based on the priority score value. Obtain the pre-configured parameters of the inverter, and determine the single-unit active power output adjustment boundary of each inverter based on the pre-configured parameters and operating indicators; Based on the adjustment priority sequence and the single-unit active power output adjustment boundary, the power allocation value of the subarray is allocated among multiple target inverters according to the adjustment priority sequence, so as to obtain the change in active power output of the target inverter. Obtain the convergence point voltage of the subarray and the local thermal state of the inverters within the subarray; Based on the collection point voltage and the inverter's thermal state, the current active power change slope limit parameter of the inverter is adjusted to obtain the adjusted active power change slope limit parameter of the target inverter.

7. A computing device, characterized in that, include: A processor, a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, A storage instruction that, when executed on a computer, causes the computer to perform the method as described in any one of claims 1 to 5.

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