A photovoltaic power generation management and control system

Abstract

This invention relates to the field of photovoltaic power generation management system technology, specifically a photovoltaic power generation management, control and regulation system. By integrating AGC active power dynamic allocation, AVC reactive power collaborative compensation, virtual inertia frequency response and reverse power fast protection technology, it achieves multi-objective collaborative optimization. The system adopts a priority control strategy, a hybrid reactive power allocation algorithm and a multi-level interlocking protection mechanism, which significantly improves grid stability and regulation accuracy, and meets the grid connection requirements of large-scale photovoltaic power plants.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic management system technology, and more specifically, to a photovoltaic power generation management, control and regulation system. Background Technology

[0002] With the rapid development of photovoltaic power generation technology, grid-connected operation of large-scale photovoltaic power plants has become the mainstream trend. However, existing photovoltaic management systems still have significant technical defects in power control, grid stability, and equipment protection. Traditional inverters usually adopt a single control mode (only supporting active power regulation or reactive power compensation), which cannot achieve dynamic coordination between automatic generation control (AGC) and automatic voltage control (AVC). The separation of reactive and active power control leads to insufficient grid stability. At the same time, there is also insufficient dynamic adjustment capability, making it difficult to cope with complex operating conditions. Existing technologies have not solved the problems of multi-device collaborative allocation, dynamic inertia adjustment, and reverse power prediction, resulting in insufficient grid-connected stability of large-scale photovoltaic power plants. For example, the edge computing wind-solar-storage AGC / AVC coordinated control system and method based on edge computing, patent publication number CN112421695B, discloses a control management system with the above problems.

[0003] Therefore, to address the above problems, a photovoltaic power generation management and control system is proposed, which features AGC active power dynamic allocation, AVC reactive power collaborative compensation, virtual inertia frequency response, and reverse power fast protection technology, in order to achieve better management and control of the photovoltaic power generation system. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a photovoltaic power generation management and control system to solve the problems existing in the background technology.

[0005] The above-mentioned technical objective of this invention is achieved through the following technical solution: a photovoltaic power generation management and control system, comprising a data acquisition module installed at the grid-connected node of the photovoltaic power generation system for collecting and transmitting various operational data of the grid-connected node in real time; a system scheduling module that, based on the photovoltaic grid-connected power adjustment issued by the power grid dispatching station and the data transmitted by the data acquisition module, determines whether regulation is required, and then issues active power scheduling instructions and / or reactive power scheduling instructions for the photovoltaic power generation system based on the regulation conditions; an AGC active power regulation module that, based on the active power scheduling instructions, dynamically adjusts the active power output of the inverter through a priority allocation strategy, thereby regulating the grid-connected power of the photovoltaic grid-connected node; an AVC reactive power regulation module that, based on the reactive power scheduling instructions, coordinates the reactive power output of the reactive power compensation device and the inverter, thereby regulating the grid-connected voltage of the photovoltaic power generation system's grid-connected node; and a dynamic response module that monitors the frequency fluctuations of the photovoltaic power grid and generates dynamic regulation instructions using virtual synchronous machine control and fuzzy PID regulation.

[0006] Optionally, the AGC active power regulation module includes: a first instruction receiving unit, used to receive active power scheduling instructions issued by the system scheduling module, and then parse out the total active power target value; a first scheduling calculation unit, used to receive data transmitted by the data acquisition module and data transmitted by the first instruction receiving unit to calculate the regulation target correction value; a first strategy allocation unit, used to generate and transmit power increase regulation strategy instructions or power decrease regulation strategy instructions according to the calculation results of the first scheduling calculation unit; and a first instruction issuing unit, used to issue the regulation instructions generated by the first strategy allocation unit to the inverters of the grid-connected nodes of the photovoltaic power generation system in batches, and monitor the regulation results. If the target value is not reached, a fine-tuning mechanism is triggered.

[0007] Optionally, the AVC reactive power regulation module includes: a second instruction receiving unit, used to receive reactive power scheduling instructions issued by the system scheduling module, and then parse out the voltage target value or reactive power target value; a second scheduling calculation unit, used to receive data transmitted by the data acquisition module and data transmitted by the second instruction receiving unit to generate reactive power regulation strategy instructions; and a second instruction issuing unit, used to issue the reactive power regulation strategy instructions generated by the second scheduling calculation unit to the equipment of the grid-connected node of the photovoltaic power generation system in steps.

[0008] Optionally, the dynamic response module includes: a virtual synchronous machine control unit, which simulates the inertial response characteristics of a synchronous generator based on the data collected by the data acquisition module, thereby stabilizing the photovoltaic power grid frequency; a fuzzy PID power smoothing control unit, which suppresses power step changes caused by sudden changes in illumination, thereby stabilizing the photovoltaic power grid power; and a multi-objective coordination logic unit, which coordinates the outputs of the virtual synchronous machine and the fuzzy PID, and issues the dynamic adjustment command after coordination to avoid control conflicts.

[0009] Optionally, it also includes: an anti-reverse current module for predicting the reverse power trend of the photovoltaic power grid and executing multi-level interlocking protection actions; the anti-reverse current module includes: a reverse power calculation unit, which calculates the real-time reverse power value and the reverse power value in the future time period based on the data transmitted by the data acquisition module, thereby obtaining the real-time reverse power value and the reverse power prediction value, and compares them with the corresponding reverse power threshold to generate a first-level protection command or a second-level protection command for transmission; a multi-level interlocking protection execution unit, which can be used to adjust the inverter output power to 90% of the load demand when the first-level protection command is received, thereby achieving rapid adjustment protection; or it can be used to disconnect the grid-connected contactor and start the energy storage charging or unloading device when the second-level protection command is received, thereby achieving the protection effect; an alarm and feedback unit, which pushes alarm information to the monitoring interface in real time, synchronously generates an event log, and records the triggering event, protection level and equipment status.

[0010] Optionally, the specific execution steps of the AGC active power regulation module are as follows:

[0011] Step A: The first instruction receiving unit receives the active power scheduling instruction issued by the system scheduling module, and then parses out the total active power target value P in the active power scheduling instruction. target And simultaneously check whether it is within the adjustable range of the photovoltaic power grid;

[0012] Step B: Based on the total active power target value, perform target value correction, and then use the corrected control target value, denoted as P, for control. ntarget =P target +∑P inow -P now , where ∑P inow It represents the sum of the real-time power of all inverters participating in the regulation, and n represents the number of grid-connected nodes of the photovoltaic power generation system participating in the regulation;

[0013] Step C, Step C, the first strategy allocation unit is based on the power difference, represented as P AGC =P ntarget -P now When P AGC When P > 0, a power increase adjustment strategy instruction is generated; when P AGC If <0, generate a power reduction adjustment strategy instruction;

[0014] Step D: The first instruction issuing unit divides the received power increase or power decrease adjustment strategy instructions into steps and issues them in batches to the inverters of each grid-connected node of the photovoltaic power generation system. When it is a power increase adjustment strategy instruction, it is allocated from high to low priority according to the inverters of the grid-connected node of the photovoltaic power generation system, as shown in step D. When the power reduction regulation strategy command is issued, it is allocated according to the priority status of the inverters at the grid-connected nodes of the photovoltaic power generation system from low to high, as represented as:

[0015] Step E: The first instruction issuing unit synchronously monitors the control results. If the target value is not reached, a fine-tuning mechanism is triggered, indicating that... Where K adjust It is represented as the control coefficient.

[0016] Optionally, the specific execution steps of the AVC reactive power regulation module are as follows:

[0017] Step A: The second instruction receiving unit receives the reactive power scheduling instruction issued by the system scheduling module, and then parses out the reactive power target value Q in the reactive power scheduling instruction. target and voltage target value U target ;

[0018] Step B: The second scheduling calculation unit receives the real-time voltage value U of each photovoltaic power generation system's grid-connected node collected by the data acquisition module. mea reactive power Q mea SVC / SVG equipment operating status and inverter no-function capacity Q at grid connection point gimax ;

[0019] Step C: The second scheduling calculation unit calculates the reactive power regulation strategy instructions, wherein the reactive power regulation strategy instructions include a first reactive power regulation instruction, a second reactive power regulation instruction, and a third reactive power regulation instruction; when Q target ≤λQ svg In this case, it means that only the SVC / SVG device is responsible, only the output target voltage of the SVC / SVG device is adjusted, the first reactive power regulation command is generated and transmitted; when λQ svg target ≤λQ svg +∑Q gimax In this case, the reactive power difference of the inverter is preferentially allocated, denoted as ΔQ. g =Q target -λQ svg The remaining reactive power difference is compensated by the SVC / SVG device, generating a second reactive power adjustment command and transmitting it; when Q target Q svg +∑Q gimax In this case, it means that the reactive power output value of the inverter is adjusted to Q. gimax The voltage value of SVC / SVG equipment is according to U target Adjustment is performed, at which point the adjustment limit has been triggered, generating a third reactive power adjustment command and an over-limit alarm warning, which are transmitted synchronously; where λ represents the weighting coefficient.

[0020] Step D: The second instruction issuing unit receives the first reactive power adjustment instruction, the second reactive power adjustment instruction, or the third reactive power adjustment instruction, and issues the corresponding adjustment instruction to the corresponding equipment according to the step size to complete the reactive power adjustment.

[0021] Optionally, the step size controlled in the AGC module means limiting the adjustment range of active power, denoted as ΔP. step =η·P rated Where η represents the step size ratio, P rated This is expressed as the rated active power of the inverter at the corresponding photovoltaic power generation grid connection point.

[0022] Optionally, the step size of the AVC module is used to limit the adjustment range of reactive power, denoted as ΔQ. step =η·Q rated Where η represents the step size ratio, Q rated ​This represents the rated reactive power capacity of the inverter or reactive power compensation device at the corresponding photovoltaic power generation grid connection point.

[0023] Optionally, the constraints of the anti-backflow module include:

[0024] a. The inverter at the photovoltaic power generation grid connection point automatically exits anti-reverse current control when communication is interrupted;

[0025] b. When the inverter at each photovoltaic power generation grid connection point is adjusted to its limit, the AGC adjustment function will be suspended and an alarm will be triggered.

[0026] In summary, the present invention has the following beneficial effects:

[0027] 1. The system scheduling module can issue scheduling commands for dynamic allocation of active power by AGC and reactive power collaborative compensation by AVC, which greatly improves the voltage control accuracy and frequency response speed of photovoltaic power generation, thereby improving grid stability and power quality of photovoltaic power generation, and further increasing the adaptability of scenarios.

[0028] 2. The system has strong equipment access capabilities, supports the access and control of large-scale photovoltaic power generation equipment, and can adjust the control priority of different photovoltaic equipment according to actual needs, thereby meeting the equipment control requirements of actual scenarios and further realizing the dynamic self-adaptation and intelligence of the system.

[0029] 3. The system scheduling module intelligently filters active or reactive power adjustment needs through real-time deviation monitoring, threshold triggering mechanism and dynamic priority adjudication, further improving the system's scenario adaptability. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the main logic flow of the system of the present invention;

[0031] Figure 2 This is a schematic diagram of the logic flow of the AGV active power regulation module of the present invention;

[0032] Figure 3 This is a schematic diagram of the logic flow of the AVC reactive power regulation module of the present invention. Detailed Implementation

[0033] To make the objectives, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0034] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0035] In this invention, unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. The terms "vertical," "horizontal," "left," "right," "above," "below," and similar expressions are for illustrative purposes only and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0036] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] This invention provides a photovoltaic power generation management, control, and regulation system, such as... Figure 1As shown, it includes: a data acquisition module, installed at the grid-connected node of the photovoltaic power generation system, used to collect and transmit various operational data of the grid-connected node in real time; a system scheduling module, which, based on the photovoltaic grid-connected power adjustment issued by the power grid dispatching center and the data transmitted by the data acquisition module, determines whether regulation is needed, and then issues active power scheduling instructions and / or reactive power scheduling instructions for the photovoltaic power generation system based on the regulation conditions; an AGC active power regulation module, which dynamically adjusts the active power output of the inverter through a priority allocation strategy based on the active power scheduling instructions, thereby adjusting the grid-connected power of the photovoltaic grid-connected node; an AVC reactive power regulation module, which coordinates the reactive power output of the reactive power compensation device and the inverter based on the reactive power scheduling instructions, thereby adjusting the grid-connected voltage of the photovoltaic power generation system's grid-connected node; and a dynamic response module, used to monitor the frequency fluctuations of the photovoltaic power grid and generate dynamic regulation instructions using virtual synchronous machine control and fuzzy PID regulation.

[0038] Specifically, the control conditions of the system scheduling module are deviation threshold and dynamic adjustment of the power grid status;

[0039] In Example 1, when ΔP > 2%P rated In the case of active power regulation, the triggering condition is met, and an active power dispatch command is issued; in other embodiments, when the photovoltaic power generation grid has a frequency deviation, and |Δf|>0.5Hz, AGC active power regulation is executed first, and an active power dispatch command is also issued.

[0040] In Example 2, when ΔQ > 3%Q rated In the case of a situation where the reactive power regulation trigger condition is met, a reactive power dispatch command is issued; in other embodiments, when a voltage deviation occurs in the photovoltaic power generation grid and |ΔU|> jitter range, AVC reactive power regulation is executed first.

[0041] In Example 3, during the steady-state operation of the photovoltaic power grid, a hybrid regulation scheme combining AGC active power regulation and AVC reactive power regulation is adopted. The regulation weight ratio is expressed as ΔP. final =w AGC ·ΔP AGC +w AVC ·ΔP AVC ΔQ final =w AVC ·ΔQ AVC +w AGC ·ΔQ AGC Active power dispatch instructions and reactive power dispatch instructions are issued according to the above weighting ratios; the target value of active power is expressed as P. target =P base ±ΔP adjust , where P base The reference power value, ΔP, is expressed as the power value under the current operating conditions. adjustThe adjustment amount, generated based on scheduling requirements or predictive models, can be manually set or automatically generated by the system based on historical operating conditions; the voltage target value is represented as U. target =U nominal ±ΔU adjust U nominal Represented as rated voltage, ΔU adjust The voltage deviation is expressed as a value that can be manually set or automatically generated by the system based on historical operating conditions; the reactive power target value is expressed as Q. target =Q base ±ΔQ adjust Q base Based on the reactive power demand of the power grid or historical data, Q is set. adjust It is represented as reactive power deviation, which can be set manually or automatically generated by the system based on historical operating status.

[0042] In other embodiments, to ensure the minimization of overall adjustment costs and to better suit actual application scenarios, for example, AGC has a higher weight in frequency-sensitive scenarios and AVC has a higher weight in voltage-sensitive scenarios, an optimization objective function is adopted, expressed as min(α·|Δf|+β·|ΔU|), where α represents the frequency priority coefficient and β represents the voltage priority coefficient.

[0043] In Example 4, when the system scheduling module receives an order from the power grid dispatch center to increase / decrease the photovoltaic grid-connected power, the system scheduling module increases the adjustment weight of AGC regulation to 0.9 and decreases the adjustment weight of AVC regulation to 0.1 to ensure that active power regulation is executed first, denoted as ΔP. final =w AGC ·ΔP AGC +w AVC ·ΔP AVC , where ΔP AGC =P target，new -P now Then, an active power dispatch command is issued; when active power adjustment is performed, if |ΔU|> jitter interval is detected, the AVC compensation mode is activated and a reactive power dispatch command is issued.

[0044] Specifically, the jitter range mentioned above can be automatically generated by the system based on historical working conditions or set manually. In this embodiment, the jitter range is ±0.5%.

[0045] Furthermore, the AGC active power regulation module includes: a first instruction receiving unit, used to receive active power scheduling instructions issued by the system scheduling module, and then parse out the total active power target value; a first scheduling calculation unit, used to receive data transmitted by the data acquisition module and data transmitted by the first instruction receiving unit to calculate the regulation target correction value; a first strategy allocation unit, used to generate and transmit power increase regulation strategy instructions or power decrease regulation strategy instructions according to the calculation results of the first scheduling calculation unit; and a first instruction issuing unit, used to issue the regulation instructions generated by the first strategy allocation unit to the inverters of the grid-connected nodes of the photovoltaic power generation system in batches, and monitor the regulation results. If the target value is not reached, a fine-tuning mechanism is triggered.

[0046] Furthermore, the AVC reactive power regulation module includes: a second instruction receiving unit, used to receive reactive power scheduling instructions issued by the system scheduling module, and then parse out the voltage target value or reactive power target value; a second scheduling calculation unit, used to receive data transmitted by the data acquisition module and data transmitted by the second instruction receiving unit to generate reactive power regulation strategy instructions; and a second instruction issuing unit, used to issue the reactive power regulation strategy instructions generated by the second scheduling calculation unit to the equipment of the grid-connected node of the photovoltaic power generation system in steps.

[0047] Furthermore, the dynamic response module includes: a virtual synchronous machine control unit, which simulates the inertial response characteristics of a synchronous generator based on the data collected by the data acquisition module, thereby stabilizing the photovoltaic power grid frequency; a fuzzy PID power smoothing control unit, which suppresses power step changes caused by sudden changes in illumination, thereby stabilizing the photovoltaic power grid power; and a multi-objective coordination logic unit, which coordinates the outputs of the virtual synchronous machine and the fuzzy PID, and issues the dynamic adjustment command after coordination to avoid control conflicts.

[0048] In a specific embodiment, the data acquisition module receives the grid frequency f, grid connection point voltage U, and photovoltaic array output power P. PV Load power P load and energy storage SOC;

[0049] The virtual synchronizer control unit calculates the virtual inertia based on the received data, and expresses it as follows: Where Δf represents the change in frequency deviation, Δf = f 实际 -f 额定 Δt represents the frequency change time window, which defaults to 1 second; based on the calculated virtual inertia, the power adjustment is calculated and expressed as... in It is represented as a frequency change, and based on the power adjustment, an increase / decrease active power command is generated and transmitted to the multi-objective coordination logic unit.

[0050] The fuzzy PID power smoothing control unit calculates the power deviation e(t) and the deviation change rate de / dt based on the received data. The calculated results are mapped to fuzzy linguistic variables, and K is dynamically adjusted according to the fuzzy linguistics. p K i K d K p K represents the proportionality coefficient of the controller's response to the current power deviation e(t). i K represents the controller's ability to correct for historical accumulated errors, expressed as the integral coefficient that eliminates steady-state errors through the integral term. d This represents the differential coefficient of the controller's ability to predict and suppress the rate of change of power deviation, de / dt; when expressed in fuzzy language as a large e(t) and a large de / dt, the output K increases significantly. p Slightly increase K d Maintain K i The control command is given to adjust the PID parameters, and then the adjustment amount is calculated. The adjustment amount is then used to generate adjustment instructions, which are transmitted to the multi-objective coordination logic unit. When the fuzzy language representation is that e(t) is small and de / dt is negative, the output decreases by K. p Increase K d Decrease K i The control command is given to the PID parameter adjustment, then the adjustment amount is calculated, and the adjustment amount is generated into a control command and transmitted to the multi-objective coordination logic unit; by dynamically adjusting the ratio of the three through fuzzy logic, the photovoltaic system can achieve a balance between fast response and stable operation, and finally achieve a smooth output with a power change rate of ≤5% / s, which meets the grid connection requirements;

[0051] After receiving the adjustment commands from the virtual synchronous machine control unit and the fuzzy PID power smoothing control unit, the multi-objective coordination logic unit issues the commands according to priority. The priority decision rule is as follows: when |Δf|>0.5Hz, VSG frequency adjustment is executed first, and PID power smoothing is paused; if dP / dt>5% / s, fuzzy PID is started first; when VSG and PID need to be adjusted simultaneously, the final command is allocated according to weight, represented as ΔP. final =0.7·ΔP VSG +0.3·ΔP PID The final instruction is sent sequentially to devices with the highest priority status, according to the step size.

[0052] The multi-target coordination logic unit simultaneously detects the actual power P. actual If the actual power after adjustment does not meet the standard, a fine-tuning command is used to further improve the adjustment effect, which is represented as... Compared to traditional control methods, existing technologies do not have the collaborative control of virtual inertial response and fuzzy PID, and reactive power distribution only relies on the inverter, without involving the hybrid algorithm of SVC / SVG devices. The innovative control method can significantly improve the frequency control accuracy and further adapt to actual application scenarios.

[0053] Specifically, the aforementioned proportionality coefficient K p ∈[0.5,1.2], integral coefficient K i ∈[0.1,0.3], differential coefficient K d ∈[0.05,0.15], with a power change rate limit of ≤5% / s.

[0054] Furthermore, it also includes: an anti-reverse current module for predicting the reverse power trend of the photovoltaic power grid and executing multi-level interlocking protection actions; the anti-reverse current module includes: a reverse power calculation unit, which calculates the real-time reverse power value and the reverse power value in the future time period based on the data transmitted by the data acquisition module, thereby obtaining the real-time reverse power value and the reverse power prediction value, and comparing them with the corresponding reverse power threshold to generate a first-level protection command or a second-level protection command for transmission; a multi-level interlocking protection execution unit, which can be used to adjust the inverter output power to 90% of the load demand when receiving the first-level protection command, thereby achieving rapid adjustment protection; or it can be used to disconnect the grid-connected contactor and start the energy storage charging or unloading device when receiving the second-level protection command, thereby achieving the protection effect; an alarm and feedback unit, which pushes alarm information to the monitoring interface in real time, synchronously generates an event log, and records the triggering event, protection level and equipment status.

[0055] In a specific embodiment, the current direction I at the grid connection point is collected in real time by the data acquisition module. dir Active power P grid and reactive power Q gridt It also acquires the real-time operating status of the inverter at the grid connection point and the inverter's output power P. inv and the SOC and grid connection status of the energy storage system;

[0056] Real-time inverse power calculation: Calculate the net power, expressed as P. net =P inv -P load , where P load This is expressed as the real-time power of the load; if P net If the value is less than 0, it is determined to be reverse power, and the real-time reverse power value is expressed as P. reverse =|P net |;

[0057] Inverse power prediction: The future inverse power value is predicted and calculated using a Kalman filter prediction model, expressed as: State equation x k =Ax k-1+Bu k +w k Observation equation z k =Hx k +v k , where x k Represented as system state (system inverse power trend), w k and v k Represented as process noise and observation noise, u k This is represented as control input (changes in illumination, changes in load); in practical applications, the inverse power prediction value is updated based on the Kalman filter prediction model, and is represented as... In this embodiment, to predict the change in inverse power trend over the next 10 seconds, wherein Represented as the inverse power prediction value, P reverse It is expressed as the real-time inverse power value, and α and β represent the dynamic coefficients;

[0058] Multi-level protection action triggering, Level 1 protection: when the reverse power calculation unit calculates the real-time reverse power value P reverse >5%P rated Or inverse power prediction value If the grid connection point is determined to be in a risky state, a first-level protection command is generated and transmitted to the multi-level interlocking protection execution unit.

[0059] After receiving the first-level protection command, the multi-level interlocking protection execution unit adjusts the inverter's output power, denoted as P. inv_new =max(P load ×90%, P inv -ΔP step ), where ΔP step The single adjustment step size is expressed as ΔP. step =2%P rated After adjustment, monitor the reverse power in real time. If P reverse If the value is still above the threshold, the secondary protection command will be executed automatically.

[0060] Secondary protection: When the reverse power calculation unit calculates the real-time reverse power value P reverse >10%P rated When the duration is greater than 1 second, a secondary protection command is generated and transmitted to the multi-level interlocking protection execution unit.

[0061] After receiving the secondary protection command, the multi-level interlocking protection execution unit controls the disconnection of the grid-connected contactor and simultaneously starts energy storage charging, represented as P. charge =min(P reverse ,P ESS_max SOC available ), where P ESS_max State of Charge (SOC) represents the maximum charging power of the energy storage system. available=1-SOC current SOC current This represents the current energy storage status of the SOC;

[0062] During the adjustment process of the multi-level interlocking protection execution unit, if the inverter communication is interrupted or the adjustment is reached to the limit (P) inv <5%P rated The control measures will be suspended and an alarm will be sent to prompt management personnel to reissue the control instructions.

[0063] The alarm and feedback unit records event data (trigger time, reverse power value, protection action type) and generates reports for operation and maintenance analysis.

[0064] Furthermore, the specific execution steps of the AGC active power regulation module are as follows:

[0065] Step A: The first instruction receiving unit receives the active power scheduling instruction issued by the system scheduling module, and then parses out the total active power target value P in the active power scheduling instruction. target And simultaneously check whether it is within the adjustable range of the photovoltaic power grid;

[0066] Step B: Based on the total active power target value, perform target value correction, and then use the corrected control target value, denoted as P, for control. ntarget =P target +∑P inow -P now , where ∑P inow It represents the sum of the real-time power of all inverters participating in the regulation, and n represents the number of grid-connected nodes of the photovoltaic power generation system participating in the regulation;

[0067] Step C: The first strategy allocation unit is based on the power difference, represented as P. AGC =P ntarget -P now When P AGC When P > 0, a power increase adjustment strategy instruction is generated; when P AGC If <0, generate a power reduction adjustment strategy instruction;

[0068] Step D: The first instruction issuing unit divides the received power increase or power decrease adjustment strategy instructions into steps and issues them in batches to the inverters of each grid-connected node of the photovoltaic power generation system. When it is a power increase adjustment strategy instruction, it is allocated from high to low priority according to the inverters of the grid-connected node of the photovoltaic power generation system, as shown in step D. When the power reduction regulation strategy command is issued, it is allocated according to the priority status of the inverters at the grid-connected nodes of the photovoltaic power generation system from low to high, as represented as:

[0069] Step E: The first instruction issuing unit synchronously monitors the control results. If the target value is not reached, a fine-tuning mechanism is triggered, indicating that... Where K adjust It is represented as the control coefficient.

[0070] Furthermore, the specific execution steps of the AVC reactive power regulation module are as follows:

[0071] Step A: The second instruction receiving unit receives the reactive power scheduling instruction issued by the system scheduling module, and then parses out the reactive power target value Q in the reactive power scheduling instruction. target and voltage target value U target ;

[0072] Step B: The second scheduling calculation unit receives the real-time voltage value U of each photovoltaic power generation system's grid-connected node collected by the data acquisition module. mea reactive power Q mea SVC / SVG equipment operating status and inverter no-function capacity Q at grid connection point gimax ;

[0073] Step C: The second scheduling calculation unit calculates the reactive power regulation strategy instructions, wherein the reactive power regulation strategy instructions include a first reactive power regulation instruction, a second reactive power regulation instruction, and a third reactive power regulation instruction; when Q target ≤λQ svg In this case, it means that only the SVC / SVG device is responsible, only the output target voltage of the SVC / SVG device is adjusted, the first reactive power regulation command is generated and transmitted; when λQ svg target ≤λQ svg +∑Q gimax In this case, the reactive power difference of the inverter is preferentially allocated, denoted as ΔQ. g =Q target -λQ svg The remaining reactive power difference is compensated by the SVC / SVG device, generating a second reactive power adjustment command and transmitting it; when Q target Q svg +∑Q gimax In this case, it means that the reactive power output value of the inverter is adjusted to Q. gimax The voltage value of SVC / SVG equipment is according to U target Adjustment is performed, at which point the adjustment limit has been triggered, generating a third reactive power adjustment command and an over-limit alarm warning, which are transmitted synchronously; where λ represents the weighting coefficient.

[0074] Step D: The second instruction issuing unit receives the first reactive power adjustment instruction, the second reactive power adjustment instruction, or the third reactive power adjustment instruction, and issues the corresponding adjustment instruction to the corresponding equipment according to the step size to complete the reactive power adjustment. ​

[0075] Optionally, the step size controlled in the AGC module means limiting the adjustment range of active power, denoted as ΔP. step =η·P rated Where η represents the step size ratio, P rated This is expressed as the rated active power of the inverter at the corresponding photovoltaic power generation grid connection point.

[0076] Specifically, the step size ratio η is 1%-5%, and the step size waiting period is 5s-30s.

[0077] Optionally, the step size of the AVC module is used to limit the adjustment range of reactive power, denoted as ΔQ. step =η·Q rated Where η represents the step size ratio, Q rated This represents the rated reactive power capacity of the inverter or reactive power compensation device at the corresponding photovoltaic power generation grid connection point.

[0078] Specifically, the step size ratio η is 1%-5%, and the step size waiting period is 5s-30s.

[0079] This invention discloses a photovoltaic power generation management and control system. Through the system scheduling module, scheduling commands can be issued to allocate AGC active power dynamic allocation and AVC reactive power collaborative compensation, which greatly improves the voltage control accuracy and frequency response speed of photovoltaic power generation, thereby enhancing grid stability and photovoltaic power quality, and further increasing scenario adaptability. The system has strong equipment access capabilities, supports the access and control of large-scale photovoltaic power generation equipment, and can adjust the control priority of different photovoltaic equipment according to actual needs, thereby meeting the equipment control requirements of actual scenarios, and further realizing the dynamic self-adaptation and intelligence of the system.

[0080] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A photovoltaic power generation management, control, and regulation system, characterized in that, include: The data acquisition module is installed at the grid-connected node of the photovoltaic power generation system to collect and transmit various operating data of the grid-connected node in real time. The system scheduling module determines whether regulation is needed based on the photovoltaic grid-connected power adjustment instructions issued by the power grid dispatching station and the data transmitted by the data acquisition module, and then issues active power scheduling instructions and / or reactive power scheduling instructions for the photovoltaic power generation system based on the regulation conditions. The AGC active power regulation module dynamically adjusts the active power output of the inverter based on the active power scheduling instructions and a priority allocation strategy, thereby adjusting the grid-connected power of the photovoltaic grid connection point. The AVC reactive power regulation module coordinates the distribution of reactive power output between the reactive power compensation device and the inverter based on reactive power dispatch instructions, thereby regulating the grid-connected voltage of the photovoltaic power generation system's grid-connected nodes. The dynamic response module is used to monitor the frequency fluctuations of the photovoltaic power grid and generate dynamic adjustment commands using virtual synchronous machine control and fuzzy PID regulation. The dynamic response module includes: The virtual synchronous machine control unit, based on the data collected by the data acquisition module, simulates the inertial response characteristics of a synchronous generator, thereby stabilizing the frequency of the photovoltaic power grid. Fuzzy PID power smoothing control unit is used to suppress power step changes caused by sudden changes in sunlight, thereby stabilizing the power of photovoltaic power generation grid; The multi-objective coordination logic unit is used to coordinate the outputs of the virtual synchronizer and the fuzzy PID, and then issues the dynamic adjustment command after coordination to avoid control conflicts. It also includes: an anti-reverse current module for predicting the reverse power trend of the photovoltaic power grid and executing multi-level interlocking protection actions; The anti-backflow module includes: a reverse power calculation unit, which calculates the real-time reverse power value and the reverse power value in the future time period based on the data transmitted by the data acquisition module, thereby obtaining the real-time reverse power value and the reverse power prediction value, and comparing them with the corresponding reverse power threshold to generate a first-level protection command or a second-level protection command for transmission; The multi-level interlocking protection execution unit can be used to adjust the inverter output power to 90% of the load demand when receiving the first-level protection command, thereby achieving rapid adjustment protection; or it can be used to disconnect the grid-connected contactor and start the energy storage charging or unloading device when receiving the second-level protection command, thereby achieving the protection effect. The alarm and feedback unit pushes alarm information to the monitoring interface in real time and generates event logs simultaneously, recording triggering events, protection levels, and device status.

2. The photovoltaic power generation management, control and regulation system according to claim 1, characterized in that, The AGC active power regulation module includes: The first instruction receiving unit is used to receive the active power scheduling instruction issued by the system scheduling module, and then parse out the total active power target value. The first scheduling calculation unit is used to receive data transmitted by the data acquisition module and data transmitted by the first instruction receiving unit to calculate the adjustment target correction value. The first strategy allocation unit is used to generate and transmit power increase adjustment strategy instructions or power decrease adjustment strategy instructions based on the calculation results of the first scheduling calculation unit. The first instruction issuing unit is used to issue the adjustment instructions generated by the first strategy allocation unit to the inverters of the grid-connected nodes of the photovoltaic power generation system in batches, and monitor the control results. If the target value is not reached, the fine-tuning mechanism is triggered.

3. The photovoltaic power generation management, control, and regulation system according to claim 1, characterized in that, The AVC reactive power regulation module includes: The second instruction receiving unit is used to receive the reactive power scheduling instruction issued by the system scheduling module, and then parse out the voltage target value or reactive power target value. The second scheduling calculation unit is used to receive data transmitted by the data acquisition module and data transmitted by the second instruction receiving unit to generate reactive power adjustment strategy instructions. The second instruction issuing unit is used to issue reactive power regulation strategy instructions generated by the second scheduling calculation unit to the equipment of the grid-connected node of the photovoltaic power generation system in steps.

4. The photovoltaic power generation management, control and regulation system according to claim 2, characterized in that, The step size in the AGC active power regulation module refers to the limit on the adjustment range of active power, expressed as: ,in Expressed as step size ratio, This is expressed as the rated active power of the inverter at the corresponding photovoltaic power generation grid connection point.

5. The photovoltaic power generation management, control, and regulation system according to claim 3, characterized in that, The step size in the AVC reactive power regulation module refers to the limit of the reactive power regulation range, expressed as: ,in Expressed as step size ratio, This represents the rated reactive power capacity of the inverter or reactive power compensation device at the corresponding photovoltaic power generation grid connection point.

6. The photovoltaic power generation management, control and regulation system according to claim 1, characterized in that, The constraints of the anti-backflow module include: a. The inverter at the photovoltaic power generation grid connection point automatically exits anti-reverse current control when communication is interrupted; b. When the inverter at each photovoltaic power generation grid connection point is adjusted to its limit, the AGC adjustment function will be suspended and an alarm will be triggered.

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