Photovoltaic power generation management control adjusting system

Abstract

The invention relates to the technical field of photovoltaic power generation management systems, in particular to a photovoltaic power generation management, control and regulation system, which realizes multi-target collaborative optimization by fusing AGC active dynamic distribution, AVC reactive collaborative compensation, virtual inertia frequency response and reverse power rapid protection technologies. The system adopts a priority regulation and control strategy, a hybrid reactive power distribution algorithm and a multi-stage interlocking protection mechanism, the stability and the regulation precision of the power grid are remarkably improved, and the grid-connected requirement of a large-scale photovoltaic power station is met.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic management systems, and more specifically, it relates to a photovoltaic power generation management control and regulation system. Background Art

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

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

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a photovoltaic power generation management control and regulation system to solve the problems existing in the above background art.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: A photovoltaic power generation management control and regulation system, a data acquisition module, is arranged at the grid connection node of the photovoltaic power generation system for collecting and transmitting various operation data of the grid connection point in real time; a system scheduling module, based on the photovoltaic grid connection power adjustment issued by the grid dispatching center and the data transmitted by the data acquisition module, judges 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, based on the active power scheduling instructions, dynamically adjusts the active power output of the inverter through a priority allocation strategy, and then adjusts the grid connection power of the photovoltaic grid connection point; an AVC reactive power regulation module, based on the reactive power scheduling instructions, collaboratively allocates the reactive power output of the reactive power compensation device and the inverter, and then adjusts the grid connection voltage of the grid connection node of the photovoltaic power generation system; a dynamic response module, for monitoring the frequency fluctuation of the photovoltaic power generation grid and generating dynamic regulation instructions by using virtual synchronous machine control and fuzzy PID regulation.

[0006] Optionally, the AGC active power regulation module includes: a first instruction receiving unit, configured to receive the active power scheduling instruction issued by the system scheduling module, and then parse out the total active power target value; a first scheduling calculation unit, configured to receive the data transmitted by the data acquisition module and the data transmitted by the first instruction receiving unit to calculate the regulation target correction value; a first policy allocation unit, configured to generate an active power increase regulation strategy instruction or an active power decrease regulation strategy instruction according to the calculation result of the first scheduling calculation unit and transmit it; a first instruction issuing unit, configured to batch-issue the regulation instruction generated by the first policy allocation unit to the inverters at the grid connection nodes of the photovoltaic power generation system, and monitor the regulation result. 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, configured to receive the reactive power scheduling instruction issued by the system scheduling module, and then parse out the voltage target value or the reactive power target value; a second scheduling calculation unit, configured to receive the data transmitted by the data acquisition module and the data transmitted by the second instruction receiving unit to generate a reactive power regulation strategy instruction; a second instruction issuing unit, configured to stepwise issue the reactive power regulation strategy instruction generated by the second scheduling calculation unit to the devices at the grid connection nodes of the photovoltaic power generation system.

[0008] Optionally, the dynamic response module includes: a virtual synchronous machine control unit, which, based on the data collected by the data acquisition module, simulates the inertia response characteristics of a synchronous generator to stabilize the frequency of the photovoltaic power grid; a fuzzy PID power smoothing control unit, configured to suppress the power step change caused by sudden changes in light to stabilize the power of the photovoltaic power grid; a multi-objective coordination logic unit, configured to coordinate the outputs of the virtual synchronous machine and the fuzzy PID, and issue the dynamic regulation instruction after coordination to avoid control conflicts.

[0009] Optionally, it further includes: a reverse power flow prevention module for predicting the reverse power trend of the photovoltaic power grid and performing multi-level interlock protection actions; the reverse power flow prevention module includes: a reverse power calculation unit, which, based on the data transmitted by the data acquisition module, calculates the real-time reverse power value and the reverse power value within a future time period, and then obtains the real-time reverse power value and the reverse power prediction value, and compares them with the corresponding reverse power thresholds to generate a first-level protection instruction or a second-level protection instruction for transmission; a multi-level interlock protection execution unit, which can be used to adjust the output power of the inverter to 90% of the load demand when receiving the first-level protection instruction to achieve rapid adjustment and protection; or can be used to disconnect the grid connection contactor and start the energy storage charging or discharging device when receiving the second-level protection instruction to achieve the protection effect; an alarm and feedback unit, which real-time pushes alarm information to the monitoring interface and synchronously generates an event log to record the triggering event, protection level, and device 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 target in the active power scheduling instruction, and simultaneously checks whether it is within the adjustable range value of the photovoltaic power generation power grid;

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

[0013] Step C: The first strategy allocation unit, based on the power difference, expressed as P AGC =P ntarget -P now When P AGC >0, generate an increased power regulation strategy instruction; when P AGC <0, generate a decreased power regulation strategy instruction;

[0014] Step D: The first instruction issuing unit divides the received increased power regulation strategy instruction or decreased power regulation strategy instruction by the step size and issues it to the inverters at the grid-connected nodes of each photovoltaic power generation system in batches; when it is an increased power regulation strategy instruction, it is allocated from high to low according to the priority status of the inverters at the grid-connected nodes of the photovoltaic power generation system, expressed as When it is a decreased power regulation strategy instruction, it is allocated from low to high according to the priority status of the inverters at the grid-connected nodes of the photovoltaic power generation system, expressed as

[0015] Step E: The first instruction issuing unit synchronously monitors the regulation result. If the target value is not reached, trigger the fine-tuning mechanism, expressed as where K adjust represents the regulation 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 target and the voltage target value U target ;

[0018] Step B. The second scheduling calculation unit receives the real-time voltage value U of the grid-connected nodes of each photovoltaic power generation system collected by the data acquisition module mea , the reactive power value Q mea , the operating status of the SVC / SVG device and the reactive power capacity Q of the grid-connected point inverter gimax ;

[0019] Step C. The second scheduling calculation unit calculates the reactive power regulation strategy instruction, where the reactive power regulation strategy instruction includes a first reactive power regulation instruction, a second reactive power regulation instruction, and a third reactive power regulation instruction; when Q target ≤λQ svg , it means that only the SVC / SVG device undertakes the regulation, and only the output target voltage of the SVC / SVG device is adjusted to generate a first reactive power regulation instruction and transmit it; when λQ svg <Q target ≤λQ svg +∑Q gimax , it means that the reactive power difference of the inverter is preferentially allocated, expressed as ΔQ g =Q target -λQ svg , and the remaining reactive power difference is compensated by the SVC / SVG device to generate a second reactive power regulation instruction and transmit it; when Q target >Q svg +∑Q gimax , it means that the reactive power output value of the inverter is adjusted to Q gimax , and the voltage value of the SVC / SVG device is adjusted according to U target , and at this time, the adjustment upper limit has been triggered, and a third reactive power regulation instruction and an over-limit alarm warning are transmitted synchronously; where the above λ represents a weight coefficient;

[0020] Step D. The second instruction issuing unit receives the first reactive power regulation instruction, the second reactive power regulation instruction, or the third reactive power regulation instruction, and issues the corresponding regulation instruction to the corresponding device step by step to complete the reactive power regulation.

[0021] Optionally, the meaning of the regulation step length in the AGC module is to limit the regulation amplitude of the active power, expressed as ΔP step =η·P rated , where η represents the step length ratio, and P rated represents the rated active power of the inverter at the corresponding photovoltaic power generation grid-connected point.

[0022] Optionally, the meaning of the regulation step length in the AVC module is to limit the regulation amplitude of the reactive power, expressed as ΔQ step =η·Q rated , where η represents the step length ratio, and Q ratedIt represents the rated reactive power capacity of the inverter or reactive power compensation device corresponding to the grid connection point of photovoltaic power generation.

[0023] Optionally, the constraint conditions of the anti-counterflow module include:

[0024] a. When the communication of the inverter at the grid connection point of photovoltaic power generation is interrupted, the anti-counterflow regulation automatically exits.

[0025] b. When the inverters at each grid connection point of photovoltaic power generation are adjusted to the limit, the AGC regulation function is suspended and an alarm is given.

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

[0027] 1. Through the system scheduling module, scheduling instructions for allocating AGC active power dynamic distribution and AVC reactive power collaborative compensation can be issued, which greatly improves the voltage control accuracy and frequency response speed of photovoltaic power generation, thereby enhancing the grid stability and the power quality of photovoltaic power generation, and further increasing the scenario adaptability.

[0028] 2. The system has strong device access capabilities, supports the access regulation of a large number of photovoltaic power generation devices, and can set the regulation priorities of different photovoltaic devices according to actual conditions, thereby meeting the device regulation requirements of actual scenarios, and further realizing the dynamic self-adaptation and intelligence of the system.

[0029] 3. The system scheduling module intelligently screens the active or reactive power regulation requirements through real-time deviation monitoring, threshold triggering mechanism and dynamic priority adjudication, further improving the scenario adaptability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0032] Figure 3 It is a schematic diagram of the logical flow of the AVC reactive power regulation module of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] In order to make the objectives, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is given 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 the present invention, unless otherwise clearly specified or limited, terms such as "installed", "connected", "coupled", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0035] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature. Terms such as "vertical", "horizontal", "left", "right", "up", "down" and similar expressions are only for the purpose of illustration, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operate in a specific orientation, and thus cannot be understood as a limitation to the present invention.

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

[0037] The present invention provides a photovoltaic power generation management control and regulation system, as Figure 1As shown in the figure, it includes: a data acquisition module, which is set at the grid connection node of the photovoltaic power generation system and is used to collect and transmit various operating data of the real-time grid connection point; a system scheduling module, which judges whether regulation is needed based on the photovoltaic grid connection power adjustment issued by the grid dispatching station and the data transmitted by the data acquisition module, and then issues an active power scheduling instruction and / or a reactive power scheduling instruction for the photovoltaic power generation system based on the regulation conditions; an AGC active power regulation module, which dynamically regulates the active power output of the inverter through a priority allocation strategy based on the active power scheduling instruction, and then regulates the grid connection power of the photovoltaic grid connection point; an AVC reactive power regulation module, which coordinates and distributes the reactive power output of the reactive power compensation device and the inverter based on the reactive power scheduling instruction, and then regulates the grid connection voltage of the grid connection node of the photovoltaic power generation system; a dynamic response module, which is used to monitor the frequency fluctuation of the photovoltaic power generation grid and generate a dynamic regulation instruction by using virtual synchronous machine control and fuzzy PID regulation.

[0038] Specifically, the regulation condition of the system scheduling module is the deviation threshold and the dynamic adjustment of the grid state;

[0039] In Embodiment 1, when ΔP > 2%P rated the triggering condition for active power regulation is reached, and an active power scheduling instruction is issued; in other embodiments, when there is a frequency deviation in the photovoltaic power generation grid, |Δf| > 0.5 Hz, AGC active power regulation is preferentially executed, and an active power scheduling instruction is also issued;

[0040] In Embodiment 2, when ΔQ > 3%Q rated the triggering condition for reactive power regulation is reached, and a reactive power scheduling instruction is issued; in other embodiments, when there is a voltage deviation in the photovoltaic power generation grid, |ΔU| > the jitter range, AVC reactive power regulation is preferentially executed;

[0041] In Embodiment 3, during the steady-state operation of the photovoltaic power generation grid, a hybrid regulation scheme of AGC active power regulation and AVC reactive power regulation is adopted, and 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 scheduling instructions and reactive power scheduling instructions are issued according to the above weight ratio; the active power target value is expressed as P target = P base ±ΔP adjust where P base represents the reference power value under the current working condition, and ΔP adjustIt is the adjustment amount generated according to the dispatch demand or prediction model, which can be set manually or automatically generated by the system according to the historical operating status; the voltage target value is expressed as U target =U nominal ±ΔU adjust , where U nominal Expressed as rated voltage, ΔU adjust It is expressed as voltage deviation, which can be set manually or automatically generated by the system based on historical operating status; the reactive power target value is expressed as Q target =Q base ±ΔQ adjust , where Q base Based on the grid reactive power demand or historical data setting, Q adjust It is expressed as reactive deviation, which can be set manually or automatically generated by the system based on historical operating status;

[0042] In other embodiments, to minimize the comprehensive regulation cost and to better conform to actual application scenarios, for example, in frequency-sensitive scenarios, the AGC weight is higher; in voltage-sensitive scenarios, the AVC weight is higher, and an optimization objective function is adopted, which is expressed as min(α·|Δf|+β·|ΔU|), where α represents the frequency priority coefficient and β represents the voltage priority coefficient.

[0043] In the fourth embodiment, when the system dispatch module receives the increase / decrease of photovoltaic grid-connected power from the grid dispatching station, the system dispatch module increases the adjustment weight of AGC regulation to 0.9 and reduces the adjustment weight of AVC regulation to 0.1 to ensure that active power regulation is executed first, which is expressed as ΔP final =w AGC ΔP AGC +w AVC ΔP AVC , where ΔP AGC =P target，new -P now , and then issue active power dispatch instructions; in the case of active power regulation, if |ΔU|> jitter interval is detected, the AVC compensation mode is started and reactive power dispatch instructions are issued.

[0044] Specifically, the jitter interval can be automatically generated by the system according to historical working conditions or manually set. In this embodiment, the jitter interval is selected as ±0.5%.

[0045] Furthermore, the AGC active power regulation module includes: a first instruction receiving unit for receiving the active power scheduling instruction issued by the system scheduling module and then parsing out the total active power target value; a first scheduling calculation unit for receiving the data transmitted by the data acquisition module and the data transmitted by the first instruction receiving unit to calculate the regulation target correction value; a first strategy allocation unit for generating an active power increase regulation strategy instruction or a power reduction regulation strategy instruction according to the calculation result of the first scheduling calculation unit and transmitting it; a first instruction issuing unit for batch-issuing the regulation instruction generated by the first strategy allocation unit to the inverters at the grid connection nodes of the photovoltaic power generation system and monitoring the regulation result. 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 for receiving the reactive power scheduling instruction issued by the system scheduling module and then parsing out the voltage target value or the reactive power target value; a second scheduling calculation unit for receiving the data transmitted by the data acquisition module and the data transmitted by the second instruction receiving unit to generate a reactive power regulation strategy instruction; a second instruction issuing unit for step-by-step issuing the reactive power regulation strategy instruction generated by the second scheduling calculation unit to the devices at the grid connection nodes of the photovoltaic power generation system.

[0047] Furthermore, the dynamic response module includes: a virtual synchronous machine control unit that, based on the data collected by the data acquisition module, simulates the inertia response characteristics of a synchronous generator to stabilize the frequency of the photovoltaic power grid; a fuzzy PID power smoothing control unit for suppressing the power step change caused by sudden changes in light to stabilize the power of the photovoltaic power grid; a multi-objective coordination logic unit for coordinating the outputs of the virtual synchronous machine and the fuzzy PID, and issuing the dynamic regulation instruction after coordination to avoid control conflicts.

[0048] In a specific embodiment, the grid frequency f, the grid connection point voltage U, the output power P of the photovoltaic array PV , the load power P load and the energy storage SOC are acquired by receiving the data acquisition module;

[0049] Based on the received data, the virtual synchronous machine control unit calculates the virtual inertia, expressed as where Δf represents the frequency deviation change amount, Δf = f 实际 -f 额定 , and Δt represents the frequency change time window, which is defaulted to 1 s; based on the calculated virtual inertia, the power regulation amount is calculated, expressed as where represents the frequency change amount. An increase / decrease active power instruction is generated based on the power regulation amount 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, maps them to fuzzy language variables based on the calculation results, and dynamically adjusts K according to the fuzzy language. p , K i , K d , where K p represents the proportional coefficient indicating the response degree of the controller to the current power deviation e(t), K i represents the integral coefficient indicating the correction ability of the controller to the historical cumulative error and eliminating the steady-state error through the integral term, K d represents the differential coefficient indicating the prediction and suppression ability of the controller to the power deviation change rate de / dt; when the fuzzy language indicates that e(t) is large and de / dt is positive large, the output greatly increases K p , slightly increases K d , and maintains the regulation instruction of K i for PID parameter adjustment, and then calculates the adjustment amount and generates an adjustment instruction with the adjustment amount and transmits it to the multi-objective coordination logic unit; when the fuzzy language indicates that e(t) is small and de / dt is negative small, the output decreases K p , increases K d , decreases K i regulation instruction for PID parameter adjustment, then calculates the adjustment amount, and generates an adjustment instruction with the adjustment amount and transmits it 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 ≤ 5% / s, meeting the grid connection requirements;

[0051] After receiving the adjustment instructions from the virtual synchronous generator control unit and the fuzzy PID power smoothing control unit, the multi-objective coordination logic unit implements and distributes the instructions according to the priority. The priority adjudication rule is as follows. When |Δf| > 0.5Hz, the VSG frequency adjustment is preferentially executed and the PID power smoothing is suspended; if dP / dt > 5% / s, the fuzzy PID is preferentially started; when both VSG and PID need to be adjusted simultaneously, the final instruction is allocated according to the weight, expressed as ΔP final = 0.7·ΔP VSG + 0.3·ΔP PID , and the final instruction is sequentially distributed to the devices with high to low priority status in steps;

[0052] The multi-objective coordination logic unit simultaneously detects the actual power P actual . If the adjusted actual power does not meet the standard, the adjustment effect is further improved through a fine-tuning instruction, expressed as Compared with traditional regulation, the prior art does not have the coordinated control of virtual inertia response and fuzzy PID, and the reactive power distribution only depends on the inverter, without involving the hybrid algorithm of SVC / SVG equipment. The innovative regulation method can greatly improve the frequency control accuracy and further adapt to the actual application scenario.

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

[0054] Furthermore, it also includes: an anti-counterflow module for predicting the reverse power trend of the photovoltaic power generation grid and performing multi-level interlock protection actions; the anti-counterflow module includes: a reverse power calculation unit, which calculates the real-time reverse power value and the reverse power value within a future time period based on the data transmitted by the data acquisition module, and then obtains the real-time reverse power value and the reverse power prediction value, and compares them with the corresponding reverse power thresholds to generate a first-level protection instruction or a second-level protection instruction for transmission; a multi-level interlock protection execution unit, which can be used to adjust the output power of the inverter to 90% of the load demand when receiving the first-level protection instruction, so as to achieve rapid adjustment protection; or can be used to disconnect the grid-connected contactor and start the energy storage charging or discharging device when receiving the second-level protection instruction, so as to achieve 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 device status.

[0055] In a specific embodiment, the data acquisition module is used to collect the current direction I dir , active power P grid and reactive power Q gridt of the grid connection point in real time, and obtain the operating state of the grid connection point inverter, the output power P inv of the inverter, the SOC of the energy storage system and the grid connection switch state in real time;

[0056] Real-time reverse power calculation: Calculate the net power, expressed as P net = P inv - P load , where P load represents the real-time load power; if P net < 0, it is determined as reverse power, and the real-time reverse power value is expressed as P reverse = |P net |;

[0057] Reverse power prediction: Predict and calculate the future reverse power value through the Kalman filter prediction model, expressed as: state equation x k = Ax k-1+Bu k +w k The observation equation z k = Hx k + v k where x k represents the system state (system reverse power trend), w k and v k represent process noise and observation noise respectively, and u k represents the control input (light change, load change); in practical applications, the reverse power prediction value is updated based on the Kalman filter prediction model, expressed as In this embodiment, to predict the change in the reverse power trend within the next 10 s, where represents the reverse power prediction value, P reverse represents the real-time reverse power value, and α and β represent dynamic coefficients;

[0058] Multi-level protection action is triggered. Primary protection: When the reverse power calculation unit calculates that the real-time reverse power value P reverse > 5%P rated or the reverse power prediction value it is determined that the grid connection point is in a risk state, and a primary protection instruction is generated and transmitted to the multi-level interlocking protection execution unit;

[0059] After receiving the primary protection instruction, the multi-level interlocking protection execution unit adjusts the output power of the inverter, expressed as P inv_new = max(P load × 90%, P inv - ΔP step ), where ΔP step represents the single adjustment step size, expressed as ΔP step = 2%P rated ; after adjustment, the reverse power is monitored in real time. If P reverse is still higher than the threshold, the secondary protection instruction is automatically executed;

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

[0061] After receiving the secondary protection instruction, the multi-level interlocking protection execution unit controls the disconnection of the grid connection contactor, and at the same time starts the energy storage charging, expressed as P charge = min(P reverse , P ESS_max · SOC available ), where P ESS_max represents the maximum charging power of the energy storage, and SOC available= 1 - SOC current , SOC current represents the current energy storage situation of SOC;

[0062] During the adjustment process of the multi - level interlock protection execution unit, if the inverter communication is interrupted or adjusted to the limit (P inv < 5%P rated ), the regulation is suspended and an alarm is pushed to prompt the management personnel to re - issue the regulation instruction;

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

[0064] Further, 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 target in the active power scheduling instruction, and synchronously checks whether it is within the adjustable range value of the photovoltaic power generation grid;

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

[0067] Step C: The first strategy distribution unit is based on the power difference, expressed as P AGC = P ntarget - P now . When P AGC > 0, a power - increasing regulation strategy instruction is generated; when P AGC < 0, a power - decreasing regulation strategy instruction is generated;

[0068] Step D: The first instruction issuing unit divides the received power - increasing regulation strategy instruction or power - decreasing regulation strategy instruction by the step size and distributes it to the inverters of the grid - connected nodes of each photovoltaic power generation system in batches; when it is a power - increasing regulation strategy instruction, it is distributed from high to low according to the priority status of the inverters of the grid - connected nodes of the photovoltaic power generation system, expressed as When it is a power - decreasing regulation strategy instruction, it is distributed from low to high according to the priority status of the inverters of the grid - connected nodes of the photovoltaic power generation system, expressed as

[0069] Step E, the first instruction issuing unit synchronously monitors the regulation result. If the target value is not reached, a fine-tuning mechanism is triggered, expressed as where K adjust represents the regulation 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 dispatch instruction issued by the system dispatch module, and then parses out the reactive power target value Q target and the voltage target value U target ;

[0072] Step B, the second dispatch calculation unit receives the real-time voltage value U mea , reactive power value Q mea , SVC / SVG device operating status and the reactive power capacity Q gimax of the grid-connected point inverter collected by the data collection module;

[0073] Step C, the second dispatch calculation unit calculates the reactive power regulation strategy instruction, where the reactive power regulation strategy instruction includes the first reactive power regulation instruction, the second reactive power regulation instruction and the third reactive power regulation instruction; when Q target ≤λQ svg , it means that only the SVC / SVG device undertakes the regulation, and only the output target voltage of the SVC / SVG device is regulated to generate the first reactive power regulation instruction and transmit it; when λQ svg <Qk target ≤λQ svg +∑Q gimax , it means that the reactive power difference of the inverter is preferentially allocated, expressed as ΔQ g =Q[[ID=4i]] target -λQ svg , and the remaining reactive power difference is compensated by the SVC / SVG device to generate the second reactive power regulation instruction and transmit it; when Q target >Q svg +∑Q gimax , it means that the reactive power output value of the inverter is adjusted to Q gimax , and the voltage value of the SVC / SVG device is adjusted according to U target . At this time, the adjustment upper limit has been triggered, and the third reactive power regulation instruction and the over-limit alarm warning are synchronously transmitted; among them, the above λ represents the weight coefficient;

[0074] Step D, the second instruction issuing unit receives the first reactive power regulation instruction, the second reactive power regulation instruction or the third reactive power regulation instruction, and issues the corresponding regulation instruction to the corresponding device step by step to complete the reactive power regulation.

[0075] Optionally, the meaning of the regulation step size in the AGC module is to limit the adjustment range of the active power, expressed as ΔP step = η·P rated , where η represents the step size ratio, and P rated represents the rated active power of the inverter at the corresponding PV grid connection point.

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

[0077] Optionally, the meaning of the regulation step size in the AVC module is to limit the adjustment range of the reactive power, expressed as ΔQ step = η·Q rated , where η represents the step size ratio, and Q rated represents the rated reactive power capacity of the inverter or reactive power compensation device at the corresponding PV grid connection point.

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

[0079] A PV power generation management control and regulation system of the present invention can issue scheduling instructions for AGC active power dynamic distribution and AVC reactive power collaborative compensation through a system scheduling module, so as to greatly improve the voltage control accuracy and frequency response speed of PV power generation, thereby enhancing the grid stability and the power quality of PV power generation, and further increasing the scene adaptability; the system has strong device access capabilities, supports the access and regulation of a large number of PV power generation devices, and can set the regulation priorities of different PV devices according to actual conditions, so as to meet the device regulation requirements of actual scenarios, and further realizes the dynamic self - adaptation and intelligence of the system.

[0080] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. A photovoltaic power generation management control and regulation system, characterized in that, Including: A data acquisition module, which is set at the grid connection node of the photovoltaic power generation system and is used to collect and transmit various operating data of the grid connection point in real time; A system scheduling module, which, based on the photovoltaic grid connection power adjustment issued by the 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, which dynamically regulates the active power output of the inverter through a priority allocation strategy based on the active power scheduling instruction, and then regulates the grid connection power of the photovoltaic grid connection point; An AVC reactive power regulation module, which coordinately allocates the reactive power output of the reactive power compensation device and the inverter based on the reactive power scheduling instruction, and then regulates the grid connection voltage of the grid connection node of the photovoltaic power generation system; A dynamic response module, which is used to monitor the grid frequency fluctuation of the photovoltaic power generation grid and generate dynamic regulation instructions by using virtual synchronous machine control and fuzzy PID regulation.

2. The photovoltaic power generation management control and adjustment system according to claim 1, wherein, The AGC active power regulation module includes: A first instruction receiving unit, which 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; A first scheduling calculation unit, which is used to receive the data transmitted by the data acquisition module and the data transmitted by the first instruction receiving unit to calculate the regulation target correction value; A first strategy allocation unit, which is used to generate an active power increase regulation strategy instruction or an active power decrease regulation strategy instruction according to the calculation result of the first scheduling calculation unit and transmit it; A first instruction issuing unit, which is used to batch issue the regulation instructions generated by the first strategy allocation unit to the inverters at the grid connection nodes of the photovoltaic power generation system, and monitor the regulation result. If the target value is not reached, a fine-tuning mechanism is triggered.

3. A photovoltaic power generation management control and regulation system according to claim 1, characterized in that, The AVC reactive power regulation module includes: A second instruction receiving unit, which is used to receive the reactive power scheduling instruction issued by the system scheduling module and then parse out the voltage target value or the reactive power target value; A second scheduling calculation unit, which is used to receive the data transmitted by the data acquisition module and the data transmitted by the second instruction receiving unit to generate a reactive power regulation strategy instruction; A second instruction issuing unit, which is used to issue the reactive power regulation strategy instruction generated by the second scheduling calculation unit to the devices at the grid connection nodes of the photovoltaic power generation system step by step.

4. A photovoltaic power generation management control and regulation system according to claim 1, characterized in that, The dynamic response module includes: A virtual synchronous machine control unit, which, based on the data collected by the data acquisition module, simulates the inertia response characteristics of a synchronous generator to stabilize the grid frequency of the photovoltaic power generation grid; A fuzzy PID power smoothing control unit, which is used to suppress the power step change caused by sudden changes in light, and then stabilize the grid power of the photovoltaic power generation grid; A multi-objective coordination logic unit, which is used to coordinate the outputs of the virtual synchronous machine and the fuzzy PID, and issue the dynamic regulation instruction after coordination to avoid control conflicts.

5. A photovoltaic power generation management control and regulation system according to claim 1, characterized in that, It also includes: A reverse power flow prevention module, which is used to predict the reverse power trend of the photovoltaic power generation grid and execute multi-level interlock protection actions. The anti-counterflow module includes: a reverse power calculation unit that calculates the real-time reverse power value and the reverse power value within a 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 thresholds to generate a first-level protection instruction or a second-level protection instruction for transmission; a multi-level interlock protection execution unit that can be used to adjust the output power of the inverter to 90% of the load demand when receiving the first-level protection instruction, thereby achieving rapid adjustment protection; or can be used to disconnect the grid-connected contactor and start the energy storage charging or discharging device when receiving the second-level protection instruction, thereby achieving the protection effect; an alarm and feedback unit that pushes alarm information to the monitoring interface in real time and simultaneously generates an event log to record the trigger event, protection level, and device status.

6. A photovoltaic power generation management control and regulation system according to claim 2, characterized in that, The specific execution steps of the AGC active power regulation module are as follows: 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 checks whether it is within the adjustable range value of the photovoltaic power generation power grid; Step B: Based on the total active power target value, perform target value correction, and then perform regulation with the corrected regulation target value, denoted as P ntarget = P target + ∑P inow - P now , where ∑P inow represents the sum of the real-time powers of all inverters participating in regulation, and n represents the number of grid-connected nodes of the photovoltaic power generation system participating in regulation; Step C, Step C, the first policy allocation unit represents a power difference as P AGC = P ntarget - P now , when P AGC > 0, generate a power increase adjustment policy instruction; when P AGC < 0, generate a power reduction adjustment policy instruction; Step D: The first instruction issuing unit divides the received power increase adjustment strategy instruction or power reduction adjustment strategy instruction by a step size and issues it to the inverters at the grid connection nodes of each photovoltaic power generation system in batches; when it is a power increase adjustment strategy instruction, it is allocated from high to low according to the priority status of the inverters at the grid connection nodes of the photovoltaic power generation system, expressed as When it is a power reduction adjustment strategy instruction, it is allocated from low to high according to the priority status of the inverters at the grid connection nodes of the photovoltaic power generation system, expressed as Step E: The first instruction issuing unit synchronously monitors the regulation result. If the target value is not reached, a fine-tuning mechanism is triggered, expressed as where K adjust represents the regulation coefficient.

7. A photovoltaic power generation management control and regulation system according to claim 3, characterized in that, The specific execution steps of the AVC reactive power regulation module are as follows: 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 and the voltage target value U within the reactive power scheduling instruction; target and the voltage target value U target ; Step B: The second scheduling calculation unit receives the real-time voltage value U of the grid-connected nodes of each photovoltaic power generation system collected by the data acquisition module mea , reactive power value Q mea , the operating status of the SVC / SVG device and the reactive power capacity Q of the grid-connected point inverter gimax ; Step C: The second scheduling calculation unit calculates the reactive power regulation strategy instruction, where the reactive power regulation strategy instruction includes a first reactive power regulation instruction, a second reactive power regulation instruction, and a third reactive power regulation instruction; when Q target ≤λQ svg , it means that only the SVC / SVG device undertakes the regulation, and only the output target voltage of the SVC / SVG device is regulated to generate a first reactive power regulation instruction and transmit it; when λQ svg <Q target ≤λQ svg +∑Q gimax , it means that the reactive power difference of the inverter is preferentially allocated, denoted as ΔQ g =Q target -λQ svg , and the remaining reactive power difference is compensated by the SVC / SVG device to generate a second reactive power regulation instruction and transmit it; when Q target >Q svg +∑Q gimax , it means that the reactive power output value of the inverter is adjusted to Q gimax , and the voltage value of the SVC / SVG device is adjusted according to U target . At this time, the regulation upper limit has been triggered, and a third reactive power regulation instruction and an over-limit alarm warning are transmitted synchronously; where the above λ represents a weight coefficient; Step D: The second instruction issuing unit receives the first reactive power regulation instruction, the second reactive power regulation instruction, or the third reactive power regulation instruction, and issues the corresponding regulation instruction to the corresponding device step by step to complete reactive power regulation.

8. A photovoltaic power generation management control and adjustment system according to claim 2, characterized in that, The meaning of the regulation step length in the AGC module is to limit the adjustment range of the active power, denoted as ΔP step = η·P rated , where η represents the step length ratio and P rated represents the rated active power of the inverter at the corresponding PV power generation grid connection point.

9. A photovoltaic power generation management control and regulation system according to claim 3, characterized in that, The meaning of the regulation step in the AVC module is to limit the adjustment range of reactive power, expressed as ΔQ step = η·Q rated , where η represents the step ratio and Q rated represents the rated reactive power capacity of the inverter or reactive power compensation device at the corresponding grid connection point of photovoltaic power generation.

10. A photovoltaic power generation management control and adjustment system according to claim 5, characterized in that, The constraint conditions of the anti-counterflow module include: a. When the communication of the inverter at the photovoltaic power generation grid connection point is interrupted, the anti-counterflow regulation automatically exits; b. When the inverters at each photovoltaic power generation grid connection point are adjusted to the limit, the AGC regulation function is suspended and an alarm is issued.

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