A collaborative control method for zero-carbon community light storage direct flexible system participating in demand response

Abstract

This invention discloses a collaborative control method for demand response involving photovoltaic (PV), energy storage, direct current (DC), and flexible load systems in zero-carbon communities. It relates to the fields of zero-carbon community energy management, PV-energy storage DC-DC-flexible collaborative control, and demand response technology. The method addresses the problem of local flexible load reduction failing to translate into effective changes in the grid connection point's target direction under PV curtailment conditions, but being mistakenly counted as effective demand response contributions, leading to inflated response capabilities and control deviations. The method acquires the available PV power, actual PV output power, grid connection point power, and flexible load power to determine the PV curtailment power. Under PV curtailment conditions, it determines the correspondence between the decrease in flexible load power and the effective change in the grid connection point's target direction, identifies external ineffective load reduction, and calculates the true response gap accordingly, correcting the control quantities for PV, energy storage, and flexible loads. This method reduces ineffective load reduction on the user side, improves the accuracy of demand response contribution evaluation, and enhances the reliability of collaborative control.

Description

Technical Field

[0001] This application relates to the field of zero-carbon community energy management technology, and in particular to a collaborative control method, apparatus, computer equipment, and computer-readable storage medium for a zero-carbon community photovoltaic-storage-direct-flexible system participating in demand response. Background Technology

[0002] Zero-carbon communities are typically equipped with distributed photovoltaic (PV) systems, energy storage devices, DC power distribution units, and flexible loads such as air conditioning, lighting, DC fresh air systems, water heaters, and charging piles. Through PV power generation, energy storage charging and discharging, and flexible load regulation, zero-carbon communities can adjust the interaction power between the community and the grid according to the demand response instructions issued by the grid side, thereby participating in peak shaving, load regulation, and renewable energy consumption. Existing demand response control methods usually determine the resources that the community can participate in the response based on the current operating power of the flexible loads, the state of charge of the energy storage, and the current output power of the PV systems, and allocate the demand response targets to energy storage devices and various flexible loads.

[0003] However, in a photovoltaic-storage-DC-flexible system, when the photovoltaic power generation capacity is high, the energy storage is close to the charging limit, the grid connection point back-feeding power is limited, or the local load of the community is low, the photovoltaic system may be in a limited power generation state. That is, the photovoltaic modules have a higher power generation capacity, but due to the limitations of local absorption capacity, energy storage charging capacity, or grid connection constraints, the actual output power of the photovoltaic is lower than its power generation capacity. In this state, if the control system continues to reduce local flexible loads, although the load power decreases, the previously unused photovoltaic output may be further restricted, or the photovoltaic power curtailment may increase accordingly, so that the grid connection point power does not change effectively in the target direction according to the load reduction amount.

[0004] Therefore, if existing methods evaluate demand response contribution solely based on the amount of load power reduction or the amount of control commands issued, they may easily mistake local load reduction under photovoltaic curtailment conditions as an effective response contribution to the grid side, leading to an overestimation of the community's effective response capability. Furthermore, the control system may prematurely reduce the adjustment intensity of other controllable resources based on the artificially high response contribution, resulting in insufficient response, ineffective sacrifices on the user side, and distortion of demand response evaluation. Therefore, a collaborative control method for photovoltaic-storage-DC-flexible systems in zero-carbon communities is needed to identify external ineffective reductions that fail to translate into effective changes in grid connection points under photovoltaic curtailment conditions during demand response execution, and to correct the actual response gap and subsequent control quantities accordingly. Summary of the Invention

[0005] This application provides a method, apparatus, computer equipment, and computer-readable storage medium for the coordinated control of a zero-carbon community photovoltaic-storage-flexible system participating in demand response. It can identify whether local flexible load reduction under photovoltaic curtailment conditions has been converted into an effective change in the target direction of the grid connection point, avoiding miscounting local load reductions offset by photovoltaic curtailment as effective demand response contributions. The technical solution is as follows: On the one hand, a collaborative control method for a photovoltaic-storage-direct-connection-flexible system participating in demand response in a zero-carbon community is provided. This method is executed by a zero-carbon community energy management controller. The zero-carbon community includes photovoltaic power generation units, energy storage units, grid connection point metering units, and multiple flexible load control terminals. The method includes: The system receives demand response instructions from the grid side, determines the response execution window, target response power, and target change direction of grid-connected power. Within the response execution window, it acquires the available photovoltaic (PV) power, actual PV output power, grid-connected power, and flexible load power. Based on the available PV power and actual PV output power, it calculates the PV curtailment power. If the PV curtailment power exceeds the curtailment threshold, it determines that the zero-carbon community is in a PV curtailment response state. In the PV curtailment response state, it issues flexible load control instructions to the target flexible loads, determines the decrease in flexible load power based on the flexible load power before and after the issuance of the flexible load control instructions, and determines the effective change in the target direction of the grid-connected power based on the grid-connected power before and after the issuance of the flexible load control instructions. When the power reduction of the flexible load exceeds the reduction judgment threshold, and the effective change in the target direction of the grid connection point is less than the product of the power reduction of the flexible load and the effective response ratio threshold, the external ineffective reduction amount under the photovoltaic curtailment state is determined based on the difference between the power reduction of the flexible load and the effective change in the target direction of the grid connection point; the true response gap is determined based on the target response power and the effective change in the target direction of the grid connection point, and the effective internal response contribution of the target flexible load is corrected based on the external ineffective reduction amount; the corrected collaborative control command is generated based on the true response gap, and the corrected collaborative control command is sent to the photovoltaic power generation unit, energy storage unit and / or flexible load control terminal for execution.

[0006] In one possible implementation, the photovoltaic power limit is the larger value between the photovoltaic power limit minus the actual photovoltaic output power and zero; the photovoltaic power limit can be read from the photovoltaic inverter or photovoltaic monitoring device, or it can be calculated based on the photovoltaic module installed capacity, real-time irradiance, standard irradiance, module temperature, standard temperature and module temperature power coefficient, or it can be determined based on the ratio of the actual photovoltaic output power to the inverter power limit ratio if the inverter power limit ratio is obtained.

[0007] In one possible implementation, the photovoltaic power curtailment response state is further determined by combining the available charging power of the energy storage, the energy storage state of charge, and the grid connection point power constraint value, in order to avoid misjudging normal photovoltaic fluctuations as a power curtailment state.

[0008] In one possible implementation, before determining the effective change in the target direction of the grid connection point, a disturbance correction is made to the effective change in the target direction of the grid connection point based on the change in energy storage charging and discharging power, the change in power of loads not participating in the response, and the change in power of loads with other issued control commands.

[0009] In one possible implementation, when the reduction confirmation windows of multiple target flexible loads overlap, the multiple target flexible loads are identified as a target flexible load group, and the group-level external ineffective reduction amount is calculated.

[0010] On the other hand, a collaborative control device for a zero-carbon community photovoltaic-storage-flexible system to participate in demand response is provided. The device includes an instruction receiving module, a data acquisition module, a limited emission judgment module, a reduction confirmation module, an invalid reduction identification module, a gap calculation module, and a correction control module.

[0011] On the other hand, a computer device is provided, the computer device including a processor and a memory, the memory storing at least one computer program, the computer program being loaded and executed by the processor to implement the operations performed by the above-mentioned collaborative control method for demand response involving zero-carbon community photovoltaic-storage-direct-flexible systems.

[0012] On the other hand, a computer-readable storage medium is provided, wherein at least one computer program is stored in the computer-readable storage medium, the computer program being loaded and executed by a processor to implement the operations performed by the above-mentioned collaborative control method for demand response involving zero-carbon community photovoltaic-storage-flexible systems.

[0013] The solution provided in this application collects not only load power changes, but also photovoltaic (PV) available power, actual PV output power, PV curtailment power, and grid connection point power changes within the demand response execution window. When flexible load power decreases but the grid connection point power does not form a corresponding effective change in the target direction, the invalid part of the corresponding reduction is identified as an external invalid reduction, and this external invalid reduction is deducted from the effective demand response contribution. This avoids miscounting local load reduction as an effective response contribution to the grid side under PV curtailment conditions, improves the accuracy of the actual response gap calculation, and can correct the control quantities of PV, energy storage, and flexible loads based on the actual response gap, reducing ineffective sacrifices on the user side and improving the reliability of zero-carbon communities participating in demand response. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of an implementation environment provided in an embodiment of this application; Figure 2 This is a flowchart of a collaborative control method for a zero-carbon community photovoltaic-storage-flexible system participating in demand response, provided in an embodiment of this application. Figure 3 This is a schematic diagram of an external invalid reduction identification process provided in an embodiment of this application; Figure 4 This is a schematic diagram of a load group confirmation process for multiple target flexible loads provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a collaborative control device provided in an embodiment of this application. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0017] It is understood that the terms “first,” “second,” etc., used in this application may be used to describe various concepts herein, but unless otherwise stated, these concepts are not limited by these terms. These terms are used only to distinguish one concept from another.

[0018] "At least one" refers to one or more, and "multiple" refers to two or more. A window can represent a time interval with start and end times; for example, the pre-instruction sampling window, the reduction confirmation window, and the response execution window can all be time intervals determined by the energy management controller.

[0019] In this embodiment, the effective demand response contribution refers to the effective change in power at the grid connection point along the target change direction within the response execution window; the external ineffective reduction amount refers to the reduction amount corresponding to the photovoltaic curtailment state when the power of the flexible load decreases but does not form an effective change in the target direction at the grid connection point; the effective internal response contribution refers to the remaining part of the power decrease of the flexible load after deducting the external ineffective reduction amount; the flexible load refers to a controllable load that can be collected in real time by the energy management controller and receive power adjustment instructions, including at least one of the following: air conditioning load, lighting load, DC fresh air load, water heater load, and charging pile load.

[0020] It should be noted that the information, data and control signals involved in this application can be obtained or sent by the zero-carbon community energy management controller from the photovoltaic power generation unit, energy storage unit, grid connection point metering unit and flexible load control terminal; the collection, transmission and processing of relevant data can comply with the laws, regulations and standards of relevant countries and regions.

[0021] Figure 1 This is a schematic diagram of an implementation environment provided in an embodiment of this application; see also Figure 1 The implementation environment includes a zero-carbon community energy management controller, a photovoltaic power generation unit, an energy storage unit, a grid connection point metering unit, and multiple flexible load control terminals; the zero-carbon community energy management controller is communicatively connected to the photovoltaic power generation unit, the energy storage unit, the grid connection point metering unit, and the multiple flexible load control terminals.

[0022] A photovoltaic (PV) power generation unit may include PV modules, a PV inverter, and a PV monitoring device. The PV power generation unit is used to report at least one of the following to the energy management controller: actual PV output power, inverter power limiting ratio, estimated maximum power output, and maximum power point tracking status; and to receive PV correction commands from the energy management controller.

[0023] The energy storage unit may include a battery cluster, an energy storage converter, and a battery management system; the energy storage unit is used to report at least one of the following to the energy management controller: energy storage state of charge, real-time energy storage charge and discharge power, maximum allowable energy storage charging power, maximum allowable energy storage discharge power, and upper limit of energy storage state of charge, and to receive energy storage correction commands issued by the energy management controller.

[0024] The grid connection point metering unit may include a smart meter, a grid connection point power acquisition device, or a gate metering device; the grid connection point metering unit is used to report the grid connection point power to the energy management controller according to a preset sampling period; the grid connection point power is positive when electricity is purchased from the grid and negative when electricity is sent to the grid.

[0025] The flexible load control terminal is used to report the real-time power and operating status of the flexible load to the energy management controller, and to receive flexible load control commands. The flexible load control commands may include load identifier, command issuance time, target adjustment power, and target duration.

[0026] Figure 2 This is a flowchart illustrating a collaborative control method for a zero-carbon community photovoltaic-storage-flexible system participating in demand response, provided in an embodiment of this application; see also Figure 2 The method includes the following steps: S201. The energy management controller receives demand response commands from the grid side and determines the response execution window, target response power, and target change direction of power at the grid connection point. Demand response instructions can be issued by the power grid dispatching platform, aggregator platform, or virtual power plant platform; the demand response instructions can include the response start time, response end time, target response power, response type, and grid connection point assessment method; the energy management controller determines the response execution window based on the response start time and response end time, and determines the target change direction of the grid connection point power based on the response type; For example, when the response type is to reduce the purchased power, the target change direction is to reduce the purchased power at the grid connection point; when the response type is to reduce the reverse power or increase the local absorption power, the target change direction is to increase the absorption power at the grid connection point or reduce the reverse power at the grid connection point.

[0027] S202. The energy management controller acquires the photovoltaic power generation capacity, actual photovoltaic output power, grid connection point power, and flexible load power within the response execution window; The actual output power of the photovoltaic system is reported by the photovoltaic inverter or photovoltaic monitoring device; the grid connection point power is reported by the grid connection point metering unit; and the flexible load power is reported by the flexible load control terminal. The sampling period can be 1 second, 5 seconds, 10 seconds or other time intervals, and this application embodiment does not limit this.

[0028] S203, The energy management controller calculates the photovoltaic power-limiting power based on the photovoltaic power generation capacity and the actual photovoltaic output power; Optionally, the photovoltaic power curtailment Pcurt is calculated according to the following formula: Pcurt=max(0,Ppvavail-Ppvout); Where Pcurt represents the photovoltaic curtailment power, in kW; Ppvavail represents the photovoltaic power that can be generated, in kW; Ppvout represents the actual photovoltaic output power, in kW; max(0,·) is used to ensure that the photovoltaic curtailment power is not negative; If sampling data is missing or abnormal, the energy management controller can remove the sampling point or replace it with an adjacent valid sampling point.

[0029] The maximum power output of photovoltaic (PV) power can be obtained in any of the following ways: First, the energy management controller reads the estimated maximum power output from the PV inverter or PV monitoring device; second, the energy management controller calculates it based on the PV module installed capacity, real-time irradiance, standard irradiance, module temperature, standard temperature, and module temperature power factor; third, given the inverter's power limiting ratio, the energy management controller determines it based on the ratio of the actual PV output power to the inverter's power limiting ratio.

[0030] In the second method, the photovoltaic power output Ppvavail can be calculated according to the following formula: Ppvavail=Ppvrated×G / Gstc×[1+α×(T-Tstc)]; Wherein, Ppvrated represents the installed capacity of photovoltaic modules in kW; G represents real-time irradiance in W / m²; Gstc represents standard irradiance in W / m²; α represents the module temperature power coefficient; T represents the module temperature in °C; and Tstc represents the standard temperature in °C.

[0031] In the third method, the photovoltaic power output Ppvavail can be calculated using the following formula: Ppvavail = Ppvout / βlimit; Wherein, βlimit represents the current power limitation ratio of the inverter, and its value is greater than 0 and less than or equal to 1; when βlimit is 0, missing or abnormal, the energy management controller switches to the first mode or the second mode to determine the photovoltaic power that can be generated.

[0032] When multiple methods are available, the energy management controller prioritizes the estimated maximum power output from the photovoltaic inverter or photovoltaic monitoring device; if this value is unavailable, the calculation method based on irradiance and module temperature is used; if irradiance or module temperature is unavailable, but the inverter power limiting ratio is valid, the reverse calculation method based on the inverter power limiting ratio is used.

[0033] S204. The energy management controller determines whether the zero-carbon community is in a state of photovoltaic power curtailment response. In one possible implementation, the energy management controller determines that the zero-carbon community is in a photovoltaic curtailment response state when at least one of the following conditions is met: the photovoltaic curtailment power is greater than the curtailment determination threshold, the available charging power of energy storage is less than the energy storage absorption determination threshold, the energy storage state of charge is greater than or equal to the energy storage charging limit threshold, and the absolute value of the difference between the grid connection point power and the grid connection point power constraint value is less than the grid connection point limit margin.

[0034] Among them, the threshold for determining the power generation limitation can be set to 2% to 10% of the photovoltaic installed capacity, the threshold for determining the energy storage absorption can be set to 5% to 15% of the rated power of the energy storage, and the grid connection point limitation margin can be set according to the metering accuracy of the grid connection point and the grid connection constraint requirements; The aforementioned thresholds can be pre-configured by the energy management controller based on community capacity, equipment rated power, or scheduling rules.

[0035] The available charging power of energy storage, Pesschavail, can be determined based on the maximum allowable charging power of energy storage, Pesschmax, the real-time charging power of energy storage, and the state of charge (SOC) of energy storage. When the SOC is less than the energy storage charging limit threshold, Pesschavail = max(0, Pesschmax - Pesschnow). When the SOC is greater than or equal to the energy storage charging limit threshold, the available charging power of energy storage is determined to be zero, or the available charging power of energy storage is reduced based on the margin between the SOC and the upper limit of the state of charge of energy storage, SOCmax.

[0036] S205. Under the photovoltaic power curtailment response state, the energy management controller issues flexible load control commands to the target flexible load; The flexible load control command includes a load identifier, command issuance time, target reduction power, and target duration. The load identifier is used to indicate the target flexible load, the command issuance time is used to determine the subsequent command pre-sampling window and reduction confirmation window, the target reduction power is used to indicate the expected reduction amount, and the target duration is used to indicate the duration of the reduction action.

[0037] S206, The energy management controller calculates the power reduction of flexible loads; For a target flexible load that receives a flexible load control command, the energy management controller calculates the average power of the target flexible load before the command is issued within the pre-command sampling window before the command is issued, and calculates the average power of the target flexible load after the command is issued within the reduction confirmation window after the command is issued. The difference between the average power before the command and the average power after the command is issued is determined as the power reduction of the flexible load.

[0038] Optionally, the power reduction ΔPL of the flexible load is calculated according to the following formula: ΔPL=max(0,PLbefore-PLafter); Wherein, ΔPL represents the power reduction of the flexible load, in kW; PLbefore represents the average power of the target flexible load before the command, in kW; and PLafter represents the average power of the target flexible load after the command, in kW.

[0039] The sampling window and reduction confirmation window before the instruction can be determined according to the load type; for lighting loads, the reduction confirmation window can be set to 5 to 30 seconds; for DC fresh air loads, the reduction confirmation window can be set to 10 to 60 seconds; for air conditioning loads, the reduction confirmation window can be set to 1 to 5 minutes; for water heater loads, the reduction confirmation window can be set to 1 to 10 minutes; and for charging pile loads, the reduction confirmation window can be set to 10 to 2 minutes.

[0040] S207. The energy management controller calculates the effective change in the target direction of the grid connection point; The energy management controller calculates the average power of the grid-connected point before the instruction within the sampling window before the instruction, and the average power of the grid-connected point after the instruction within the reduction confirmation window; when the target change direction is to reduce the power purchased by the grid-connected point, the effective change amount of the target direction of the grid-connected point is ΔPgrid=max(0,Pgridbefore-Pgridafter); when the target change direction is to increase the power absorbed by the grid-connected point or reduce the power fed back by the grid-connected point, the effective change amount of the target direction of the grid-connected point is ΔPgrid=max(0,Pgridafter-Pgridbefore). Wherein, ΔPgrid represents the effective change in the target direction of the grid connection point, in kW; Pgridbefore represents the average power before the grid connection point command, in kW; and Pgridafter represents the average power after the grid connection point command, in kW.

[0041] In one possible implementation, the energy management controller performs disturbance elimination or disturbance correction before determining the effective change in the target direction at the grid connection point; specifically, the energy management controller acquires the change in energy storage charging and discharging power, the change in power of non-responding loads, and the change in power of other loads for which control commands have been issued within the reduction confirmation window; When the above changes are all less than the corresponding disturbance threshold, the effective change in the target direction of the grid connection point is determined directly based on the average power before the grid connection point command and the average power after the grid connection point command.

[0042] When the change in energy storage charging and discharging power, the change in power of loads not participating in the response, or the change in power of other loads that have been given control commands are greater than or equal to the corresponding disturbance threshold, the energy management controller performs disturbance correction on the effective change in the target direction of the grid connection point; for example, the effective change in the target direction of the grid connection point ΔPgridcorr after disturbance correction can be determined according to the following formula: ΔPgridcorr=max(0, ΔPgrid-ΔPess-ΔPother); Wherein, ΔPess represents the impact of changes in energy storage power on the effective change in the target direction of the grid connection point, and ΔPother represents the impact of loads that did not participate in the response and other loads that have issued control commands on the effective change in the target direction of the grid connection point; in subsequent steps, ΔPgrid can be the disturbance-corrected ΔPgridcorr.

[0043] S208. The energy management controller identifies external ineffective energy reduction processes and calculates the amount of external ineffective energy reduction. The energy management controller calculates the average photovoltaic curtailment power Pcurtafter within the curtailment confirmation window and the average photovoltaic curtailment power Pcurtbefore before the instruction within the instruction sampling window. When Pcurtafter-Pcurtbefore is greater than the curtailment increase judgment threshold, or Pcurtafter is continuously greater than the curtailment maintenance judgment threshold, it indicates that the flexible load reduction may be absorbed by the photovoltaic curtailment power increase or the curtailment maintenance state.

[0044] refer to Figure 3 When the power reduction of the flexible load is greater than the reduction judgment threshold, and the effective change in the target direction of the grid connection point is less than the product of the power reduction of the flexible load and the effective response ratio threshold, the energy management controller determines the external ineffective reduction amount under the photovoltaic curtailment state based on the difference between the power reduction of the flexible load and the effective change in the target direction of the grid connection point.

[0045] Optionally, the external invalidity reduction amount Qinvalid is calculated according to the following formula: Qinvalid=min{ΔPL,max(0,ΔPL-ΔPgrid),Pcurtafter}; Wherein, Qinvalid represents the external ineffective power reduction, in kW; ΔPL represents the power reduction of flexible load, in kW; ΔPgrid represents the effective change in the target direction at the grid connection point, in kW; and Pcurtafter represents the average curtailed power of photovoltaics within the reduction confirmation window, in kW. This formula indicates that the external ineffective power reduction does not exceed the actual power reduction of the target flexible load, does not exceed the portion of the power reduction of the flexible load that does not form an effective change in the target direction at the grid connection point, and does not exceed the photovoltaic curtailed power that still exists within the reduction confirmation window.

[0046] S209. When the confirmation windows for the reduction of multiple target flexible loads overlap, the energy management controller performs load group confirmation; Specifically, the energy management controller identifies multiple target flexible loads as target flexible load groups, calculates the group-level average power before the instruction within the sampling window before the instruction, and the group-level average power after the instruction within the reduction confirmation window. Based on the group-level average power before and after the instruction, the controller determines the group-level flexible load power reduction, and calculates the group-level external ineffective reduction based on the group-level flexible load power reduction, the effective change in the grid connection point target direction, and the average curtailed photovoltaic power within the reduction confirmation window.

[0047] In another possible implementation, the energy management controller staggers the issuance times of commands for multiple target flexible loads, so that the reduction confirmation windows of different target flexible loads do not overlap, thereby identifying the external invalid reduction amount corresponding to each target flexible load one by one.

[0048] S210, the energy management controller calculates the true response gap and corrects the effective internal response contribution of the target flexible load; refer to Figure 4 Optionally, the true response gap G is calculated according to the following formula: G = max(0, Ptarget - ΔPgrid); Where G represents the actual response gap in kW; Ptarget represents the target response power in kW; ΔPgrid represents the effective change in the target direction at the grid connection point in kW; this formula is based on the actual effective change in the target direction at the grid connection point, and external ineffective reductions do not directly offset the actual response gap.

[0049] The effective internal response contribution Qvalidload of the target flexible load can be calculated using the following formula: Qvalidload = max(0, ΔPL - Qinvalid); Wherein, Qvalidload represents the effective internal response contribution of the target flexible load, in kW; Qinvalid represents the external ineffective load reduction, in kW. In this way, the energy management controller can distinguish between the power reduction that has already occurred on the load side and the effective response contribution to the grid connection point, avoiding the subsequent control strategy from prematurely exiting the response based on artificially high internal statistics.

[0050] S211, The energy management controller generates corrected cooperative control commands based on the actual response gap; When the target change direction is to reduce the power purchased at the grid connection point, and releasing the photovoltaic curtailed power will not cause the power at the grid connection point to exceed the grid connection point power constraint value, the energy management controller generates a photovoltaic correction instruction to reduce the photovoltaic curtailment ratio or increase the actual output power of the photovoltaic system; after receiving the photovoltaic correction instruction, the photovoltaic power generation unit adjusts the inverter curtailment ratio or output power.

[0051] When the energy storage state of charge meets the energy storage regulation conditions, the energy management controller generates an energy storage correction command to adjust the energy storage charging and discharging power; the energy storage regulation conditions may include the energy storage state of charge being within the allowable range, the energy storage charging and discharging power not reaching the rated limit, and the energy storage converter being in a controllable state.

[0052] For a target flexible load that is identified as having external ineffective power reduction, the energy management controller stops increasing the power reduction for that target flexible load, or releases the reduced power of that target flexible load according to the recovery slope constraint, in order to reduce ineffective sacrifices on the user side.

[0053] When photovoltaic power generation units and energy storage units cannot cover the actual response gap, the energy management controller selects candidate flexible loads from the flexible loads that have never been identified as having external ineffective reduction, and determines the historical effective response ratio based on the ratio between the effective change of the grid connection point target direction of the candidate flexible load and the power reduction of the flexible load within the historical response window, and allocates the control quantity corresponding to the actual response gap to the candidate flexible load according to the historical effective response ratio.

[0054] Optionally, the historical effective response ratio Rhis is calculated according to the following formula: Rhis = ΣΔPgridhis / ΣΔPLhis; where ΣΔPgridhis represents the sum of effective changes in the target direction of the candidate flexible load within the historical response window, in kW; ΣΔPLhis represents the sum of the power decrease of the candidate flexible load within the historical response window, in kW; when ΣΔPLhis is less than the minimum statistical threshold, the historical effective response ratio of the candidate flexible load is set to the default value, or the candidate flexible load is not included in the candidate set in this round.

[0055] S212, The energy management controller sends the revised coordinated control command to the corresponding photovoltaic power generation unit, energy storage unit and / or flexible load control terminal for execution; After outputting the corrected coordinated control command, the energy management controller can continue to collect the grid-connected power, photovoltaic curtailment power, energy storage charging and discharging power, and flexible load power, and recalculate the true response gap. When the true response gap is less than the gap exit threshold and continues to reach the exit confirmation time, the energy management controller maintains the current control quantity or enters response hold control. When the true response gap is greater than or equal to the gap exit threshold, the coordinated control command correction continues to be executed.

[0056] The collaborative control method provided in this application not only detects whether the power of the flexible load decreases, but also further detects whether the power decrease forms an effective change in the target direction at the grid connection point, and identifies the external ineffective load reduction by combining the change in photovoltaic power curtailment. This can avoid miscounting local load reduction as an effective response contribution to the grid side under photovoltaic power curtailment, improve the accuracy of the calculation of the real response gap, and reduce ineffective load reduction on the user side.

[0057] Figure 5This is a schematic diagram of a collaborative control device provided in an embodiment of this application; the device includes an instruction receiving module, a data acquisition module, a limited-fire judgment module, a reduction confirmation module, an invalid reduction identification module, a gap calculation module, and a correction control module.

[0058] The instruction receiving module is used to receive demand response instructions issued by the grid side, determine the response execution window, target response power, and target change direction of grid-connected power; the data acquisition module is used to acquire photovoltaic power generation capacity, actual photovoltaic output power, grid-connected power, flexible load power, energy storage state of charge, and energy storage charging and discharging power. The power curtailment judgment module is used to calculate the power curtailment of photovoltaics and determine whether the zero-carbon community is in a photovoltaic power curtailment response state; the reduction confirmation module is used to calculate the power reduction of flexible loads and the effective change of the target direction of the grid connection point; the ineffective reduction identification module is used to determine the amount of external ineffective reduction. The gap calculation module is used to calculate the true response gap and correct the effective internal response contribution; the correction control module is used to generate corrected cooperative control instructions based on the true response gap and send the corrected cooperative control instructions to the corresponding execution object.

[0059] Each module in the above device embodiment can be implemented by software, hardware, or a combination of both; it should be noted that the above device and method embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0060] This application embodiment also provides a computer device, which includes a processor and a memory. The memory stores at least one computer program, which is loaded and executed by the processor to implement the operations performed by the above-mentioned collaborative control method for demand response involving a zero-carbon community photovoltaic-storage-direct-flexible system.

[0061] This application also provides a computer-readable storage medium storing at least one computer program, which is loaded and executed by a processor to implement the operations performed by the above-described collaborative control method for demand response involving a zero-carbon community photovoltaic-storage-direct-flexible system.

[0062] The above embodiments are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A collaborative control method for a zero-carbon community photovoltaic-storage-DC-flexible system participating in demand response, characterized in that, The method is executed by a zero-carbon community energy management controller. The zero-carbon community includes photovoltaic power generation units, energy storage units, grid connection point metering units, and multiple flexible load control terminals. The method includes: Receive demand response instructions from the grid side, determine the response execution window, target response power, and target change direction of power at the grid connection point, wherein the target response power is the amount of power change that needs to be formed at the grid connection point along the target change direction; Within the response execution window, the photovoltaic power available for generation, the actual photovoltaic output power, the grid connection point power, and the flexible load power are obtained. The photovoltaic power curtailment power is calculated based on the photovoltaic power available for generation and the actual photovoltaic output power. If the photovoltaic power curtailment power is greater than the curtailment judgment threshold, the zero-carbon community is determined to be in a photovoltaic power curtailment response state. Under the photovoltaic power restriction response state, a flexible load control command is issued to the target flexible load, and the power reduction of the flexible load is determined based on the power of the flexible load before and after the issuance of the flexible load control command. Based on the power of the grid connection point before and after the issuance of the flexible load control command, the effective change in the target direction of the grid connection point is determined. When the power reduction of the flexible load is greater than the reduction judgment threshold, and the effective change in the target direction of the grid connection point is less than the product of the power reduction of the flexible load and the effective response ratio threshold, the external ineffective reduction amount under the photovoltaic power restriction state is determined based on the difference between the power reduction of the flexible load and the effective change in the target direction of the grid connection point. The actual response gap is determined based on the target response power and the effective change in the target direction of the grid connection point, and the effective internal response contribution of the target flexible load is corrected based on the external ineffective reduction amount, wherein the external ineffective reduction amount is not included in the effective demand response contribution. Based on the actual response gap, a corrected collaborative control command is generated and sent to the photovoltaic power generation unit, the energy storage unit, or the flexible load control terminal for execution.

2. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 1, characterized in that, The calculation of photovoltaic power limiting based on the photovoltaic power generation capacity and the actual photovoltaic output power includes: The larger value between the result of subtracting the actual output power of the photovoltaic power from the photovoltaic power that can be generated and zero is determined as the photovoltaic power limit; wherein, the photovoltaic power that can be generated is obtained by any of the following methods: The maximum power output can be estimated from the photovoltaic inverter or photovoltaic monitoring device; or it can be calculated based on the photovoltaic module's installed capacity, real-time irradiance, standard irradiance, module temperature, standard temperature, and module temperature power factor; or, if the inverter's power limiting ratio is obtained, it can be determined based on the ratio of the actual photovoltaic output power to the inverter's power limiting ratio.

3. The collaborative control method for zero-carbon community photovoltaic-storage-DC-flexible system participating in demand response according to claim 1, characterized in that, Before determining that the zero-carbon community is in a state of photovoltaic power curtailment response, the method further includes: Obtain the available charging power of the energy storage, the state of charge of the energy storage, and the power constraint value of the grid connection point; when the photovoltaic power curtailment is greater than the curtailment determination threshold, and at least one of the following is met, determine that the zero-carbon community is in a photovoltaic power curtailment response state: The available charging power of the energy storage is less than the energy storage absorption judgment threshold; the energy storage state of charge is greater than or equal to the energy storage charging limit threshold; the absolute value of the difference between the grid connection point power and the grid connection point power constraint value is less than the grid connection point limit margin.

4. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 3, characterized in that, The available charging power of the energy storage is determined based on the maximum allowable charging power of the energy storage, the real-time charging power of the energy storage, and the state of charge of the energy storage. When the energy storage state of charge is less than the energy storage charging limit threshold, the larger value between the difference between the maximum allowable energy storage charging power and the real-time energy storage charging power and zero is determined as the available energy storage charging power. When the energy storage state of charge is greater than or equal to the energy storage charging limit threshold, the available energy storage charging power is determined to be zero, or the available energy storage charging power is reduced based on the margin between the energy storage state of charge and the upper limit of the energy storage state of charge.

5. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 1, characterized in that, The determination of the decrease in flexible load power based on the flexible load power before and after the issuance of the flexible load control command, and the determination of the effective change in the target direction of the grid connection point based on the grid connection point power before and after the issuance of the flexible load control command, include: Based on the load identifier and instruction issuance time in the flexible load control instruction, determine the target flexible load, the pre-instruction sampling window, and the reduction confirmation window; calculate the average power of the target flexible load before the instruction in the pre-instruction sampling window, and the average power of the target flexible load after the instruction in the reduction confirmation window; The larger value between the result of subtracting the average power after the instruction from the average power before the instruction and zero is determined as the reduction in flexible load power; the grid connection point power is calculated as the average power before the grid connection point instruction within the sampling window before the instruction, and the average power after the grid connection point instruction within the reduction confirmation window. When the target change direction is to reduce the power purchased by the grid connection point, the larger value between the result of subtracting the average power after the grid connection point instruction from the average power before the instruction and zero is determined as the effective change amount of the target direction of the grid connection point; when the target change direction is to increase the power absorbed by the grid connection point or reduce the power fed back to the grid connection point, the larger value between the result of subtracting the average power before the instruction from the average power after the instruction and zero is determined as the effective change amount of the target direction of the grid connection point.

6. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 5, characterized in that, Before determining the effective change in the target direction of the grid connection point, the method further includes: The changes in energy storage charging and discharging power, the changes in power of loads not participating in the response, and the changes in power of other loads that have been issued control commands are obtained within the reduction confirmation window. When the change in energy storage charging and discharging power, the change in power of the non-responding load, and the change in power of other loads that have issued control commands are all less than the corresponding disturbance threshold, the effective change in the target direction of the grid connection point is determined based on the average power before the grid connection point command and the average power after the grid connection point command. When the change in energy storage charging and discharging power, the change in power of non-responding loads, or the change in power of other loads with issued control commands are greater than or equal to the corresponding disturbance threshold, the effective change in the target direction of the grid connection point is disturbed and corrected based on the change in energy storage charging and discharging power, the change in power of non-responding loads, and the change in power of other loads with issued control commands.

7. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 1, characterized in that, The determination of the external ineffective reduction amount under photovoltaic power curtailment includes: The average photovoltaic power curtailment is calculated within the reduction confirmation window, and the average photovoltaic power curtailment before the instruction is issued is calculated within the sampling window before the flexible load control instruction is issued. When the difference between the average photovoltaic power curtailment and the average power curtailment before the photovoltaic instruction is greater than the power curtailment increase judgment threshold, or when the average photovoltaic power curtailment is continuously greater than the power curtailment maintenance judgment threshold, the external ineffective reduction amount is calculated according to the following formula: Qinvalid=min{ΔPL,max(0,ΔPL-ΔPgrid),Pcurtafter}; Wherein, Qinvalid represents the external ineffective reduction amount, ΔPL represents the reduction amount of flexible load power, ΔPgrid represents the effective change amount of the grid connection point target direction, and Pcurtafter represents the average photovoltaic curtailment power within the reduction confirmation window.

8. The collaborative control method for zero-carbon community photovoltaic-storage-DC-flexible system participating in demand response according to claim 1, characterized in that, When the reduction confirmation windows of multiple target flexible loads overlap, the multiple target flexible loads are identified as a target flexible load group; Calculate the average power of the target flexible load group before the instruction within the sampling window before the instruction, and the average power of the target flexible load group after the instruction within the reduction confirmation window; Based on the average power before the group-level instruction and the average power after the group-level instruction, the reduction amount of flexible load power at the group level is determined, and based on the reduction amount of flexible load power at the group level, the effective change amount of the target direction at the grid connection point, and the average curtailed power of photovoltaic power within the reduction confirmation window, the ineffective reduction amount of external power at the group level is calculated.

9. The collaborative control method for zero-carbon community photovoltaic-storage-flexible system participating in demand response according to claim 1, characterized in that, The step of determining the true response gap based on the target response power and the effective change in the target direction of the grid connection point, and correcting the effective internal response contribution of the target flexible load based on the external ineffective reduction amount, includes: The larger value between the target response power minus the effective change in the target direction of the grid connection point and zero is determined as the true response gap; the remaining part of the decrease in flexible load power after deducting the external ineffective reduction is determined as the effective internal response contribution of the target flexible load. The effective demand response contribution is the effective change in the grid-connected power along the target change direction within the response execution window.

10. The collaborative control method for zero-carbon community photovoltaic-storage-DC-flexible system participating in demand response according to claim 1, characterized in that, The step of generating the corrected cooperative control command based on the actual response gap includes at least one of the following: When the target change direction is to reduce the power purchased at the grid connection point, and releasing the photovoltaic curtailed power will not cause the power at the grid connection point to exceed the grid connection point power constraint value, a photovoltaic correction instruction is generated to reduce the photovoltaic curtailment ratio or increase the actual output power of the photovoltaic. When the energy storage state of charge meets the energy storage regulation conditions, an energy storage correction command is generated to adjust the energy storage charging and discharging power. Stop increasing the reduction amount to the target flexible load that has been determined to have external invalid reduction amount, or release the reduced power of the target flexible load according to the recovery slope constraint; Candidate flexible loads are selected from flexible loads that have never been identified as having external ineffective reduction. The historical effective response ratio is determined based on the ratio between the effective change in the grid connection point target direction of the candidate flexible load within the historical response window and the power reduction of the flexible load. The control quantity corresponding to the actual response gap is allocated to the candidate flexible load according to the historical effective response ratio.

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