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CN-122026524-A - Photovoltaic waste photoelectric quantity analysis method and device based on household polling and instantaneous sampling

CN122026524ACN 122026524 ACN122026524 ACN 122026524ACN-122026524-A

Abstract

The invention discloses a photovoltaic waste photoelectric quantity analysis method and device based on household polling and instantaneous sampling, and relates to the technical field of distributed energy management and power grid regulation. The method comprises the steps of firstly controlling a photovoltaic cluster to respond to a power grid instruction, maintaining a steady state regulation state with constant total output power, then controlling a first part of photovoltaic units to normally release output according to a preset sequence on the premise of keeping the total power stable, controlling a second part of photovoltaic units to temporarily compensate and offset disturbance, maintaining the total power stable, then conducting instantaneous sampling, constructing a theoretical power generation capacity curve by adopting a linear interpolation method based on adjacent twice sampling data, obtaining time-period waste electric quantity through integral operation, and finally accumulating the total waste electric quantity of a single unit and summarizing the total waste electric quantity of the cluster. The invention realizes the coordination of power grid regulation and control and power-discarding metering, has high metering precision and small influence on the power grid, can support economic compensation and dispatching optimization, and is suitable for various photovoltaic cluster scenes.

Inventors

  • YU LIN
  • LI BINGZHI
  • ZHOU ZHENG
  • XIAO ZHIQIANG
  • LI WEIHUI
  • Zhang Daidai

Assignees

  • 用尚能源互联网智能研究院(天津)有限公司
  • 北京用尚科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260410

Claims (10)

  1. 1. The photovoltaic waste photoelectric quantity analysis method based on household polling and instantaneous sampling is characterized by comprising the following steps of: 1) Controlling a photovoltaic cluster to respond to a power grid dispatching instruction, and enabling the photovoltaic cluster to enter and continuously maintain a steady-state regulation and control state with constant total output power through initial power distribution and dynamic fine adjustment; 2) Controlling the first part of photovoltaic units to normally release output according to a preset sequence, simultaneously controlling the second part of photovoltaic units to temporarily compensate and offset the disturbance to maintain the total power stable, and then performing instantaneous sampling; 3) Based on sampling data of the same photovoltaic unit, constructing a theoretical power generation capacity curve of the photovoltaic unit in a sampling period by adopting a linear interpolation method, and solving a difference value between a theoretical maximum power generation capacity and an actual power generation capacity through integral operation to obtain a light-discarding electric quantity in the sampling period; 4) And accumulating the photovoltaic power discarding quantity of a single photovoltaic unit in a designated period in the whole regulation period, and summarizing the total photovoltaic power discarding quantity of all the photovoltaic units to finally obtain the total photovoltaic power discarding quantity generated by the photovoltaic cluster in response to the power grid regulation command.
  2. 2. The method for analyzing photovoltaic waste photoelectric quantity based on household polling and instantaneous sampling according to claim 1, wherein the step 1) specifically comprises the following steps: 11 Receiving a regulation command from a power grid dispatching system, and extracting a regulation power target value contained in the regulation command; 12 Acquiring the available power generation capacity of the appointed photovoltaic units in the cluster through a prediction algorithm or real-time data acquisition, calculating an initial power set value of each photovoltaic unit according to the available power generation capacity, and transmitting the initial power set value to a control terminal of the appointed photovoltaic units; 13 The total output power of the photovoltaic clusters is collected in real time through the power monitoring assembly, the output force of the photovoltaic units is dynamically and finely adjusted and set by adopting a PID control method, the total power of the clusters is converged to a regulated power target value and is stably maintained, and the steady-state regulation state establishment is completed.
  3. 3. The method for analyzing photovoltaic waste photoelectric quantity based on household polling and instantaneous sampling according to claim 1, wherein the step 2) specifically comprises the following steps: 21 Maintaining a polling queue containing unique identifiers of all N photovoltaic units in the cluster, and sequentially selecting a next 'current metering unit' to be sampled from the queue by the controller; 22 Transmitting a power limit release instruction to a control terminal of the current metering unit to enable the current metering unit to release power constraint in a very short time, and outputting theoretical maximum power under the current working condition by the inverter at a maximum response speed; 23 At the same time of sending the limitation removing instruction, sending a temporary additional down-regulating instruction to the rest N-1 photovoltaic units in the cluster, and requiring the rest N-1 photovoltaic units to instantaneously and additionally reduce power predicted values on the basis of the current output, wherein the sum of the power predicted values of all the photovoltaic units is approximately equal to the expected increased power after the limitation is removed by the current metering unit, and the expected increased power is estimated by historical operation data of the current metering unit or a short-term power generation predicted result; 24 After the theoretical maximum power sampling of the current metering unit is finished, immediately sending a power recovery instruction to the current metering unit to enable the power recovery instruction to return to the steady-state regulation and control state, and simultaneously sending a temporary time regulation instruction release notice to the rest N-1 photovoltaic units to enable the total power of the whole photovoltaic cluster to be maintained constant again; 25 The pointer of the polling queue is moved backwards by one bit, the step 21) is returned to be repeatedly executed, and the cyclic periodic sampling of all photovoltaic units in the cluster is realized.
  4. 4. The method for analyzing photovoltaic waste photoelectric quantity based on household polling and instantaneous sampling according to claim 1, wherein the step 3) specifically comprises the following steps: 31 For any photovoltaic unit, the time when the photovoltaic unit is sampled last twice is respectively recorded as And The corresponding two theoretical power sampling values are respectively recorded as And ; 32 Supposedly in a time interval In the inside, the theoretical maximum power generation capacity of the photovoltaic unit From the slave Change linearly to For any time τ in the interval, the theoretical power satisfies the formula: ; In the formula, As the theoretical maximum power at time tau, For the time interval of two samples, The time difference between the time tau and the j-th sampling time; Is that Theoretical maximum power at time; Is that Theoretical maximum power at time; 33 During a time interval) In, discard the photoelectric quantity For the difference value between the theoretical maximum power generation amount and the actual power generation amount in the period, the power difference is obtained through integral operation, and the formula is satisfied: ; In the formula, Is a time interval The electric quantity of the abandoned light in the interior, For the actual output power of the unit in the regulation state, the upper and lower limits are integrated And The start time and the end time of the period, respectively.
  5. 5. The method for analyzing photovoltaic waste photoelectric quantity based on household polling and instantaneous sampling according to claim 1, wherein the step 4) specifically comprises the following steps: 41 For each photovoltaic unit, collecting all the light-discarding electric quantity in the sampling period calculated in the step 3) in the whole regulation period, and carrying out accumulation operation on the light-discarding electric quantity in all the sampling period to obtain the total light-discarding electric quantity of the photovoltaic unit in the current regulation period; 42 Statistics of total power rejection of all N photovoltaic units within a photovoltaic cluster For all N photovoltaic units Performing summation operation to finally obtain total waste photovoltaic power generated by the whole photovoltaic cluster in response to the current power grid regulation command The method comprises the following steps: ; In the formula, Is the total power rejection of the ith photovoltaic unit.
  6. 6. Photovoltaic light-discarding electric quantity analysis device based on household polling and instantaneous sampling is characterized by comprising: The power grid dispatching instruction response module is used for controlling the photovoltaic cluster to respond to a power grid dispatching instruction, and enabling the photovoltaic cluster to enter and continuously maintain a steady-state regulation and control state with constant total output power through initial power distribution and dynamic fine adjustment; The second-level instantaneous power sampling module is used for controlling the first part of photovoltaic units to normally release output according to a preset sequence, controlling the second part of photovoltaic units to temporarily compensate and offset disturbance to maintain stable total power, and then performing instantaneous sampling; The photovoltaic unit comprises a photovoltaic unit, a photovoltaic power generation amount analysis module, a linear interpolation method, a power generation amount calculation module and a power generation amount calculation module, wherein the photovoltaic power generation amount analysis module is used for constructing a theoretical power generation amount curve of the photovoltaic unit in a sampling period based on sampling data of two adjacent photovoltaic units, and solving a difference value between a theoretical maximum power generation amount and an actual power generation amount through integral operation to obtain a photovoltaic power generation amount in the sampling period; And the total waste photoelectric quantity analysis module is used for accumulating the waste photoelectric quantity of a single photovoltaic unit in a designated period in the whole regulation period, summarizing the total waste electric quantity of all the photovoltaic units and finally obtaining the total waste photoelectric quantity generated by the photovoltaic cluster in response to the power grid regulation command.
  7. 7. The split polling and instantaneous sampling based photovoltaic reject amount analysis device of claim 6, wherein the grid scheduling instruction response module comprises: The regulation and control instruction analysis sub-module is used for receiving a regulation and control instruction from the power grid dispatching system and extracting a regulation and control power target value contained in the regulation and control instruction; The initial power distribution sub-module is used for acquiring the available power generation capacity of the appointed photovoltaic units in the cluster through a prediction algorithm or real-time data acquisition, calculating an initial power set value of each photovoltaic unit according to the available power generation capacity, and transmitting the initial power set value to a control terminal of the appointed photovoltaic units; and the power dynamic fine adjustment sub-module is used for collecting the total output power of the photovoltaic cluster in real time through the power monitoring assembly, dynamically fine-adjusting and setting the output force of the photovoltaic unit by adopting a PID control method, converging the total power of the cluster to a regulated power target value and stably maintaining the regulated power target value, and completing the establishment of a steady state regulation state.
  8. 8. The split polling and instantaneous sampling based photovoltaic reject photo-electric quantity analysis device according to claim 6, wherein the second-level instantaneous power sampling module comprises: The sampling unit selecting submodule is used for maintaining a polling queue containing unique identifiers of all N photovoltaic units in the cluster, and the controller sequentially selects a next current metering unit to be sampled from the queue; The sampling unit de-limit submodule is used for sending a power limit removing instruction to a control terminal of the current metering unit so that the current metering unit removes power constraint in a very short time, and the inverter outputs theoretical maximum power under the current working condition at the maximum response speed; The residual unit compensation sub-module is used for sending a temporary additional down-regulation instruction to the residual N-1 photovoltaic units in the cluster at the same moment of sending the limit removing instruction, and requiring the residual N-1 photovoltaic units to instantaneously and additionally reduce power predicted values on the basis of the current output, wherein the sum of the power predicted values of all the photovoltaic units is approximately equal to the expected increased power after the limit removing of the current metering unit, and the expected increased power is estimated by historical operation data of the current metering unit or a short-term power generation predicted result; The power state recovery sub-module is used for immediately sending a power recovery instruction to the current metering unit after finishing the theoretical maximum power sampling of the current metering unit so as to enable the current metering unit to return to the steady state regulation and control state, and simultaneously sending a temporary down regulation instruction release notice to the rest N-1 photovoltaic units so as to enable the total power of the whole photovoltaic cluster to be maintained constant again; And the cyclic polling execution sub-module is used for moving the pointer of the polling queue backwards by one bit so as to realize cyclic periodic sampling of all photovoltaic units in the cluster.
  9. 9. The split polling and instantaneous sampling based photovoltaic reject photo-voltaic analysis device of claim 6, wherein the sample period reject photo-voltaic analysis module comprises: the sampling data extraction sub-module is used for extracting the time of the last twice sampling of any photovoltaic unit as respectively recorded as And The corresponding two theoretical power sampling values are respectively recorded as And ; A theoretical power interpolation sub-module for assuming that the time interval is In the inside, the theoretical maximum power generation capacity of the photovoltaic unit From the slave Change linearly to For any time τ in the interval, the theoretical power satisfies the formula: ; In the formula, As the theoretical maximum power at time tau, For the time interval of two samples, The time difference between the time tau and the j-th sampling time; Is that Theoretical maximum power at time; Is that Theoretical maximum power at time; a power-curtailed integral calculation sub-module for calculating the power-curtailed integral of the power In, discard the photoelectric quantity For the difference value between the theoretical maximum power generation amount and the actual power generation amount in the period, the power difference is obtained through integral operation, and the formula is satisfied: ; In the formula, Is a time interval The electric quantity of the abandoned light in the interior, For the actual output power of the unit in the regulation state, the upper and lower limits are integrated And The start time and the end time of the period, respectively.
  10. 10. The split polling and instantaneous sampling based photovoltaic reject amount analysis device of claim 6, wherein the total reject amount analysis module comprises: The unit waste electricity accumulation sub-module is used for collecting the waste electricity in all the sampling periods calculated in the step 3) in the whole regulation period for each photovoltaic unit, and carrying out accumulation operation on the waste electricity in all the sampling periods to obtain the total waste electricity of the photovoltaic unit in the current regulation period; the cluster waste electric quantity summarizing sub-module is used for counting total waste electric quantity of all N photovoltaic units in the photovoltaic cluster For all N photovoltaic units Performing summation operation to finally obtain total waste photovoltaic power generated by the whole photovoltaic cluster in response to the current power grid regulation command The method comprises the following steps: ; In the formula, Is the total power rejection of the ith photovoltaic unit.

Description

Photovoltaic waste photoelectric quantity analysis method and device based on household polling and instantaneous sampling Technical Field The invention belongs to the technical field of distributed energy management and power grid regulation and control, and particularly relates to a photovoltaic waste photoelectric quantity analysis method and device based on household polling and instantaneous sampling. Background With the acceleration of global energy transformation process, the distributed photovoltaic power generation continuously climbs in an electric power system by virtue of the advantages of clean low carbon, flexible deployment and the like. However, the photovoltaic output has obvious intermittence and fluctuation under the influence of natural conditions such as illumination intensity, ambient temperature and the like, and the access of large-scale distributed photovoltaic brings challenges to the safe and stable operation of a power grid. In order to balance power supply and demand and ensure stable power grid frequency and voltage, a power grid dispatching system needs to send down-regulating power (namely, light discarding) regulating and controlling instructions to a photovoltaic cluster, and a photovoltaic unit is required to reduce actual output power, which inevitably leads to waste of part of theoretical power generation capacity. In practical application, the method for estimating the abandoned photovoltaic energy has the technical bottleneck that on one hand, the theoretical maximum power generation capacity of the photovoltaic unit dynamically and severely fluctuates along with environmental conditions, the theoretical power generation capacity of the photovoltaic unit cannot be directly measured in real time under the power limiting state of executing a power grid regulation instruction, and on the other hand, the traditional method for estimating the abandoned photovoltaic energy is mostly dependent on historical data fitting or numerical simulation, individual differences and real-time working condition changes of single photovoltaic units are not fully considered, so that an estimation result error is larger and the method is difficult to be used as a reliable basis for economic compensation and scheduling optimization. In the prior art, partial schemes attempt to estimate the power rejection amount by adding monitoring equipment or an optimization algorithm, but the method has the defects that a large amount of high-precision sensing equipment is required to be additionally deployed, so that the cost is greatly increased and the compatibility is poor, on the one hand, the total power of the photovoltaic cluster cannot be maintained stable in the metering process, the power fluctuation of a power grid is easily caused, the continuous execution of a power grid regulation instruction is influenced, and in addition, the metering process lacks fairness and transparency, so that the power rejection responsibility and the actual loss of different photovoltaic units cannot be accurately distinguished. Disclosure of Invention Therefore, the invention provides a photovoltaic waste photoelectric quantity analysis method and device based on household polling and instantaneous sampling, which solve the problems that when a distributed photovoltaic cluster executes a power grid waste light instruction, the power generation capacity of a photovoltaic theory dynamically fluctuates and cannot be directly measured in a regulation and control state, so that the waste photoelectric quantity has a large estimation error afterwards. In order to achieve the purpose, the invention provides the following technical scheme that the photovoltaic waste photoelectric quantity analysis method based on individual polling and instantaneous sampling comprises the following steps: 1) Controlling a photovoltaic cluster to respond to a power grid dispatching instruction, and enabling the photovoltaic cluster to enter and continuously maintain a steady-state regulation and control state with constant total output power through initial power distribution and dynamic fine adjustment; 2) Controlling the first part of photovoltaic units to normally release output according to a preset sequence, simultaneously controlling the second part of photovoltaic units to temporarily compensate and offset the disturbance to maintain the total power stable, and then performing instantaneous sampling; 3) Based on sampling data of the same photovoltaic unit, constructing a theoretical power generation capacity curve of the photovoltaic unit in a sampling period by adopting a linear interpolation method, and solving a difference value between a theoretical maximum power generation capacity and an actual power generation capacity through integral operation to obtain a light-discarding electric quantity in the sampling period; 4) And accumulating the photovoltaic power discarding quantity of a single photovoltaic unit in a designated pe