WO2022267409A1 - 光伏发电系统控制方法、装置、功率优化器及存储介质 - Google Patents

光伏发电系统控制方法、装置、功率优化器及存储介质 Download PDF

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WO2022267409A1
WO2022267409A1 PCT/CN2021/141371 CN2021141371W WO2022267409A1 WO 2022267409 A1 WO2022267409 A1 WO 2022267409A1 CN 2021141371 W CN2021141371 W CN 2021141371W WO 2022267409 A1 WO2022267409 A1 WO 2022267409A1
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Prior art keywords
power
voltage
segment
output
curve
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PCT/CN2021/141371
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English (en)
French (fr)
Inventor
卫建荣
范杨平
付勇
吕剑
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西安领充创享新能源科技有限公司
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Priority to EP21946882.4A priority Critical patent/EP4231480A1/en
Publication of WO2022267409A1 publication Critical patent/WO2022267409A1/zh

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/381—Dispersed generators
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
    • G05F1/66—Regulating electric power
    • G05F1/67—Regulating electric power to the maximum power available from a generator, e.g. from solar cell
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F3/00—Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties
    • G05F3/02—Regulating voltage or current
    • G05F3/08—Regulating voltage or current wherein the variable is dc
    • G05F3/10—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics
    • G05F3/16—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices
    • G05F3/20—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices using diode- transistor combinations
    • G05F3/24—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices using diode- transistor combinations wherein the transistors are of the field-effect type only
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20—The dispersed energy generation being of renewable origin
    • H02J2300/22—The renewable source being solar energy
    • H02J2300/24—The renewable source being solar energy of photovoltaic origin
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20—The dispersed energy generation being of renewable origin
    • H02J2300/22—The renewable source being solar energy
    • H02J2300/24—The renewable source being solar energy of photovoltaic origin
    • H02J2300/26—The renewable source being solar energy of photovoltaic origin involving maximum power point tracking control for photovoltaic sources
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/56—Power conversion systems, e.g. maximum power point trackers

Definitions

  • the present application relates to the technical field of power electronics, in particular, to a photovoltaic power generation system control method, device, power optimizer and storage medium.
  • Photovoltaic power generation is a technology that directly converts light energy into electrical energy by using the photovoltaic effect at the semiconductor interface. It is mainly composed of photovoltaic panels (components), controllers and inverters, and the main components are composed of electronic components. The solar cells are packaged and protected after being connected in series to form a large-area solar cell module, and then cooperate with power controllers and other components to form a photovoltaic power generation device.
  • photovoltaic power generation systems there are centralized and distributed systems.
  • the photovoltaic panels are generally connected in series to form a high-voltage input to the photovoltaic inverter, and the photovoltaic inverter performs the function of Maximum Power Point Tracking (MPPT for short);
  • MPPT Maximum Power Point Tracking
  • the photovoltaic inverter consists of two stages, the first stage DC/DC completes the boost and MPPT functions, and the latter stage completes the stable input voltage and inverter functions.
  • the photovoltaic panel is equipped with a power optimizer
  • the rear stage of the power optimizer is connected to the photovoltaic inverter, and the power optimizer performs functions such as boosting, isolation, and MPPT
  • the photovoltaic inverter completes the functions of stabilizing the input voltage and inverting.
  • the present application provides a photovoltaic power generation system control method, device, power optimizer and storage medium, so as to balance the competitive relationship between the power optimizer and photovoltaic inverter, and avoid the situation of mismatch oscillation, thereby at least overcoming the above The mentioned deficiencies in the related art.
  • Some embodiments of the present application provide a photovoltaic power generation system control method, which is applied to a power optimizer in a photovoltaic power generation system.
  • the photovoltaic power generation system control method may include:
  • the output power is obtained; wherein, the first mapping curve is used to indicate the corresponding relationship between the output voltage and the output power of the power optimizer, and the first mapping
  • the curves include: a first voltage segment linear power curve and a second voltage segment linear power curve, wherein the voltage corresponding to the second voltage segment is higher than the voltage corresponding to the first voltage segment;
  • the first mapping curve may further include: a constant power section of a third voltage section, wherein the voltage corresponding to the third voltage section may be higher than the voltage corresponding to the first voltage section and lower than the voltage corresponding to the first voltage section.
  • the voltage corresponding to the second voltage segment may further include: a constant power section of a third voltage section, wherein the voltage corresponding to the third voltage section may be higher than the voltage corresponding to the first voltage section and lower than the voltage corresponding to the first voltage section.
  • the linear power curve in the first voltage segment may be a linear curve in which power increases as the voltage increases or power decreases as the voltage decreases
  • the linear power curve in the second voltage segment may indicate that the power decreases or the power decreases as the voltage increases.
  • the obtaining the output power according to the actual input power and the pre-generated first mapping curve may include:
  • the bus voltage after the disturbance of the post-stage photovoltaic inverter is in the first voltage segment or the second voltage segment, it can be obtained according to the linear power curve of the first voltage segment or the linear power curve of the second voltage segment Output Power.
  • the obtaining the output power according to the actual input power and the pre-generated first mapping curve may further include:
  • the output power can be obtained according to the constant power segment of the third voltage segment.
  • said obtaining the output power according to the third voltage segment constant power segment may include:
  • the actual input power may be used as the output power.
  • said obtaining the output power according to the third voltage segment constant power segment may also include:
  • the maximum limited power may be used as the output power.
  • the output power may further include:
  • the corresponding relationship between the first voltage segment, the second voltage segment and the output power is respectively adjusted to obtain the first mapping curve.
  • adjusting the corresponding relationship between the first voltage segment, the second voltage segment and the output power may include:
  • the corresponding relationship between the second voltage segment and the output power is adjusted to a linear relationship in which the power decreases as the voltage increases.
  • the method may further include:
  • the maximum power point and the given voltage corresponding to the maximum power point determine the first given current; wherein the maximum power point is the maximum power point unit in the power optimizer, according to the input voltage and input current Obtained by disturbance;
  • the duty cycle of the power optimizer is adjusted.
  • control device for a photovoltaic power generation system may include: an acquisition module, a processing module, and a determination module;
  • the obtaining module can be configured to obtain the input current and input voltage of the power optimizer
  • the processing module may be configured to obtain actual input power according to the input voltage and the input current; obtain output power according to the actual input power and a pre-generated first mapping curve; wherein, the first A mapping curve is used to indicate the corresponding relationship between the output voltage and output power of the power optimizer, and the first mapping curve may include: a linear power curve in a first voltage segment and a linear power curve in a second voltage segment, wherein the The voltage corresponding to the second voltage segment may be higher than the voltage corresponding to the first voltage segment;
  • the determining module may be configured to output the bus voltage corresponding to the output power to the subsequent photovoltaic inverter, so that the latter photovoltaic inverter determines the target maximum power according to the bus voltage.
  • the first mapping curve may further include: a third voltage segment constant power segment, wherein the voltage corresponding to the third voltage segment may be higher than the voltage corresponding to the first voltage segment, and may be lower than a voltage corresponding to the second voltage segment;
  • the linear power curve in the first voltage segment may be a linear curve in which power increases as the voltage increases or power decreases as the voltage decreases
  • the linear power curve in the second voltage segment may indicate that the power decreases or the power decreases as the voltage increases.
  • processing module may also be configured to:
  • the output power If it is detected that the bus voltage after the disturbance of the post-stage photovoltaic inverter is in the first voltage segment or the second voltage segment, then according to the linear power curve of the first voltage segment or the linear power curve of the second voltage segment, the output power.
  • processing module may also be configured to:
  • the output power is obtained according to the constant power segment of the third voltage segment.
  • processing module may also be configured to:
  • the actual input power is less than or equal to the maximum limited power of the power optimizer, the actual input power is used as the output power.
  • processing module may also be configured to:
  • the maximum limited power is used as the output power.
  • the device may further include: an adjustment module;
  • the adjustment module may be configured to adjust the corresponding relationship between the first voltage segment, the second voltage segment and the output power respectively, so as to obtain the first mapping curve.
  • the adjustment module can also be configured to:
  • the corresponding relationship between the second voltage segment and the output power is adjusted to a linear relationship in which the power decreases as the voltage increases.
  • processing module may also be configured to:
  • the maximum power point and the given voltage corresponding to the maximum power point determine the first given current; wherein the maximum power point is the maximum power point unit in the power optimizer, according to the input voltage and input current obtained by performing disturbance; determining a second given current according to the output power and the output voltage corresponding to the output power; obtaining a minimum given current according to the first given current and the second given current;
  • the apparatus may further include: an adjustment module configured to adjust a duty cycle of the power optimizer using the minimum given current.
  • Some other embodiments of the present application also provide a power optimizer, which may include: a processor, a storage medium, and a bus.
  • the storage medium stores machine-readable instructions executable by the processor.
  • the power optimizer runs When, the processor communicates with the storage medium through a bus, and the processor executes the machine-readable instructions, so as to execute the steps of the photovoltaic power generation system control method provided in the above-mentioned embodiments.
  • Still other embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored, and when the computer program is run by a processor, the photovoltaic power generation system control provided by the above-mentioned embodiments is executed. method steps.
  • the embodiment of the present application provides a photovoltaic power generation system control method, device, power optimizer and storage medium, the method includes: obtaining the input current and input voltage of the power optimizer; obtaining the actual input power according to the input voltage and input current; The actual input power and the pre-generated first mapping curve are used to obtain the output power; wherein, the first mapping curve is used to indicate the corresponding relationship between the output voltage and the output power of the power optimizer, and the first mapping curve includes: the linear power of the first voltage segment curve and the linear power curve of the second voltage segment, wherein the voltage corresponding to the second voltage segment is higher than the voltage corresponding to the first voltage segment; the bus voltage corresponding to the output power is output to the subsequent photovoltaic inverter, so that the subsequent photovoltaic The inverter determines the target maximum power according to the bus voltage.
  • the external characteristics of the power-voltage relationship curve of the high-voltage and low-voltage sections of the power optimizer are adjusted, so that when the first MPPT unit is disturbed at the point near Vo1 (or Vo4), it can be based on the actual input power, pre-determined Generate the first mapping curve to obtain the output power, and output the bus voltage corresponding to the output power to the subsequent photovoltaic inverter, so that the latter photovoltaic inverter can disturb the bus voltage to obtain the target maximum power of the photovoltaic power generation system , effectively solve the phenomenon that the output power Po of the power optimizer jumps from constant power to 0 when the first MPPT unit in the power optimizer is disturbed at a point near Vo1 (or Vo4), so that the power optimizer can automatically adapt to the subsequent stage
  • the disturbance voltage change of the connected "photovoltaic inverter" effectively balances the competitive relationship between the "power optimizer" and "photovoltaic inverter", and avoids the situation of mismatch oscillation.
  • FIG. 1 is a schematic structural diagram of a photovoltaic power generation system provided in an embodiment of the present application
  • FIG. 2 is a schematic structural diagram of a power optimizer provided in an embodiment of the present application
  • Fig. 3 is a schematic flowchart of a method for controlling a photovoltaic power generation system provided in an embodiment of the present application
  • FIG. 4 is a schematic diagram of the external characteristic curve of the output voltage and output power of the power optimizer in the related art
  • FIG. 5 is a schematic diagram of an external characteristic curve of output voltage and output power of a power optimizer provided by an embodiment of the present application
  • Fig. 6 is a schematic flowchart of another method for controlling a photovoltaic power generation system provided in the embodiment of the present application.
  • FIG. 7 is a schematic diagram of the working principle of the MPPT unit and the output voltage limiting power loop in the power optimizer in a photovoltaic power generation system control method provided by the embodiment of the present application;
  • Fig. 8 is a schematic diagram of the overall flow of a photovoltaic power generation system control method provided by the embodiment of the present application.
  • Fig. 9 is a schematic structural diagram of a control device for a photovoltaic power generation system provided by an embodiment of the present application.
  • Icons 100-photovoltaic power generation system; 101-power optimizer; 102-photovoltaic inverter.
  • the working principle of the MPPT unit detect the voltage and current generated by the photovoltaic panel in real time, and determine the disturbance direction of the next cycle by measuring the output power and voltage of the photovoltaic panel before and after the disturbance.
  • the disturbance direction is correct, the photovoltaic cell As the output power of the panel increases, it will continue to disturb in the same direction in the next cycle; otherwise, it will disturb in the opposite direction. In this way, the disturbance and observation are repeated to realize the tracking of the maximum power point of the photovoltaic panel.
  • the "power optimizer” and “photovoltaic inverter” are designed and manufactured by different manufacturers, and only the “power optimizer” or “photovoltaic inverter” in the photovoltaic power generation system is considered according to the power in the photovoltaic power generation system.
  • the voltage characteristic curve performs maximum power point tracking, so that the photovoltaic power generation system can work at the maximum power point to make full use of solar energy resources, and achieve the purpose of improving the energy conversion efficiency of the photovoltaic power generation system.
  • the inventive idea of the application scheme is to adjust the power-voltage relationship curve of the high and low voltage section of the power optimizer, so that the "power optimizer" in the photovoltaic power generation system can automatically adapt to the maximum power point when seeking the maximum power point.
  • the power change of the "photovoltaic inverter” connected in stages thus effectively balancing the competitive relationship between the "power optimizer” and “photovoltaic inverter", avoiding the situation of mismatch oscillation.
  • Fig. 1 is a schematic structural diagram of a photovoltaic power generation system provided by the embodiment of the present application; , at least one power optimizer 101 , and a photovoltaic inverter 102 .
  • the embodiment of the present application provides a distributed photovoltaic power generation system.
  • the power optimizer 101 can adopt a multi-channel isolated boosting scheme, and multiple channels can independently run MPPT to track the maximum power of each photovoltaic panel and the conversion efficiency. High, the outputs are connected in parallel.
  • the photovoltaic panels can be connected to the power optimizer 101, and the photovoltaic panels input the generated voltage and current to the power optimizer, and each power The optimizer 101 uses the input to run MPPT independently, so that the power optimizer 101 can detect the power generation voltage of the photovoltaic panel in real time, and obtain the actual output power of the power optimizer 101 according to the photovoltaic power generation system control method provided in this application.
  • Each power optimizer connects their output voltages in parallel to form a DC bus voltage (DC+, DC-), and the photovoltaic inverter 102 obtains the target maximum power of the photovoltaic power generation system 100 according to the DC bus voltage.
  • the photovoltaic inverter 102 will The DC voltage corresponding to the target maximum power is converted to AC voltage and output to the grid.
  • FIG. 2 is a schematic structural diagram of a power optimizer provided by an embodiment of the present application; as shown in FIG. 2 , the power optimizer 101 may include: a processor 201 and a memory 202 .
  • the processor 201 and the memory 202 are electrically connected directly or indirectly to realize data transmission or interaction.
  • electrical connections may be made through one or more communication buses or signal lines.
  • the processor 201 may be an integrated circuit chip, which has a signal processing capability.
  • the aforementioned processor 201 may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP) and the like.
  • CPU Central Processing Unit
  • NP Network Processor
  • Various methods, steps, and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed.
  • a general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.
  • Memory 202 can be, but not limited to, random access memory (Random Access Memory, RAM), read-only memory (Read Only Memory, ROM), programmable read-only memory (Programmable Read-Only Memory, PROM), erasable Read-only memory (Erasable Programmable Read-Only Memory, EPROM), Electric Erasable Programmable Read-Only Memory (EEPROM), etc.
  • RAM Random Access Memory
  • ROM read-only memory
  • PROM programmable read-only memory
  • PROM Programmable Read-Only Memory
  • EPROM Erasable Programmable Read-Only Memory
  • EEPROM Electric Erasable Programmable Read-Only Memory
  • the memory 202 is used to store programs, and the processor 201 invokes the programs stored in the memory 202 to execute the photovoltaic power generation system control method provided in the following embodiments.
  • FIG. 2 is only for illustration, and the power optimizer may also include more or less components than those shown in FIG. 2 , or have a configuration different from that shown in FIG. 2 .
  • Each component shown in Fig. 2 may be implemented by hardware, software or a combination thereof.
  • Fig. 3 is a schematic flowchart of a control method for a photovoltaic power generation system provided by an embodiment of the present application; the execution subject of the method may be the power optimizer shown in Fig. 1 and Fig. 2 above, and as shown in Fig. 3 , the method may include :
  • the photovoltaic panel under the irradiation of sunlight, the photovoltaic panel will generate voltage and current by itself, transmit them to the power optimizer through wires, and serve as the input voltage Uin and input current Iin of the power optimizer.
  • the first mapping curve can be used to indicate the corresponding relationship between the output voltage and the output power of the power optimizer, and the first mapping curve can include: a linear power curve in the first voltage segment and a linear power curve in the second voltage segment, wherein the second The voltage corresponding to the voltage segment may be higher than the voltage corresponding to the first voltage segment.
  • Pomax the maximum limited power of the power optimizer
  • a first MPPT unit is provided inside the power optimizer, and the first MPPT unit disturbs the input voltage Uin to seek the maximum power point when the photovoltaic panel is working.
  • the maximum power and the maximum limited power of the power optimizer can be used to obtain the output power Po and output voltage Uo of the "power optimizer".
  • the power optimizer can detect its own output voltage Uo in real time, that is, the bus voltage at both ends of DC+ and DC- of the photovoltaic inverter, but the "second MPPT unit" in the photovoltaic inverter will detect the voltage at both ends of DC+ and DC- The bus voltage at the terminal is disturbed, so that the bus voltage changes to seek the target maximum power of the photovoltaic power generation system.
  • Figure 4 is a schematic diagram of the external characteristic curve of the output voltage and output power of the power optimizer in the related art; as shown in Figure 4, in the related art, the external characteristic curve between the output voltage Uo and the output power Po of the power optimizer is: Vo1 to Vo4 constant power curves, where the abscissa is the output voltage Uo of the power optimizer, and the ordinate is the ratio of the output power Po of the power optimizer to the maximum limited power Pomax, ie Po/Pomax.
  • the MPPT unit in the power optimizer performs When the disturbance traces the maximum power point, the output power Po will jump from constant power to 0, causing the power optimizer to enter the cut-off zone, and the downstream photovoltaic inverter cannot work normally, that is, the power optimizer and photovoltaic inverter
  • the device has a mismatch oscillation.
  • this application proposes to adjust the external characteristics of the power-voltage relationship curve of the high and low voltage section of the power optimizer, which can effectively solve the problem that when the first MPPT unit in the power optimizer is disturbed at the point near Vo1 (or Vo4),
  • the phenomenon that the output power Po of the power optimizer jumps from constant power to 0 makes the power optimizer automatically adapt to the disturbance voltage change of the "photovoltaic inverter" connected to the subsequent stage, thus effectively balancing the "power optimizer” and "photovoltaic inverter". Inverters" to avoid the situation of mismatch oscillation.
  • the power optimizer can obtain the output power Po of the power optimizer according to the relationship between its actual input power and the pre-generated first mapping curve.
  • the bus voltage (DC+, DC-) corresponding to the output power refers to the output voltage Uo corresponding to the output power Po of the power optimizer.
  • the power optimizer outputs the output voltage Uo corresponding to its own output power Po to the subsequent photovoltaic inverter, and the second MPPT unit in the subsequent photovoltaic inverter disturbs the bus voltage to Get the target maximum power of the photovoltaic power generation system.
  • the embodiment of the present application provides a photovoltaic power generation system control method, which may include: obtaining the input current and input voltage of the power optimizer; obtaining the actual input power according to the input voltage and input current; obtaining the actual input power according to the actual input power and the pre-generated first mapping curve to obtain the output power; wherein, the first mapping curve is used to indicate the corresponding relationship between the output voltage and the output power of the power optimizer, and the first mapping curve includes: the first voltage segment linear power curve and the first The linear power curve of two voltage segments, wherein, the voltage corresponding to the second voltage segment is higher than the voltage corresponding to the first voltage segment; the bus voltage corresponding to the output power is output to the subsequent photovoltaic inverter, so that the subsequent photovoltaic inverter According to the bus voltage, determine the target maximum power.
  • the external characteristics of the power-voltage relationship curve of the high-voltage and low-voltage sections of the power optimizer are adjusted, so that when the first MPPT unit is disturbed at the point near Vo1 (or Vo4), it can be based on the actual input power, pre-determined Generate the first mapping curve to obtain the output power, and output the bus voltage corresponding to the output power to the subsequent photovoltaic inverter, so that the latter photovoltaic inverter can disturb the bus voltage to obtain the target maximum power of the photovoltaic power generation system , effectively solve the phenomenon that the output power Po of the power optimizer jumps from constant power to 0 when the first MPPT unit in the power optimizer is disturbed at a point near Vo1 (or Vo4), so that the power optimizer can automatically adapt to the subsequent stage
  • the disturbance voltage change of the connected "photovoltaic inverter" effectively balances the competitive relationship between the "power optimizer" and "photovoltaic inverter", and avoids the situation of mismatch oscillation.
  • the output power may also include:
  • Fig. 5 is a schematic diagram of an external characteristic curve of output voltage and output power of a power optimizer provided by an embodiment of the present application; as shown in Fig. 5 , the first mapping curve may also include: a third voltage section constant power section, wherein, The voltage corresponding to the third voltage range may be higher than the voltage corresponding to the first voltage range, and may be lower than the voltage corresponding to the second voltage range.
  • the linear power curve of the first voltage segment can be a linear curve in which the power increases with the increase of the voltage or the power decreases with the decrease of the voltage
  • the linear power curve of the second voltage segment can be a linear curve in which the power decreases with the increase of the voltage or the power decreases with the decrease of the voltage Rising linear curve.
  • the first voltage section can be from Vo1 to V02.
  • the relationship between the output power Po of the power optimizer and the output voltage Uo can be a positive correlation linear curve, that is, the output power Po of the power optimizer varies with It can also be understood that the output power Po of the power optimizer increases with the increase of the output voltage Uo.
  • the output voltage Uo detected by the power optimizer is within the first voltage range Vo1 to V02
  • the bus voltage currently disturbed by the second MPPT unit in the photovoltaic optimizer is within the first voltage range Vo1 to V02.
  • the output power Po of the power optimizer decreases with the decrease of the output voltage Uo, that is, it can be determined that the current disturbance direction is wrong, The next cycle is disturbed in the opposite direction. After multiple disturbances and observations, the tracking of the maximum output power point of the power optimizer can be realized.
  • the second voltage section can be from Vo3 to V04.
  • the relationship between the output power Po of the power optimizer and the output voltage Uo is a negative correlation linear curve, that is, the output power Po of the power optimizer increases with The increase of the output voltage Uo decreases, it can also be understood that the output power Po of the power optimizer increases with the decrease of the output voltage.
  • the output voltage Uo detected by the power optimizer is within the second voltage range Vo3 to V04
  • the bus voltage currently disturbed by the second MPPT unit in the photovoltaic optimizer is within the second voltage range Vo3 to V04.
  • the output power Po of the power optimizer decreases with the increase of the output voltage Uo, that is, it can be determined that the current disturbance direction is wrong, The next cycle is disturbed in the opposite direction. After multiple disturbances and observations, the tracking of the maximum output power point of the power optimizer can be realized.
  • using the linear power curve of the first voltage segment and the linear power curve of the second voltage segment in the first mapping curve can prevent the output power Po of the first MPPT unit in the power optimizer during the disturbance process. In the case of jumping to 0, when the output voltage Uo exceeds the output voltage range, it will cause the protection or voltage limit control mechanism of the power optimizer.
  • the third voltage section can be from Vo2 to V03. In the third voltage section, it is a constant power curve, that is, the output power Po of the power optimizer does not change with the increase (or decrease) of the output voltage Uo, and the output power of the power optimizer
  • the power Po is a constant value.
  • the output voltage Uo detected by the power optimizer is within the third voltage range Vo2 to V03, it can also be understood that the bus voltage currently disturbed by the second MPPT unit in the photovoltaic optimizer is within the third voltage range Vo2 to V03.
  • the first MPPT unit in the power optimizer is disturbed in the third voltage segment, it will be found that the output power Po of the power optimizer does not change with the increase of the output voltage Uo, that is, according to the third voltage segment
  • the constant power and the actual input power of the power optimizer determine the output power of the power optimizer.
  • V01 and V04 must be included in the input range of the bus voltage (DC+, DC-) of the downstream photovoltaic inverter, otherwise it will affect the normal operation of the downstream photovoltaic inverter.
  • the specific values of V01 and V04 can be determined according to the input range of commonly used photovoltaic inverters, and it is recommended to meet the input range requirements of most photovoltaic inverters.
  • the slope of the linear power curve of the first voltage segment and the linear power curve of the second voltage segment should not be set too steep, so as not to cause oscillation.
  • the step S303 above, obtaining the output power according to the actual input power and the pre-generated first mapping curve may include:
  • the output power can be obtained according to the linear power curve of the first voltage segment or the linear power curve of the second voltage segment .
  • the power optimizer detects that the bus voltage (DC+, DC-) after the disturbance of the downstream photovoltaic inverter is V1 in Figure 5, in the first voltage range Vo1 to V02, that is, the power optimizer
  • the output power can be obtained according to the linear power curve of the second voltage range.
  • the actual maximum photovoltaic input power is less than the maximum constant power value of the power optimizer, such as k is less than 1
  • the actual working area is the area below the intersection of the dotted line of the k value and the external characteristics. Since the k value must intersect with the linear power curve of the first voltage segment or the linear power curve of the second voltage segment, there is a maximum power interval. If it is detected that the bus voltage after the disturbance of the downstream photovoltaic inverter is running in the first voltage range Vo1-Vo2 or the second voltage range Vo3-Vo4, it can also be understood that the second MPPT in the downstream photovoltaic inverter The unit disturbance flies out of the constant power section.
  • the power optimizer enters the high-voltage and low-voltage limited power sections, that is, the output power Po of the power optimizer can be obtained according to the linear power curve of the first voltage section or the linear power curve of the second voltage section. , which limits the output power Po of the power optimizer.
  • step S303 above, obtaining the output power according to the actual input power and the pre-generated first mapping curve may also include:
  • the output power can be obtained according to the constant power segment of the third voltage segment.
  • the actual input power Pin is less than the maximum limited power Pomax of the power optimizer, the actual input power is taken as the output power.
  • the maximum limited power is taken as the output power.
  • the actual input power Pin of the power optimizer and “the output power of the photovoltaic panel” are the same concept.
  • the actual output power of photovoltaic panels may be greater than or less than the maximum limited power Pomax of the power optimizer, if the output power of photovoltaic panels is greater than or equal to the maximum limited power Pomax of the power optimizer , then the output power Po of the power optimizer is equal to the maximum limited power Pomax; if the maximum output capability of the photovoltaic panel is less than the maximum limited power Pomax of the power optimizer (the ratio is less than 1), then the output power Po of the power optimizer is equal to the photovoltaic panel
  • the maximum power of the photovoltaic panel can be tracked by the first MPPT unit in the power optimizer.
  • the power optimization when the bus voltage after the disturbance of the downstream photovoltaic inverter is detected and is within the third voltage range Vo2-Vo3 (that is, when the output voltage of the power optimizer is between Vo2-Vo3), the power optimization The minimum value of the "actual input power” and “maximum limited power Pomax" of the power optimizer is used as the output power Po of the power optimizer.
  • Fig. 6 is a schematic flowchart of another photovoltaic power generation system control method provided by the embodiment of the present application; optionally, as shown in Fig. 6, in the above step 303, according to the actual input power and the pre-generated first mapping curve, the After output power, it can also include:
  • the maximum power point is obtained by perturbing the maximum power point unit in the power optimizer according to the input voltage and input current.
  • the maximum power point unit can also be understood as the first MPPT unit set in the power optimizer, the input voltage and input current of the power optimizer, that is, the voltage and current generated by the photovoltaic panel.
  • Fig. 7 is a schematic diagram of the working principle of the MPPT unit and the output voltage power limiting loop in the power optimizer in a photovoltaic power generation system control method provided by the embodiment of the present application.
  • the first MPPT unit produces a The voltage and current are perturbed and tracked to the maximum power point of the photovoltaic panel, as well as the given voltage Vin* corresponding to the maximum power point, and the given voltage Vin* is transmitted to the input voltage inner loop, so that the given voltage Vin* can be , to determine the first given current I1*.
  • S602. Determine a second given current according to the output power and the output voltage corresponding to the output power.
  • the output power Po corresponding to the output voltage Uo is obtained, and the second given current I2* is calculated by the output voltage limiting power loop .
  • the current loop controller can use the minimum given current to realize the change of the duty ratio D of the MOSFET, thereby generating a disturbance of the current to achieve the purpose of stabilizing the output voltage.
  • Fig. 8 is a schematic flowchart of a photovoltaic power generation system control method provided in the embodiment of the present application; optionally, as shown in Fig. 7, the method may include:
  • FIG. 9 is a schematic structural diagram of a photovoltaic power generation system control device provided by an embodiment of the present application; as shown in FIG.
  • the obtaining module 901 may be configured to obtain the input current and input voltage of the power optimizer
  • the processing module 902 may be configured to obtain actual input power according to the input voltage and input current; obtain output power according to the actual input power and a pre-generated first mapping curve; wherein, the first mapping curve may be used to indicate power optimization
  • the corresponding relationship between the output voltage of the converter and the output power, the first mapping curve may include: a linear power curve of the first voltage segment and a linear power curve of the second voltage segment, wherein the voltage corresponding to the second voltage segment may be higher than that of the first voltage segment Corresponding voltage;
  • the determination module 903 may be configured to output the bus voltage corresponding to the output power to the subsequent photovoltaic inverter, so that the latter photovoltaic inverter determines the target maximum power according to the bus voltage.
  • the first mapping curve may further include: a third voltage segment constant power segment, wherein the voltage corresponding to the third voltage segment may be higher than the voltage corresponding to the first voltage segment, and may be lower than the voltage corresponding to the second voltage segment Voltage;
  • the linear power curve in the first voltage segment may be a linear curve in which power increases with increasing voltage
  • the linear power curve in the second voltage segment may be a linear curve in which power decreases with increasing voltage
  • processing module 902 may also be configured to:
  • the output power can be obtained according to the linear power curve of the first voltage segment or the linear power curve of the second voltage segment .
  • processing module 902 may also be configured to:
  • the output power can be obtained according to the constant power segment of the third voltage segment.
  • processing module 902 may also be configured to:
  • the actual input power is less than or equal to the maximum limited power of the power optimizer, the actual input power is taken as the output power.
  • processing module 902 may also be configured to:
  • the maximum limited power is taken as the output power.
  • the device may also include: an adjustment module;
  • the adjustment module may be configured to adjust the corresponding relationship between the first voltage segment, the second voltage segment and the output power respectively to obtain the first mapping curve.
  • the adjustment module can also be configured for:
  • the corresponding relationship between the second voltage segment and the output power is adjusted to a linear relationship in which the power decreases as the voltage increases.
  • processing module 902 may also be configured to:
  • the maximum power point and the given voltage corresponding to the maximum power point determine the first given current; wherein, the maximum power point is the maximum power point unit in the power optimizer, which is obtained by perturbing the input voltage and the input current; according to The output power and the output voltage corresponding to the output power determine the second given current; according to the first given current and the second given current, the minimum given current is obtained;
  • the apparatus may also include an adjustment module configurable to adjust a duty cycle of the power optimizer using a minimum given current.
  • the above modules may be one or more integrated circuits configured to implement the above method, for example: one or more specific integrated circuits (Application Specific Integrated Circuit, referred to as ASIC), or, one or more microprocessors (digital singnal processor, DSP for short), or, one or more Field Programmable Gate Arrays (Field Programmable Gate Array, FPGA for short), etc.
  • ASIC Application Specific Integrated Circuit
  • DSP digital singnal processor
  • FPGA Field Programmable Gate Array
  • the processing element may be a general-purpose processor, such as a central processing unit (Central Processing Unit, referred to as CPU) or other processors that can call program codes.
  • CPU central processing unit
  • these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC for short).
  • the present application further provides a program product, such as a computer-readable storage medium, which may include a program, and the program is used to execute the foregoing method embodiments when executed by a processor.
  • a program product such as a computer-readable storage medium, which may include a program, and the program is used to execute the foregoing method embodiments when executed by a processor.
  • the disclosed devices and methods may be implemented in other ways.
  • the device embodiments described above are only illustrative.
  • the division of the units is only a logical function division. In actual implementation, there may be other division methods.
  • multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented.
  • the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.
  • the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.
  • each functional unit in each embodiment of the present application may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.
  • the above-mentioned integrated units can be implemented in the form of hardware, or in the form of hardware plus software functional units.
  • the above-mentioned integrated units implemented in the form of software functional units may be stored in a computer-readable storage medium.
  • the above-mentioned software functional units are stored in a storage medium, and include several instructions to enable a computer device (which may be a personal computer, server, or network device, etc.) or a processor (English: processor) to execute the functions described in various embodiments of the present application. part of the method.
  • the aforementioned storage media include: U disk, mobile hard disk, read-only memory (English: Read-Only Memory, abbreviated: ROM), random access memory (English: Random Access Memory, abbreviated: RAM), magnetic disk or optical disc, etc.
  • ROM Read-Only Memory
  • RAM Random Access Memory
  • magnetic disk or optical disc etc.
  • the application provides a photovoltaic power generation system control method, device, power optimizer and storage medium.
  • the method includes: obtaining the input current and the input voltage of the power optimizer; obtaining the actual input power according to the input voltage and the input current; obtaining the output power according to the actual input power and the pre-generated first mapping curve; the first mapping curve is used for Indicates the corresponding relationship between the output voltage of the power optimizer and the output power.
  • the first mapping curve includes: the linear power curve of the first voltage segment and the linear power curve of the second voltage segment.
  • the voltage corresponding to the second voltage segment is higher than that corresponding to the first voltage segment output voltage corresponding to the output power to the post-stage photovoltaic inverter, so that the post-stage photovoltaic inverter can determine the target maximum power according to the bus voltage.
  • the photovoltaic power generation system control method, device, power optimizer and storage medium of the present application are reproducible and can be used in various industrial applications.
  • the photovoltaic power generation system control method, device, power optimizer and storage medium of the present application can be used in the technical field of power electronics.

Abstract

本申请提供一种光伏发电系统控制方法、装置、功率优化器及存储介质，涉及电力电子技术领域。该方法包括：获取功率优化器的输入电流和输入电压；根据输入电压和输入电流，得到实际输入功率；根据实际输入功率以及预先生成的第一映射曲线，得到输出功率；第一映射曲线用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，第二电压段对应的电压高于第一电压段对应的电压；将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器根据母线电压，确定目标最大功率。本方案，能够有效平衡功率优化器和光伏逆变器之间的竞争关系，避免出现失配震荡的情况。

Description

光伏发电系统控制方法、装置、功率优化器及存储介质
相关申请的交叉引用
本申请要求于2021年06月25日提交中国国家知识产权局的申请号为2021107108498、名称为“光伏发电系统控制方法、装置、功率优化器及存储介质”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及电力电子技术领域，具体而言，涉及一种光伏发电系统控制方法、装置、功率优化器及存储介质。
背景技术
光伏发电是利用半导体界面的光生伏特效应而将光能直接转变为电能的一种技术。主要由光伏电池板(组件)、控制器和逆变器三大部分组成，主要部件由电子元器件构成。太阳能电池经过串联后进行封装保护可形成大面积的太阳电池组件，再配合上功率控制器等部件就形成了光伏发电装置。
目前，在光伏发电系统中，包括集中式和分布式系统。其中，集中式光伏系统中，一般是由光伏电池板串联形成高压输入给光伏逆变器，光伏逆变器执行最大功率点跟踪(Maximum Power Point Tracking，简称MPPT)功能；在分布式光伏系统中，光伏逆变器由两级构成，前级DC/DC完成升压和MPPT功能，后级完成稳定输入电压和逆变功能。另外，对于目前的集中式和分布式系统，若光伏电池板设置有功率优化器时，则功率优化器的后级接入光伏逆变器，由功率优化器执行升压、隔离、MPPT等功能，光伏逆变器完成稳定输入电压和逆变等功能。
但是，在相关技术的光伏发电系统中，只考虑由“功率优化器”或者“光伏逆变器”中某一模块执行MPPT功能的情况，但当“光伏逆变器”进行MPPT追踪，“功率优化器”DC/DC也同时进行MPPT追踪时，则整个系统就存在两个MPPT的DC/DC单元，且这两级MPPT的DC/DC单元都在通过扰动策略试图寻求最大功率点，进而会导致两级MPPT可能存在一定的竞争关系，甚至可能会出现失配震荡。
发明内容
本申请提供了一种光伏发电系统控制方法、装置、功率优化器及存储介质，以便平衡功率优化器和光伏逆变器之间的竞争关系，避免出现失配震荡的情况，从而至少克服了以上所提及的相关技术中的不足。
本申请的一些实施例提供了一种光伏发电系统控制方法，应用于光伏发电系统中的功率优化器，该光伏发电系统控制方法可以包括：
获取功率优化器的输入电流和输入电压；
根据所述输入电压和所述输入电流，得到实际输入功率；
根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，所述第一映射曲线用于指示所述功率优化器的输出电压与输出功率的对应关系，所述第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，所述第二电压段对应的电压高于所述第一电压段对应的电压；
将所述输出功率对应的母线电压输出至后级光伏逆变器，以使得所述后级光伏逆变器根据所述母线电压，确定目标最大功率。
可选地，所述第一映射曲线还可以包括：第三电压段恒定功率段，其中，所述第三电压段对应的电压可以高于所述第一电压段对应的电压，且低于所述第二电压段对应的电压；
所述第一电压段线性功率曲线可以为功率随电压升高而升高或功率随电压降低而降低的线性曲线，所述第二电压段线性功率曲线可以为功率随电压升高而降低或功率随电压降低而升高的线性曲线。
可选地，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率，可以包括：
若检测到所述后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则可以根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
可选地，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率，还可以包括：
若检测到所述后级光伏逆变器扰动后的母线电压，在第三电压段内时，则可以根据第三电压段恒定功率段，得到输出功率。
可选地，所述根据第三电压段恒定功率段，得到输出功率，可以包括：
若所述实际输入功率小于或等于所述功率优化器的最大限定功率，则可以将所述实际输入功率作为输出功率。
可选地，所述根据第三电压段恒定功率段，得到输出功率，还可以包括：
若所述实际输入功率大于所述最大限定功率，则可以将所述最大限定功率作为输出功率。
可选地，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率之前，还可以包括：
分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到所述第一映射曲线。
可选地，所述分别对第一电压段、第二电压段与输出功率的对应关系进行调整，可以包括：
将第一电压段与输出功率的对应关系调整为功率随电压升高而升高的线性关系；
将第二电压段与输出功率的对应关系调整为功率随电压升高而降低的线性关系。
可选地，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率之后，还可以包括：
根据最大功率点、及所述最大功率点对应的给定电压，确定第一给定电流；其中，所述最大功率点是所述功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的；
根据所述输出功率、所述输出功率对应的输出电压，确定第二给定电流；
根据所述第一给定电流、所述第二给定电流，得到最小给定电流；
使用所述最小给定电流，调节所述功率优化器的占空比。
本申请的另一些实施例还提供了一种光伏发电系统控制装置，所述伏发电系统控制装置可以包括：获取模块、处理模块、确定模块；
所述获取模块，可以配置成用于获取功率优化器的输入电流和输入电压；
所述处理模块，可以配置成用于根据所述输入电压和所述输入电流，得到实际输入功率；根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，所述第一映射曲线用于指示所述功率优化器的输出电压与输出功率的对应关系，所述第一映射曲线可以包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，所述第二电压段对应的电压可以高于所述第一电压段对应的电压；
所述确定模块，可以配置成用于将所述输出功率对应的母线电压输出至后级光伏逆变器，以使得所述后级光伏逆变器根据所述母线电压，确定目标最大功率。
可选地，所述第一映射曲线还可以包括：第三电压段恒定功率段，其中，所述第三电压段对应的电压可以高于所述第一电压段对应的电压，且可以低于所述第二电压段对应的电压；
所述第一电压段线性功率曲线可以为功率随电压升高而升高或功率随电压降低而降低的线性曲线，所述第二电压段线性功率曲线可以为功率随电压升高而降低或功率随电压降低而升高的线性曲线。
可选地，所述处理模块，还可以配置成用于：
若检测到所述后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
可选地，所述处理模块，还可以配置成用于：
若检测到所述后级光伏逆变器扰动后的母线电压，在第三电压段内时，则根据第三电压段恒定功率段，得到输出功率。
可选地，所述处理模块，还可以配置成用于：
若所述实际输入功率小于或等于所述功率优化器的最大限定功率，则将所述实际输入功率作为输出功率。
可选地，所述处理模块，还可以配置成用于：
若所述实际输入功率大于所述最大限定功率，则将所述最大限定功率作为输出功率。
可选地，所述装置还可以包括：调整模块；
所述调整模块，可以配置成用于分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到所述第一映射曲线。
可选地，所述调整模块，还可以配置成用于：
将第一电压段与输出功率的对应关系调整为功率随电压升高而升高的线性关系；
将第二电压段与输出功率的对应关系调整为功率随电压升高而降低的线性关系。
可选地，所述处理模块，还可以配置成用于：
根据最大功率点、及所述最大功率点对应的给定电压，确定第一给定电流；其中，所述最大功率点是所述功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的；根据所述输出功率、所述输出功率对应的输出电压，确定第二给定电流；根据所述第一给定电流、所述第二给定电流，得到最小给定电流；
所述装置还可以包括：调节模块，所述调节模块，可以配置成用于使用所述最小给定电流，调节所述功率优化器的占空比。
本申请的又一些实施例还提供了一种功率优化器，可以包括：处理器、存储介质和总线，所述存储介质存储有所述处理器可执行的机器可读指令，当功率优化器运行时，所述处理器与所述存储介质之间通过总线通信，所述处理器执行所述机器可读指令，以执行如上述实施例所提供的所述光伏发电系统控制方法的步骤。
本申请的再一些实施例还提供了一种计算机可读存储介质，所述存储介质上存储有计算机程序，所述计算机程序被处理器运行时执行上述实施例所提供的所述光伏发电系统控制方法的步骤。
本申请的有益效果至少是：
本申请实施例提供一种光伏发电系统控制方法、装置、功率优化器及存储介质，该方法包括：获取功率优化器的输入电流和输入电压；根据输入电压和输入电流，得到实际输入功率；根据实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，第一映射曲线用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，第二电压段对应的电压高于第一电压段对应的电压；将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏 逆变器根据母线电压，确定目标最大功率。在本方案中，对功率优化器的高低压段的功率与电压关系曲线的外特性进行了调整，使得第一MPPT单元在Vo1(或Vo4)临近点进行扰动时，可以根据实际输入功率、预先生成的第一映射曲线，得到输出功率，并将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器对母线电压进行扰动，得到光伏发电系统的目标最大功率，有效解决功率优化器中的第一MPPT单元在Vo1(或Vo4)临近点进行扰动时，出现功率优化器的输出功率Po从恒功率跳跃至0的现象，使得功率优化器能够自动适应后级连接的“光伏逆变器”的扰动电压变化，从而有效平衡了“功率优化器”和“光伏逆变器”之间的竞争关系，避免出现失配震荡的情况。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，应当理解，以下附图仅示出了本申请的某些实施例，因此不应被看作是对范围的限定，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他相关的附图。
图1为本申请实施例提供的一种光伏发电系统的结构示意图；
图2为本申请实施例提供的一种功率优化器的结构示意图；
图3为本申请实施例提供的一种光伏发电系统控制方法的流程示意图；
图4为相关技术中功率优化器的输出电压与输出功率的外特性曲线示意图；
图5为本申请实施例提供的一种功率优化器的输出电压与输出功率的外特性曲线示意图；
图6为本申请实施例提供的另一种光伏发电系统控制方法的流程示意图；
图7为本申请实施例提供的一种光伏发电系统控制方法中功率优化器中MPPT单元与输出电压限功率环的工作原理示意图；
图8为本申请实施例提供的一种光伏发电系统控制方法的整体流程示意图；
图9为本申请实施例提供的一种光伏发电系统控制装置的结构示意图。
图标：100-光伏发电系统；101-功率优化器；102-光伏逆变器。
具体实施方式
为使本申请实施例的目的、技术方案和优点更加清楚，下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，应当理解，本申请中附图仅起到说明和描述的目的，并不用于限定本申请的保护范围。另外，应当理解，示意性的附图并未按实物比例绘制。本申请中使用的流程图示出了根据本申请的一些实施例实现的操作。应该理解，流程图的操作可以不按顺序实现，没有逻辑的上下文关系的步骤可以反转顺序或者同时实施。此外，本领域技术人员在本申请内容的指引下，可以向流程图添加一 个或多个其他操作，也可以从流程图中移除一个或多个操作。
另外，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。通常在此处附图中描述和示出的本申请实施例的组件可以以各种不同的配置来布置和设计。因此，以下对在附图中提供的本申请的实施例的详细描述并非旨在限制要求保护的本申请的范围，而是仅仅表示本申请的选定实施例。基于本申请的实施例，本领域技术人员在没有做出创造性劳动的前提下所获得的所有其他实施例，都属于本申请保护的范围。
需要说明的是，本申请实施例中将会用到术语“包括”，用于指出其后所声明的特征的存在，但并不排除增加其它的特征。
首先，在对本申请所提供的技术方案展开具体说明之前，先对本申请所涉及到MPPT单元的工作原理进行简单说明。
MPPT单元的工作原理：实时侦测光伏电池板的发电电压和电流，并通过测量扰动前后光伏电池板的输出功率和电压的变化，以决定下一周期的扰动方向，当扰动方向正确时光伏电池板的输出功率增加，下周期继续朝同一方向扰动，反之，朝反方向扰动，如此，反复进行着扰动与观察，以实现对光伏电池板最大功率点的追踪。
其次，再对本申请所要解决的技术问题进行简单说明。
相关技术中，“功率优化器”和“光伏逆变器”是由不同厂家设计制造，只考虑由光伏发电系统中的“功率优化器”或者“光伏逆变器”根据光伏发电系统中的功率-电压特性曲线执行最大功率点跟踪，进而使得光伏发电系统能够工作在最大功率点以充分利用太阳能资源，达到提高光伏发电系统能量转换效率的目的。
但是，当光伏发电系统中同时设置有“功率优化器”和“光伏逆变器”时，“功率优化器”和“光伏逆变器”中的MPPT的DC/DC单元都在通过扰动策略试图寻求各自的最大功率点，即“功率优化器”和“光伏逆变器”之间存在的这种竞争关系可能会出现失配震荡。
因此，亟需要提出一种自适应配合策略的功率调节方法，以解决在“功率优化器”和“光伏逆变器”进行级联时，无论后级“光伏逆变器”带MPPT功能还是不带MPPT功能，均能够有效平衡“功率优化器”和“光伏逆变器”之间的竞争关系，避免出现失配震荡的情况。
本申请方案的发明构思在于：是对功率优化器的高低压段的功率与电压关系曲线进行了调整，以使得光伏发电系统中的“功率优化器”在寻求最大功率点时，能够自动适应后级连接的“光伏逆变器”的功率变化，从而有效平衡了“功率优化器”和“光伏逆变器”之间的竞争关系，避免出现失配震荡的情况。
如下，将通过多个具体实施例对本申请所提供的光伏发电系统方法的具体实现步骤和产生的有益效果进行说明。
图1为本申请实施例提供的一种光伏发电系统的结构示意图；如图1所示，该光伏发 电系统100可以包括：依次电连接的光伏电池板(PV-1、…、PV-n)、至少一个功率优化器101、光伏逆变器102。
如图1所示，本申请实施例提供的是分布式光伏发电系统，功率优化器101可以采用多路隔离升压方案，多路独立运行MPPT，跟踪每块光伏电池板的最大功率，转换效率高，输出并联组网。
例如，在光伏发电系统100中，光伏电池板(PV-1、…、PV-n)可以连接至功率优化器101，光伏电池板将产生的电压和电流输入给功率优化器，且每个功率优化器101是采用输入独立运行MPPT，以便于功率优化器101能够实时侦测光伏电池板的发电电压，并根据本申请提供的光伏发电系统控制方法，得到功率优化器101的实际输出功率，多个功率优化器将各自的输出电压并联输出组成直流母线电压(DC+、DC-)，光伏逆变器102根据直流母线电压，得到光伏发电系统100的目标最大功率，最后，光伏逆变器102将目标最大功率对应的直流电压转换为交流电压并网输出。
图2为本申请实施例提供的一种功率优化器的结构示意图；如图2所示，该功率优化器101可以包括：处理器201和存储器202。
处理器201、存储器202之间直接或间接地电性连接，以实现数据的传输或交互。例如，可通过一条或多条通信总线或信号线实现电性连接。
其中，处理器201可以是一种集成电路芯片，具有信号的处理能力。上述的处理器201可以是通用处理器，包括中央处理器(Central Processing Unit，CPU)、网络处理器(Network Processor，NP)等。可以实现或者执行本申请实施例中的公开的各方法、步骤及逻辑框图。通用处理器可以是微处理器或者该处理器也可以是任何常规的处理器等。
存储器202可以是，但不限于，随机存取存储器(Random Access Memory，RAM)，只读存储器(Read Only Memory，ROM)，可编程只读存储器(Programmable Read-Only Memory，PROM)，可擦除只读存储器(Erasable Programmable Read-Only Memory，EPROM)，电可擦除只读存储器(Electric Erasable Programmable Read-Only Memory，EEPROM)等。
其中，存储器202用于存储程序，处理器201调用存储器202存储的程序，以执行下面实施例提供的光伏发电系统控制方法。
可以理解，图2所述的结构仅为示意，功率优化器还可包括比图2中所示更多或者更少的组件，或者具有与图2所示不同的配置。图2中所示的各组件可以采用硬件、软件或其组合实现。
如下将通过多个具体的实施例对本申请所提供的光伏发电系统控制方法的实现原理和对应产生的有益效果进行说明。
图3为本申请实施例提供的一种光伏发电系统控制方法的流程示意图；该方法的执行 主体可以是上述图1和图2所示的功率优化器，如图3所示，该方法可包括：
S301、获取功率优化器的输入电流和输入电压。
S302、根据输入电压和输入电流，得到实际输入功率。
参考图1，在太阳光的照射下，光伏电池板将自身产生电压和电流，通过导线传输至功率优化器，并作为功率优化器的输入电压Uin和输入电流Iin。功率优化器根据接收到的输入电压Uin和输入电流Iin，计算得到功率优化器的实际输入功率Pin＝Uin*Iin。
S303、根据实际输入功率以及预先生成的第一映射曲线，得到输出功率。
其中，第一映射曲线可以用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线可以包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，第二电压段对应的电压可以高于第一电压段对应的电压。
其中，将功率优化器的最大限定功率记作Pomax。
需要说明的是，对光伏发电系统中“功率优化器”的输出电压Uo与“光伏逆变器”的母线电压的关系进行简单说明。
1、在本实施例中，功率优化器的内部设置有第一MPPT单元，第一MPPT单元对输入电压Uin进行扰动，以寻求光伏电池板工作时的最大功率点，根据光伏电池板工作时的最大功率与功率优化器的最大限定功率，可以得到“功率优化器”的输出功率Po、输出电压Uo。
2、功率优化器可以实时检测自身的输出电压Uo，也就是光伏逆变器的DC+、DC-两端的母线电压，但光伏逆变器中的“第二MPPT单元”会对DC+、DC-两端的母线电压进行扰动，使得母线电压发生变化，以寻求光伏发电系统的目标最大功率。
图4为相关技术中功率优化器的输出电压与输出功率的外特性曲线示意图；如图4所示，在相关技术中，功率优化器的输出电压Uo与输出功率Po之间的外特性曲线为Vo1到Vo4恒功率曲线，其中，横坐标是功率优化器的输出电压Uo，纵坐标是功率优化器的输出功率Po与最大限定功率Pomax的比值，即Po/Pomax。
但是，当功率优化器检测到光伏逆变器当前扰动的母线电压(DC+、DC-)在Vo1(或Vo4)点时，进一步地，功率优化器中的MPPT单元在Vo1(或Vo4)点进行扰动追踪最大功率点时，会出现输出功率Po从恒功率跳跃至0的现象，导致功率优化器进入截止区，后级光伏逆变器也无法进行正常的工作，即功率优化器和光伏逆变器出现了失配震荡的情况。
因此，本申请提出对功率优化器的高低压段的功率与电压关系曲线的外特性进行了调整，可以有效解决功率优化器中的第一MPPT单元在Vo1(或Vo4)临近点进行扰动时，出现功率优化器的输出功率Po从恒功率跳跃至0的现象，使得功率优化器自动适应后级连接的“光伏逆变器”的扰动电压变化，从而有效平衡了“功率优化器”和“光伏逆变器”之间的竞争关系，避免出现失配震荡的情况。
基于上述分析，在本实施例中，功率优化器可以根据自身的实际输入功率、预先先生成的第一映射曲线的关系，得到功率优化器的输出功率Po。
S304、将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器根据母线电压，确定目标最大功率。
其中，输出功率对应的母线电压(DC+、DC-)是指：功率优化器的输出功率Po对应的输出电压Uo。
在上述实施例的基础上，功率优化器将自身的输出功率Po对应的输出电压Uo输出至后级光伏逆变器，后级光伏逆变器中的第二MPPT单元对母线电压进行扰动，以得到光伏发电系统的目标最大功率。
综上所述，本申请实施例提供一种光伏发电系统控制方法，该方法可以包括：获取功率优化器的输入电流和输入电压；根据输入电压和输入电流，得到实际输入功率；根据实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，第一映射曲线用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，第二电压段对应的电压高于第一电压段对应的电压；将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器根据母线电压，确定目标最大功率。在本方案中，对功率优化器的高低压段的功率与电压关系曲线的外特性进行了调整，使得第一MPPT单元在Vo1(或Vo4)临近点进行扰动时，可以根据实际输入功率、预先生成的第一映射曲线，得到输出功率，并将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器对母线电压进行扰动，得到光伏发电系统的目标最大功率，有效解决功率优化器中的第一MPPT单元在Vo1(或Vo4)临近点进行扰动时，出现功率优化器的输出功率Po从恒功率跳跃至0的现象，使得功率优化器能够自动适应后级连接的“光伏逆变器”的扰动电压变化，从而有效平衡了“功率优化器”和“光伏逆变器”之间的竞争关系，避免出现失配震荡的情况。
将通过如下实施例具体讲解如何根据实际输入功率以及预先生成的第一映射曲线，得到输出功率。
可选地，根据实际输入功率以及预先生成的第一映射曲线，得到输出功率之前，还可以包括：
分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到第一映射曲线，使得功率优化器能够根据实际输入功率、预先生成的电压-功率的第一映射曲线，得到输出功率，达到平衡“功率优化器”和“光伏逆变器”竞争关系的目的，避免出现失配震荡的情况。
图5为本申请实施例提供的一种功率优化器的输出电压与输出功率的外特性曲线示意图；如图5所示，第一映射曲线还可以包括：第三电压段恒定功率段，其中，第三电压段 对应的电压可以高于第一电压段对应的电压，且可以低于第二电压段对应的电压。
第一电压段线性功率曲线可以为功率随电压升高而升高或功率随电压降低而降低的线性曲线，第二电压段线性功率曲线可以为功率随电压升高而降低或功率随电压降低而升高的线性曲线。
1、第一电压段可以是Vo1到V02，在第一电压段时，功率优化器的输出功率Po与输出电压Uo之间的关系可以为正相关线性曲线，即功率优化器的输出功率Po随着输出电压Uo的减小而降低，也可以理解为，功率优化器的输出功率Po随着输出电压Uo的增大而升高。
当功率优化器检测到的输出电压Uo在第一电压段Vo1到V02内时，也可以理解为，光伏优化器中的第二MPPT单元当前扰动的母线电压在第一电压段Vo1到V02内。此时，功率优化器中的第一MPPT单元在第一电压段内进行扰动时，会发现功率优化器的输出功率Po随着输出电压Uo的减小而降低，即可以确定当前扰动方向错误，下周期朝反方向扰动，经过多次扰动与观察，可以实现对功率优化器的最大输出功率点的追踪。
2、第二电压段可以是Vo3到V04，在第二电压段时，功率优化器的输出功率Po与输出电压Uo之间的关系为负相关线性曲线，即功率优化器的输出功率Po随着输出电压Uo的增大而降低，也可以理解为，功率优化器的输出功率Po随着输出电压的减小而升高。
当功率优化器检测到的输出电压Uo在第二电压段Vo3到V04内时，也可以理解为，光伏优化器中的第二MPPT单元当前扰动的母线电压在第二电压段Vo3到V04内。此时，功率优化器中的第一MPPT单元在第二电压段内进行扰动时，会发现功率优化器的输出功率Po随着输出电压Uo的增大而降低，即可以确定当前扰动方向错误，下周期朝反方向扰动，经过多次扰动与观察，可以实现对功率优化器的最大输出功率点的追踪。
在本实施例中，使用第一映射曲线中的第一电压段线性功率曲线和第二电压段线性功率曲线，可以避免功率优化器中的第一MPPT单元在扰动的过程中，出现输出功率Po跳跃至0的情况，这样可以使得当输出电压Uo超过输出电压范围时，则会引起功率优化器的保护或限压控制机制。
3、第三电压段可以是Vo2到V03，在第三电压段为恒功率曲线，即功率优化器的输出功率Po随着输出电压Uo的增大(或减小)而不变，功率优化器的输出功率Po是个恒定值。
当功率优化器检测到的输出电压Uo在第三电压段Vo2到V03内时，也可以理解为，光伏优化器中的第二MPPT单元当前扰动的母线电压在第三电压段Vo2到V03内。此时，功率优化器中的第一MPPT单元在第三电压段内进行扰动时，会发现功率优化器的输出功率Po随着输出电压Uo的增大而不变，即可以根据第三电压段的恒功率与功率优化器的实 际输入功率，确定功率优化器的输出功率。
需要说明的是，V01和V04必须包含在后级光伏逆变器的母线电压(DC+、DC-)的输入范围内，否则会影响后级光伏逆变器的正常工作。V01和V04的具体值可以根据常用光伏逆变器的输入范围确定参数，建议能适应大多数的光伏逆变器输入范围需求。另外，第一电压段线性功率曲线和第二电压段线性功率曲线的斜率不宜设置太陡，以免引起震荡。
可选地，上述步骤S303、根据实际输入功率以及预先生成的第一映射曲线，得到输出功率，可以包括：
若检测到后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则可以根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
具体的，例如，若功率优化器检测到后级光伏逆变器扰动后的母线电压(DC+、DC-)是图5中的V1，在第一电压段Vo1到V02时，即功率优化器的输出电压Uo＝V1，则根据第一电压段线性功率曲线，可以读取到功率优化器的输出电压V1对应的输出功率是Po＝k*Pomax。
同理，若检测到后级光伏逆变器扰动后的母线电压，在第二电压段内时，则可以根据第二电压段线性功率曲线，得到输出功率。
在本实施例中，若实际光伏输入最大功率小于功率优化器的最大恒功率值，如k小于1，实际工作区域为k值虚线与外特性交汇下方区域。由于k值必然与第一电压段线性功率曲线或第二电压段线性功率曲线相交，因此存在最大功率区间的。若检测到后级光伏逆变器扰动后的母线电压运行在第一电压段Vo1-Vo2或第二电压段Vo3-Vo4内时，也可以理解为，后级光伏逆变器中的第二MPPT单元扰动飞出恒功率区间段，此时，功率优化器进入高压和低压限功率段，即可以根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到功率优化器的输出功率Po，限制了功率优化器的输出功率Po。
可选地，上述步骤S303、根据实际输入功率以及预先生成的第一映射曲线，得到输出功率，还可以包括：
若检测到后级光伏逆变器扰动后的母线电压，在第三电压段内时，则可以根据第三电压段恒定功率段，得到输出功率。
例如，若功率优化器检测到后级光伏逆变器扰动后的母线电压(DC+、DC-)是图5中的V2，在第三电压段Vo2到V03时，即功率优化器的输出电压Uo＝V2，则根据第三电压段线性功率曲线，可以读取到功率优化器的输出电压V2对应的输出功率是Pomax。
但是，还需要对功率优化器的实际输入功率Pin和最大限定功率Pomax进行判断比较，以确定功率优化器的输出电压Uo＝V2时，最终的输出功率Po。
第一种情况，若实际输入功率Pin小于功率优化器的最大限定功率Pomax，则将实际 输入功率作为输出功率。
第二种情况，若实际输入功率大于或等于最大限定功率Pomax，则将最大限定功率作为输出功率。
其中，“功率优化器的实际输入功率Pin”和“光伏电池板的输出功率”是同一个概念。
通常，由于天气等多种因素的影响，导致光伏电池板的实际输出功率可能大于或小于功率优化器的最大限定功率Pomax，如果光伏电池板的输出功率大于或等于功率优化器的最大限定功率Pomax，则功率优化器的输出功率Po等于最大限定功率Pomax；如果光伏电池板的最大输出能力小于功率优化器的最大限定功率Pomax(比值小于1)，则功率优化器的输出功率Po等于光伏电池板的最大功率，可以通过功率优化器中的第一MPPT单元跟踪光伏电池板的最大功率。
在本实施例中，检测到后级光伏逆变器扰动后的母线电压，在第三电压段Vo2-Vo3内时(即功率优化器的输出电压在Vo2～Vo3之间时)，将功率优化器的“实际输入功率”与“最大限定功率Pomax”两者中的最小值，作为功率优化器的输出功率Po。
图6为本申请实施例提供的另一种光伏发电系统控制方法的流程示意图；可选地，如图6所示，在上述步骤303、根据实际输入功率以及预先生成的第一映射曲线，得到输出功率之后，还可以包括：
S601、根据最大功率点、及最大功率点对应的给定电压，确定第一给定电流。
其中，最大功率点是功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的。
需要说明的是，最大功率点单元也可以理解为是功率优化器中设置的第一MPPT单元，功率优化器的输入电压和输入电流，也即是光伏电池板产生的电压和电流。
图7为本申请实施例提供的一种光伏发电系统控制方法中功率优化器中MPPT单元与输出电压限功率环的工作原理示意图，如图7所示，第一MPPT单元对光伏电池板产生的电压和电流进行扰动，并追踪到光伏电池板的最大功率点，以及最大功率点对应的给定电压Vin*，将给定电压Vin*传输至输入电压内环，使得可以根据给定电压Vin*，确定第一给定电流I1*。
S602、根据输出功率、输出功率对应的输出电压，确定第二给定电流。
在本实施例中，根据功率优化器的输出功率Po与输出电压Uo的关系曲线图，得到输出电压Uo对应的输出功率Po，以及由输出电压限功率环路计算得到第二给定电流I2*。
S603、根据第一给定电流、第二给定电流，得到最小给定电流。
S604、使用最小给定电流，调节功率优化器的占空比。
在上述实施例的基础上，例如，将第一给定电流I1*、第二给定电流I2*进行比对，将 第一给定电流I1*、第二给定电流I2*中的最小值作为最小给定电流Imin*，并将最小给定电流Imin*传输至电流内环作为参考给定。
通常，功率优化器中还设置有MOSFET，因此，电流环路控制器可以使用最小给定电流，实现对MOSFET的占空比D的改变，进而产生了电流的扰动，达到稳定输出电压的目的。
图8为本申请实施例提供的一种光伏发电系统控制方法的整体流程示意图；可选地，如图7所示，该方法可以包括：
S801、获取功率优化器的输入电流和输入电压。
S802、根据输入电压和输入电流，得到实际输入功率。
S803、分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到第一映射曲线。
S804、若检测到后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
S805、若检测到后级光伏逆变器扰动后的母线电压，在第三电压段内时，则将功率优化器的实际输入功率和最大限定功率中的最小值作为输出功率。
可选地，该光伏发电系统控制方法的整体流程的具体实现步骤以及产生的有益效果已在前面具体实施例中进行了详细说明，此处不再一一赘述。
图9为本申请实施例提供的一种光伏发电系统控制装置的结构示意图；如图9所示，该光伏发电系统控制装置可以包括：获取模块901、处理模块902、确定模块903。
获取模块901，可以配置成用于获取功率优化器的输入电流和输入电压；
处理模块902，可以配置成用于根据输入电压和输入电流，得到实际输入功率；根据实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，第一映射曲线可以用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线可以包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，第二电压段对应的电压可以高于第一电压段对应的电压；
确定模块903，可以配置成用于将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器根据母线电压，确定目标最大功率。
可选地，第一映射曲线还可以包括：第三电压段恒定功率段，其中，第三电压段对应的电压可以高于第一电压段对应的电压，且可以低于第二电压段对应的电压；
第一电压段线性功率曲线可以为功率随电压升高而升高的线性曲线，第二电压段线性功率曲线可以为功率随电压升高而降低的线性曲线。
可选地，处理模块902，还可以配置成用于：
若检测到后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则可以根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
可选地，处理模块902，还可以配置成用于：
若检测到后级光伏逆变器扰动后的母线电压，在第三电压段内时，则可以根据第三电压段恒定功率段，得到输出功率。
可选地，处理模块902，还可以配置成用于：
若实际输入功率小于或等于功率优化器的最大限定功率，则将实际输入功率作为输出功率。
可选地，处理模块902，还可以配置成用于：
若实际输入功率大于最大限定功率，则将最大限定功率作为输出功率。
可选地，该装置还可以包括：调整模块；
调整模块，可以配置成用于分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到第一映射曲线。
可选地，调整模块，还可以配置成用于：
将第一电压段与输出功率的对应关系调整为功率随电压升高而升高的线性关系；
将第二电压段与输出功率的对应关系调整为功率随电压升高而降低的线性关系。
可选地，处理模块902，还可以配置成用于：
根据最大功率点、及最大功率点对应的给定电压，确定第一给定电流；其中，最大功率点是功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的；根据输出功率、输出功率对应的输出电压，确定第二给定电流；根据第一给定电流、第二给定电流，得到最小给定电流；
该装置还可以包括：调节模块，可以配置成用于使用最小给定电流，调节功率优化器的占空比。
上述装置用于执行前述实施例提供的方法，其实现原理和技术效果类似，在此不再赘述。
以上这些模块可以是被配置成实施以上方法的一个或多个集成电路，例如：一个或多个特定集成电路(Application Specific Integrated Circuit，简称ASIC)，或，一个或多个微处理器(digital singnal processor，简称DSP)，或，一个或者多个现场可编程门阵列(Field Programmable Gate Array，简称FPGA)等。再如，当以上某个模块通过处理元件调度程序代码的形式实现时，该处理元件可以是通用处理器，例如中央处理器(Central Processing Unit，简称CPU)或其它可以调用程序代码的处理器。再如，这些模块可以集成在一起，以片上系统(system-on-a-chip，简称SOC)的形式实现。
可选地，本申请还提供一种程序产品，例如计算机可读存储介质，可以包括程序，该程序在被处理器执行时用于执行上述方法实施例。
在本申请所提供的几个实施例中，应该理解到，所揭露的装置和方法，可以通过其它的方式实现。例如，以上所描述的装置实施例仅仅是示意性的，例如，所述单元的划分，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，装置或单元的间接耦合或通信连接，可以是电性，机械或其它的形式。
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。
另外，在本申请各个实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。上述集成的单元既可以采用硬件的形式实现，也可以采用硬件加软件功能单元的形式实现。
上述以软件功能单元的形式实现的集成的单元，可以存储在一个计算机可读取存储介质中。上述软件功能单元存储在一个存储介质中，包括若干指令用以使得一台计算机设备(可以是个人计算机，服务器，或者网络设备等)或处理器(英文：processor)执行本申请各个实施例所述方法的部分步骤。而前述的存储介质包括：U盘、移动硬盘、只读存储器(英文：Read-Only Memory，简称：ROM)、随机存取存储器(英文：Random Access Memory，简称：RAM)、磁碟或者光盘等各种可以存储程序代码的介质。
工业实用性
本申请提供了一种光伏发电系统控制方法、装置、功率优化器及存储介质。该方法包括：获取功率优化器的输入电流和输入电压；根据输入电压和输入电流，得到实际输入功率；根据实际输入功率以及预先生成的第一映射曲线，得到输出功率；第一映射曲线用于指示功率优化器的输出电压与输出功率的对应关系，第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，第二电压段对应的电压高于第一电压段对应的电压；将输出功率对应的母线电压输出至后级光伏逆变器，以使得后级光伏逆变器根据母线电压，确定目标最大功率。本方案，能够有效平衡功率优化器和光伏逆变器之间的竞争关系，避免出现失配震荡的情况。
此外，可以理解的是，本申请的光伏发电系统控制方法、装置、功率优化器及存储介质是可以重现的，并且可以用在多种工业应用中。例如，本申请的光伏发电系统控制方法、装置、功率优化器及存储介质可以用于电力电子的技术领域。

Claims (20)

  1. 一种光伏发电系统控制方法，其特征在于，应用于光伏发电系统中的功率优化器，所述方法包括：
    获取功率优化器的输入电流和输入电压；
    根据所述输入电压和所述输入电流，得到实际输入功率；
    根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，所述第一映射曲线用于指示所述功率优化器的输出电压与输出功率的对应关系，所述第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，所述第二电压段对应的电压高于所述第一电压段对应的电压；
    将所述输出功率对应的母线电压输出至后级光伏逆变器，以使得所述后级光伏逆变器根据所述母线电压，确定目标最大功率。
  2. 根据权利要求1所述的方法，其特征在于，所述第一映射曲线还包括：第三电压段恒定功率段，其中，所述第三电压段对应的电压高于所述第一电压段对应的电压，且低于所述第二电压段对应的电压；
    所述第一电压段线性功率曲线为功率随电压升高而升高或功率随电压降低而降低的线性曲线，所述第二电压段线性功率曲线为功率随电压升高而降低或功率随电压降低而升高的线性曲线。
  3. 根据权利要求2所述的方法，其特征在于，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率，包括：
    若检测到所述后级光伏逆变器扰动后的母线电压，在第一电压段或第二电压段内时，则根据第一电压段线性功率曲线或第二电压段线性功率曲线，得到输出功率。
  4. 根据权利要求3所述的方法，其特征在于，还包括：
    若检测到所述后级光伏逆变器扰动后的母线电压，在第三电压段内时，则根据第三电压段恒定功率段，得到输出功率。
  5. 根据权利要求4所述的方法，其特征在于，所述根据第三电压段恒定功率段，得到输出功率，包括：
    若所述实际输入功率小于或等于所述功率优化器的最大限定功率，则将所述实际输入功率作为输出功率。
  6. 根据权利要求5所述的方法，其特征在于，还包括：
    若所述实际输入功率大于所述最大限定功率，则将所述最大限定功率作为输出功率。
  7. 根据权利要求1至6中任一项所述的方法，其特征在于，所述根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率之前，还包括：
    分别对第一电压段、第二电压段与输出功率的对应关系进行调整，得到所述第一映射曲线。
  8. 根据权利要求7所述的方法，其特征在于，所述分别对所述第一电压段、所述第二电压段与所述输出功率的对应关系进行调整，包括：
    将所述第一电压段与所述输出功率的对应关系调整为功率随电压升高而升高的线性关系；
    将所述第二电压段与所述输出功率的对应关系调整为功率随电压升高而降低的线性关系。
  9. 根据权利要求1至8中的任一项所述的方法，其特征在于，所述方法还包括：在根据所述实际输入功率以及预先生成的第一映射曲线得到输出功率之后，
    根据最大功率点、及所述最大功率点对应的给定电压，确定第一给定电流；其中，所述最大功率点是所述功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的；
    根据所述输出功率、所述输出功率对应的输出电压，确定第二给定电流；
    根据所述第一给定电流、所述第二给定电流，得到最小给定电流；
    使用所述最小给定电流，调节所述功率优化器的占空比。
  10. 一种光伏发电系统控制装置，其特征在于，所述光伏发电系统控制装置包括：获取模块、处理模块、确定模块；
    所述获取模块，配置成用于获取功率优化器的输入电流和输入电压；
    所述处理模块，配置成用于根据所述输入电压和所述输入电流，得到实际输入功率；根据所述实际输入功率以及预先生成的第一映射曲线，得到输出功率；其中，所述第一映射曲线用于指示所述功率优化器的输出电压与输出功率的对应关系，所述第一映射曲线包括：第一电压段线性功率曲线和第二电压段线性功率曲线，其中，所述第二电压段对应的电压高于所述第一电压段对应的电压；
    所述确定模块，配置成用于将所述输出功率对应的母线电压输出至后级光伏逆变器，以使得所述后级光伏逆变器根据所述母线电压，确定目标最大功率。
  11. 根据权利要求10所述的光伏发电系统控制装置，其特征在于，所述第一映射曲线还包括第三电压段恒定功率段，其中，所述第三电压段对应的电压高于所述第一电压段对应的电压，且低于所述第二电压段对应的电压；
    所述第一电压段线性功率曲线可以为功率随电压升高而升高或功率随电压降低而降低的线性曲线，所述第二电压段线性功率曲线可以为功率随电压升高而降低或功率随电压降低而升高的线性曲线。
  12. 根据权利要求11所述的光伏发电系统控制装置，其特征在于，所述处理模块还配置成用于：若检测到所述后级光伏逆变器扰动后的所述母线电压，在所述第一电压段或所述第二电压段内时，则根据所述第一电压段线性功率曲线或所述第二电压段线性功率曲线，得到输出功率。
  13. 根据权利要求12所述的光伏发电系统控制装置，其特征在于，所述处理模块还配置成用于：
    若检测到所述后级光伏逆变器扰动后的所述母线电压，在所述第三电压段内时，则根据所述第三电压段恒定功率段，得到输出功率。
  14. 根据权利要求13所述的光伏发电系统控制装置，其特征在于，所述处理模块还配置成用于：若所述实际输入功率小于或等于所述功率优化器的最大限定功率，则将所述实际输入功率作为输出功率。
  15. 根据权利要求14所述的光伏发电系统控制装置，其特征在于，所述处理模块还配置成用于：
    若所述实际输入功率大于所述最大限定功率，则将所述最大限定功率作为输出功率。
  16. 根据权利要求10至15中任一项所述的光伏发电系统控制装置，其特征在于，所述光伏发电系统控制装置还包括调整模块，其中，所述调整模块配置成用于分别对所述第一电压段、所述第二电压段与输出功率的对应关系进行调整，得到所述第一映射曲线。
  17. 根据权利要求16所述的光伏发电系统控制装置，其特征在于，所述调整模块还配置成用于：
    将所述第一电压段与输出功率的对应关系调整为功率随电压升高而升高的线性关系；
    将所述第二电压段与输出功率的对应关系调整为功率随电压升高而降低的线性关系。
  18. 根据权利要求10至17中的任一项所述的光伏发电系统控制装置，其特征在于，所述光伏发电系统控制装置还包括调节模块，
    其中，所述处理模块还配置成用于：根据最大功率点、及所述最大功率点对应的给定电压，确定第一给定电流；其中，所述最大功率点是所述功率优化器中的最大功率点单元，根据输入电压和输入电流进行扰动得到的；根据所述输出功率、所述输出功率对应的输出电压，确定第二给定电流；根据所述第一给定电流、所述第二给定电流，得到最小给定电流；以及
    所述调节模块配置成用于使用所述最小给定电流，调节所述功率优化器的占空比。
  19. 一种功率优化器，其特征在于，所述功率优化器包括：处理器、存储介质和总线，所述存储介质存储有所述处理器可执行的机器可读指令，当功率优化器运行时，所述处理器与所述存储介质之间通过总线通信，所述处理器执行所述机器可读指令，以执行根据权 利要求1至9中的任一所述的方法的步骤。
  20. 一种计算机可读存储介质，其特征在于，所述存储介质上存储有计算机程序，所述计算机程序被处理器运行时执行根据权利要求1至9中的任一所述的方法的步骤。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107154780A (zh) * 2017-06-08 2017-09-12 阳光电源股份有限公司 一种光伏发电系统及其功率控制方法与功率优化器
CN109254616A (zh) * 2018-10-10 2019-01-22 阳光电源股份有限公司 一种输入功率控制方法以及光伏逆变器
CN109713714A (zh) * 2018-11-15 2019-05-03 华为技术有限公司 一种最大功率点跟踪方法及设备
CN109787289A (zh) * 2019-03-15 2019-05-21 矽力杰半导体技术(杭州)有限公司 功率变换系统、光伏优化器及功率跟踪方法
CN113452071A (zh) * 2021-06-25 2021-09-28 江苏领充创享新能源科技有限公司 光伏发电系统控制方法、装置、功率优化器及存储介质

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107154780A (zh) * 2017-06-08 2017-09-12 阳光电源股份有限公司 一种光伏发电系统及其功率控制方法与功率优化器
CN109254616A (zh) * 2018-10-10 2019-01-22 阳光电源股份有限公司 一种输入功率控制方法以及光伏逆变器
CN109713714A (zh) * 2018-11-15 2019-05-03 华为技术有限公司 一种最大功率点跟踪方法及设备
CN109787289A (zh) * 2019-03-15 2019-05-21 矽力杰半导体技术(杭州)有限公司 功率变换系统、光伏优化器及功率跟踪方法
CN113452071A (zh) * 2021-06-25 2021-09-28 江苏领充创享新能源科技有限公司 光伏发电系统控制方法、装置、功率优化器及存储介质

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