CN116937731A - Off-grid photovoltaic system control method, device, equipment and storage medium - Google Patents
Off-grid photovoltaic system control method, device, equipment and storage medium Download PDFInfo
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- CN116937731A CN116937731A CN202310718261.6A CN202310718261A CN116937731A CN 116937731 A CN116937731 A CN 116937731A CN 202310718261 A CN202310718261 A CN 202310718261A CN 116937731 A CN116937731 A CN 116937731A
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- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000004146 energy storage Methods 0.000 claims abstract description 54
- 238000004590 computer program Methods 0.000 claims description 6
- 230000006872 improvement Effects 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000013082 photovoltaic technology Methods 0.000 description 1
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
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Classifications
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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
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
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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
- H02J3/388—Islanding, i.e. disconnection of local power supply from the network
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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
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02S—GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES
- H02S40/00—Components or accessories in combination with PV modules, not provided for in groups H02S10/00 - H02S30/00
- H02S40/30—Electrical components
- H02S40/32—Electrical components comprising DC/AC inverter means associated with the PV module itself, e.g. AC modules
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- 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
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a control method, a device, equipment and a storage medium of an off-grid photovoltaic system, wherein the control method comprises the following steps: obtaining the maximum battery charging power Pbat_charge_max of the energy storage battery module; freq_target=freq_end_limit of the photovoltaic inverter when pbat_charge_max=0; reducing the freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not greater than Pbat_charge_max-Poffset; when pbat_charge_max +.0 and pbat_charge_real > pbat_charge_max, the freq_target of the photovoltaic inverter is increased. The method can protect the energy storage battery module.
Description
Technical Field
The present invention relates to the field of photovoltaic technologies, and in particular, to a method, an apparatus, a device, and a storage medium for controlling an off-grid photovoltaic system.
Background
In the photovoltaic system, the photovoltaic module can convert solar energy into electric energy, and after the treatment of the photovoltaic inverter, alternating current with the mains frequency can be obtained, so that the alternating current can be supplied to a power transmission network, and the alternating current can be finally stored in an energy storage battery after the treatment of the photovoltaic inverter.
In the prior art, the photovoltaic inverter is not generally controlled effectively, and the electric energy generated by the photovoltaic module is processed by the photovoltaic inverter. It will be appreciated that if the photovoltaic system is not connected to the grid (i.e. off-grid), all of the electrical energy output by the photovoltaic inverter is used to charge the energy storage battery, and sometimes, excessive electrical energy is inverted by the inverter, which can cause damage to the battery.
Disclosure of Invention
In view of the above, the main objective of the present invention is to provide a control method, apparatus, device and storage medium for off-grid photovoltaic system.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows: an off-grid photovoltaic system control method, the off-grid photovoltaic system comprising: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter; the method comprises the following steps: obtaining the maximum battery charging power Pbat_charge_max of the energy storage battery module; when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, wherein freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power regulation allowable deviation value of the photovoltaic inverter; when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, reducing Freq_target of the photovoltaic inverter, wherein Pbat_charge_real is battery real-time charging power of the energy storage battery module, and Poffset is a power regulation allowable deviation value of the photovoltaic inverter; when pbat_charge_max +.0, and pbat_charge_real > pbat_charge_max, the freq_target of the photovoltaic inverter is increased.
As an improvement of the embodiment of the present invention, the "reducing freq_target of the photovoltaic inverter" specifically includes: when freq_target > = freq_start_limit+freq_step, freq_target=freq_target- (freq_target-freq_start_limit)/step_adjust of the photovoltaic inverter, wherein freq_start_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, frequency adjustment Step, and Step width adjuster, respectively.
As an improvement of the embodiment of the present invention, the "reducing freq_target of the photovoltaic inverter" specifically includes: when freq_start_limit is less than or equal to freq_target < freq_start_limit+freq_step, freq_target=freq_target-freq_min_adjust of the photovoltaic inverter, wherein freq_start_limit and freq_step are respectively the derating start frequency point of the photovoltaic inverter, freq_min_adjust is constant and freq_min_adjust >0.
As an improvement of the embodiment of the present invention, the "reducing freq_target of the photovoltaic inverter" specifically includes: when freq_target < freq_start_limit, freq_target=0 of the photovoltaic inverter, wherein freq_start_limit is the derating start frequency point of the photovoltaic inverter.
As an improvement of the embodiment of the present invention, the "increasing freq_target of the photovoltaic inverter" specifically includes: when freq_target > freq_end_limit-freq_step, freq_target=freq_target+freq_min_adjust of the photovoltaic inverter, wherein freq_end_limit, freq_step and freq_min_adjust are the derated cutoff frequency point, the frequency adjustment step size and the frequency minimum adjustment value of the photovoltaic inverter, respectively.
As an improvement of the embodiment of the present invention, the "increasing freq_target of the photovoltaic inverter" specifically includes: when freq_start_limit is less than or equal to freq_target is less than or equal to freq_end_limit-freq_step, freq_target=freq_target+ = (freq_end_limit-freq_target)/step_adjust, freq_start_limit, freq_end_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, frequency adjustment Step, and Step width adjuster, respectively.
As an improvement of the embodiment of the present invention, the "increasing freq_target of the photovoltaic inverter" specifically includes: when freq_target is less than or equal to freq_end_limit-freq_step and freq_target < freq_start_limit, freq_target=freq_start_limit of the photovoltaic inverter, wherein freq_start_limit, freq_end_limit, and freq_step are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, and frequency adjustment step, respectively.
The embodiment of the invention also provides a control device of the off-grid photovoltaic system, which comprises: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter; the method comprises the following modules: the information acquisition module is used for acquiring the maximum battery charging power Pbat_charge_max of the energy storage battery module; a first processing module, configured to, when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, where freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power adjustment allowable deviation value of the photovoltaic inverter; the second processing module is used for reducing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, wherein Pbat_charge_real is the battery real-time charging power of the energy storage battery module, and Poffset is the power regulation allowable deviation value of the photovoltaic inverter; and the third processing module is used for increasing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real > Pbat_charge_max.
The embodiment of the invention also provides equipment, which comprises: one or more processors; a storage means for storing one or more programs; the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the method as described in any of the preceding claims.
The embodiment of the invention also provides a storage medium, wherein the storage medium stores a computer program, and the computer program realizes the method when being executed by a processor.
The control method, the device, the equipment and the storage medium of the off-grid photovoltaic system provided by the embodiment of the invention have the following advantages: the embodiment of the invention discloses a control method, a device, equipment and a storage medium of an off-grid photovoltaic system, wherein the control method comprises the following steps: obtaining the maximum battery charging power Pbat_charge_max of the energy storage battery module; freq_target=freq_end_limit of the photovoltaic inverter when pbat_charge_max=0; reducing freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset; when pbat_charge_max +.0, and pbat_charge_real > pbat_charge_max, the freq_target of the photovoltaic inverter is increased. The method can protect the energy storage battery module.
Drawings
Fig. 1 is a schematic structural diagram of an off-grid photovoltaic system in an embodiment;
fig. 2 is a schematic diagram of a control method of an off-grid photovoltaic system in an embodiment;
fig. 3 is a flow chart of a control method of the off-grid photovoltaic system in the embodiment.
Detailed Description
The present invention will be described in detail below with reference to embodiments shown in the drawings. The embodiment is not intended to limit the present invention, and structural, methodological, or functional modifications of the invention according to the embodiment are included in the scope of the invention.
The following description and the drawings sufficiently illustrate specific embodiments herein to enable those skilled in the art to practice them. Portions and features of some embodiments may be included in, or substituted for, those of others. The scope of the embodiments herein includes the full scope of the claims, as well as all available equivalents of the claims. The terms "first," "second," and the like herein are used merely to distinguish one element from another element and do not require or imply any actual relationship or order between the elements. Indeed the first element could also be termed a second element and vice versa. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such structure, apparatus, or device. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a structure, apparatus or device comprising the element. Various embodiments are described herein in a progressive manner, each embodiment focusing on differences from other embodiments, and identical and similar parts between the various embodiments are sufficient to be seen with each other.
The terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like herein refer to an orientation or positional relationship based on that shown in the drawings, merely for ease of description herein and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus are not to be construed as limiting the invention. In the description herein, unless otherwise specified and limited, the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, mechanically or electrically coupled, may be in communication with each other within two elements, may be directly coupled, or may be indirectly coupled through an intermediary, as would be apparent to one of ordinary skill in the art.
The first embodiment of the invention provides a control method of an off-grid photovoltaic system, which comprises the following steps: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter;
here, an execution device may be provided in the off-grid photovoltaic system, the execution device executing the control method.
Here, a photovoltaic module is a power generation device that generates direct current when exposed to sunlight, and can be generally divided into: monocrystalline silicon solar panels, polycrystalline silicon solar panels, amorphous silicon solar panels, and multi-compound solar panels. The photovoltaic inverter can control the charging and discharging processes of the energy storage battery and perform alternating current-direct current conversion. In addition, the off-grid photovoltaic system can further comprise a photovoltaic inverter, and the photovoltaic inverter can convert variable direct current voltage generated by the photovoltaic assembly into an inverter with mains frequency alternating current and can be used by off-grid electrical appliances (namely, delivered to an energy storage battery for storage or used by a load).
Here, fig. 2 shows a PF curve of a photovoltaic inverter, where f0 is typically 50Hz (60 Hz in some countries), limit Pac is the power percentage, and the base is the last pack of power samples of the photovoltaic inverter before triggering the power limitation or the rated power value of the photovoltaic inverter. The derate Start frequency point freq_start_limit and the derate cutoff frequency point freq_end_limit correspond to Fac-Start delta and Fac-Limit delta, respectively, in fig. 2.
As shown in FIG. 1, comprises the following steps
Step 301: obtaining the maximum battery charging power Pbat_charge_max of the energy storage battery module;
step 302: when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, wherein freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power regulation allowable deviation value of the photovoltaic inverter; when pbat_charge_max=0, the energy storage battery module can be considered to be fully charged, and in addition, as can be seen from the PF curve relationship in fig. 2, when the frequency reaches the derating cut-off frequency point, the power is reduced to 0. When the energy storage converter runs off the grid, the power of the alternating current side (namely, the side electrically connected to the photovoltaic inverter) cannot be controlled, and the energy storage battery module is fully charged and needs to be protected against overvoltage, so that the power of the photovoltaic inverter connected to the alternating current side of the energy storage converter needs to be reduced to 0 at the moment, and the overcharge of the battery is further indirectly avoided.
Step 303: when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, reducing Freq_target of the photovoltaic inverter, wherein Pbat_charge_real is battery real-time charging power of the energy storage battery module, and Poffset is a power regulation allowable deviation value of the photovoltaic inverter;
step 304: when pbat_charge_max +.0, and pbat_charge_real > pbat_charge_max, the freq_target of the photovoltaic inverter is increased.
When pbat_charge_max is not equal to 0, it can be considered that the energy storage battery module is not fully charged yet, and it is necessary to determine whether the actual charging of the energy storage battery module reaches the maximum chargeable power, if not, the down-conversion regulation is performed. If so, up-conversion regulation is performed.
From the PF curve relationship, frequency and power are inversely proportional. In addition, considering the real-time power fluctuation condition and the load change condition of the energy storage battery module under the constant working condition, when judging whether the actual charging of the energy storage battery module reaches the maximum chargeable state, adding a dead zone width (Poffset) to avoid frequent adjustment at critical points of full charge and less than full charge.
In this embodiment, the "reducing freq_target of the photovoltaic inverter" specifically includes:
when freq_target > = freq_start_limit+freq_step, freq_target=freq_target- (freq_target-freq_start_limit)/step_adjust of the photovoltaic inverter, wherein freq_start_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, frequency adjustment Step, and Step width adjuster, respectively. The off-grid frequency control precision of the energy storage converter, the frequency change response sensitivity of the photovoltaic inverter and the adjustment speed are considered, a Step width adjuster (step_adjust) is added, the frequency amplitude of each beat of adjustment is ensured to be effective and reasonable, the adjustment speed is reduced when the target value is trended, and frequent oscillation is avoided.
In this embodiment, the "reducing freq_target of the photovoltaic inverter" specifically includes:
when freq_start_limit is less than or equal to freq_target < freq_start_limit+freq_step, freq_target=freq_target-freq_min_adjust of the photovoltaic inverter, wherein freq_start_limit and freq_step are respectively the derating start frequency point of the photovoltaic inverter, freq_min_adjust is constant and freq_min_adjust >0. Here, because of the presence of the step width regulator, there is a dead zone at the end of the regulation, when entering the dead zone, the regulation is performed with a frequency minimum regulation value (freq_min_adjust), which also needs to be determined according to the off-grid frequency control accuracy of the energy storage converter and the frequency variation response sensitivity and regulation speed of the photovoltaic inverter.
In this embodiment, the "reducing freq_target of the photovoltaic inverter" specifically includes:
when freq_target < freq_start_limit, freq_target=0 of the photovoltaic inverter, wherein freq_start_limit is the derating start frequency point of the photovoltaic inverter.
In this embodiment, the "increasing freq_target of the photovoltaic inverter" specifically includes:
when freq_target > freq_end_limit-freq_step, freq_target=freq_target+freq_min_adjust of the photovoltaic inverter, wherein freq_end_limit, freq_step and freq_min_adjust are the derated cutoff frequency point, the frequency adjustment step size and the frequency minimum adjustment value of the photovoltaic inverter, respectively.
In this embodiment, the "increasing freq_target of the photovoltaic inverter" specifically includes:
when freq_start_limit is less than or equal to freq_target is less than or equal to freq_end_limit-freq_step, freq_target=freq_target+ = (freq_end_limit-freq_target)/step_adjust, freq_start_limit, freq_end_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, frequency adjustment Step, and Step width adjuster, respectively.
In this embodiment, the "increasing freq_target of the photovoltaic inverter" specifically includes:
when freq_target is less than or equal to freq_end_limit-freq_step and freq_target < freq_start_limit, freq_target=freq_start_limit of the photovoltaic inverter, wherein freq_start_limit, freq_end_limit, and freq_step are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, and frequency adjustment step, respectively.
The second embodiment of the invention provides a control device of an off-grid photovoltaic system, which comprises: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter; the method comprises the following modules:
the information acquisition module is used for acquiring the maximum battery charging power Pbat_charge_max of the energy storage battery module;
a first processing module, configured to, when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, where freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power adjustment allowable deviation value of the photovoltaic inverter;
the second processing module is used for reducing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, wherein Pbat_charge_real is the battery real-time charging power of the energy storage battery module, and Poffset is the power regulation allowable deviation value of the photovoltaic inverter;
and the third processing module is used for increasing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real > Pbat_charge_max.
An embodiment of the present invention provides an apparatus, including: one or more processors; a storage means for storing one or more programs; the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the method of embodiment one.
A fourth embodiment of the present invention provides a storage medium storing a computer program that when executed by a processor implements the method in the embodiment.
It should be noted that, although the steps are described above in a specific order, it is not meant to necessarily be performed in the specific order, and in fact, some of the steps may be performed concurrently or even in a changed order, as long as the required functions are achieved.
The present invention may be a system, method, and/or computer program product. The computer program product may include a readable storage medium having computer readable program instructions embodied thereon for causing a processor to implement aspects of the present invention.
The readable storage medium may be a tangible device that retains and stores instructions for use by an instruction execution device. The readable storage medium may include, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: portable computer disks, hard disks, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static Random Access Memory (SRAM), portable compact disk read-only memory (CD-ROM), digital Versatile Disks (DVD), memory sticks, floppy disks, mechanical coding devices, punch cards or in-groove structures such as punch cards or grooves having instructions stored thereon, and any suitable combination of the foregoing.
The foregoing description of embodiments of the invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the technical improvements in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
Claims (10)
1. An off-grid photovoltaic system control method, the off-grid photovoltaic system comprising: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter; the method is characterized by comprising the following steps of:
obtaining the maximum battery charging power Pbat_charge_max of the energy storage battery module;
when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, wherein freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power regulation allowable deviation value of the photovoltaic inverter;
when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, reducing Freq_target of the photovoltaic inverter, wherein Pbat_charge_real is battery real-time charging power of the energy storage battery module, and Poffset is a power regulation allowable deviation value of the photovoltaic inverter;
when pbat_charge_max +.0, and pbat_charge_real > pbat_charge_max, the freq_target of the photovoltaic inverter is increased.
2. The control method according to claim 1, wherein the reducing freq_target of the photovoltaic inverter specifically comprises:
when freq_target > = freq_start_limit+freq_step, freq_target=freq_target- (freq_target-freq_start_limit)/step_adjust of the photovoltaic inverter, wherein freq_start_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, frequency adjustment Step, and Step width adjuster, respectively.
3. The control method according to claim 1, wherein the reducing freq_target of the photovoltaic inverter specifically comprises:
when freq_start_limit is less than or equal to freq_target < freq_start_limit+freq_step, freq_target=freq_target-freq_min_adjust of the photovoltaic inverter, wherein freq_start_limit and freq_step are respectively the derating start frequency point of the photovoltaic inverter, freq_min_adjust is constant and freq_min_adjust >0.
4. The control method according to claim 1, wherein the reducing freq_target of the photovoltaic inverter specifically comprises:
when freq_target < freq_start_limit, freq_target=0 of the photovoltaic inverter, wherein freq_start_limit is the derating start frequency point of the photovoltaic inverter.
5. The control method according to claim 1, wherein the increasing freq_target of the photovoltaic inverter specifically comprises:
when freq_target > freq_end_limit-freq_step, freq_target=freq_target+freq_min_adjust of the photovoltaic inverter, wherein freq_end_limit, freq_step and freq_min_adjust are the derated cutoff frequency point, the frequency adjustment step size and the frequency minimum adjustment value of the photovoltaic inverter, respectively.
6. The control method according to claim 1, wherein the increasing freq_target of the photovoltaic inverter specifically comprises:
when freq_start_limit is less than or equal to freq_target is less than or equal to freq_end_limit-freq_step, freq_target=freq_target+ = (freq_end_limit-freq_target)/step_adjust, freq_start_limit, freq_end_limit, freq_step, and step_adjust are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, frequency adjustment Step, and Step width adjuster, respectively.
7. The control method according to claim 1, wherein the increasing freq_target of the photovoltaic inverter specifically comprises:
when freq_target is less than or equal to freq_end_limit-freq_step and freq_target < freq_start_limit, freq_target=freq_start_limit of the photovoltaic inverter, wherein freq_start_limit, freq_end_limit, and freq_step are the photovoltaic inverter derating start frequency point, derating cutoff frequency point, and frequency adjustment step, respectively.
8. A control device of an off-grid photovoltaic system, the off-grid photovoltaic system comprising: the photovoltaic module, the photovoltaic inverter, the energy storage converter and the energy storage battery module are electrically connected with the photovoltaic inverter, and the energy storage battery module is electrically connected to the energy storage converter; the device is characterized by comprising the following modules:
the information acquisition module is used for acquiring the maximum battery charging power Pbat_charge_max of the energy storage battery module;
a first processing module, configured to, when pbat_charge_max=0, freq_target=freq_end_limit of the photovoltaic inverter, where freq_end_limit is a derated cutoff frequency point of the photovoltaic inverter, and freq_target is a power adjustment allowable deviation value of the photovoltaic inverter;
the second processing module is used for reducing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real is not more than Pbat_charge_max-Poffset, wherein Pbat_charge_real is the battery real-time charging power of the energy storage battery module, and Poffset is the power regulation allowable deviation value of the photovoltaic inverter;
and the third processing module is used for increasing the Freq_target of the photovoltaic inverter when Pbat_charge_max is not equal to 0 and Pbat_charge_real > Pbat_charge_max.
9. An apparatus, comprising:
one or more processors;
a storage means for storing one or more programs;
when executed by the one or more processors, causes the one or more processors to implement the method of any of claims 1-7.
10. A storage medium storing a computer program which, when executed by a processor, implements the method of any one of claims 1-7.
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| CN117639081A (en) * | 2024-01-23 | 2024-03-01 | 深圳市德兰明海新能源股份有限公司 | Photovoltaic energy storage inversion parallel operation system and photovoltaic energy scheduling method thereof |
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| CN117639081A (en) * | 2024-01-23 | 2024-03-01 | 深圳市德兰明海新能源股份有限公司 | Photovoltaic energy storage inversion parallel operation system and photovoltaic energy scheduling method thereof |
| CN117639081B (en) * | 2024-01-23 | 2024-04-30 | 深圳市德兰明海新能源股份有限公司 | Photovoltaic energy storage inversion parallel operation system and photovoltaic energy scheduling method thereof |
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