CN113690946B - Photovoltaic grid-connected system and method based on synchronous motor dynamic response sampling - Google Patents
Photovoltaic grid-connected system and method based on synchronous motor dynamic response sampling Download PDFInfo
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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
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
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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
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
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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
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
- H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
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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
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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
- 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
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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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- 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
- Y02E70/00—Other energy conversion or management systems reducing GHG emissions
- Y02E70/30—Systems combining energy storage with energy generation of non-fossil origin
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Abstract
The invention provides a photovoltaic grid-connected system and a method based on synchronous motor dynamic response sampling, which relate to the technical field of power systems and comprise a photovoltaic battery, an energy storage unit, a power distributor, a first direct current/direct current converter, a second direct current/direct current converter, a third direct current/direct current converter, a direct current/alternating current converter, a direct current motor and an alternating current generator; the photovoltaic cell is connected with the power divider, and the power divider is connected with the power divider through the first direct current/direct current converter; the power divider is connected with the second direct current/direct current converter and supplies power to the direct current motor; an output shaft of the direct current motor drives the alternating current motor to generate electricity, and the electric energy of the alternating current generator is merged into a power grid; the power divider is connected with the DC/AC converter through a third DC/DC converter, and the output side of the DC/AC converter is connected with an external power grid. The invention can provide real inertia and reactive support for the power grid, thereby improving the operation stability of the system.
Description
Technical Field
The invention relates to the technical field of energy-saving energy storage point power grids, in particular to a photovoltaic grid-connected system and method based on synchronous motor dynamic response sampling.
Background
Under the promotion of energy transformation and technological progress, high-permeability renewable energy and high-proportion power electronic equipment become important trends and key characteristics of power system development, the dynamic characteristics of the power system are changed deeply, and a series of system stability problems generated therewith need to be solved urgently. Photovoltaic is one of main new energy power generation forms, with continuous emergence of photovoltaic manufacturing and grid-connected power generation technical innovation, the cost of photovoltaic products is continuously reduced, the grid-connected proportion of photovoltaic power generation is continuously improved in the future, the influence effect of photovoltaic grid connection on an electric power system is gradually shown, and the reason of generating adverse effect is as follows:
1) for a photovoltaic power station, the immunity of the photovoltaic is weak, the overload capacity is low due to the grid connection form of power electronic equipment, the tolerance capacity to frequency and voltage deviation is seriously insufficient compared with that of a synchronous unit, the grid disconnection is easy under the condition that the frequency or voltage of a system is greatly fluctuated, and the adverse effect is brought to the stability of the system;
) For a power system, power electronic equipment belongs to zero inertia or low inertia equipment, and large-scale photovoltaic grid connection through the power electronic equipment can cause the inertia and damping characteristics of the system to be greatly reduced, so that the system stability problem is more prominent. Although the control technology of the networking type converter represented by a virtual synchronous machine can simulate the external characteristics of frequency and voltage regulation of the synchronous machine to a certain extent, the electromagnetic transient characteristics of the ms-level time scale of the synchronous machine are difficult to simulate due to additional control delay, sampling links and the like;
) The problem that how to control the power angle of the system to realize stable grid-connected operation is the primary solution is that the system stability margin is obviously increased by adding the synchronous motor pair in the photovoltaic grid-connected link, but the difficulty lies in the coordination control between the synchronous motor pair and the photovoltaic power station. In addition, the realization of a multi-time scale control strategy considering photovoltaic output characteristics and system operation characteristics of a synchronous motor is also a difficulty in the application of the technology. As one of main new energy forms, with the further improvement of the grid-connected ratio of photovoltaic, the influence of photovoltaic on the stability of the voltage, the frequency and the like of the system will be further shown, and a friendly grid-connected system of a photovoltaic cluster needs to be developed urgently, and a corresponding control method is matched to provide positive effects for the stable operation of the system.
Disclosure of Invention
In view of the above, the present invention provides a photovoltaic grid-connected system and method based on synchronous motor dynamic response sampling, so as to significantly improve the photovoltaic grid-connected friendly property on the premise of not increasing control delay, and provide real inertia and reactive support for a power grid, thereby improving the operation stability of the system.
In one aspect, the invention provides a photovoltaic grid-connected system based on synchronous motor dynamic response sampling, which comprises:
the photovoltaic power generation system comprises a photovoltaic cell, an energy storage unit, a power divider, a first direct current/direct current converter, a second direct current/direct current converter, a third direct current/direct current converter, a direct current/alternating current converter, a direct current motor and an alternating current generator;
the photovoltaic cell is connected with the power divider, and the power divider is connected with the power divider through the first direct current/direct current converter;
the power divider is connected through the second direct current/direct current converter, and the second direct current/direct current converter supplies power to the direct current motor;
an output shaft of the direct current motor drives the alternating current generator to generate electricity, and the electric energy of the alternating current generator is merged into a power grid;
the power divider is connected with the DC/AC converter through the third DC/DC converter, and the output side of the DC/AC converter is connected with an external power grid.
Preferably, the first dc/dc converter voltage conversion ratio is 37V/48V, the second dc/dc converter voltage conversion ratio is 37V/380V, and the third dc/dc converter voltage conversion ratio is: 37V/380V, the transformation ratio of the DC/AC converter is as follows: 380V/10000V.
In another aspect, the invention provides a synchronous motor dynamic response sampling-based photovoltaic grid-connected control method for a synchronous motor dynamic response sampling-based photovoltaic grid-connected system according to the first aspect, which applies an upper computer,
acquiring the state of charge of the energy storage unit, the three-phase voltage of the port of the alternating-current generator, the illumination intensity, the three-phase current of the port of the alternating-current generator and the output limit power P of the photovoltaic cell0；
Based on the state of charge of the energy storage unit, the three-phase voltage at the port of the alternating-current generator, the illumination intensity, the three-phase current at the port of the alternating-current generator and the output limit power P of the photovoltaic cell0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Output power P of the AC generator1The size of (d);
if the output limit power P of the photovoltaic cell is0Greater than or equal to the output power P of the alternator1；
And acquiring the charge state of the energy storage unit, and judging whether the residual capacity of the energy storage unit is greater than the minimum value of the allowable residual capacity or not based on the charge state of the energy storage unit.
Preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the residual electric quantity of the energy storage unit is larger than the allowable residual electric quantity, judging the output limit power P of the photovoltaic cell0Output power P of the AC generator1Whether the difference is greater than PsSaid P issThe maximum charge and discharge power of the energy storage unit is represented;
if yes, the power divider performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ； k 2 =（P 0 -P 1 - P s ）∕P 0 ； k 3 =P s ∕P 0 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =P 1 ∕P 0 ；k 2 =0；k 3 =（P 0 -P 1 ）∕P 0 。
preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the residual capacity of the energy storage unit is less than or equal to the allowable residual capacity, the power distributor performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ；k 2 =（P 0 -P 1 ）∕P 0 ； k 3 =0；
k 1—— a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 —the power divider is distributed to the proportionality coefficient of the energy storage unit.
Preferably, the energy storage unit-based state of charge, the three-phase voltage at the port of the alternator, the illumination intensity and the alternatorPort three-phase current and photovoltaic cell output limit power P0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Output power P of the AC generator1The step of (a) further comprises;
if the output limit power P of the photovoltaic cell is0Less than the output power P of the alternator1And acquiring the charge state of the energy storage unit, and judging whether the residual capacity of the energy storage unit is greater than the minimum value of the allowable residual capacity or not based on the charge state of the energy storage unit.
Preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the ratio is larger than the preset value, the power divider performs power distribution according to the following proportionality coefficient:
k 3 =P 0 ∕P 1 ；k 2 =0；k 3 =（P 1 -P 0 ）∕P 1 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =0；k 2 =0；k 3 = 1；
k 1 —a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 -a proportionality factor assigned by said power divider to said energy storage unit.
Preferably, the setting of the output current value and the output voltage value of the dc/ac converter is as follows:
I՚abc= I abc k2∕k1;
I՚abc-three phase currents output by the dc/ac converter;
I abc-three phase current at the alternator port;
U՚abc= U abc ;
U՚abc——three-phase voltage output by the direct current/alternating current converter;
U abc-the three phase voltage at the alternator port;
k1-a proportionality factor of the power of the alternator into the grid;
k2-a proportionality factor of the power of the dc/ac converter into the grid.
The embodiment of the invention has the following beneficial effects: the invention provides a photovoltaic grid-connected system and a method based on synchronous motor dynamic response sampling, wherein the system comprises a photovoltaic battery, an energy storage unit, a power distributor, a first direct current/direct current converter, a second direct current/direct current converter, a third direct current/direct current converter, a direct current/alternating current converter, a direct current motor and an alternating current generator; the photovoltaic cell is connected with the power divider, and the power divider is connected with the power divider through the first direct current/direct current converter; the power divider is connected with the second direct current/direct current converter and supplies power to the direct current motor; an output shaft of the direct current motor drives the alternating current motor to generate electricity, and the electric energy of the alternating current generator is merged into a power grid; the power divider is connected with the DC/AC converter through a third DC/DC converter, and the output side of the DC/AC converter is connected with an external power grid. By the system and the method provided by the invention, the photovoltaic grid-connected friendly property can be obviously improved on the premise of not increasing the control delay, and real inertia and reactive support are provided for a power grid, so that the operation stability of the system is improved.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a structural diagram of a photovoltaic grid-connected system based on synchronous motor dynamic response sampling according to an embodiment of the present invention;
fig. 2 is a flowchart of a first photovoltaic grid-connected system method based on synchronous motor dynamic response sampling according to an embodiment of the present invention;
fig. 3 is a flowchart of a second photovoltaic grid-connected system method based on synchronous motor dynamic response sampling according to an embodiment of the present invention;
fig. 4 is a flowchart of a third photovoltaic grid-connected system method based on synchronous motor dynamic response sampling according to an embodiment of the present invention.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
At present, photovoltaic is one of main new energy power generation forms, with continuous emergence of photovoltaic manufacturing and grid-connected power generation technical innovation, the cost of photovoltaic products is continuously reduced, the grid-connected proportion of photovoltaic power generation is continuously improved in the future, and the influence effect of the photovoltaic grid-connected on an electric power system is gradually shown.
In order to facilitate understanding of the embodiment, a photovoltaic grid-connected system and a method based on synchronous motor dynamic response sampling disclosed by the embodiment of the invention are first described in detail.
The first embodiment is as follows:
the embodiment of the invention provides a photovoltaic grid-connected system based on synchronous motor dynamic response sampling, which comprises:
the photovoltaic power generation system comprises a photovoltaic cell, an energy storage unit, a power divider, a first direct current/direct current converter, a second direct current/direct current converter, a third direct current/direct current converter, a direct current/alternating current converter, a direct current motor and an alternating current generator;
the photovoltaic cell is connected with the power divider, and the power divider is connected with the power divider through the first direct current/direct current converter;
the power divider is connected through the second direct current/direct current converter, and the second direct current/direct current converter supplies power to the direct current motor;
an output shaft of the direct current motor drives the alternating current motor to generate electricity, and the electric energy of the alternating current generator is merged into a power grid;
the power divider is connected with the DC/AC converter through the third DC/DC converter, and the output side of the DC/AC converter is connected with an external power grid.
Furthermore, the photovoltaic cell is an energy output module, and the photovoltaic cell panel receives sunlight irradiation to generate low-voltage galvanic current to form energy output outwards;
the energy storage unit is an energy absorption/release module and absorbs or releases energy generated by low-voltage direct current according to a control strategy and a command;
the first DC/DC converter, the second DC/DC converter, the third DC/DC converter: and according to the control strategy and the command, the photovoltaic battery or the energy storage unit is responsible for converting the low-voltage direct current output by the photovoltaic battery or the energy storage unit into high-voltage direct current or converting the high-voltage direct current into low-voltage direct current to be stored in the energy storage unit.
The direct current/alternating current converter is used for converting the high-voltage direct current into high-voltage alternating current in an inverse mode and inputting the high-voltage alternating current into a power system;
a direct current motor: the high-voltage direct current generator is used for receiving high-voltage direct current electric energy and converting the high-voltage direct current electric energy into kinetic energy for rotating the motor;
an alternator: receiving the kinetic energy of the rotation of the motor, converting the kinetic energy into high-voltage alternating current electric energy, and inputting the high-voltage alternating current electric energy into an electric power system;
the power divider is: is responsible for distributing the direction of the energy output by the photovoltaic cells.
Preferably, the first dc/dc converter voltage conversion ratio is 37V/48V, the second dc/dc converter voltage conversion ratio is 37V/380V, and the third dc/dc converter voltage conversion ratio is: 37V/380V, the transformation ratio of the DC/AC converter is as follows: 380V/10000V.
Example two:
the second embodiment of the invention provides a photovoltaic grid-connected control method based on synchronous motor dynamic response sampling of a photovoltaic grid-connected system based on synchronous motor dynamic response sampling according to the first embodiment, which applies an upper computer,
acquiring the state of charge of the energy storage unit, the three-phase voltage of the port of the alternating-current generator, the illumination intensity, the three-phase current of the port of the alternating-current generator and the output limit power P of the photovoltaic cell0；
Based on the energy storage listThe state of charge of the cell, the three-phase voltage at the alternator port, the illumination intensity, the three-phase current at the alternator port and the limit power P of the output of the photovoltaic cell0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Output power P of the AC generator1The size of (d);
if the output limit power P of the photovoltaic cell is0Greater than or equal to the output power P of the alternator1；
And acquiring the charge state of the energy storage unit, and judging whether the residual capacity of the energy storage unit is greater than the minimum value of the allowable residual capacity or not based on the charge state of the energy storage unit.
Preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the residual electric quantity of the energy storage unit is larger than the allowable residual electric quantity, judging the output limit power P of the photovoltaic cell0Output power P of the AC generator1Whether the difference is greater than PsSaid P issThe maximum charge and discharge power of the energy storage unit is represented;
if yes, the power divider performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ； k 2 =（P 0 -P 1 - P s ）∕P 0 ； k 3 =P s ∕P 0 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =P 1 ∕P 0 ；k 2 =0；k 3 =（P 0 -P 1 ）∕P 0 。
preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the residual capacity of the energy storage unit is less than or equal to the allowable residual capacity, the power distributor performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ；k 2 =（P 0 -P 1 ）∕P 0 ； k 3 =0；
k 1—— a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 —the power divider is distributed to the proportionality coefficient of the energy storage unit.
Preferably, the energy storage unit-based state of charge, the three-phase voltage at the port of the alternator, the illumination intensity, the three-phase current at the port of the alternator and the limit power P of the output of the photovoltaic cell0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Output power P of the AC generator1The step of (a) further comprises;
if the output limit power P of the photovoltaic cell is0Less than the output power P of the alternator1And acquiring the charge state of the energy storage unit, and judging whether the residual capacity of the energy storage unit is greater than the minimum value of the allowable residual capacity or not based on the charge state of the energy storage unit.
Preferably, the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum allowable remaining capacity based on the state of charge of the energy storage unit includes:
if the ratio is larger than the preset value, the power divider performs power distribution according to the following proportionality coefficient:
k 1 =P 0 ∕P 1 ； k 2 =0；k 3 =（P 1 -P 0 ）∕ P 1 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =0；k 2 =0；k 3 = 1；
k 1 —a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 -a proportionality factor assigned by said power divider to said energy storage unit.
Preferably, the setting of the output current value and the output voltage value of the dc/ac converter is as follows:
I՚abc= I abc k2∕k1;
I՚abc-three phase currents output by the dc/ac converter;
I abc-three phase current at the alternator port;
U՚abc= U abc ;
U՚abc——three-phase voltage output by the direct current/alternating current converter;
U abc-the three phase voltage at the alternator port;
k1-a proportionality factor of the power of the alternator into the grid;
k2-a proportionality factor of the power of the dc/ac converter into the grid.
Further, the following channels are included:
signal 1: instantaneous values of current and voltage at the end of the alternator.
Signal 2: the power divider calculates the power ratio set point for power channel 1.
Signal 3: the power divider calculates the power ratio set point for power channel 2.
Signal 4: the current and voltage instantaneous set value input to the power system by the DC/AC converter.
Signal 5: the power divider is a power channel 3, i.e. an energy storage power set point.
Signal 6: and energy storage residual capacity information.
Signal 7: an illumination intensity signal.
The invention has the following advantages:
the traditional grid-connected form of the photovoltaic inverter can not provide inertia support and reactive dynamic support for a system, so that the stability of the system is poor. According to the photovoltaic grid-connected system and the control method based on synchronous motor dynamic response sampling, a small synchronous motor link is added between a photovoltaic grid-connected point and a grid-connected point, real-time sampling is conducted at a grid-connected position at an outlet of a synchronous motor, a synchronous motor dynamic response behavior reference set is formed and fed back to a photovoltaic grid-connected inverter control module, the photovoltaic grid-connected dynamic behavior is kept consistent with the synchronous motor, the photovoltaic grid-connected friendly property is remarkably improved on the premise that control delay is not increased, real inertia and reactive support are provided for a power grid, and therefore the operation stability of the system is improved.
Unless specifically stated otherwise, the relative steps, numerical expressions, and values of the components and steps set forth in these embodiments do not limit the scope of the present invention.
The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the system and the apparatus described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In addition, in the description of the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Finally, it should be noted that: the above-mentioned embodiments are only specific embodiments of the present invention, which are used for illustrating the technical solutions of the present invention and not for limiting the same, and the protection scope of the present invention is not limited thereto, although the present invention is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (4)
1. The utility model provides a photovoltaic grid-connected system based on synchronous machine dynamic response sampling which characterized in that includes:
the photovoltaic power generation system comprises a photovoltaic cell, an energy storage unit, a power divider, a first direct current/direct current converter, a second direct current/direct current converter, a third direct current/direct current converter, a direct current/alternating current converter, a direct current motor and an alternating current generator;
the photovoltaic cell is connected with the power divider, and the power divider is connected with the energy storage unit through the first direct current/direct current converter;
the power divider is connected through the second direct current/direct current converter, and the second direct current/direct current converter supplies power to the direct current motor;
an output shaft of the direct current motor drives the alternating current generator to generate electricity, and the electric energy of the alternating current generator is merged into a power grid;
the power divider is connected with the DC/AC converter through the third DC/DC converter, and the output side of the DC/AC converter is connected with an external power grid.
2. The grid-connected photovoltaic system based on synchronous machine dynamic response sampling according to claim 1, wherein the first dc/dc converter voltage transformation ratio is 37V/48V, the second dc/dc converter voltage transformation ratio is 37V/380V, and the third dc/dc converter voltage transformation ratio is: 37V/380V, the transformation ratio of the DC/AC converter is as follows: 380V/10000V.
3. A synchronous motor dynamic response sampling-based photovoltaic grid-connected control method of a synchronous motor dynamic response sampling-based photovoltaic grid-connected system according to claim 2, which is applied to an upper computer,
acquiring the state of charge of the energy storage unit, the three-phase voltage of the port of the alternating-current generator, the illumination intensity, the three-phase current of the port of the alternating-current generator and the output limit power P of the photovoltaic cell0；
Based on the state of charge of the energy storage unit, the three-phase voltage at the port of the alternating-current generator, the illumination intensity, the three-phase current at the port of the alternating-current generator and the output limit power P of the photovoltaic cell0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Communicate with the said transmitterOutput power P of the motor1The size of (d);
if the output limit power P of the photovoltaic cell is0Greater than or equal to the output power P of the alternator1；
Acquiring the charge state of the energy storage unit, judging whether the residual capacity of the energy storage unit is larger than the minimum value of the allowable residual capacity or not based on the charge state of the energy storage unit,
the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum value of the allowable remaining capacity based on the state of charge of the energy storage unit comprises:
if the residual electric quantity of the energy storage unit is larger than the allowable residual electric quantity, judging the output limit power P of the photovoltaic cell0Output power P of the AC generator1Whether the difference is greater than PsSaid P issThe maximum charge and discharge power of the energy storage unit is represented;
if yes, the power divider performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ； k 2 =（P 0 -P 1 - P s ）∕P 0 ； k 3 =P s ∕P 0 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =P 1 ∕P 0 ；k 2 =0；k 3 = （P 0 -P 1 ）∕P 0 ；
the step of acquiring the state of charge of the energy storage unit and determining whether the remaining capacity of the energy storage unit is greater than the minimum value of the allowable remaining capacity based on the state of charge of the energy storage unit comprises:
if the residual capacity of the energy storage unit is less than or equal to the allowable residual capacity, the power distributor performs power distribution according to the following proportionality coefficient:
k 1 =P 1 ∕P 0 ；k 2 =（P 0 -P 1 ）∕P 0 ； k 3 =0；
k 1—— a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 —the power divider is distributed to the proportionality coefficient of the energy storage unit.
4. The method of claim 3, wherein the energy storage unit is based on a state of charge of the energy storage unit, the alternator port three-phase voltage, the illumination intensity, the alternator port three-phase current, and the photovoltaic cell output limit power P0Obtaining the output power P of an alternator1Comparing the output limit power P of the photovoltaic cell0Output power P of the AC generator1Further comprising the steps of:
if the output limit power P of the photovoltaic cell is0Less than the output power P of the alternator1Obtaining the charge state of the energy storage unitThe state is judged whether the residual capacity of the energy storage unit is larger than the minimum value of the allowable residual capacity or not based on the state of charge of the energy storage unit;
if the ratio is larger than the preset value, the power divider performs power distribution according to the following proportionality coefficient:
k 1 =P 0 ∕P 1 ；k 2 =0；k 3 =（P 1 -P 0 ）∕P 1 ；
if not, the power distributor performs power distribution according to the following proportionality coefficients:
k 1 =0；k 2 =0；k 3 = 1；
k 1 —a proportionality coefficient of power of the alternator into a power grid;
k 2 -the proportionality factor of the power of the grid into which said dc/ac converter is incorporated;
k 3 -a proportionality factor assigned by said power divider to said energy storage unit;
the output current value and the output voltage value of the DC/AC converter are set as follows:
I՚abc= I abc k2∕k1;
I՚abc-three phase currents output by the dc/ac converter;
I abc-three phase current at the alternator port;
U՚abc= U abc ;
U՚abc——three-phase voltage output by the direct current/alternating current converter;
U abc-the three phase voltage at the alternator port;
k1-a proportionality factor of the power of the alternator into the grid;
k2-a proportionality factor of the power of the dc/ac converter into the grid.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242790A (en) * | 2014-09-29 | 2014-12-24 | 苏州克兰兹电子科技有限公司 | Wind-solar hybrid power generation system |
| CN106505551A (en) * | 2016-11-04 | 2017-03-15 | 国网江苏省电力公司扬州供电公司 | A kind of light storage DC power-supply system based on cooperative control device |
| CN109586343A (en) * | 2018-12-29 | 2019-04-05 | 国网天津市电力公司电力科学研究院 | Photovoltaic-energy-storing and power-generating system and method based on virtual synchronous generator control |
| CN110445182A (en) * | 2019-09-06 | 2019-11-12 | 集美大学 | Wind mobile platform wind-light storage direct current power system and control method are surveyed in a kind of highly reliable floatation type sea |
| WO2021077438A1 (en) * | 2019-10-25 | 2021-04-29 | 中国科学院电工研究所 | Large-scale photovoltaic direct-current series boosting grid-connected system having power balancers |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104821607B (en) * | 2015-05-15 | 2017-03-15 | 东北大学 | A kind of photovoltaic micro Power balance control method based on three end Collaborative Control |
| CN210927122U (en) * | 2019-12-10 | 2020-07-03 | 广东电网有限责任公司 | Optical storage type virtual synchronous machine |
-
2021
- 2021-10-26 CN CN202111245350.0A patent/CN113690946B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242790A (en) * | 2014-09-29 | 2014-12-24 | 苏州克兰兹电子科技有限公司 | Wind-solar hybrid power generation system |
| CN106505551A (en) * | 2016-11-04 | 2017-03-15 | 国网江苏省电力公司扬州供电公司 | A kind of light storage DC power-supply system based on cooperative control device |
| CN109586343A (en) * | 2018-12-29 | 2019-04-05 | 国网天津市电力公司电力科学研究院 | Photovoltaic-energy-storing and power-generating system and method based on virtual synchronous generator control |
| CN110445182A (en) * | 2019-09-06 | 2019-11-12 | 集美大学 | Wind mobile platform wind-light storage direct current power system and control method are surveyed in a kind of highly reliable floatation type sea |
| WO2021077438A1 (en) * | 2019-10-25 | 2021-04-29 | 中国科学院电工研究所 | Large-scale photovoltaic direct-current series boosting grid-connected system having power balancers |
Non-Patent Citations (2)
| Title |
|---|
| 光伏发电系统利用直流-异步电机并网控制方法的研究;孙颖等;《电机与控制应用》;20160110(第01期);72-76页 * |
| 光伏电源利用直流-同步电机并网控制方法的研究;孙颖等;《电力系统保护与控制》;20160815(第16期);78-83页 * |
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