An isolated grid system, energy storage power supply control method and system, and storage medium

Abstract

The application discloses an isolated network system, an energy storage power supply control method and system, and a storage medium. The isolated network system comprises an isolated network bus, a new energy power generation module connected with the isolated network bus, the new energy power generation module being used for providing electric energy for the isolated network bus, a switchable power load module connected with the isolated network bus, and an energy storage power supply device comprising a control unit and a three-phase chain module group, wherein the three-phase chain module group is connected with three-phase electric power of the isolated network bus, each phase chain module group comprises a connecting electric reactor and a plurality of energy storage submodules connected in series with each other, and the control unit is used for adjusting a working state of each energy storage submodule; and the control unit is connected with the new energy power generation module and the switchable power load module. The isolated network system can improve the operation stability of the isolated network, reduce the cost, and improve the economic benefits of the new energy power station.

Description

Technical Field

[0001] This invention relates to the field of power control technology, and in particular to an islanded grid system, an energy storage power control method, a system, and a storage medium. Background Technology

[0002] With the rapid development of new energy technologies such as wind power and photovoltaics, the problem of grid absorption of new energy power generation has become increasingly prominent. New energy power generation is intermittent, with large fluctuations in output, leading to poor grid stability. To address this issue, existing technologies employ the placement of switchable loads near new energy power plants, along with a certain capacity of energy storage to smooth peak and valley loads, forming an isolated grid that is not connected to the municipal power grid. However, the regulation of switchable loads is stepped, and existing energy storage uses an open-loop AC voltage output method, resulting in low control precision. These factors contribute to poor stability in isolated grid operation, making it prone to voltage collapse, and require large-capacity energy storage, leading to high system costs and low economic efficiency. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes an isolated grid system that can improve the stability of isolated grid operation, reduce costs, and improve the economic benefits of new energy power plants.

[0004] The present invention also provides an energy storage power supply control method, system, and computer-readable storage medium.

[0005] An isolated network system according to a first aspect of the present invention includes:

[0006] Isolated busbar;

[0007] A new energy power generation module is connected to the isolated grid bus, and the new energy power generation module is used to provide power to the isolated grid bus;

[0008] A switchable power load module is connected to the isolated grid bus.

[0009] The energy storage power supply device includes a control unit and a three-phase chain module group. The three-phase chain module group is electrically connected to the three phases of the isolated grid bus. Each phase of the chain module group includes a series-connected reactor and multiple energy storage sub-modules. The control unit is used to adjust the operating state of each energy storage sub-module. The control unit is connected to the new energy power generation module and the switchable load module.

[0010] The isolated network system according to embodiments of the present invention has at least the following beneficial effects:

[0011] An isolated grid can be established by supplying power to the isolated grid bus using an energy storage power device in a grid-based operation mode. Both the renewable energy generation module and the switchable load module are connected to the isolated grid bus. After the isolated grid is established, the renewable energy generation module begins supplying power to the bus. Control units are connected to both the renewable energy generation module and the switchable load module. The switchable load module adjusts its load power based on the current remaining energy of the three-phase chain module group: if the current remaining energy is greater than a preset energy threshold, the load power is increased until the generation power is within the preset rated power range; if the current remaining energy is less than the preset energy threshold, the load power is decreased until the generation power is within the preset rated power range. By adjusting the operating state of the three-phase chain module group through the control unit to adjust its output power, and by adjusting the load power through the switchable load module, the generation power of the renewable energy generation module can be stably adjusted to within the preset rated power range. This allows for stable operation of the isolated grid with a relatively small energy storage capacity, reducing costs. The isolated grid system of this invention can improve the stability of isolated grid operation, reduce costs, and improve the economic benefits of new energy power plants.

[0012] According to some embodiments of the present invention, each of the energy storage submodules includes:

[0013] Energy storage batteries are used to absorb or release electrical energy;

[0014] H-bridge power unit is used to convert energy between the energy storage battery and the isolated grid bus;

[0015] The battery management system is used to detect fault signals, temperature signals, DC voltage, and remaining battery power of the energy storage battery and upload them to the control unit, and to control the switching transistors of the H-bridge power unit to turn on and off according to the switching transistor turn-on and turn-off commands issued by the control unit.

[0016] According to a second aspect of the present invention, an energy storage power supply control method is applied to an islanded grid system as described in the first aspect of the present invention, the energy storage power supply control method comprising the following steps:

[0017] Acquire the AC voltage data of the isolated bus, the output current data of the three-phase chain module group, the DC voltage of each energy storage submodule in each phase of the chain module group, and the current remaining power of the three-phase chain module group;

[0018] Determine the average voltage of the sum of the DC voltages of each of the energy storage submodules in each phase of the chain module group;

[0019] The initial sinusoidal modulation wave of each phase of the chain module group is generated based on the AC voltage data, the output current data, and the preset voltage D-axis component setpoint and voltage Q-axis component setpoint.

[0020] Based on the average voltage value corresponding to each phase of the chain module group and the DC voltage of each energy storage submodule in each phase of the chain module group, the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group is adjusted one-to-one to obtain the equal-voltage sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group.

[0021] The switching transistor turn-on and turn-off commands for each energy storage submodule are determined one-to-one according to the equalizing sinusoidal modulation wave of each energy storage submodule in the three-phase chain module group, and the switching transistor turn-on and turn-off commands are sent one-to-one to each energy storage submodule in the three-phase chain module group.

[0022] The current remaining electrical energy is sent to the switchable load module, so that the switchable load module adjusts the load power according to the current remaining electrical energy and the power generation power of the new energy power generation module, so that the power generation power is stably adjusted to the preset rated power range.

[0023] The energy storage power supply control method according to embodiments of the present invention has at least the following beneficial effects:

[0024] The control unit can collect AC voltage data from the isolated bus, output current data from the three-phase chain module group, and DC voltage from each energy storage submodule in each phase chain module group. Based on the AC voltage data, output current data, and preset D-axis and Q-axis voltage setpoints, an initial sinusoidal modulation wave for each phase chain module group can be generated. By adjusting the phase shift angle of the initial sinusoidal modulation wave for each energy storage submodule in each phase chain module group according to the average voltage and DC voltage of each submodule, a voltage-equalized sinusoidal modulation wave for each submodule in each phase chain module group is obtained. This adjusts the output of each submodule, ensuring that their outputs are similar, thus extending their lifespan and avoiding frequent replacements of expired submodules. By sending the current remaining electrical energy of the three-phase chain module group to the switchable load module, the switchable load module can adjust its load power according to the current remaining electrical energy and the power generation capacity of the renewable energy generation module. By adjusting the output power of the three-phase chain module group and adjusting the load power through the switchable load module, the power generation capacity of the renewable energy generation module can be stably adjusted to a preset rated power range. This allows for stable operation of the isolated grid with a smaller energy storage capacity, reducing costs. The energy storage power control method of this invention ensures that the output of each energy storage submodule in each phase chain module group is similar, making the service life of each energy storage submodule closer, avoiding frequent replacements of energy storage submodules that have reached the end of their lifespan, improving the stability of isolated grid operation, reducing costs, and improving the economic benefits of renewable energy power plants.

[0025] According to some embodiments of the present invention, the step of adjusting the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group according to the average voltage value corresponding to each phase of the chain module group and the DC voltage of each energy storage submodule in each phase of the chain module group, to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group, includes the following steps:

[0026] Determine the voltage difference between the average voltage value corresponding to each phase of the chain module group and the DC voltage of each energy storage submodule in each phase of the chain module group;

[0027] Calculate the product of each voltage difference and the preset submodule voltage equalization ratio coefficient, and record the product as the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule.

[0028] Keeping the amplitude and frequency of the initial sinusoidal modulation wave unchanged, the initial angle of the initial sinusoidal modulation wave of each energy storage submodule is increased by the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule to obtain the equalizing sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group.

[0029] According to some embodiments of the present invention, the energy storage power supply control method further includes the following steps:

[0030] Obtain the power generation and the load power;

[0031] The operating mode of the three-phase chain module group is adjusted according to the power generation and the load power so that the sum of the power generation, the load power and the output power is within a preset stable power range. The operating mode includes an input power mode and an output power mode. The input power mode indicates that the three-phase chain module group absorbs electrical energy from the isolated grid bus, and the output power mode indicates that the three-phase chain module group provides electrical energy to the isolated grid bus.

[0032] According to some embodiments of the present invention, each of the energy storage submodules includes an energy storage battery and a battery management system, wherein the battery management system is used to detect the remaining battery power of the energy storage battery and upload it to the control unit.

[0033] According to some embodiments of the present invention, the load power adjustment process further includes the following steps:

[0034] If the sum of the current remaining electrical energy is less than the electrical energy threshold, the load power is controlled to be reduced until the power generation is within the rated power range.

[0035] According to a third aspect embodiment of the present invention, an energy storage power control system is applied to an islanded grid system as described in the first aspect embodiment above, the energy storage power control system comprising:

[0036] The data acquisition unit is used to acquire the AC voltage data of the isolated bus, the output current data of the three-phase chain module group, the DC voltage of each energy storage submodule in each phase of the chain module group, and the current remaining power of the three-phase chain module group.

[0037] The voltage average value calculation unit is used to calculate the average voltage of the sum of the DC voltages of each energy storage submodule in each phase of the chain module group;

[0038] An initial sinusoidal modulation wave generation unit is used to generate an initial sinusoidal modulation wave for each phase of the chain module group based on the AC voltage data, the output current data, and preset voltage D-axis component setpoints and voltage Q-axis component setpoints.

[0039] The voltage equalization control unit is used to adjust the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule according to the average voltage value corresponding to each phase of the chain module group and the DC voltage of each energy storage submodule in each phase of the chain module group, so as to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group.

[0040] The switching transistor turn-on / turn-off command generation unit is used to determine the switching transistor turn-on / turn-off command of each energy storage submodule according to the equalizing sinusoidal modulation wave of each energy storage submodule in the three-phase chain module group, and send the switching transistor turn-on / turn-off command to each energy storage submodule in the three-phase chain module group.

[0041] The remaining power determination unit is used to send the current remaining power to the switchable power load module, so that the switchable power load module adjusts the load power according to the current remaining power and the power generation power of the new energy power generation module, so that the power generation power is stably adjusted to a preset rated power range.

[0042] The energy storage power control system according to embodiments of the present invention has at least the following beneficial effects:

[0043] The data acquisition unit can acquire AC voltage data of the isolated bus, output current data of the three-phase chain module group, and DC voltage of each energy storage submodule in each phase chain module group. The initial sinusoidal modulation wave generation unit can generate the initial sinusoidal modulation wave for each phase chain module group based on the AC voltage data, output current data, and preset voltage D-axis and Q-axis component values. The voltage average calculation unit can determine the average voltage of the sum of the DC voltages of each energy storage submodule in each phase chain module group. The voltage equalization control unit can adjust the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule according to the corresponding average voltage of each phase chain module group and the DC voltage of each energy storage submodule in each phase chain module group, obtaining the voltage equalization sinusoidal modulation wave of each energy storage submodule in each phase chain module group. This adjusts the output of each energy storage submodule, ensuring that the output of each energy storage submodule in each phase chain module group is similar, thus making the service life of each energy storage submodule closer and avoiding frequent replacements of energy storage submodules that have reached the end of their service life. The remaining energy determination unit can send the current remaining energy of the three-phase chain module group to the switchable load module, allowing the switchable load module to adjust its load power based on the current remaining energy and the power generation of the renewable energy generation module. By adjusting the output power of the three-phase chain module group and adjusting the load power through the switchable load module, the power generation of the renewable energy generation module can be stably adjusted to a preset rated power range. This allows for stable operation of the isolated grid with a smaller energy storage capacity, reducing costs. The energy storage power control system of this embodiment ensures that the output of each energy storage submodule in each phase chain module group is similar, making the service life of each energy storage submodule closer, avoiding frequent replacements of energy storage submodules that have reached the end of their lifespan, improving the stability of isolated grid operation, reducing costs, and improving the economic benefits of renewable energy power plants.

[0044] According to a fourth aspect embodiment of the present invention, a computer-readable storage medium stores computer-executable instructions for performing the energy storage power control method as described in the second aspect embodiment above. Since the computer-readable storage medium employs all the technical solutions of the energy storage power control method of the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments.

[0045] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0046] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0047] Figure 1 This is a system block diagram of an isolated network system according to an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of a three-phase chain module group according to an embodiment of the present invention;

[0049] Figure 3 This is a schematic diagram of an energy storage submodule according to an embodiment of the present invention;

[0050] Figure 4 This is a flowchart of an energy storage power supply control method according to an embodiment of the present invention;

[0051] Figure 5 This is a waveform diagram of the effective value of the AC voltage output by a three-phase chain module group according to an embodiment of the present invention;

[0052] Figure 6 This is a waveform diagram of the output power of a three-phase chain module group according to an embodiment of the present invention;

[0053] Figure 7 This is a waveform diagram of the output current data of a three-phase chain module group according to an embodiment of the present invention.

[0054] Figure label:

[0055] Isolated busbar 100;

[0056] Photovoltaic power generation module 210, wind turbine module 220;

[0057] Sub-electrical load module 300;

[0058] Energy storage power supply device 400, energy storage submodule 410, energy storage battery 411, H-bridge power unit 412, battery management system 413. Detailed Implementation

[0059] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0060] In the description of this invention, the use of terms such as "first," "second," etc., is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0061] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0062] In the description of this invention, it should be noted that, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0063] The following will combine Figures 1 to 7 The isolated network system according to the first aspect of the present invention will be clearly and completely described. Obviously, the embodiments described below are some embodiments of the present invention, not all embodiments.

[0064] According to a first aspect of the present invention, an isolated grid system includes an isolated grid bus 100, a new energy power generation module, a switchable load module, and an energy storage device 400. The new energy power generation module is connected to the isolated grid bus 100 and is used to provide power to the isolated grid bus 100. The switchable load module is also connected to the isolated grid bus 100. The energy storage device 400 includes a control unit and a three-phase chain module group. The three-phase chain module group is electrically connected to the three phases of the isolated grid bus 100. Each phase chain module group includes a series-connected reactor L and multiple energy storage sub-modules 410. The control unit is used to adjust the operating state of each energy storage sub-module 410. The control unit is connected to the new energy power generation module and the switchable load module.

[0065] like Figure 1 As shown, the energy storage power supply device 400 provides power to the isolated grid bus 100 in a grid-connected operation mode to establish an isolated grid. The switchable load module includes a main load control unit and multiple sub-load modules 300. Each sub-load module 300 can be controlled by the main load control unit to maintain its operational status. All sub-load modules 300 are connected to the isolated grid bus 100. The sub-load modules 300 can be hydrogen electrolysis devices or other switchable load devices; no specific limitations are specified here. The new energy power generation module includes a main power generation control unit, multiple photovoltaic power generation modules 210, and multiple wind turbine modules 220. The main power generation control unit controls the operating status of the multiple photovoltaic power generation modules 210 and multiple wind turbine modules 220. All multiple photovoltaic power generation modules 210 and multiple wind turbine modules 220 are connected to the isolated grid bus 100.

[0066] like Figure 2As shown, each phase-chained module group includes interconnected connecting reactors L and multiple energy storage sub-modules 410. Each phase-chained module group also includes circuit breakers K connected in series with the connecting reactors L. There are three connecting reactors, namely L1, L2, and L3, and three circuit breakers, namely K1, K2, and K3. The control unit includes a main control system, a data acquisition module, an AC power supply, an uninterruptible power supply, a human-machine interface, and a communication module. The data acquisition module can acquire AC voltage data of the isolated bus 100, output current data of the three-phase chained module group, and DC voltage of each energy storage sub-module 410. The communication module can communicate with a remote monitoring terminal. The main control system can perform bidirectional data transmission with the battery management system 413 of each energy storage submodule 410. The main control system can send corresponding switch tube turn-on and turn-off commands to the battery management system 413 of each energy storage submodule 410. It can also receive fault signals, temperature signals, DC voltage, and remaining battery energy of the energy storage battery 411 uploaded by the battery management system 413 of each energy storage submodule 410.

[0067] After the isolated grid is established, the new energy power generation modules begin to supply power to the isolated grid bus 100. The main control unit of the power load adjusts the load power according to the current remaining power of the three-phase chain module group: if the current remaining power is greater than the preset power threshold, the sub-load modules 300 are continuously connected to increase the load power; if the sum of the current remaining power is less than the power threshold, the sub-load modules 300 are continuously disconnected to reduce the load power until the power generation is within the rated power range. This allows the stable operation of the isolated grid to be guaranteed with a relatively small energy storage capacity, reducing costs and improving the economic benefits of the new energy power station.

[0068] According to an embodiment of the present invention, an isolated grid system can be established by supplying power to the isolated grid bus 100 through an energy storage power device 400 in a grid-type operation mode. Both the new energy generation module and the switchable load module are connected to the isolated grid bus 100. After the isolated grid is established, the new energy generation module begins to supply power to the isolated grid bus 100. A control unit is connected to both the new energy generation module and the switchable load module. The switchable load module can adjust its load power according to the current remaining power of the three-phase chain module group: if the current remaining power is greater than a preset power threshold, the load power is increased until the power generation is within the preset rated power range; if the current remaining power is less than the preset power threshold, the load power is decreased until the power generation is within the preset rated power range. By adjusting the operating state of the three-phase chain module group through the control unit to adjust its output power, and by adjusting the load power through the switchable load module, the power generation of the new energy generation module can be stably adjusted to within the preset rated power range. This allows for stable operation of the isolated grid with a smaller energy storage capacity, reducing costs. The isolated grid system of this invention can improve the stability of isolated grid operation, reduce costs, and improve the economic benefits of new energy power plants.

[0069] In some embodiments of the present invention, reference is made to Figure 2 and Figure 3 Each energy storage submodule 410 includes an energy storage battery 411, an H-bridge power unit 412, and a battery management system 413. The energy storage battery 411 absorbs or releases electrical energy; the H-bridge power unit 412 converts energy between the energy storage battery 411 and the islanded bus 100; the battery management system 413 detects fault signals, temperature signals, DC voltage, and remaining battery energy of the energy storage battery 411 and uploads them to the control unit, and controls the switching on and off of the H-bridge power unit 412 according to the switching commands issued by the control unit. The battery management system 413 detects fault signals, temperature signals, DC voltage, and remaining battery energy of the energy storage battery 411 in real time and uploads them to the control unit, and can also remotely transmit them to a remote monitoring terminal for remote monitoring. The battery management system 413 of each energy storage submodule 410 receives corresponding switching commands sent by the control unit. It should be noted that the working principle of the H-bridge power unit 412 is existing technology known to those skilled in the art, and will not be described in detail here.

[0070] The following will combine Figures 1 to 7 The energy storage power supply control method according to the second aspect of the present invention will be clearly and completely described. Obviously, the embodiments described below are some embodiments of the present invention, not all embodiments.

[0071] According to a second aspect of the present invention, an energy storage power supply control method is applied to an isolated grid system as described in the first aspect of the present invention. The energy storage power supply control method includes the following steps:

[0072] Acquire AC voltage data of isolated bus 100, output current data of three-phase chain module group, DC voltage of each energy storage submodule 410 in each phase chain module group, and current remaining power of the three-phase chain module group;

[0073] Determine the average voltage of the sum of the DC voltages of each energy storage submodule 410 in each phase chain module group;

[0074] The initial sinusoidal modulation wave of each phase chain module group is generated based on the AC voltage data, output current data, and preset voltage D-axis component setpoint and voltage Q-axis component setpoint.

[0075] Based on the average voltage of each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group, the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group is adjusted one by one to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group.

[0076] Based on the equalizing sinusoidal modulation wave of each energy storage submodule 410 in the three-phase chain module group, determine the switching transistor turn-on and turn-off commands of each energy storage submodule 410 in a one-to-one correspondence, and send the switching transistor turn-on and turn-off commands to each energy storage submodule 410 in the three-phase chain module group in a one-to-one correspondence.

[0077] The remaining electrical energy is sent to the switchable load modules so that the switchable load modules can adjust the load power according to the current remaining electrical energy and the power generation of the new energy generation modules, so that the power generation is stably adjusted to the preset rated power range.

[0078] The energy storage power supply device 400 supplies power to the isolated grid bus 100 in a grid-connected operation mode to establish an isolated grid. The switchable load modules include a main load control unit and multiple sub-load modules 300. Each sub-load module 300 can be controlled by the main load control unit to maintain its operational status. All sub-load modules 300 are connected to the isolated grid bus 100. The sub-load modules 300 can be hydrogen electrolysis devices or other switchable load devices; no specific limitations are imposed here. The new energy power generation module includes a main power generation control unit, multiple photovoltaic power generation modules 210, and multiple wind turbine modules 220. The main power generation control unit controls the operating status of the photovoltaic power generation modules 210 and the wind turbine modules 220. All photovoltaic power generation modules 210 and the wind turbine modules 220 are connected to the isolated grid bus 100.

[0079] The AC voltage data is the instantaneous value U of the three-phase AC voltage of the isolated bus 100. ab U bc U ca The output current data is the three-phase output current I of the three-phase chain module group. a I b I c .

[0080] In some embodiments, an initial sinusoidal modulation wave S of the three-phase chain module group is generated based on AC voltage data, output current data, and preset voltage D-axis component setpoints and voltage Q-axis component setpoints. A S B S C This includes the following steps:

[0081] Using the AC voltage data, a Park transformation is performed to obtain the DC voltage D-axis component U. d_ctrl and DC voltage Q-axis component U q_ctrl ;

[0082] Based on the DC voltage D-axis component U d_ctrl DC voltage Q-axis component U q_ctrl The preset voltage D-axis component setpoint U d_ref and the preset voltage Q-axis component setpoint U q_ref Perform PI control to obtain the current D-axis component setpoint I. d_ref and the given value I of the Q-axis component of the current q_ref ;

[0083] The D-axis component I of the DC current is obtained by performing Park transformation on the output current data. sd and DC current Q-axis component I sq ;

[0084] Based on the D-axis component I of the DC current sd DC current Q-axis component I sq Current D-axis component given value I d_ref Current Q-axis component given value I q_ref After PI regulation, DC voltage D-axis component U is applied respectively. d_ctrl and DC voltage Q-axis component U q_ctrl Then, perform the inverse Park transform to generate the initial sinusoidal modulation wave S of the three-phase chain module group. A S B S C .

[0085] It should be noted that Park transformation, inverse Park transformation, and PI regulation are all existing technologies known to those skilled in the art, and will not be elaborated upon here.

[0086] Set the initial sinusoidal modulation wave S A S B S C The initial angle is 0. The larger the voltage difference between the DC voltage of each energy storage submodule 410 in each phase chain module group and the average voltage of the sum of the DC voltages of each energy storage submodule 410 in the corresponding phase chain module group, the larger the additional phase shift angle of the initial sinusoidal modulation wave corresponding to the energy storage submodule 410. Different phase shift angles result in different power angles between the output voltage of the energy storage submodule 410 and the AC voltage of the isolated grid bus 100, which in turn leads to different active power input / output and different output power of each energy storage submodule 410. It is necessary to ensure that the output power of each energy storage submodule 410 in each phase chain module group is close, so that the service life of each energy storage submodule 410 is closer, avoiding multiple replacements of energy storage submodules 410 that have reached the end of their service life.

[0087] The remaining energy of each energy storage battery 411 can be sent to the control unit through the corresponding battery management system 413. The control unit determines the current remaining energy of the three-phase chain module group based on the sum of the remaining energy of each energy storage battery 411, and sends the current remaining energy to the switchable load modules. The switchable load modules determine the relationship between the current remaining energy and a preset energy threshold. If the current remaining energy is greater than the preset energy threshold, sub-load modules 300 are continuously connected to increase the load power; if the sum of the current remaining energy is less than the energy threshold, sub-load modules 300 are continuously disconnected to reduce the load power until the power generation is within the rated power range. This allows for stable operation of the isolated grid with a relatively small energy storage capacity, reducing costs. It should be noted that the specific value of the energy threshold needs to be determined according to the actual situation and is not limited here.

[0088] According to the energy storage power supply control method of this embodiment, the control unit can collect AC voltage data of the isolated bus 100, output current data of the three-phase chain module group, and DC voltage of each energy storage submodule 410 in each phase chain module group. Based on the AC voltage data, output current data, and preset voltage D-axis component setpoints and voltage Q-axis component setpoints, an initial sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group can be generated. Based on the average voltage of each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group, the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group is adjusted one-to-one to obtain the voltage-equalizing sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group. This adjusts the output of each energy storage submodule 410, ensuring that the output of each energy storage submodule 410 in each phase chain module group is close, thereby making the service life of each energy storage submodule 410 closer and avoiding multiple replacements of energy storage submodules 410 that have reached the end of their service life. By sending the current remaining electrical energy of the three-phase chain module group to the switchable load module, the switchable load module can adjust the load power according to the current remaining electrical energy and the power generation power of the new energy generation module. By adjusting the output power of the three-phase chain module group and adjusting the load power through the switchable load module, the power generation of the new energy power generation module can be stably adjusted to the preset rated power range. This allows for stable operation of the isolated grid with a smaller energy storage capacity, reducing costs. The energy storage power control method of this embodiment ensures that the output of each energy storage submodule 410 in each phase chain module group is similar, making the service life of each energy storage submodule 410 more similar, avoiding frequent replacements of energy storage submodules 410 that have reached the end of their lifespan, improving the stability of isolated grid operation, reducing costs, and increasing the economic benefits of the new energy power plant.

[0089] In some embodiments of the present invention, reference is made to Figure 2 and Figure 3 The phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410 is adjusted one-to-one according to the average voltage of each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group, to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group, including the following steps:

[0090] Determine the voltage difference between the average voltage of each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group.

[0091] Calculate the product of each voltage difference and the preset submodule voltage equalization ratio coefficient, and record the product as the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410.

[0092] Keeping the amplitude and frequency of the initial sinusoidal modulation wave unchanged, the initial angle of the initial sinusoidal modulation wave of each energy storage submodule 410 is increased one-to-one by the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410, so as to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group.

[0093] The greater the voltage difference between the DC voltage of each energy storage submodule 410 in each phase chain module group and the average voltage of the sum of the DC voltages of each energy storage submodule 410 in the corresponding phase chain module group, the greater the additional phase shift angle of the initial sinusoidal modulation wave corresponding to the energy storage submodule 410. Different phase shift angles result in different power angles between the output voltage of the energy storage submodule 410 and the AC voltage of the isolated grid bus 100, which in turn leads to different active power input / output and different output power of each energy storage submodule 410. This ensures that the output power of each energy storage submodule 410 in each phase chain module group is similar, thereby making the service life of each energy storage submodule 410 more similar and avoiding multiple replacements of energy storage submodules 410 that have reached the end of their service life.

[0094] In some embodiments of the present invention, reference is made to Figure 1 and Figure 2 The energy storage power supply control method also includes the following steps:

[0095] Obtain power generation and load power;

[0096] The operating mode of the three-phase chain module group is adjusted according to the power generation and load power so that the sum of the power generation, load power and output power is within the preset stable power range. The operating mode includes input power mode and output power mode. Input power mode indicates that the three-phase chain module group absorbs electrical energy from the isolated grid bus 100, and output power mode indicates that the three-phase chain module group provides electrical energy to the isolated grid bus 100.

[0097] The energy storage power supply device 400 provides power to the isolated grid bus 100 in a grid-connected operation mode to establish an isolated grid. The new energy power generation module and the switchable load module are both connected to the isolated grid bus 100. The switchable load module includes multiple sub-load modules 300, each of which can be switched.

[0098] After the isolated grid is established, the renewable energy generation module begins to supply power to the isolated grid bus 100, while simultaneously charging the three-phase chain module group. At this time, the three-phase chain module group operates in input power mode. As the remaining energy of the three-phase chain module group continuously increases, when it exceeds a preset energy threshold, the sub-load module 300 is activated. At this point, the power generation of the renewable energy generation module is less than the load power of the activated sub-load module 300. The operating mode of the three-phase chain module group is then adjusted from input power mode to output power mode to compensate for the insufficient power generation of the renewable energy generation module, ensuring that the sum of power generation, load power, and output power remains within a preset stable power range. After the sub-load module 300 is activated, the power generation of the renewable energy generation module continues to increase and exceeds the load power. At this point, the operating mode of the three-phase chain module group is adjusted from output power mode to input power mode to absorb the excess power generation of the renewable energy generation module. Following this pattern, the power generation of the new energy power generation module can be stably adjusted to the preset rated power range. At this point, the power generation and load power gradually reach a balance. Moreover, the output power and output current of the three-phase chain module group are very small, thus enabling the stable operation of the isolated grid with a small energy storage capacity and reducing costs.

[0099] In some embodiments of the present invention, reference is made to Figures 1 to 3 Each energy storage submodule 410 includes an energy storage battery 411 and a battery management system 413. The battery management system 413 detects the remaining energy of the energy storage batteries 411 and uploads it to the control unit. The sum of the remaining energy of each energy storage battery 411 is the current remaining energy of the three-phase chain module group. The remaining energy of each energy storage battery 411 can be sent to the control unit through the corresponding battery management system 413. The control unit determines the current remaining energy of the three-phase chain module group based on the sum of the remaining energy of each energy storage battery 411 and sends the current remaining energy to the switchable load module. The switchable load module determines the relationship between the current remaining energy and a preset energy threshold. The switchable load module includes multiple sub-load modules 300, each of which can be switched. If the current remaining electrical energy is greater than the preset electrical energy threshold, sub-load modules 300 are continuously activated to increase load power; if the sum of the current remaining electrical energy is less than the electrical energy threshold, sub-load modules 300 are continuously deactivated to reduce load power until the power generation is within the rated power range. This allows for stable operation of the isolated grid with a relatively small energy storage capacity, reducing costs. It should be noted that the specific value of the electrical energy threshold needs to be determined based on the actual situation and is not limited here.

[0100] Figure 5 This is a waveform diagram of the effective value of the AC voltage output by a three-phase chain module group according to an embodiment of the present invention; Figure 6 This is a waveform diagram of the output power of a three-phase chain module group according to an embodiment of the present invention; Figure 7 This is a waveform diagram of the output current data of a three-phase chain module group according to an embodiment of the present invention. Figures 5 to 7 As can be seen from the data, using the energy storage power control method of this embodiment, after 2.00s, the waveforms of the effective value of the AC voltage output by the three-phase chain module group, the waveform of the output power output by the three-phase chain module group, and the waveform of the output current data output by the three-phase chain module group all gradually stabilize. The energy storage power control method of this embodiment can improve the stability of islanded grid operation.

[0101] To better demonstrate the advantages of the energy storage power supply control method of the present invention, a specific example is provided below. However, the specific numerical values ​​mentioned below should not be considered as limitations on the present invention.

[0102] 1) First, start the energy storage power supply device 400. After starting, the energy storage power supply device 400 supplies power to the isolated grid bus 100 to establish the isolated grid. At this time, the effective value of the AC voltage of the isolated grid bus 100 reaches the set value of 1.0 Pu and remains stable. DC current D-axis component I sd and DC current Q-axis component I sq Each gradually follows the given value I of the current D-axis component. d_ref and the given value I of the Q-axis component of the current q_ref To achieve stability;

[0103] 2) At 1 second, the new energy power generation module starts generating electricity, and the power generation gradually increases from 0. The effective value of the AC voltage of the isolated grid bus 100 gradually increases. The working mode of the three-phase chain module group is the input power mode, the input power gradually increases, and the stored current remaining electrical energy continuously increases.

[0104] 3) At 1.3 seconds, the 25MW capacity switchable load module is put into islanded operation. The power generation of the renewable energy generation module is less than the load power of the switchable load module. The three-phase chain module group switches from input power mode to output power mode to supplement the insufficient power generation of the renewable energy generation module. The DC current D-axis component I sd After a step change, it gradually stabilizes and follows the given value I of the D-axis component of the current. d_ref ;

[0105] 4) After the switchable load module is put into operation, the power generation of the new energy power generation module continues to increase and exceeds the load power, and the three-phase chain module group changes from output power mode to input power mode.

[0106] 5) At 1.8 seconds, another 26MW of switchable load modules were put into islanded operation, and the three-phase chain module group once again switched from input power mode to output power mode, with the DC current D-axis component I... sd After a step change, it gradually stabilizes and follows the given value I of the D-axis component of the current. d_ref ;

[0107] 6) As the power generation capacity of the new energy power generation module gradually reaches the rated 50MW, the power generation capacity and load capacity gradually reach a balance. The effective value of the AC voltage of the isolated grid bus 100 is stabilized at the set value under the control of the control unit. The output power and output current of the three-phase chain module group are very low, so that the stable operation of the isolated grid can be guaranteed with a small energy storage power capacity, thus reducing costs.

[0108] The following will combine Figures 1 to 7 The energy storage power control system according to the third aspect of the present invention will be clearly and completely described. Obviously, the embodiments described below are some embodiments of the present invention, not all embodiments.

[0109] According to a third aspect of the present invention, an energy storage power control system is applied to an isolated grid system of the first aspect of the present invention. The energy storage power control system includes a data acquisition unit, a voltage average value calculation unit, an initial sinusoidal modulation wave generation unit, a voltage equalization control unit, a switch transistor turn-on / turn-off command generation unit, and a remaining energy determination unit.

[0110] The data acquisition unit is used to acquire AC voltage data of the isolated bus 100, output current data of the three-phase chain module group, DC voltage of each energy storage submodule 410 in each phase chain module group, and the current remaining power of the three-phase chain module group.

[0111] The voltage average value calculation unit is used to calculate the average voltage of the sum of the DC voltages of each energy storage submodule 410 in each phase chain module group.

[0112] The initial sinusoidal modulation wave generation unit is used to generate the initial sinusoidal modulation wave of each phase chain module group based on AC voltage data, output current data, and preset voltage D-axis component setpoints and voltage Q-axis component setpoints.

[0113] The voltage equalization control unit is used to adjust the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410 according to the average voltage value corresponding to each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group, so as to obtain the voltage equalization sinusoidal modulation wave of each energy storage submodule 410 in each phase chain module group.

[0114] The switching transistor turn-on and turn-off command generation unit is used to determine the switching transistor turn-on and turn-off command of each energy storage submodule 410 according to the equalizing sinusoidal modulation wave of each energy storage submodule 410 in the three-phase chain module group, and send the switching transistor turn-on and turn-off command to each energy storage submodule 410 in the three-phase chain module group.

[0115] The remaining power determination unit is used to send the current remaining power to the switchable load module, so that the switchable load module can adjust the load power according to the current remaining power and the power generation of the new energy generation module, so that the power generation is stably adjusted to the preset rated power range.

[0116] The greater the voltage difference between the DC voltage of each energy storage submodule 410 in each phase chain module group and the average voltage of the sum of the DC voltages of each energy storage submodule 410 in the corresponding phase chain module group, the greater the additional phase shift angle of the initial sinusoidal modulation wave corresponding to the energy storage submodule 410. Different phase shift angles result in different power angles between the output voltage of the energy storage submodule 410 and the AC voltage of the isolated grid bus 100, which in turn leads to different active power input / output and different output power of each energy storage submodule 410. It is necessary to ensure that the output power of each energy storage submodule 410 in each phase chain module group is similar, so as to make the service life of each energy storage submodule 410 more similar and avoid repeated replacement of energy storage submodules 410 that have reached the end of their service life.

[0117] The remaining energy of each energy storage battery 411 can be sent to the control unit through the corresponding battery management system 413. The control unit determines the current remaining energy of the three-phase chain module group based on the sum of the remaining energy of each energy storage battery 411, and sends the current remaining energy to the switchable load modules. The switchable load modules determine the relationship between the current remaining energy and a preset energy threshold. If the current remaining energy is greater than the preset energy threshold, sub-load modules 300 are continuously connected to increase the load power; if the sum of the current remaining energy is less than the energy threshold, sub-load modules 300 are continuously disconnected to reduce the load power until the power generation is within the rated power range. This allows for stable operation of the isolated grid with a relatively small energy storage capacity, reducing costs. It should be noted that the specific value of the energy threshold needs to be determined according to the actual situation and is not limited here.

[0118] According to an embodiment of the energy storage power control system of the present invention, the data acquisition unit can acquire AC voltage data of the isolated bus 100, output current data of the three-phase chain module group, and DC voltage of each energy storage submodule 410 in each phase chain module group. The initial sinusoidal modulation wave generation unit can generate an initial sinusoidal modulation wave for each energy storage submodule 410 in each phase chain module group based on the AC voltage data, output current data, and preset voltage D-axis component and voltage Q-axis component values. The voltage average value calculation unit can determine the average voltage of the sum of the DC voltages of each energy storage submodule 410 in each phase chain module group. The voltage equalization control unit adjusts the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule 410 according to the average voltage of each phase chain module group and the DC voltage of each energy storage submodule 410 in each phase chain module group. This results in a voltage equalization sinusoidal modulation wave for each energy storage submodule 410 in each phase chain module group, making the output of each energy storage submodule 410 in each phase chain module group similar. This extends the service life of each energy storage submodule 410, avoiding frequent replacements of energy storage submodules 410 that have reached the end of their service life. The remaining power determination unit sends the current remaining power of the three-phase chain module group to the switchable load module, allowing the switchable load module to adjust its load power based on the current remaining power and the power generation of the new energy generation module. By adjusting the output power of the three-phase chain module group and adjusting the load power through the switchable load module, the power generation of the new energy generation module can be stably adjusted to a preset rated power range. This allows for stable operation of the isolated grid with a smaller energy storage capacity, reducing costs. The energy storage power control system of this invention can ensure that the output of each energy storage submodule 410 in each phase chain module group is similar, making the service life of each energy storage submodule 410 more similar, avoiding multiple replacements of energy storage submodules 410 that have reached the end of their service life, improving the stability of islanded grid operation, reducing costs, and improving the economic benefits of new energy power plants.

[0119] Furthermore, the control unit, electrical load control unit, and power generation control unit in this embodiment of the invention all include: a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor and memory can be connected via a bus or other means.

[0120] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0121] The non-transient software program and instructions required to implement the energy storage power control method of the above embodiments are stored in the memory. When executed by the processor, the energy storage power control method of the above embodiments is executed.

[0122] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0123] Furthermore, a fourth aspect of the present invention provides a computer-readable storage medium storing computer-executable instructions that are executed by a processor or controller, for example, by a processor in the aforementioned control unit, such that the processor performs the energy storage power control method described in the above embodiments.

[0124] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0125] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An isolated grid system, characterized by, include: Isolated busbar; A new energy power generation module is connected to the isolated grid bus, and the new energy power generation module is used to provide power to the isolated grid bus; A switchable power load module is connected to the isolated grid bus. An energy storage power supply device includes a control unit and a three-phase chain module group. The three-phase chain module group is electrically connected to the three phases of the isolated grid bus. Each phase of the chain module group includes a series-connected reactor and multiple energy storage sub-modules. The control unit is used to adjust the operating state of each energy storage sub-module. The control unit is connected to the new energy power generation module and the switchable load module. The control unit is used to perform the following steps: Acquire the AC voltage data of the isolated bus, the output current data of the three-phase chain module group, the DC voltage of each energy storage submodule in each phase of the chain module group, and the current remaining power of the three-phase chain module group; Determine the average voltage of the sum of the DC voltages of each of the energy storage submodules in each phase of the chain module group; The initial sinusoidal modulation wave of each phase of the chain module group is generated based on the AC voltage data, the output current data, and the preset voltage D-axis component setpoint and voltage Q-axis component setpoint. Based on the average voltage value corresponding to each phase of the chain module group and the DC voltage of each energy storage submodule in each phase of the chain module group, the phase shift angle of the initial sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group is adjusted one-to-one to obtain the equal-voltage sinusoidal modulation wave of each energy storage submodule in each phase of the chain module group. The switching transistor turn-on and turn-off commands for each energy storage submodule are determined one-to-one according to the equalizing sinusoidal modulation wave of each energy storage submodule in the three-phase chain module group, and the switching transistor turn-on and turn-off commands are sent one-to-one to each energy storage submodule in the three-phase chain module group. The current remaining electrical energy is sent to the switchable load module, so that the switchable load module adjusts the load power according to the current remaining electrical energy and the power generation power of the new energy power generation module, so that the power generation power is stably adjusted to the preset rated power range.

2. The island system of claim 1, wherein, Each of the aforementioned energy storage submodules includes: Energy storage batteries are used to absorb or release electrical energy; H-bridge power unit is used to convert energy between the energy storage battery and the isolated grid bus; The battery management system is used to detect fault signals, temperature signals, DC voltage, and remaining battery power of the energy storage battery and upload them to the control unit, and to control the switching transistors of the H-bridge power unit to turn on and off according to the switching transistor turn-on and turn-off commands issued by the control unit.

3. A method for controlling an energy storage power source, characterized in that, Applied to the islanded grid system as described in claim 1 or 2, the energy storage power control method includes the following steps: Acquire the AC voltage data of the isolated bus, the output current data of the three-phase chain module group, the DC voltage of each energy storage submodule in each phase of the chain module group, and the current remaining power of the three-phase chain module group; determining a voltage average value of a sum of the direct current voltage of each of the energy storage sub-modules in the chain module group of each phase; generating an initial sinusoidal modulation wave of the chain module group of each phase according to the alternating current voltage data, the output current data, and preset voltage D-axis component given value and voltage Q-axis component given value; adjusting a phase shift angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules according to the corresponding voltage average value of the chain module group of each phase and the direct current voltage of each of the energy storage sub-modules in the chain module group of each phase, to obtain a voltage-equalizing sinusoidal modulation wave of each of the energy storage sub-modules in the chain module group of each phase; determining a switch tube turn-on and turn-off command of each of the energy storage sub-modules according to the voltage-equalizing sinusoidal modulation wave of each of the energy storage sub-modules in the three-phase chain module group, and transmitting the switch tube turn-on and turn-off command of each of the energy storage sub-modules to the three-phase chain module group one by one; transmitting the current residual electric energy to the switchable power consumption load module, so that the switchable power consumption load module adjusts the load power according to the current residual electric energy and the power generation power of the new energy power generation module, so that the power generation power is stably adjusted to be within a preset rated power range.

4. The energy storage power source control method of claim 3, wherein, The adjusting of the phase shift angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules according to the corresponding voltage average value of the chain module group of each phase and the direct current voltage of each of the energy storage sub-modules in the chain module group of each phase to obtain the voltage-equalizing sinusoidal modulation wave of each of the energy storage sub-modules in the chain module group of each phase comprises the following steps: determining a voltage difference value between the voltage average value corresponding to the chain module group of each phase and the direct current voltage of each of the energy storage sub-modules in the chain module group of each phase; calculating a product of each of the voltage difference values and a preset sub-module voltage-equalizing proportionality coefficient, and recording the product as the phase shift angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules one by one; keeping the amplitude and frequency of the initial sinusoidal modulation wave unchanged, and increasing the initial angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules by the phase shift angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules one by one to obtain the voltage-equalizing sinusoidal modulation wave of each of the energy storage sub-modules in the chain module group of each phase.

5. The energy storage power source control method of claim 3, wherein, The energy storage power supply control method further comprises the following steps: obtaining the power generation power and the load power; adjusting the working mode of the three-phase chain module group according to the power generation power and the load power, so that the sum of the power generation power, the load power and the output power is within a preset stable power range, the working mode comprising an input power mode and an output power mode, the input power mode representing that the three-phase chain module group absorbs electric energy from the isolated network bus, and the output power mode representing that the three-phase chain module group provides electric energy to the isolated network bus.

6. The energy storage power source control method of claim 3, wherein Each of the energy storage sub-modules comprises an energy storage battery and a battery management system for detecting battery residual power of the energy storage battery and uploading to the control unit.

7. The energy storage power source control method of claim 3, wherein The adjusting process of the load power further comprises the following steps: If the sum of the current residual power is less than the power threshold, the load power is controlled to be reduced until the power generation power is within the rated power range.

8. An energy storage power supply control system, characterized by, The energy storage power control system is applied to the isolated grid system as claimed in claim 1 or 2, and comprises: a data acquisition unit for acquiring AC voltage data of the isolated grid bus, output current data of the three-phase chain module group, DC voltage of each of the energy storage sub-modules in each phase of the chain module group, and current residual power of the three-phase chain module group; a voltage average value calculation unit for calculating a voltage average value of the sum of the DC voltages of each of the energy storage sub-modules in each phase of the chain module group; an initial sinusoidal modulation wave generation unit for generating an initial sinusoidal modulation wave of each phase of the chain module group according to the AC voltage data, the output current data, and preset voltage D-axis component given value and voltage Q-axis component given value; a voltage equalization control unit for adjusting a phase shift angle of the initial sinusoidal modulation wave of each of the energy storage sub-modules according to the voltage average value corresponding to each phase of the chain module group and the DC voltage of each of the energy storage sub-modules in each phase of the chain module group, to obtain a voltage equalization sinusoidal modulation wave of each of the energy storage sub-modules in each phase of the chain module group; a switch tube turn-on and turn-off command generation unit for determining a switch tube turn-on and turn-off command of each of the energy storage sub-modules according to the voltage equalization sinusoidal modulation wave of each of the energy storage sub-modules in the three-phase chain module group, and sending the switch tube turn-on and turn-off command of each of the energy storage sub-modules to each of the energy storage sub-modules in the three-phase chain module group; a residual power determination unit for sending the current residual power to the switchable power consumption load module, so that the switchable power consumption load module adjusts the load power according to the current residual power and the power generation power of the new energy power generation module, so that the power generation power is stably adjusted to be within the preset rated power range.

9. A computer-readable storage medium storing computer-executable instructions, characterized in that, The computer executable instructions are used to execute the energy storage power control method as claimed in any one of claims 3 to 7.

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