Energy management control method and system in independent network construction scene of optical storage micro-grid

Abstract

The invention discloses an energy management control method and system in an independent grid construction scene of a light storage micro-grid, and relates to the field of micro-grid energy management, and the method comprises the steps: obtaining micro-grid parameters, calculating the needed active and reactive power adjusting variables, and distributing the active and reactive power adjusting variables to energy storage units according to a preset sequence; updating the droop coefficient according to the number of the voltage control sources, and recalculating the power regulation quantity; distributing active power adjustment according to a preset rule; setting and adjusting the target exchange power of the energy storage unit; a specific photovoltaic inverter is selected for switching; after switching, the charging and discharging power of the energy storage unit is adjusted according to the residual power deviation for balancing; according to the invention, through coordinated scheduling of the energy storage units of the micro-grid, the frequency and voltage stability requirements under independent grid construction are met, the SOC stability of the energy storage units is improved, and the power supply reliability and the safe and stable operation capability of the optical storage micro-grid are enhanced.

Description

Technical Field

[0001] The present invention relates to the field of microgrid energy management, and in particular to an energy management control method and system in an independent networking scenario of a photovoltaic energy storage microgrid. Background Art

[0002] As an advanced structural form to promote photovoltaic consumption, the photovoltaic storage microgrid effectively organizes photovoltaic power generation units, energy storage units, and local loads. When the photovoltaic storage microgrid is independently networked and operated, the photovoltaic power generation in the microgrid system has the characteristics of randomness and volatility, and the load itself also has a certain volatility. The energy management system needs to dispatch the charging and discharging power of the energy storage unit to adjust the power difference between the source and load in the system to achieve the stability of the frequency and voltage of the constructed microgrid system, and at the same time ensure that the instantaneous fluctuation of the micro source and load of the microgrid system does not exceed the power adjustment range of the energy storage unit. In order to meet the needs of long-term independent network operation of the photovoltaic storage microgrid, the energy management system needs to stably control the SOC of the energy storage unit.

[0003] The existing technology usually adopts the following methods to solve the energy management problem in the scenario of independent networking of photovoltaic storage microgrid: centralized energy management: a central controller is used to centrally dispatch the charging and discharging power of energy storage units and the switching of photovoltaic inverters to maintain the stability of system frequency and voltage. Although this method can effectively balance the system power, relying on the central controller may lead to slow response speed, and it is difficult to ensure the stability of the system in the event of communication failure; distributed energy management: multiple local controllers are used to control each energy storage unit and photovoltaic inverter respectively, and coordination is achieved through the communication network. This method enhances the robustness and response speed of the system, but the communication complexity between distributed controllers is high, and data asynchrony or communication delay problems are prone to occur; rule-based control strategy: the charging and discharging of energy storage units are controlled by preset rules and thresholds, such as starting the charging and discharging of the energy storage system when the frequency or voltage exceeds a certain threshold. This method is simple and easy to implement, but it has poor adaptability to the dynamic changes of the system and cannot effectively cope with complex operating conditions. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is: how to improve the frequency and voltage stability of the independent grid operation of the photovoltaic storage microgrid, while enhancing the robustness and response speed of the system.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides an energy management control method in an independent networking scenario of a photovoltaic storage microgrid, including:

[0008] Obtaining a first parameter of the microgrid, calculating the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation, and pre-allocating them to each energy storage unit according to a first preset order;

[0009] updating the droop coefficient according to the number of voltage control sources that have not exited operation to obtain a second droop coefficient, and recalculating the active and reactive power regulation amounts according to the second droop coefficient;

[0010] Allocating the active power adjustment amount according to a first allocation rule;

[0011] Setting different target exchange powers according to the SOC interval of the energy storage unit, and adjusting the target exchange power according to the second allocation rule;

[0012] According to the third allocation rule, a specific photovoltaic inverter is selected for switching;

[0013] With respect to the residual active power deviation generated after the photovoltaic inverter is switched on and off, the charging and discharging power of the energy storage unit is adjusted in accordance with a first preset sequence to achieve balance.

[0014] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0015] The calculation of the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation includes:

[0016] According to the frequency deviation and voltage deviation of the microgrid, the adjustment amount of active power and reactive power is calculated in combination with the preset microgrid parameters.

[0017] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0018] The updating of the droop coefficient according to the number of voltage control sources that have not exited operation to obtain the second droop coefficient comprises:

[0019] According to the ratio of the number of currently operating voltage control sources to the total number of system control sources, the value of the droop coefficient is dynamically adjusted to generate a new droop coefficient for further power regulation calculation.

[0020] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0021] The allocating of the active power adjustment amount according to the first allocation rule includes:

[0022] Assume that there are m photovoltaic and energy storage integrated machines and n PCSs; Assume that the maximum charge and discharge power of each energy storage unit is The current real-time power of each energy storage unit is The adjustable potential range of external exchange power of each energy storage unit is Let the set φ m is the set of all optical storage integrated machines, the set φ n For the collection of all PCS, the adjustable potential range of the optical storage integrated machine is Similarly, the adjustable potential range of PCS is

[0023] When ΔP 调节 When it is greater than 0, the charging power of the energy storage unit is increased or the discharging power is reduced;

[0024] when When the light storage integrated machine is used, it can meet the adjustment needs;

[0025] Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is:

[0026]

[0027] For PCS, the allocated power regulation is:

[0028]

[0029] when When φ is 0, the photovoltaic and storage integrated device alone cannot meet the regulation needs, and additional compensation from PCS is required; at this time, all photovoltaic and storage integrated devices are charged at maximum power, that is, the set φ m The power regulation amount obtained by allocating the optical storage integrated device is:

[0030]

[0031] Culling PCS, set φ n The remaining n' PCSs in the set are set to n， , then the set φ n The power adjustment amount allocated to each PCS is:

[0032]

[0033] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0034] The allocating of the active power adjustment amount according to the first allocation rule also includes:

[0035] When ΔP 调节When it is less than or equal to 0, it is necessary to reduce the charging power of the energy storage unit or increase the discharging power;

[0036] when When the light storage integrated machine is used, it can meet the adjustment needs;

[0037] Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is:

[0038]

[0039] For PCS, the allocated power regulation is:

[0040]

[0041] when When φ is 0, the integrated photovoltaic and storage device alone cannot meet the regulation needs and requires additional compensation from the PCS. At this time, all the integrated photovoltaic and storage devices discharge at the maximum power, that is, the aggregate φ m The power regulation amount obtained by allocating the optical storage integrated device is:

[0042]

[0043] Culling PCS, set φ n The remaining n' PCSs in the set are set to n， , then the set φ n The power adjustment amount allocated to each PCS is:

[0044]

[0045] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0046] The adjusting the target switching power according to the second allocation rule includes:

[0047] When the target power of secondary frequency regulation and voltage regulation is allocated When it is not within the target range, adjust the target switching power so that and The deviation value is the smallest; due to the adjustment of the SOC range, an additional power deviation value will be generated:

[0048]

[0049] As a preferred solution for energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid, it includes:

[0050] The selecting a specific photovoltaic inverter for switching according to the third allocation rule includes:

[0051] When ΔP SOC When >0, additional photovoltaic inverters are needed, and several photovoltaic inverters in shutdown state are selected to be put into operation, so that Minimum;

[0052] When ΔP SOC When <0, some photovoltaic inverters need to be removed. Select several photovoltaic inverters to be removed so that Minimum, and

[0053] Assume that the power deviation compensated by the photovoltaic inverter is ΔP solar , then the residual active power deviation of the microgrid system is:

[0054] ΔP′=ΔP SOC -ΔP solar .

[0055] In a second aspect, an embodiment of the present invention provides an energy management control system in an independent networking scenario of a photovoltaic storage microgrid, including:

[0056] A parameter acquisition module is used to obtain a first parameter of the microgrid, calculate the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation, and pre-allocate them to each energy storage unit according to a first preset order;

[0057] A calculation module, used for updating the droop coefficient according to the number of voltage control sources that have not exited operation, obtaining a second droop coefficient, and recalculating the active and reactive power adjustment amounts according to the second droop coefficient;

[0058] A first allocation module, configured to allocate the active power adjustment amount according to a first allocation rule;

[0059] A second allocation module, used to set different target exchange powers according to the SOC interval of the energy storage unit, and adjust the target exchange power according to a second allocation rule;

[0060] A third allocation module is used to select a specific photovoltaic inverter for switching according to a third allocation rule;

[0061] The balancing module is used to adjust the charging and discharging power of the energy storage unit according to a first preset sequence to balance the residual active power deviation generated after the photovoltaic inverter is switched on and off.

[0062] In a third aspect, an embodiment of the present invention provides a computing device, including:

[0063] Memory and processor;

[0064] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the one or more programs are executed by the one or more processors, the one or more processors implement the energy management control method in the independent networking scenario of the photovoltaic energy storage microgrid as described in any embodiment of the present invention.

[0065] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, can implement the energy management control method in the independent networking scenario of the photovoltaic energy storage microgrid.

[0066] Beneficial effects of the present invention: The present invention takes an energy management and control strategy for the independent networking and operation of a photovoltaic and storage microgrid as a research target, and targets the secondary frequency regulation and secondary voltage regulation requirements of the microgrid. According to the frequency difference and voltage difference of the system, the active and reactive regulation required by the system is calculated, and all energy storage units in the microgrid are coordinated and dispatched in order according to a certain priority level to meet the frequency and voltage stability requirements under the independent networking of the microgrid. At the same time, the stable control of the SOC of the microgrid energy storage unit improves the long-term operation capability of the photovoltaic and storage microgrid. The energy management and control strategy for the independent networking and operation of the photovoltaic and storage microgrid proposed in the present invention improves the reliability of local load power supply and enhances the safe and stable operation level of the independent networking of the photovoltaic and storage microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0068] Figure 1 It is an overall flow chart of the energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrids according to the first embodiment of the present invention;

[0069] Figure 2 It is a frequency curve diagram of a photovoltaic and storage microgrid system in a simulation example of an energy management control method in an independent photovoltaic and storage microgrid networking scenario described in the second embodiment of the present invention;

[0070] Figure 3 It is a curve diagram of the effective value of the voltage of the photovoltaic and energy storage microgrid system in the simulation example of the energy management control method in the photovoltaic and energy storage microgrid independent networking scenario described in the second embodiment. DETAILED DESCRIPTION

[0071] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0072] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0073] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0074] Example 1

[0075] Reference Figure 1 , which is the first embodiment of the present invention, and provides an energy management control method in an independent networking scenario of a photovoltaic storage microgrid, including:

[0076] S1: Obtain the first parameter of the microgrid, calculate the active power and reactive power adjustment required for secondary frequency regulation and voltage regulation, and pre-allocate them to each energy storage unit according to a first preset order;

[0077] Specifically, the first parameters of the microgrid are the frequency deviation and voltage deviation of the microgrid, and the first preset order is the order of the photovoltaic storage integrated machine first and then the PCS, where PCS is the abbreviation of Power Conversion System; the control time interval is set to 15 minutes.

[0078] In the embodiment of the present application, calculating the active power and reactive power adjustment amount required for secondary frequency modulation and voltage regulation includes:

[0079] According to the frequency deviation and voltage deviation of the microgrid, the adjustment amount of active power and reactive power is calculated in combination with the preset microgrid parameters.

[0080] Specifically, the active and reactive power regulation amounts are calculated according to the following formulas:

[0081] ΔP 调节 =P_droop×Δf

[0082] ΔQ调节 =Q_droop×ΔV

[0083] Among them, ΔP 调节 is the active power regulation, ΔQ 调节 is the reactive power regulation quantity; Δf and ΔV are the detected frequency deviation and voltage deviation of the microgrid respectively, P_droop is the active power droop coefficient, and Q_droop is the reactive power droop coefficient.

[0084] S2: updating the droop coefficient according to the number of voltage control sources that have not exited operation to obtain a second droop coefficient, and recalculating the active and reactive power regulation amounts according to the second droop coefficient;

[0085] It should be noted that, considering that the VF source may unexpectedly exit during the operation phase of the system, the droop coefficient of the system needs to be updated each time the active and reactive power demands generated by secondary frequency and voltage regulation are calculated; the VF source refers to a power source that adopts the voltage and frequency (Voltage-Frequency, VF) control mode.

[0086] In the embodiment of the present application, the droop coefficient is updated according to the number of voltage control sources that have not exited operation, and the second droop coefficient is obtained including:

[0087] According to the ratio of the number of currently operating voltage control sources to the total number of system control sources, the value of the droop coefficient is dynamically adjusted to generate a new droop coefficient for further power regulation calculation.

[0088] Specifically, the calculation formula of the second droop coefficient is as follows:

[0089] P_droop=freq_coefficient / num_PCS*num_pcs_in

[0090] Q_droop=volt_coefficient / num_PCS*num_pcs_in

[0091] Among them, freq_coefficient is the initial value of the active droop coefficient, volt_coefficient is the initial value of the reactive droop coefficient, num_PCS is the number of PCS in the microgrid system, and num_pcs_in is the number of PCS actually in operation.

[0092] S3: Allocate the active power adjustment amount according to the first allocation rule;

[0093] In an embodiment of the present application, allocating the active power adjustment amount according to the first allocation rule includes:

[0094] Assume that there are m photovoltaic and energy storage integrated machines and n PCSs; Assume that the maximum charge and discharge power of each energy storage unit is The current real-time power of each energy storage unit is The adjustable potential range of external exchange power of each energy storage unit is Let the set φ m is the set of all optical storage integrated machines, the set φ n For the collection of all PCS, the adjustable potential range of the optical storage integrated machine is Similarly, the adjustable potential range of PCS is

[0095] When ΔP 调节 When it is greater than 0, the charging power of the energy storage unit is increased or the discharging power is reduced;

[0096] when When the light storage integrated machine is used, it can meet the adjustment needs;

[0097] Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is:

[0098]

[0099] For PCS, the allocated power regulation is:

[0100]

[0101] when When φ is 0, the photovoltaic and storage integrated device alone cannot meet the regulation needs, and additional compensation from PCS is required; at this time, all photovoltaic and storage integrated devices are charged at maximum power, that is, the set φ m The power regulation amount obtained by allocating the optical storage integrated device is:

[0102]

[0103] Culling PCS, set φ n The remaining n' PCSs in the set are set to n， , then the set φ n The power adjustment amount allocated to each PCS is:

[0104]

[0105] When ΔP 调节 When it is less than or equal to 0, it is necessary to reduce the charging power of the energy storage unit or increase the discharging power;

[0106] when When the light storage integrated machine is used, it can meet the adjustment needs;

[0107] Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is:

[0108]

[0109] For PCS, the allocated power regulation is:

[0110]

[0111] when When φ is 0, the integrated photovoltaic and storage device alone cannot meet the regulation needs and requires additional compensation from the PCS. At this time, all the integrated photovoltaic and storage devices discharge at the maximum power, that is, the aggregate φ m The power regulation amount obtained by allocating the optical storage integrated device is:

[0112]

[0113] Culling PCS, set φ n The remaining n' PCSs in the set are set to n， , then the set φ n The power adjustment amount allocated to each PCS is:

[0114]

[0115] It should be noted that the present invention uses the active power distribution demand caused by secondary frequency regulation as an example for explanation, and the reactive power distribution demand caused by secondary voltage regulation is similar. When there are multiple energy storage units in the microgrid, the active power adjustment amount needs to be allocated to each energy storage unit. When allocating and adjusting power, the priority of the photovoltaic storage integrated machine is higher than that of the PCS; considering the impact of frequent charging and discharging on battery performance and life, after considering the priority, for the same type of energy storage units, their adjustment tasks are allocated as much as possible so that their charging and discharging power is as consistent as possible.

[0116] S4: setting different target exchange powers according to the SOC interval of the energy storage unit, and adjusting the target exchange power according to the second allocation rule;

[0117] It should be noted that to achieve the stable control of the SOC of the energy storage unit in the microgrid, different target intervals of exchange power are set for the energy storage unit according to different SOC intervals. When the SOC is too high or too low, according to the set target interval of exchange power, the value with the smallest deviation from the regulation amount allocated after secondary frequency modulation is taken as the target power, so that the SOC returns to the target interval. Considering the charging and discharging power of the energy storage unit, the control time interval is set to 5 minutes.

[0118] To ensure the safe and stable operation of the independent grid-forming mode of the photovoltaic-storage microgrid, the power required for system operation is mainly provided by the photovoltaic inverter during independent grid formation, and the power deviation value is balanced by the PQ source (photovoltaic-storage integrated machine) and the VF source (PCS); during the independent grid-forming operation stage, the PQ source and the VF source are尽可能 kept at a relatively high level of SOC; when adjusting the power, the PQ source is adjusted first. Therefore, the target exchange power of each energy storage unit at different SOCs is set as follows:

[0119] PCS (VF source):

[0120] 0.5 < SOC < 0.75, P = 50 (hoping that the VF source slowly returns to a relatively high level of SOC)

[0121] 0.75 < SOC < 0.8, Pmin < P < 0.5 * Pmax

[0122] 0.8 < SOC < 1, Pmin < P < -50 (to avoid too high SOC of the VF source)

[0123] 0 < SOC < 0.5, 50 < P < Pmax

[0124] Photovoltaic-storage integrated machine (PQ source)

[0125] 0 < SOC < 0.8, 100 < P < Pmax (hoping that the PQ source stores electricity as much as possible)

[0126] 0.8 < SOC < 0.95, Pmin < P < 0.5 * Pmax

[0127] 0.95 < SOC < 1, Pmin < P < -50

[0128] In the embodiment of the present application, adjusting the target exchange power according to the second distribution rule includes:

[0129] When the target power allocated by secondary frequency modulation and voltage regulation is not within the target interval, the target exchange power is adjusted so that the within the target interval and the deviation value is the smallest; due to the adjustment of the SOC range, an additional power deviation value will be generated:

[0130]

[0131] S5: According to the third allocation rule, a specific photovoltaic inverter is selected for switching;

[0132] It should be noted that for the active power deviation value after adjustment and pre-allocation of the photovoltaic storage microgrid energy management system, power balance is achieved as much as possible by partially cutting off or putting into use the photovoltaic inverter, that is, selecting specific photovoltaic inverters for switching on to make up for the active power deviation value, and setting the control time interval to 5 minutes.

[0133] In the embodiment of the present application, according to the third allocation rule, selecting a specific photovoltaic inverter for switching includes:

[0134] When ΔP SOC When >0, additional photovoltaic inverters are needed, and several photovoltaic inverters in shutdown state are selected to be put into operation, so that Minimum.

[0135] When ΔP SOC When <0, some photovoltaic inverters need to be removed. Select several photovoltaic inverters to be removed so that Minimum, and

[0136] Assume that the power deviation compensated by the photovoltaic inverter is ΔP solar , then the residual active power deviation of the microgrid system is:

[0137] ΔP′=ΔP SOC -ΔP solar

[0138] S6: With respect to the residual active power deviation generated after the photovoltaic inverter is switched on and off, the charging and discharging power of the energy storage unit is adjusted according to a first preset sequence to balance it.

[0139] It should be noted that the active power deviation value after the photovoltaic inverter is switched on / off and after pre-distribution is balanced by adjusting the charging and discharging power of the energy storage unit, and is pre-distributed to each energy storage unit in the order of photovoltaic storage unit first and then PCS, and the control time interval is set to 5 minutes; ΔP' is distributed to each energy storage unit in the order of PQ source first and then VF source.

[0140] The above is a schematic scheme of the energy management control method in the scenario of independent networking of the photovoltaic storage microgrid of this embodiment. It should be noted that the technical scheme of the energy management control system in the scenario of independent networking of the photovoltaic storage microgrid and the technical scheme of the energy management control method in the scenario of independent networking of the photovoltaic storage microgrid above belong to the same concept. For the details not described in detail in the technical scheme of the energy management control system in the scenario of independent networking of the photovoltaic storage microgrid in this embodiment, please refer to the description of the technical scheme of the energy management control method in the scenario of independent networking of the photovoltaic storage microgrid above.

[0141] In this embodiment, the energy management and control system in the scenario of independent networking of the photovoltaic storage microgrid includes:

[0142] A parameter acquisition module is used to obtain a first parameter of the microgrid, calculate the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation, and pre-allocate them to each energy storage unit according to a first preset order;

[0143] A calculation module, used for updating the droop coefficient according to the number of voltage control sources that have not exited operation, obtaining a second droop coefficient, and recalculating the active and reactive power adjustment amounts according to the second droop coefficient;

[0144] A first allocation module, configured to allocate the active power adjustment amount according to a first allocation rule;

[0145] A second allocation module, used to set different target exchange powers according to the SOC interval of the energy storage unit, and adjust the target exchange power according to a second allocation rule;

[0146] A third allocation module is used to select a specific photovoltaic inverter for switching according to a third allocation rule;

[0147] The balancing module is used to adjust the charging and discharging power of the energy storage unit according to a first preset sequence to balance the residual active power deviation generated after the photovoltaic inverter is switched on and off.

[0148] This embodiment also provides a computing device, which is applicable to the energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrids, including:

[0149] Memory and processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement the energy management control method in the independent networking scenario of the photovoltaic storage microgrid as proposed in the above embodiment.

[0150] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the energy management control method in the independent networking scenario of the photovoltaic energy storage microgrid proposed in the above embodiment is implemented.

[0151] The storage medium proposed in this embodiment and the energy management control method in the independent networking scenario of the photovoltaic storage microgrid proposed in the above embodiment belong to the same inventive concept. The technical details not described in detail in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0152] Example 2

[0153] Reference Figure 2-Figure 3 , which is an embodiment of the present invention, provides an energy management control method in an independent networking scenario of a photovoltaic energy storage microgrid. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through simulation experiments.

[0154] like Figure 2 As shown in the figure, the system frequency curve recorded by the energy management system is the independent network operation of the photovoltaic storage microgrid. Figure 3 As shown in the figure, the system voltage effective value curve recorded by the energy management system during the independent networking operation of the photovoltaic storage microgrid is shown. The simulation experiment results show that when the photovoltaic storage microgrid is independently networked, the frequency operation range of the microgrid under the impact of active and reactive loads is 49.9-50.1Hz, the voltage operation range is 95.88%-101.47%Un, the frequency control accuracy of the secondary frequency regulation system is 0.1Hz, and the voltage control accuracy of the secondary voltage regulation system is 1%Un. The experimental results verify the energy management control strategy for the independent networking operation of the photovoltaic storage microgrid proposed in the present invention. Through the coordinated control of source / storage / load, the self-balancing of the internal energy of the microgrid is achieved, the reliability of local load power supply is improved, and the safe and stable operation level of the independent networking of the photovoltaic storage microgrid is enhanced.

[0155] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An energy management control method for independent networking of photovoltaic and energy storage microgrids. It is characterized in that include: Obtaining a first parameter of the microgrid, calculating the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation, and pre-allocating them to each energy storage unit according to a first preset order; updating the droop coefficient according to the number of voltage control sources that have not exited operation to obtain a second droop coefficient, and recalculating the active and reactive power regulation amounts according to the second droop coefficient; Allocating the active power adjustment amount according to a first allocation rule; Setting different target exchange powers according to the SOC interval of the energy storage unit, and adjusting the target exchange power according to the second allocation rule; According to the third allocation rule, a specific photovoltaic inverter is selected for switching; With respect to the residual active power deviation generated after the photovoltaic inverter is switched on and off, the charging and discharging power of the energy storage unit is adjusted in accordance with a first preset sequence to achieve balance.

2. The energy management control method in the scenario of independent networking of photovoltaic storage microgrid as claimed in claim 1, It is characterized in that The calculation of the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation includes: According to the frequency deviation and voltage deviation of the microgrid, the adjustment amount of active power and reactive power is calculated in combination with the preset microgrid parameters.

3. The energy management control method in the scenario of independent networking of photovoltaic energy storage microgrid as claimed in claim 2, It is characterized in that The updating of the droop coefficient according to the number of voltage control sources that have not exited operation to obtain the second droop coefficient comprises: According to the ratio of the number of currently operating voltage control sources to the total number of system control sources, the value of the droop coefficient is dynamically adjusted to generate a new droop coefficient for further power regulation calculation.

4. The energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid as claimed in claim 3, It is characterized in that The allocating of the active power adjustment amount according to the first allocation rule includes: Assume that there are m photovoltaic and energy storage integrated machines and n PCSs; Assume that the maximum charge and discharge power of each energy storage unit is The current real-time power of each energy storage unit is The adjustable potential range of external exchange power of each energy storage unit is Let the set φ m is the set of all optical storage integrated machines, the set φ n For the collection of all PCS, the adjustable potential range of the optical storage integrated machine is Similarly, the adjustable potential range of PCS is When ΔP 调节 When it is greater than 0, the charging power of the energy storage unit is increased or the discharging power is reduced; when When the light storage integrated machine is used, it can meet the adjustment needs; Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is: For PCS, the allocated power regulation is: when When φ is 0, the photovoltaic and storage integrated device alone cannot meet the regulation needs, and additional compensation from PCS is required; at this time, all photovoltaic and storage integrated devices are charged at maximum power, that is, the set φ m The power regulation amount obtained by allocating the optical storage integrated device is: Culling PCS, set φ n The remaining n' PCSs in the set are set to n’ , then the set φ n The power adjustment amount allocated to each PCS is:

5. The energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid as claimed in claim 4, It is characterized in that The allocating of the active power adjustment amount according to the first allocation rule also includes: When ΔP 调节 When it is less than or equal to 0, it is necessary to reduce the charging power of the energy storage unit or increase the discharging power; when When the light storage integrated machine is used, it can meet the adjustment needs; Culling The integrated optical storage machine, integrating φ m The remaining m' optical storage integrated machines in the system are set as the set φ m， , then the set φ m The power adjustment amount allocated to each integrated optical storage device is: For PCS, the allocated power regulation is: when When φ is 0, the integrated photovoltaic and storage device alone cannot meet the regulation needs and requires additional compensation from the PCS. At this time, all the integrated photovoltaic and storage devices discharge at the maximum power, that is, the aggregate φ m The power regulation amount obtained by allocating the optical storage integrated device is: Culling PCS, set φ n The remaining n' PCSs in the set are set to n’ , then the set φ n The power adjustment amount allocated to each PCS is:

6. The energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid as claimed in claim 5, It is characterized in that The adjusting the target switching power according to the second allocation rule includes: When the target power of secondary frequency regulation and voltage regulation is allocated When it is not within the target range, adjust the target switching power so that and The deviation value is the smallest; due to the adjustment of the SOC range, an additional power deviation value will be generated:

7. The energy management control method in the scenario of independent networking of photovoltaic and energy storage microgrid as claimed in claim 6, It is characterized in that The selecting a specific photovoltaic inverter for switching according to the third allocation rule includes: When ΔP SOC When >0, additional photovoltaic inverters are needed, and several photovoltaic inverters in shutdown state are selected to be put into operation, so that Minimum; When ΔP SOC When <0, some photovoltaic inverters need to be removed. Select several photovoltaic inverters to be removed so that Minimum, and Assume that the power deviation compensated by the photovoltaic inverter is ΔP solar , then the residual active power deviation of the microgrid system is: ΔP′=ΔP SOC -ΔP solar 。 8. A system using the energy management control method in an independent networking scenario of a photovoltaic energy storage microgrid as described in any one of claims 1 to 7, It is characterized in that include: A parameter acquisition module is used to obtain a first parameter of the microgrid, calculate the active power and reactive power adjustment amount required for secondary frequency regulation and voltage regulation, and pre-allocate them to each energy storage unit according to a first preset order; A calculation module, used for updating the droop coefficient according to the number of voltage control sources that have not exited operation, obtaining a second droop coefficient, and recalculating the active and reactive power adjustment amounts according to the second droop coefficient; A first allocation module, configured to allocate the active power adjustment amount according to a first allocation rule; A second allocation module, used to set different target exchange powers according to the SOC interval of the energy storage unit, and adjust the target exchange power according to a second allocation rule; A third allocation module is used to select a specific photovoltaic inverter for switching according to a third allocation rule; The balancing module is used to adjust the charging and discharging power of the energy storage unit according to a first preset sequence to balance the residual active power deviation generated after the photovoltaic inverter is switched on and off.

9. A computing device, include: Memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the energy management control method in the independent networking scenario of the photovoltaic energy storage microgrid are implemented as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the energy management control method in the independent networking scenario of a photovoltaic energy storage microgrid as described in any one of claims 1 to 7.

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