A coordinated control system for energy storage and power grid based on photovoltaic priority energy supply

Abstract

This application discloses a coordinated control system for energy storage and power grid based on photovoltaic priority energy supply, which relates to the field of power system dispatch automation technology. The method includes: through real-time collection of photovoltaic module output power, energy storage unit charge state value and load power demand, based on a preset photovoltaic priority energy supply strategy, dynamically calculating the power distribution weight of photovoltaic and energy storage, and determining the target output power of photovoltaic modules and energy storage units; when both photovoltaic and energy storage cannot meet the load demand, automatically judging and triggering grid access control to ensure the continuity and stability of power supply. This solves the problems of the prior art photovoltaic storage integrated system in the power dispatch process, such as the lack of dynamic reflection of the photovoltaic priority energy supply principle, inflexible power distribution method, delayed grid access response, and lack of adaptive regulation to dynamically adjust the output current according to the real-time operating status.

Description

Technical Field

[0001] The present application relates to the technical field of power system dispatching automation, and in particular to a storage and power grid coordination control system based on photovoltaic priority energy supply. Background Art

[0002] With the large-scale integration of renewable energy, photovoltaic power generation has become an important form of clean energy in the power system. However, due to the inherent volatility and intermittent nature of photovoltaic power generation, it is difficult to stably match the real-time power demands of user loads. Energy storage systems are usually required to achieve dynamic energy balance and regulation, thereby building an integrated energy supply system that combines photovoltaics and energy storage to improve the utilization efficiency of photovoltaic energy and the stability of system operation. In scenarios such as user-side and microgrids, the coordinated operation of photovoltaics and energy storage places higher demands on power allocation strategies. Especially when both have power supply capabilities, how to prioritize the use of photovoltaic resources and reasonably control the response of energy storage is a key factor affecting system efficiency and energy storage life.

[0003] Most existing PV-storage system scheduling methods use fixed priorities or simple threshold judgment strategies for power allocation. These methods lack a joint assessment of the real-time output capacity of photovoltaics and the current state of charge of energy storage, and fail to fully reflect the principle of photovoltaic-first energy supply. For example, even when photovoltaics have strong output capacity, some systems still frequently call on energy storage units for discharge, which neither maximizes the utilization of clean energy nor accelerates the charge and discharge cycle of energy storage equipment, affecting its service life. Furthermore, traditional solutions typically do not implement a dynamic weight allocation mechanism in multi-path energy supply scenarios, making it impossible to intelligently calculate the target output of photovoltaics and energy storage based on current power capabilities, resulting in unstable and uneconomical energy supply solutions.

[0004] Therefore, it is urgent to propose a method and device for coordinated control of energy storage and power grid based on the photovoltaic priority energy supply strategy. This method can dynamically judge the feasibility of each current energy supply path according to information such as photovoltaic real-time power, energy storage charge state value and load power demand, and realize intelligent allocation of target power output by calculating the weight coefficient of photovoltaic and energy storage. Under the premise of meeting the reliability of load energy supply, photovoltaic resources are used first, energy storage units are dispatched reasonably, and grid energy replenishment is connected according to actual needs, thereby improving the overall energy efficiency and operating life of the photovoltaic storage system. Summary of the Invention

[0005] The purpose of this application is to provide a coordinated energy storage and grid control system based on photovoltaic priority energy supply. This system aims to address the problems of existing photovoltaic-storage integrated systems in the power dispatch process, such as the lack of dynamic implementation of the photovoltaic priority energy supply principle, inflexible power allocation methods, delayed grid access response, and lack of adaptive regulation to dynamically adjust output current based on real-time operating conditions.

[0006] In view of the above technical problems, the present application provides a storage and grid coordination control system based on photovoltaic priority energy supply.

[0007] In a first aspect of an embodiment of the present application, there is provided a storage and grid coordinated control system based on photovoltaic priority energy supply, the system comprising:

[0008] A data acquisition module, the data acquisition module is used to monitor the photovoltaic real-time power of the photovoltaic component in real time through the photovoltaic inverter, obtain the charge state value of the energy storage unit through the battery management system, the charge state value is used to indicate the current percentage of the energy storage unit's rated capacity, and monitor the load power demand on the load side in real time through the current sensor and the voltage sensor; a power distribution calculation module, the power distribution calculation module is used to dynamically calculate the photovoltaic power weight coefficient and the energy storage power weight coefficient based on the preset photovoltaic priority energy supply strategy, using the collected photovoltaic real-time power, charge state value and load power demand, to obtain the photovoltaic component target output power and the energy storage unit target charge and discharge power as the current power distribution scheme; a dynamic power adjustment module, the dynamic power adjustment module is used to adjust the photovoltaic component target output power and the energy storage unit target according to the real-time changes in the load power demand. The target charge and discharge power is dynamically adjusted, and the power distribution path is optimized based on the current supply and demand status to obtain a revised power distribution plan, wherein the power distribution path is used to indicate the power supply priority and power distribution ratio of the photovoltaic components and the energy storage unit to the load; a coordination output module, wherein the coordination output module is used to generate a coordination output control instruction including the control parameters of the target output power of the photovoltaic components and the control parameters of the target charge and discharge power of the energy storage unit according to the revised power distribution plan, and send the coordinated output control instruction to the photovoltaic components and the energy storage unit to coordinate the execution of the joint power output in accordance with the revised power distribution plan; a grid access module, wherein the grid access module is used to generate a grid access instruction for controlling the grid connection if the real-time photovoltaic power is lower than the load power demand and the state of charge value is lower than the set threshold, and send the access instruction to the grid for triggering the grid energy supply behavior.

[0009] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0010] The photovoltaic real-time power of the photovoltaic module is monitored in real time through the photovoltaic inverter, and the charge state value of the energy storage unit is obtained through the battery management system. The charge state value is used to indicate the percentage of the current energy storage unit power to its rated capacity, and the load power demand on the load side is monitored in real time through the current sensor and the voltage sensor; based on the preset photovoltaic priority energy supply strategy, the photovoltaic power weight coefficient and the energy storage power weight coefficient are dynamically calculated using the collected photovoltaic real-time power, charge state value and load power demand, and the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are obtained as the current power allocation scheme; according to the real-time changes in the load power demand, the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are dynamically adjusted. , and optimize the power distribution path based on the current supply and demand status to obtain a revised power distribution plan, wherein the power distribution path is used to indicate the power supply priority and power distribution ratio of the photovoltaic components and energy storage units to the load; based on the revised power distribution plan, a coordinated output control instruction is generated containing the control parameters of the target output power of the photovoltaic components and the control parameters of the target charge and discharge power of the energy storage unit, and sent to the photovoltaic components and energy storage units to coordinate the execution of the joint power output in accordance with the revised power distribution plan; if the photovoltaic real-time power is lower than the load power demand and the state of charge value is lower than the set threshold, a grid access instruction for controlling the grid connection is generated, and the access instruction is sent to the grid for triggering the grid power supply behavior. This solves the problems in the prior art of the photovoltaic storage integrated system in the power scheduling process, such as the lack of dynamic reflection of the photovoltaic priority power supply principle, the inflexible power distribution method, the delayed grid access response, and the lack of adaptive regulation for dynamically adjusting the output current according to the real-time operating status.

[0011] The above description is only an overview of the technical solution of the present application. In order to more clearly illustrate the technical means of the present application and to implement it in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the accompanying drawings of the embodiments of the present disclosure are briefly introduced below. Flowcharts are used in this application to illustrate the operations performed by the systems according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed in precise order. Instead, various steps may be processed in reverse order or simultaneously as needed. Furthermore, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0013] Figure 1 A schematic diagram of the structure of a coordinated control system for energy storage and power grid based on photovoltaic priority energy supply provided in an embodiment of the present application;

[0014] Description of the accompanying drawings: data acquisition module 10 , power allocation calculation module 20 , dynamic power adjustment module 30 , coordination output module 40 , grid access module 50 . DETAILED DESCRIPTION

[0015] This application provides a storage and grid coordination control system based on photovoltaic priority energy supply, which solves the problems in the existing technology of photovoltaic storage integrated system in the power scheduling process, such as the lack of dynamic reflection of the photovoltaic priority energy supply principle, inflexible power distribution method, delayed grid access response, and lack of adaptive regulation of output current dynamically adjusted according to real-time operating status.

[0016] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0017] It should be noted that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or modules that are not clearly listed or are inherent to these processes, methods, products or devices.

[0018] Example 1, as Figure 1 As shown, the present application provides a storage and grid coordinated control system based on photovoltaic priority energy supply, wherein the system includes:

[0019] The data acquisition module 10 is used to monitor the real-time photovoltaic power of the photovoltaic module through the photovoltaic inverter in real time, obtain the charge state value of the energy storage unit through the battery management system, and the charge state value is used to indicate the percentage of the current energy storage unit power to its rated capacity, and monitor the load power demand on the load side in real time through the current sensor and the voltage sensor.

[0020] Specifically, the system monitors the real-time photovoltaic power of photovoltaic modules through photovoltaic inverters, obtains the current state of charge (SOC) of the energy storage unit through the battery management system (BMS), and obtains the instantaneous power demand on the load side through the current sensor and voltage sensor installed on the load branch. The above three parameters serve as the basic input data for energy management scheduling, and the collection frequency is set according to the real-time requirements of the system to ensure the timeliness and accuracy of the power allocation response.

[0021] The power allocation calculation module 20 is used to dynamically calculate the photovoltaic power weight coefficient and the energy storage power weight coefficient based on the preset photovoltaic priority energy supply strategy, using the collected photovoltaic real-time power, charge state value and load power demand, to obtain the target output power of the photovoltaic component and the target charging and discharging power of the energy storage unit as the current power allocation plan.

[0022] Specifically, to implement a power allocation strategy based on PV-first energy supply, the system first collects the current PV module output power, the energy storage unit's state of charge (SOC), and the load's power demand as input data. The system then makes judgments and controls based on the preset PV-first energy supply rules: When the PV module's current output power is greater than or equal to the load's power demand, the system assumes that PV has primary power supply capability and sets the PV power allocation weight to 1 and the energy storage power allocation weight to 0. At this point, all loads are covered by PV power. When PV output is insufficient and the energy storage unit's SOC is above the system's set minimum discharge threshold, the system assumes that the energy storage has discharge capability and sets the PV weight to 0 and the energy storage weight to 1. The load power is then provided by the energy storage. When PV output is insufficient to independently meet the load but still exceeds the set minimum effective output threshold, and the energy storage's SOC is also above the minimum discharge threshold, indicating that both PV and energy storage can contribute to power supply, the system then estimates the energy storage unit's dischargeable power based on the energy storage unit's rated capacity, battery voltage, current SOC, discharge efficiency, and discharge safety threshold. After obtaining the real-time PV output power and the energy storage's dischargeable power, the system calculates the power supply weights for PV and energy storage, respectively, based on their respective available power ratios. This weighting serves as the basis for power allocation, ensuring PV priority. The calculated weights are used to further determine the target output power of the PV modules and the target output power of the energy storage units for the current cycle, forming a complete power allocation plan. This method offers the advantage of dynamically adjusting the power supply ratio between PV and energy storage in real time, ensuring system power stability while maximizing PV resource utilization and reducing frequent charging and discharging of energy storage, helping to extend the life of the energy storage and improve overall system energy efficiency.

[0023] Furthermore, the preset photovoltaic priority energy supply strategy uses the collected photovoltaic real-time power, state of charge value and load power demand to dynamically calculate the photovoltaic power weight coefficient and the energy storage power weight coefficient, and obtain the photovoltaic module target output power and the energy storage unit target charge and discharge power as the current power allocation plan, including:

[0024] Based on the preset photovoltaic priority energy supply strategy, the photovoltaic power weight coefficient and energy storage power weight coefficient for power distribution are obtained. Combined with the currently collected load power demand, the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are calculated respectively. The calculation formula is as follows:

[0025] The target output power formula of photovoltaic modules is:

[0026] = × ;

[0027] in is the load power requirement, is the photovoltaic power weight coefficient, The target output power of the photovoltaic module;

[0028] The target charging and discharging power formula of the energy storage unit is:

[0029] = × ;

[0030] in is the load power requirement, is the energy storage power weight coefficient, The target charge and discharge power of the energy storage unit. A positive value indicates discharge, and a negative value indicates charge.

[0031] Furthermore, the preset photovoltaic priority energy supply strategy includes:

[0032] If the photovoltaic real-time power is not less than the load power demand, it is determined that the photovoltaic module has the main supply capability, and the photovoltaic power weight coefficient is set. =1, Energy storage power weight coefficient =0, the output power of the energy storage unit is not determined at all;

[0033] If the photovoltaic real-time power is lower than the load power demand, and if the state of charge value is not lower than the energy storage discharge lower limit threshold set by the system, it is determined that the energy storage unit has discharge capacity and the photovoltaic power weight coefficient is set. =0, energy storage power weight coefficient =1;

[0034] If the photovoltaic real-time power is not less than the set photovoltaic minimum effective output threshold, and the state of charge value is not less than the energy storage discharge lower limit threshold, and the dischargeable power calculated based on the current state of charge value, battery rated capacity, battery rated voltage and discharge efficiency is greater than zero, then it is determined that the photovoltaic module has the main power supply capability and the energy storage unit has the discharge capability;

[0035] The calculation formula is as follows:

[0036] ；

[0037] ；

[0038] in, is the photovoltaic real-time power, is the estimated discharge power of the energy storage unit, is the photovoltaic power weight coefficient, is the energy storage power weight coefficient, satisfying + =1;

[0039] when When it increases, the Corresponding increase, The power is reduced accordingly, thereby allocating power to the photovoltaic module output first;

[0040] The estimated dischargeable power of the energy storage unit is calculated as follows:

[0041] ；

[0042] in, is the rated capacity of the battery, is the rated voltage of the battery, is the current state of charge value of the energy storage unit, is the lower limit of the state of charge threshold range, is the discharge efficiency of the battery, is the estimated discharge power of the energy storage unit;

[0043] The rated capacity of the battery is a device parameter preset in the system configuration, which is read and stored during the system deployment phase. The rated voltage of the battery is the nominal value provided by the battery at the factory. The discharge efficiency of the battery is preset by the system based on the model and characteristics of the selected energy storage unit.

[0044] Specifically, to implement a power scheduling strategy based on photovoltaic priority energy supply, the system first collects the current photovoltaic real-time power, the state of charge (SOC) of the energy storage unit, and the power demand of the current load, and dynamically calculates the photovoltaic power weight coefficient and the energy storage power weight coefficient based on this, thereby obtaining the target output power of the photovoltaic module and the target charging and discharging power of the energy storage unit. The system first allocates energy supply responsibilities based on a preset photovoltaic priority judgment logic: When the real-time photovoltaic power is greater than or equal to the load power demand, the system determines that the PV modules have independent primary power supply capability. In this case, the photovoltaic power weight is set to 1 and the energy storage power weight is set to 0, and the PV modules directly provide full power. If the real-time photovoltaic power is insufficient to meet the load, but the energy storage unit's state of charge is above the preset minimum discharge threshold, the system determines that the energy storage has discharge capability, setting the energy storage weight to 1 and the photovoltaic weight to 0, and the energy storage provides power entirely. If the photovoltaic output is insufficient but still above the minimum effective output threshold, and the energy storage also has discharge capability (i.e., the state of charge is above the threshold and the estimated dischargeable power is greater than 0), the system determines that both photovoltaic and energy storage can provide power. In this case, the weighted ratio of the real-time photovoltaic power to the estimated dischargeable power of the energy storage is calculated to determine the photovoltaic and energy storage supply weight coefficients. The dischargeable power of the energy storage unit is estimated based on parameters such as the battery's rated capacity, voltage, current state of charge, minimum discharge threshold, and discharge efficiency. Ultimately, the system multiplies the calculated PV power weight coefficient by the load power demand to determine the target PV panel output power. Simultaneously, the energy storage weight coefficient is multiplied by the load power demand to determine the target power of the energy storage unit (positive values ​​indicate discharge, negative values ​​indicate charge). This process ensures that PV energy is prioritized while meeting the load, while also rationally scheduling energy storage resources, improving PV efficiency, extending the lifespan of energy storage, and ensuring the overall system's energy supply stability and cost-effectiveness.

[0045] A dynamic power adjustment module 30 is configured to dynamically adjust the target output power of the photovoltaic modules and the target charge and discharge power of the energy storage units according to real-time changes in the load power demand, and optimize the power allocation path based on the current supply and demand status to obtain a revised power allocation plan. The power allocation path is configured to indicate the power supply priority and power allocation ratio of the photovoltaic modules and the energy storage units to the load;

[0046] Further, including:

[0047] Calculate the average value of the load power demand in the current scheduling period and differentiate it from the average value of the load power demand in the previous scheduling period to obtain a load power change value;

[0048] When the load power demand increases, that is, the load power change value is positive, and the photovoltaic real-time power is less than the photovoltaic maximum output power threshold set by the system, it is determined that the photovoltaic module has surplus power generation capacity. Based on the minimum value between the load power change value and the surplus power generation capacity, the target output power of the photovoltaic module is increased, and the energy storage unit maintains the current output state;

[0049] When the load power change value is positive, and the photovoltaic real-time power output has reached the photovoltaic maximum output power threshold set by the system, and the state of charge value of the energy storage unit is higher than the discharge lower limit threshold set by the system, and the estimated dischargeable power of the energy storage unit is greater than zero, the discharge portion of the target charge and discharge power of the energy storage unit is increased to make up for the load power difference;

[0050] When the load power demand decreases, that is, the load power change value is negative, the discharge portion of the target charge and discharge power of the energy storage unit is adjusted downward to avoid over-discharge while maintaining stable output of the photovoltaic module;

[0051] Based on the available output power of the photovoltaic module and the discharge capacity of the energy storage unit, combined with the current load power demand, the priority of the photovoltaic energy supply path and the energy storage energy supply path is determined, and the main supply path is dynamically switched to achieve adjustment of the power distribution path and reconstruction of the energy flow direction. The available output power of the photovoltaic module is the maximum output power calculated based on the current light intensity and the maximum output power limit set by the system. The discharge capacity of the energy storage unit is the maximum discharge power that can be released to the load when its current state of charge value is higher than the lower discharge limit threshold set by the system;

[0052] The dynamically adjusted target output power of the photovoltaic modules and the target charging and discharging power of the energy storage unit constitute a revised power allocation plan.

[0053] Specifically, to achieve adaptive regulation of energy distribution, the system dynamically adjusts the calculated target output power of photovoltaic modules and the target charge and discharge power of energy storage units based on the real-time changes in load power demand. On this basis, it optimizes the power distribution path based on the current supply and demand status to form a revised power distribution plan. Among them, the power distribution path indicates the priority relationship between photovoltaic modules and energy storage units during the power supply process and their corresponding power distribution ratio. Specifically, the system first calculates the average load power demand in the current scheduling cycle and differs it from the average value of the previous scheduling cycle to obtain the load power change value. If the load power change value is positive, indicating that the load power demand is increasing, and the current photovoltaic real-time power is less than the photovoltaic maximum output power threshold set by the system, the photovoltaic module is considered to have surplus power generation capacity. The system will increase the target output power of the photovoltaic module based on the smaller value of the load power change value and the surplus power generation capacity, and the energy storage unit will maintain its current output unchanged; if the load power change value is positive and the photovoltaic is outputting at full load, and the energy storage unit's state of charge value is higher than the discharge lower limit threshold, and the dischargeable power is greater than zero, the system will determine that the energy storage has energy replenishment capability and increase the target discharge power of the energy storage unit to compensate for the load power difference; if the load power change value is negative, indicating that the load demand is decreasing, the system will decrease the target discharge power of the energy storage unit to prevent excessive discharge of the battery, while keeping the photovoltaic module output stable. Based on the above, the system comprehensively determines the availability and priority of PV and energy storage paths based on the maximum available output power of the PV panels under current lighting conditions (determined by both light intensity and inverter limitations) and the maximum discharge power of the energy storage unit at the current state of charge (calculated only when the state of charge is above a set lower threshold). It then dynamically selects the primary supply path, reconfiguring power distribution paths and optimizing energy flows. Ultimately, the adjusted PV panel target output power and the target charge and discharge power of the energy storage unit are combined into a revised power allocation plan, which guides energy supply execution within the current scheduling cycle.

[0054] A coordinated output module 40 is used to generate a coordinated output control instruction including control parameters for the target output power of the photovoltaic module and control parameters for the target charge and discharge power of the energy storage unit based on the revised power allocation scheme, and send the coordinated output control instruction to the photovoltaic module and the energy storage unit to coordinate the execution of the joint power output that complies with the revised power allocation scheme.

[0055] Specifically, after obtaining the revised power allocation plan, the system uses the target output power of the photovoltaic modules and the target charge and discharge power of the energy storage unit as the control basis, and generates a coordinated output control instruction containing these two power control parameters. The target output power of the photovoltaic modules is calculated based on the product of the photovoltaic power weight coefficient and the current load power demand, while the target charge and discharge power of the energy storage unit is calculated based on the product of the energy storage power weight coefficient and the current load power demand. The calculation basis of the above two weight coefficients includes the currently collected operating status parameters such as the photovoltaic real-time power, the energy storage charge state value, the battery rated capacity, the battery rated voltage and the discharge efficiency, to ensure the rationality and responsiveness of the power allocation. The generated control instructions are sent to the photovoltaic output control terminal and the energy storage control execution terminal respectively through communication, driving the two to synchronously execute power output according to the revised power allocation plan, thereby achieving a joint response to the load power demand and improving the coordination of system operation and the reliability of power supply.

[0056] Further, including:

[0057] Extract the target output power value of the photovoltaic module from the modified power allocation scheme and the target charge and discharge power value of the energy storage unit ;

[0058] Set the PV module target current correction coefficient that is dynamically adjusted according to the system operating status Correction coefficient of target current of energy storage unit ;

[0059] The output voltage value of the current photovoltaic module side is obtained by collecting the real-time detection value of the DC side voltage of the photovoltaic inverter , based on the target output power value of the photovoltaic module The current output voltage value of the photovoltaic module side , calculate the target output current ,

[0060] The calculation formula is: ;

[0061] in, is the target current correction coefficient of the photovoltaic module, and its value range is 0.8~1.2;

[0062] The target output power value of the photovoltaic module is input into the maximum power point tracking controller MPPT, and the target voltage value is dynamically adjusted using the voltage disturbance method, combined with the target output current value , generating photovoltaic inverter control parameters including target voltage and target current as control parameters of target output power of photovoltaic modules;

[0063] Determine the target charge and discharge power value of the energy storage unit to determine the positive and negative signs of the current energy storage unit control mode, and generate control parameters for the target charge and discharge power of the energy storage unit based on the control mode, wherein the control parameters for the target charge and discharge power of the energy storage unit include the target current after the limit processing, the safety threshold judgment result, and the output control mode;

[0064] Encapsulating the control parameters of the target output power of the photovoltaic module and the control parameters of the target charge and discharge power of the energy storage unit into a coordinated output control instruction, wherein the coordinated output control instruction is used to adjust the output current of the photovoltaic inverter and control the charge and discharge state of the energy storage converter;

[0065] The photovoltaic inverter and the energy storage converter are driven according to the coordinated output control instruction to coordinate and execute a joint power output that complies with the revised power allocation scheme.

[0066] Furthermore, the target charge and discharge power value of the energy storage unit is determined to determine the current control mode of the energy storage unit, and generate control parameters of the target charge and discharge power of the energy storage unit based on the control mode, including:

[0067] When the target charge and discharge power value of the energy storage unit >0, the power control mode is determined to be discharge mode, and the target current calculation method is as follows Calculate target discharge current;

[0068] When the target charge and discharge power value of the energy storage unit <0, the power control mode is determined to be charging mode, and the target current calculation method is as follows = - Calculate the target charging current;

[0069] in is the target current correction coefficient of the energy storage unit, ranging from 0.85 to 1.15. is the battery voltage value of the energy storage unit, is the target discharge current, is the target charging current;

[0070] In discharge mode, if the target discharge current Exceeding the maximum discharge current threshold, the target current is limited to the maximum discharge current threshold, and the safety threshold judgment result is set to the over-limit state. In the charging mode, the target charging current If the target current is lower than the inverse of the maximum charging current threshold, the target current is limited to the inverse of the maximum charging current threshold, and the safety threshold judgment result is set to an over-limit state; if the target current is within the charge and discharge current threshold range, the target current is maintained at its original value, and the safety threshold judgment result is set to a normal state;

[0071] When the target charge and discharge power value of the energy storage unit >=Power control mode switching threshold When the state of charge value SOC is within the state of charge threshold range, the output control mode is set to a constant power control mode, driving the energy storage converter to operate at a fixed power;

[0072] When the target charge and discharge power value <Power control mode switching threshold Or when the current state of charge value SOC exceeds the state of charge threshold range, the output control mode is set to a constant current control mode, driving the energy storage converter to charge and discharge with a fixed current, wherein, The power control mode switching threshold is in the range of 200W to 500W, and the state of charge threshold is set in the range of 25% to 85%;

[0073] The target current after the amplitude limiting process, the safety threshold judgment result and the output control mode are encapsulated as control parameters of the target charge and discharge power of the energy storage unit.

[0074] Furthermore, the target current correction coefficient of the photovoltaic module is dynamically adjusted according to the system operating status. Correction coefficient of target current of energy storage unit ,include:

[0075] The ambient temperature of the photovoltaic module is collected as an input parameter of the target current correction coefficient of the photovoltaic module, and the state of charge value SOC of the energy storage unit is collected as an input parameter of the target current correction coefficient of the energy storage unit;

[0076] When the ambient temperature of the photovoltaic module is higher than the set temperature threshold, in order to prevent the device from overheating, the target current correction coefficient value of the photovoltaic module is automatically reduced to reduce the target output current. The temperature threshold range is 35°C to 45°C;

[0077] When the current state of charge (SOC) of the energy storage unit is lower than the minimum charge limit threshold or higher than the maximum charge limit threshold, the target current correction factor of the energy storage unit is automatically adjusted. Reduce to a safe operating value range to avoid overcharging and discharging, with the lowest charge limit threshold being 15% and the highest charge limit threshold being set at 85%.

[0078] The grid access module 50 is used to generate a grid access instruction for controlling grid connection if the real-time photovoltaic power is lower than the load power demand and the state of charge value is lower than the set threshold, and send the access instruction to the grid for triggering the grid energy supply behavior.

[0079] Further, including:

[0080] Calculating a current photovoltaic power gap based on a difference between the load power demand and the real-time power of the photovoltaic module;

[0081] If the photovoltaic power gap is greater than zero and the current state of charge (SOC) of the energy storage unit is lower than the lower limit of the state of charge threshold range, it is determined that the photovoltaic module does not have the main supply capability and the energy storage unit does not have the discharge capability, and a grid access instruction is triggered. The grid access instruction includes a grid start flag and a grid access duration parameter. The duration is a time calculated based on the ratio of the load power demand to the photovoltaic power gap.

[0082] Sending the grid access instruction to the grid to start grid power supply, wherein the grid power supply is used to compensate for the load power gap that cannot be met by photovoltaic and energy storage, thereby ensuring power supply stability;

[0083] If it is determined that the real-time photovoltaic power is not less than the load power demand on the load side and the current state of charge value SOC of the energy storage unit is not lower than the upper limit of the state of charge threshold range, it is considered that the energy storage unit has recovered to a normal charging and discharging state, triggering a grid shutdown instruction to terminate the grid energy supply behavior.

[0084] Specifically, when the system detects that the real-time output power of the photovoltaic module is lower than the current load power demand, and the current state of charge value SOC of the energy storage unit is lower than the lower limit of the state of charge threshold range set by the system, it means that the photovoltaic and energy storage cannot provide enough energy to maintain the normal operation of the load at this stage. In order to ensure the continuity and stability of the power supply system, the system generates a grid access control instruction based on the above detection results, which includes a grid start-up identifier and access duration parameters. This instruction is sent to the grid with power supply control function through control communication to trigger the access operation on the grid side, so that the grid can supplement the current power gap. Specifically, the system first determines the load power demand based on the load power demand. Real-time output power of photovoltaic modules The difference between the current photovoltaic power gap is calculated as ΔP= - ; If ΔP>0, and the current state of charge value SOC< , that is, it is lower than the discharge safety threshold set by the system, and the system regeneration capacity is determined to be insufficient, triggering the above-mentioned grid access instruction. The access duration parameter can be based on the photovoltaic power gap ΔP and the load power demand The system calculates the ratio of power consumption to power demand, ensuring that the grid's energy replenishment behavior accurately matches the current supply and demand gap. Furthermore, the system continuously monitors the photovoltaic power and energy storage status. If the real-time output power of the photovoltaic module is not less than the load power demand, and the state of charge value SOC of the energy storage unit recovers to above the upper limit of the set threshold range, it is determined that the current renewable energy supply capacity has been restored. The system generates a grid shutdown instruction and sends it to the grid to terminate the grid access behavior, thereby returning to a green energy power supply path based on photovoltaics and energy storage. This solution can dynamically identify the supply and demand balance state, flexibly introduce the grid to ensure the reliability of the system operation, while avoiding unnecessary grid energy use and improving overall energy utilization efficiency.

[0085] In summary, the embodiments of the present application have at least the following technical effects:

[0086] The photovoltaic real-time power of the photovoltaic module is monitored in real time through the photovoltaic inverter, and the charge state value of the energy storage unit is obtained through the battery management system. The charge state value is used to indicate the percentage of the current energy storage unit power to its rated capacity, and the load power demand on the load side is monitored in real time through the current sensor and the voltage sensor; based on the preset photovoltaic priority energy supply strategy, the photovoltaic power weight coefficient and the energy storage power weight coefficient are dynamically calculated using the collected photovoltaic real-time power, charge state value and load power demand, and the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are obtained as the current power allocation scheme; according to the real-time changes in the load power demand, the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are dynamically adjusted. , and optimize the power distribution path based on the current supply and demand status to obtain a revised power distribution plan, wherein the power distribution path is used to indicate the power supply priority and power distribution ratio of the photovoltaic components and the energy storage unit to the load; based on the revised power distribution plan, a coordinated output control instruction including the control parameters of the target output power of the photovoltaic components and the control parameters of the target charge and discharge power of the energy storage unit is generated, and sent to the photovoltaic components and the energy storage unit to coordinate the execution of the joint power output in accordance with the revised power distribution plan; if the real-time photovoltaic power is lower than the load power demand and the state of charge value is lower than the set threshold, a grid access instruction for controlling the grid connection is generated, and the access instruction is sent to the grid for triggering the grid energy supply behavior.

[0087] It should be noted that the above-mentioned order of the embodiments of the present application is for descriptive purposes only and does not represent the superiority or inferiority of the embodiments. The above description is of specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0088] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

[0089] This specification and drawings are merely illustrative of the present application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Obviously, those skilled in the art may make various modifications and variations to this application without departing from the scope of this application. Thus, this application is intended to include such modifications and variations as fall within the scope of this application and its equivalents.

Claims

1. A coordinated control system for energy storage and power grid based on photovoltaic priority energy supply, characterized in that: include: A data acquisition module, which is used to monitor the real-time photovoltaic power of the photovoltaic modules through the photovoltaic inverter, obtain the state of charge value of the energy storage unit through the battery management system, and the state of charge value is used to indicate the percentage of the current energy storage unit power as a percentage of its rated capacity, and monitor the load power demand on the load side in real time through the current sensor and voltage sensor; A power allocation calculation module is used to dynamically calculate the photovoltaic power weight coefficient and the energy storage power weight coefficient based on the preset photovoltaic priority energy supply strategy and the collected photovoltaic real-time power, charge state value and load power demand, and obtain the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit as the current power allocation plan; The preset photovoltaic priority energy supply strategy includes: If the photovoltaic real-time power is not less than the load power demand, it is determined that the photovoltaic module has the main supply capability, and the photovoltaic power weight coefficient is set. =1, Energy storage power weight coefficient =0, the output power of the energy storage unit is not determined at all; If the photovoltaic real-time power is lower than the load power demand, and if the state of charge value is not lower than the energy storage discharge lower limit threshold set by the system, it is determined that the energy storage unit has discharge capacity and the photovoltaic power weight coefficient is set. =0, energy storage power weight coefficient =1; If the photovoltaic real-time power is not less than the set photovoltaic minimum effective output threshold, and the state of charge value is not less than the energy storage discharge lower limit threshold, and the dischargeable power calculated based on the current state of charge value, battery rated capacity, battery rated voltage and discharge efficiency is greater than zero, then it is determined that the photovoltaic module has the main power supply capability and the energy storage unit has the discharge capability; The calculation formula is as follows: ； ； in, is the photovoltaic real-time power, is the estimated discharge power of the energy storage unit, is the photovoltaic power weight coefficient, is the energy storage power weight coefficient, satisfying + =1; when When it increases, the Corresponding increase, The power is reduced accordingly, thereby allocating power to the photovoltaic module output first; The estimated dischargeable power of the energy storage unit is calculated as follows: ； in, is the rated capacity of the battery, is the rated voltage of the battery, is the current state of charge value of the energy storage unit, is the lower limit of the state of charge threshold range, is the discharge efficiency of the battery, is the estimated discharge power of the energy storage unit; The rated capacity of the battery is a device parameter preset in the system configuration, which is read and stored during the system deployment phase. The rated voltage of the battery is the nominal value provided by the battery at the factory. The discharge efficiency of the battery is preset by the system based on the model and characteristics of the selected energy storage unit. A dynamic power adjustment module, which is used to dynamically adjust the target output power of the photovoltaic modules and the target charge and discharge power of the energy storage unit according to the real-time changes in the load power demand, and optimize the power allocation path based on the current supply and demand status to obtain a revised power allocation plan. The power allocation path is used to indicate the power supply priority and power allocation ratio of the photovoltaic modules and energy storage units to the load; a coordinated output module, the coordinated output module being configured to generate, based on the revised power allocation scheme, coordinated output control instructions including control parameters for the target output power of the photovoltaic module and control parameters for the target charge and discharge power of the energy storage unit, and send the coordinated output control instructions to the photovoltaic module and the energy storage unit to coordinate the execution of a joint power output that complies with the revised power allocation scheme; A grid access module, wherein the grid access module is used to generate a grid access instruction for controlling grid connection if the real-time photovoltaic power is lower than the load power demand and the state of charge value is lower than the set threshold, and to send the access instruction to the grid for triggering the grid energy supply behavior.

2. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 1 is characterized in that: The preset photovoltaic priority energy supply strategy uses the collected photovoltaic real-time power, state of charge value and load power demand to dynamically calculate the photovoltaic power weight coefficient and the energy storage power weight coefficient, and obtains the photovoltaic module target output power and the energy storage unit target charge and discharge power as the current power allocation plan, including: Based on the preset photovoltaic priority energy supply strategy, the photovoltaic power weight coefficient and energy storage power weight coefficient for power distribution are obtained. Combined with the currently collected load power demand, the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are calculated respectively. The calculation formula is as follows: The target output power formula of photovoltaic modules is: = × ； in is the load power requirement, is the photovoltaic power weight coefficient, The target output power of the photovoltaic module; The target charging and discharging power formula of the energy storage unit is: = × ； in is the load power requirement, is the energy storage power weight coefficient, The target charge and discharge power of the energy storage unit. A positive value indicates discharge, and a negative value indicates charge.

3. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 1 is characterized in that: According to the real-time changes in the load power demand, the target output power of the photovoltaic module and the target charge and discharge power of the energy storage unit are dynamically adjusted, and the power allocation path is optimized based on the current supply and demand status to obtain a revised power allocation plan. The power allocation path is used to indicate the power supply priority and power allocation ratio of the photovoltaic module and the energy storage unit to the load, including: Calculate the average value of the load power demand in the current scheduling period and differentiate it from the average value of the load power demand in the previous scheduling period to obtain a load power change value; When the load power demand increases, that is, the load power change value is positive, and the photovoltaic real-time power is less than the photovoltaic maximum output power threshold set by the system, it is determined that the photovoltaic module has surplus power generation capacity. Based on the minimum value between the load power change value and the surplus power generation capacity, the target output power of the photovoltaic module is increased, and the energy storage unit maintains the current output state; When the load power change value is positive, and the photovoltaic real-time power output has reached the photovoltaic maximum output power threshold set by the system, and the state of charge value of the energy storage unit is higher than the discharge lower limit threshold set by the system, and the estimated dischargeable power of the energy storage unit is greater than zero, the discharge portion of the target charge and discharge power of the energy storage unit is increased to make up for the load power difference; When the load power demand decreases, that is, the load power change value is negative, the discharge portion of the target charge and discharge power of the energy storage unit is adjusted downward to avoid over-discharge while maintaining stable output of the photovoltaic module; Based on the available output power of the photovoltaic module and the discharge capacity of the energy storage unit, combined with the current load power demand, the priority of the photovoltaic energy supply path and the energy storage energy supply path is determined, and the main supply path is dynamically switched to achieve adjustment of the power distribution path and reconstruction of the energy flow direction. The available output power of the photovoltaic module is the maximum output power calculated based on the current light intensity and the maximum output power limit set by the system. The discharge capacity of the energy storage unit is the maximum discharge power that can be released to the load when its current state of charge value is higher than the lower discharge limit threshold set by the system; The dynamically adjusted target output power of the photovoltaic modules and the target charging and discharging power of the energy storage unit constitute a revised power allocation plan.

4. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 1 is characterized in that: The method includes generating, based on the revised power allocation plan, a coordinated output control instruction including control parameters for the target output power of the photovoltaic module and control parameters for the target charge and discharge power of the energy storage unit, and sending the coordinated output control instruction to the photovoltaic module and the energy storage unit to coordinate the execution of the combined power output in accordance with the revised power allocation plan, including: Extract the target output power value of the photovoltaic module from the modified power allocation scheme and the target charge and discharge power value of the energy storage unit ; Set the PV module target current correction coefficient that is dynamically adjusted according to the system operating status Correction coefficient of target current of energy storage unit ; The output voltage value of the current photovoltaic module side is obtained by collecting the real-time detection value of the DC side voltage of the photovoltaic inverter , based on the target output power value of the photovoltaic module The current output voltage value of the photovoltaic module side , calculate the target output current , The calculation formula is: ; in, is the target current correction coefficient of the photovoltaic module, and its value range is 0.8~1.2; The target output power value of the photovoltaic module is input into the maximum power point tracking controller MPPT, and the target voltage value is dynamically adjusted using the voltage disturbance method, combined with the target output current value , generating photovoltaic inverter control parameters including target voltage and target current as control parameters of target output power of photovoltaic modules; Determine the target charge and discharge power value of the energy storage unit to determine the positive and negative signs of the current energy storage unit control mode, and generate control parameters for the target charge and discharge power of the energy storage unit based on the control mode, wherein the control parameters for the target charge and discharge power of the energy storage unit include the target current after the limit processing, the safety threshold judgment result, and the output control mode; Encapsulating the control parameters of the target output power of the photovoltaic module and the control parameters of the target charge and discharge power of the energy storage unit into a coordinated output control instruction, wherein the coordinated output control instruction is used to adjust the output current of the photovoltaic inverter and control the charge and discharge state of the energy storage converter; The photovoltaic inverter and the energy storage converter are driven according to the coordinated output control instruction to coordinate and execute a joint power output that complies with the revised power allocation scheme.

5. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 4 is characterized in that: Determining the target charge and discharge power value of the energy storage unit to determine the current control mode of the energy storage unit, and generate control parameters of the target charge and discharge power of the energy storage unit based on the control mode, including: When the target charge and discharge power value of the energy storage unit > 0, the power control mode is determined to be discharge mode, and the target current calculation method is based on Calculate target discharge current; When the target charge and discharge power value of the energy storage unit < 0, the power control mode is determined to be charging mode, and the target current calculation method is based on = - Calculate the target charging current; in is the target current correction coefficient of the energy storage unit, ranging from 0.85 to 1.

15. is the battery voltage value of the energy storage unit, is the target discharge current, is the target charging current; In discharge mode, if the target discharge current Exceeding the maximum discharge current threshold, the target current is limited to the maximum discharge current threshold, and the safety threshold judgment result is set to the over-limit state. In the charging mode, the target charging current If the target current is lower than the opposite of the maximum charging current threshold, the target current is limited to the opposite of the maximum charging current threshold, and the safety threshold judgment result is set to an over-limit state; if the target current is within the charge and discharge current threshold range, the target current is maintained at its original value, and the safety threshold judgment result is set to a normal state; When the target charge and discharge power value of the energy storage unit >=Power control mode switching threshold When the state of charge value SOC is within the state of charge threshold range, the output control mode is set to a constant power control mode, driving the energy storage converter to operate at a fixed power; When the target charge and discharge power value <Power control mode switching threshold Or when the current state of charge value SOC exceeds the state of charge threshold range, the output control mode is set to a constant current control mode, driving the energy storage converter to charge and discharge with a fixed current, wherein, The power control mode switching threshold is in the range of 200W to 500W, and the state of charge threshold is set in the range of 25% to 85%; The target current after the amplitude limiting process, the safety threshold judgment result and the output control mode are encapsulated as control parameters of the target charge and discharge power of the energy storage unit.

6. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 4 is characterized in that: The setting is based on the dynamic adjustment of the photovoltaic module target current correction coefficient according to the system operating status Correction coefficient of target current of energy storage unit ,include: The ambient temperature of the photovoltaic module is collected as an input parameter of the target current correction coefficient of the photovoltaic module, and the state of charge value SOC of the energy storage unit is collected as an input parameter of the target current correction coefficient of the energy storage unit; When the ambient temperature of the photovoltaic module is higher than the set temperature threshold, in order to prevent the device from overheating, the target current correction coefficient value of the photovoltaic module is automatically reduced to reduce the target output current. The temperature threshold range is 35°C to 45°C; When the current state of charge (SOC) of the energy storage unit is lower than the minimum charge limit threshold or higher than the maximum charge limit threshold, the target current correction factor of the energy storage unit is automatically adjusted. Reduce to a safe operating value range to avoid overcharging and discharging, with the lowest charge limit threshold being 15% and the highest charge limit threshold being set at 85%.

7. The energy storage and grid coordination control system based on photovoltaic priority energy supply according to claim 1 is characterized in that: If the photovoltaic real-time power is lower than the load power demand and the state of charge value is lower than a set threshold, generating a grid access instruction for controlling grid connection, and sending the access instruction to the grid for triggering grid energy supply behavior, including: Calculating a current photovoltaic power gap based on a difference between the load power demand and the real-time power of the photovoltaic module; If the photovoltaic power gap is greater than zero and the current state of charge (SOC) of the energy storage unit is lower than the lower limit of the state of charge threshold range, it is determined that the photovoltaic module does not have the main supply capability and the energy storage unit does not have the discharge capability, and a grid access instruction is triggered. The grid access instruction includes a grid start flag and a grid access duration parameter. The duration is a time calculated based on the ratio of the load power demand to the photovoltaic power gap. Sending the grid access instruction to the grid to start grid power supply, wherein the grid power supply is used to compensate for the load power gap that cannot be met by photovoltaic and energy storage, thereby ensuring power supply stability; If it is determined that the real-time photovoltaic power is not less than the load power demand on the load side and the current state of charge value SOC of the energy storage unit is not lower than the upper limit of the state of charge threshold range, it is considered that the energy storage unit has recovered to a normal charging and discharging state, triggering a grid shutdown instruction to terminate the grid energy supply behavior.

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