Source grid load storage cooperative control method and device for electric hydrogen micro-grid

Abstract

The invention relates to the technical field of new energy power generation and micro-grid cooperative control, in particular to a source-grid load-storage cooperative control method and device for an electricity-hydrogen micro-grid, and the method aims at a photovoltaic system, provides a control strategy that a source moves along with the load, regulates and controls the photovoltaic power generation power in real time according to the dynamic change of the load, and guarantees the balance of supply and demand of the system. As for the energy storage unit, maintenance-emergency dual-mode control logic is designed, and dual guarantee of the service life of the energy storage unit and the operation stability of the system is achieved; a hierarchical control strategy is designed for the hydrogen fuel cell, the self operation characteristics are met, energy waste and equipment overload are avoided, and the multi-energy complementary supporting effect is enhanced. In an off-grid operation scene, a multi-source cooperative regulation and control mechanism is established, stable bus voltage of an energy storage unit is taken as a core, output of a photovoltaic system is regulated and controlled in a layered manner based on the charge state of the energy storage unit, and continuous and reliable power supply of a key load is guaranteed.

Description

A source-grid-load-storage coordinated control method and equipment for hydrogen-electricity microgrids Technical Field

[0001] This invention relates to the field of collaborative control technology for new energy power generation and microgrids, specifically to a source-grid-load-storage collaborative control method and equipment for hydrogen-electric microgrids. Background Technology

[0002] Microgrids, as the core carrier integrating diverse distributed energy sources such as photovoltaics, hydrogen fuel cells, and energy storage, have become a key technological direction for solving the bottleneck of traditional energy supply and improving the reliability and sustainability of energy systems due to their flexible power supply modes, high energy utilization efficiency, and precise response to load demand. The core function of microgrids lies in realizing the energy conversion and efficient flow of each link in the "source-grid-load-storage" chain through power electronic converters, and in achieving coordinated control and power balance of multiple energy sources through a centralized control system. This allows for precise matching of the dynamic relationship between power output, grid transmission, load demand, and energy storage regulation, ultimately ensuring the stable and efficient operation of the power supply system.

[0003] Currently, microgrids are rapidly developing towards multi-energy complementarity, high flexibility, and high reliability. Photovoltaics, as a clean and low-carbon distributed energy source, forms an electric-hydrogen core architecture with hydrogen fuel cells, as shown in Figure 1. This type of electric-hydrogen microgrid typically uses a DC bus as the core for energy aggregation and distribution. Photovoltaics, hydrogen fuel cells, and energy storage units are connected to the DC bus via DC / DC converters, and then converted from DC to AC power via bidirectional interconnection converters to provide power to AC loads. The centralized control system, as the control core of the electric-hydrogen microgrid, undertakes key tasks such as operational status monitoring and load matching. Its control logic and functional design determine the efficiency of multi-energy collaborative operation and the system's power supply stability.

[0004] However, with the expansion of microgrid scale, the increase in the types of energy connected, and the diversification of load demands, existing microgrids have gradually exposed many problems in areas such as source-grid-load-storage coordinated control, stable operation of multiple energy sources, and dynamic adaptability. These problems restrict the performance improvement and scenario expansion of microgrids, specifically manifested as follows: First, photovoltaic output regulation lacks a precise source-load matching mechanism, resulting in low energy utilization efficiency. In existing microgrids, photovoltaic output control mostly adopts constant power output or maximum power point tracking strategies, without establishing a source-load-following control logic that dynamically links with load demand. When load fluctuates, photovoltaics struggle to respond quickly and adjust their output power, leading to photovoltaic power being fed back to the grid or significant fluctuations in DC bus voltage. This results in power imbalance among the source, grid, load, and storage components, affecting the overall power supply stability and operational reliability of the system.

[0005] Secondly, the energy storage unit operates in a single, fixed mode, lacking a coordinated control logic that considers both maintenance and emergency response. As the core unit in a microgrid that smooths power fluctuations and ensures voltage stability, the operating status of the energy storage unit directly affects the stability of the microgrid and the lifespan of the energy storage system. During steady-state operation of the microgrid, the energy storage unit lacks a suitable self-maintenance strategy. Long-term idleness or disordered charging and discharging can lead to decreased battery activity, shortened cycle life, and increased operation and maintenance costs. When there are sudden load changes or the bus voltage exceeds the safe range, the energy storage unit cannot quickly switch to the voltage emergency regulation mode, making it difficult to quickly smooth voltage fluctuations, resulting in a decline in power quality and even threatening the safety of power equipment.

[0006] Third, hydrogen fuel cell output control lacks a hierarchical control mechanism and has insufficient coordination and adaptability. As a stable and reliable supplementary energy source in microgrids, hydrogen fuel cells have the characteristic of flexibly adjusting output. However, in existing technologies, hydrogen fuel cells mostly adopt a constant power output strategy. When the load is in different ranges, hydrogen fuel cells cannot match the appropriate output, resulting in low energy utilization efficiency in low-load scenarios and insufficient output in high-load scenarios, making it difficult to fully play its supporting role as a supplementary energy source.

[0007] Fourth, the operational modes are not fully covered, and there is a lack of reliable off-grid power supply solutions. Existing microgrid operational modes mostly focus on grid-connected operation scenarios, failing to fully consider off-grid power supply needs in special circumstances such as grid failures, maintenance, or remote areas without grid coverage. Furthermore, the off-grid mode lacks a linkage mechanism with energy storage unit voltage support and photovoltaic output regulation, making it impossible to guarantee voltage stability and power matching of off-grid loads. This results in poor off-grid power supply reliability and difficulty in meeting the continuous power supply needs of critical loads.

[0008] In summary, under the scenario of coordinated control of power generation, grid, load, and energy storage, the lack of priority and dynamic adjustment mechanisms for the coordination of photovoltaic power output with hydrogen fuel cells and energy storage units leads to poor multi-energy synergy, low energy utilization efficiency, and insufficient power supply stability. Therefore, there is an urgent need to develop a coordinated control method for power generation, grid, load, and energy storage in hydrogen-electricity microgrids to improve the operating efficiency and power supply reliability of the microgrid. Summary of the Invention

[0009] To address the problems in the existing technology, this invention provides a source-grid-load-storage coordinated control method and equipment for hydrogen-electric microgrids.

[0010] This invention is achieved through the following technical solution: a source-grid-load-storage coordinated control method for a hydrogen-electric microgrid. The microgrid includes a central control cabinet, which regulates the power supply unit formed by a photovoltaic system, a hydrogen fuel cell, and an energy storage unit. The power supply unit is connected to a DC / DC converter, which is connected to a bidirectional interconnected converter via a DC bus. The AC bus is connected to an AC load or to the distribution network via a main transformer. When the microgrid is operating normally, a hierarchical power regulation strategy of "hydrogen first, then photovoltaic" is adopted. Specifically: First, the hydrogen fuel cell sets its output power based on a preset load range division rule. When the actual output power of the hydrogen fuel cell is insufficient, the photovoltaic system sets its output power according to a "source follows load" strategy. The energy storage unit cooperates with the photovoltaic system to discharge and charge using a control logic of "bus voltage measurement - state hierarchical judgment - power reference value setting". When the microgrid fails, it adopts an off-grid operation mode. The hydrogen fuel cell shuts down, the energy storage unit is connected to the system in a constant voltage operation mode, and the photovoltaic system adjusts the output power of the DC / DC converter based on the total load power combined with the energy storage unit status and photovoltaic output characteristics.

[0011] Preferably, the preset load range division rules include: when the load is in the low power range During the interval, control the output of the hydrogen fuel cell. Constant low power; when the load is in the medium power range When fluctuations occur, the output power is adjusted to... Constant value; when the load is in the high power range At that time, hydrogen fuel cells used high power Power output.

[0012] Preferably, based on the different output power levels of hydrogen fuel cells, the energy storage unit is set with differentiated maximum charge and discharge power limits. The formula is as follows:

[0013] in, These represent low-power, medium-power, and high-power batteries, respectively.

[0014] Preferably, the photovoltaic system sets its output power according to a "source follows load" strategy. Specifically, this involves collecting real-time load data from each line, incorporating a power backfeed protection margin design, and obtaining the expected power of the bidirectional interconnect converter corresponding to the load of each line. Based on the expected power of the bidirectional interconnect converter Determine the maximum rated power ; at maximum rated power Determine the power reference value for the bidirectional interconnect converter corresponding to each line. Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line. Obtain a reference command for the power generation of a single photovoltaic unit. According to the power generation reference command of a single photovoltaic unit The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line. Obtain a reference command for the power generation of a single photovoltaic unit. This includes: firstly, obtaining a reference value for the output power of the photovoltaic system based on the number of bidirectional interconnected converters in operation, the real-time output power of the hydrogen fuel cell, and the real-time output power of the energy storage unit. The photovoltaic system is configured to consist of an array of multiple photovoltaic units with the same rated capacity. The reference value of the power generation of a single photovoltaic unit is based on... The formula is used to obtain the power output of a single photovoltaic unit, where m is the number of photovoltaic DC / DC converters in operation. The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. The rules are as follows: .

[0015] Preferably, the energy storage unit is based on the real-time DC bus voltage. Within the preset voltage safe operating threshold range The comparison switches between constant power self-maintenance mode and constant voltage mode. The comparison rule is: if the real-time DC bus voltage... If the voltage exceeds the specified range, an over-limit alarm signal will be immediately triggered, generating an energy storage unit operating condition switching command; among which... The commissioning and calibration were completed based on the characteristics of the on-site equipment parameters, actual operating conditions, and load fluctuation patterns.

[0016] Preferably, in constant power self-maintenance mode, when the energy storage unit operates with an autonomous charging and discharging maintenance mechanism, it includes: setting its normal operating range according to the energy storage unit's own parameters. First, determine whether the real-time SOC of the energy storage unit is less than [the value of the energy storage unit]. If this condition is met, the energy storage unit is determined to be in a low-charge state, and the charging process is initiated to replenish the energy storage unit's power; if the real-time SOC of the energy storage unit is greater than... If the energy storage unit is determined to be in a high-charge state, a discharge process is initiated to release the redundant charge of the energy storage unit until the SOC of the energy storage unit drops to 50%.

[0017] Preferably, in constant voltage mode, the power variation of the energy storage unit is limited to its maximum power. Within.

[0018] Preferably, the photovoltaic system adjusts the output power of the DC / DC converter based on the total load power, the energy storage unit status, and the photovoltaic output characteristics. Specifically, when the real-time SOC of the energy storage unit is at... During the specified range, the energy storage unit operates as a stable constant voltage source, compensating for bus power fluctuations in real time and ensuring that the DC bus voltage remains within the set stable range; when the real-time SOC of the energy storage unit is lower than... When the system is determined to be in a low-power state, the central control cabinet issues a photovoltaic power limiting adjustment command, reducing the photovoltaic power to [a certain level]. Improve on the basis This allows the photovoltaic system to release more redundant power for charging the energy storage unit until the energy storage unit's SOC rises above 50%, at which point additional charging scheduling stops, and the photovoltaic system resumes its normal power regulation logic; when the energy storage unit's SOC is higher than... When the system detects a high power level, the central control cabinet issues a command to reduce the photovoltaic power limit, lowering the photovoltaic power limit value. Discharge scheduling will stop and return to constant voltage support mode when the SOC drops below 50%.

[0019] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the steps of the method when executing the computer program.

[0020] Compared with existing technologies, this invention has the following advantages: The source-grid-load-storage coordinated control method for hydrogen-electric microgrids addresses technical problems such as multi-energy imbalance and low energy utilization efficiency in existing hydrogen-electric microgrids by constructing a multi-dimensional coordinated control system encompassing photovoltaics, energy storage units, hydrogen fuel cells, and bidirectional interconnected converters. Specifically, for the photovoltaic system, this invention proposes a source-follow-load control strategy, dynamically adjusting photovoltaic power generation in real time according to load changes to ensure system supply and demand balance. For the energy storage unit, a maintenance-emergency dual-mode control logic is designed to ensure both the lifespan of the energy storage unit and the stability of system operation. For the hydrogen fuel cell, a hierarchical control strategy is designed to suit its own operating characteristics, avoiding energy waste and equipment overload, and enhancing the complementary support effect of multiple energy sources. In off-grid operation scenarios, a multi-source coordinated control mechanism is established, with the energy storage unit stabilizing the bus voltage as the core, and the photovoltaic system output is hierarchically adjusted based on the energy storage unit's state of charge, ensuring continuous and reliable power supply to critical loads. Attached Figure Description

[0021] Figure 1 shows a typical electric-hydrogen microgrid structure; Figure 2 is a flow chart of the photovoltaic system source following the load in this invention; Figure 3 is a flow chart of the dual-mode operation of the energy storage unit for maintenance and emergency response in this invention; Figure 4 is a flow chart of the graded control output of the hydrogen fuel cell in this invention; Figure 5 is a flow chart of the off-grid mode collaborative operation in this invention. Detailed Implementation

[0022] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0023] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0024] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0025] In microgrids, distributed energy sources such as photovoltaics, hydrogen fuel cells, and energy storage units are all connected to the DC bus via DC / DC converters. The central control cabinet, as the core control unit of the system, undertakes the crucial function of multi-energy coordinated control. This invention aims to achieve coordinated control of all aspects of the energy source, grid, load, and storage systems, and designs a multi-energy complementary coordinated control algorithm to provide technical support for the efficient and stable operation of the electric-hydrogen microgrid. The following detailed description, in conjunction with specific embodiments, further illustrates the invention; however, this is intended to explain rather than limit the scope of the invention.

[0026] This invention discloses a source-grid-load-storage coordinated control method for hydrogen-electric microgrids. The method uses a typical hydrogen-electric microgrid as the hardware carrier, including a central control cabinet. The central control cabinet regulates the energy supply unit formed by a photovoltaic system, hydrogen fuel cell and energy storage unit to transmit energy. The energy supply unit is connected to a DC / DC converter. The DC / DC converter is connected to a bidirectional interconnected converter through a DC bus. The AC bus is connected to the AC load or to the distribution network through the main transformer.

[0027] This invention discloses a source-grid-load-storage coordinated control method for hydrogen-electric microgrids. Referring to Figures 2-5, when the microgrid is operating normally, a hierarchical power regulation strategy of "hydrogen first, then solar" is adopted. Specifically, firstly, the output power of the hydrogen fuel cell is set based on a preset load range division rule. The hydrogen fuel cell is used to adapt to different load ranges by tiered output, which is in line with its own operating characteristics, avoids energy waste and equipment overload, and enhances the complementary support effect of multiple energy sources.

[0028] The preset load range division rules include: when the load is in the low power range During the interval, control the output of the hydrogen fuel cell. Constant low power; when the load is in the medium power range When fluctuations occur, the output power is adjusted to... Constant value; when the load is in the high power range At that time, hydrogen fuel cells used high power Power output.

[0029] In one embodiment, the central control cabinet acquires total load power data in real time through a distributed acquisition module, and dynamically adjusts the output power of newly added hydrogen fuel cells based on preset load range division rules. When the load is in a low-power range... During the interval, control the output of the hydrogen fuel cell. Constant low power; when the load is in the medium power range When fluctuations occur, adjust its output power to Constant value; when the load is in the high power range At that time, hydrogen fuel cells used high power Power output. This segmented adjustment strategy allows the hydrogen fuel cell to always operate within a power range that matches the load demand, improving energy efficiency.

[0030] After completing the power allocation of the hydrogen fuel cell, the central control cabinet calculates the power gap that the photovoltaic system needs to make up based on the real-time load demand and the actual output power of the hydrogen fuel cell, and then automatically adjusts the power generation of each photovoltaic DC / DC converter to ensure that the total power generation is accurately matched with the load demand and maintain the power balance of the system.

[0031] In this mode, the energy storage unit prioritizes activating its autonomous charge / discharge maintenance mechanism. When the bus voltage experiences significant fluctuations, it switches to constant voltage mode, following the same procedure as step 2. To ensure the safe operation of newly added hydrogen fuel cell circuit breakers, cables, and other electrical equipment, differentiated maximum charge / discharge power limits are set for the energy storage unit based on the different output power levels of the hydrogen fuel cell. As shown in the following formula:

[0032] In the formula, These represent low-power, medium-power, and high-power batteries, respectively.

[0033] The aforementioned charging and discharging power limits are precisely controlled by the DC / DC converter integrated into the energy storage unit, ensuring that the equipment load remains within a safe threshold during multi-energy collaborative operation and improving system reliability.

[0034] When the actual output power of the hydrogen fuel cell is insufficient, the photovoltaic system sets its output power according to the "source follows load" strategy. Referring to Figure 2, this specifically involves: collecting real-time load data from each line, introducing a power backfeed protection margin design, and obtaining the expected power of the bidirectional interconnect converter corresponding to the load of each line. Based on the expected power of the bidirectional interconnect converter Determine the maximum rated power ; at maximum rated power Determine the power reference value for the bidirectional interconnect converter corresponding to each line. Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line. Obtain a reference command for the power generation of a single photovoltaic unit. According to the power generation reference command of a single photovoltaic unit The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. .

[0035] Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line Obtain a reference command for the power generation of a single photovoltaic unit. This includes: firstly, obtaining a reference value for the output power of the photovoltaic system based on the number of bidirectional interconnected converters in operation, the real-time output power of the hydrogen fuel cell, and the real-time output power of the energy storage unit. If the photovoltaic system is composed of an array of multiple photovoltaic units with the same rated capacity, then the reference value of the power generation of a single photovoltaic unit is as follows:

[0036] In the formula, m represents the number of photovoltaic DC / DC converters in operation. At this point, the power reference values ​​for each photovoltaic DC / DC converter and the bidirectional interconnected converter in the microgrid system have been calculated.

[0037] According to the power generation reference command of a single photovoltaic unit The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. The rules are as follows: .

[0038] At this point, the power reference values ​​of the bidirectional interconnection converters of AC and DC buses and the photovoltaic DC / DC converter in the system are calculated, and the switching logic of the energy storage unit's working mode is designed based on this power reference.

[0039] The energy storage unit coordinates with the photovoltaic system for discharging and charging using a control logic of "bus voltage measurement - state stratification determination - power reference value setting". In this mode, the energy storage unit prioritizes the activation of its autonomous charging and discharging maintenance mechanism, while the battery operates at low power, with the power limited to [specific value]. This periodic low-power charge-discharge cycle extends the cycle life and long-term operational reliability of the energy storage unit. The energy storage unit and the photovoltaic system form an integrated control logic of normal self-maintenance and emergency regulation, thereby realizing the coordinated operation of multiple devices and ensuring system stability. The specific control logic is shown in Figure 3.

[0040] The energy storage unit is based on the real-time DC bus voltage. Within the preset voltage safe operating threshold range The comparison switches between constant power self-maintenance mode and constant voltage mode. When sudden increases or decreases in load occur, such as the start-up or shutdown of high-power equipment or sudden load changes, the central control cabinet compares the measured bus voltage with the preset threshold in real time. The comparison rule is: if the real-time DC bus voltage... If the voltage exceeds the specified range, an over-limit alarm signal will be immediately triggered, generating an energy storage unit operating condition switching command; among which... Based on the characteristics of the on-site equipment parameters, actual operating conditions, and load fluctuation patterns, the commissioning and calibration were completed, and the initial setting was 0.9. ~1.1 .

[0041] After receiving the command, the energy storage unit quickly switches from constant power self-maintenance mode to constant voltage mode. It compensates for bus power shortages or absorbs redundant power by dynamically adjusting its output power, thus achieving rapid bus voltage stabilization. In constant power self-maintenance mode, the energy storage unit operates using an autonomous charging and discharging maintenance mechanism, including setting its normal operating range based on its own parameters. First, determine whether the real-time SOC of the energy storage unit is less than [the value of the energy storage unit]. If this condition is met, the energy storage unit is determined to be in a low-power state, and the charging process is started to replenish the energy storage unit's power. According to the storage performance test requirements of "6.6.1.2 Battery Module" in GB / T 36276-2023, charging can be stopped when the SOC of the energy storage unit rises to above 50%.

[0042] If the real-time SOC of the energy storage unit is greater than If the energy storage unit is determined to be in a high-charge state, a discharge process is initiated to release the redundant charge of the energy storage unit until the SOC of the energy storage unit drops to 50%.

[0043] In constant voltage mode, the power variation of the energy storage unit is limited to its maximum power. This is to avoid the impact of sudden power changes on the energy storage unit, circuit equipment, and system stability, to ensure a smooth transition during system power regulation, and to guarantee equipment operation safety and stable power supply quality.

[0044] After configuring the power reference value of the energy storage unit, the next iteration cycle is entered, and the complete logic of "bus voltage measurement - state layer determination - power reference value setting" is repeatedly executed to achieve dynamic adaptive control of the charging and discharging state of the energy storage unit, while ensuring the stability of the DC bus voltage and maintaining the reasonable range of the energy storage unit's SOC.

[0045] For the multi-device collaborative control logic in off-grid operation during grid faults, the microgrid adopts an off-grid operation mode, shutting down the hydrogen fuel cell to avoid redundant interference. The energy storage unit is connected to the system in a constant voltage operation mode, undertaking the function of DC bus voltage support and providing a voltage reference for stable system operation. The photovoltaic system adjusts the output power of the DC / DC converter based on the total load power combined with the energy storage unit status and photovoltaic output characteristics. In one embodiment, the central control cabinet obtains the power demand data of the total system load in real time through the data acquisition module, and dynamically adjusts the power generation of each photovoltaic DC / DC converter based on the energy storage unit status and photovoltaic output characteristics.

[0046] The photovoltaic system adjusts the output power of the DC / DC converter by combining the total load power with the status of the energy storage unit and the photovoltaic output characteristics. Specifically, referring to Figure 5, when the real-time SOC of the energy storage unit is at... During the specified range, the energy storage unit operates as a stable constant voltage source, compensating for bus power fluctuations in real time and ensuring that the DC bus voltage remains within the set stable range; when the real-time SOC of the energy storage unit is lower than... When the system is determined to be in a low-power state, the central control cabinet issues a photovoltaic power limiting adjustment command, reducing the photovoltaic power to [a certain level]. Improve on the basis This allows the photovoltaic system to release more redundant power for charging the energy storage unit until the energy storage unit's SOC rises above 50%, at which point additional charging scheduling stops, and the photovoltaic system resumes its normal power regulation logic; when the energy storage unit's SOC is higher than... When the system detects a high power level, the central control cabinet issues a command to reduce the photovoltaic power limit, lowering the photovoltaic power limit value. This creates power space for the energy storage unit to discharge, prompting the energy storage unit to release redundant power through discharge until the SOC drops below 50%, at which point the discharge scheduling stops and returns to the constant voltage support main mode.

[0047] The above-mentioned off-grid operation control logic ensures the safe operation of the energy storage unit under different power states through the SOC hierarchical regulation strategy. It can also achieve precise matching between photovoltaic power and the charging and discharging needs of the energy storage unit, maximizing the system's energy utilization efficiency and operational stability while ensuring independent and reliable power supply to off-grid loads.

[0048] This invention presents a source-grid-load-storage coordinated control method for hydrogen-electric microgrids. First, based on the dynamic response requirements of the load, a photovoltaic (PV) source-load-following control strategy is designed. By collecting real-time power consumption data from each load line and combining this with power backfeed prevention margin to calculate the PV system's power reference value, precise matching of PV output and load demand is achieved, reducing supply-demand imbalance and improving clean energy utilization and system power supply stability. Next, a dual-mode control logic for constant power self-maintenance and voltage emergency regulation of the energy storage unit is constructed, balancing the energy storage unit's lifespan and bus voltage stability. Based on the energy storage unit's State of Charge (SOC), a hierarchical determination is made to maintain power balance. When the DC bus voltage exceeds a safety threshold, a rapid switch to constant voltage mode is initiated. Then, a graded output control strategy for hydrogen fuel cells is used to output corresponding power according to the total load range, optimizing the multi-energy complementarity effect and avoiding equipment overload and frequent start-stop. Finally, an off-grid mode combined with coordinated rules and a multi-source linkage mechanism is designed to ensure independent power supply to critical loads, expanding application scenarios and improving the reliability and flexibility of microgrid power supply.

[0049] This invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions from a computer storage medium to implement the corresponding method flow or corresponding function.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the technical solution of the present invention in any way. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can be modified and replaced in several simple ways, and these modifications and replacements are all within the scope of protection covered by the claims.

Claims

1. A source-grid-load-storage coordinated control method for hydrogen-electricity microgrids, characterized in that, The microgrid includes a central control cabinet, which regulates the power supply unit consisting of a photovoltaic system, hydrogen fuel cells, and an energy storage unit. The energy supply unit is connected to a DC / DC converter, which is connected to a bidirectional interconnected converter (DC / AC inverter) via a DC bus. The AC bus is connected to the AC load or to the distribution network via a main transformer. During normal operation, the microgrid adopts a hierarchical power regulation strategy of "hydrogen first, then photovoltaic." Specifically: First, the hydrogen fuel cell sets its output power based on a preset load range division rule. When the actual output power of the hydrogen fuel cell is insufficient, the photovoltaic system sets its output power according to a "source follows load" strategy. The energy storage unit cooperates with the photovoltaic system to discharge and charge using the control logic of "bus voltage measurement - state hierarchical judgment - power reference value setting." In the event of a microgrid fault, an off-grid operation mode is adopted. The hydrogen fuel cell shuts down, the energy storage unit is connected to the system in a constant voltage operation mode, and the photovoltaic system adjusts the output power of the DC / DC converter based on the total load power combined with the energy storage unit status and photovoltaic output characteristics.

2. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 1, characterized in that, The preset load range division rules include: when the load is in the low power range During the interval, control the output of the hydrogen fuel cell. Constant low power; when the load is in the medium power range When fluctuations occur, the output power is adjusted to Constant value; when the load is in the high power range At that time, hydrogen fuel cells used high power Power output.

3. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 2, characterized in that, Based on the different output power levels of hydrogen fuel cells, energy storage units are set with differentiated maximum charge and discharge power limits. The formula is as follows: in, These represent low-power, medium-power, and high-power batteries, respectively.

4. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 3, characterized in that, The photovoltaic system sets its output power according to the "source follows load" strategy. Specifically, it collects real-time load data from each line, incorporates a power backfeed protection margin design, and obtains the expected power of the bidirectional interconnected converter corresponding to the load of each line. ； Based on the expected power of the bidirectional interconnect converter Determine the maximum rated power ； At maximum rated power Determine the power reference value for the bidirectional interconnect converter corresponding to each line. Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line. Obtain a reference command for the power generation of a single photovoltaic unit. According to the power generation reference command of a single photovoltaic unit The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. 。 5. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 4, characterized in that, Based on the power reference values ​​of the bidirectional interconnect converters corresponding to each line Obtain a reference command for the power generation of a single photovoltaic unit. This includes: firstly, obtaining a reference value for the output power of the photovoltaic system based on the number of bidirectional interconnected converters in operation, the real-time output power of the hydrogen fuel cell, and the real-time output power of the energy storage unit. The photovoltaic system is configured to consist of an array of multiple photovoltaic units with the same rated capacity. The reference value of the power generation of a single photovoltaic unit is based on... The formula is used to obtain the power output of a single photovoltaic unit, where m is the number of photovoltaic DC / DC converters in operation. The actual output power of a single photovoltaic unit is determined by the power value of that unit at its maximum power point. The rules are as follows: 。 6. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 1, characterized in that, The energy storage unit is based on the real-time DC bus voltage. Within the preset voltage safe operating threshold range The comparison switches between constant power self-maintenance mode and constant voltage mode. The comparison rule is: if the real-time DC bus voltage... If the voltage exceeds the specified range, an over-limit alarm signal will be immediately triggered, generating an energy storage unit operating condition switching command; among which... The commissioning and calibration were completed based on the characteristics of the on-site equipment parameters, actual operating conditions, and load fluctuation patterns.

7. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 6, characterized in that, In constant power self-maintenance mode, when the energy storage unit operates with an autonomous charging and discharging maintenance mechanism, it includes: setting its normal operating range according to the energy storage unit's own parameters. First, determine whether the real-time SOC of the energy storage unit is less than [the value of the energy storage unit]. If this condition is met, the energy storage unit is determined to be in a low-charge state, and the charging process is initiated to replenish the energy storage unit's power; if the real-time SOC of the energy storage unit is greater than... If the energy storage unit is determined to be in a high-charge state, a discharge process is initiated to release the redundant charge of the energy storage unit until the SOC of the energy storage unit drops to 50%.

8. The source-grid-load-storage coordinated control method for hydrogen-electricity microgrids according to claim 6, characterized in that, In constant voltage mode, the power variation of the energy storage unit is limited to its maximum power. Within.

9. The source-grid-load-storage coordinated control method for hydrogen-electric microgrids according to claim 7, characterized in that, The photovoltaic system adjusts the output power of the DC / DC converter by combining the total load power with the status of the energy storage unit and the photovoltaic output characteristics. Specifically: when the real-time SOC of the energy storage unit is at... During the specified range, the energy storage unit operates as a stable constant voltage source, compensating for bus power fluctuations in real time and ensuring that the DC bus voltage remains within the set stable range; when the real-time SOC of the energy storage unit is lower than... When the system is determined to be in a low-power state, the central control cabinet issues a photovoltaic power limiting adjustment command, reducing the photovoltaic power to [a certain level]. Improve on the basis This allows the photovoltaic system to release more redundant power for charging the energy storage unit until the energy storage unit's SOC rises above 50%, at which point additional charging scheduling stops, and the photovoltaic system resumes its normal power regulation logic; when the energy storage unit's SOC is higher than... When the system detects a high power level, the central control cabinet issues a command to reduce the photovoltaic power limit, lowering the photovoltaic power limit value. Discharge scheduling will stop and return to constant voltage support mode when the SOC drops below 50%.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-9.

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