Optical storage and charging integrated intelligent micro-grid system and control method thereof

Abstract

The invention provides an optical storage and charging integrated intelligent micro-grid system and a control method thereof. The optical storage and charging integrated intelligent micro-grid system comprises a photovoltaic power generation unit used for converting solar energy into electric energy; the energy storage unit is electrically connected with the photovoltaic power generation unit and is used for storing electric energy and releasing the electric energy under a preset condition; the charging unit is used for providing charging service for the electric vehicle; the load unit comprises a plurality of electric devices; the control unit is in communication connection with the photovoltaic power generation unit, the energy storage unit, the charging unit and the load unit, and is used for monitoring operation state data of each unit and coordinately controlling energy flow among the public power grid, the photovoltaic power generation unit, the energy storage unit, the charging unit and the load unit according to a preset microgrid operation control strategy; the method is used for realizing efficient local consumption of photovoltaic power generation, intelligent scheduling of the charging load of the electric vehicle and joint optimization of the overall operation economy and safety of the system in typical scenes such as industrial parks and the like.

Description

Technical Field

[0001] This invention belongs to the field of microgrid technology, specifically relating to an integrated photovoltaic, energy storage, and charging smart microgrid system and its control method. Background Technology

[0002] Distributed photovoltaic (PV) power generation is widely used due to its high flexibility and diverse grid connection methods. However, PV power generation is significantly affected by factors such as weather, resulting in intermittent and unstable output. Direct grid connection can easily cause shocks and disturbances to the power grid. At the same time, with the continuous growth in electricity demand in industrial parks, commercial parks, and other locations, there is an urgent need to build an efficient and reliable energy supply system to ensure their energy needs and reduce the burden on the public power grid.

[0003] Furthermore, with the deepening of energy structure transformation and the rapid popularization of electric vehicles, the problem of high-proportion integration and effective consumption of distributed renewable energy is becoming increasingly prominent. Traditional grid systems and simple photovoltaic-storage-charging systems often struggle to achieve real-time supply and demand balance when faced with the superposition of fluctuating photovoltaic power generation and stochastic electric vehicle charging loads, easily leading to grid fluctuations. Existing systems mostly adopt relatively simple grid-connected or off-grid operation modes, lacking coordinated optimization and intelligent control among power generation, energy storage, charging, and conventional loads, resulting in low overall energy utilization efficiency, insufficient operational economy, and a need to improve the level of system safety and stability.

[0004] Therefore, how to achieve efficient local consumption of photovoltaic power generation, intelligent scheduling of electric vehicle charging load, and joint optimization of the overall system's economic efficiency and safety in typical scenarios such as industrial parks has become a key technical problem that urgently needs to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an integrated photovoltaic, energy storage, and charging smart microgrid system and its control method, which is used in typical scenarios such as industrial parks to achieve efficient local consumption of photovoltaic power generation, intelligent scheduling of electric vehicle charging loads, and joint optimization of the overall system's operational economy and safety.

[0006] The technical solution of this invention is: an integrated photovoltaic, energy storage, and charging smart microgrid system, comprising: Photovoltaic power generation units are used to convert solar energy into electrical energy; An energy storage unit, electrically connected to the photovoltaic power generation unit, is used to store electrical energy and release it under preset conditions. Charging units are used to provide charging services for electric vehicles; Load units include various electrical devices; The control unit is communicatively connected to the photovoltaic power generation unit, energy storage unit, charging unit, and load unit, respectively, and is used to monitor the operating status data of each unit and coordinate and control the energy flow between the public power grid, the photovoltaic power generation unit, the energy storage unit, the charging unit, and the load unit according to the predetermined microgrid operation control strategy.

[0007] Furthermore, the photovoltaic power generation unit includes distributed solar panels that are installed on the roof of a building and / or the top of a charging facility carport.

[0008] Furthermore, the solar panel is a monocrystalline silicon photovoltaic module.

[0009] Furthermore, the energy storage unit includes an energy storage battery and a bidirectional energy storage converter, wherein the bidirectional energy storage converter is used to realize the charging and discharging control and AC-DC conversion of the energy storage battery.

[0010] Furthermore, the energy storage battery is a lead-acid battery.

[0011] Furthermore, the electrical equipment in the load unit includes office equipment, environmental control equipment, and security equipment.

[0012] The control method for the integrated photovoltaic, energy storage, and charging smart microgrid system described in any of the preceding claims includes the following steps: Data acquisition and monitoring: Real-time acquisition of operating power data from the photovoltaic power generation unit, energy storage unit, charging unit, and load unit; Power coordination and optimization control: Based on the operating power data, the microgrid operation control strategy is executed to dynamically adjust the charging and discharging state of the energy storage unit and the charging power of the charging unit in order to optimize the system power balance; Economic dispatch: Based on time-of-use electricity price information, the energy storage unit is controlled to charge during off-peak hours and discharge during peak hours; Security protection: When an abnormal system operation is detected, corresponding protection commands are executed.

[0013] Furthermore, in the power coordination and optimization control step, the microgrid operation control strategy includes the following decision logic: Power balance decision, used to generate the first charge and discharge command for the energy storage unit based on the real-time difference between photovoltaic power generation and total load demand; Economic dispatch decision-making is used to generate a second charge and discharge dispatch plan for the energy storage unit based on time-of-use electricity price information; The multi-objective coordination logic is used to arbitrate the first charge / discharge command and the second charge / discharge scheduling plan according to preset priority rules, and output the final control command to the energy storage unit and the charging unit.

[0014] Furthermore, in the economic scheduling step, when the economic scheduling conflicts with the power balance optimization in the power coordination and optimization control step of the energy storage unit, it has a higher control priority.

[0015] Furthermore, in the safety protection steps, the abnormal system operation includes overload, overheating, or three-phase imbalance, and the protection command includes stopping operation or limiting power.

[0016] The beneficial effects of this invention are: (1) The integrated photovoltaic, energy storage and charging smart microgrid system in this invention integrates the originally independent power generation, energy storage, power consumption and charging equipment into a controllable whole, laying a physical foundation for subsequent intelligent optimization operation and solving the problem of scattered and independent units in traditional systems that are difficult to coordinate. (2) The system has the advantages of high integration, high intelligence and high reliability. It can effectively reduce the power consumption of the power grid and meet the clean, intelligent and near-zero power consumption needs of industrial parks. It has broad application prospects and good economic benefits. (3) The photovoltaic power generation units are distributed and utilize idle or ancillary spaces such as building rooftops and charging sheds. Without occupying additional land resources, the construction of solar power generation facilities is realized, which improves the efficiency of space utilization. The distributed layout is also conducive to the local consumption of electricity and reduces transmission losses. (4) The control method of the integrated photovoltaic, energy storage and charging intelligent microgrid system decomposes the operation objectives into three levels: safety, balance and economy. These are achieved one by one through process steps, so that the system can be upgraded from a simple stack of equipment to an intelligent microgrid that can make autonomous optimization decisions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the integrated photovoltaic, energy storage, and charging smart microgrid system of the present invention.

[0018] Figure 2 This is a schematic diagram of the topology of the integrated photovoltaic, energy storage and charging smart microgrid system in this invention.

[0019] Figure 3 This is a communication architecture diagram of the integrated photovoltaic, energy storage, and charging smart microgrid system in this invention. Detailed Implementation

[0020] Various exemplary embodiments of the invention will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the invention or its application or use. The invention can be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the invention thorough and complete, and to fully express the scope of the invention to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0021] The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "comprising" mean that the element preceding the word encompasses the element listed after it, without excluding the possibility of encompassing other elements. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] like Figure 1 and 2 As shown, a photovoltaic, energy storage, and charging integrated smart microgrid system is disclosed, comprising: Photovoltaic power generation unit 1 is used to convert solar energy into electrical energy; Energy storage unit 2 is electrically connected to photovoltaic power generation unit 1 and is used to store electrical energy and release electrical energy under preset conditions; Charging unit 3 is used to provide charging services for electric vehicles; Load unit 4 includes various electrical devices; The control unit 5 is communicatively connected to the photovoltaic power generation unit 1, the energy storage unit 2, the charging unit 3, and the load unit 4, respectively. It is used to monitor the operating status data of each unit and coordinate the energy flow between the public power grid, the photovoltaic power generation unit 1, the energy storage unit 2, the charging unit 3, and the load unit 4 according to the predetermined microgrid operation control strategy.

[0023] In this embodiment, the control unit 5 serves as the core, acquiring data from the entire system through a communication link and uniformly directing the flow of electrical energy between the power grid, photovoltaics, energy storage, charging piles, and loads based on a pre-set microgrid operation control strategy. This integrates the originally independent power generation, energy storage, power consumption, and charging equipment into a controllable whole, laying the physical foundation for subsequent intelligent optimization operation and solving the problem of dispersed and independent units that are difficult to coordinate in traditional systems.

[0024] In some embodiments, the photovoltaic power generation unit 1 includes distributed solar panels installed on building roofs and / or the roofs of charging facility sheds. The distributed arrangement of the photovoltaic power generation unit utilizes idle or ancillary spaces such as building roofs and charging shed roofs, achieving the construction of solar power generation facilities without additional land use and improving space utilization efficiency. Distributed arrangement also facilitates the local consumption of electricity, reducing transmission losses.

[0025] In some embodiments, the solar panel is a monocrystalline silicon photovoltaic module; a monocrystalline silicon photovoltaic module is a photovoltaic material with a complete crystal structure and few impurities; a monocrystalline silicon photovoltaic module has the highest photoelectric conversion efficiency among currently commercial photovoltaic technologies; using this module can generate more power under the same illumination and installation area, thereby improving the energy output and economy of the entire system.

[0026] In some embodiments, the energy storage unit 2 includes an energy storage battery and a bidirectional energy storage converter. The bidirectional energy storage converter is used to realize the charging and discharging control of the energy storage battery and AC-DC conversion. The bidirectional energy storage converter has the key to having both charging and discharging capabilities and being able to be seamlessly connected to the AC microgrid, making the energy storage unit a flexible energy buffer within the system.

[0027] In some embodiments, the energy storage battery is a lead-acid battery; lead-acid batteries are technologically mature, relatively low in cost, highly reliable, and have a well-established recycling system; they are particularly suitable for application scenarios that are sensitive to initial investment or emphasize stability; in some embodiments, the energy storage battery can also be replaced with other existing energy storage batteries such as lithium batteries.

[0028] In some embodiments, the electrical equipment in load unit 4 includes office equipment, environmental control equipment, and security equipment; this clarifies the load range served by the system and reflects its typical characteristics of being applicable to scenarios such as industrial and commercial parks and office buildings. Including high-power adjustable loads such as air conditioners also makes demand-side management possible through control strategies.

[0029] In some embodiments, a control method for any of the above-mentioned integrated photovoltaic, energy storage, and charging smart microgrid systems is disclosed, comprising the following steps: Data acquisition and monitoring: Real-time acquisition of operating power data from photovoltaic power generation units, energy storage units, charging units, and load units; Power coordination and optimization control: Based on the operating power data, the microgrid operation control strategy is executed to dynamically adjust the charging and discharging state of the energy storage unit and the charging power of the charging unit in order to optimize the system power balance; Economic dispatch: Based on time-of-use electricity price information, control the energy storage units to charge during off-peak hours and discharge during peak hours; Security protection: When an abnormal system operation is detected, corresponding protection commands are executed.

[0030] In this embodiment, the control method of the integrated photovoltaic, energy storage and charging smart microgrid system decomposes the operation objectives into three levels: safety, balance and economy. These are achieved step by step through a process, which upgrades the system from a simple stack of equipment to a smart microgrid capable of autonomous optimization and decision-making.

[0031] In some embodiments, the microgrid operation control strategy in the power coordination and optimization control step includes the following decision logic: Power balance decision is used to generate the first charge and discharge command for the energy storage unit based on the real-time difference between photovoltaic power generation and total load demand; Economic dispatch decision-making is used to generate a second charge and discharge dispatch plan for energy storage units based on time-of-use electricity price information; The multi-objective coordination logic is used to arbitrate the first charge / discharge command and the second charge / discharge scheduling plan according to preset priority rules, and output the final control command to the energy storage unit and the charging unit.

[0032] Specifically, the microgrid operation control strategy includes the following steps: Step 1: The system collects real-time data on photovoltaic power generation (Ppv), electric vehicle charging power (Pev), and conventional load power (Pload); it also obtains current time-of-use electricity price information.

[0033] Step 2: Power balance decision: Real-time calculation of net power Pnet = Ppv - Pload - Pev; Judgment and generation: If Pnet > 0, it means that the photovoltaic power generation has a surplus, and the first charge and discharge command is generated as "charge", with the target power of the command being min(Pnet, maximum charging power of energy storage); if Pnet < 0, it means that the photovoltaic power generation is insufficient, and the first charge and discharge command is generated as "discharge", with the target power of the command being min(-Pnet, maximum discharging power of energy storage). Economic dispatch decision: Based on the current time and electricity price curve, determine the current time period (peak, off-peak, flat period); if it is a peak period, generate a second charging and discharging plan as "discharging" to obtain the maximum electricity sales revenue or reduce high-priced electricity purchases; if it is an off-peak period, generate a second charging and discharging plan as "charging" to store electricity at the lowest cost; if it is a flat period or other plans, set "maintain" or according to other strategies. Step 3: Conflict detection. Compare the "first instruction" (e.g., request to charge) with the "second plan" (e.g., request to discharge). If they match, there is no conflict; if they are opposite, a conflict has occurred. Arbitration enforcement, when a conflict arises, makes a ruling based on "pre-defined priority rules"; The command output sends the final control command, which includes a clear charging / discharging status and target power value after arbitration or without conflict, to the energy storage unit and the charging unit. Step 4: The energy storage converter and charging pile receive and execute the final command; the system state changes accordingly, new power data is collected, the process returns to the starting point, forming a closed-loop, continuously optimized control cycle.

[0034] This control method decouples the two objectives of real-time power balance and economic optimization into parallel decision-making, and then resolves potential conflicts through explicit coordination rules, thereby realizing a dynamic trade-off between ensuring real-time power balance and pursuing optimal economic operation.

[0035] As an example of the aforementioned predefined priority rules, these rules are implemented as a state machine or decision table based on the system state; for example, multi-objective coordination logic checks conditions and performs arbitration in the following order: Safety First: If the energy storage unit's charge status is below the minimum safety threshold (e.g., 20%) or above the maximum safety threshold (e.g., 95%), protective charging / discharging or standby commands will be executed first, overriding all other commands.

[0036] Economic efficiency priority: Provided that safety conditions are met, if the current period is during peak / valley electricity price periods, the plan generated by the economic dispatch decision will be adopted as the final instruction.

[0037] Power balance: If the current electricity price is flat or the economic dispatch plan is set to 'maintain', then the instructions generated by the power balance decision will be adopted.

[0038] The preset priority rules are stored in the control unit in the form of software code and are executed by the processor in cycles.

[0039] In some embodiments, during the economic dispatching step, when the charging and discharging operation of the energy storage unit conflicts with the power balance optimization in the power coordination and optimization control step, economic dispatching has a higher control priority. By setting economic dispatching to have a higher control priority, the maximum economic benefits on the user side can be ensured. In most commercial applications, cost reduction is the core demand. This priority setting makes the system, under the premise of safety, tend to make decisions in a mode that is more conducive to saving electricity costs, which directly improves the return on investment of the project.

[0040] In some embodiments, the system malfunctions during the safety protection steps include overload, overheating, or three-phase imbalance. The protection commands include stopping operation or limiting power, and displaying fault information through a human-machine interface to ensure the safe and stable operation of the system. This establishes a baseline rule for the safe operation of the system. By monitoring and responding quickly to key electrical anomalies, it effectively prevents equipment damage and the escalation of accidents, ensuring the long-term stable and reliable operation of the microgrid system. This is a prerequisite for the realization of all advanced functions.

[0041] Specifically, the control unit continuously collects key data through sensors distributed throughout the system: monitoring the current of each line to prevent overload, analyzing the current balance of the three phases, and continuously monitoring the temperature of core equipment such as energy storage converters and photovoltaic inverters. Once the monitored data exceeds the preset safety threshold, the system immediately enters the intelligent judgment and graded response stage. For example, when the current of a line exceeds the limit for the first time, the system will first issue a warning signal and record it, reminding of the potential overload risk. If the abnormality continues or worsens, such as a continuous rise in temperature, the system will execute a "power limit" command, actively reducing the output of the energy storage system or charging pile to attempt to cool the equipment and eliminate the overload. Only when the abnormal situation deteriorates rapidly, such as a severely excessive current or a temperature reaching a dangerous critical point, will the system decisively issue the highest-level stop operation command, quickly disconnecting the faulty part to ensure safety. After the protection action is executed, the process is not over; the system will enter the state tracking and self-recovery stage. The control unit continuously monitors whether the abnormality has been eliminated. Once the conditions are confirmed to have returned to normal and a preset stabilization period has elapsed, the system will automatically or gradually restore the normal operation of the equipment and reconnect it to the microgrid, thereby achieving a complete intelligent closed loop. This ensures that any anomalies can be handled in a timely manner, guaranteeing the long-term security and reliability of the entire microgrid infrastructure.

[0042] As a more specific implementation method of the integrated photovoltaic, energy storage, and charging smart microgrid system, such as Figure 3 As shown, the control unit 5 includes a PC host and a communication management unit. The PC host is connected to the communication management unit via a network cable. The PC host displays information on the screen. The communication management unit communicates with the hybrid energy storage controller, charging pile monitoring equipment, carport photovoltaic inverter, roof photovoltaic inverter and monitoring instruments via RS-485.

[0043] The various embodiments of the present invention have now been described in detail. To avoid obscuring the concept of the invention, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions disclosed herein based on the above description.

[0044] The embodiments described above only illustrate some implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A photovoltaic, energy storage, and charging integrated smart microgrid system, characterized in that, include: Photovoltaic power generation units are used to convert solar energy into electrical energy; An energy storage unit, electrically connected to the photovoltaic power generation unit, is used to store electrical energy and release it under preset conditions. Charging units are used to provide charging services for electric vehicles; Load units include various electrical devices; The control unit is communicatively connected to the photovoltaic power generation unit, energy storage unit, charging unit, and load unit, respectively, and is used to monitor the operating status data of each unit and coordinate and control the energy flow between the public power grid, the photovoltaic power generation unit, the energy storage unit, the charging unit, and the load unit according to the predetermined microgrid operation control strategy.

2. The integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 1, characterized in that: The photovoltaic power generation unit includes distributed solar panels that are installed on the roof of a building and / or the top of a charging facility carport.

3. The integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 2, characterized in that: The solar panel is a monocrystalline silicon photovoltaic module.

4. The integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 1, characterized in that: The energy storage unit includes an energy storage battery and a bidirectional energy storage converter. The bidirectional energy storage converter is used to realize the charging and discharging control of the energy storage battery and AC-DC conversion.

5. The integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 4, characterized in that: The energy storage battery is a lead-acid battery.

6. The integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 1, characterized in that: The electrical equipment in the load unit includes office equipment, environmental control equipment, and security equipment.

7. A control method for an integrated photovoltaic, energy storage, and charging smart microgrid system as described in any one of claims 1 to 6, characterized in that, Includes the following steps: Data acquisition and monitoring: Real-time acquisition of operating power data from the photovoltaic power generation unit, energy storage unit, charging unit, and load unit; Power coordination and optimization control: Based on the operating power data, the microgrid operation control strategy is executed to dynamically adjust the charging and discharging state of the energy storage unit and the charging power of the charging unit in order to optimize the system power balance; Economic dispatch: Based on time-of-use electricity price information, the energy storage unit is controlled to charge during off-peak hours and discharge during peak hours; Security protection: When an abnormal system operation is detected, corresponding protection commands are executed.

8. The control method for the integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 7, characterized in that: In the power coordination and optimization control steps, the microgrid operation control strategy includes the following decision logic: Power balance decision, used to generate the first charge and discharge command for the energy storage unit based on the real-time difference between photovoltaic power generation and total load demand; Economic dispatch decision-making is used to generate a second charge and discharge dispatch plan for the energy storage unit based on time-of-use electricity price information; The multi-objective coordination logic is used to arbitrate the first charge / discharge command and the second charge / discharge scheduling plan according to preset priority rules, and output the final control command to the energy storage unit and the charging unit.

9. The control method for the integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 7, characterized in that: In the economic dispatching step, when the economic dispatching conflicts with the power balance optimization in the power coordination and optimization control step of the energy storage unit, it has a higher control priority.

10. The control method for the integrated photovoltaic, energy storage, and charging smart microgrid system according to claim 7, characterized in that: In the safety protection steps, the abnormal system operation includes overload, overheating, or three-phase imbalance, and the protection command includes stopping operation or limiting power.

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