A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system

Abstract

This utility model relates to the field of integrated energy system technology and discloses a multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system. It includes a 750V DC bus platform, a photovoltaic power generation unit, a grid input terminal, a V2G charging pile, an energy storage unit, and a control cabinet cluster. The photovoltaic power generation unit includes a photovoltaic array, an MPPT controller, and a photovoltaic DC combiner box with a DC 750V output. The photovoltaic power generation unit is electrically connected to the 750V DC bus platform. The control cabinet cluster includes control cabinet one, control cabinet two, and control cabinet three. This utility model, through a multi-port DC power router architecture combined with intelligent control strategies, reduces AC / DC conversion links, significantly reducing energy loss, improving the overall energy utilization rate of the system, achieving energy complementarity and optimized configuration, enhancing the system's power supply capacity in emergency situations, and improving the reliability and stability of the power supply.

Description

Technical Field

[0001] This utility model relates to the field of integrated energy system technology, and in particular to a multi-port adjustable photovoltaic-storage-direct-flexible integrated energy power supply system. Background Technology

[0002] With increasing global emphasis on environmental protection and sustainable development, the energy structure is gradually shifting from traditional fossil fuels to renewable energy. Solar energy, as a clean and renewable energy source, has enormous development potential. However, solar photovoltaic power generation is intermittent and unstable, significantly affected by weather, seasons, and other factors. This necessitates the use of energy storage systems to smooth power fluctuations and ensure a stable energy supply. A multi-port adjustable photovoltaic-storage-direct-current-flexible integrated energy supply system is a power supply system that integrates multiple energy conversion and storage devices, has multiple output ports, and can flexibly control energy distribution to adapt to different load demands.

[0003] The photovoltaic-storage-direct-drive-flexible integrated energy power supply system integrates photovoltaic power generation and energy storage technologies, which can effectively utilize solar energy and reduce dependence on traditional fossil fuels. Therefore, it is necessary to develop a multi-port adjustable photovoltaic-storage-direct-drive-flexible integrated energy power supply system. Utility Model Content

[0004] To overcome the above shortcomings, this utility model provides a multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system, which aims to improve the problems of low photovoltaic absorption rate, large AC-DC conversion loss, insufficient multi-energy synergy, poor DC load compatibility, and rigid load regulation in the existing traditional photovoltaic building power supply system.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: a multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system, comprising a 750V DC bus platform, a photovoltaic power generation unit, a grid input terminal, a V2G charging pile, an energy storage unit, and a control cabinet cluster. The photovoltaic power generation unit includes a photovoltaic array, an MPPT controller, and a photovoltaic DC combiner box with a DC 750V output. The photovoltaic power generation unit is electrically connected to the 750V DC bus platform. The control cabinet cluster includes control cabinet one, control cabinet two, and control cabinet three. The grid input terminal is connected to the municipal power grid through controller one containing a 100kVA bidirectional PCS. The V2G charging pile is connected to the DC 750V bus via a DC / AC converter. The lithium battery pack of the energy storage unit is connected to the bus via a 50kW bidirectional DC-DC converter in control cabinet two. The DC end of the load side of the 750V DC bus platform supplies power for DC lighting and DC air conditioning. The AC end of the load side of the 750V DC bus platform is supplied by the PCS in control cabinet one, with a lower priority than the DC load.

[0006] The above technical solution involves constructing a 750V DC bus platform to regulate photovoltaic power generation control, V2G+ battery energy storage power regulation, DC power distribution protection, flexible load control, and microgrid operation control functions through an integrated photovoltaic-storage-DC-flexible control cabinet and a microgrid energy comprehensive regulation platform. This aims to maximize the local consumption of photovoltaic power generation and improve the flexible regulation capability of building energy systems.

[0007] As a further description of the above technical solution:

[0008] The multi-port energy router of the control cabinet 2 includes port 1, port 2, port 3, port 4, and port 5. Port 1 is electrically connected to a 100kVA AC grid port, port 2 is electrically connected to a V2G vehicle charging pile interface, port 3 is electrically connected to a 50kW bidirectional lithium battery charging and discharging interface, port 4 is electrically connected to a 100kWp photovoltaic input port, and port 5 is electrically connected to a DC output port with a total power of 20kW (DC375V±5%).

[0009] The above technical solution allows for real-time monitoring of parameters such as power, voltage, and battery status at each port through the connection of the control cabinet. It also enables dynamic adjustment of the operating mode, such as prioritizing photovoltaic, energy storage, and grid, thereby achieving optimized energy allocation and ensuring power supply reliability while adapting to grid fluctuations and emergency needs.

[0010] As a further description of the above technical solution:

[0011] The photovoltaic power generation unit has two parallel redundant 50kWp photovoltaic DC-DC converters on the photovoltaic side; the energy storage unit has a 50kW bidirectional DC-DC converter on the energy storage side.

[0012] The above technical solution improves the reliability of the photovoltaic unit through the parallel redundancy design of two 50kWp photovoltaic DC-DC converters, and can maintain continuous power supply to the system even if a single device fails.

[0013] As a further description of the above technical solution:

[0014] The photovoltaic DC-DC converter supports both maximum power point tracking (MPPT) and limited power point tracking (CPT) modes, and the energy storage DC-DC converter has constant voltage / constant current charge / discharge switching function.

[0015] Through the above technical solutions: the maximum power point tracking (MPPT) mode can maximize solar energy utilization and reduce the system's dependence on the grid; the power limited operation (CPT) mode can enhance the system's compatibility with the grid; and the energy storage DC-DC converter has constant voltage / constant current charging and discharging switching function, which can avoid damage to the battery caused by high current, ensure that the battery voltage is stable at the rated value, balance charging speed and battery safety, and extend the battery cycle life.

[0016] As a further description of the above technical solution:

[0017] The 750V DC bus platform adopts a three-level flexible DC voltage adaptation, which converts the voltage from DC750V to DC375V and from DC375V to DC48V.

[0018] The above technical solution—three-level DC voltage flexible adaptation, high-voltage DC bus reducing transmission loss, and low-voltage terminal reducing conversion loss—can improve the overall system energy efficiency and is compatible with DC equipment of different eras and power levels.

[0019] As a further description of the above technical solution:

[0020] The control cabinet includes an intelligent policy controller, a local monitoring station, and an industrial switch.

[0021] Through the above technical solution, the control cabinet three forms a complete control logic closed loop through the flexible scheduling of the intelligent policy controller, the real-time management of the local monitoring station, and the communication interconnection of the industrial switch.

[0022] As a further description of the above technical solution:

[0023] The intelligent strategy controller includes three operating modes: optical storage priority, V2G compensation, and off-grid islanding.

[0024] Through the above technical solution, the intelligent strategy controller can flexibly switch between three different operating modes according to different application scenarios and energy demands, thereby intelligently scheduling energy and realizing the coordinated operation between photovoltaics, energy storage, electric vehicles and the power grid. By monitoring and analyzing energy data in real time, the controller can dynamically adjust the energy distribution strategy, balance energy supply and demand, improve energy utilization efficiency and reduce overall operating costs.

[0025] As a further description of the above technical solution:

[0026] The industrial switch communicates with the upper-layer platform via the Modbus TCP / IP protocol.

[0027] Through the above technical solution, the combination of industrial switches and Modbus TCP / IP protocol can quickly and accurately transmit data to the upper-layer platform, and at the same time, it can promptly convey the control commands of the upper-layer platform to the lower-layer devices, ensuring real-time monitoring and control of the system, improving system management efficiency, and reducing operation and maintenance costs.

[0028] This utility model has the following beneficial effects:

[0029] 1. In this utility model, by using a multi-port DC power router architecture and combining it with intelligent control strategies, the AC / DC conversion links are reduced, which can significantly reduce energy loss, improve the overall energy utilization rate of the system, realize energy complementarity and optimized configuration, enhance the power supply capacity of the system in emergency situations, and improve the reliability and stability of power supply, thereby achieving the effect of promoting the transformation of the energy system towards low-carbon, intelligent and interactive.

[0030] 2. This utility model promotes the development of interaction between electric vehicles and the power grid, enhances the flexibility and interactivity of the system, supports off-grid operation, and improves the system's compatibility and adaptability to various equipment by adopting a three-level DC voltage flexible adaptation. The industrial switch facilitates remote monitoring and management by operators, reducing manual intervention. Attached Figure Description

[0031] Figure 1 This is a network architecture diagram of a multi-port adjustable photovoltaic-storage-direct-flexible integrated energy power supply system proposed in this utility model;

[0032] Figure 2 This is a network architecture diagram of a multi-port adjustable photovoltaic-storage-direct-flexible integrated energy power supply system proposed in this utility model. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] Reference Figure 1 and Figure 2This utility model provides an embodiment of a multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system, comprising a 750V DC bus platform, a photovoltaic power generation unit, a grid input terminal, a V2G charging pile, an energy storage unit, and a control cabinet cluster. The photovoltaic power generation unit includes a photovoltaic array, an MPPT controller, and a photovoltaic DC combiner box with a DC 750V output. The photovoltaic power generation unit is electrically connected to the 750V DC bus platform. The control cabinet cluster includes control cabinet one, control cabinet two, and control cabinet three. The grid input terminal is connected to the municipal power grid through controller one containing a 100kVA bidirectional PCS. The V2G charging pile is connected to the DC 750V bus via a DC / AC converter. The lithium battery pack of the energy storage unit is connected to the bus via a 50kW bidirectional DC-DC converter in control cabinet two. The DC end of the 750V DC bus platform load side supplies power for DC lighting and DC air conditioning. The AC end of the 750V DC bus platform load side is supplied by the PCS in control cabinet one, with a priority lower than that of the DC load.

[0035] Specifically, by directly connecting photovoltaics, energy storage, V2G, and loads to the DC bus, the AC / DC conversion process is reduced. V2G enables vehicle-to-grid interaction, achieving bidirectional energy flow between electric vehicles and the system. The control cabinet allows for seamless switching between grid-connected and off-grid operation, supporting ±10% voltage fluctuation adaptively. The DC load priority power supply mode reduces the number of AC / DC conversions and lowers losses. AC loads are used as a supplement, and priority control avoids impacting the core DC load, balancing energy efficiency and power supply reliability. Through the efficient interconnection of the 750V DC bus, the flexible collaboration of photovoltaics, energy storage, grid, and vehicles, and the hierarchical management of AC and DC loads, a comprehensive energy solution that is efficient, low-carbon, flexible, reliable, and enables vehicle-to-grid interaction is constructed.

[0036] Reference Figure 1 and Figure 2 The multi-port energy router in control cabinet 2 includes ports 1, 2, 3, 4, and 5. Port 1 is electrically connected to a 100kVA AC grid port, port 2 is electrically connected to a V2G vehicle charging pile interface, port 3 is electrically connected to a 50kW bidirectional lithium battery charging and discharging interface, port 4 is electrically connected to a 100kWp photovoltaic input port, and port 5 is electrically connected to a DC output port with a total power of 20kW (DC375V±5%).

[0037] Specifically, the connection through port 1 enables bidirectional regulation of the grid port, enhancing the reliability of the system's power supply, while also participating in grid peak shaving and improving the overall energy utilization rate. The connection through port 2 enhances system flexibility and helps build a V2G vehicle-to-grid interactive ecosystem. The connection through port 3 enables the storage and release of electrical energy. Multiple ports, including photovoltaic, energy storage, and load, operate collaboratively through flexible control strategies, enabling rapid response to grid dispatch commands or changes in load demand. The connection through port 4 allows for the efficient use of solar energy, reducing the system's dependence on traditional energy sources and achieving low-carbon power supply. The connection through port 5 provides a stable DC power supply for DC loads, eliminating the need for the AC / DC conversion stage in traditional AC systems.

[0038] Reference Figure 1 and Figure 2 The photovoltaic power generation unit has two parallel redundant 50kWp photovoltaic DC-DC converters on the photovoltaic side; the energy storage unit has a 50kW bidirectional DC-DC converter on the energy storage side; the photovoltaic DC-DC converter supports both maximum power point tracking (MPPT) and power-limited operation (CPT) modes, and the energy storage DC-DC converter has constant voltage / constant current charging and discharging switching function.

[0039] Specifically, by using two 50kWp photovoltaic DC-DC converters in parallel for redundancy, the system can dynamically adjust its power generation according to sunlight conditions. The 50kW bidirectional DC-DC converter at the energy storage end of the energy storage unit can achieve a charge-discharge efficiency of ≥98%, optimizing the energy storage system's charging efficiency. The photovoltaic DC-DC converter supports maximum power point tracking (MPPT), which can track the maximum power point of the photovoltaic array in real time when sunlight is sufficient, maximizing solar energy conversion efficiency and increasing system power generation. Through the power-limited operation (CPT) mode, the photovoltaic output power is actively limited under conditions of excessive sunlight or grid demand constraints, avoiding overload or curtailment and enhancing the system's compatibility with the grid.

[0040] Reference Figure 1 and Figure 2 The 750V DC bus platform adopts a three-level DC voltage flexible adaptation, converting DC750V to DC375V and DC375V to DC48V; Control cabinet three includes an intelligent strategy controller, a local monitoring station, and an industrial switch; The intelligent strategy controller includes three operating modes: optical storage priority, V2G compensation, and off-grid islanding; The industrial switch communicates with the upper-layer platform via the Modbus TCP / IP protocol;

[0041] Specifically, through multi-stage conversion from DC 750V to 375V to 48V, a three-level DC voltage flexible adaptation effect is achieved, thus matching the load requirements of different voltage levels within a building. This is more energy-efficient than the traditional two-stage AC-DC conversion scheme. The intelligent strategy controller enables multi-port energy coordination control and data acquisition. Equipped with an energy storage EMS algorithm, it supports photovoltaic forecasting, load forecasting, and V2G scheduling. The local monitoring station enables monitoring of the photovoltaic-storage-DC-flexible system status, operation control, human-machine interface, and data storage. The intelligent strategy controller provides flexible adjustment in multiple modes. An industrial-grade switch establishes a communication link between the underlying devices and the upper-level platform, enabling bidirectional transmission of data upload and command issuance in real time based on the Modbus TCP / IP protocol.

[0042] Working principle: Under sufficient sunlight, the photovoltaic array in the photovoltaic power generation unit can track the maximum power point in real time through the MPPT controller, and then convert it to 750V DC bus through the DC-DC converter to achieve grid-connected / off-grid switching, and prioritize power supply to DC loads. The grid is connected to the 750V bus through control cabinet one. Then, the V2G charging pile supports bidirectional energy flow, and can connect vehicle energy to the DC 750V bus through the DC / AC converter. The lithium battery pack of the energy storage unit can be connected to the DC 750V bus through the 50kW bidirectional DC-DC converter in control cabinet two. The system connects to the busbar for dynamic charging and discharging adjustment. During the two-stage voltage conversion of the control cabinet cluster (DC750V→DC375V, DC375V→DC48V with 96% efficiency), the DC terminals on the load side are supplied with power in stages: the 375V DC bus powers the DC air conditioning, and the 48V DC bus powers the DC lighting. The multi-port energy router in control cabinet two pioneers a four-port DC bus architecture integrating photovoltaics, energy storage, V2G, and the power grid. Furthermore, bidirectional energy routing can be achieved through control cabinet two, while intelligent strategy control in control cabinet three... The device features three intelligent control strategies. In areas with ample sunlight, Mode 1 (PV-storage priority) can be selected, prioritizing the PV-storage connection. The DC 750V bus directly supplied by the PV power generation prioritizes the 48V / 375V DC terminals. The remaining energy is then fed back to the V2G vehicle battery via the bidirectional PCS when the SOC is less than 95%. In areas with insufficient PV output, Mode 2 (V2G compensation mode) can be selected. The energy storage EMS dynamically calculates the power deficit and prioritizes V2G battery discharge based on their SOC. Battery discharge is prioritized when the SOC is greater than 80%. Simultaneously, the V2G discharge is processed via… The DC / AC converter is converted to a DC 750V supplementary bus, while limiting the amount of electricity purchased from the grid. In the event of a grid fault, the off-grid islanding operation mode (Mode 3) can be selected. Once the control cabinet disconnects from the grid, an islanded microgrid consisting of photovoltaics, V2G energy storage, and lithium batteries is formed. The intelligent strategy controller unloads loads according to load level, ensuring the stability of the DC 375V bus voltage. By integrating photovoltaics, energy storage, V2G, the grid, and multiple DC loads through the 750V DC bus platform, combined with intelligent control strategies, efficient, flexible, and low-carbon integrated energy management is achieved.

[0043] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy supply system, comprising a 750V DC bus platform, a photovoltaic power generation unit, a grid input terminal, a V2G charging pile, an energy storage unit, and a control cabinet cluster, characterized in that: The photovoltaic power generation unit includes a photovoltaic array, an MPPT controller, and a photovoltaic DC combiner box with a DC 750V output. The photovoltaic power generation unit is electrically connected to a 750V DC bus platform. The control cabinet cluster includes control cabinet one, control cabinet two, and control cabinet three. The grid input terminal is connected to the municipal power grid through controller one containing a 100kVA bidirectional PCS. The V2G charging pile is connected to the DC 750V bus via a DC / AC converter. The lithium battery pack of the energy storage unit is connected to the bus via a 50kW bidirectional DC-DC converter in control cabinet two. The DC end of the load side of the 750V DC bus platform supplies power for DC lighting and DC air conditioning. The AC end of the load side of the 750V DC bus platform is supplied by the PCS in control cabinet one, and its priority is lower than that of the DC load.

2. The multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 1, characterized in that: The multi-port energy router of the control cabinet 2 includes port 1, port 2, port 3, port 4, and port 5. Port 1 is electrically connected to a 100kVA AC grid port, port 2 is electrically connected to a V2G vehicle charging pile interface, port 3 is electrically connected to a 50kW bidirectional lithium battery charging and discharging interface, port 4 is electrically connected to a 100kWp photovoltaic input port, and port 5 is electrically connected to a DC output port with a total power of 20kW (DC375V±5%).

3. The multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 1, characterized in that: The photovoltaic power generation unit has two parallel redundant 50kWp photovoltaic DC-DC converters on the photovoltaic side; the energy storage unit has a 50kW bidirectional DC-DC converter on the energy storage side.

4. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 3, characterized in that: The photovoltaic DC-DC converter supports both maximum power point tracking (MPPT) and limited power operation (CPT) modes, and the energy storage DC-DC converter has constant voltage / constant current charge / discharge switching function.

5. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 1, characterized in that: The 750V DC bus platform adopts a three-level flexible DC voltage adaptation, which converts the voltage from DC750V to DC375V and from DC375V to DC48V.

6. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 1, characterized in that: The control cabinet includes an intelligent policy controller, a local monitoring station, and an industrial switch.

7. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 6, characterized in that: The intelligent strategy controller includes three operating modes: optical storage priority, V2G compensation, and off-grid islanding.

8. A multi-port adjustable photovoltaic-storage-DC-flexible integrated energy power supply system according to claim 6, characterized in that: The industrial switch communicates with the upper-layer platform via the Modbus TCP / IP protocol.

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