Optical storage and charging integrated system

Abstract

The utility model discloses a light storage and charging integrated system, and relates to the field of energy storage systems and loads. The system comprises a photovoltaic unit, an energy storage unit, an alternating current bus, a grid-connected inverter and an alternating current load. According to the utility model, the photovoltaic energy is stored in the energy storage system without alternating current conversion, so that the battery has higher energy efficiency compared with an alternating current bus scheme, the DCDC is directly used for charging the battery, the battery pack directly meets the requirements of a grid-connected inverter through the voltage of the battery pack, and the energy efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage, and particularly relates to a photovoltaic energy storage charging integrated system. Background Art

[0002] Energy storage technology, especially electrochemical energy storage technology, has developed rapidly in recent years due to features such as peak-valley regulation and improvement of power system stability. To a certain extent, an energy storage system can solve the problems brought by the unstable output power of new energy power generation such as photovoltaic power and wind power, and expand the grid connection of new energy.

[0003] In the current energy storage system industry, AC bus coupling is adopted for photovoltaic, which is a relatively common solution at present. As Figure 1 shown, in which, the energy storage system, the load and the photovoltaic power generation are relatively independent and are connected to the same AC bus. The load draws energy from the AC grid for charging electric vehicles. The energy storage system stores energy during the low electricity price period and releases energy during the high electricity price period. The energy storage system and the load are two independent branches, and essentially two sets of equipment connected to the AC grid. For the load, there are large energy losses through two-stage conversion from AC to DC and then from DC to DC. For the energy storage system, when storing energy, it changes from AC to DC and stores it in the energy storage battery, and when discharging, it converts the energy in the battery back to AC. The energy undergoes multiple conversions from the energy storage system to the load, resulting in large energy losses and reducing the benefits of the energy storage system. Summary of the Utility Model

[0004] To overcome the above drawbacks, the purpose of the utility model is to provide a photovoltaic energy storage charging integrated system to solve the problem that in the AC bus energy storage system mentioned in the above background art, when accessing energy storage, it needs to go through the AC bus and needs to perform another AC / DC coupling to achieve the energy storage solution, which will cause certain losses.

[0005] To achieve the above purpose, the technical solution adopted by the utility model is a photovoltaic energy storage charging integrated system, including:

[0006] A photovoltaic unit, which is used for generating direct current through photovoltaic power generation.

[0007] An energy storage unit, the energy storage unit includes a battery. The battery is used for storing and releasing energy and is connected to the photovoltaic unit.

[0008] An AC bus, which is connected to the power grid and is used for providing an AC power supply.

[0009] A grid-connected inverter, which is respectively connected to the battery and the AC bus, and is used for converting direct current into alternating current, so that the energy of the photovoltaic can be stored in the energy storage system, directly using DCDC for battery charging, and outputting to the public power grid.

[0010] An AC load, which is connected to the AC bus and used for power supply and drive.

[0011] Furthermore, the energy storage unit further includes a BMS system. The BMS system is connected in series with the battery and includes a bottom-layer battery management unit, a middle-layer aggregation unit, and an upper-layer management system, and is used for battery management.

[0012] Furthermore, the energy storage unit further includes an MPPT controller. The input end of the MPPT controller is connected to the photovoltaic unit, and the output end is connected to the grid-connected inverter. The BMS system and the battery are connected to the output end of the MPPT controller.

[0013] Furthermore, the battery is formed by connecting multiple battery packs in series and parallel according to system requirements, and can meet the voltage and power requirements.

[0014] Furthermore, the integrated photovoltaic energy storage and charging system further includes a dispatching center, an energy management system, and a monitoring platform. The dispatching center, the energy management system, and the monitoring platform are used for real-time monitoring, command, and control of the operation of the power system, and can judge, make decisions, and give commands on the current operating conditions and expected changes of the power system.

[0015] Furthermore, the integrated photovoltaic energy storage and charging system further includes an industrial CT detection system. The industrial CT detection system includes an X-ray tomography imaging device and is used for detecting the battery.

[0016] Furthermore, the integrated photovoltaic energy storage and charging system further includes a 4G and WIFI communication system.

[0017] The integrated photovoltaic energy storage and charging system provided by the present utility model can directly store the energy of the photovoltaic into the energy storage system without converting to AC, making the battery more energy-efficient compared to the energy storage scheme with an AC bus. The battery is directly charged using DCDC, and the battery pack directly meets the requirements of the grid-connected inverter through its own voltage, improving the energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of an energy storage system solution with a shared AC bus in the prior art;

[0019] Figure 2 Schematic diagram of an embodiment of an integrated photovoltaic energy storage and charging system of the present utility model Figure 1 ;

[0020] Figure 3 Schematic diagram of an embodiment of an integrated photovoltaic energy storage and charging system of the present utility model Figure 2 ;

[0021] In the figure:

[0022] 1. Photovoltaic unit; 2. Energy storage unit; 3. Grid-connected inverter; 4. AC load; 7. Power grid; 8. ATS; 9. Distribution box. Specific embodiments

[0023] The following describes in detail the preferred embodiments of the present invention with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0024] Reference Figures 2 to 3 , Figure 2 shows a schematic diagram of an embodiment of an integrated photovoltaic energy storage and charging system provided by an embodiment of the present invention Figure 1 ; Figure 3 shows a schematic diagram of an embodiment of an integrated photovoltaic energy storage and charging system provided by an embodiment of the present invention Figure 2 .

[0025] As Figures 2 to 3 shown, the technical solution adopted by the present invention is an integrated photovoltaic energy storage and charging system, including a photovoltaic unit 1, an energy storage unit 2, an AC bus, a grid-connected inverter 3, and an AC load 4.

[0026] Photovoltaic unit 1, the photovoltaic unit 1 is used for photovoltaic power generation to generate direct current.

[0027] Energy storage unit 2, the energy storage unit 2 includes a battery. The battery is used for energy storage and release and is connected to the photovoltaic unit 1.

[0028] AC bus, connected to the power grid 7, is used to provide AC power.

[0029] Grid-connected inverter 3, the grid-connected inverter 3 is respectively connected to the battery and the AC bus, and is used to convert direct current into alternating current, so that the energy of the photovoltaic can be stored in the energy storage system, directly use DCDC for battery charging, and output to the public power grid 7.

[0030] AC load 4, the AC load 4 is connected to the AC bus and is used for power supply drive.

[0031] Exemplarily, the integrated photovoltaic energy storage and charging system provided by the present invention can directly store the energy of the photovoltaic in the energy storage system without converting to AC, making the battery more energy-efficient compared to the AC bus scheme for energy storage, directly using DCDC for battery charging, and enabling the battery pack to directly meet the requirements of the grid-connected inverter 3 through its own voltage, improving energy efficiency.

[0032] The grid-tie inverter 3 (GTI) is a special inverter mainly used to convert the direct current generated by renewable energy systems such as solar photovoltaic panels and wind turbines into alternating current and output it to the public grid 7. The grid-tie inverter 3 can synchronize with the frequency and phase of the grid 7, so the output alternating current can return to the mains grid 7. The grid-tie inverter 3 can not only feed the excess power into the grid 7 to achieve energy sharing and improve the utilization efficiency of renewable energy, but also monitor information such as the voltage, current and power of the system and protect it, such as grid-connected island protection, low-voltage ride-through, over-voltage protection, etc., to ensure the stable operation of the system.

[0033] Reference Figure 3 , an ATS automatic transfer switch is connected in series between the grid-tie inverter and the AC load. The AC load can be connected to the grid through the ATS automatic transfer switch and the distribution box to switch between the two power supply channels through the ATS automatic transfer switch to ensure the normal operation of the AC load.

[0034] In some embodiments, reference Figures 2 to 3 As shown, the energy storage unit 2 further includes a BMS system. The BMS system is connected in series with the battery and includes a bottom-layer battery management unit, an intermediate-layer aggregation unit, and an upper-layer management system for battery management.

[0035] Exemplarily, the BMS system (battery management system) is a system used to intelligently manage each battery unit and monitor the state of the battery. By collecting and calculating parameters such as voltage, current, and temperature, it can control the charging and discharging process of the battery, and can achieve the protection of the battery and improve the comprehensive performance of the battery.

[0036] In some embodiments, reference Figures 2 to 3 As shown, the energy storage unit 2 further includes an MPPT controller. The input end of the MPPT controller is connected to the photovoltaic unit 1, and the output end is connected to the grid-tie inverter 3. The BMS system and the battery are connected to the output end of the MPPT controller.

[0037] Exemplarily, the MPPT controller can detect the generated voltage of the solar panel in real time and track the maximum voltage and current value (VI), so that the system can charge the battery with the maximum power output. Applied to the solar photovoltaic system, it coordinates the work of the solar panel, the battery, and the load, and is the brain of the photovoltaic system.

[0038] In some embodiments, reference Figures 2 to 3 As shown, the battery is formed by connecting multiple battery packs in series and parallel according to the system requirements, and can meet the voltage and power requirements.

[0039] In some embodiments, reference Figures 2 to 3As shown in the figure, the integrated photovoltaic energy storage and charging system further includes a dispatching center, an energy management system, and a monitoring platform. The dispatching center, the energy management system, and the monitoring platform are used to monitor, command, and control the operation of the power system in real time, and can judge, make decisions, and give commands on the current operating conditions and expected changes of the power system.

[0040] Exemplarily, with the continuous development of the power industry, isolated power systems are gradually evolving into jointly and centrally controlled power systems. The larger the scale of the power system, the more complex the monitoring and control functions become, so complex information transmission equipment is needed to centralize the information of the entire system. As the operating complexity increases and the amount of information grows, it is often difficult for dispatchers to make timely and correct judgments. The dispatching center is equipped with an online dispatching computer and a management computer, and completes the analysis, calculation, monitoring, and control of the entire system through a man-machine dialogue method. The energy management system, abbreviated as EMS, is a collection of software and hardware used to monitor, control, analyze, and optimize energy systems. It realizes the efficient management and optimal allocation of energy through real-time monitoring and intelligent control of all links in energy production, distribution, and consumption.

[0041] In some embodiments, referring to Figures 2 to 3 As shown in the figure, the integrated photovoltaic energy storage and charging system further includes an industrial CT detection system. The industrial CT detection system includes an X-ray tomography imaging device for detecting batteries.

[0042] Exemplarily, in a battery energy storage system, lithium-ion batteries are an important research direction. It generally consists of many single batteries, and each single battery can generate a voltage of several volts. Each battery unit has two electrodes, and lithium ions in the battery are exchanged between the two electrodes. Therefore, microscale analysis of the chemical composition on the electrodes is a key step in improving battery performance. Traditional material analysis methods usually require destroying the sample and do not allow monitoring of battery changes during charge and discharge cycles. In addition, traditional technologies can only provide two-dimensional information and cannot analyze at the three-dimensional scale of parts. The industrial CT detection system visualizes and monitors the process of electrode failure during the charge and discharge cycle of the battery through an X-ray tomography imaging device.

[0043] In some embodiments, referring to Figures 2 to 3 As shown in the figure, the integrated photovoltaic energy storage and charging system further includes a 4G and WIFI communication system.

[0044] Exemplarily, in the integrated photovoltaic energy storage and charging system, the dispatching center, the energy management system, the monitoring platform, the battery, the grid-connected inverter 3, and the photovoltaic modules can transmit information through the 4G and WIFI communication systems, simplifying the overall structure and facilitating flat management. For example, the battery management system (BMS) collects battery pack data and uploads it to the energy management system (EMS) through the 4G and WIFI communication systems and accepts its dispatching control.

[0045] The above embodiments are only for illustrating the technical concept and features of the present utility model. The purpose is to enable those who are familiar with this technology to understand the content of the present utility model and implement it, and it should not be used to limit the protection scope of the present utility model. Any equivalent changes or modifications made according to the spirit and essence of the present utility model should be covered within the protection scope of the present utility model.

Claims

1. A photovoltaic storage and charging integrated system, characterized in that: include: A photovoltaic unit, wherein the photovoltaic unit is used for photovoltaic power generation to generate direct current; An energy storage unit, the energy storage unit comprising a battery; the battery is used for storing and releasing energy and is connected to the photovoltaic unit; AC busbar, connected to the power grid, used to provide AC power; A grid-connected inverter, which is connected to the battery and the AC bus, respectively, and is used to convert direct current into alternating current, so that photovoltaic energy can be stored in the energy storage system, the battery can be charged directly using DCDC, and then output to the public power grid; An AC load is connected to the AC bus for power supply and driving.

2. The integrated photovoltaic storage and charging system according to claim 1, characterized in that: The energy storage unit also includes a BMS system; the BMS system is connected in series with the battery, and includes a bottom-level battery management unit, a middle-level aggregation unit, and an upper-level management system for managing the battery.

3. The integrated photovoltaic storage and charging system according to claim 2, characterized in that: The energy storage unit also includes an MPPT controller; the input end of the MPPT controller is connected to the photovoltaic unit, and the output end is connected to the grid-connected inverter; the BMS system and the battery are connected to the output end of the MPPT controller.

4. The integrated photovoltaic storage and charging system according to claim 1, characterized in that: The battery consists of multiple battery packs connected in series or in parallel according to system requirements, and can meet voltage and power requirements.

5. The integrated photovoltaic storage and charging system according to claim 1, characterized in that: It also includes a dispatching center, an energy management system and a monitoring platform; the dispatching center, energy management system and monitoring platform are used to monitor, command and control the operation of the power system in real time, and can judge, make decisions and command the current operating status and expected changes of the power system.

6. The integrated photovoltaic storage and charging system according to claim 1, characterized in that: It also includes an industrial CT detection system; the industrial CT detection system includes an X-ray tomography imaging device for detecting the battery.

7. The integrated photovoltaic storage and charging system according to claim 1, characterized in that: It also includes 4G and WIFI communication systems.

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