Photovoltaic storage, charging and discharging integrated teaching aid

Abstract

The application discloses a photovoltaic storage and charging integrated teaching aid and relates to the technical field of teaching and practical training equipment. The photovoltaic storage and charging integrated teaching aid comprises a photovoltaic power generation module, a storage module, a direct-current voltage-boosting and filtering module, an inverter module, an electric energy metering module and a load module. The photovoltaic power generation module is used for converting light energy into direct-current power output. The storage module is connected with a power grid. The direct-current voltage-boosting and filtering module is provided with two direct-current voltage-boosting branches, each of which comprises a direct-current filtering unit and a boost voltage-boosting unit. The two boost voltage-boosting units are connected in parallel to a same direct-current bus. The input ends of the two direct-current voltage-boosting branches are connected with the photovoltaic power generation module and the storage module respectively. The inverter module is connected with the direct-current voltage-boosting and filtering module through the direct-current bus. The electric energy metering module is connected between the output end of the inverter module and the power grid access end. The load module is connected to the output end of the inverter module and the power grid access end through a switch. The photovoltaic storage and charging integrated teaching aid has the advantages of high integration, small occupied area, rich teaching scenes, simple operation, complete display of the whole process of photovoltaic power generation, direct-current voltage-boosting and energy storage, inverter grid connection and load power supply, and support for demonstration teaching of two typical operation modes.

Description

Technical Field

[0001] This invention relates to the field of teaching and training equipment technology, and in particular to a photovoltaic energy storage, charging and discharging integrated teaching tool. Background Technology

[0002] With the rapid development of new energy technologies, photovoltaic power generation has been widely used in rural electricity substitution and distributed energy fields. However, there is a relative lack of teaching and training equipment for photovoltaic power generation, energy storage, and integrated charge-discharge systems, and existing equipment and teaching methods are insufficient to meet the needs of improving employees' operation and maintenance skills.

[0003] Currently, photovoltaic power generation-related teaching and training mainly face the following problems: First, training venues are limited. Traditional photovoltaic teaching platforms typically require a large number of photovoltaic panels, occupying a large area, which is not conducive to teaching in limited classroom or training room spaces. Due to the large number of photovoltaic panels and the complexity of the system, photovoltaic storage and dissipation simulation is difficult during training, and there is a lack of effective means. Second, equipment applicability is insufficient. Most existing photovoltaic teaching equipment is designed for universities or research institutions, with complex systems and high operating thresholds. However, the on-site personnel engaged in rural power substitution are mostly power supply station employees with generally low educational levels, making it difficult for them to master relevant skills through pure theoretical learning. Training equipment that closely integrates with practical operation is needed. Third, scenario simulation capabilities are weak. Existing teaching equipment often focuses only on a single aspect of photovoltaic power generation and cannot fully demonstrate the entire process of integrated operation of photovoltaic power generation, energy storage, charging and discharging, and load power consumption. It is difficult to simulate the actual application in typical power substitution scenarios such as rural livestock farmers.

[0004] Existing teaching aids focus on demonstrating the topology of wind-solar hybrid systems, but lack the ability to integrate the switching between two typical working modes: self-consumption and grid connection of photovoltaic power generation and energy storage bidirectional DC-AC converters. They also fail to fully present the entire process of "generation-charging-storage-use" in rural power substitution scenarios, and fail to integrate the entire photovoltaic charging, storage and discharging process into a compact device. Furthermore, they lack teaching demonstrations of core circuits such as DC boost and inverter harmonic suppression.

[0005] Therefore, proposing an integrated photovoltaic energy storage, charging, and discharging teaching tool to solve the difficulties existing in the current technology is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a photovoltaic energy storage, charging and discharging integrated teaching tool, which has high integration, small footprint, rich teaching scenarios, and simple operation. It can fully demonstrate the entire process of photovoltaic power generation, DC boost energy storage, inverter grid connection and load power supply, and supports demonstration teaching of two typical operating modes.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A photovoltaic energy storage, charging, and discharging integrated teaching tool includes: A photovoltaic power generation module includes at least two photovoltaic panels connected in series, used to convert light energy into direct current output; Energy storage modules are connected to the power grid to store electrical energy from the grid, providing a continuous and stable power supply when photovoltaic power generation is insufficient or when the power grid is interrupted. The DC boost filter module includes: two DC boost branches; each DC boost branch includes: a DC filter unit and a boost unit; the output terminals of the two boost units are connected in parallel to the same DC bus; the input terminal of the first DC boost branch is connected to the output terminal of the photovoltaic power generation module, and the input terminal of the second DC boost branch is connected to the output terminal of the energy storage module. The inverter module, connected to the DC boost filter module via the DC bus, includes a full-bridge inverter circuit and an AC filter circuit. The full-bridge inverter circuit converts the DC power on the DC bus into AC power and uses an SVPWM control strategy for harmonic suppression. The AC filter circuit filters the output of the full-bridge inverter circuit and provides AC output. The power metering module is connected between the output terminal of the inverter module and the grid access terminal to monitor and display the grid-connected power and the self-generated and self-consumed power. The load module, connected to the output of the inverter module and the grid connection via a switch, is used to demonstrate the operation of loads powered by photovoltaic power and grid power.

[0008] Among the aforementioned teaching aids, the photovoltaic power generation module can be optionally equipped with a photovoltaic panel model of SPP15P60, with a maximum power of 315W per panel.

[0009] The aforementioned teaching aids may optionally include an energy storage module, comprising an energy storage battery pack consisting of five batteries with a nominal voltage of 12V connected in series, wherein the rated DC voltage of the energy storage battery pack is 60V.

[0010] The aforementioned teaching aids may optionally include an energy storage module, which may also include a bidirectional DC-AC converter. The energy storage module is connected to the power grid through the bidirectional DC-AC converter for charging the energy storage module from the power grid when the power grid is normal.

[0011] The aforementioned teaching aids may include, optionally, a DC boost filter module in which the DC filter unit includes a common-mode inductor and an X capacitor, and a boost unit includes an IGBT device, a boost inductor, a fast recovery diode, and a bus capacitor. The IGBT device is model number 40N120.

[0012] The aforementioned teaching aids may include an inverter module with a DC bus input voltage range of 55-82V and an input current range of 0-20A; and an AC output voltage range of 210-230V and an output current range of 0-10A. The inverter module is encapsulated in a three-phase inverter housing and achieves 220V AC output through single-phase wiring.

[0013] The aforementioned teaching aids may include optional load modules, such as lighting loads, ventilation loads, and heating loads, to meet the power needs of various scenarios. When the load power of the load module is greater than the output power of the photovoltaic power generation module, the power grid and the photovoltaic power generation module supply power to the load module simultaneously.

[0014] Of the aforementioned teaching aids, one option is a photovoltaic energy storage, charging, and discharging integrated teaching aid, which includes two working modes: In grid connection mode, the DC power output by the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus. The power on the DC bus is converted into AC power by the inverter module and is preferentially supplied to the load module. The surplus power is fed into the grid through the power metering module. In the self-consumption mode, the DC power output from the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus and stored in the energy storage module. When the grid fails, the energy storage module supplies power to the DC bus through the second DC boost branch. The electrical energy on the DC bus is converted into AC power by the inverter module and then supplied to the load module. The charging control of the energy storage battery pack is realized through the MPPT controller.

[0015] As can be seen from the above technical solution, compared with the prior art, the present invention provides a photovoltaic energy storage, charging and discharging integrated teaching tool, which has the following beneficial effects: This invention integrates all functions such as photovoltaic power generation, DC boost, energy storage, inverter, metering, and load control into a single unit. Teaching demonstrations can be completed using only a small number of photovoltaic panels, making it particularly suitable for training environments with limited space. This invention supports demonstrations of two typical operating modes: grid connection and self-consumption. It can fully demonstrate the entire photovoltaic generation-charging-storage-consumption process and simulate various typical electricity substitution scenarios (heating, ventilation, lighting, etc.), providing excellent teaching intuitiveness. The invention features a simplified system design, employing modular designs for boost, voltage regulation charging, and inverter operation. This facilitates practical training for students in wiring photovoltaic panels, inverters and parameter control, energy storage devices, and loads, making it particularly suitable for training personnel such as power supply station employees with generally low levels of education. This invention uses a full-bridge inverter circuit combined with SVPWM small vector control for harmonic suppression, and outputs stable AC power after AC filtering, meeting the power quality requirements for teaching demonstrations. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 This invention provides a structural diagram of an integrated photovoltaic energy storage, charging, and discharging teaching tool. Figure 2 A physical image of a photovoltaic energy storage, charging, and discharging integrated teaching aid provided in a specific embodiment of the present invention; Figure 3 The waveform diagram of AC output voltage and current with inductive load provided in a specific embodiment of the present invention; Figure 4 The simulation waveform diagram of AC no-load output is shown in a specific embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Reference Figure 1 As shown, this invention discloses a photovoltaic energy storage, charging, and discharging integrated teaching aid, comprising: A photovoltaic power generation module includes at least two photovoltaic panels connected in series, used to convert light energy into direct current output; Energy storage modules are connected to the power grid to store electrical energy from the grid, providing a continuous and stable power supply when photovoltaic power generation is insufficient or when the power grid is interrupted. The DC boost filter module includes: two DC boost branches; each DC boost branch includes: a DC filter unit and a boost unit; the output terminals of the two boost units are connected in parallel to the same DC bus; the input terminal of the first DC boost branch is connected to the output terminal of the photovoltaic power generation module, and the input terminal of the second DC boost branch is connected to the output terminal of the energy storage module. The inverter module, connected to the DC boost filter module via the DC bus, includes a full-bridge inverter circuit and an AC filter circuit. The full-bridge inverter circuit converts the DC power on the DC bus into AC power and uses an SVPWM control strategy for harmonic suppression. The AC filter circuit filters the output of the full-bridge inverter circuit and provides AC output. The power metering module is connected between the output terminal of the inverter module and the grid access terminal to monitor and display the grid-connected power and the self-generated and self-consumed power. The load module, connected to the output of the inverter module and the grid connection via a switch, is used to demonstrate the operation of loads powered by photovoltaic power and grid power.

[0020] Furthermore, in the photovoltaic power generation module, two photovoltaic panels (model SPP15P60 with a maximum power of 315W, an optimal operating voltage of 32.2V, and an optimal operating current of 9.79A) are connected in series. This design can improve the system's power generation efficiency and output power, thereby meeting the user's energy needs.

[0021] Furthermore, the energy storage module includes a battery pack consisting of five batteries connected in series with a nominal voltage of 12V. The rated DC voltage of the battery pack is 60V. This design can provide users with a continuous and stable power supply when photovoltaic power generation is insufficient or when the grid experiences a power outage. The energy storage module also includes a bidirectional DC-AC converter. The energy storage module is connected to the grid through the bidirectional DC-AC converter, which is used to charge the energy storage module from the grid when the grid is normal, realizing mutual supplementation and utilization of electrical energy.

[0022] Furthermore, in the DC boost filter module, the DC filter unit includes a common-mode inductor and an X capacitor, and the boost unit includes an IGBT device, a boost inductor, a fast recovery diode, and a bus capacitor. The model number of the IGBT device is 40N120; Common-mode inductors and X capacitors are used to achieve filtering; IGBT devices, boost inductors, fast recovery diodes, and bus capacitors complete the DC boost function; The two boost circuits are each filtered by DC and then pass through the boost circuit to reach the bus. One circuit connects to the solar panel, and the other connects to the battery. This design ensures the stability and reliability of the system.

[0023] Furthermore, in the inverter module, the DC bus input voltage range is 55-82V, and the input current range is 0-20A; the AC output voltage range is 210-230V, and the output current range is 0-10A. The inverter module is encapsulated in a three-phase inverter housing and achieves 220V AC output through single-phase wiring. Furthermore, the full-bridge inverter circuit completes the inversion, and the SVPWM small vector control completes the harmonic suppression. The DC power on the bus is converted into AC power through the full-bridge inverter, and then a stable AC power is output after AC filtering. This design can meet the user's demand for AC power and realize the effective utilization of electrical energy.

[0024] Furthermore, the load modules include lighting loads, ventilation loads, and heating loads, which are used to meet the power needs in various scenarios. When the load power of the load module is greater than the output power of the photovoltaic power generation module, the power grid and the photovoltaic power generation module supply power to the load module at the same time.

[0025] Furthermore, a photovoltaic energy storage, charging, and discharging integrated teaching tool includes two working modes: In grid connection mode, the DC power output by the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus. The power on the DC bus is converted into AC power by the inverter module and is preferentially supplied to the load module. The surplus power is fed into the grid through the power metering module. In the self-consumption mode, the DC power output by the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus and stored in the energy storage module; when the grid fails, the energy storage module supplies power to the DC bus through the second DC boost branch, and the electrical energy on the DC bus is converted into AC power by the inverter module and then supplied to the load module; the charging control of the energy storage battery pack is realized through the MPPT controller. During the day, photovoltaic power generation first supplies the load, and then charges the energy storage battery pack through the MPPT controller. The energy storage module is connected to the grid, and excess power can be fed into the grid. At night, the battery discharges to supply the load, and the grid supplements the shortfall. When the grid fails, the photovoltaic power generation module and the energy storage module can supply power to the load. When the load power is greater than the photovoltaic power generation power, the grid and photovoltaic can supply power to the farmer's load at the same time, achieving a seamless connection between the two modes. Because neither photovoltaic power generation nor load power consumption is stable, the energy balance of the battery system is required.

[0026] In one specific embodiment, refer to Figure 2 As shown, the photovoltaic power generation module consists of two photovoltaic panels connected in series. In this embodiment, the photovoltaic panel used is model SPP15P60, with a maximum power of 315W per panel, an optimal operating voltage of 32.2V, and an optimal operating current of 9.79A. With the two photovoltaic panels connected in series, the rated output voltage is approximately 64.4V, which meets the input requirements of the subsequent DC boost circuit. The design using a small number of photovoltaic panels reduces equipment costs and floor space, making it suitable for environments with limited training space.

[0027] The DC boost filter module includes two DC boost branches (boost branches), corresponding to the photovoltaic power generation input and the energy storage battery input respectively. Each DC boost branch includes a DC filter unit and a boost unit. The DC filter unit consists of a DC common-mode inductor and an X capacitor, used to suppress differential-mode and common-mode interference and improve the power quality of the DC bus. The boost unit includes an IGBT device (40N120), a boost inductor, a fast recovery diode, and a bus capacitor to complete the DC boost function. The outputs of the two boost units are connected in parallel to the same DC bus. The first branch (photovoltaic branch) is connected to the output of the photovoltaic power generation module for MPPT tracking boost of the photovoltaic output. The second branch (energy storage branch) is connected to the energy storage module for charge / discharge boost / buck control of the energy storage battery. The two boost branches share the same bus, realizing coordinated management of photovoltaic energy and energy storage energy. The energy storage module consists of five batteries with a nominal voltage of 12V connected in series. The rated DC voltage is 60V. The energy storage battery pack is directly connected to the DC bus. The DC power generated by the photovoltaic module can be stored in the battery pack through the first boost branch and the controller. When the grid is normal, the battery can also be charged through the bidirectional DC-AC converter. The inverter module includes a full-bridge inverter circuit and an AC filter circuit. The full-bridge inverter circuit converts the DC power on the DC bus into AC power output and uses an SVPWM small vector control strategy to suppress harmonics. The AC power after full-bridge inversion is then filtered by the AC filter circuit to output AC power that meets the requirements of grid connection or load power consumption. In this embodiment, the parameters of the inverter unit are: DC side input voltage range of 55-82V, input current range of 0-20A; AC side output voltage range of 210-230V, output current range of 0-10A, and frequency of 50Hz. The inverter unit is encapsulated in a three-phase inverter housing and achieves 220V AC output through single-phase wiring, used to simulate the demonstration function of "photovoltaic charging and storage". Tested by Detech's professional oscilloscope, the voltage and frequency after filtering and stabilization are within the required range. The AC output voltage and current waveforms with inductive load and the AC no-load output simulation waveforms are as follows: Figure 3 , Figure 4 As shown.

[0028] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0029] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A photovoltaic energy storage, charging, and discharging integrated teaching aid, characterized in that, include: A photovoltaic power generation module includes at least two photovoltaic panels connected in series, used to convert light energy into direct current output; Energy storage modules are connected to the power grid to store electrical energy from the grid, providing a continuous and stable power supply when photovoltaic power generation is insufficient or when the power grid is interrupted. The DC boost filter module includes: two DC boost branches; each DC boost branch includes: a DC filter unit and a boost unit; the output terminals of the two boost units are connected in parallel to the same DC bus; the input terminal of the first DC boost branch is connected to the output terminal of the photovoltaic power generation module, and the input terminal of the second DC boost branch is connected to the output terminal of the energy storage module. The inverter module, connected to the DC boost filter module via the DC bus, includes a full-bridge inverter circuit and an AC filter circuit. The full-bridge inverter circuit converts the DC power on the DC bus into AC power and uses an SVPWM control strategy for harmonic suppression. The AC filter circuit filters the output of the full-bridge inverter circuit and provides AC output. The power metering module is connected between the output terminal of the inverter module and the grid access terminal to monitor and display the grid-connected power and the self-generated and self-consumed power. The load module, connected to the output of the inverter module and the grid connection via a switch, is used to demonstrate the operation of loads powered by photovoltaic power and grid power.

2. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that, In the photovoltaic power generation module, the photovoltaic panel model is SPP15P60, and the maximum power of a single panel is 315W.

3. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that, The energy storage module includes an energy storage battery pack consisting of five batteries with a nominal voltage of 12V connected in series, and the rated DC voltage of the energy storage battery pack is 60V.

4. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 3, characterized in that, The energy storage module also includes a bidirectional DC-AC converter. The energy storage module is connected to the power grid through the bidirectional DC-AC converter, which is used to charge the energy storage module from the power grid when the power grid is normal.

5. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that, In the DC boost filter module, the DC filter unit includes a common-mode inductor and an X capacitor, and the boost unit includes an IGBT device, a boost inductor, a fast recovery diode, and a bus capacitor. The IGBT device is model number 40N120.

6. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that, In the inverter module, the DC bus input voltage range is 55-82V, and the input current range is 0-20A; the AC output voltage range is 210-230V, and the output current range is 0-10A. The inverter module is encapsulated in a three-phase inverter housing and achieves 220V AC output through single-phase wiring.

7. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that, The load modules include lighting loads, ventilation loads, and heating loads, which are used to meet the power needs of various scenarios. When the load power of the load module is greater than the output power of the photovoltaic power generation module, the power grid and the photovoltaic power generation module supply power to the load module at the same time.

8. The photovoltaic energy storage, charging, and discharging integrated teaching aid according to claim 1, characterized in that... ， A photovoltaic energy storage, charging, and discharging integrated teaching tool includes two working modes: In grid connection mode, the DC power output by the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus. The power on the DC bus is converted into AC power by the inverter module and is preferentially supplied to the load module. The surplus power is fed into the grid through the power metering module. In the self-consumption mode, the DC power output from the photovoltaic power generation module is boosted by the first DC boost branch and then fed into the DC bus and stored in the energy storage module. When the grid fails, the energy storage module supplies power to the DC bus through the second DC boost branch. The electrical energy on the DC bus is converted into AC power by the inverter module and then supplied to the load module. The charging control of the energy storage battery pack is realized through the MPPT controller.

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