Charging pile test system and method based on energy feedback and photovoltaic energy storage

Abstract

The invention discloses a charging pile testing system and method based on energy feedback and photovoltaic energy storage, and belongs to the technical field of charging pile testing. The system comprises a power grid power supply interface module, a photovoltaic assembly module, an energy storage module, a charging pile interface circuit module, a multi-mode test load module, an energy feedback module, a central control module and a data acquisition and analysis module. According to the system, the technical effects of efficient energy feedback, intelligent collaborative management of light storage and charging and multi-mode dynamic scheduling in the charging pile testing process are achieved.

Description

Technical Field

[0001] This application relates to the technical field of charging pile testing, and particularly to a charging pile testing system and method based on energy feedback and photovoltaic energy storage. Background Art

[0002] With the rapid development of two-wheeled electric vehicles, the charging pile, as its core supporting facility, the performance and safety testing thereof has become a key link. In the prior art, the two-wheeled electric vehicle charging pile testing system mainly relies on resistive loads to directly consume electric energy to verify the charging function. For example, the charging process is simulated through a constant resistance load. In addition, some improved solutions attempt to introduce photovoltaic power generation technology. For example, photovoltaic panels are deployed beside the charging pile to directly supply power to the electric vehicle, or an energy storage unit is combined to store excess electric energy. However, these systems generally focus on the verification of basic charging functions, the energy management method is relatively single, and the collaborative ability of photovoltaic and energy storage is limited, and a complete energy cycle system cannot be formed.

[0003] The prior art has the following significant deficiencies: First, the traditional testing system uses the resistive energy consumption method, and the power consumption for a single test is huge and the energy cannot be recovered, resulting in high testing costs and serious heat dissipation problems. Second, most of the existing photovoltaic energy storage charging systems adopt a unidirectional charging mode and lack a two-way energy feedback mechanism, and the excess electric energy generated during the testing process cannot be fed back to the power grid or the energy storage device, causing energy waste. In addition, the existing solutions have insufficient collaborative management ability for photovoltaic power generation and energy storage. For example, the battery management unit of the energy storage module has a single function and cannot dynamically balance the battery state or cope with grid fluctuations; the photovoltaic power generation efficiency is limited by the fixed maximum power point tracking strategy and it is difficult to adapt to complex lighting conditions. Finally, the existing testing system has a low degree of intelligence and lacks the ability of multi-mode collaborative scheduling, resulting in insufficient equipment utilization rate, long testing cycle and low efficiency.

[0004] Therefore, how to achieve efficient energy feedback, intelligent collaborative management of photovoltaic energy storage charging, and multi-mode dynamic scheduling during the charging pile testing process has become a technical problem to be solved urgently. Summary of the Invention

[0005] The embodiments of this application provide a charging pile testing system and method based on energy feedback and photovoltaic energy storage to solve the following technical problems: how to achieve efficient energy feedback, intelligent collaborative management of photovoltaic energy storage charging, and multi-mode dynamic scheduling during the charging pile testing process.

[0006] In a first aspect, an embodiment of the present application provides a charging pile test system based on energy feedback and photovoltaic energy storage, which is applied to the test of charging piles. The charging piles are used to charge two-wheel electric vehicles. The system includes: a grid power supply interface module, which is used to connect to the external grid and receive power supply from the external grid; a photovoltaic module, which is used to convert solar energy into direct current and optimize the output power; an energy storage module, which includes a lithium iron phosphate battery pack, a bidirectional energy storage inverter, a battery management unit, and a DC bus. The bidirectional energy storage inverter is connected to the DC bus and is used to store and release electrical energy; a charging pile interface circuit module, which is used to access the charging pile and interact with the charging pile; a multi-modal test load module, which is used to simulate the load characteristics under different charging conditions; an energy feedback module, which is used to convert the electrical energy of the multi-modal test load module into feedback electrical energy and feed it back to the external grid or the energy storage module; a central control module, which is connected to the photovoltaic module, the energy storage module, the energy feedback module, and the charging pile interface circuit module, and is used to collect data and generate energy distribution control instructions; a data acquisition and analysis module, which is used to record the output parameters of the charging pile, the input parameters of the multi-modal test load module, and the energy feedback efficiency, and generate a performance evaluation report.

[0007] In an implementation manner of the present application, the photovoltaic module includes: a single-crystal photovoltaic panel array, which includes a plurality of single-crystal photovoltaic panels and is used to absorb solar energy; a maximum power point tracking circuit, which adjusts the working voltage and current of the single-crystal photovoltaic panel array based on the preset perturbation observation method; a light intensity sensor, which monitors the ambient light data in real time and transmits it to the central control module; an anti-reverse diode, which is used to prevent current backflow; a fuse, which is used for overload protection; a DC busbar box, which is used to connect the outputs of multiple photovoltaic panels in parallel and then access the DC bus of the energy storage module.

[0008] In an implementation manner of the present application, the energy storage module includes: a lithium iron phosphate battery pack, which includes a plurality of lithium iron phosphate batteries and is used to store electrical energy; a bidirectional energy storage inverter, which is used to switch the charge and discharge states according to the instructions of the central control unit; a battery management unit, which includes a voltage collector, a temperature sensor, and an equalization circuit, and is used to monitor the states of the plurality of lithium iron phosphate batteries and make adjustments; a heat dissipation air duct and a temperature control device, which are used to adjust the heat dissipation intensity according to the temperature of the lithium iron phosphate battery pack; an energy storage status display screen, which is used to display the state of charge, health status, and charge and discharge power of the lithium iron phosphate battery pack.

[0009] In an implementation manner of the present application, the energy feedback module includes: a bidirectional DC / DC converter for boosting the low-voltage direct current output from the interface of the charging pile to high-voltage direct current; a bidirectional AC / DC inverter connected to the grid power supply interface module for converting the high-voltage direct current into alternating current with the same frequency and phase as the external grid; a phase synchronization detection circuit for monitoring the voltage and frequency of the external grid to adjust the phase of the inverter output for grid connection with the external grid; an energy feedback changeover switch for selecting to feed the electric energy back to the grid or the energy storage module according to the state of charge of the energy storage module; and an electric energy metering unit for recording the power and cumulative total amount of the fed-back electric energy.

[0010] In an implementation manner of the present application, the multi-modal test load module includes: an adjustable constant-resistance load for adjusting the resistance value to simulate a static load; a dynamic electronic load controller for generating a dynamic load waveform based on a preset riding condition curve to simulate the actual charging power fluctuation; a battery simulator for simulating the charging response characteristics of different battery types; a load parameter acquisition unit for capturing voltage, current and power data and transmitting them to the data acquisition and analysis module; and a multiplexer for switching the combined modes of the adjustable constant-resistance load, the dynamic electronic load controller and the battery simulator.

[0011] In an implementation manner of the present application, the central control module includes: a communication interface matrix unit for connecting to and performing data interaction with the photovoltaic module, the energy storage module, the energy feedback module and the charging pile interface circuit module; a data processing unit for calculating the power generation power of the photovoltaic module, the state of charge of the energy storage module and the required power of the charging pile; a control strategy generation unit for allocating the power supply ratios of the photovoltaic module, the energy storage module and the external grid based on a preset linear programming algorithm; a fault diagnosis unit for detecting the abnormal states of the photovoltaic module, the energy storage module, the energy feedback module and the charging pile interface circuit module and triggering a protection mechanism; and a human-machine interface for providing functions of working mode selection, parameter setting and operation state display.

[0012] In a second aspect, the embodiments of the present application further provide a charging pile testing method based on energy feedback and photovoltaic energy storage, which is applied to the above-mentioned charging pile testing system based on energy feedback and photovoltaic energy storage. The method includes: initializing operating parameters and establishing communication connections among the grid power supply interface module, the photovoltaic module, the energy storage module, the energy feedback module, and the central control module; selecting a coordinated operation mode based on user input or preset conditions; where the coordinated operation mode includes a photovoltaic priority mode, a hybrid power supply mode, and an energy storage island mode; if the photovoltaic priority mode is selected, collect the power generation power data of the photovoltaic module, and preferentially call the output power of the photovoltaic module to supply power to the charging pile. If the power generation power of the photovoltaic module is insufficient, call the stored electric energy of the energy storage module to supplement the power supply. If the total power is insufficient, call the grid power supply interface module to supply power to the charging pile; if the hybrid power supply mode is selected, allocate the power generation power of the photovoltaic module, the discharge power of the energy storage module, and the supplementary power of the grid power supply interface module, and adjust the proportion of the power generation power, the discharge power, and the supplementary power based on the real-time power demand of the charging pile; if the energy storage island mode is selected, disconnect the connection of the grid power supply interface module and call the energy storage module to independently supply power to the charging pile; monitor the electric energy consumed by the multi-modal test load module through the energy feedback module, convert the consumed electric energy into recoverable electric energy, and select to feedback it to the external grid or the energy storage module according to the state of charge of the energy storage module; record the output parameters of the charging pile, the input parameters of the test load, and the energy feedback efficiency data through the data acquisition and analysis module, and generate a performance evaluation report including voltage volatility, current stability, and comprehensive energy efficiency ratio; based on the performance evaluation report, optimize the energy distribution strategy through the central control module, and adjust the maximum power point tracking parameters of the photovoltaic module, the charge and discharge rate of the energy storage module, and the switching logic of the energy feedback module.

[0013] In an implementation manner of the present application, if the photovoltaic priority mode is selected, collect the power generation power data of the photovoltaic module, and preferentially call the output power of the photovoltaic module to supply power to the charging pile. If the power generation power of the photovoltaic module is insufficient, call the stored electric energy of the energy storage module to supplement the power supply. If the total power is insufficient, call the grid power supply interface module to supply power to the charging pile. Specifically, it includes: real-time collecting ambient light data through a light intensity sensor, and adjusting the output voltage and current of the photovoltaic module through a maximum power point tracking circuit to make the photovoltaic module work at the maximum power point; comparing the output power of the photovoltaic module with the demand power of the charging pile. If the photovoltaic output power is greater than or equal to the demand power, preferentially use the photovoltaic module to supply power; if the photovoltaic output power is less than the demand power, call the stored electric energy of the energy storage module to supplement the power supply; if the sum of the photovoltaic output power and the output power of the energy storage module is less than the demand power, call the grid power supply interface module to make up the power supply; record and upload the power supply proportion of the photovoltaic module, the power supply proportion of the energy storage module, and the supplementary power proportion of the external grid to the central control module.

[0014] In one implementation of the present application, if the hybrid power supply mode is selected, the power generation power of the photovoltaic module, the discharge power of the energy storage module, and the supplementary power of the grid power interface module are allocated, and the ratios of the power generation power, the discharge power, and the supplementary power are adjusted based on the real-time power demand of the charging pile. Specifically, it includes: collecting the power generation power of the photovoltaic module, the state of charge of the energy storage module, and the power demand of the charging pile, and calculating the optimal output ratios of the photovoltaic module, the energy storage module, and the external power grid through a linear programming algorithm; if the power generation power of the photovoltaic module exceeds the power demand of the charging pile, determining the first excess electric energy and storing the first excess electric energy in the energy storage module through a bi-directional energy storage converter; where the excess electric energy is the power generation power of the photovoltaic module minus the power demand of the charging pile; if the state of charge of the energy storage module reaches the preset upper limit, determining the second excess electric energy, and feeding back the second excess electric energy to the external power grid through an energy feedback module, and recording the real-time power and total amount of the feedback electric energy; adjusting the output powers of the photovoltaic module, the energy storage module, and the grid power interface module; when abnormal fluctuations in the grid voltage of the external power grid are detected, switching to the independent power supply mode of the energy storage module and triggering a grid anomaly alarm.

[0015] In one implementation of the present application, if the energy storage island mode is selected, the connection of the grid power interface module is cut off, and the energy storage module is called to independently supply power to the charging pile. Specifically, it includes: cutting off the connection between the charging pile and the grid power interface module, and calling the energy storage module to independently supply power to the charging pile; monitoring the state of charge of the energy storage module, and triggering an alarm and restricting the maximum output power of the charging pile if it is lower than the preset threshold; adjusting the energy storage module through the balancing circuit of the battery management unit; recording the charge and discharge cycle times and capacity attenuation data of the energy storage module to generate a battery health assessment report.

[0016] A charging pile test system and method based on energy feedback and photovoltaic energy storage provided by an embodiment of the present application at least have the following technical effects: The energy utilization rate is significantly improved: The electric energy consumed by the multi-modal test load module is converted into recoverable electric energy through the energy feedback module, and it is dynamically selected to be fed back to the power grid or the energy storage module, effectively reducing the energy waste problem of traditional tests of the present application and at the same time reducing the test cost.

[0017] Renewable energy is efficiently utilized: The photovoltaic module adopts a maximum power point tracking circuit, and combines the perturbation observation method to optimize the working voltage and current of the photovoltaic panel in real time, ensuring the maximum solar power output under different light conditions; the energy storage module realizes dynamic charge and discharge control through a bi-directional energy storage converter and a battery management unit, further improving the utilization rate of photovoltaic power generation.

[0018] Enhanced multi - mode collaboration and dynamic scheduling capabilities: This application supports the photovoltaic - priority mode, hybrid power - supply mode, and energy - storage island mode. The central control module dynamically allocates the power supply ratios of photovoltaic, energy storage, and the power grid based on the linear - programming algorithm, significantly enhancing the adaptability to different test scenarios. Meanwhile, it optimizes the energy - distribution strategy to ensure the continuity and stability of the charging - pile power demand.

[0019] Improved test intelligence and automation levels: The data - acquisition and analysis module records the output parameters of the charging pile, the input parameters of the multi - modal test load module, and the energy - feedback efficiency in real time, generating an evaluation report containing indicators such as voltage volatility and current stability. The central control module automatically optimizes the energy - distribution strategy according to the evaluation results, adjusts the photovoltaic - tracking parameters and the energy - storage charge - discharge rate, improving the test efficiency and equipment utilization rate.

[0020] Guaranteed safety and reliability: The energy - storage module is equipped with a battery - management unit and a temperature - control device, which monitors the battery state in real time and performs dynamic - balancing management, effectively extending the battery life. The energy - feedback module realizes seamless grid connection through a phase - synchronization detection circuit, combined with over - voltage and over - current protection functions, ensuring the safety of the operation of this application and grid compatibility to a certain extent. Description of the Drawings

[0021] The drawings described herein are used to provide a further understanding of this application and form a part of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings: Figure 1 It is a schematic diagram of a charging - pile test system based on energy feedback and photovoltaic energy storage provided by an embodiment of this application; Figure 2 It is a flowchart of a charging - pile test method based on energy feedback and photovoltaic energy storage provided by an embodiment of this application. Detailed Embodiments

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0023] The embodiments of this application provide a charging - pile test system and method based on energy feedback and photovoltaic energy storage to solve the following technical problems: how to achieve efficient energy feedback, intelligent collaborative management of photovoltaics, energy storage, and charging, and multi - mode dynamic scheduling during the charging - pile test process.

[0024] The technical solutions proposed in the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0025] Figure 1 A schematic diagram of a charging pile test system based on energy feedback and photovoltaic energy storage provided by an embodiment of the present application. As Figure 1 shown, a charging pile test system based on energy feedback and photovoltaic energy storage provided by an embodiment of the present application is applied to the test of a charging pile. The charging pile is used to charge two-wheeled electric vehicles and includes: A grid power interface module for connecting to an external grid and receiving power supply from the external grid; A photovoltaic module for converting solar energy into direct current and optimizing the output power; A energy storage module including a lithium iron phosphate battery pack, a bidirectional energy storage inverter, a battery management unit, and a DC bus. The bidirectional energy storage inverter is connected to the DC bus and is used to store and release electrical energy; A charging pile interface circuit module for accessing the charging pile and interacting with the charging pile; A multi-modal test load module for simulating the load characteristics under different charging conditions; An energy feedback module for converting the electrical energy of the multi-modal test load module into feedback electrical energy and feeding it back to the external grid or the energy storage module; A central control module connected to the photovoltaic module, the energy storage module, the energy feedback module, and the charging pile interface circuit module, for collecting data and generating energy distribution control instructions; A data acquisition and analysis module for recording the output parameters of the charging pile, the input parameters of the multi-modal test load module, and the energy feedback efficiency, and generating a performance evaluation report.

[0026] The photovoltaic module includes: A single-crystal photovoltaic panel array including a plurality of single-crystal photovoltaic panels for absorbing solar energy; A maximum power point tracking circuit for adjusting the operating voltage and current of the single-crystal photovoltaic panel array based on the preset perturbation observation method; A light intensity sensor for real-time monitoring of ambient light data and transmitting it to the central control module; An anti-reverse diode for preventing current backflow; A fuse for overcurrent protection; A DC busbar box for converging the outputs of multiple photovoltaic panels and connecting them to the DC bus of the energy storage module.

[0027] The energy storage module includes: A lithium iron phosphate battery pack including a plurality of lithium iron phosphate batteries for storing electrical energy; A bidirectional energy storage inverter for switching the charge and discharge states according to the instructions of the central control unit; The battery management unit includes a voltage collector, a temperature sensor, and a balancing circuit, and is used to monitor the status of multiple lithium iron phosphate batteries and make adjustments; The heat dissipation air duct and the temperature control device are used to adjust the heat dissipation intensity according to the temperature of the lithium iron phosphate battery pack; The energy storage status display screen is used to display the state of charge, health, and charge and discharge power of the lithium iron phosphate battery pack.

[0028] The energy feedback module includes: A bidirectional DC / DC converter, which is used to boost the low-voltage direct current output from the interface of the charging pile to high-voltage direct current; A bidirectional AC / DC inverter, which is connected to the grid power interface module and is used to convert high-voltage direct current into alternating current with the same frequency and phase as the external grid; A phase synchronization detection circuit, which is used to monitor the voltage and frequency of the external grid to adjust the phase of the inverter output and be connected to the external grid; An energy feedback switch, which is used to select whether to feed back electric energy to the grid or the energy storage module according to the state of charge of the energy storage module; An electric energy metering unit, which is used to record the power and cumulative total amount of the feedback electric energy.

[0029] The multi-modal test load module includes: An adjustable constant resistance load, which is used to adjust the resistance value to simulate a static load; A dynamic electronic load controller, which generates a dynamic load waveform based on a preset riding condition curve to simulate the actual charging power fluctuation; A battery simulator, which is used to simulate the charging response characteristics of different battery types; A load parameter acquisition unit, which is used to capture voltage, current, and power data and transmit them to the data acquisition and analysis module; A multiplexer switch, which is used to switch the combination modes of the adjustable constant resistance load, the dynamic electronic load controller, and the battery simulator.

[0030] The central control module includes: A communication interface matrix unit, which is used to connect to the photovoltaic module, the energy storage module, the energy feedback module, and the charging pile interface circuit module, and perform data interaction; A data processing unit, which is used to calculate the power generation power of the photovoltaic module, the state of charge of the energy storage module, and the required power of the charging pile; A control strategy generation unit, which is used to allocate the power supply ratios of the photovoltaic module, the energy storage module, and the external grid based on a preset linear programming algorithm; A fault diagnosis unit, which is used to detect the abnormal states of the photovoltaic module, the energy storage module, the energy feedback module, and the charging pile interface circuit module and trigger a protection mechanism; The human - machine interaction interface is used to provide functions of working mode selection, parameter setting, and operating status display.

[0031] Figure 2 This is a charging pile test flow chart provided by an embodiment of the present application based on energy feedback and photovoltaic energy storage. As Figure 2 shown, a charging pile test method provided by an embodiment of the present application specifically includes the following steps: Step 1: Initialize the operating parameters and establish communication connections among the grid power supply interface module, photovoltaic module, energy storage module, energy feedback module, and central control module.

[0032] Initializing the operating parameters includes configuring the basic parameters of each module. For example, the voltage range (such as 220V ± 10%), frequency (50Hz), and maximum power threshold (such as 10kW) of the grid power supply interface module; the initial operating voltage (such as 48V) and current (such as 20A) of the maximum power point tracking (MPPT) circuit of the photovoltaic module; the initial state of charge (SOC, such as 80%) of the battery pack and the charge - discharge rate limit of the energy storage module; the feedback power threshold (such as 5kW) of the energy feedback module. The central control module establishes connections with each module through a preset communication protocol (such as CAN bus, RS485) and loads default control strategies (such as the weight coefficients of the linear programming algorithm).

[0033] The establishment of communication connections includes the following operations: Grid power supply interface module: Connect to the central control module through the Ethernet protocol to transmit grid voltage, frequency, and power data in real - time.

[0034] Photovoltaic module: Connect to the central control module through the RS485 bus to transmit the output voltage, current, and light intensity data of the photovoltaic panel.

[0035] Energy storage module: Connect to the central control module through the CAN bus to upload the battery pack voltage, temperature, SOC, and charge - discharge status.

[0036] Energy feedback module: Connect to the central control module through the CAN bus to receive the feedback power instruction and feedback real - time feedback electrical energy data.

[0037] Central control module: Integrate the communication interface matrix unit, automatically detect the communication status of each module, and display the connection status (such as "connected" or "not connected") on the human - machine interaction interface.

[0038] It can be understood that after the communication connection is completed, the central control module can perform the following self - inspection operations: Verify whether the voltage of the grid power supply interface module is within the preset range (such as 210V - 230V).

[0039] Detect whether the maximum power point tracking circuit of the photovoltaic module is in the maximum power tracking state.

[0040] Check whether the battery management unit (BMS) of the energy storage module is working properly, including voltage balance (such as the voltage difference between battery cells ≤ 0.1V) and temperature consistency (such as temperature difference ≤ 5°C).

[0041] Verify whether the phase synchronization detection circuit of the energy feedback module is synchronized with the power grid (such as phase deviation ≤ 2°).

[0042] If the self-check passes, this application enters the ready state; if an abnormality is detected, a fault alarm is triggered and a specific error code is displayed (such as "E01: Unbalanced voltage of the energy storage module").

[0043] In a specific example, a charging pile test laboratory uses this application for testing. After the operator starts this application, the central control module automatically loads default parameters: grid voltage range 220V ± 10%, initial voltage of photovoltaic MPPT 48V, and initial value of energy storage SOC 80%. This application establishes a connection with the energy storage module through the CAN bus, detects that the SOC of the battery pack is 82%, and the voltage balance is good (maximum voltage difference 0.08V), and receives the light intensity data of the photovoltaic module through RS485 (current light intensity is 800W / m²). After the energy feedback module completes the phase synchronization detection, it displays "Grid connection ready". The human-machine interface of the central control module displays that the status of all modules is "normal", and this application enters the test preparation stage.

[0044] Step 2: Select a coordinated operation mode based on user input or preset conditions; among them, the coordinated operation modes include photovoltaic priority mode, hybrid power supply mode, and energy storage island mode.

[0045] The user selects the operation mode through the human-machine interface of the central control module: Photovoltaic priority mode: Give priority to using photovoltaic power generation to supply power to the charging pile, the energy storage module is used as a backup power source, and the grid power is only enabled when both photovoltaic and energy storage are insufficient.

[0046] Hybrid power supply mode: Dynamically allocate the power supply ratios of photovoltaic, energy storage, and the grid, give priority to using photovoltaic energy, and store the excess electric energy in the energy storage module or feed it back to the grid.

[0047] Energy storage island mode: Rely entirely on the energy storage module for independent power supply, cut off the connection with the external power grid, and is applicable to situations where the external power grid is unstable or the test scenario requires isolating grid interference.

[0048] This application supports automatic mode switching according to preset conditions, for example: When the detected light intensity continuously remains below 100 W / m² for more than 30 minutes, it automatically switches from the photovoltaic priority mode to the hybrid power supply mode.

[0049] If the grid voltage fluctuates by more than ±5V and lasts for 5 minutes, this application automatically switches to the energy storage island mode to ensure the test stability.

[0050] After selecting the mode, the central control module loads the corresponding control strategy: Photovoltaic priority mode: Set the discharge threshold of the energy storage module to SOC≥20%, and the upper limit of the grid supplementary power is 30% of the total demand.

[0051] Hybrid power supply mode: Enable the linear programming algorithm to calculate the optimal power supply ratio of photovoltaic, energy storage and grid in real time (such as 60% for photovoltaic, 30% for energy storage, and 10% for grid).

[0052] Energy storage island mode: Limit the maximum output power of the charging pile to 80% of the rated power of the energy storage module, and enable the battery health monitoring.

[0053] In a specific case, there is a test scenario to verify the performance of the charging pile under photovoltaic power supply. The operator selects the "photovoltaic priority mode" through the human-machine interface. This application automatically configures the energy storage discharge threshold to SOC≥20% and limits the grid supplementary power not to exceed 30%. At this time, the output power of the photovoltaic module is 3kW (light intensity 900 W / m²), and the power demand of the charging pile is 4kW. The central control module calls the energy storage module to supplement 1kW of power, and the grid power supply is not enabled. When the light intensity drops to 200 W / m², the photovoltaic output power drops to 0.8kW, the energy storage module supplements 3kW, and the grid power supply makes up 0.2kW. This application records the power ratio of each power supply in real time and generates optimization suggestions.

[0054] Step 3: If the photovoltaic priority mode is selected, collect the power generation data of the photovoltaic module, and give priority to calling the output power of the photovoltaic module to supply power to the charging pile. If the power generation of the photovoltaic module is insufficient, call the stored electric energy of the energy storage module to supplement the power supply. If the total power is insufficient, call the grid power supply interface module to supply power to the charging pile.

[0055] Step 3.1: Collect the ambient light data in real time through the light intensity sensor, and adjust the output voltage and current of the photovoltaic module through the maximum power point tracking circuit, so that the photovoltaic module works at the maximum power point.

[0056] For example, the light intensity sensor collects the ambient light intensity (unit: W / m²) in real time at a frequency of once per second and transmits it to the central control module through the RS485 bus.

[0057] The maximum power point tracking circuit adopts the perturbation and observation method. By finely adjusting the operating voltage of the photovoltaic module (such as adjusting from 48V to 49V), the power change is calculated in real time. If the power increases, continue to adjust in the current direction; if the power decreases, adjust in the reverse direction until the photovoltaic module stabilizes at the maximum power output point.

[0058] According to the change of light intensity (for example, from 800W / m² to 500W / m²), the maximum power point tracking circuit reduces the output current (such as adjusting from 20A to 12A) to maintain the voltage within the optimal range (such as 48V - 50V).

[0059] Step 3.2: Compare the output power of the photovoltaic module with the required power of the charging pile. If the photovoltaic output power is greater than or equal to the required power, give priority to using the photovoltaic module for power supply.

[0060] For example, the central control module collects the photovoltaic output power (such as 3kW) and the required power of the charging pile (such as 2.5kW) every 0.5 seconds. If the photovoltaic power ≥ required power, directly call the photovoltaic electric energy for power supply through the charging pile interface circuit module, and turn off the outputs of the energy storage module and the grid power interface module.

[0061] For example, when the photovoltaic output power is 3.2kW and the charging pile requirement is 3kW, this application only enables photovoltaic power supply, and the remaining 0.2kW is stored in the energy storage of this application through the energy feedback module.

[0062] Step 3.3: If the photovoltaic output power is less than the required power, call the stored electric energy of the energy storage module to supplement the power supply.

[0063] For example, when the photovoltaic power (such as 2kW) is lower than the required power (such as 3kW), the central control module sends a discharge instruction to the energy storage module.

[0064] The bi-directional energy storage converter of the energy storage module switches to the inversion mode, inverses the direct current of the battery pack (such as 48V) into alternating current (220V / 50Hz) to supplement the power supply gap (such as 1kW). At the same time, the battery management unit (BMS) monitors the battery temperature (such as ≤40℃) and SOC (such as from 80% to 75%) during the discharge process in real time.

[0065] Step 3.4: If the sum of the photovoltaic output power and the output power of the energy storage module is less than the required power, call the grid power interface module to make up the power supply.

[0066] For example, when the total power of the photovoltaic (1.5kW) and the energy storage (1kW) (2.5kW) is still lower than the required power (3kW), the central control module activates the grid power interface module and calls the remaining power (0.5kW) to make up the power supply.

[0067] The grid power supply interface module ensures that the output voltage is in the same frequency and phase as the grid through the phase synchronization detection circuit, avoiding voltage fluctuations or harmonic interference during switching.

[0068] Step 3.5: Record and upload the power supply ratio of the photovoltaic module, the power supply ratio of the energy storage module, and the power supply ratio of the external grid for supplementary power to the central control module.

[0069] For example, the data acquisition and analysis module records the power supply ratio (such as 60% for photovoltaic, 30% for energy storage, and 10% for the grid) at a frequency of once per minute and stores it in the local database.

[0070] Based on the historical ratio data, the central control module automatically optimizes the MPPT parameters (such as adjusting the perturbation step size) and the energy storage charge and discharge thresholds (such as adjusting the SOC discharge lower limit from 20% to 15%) in subsequent tests.

[0071] In a specific example, a two-wheeled electric vehicle charging pile test center selects the photovoltaic priority mode for cyclic testing. After the initialization of this application, the light intensity sensor detects that the ambient light is 750 W / m². The MPPT circuit stabilizes the output voltage of the photovoltaic module at 49 V, and the output power is 2.8 kW. The current power demand of the charging pile is 3 kW. The central control module determines that the photovoltaic power is insufficient and immediately calls the energy storage module to supplement 0.2 kW. Subsequently, the light intensity drops suddenly to 300 W / m², the photovoltaic output power drops to 1.2 kW, the energy storage module supplements 1.5 kW, and the remaining 0.3 kW is supplemented by the grid power supply. After the test, the data acquisition and analysis module generates a report showing that the photovoltaic power supply ratio is 45%, the energy storage power supply ratio is 50%, and the grid supplementary power ratio is 5%. The central control module adjusts the energy storage discharge threshold based on this data to improve the photovoltaic utilization rate in subsequent tests.

[0072] Step 4: If the hybrid power supply mode is selected, allocate the power generation power of the photovoltaic module, the discharge power of the energy storage module, and the supplementary power of the grid power supply interface module, and adjust the proportion of the power generation power, discharge power, and supplementary power based on the real-time power demand of the charging pile.

[0073] Step 4.1: Collect the power generation power of the photovoltaic module, the state of charge of the energy storage module, and the power demand of the charging pile, and calculate the optimal output ratio of the photovoltaic module, the energy storage module, and the external grid through the linear programming algorithm.

[0074] For example, the central control module obtains the output power of the photovoltaic module (such as 3.5 kW), the state of charge of the energy storage module (SOC, such as 70%), and the power demand of the charging pile (such as 4 kW) in real time at a frequency of once per second.

[0075] The linear programming algorithm uses "minimizing the grid recharge ratio" as the objective function, and the constraint conditions include the maximum output of the photovoltaic, the safe range of the energy storage SOC (such as 20% - 90%), and the upper limit of the grid power (such as 20% of the total demand).

[0076] Through solving, the distribution ratios of each power source are obtained (for example, 60% for photovoltaic, 30% for energy storage, and 10% for the grid).

[0077] Step 4.2: If the power generation of the photovoltaic module exceeds the power demand of the charging pile, determine the first excess power and store the first excess power in the energy storage module through the bi - directional energy storage converter; where the excess power is the power generation of the photovoltaic module minus the power demand of the charging pile.

[0078] For example, if the photovoltaic output power is 5kW and the charging pile demand is 4kW, then the first excess power is 1kW.

[0079] The bi - directional energy storage converter switches to the rectification mode, converts the excess power into a voltage (such as 48V) and current (such as 20A) suitable for battery charging, and simultaneously performs dynamic equalization management on the battery pack to prevent over - charging.

[0080] If the energy storage SOC is close to the preset upper limit (such as 90%), stop charging and trigger Step 4.3.

[0081] Step 4.3: If the state of charge of the energy storage module reaches the preset upper limit, determine the second excess power, and feed back the second excess power to the external grid through the energy feedback module, and record the real - time power and total amount of the feedback power.

[0082] When the energy storage SOC reaches 90% and there is still remaining power in the photovoltaic (such as photovoltaic 5kW, charging pile demand 3kW, energy storage full), then the second excess power is 2kW.

[0083] The energy feedback module converts direct current into alternating current with the same frequency and phase as the grid through a bi - directional AC / DC inverter, and realizes seamless grid connection through a phase synchronization detection circuit.

[0084] The electric energy metering unit records the feedback power in real - time (such as 2kW) and the cumulative total amount (such as the cumulative feedback of 10kWh on the same day).

[0085] Step 4.4: Adjust the output powers of the photovoltaic module, the energy storage module, and the grid power supply interface module.

[0086] According to the latest result of the linear programming algorithm, the central control module sends instructions to each module: The photovoltaic module maintains the maximum power output (such as 3.5kW).

[0087] The energy storage module discharges at a ratio of 30% (such as 1.2kW).

[0088] The grid power interface module replenishes power at a ratio of 10% (such as 0.4 kW).

[0089] If the required power of the charging pile suddenly increases (such as from 4 kW to 5 kW), this application immediately recalculates the distribution ratio and adjusts the output of each module.

[0090] Step 4.5: When abnormal voltage fluctuations of the external grid are detected, switch to the independent power supply mode of the energy storage module and trigger a grid anomaly alarm.

[0091] The grid power interface module continuously monitors the voltage fluctuation range (such as within ±5% is normal). If the detected voltage fluctuation exceeds ±10% and lasts for 1 minute, it is determined to be abnormal.

[0092] This application automatically cuts off the grid connection and switches to the independent power supply mode of the energy storage. The energy storage module provides all the required power (such as 4 kW).

[0093] The human-machine interface displays "Grid Anomaly Alarm" and records the event time, fluctuation amplitude, and switching actions.

[0094] In a specific example, a charging pile test site selects the hybrid power supply mode for long-term cyclic testing. In the initial state, the photovoltaic output power is 4 kW, the energy storage SOC is 65%, and the required power of the charging pile is 3 kW. The central control module distributes 100% (3 kW) of the photovoltaic power supply through the linear programming algorithm, and the remaining 1 kW of photovoltaic electric energy is stored in the energy storage module, and the energy storage SOC rises to 70%. Subsequently, the required power of the charging pile increases to 5 kW, and the photovoltaic output drops to 2 kW due to cloud cover. After the algorithm recalculates, it distributes 40% (2 kW) of the photovoltaic, 40% (2 kW) of the energy storage, and 20% (1 kW) of the grid.

[0095] When the energy storage SOC reaches 90% and there is still 1 kW of surplus photovoltaic power, this application feeds back the excess electric energy to the grid, and the cumulative feedback amount increases to 5 kWh. During the test, the grid suddenly has a voltage fluctuation (+12%). This application immediately switches to the independent power supply mode of the energy storage and triggers an alarm to ensure that the test is not interfered by the grid.

[0096] Step 5: If the energy storage island mode is selected, disconnect the connection of the grid power interface module and call the energy storage module to independently supply power to the charging pile.

[0097] Step 5.1: Disconnect the connection between the charging pile and the grid power interface module and call the energy storage module to independently supply power to the charging pile.

[0098] The central control module sends a disconnection command to the grid power interface module and physically cuts off the grid connection through a relay or solid-state switch to ensure that the charging pile is completely isolated from the grid.

[0099] The bi-directional power conversion system (PCS) of the energy storage module switches to the inverter mode, converting the DC power of the battery pack (such as 48V) into AC power (220V / 50Hz) to provide all the power supply for the charging pile.

[0100] The central control module monitors the output voltage and frequency in real time to ensure that they meet the input requirements of the charging pile (such as voltage error ≤ ±2%, frequency error ≤ ±0.5Hz).

[0101] Step 5.2: Monitor the state of charge of the energy storage module. If it is lower than the preset threshold, trigger an alarm and limit the maximum output power of the charging pile.

[0102] For example, the battery management unit (BMS) collects the state of charge (SOC) of the energy storage module at a frequency of once per second and uploads it to the central control module via the CAN bus.

[0103] When the SOC drops to the preset threshold (such as 20%), the central control module triggers an audible and visual alarm (such as a buzzer sounding and a red warning displayed on the interface), and limits the maximum output power of the charging pile to 80% of the current available power of the energy storage (for example, if the remaining power of the energy storage is 5kW, the power of the charging pile is limited to 4kW).

[0104] If the SOC continues to drop (such as decreasing by 5% per minute), this application gradually reduces the power limit of the charging pile (such as adjusting from 4kW to 3kW) to extend the power supply time.

[0105] Another example is that hierarchical warnings can be set: Primary warning (SOC ≤ 30%): The human-machine interface displays a yellow warning "Low energy storage capacity", maintaining the current output power but prompting the operator to prepare to switch modes.

[0106] Secondary warning (SOC ≤ 20%): Activate the power derating strategy and reduce the output power of the charging pile linearly (such as for every 1% decrease in SOC, the power upper limit decreases by 3%).

[0107] Emergency warning (SOC ≤ 10%): Forcefully turn off the high-power loads of the charging pile (such as the fast charging function), only retaining the basic communication and monitoring functions to avoid over-discharging of the battery.

[0108] During the monitoring process, the central control module synchronously collects the temperature data of the battery pack (such as ≤ 45°C). If it exceeds the limit, a temperature alarm is superimposed.

[0109] Step 5.3: Adjust the energy storage module through the equalization circuit of the battery management unit.

[0110] The equalization circuit detects the voltage difference of each cell in the battery pack (such as the maximum difference ≥ 0.1V), and transfers the energy of the high-state-of-charge cells to the low-state-of-charge cells through active equalization technology.

[0111] If the temperature of a certain battery cell exceeds the preset threshold (such as 45°C), the BMS activates the cooling air duct to force cooling and reduces the charge and discharge rate of this cell.

[0112] After balancing, the BMS recalculates the available capacity and state of health (SOH) of the battery pack and updates them to the central control module.

[0113] Step 5.4: Record the charge and discharge cycle times and capacity attenuation data of the energy storage module to generate a battery health assessment report.

[0114] The data acquisition and analysis module records the start and end times of each charge and discharge cycle, the SOC change range (such as from 80% to 20%), and the capacity attenuation value (such as the capacity drops to 95% after cycling).

[0115] Based on the capacity attenuation curve and the number of cycles, use a weighted algorithm to calculate the battery health (for example: SOH = initial capacity × (1 - 0.01 × number of cycles)).

[0116] The report includes the charge and discharge historical curves, health score, and maintenance suggestions (such as "recommended balance maintenance" or "replace aging battery cells").

[0117] In a specific case, a charging pile test station on a certain island selects the energy storage island mode due to frequent power grid failures. After this application is started, the central control module cuts off the external power grid connection, and the energy storage module provides 5 kW of power for the charging pile with an initial SOC of 80%. During the test, the SOC gradually drops to 25%, triggering a low battery warning and restricting the charging pile power to 4 kW. At the same time, the BMS detects that the voltage difference between battery cells reaches 0.15 V, and the balancing circuit is activated to transfer the excess energy of cell No. 3 to cell No. 1, restoring the voltage difference to within 0.05 V. After the test, this application records a 0.5% capacity attenuation for this cycle and generates a report showing a battery health of 94%, recommending a deep balance maintenance every 50 cycles.

[0118] Step 6: Monitor the electrical energy consumed by the multi-modal test load module through the energy feedback module, convert the consumed electrical energy into feedback electrical energy, and select to feedback it to the external power grid or the energy storage module according to the state of charge of the energy storage module.

[0119] Step 6.1: Electrical energy consumption monitoring and feedback determination.

[0120] The energy feedback module collects the input power (such as voltage, current, and power values) of the multi-modal test load module in real time and transmits it to the central control module through the CAN bus.

[0121] The central control module determines that the feedable electric energy is 1 kWh based on the difference between the total electric energy consumed by the load (such as 5 kWh) and the electric energy output by the charging pile (such as the charging pile outputs 6 kWh and the load consumes 5 kWh).

[0122] If the state of charge (SOC) of the energy storage module is lower than the preset feed-back threshold (such as 80%), the feedable electric energy is preferentially stored in the energy storage module; if the SOC is higher than the threshold, the electric energy is fed back to the power grid.

[0123] Step 6.2, Electric energy conversion and feed-back control The bidirectional DC / DC converter of the energy feed-back module boosts the direct current consumed by the load to the charging voltage of the energy storage of this application (such as 48 V) and stores it in the battery pack through the bidirectional energy storage converter.

[0124] The bidirectional AC / DC inverter converts the direct current into alternating current (220 V / 50 Hz) with the same frequency and phase as the power grid and realizes seamless grid connection through the phase synchronization detection circuit.

[0125] If the energy storage SOC reaches the threshold, this application still preferentially feeds back the electric energy to the power grid to avoid overcharging.

[0126] Step 6.3, Safety verification during the feed-back process The energy feed-back module continuously detects the power grid voltage fluctuation range (such as ±5%). If it exceeds the allowable range, the feed-back is suspended and an abnormal alarm is triggered.

[0127] The battery management unit monitors the battery temperature (such as ≤45°C) and voltage balance (such as the monomer voltage difference ≤0.1 V) during the feed-back charging process. If it is abnormal, the feed-back is terminated.

[0128] In a specific example, a certain test center conducts a full-load test of the charging pile. The multi-modal test load consumes 4 kWh of electric energy, the charging pile outputs 5 kWh of electric energy, and 1 kWh of feedable electric energy is generated. At this time, the SOC of the energy storage module is 75%, which is lower than the feed-back threshold of 80%. This application stores 1 kWh of electric energy in the energy storage module through the bidirectional DC / DC converter, and the SOC rises to 78%.

[0129] During the test the next day, the energy storage SOC has reached 88%. Under the same conditions, this application feeds back the electric energy to the external power grid.

[0130] Step 7, Record the output parameters of the charging pile, the input parameters of the test load and the energy feed-back efficiency data through the data acquisition and analysis module, and generate a performance evaluation report including voltage fluctuation rate, current stability and comprehensive energy efficiency ratio.

[0131] Step 7.1, Multi-dimensional data acquisition.

[0132] Output parameters of the charging pile: including output voltage (such as 220V±2%), output current (such as 10A±5%), real-time power and efficiency (such as conversion efficiency≥95%).

[0133] Input parameters of the test load: Record the voltage fluctuation rate of the load (such as ±1.5%), current harmonic distortion rate (such as ≤3%) and dynamic load response time (such as ≤100ms).

[0134] Energy feedback efficiency: Calculate the proportion of electric energy fed back to the power grid or energy storage (such as feedback efficiency≥90%) and loss analysis (such as the proportion of inverter loss is 5%).

[0135] Step 7.2, Data analysis and report generation For example, based on the data sampled per second, statistically analyze the maximum amplitude of the voltage deviation from the rated value during the test period (such as ±2%).

[0136] Analyze the current fluctuation range (such as ±0.5A) through standard deviation analysis and combine with the transient response data when the load is switched.

[0137] Integrate the charging pile efficiency, feedback efficiency and energy storage cycle efficiency (such as the overall energy efficiency ratio of this application≥85%).

[0138] Automated report generation: The data acquisition and analysis module integrates the above parameters into a structured report, including line charts (such as voltage change curve over time), bar charts (such as the proportion of each energy source) and text conclusions.

[0139] In a specific case, the laboratory conducted a 72-hour cyclic test on the charging pile. The data acquisition module recorded that the output voltage fluctuation rate was ±1.8%, the standard deviation of current stability was 0.3A, and the energy feedback efficiency was 92%. The report pointed out that the instantaneous voltage dropped by 2.5% during dynamic load switching, and it was recommended to optimize the response algorithm of the energy feedback module. The report compared the energy efficiency ratios in different modes through charts and showed that the overall energy efficiency ratio of the hybrid power supply mode was the highest (88%).

[0140] Step 8, Based on the performance evaluation report, optimize the energy distribution strategy through the central control module, and adjust the maximum power point tracking parameters of the photovoltaic module, the charge and discharge rate of the energy storage module and the switching logic of the energy feedback module.

[0141] Step 8.1, Basis for strategy optimization If the report shows that the photovoltaic utilization rate is lower than expected (such as 80%), then reduce the perturbation step of the maximum power point tracking circuit (such as from 1V to 0.5V) to improve the tracking accuracy when the light intensity fluctuates.

[0142] Adjust the upper limit of charge and discharge current according to the State of Health (SOH) data of the battery (for example, when SOH ≥ 90%, the maximum allowable current is 20A; when SOH < 90%, it is limited to 15A).

[0143] If the grid feedback failure rate is relatively high (such as > 5%), then extend the phase synchronization detection time (such as from 100ms to 200ms), and increase the voltage fluctuation tolerance range (such as ±7%).

[0144] Step 8.2, Implementation of closed-loop control Automatic parameter update: The central control module directly writes the optimized parameters (such as MPPT step size, charge and discharge rate) into the controllers of each sub-module without manual intervention.

[0145] Historical data learning: Based on multiple test reports, this application establishes a database and predicts the optimal parameter combination through machine learning algorithms (such as preferentially reducing the energy storage discharge rate in overcast scenarios).

[0146] Step 8.3, Verification and re-optimization Simulation test: After adjusting the parameters, this application verifies the effectiveness of the strategy by simulating different lighting, load, and grid conditions (such as simulating the MPPT response when the light intensity suddenly increases from 200W / m² to 800W / m²).

[0147] Iterative upgrade mechanism: If the new strategy leads to a decrease in the energy efficiency ratio (such as from 85% to 82%), this application automatically rolls back to the parameters of the previous version and records the reason for the anomaly.

[0148] In a specific case, a charging pile manufacturer found that the photovoltaic utilization rate was only 78% according to the test report. The central control module automatically adjusted the MPPT perturbation step size from 1V to 0.5V. After optimization, the photovoltaic utilization rate increased to 85% in the scenario of rapid light change. At the same time, for the problem that the SOH of a certain batch of batteries dropped to 88%, this application reduced the upper limit of the charge and discharge current from 20A to 18A, and the peak battery temperature decreased by 5°C to extend the battery life.

Claims

1. A charging pile test system based on energy feedback and photovoltaic energy storage, applied to the test of charging piles, wherein the charging piles are used to charge two-wheeled electric vehicles, characterized in that: The system comprises: A power grid interface module, used to connect to an external power grid and receive power from the external power grid; Photovoltaic module modules, which are used to convert solar energy into direct current electricity and optimize the output power; An energy storage module, comprising a lithium iron phosphate battery pack, a bidirectional energy storage converter, a battery management unit and a DC bus, wherein the bidirectional energy storage converter is connected to the DC bus for storing and releasing electric energy; A charging pile interface circuit module, used to access the charging pile and interact with the charging pile; Multi-mode test load module, used to simulate load characteristics under different charging conditions; An energy feedback module, used for converting the electric energy of the multimodal test load module into recyclable electric energy and feeding it back to the external power grid or energy storage module; A central control module, connected to the photovoltaic module module, the energy storage module, the energy feedback module and the charging pile interface circuit module, for collecting data and generating energy distribution control instructions; The data acquisition and analysis module is used to record the output parameters of the charging pile, the input parameters of the multi-modal test load module and the energy feedback efficiency, and generate a performance evaluation report.

2. A charging pile test system based on energy feedback and photovoltaic energy storage according to claim 1, characterized in that: The photovoltaic assembly module comprises: A monocrystalline photovoltaic panel array, comprising a plurality of monocrystalline photovoltaic panels, for absorbing solar energy; A maximum power point tracking circuit, which adjusts the operating voltage and current of the monocrystalline photovoltaic panel array based on a preset perturbation observation method; A light intensity sensor monitors ambient light data in real time and transmits the data to the central control module; Anti-reverse diode, used to prevent current from flowing backwards; Fuse, for overload protection; The DC combiner box is used to combine the outputs of multiple photovoltaic panels and then connect them to the DC bus of the energy storage module.

3. A charging pile test system based on energy feedback and photovoltaic energy storage according to claim 1, characterized in that: The energy storage module comprises: A lithium iron phosphate battery pack, comprising a plurality of lithium iron phosphate batteries, for storing electrical energy; A bidirectional energy storage converter, used to switch the charging and discharging state according to the instructions of the central control unit; A battery management unit, including a voltage collector, a temperature sensor, and a balancing circuit, is used to monitor the status of multiple lithium iron phosphate batteries and make adjustments; A heat dissipation duct and a temperature control device, used to adjust the heat dissipation intensity according to the temperature of the lithium iron phosphate battery pack; The energy storage status display screen is used to display the charge state, health and charge and discharge power of the lithium iron phosphate battery pack.

4. A charging pile test system based on energy feedback and photovoltaic energy storage according to claim 1, characterized in that: The energy feedback module comprises: A bidirectional DC / DC converter, used to boost the low-voltage direct current output from the interface of the charging pile to high-voltage direct current; A bidirectional AC / DC inverter, connected to the grid power interface module, for converting strong high-voltage direct current into alternating current with the same frequency and phase as the external grid; A phase synchronization detection circuit, used for monitoring the voltage and frequency of the external power grid, so as to adjust the inverter output phase and connect to the external power grid; Energy feedback switch, used to select the energy feedback to the grid or energy storage module according to the charge state of the energy storage module; The electric energy metering unit is used to record the power and accumulated total amount of the feedback electric energy.

5. A charging pile test system based on energy feedback and photovoltaic energy storage according to claim 1, characterized in that: The multi-modal test load module includes: Adjustable constant resistance load, used to adjust the resistance value to simulate a static load; Dynamic electronic load controller, which generates dynamic load waveform based on preset riding condition curve to simulate actual charging power fluctuation; Battery simulators, used to simulate the charging response characteristics of different battery types; Load parameter acquisition unit, used to capture voltage, current and power data and transmit them to the data acquisition and analysis module; A multiplexer switch is used to switch the combination mode of the adjustable constant resistance load, the dynamic electronic load controller and the battery simulator.

6. A charging pile test system based on energy feedback and photovoltaic energy storage according to claim 1, characterized in that: The central control module comprises: A communication interface matrix unit, used to connect with the photovoltaic component module, energy storage module, energy feedback module and charging pile interface circuit module, and perform data interaction; A data processing unit, used to calculate the power generation of the photovoltaic module, the state of charge of the energy storage module and the required power of the charging pile; A control strategy generation unit, used to allocate the power supply ratio of the photovoltaic component module, the energy storage module and the external power grid based on a preset linear programming algorithm; Fault diagnosis unit, used to detect abnormal status of photovoltaic module, energy storage module, energy feedback module and charging pile interface circuit module and trigger protection mechanism; The human-computer interaction interface is used to provide working mode selection, parameter setting and operation status display functions.

7. A charging pile testing method based on energy feedback and photovoltaic energy storage, applied to a charging pile testing system based on energy feedback and photovoltaic energy storage as claimed in claims 1-6, characterized in that: The method comprises: Initialize operating parameters and establish communication connections between the grid power interface module, photovoltaic module module, energy storage module, energy feedback module and central control module; Selecting a coordinated operation mode based on user input or preset conditions; wherein the coordinated operation mode includes a photovoltaic priority mode, a hybrid power supply mode, and an energy storage island mode; If the photovoltaic priority mode is selected, the power generation data of the photovoltaic module is collected, and the output power of the photovoltaic module is preferentially called to power the charging pile. If the power generation power of the photovoltaic module is insufficient, the stored electric energy of the energy storage module is called to supplement the power supply. If the total power is insufficient, the grid power interface module is called to power the charging pile. If the hybrid power supply mode is selected, the power generation power of the photovoltaic module, the discharge power of the energy storage module and the supplementary power of the grid power interface module are allocated, and the proportion of the power generation power, discharge power and supplementary power is adjusted based on the real-time power demand of the charging pile; If the energy storage island mode is selected, the connection of the grid power interface module is cut off, and the energy storage module is called to independently power the charging pile; The energy feedback module monitors the electric energy consumed by the multi-modal test load module, converts the consumed electric energy into recyclable electric energy, and selectively feeds back the electric energy to the external power grid or the energy storage module according to the charge state of the energy storage module; The data acquisition and analysis module records the output parameters of the charging pile, the input parameters of the test load and the energy feedback efficiency data, and generates a performance evaluation report including voltage fluctuation rate, current stability and comprehensive energy efficiency ratio; Based on the performance evaluation report, the energy allocation strategy is optimized through the central control module, and the maximum power point tracking parameters of the photovoltaic module module, the charge and discharge rate of the energy storage module and the switching logic of the energy feedback module are adjusted.

8. A charging pile testing method based on energy feedback and photovoltaic energy storage according to claim 7, characterized in that: If the photovoltaic priority mode is selected, the power generation data of the photovoltaic module is collected, and the output power of the photovoltaic module is preferentially called to power the charging pile. If the power generation power of the photovoltaic module is insufficient, the stored electric energy of the energy storage module is called to supplement the power supply. If the total power is insufficient, the grid power interface module is called to power the charging pile, which specifically includes: The light intensity sensor is used to collect ambient light data in real time, and the maximum power point tracking circuit is used to adjust the output voltage and current of the photovoltaic module so that the photovoltaic module operates at the maximum power point; Compare the output power of the PV module with the required power of the charging pile. If the PV output power is greater than or equal to the required power, the PV module will be used for power supply first. If the photovoltaic output power is less than the required power, the stored energy of the energy storage module is used to supplement the power supply; If the sum of the photovoltaic output power and the output power of the energy storage module is less than the required power, the grid power interface module is called to supplement the power supply; The power supply proportion of the photovoltaic component module, the power supply proportion of the energy storage module and the power supplement proportion of the external power grid are recorded and uploaded to the central control module.

9. A charging pile testing method based on energy feedback and photovoltaic energy storage according to claim 7, characterized in that: If the hybrid power supply mode is selected, the power generation power of the photovoltaic module, the discharge power of the energy storage module and the supplementary power of the grid power interface module are allocated, and the proportion of the power generation power, discharge power and supplementary power is adjusted based on the real-time power demand of the charging pile, specifically including: Collect the power generation of the photovoltaic module, the state of charge of the energy storage module and the power demand of the charging pile, and calculate the optimal output ratio of the photovoltaic module, the energy storage module and the external power grid through the linear programming algorithm; If the power generation of the photovoltaic component module exceeds the power demand of the charging pile, the first excess electric energy is determined, and the first excess electric energy is stored in the energy storage module through the bidirectional energy storage converter; wherein the excess electric energy is the power generation of the photovoltaic component module minus the power demand of the charging pile; If the state of charge of the energy storage module reaches a preset upper limit, the second excess electric energy is determined, and the second excess electric energy is fed back to the external power grid through the energy feedback module, and the real-time power and total amount of the fed-back electric energy are recorded; Adjust the output power of photovoltaic module, energy storage module and grid power interface module; When an abnormal grid voltage fluctuation of the external grid is detected, the system switches to the independent power supply mode of the energy storage module and triggers a grid abnormality alarm.

10. A charging pile testing method based on energy feedback and photovoltaic energy storage according to claim 7, characterized in that: If the energy storage island mode is selected, the connection of the grid power interface module is cut off, and the energy storage module is called to independently power the charging pile, including: Cut off the connection between the charging pile and the grid power interface module, and call the energy storage module to independently power the charging pile; Monitor the state of charge of the energy storage module. If it is lower than the preset threshold, an alarm is triggered and the maximum output power of the charging pile is limited; The energy storage module is adjusted through the balancing circuit of the battery management unit; Record the number of charge and discharge cycles and capacity attenuation data of the energy storage module to generate a battery health assessment report.

Images