Portable power supply box based on comprehensive energy cooperative control

Abstract

The invention relates to a portable power supply box based on comprehensive energy cooperative control, and the box comprises a power supply box body which comprises a photovoltaic power generation module, a storage battery energy storage module, an inverter module, an AC input port, a DC output port, an AC output port, and a power management module. The photovoltaic power generation module is used for obtaining direct-current electric energy and outputting the direct-current electric energy to the storage battery energy storage module for storage; the storage battery energy storage module outputs direct-current electric energy to the direct-current output port or the inverter module; the DC output port supplies power to a DC load. The inverter module converts direct current into alternating current, and the alternating current and electric energy input by the alternating current input port are jointly output to the alternating current output port to supply power to an alternating current load. And the power management module adopts an OpenHarmony-based embedded architecture and is used for carrying out short-time output prediction based on photovoltaic output and carrying out energy storage dynamic adjustment by considering photovoltaic output and load response.

Description

Technical Field

[0001] The invention relates to a portable power supply box based on comprehensive energy coordinated control, belonging to the technical field of power supply boxes. Background Art

[0002] Since the outdoor operation location of the substation is relatively flexible, but the number of fixed power supply points is limited, the actual work of obtaining power is relatively cumbersome, so power supply boxes are usually carried for outdoor work to obtain power. At the same time, the size of the power supply box limits the power size of the power module and the energy storage capacity carried. Therefore, the existing power supply box is large in size and is not easy to carry. The energy storage in the portable power supply box is difficult to support outdoor work with a large workload.

[0003] In order to solve the problem of temporary power supply for various outdoor operations, the size of the power supply box and the size of the energy storage capacity can be taken into consideration. The photovoltaic power generation module and the battery energy storage module can be combined to optimize the box space structure and design a multi-port split circuit topology on the basis of ensuring the power supply performance such as battery life and output power. However, due to the continuous changes of solar energy with day and night, seasons, and meteorological factors, photovoltaic power generation is intermittent and uncertain, and the output power stability of photovoltaic modules is poor, which is inconsistent with the reliability requirements of outdoor operation electricity. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention proposes a portable power supply box based on comprehensive energy coordinated control.

[0005] The technical solution of the present invention is as follows:

[0006] A portable power supply box based on comprehensive energy coordinated control includes a power supply box body, which includes:

[0007] Photovoltaic power generation module, battery energy storage module, inverter module, AC input port, DC output port, AC output port and power management module;

[0008] The photovoltaic power generation module is used to obtain DC power and output it to the battery energy storage module for storage; the battery energy storage module outputs DC power to the DC output port or the inverter module; the DC output port supplies power to the DC load; the inverter module converts the DC power into AC power and outputs it together with the power input from the AC input port to the AC output port to supply power to the AC load;

[0009] The power management module adopts an embedded architecture based on OpenHarmony, which is used to perform short-term output prediction based on photovoltaic output, and to dynamically adjust energy storage taking into account photovoltaic output and load response.

[0010] As a preferred embodiment, the photovoltaic power generation module comprises:

[0011] PV solar panels and MPPT units;

[0012] The MPPT unit adopts Boost topology as the main circuit and tracks the maximum output power operating point under the light intensity and temperature of the PV solar panel through the perturbation observation method.

[0013] As a preferred embodiment, the battery energy storage module comprises:

[0014] Lithium battery and bidirectional DC-DC converter unit;

[0015] The bidirectional DC-DC converter unit operates in Boost mode during the discharge phase and in Buck mode during the charge phase according to the instruction sent by the power management module, and does not operate and disconnects the switch during the static phase.

[0016] As a preferred implementation, the inverter module includes:

[0017] DC bus unit, inverter unit and EMC filter unit;

[0018] The DC bus unit converges the electric energy generated by the photovoltaic power generation module and the battery energy storage module, and uses multiple electrolytic capacitors in parallel to maintain the stability of the inverter input voltage;

[0019] The inverter unit adopts a single-phase full-bridge inverter topology as a main circuit to realize DC-AC conversion of electric energy, and the output current of the inverter module is obtained after filtering by the EMC filter unit.

[0020] As a preferred implementation, the power management module is embeddedly developed using an MCU controller adapted to OpenHarmony, which is used to perform A / D conversion and calculation processing on the collected voltage and current analog data, and issue instructions to the battery energy storage module and inverter module to perform dynamic energy storage adjustment.

[0021] As a preferred implementation, the MCU controller collects the voltage, current and frequency output by the photovoltaic power generation module, the battery energy storage module and the inverter module, and controls the charging and discharging behavior of the battery energy storage module in combination with the short-term output prediction curve of the photovoltaic power generation module, the battery safety protection and the load size, and optimizes the peak and frequency regulation performance.

[0022] As a preferred implementation, the step of predicting short-term output based on photovoltaic output is specifically as follows:

[0023] The MCU controller collects the output voltage and output current of the photovoltaic power generation module, calculates the current output power, combines the current ambient temperature, air pressure, and humidity data, and inputs them into the pre-trained photovoltaic short-term output prediction model based on the neural network algorithm;

[0024] The output power prediction value of the photovoltaic power generation module is output through the photovoltaic short-term output prediction model.

[0025] As a preferred embodiment, the step of controlling the charging and discharging behavior of the battery energy storage module includes:

[0026] The MCU controller collects the voltage and current data of the battery energy storage module and calculates the remaining charge capacity of the battery;

[0027] The remaining charge capacity is estimated by the ampere-hour integration method during the battery charging and discharging stage, and the remaining charge capacity is estimated by the open circuit voltage method during the battery static stage;

[0028] If the calculated remaining charge capacity value is higher than the set safety upper limit, the charging behavior is stopped; if it is lower than the set safety lower limit, the discharging behavior is stopped.

[0029] Additional aspects and advantages of the present invention will be set forth in the following description, and some of them will be apparent from the description, or may be understood by practicing the present invention. In addition, the various aspects and advantages of the present invention may be realized and obtained by the method steps and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the module structure of an embodiment of the present invention;

[0031] Figure 2 A flowchart of short-term output prediction in an embodiment of the present invention;

[0032] Figure 3 Schematic diagram of the working process of the power supply box in the embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0035] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0036] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0037] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0038] See also Figure 1 This embodiment provides a portable power supply box based on comprehensive energy coordinated control to meet the requirements of portability and excellent power supply performance for outdoor operation. The portable power supply box includes a power supply box body, which includes:

[0039] Hardware platform and software platform, the hardware platform includes photovoltaic power generation module, battery energy storage module, inverter module, AC input port, DC output port and AC output port, and the software platform includes power management module;

[0040] The photovoltaic power generation module is used to obtain DC power and output it to the battery energy storage module for storage; the battery energy storage module outputs DC power to the DC output port or the inverter module; the DC output port supplies power to the DC load; the inverter module converts the DC power into AC power and outputs it together with the power input from the AC input port to the AC output port to supply power to the AC load;

[0041] The power management module adopts an embedded architecture based on OpenHarmony, which is used to perform short-term output prediction based on photovoltaic output, and to dynamically adjust energy storage taking into account photovoltaic output and load response.

[0042] This embodiment is compatible with AC power and photovoltaic input, and realizes three major functions: energy storage, DC output (USB interface supporting multiple fast charging protocols) and AC output (220V / 50Hz sinusoidal AC), and intelligent power management. Among them, a high-energy-density lithium battery is used as a storage battery, which can be charged by photovoltaic power generation or AC power to reduce the size of the power supply box and improve the sustainability of power supply. The power management module predicts the short-term photovoltaic output, and coordinates the energy flow of each module based on the prediction results, input and output power, and battery SOC to meet the requirements of excellent power supply performance, and feeds back data such as switching mode, voltage, current, power and battery capacity to the user interface to achieve an intuitive user experience.

[0043] In this embodiment, the power management module is based on the open source Hongmeng (OpenHarmony) architecture, and is divided into three layers as a whole, namely the physical layer, the application layer and the interface interaction layer. Among them, the physical layer directly faces the underlying hardware of the hardware platform, and its main function is to configure and initialize the on-chip peripherals. At the same time, it accepts the call of the application layer program, connects to the interface of the hardware platform downward, and realizes the management and control of the hardware platform through the hardware abstraction layer interface of OpenHarmony, which mainly includes hardware initialization program, interrupt handler, system clock configuration program, etc.; the application layer, as an intermediate layer, mainly functions for information detection, processing and communication, accepts the call of the interface interaction layer upward, and calls the program of the physical layer downward, including communication configuration, signal acquisition, data packet analysis, fault detection system, screen status display and other modules. Among them, the signal acquisition module will sample the analog signal and perform A / D conversion to obtain a digital signal; the screen status display module relies on the corresponding screen driver; the fault detection system is responsible for fault diagnosis of each module with the help of the real-time operating system of the open source Hongmeng; the upper layer is the interface interaction layer, which interacts with the user and calls the application layer program downward. Its main functions include status display, data feedback and some embedded algorithms. The status display is used to visualize the real-time changes in switch mode, voltage, current, power and battery capacity. Through OpenHarmony's UI components, various data are fed back to the user operation interface to achieve a more intuitive user interaction experience.

[0044] Since the photovoltaic panel is affected by external factors such as light intensity and environment, its output power varies. In one embodiment, the photovoltaic power generation module includes:

[0045] PV solar panels and MPPT units;

[0046] The MPPT unit adopts Boost topology as the main circuit and tracks the maximum output power operating point of the PV solar panel under the light intensity and temperature through the perturbation observation method. PV , output current i PV Calculate the instantaneous power P PV , and according to P PV and u PV The maximum power point tracking (MPPT) is realized by changing the direction of the power supply, so that the PV solar panel can output the maximum power under the current environment.

[0047] In one embodiment, the battery energy storage module comprises:

[0048] Lithium battery and bidirectional DC-DC converter unit;

[0049] The bidirectional DC-DC converter unit operates in Boost mode during the discharge phase and in Buck mode during the charge phase according to the instruction sent by the power management module, and does not operate and disconnects the switch during the static phase.

[0050] As a preferred implementation, the inverter module includes:

[0051] DC bus unit, inverter unit and EMC filter unit;

[0052] The DC bus unit converges the electric energy generated by the photovoltaic power generation module and the battery energy storage module, and uses multiple electrolytic capacitors in parallel to maintain the stability of the inverter input voltage;

[0053] The inverter unit adopts a single-phase full-bridge inverter topology as a main circuit to realize DC-AC conversion of electric energy, and the output current of the inverter module is obtained after filtering by the EMC filter unit.

[0054] As a preferred implementation, the power management module is embeddedly developed using an MCU controller adapted to OpenHarmony, which is used to perform A / D conversion and calculation processing on the collected voltage and current analog data, and issue instructions to the battery energy storage module and inverter module to perform dynamic energy storage adjustment.

[0055] As a preferred implementation, the MCU controller collects the voltage, current and frequency output by the photovoltaic power generation module, the battery energy storage module and the inverter module, and controls the charging and discharging behavior of the battery energy storage module in combination with the short-term output prediction curve of the photovoltaic power generation module, the battery safety protection and the load size, and optimizes the peak and frequency regulation performance.

[0056] As a preferred implementation, the step of predicting short-term output based on photovoltaic output is specifically as follows:

[0057] The MCU controller collects the output voltage and output current of the photovoltaic power generation module, calculates the current output power, combines the current ambient temperature, air pressure, and humidity data, and inputs them into the pre-trained photovoltaic short-term output prediction model based on the neural network algorithm;

[0058] In this embodiment, a photovoltaic short-term output prediction model is established based on a gated recurrent unit (GRU), and the GRU modeling hyperparameters are optimized by the Grey Wolf Algorithm (GWO). When the GRU network meets the training end conditions, the GRU model is obtained, and the photovoltaic output power prediction value P of the next sampling period can be calculated. pre .

[0059] Specifically, see Figure 2, the training of the photovoltaic short-term output prediction model first needs to normalize the variable data (including ambient temperature, air pressure, humidity, photovoltaic output power in the previous sampling period, photovoltaic output power in the current sampling period), and try to avoid the algorithm running into local optimality due to excessively large or small values, and divide it into test set and training set. The normalization process is shown in the following formula:

[0060]

[0061] In the formula, x n is the standard data after normalization; x is the original data before normalization; x max 、x min are the maximum and minimum values ​​in the original data.

[0062] After that, the initial value of GRU model training is set, and the GRU neural network model is established according to the input variables and output variables. Then, the GWO algorithm is used to optimize the four parameters of the number of hidden layer neurons, learning rate, and maximum number of training times. The optimization is continuously iterated until the optimization end condition is met, and finally the GWO-GRU prediction model is obtained to predict the short-term output of photovoltaic power. The optimization end condition is selected to calculate the root mean square error (RMSE) between the predicted value and the true value. RMSE As the evaluation criteria,

[0063]

[0064] Among them, y i is the actual value of the photovoltaic power generation module output power, is the predicted value of the photovoltaic power generation module output power, and n is the number of samples.

[0065] The output power prediction value of the photovoltaic power generation module is output through the trained photovoltaic short-term output prediction model.

[0066] In one embodiment, the step of controlling the charging and discharging behavior of the battery energy storage module includes:

[0067] The MCU controller collects the voltage and current data of the battery energy storage module and calculates the remaining charge capacity of the battery;

[0068] The remaining charge capacity is estimated by the ampere-hour integration method during the battery charging and discharging stage, and the remaining charge capacity is estimated by the open circuit voltage method during the battery static stage;

[0069] If the calculated remaining charge capacity value is higher than the set safety upper limit, the charging behavior is stopped; if it is lower than the set safety lower limit, the discharging behavior is stopped.

[0070] This embodiment calculates the SOC (remaining charge capacity) by the ampere-hour integration method and the open circuit voltage method to ensure that the lithium battery is in a safe operating range, and reflects the SOC value to the user interface (UI) of the power supply box so that the operator knows the remaining battery power.

[0071] By calculating the voltage and current of the AC output port and the AC input port, the power P of the output port is calculated. o and the input port power P i , frequency f i , combined with P pre If the SOC is lower than the safety lower limit, the discharge is stopped; if the SOC is higher than the safety upper limit, the charging is stopped. This instruction has the highest priority to ensure the safe operation of the lithium battery. pre +P i <P o or i <49.5Hz, the battery releases energy and generates active power. On the contrary, if P pre +P i >P o or i >50.5Hz, energy is stored to optimize peak and frequency modulation performance.

[0072] See also Figure 3 , based on the above embodiment, when the power supply box starts to run, the power management module first checks whether the inverter module and the photovoltaic power generation module are operating normally. If the inverter module is not operating, the battery is only charged but not discharged. If the photovoltaic power generation module is not operating, the battery can only be charged by the mains. If the inverter module and the photovoltaic power generation module are both operating normally, the MCU calculates the sampled data. First, it should ensure that the photovoltaic power generation module operates at the maximum power in the current environment, that is, through the perturbation observation method, the open circuit voltage fluctuates around the highest power voltage point, so as to make it emit the maximum power. Then, a photovoltaic short-term output prediction model is established according to GRU, and the four parameters of the number of hidden layer neurons, learning rate, and maximum number of training times are iteratively optimized using the GWO algorithm to make the training parameters of the prediction model better, so as to ensure the accuracy of the prediction and minimize the time consumption of model establishment and model operation, and improve the comprehensive effect of photovoltaic power generation prediction. After completing the photovoltaic short-term output prediction, combined with the prediction result P pre , battery SOC, input power P i , output power P o , coordinate the energy flow of each module, if P pre +P i <P o, it means that the energy of the photovoltaic module and the AC input port is not enough to support the load. At this time, if the battery SOC is in the safe range, the Buck-Boost circuit in the battery energy storage module works in the Boost mode, boosts the battery voltage, and sends AC power through the inverter module, and outputs AC power to the load through the inverter circuit. Conversely, if P pre +P i >P o , indicating that the energy from the photovoltaic module and the AC input port alone is sufficient to support the load. At this time, if the battery SOC is in the safe range, the Buck-Boost circuit works in Buck mode, reducing the voltage on the DC bus and storing the excess energy in the battery.

[0073] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, c can be single or multiple.

[0074] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0075] In several embodiments provided in the present application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory; hereinafter referred to as: ROM), random access memory (Random Access Memory; hereinafter referred to as: RAM), disk or optical disk, and other media that can store program codes.

[0076] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A portable power supply box based on comprehensive energy coordinated control, comprising a power supply box body, characterized in that: The power supply box body includes: Photovoltaic power generation module, battery energy storage module, inverter module, AC input port, DC output port, AC output port and power management module; The photovoltaic power generation module is used to obtain DC power and output it to the battery energy storage module for storage; the battery energy storage module outputs DC power to the DC output port or the inverter module; the DC output port supplies power to the DC load; the inverter module converts the DC power into AC power and outputs it together with the power input from the AC input port to the AC output port to supply power to the AC load; The power management module adopts an embedded architecture based on OpenHarmony, which is used to perform short-term output prediction based on photovoltaic output, and to dynamically adjust energy storage taking into account photovoltaic output and load response.

2. According to claim 1, a portable power supply box based on comprehensive energy coordinated control is characterized in that: The photovoltaic power generation module comprises: PV solar panels and MPPT units; The MPPT unit adopts Boost topology as the main circuit and tracks the maximum output power operating point under the light intensity and temperature of the PV solar panel through the perturbation observation method.

3. According to the portable power supply box based on comprehensive energy coordinated control according to claim 1, it is characterized in that: The battery energy storage module comprises: Lithium battery and bidirectional DC-DC converter unit; The bidirectional DC-DC converter unit operates in Boost mode during the discharge phase and in Buck mode during the charge phase according to the instruction sent by the power management module, and does not operate and disconnects the switch during the static phase.

4. According to the portable power supply box based on comprehensive energy coordinated control according to claim 1, it is characterized in that: The inverter module comprises: DC bus unit, inverter unit and EMC filter unit; The DC bus unit converges the electric energy generated by the photovoltaic power generation module and the battery energy storage module, and uses multiple electrolytic capacitors in parallel to maintain the stability of the inverter input voltage; The inverter unit adopts a single-phase full-bridge inverter topology as a main circuit to realize DC-AC conversion of electric energy, and the output current of the inverter module is obtained after filtering by the EMC filter unit.

5. According to claim 1, a portable power supply box based on comprehensive energy coordinated control is characterized in that: The power management module is developed using an MCU controller adapted to OpenHarmony for embedded development, which is used to perform A / D conversion and calculation processing on the collected voltage and current analog data, and to issue instructions to the battery energy storage module and inverter module to perform dynamic energy storage adjustment.

6. A portable power supply box based on comprehensive energy coordinated control according to claim 5, characterized in that: The MCU controller collects the voltage, current and frequency output by the photovoltaic power generation module, battery energy storage module and inverter module, and controls the charging and discharging behavior of the battery energy storage module in combination with the short-term output prediction curve of the photovoltaic power generation module, battery safety protection and load size, and optimizes the peak and frequency regulation performance.

7. The portable power supply box based on comprehensive energy coordinated control according to claim 5 is characterized in that: The steps of predicting short-term output based on photovoltaic output are specifically as follows: The MCU controller collects the output voltage and output current of the photovoltaic power generation module, calculates the current output power, combines the current ambient temperature, air pressure, and humidity data, and inputs them into the pre-trained photovoltaic short-term output prediction model based on the neural network algorithm; The output power prediction value of the photovoltaic power generation module is output through the photovoltaic short-term output prediction model.

8. The portable power supply box based on comprehensive energy coordinated control according to claim 5 is characterized in that: The step of controlling the charging and discharging behavior of the battery energy storage module includes: The MCU controller collects the voltage and current data of the battery energy storage module and calculates the remaining charge capacity of the battery; The remaining charge capacity is estimated by the ampere-hour integration method during the battery charging and discharging stage, and the remaining charge capacity is estimated by the open circuit voltage method during the battery static stage; If the calculated remaining charge capacity value is higher than the set safety upper limit, the charging behavior is stopped; if it is lower than the set safety lower limit, the discharging behavior is stopped.

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