Outdoor solar fast charging device based on double-shaft sun tracking and working method
By employing a dual-axis solar tracking system and intelligent control strategies, the problems of low energy capture efficiency, easily damaged structure, and power consumption mismatch in outdoor charging devices have been solved, achieving efficient and reliable fast charging and low power consumption, adapting to changing environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- STATE GRID SHANXI ELECTRIC POWER COMPANY CHANGZHIELECTRIC POWER SUPPLY
- Filing Date
- 2026-02-04
- Publication Date
- 2026-05-05
AI Technical Summary
Existing outdoor solar charging devices suffer from problems such as low energy capture efficiency, easily damaged structure, mismatch between power consumption and efficiency, poor environmental adaptability, and conflict between portability and functionality.
It adopts a dual-axis solar tracking system, combining a four-quadrant photosensitive sensor and an inertial measurement unit, and achieves high-precision tracking through closed-loop control. It combines light intensity sensing and astronomical algorithms to intelligently switch tracking modes, integrates mechanical self-locking and wind disturbance protection mechanisms, and supports fast charging and low power consumption states.
It achieves efficient and reliable energy capture, improves power generation efficiency by 30%-40%, reduces power consumption, has the ability to withstand harsh environments, supports fast charging protocols, features a lightweight design, adapts to changing weather, and protects device safety.
Smart Images
Figure CN121979293A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a solar fast charging device, and more particularly to an outdoor solar fast charging device and its operating method based on dual-axis solar tracking. Background Technology
[0002] Currently, outdoor solar charging solutions can be broadly categorized into two types. The first type is fixed solar charging devices, which typically mount solar panels on supports or tents at pre-adjusted angles. These devices are simple in structure and low in cost, but they cannot follow the sun's movement, resulting in short effective power generation time, low daily efficiency, and energy capture efficiency typically below 70%. The second type is single-axis (usually a horizontally placed single-axis) solar tracking devices. These systems use a rotating axis (usually a vertical axis) to roughly track the sun's azimuth angle. While relatively simple in structure, they cannot follow changes in the sun's altitude angle, especially in winter or high-latitude regions, where tracking accuracy is limited and efficiency improvement is not significant (approximately 10%-20%). Existing technologies have shortcomings such as… The following are the reasons: (1) Low energy capture efficiency. Fixed devices cannot utilize sunlight all day long, resulting in a short effective power generation window and a large amount of light energy not being utilized. Existing single-axis tracking schemes have a rough structure, cannot accurately track the sun, and lack an effective wind protection mechanism, making them prone to damage in the field. (2) Mismatch between power consumption and efficiency. Some electric tracking systems have high power consumption, and the increased power generation may not even be able to compensate for their own energy consumption, resulting in a loss. (3) Weak environmental adaptability. Lacking intelligent strategies, frequent rotation under complex lighting conditions such as cloudy days and overcast skies consumes energy instead of maximizing benefits. (4) Contradiction between portability and functionality. Highly efficient tracking systems are often complex and bulky, which conflicts with the lightweight and easy-to-store characteristics required for outdoor equipment. Summary of the Invention
[0003] This invention provides an outdoor solar fast charging device and its operating method based on dual-axis solar tracking, which solves the above-mentioned technical problems.
[0004] The present invention solves the above technical problems through the following technical solutions: An outdoor solar fast charging device based on dual-axis solar tracking is composed of a tracking execution unit, a sensing and control unit, and an energy conversion unit. The tracking actuator is located between the solar panel and the support base. The elevation angle servo in the tracking actuator is directly connected to the hinge on the back of the solar panel through the output shaft to control the pitch of the solar panel. The azimuth angle servo in the tracking actuator is connected to the base through a worm gear mechanism to drive the entire upper structure to rotate horizontally. The sensing and control unit is attached to the edge of the solar panel and flush with the surface of the solar panel to avoid shading itself; the four-quadrant photosensitive sensor of the sensing and control unit is connected to the main control microcontroller through the ADC interface; the inertial measurement unit of the sensing and control unit is connected to the main control microcontroller through the interface for calibrating the initial level; the main control microcontroller is connected to the elevation angle servo and azimuth angle servo through the pulse width modulation interface respectively. The energy conversion unit is integrated into the device base. The output of the solar panel is directly connected to the input of the maximum power point tracking controller. The output of the maximum power point tracking controller is connected to the lithium battery management circuit and the fast charging circuit respectively.
[0005] Electromagnetic brake pads are integrated inside the mechanical structure, which automatically lock when power is off to prevent wind disturbance.
[0006] A method for operating an outdoor solar fast charging device based on dual-axis solar tracking, characterized in that: The power-on initialization process of the outdoor solar fast charging device is as follows: After the main control microcontroller starts up, it first obtains the accurate latitude and longitude coordinates and world standard time from the GPS module, reads the data from the inertial measurement unit, calibrates the horizontal state of the device base to ensure the accuracy of the reference for subsequent angle calculations, and returns the servo motor to the safe initial position. The outdoor solar fast charging device is initially positioned using the following steps: The main control microcontroller calls the built-in solar position calculation algorithm, takes the current time and geographical location as input parameters, and calculates the theoretical azimuth and altitude angles of the sun relative to the device; The main control microcontroller drives the azimuth and altitude angle servos through PWM signals to rotate to the calculated theoretical angles, thus completing the initial positioning of the system.
[0007] The outdoor solar fast charging device is equipped with a light feedback fine tracking mode. After the initial positioning is completed, the system switches to a fine tracking mode with a four-quadrant photosensitive sensor as the core, forming a closed-loop control loop, and performs the following steps: The first step is for the main control microcontroller to continuously read the output voltage values of the four quadrants of the four-quadrant photosensitive sensor through the ADC interface to collect data. The second step is to calculate the offset of the light spot in the X and Y axes based on the voltage values in the four quadrants (V1, V2, V3, V4), and to perform deviation calculation. Δx = ( (V1 + V4) - (V2 + V3) ) / (V1 + V2 + V3 + V4), Δy = ( (V1 +V2) - (V3 + V4) ) / (V1 + V2 + V3 + V4); The third step is to input the offsets Δx and Δy into two independent digital PID (proportional-integral-derivative) controllers. The PID controllers output the corresponding control quantities to eliminate the deviation. The fourth step is to convert the PID control quantity into the duty cycle of the PWM signal, and drive the two servos to fine-tune in opposite directions until the center of the light spot coincides with the center of the sensor.
[0008] If the ambient light intensity is consistently higher than the set threshold and fluctuates only slightly, the system maintains the fine-tracking mode to achieve maximum power generation efficiency. If the ambient light intensity fluctuates, it is determined to be an invalid tracking environment, and the system immediately exits the fine-tracking mode and enters the low-power standby mode. If the light intensity is consistently lower than the threshold, the system also enters the low-power standby mode.
[0009] When continuous high-frequency vibration is detected and the amplitude exceeds the safety threshold, the interrupt service routine is immediately triggered. The interrupt service routine will immediately stop the servo motor action and activate the electromagnetic brake device to lock the mechanical structure. At the same time, the servo motor is controlled to rotate the solar panel to a safe posture with minimal wind resistance, thus maximizing the safety of the device.
[0010] The present invention has the following advantages: (1) Significantly improves power generation efficiency. Through high-precision dual-axis tracking, the normal of the solar panel is always aligned with the sun, and the energy capture efficiency is 30%-40% higher than that of the fixed type, realizing true "fast charging"; (2) High reliability and low power consumption. The intelligent tracking strategy of light intensity sensing and astronomical algorithm is adopted. It only starts when it is effective and its own power consumption is extremely low. It integrates mechanical self-locking and strong wind protection mechanism to adapt to harsh outdoor environment; (3) Intelligent energy management. The built-in MPPT controller ensures that the system always works at the optimal power point. It supports PD / QC and other fast charging protocols and can directly charge mobile phones, laptops and other devices quickly; (4) Lightweight and portable design. The compact dual-axis structure of hinge, linkage and micro servo motor combination realizes the unity of tracking function and portability. The volume after storage is comparable to that of a conventional power bank; (5) Environmental adaptability. The intelligent algorithm can identify rainy and cloudy weather and automatically switch to low power standby mode or stop meaningless rotation to save energy. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the composition of the present invention; Figure 2 This is a schematic diagram of the working principle of the present invention; Figure 3 This is a topology diagram of the present invention; Figure 4 This is the algorithm data logic diagram of the present invention. Detailed Implementation
[0012] The present invention will now be described in detail: An outdoor solar fast charging device based on dual-axis solar tracking consists of a tracking execution unit, a sensing and control unit, and an energy conversion unit. The tracking execution unit is located between the solar panel and the support base. The elevation angle servo is directly connected to the hinge on the back of the solar panel through the output shaft to control the pitch of the solar panel. The azimuth angle servo is connected to the base through a worm gear mechanism to drive the entire upper structure to rotate horizontally. The mechanical structure integrates an electromagnetic brake pad, which automatically locks when the power is off to prevent wind disturbance. The sensing and control unit is placed close to the edge of the solar panel, flush with the surface, to avoid shading itself; the four-quadrant photosensitive sensor is connected to the main control MCU via an ADC interface; the IMU inertial measurement unit is connected to the main control MCU via an I²C interface for calibrating the initial level; the main control MCU controls the elevation and azimuth servos via PWM interfaces respectively. The energy conversion unit is integrated into the device base; the output of the solar panel is directly connected to the input of the MPPT controller; the output of the MPPT controller is connected to the lithium battery management circuit and the USB Type-C fast charging circuit respectively; the lithium battery is connected to the USB fast charging circuit as an energy buffer.
[0013] A method for operating an outdoor solar fast charging device based on dual-axis solar tracking includes the following steps: Upon system power-on initialization: After the MCU starts up, it first obtains accurate latitude and longitude coordinates and UTC time from the GPS module; reads IMU (Inertial Measurement Unit) data, calibrates the horizontal state of the device base to ensure the accuracy of the reference for subsequent angle calculations; initializes all peripherals (servos, ADCs, PWMs, etc.), and returns the servos to their safe initial positions; This device uses a coarse positioning method based on astronomical algorithms: the main control MCU calls the built-in solar position calculation algorithm (such as the PSA algorithm or SPA algorithm); taking the current time (year, month, day, hour, minute, second) and geographical location (longitude, latitude) as input parameters, it calculates the theoretical azimuth and altitude angles of the sun relative to the device; the MCU drives the azimuth and altitude angle servos through PWM signals to rotate to the calculated theoretical angles, completing the coarse positioning of the system; this step allows the solar panel to quickly enter a roughly correct position, laying the foundation for subsequent fine tracking; The device's optical feedback fine tracking mode: After coarse positioning is completed, the system switches to fine tracking mode with a four-quadrant photosensitive sensor as the core, forming a closed-loop control loop. a. Data acquisition: The MCU continuously reads the output voltage values of the four quadrants of the four-quadrant photosensitive sensor through the ADC interface; b. Deviation Calculation: The algorithm calculates the offset of the light spot in the X and Y axis directions based on the voltage values in the four quadrants (V1, V2, V3, V4). Δx = ( (V1 + V4) - (V2 + V3) ) / (V1 + V2 + V3 + V4), Δy = ( (V1 +V2) - (V3 + V4) ) / (V1 + V2 + V3 + V4); c. PID Control Calculation: The offsets Δx and Δy are input into two independent digital PID (Proportional-Integral-Derivative) controllers. The PID controllers output corresponding control quantities to eliminate the deviation. d. Actuator drive: The PID control quantity is converted into the duty cycle of the PWM signal, which drives two servo motors to fine-tune in opposite directions until the center of the light spot coincides with the center of the sensor (i.e., Δx and Δy approach zero); this closed-loop mode can effectively compensate for the calculation error of the astronomical algorithm, mechanical installation error and external disturbance, and achieve the highest accuracy of solar tracking; Environmental Perception and Intelligent Mode Switching: The algorithm executes ambient light intensity monitoring in parallel. In a stable, strong light environment, when the ambient light intensity is consistently above a set threshold and fluctuates only slightly, the system maintains the fine-tracking mode with light feedback to achieve maximum power generation efficiency. In a fluctuating light environment (e.g., cloudy): when the algorithm detects drastic and frequent fluctuations in light intensity within a short period (e.g., more than N times / minute), it is determined to be an invalid tracking environment; the system immediately exits the fine-tracking mode and enters a low-power standby mode. In this mode, the MCU enters a sleep state, the servo motors stop moving, and only the timed interrupt wake-up function is retained, significantly reducing the system's own power consumption. In an insufficient light environment (e.g., dusk, rain): when the light intensity is consistently below the threshold, the system also enters a low-power standby mode; timed wake-up and judgment: in standby mode, the MCU wakes up once every certain period of time to re-detect the ambient light intensity; if the light intensity recovers and stabilizes, it jumps back to step 2 (coarse positioning) and restarts the tracking process; if it does not recover, it continues to sleep.
[0014] Safety protection mechanism: This mechanism has the highest interrupt priority and runs independently of the main process. The IMU unit monitors the vibration acceleration of the device in real time. When continuous high-frequency vibration is detected (judged as strong wind) and the amplitude exceeds the safety threshold, an interrupt is triggered immediately. The interrupt service routine will immediately stop the servo motor action and activate the electromagnetic brake device to lock the mechanical structure. At the same time, the servo motor is controlled to rotate the solar panel to a safe posture with minimal wind resistance (usually a horizontally laid-flat state) to maximize the safety of the device. When the IMU detects that the wind disturbance has disappeared and has been there for a period of time, the system automatically releases the brake lock and resumes the normal tracking process.
[0015] This device employs a dual-axis tracking method, utilizing an intelligent strategy of sensor fusion to achieve precise, efficient, and reliable tracking of the sun. The solar panel's power generation efficiency is highest when the incident light is parallel to the normal to the panel surface. The device uses a four-quadrant photosensitive sensor to detect the center deviation of the solar spot in real time. The principle is that when the solar spot is not centered on the sensor, the current generated in the four quadrants is different. By calculating the difference (Δx, Δy), the slight deviation of the sun's position can be obtained. This deviation signal is sent to the MCU, processed by a PID algorithm, and generates a PWM signal to drive two servo motors, forming a closed-loop control system until the deviation is eliminated. At the same time, the system integrates an astronomical algorithm based on time and GPS positioning as a backup strategy for coarse positioning and complex weather conditions, ensuring optimal decision-making under any circumstances.
Claims
1. An outdoor solar fast charging device based on dual-axis solar tracking, comprising a tracking execution unit, a sensing and control unit, and an energy conversion unit, characterized in that, The tracking actuator is located between the solar panel and the support base. The elevation angle servo in the tracking actuator is directly connected to the hinge on the back of the solar panel through the output shaft to control the pitch of the solar panel. The azimuth angle servo in the tracking actuator is connected to the base through a worm gear mechanism to drive the entire upper structure to rotate horizontally. The sensing and control unit is attached to the edge of the solar panel and flush with the surface of the solar panel to avoid shading itself; the four-quadrant photosensitive sensor of the sensing and control unit is connected to the main control microcontroller through the ADC interface; the inertial measurement unit of the sensing and control unit is connected to the main control microcontroller through the interface for calibrating the initial level; the main control microcontroller is connected to the elevation angle servo and azimuth angle servo through the pulse width modulation interface respectively. The energy conversion unit is integrated into the device base. The output of the solar panel is directly connected to the input of the maximum power point tracking controller. The output of the maximum power point tracking controller is connected to the lithium battery management circuit and the fast charging circuit respectively.
2. The outdoor solar fast charging device based on dual-axis solar tracking according to claim 1, characterized in that, Electromagnetic brake pads are integrated inside the mechanical structure, which automatically lock when power is off to prevent wind disturbance.
3. The operating method of an outdoor solar fast charging device based on dual-axis solar tracking as described in claim 1, characterized in that: The power-on initialization process of the outdoor solar fast charging device is as follows: After the main control microcontroller starts up, it first obtains the accurate latitude and longitude coordinates and world standard time from the GPS module, reads the data from the inertial measurement unit, calibrates the horizontal state of the device base to ensure the accuracy of the reference for subsequent angle calculations, and returns the servo motor to the safe initial position. The outdoor solar fast charging device is initially positioned using the following steps: The main control microcontroller calls the built-in solar position calculation algorithm, takes the current time and geographical location as input parameters, and calculates the theoretical azimuth and altitude angles of the sun relative to the device; The main control microcontroller drives the azimuth and altitude angle servos through PWM signals to rotate to the calculated theoretical angles, thus completing the initial positioning of the system.
4. The operating method of an outdoor solar fast charging device based on dual-axis solar tracking according to claim 3, characterized in that, The outdoor solar fast charging device is equipped with a light feedback fine tracking mode. After the initial positioning is completed, the system switches to a fine tracking mode with a four-quadrant photosensitive sensor as the core, forming a closed-loop control loop, and performs the following steps: The first step is for the main control microcontroller to continuously read the output voltage values of the four quadrants of the four-quadrant photosensitive sensor through the ADC interface to collect data. The second step is to calculate the offset of the light spot in the X and Y axes based on the voltage values in the four quadrants (V1, V2, V3, V4), and to perform deviation calculation. Δx = ( (V1 + V4) - (V2 + V3) ) / (V1 + V2 + V3 + V4), Δy = ( (V1 + V2) - (V3 + V4) ) / (V1 + V2 + V3 + V4); The third step is to input the offsets Δx and Δy into two independent digital PID (proportional-integral-derivative) controllers. The PID controllers output the corresponding control quantities to eliminate the deviation. The fourth step is to convert the PID control quantity into the duty cycle of the PWM signal, and drive the two servos to fine-tune in opposite directions until the center of the light spot coincides with the center of the sensor.
5. The operating method of an outdoor solar fast charging device based on dual-axis solar tracking according to claim 3 or 4, characterized in that, If the ambient light intensity is consistently higher than the set threshold and fluctuates only slightly, the system maintains the fine-tracking mode to achieve maximum power generation efficiency. If the ambient light intensity fluctuates, it is determined to be an invalid tracking environment, and the system immediately exits the fine-tracking mode and enters the low-power standby mode. If the light intensity is consistently lower than the threshold, the system also enters the low-power standby mode.
6. The operating method of an outdoor solar fast charging device based on dual-axis solar tracking according to claim 5, characterized in that, When continuous high-frequency vibration is detected and the amplitude exceeds the safety threshold, the interrupt service routine is immediately triggered. The interrupt service routine will immediately stop the servo motor action and activate the electromagnetic brake device to lock the mechanical structure. At the same time, the servo motor is controlled to rotate the solar panel to a safe posture with minimal wind resistance, thus maximizing the safety of the device.