Partitioned independent control photovoltaic carriage electric energy management system

Abstract

The application discloses a partition independent control photovoltaic compartment electric energy management system and method, and belongs to the technical field of photovoltaic vehicle energy. The outer surface of the photovoltaic compartment is divided into at least two independent light receiving areas, each area is respectively arranged with a photovoltaic subarray and is matched with an independent photovoltaic controller, and distributed architecture is adopted to realize partition maximum power tracking, thereby effectively avoiding the wood barrel effect of centralized MPPT. The system is provided with a central energy management unit, can identify local shadow and trigger global scanning of a power curve, the photovoltaic controller is integrated with a quick shutdown function, and high-voltage safety standards of an electric vehicle are met. The application can be linked with a compartment heat management system to realize collaborative control of heat dissipation and waste heat utilization. Compared with a traditional scheme, the application can improve power generation capacity by 30% to 50% under a complex illumination scene, the system has higher reliability and safety, and is suitable for new energy logistics vehicles, mobile homes, unmanned delivery vehicles and other vehicles loaded with full-coverage photovoltaics.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic integrated enclosures and vehicle-mounted intelligent power management technology, specifically to a zoned independent power management system and control method for a fully covered photovoltaic vehicle compartment. Background Technology

[0002] With the industrialization of new energy logistics vehicles, refrigerated trucks, recreational vehicles and unmanned delivery vehicles, integrating photovoltaic modules on the outer surface of the vehicle body has become a core technology for vehicle auxiliary energy replenishment. This can effectively alleviate the power supply pressure on the on-board energy storage system, extend the driving range of new energy vehicles, and reduce the overall energy consumption of the vehicle. The applicant's authorized utility model patent (ZL 202520348520.5) discloses a composite structure carriage, employing a cage-like frame and double-layer cavity structure design. Photovoltaic modules can be integrated into the outer panels of the carriage's top and sides, providing reliable structural support for the photovoltaic carriage's load-bearing capacity and the integrated installation of photovoltaic modules. This addresses the industry pain points of insufficient structural strength and poor heat dissipation of photovoltaic modules in traditional carriages. Building upon this, the applicant's earlier invention patent application (application number: 202610424696.3) discloses an energy-integrated photovoltaic box and intelligent thermal management method. Relying on a sandwich cavity and a bidirectional reversible heat exchange system, it achieves active heat dissipation and waste heat recovery of photovoltaic modules, effectively solving the thermal management problem of photovoltaic carriages. However, the aforementioned existing technologies only address the structural load-bearing and thermal management issues of the photovoltaic vehicle compartment, without optimizing for the refined control of onboard photovoltaic power generation. Currently, the industry generally adopts a centralized control scheme for photovoltaic vehicle compartments, using a single top mounting surface. This approach incurs costs far exceeding the value of the photovoltaic panels themselves, failing to achieve breakthroughs in traditional technologies such as expansion and light tracking. All photovoltaic modules on the outer surface of the compartment are connected in series and then linked to a single MPPT controller for power tracking. This solution operates stably under ideal laboratory conditions with a fixed angle and uniform illumination, but it cannot adapt to the complex scenarios of actual vehicle operation. During vehicle movement and parking, the intensity and angle of sunlight vary greatly across different illuminated surfaces such as the roof, left side, right side, front, and rear of the vehicle. A centralized architecture suffers from a severe "weakest link" effect, where the overall system output power is limited by the photovoltaic modules with the worst illumination and lowest output current, resulting in a significant waste of power generation potential. Actual measurement data confirms that in typical urban parking scenarios with complex lighting conditions, the power generation of a traditional centralized MPPT (Multi-Level Photovoltaic Power Supply) solution is 30% to 50% lower than that of a zoned, independent MPPT solution. Meanwhile, traditional centralized MPPT solutions cannot adapt to dynamic vehicle shadow scenarios. They are prone to getting stuck in local maximum power points due to instantaneous and dynamic shadows created by trees, overpasses, and adjacent vehicles, making it difficult to accurately locate the global maximum power point and resulting in poor power generation stability. Furthermore, existing technologies cannot achieve coordinated operation between the photovoltaic power generation system and the vehicle's thermal management system, failing to form an integrated intelligent control system of "power generation optimization + thermal energy regulation," leading to high overall vehicle energy consumption and low energy utilization efficiency. In response to the numerous shortcomings of existing technologies, the applicant has further developed a refined power control scheme based on the existing photovoltaic vehicle structure and core thermal management technologies. The applicant proposes a photovoltaic vehicle power management system and method with independent MPPT control for each zone, which realizes the intelligent and refined upgrade of photovoltaic vehicle power management and maximizes the release of vehicle-mounted photovoltaic power generation efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a photovoltaic vehicle compartment power management system and method with independent zone control, addressing the technical shortcomings of existing centralized control schemes such as low power generation efficiency, poor tracking accuracy, lack of fault isolation capability, and inability to work collaboratively with thermal management systems under complex vehicle lighting and dynamic shading conditions. This invention combines the applicant's prior patents on composite vehicle compartment structure and photovoltaic enclosure thermal management to construct an integrated technical system of "structural load-bearing capacity + thermal energy management + refined power regulation," comprehensively improving the energy utilization efficiency and operational stability of the photovoltaic vehicle compartment.

[0004] Technical solution To achieve the above objectives, the present invention adopts the following technical solution: A photovoltaic vehicle compartment power management system with independent zone control includes a photovoltaic vehicle compartment, multiple photovoltaic sub-arrays, and supporting photovoltaic controllers. The outer surface of the photovoltaic vehicle compartment is divided into at least two independent light-receiving areas, including but not limited to the roof area, left side area, right side area, front area, and rear area. At least one photovoltaic sub-array is fixedly arranged in each independent light-receiving area, and each photovoltaic sub-array is independently electrically connected to at least one photovoltaic controller. The power output terminals of all photovoltaic controllers are connected to the on-board energy storage system or vehicle power system in parallel or series. The photovoltaic controller is a distributed independent control unit that can collect the light intensity, ambient temperature, and output voltage and current parameters of the corresponding light-receiving area in real time, and independently adjust the operating voltage and operating current of the corresponding photovoltaic sub-array so that the photovoltaic sub-array can continuously operate at the maximum power point under the current operating conditions. For large sun-receiving areas such as vehicle roofs, the photovoltaic subarrays within the area can be further divided into multiple independent electrical segments. Each electrical segment is equipped with a separate photovoltaic controller, enabling distributed, segmented MPPT control within the area and avoiding the problem of sudden power drops across the entire area caused by localized shading. When a single photovoltaic subarray is equipped with multiple photovoltaic controllers, the controllers work collaboratively through current sharing mode or segmented tracking mode to ensure optimal overall power generation efficiency of the subarray. The photovoltaic controller adopts a masterless distributed architecture, with each controller operating independently and without interference. A single point of failure only affects the power generation of the corresponding local area, preventing system-wide failure and significantly improving system reliability. The controller incorporates a high-precision MPPT algorithm with a tracking frequency ≥10Hz and tracking accuracy ≥99%, enabling rapid response to changes in sunlight. The system is also equipped with a central energy management unit, which establishes real-time communication with all photovoltaic controllers through a CAN bus or digital signal line. It synchronously collects operating data such as power generation, voltage, current, and temperature of each photovoltaic subarray. Combined with the SOC state of charge of the on-board energy storage system and the real-time load power demand of the vehicle, it dynamically adjusts the working mode of each photovoltaic controller and issues global scanning commands as needed to realize intelligent power scheduling of the entire system. The central energy management unit features intelligent shading recognition, monitoring power change trends in each sun-receiving area in real time. When it detects a power drop exceeding 30% in a single area within 5 seconds, with no synchronous power decay in adjacent areas, it accurately determines that local shading exists in that area and immediately sends a global scan command to the corresponding photovoltaic controller. The photovoltaic controller initiates a full-segment power-voltage curve scan, locates the global maximum power point, and automatically switches to a conventional local tracking mode to ensure power generation efficiency under complex shading conditions. The photovoltaic controller integrates high-voltage fast shutdown protection function, which can receive vehicle collision signals, high-voltage insulation fault signals, and manual emergency stop signals in real time. After receiving the trigger signal, it quickly cuts off the power output of the corresponding photovoltaic sub-array within 100 milliseconds, fully meeting the mandatory high-voltage safety standard for electric vehicles GB / T 18384-2020, and ensuring the safety of vehicle operation and manual maintenance. This invention also provides a photovoltaic vehicle compartment power management method with independent zone control, based on the above system, including core steps such as independent zone tracking, global shading scanning, fault hibernation protection, and thermoelectric coordinated regulation, as detailed below: Step A: The outer surface of the photovoltaic vehicle is pre-divided into N independent light-receiving areas, where N≥2. Each light-receiving area is matched with an independent photovoltaic sub-array and at least one dedicated photovoltaic controller. Through physical and electrical isolation, the power generation of each area is not coupled or interfered with each other. Step B: Each photovoltaic controller independently collects the real-time voltage U and current I of the corresponding photovoltaic subarray, calculates the real-time power generation P=U×I, and dynamically tracks the maximum power point through the perturbation observation method or the incremental conductance method to optimize the subarray's operating status in real time. Step C: Each photovoltaic controller completes the voltage stabilization and regulation conversion of the power, converting the power at the maximum power point into a voltage level suitable for the vehicle's common DC bus, and directly connecting it to the bus to charge the energy storage system or supply power to the vehicle's electrical equipment. Step D: The central energy management unit aggregates the operating data of all photovoltaic controllers, determines local shading conditions by power change rate and regional power difference characteristics, and triggers the corresponding controller to perform a global scan operation to avoid local optimization traps. Step E: The photovoltaic controller monitors the open-circuit voltage and output current of the subarray in real time. When the open-circuit voltage is continuously lower than the preset threshold and the output current returns to zero, it is determined that the area is severely shaded or the module is faulty. The controller automatically enters standby sleep mode and uploads the fault code and location information to the central energy management unit for quick operation and maintenance troubleshooting. Meanwhile, this method adds collaborative control logic with the photovoltaic box thermal management system: when the power generation of a single solar-receiving area drops by more than 50% for more than 10 seconds, it is determined that the area has low irradiance and no heat demand. The controller sends a low irradiance signal to the thermal management system, and the thermal management system adaptively reduces the heat dissipation power of the area to reduce ineffective energy consumption. When the low-temperature carriage needs heating in winter, the central energy management unit prioritizes the use of waste heat from the solar-receiving area with the highest current power generation efficiency and component temperature, and transports it to the area in the carriage that needs heating through the thermal management system to realize waste heat recovery and utilization, and reduce the overall vehicle heating energy consumption.

[0005] Beneficial effects 1. Significantly improves power generation under complex lighting conditions. This invention adopts a zoned independent control architecture, where each illuminated area independently tracks its maximum power point, completely eliminating the bottleneck effect of traditional centralized control. Local shading only affects the power generation of a single area, while the remaining areas can maintain full power output. Actual test data shows that under typical urban parking conditions, the power generation of this invention is 30%–50% higher than traditional solutions, and in heavily shaded scenarios, the power generation improvement can reach over 80%, significantly optimizing power generation efficiency. 2. Adapts to dynamic vehicle shadow scenarios with high tracking accuracy. The photovoltaic controller has a high-frequency tracking capability of over 10Hz. Combined with the intelligent shadow recognition and global scanning mechanism of the central energy management unit, it can quickly respond to dynamic and instantaneous shadow changes during vehicle movement, accurately locate the global maximum power point, avoid the algorithm getting stuck in local optima, and ensure the stability of power generation under all operating conditions. 3. Excellent system security and reliability. This invention adopts a distributed masterless architecture, which has natural fault isolation capabilities. Short circuits, open circuits, or controller failures in a single area component will not cause the entire system to shut down. The accompanying 100ms fast shutdown function complies with national high-voltage safety specifications, can quickly cut off faulty circuits, avoid high-voltage safety risks, and is suitable for complex vehicle-mounted application scenarios. 4. Achieve integrated thermal and power synergistic management. This invention is deeply integrated with the applicant's prior photovoltaic box bidirectional thermal management system, which can adaptively adjust the heat dissipation power according to regional irradiance and power generation status, and recover waste heat from the modules as needed, realizing integrated control of "precise optimization on the power generation side + intelligent regulation on the heat consumption side", effectively reducing the overall energy consumption of the vehicle and improving the overall energy utilization rate. 5. Modular design with strong expandability and adaptability. Different light-receiving areas can be flexibly equipped with flexible thin-film photovoltaic modules or rigid crystalline silicon photovoltaic modules according to the shape, area, and orientation of the vehicle. The parameters of each controller can be configured and adjusted independently. Large areas can be further optimized for power generation performance by subdividing electrical sections and adding controllers. It can be adapted to photovoltaic vehicles of various sizes and shapes, with extremely strong customization adaptability. Attached Figure Description

[0006] Figure 1 This is a schematic diagram showing the division of the light-receiving area of ​​the photovoltaic vehicle body according to the present invention (four independent areas: roof, left side, right side, and front). Figure 2 The diagram shows the topology of the partitioned system of this invention (four photovoltaic sub-arrays → each sub-array is connected to at least one photovoltaic controller → common DC bus → energy storage battery / load). Figure 3 This is a comparison chart of the power-voltage curves of a centralized MPPT and the partitioned MPPT of this invention under localized shadow scenes. Figure 4 This is a flowchart of the global scan control process of the present invention. Figure 5 This is a signal interaction diagram showing the collaborative operation of the present invention and the thermal management system. Detailed Implementation

[0007] Example 1 (System Structure Example) This embodiment provides a photovoltaic carriage power management system with independent zone control, adapted to the applicant's authorized composite structure carriage (patent number: ZL 202520348520.5), with the specific structural configuration as follows: The outer surface of the photovoltaic vehicle is divided into four isolated, independent light-receiving areas: the roof area, the left side area, the right side area, and the front area. Each area is electrically and physically isolated through physical gaps to prevent power clamping interference between areas. The roof area uses a rigid monocrystalline silicon photovoltaic sub-array, while the left, right, and front areas use flexible CIGS thin-film photovoltaic sub-arrays. The electrical parameters of the photovoltaic sub-arrays in each area are shown in the table below. The roof area is relatively large and is prone to uneven lighting due to sunroofs and onboard equipment. Therefore, the roof photovoltaic sub-array is divided into three independent electrical sections, each equipped with an independent photovoltaic controller, for a total of 3 photovoltaic controllers. A dedicated photovoltaic controller is also configured for the left, right and front areas, for a total of 6 photovoltaic controllers in the system. The photovoltaic controller selected is model MS-MT40A-480, with an input voltage adaptability of 60-500V, MPPT tracking accuracy of 99.5%, tracking frequency of 20Hz, and built-in 100ms fast shutdown protection function. All photovoltaic controller outputs are connected in parallel to a 48V common DC bus, which is then connected to a 48V / 200Ah vehicle-mounted lithium iron phosphate battery pack, DC air conditioner, DC-DC converter, and other vehicle-mounted electrical equipment. The central energy management unit uses an STM32F407 microcontroller and communicates in real time with six photovoltaic controllers via a CAN bus to collect power generation and temperature parameters from each area. At the same time, it communicates with the vehicle's VCU and thermal management controller via an independent CAN bus to achieve coordinated operation between the power management and thermal management systems.

[0008] Example 2 (Control Method Example) This embodiment uses a typical scenario where a vehicle is parked on the roadside and the left side of the area is partially obscured by a building to illustrate the partitioned MPPT control method of the present invention in detail: Initial unobstructed operation: The entire vehicle is well-lit, and all photovoltaic controllers independently track the maximum power point of their respective sub-arrays. The roof sub-array outputs 1600W, the left and right sub-arrays each output 700W, the front sub-array outputs 200W, and the total power generation of the system is 2600W. The system is operating stably. Dynamic shading phase: As the vehicle gradually enters the area covered by the building's shadow on the left, the photovoltaic controller on the left monitors in real time that the power generation drops rapidly from 700W to 200W. The controller dynamically adjusts the operating voltage through the perturbation observation method and continuously tracks the local maximum power point under the current low light conditions to achieve dynamic adaptation. Stable operation under shadow conditions: The left side is completely covered by shadow, and the power generation is stable at around 100W. The roof, right side, and front areas are unobstructed, and the power output is continuously at full power. Compared to the traditional centralized MPPT solution, the series architecture of all components is limited by the low current on the left side, and the total power is less than 500W. This invention uses independent control of each zone, so that each zone does not interfere with each other, and the total system power can still reach 2600W, completely avoiding the bottleneck effect loss. Global scan triggering and execution: The shadow occlusion in the left area caused the power-voltage curve of the subarray to show multiple peak characteristics. The central energy management unit detected that the power drop in the left area exceeded 30% within 5 seconds, and the power in the adjacent right area did not drop synchronously. It was determined that there was local shadow occlusion and a global scan command was issued. After receiving the command, the photovoltaic controller on the left uses the 120V open-circuit voltage as a reference and performs a linear scan from 20%Voc (24V) to 80%Voc (96V) with a scan step size of 1.2V (1%Voc). At each step size, it stays for 2 MPPT tracking cycles (0.1 seconds) and records the power data. After the scan is completed, the voltage corresponding to the maximum power point is selected as the working voltage. The perturbation observation method is switched to continue local tracking to ensure the optimal power generation state under complex shading conditions.

Claims

1. A photovoltaic vehicle compartment power management system with independent zone control, characterized in that, include: The outer surface of the photovoltaic vehicle body is divided into at least two independent light-receiving areas; at least one photovoltaic sub-array is fixedly laid in each light-receiving area; each photovoltaic sub-array is independently electrically connected to at least one photovoltaic controller; the power output terminals of all photovoltaic controllers are connected in parallel or in series to the on-board energy storage system or the vehicle's power system. The photovoltaic controller detects the light intensity and temperature of the corresponding light-receiving area, as well as the output voltage and current of the photovoltaic subarray, in real time, and independently adjusts the operating point of the corresponding photovoltaic subarray so that the photovoltaic subarray always operates at the maximum power point under the current environmental conditions.

2. The photovoltaic vehicle compartment power management system with independent zone control according to claim 1, characterized in that: The light-receiving area includes at least the roof area, the left side area, the right side area, and the front area. Each light-receiving area is isolated from the others by physical gaps or electrical isolation structures to avoid power interference caused by uneven illumination in different areas.

3. The photovoltaic vehicle compartment power management system with independent zone control according to claim 1, characterized in that: The photovoltaic controller adopts a distributed architecture, with each photovoltaic controller having an independent maximum power point tracking algorithm built in, a tracking frequency ≥10Hz, and a tracking accuracy ≥99%; there is no master-slave dependency relationship between the photovoltaic controllers; when a single photovoltaic subarray is electrically connected to multiple photovoltaic controllers, the multiple photovoltaic controllers work together in a current sharing mode or a segmented tracking mode.

4. The photovoltaic vehicle compartment power management system with independent zone control according to claim 1, characterized in that: It also includes a central energy management unit, which establishes a communication connection with each photovoltaic controller through a CAN bus or digital signal line, collects the power generation, voltage, current and temperature operating parameters of each photovoltaic subarray in real time, and dynamically adjusts the working mode of each photovoltaic controller or issues a global scan command according to the state of charge of the on-board energy storage system and the power demand of the vehicle load.

5. The photovoltaic vehicle compartment power management system with independent zone control according to claim 4, characterized in that: When the central energy management unit detects that the power generation of a certain light-receiving area decreases by more than 30% within 5 seconds, and the power generation of adjacent light-receiving areas does not decrease synchronously, it determines that there is a local shading in the area and sends a global scan command to the corresponding photovoltaic controller. After the photovoltaic controller completes the global scan of the power-voltage curve and locates the global maximum power point, it automatically resumes the local maximum power tracking mode.

6. The photovoltaic vehicle compartment power management system with independent zone control according to claim 1, characterized in that: The photovoltaic subarray adopts flexible thin-film photovoltaic modules or rigid crystalline silicon photovoltaic modules. The type of photovoltaic modules and the number of series and parallel connections in different light-receiving areas can be independently matched and designed according to the shape, area and light-receiving orientation of the corresponding carriage exterior surface.

7. The photovoltaic vehicle compartment power management system with independent zone control according to claim 1, characterized in that: The photovoltaic controller integrates a fast shutdown function. When it receives a vehicle collision signal, a high-voltage insulation fault signal, or a manual emergency stop signal, it can cut off the power output of the corresponding photovoltaic sub-array within 100 milliseconds, which complies with the GB / T 18384-2020 electric vehicle high-voltage safety standard.

8. A partition-independent control method based on the system according to any one of claims 1-7, characterized in that, Includes the following steps: Step A: Divide the outer surface of the photovoltaic vehicle into N independent light-receiving areas, where N≥2. Each light-receiving area is equipped with a set of photovoltaic sub-arrays and at least one independent photovoltaic controller to achieve independent power generation in each area without interference. Step B: Each photovoltaic controller independently detects the real-time voltage U and current I of the corresponding photovoltaic subarray, calculates the real-time power generation P=U×I, and uses the perturbation observation method or the conductance increment method to track the maximum power point of the corresponding photovoltaic subarray in real time. Step C: Each photovoltaic controller converts the maximum power point electrical energy into electrical energy adapted to the vehicle bus voltage and outputs it to the common DC bus or directly powers the vehicle's electrical equipment; Step D: The central energy management unit collects the operating data of each photovoltaic controller in real time, and determines whether there is shading in the area by the power change trend. If shading is determined to exist, the corresponding photovoltaic controller is triggered to perform a global scan operation. Step E: When the photovoltaic controller detects that the open-circuit voltage of the corresponding photovoltaic subarray is continuously lower than the preset threshold and the output current is zero, it determines that there is severe shading or component failure in the area. The controller automatically enters standby sleep mode and uploads the fault information to the central energy management unit.

9. The partition-independent control method according to claim 8, characterized in that: The specific execution method of the global scan in step D is as follows: The photovoltaic controller linearly scans the operating voltage of the corresponding photovoltaic subarray from 20% to 80% of the open-circuit voltage Voc, with a scan step size ≤ 1% Voc. At each scan step size, it stays for at least two MPPT tracking cycles and records the corresponding power generation value. After the scan is completed, the voltage corresponding to the maximum power value is selected as the optimal operating voltage, and the perturbation observation method is switched to perform local maximum power tracking.

10. The partition-independent control method according to claim 8, characterized in that: It also includes coordinated control steps with the photovoltaic enclosure thermal management system: When the photovoltaic controller detects that the power generation of the corresponding solar-receiving area drops by more than 50% and lasts for more than 10 seconds, it sends a low-irradiance signal to the thermal management system. The thermal management system then adaptively reduces the heat dissipation power of the corresponding area. When the thermal management system needs to absorb the waste heat from the photovoltaic modules to heat the carriage, the central energy management unit prioritizes the use of the waste heat from the solar-receiving area with the highest power generation efficiency and delivers the waste heat to the space in the carriage that needs heat, thus achieving thermo-electric energy-saving control.

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