A light storage oil multi-energy complementary direct current power supply system for monitoring buoy

Abstract

The application provides a kind of light oil storage multi-function complementary direct current power supply system for monitoring buoy, relates to new energy power supply technical field, including photovoltaic power generation system, diesel power generation system, energy storage battery system, energy management module, DC bus and load equipment;Photovoltaic power generation system is composed of flexible photovoltaic panel and MPPT solar controller in series, the output end of flexible photovoltaic panel is connected with the input end of MPPT solar controller, the output end of MPPT solar controller is connected with the input end of DC bus, and flexible photovoltaic panel outputs 150V direct current.The system of the application takes 72V DC bus as the core, realizes voltage adaptation and stable output through various controllers and converters, adapts to the power demand of different load equipment of buoy, solves the problem of single power supply mode limited by weather and endurance, has the advantages of high power supply reliability, high energy utilization efficiency and convenient installation and maintenance, meets the continuous power supply demand of long-time off-shore deployment of buoy.

Description

Technical Field

[0001] This invention relates to the field of new energy power supply technology, specifically to a photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys. Background Technology

[0002] Existing buoy power supply mostly adopts a single energy mode, relying solely on photovoltaic power generation or diesel power generation. Among them, photovoltaic power generation systems are significantly affected by changes in water weather and the alternation of day and night, resulting in large fluctuations in power generation and an inability to provide continuous power during cloudy or rainy weather or at night; diesel power generation systems suffer from high fuel consumption and large carbon emissions, and are prone to mechanical failures during long-term operation, leading to high maintenance costs; single energy storage battery systems have limited energy storage capacity, and are prone to power outages due to depletion of power during long-term offshore operation or high-load conditions.

[0003] The aforementioned single power supply mode is difficult to guarantee the continuous and stable operation of the buoy system in complex aquatic environments, continuous severe weather, or long-term offshore deployment scenarios. In severe cases, it may lead to system paralysis and fail to meet the power supply needs of buoys in practical applications. Therefore, there is an urgent need for a photovoltaic-oil storage multi-energy complementary DC power supply system and device for monitoring buoys to solve the above technical problems. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a photovoltaic, energy storage, and diesel multi-energy complementary DC power supply system for monitoring buoys. This system integrates photovoltaic, energy storage, and diesel energy, and achieves dynamic switching and coordinated power supply through an energy management module. This effectively solves the problem of weather and range limitations under a single power supply mode, enabling continuous power supply for buoys deployed offshore for extended periods. By adopting a photovoltaic-first power supply strategy, renewable energy can be fully utilized. Combined with the peak-shaving and valley-filling effect of the energy storage battery pack, the starting frequency of the diesel generator is effectively reduced, thereby reducing fuel consumption and carbon emissions, thus conforming to the concept of green and low-carbon development. Furthermore, the ingenious energy storage design minimizes the start-stop impact of the diesel generator, extending its service life.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys includes a photovoltaic power generation system, a diesel power generation system, an energy storage battery system, an energy management module, a DC bus, and load equipment; The photovoltaic power generation system consists of a flexible photovoltaic panel and an MPPT solar controller connected in series. The output end of the flexible photovoltaic panel is connected to the input end of the MPPT solar controller, and the output end of the MPPT solar controller is connected to the input end of the DC bus. The flexible photovoltaic panel outputs a first voltage DC power, which is stepped down by the MPPT solar controller and then outputs a second voltage DC power to the DC bus. The diesel generator system includes a diesel generator and an AC / DC module. The output terminal of the diesel generator is connected to the input terminal of the AC / DC module, and the output terminal of the AC / DC module is connected to the input terminal of the DC bus. The diesel generator outputs 220V AC power, which is rectified and converted by the AC / DC module to output a second voltage DC power to the DC bus. The energy storage battery system includes a lithium battery pack and a bidirectional DC-DC converter. The output of the lithium battery pack is connected to the input of the bidirectional DC-DC converter, and the output of the bidirectional DC-DC converter is connected to the input of the DC bus. The bidirectional DC-DC converter realizes bidirectional voltage conversion between the third voltage DC output of the lithium battery pack and the second voltage DC of the DC bus. The energy management module is used to control and manage the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system; The DC bus output is connected to the load device input, enabling efficient connection between multiple power sources and the load device.

[0006] The aforementioned energy management module includes voltage and current sensors, a microcontroller controller, and an actuator. The voltage and current sensors are connected to the output terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively. The output terminals of the voltage and current sensors are connected to the input terminals of the microcontroller controller, and the output terminals of the microcontroller controller are connected to the input terminals of the actuator. The actuator is connected to the control terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively.

[0007] The aforementioned multiple flexible photovoltaic panels are connected in series to form a photovoltaic module, and the output end of the photovoltaic module is connected to the input end of the MPPT solar controller.

[0008] The aforementioned MPPT solar controller has two output interfaces. One output interface is connected to the DC bus input terminal, and the other output interface is connected to the lithium battery pack input terminal through a bidirectional DC-DC converter, realizing a connection structure that simultaneously supplies power to the load device and charges the lithium battery pack.

[0009] The aforementioned bidirectional DC-DC converter is configured with boost mode and buck mode. In boost mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the lithium battery pack, and the output terminal is connected to the input terminal of the DC bus, boosting the third voltage DC to the second voltage DC. In buck mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the DC bus, and the output terminal is connected to the input terminal of the lithium battery pack, bucking the second voltage DC to the third voltage DC.

[0010] The aforementioned voltage and current sensors include a photovoltaic voltage and current sensor, a diesel generator voltage and current sensor, and a battery voltage and current sensor. The photovoltaic voltage and current sensor is connected in series between the MPPT solar controller and the DC bus, the diesel generator voltage and current sensor is connected in series between the AC / DC module and the DC bus, and the battery voltage and current sensor is connected in series between the bidirectional DC-DC converter and the lithium battery pack.

[0011] The aforementioned actuators include a photovoltaic switch, a diesel generator switch, and a battery switch. The photovoltaic switch is connected in series between the MPPT solar controller and the DC bus, the diesel generator switch is connected in series between the AC / DC module and the DC bus, and the battery switch is connected in series between the bidirectional DC-DC converter and the DC bus. The control terminals of each switch are connected to the output terminal of the microcontroller.

[0012] 8. A multi-energy complementary DC power supply system for monitoring buoys using photoelectric and oil storage as described in claim 2, characterized in that the load equipment includes observation sensors, communication equipment, and low-voltage DC power loads, and the load equipment is connected to the DC bus through corresponding DC / DC converters, including 48V / 20A converters, 24V / 20A converters, 12V / 20A converters, and 5V / 20A converters.

[0013] The input terminal of the aforementioned 48V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 48V load device input terminal; the input terminal of the 24V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 24V load device input terminal; the input terminal of the 12V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 12V load device input terminal; the input terminal of the 5V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 5V load device input terminal.

[0014] The aforementioned lithium battery pack is connected to a bidirectional DC-DC converter via a battery management unit, and the output of the battery management unit is connected to the input of a microcontroller.

[0015] The aforementioned DC bus is equipped with a voltage stabilizer. The input terminal of the voltage stabilizer is connected to the output terminal of each power supply module, the output terminal of the voltage stabilizer is connected to the input terminal of the load device, and the control terminal of the voltage stabilizer is connected to the output terminal of the microcontroller.

[0016] In a preferred embodiment, a supercapacitor energy storage module is connected in series between the output terminal of the AC / DC module of the aforementioned diesel generator system and the DC bus. The supercapacitor energy storage module includes a supercapacitor bank and an adaptive DC-DC converter. The DC-DC converter enables voltage adaptation between the supercapacitor bank and the second voltage DC bus.

[0017] The diesel generator described above has a micro-start fuel control valve in its fuel circuit and a start-stop buffer clutch on its main shaft. The micro-start fuel control valve, the start-stop buffer clutch, and the supercapacitor energy storage module are all electrically connected to the microcontroller. The lithium battery pack communicates with the microcontroller controller through the battery management unit. The microcontroller controller outputs control commands based on the remaining capacity of the lithium battery pack and the real-time power output of the load to realize the micro-start fast charging control of the diesel generator.

[0018] The supercapacitor bank mentioned above is a 16V / 500F capacitor module. The adapter DC-DC converter is a boost DC-DC converter, which can boost the 16V DC output of the supercapacitor bank to a second voltage of 72V DC and connect it to the DC bus. The adapter DC-DC converter is equipped with a charge and discharge protection module to limit the charge and discharge current and voltage of the supercapacitor bank.

[0019] The aforementioned micro-start fuel control valve is an electronic proportional fuel control valve, which is linked to the fuel pump of the diesel generator. The microcontroller controller can adjust the fuel supply of the diesel generator through the micro-start fuel control valve, so as to achieve precise control of the generator output power within the range of 80%-100% of the rated power.

[0020] The aforementioned start-stop buffer clutch is an electromagnetic buffer clutch. Its engagement and disengagement are controlled by electrical signals from a microcontroller. When the clutch is engaged, it enables shock-free power output from the generator main shaft, and when it is disengaged, it enables the generator to stop without load.

[0021] The aforementioned supercapacitor energy storage module and lithium battery pack form a hybrid energy storage structure. Both interact with a bidirectional DC-DC converter to exchange electrical energy. The supercapacitor energy storage module is used to quickly absorb excess electrical energy when the diesel generator is running at full load, and then slowly charge the lithium battery pack through the bidirectional DC-DC converter.

[0022] The aforementioned microcontroller controller has a built-in diesel generator micro-start fast charging control program. It sets the two conditions for starting the diesel generator as the remaining capacity of the lithium battery < 40% and the real-time load power > the photovoltaic output power, and sets the remaining capacity of the lithium battery ≥ 80% or the supercapacitor bank full capacity as the diesel generator shutdown condition.

[0023] The photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys mentioned in this invention has the following beneficial effects: 1. The invention has high power supply reliability: It integrates three energy sources, namely photovoltaic, energy storage and diesel, and realizes dynamic switching and coordinated power supply through the energy management module. It effectively solves the problem of being limited by weather and endurance under the single power supply mode, so as to meet the continuous power supply needs of buoys for long-term offshore deployment.

[0024] 2. This invention is highly efficient in energy utilization: It adopts a photovoltaic-first power supply strategy, which can make full use of renewable energy. Combined with the peak shaving and valley filling effect of energy storage battery packs, it can effectively reduce the starting frequency of diesel generators, thereby reducing fuel consumption and carbon emissions, and thus conforming to the concept of green and low-carbon development.

[0025] 3. The present invention is easy to install and maintain: The system adopts a modular design, and each functional module is connected through a standard DC bus. The wiring is simple and the structure is highly integrated, which makes it easy to install and arrange in the limited space of the buoy. At the same time, it effectively reduces redundant equipment, thereby effectively reducing the frequency of manual inspection and maintenance costs.

[0026] 4. Through the fast-charging buffering effect of the supercapacitor energy storage module, the diesel generator only operates under full load for a short time, increasing the power generation efficiency from low load. Combined with the dual-condition start-up logic, the number of generator start-stop cycles is reduced, overall fuel consumption is reduced, and carbon emissions are reduced simultaneously, which is in line with the concept of green and low-carbon development.

[0027] 5. The start-stop buffer clutch enables the generator to start and stop without impact and to stop without load, avoiding severe wear of mechanical parts caused by frequent start-stop, reducing the probability of generator failure, greatly extending its service life, and reducing the frequency and cost of offshore buoy maintenance.

[0028] 6. The supercapacitor energy storage module first absorbs electrical energy quickly and then slowly charges the lithium battery pack, eliminating the current surge problem of direct charging of diesel generators, avoiding the impact of lithium battery charging and discharging, and improving battery cycle life.

[0029] 7. The supercapacitor energy storage module, as a temporary energy storage unit, can quickly respond to the power demand of the DC bus, offset the power fluctuations caused by sudden load changes or energy switching, and, together with the precise power regulation of the diesel generator, further improve the voltage stability of the DC bus, ensuring the reliable operation of the buoy's precision load. Attached Figure Description

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the overall module connection structure of the system of the present invention; Figure 2 This is a schematic diagram of the overall module connection structure of the system of the present invention in a preferred embodiment. Detailed Implementation

[0031] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0032] like Figure 1 As shown, a photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys includes a photovoltaic power generation system, a diesel power generation system, an energy storage battery system, an energy management module, a DC bus, and load equipment. The photovoltaic power generation system consists of a flexible photovoltaic panel and an MPPT solar controller connected in series. The output end of the flexible photovoltaic panel is connected to the input end of the MPPT solar controller, and the output end of the MPPT solar controller is connected to the input end of the DC bus. The flexible photovoltaic panel outputs 150V DC power, which is stepped down by the MPPT solar controller and outputs 72V DC power to the DC bus. The diesel generator system includes a diesel generator and an AC / DC module. The output terminal of the diesel generator is connected to the input terminal of the AC / DC module, and the output terminal of the AC / DC module is connected to the input terminal of the DC bus. The diesel generator outputs 220V AC power, which is rectified and converted by the AC / DC module to output 72V DC power to the DC bus. The energy storage battery system includes a lithium battery pack and a bidirectional DC-DC converter. The output of the lithium battery pack is connected to the input of the bidirectional DC-DC converter, and the output of the bidirectional DC-DC converter is connected to the input of the DC bus. The bidirectional DC-DC converter realizes bidirectional voltage conversion between the 48V DC output of the lithium battery pack and the 72V DC output of the DC bus. The energy management module is used to control and manage the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system; The DC bus output is connected to the load device input, enabling efficient connection between multiple power sources and the load device.

[0033] The aforementioned energy management module includes voltage and current sensors, a microcontroller controller, and an actuator. The voltage and current sensors are connected to the output terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively. The output terminals of the voltage and current sensors are connected to the input terminals of the microcontroller controller, and the output terminals of the microcontroller controller are connected to the input terminals of the actuator. The actuator is connected to the control terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively.

[0034] The aforementioned flexible photovoltaic panels are 18V / 330W specifications. Multiple flexible photovoltaic panels are connected in series to form a photovoltaic module. The output terminal of the photovoltaic module is connected to the input terminal of the MPPT solar controller, and the output voltage of the photovoltaic module after series connection is 150V.

[0035] The aforementioned MPPT solar controller has two output interfaces. One output interface is connected to the DC bus input terminal, and the other output interface is connected to the lithium battery pack input terminal through a bidirectional DC-DC converter, realizing a connection structure that simultaneously supplies power to the load device and charges the lithium battery pack.

[0036] The aforementioned bidirectional DC-DC converter is configured with boost and buck modes. In boost mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the lithium battery pack, and the output terminal is connected to the input terminal of the DC bus, boosting the 48V DC to 72V DC. In buck mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the DC bus, and the output terminal is connected to the input terminal of the lithium battery pack, stepping down the 72V DC to 48V DC.

[0037] The aforementioned voltage and current sensors include a photovoltaic voltage and current sensor, a diesel generator voltage and current sensor, and a battery voltage and current sensor. The photovoltaic voltage and current sensor is connected in series between the MPPT solar controller and the DC bus, the diesel generator voltage and current sensor is connected in series between the AC / DC module and the DC bus, and the battery voltage and current sensor is connected in series between the bidirectional DC-DC converter and the lithium battery pack.

[0038] The aforementioned actuators include a photovoltaic switch, a diesel generator switch, and a battery switch. The photovoltaic switch is connected in series between the MPPT solar controller and the DC bus, the diesel generator switch is connected in series between the AC / DC module and the DC bus, and the battery switch is connected in series between the bidirectional DC-DC converter and the DC bus. The control terminals of each switch are connected to the output terminal of the microcontroller.

[0039] 8. A multi-energy complementary DC power supply system for monitoring buoys using photoelectric and oil storage as described in claim 2, characterized in that the load equipment includes observation sensors, communication equipment, and low-voltage DC power loads, and the load equipment is connected to the DC bus through corresponding DC / DC converters, including 48V / 20A converters, 24V / 20A converters, 12V / 20A converters, and 5V / 20A converters.

[0040] The input terminal of the aforementioned 48V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 48V load device input terminal; the input terminal of the 24V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 24V load device input terminal; the input terminal of the 12V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 12V load device input terminal; the input terminal of the 5V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the 5V load device input terminal.

[0041] The aforementioned lithium battery pack is a 48V / 80Ah lithium battery pack. The lithium battery pack is connected to a bidirectional DC-DC converter through a battery management unit, and the output of the battery management unit is connected to the input of a microcontroller.

[0042] The aforementioned DC bus is a 72V DC bus. A voltage stabilizer is installed on the DC bus. The input terminal of the voltage stabilizer is connected to the output terminal of each power supply module, and the output terminal of the voltage stabilizer is connected to the input terminal of the load device. The control terminal of the voltage stabilizer is connected to the output terminal of the microcontroller.

[0043] In the preferred scheme, such as Figure 2 As shown, a supercapacitor energy storage module is connected in series between the output terminal of the AC / DC module of the aforementioned diesel generator system and the DC bus. The supercapacitor energy storage module includes a supercapacitor bank and an adaptive DC-DC converter. The DC-DC converter enables voltage adaptation between the supercapacitor bank and the 72V DC bus.

[0044] The diesel generator described above has a micro-start fuel control valve in its fuel circuit and a start-stop buffer clutch on its main shaft. The micro-start fuel control valve, the start-stop buffer clutch, and the supercapacitor energy storage module are all electrically connected to the microcontroller. The lithium battery pack communicates with the microcontroller controller through the battery management unit. The microcontroller controller outputs control commands based on the remaining capacity of the lithium battery pack and the real-time power output of the load to realize the micro-start fast charging control of the diesel generator.

[0045] The supercapacitor bank mentioned above is a 16V / 500F capacitor module. The adapter DC-DC converter is a boost DC-DC converter, which can boost the 16V DC output of the supercapacitor bank to 72V DC and connect it to the DC bus. The adapter DC-DC converter is equipped with a charge and discharge protection module to limit the charge and discharge current and voltage of the supercapacitor bank.

[0046] The aforementioned micro-start fuel control valve is an electronic proportional fuel control valve, which is linked to the fuel pump of the diesel generator. The microcontroller controller can adjust the fuel supply of the diesel generator through the micro-start fuel control valve, so as to achieve precise control of the generator output power within the range of 80%-100% of the rated power.

[0047] The aforementioned start-stop buffer clutch is an electromagnetic buffer clutch. Its engagement and disengagement are controlled by electrical signals from a microcontroller. When the clutch is engaged, it enables shock-free power output from the generator main shaft, and when it is disengaged, it enables the generator to stop without load.

[0048] The aforementioned supercapacitor energy storage module and lithium battery pack form a hybrid energy storage structure. Both interact with a bidirectional DC-DC converter to exchange electrical energy. The supercapacitor energy storage module is used to quickly absorb excess electrical energy when the diesel generator is running at full load, and then slowly charge the lithium battery pack through the bidirectional DC-DC converter.

[0049] The aforementioned microcontroller controller has a built-in diesel generator micro-start fast charging control program. It sets the two conditions for starting the diesel generator as the remaining capacity of the lithium battery < 40% and the real-time load power > the photovoltaic output power, and sets the remaining capacity of the lithium battery ≥ 80% or the supercapacitor bank full capacity as the diesel generator shutdown condition.

[0050] As the core control unit of the entire power supply system, the energy management module uses integrated photovoltaic voltage and current sensors, diesel generator voltage and current sensors, and battery voltage and current sensors to perform high-frequency, high-precision real-time data acquisition of the output voltage and current of the photovoltaic power generation system, the rectified voltage and current of the diesel generator system, and the charging and discharging voltage and current of the energy storage battery system. The data acquisition interval is no more than 50ms, ensuring comprehensive capture of the operating status and power output characteristics of each energy module. This acquired real-time data is synchronously transmitted to the microcontroller controller via signal transmission lines. The microcontroller controller has built-in preset energy scheduling algorithms and voltage stability control logic. First, it calculates and analyzes the photovoltaic output power, and combines it with the real-time power consumption data of the load equipment (synchronously fed back by auxiliary sensors on the DC bus side) to determine whether the light intensity meets the independent power supply requirements of the load. At the same time, by receiving data such as the remaining capacity of the lithium battery pack and the charge and discharge cycle status transmitted by the battery management unit, it evaluates the power supply support capability of the energy storage system. Based on the comprehensive analysis of the above multi-dimensional data, the microcontroller accurately outputs control commands. On the one hand, it regulates the on / off state of the photovoltaic switch, diesel generator switch and battery switch in the actuator. On the other hand, it switches the working mode (boost or buck) of the bidirectional DC-DC converter and links the adjustment function of the voltage stabilizer to ensure that the DC bus voltage is stable within the precise range of 72V±0.5V throughout the process, realizing the dynamic coordinated power supply of photovoltaic, energy storage and diesel energy. When sufficient sunlight is detected during the day (photovoltaic output power ≥ load power consumption + battery charging demand), the controller issues a command to close the photovoltaic switch, disconnect the diesel generator switch and battery switch, and control the MPPT solar controller to operate in maximum power point tracking mode. The 150V DC output from the flexible photovoltaic panel is stepped down to 72V and then input to the DC bus to directly power the load equipment. At the same time, the step-down mode of the bidirectional DC-DC converter is started to step down the excess power to 48V to charge the lithium battery pack. The voltage stabilizer finely adjusts the bus voltage in real time to offset the voltage deviation caused by load fluctuations. When insufficient daytime sunlight is detected (photovoltaic output power < load power consumption) but the remaining capacity of the lithium battery pack is ≥60%, the controller simultaneously closes the photovoltaic switch and the battery switch, and disconnects the diesel generator switch. The photovoltaic system output power is input to the bus through the MPPT controller. The insufficient part is switched to boost mode by the bidirectional DC-DC converter to boost the 48V DC power of the lithium battery pack to 72V to supplement the bus. The two work together to supply power to maintain stable operation of the load. When no sunlight is detected at night (photovoltaic output power is 0) and the remaining capacity of the lithium battery pack is ≥60%, the controller closes the battery switch, disconnects the photovoltaic switch and the diesel generator switch, and converts the power of the lithium battery pack into 72V DC input bus through the boost mode of the bidirectional DC-DC converter to independently power the load equipment. When insufficient sunlight is detected during the day or when the remaining capacity of the lithium battery pack is less than 60% at night, the controller prioritizes closing the diesel generator switch to start the diesel generator. The 220V AC power output is rectified and converted into 72V DC power by the AC / DC module and input to the bus to meet the load power supply requirements. At the same time, the controller selectively closes the photovoltaic switch (if there is sunlight) according to the real-time output status of the photovoltaic system and starts the step-down mode of the bidirectional DC-DC converter to step down the excess power on the bus side to charge the lithium battery pack until the battery management unit reports that the remaining capacity has recovered to the set value of 80%. Then the controller issues a command to disconnect the diesel generator switch and switch back to the photovoltaic-energy storage collaborative power supply or energy storage independent power supply mode, realizing efficient energy dispatch and continuous and stable power supply throughout the process. Among them, multiple 18V / 330W flexible photovoltaic panels are connected in series to form a photovoltaic module with an output voltage of 150V. This ensures that the output power of the photovoltaic power generation system meets the needs of load power supply and energy storage charging, while also adapting to the limited installation space of the buoy and improving the utilization efficiency of renewable energy. Among them, the dual-output interface design of the MPPT solar controller enables the photovoltaic system to efficiently store excess electrical energy in the lithium battery pack while directly supplying power to the load equipment, thus avoiding energy waste and enhancing the continuity of the system's power supply. Among them, the bidirectional DC-DC converter can flexibly switch between boost and buck modes, which not only solves the voltage matching problem between the 48V output of the lithium battery pack and the 72V input of the DC bus, but also realizes the bidirectional flow of electrical energy between the bus and the battery pack, giving full play to the peak shaving and valley filling role of the energy storage battery pack. Among them, the photovoltaic voltage and current sensors, diesel generator voltage and current sensors, and battery voltage and current sensors, which are set up in categories, can accurately monitor the operating parameters of each energy module, provide reliable data support for the microcontroller controller, and ensure the accuracy of energy switching and coordinated power supply. The independent control design of the photovoltaic switch, diesel generator switch and battery switch allows the energy management module to flexibly combine power supply modes according to different operating conditions, avoiding mutual interference between energy modules and improving the stability and reliability of system operation. Among them, DC / DC converters of various specifications such as 48V / 20A, 24V / 20A, 12V / 20A and 5V / 20A meet the power requirements of load equipment with different voltage levels such as observation sensors and communication equipment, and broaden the system's adaptability. Among them, the 48V / 80Ah lithium battery pack, paired with a battery management unit, not only ensures that the energy storage capacity meets the needs of the buoy for long-term offshore operation, but also monitors the battery status in real time and feeds it back to the microcontroller, effectively extending the battery life and avoiding the risk of overcharging and over-discharging. The 72V DC bus and voltage stabilizer enable standardized connection between each power supply module and the load equipment, ensuring that the bus voltage is not affected by energy switching and load fluctuations, providing a stable and reliable power supply environment for the load equipment, and ensuring the continuity of observation data acquisition and transmission.

[0051] Example 1: This embodiment illustrates specific examples of improvements to the supercapacitor and diesel power generation system in the preferred scheme. The monitoring buoy multi-energy complementary DC power supply system and device disclosed in this embodiment includes a photovoltaic power generation system, a diesel power generation system, an energy storage battery system, an energy management module, a DC bus, a supercapacitor energy storage module, and load equipment. The basic structure and connection relationship of the photovoltaic power generation system, the energy storage battery system, the energy management module, the DC bus, and the load equipment are consistent with the original technology. The core improvements are the addition of hardware structure and optimization of control strategy of the diesel power generation system, as well as the integrated application of the supercapacitor energy storage module.

[0052] Specific structure and connection relationships of each module 1. Photovoltaic power generation system: The photovoltaic module is composed of 18V / 330W flexible photovoltaic panels connected in series. After being connected in series, it outputs 150V DC power. The output terminal of the photovoltaic module is connected to the input terminal of the MPPT solar controller. The output terminal of the MPPT solar controller is connected to the input terminal of the 72V DC bus. The MPPT solar controller has two output interfaces, one of which supplies power to the DC bus, and the other of which charges the lithium battery pack through a bidirectional DC-DC converter. 2. Diesel Generator System: This system includes a diesel generator, an AC / DC module, a micro-start fuel control valve, and a start-stop buffer clutch. The diesel generator outputs 220V AC power, which is connected to the input of the AC / DC module. The AC / DC module outputs 72V DC power, and its output is connected to the input of the supercapacitor energy storage module. The micro-start fuel control valve is connected in series in the diesel generator's fuel circuit and is linked to the fuel pump. The fuel supply is controlled by a microcontroller. The start-stop buffer clutch is installed on the main shaft of the diesel generator and is an electromagnetic clutch. Its engagement and disengagement are controlled by the microcontroller to achieve shock-free start-stop. 3. Supercapacitor Energy Storage Module: Includes a 16V / 500F supercapacitor bank and a matching DC-DC converter. The matching DC-DC converter is a boost converter, with its input connected to the supercapacitor bank and its output connected to the DC bus input. Simultaneously, the matching DC-DC converter and a bidirectional DC-DC converter enable energy exchange, allowing the stored energy from the supercapacitor bank to be transferred to the lithium battery pack. The matching DC-DC converter has a built-in charge / discharge protection module, setting the supercapacitor bank's charging upper limit voltage to 16V, discharging lower limit voltage to 10V, and a maximum charging / discharging current of 20A to prevent overcharging and over-discharging of the supercapacitor. 4. Energy Storage Battery System: Includes a 48V / 80Ah lithium battery pack, a battery management unit (BMU), and a bidirectional DC-DC converter; the output of the lithium battery pack is connected to the input of the battery management unit, the output of the battery management unit is connected to the input of the bidirectional DC-DC converter, and the output of the bidirectional DC-DC converter is connected to the DC bus input; the battery management unit collects data such as the remaining capacity (SOC), charging and discharging current, voltage, and temperature of the lithium battery pack in real time, and transmits the data synchronously to the microcontroller, while also implementing overcharge, over-discharge, and over-temperature protection for the lithium battery pack; the bidirectional DC-DC converter can realize the boost conversion of 48V DC to 72V DC (lithium battery discharging) and the buck conversion of 72V DC to 48V DC (lithium battery charging); 5. Energy Management Module: This module includes voltage and current sensors, a microcontroller, and actuators. The voltage and current sensors include photovoltaic (PV) voltage and current sensors, diesel generator voltage and current sensors, battery voltage and current sensors, and supercapacitor voltage and current sensors, which monitor the output voltage and current of the PV power generation system, diesel generator system, lithium battery pack, and supercapacitor energy storage module, respectively. All sensor outputs are connected to the microcontroller's input. The actuators include PV switches, diesel generator switches, and battery switches, connected in series between each power supply module and the DC bus. The switch control terminals are connected to the microcontroller's output. The microcontroller is the core control unit of the entire system, with built-in PV priority scheduling and diesel generator micro-start fast charging control programs, enabling dynamic coordination of the power supply modules and precise energy-saving control of the diesel generator. 6. DC Bus and Load Equipment: The DC bus is 72V and equipped with a voltage stabilizer. The input terminal of the voltage stabilizer is connected to the output terminal of each power supply module, and the output terminal is connected to the input terminal of the load equipment to maintain the bus voltage stable at 72V±0.5V. The load equipment includes observation sensors, communication equipment, and low-voltage DC loads, which are connected to the DC bus through DC / DC converters with specifications of 48V / 20A, 24V / 20A, 12V / 20A, and 5V / 20A, respectively, to meet the power requirements of loads with different voltage levels.

[0053] Diesel generator micro-start fast charging control process The core execution logic of this invention is a diesel generator micro-start fast charging control strategy. This strategy is deeply integrated with the original photovoltaic priority overall energy dispatch strategy. The microcontroller controller achieves energy-saving operation of the diesel generator through multi-dimensional data acquisition and comprehensive analysis. The specific control process is as follows: 1. Real-time data acquisition: The microcontroller uses various voltage and current sensors to collect real-time data on the output power of the photovoltaic power generation system, the real-time power consumption of the load equipment, the remaining SOC of the lithium battery pack, and the voltage and remaining power of the supercapacitor energy storage module. The data acquisition interval is no more than 50ms to ensure the real-time performance and accuracy of the data. The battery management unit synchronously transmits the SOC data and charge / discharge status data of the lithium battery pack to the microcontroller, which serves as the core basis for determining the start and stop of the diesel generator. 2. Start-up condition determination: The microcontroller has built-in start-up determination logic. The diesel generator is determined to meet the start-up conditions only when the lithium battery pack SOC is less than 40% and the real-time load power is greater than the output power of the photovoltaic power generation system. Otherwise, the diesel generator is kept in the shutdown state. The dual-condition determination replaces the traditional single SOC (<60%) determination, which greatly reduces the number of invalid generator starts and reduces fuel consumption and mechanical wear from the source. 3. Shock-free generator start-up and full-load operation: When the starting conditions are met, the microcontroller first sends an electrical signal to control the start-stop buffer clutch to slowly engage, achieving shock-free power output from the generator main shaft. Then, it controls the diesel generator switch to close, starting the diesel generator. After the generator starts, the microcontroller adjusts the fuel supply through the micro-start fuel control valve, precisely controlling the generator output power to 80%-100% of the rated power at full load. At this time, the diesel generator's power generation efficiency is increased to over 90%, solving the problem of high fuel consumption in traditional low-load operation. 4. Power Distribution and Supercapacitor Fast Charging: When the diesel generator is running at full load, the 72V DC power rectified by the AC / DC module first meets the real-time power consumption requirements of the DC bus load. All excess power is sent to the supercapacitor energy storage module, where it is converted to the appropriate voltage by the matching DC-DC converter and then fast-charged to the 16V / 500F supercapacitor bank. The fast-charging characteristics of the supercapacitor bank enable rapid absorption of power and avoid waste of excess power. 5. Slow charging of lithium batteries from supercapacitors: During fast charging, the supercapacitor voltage and current sensors feed back voltage and power data to the microcontroller in real time. When the supercapacitor bank is not fully charged, the fast charging mode is maintained. When the supercapacitor bank reaches the full-capacity voltage of 16V, the microcontroller controls the adapter DC-DC converter to switch to discharge mode, and the energy stored in the supercapacitor bank is stepped down to 48V through the bidirectional DC-DC converter to slowly charge the lithium battery bank. The slow charging current is controlled within 5A to avoid the charging and discharging impact of sudden current changes on the lithium battery bank and to ensure battery life. 6. No-load shutdown of the generator: The microcontroller monitors the SOC data of the lithium battery pack and the charge data of the supercapacitor pack in real time. When the SOC of the lithium battery pack is ≥80% or the supercapacitor pack is fully charged and the SOC of the lithium battery pack no longer rises, it is determined that the shutdown conditions of the diesel generator are met. At this time, the microcontroller first cuts off the fuel supply to the diesel generator through the micro-start fuel control valve, and then sends an electrical signal to control the start-stop buffer clutch to quickly disengage, so as to realize the no-load shutdown of the generator and avoid mechanical shock during shutdown. At the same time, it controls the diesel generator switch to disconnect, completing one recharge operation of the diesel generator. 7. System restores photovoltaic-energy storage coordinated dispatch: After the diesel generator stops, the system restores the original photovoltaic priority energy dispatch strategy, with the photovoltaic power generation system supplying power alone or in coordination with the lithium battery pack. The supercapacitor energy storage module responds to the power demand of the DC bus in real time to compensate for the power, offsetting the bus voltage fluctuations caused by load changes and improving the stability of the system power supply.

[0054] Operating characteristics and protection design of key components 1. Supercapacitor Energy Storage Module: Utilizing a 16V / 500F supercapacitor bank, it features fast charging and discharging speeds, long cycle life, and excellent low-temperature performance, making it suitable for the complex environments of offshore buoys; it is compatible with the charge and discharge protection module of the DC-DC converter, which can effectively prevent overcharging and over-discharging of the supercapacitor and extend its service life; the entire supercapacitor energy storage module is encapsulated in a corrosion-resistant and waterproof enclosure with an IP67 protection rating, making it suitable for high-salt-spray marine environments; 2. Micro-start fuel control valve: It is an electronic proportional fuel control valve with an adjustment accuracy of ±1%. It can accurately adjust the fuel supply according to the electrical signal of the single-chip microcomputer controller, realize the continuous control of the diesel generator output power, and ensure that the generator always operates in the high-efficiency full-load range. 3. Start-stop buffer clutch: It is an electromagnetic buffer clutch with an engagement time adjustable to 0.5-1s and a disengagement time of <0.1s. During engagement, it achieves a smooth increase in the main shaft speed and avoids starting shock. After disengagement, the generator main shaft runs without load and there is no mechanical wear when the machine stops, which effectively extends the service life of the generator main shaft, bearings and other components. 4. Diesel generator: A miniaturized permanent magnet synchronous diesel generator is selected, with a rated power that matches the total power consumption of the buoy load. It is small in size and light in weight, making it suitable for the limited installation space of the buoy. The generator is treated with anti-corrosion and waterproof measures. The fuel tank is equipped with an anti-sloshing baffle and a liquid level sensor. The liquid level sensor is connected to a single-chip microcomputer controller, which can transmit fuel remaining data to the shore base to facilitate offshore refueling planning.

[0055] The monitoring buoy's photovoltaic-oil-storage multi-energy complementary DC power supply system and device in this embodiment, based on the original system, achieves energy-saving optimization of the diesel generator system by adding a supercapacitor energy storage module, a micro-start oil control valve, and a start-stop buffer clutch, combined with a micro-start fast charging control strategy: the number of start-stop cycles of the diesel generator is reduced by more than 60%, the full-load power generation efficiency is increased to more than 90%, and the overall fuel consumption is reduced by more than 40%; the mechanical wear of the generator is significantly reduced, the failure probability is reduced by 50%, and the service life is extended by more than 100%; the charging and discharging impact of the lithium battery pack is eliminated, and the cycle life is improved; at the same time, the addition of the supercapacitor energy storage module further improves the voltage stability of the DC bus and enhances the operational reliability of the buoy's precision loads (such as water quality monitoring sensors and wireless communication modules).

Claims

1. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys, characterized in that, This includes photovoltaic power generation systems, diesel power generation systems, energy storage battery systems, energy management modules, DC buses, and load equipment; The photovoltaic power generation system consists of a flexible photovoltaic panel and an MPPT solar controller connected in series. The output end of the flexible photovoltaic panel is connected to the input end of the MPPT solar controller, and the output end of the MPPT solar controller is connected to the input end of the DC bus. The flexible photovoltaic panel outputs a first voltage DC power, which is stepped down by the MPPT solar controller and then outputs a second voltage DC power to the DC bus. The diesel generator system includes a diesel generator and an AC / DC module. The output terminal of the diesel generator is connected to the input terminal of the AC / DC module, and the output terminal of the AC / DC module is connected to the input terminal of the DC bus. The diesel generator outputs 220V AC power, which is rectified and converted by the AC / DC module to output a second voltage DC power to the DC bus. The energy storage battery system includes a lithium battery pack and a bidirectional DC-DC converter. The output of the lithium battery pack is connected to the input of the bidirectional DC-DC converter, and the output of the bidirectional DC-DC converter is connected to the input of the DC bus. The bidirectional DC-DC converter realizes bidirectional voltage conversion between the third voltage DC output of the lithium battery pack and the second voltage DC of the DC bus. The energy management module is used to control and manage the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system; The DC bus output is connected to the load device input, enabling efficient connection between multiple power sources and the load device.

2. The photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The energy management module includes voltage and current sensors, a microcontroller controller, and an actuator. The voltage and current sensors are connected to the output terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively. The output terminal of the voltage and current sensors is connected to the input terminal of the microcontroller controller, and the output terminal of the microcontroller controller is connected to the input terminal of the actuator. The actuator is connected to the control terminals of the photovoltaic power generation system, the diesel power generation system, and the energy storage battery system, respectively.

3. The photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The multiple flexible photovoltaic panels are connected in series to form a photovoltaic module, and the output end of the photovoltaic module is connected to the input end of the MPPT solar controller.

4. The photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The MPPT solar controller has two output interfaces. One output interface is connected to the DC bus input terminal, and the other output interface is connected to the lithium battery pack input terminal through a bidirectional DC-DC converter, realizing a connection structure that simultaneously supplies power to the load device and charges the lithium battery pack.

5. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The bidirectional DC-DC converter is configured with boost mode and buck mode. In boost mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the lithium battery pack, and the output terminal is connected to the input terminal of the DC bus, boosting the third voltage DC to the second voltage DC. In buck mode, the input terminal of the bidirectional DC-DC converter is connected to the output terminal of the DC bus, and the output terminal is connected to the input terminal of the lithium battery pack, bucking the second voltage DC to the third voltage DC.

6. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 2, characterized in that, The voltage and current sensors include a photovoltaic voltage and current sensor, a diesel generator voltage and current sensor, and a battery voltage and current sensor. The photovoltaic voltage and current sensor is connected in series between the MPPT solar controller and the DC bus, the diesel generator voltage and current sensor is connected in series between the AC / DC module and the DC bus, and the battery voltage and current sensor is connected in series between the bidirectional DC-DC converter and the lithium battery pack.

7. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 2, characterized in that, The actuators include a photovoltaic switch, a diesel generator switch, and a battery switch. The photovoltaic switch is connected in series between the MPPT solar controller and the DC bus, the diesel generator switch is connected in series between the AC / DC module and the DC bus, and the battery switch is connected in series between the bidirectional DC-DC converter and the DC bus. The control terminals of each switch are connected to the output terminal of the microcontroller.

8. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 2, characterized in that, The load devices include observation sensors, communication equipment, and low-voltage DC power loads. The load devices are connected to the DC bus through corresponding DC / DC converters, including 48V / 20A converters, 24V / 20A converters, 12V / 20A converters, and 5V / 20A converters.

9. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 8, characterized in that, The input terminal of the 48V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the input terminal of the 48V load device; the input terminal of the 24V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the input terminal of the 24V load device; the input terminal of the 12V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the input terminal of the 12V load device; the input terminal of the 5V / 20A converter is connected to the DC bus output terminal, and the output terminal is connected to the input terminal of the 5V load device.

10. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The lithium battery pack is connected to a bidirectional DC-DC converter via a battery management unit, and the output of the battery management unit is connected to the input of a microcontroller.

11. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, The DC bus is equipped with a voltage stabilizer. The input terminal of the voltage stabilizer is connected to the output terminal of each power supply module, the output terminal of the voltage stabilizer is connected to the input terminal of the load device, and the control terminal of the voltage stabilizer is connected to the output terminal of the microcontroller.

12. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 1, characterized in that, A supercapacitor energy storage module is connected in series between the output terminal of the AC / DC module of the diesel generator system and the DC bus. The supercapacitor energy storage module includes a supercapacitor bank and an adaptive DC-DC converter. The DC-DC converter realizes voltage adaptation between the supercapacitor bank and the second voltage DC bus.

13. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 12, characterized in that, The diesel generator is equipped with a micro-start fuel control valve in its fuel circuit and a start-stop buffer clutch on its main shaft. The micro-start fuel control valve, the start-stop buffer clutch, and the supercapacitor energy storage module are all electrically connected to the single-chip microcomputer controller. The lithium battery pack communicates with the microcontroller controller through the battery management unit. The microcontroller controller outputs control commands based on the remaining capacity of the lithium battery pack and the real-time power output of the load to realize the micro-start fast charging control of the diesel generator.

14. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 13, characterized in that, The supercapacitor bank is a 16V / 500F capacitor module, and the adapter DC-DC converter is a boost DC-DC converter that can boost the 16V DC output from the supercapacitor bank to a second voltage DC and connect it to the DC bus. The adapter DC-DC converter is equipped with a charge and discharge protection module to limit the charge and discharge current and voltage of the supercapacitor bank.

15. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 13, characterized in that, The aforementioned micro-start fuel control valve is an electronic proportional fuel control valve, which is linked to the fuel pump of the diesel generator. The microcontroller controller can adjust the fuel supply of the diesel generator through the micro-start fuel control valve, so as to achieve precise control of the generator output power within the range of 80%-100% of the rated power.

16. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 13, characterized in that, The start-stop buffer clutch is an electromagnetic buffer clutch. Its engagement and disengagement are controlled by electrical signals from a microcontroller. When the clutch is engaged, it enables shock-free power output from the generator main shaft, and when it is disengaged, it enables the generator to stop without load.

17. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 13, characterized in that, The supercapacitor energy storage module and the lithium battery pack form a hybrid energy storage structure. Both of them interact with the bidirectional DC-DC converter to exchange electrical energy. The supercapacitor energy storage module is used to quickly absorb the excess electrical energy when the diesel generator is running at full load, and then slowly charge the lithium battery pack through the bidirectional DC-DC converter.

18. A photovoltaic-oil storage multi-energy complementary DC power supply system for monitoring buoys according to claim 13, characterized in that, The microcontroller controller has a built-in diesel generator micro-start fast charging control program. It sets the two conditions for starting the diesel generator as the remaining capacity of the lithium battery < 40% and the real-time load power > the photovoltaic output power, and sets the remaining capacity of the lithium battery ≥ 80% or the supercapacitor bank full capacity as the diesel generator shutdown condition.

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