Photovoltaic and mains complementary street lamp adaptive energy management method and system

Abstract

The present application relates to the technical field of electric energy control, in particular to a photovoltaic and mains complementary street lamp adaptive energy management method and system, the technical scheme comprising: data acquisition on the circuit to obtain system parameters; calculating the residual capacity of the lithium battery at time t according to the system parameters; judging whether the current time point belongs to the night time period, if not, determining that it is the daytime period, then implementing the daytime period energy management strategy according to the relationship among the photovoltaic panel output voltage, the photovoltaic starting charging voltage and the battery residual capacity; if yes, determining that it is the night time period, then implementing the night time period energy management strategy according to the relationship between the discharge cutoff threshold and the battery residual capacity. The present application has the advantages of significantly improved energy utilization rate, optimized lighting effect, high system stability and improved operation and maintenance efficiency, and reduced operation and maintenance cost. The present application adopts accurate lithium battery residual capacity calculation and temperature correction, combined with overcharge and overdischarge protection strategies, to avoid abnormal battery loss and extend the battery service life by more than 30%.

Description

Technical Field

[0001] This invention relates to the field of power control technology, specifically to an adaptive energy management method and system for photovoltaic and mains-powered complementary streetlights. Background Technology

[0002] Photovoltaic streetlights have become an important development direction for outdoor road lighting due to their advantages of utilizing clean solar energy, reducing municipal electricity consumption, and reducing carbon emissions. However, traditional photovoltaic streetlights rely solely on photovoltaic panels for power generation and lithium-ion batteries for energy storage, making them significantly affected by the natural environment: light intensity varies greatly with seasons, weather, and day and night. In scenarios with insufficient sunlight, such as rain, fog, or winter, lithium-ion batteries are prone to depletion, causing the streetlights to go out, making it impossible to guarantee stable lighting around the clock and resulting in poor lighting reliability.

[0003] To address the power supply deficiencies of traditional photovoltaic streetlights, existing technologies have developed photovoltaic-to-grid complementary streetlight systems, enabling basic switching between the two power supply methods. However, these systems still suffer from numerous technical challenges, failing to fully realize the value of clean energy and exhibiting insufficient overall system performance and control precision. Specifically: The energy switching and distribution logic is crude: it lacks an adaptive adjustment mechanism, fails to dynamically optimize the power supply strategy by combining real-time photovoltaic output power, lithium battery status, and actual lighting needs, lacks quantitative control over the timing of photovoltaic charging and grid power replenishment, and has low clean energy utilization, which easily leads to energy waste. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an adaptive energy management method for photovoltaic and mains-powered complementary streetlights, used for complementary control of photovoltaic and mains power to provide electricity to the streetlights. The photovoltaic and mains-powered complementary streetlight adaptive energy management method includes: S1. Acquire system parameters by collecting data from the circuit. System parameters may include the initial lithium battery voltage, cell temperature data, current time τ, and the initial remaining lithium battery charge (SOC) at system initialization, all collected by the BMS. init Lithium battery rated capacity C n (Ah) and lithium battery charging current I at time τ ch (τ) (A) (positive during charging, 0 during discharging), lithium battery discharge current I at time τ dis (τ) (A) (positive during discharge, 0 during charging), etc.

[0005] S2. Calculate the remaining battery charge (SOC) at time t based on system parameters. (t) Its value ranges from 0 to 100%.

[0006] S3. Determine whether the current time is within the nighttime period. If not, execute S4; if so, execute S5.

[0007] S4. Determine if it is daytime, then base the determination on system parameters and remaining battery SOC. (t) Relationship, implement daytime energy management strategies.

[0008] S5. Determine it as nighttime, then based on system parameters and remaining battery SOC... (t) Relationship, implement energy management strategies during nighttime hours.

[0009] Preferred: Remaining lithium battery charge at time t SOC init C represents the initial remaining capacity (%) of the lithium battery during system initialization. n Rated capacity of lithium battery (Ah); I ch (τ) represents the lithium battery charging current (A) at time τ, which is positive during charging and zero during discharging; I dis (τ) is the lithium battery discharge current (A) at time τ, which is positive during discharge and 0 during charging; KT is the temperature correction coefficient; KA is the battery aging correction coefficient.

[0010] Preferred: The temperature correction coefficient KT is dynamically adjusted according to the cell temperature: when the cell temperature is <0℃, KT=0.85; when 0℃≤cell temperature<10℃, KT=0.92; when 10℃≤cell temperature<40℃, KT=1.0; when the cell temperature is ≥40℃, KT=0.95.

[0011] Preferred: The battery aging correction factor KA has an initial value of 1.0, decreases by 0.02 every 1000 hours of operation, and decreases to a maximum of 0.8.

[0012] Preferred: Battery aging correction factor Where B is the attenuation base, with a value of 1-1.1, and T L This refers to the cumulative usage time of the lithium battery, expressed in hours. When T... L Lithium batteries that have exceeded their service life should be disposed of.

[0013] Preferred: Attenuation base B = 1.01, Preferred methods for calculating sunrise / sunset include: S31: Obtain latitude ϕ, longitude λ, date, and time zone.

[0014] S32: Calculate the solar declination δ: Where N is the number of days in a year, then calculate the solar declination δ = 0.3723 + 23.2567sinθ + 0.1149sin2θ - 0.1712sin3θ - 0.7580cosθ + 0.3656cos2θ + 0.0201cos3θ.

[0015] S33: Calculate the sunrise / sunset angle ω0, i.e., when the solar altitude angle is 0°: If |cosω0|>1: polar day (24 hours of daylight) or polar night (0 hours of daylight), then photovoltaic panels and LED lighting are not required, and are excluded here.

[0016] otherwise: in Local geographical latitude (unit: radians) S34: Calculate day length (hours) (15° / hour: Earth's rotational angular velocity) S35: Calculate local time sunrise / sunset: Sunrise (local time)

[0017] Sunset (local time) S36: Convert to Beijing time (UTC+8) jet lag

[0018] Longitude > 120° East: Positive time difference (local time is earlier than Beijing time) Longitude <120° East: Negative time difference (local time is later than Beijing time) Sunrise (Beijing Time) = Sunrise (Local Time) - Time Difference (Hours) Sunset (Beijing time) = Sunset (local time) - Time difference (hours).

[0019] Preferred: The specific steps of the daytime energy management strategy include: S4.1: Real-time acquisition of photovoltaic panel output voltage U PV and current I PV .

[0020] S4.2: If U PV ≥U PV -th and SOC (t) <100%; among which, U PV -th represents the photovoltaic startup charging voltage, which controls the photovoltaic panel to charge the lithium battery, with a charging current I. ch =I PV Ensure the charging current does not exceed the maximum charging current of the lithium battery; monitor the SOC value in real time, and when the SOC... (t) When the charge reaches 100%, the charging circuit is cut off, and the photovoltaic panel stops charging.

[0021] S4.3: If U PV ≥U PV -thbutSOC (t)=100%: This controls the photovoltaic panel to output electrical energy and feed it back to the mains power through the AC / DC drive power supply (optional, requires compatibility with grid standards), or stops the photovoltaic panel from outputting electrical energy (to avoid overcharging).

[0022] S4.4: U PV PV -th (insufficient light): The intelligent charging and discharging module is in a static state and does not start charging; the lithium battery maintains its current SOC value.

[0023] Preferred steps for nighttime energy management strategies include: S5.1: When time reaches T start Initiate the lighting procedure and reach T. end Turn off the lights program; S5.2: Determine the remaining SOC of the lithium battery at time t. (t) Is it greater than or equal to SOC? dis -th, if yes, execute S5.3; otherwise, execute S5.4; S5.3: Controls lithium battery discharge, outputting current I LED Adjust according to the current lighting ratio for the current time period; Real-time lighting current calculation I LED =I LED -max×R light , where I LED -max=2A (maximum output current), R light The current lighting ratio (0~1); real-time monitoring of SOC. (t) Value and cell temperature, if SOC (t) Reduced to SOC dis -If the temperature of the battery cell exceeds 45℃, the power supply mode will be switched.

[0024] S5.4: AC power supply mode; stops lithium battery discharge, starts AC / DC drive power supply, and supplies power to LED light source by AC power, output current I LED Adjust according to the current lighting ratio for the current time period.

[0025] Preferably: the discharge cutoff threshold Where SOC' is the battery's basic threshold value. The average overtemperature difference during the stage, T' is the unit temperature difference adjustment amount, and L is the average overtemperature difference during the stage. T R represents the duration of the phased lighting dimension, R represents the standard lighting ratio, and a represents the dimension adjustment base.

[0026] Preferred: The stage average over-temperature difference, when the average temperature exceeds the range of [10, 30]. =0, when the average temperature exceeds [10,30], it is above 30 degrees. ​When the average temperature is above or below 10 degrees Celsius, .

[0027] Preferred: The lighting period is divided into three time periods: Peak hours (e.g., 18:00~22:00): Lighting ratio R light =100% (output current 2A, full brightness); Off-peak hours (e.g., 22:00~4:00): Lighting ratio R light =60% (output current 1.2A, medium brightness); Off-peak hours (e.g., 4:00~6:00): Lighting ratio R light =80% (output current 1.6A, higher brightness).

[0028] Preferred: Calculate the residual current output from the mains power: I surplus =I AC -output-I LED , where I AC -output is the maximum output current of the AC / DC drive power supply (2A). If I surplus =0 (mains power output is fully utilized), no changes will be made; If I surplus >0 (Main power output not fully utilized): Controls the remaining current to charge the lithium battery, charging current I ch =I surplus Until SOC is upgraded to SOC dis -th+10% (to avoid frequent switching) or mains power supply ends; If I AC -output≥I LED +I ch -max (Main power output meets lighting + maximum charging requirements): Press I LED (Time Period Ratio) and I ch -max (maximum charging current of lithium battery) allocates current; I AC -output LED +I ch -max: Prioritize ensuring lighting current I LED The remaining current is used entirely for charging, and the output current of the AC / DC drive power supply is adjusted to match the current total demand.

[0029] This invention also proposes a photovoltaic and mains-powered complementary adaptive energy management system for streetlights, used to control the current transmission between photovoltaic panels, mains power, lithium batteries, and LED light sources, including: The data collection module is used to collect circuit operation data. ​

[0030] The information transmission module is used to transmit circuit operation data and signal commands.

[0031] The time period determination module is used to determine whether the current time point belongs to the nighttime period. If it does, it is the nighttime period (lights-on period); otherwise, it is the daytime period. Specifically, it determines whether the current time point is within the nighttime period.

[0032] The intelligent charging and discharging module is used to execute corresponding energy management strategies according to specific time periods and output corresponding switching commands.

[0033] The power supply mode switching module is used to receive switching commands and switch the power supply mode according to the switching commands.

[0034] The adaptive adjustment and fault handling module is used for real-time adjustment and fault handling based on the detection data.

[0035] The technical effects and advantages of this invention are as follows: Significantly improved energy efficiency: Through the adaptive complementarity of photovoltaic and grid power, the utilization of clean energy is maximized and grid power consumption is reduced; the surplus energy during grid power supply is recovered and recharged, further reducing energy consumption; Extended lifespan of energy storage batteries: By employing precise calculation of remaining lithium battery capacity and temperature correction, combined with overcharge and over-discharge protection strategies, abnormal battery damage is avoided, and the battery lifespan is expected to be extended by more than 30%. Optimized lighting effect: The brightness of the lights is dynamically adjusted according to the time of day, which not only meets the lighting needs of different times of day, but also reduces ineffective energy consumption, saving 40% to 60% energy compared to traditional constant brightness street lights; High system stability: Clear switching conditions, quantified control parameters, and real-time status monitoring avoid frequent switching and escalation of faults, ensuring stable operation of streetlights around the clock; Improved operational efficiency: Remote monitoring, parameter adjustment, and fault early warning functions reduce on-site operational workload and lower operational costs. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the adaptive energy management method for photovoltaic and grid-connected streetlights proposed in this invention.

[0037] Figure 2 This is a flowchart illustrating the specific steps of the daytime energy management strategy in the photovoltaic and grid-connected adaptive energy management method for streetlights proposed in this invention.

[0038] Figure 3 This is a flowchart illustrating the specific steps of the nighttime energy management strategy in the photovoltaic and grid-connected adaptive energy management method for streetlights proposed in this invention.

[0039] Figure 4 The output current I in the adaptive energy management method for photovoltaic and grid-connected streetlights proposed in this invention is... LED A flowchart illustrating the method for adjusting the lighting ratio based on the current time period.

[0040] Figure 5 This is a structural block diagram of an adaptive energy management system for photovoltaic and grid-connected streetlights proposed in this invention. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the invention, and should not be construed as limiting the invention. Rather, embodiments of the invention include all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0042] Example 1 refer to Figure 1 This embodiment proposes an adaptive energy management method for photovoltaic and grid-connected complementary streetlights, used to perform complementary control of photovoltaic and grid power to provide electricity to the streetlights. The adaptive energy management method for photovoltaic and grid-connected complementary streetlights includes: After the system is powered on, it needs to perform a self-test on the entire circuit to check the connection status and communication links of each component (photovoltaic panel, AC / DC drive power supply, lithium battery, LED light source) to ensure that the circuit system can operate normally after startup. Then, the system is configured using initial parameters, which can be system-provided or default parameters. If system-provided, the initial parameters can be received and configured via the 4G communication module. The system's default parameters can be: discharge cutoff SOC threshold (SOC). dis -th=20%; Photovoltaic startup charging voltage U PV -th=12V; Lighting time: 18:00 (T start )~6:00 (T) end (Peak / Off-peak / Row periods); Lighting ratio R for each period light Of course, this is just a simple example, and other specific situations will not be elaborated here.

[0043] S1. Acquire system parameters by collecting data from the circuit. System parameters may include the initial lithium battery voltage, cell temperature data, current time τ, and the initial remaining lithium battery charge (SOC) at system initialization, all collected by the BMS. init Lithium battery rated capacity C n (Ah) and lithium battery charging current I at time τ ch(τ) (A) (positive during charging, 0 during discharging), lithium battery discharge current I at time τ dis (τ) (A) (positive when discharging, 0 when charging), etc., and uploaded to the storage module for storage.

[0044] S2. Calculate the remaining lithium battery charge SOC(t) at time t based on the system parameters. The value of SOC(t) ranges from 0 to 100%. SOC init The initial remaining lithium battery charge (%) during system initialization can be calibrated by the BMS; C n Rated capacity of lithium battery (Ah); I ch (τ) represents the lithium battery charging current (A) at time τ, which is positive during charging and zero during discharging; I dis (τ) represents the lithium battery discharge current (A) at time τ, which is positive during discharge and zero during charging; KT is the temperature correction coefficient, dynamically adjusted according to the cell temperature: KT=1.0 when the cell temperature is 25℃ (standard temperature); KT=0.85 when the cell temperature < 0℃; KT=0.92 when 0℃≤cell temperature<10℃; KT=1.0 when 10℃≤cell temperature<40℃; KT=0.95 when the cell temperature ≥ 40℃; KA: battery aging correction coefficient, initially 1.0, decreasing by 0.02 every 1000 hours of operation (maximum decrease to 0.8). The battery aging correction coefficient KA can also be calculated. Where B is the attenuation base, with a value of 1-1.1, and preferably B=1.01; T L This refers to the cumulative usage time of the lithium battery, expressed in hours. When T... LLithium batteries exceeding their service life are scrapped. This method characterizes battery aging, conforming to the aging pattern of batteries initially stabilizing and then accelerating, resulting in more accurate calculations compared to fixed value settings. This method employs a fusion calculation model of "ampere-hour integration + dual dynamic correction," overcoming the limitations of traditional single algorithms. It abandons existing single-method SOC calculation methods such as ampere-hour integration and open-circuit voltage methods, and for the first time quantitatively integrates ampere-hour integration (basic calculation), temperature dynamic correction (environmental adaptation), and battery aging dynamic correction (full lifecycle adaptation) to construct a precise SOC calculation model suitable for outdoor photovoltaic streetlights. Instead of fuzzy design for temperature correction, it divides KT into 5 precisely quantified intervals based on the actual operating temperature range of photovoltaic streetlight lithium batteries (-20℃~60℃). The coefficient value of each interval is calibrated based on experimental data of lithium battery charge and discharge efficiency (e.g., at low temperatures <0℃, charge and discharge efficiency drops to 85%, so KT=0.85; at high temperatures ≥40℃, efficiency drops to 95%, so KT=0.95), rather than a simple linear correction. This quantitative design aligns with the temperature variation patterns of outdoor streetlights, avoiding secondary errors caused by fuzzy corrections. It achieves engineered and precise temperature correction, allowing direct embedding into the MCU program of the intelligent charging and discharging module without complex calculations. While existing technologies consider the impact of battery aging on SOC, they are mostly fuzzy corrections without a clear attenuation pattern, not linked to the actual battery operating time. This design quantitatively binds the KA attenuation pattern to the actual operating time of the lithium battery, setting a lifespan rule of "0.02 attenuation per 1000 hours of operation, with a maximum attenuation of 0.8." This rule is based on outdoor operating life experiments of photovoltaic streetlight lithium batteries (the typical outdoor operating life of lithium batteries is approximately 10,000 hours, with 80% capacity attenuation as the scrap threshold), achieving a precise quantitative correlation between battery aging and SOC calculation. Simultaneously, the maximum attenuation limit of 0.8 not only meets the lithium battery industry's scrapping standards but also provides maintenance personnel with a clear signal for battery replacement, deeply integrating SOC calculation with operation and maintenance management, breaking through the traditional single function of SOC calculation focusing only on "power monitoring." Both correction coefficients in this formula are adjusted in real time, automatically, and without manual intervention: KT is automatically matched to the corresponding interval coefficient based on the cell temperature collected in real time by the BMS, and KA is automatically calculated by the intelligent charging and discharging module based on the cumulative battery operating time. The calculation process is fully embedded in the system's real-time data acquisition and control flow, requiring no manual calibration or parameter adjustment. This innovative design is highly consistent with the core concept of "adaptive energy management" of this invention, making SOC calculation the dynamic data core of the system's adaptive energy management, rather than static parameter monitoring. This ensures the adaptive switching of strategies such as photovoltaic charging, lithium battery power supply, and mains power supplementation, realizing the full-process collaboration of "precise SOC calculation - precise battery control - adaptive energy allocation".The intelligent charging and discharging module of photovoltaic streetlights is a miniaturized embedded controller. However, the limited computing power of the MCU (Microcontroller Unit) cannot support complex SOC (System-on-Chips) computational algorithms such as machine learning and Kalman filtering (while these algorithms offer high accuracy, they require powerful hardware and are susceptible to noise from outdoor data acquisition). To ensure computational accuracy, the fusion computational model is designed to be lightweight and engineered. All calculations are basic integration and multiplication operations, with correction coefficients set to fixed quantization values. This allows for direct implementation through a simple MCU program, eliminating the need for increased hardware costs. This design perfectly complements the miniaturized and low-power hardware characteristics of photovoltaic streetlight controllers, making it feasible for large-scale engineering applications.

[0045] S3. Determine whether the current time period is nighttime. If not, proceed to S4; otherwise, proceed to S5. The work period can be determined by the lighting period, which can be set through initial parameter configuration, such as 18:00~6:00 (peak / off-peak / low-peak period division). The specific time can be set according to the local sunrise and sunset times.

[0046] It can also be obtained through calculation, as follows: S31: Obtain latitude ϕ (positive for North latitude, negative for South latitude), longitude λ (positive for East longitude, negative for West longitude), date: yearly day N (January 1st = 1, February 1st = 32, ...), and time zone light.

[0047] S32: Calculate the solar declination δ: Where N is the number of days in a year, then calculate the solar declination δ = 0.3723 + 23.2567sinθ + 0.1149sin2θ - 0.1712sin3θ - 0.7580cosθ + 0.3656cos2θ + 0.0201cos3θ.

[0048] S33: Calculate the sunrise / sunset angle ω0, i.e., when the solar altitude angle is 0°: If |cosω0|>1: polar day (24 hours of daylight) or polar night (0 hours of daylight), then photovoltaic panels and LED lighting are not required, and are excluded here.

[0049] otherwise: in Local geographical latitude (unit: radians) S34: Calculate day length (hours) (15° / hour: Earth's rotational angular velocity) S35: Calculate local time sunrise / sunset: Sunrise (local time)

[0050] Sunset (local time) S36: Convert to Beijing time (UTC+8) jet lag

[0051] Longitude > 120° East: Positive time difference (local time is earlier than Beijing time) Longitude <120° East: Negative time difference (local time is later than Beijing time) Sunrise (Beijing Time) = Sunrise (Local Time) - Time Difference (Hours) Sunset (Beijing Time) = Sunset (Local Time) - Time Difference (Hours) This method is suitable for precise calculations, and can also be obtained from local meteorological bureau information. However, local meteorological bureau information cannot be adjusted according to specific and precise latitude and longitude, and there is a certain degree of error.

[0052] S4. Determine if it is a daytime period (not a lighting period), then determine the photovoltaic panel output voltage, photovoltaic start-up charging voltage, and remaining battery SOC. (t) Relationship, implement daytime energy management strategies. (Reference) Figure 2 The specific steps are as follows: S4.1: Real-time acquisition of photovoltaic panel output voltage and current U PV and I PV .

[0053] S4.2: If U PV ≥U PV -th and SOC (t) <100%; among which, U PV -th represents the photovoltaic startup charging voltage, typically 12V, U PV ≥U PV -th indicates sufficient light. SOC (t) Let I be the remaining charge (%) of the lithium battery at time t. Then, control the photovoltaic panel to charge the lithium battery, with a charging current I. ch =I PV Ensure the charging current does not exceed the maximum charging current of the lithium battery; monitor the SOC value in real time, and when the SOC... (t) When the charge reaches 100%, the charging circuit is cut off, and the photovoltaic panel stops charging.

[0054] S4.3: If U PV ≥U PV -thbutSOC (t) =100%: This controls the photovoltaic panel to output electrical energy and feed it back to the mains power through the AC / DC drive power supply (optional, requires compatibility with grid standards), or stops the photovoltaic panel from outputting electrical energy (to avoid overcharging).

[0055] S4.4: U PV PV ​-th (insufficient light): The intelligent charging and discharging module is in a static state and does not start charging; the lithium battery maintains its current SOC value.

[0056] S5. Determine if it is a nighttime period (lighting period), and then determine the discharge cutoff threshold SOC. dis -th and remaining battery SOC (t) Relationship, implement nighttime energy management strategies. (Reference) Figure 3 The specific steps are as follows: S5.1: Light activation and power supply source judgment when time reaches T start Initiate the lighting procedure and reach T. end Turn off the lights program; S5.2: Determine the remaining SOC of the lithium battery at time t. (t) Is it greater than or equal to SOC? dis -th (Discharge cutoff threshold SOC) dis -th can generally be 20%); if so, execute S5.3; otherwise, execute S5.4. S5.3: Controls lithium battery discharge, outputting current I LED (Implementing lighting current) Adjusted according to the lighting ratio for the current time period; Lighting time settings: Supports remote configuration, with three default time periods, which can be adjusted through the smart lighting management platform. Peak hours (e.g., 18:00~22:00): Lighting ratio R light =100% (output current 2A, full brightness); Off-peak hours (e.g., 22:00~4:00): Lighting ratio R light =60% (output current 1.2A, medium brightness); Off-peak hours (e.g., 4:00~6:00): Lighting ratio R light =80% (output current 1.6A, higher brightness). Of course, this is just a simple example and may not be universally applicable.

[0057] Real-time lighting current calculation I LED =I LED -max×R light , where I LED -max=2A (maximum output current), R light The current lighting ratio (0~1); real-time monitoring of SOC. (t) Value and cell temperature, if SOC (t) Reduced to SOC dis -If the battery temperature exceeds 45°C, the power supply mode switch is triggered. The discharge cutoff threshold (SOC) is mentioned above. dis-th can also be obtained directly through calculation, specifically: SOC' is the battery's basic threshold. For example, the basic threshold for ternary lithium batteries is about 15%, and the basic threshold for lithium iron phosphate batteries is about 20%. Of course, other values ​​are not excluded. The stage average over-temperature difference is defined. The cell operating temperature can be [0, 40]. Temperatures exceeding this range require adjustment. The stage average over-temperature difference evaluation range can be [10, 30], although other values ​​are not excluded. Details are omitted here. If the average temperature is within the [10, 30] range, no calculation is performed. If the average temperature exceeds [10, 30] and is above 30 degrees Celsius, then… When the average temperature is above or below 10 degrees Celsius, The specific calculation process will not be detailed here. T' is the unit temperature difference adjustment, and its value can be 10, although other values ​​are not excluded; details will not be elaborated here. L T The duration of the phased lighting dimension can be the average lighting duration of streetlights over a week, half a month, or a month. This can be obtained from historical data and determined based on actual conditions, which will not be elaborated here. R is the standard lighting ratio, which can be 1. L' is the standard lighting dimension duration, which can be 10, although other values ​​are not excluded, which will not be elaborated here. a is the dimension adjustment base, which can be 3-5, and will not be elaborated here. The discharge cutoff threshold SOC obtained through this method... dis -th can perform multi-dimensional calculations based on specific circumstances, thereby maximizing dynamic control and avoiding energy waste or battery over-discharge caused by fixed thresholds. This increases calculation accuracy and battery protection capabilities. Furthermore, the calculation method conforms to the variation patterns of threshold parameters.

[0058] S5.4: AC power supply mode; stops lithium battery discharge, starts AC / DC drive power supply, and supplies power to LED light source from AC power. (Refer to...) Figure 4 Output current I LED Adjust according to the current lighting ratio: Calculate the residual current output from the mains power supply: I surplus =I AC -output-I LED , where I AC -output is the maximum output current of the AC / DC drive power supply (2A). If I surplus =0 (mains power output is fully utilized), no changes will be made; If I surplus >0 (Main power output not fully utilized): Controls the remaining current to charge the lithium battery, charging current I ch =I surplusUntil SOC is upgraded to SOC dis -th+10% (to avoid frequent switching) or mains power supply ends; If I AC -output≥I LED +I ch -max (Mains power output meets lighting + maximum charging needs): based on ILED (time period ratio) and I ch -max (maximum charging current of lithium battery) allocates current; If I AC -output LED +I ch -max: Prioritize ensuring lighting current I LED The remaining current is used entirely for charging. The intelligent charging and discharging module adjusts the output current of the AC / DC drive power supply via PWM signals to match the current total demand (mains output meets lighting requirements). LED +Charging demand current I ch ).

[0059] Example 2 refer to Figure 5 A photovoltaic (PV) and mains-powered complementary adaptive energy management system for streetlights is disclosed. This system controls the current transmission between PV panels, mains power, lithium batteries, and LED light sources. The PV panels convert natural light energy into direct current (DC) to provide clean energy input to the system. The output voltage range is 0-18V, and the output current range is 0-5.5A. The DC output interface is matched to the PV input terminal of the intelligent charging / discharging module. The lithium batteries store the electrical energy generated by the PV panels and power the LED light sources when needed. They are compatible with a 48V rated voltage and support the charging / discharging control of the intelligent charging / discharging module. They also include built-in voltage and cell temperature sensors. The LED light sources convert electrical energy into light energy for road lighting and are compatible with a 48V rated supply voltage. They support 0-2A current adjustment (corresponding to brightness adjustment). The data collection module is used to collect circuit operation data, which can include basic data and real-time data. Real-time data is data that changes constantly and is typically collected every 5 minutes, such as the current time t, temperature, light intensity, and photovoltaic panel output voltage U. PV and current I PV At time τ, the lithium battery charging current I ch (τ) (A), positive during charging, 0 during discharging; lithium battery discharge current I at time τ. dis (τ)(A). Specifically, data can be acquired through a BMS to obtain the SOC value and cell temperature in real time. The basic data consists of data that does not change frequently, such as the initial remaining SOC of the lithium battery during initialization. init Lithium battery rated capacity C n ​(Ah), discharge cutoff SOC threshold (SOC) dis -th=20%; Photovoltaic startup charging voltage U PV -th=12V; Lighting hours: 18:00~6:00 (peak / off-peak / low-peak periods); Lighting ratio for each period R light The specifics will not be elaborated here.

[0060] The information transmission module is used to transmit circuit operation data and signal commands. The information transmission module can be wireless or wired, and can use a 4G communication module. It uploads data every 15 minutes, including: SOC value, cell temperature, photovoltaic output power, mains power consumption, LED operating current, and status of each module.

[0061] The time period determination module is used to determine whether the current time point belongs to the nighttime period. If it does, it is the nighttime period (lights-on period); otherwise, it is the daytime period. Specifically, it determines whether the current time point is within the nighttime period.

[0062] The intelligent charging and discharging module is used to execute corresponding energy management strategies based on specific time periods and output corresponding switching commands. Nighttime energy management strategies are implemented during nighttime hours, and daytime energy management strategies are implemented during daytime hours.

[0063] The power supply mode switching module is used to receive switching commands and switch the power supply mode according to the switching commands. The power supply mode switching module may include an AC / DC drive power supply and a lithium battery charging and discharging module. The AC / DC drive power supply is used to drive the mains power supply, and the lithium battery charging and discharging module is used to control the charging and discharging of the lithium battery.

[0064] The adaptive adjustment and fault handling module is used for real-time adjustment and fault handling based on detection data. Real-time adjustment: The data collection module collects photovoltaic output, SOC value, and mains power status data every 5 minutes, dynamically adjusting the charging / discharging current and lighting current to ensure the system operates in optimal condition. Fault handling: If the BMS detects an abnormal lithium battery voltage (>55V or <40V) or cell temperature >50℃, the intelligent charging / discharging module immediately cuts off the lithium battery circuit, switches to mains power supply, and sends a fault alarm via the information transmission module; if the photovoltaic panel output is short-circuited, the photovoltaic input circuit is cut off, fault information is recorded, and an alarm is triggered.

[0065] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0066] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for adaptive energy management of photovoltaic and grid-connected complementary streetlights, characterized in that, The adaptive energy management method for photovoltaic and grid-connected complementary streetlights includes: S1. Acquire system parameters by collecting data from the circuit; S2. Calculate the remaining battery charge (SOC) at time t based on system parameters. (t) ; S3. Determine whether the current time is within the nighttime period. If not, execute S4; if yes, execute S5. S4. Determined to be daytime, based on system parameters and remaining battery SOC. (t) Relationship, implement daytime energy management strategies; S5. Determined to be nighttime, based on system parameters and remaining battery SOC. (t) Relationship, implement energy management strategies during nighttime hours.

2. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 1, characterized in that, Remaining lithium battery charge at time t SOC init C represents the initial remaining charge of the lithium battery during system initialization. n Rated capacity of lithium battery; I ch (τ) represents the lithium battery charging current at time τ, which is positive during charging and zero during discharging; I dis (τ) represents the lithium battery discharge current at time τ, which is positive during discharge and zero during charging; KT is the temperature correction coefficient; KA is the battery aging correction coefficient.

3. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 2, characterized in that, The temperature correction factor KT is dynamically adjusted according to the cell temperature: when the cell temperature is <0℃, KT=0.85; when 0℃≤cell temperature<10℃, KT=0.92; when 10℃≤cell temperature<40℃, KT=1.0; when the cell temperature is ≥40℃, KT=0.

95.

4. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 2, characterized in that, The battery aging correction factor KA has an initial value of 1.0, which decreases by 0.02 every 1000 hours of operation, with a maximum decrease to 0.

8.

5. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 1, characterized in that, The specific steps of daytime energy management strategies include: S4.1: Real-time acquisition of photovoltaic panel output voltage U PV and output current I PV ; S4.2: If U PV ≥U PV -th and SOC (t) <100%; among which, U PV -th represents the photovoltaic startup charging voltage, which controls the photovoltaic panel to charge the lithium battery, with a charging current I. ch =I PV Ensure the charging current does not exceed the maximum charging current of the lithium battery; monitor the SOC value in real time, and when the SOC... (t) When the charge reaches 100%, the charging circuit is cut off, and the photovoltaic panel stops charging. S4.3: If U PV ≥U PV -thbutSOC (t) =100%: This controls the photovoltaic panel to output electrical energy and feed it back to the mains power through the AC / DC drive power supply, or stops the photovoltaic panel from outputting electrical energy. S4.4: U PV PV -th indicates that the intelligent charging and discharging module is in a static state and does not start charging, so the lithium battery maintains its current SOC value.​ 6. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 1, characterized in that, The specific steps of the nighttime energy management strategy include: S5.1: When time reaches T start Initiate the lighting procedure and reach T. end Turn off the light-on program; S5.2: Determine the remaining SOC of the lithium battery at time t. (t) Is it greater than or equal to SOC? dis -th, if yes, execute S5.3; otherwise, execute S5.4; S5.3: Controls lithium battery discharge, outputting current I LED Adjust according to the current lighting ratio for the current time period; S5.4: AC power supply mode; stops lithium battery discharge, starts AC / DC drive power supply, and supplies power to LED light source by AC power, output current I LED Adjust according to the current lighting ratio for the current time period.

7. The adaptive energy management method for photovoltaic and grid-connected complementary streetlights according to claim 6, characterized in that, Real-time lighting current calculation I LED =I LED -max×R light , where I LED -max=2A,R light The current lighting ratio; real-time monitoring of SOC. (t) Value and cell temperature, if SOC (t) Reduced to SOC dis -If the temperature of the battery cell exceeds 45℃, the power supply mode will be switched.

8. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 1, characterized in that, Mains power supply mode, output current I LED The method for adjusting the lighting ratio based on the current time period includes: calculating the residual current output from the mains power supply: I surplus =I AC -output-I LED , where I AC -output is the maximum output current of the AC / DC drive power supply; If I surplus =0, no change; If I surplus >0: Controls the residual current to charge the lithium battery, charging current I ch =I surplus Until SOC is upgraded to SOC dis -th+10% or the mains power supply ends; If I AC -output≥I LED +I ch -max: Press I LED and I ch -Max allocation current; I AC -output LED +I ch -max: Prioritize ensuring lighting current I LED The remaining current is used entirely for charging, and the output current of the AC / DC drive power supply is adjusted to match the current total demand.​ 9. The adaptive energy management method for photovoltaic and grid-connected streetlights according to claim 7, characterized in that, The lighting period is divided into three time periods: Peak hours: Lighting ratio R light =100%; Off-peak hours: Lighting ratio R light =60%; Off-peak hours: Lighting ratio R light =80%.

10. A photovoltaic and grid-connected adaptive energy management system for streetlights, characterized in that, include: The data acquisition module is used to collect circuit operation data; The information transmission module is used to transmit circuit operation data and signal commands; The time period determination module is used to determine whether the current time point belongs to the nighttime period. If it does, it is the nighttime period; otherwise, it is the daytime period. The intelligent charging and discharging module is used to execute corresponding energy management strategies according to specific time periods and output corresponding switching commands; A power supply mode switching module is used to receive switching commands and switch the power supply mode according to the switching commands; An adaptive adjustment and fault handling module is used for real-time adjustment and fault handling based on detection data.

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