An adaptive polarity pid healing power supply for optical storage systems

Abstract

The application provides a self-adaptive polarity PID repair power supply for a light storage system in the field of photovoltaic power generation and energy storage technology, which comprises a wide voltage input flyback conversion module for converting wide-range fluctuating voltage of a DC bus into stable DC voltage; a polarity switching module, an input end of which is connected with an output end of the wide voltage input flyback conversion module; the polarity switching module is provided with a controlled switching switch element; an intelligent control module, which is electrically connected with the polarity switching module, is used for outputting a control signal according to an input repair mode instruction, so as to drive the switch element to switch states; a current-limiting output module, which is connected in series in an output loop of the polarity switching module; the polarity switching module is configured to have a first working mode and a second working mode in response to the control signal of the intelligent control module. The application has the advantages that the adaptability, compatibility and synergy of the PID repair power supply are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power generation and energy storage technology, and in particular to an adaptive polarity PID repair power supply for photovoltaic-energy storage systems. Background Technology

[0002] While photovoltaic-energy storage integrated systems improve energy utilization efficiency, their photovoltaic modules also face the significant threat of potential-induced degradation (PID). The PID effect causes a severe drop in module power output, directly impacting system power generation efficiency and economic returns. Currently, PID repair technologies for traditional grid-connected photovoltaic systems are relatively mature, primarily involving applying a specific polarity DC high voltage between the module and ground using external repair devices to neutralize ion migration and restore module performance. However, when these solutions are applied to the complex and variable operating conditions of photovoltaic-energy storage systems, the following key limitations exist: 1. Fixed repair polarity, incompatible with multiple module types: Conventional repair devices generally only provide a single polarity (positive or negative voltage) output. However, photovoltaic and energy storage systems may use a mix of P-type and N-type photovoltaic modules, which require repair voltages with opposite polarities (P-type often requires negative voltage, and N-type often requires positive voltage). If both types of modules need to be supported simultaneously, an additional repair device must be added, leading to increased costs, structural complexity, and operational difficulties.

[0003] 2. Insufficient adaptability to wide-range fluctuations in DC bus voltage: The DC bus voltage of a photovoltaic-storage system fluctuates significantly with photovoltaic output and battery status—supported by the photovoltaic strings during periods of good sunlight, but supplied by the batteries at night or in the absence of sunlight, resulting in significant voltage level differences. Most traditional repair devices have limited operating voltage ranges. When the bus voltage drops below its operating threshold, the device will shut down or fail to start, causing PID repair to be interrupted during critical periods, making it difficult to achieve continuous 24 / 7 protection.

[0004] 3. High dependence on power supply, functional failure under off-grid conditions: Some existing solutions obtain operating power from the AC grid or independent auxiliary power sources. When the photovoltaic-storage system is in off-grid operation mode, such repair devices often fail completely due to the loss of stable power supply, resulting in the system lacking PID repair capability in this critical operating mode, posing a long-term reliability hazard.

[0005] 4. Low level of intelligence and lack of system coordination: Existing repair devices are mostly isolated "dumb terminals" that cannot interact with the upper-level energy management system of the photovoltaic-storage system for information exchange and strategy coordination. Their operating parameters cannot be dynamically adjusted according to the actual system status (such as grid-connected / off-grid, charging / discharging mode, and component health status), which may not only affect the repair effect but also cause conflicts with the system control strategy and even lead to unnecessary additional energy consumption.

[0006] Therefore, how to provide an adaptive polarity PID repair power supply for photovoltaic energy storage systems, and improve the adaptability, compatibility and synergy of the PID repair power supply, has become an urgent technical problem to be solved. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide an adaptive polarity PID repair power supply for photovoltaic energy storage systems, thereby improving the adaptability, compatibility and synergy of the PID repair power supply.

[0008] This invention is implemented as follows: an adaptive polarity PID repair power supply for a photovoltaic energy storage system, comprising: A wide-voltage input flyback converter module is used to convert a wide range of fluctuating DC bus voltage into a stable DC voltage; A polarity switching module is provided, with its input terminal connected to the output terminal of the wide voltage input flyback converter module; the polarity switching module is equipped with a controlled switching switching element. An intelligent control module, electrically connected to the polarity switching module, is used to output a control signal according to the input repair mode command to drive the switching element to switch states. A current-limiting output module is connected in series in the output circuit of the polarity switching module; The polarity switching module is configured to respond to the control signal from the intelligent control module, and has a first operating mode and a second operating mode: In the first working mode, the current limiting output module outputs a repair voltage that is negative relative to ground, which is suitable for PID repair of P-type photovoltaic modules; In the second operating mode, the current limiting output module outputs a repair voltage that is positive relative to ground, which is suitable for PID repair of N-type photovoltaic modules.

[0009] Furthermore, the wide voltage input flyback converter module employs a flyback switching power supply controller IC with integrated MOSFETs and includes a high-frequency transformer that provides electrical isolation.

[0010] Furthermore, the wide voltage input flyback converter module has an input voltage range of 300-1000VDC, an output DC voltage of 500VDC, and a rated output power of 5W to 15W.

[0011] Furthermore, the switching element is a single-pole double-throw high-voltage relay; The common terminal of the single-pole double-throw high-voltage relay is connected to the positive output terminal of the wide voltage input flyback converter module; The normally closed contact of the single-pole double-throw high-voltage relay forms the output path of the first working mode, and the normally open contact forms the output path of the second working mode. The coil of the single-pole double-throw high-voltage relay is driven by the control signal of the intelligent control module.

[0012] Furthermore, when the intelligent control module issues a control signal, it first controls the wide voltage input flyback converter module to stop outputting, and then controls the wide voltage input flyback converter module to resume outputting after the switching element completes the state switching.

[0013] Furthermore, the intelligent control module is a microcontroller, which acquires the repair mode command through at least one of the following methods: Receive signals from local hardware settings components; Receive communication commands from the remote energy management system; Automatic identification and judgment are based on the detection of electrical parameters of photovoltaic modules.

[0014] Furthermore, the current-limiting output module includes at least one high-resistance power resistor with a resistance range of 25kΩ to 1MΩ, used to limit the maximum repair current to below 20mA.

[0015] The advantages of this invention are: 1. By adopting a wide-voltage input flyback converter module that draws power directly from the DC bus of the photovoltaic-storage system, the system effectively adapts to large-scale fluctuations in bus voltage and ensures continuous and stable operation under off-grid conditions, thereby significantly improving the adaptability of the power supply. Through a polarity switching module driven by an intelligent control module, the polarity of the output repair voltage is flexibly controllable, enabling it to automatically adapt to different types of photovoltaic modules, such as P-type and N-type, greatly enhancing the power supply's compatibility. Simultaneously, the intelligent control module can receive local settings, remote system commands, or dynamically adjust the operating mode based on automatic detection results, enabling information interaction and strategy coordination between the repair power supply and the upper-level energy management system. This ultimately achieves a leap in intelligence, improves overall synergy, and significantly enhances the adaptability, compatibility, and synergy of the PID repair power supply.

[0016] 2. By integrating a polarity switching module and an intelligent control module, the adaptive switching of the power supply output polarity is achieved. It can output negative voltage to repair P-type photovoltaic modules in the first working mode and output positive voltage to repair N-type photovoltaic modules in the second working mode. This design breaks the limitation of traditional PID repair equipment that usually only supports a single polarity, making the same device compatible with mainstream P-type and N-type photovoltaic modules on the market. This significantly broadens the application range of the equipment, reduces the user's equipment purchase and maintenance costs, and improves the overall compatibility and deployment convenience of the photovoltaic and energy storage system.

[0017] 3. The wide-voltage input flyback converter module supports a wide input voltage range of 300-1000VDC, which can be directly connected to the DC bus of the photovoltaic-storage system with large fluctuations and convert it into a stable DC voltage. This wide input range design enables the repair power supply to adapt to voltage fluctuations generated by photovoltaic arrays of different sizes and configurations, ensuring stable operation under harsh grid conditions or load changes. This enhances the robustness and reliability of the system in complex application scenarios and reduces the risk of failure due to voltage mismatch.

[0018] 4. As the core control unit, the intelligent control module can obtain repair mode instructions through various means such as local hardware settings, remote energy management system commands, or automatic identification based on photovoltaic module parameters, and accurately control polarity switching. This intelligent control strategy not only realizes flexible selection and remote management of repair modes, providing convenience for the integration of smart energy systems, but also reduces manual intervention through automatic identification, lowers the error rate of operation, and improves the efficiency and intelligence level of the entire PID repair process.

[0019] 5. The current-limiting output module uses high-resistance power resistors to strictly limit the maximum repair current to below 20mA, effectively preventing secondary damage to the photovoltaic modules caused by overcurrent. At the same time, the intelligent control module adopts a "turn off first, switch then restore" timing control when driving polarity switching. That is, the output of the wide voltage input flyback converter module is stopped first, and the power supply is restored after the relay completes the switching. This avoids arcing and voltage spikes during the switching process, protects the switching elements and subsequent circuits, and significantly improves the electrical safety and long-term operational reliability of the system.

[0020] 6. The modular design, such as the use of an integrated MOSFET flyback controller IC and a high-frequency transformer, achieves efficient and compact power conversion and electrical isolation; the polarity switching module uses a single-pole double-throw high-voltage relay, which is simple in structure, low in cost, and reliable in drive; the entire system has a low rated power (5W-15W) and low energy consumption, making it very suitable for long-term online operation in photovoltaic energy storage systems; these designs optimize material costs, assembly complexity, and space occupation while ensuring functional integrity and performance, demonstrating good engineering feasibility and economy.

[0021] 7. All-weather, all-condition repair capability: Through wide voltage input design and intelligent condition recognition, it ensures continuous operation of the repair power supply in various operating modes of the photovoltaic-energy storage system (daytime, nighttime, grid-connected, off-grid), solving the problem of traditional repair devices failing at night or under low voltage conditions; Intelligence and adaptability: It can automatically adjust repair parameters according to system status, achieving the best balance between repair effect and system energy consumption, avoiding negative impacts on other system functions (especially energy storage) during the repair process; High system integration and coordination: Through communication, it links with the entire photovoltaic-energy storage system, no longer an independent "dumb device," but as part of the intelligent energy management system, achieving collaborative optimization control; Inheriting the advantages of self-powered operation: It still does not require an external auxiliary power supply, directly drawing power from DC. Busbar power supply, compact structure, and high cost-effectiveness; Dual-mode operation with intelligent switching: By using a single flyback power supply in conjunction with a high-voltage relay, the output switching between positive and negative repair voltages is cleverly achieved. One set of equipment can meet the repair needs of both N-type and P-type modules, greatly improving the equipment's versatility and cost-effectiveness; Low power and wide voltage adaptability: Designed specifically for low power consumption of 10W, it has minimal impact on the energy consumption of the photovoltaic-storage system, making it particularly suitable for maintenance at night when powered by batteries; A wide input range of 300-1000V ensures stable operation even when the DC bus voltage of the photovoltaic-storage system fluctuates significantly; High safety and reliability: A current-limiting resistor is connected in series at the output end to effectively suppress surge current and ensure the safety of the repair process; The flyback topology itself has inherent electrical isolation characteristics, improving system safety. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] Figure 1 This is a circuit block diagram of an adaptive polarity PID repair power supply for a photovoltaic energy storage system according to the present invention. Detailed Implementation

[0024] Please refer to Figure 1 As shown, a preferred embodiment of the adaptive polarity PID repair power supply for a photovoltaic energy storage system according to the present invention includes: A wide-voltage input flyback converter module is used to convert a wide range of fluctuating DC bus voltage into a stable DC voltage; A polarity switching module is provided, with its input terminal connected to the output terminal of the wide voltage input flyback converter module; the polarity switching module is equipped with a controlled switching switching element. An intelligent control module, electrically connected to the polarity switching module, is used to output a control signal according to the input repair mode command to drive the switching element to switch states. A current-limiting output module is connected in series in the output circuit of the polarity switching module; The polarity switching module is configured to respond to the control signal from the intelligent control module, and has a first operating mode and a second operating mode: In the first working mode, the current limiting output module outputs a repair voltage that is negative relative to ground, which is suitable for PID repair of P-type photovoltaic modules; In the second operating mode, the current limiting output module outputs a repair voltage that is positive relative to ground, which is suitable for PID repair of N-type photovoltaic modules.

[0025] The wide voltage input flyback converter module uses an integrated MOSFET flyback switching power supply controller IC and includes a high-frequency transformer that provides electrical isolation.

[0026] The wide voltage input flyback converter module includes the following components: Input protection circuit: Used to prevent abnormal input voltage or current from damaging subsequent circuits; EMI filter circuit: used to suppress high-frequency noise generated by the power module itself and prevent it from interfering with the DC bus or other equipment; Flyback switching power supply controller IC: The core control chip of the module, which integrates power MOSFETs and controllers, such as the InnoSwitch3 series. This series of ICs integrates MOSFETs with a withstand voltage of 725V or higher and controllers, and can directly withstand input voltages of 300-1000VDC without the need for external discrete MOSFETs, thus simplifying the design. High-frequency transformer: a key magnetic component for voltage transformation and electrical isolation; primary winding: connected to the input circuit; auxiliary winding: provides operating power (Vcc) for the flyback controller IC; secondary high-voltage winding: generates the required high-voltage output; the primary inductance of the high-frequency transformer needs to be precisely calculated to ensure no current flow at the lowest input voltage (300VDC) and a high conversion efficiency at the highest input voltage (1000VDC); the magnetic core should be selected such as EFD25 or PQ26 to ensure unsaturation and controllable temperature rise at 10W power; the winding structure is: primary winding -> auxiliary winding (powering the controller IC) -> secondary high-voltage winding; the insulation level must meet the requirements for reinforced insulation.

[0027] RCD clamping circuit: Composed of resistors, capacitors and diodes, it is used to absorb the voltage spikes generated when the primary winding of the transformer is turned off and protect the integrated power MOSFET. Secondary rectifier diodes: rectify the high-frequency AC voltage generated by the secondary winding of the transformer and convert it into DC voltage; Secondary filter capacitor: Smooths and filters the rectified DC voltage to obtain a stable 500VDC output; Feedback circuit: Used to monitor the output voltage and achieve precise voltage regulation, mainly including: The sampling resistor divider network divides the output 500V high voltage to obtain a processable low-voltage sample; a precision reference source, such as TL431, compares the sampled voltage with an internal reference (e.g., 2.5V); and an optocoupler, such as PC817, isolates the voltage error signal on the secondary side and transmits it to the primary-side flyback controller IC, achieving closed-loop control. The feedback circuit samples the output voltage (500VDC), divides it using resistors, and compares it with the 2.5V reference of TL431. This controls the light intensity of the optocoupler, thereby isolating the output voltage error signal and transmitting it to the primary-side controller, achieving precise closed-loop voltage regulation.

[0028] The connection relationship (power flow) of the main power path of the wide voltage input flyback converter module is as follows: Input terminals: The positive and negative terminals of the DC bus (PV+ / PV-) are first connected to the input terminals of the input protection circuit.

[0029] Filtering: The output of the input protection circuit is connected to the input of the EMI filter circuit.

[0030] Power conversion: The filtered wide-range DC power (300-1000V) output from the EMI filter circuit is applied to one end of the primary winding of the high-frequency transformer; the other end of the primary winding is connected to the drain of the power MOSFET integrated inside the flyback controller IC.

[0031] Clamping protection: The RCD clamping circuit is connected in parallel across the two ends of the primary winding of the transformer to absorb leakage inductance energy.

[0032] Rectification and Filtering: The AC high voltage generated by the secondary high voltage winding of the high-frequency transformer is first rectified by the secondary rectifier diodes, and then sent to the secondary filter capacitor for filtering. Finally, a stable +500V output is obtained at both ends of the capacitor (this point is the common input terminal of the subsequent polarity switching module).

[0033] The connection relationship (signal flow) between the control and feedback paths of the wide voltage input flyback converter module is as follows: IC power supply: When the high-frequency transformer is working, the voltage induced on its auxiliary winding is rectified and filtered to provide the working power (Vcc) for the flyback controller IC.

[0034] Voltage sampling: The final output of the module (i.e. the voltage across the secondary filter capacitor) is sampled by the sampling resistor voltage divider network to obtain a low-voltage signal proportional to the output voltage.

[0035] Error Comparison: The sampled signal is sent to the reference terminal of a precision reference source (such as TL431) and compared with the internal reference voltage to generate an error signal.

[0036] Isolation feedback: This error signal controls the brightness of the LED in the optocoupler, thereby changing the conduction state of the phototransistor inside the optocoupler. The secondary side of the optocoupler is connected to the feedback pin of the flyback controller IC, thus "telling" the primary-side control chip about the stability of the output voltage in an optically isolated manner.

[0037] Closed-loop regulation: The flyback controller IC dynamically adjusts the switching frequency or duty cycle of its internal power MOSFETs based on the received feedback signal, thereby achieving precise closed-loop voltage regulation and ensuring that the output voltage remains stable at 500VDC regardless of input voltage fluctuations.

[0038] The wide voltage input flyback converter module has an input voltage range of 300-1000VDC, an output DC voltage of 500VDC, and a rated output power of 5W to 15W.

[0039] The switching element is a single-pole double-throw high-voltage relay. Its contact material must be able to withstand the erosion of electric arc under DC load. The rated switching voltage must be ≥600VDC and the current ≥50mA (such as the EV200 series from Tyco Electronics). The coil drive circuit of the single-pole double-throw high-voltage relay is composed of the GPIO port of the intelligent control module -> transistor (such as S8050) or MOSFET switching circuit -> relay coil. The GPIO output high / low level controls the on / off of the transistor, thereby controlling the single-pole double-throw high-voltage relay to engage and disengage.

[0040] The common terminal of the single-pole double-throw high-voltage relay is connected to the positive output terminal of the wide voltage input flyback converter module; The normally closed contact of the single-pole double-throw high-voltage relay forms the output path of the first working mode, and the normally open contact forms the output path of the second working mode. The coil of the single-pole double-throw high-voltage relay is driven by the control signal of the intelligent control module.

[0041] Polarity switching logic of a single-pole double-throw high-voltage relay: P-type mode (default): The intelligent control module outputs a low level GPIO, and the relay does not operate; the +500V output from the flyback power supply is connected to the "P-type output terminal" through the normally closed contact (NC) of the relay; at this time, the "P-type output terminal" is -500V relative to the grounded "ground terminal".

[0042] N-type mode: The intelligent control module outputs a high level GPIO, and the relay is energized; the +500V output from the flyback power supply is connected to the "N-type output terminal" through the normally open contact (NO) of the relay; at this time, the "N-type output terminal" is +500V relative to the grounded "ground terminal".

[0043] When the intelligent control module issues a control signal, it first controls the wide voltage input flyback converter module to stop outputting. After the switching element completes its state switching, it then controls the wide voltage input flyback converter module to resume outputting.

[0044] The intelligent control module is a microcontroller, which acquires the repair mode command through at least one of the following methods: Receive signals from local hardware settings components; Receive communication commands from the remote energy management system; Automatic identification and judgment are based on the detection of electrical parameters of photovoltaic modules.

[0045] The intelligent control module includes the following components: Microcontroller (MCU): The core processing unit of the module, such as STM32F030, GD32E230 or TMS320F280025PNS, is the physical basis for all logical judgments and command generation.

[0046] Essential peripheral circuits for the MCU: Clock circuit: composed of a crystal oscillator and matching capacitors, providing the operating clock for the MCU; Reset circuit: composed of a power-on reset chip or a simple RC circuit, ensuring that the MCU can start normally when the power supply is unstable; Power supply decoupling capacitors: distributed near the power supply pins of the MCU, used to filter out high-frequency noise and stabilize the power supply voltage. Status detection circuit: The core is a resistor voltage divider network that proportionally attenuates high voltage (such as 1000V) to a low voltage (such as 3.3V) that can be safely sampled by the MCU's internal ADC. Command input interface circuit: such as DIP switch or button, directly connected to MCU through GPIO port for local manual setting of working mode; Control signal output circuit: It consists of a current-limiting resistor and a switching transistor (such as S8050) or MOSFET, which is used to amplify the current drive capability of the MCU GPIO port to control the relay coil; Communication modules: such as Wi-Fi modules (ESP8266), NB-IoT modules, or PLC carrier communication modules. These modules connect to the MCU through interfaces such as serial port (UART) and SPI.

[0047] The entire intelligent control module is powered by the auxiliary winding of the wide-input flyback converter module. The voltage output from this auxiliary winding is rectified and regulated to serve as VCC_MCU, which is directly connected to the MCU's power supply pins (VDD / VSS). The clock circuit (two pins of the crystal oscillator) is connected to the MCU's dedicated clock pins (OSC_IN / OSC_OUT). The output of the reset circuit is connected to the MCU's reset pin (NRST). One end of the power supply decoupling capacitor is connected to the MCU's power supply pin, and the other end is connected to the power ground. The high-voltage end of the status detection circuit is connected to the DC bus, the low-voltage end is grounded, and the midpoint of the voltage divider is connected to an analog input pin (ADC pin) of the MCU. The MCU reads the voltage value of this pin and calculates the actual DC bus voltage. One end of the instruction input interface circuit is connected to VCC_MCU or... One end is connected to ground, and the other end is connected directly to a digital input pin (GPIO) of the MCU through a pull-up / pull-down resistor. The MCU reads the level state of the GPIO when powered on to determine the initial operating mode. One digital output pin (GPIO) of the MCU is connected to one end of a base current-limiting resistor, and the other end of the current-limiting resistor is connected to the base of a switching transistor. The emitter of the transistor is grounded, and the collector is connected to one end of a relay coil (the other end of the coil is connected to the drive power supply Vcc_Relay). A freewheeling diode is connected in parallel across the two ends of the relay coil. When the MCU's GPIO outputs a high level, the transistor is turned on, and the relay coil is energized and energized. When the output is low, the transistor is turned off, and the relay is released. The MCU's serial port transmit pin (TX) and serial port receive pin (RX) are connected to the RX and TX pins of a communication module (such as a Wi-Fi module), respectively.

[0048] The current-limiting output module includes at least one high-resistance power resistor with a resistance range of 25kΩ to 1MΩ, used to limit the maximum repair current to below 20mA.

[0049] Resistance parameter calculation and selection: According to Ohm's law I=V / R, to ensure safety, the repair current is limited to I_repair<20mA. Given the output voltage V=500V, the current-limiting resistor R_limit>500V / 20mA=25kΩ.

[0050] Select a resistor with a nominal resistance of 68kΩ. The theoretical maximum current is 7.3mA, leaving ample margin.

[0051] The resistor power calculation is P=I²*R=(0.0073A)²*68,000Ω=3.6W; to ensure long-term reliability, select a 5W or higher power ceramic package or aluminum shell package power resistor, and consider reserving sufficient heat dissipation space on the PCB.

[0052] The current-limiting resistor (R_limit) is connected in series after the common output path of the high-voltage relay. That is, whether it is a P-type or N-type path, the current must flow through this resistor before being output to the component. This design achieves common current-limiting protection for both paths with a single resistor.

[0053] Working principle of this invention: The wide-voltage input flyback converter module first draws power from the DC bus of the photovoltaic-storage system, converting the wide-range fluctuating voltage of 300-1000VDC into a stable 500VDC output through flyback conversion and high-frequency transformer isolation, ensuring continuous operation when off-grid or during voltage fluctuations. The intelligent control module outputs control signals to drive the single-pole double-throw high-voltage relay in the polarity switching module to switch states according to local settings, remote commands, or automatic detection repair mode commands. Before switching, the flyback module output is turned off to avoid arcing. After the single-pole double-throw high-voltage relay completes its action, power supply is restored, thereby achieving a first working mode output with a negative repair voltage relative to ground for P-type photovoltaic module PID repair, or a second working mode output with a positive repair voltage relative to ground for N-type module repair. At the same time, the current-limiting output module is connected in series with a high-resistance power resistor to limit the maximum repair current to below 20mA to prevent overcurrent damage. Finally, through this adaptive polarity switching and intelligent collaboration, all-weather, safe and efficient PID repair is achieved.

[0054] In summary, the advantages of this invention are as follows: 1. By adopting a wide-voltage input flyback converter module that draws power directly from the DC bus of the photovoltaic-storage system, the system effectively adapts to large-scale fluctuations in bus voltage and ensures continuous and stable operation under off-grid conditions, thereby significantly improving the adaptability of the power supply. Through a polarity switching module driven by an intelligent control module, the polarity of the output repair voltage is flexibly controllable, enabling it to automatically adapt to different types of photovoltaic modules, such as P-type and N-type, greatly enhancing the power supply's compatibility. Simultaneously, the intelligent control module can receive local settings, remote system commands, or dynamically adjust the operating mode based on automatic detection results, enabling information interaction and strategy coordination between the repair power supply and the upper-level energy management system. This ultimately achieves a leap in intelligence, improves overall synergy, and significantly enhances the adaptability, compatibility, and synergy of the PID repair power supply.

[0055] 2. By integrating a polarity switching module and an intelligent control module, the adaptive switching of the power supply output polarity is achieved. It can output negative voltage to repair P-type photovoltaic modules in the first working mode and output positive voltage to repair N-type photovoltaic modules in the second working mode. This design breaks the limitation of traditional PID repair equipment that usually only supports a single polarity, making the same device compatible with mainstream P-type and N-type photovoltaic modules on the market. This significantly broadens the application range of the equipment, reduces the user's equipment purchase and maintenance costs, and improves the overall compatibility and deployment convenience of the photovoltaic and energy storage system.

[0056] 3. The wide-voltage input flyback converter module supports a wide input voltage range of 300-1000VDC, which can be directly connected to the DC bus of the photovoltaic-storage system with large fluctuations and convert it into a stable DC voltage. This wide input range design enables the repair power supply to adapt to voltage fluctuations generated by photovoltaic arrays of different sizes and configurations, ensuring stable operation under harsh grid conditions or load changes. This enhances the robustness and reliability of the system in complex application scenarios and reduces the risk of failure due to voltage mismatch.

[0057] 4. As the core control unit, the intelligent control module can obtain repair mode instructions through various means such as local hardware settings, remote energy management system commands, or automatic identification based on photovoltaic module parameters, and accurately control polarity switching. This intelligent control strategy not only realizes flexible selection and remote management of repair modes, providing convenience for the integration of smart energy systems, but also reduces manual intervention through automatic identification, lowers the error rate of operation, and improves the efficiency and intelligence level of the entire PID repair process.

[0058] 5. The current-limiting output module uses high-resistance power resistors to strictly limit the maximum repair current to below 20mA, effectively preventing secondary damage to the photovoltaic modules caused by overcurrent. At the same time, the intelligent control module adopts a "turn off first, switch then restore" timing control when driving polarity switching. That is, the output of the wide voltage input flyback converter module is stopped first, and the power supply is restored after the relay completes the switching. This avoids arcing and voltage spikes during the switching process, protects the switching elements and subsequent circuits, and significantly improves the electrical safety and long-term operational reliability of the system.

[0059] 6. The modular design, such as the use of an integrated MOSFET flyback controller IC and a high-frequency transformer, achieves efficient and compact power conversion and electrical isolation; the polarity switching module uses a single-pole double-throw high-voltage relay, which is simple in structure, low in cost, and reliable in drive; the entire system has a low rated power (5W-15W) and low energy consumption, making it very suitable for long-term online operation in photovoltaic energy storage systems; these designs optimize material costs, assembly complexity, and space occupation while ensuring functional integrity and performance, demonstrating good engineering feasibility and economy.

[0060] 7. All-weather, all-condition repair capability: Through wide voltage input design and intelligent condition recognition, it ensures continuous operation of the repair power supply in various operating modes of the photovoltaic-energy storage system (daytime, nighttime, grid-connected, off-grid), solving the problem of traditional repair devices failing at night or under low voltage conditions; Intelligence and adaptability: It can automatically adjust repair parameters according to system status, achieving the best balance between repair effect and system energy consumption, avoiding negative impacts on other system functions (especially energy storage) during the repair process; High system integration and coordination: Through communication, it links with the entire photovoltaic-energy storage system, no longer an independent "dumb device," but as part of the intelligent energy management system, achieving collaborative optimization control; Inheriting the advantages of self-powered operation: It still does not require an external auxiliary power supply, directly drawing power from DC. Busbar power supply, compact structure, and high cost-effectiveness; Dual-mode operation with intelligent switching: By using a single flyback power supply in conjunction with a high-voltage relay, the output switching between positive and negative repair voltages is cleverly achieved. One set of equipment can meet the repair needs of both N-type and P-type modules, greatly improving the equipment's versatility and cost-effectiveness; Low power and wide voltage adaptability: Designed specifically for low power consumption of 10W, it has minimal impact on the energy consumption of the photovoltaic-storage system, making it particularly suitable for maintenance at night when powered by batteries; A wide input range of 300-1000V ensures stable operation even when the DC bus voltage of the photovoltaic-storage system fluctuates significantly; High safety and reliability: A current-limiting resistor is connected in series at the output end to effectively suppress surge current and ensure the safety of the repair process; The flyback topology itself has inherent electrical isolation characteristics, improving system safety.

[0061] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An adaptive polarity PID repair power supply for a photovoltaic energy storage system, characterized in that: include: A wide-voltage input flyback converter module is used to convert a wide range of fluctuating DC bus voltage into a stable DC voltage; A polarity switching module is provided, with its input terminal connected to the output terminal of the wide voltage input flyback converter module; the polarity switching module is equipped with a controlled switching switching element. An intelligent control module, electrically connected to the polarity switching module, is used to output a control signal according to the input repair mode command to drive the switching element to switch states. A current-limiting output module is connected in series in the output circuit of the polarity switching module; The polarity switching module is configured to respond to the control signal from the intelligent control module, and has a first operating mode and a second operating mode: In the first working mode, the current limiting output module outputs a repair voltage that is negative relative to ground, which is suitable for PID repair of P-type photovoltaic modules; In the second operating mode, the current limiting output module outputs a repair voltage that is positive relative to ground, which is suitable for PID repair of N-type photovoltaic modules.

2. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: The wide voltage input flyback converter module uses an integrated MOSFET flyback switching power supply controller IC and includes a high-frequency transformer that provides electrical isolation.

3. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: The wide voltage input flyback converter module has an input voltage range of 300-1000VDC, an output DC voltage of 500VDC, and a rated output power of 5W to 15W.

4. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: The switching element is a single-pole double-throw high-voltage relay; The common terminal of the single-pole double-throw high-voltage relay is connected to the positive output terminal of the wide voltage input flyback converter module; The normally closed contact of the single-pole double-throw high-voltage relay forms the output path of the first working mode, and the normally open contact forms the output path of the second working mode. The coil of the single-pole double-throw high-voltage relay is driven by the control signal of the intelligent control module.

5. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: When the intelligent control module issues a control signal, it first controls the wide voltage input flyback converter module to stop outputting. After the switching element completes its state switching, it then controls the wide voltage input flyback converter module to resume outputting.

6. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: The intelligent control module is a microcontroller, which acquires the repair mode command through at least one of the following methods: Receive signals from local hardware settings components; Receive communication commands from the remote energy management system; Automatic identification and judgment are based on the detection of electrical parameters of photovoltaic modules.

7. The adaptive polarity PID repair power supply for a photovoltaic energy storage system as described in claim 1, characterized in that: The current-limiting output module includes at least one high-resistance power resistor with a resistance range of 25kΩ to 1MΩ, used to limit the maximum repair current to below 20mA.

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