Over-temperature fault detection method for connectors and photovoltaic terminals

Abstract

The application discloses a kind of connector and photovoltaic terminal over-temperature fault detection method, belong to electronic power technical field.The connector includes: insulating shell;Photovoltaic terminal, at least part is set in the inside of insulating shell, for realizing the electrical connection of cable and mating component;Temperature detection device, is set to the crimping area of photovoltaic terminal and cable, with photovoltaic terminal thermal coupling, for collecting the temperature of photovoltaic terminal;Lead wire, with temperature detection device electrical connection, along cable direction setting, for transmission temperature.The embodiment of the application is set to the crimping area of photovoltaic terminal and cable by temperature detection device, and make temperature detection device and photovoltaic terminal form thermal coupling, shorten the heat conduction path of heat generated when photovoltaic terminal works, reduce the loss of heat in transmission process, to improve the accuracy of photovoltaic terminal temperature detection.

Description

Technical Field

[0001] This application belongs to the field of electronic power technology, and in particular relates to a method for detecting over-temperature faults in connectors and photovoltaic terminals. Background Technology

[0002] In the photovoltaic (PV) industry, due to factors such as supply chain compatibility, on-site spare parts replacement, and construction practices, PV terminal cores from different manufacturers are sometimes used interchangeably. Impedance differences caused by contact issues can lead to loose connections and burnout during long-term operation. Therefore, it is necessary to monitor the temperature of PV terminals to detect connection abnormalities early and prevent thermal failures.

[0003] In related technologies, multiple insulating and thermally conductive layers are installed inside the inverter to conduct the heat generated by the photovoltaic terminals during operation to the corresponding insulating and thermally conductive layers via conductive paths. A temperature detection circuit then collects the temperature signals of each insulating and thermally conductive layer to obtain the real-time temperature of each photovoltaic terminal. However, this method results in an excessively long heat conduction path, leading to significant heat loss during the transfer process and reducing the accuracy of temperature detection. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes an over-temperature fault detection method for connectors and photovoltaic terminals to improve the accuracy of photovoltaic terminal temperature detection.

[0005] In a first aspect, this application provides a connector, comprising: Insulating outer casing; Photovoltaic terminals, at least partially disposed inside the insulating housing, are used to achieve electrical connection between the cable and the docking component; A temperature sensing device is disposed in the crimping area between the photovoltaic terminal and the cable, and is thermally coupled to the photovoltaic terminal to collect the temperature of the photovoltaic terminal; A lead wire, electrically connected to the temperature sensing device, is arranged along the direction of the cable and is used to transmit the temperature.

[0006] According to the connector of this application, by placing the temperature sensing device in the crimping area between the photovoltaic terminal and the cable, and making the temperature sensing device thermally coupled with the photovoltaic terminal, and arranging the lead wire along the cable direction, the normal electrical connection and mechanical performance of the photovoltaic cable are not affected, thereby realizing the integration of the temperature sensing device and the connector. Since the heat does not need to be transferred step by step through multiple layers of insulating thermal conductive layers and conductive paths, the heat conduction path of the heat generated when the photovoltaic terminal is working is shortened, the heat loss in the transfer process is reduced, thereby improving the accuracy of the temperature detection of the photovoltaic terminal.

[0007] According to one embodiment of this application, the temperature sensing device is a thermistor, and the thermistor is externally coated with epoxy resin.

[0008] In this embodiment, by selecting a thermistor as the temperature detection device, the temperature change of the photovoltaic terminal can be quickly sensed, improving the response efficiency and accuracy of temperature detection. The epoxy resin coating on the outside of the thermistor can reduce the interference of impurities such as water vapor and dust in the external environment on the thermistor, improve the working stability of the thermistor, and also form thermal coupling with the photovoltaic terminal, improving the accuracy of temperature detection.

[0009] According to one embodiment of this application, a structural window is provided on the crimping area, and the temperature measuring head of the temperature detection device is located on the outer periphery of the opening of the structural window away from the photovoltaic terminal, or at least partially extends into the interior of the structural window.

[0010] In this embodiment, by setting a structural window in the pressing area and arranging the temperature sensing head of the temperature detection device on the outer periphery of the opening of the structural window away from the photovoltaic terminal or at least partially extending into the structural window, the temperature sensing head can approach the photovoltaic terminal in a low-cost and reliable manner. When the temperature sensing head is set on the outer periphery of the opening, indirect contact measurement is formed between the temperature sensing head and the photovoltaic terminal, reducing the electrical safety risks that may be caused by direct contact. When the temperature sensing head is at least partially extended into the structural window, the heat conduction distance between the temperature sensing head and the photovoltaic terminal is shortened, and the response sensitivity of temperature measurement is improved.

[0011] According to one embodiment of this application, there is a gap between the temperature sensing head of the temperature sensing device and the photovoltaic terminal, and thermal coupling is achieved through air heat transfer; or, the temperature sensing head of the temperature sensing device is in contact with the photovoltaic terminal, and thermal coupling is achieved through solid conduction.

[0012] In this embodiment, by using air heat transfer, the gap between the temperature sensor and the photovoltaic terminal forms electrical isolation, reducing the risk of electrical short circuit between the temperature detection device and the photovoltaic terminal and improving the safety of temperature detection. By using solid conduction, the temperature sensor is in direct contact with the photovoltaic terminal, shortening the heat conduction path and reducing heat transfer loss, thereby improving the response speed and detection accuracy of temperature detection.

[0013] According to one embodiment of this application, a plurality of the connectors are connected to the same docking component, which is an inverter.

[0014] In this embodiment, by connecting multiple connectors to the same inverter, the temperature signals of each photovoltaic terminal collected by the temperature detection device can be transmitted centrally through the lead wires. The temperature information of each photovoltaic terminal, the loop current information, and the inverter's own operating status information can be fused and analyzed on the same platform, which improves operation and maintenance efficiency.

[0015] Secondly, this application provides a method for detecting over-temperature faults in photovoltaic terminals, including: The temperature of the photovoltaic terminal transmitted by the temperature sensing device in the multiple connectors mentioned above through the lead wire is obtained, as well as the loop current of the circuit in which each connector is located; The current-carrying state of each connector in the circuit is identified based on the circuit current; When the current-carrying state is normal, the theoretical temperature rise of each photovoltaic terminal is calculated based on the current of each circuit, and the measured temperature rise of each photovoltaic terminal is obtained based on the temperature of each photovoltaic terminal. The difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal, are used to identify whether the photovoltaic terminal is overheating.

[0016] According to the photovoltaic terminal over-temperature fault detection method of this application, the temperatures of multiple photovoltaic terminals are acquired, and the loop current is acquired to identify the current-carrying state. Under the condition of normal current carrying, the theoretical temperature rise value is calculated based on the loop current and the measured temperature rise value is calculated based on the measured temperature. Since the theoretical temperature rise value reflects the expected thermal equilibrium temperature of the photovoltaic terminal under normal electrical connection state, and the measured temperature rise value reflects the actual thermal state of the photovoltaic terminal, the difference between the measured temperature rise value and the theoretical temperature rise value can assess whether the photovoltaic terminal has over-temperature. Furthermore, by comparing the temperature differences between each photovoltaic terminal, the influence of external factors such as changes in ambient temperature, illumination, system operating conditions, and temperature detection device failure can be distinguished, thereby improving the accuracy of photovoltaic terminal over-temperature fault detection.

[0017] According to one embodiment of this application, the leads of a plurality of connectors are connected to the same signal connector, and the step of obtaining the temperature of the photovoltaic terminal transmitted by the temperature sensing device of the plurality of connectors through the leads includes: The temperature of the photovoltaic terminal is obtained by means of the temperature sensing device in the multiple connectors mentioned above, which transmits the temperature through the lead wire.

[0018] In this embodiment, by connecting the lead wires of multiple connectors to the same signal connector, the temperature signals of each photovoltaic terminal collected by the temperature detection device can be centrally acquired through the same signal connector, realizing the centralized transmission of multiple terminal temperature signals and reducing the number of signal acquisition channels and wiring complexity.

[0019] According to one embodiment of this application, the method further includes: When the current-carrying state is a low current-carrying state or an empty current-carrying state, if there is a photovoltaic terminal with a temperature greater than or equal to a first temperature threshold, at least one of the following is obtained: the temperature change rate of each photovoltaic terminal, the current change rate of the circuit it is in, and the temperature difference between each photovoltaic terminal and other photovoltaic terminals. If the temperature change rate is greater than a first change rate threshold and the current change rate is less than or equal to a second change rate threshold, and / or the temperature difference is greater than a second temperature threshold, it is determined that there is an abnormality in the temperature detection device.

[0020] In this embodiment, the temperature detection device is diagnosed for anomalies when the current carrying state is low or no current carrying state. Since the theoretical heat generation of the photovoltaic terminal is low when the current carrying state is low or no current carrying state, the temperature should be close to the ambient temperature or in a low state. Therefore, when a photovoltaic terminal with a temperature greater than or equal to the first temperature threshold is detected, the temperature change rate, current change rate and temperature difference with other photovoltaic terminals are further obtained. When the temperature change rate is greater than the first change rate threshold and the current change rate is less than or equal to the second change rate threshold, it indicates that the temperature rise trend is unrelated to the electrical load, and the temperature rise caused by load fluctuation is ruled out. If the temperature difference with other photovoltaic terminals is greater than the second temperature threshold, it is confirmed that the abnormal temperature rise is a local anomaly, so it can be confirmed that it is a fault of the temperature detection device itself, rather than an over-temperature fault, thus reducing the risk of false alarms in the judgment of over-temperature faults.

[0021] According to one embodiment of this application, identifying whether a photovoltaic terminal has an over-temperature fault based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal, includes: If the difference between the measured temperature rise and the theoretical temperature rise is greater than the third temperature threshold and the duration is greater than or equal to the target duration threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, an over-temperature fault is determined to exist.

[0022] In this embodiment, since the difference between the measured temperature rise and the theoretical temperature rise reflects the deviation of the actual thermal state of the photovoltaic terminal from the expected thermal state, if the deviation persists for a certain period of time, it eliminates the possibility of transient temperature rise fluctuations caused by instantaneous current surges or measurement noise. If the temperature difference between at least one group of photovoltaic terminals is greater than or equal to the fourth temperature threshold, it further indicates that the temperature distribution of multiple photovoltaic terminals does not conform to the consistency characteristics. The abnormal temperature rise is a photovoltaic terminal over-temperature fault rather than an overall temperature rise caused by factors such as changes in ambient temperature or uneven sunlight. This improves the accuracy and anti-interference ability of photovoltaic terminal over-temperature fault detection and reduces the risk of false alarms caused by operating condition fluctuations or environmental factors.

[0023] According to one embodiment of this application, the method further includes: If the difference between the measured temperature rise and the theoretical temperature rise is less than or equal to the third temperature threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, it is determined that there is an abnormality in the temperature detection device.

[0024] In this embodiment, since the difference between the measured temperature rise and the theoretical temperature rise is within the normal range, it indicates that the expected thermal state calculated based on the electrical load is consistent with the actual thermal state, and the photovoltaic terminal itself does not have an over-temperature fault. In this case, if the temperature difference between at least one group of photovoltaic terminals is too large, it indicates that the temperature distribution of multiple photovoltaic terminals does not conform to the consistency characteristics. Therefore, it can be concluded that the local temperature difference is caused by the measurement abnormality of the temperature detection device itself, which reduces the risk of false alarm in the judgment of over-temperature fault.

[0025] Thirdly, this application provides an over-temperature fault detection device for photovoltaic terminals, comprising: The first acquisition module is used to acquire the temperature of the photovoltaic terminal transmitted by the temperature detection device in the plurality of connectors through the lead wire, and to acquire the loop current of the circuit in which each connector is located. The first identification module is used to identify the current-carrying state of the circuit in which each connector is located based on the circuit current. The second acquisition module is used to calculate the theoretical temperature rise of each photovoltaic terminal based on the current of each circuit when the current carrying state is normal, and to obtain the measured temperature rise of each photovoltaic terminal based on the temperature of each photovoltaic terminal. The second identification module is used to identify whether the photovoltaic terminal has an over-temperature fault based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal.

[0026] According to the photovoltaic terminal over-temperature fault detection device of this application, the temperature of multiple photovoltaic terminals is acquired, and the loop current is acquired to identify the current carrying state. Under the condition of normal current carrying, the theoretical temperature rise value is calculated based on the loop current and the measured temperature rise value is calculated based on the measured temperature. Since the theoretical temperature rise value reflects the expected thermal equilibrium temperature of the photovoltaic terminal under normal electrical connection state, and the measured temperature rise value reflects the actual thermal state of the photovoltaic terminal, the difference between the measured temperature rise value and the theoretical temperature rise value can assess whether the photovoltaic terminal has over-temperature. Furthermore, by comparing the temperature differences between each photovoltaic terminal, the influence of external factors such as changes in ambient temperature, illumination, system operating conditions, and temperature detection device failure can be distinguished, thereby improving the accuracy of photovoltaic terminal over-temperature fault detection.

[0027] Fourthly, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-mentioned method for detecting over-temperature faults in photovoltaic terminals.

[0028] Fifthly, this application provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-mentioned method for detecting over-temperature faults in photovoltaic terminals.

[0029] Sixthly, this application provides a chip, the chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the above-mentioned method for detecting over-temperature faults in photovoltaic terminals.

[0030] The above-described one or more technical solutions in the embodiments of this application have at least one of the following technical effects: According to the connector of this application, by placing the temperature sensing device in the crimping area between the photovoltaic terminal and the cable, and making the temperature sensing device thermally coupled with the photovoltaic terminal, and arranging the lead wire along the cable direction, the normal electrical connection and mechanical performance of the photovoltaic cable are not affected, thereby realizing the integration of the temperature sensing device and the connector. Since the heat does not need to be transferred step by step through multiple layers of insulating thermal conductive layers and conductive paths, the heat conduction path of the heat generated when the photovoltaic terminal is working is shortened, the heat loss in the transfer process is reduced, thereby improving the accuracy of the temperature detection of the photovoltaic terminal.

[0031] In some embodiments, by selecting a thermistor as a temperature sensing device, the temperature change of the photovoltaic terminal can be quickly sensed, improving the response efficiency and accuracy of temperature detection. The epoxy resin coating on the outside of the thermistor can reduce the interference of impurities such as water vapor and dust in the external environment on the thermistor, improve the working stability of the thermistor, and also form thermal coupling with the photovoltaic terminal, thereby improving the accuracy of temperature detection.

[0032] In some embodiments, by setting a structural window in the crimping area and arranging the temperature sensing head of the temperature sensing device on the outer periphery of the opening of the structural window away from the photovoltaic terminal or at least partially extending into the structural window, the temperature sensing head can approach the photovoltaic terminal in a low-cost and reliable manner. When the temperature sensing head is set on the outer periphery of the opening, indirect contact measurement is formed between the temperature sensing head and the photovoltaic terminal, reducing the electrical safety risks that may be caused by direct contact. When the temperature sensing head is at least partially extended into the structural window, the heat conduction distance between the temperature sensing head and the photovoltaic terminal is shortened, and the response sensitivity of temperature measurement is improved.

[0033] In some embodiments, by employing air heat transfer, the gap between the temperature sensor and the photovoltaic terminal forms electrical isolation, reducing the risk of electrical short circuit between the temperature detection device and the photovoltaic terminal and improving the safety of temperature detection; by employing solid conduction, the temperature sensor and the photovoltaic terminal are in direct contact, shortening the heat conduction path and reducing heat transfer loss, thereby improving the response speed and detection accuracy of temperature detection.

[0034] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the connector structure provided in an embodiment of this application; Figure 2 This is a schematic diagram of the connection between the connector and the signal connector provided in the embodiments of this application; Figure 3 This is a flowchart illustrating the over-temperature fault detection method for photovoltaic terminals provided in this application embodiment; Figure 4 This is a schematic diagram illustrating a scenario example provided in the embodiments of this application; Figure 5 This is a schematic diagram of the structure of the photovoltaic terminal over-temperature fault detection device provided in the embodiments of this application; Figure 6 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0038] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0039] Photovoltaic connectors are interface components used in photovoltaic (PV) systems to connect PV modules, inverters, combiner boxes, and other equipment, typically used on the DC input side of the inverter. A PV connector includes an insulating shell, seals, a locking mechanism, and PV terminals. The PV terminals are the conductive components of the connector, made of copper alloy or tin-plated copper. One end connects to the PV cable via crimping or soldering, while the other end forms a mating contact with the inverter's DC busbar or corresponding socket, creating a current transmission path. During inverter operation, the Joule heat generated by the current flowing through the PV terminals, along with localized heating due to contact resistance, causes the terminal temperature to rise. Excessive temperature can lead to further increases in contact resistance, insulation aging, and even fire. Therefore, real-time monitoring of the temperature of each PV terminal is crucial for system safety.

[0040] In related technologies, multiple insulating and heat-conducting layers are mainly installed inside the inverter. The heat generated by the photovoltaic terminals during operation is conducted to the corresponding insulating and heat-conducting layers through conductive paths. Then, a temperature detection circuit collects the temperature signals of each insulating and heat-conducting layer to obtain the real-time temperature of each photovoltaic terminal. However, this method has an excessively long heat conduction path, resulting in significant heat loss during the transfer process and reducing the accuracy of temperature detection.

[0041] Based on this, embodiments of this application provide a method for detecting over-temperature faults in connectors and photovoltaic terminals. The over-temperature fault detection method for connectors and photovoltaic terminals provided in this application will be described in detail below with reference to the accompanying drawings and specific embodiments and application scenarios.

[0042] like Figure 1 As shown, this application provides a connector 100, including: Insulating outer casing 10; Photovoltaic terminal 20, disposed inside insulating housing 10, is used to realize electrical connection between cable 30 and docking component; Temperature sensing device 40 is disposed in the crimping area 50 between photovoltaic terminal 20 and cable 30, and is thermally coupled to photovoltaic terminal 20 for collecting temperature of photovoltaic terminal; Lead wire 60 is electrically connected to temperature sensing device 40 and is arranged along the direction of cable 30 for transmitting temperature.

[0043] In this embodiment, the insulating shell 10 is used to house and protect the internal electrical connection components of the connector 100, and to provide electrical insulation protection, reducing interference or damage to the internal conductive path of the connector 100 caused by external environmental factors. The insulating shell 10 can be made of engineering plastics or composite materials with excellent insulation properties, weather resistance and mechanical strength.

[0044] The insulating housing 10 has an internal cavity for securing the photovoltaic terminal 20, the temperature sensing device 40, and related conductive components. The shape and size of the cavity within the insulating housing 10 can be adapted to the structure of the photovoltaic terminal 20 and the connection method of the cable 30, ensuring a relatively stable relative positional relationship among the components after assembly. The insulating housing 10 also provides an entry channel for the cable 30 and an interface area for the mating components, allowing the cable 30 to be connected to the photovoltaic terminal 20 and to smoothly insert the connector 100 into the mating components.

[0045] In some embodiments, the insulating housing 10 can be a split structure or a one-piece structure. Taking a split structure as an example, it includes a first housing and a second housing. The first housing and the second housing can be assembled into one piece by means of snaps, threads, or ultrasonic welding to facilitate the installation and subsequent maintenance of internal components. The outer surface of the insulating housing 10 can also be provided with anti-slip textures or operating handles to facilitate insertion and removal operations by construction personnel.

[0046] In this embodiment, the photovoltaic terminal 20 is at least partially disposed inside the insulating housing 10, for realizing the electrical connection between the cable 30 and the docking component. The photovoltaic terminal 20 can be made of a metal material with excellent conductivity, such as copper alloy or tin-plated copper, and has good contact resistance stability and resistance to electrochemical corrosion.

[0047] One end of the photovoltaic terminal 20 is crimped to the conductor portion of the cable 30. This crimping process creates a tight mechanical connection and a low-resistance electrical path between the photovoltaic terminal 20 and the conductor of the cable 30, allowing the connector 100 to withstand the tensile force of the cable 30 while ensuring stable current transmission. The other end of the photovoltaic terminal 20 can be plugged into the corresponding terminal of a mating component. The mating component can be other connectors, photovoltaic module terminals, inverters, combiner boxes, etc., and this embodiment does not limit the specific type.

[0048] The inventors considered that during the operation of the photovoltaic system, Joule heating is generated due to the conductor resistance when current flows through the photovoltaic terminal 20. This is especially true in the crimped area 50, where the photovoltaic terminal 20 and the conductor of the cable 30 form a crimp connection. The contact resistance in this area makes it a region of concentrated heat generation, and the temperature near this area can reflect the overall thermal state of the photovoltaic terminal 20. Therefore, by placing a temperature sensing device 40 in the crimped area 50, thermal coupling is achieved between the temperature sensing device 40 and the photovoltaic terminal 20, enabling accurate acquisition of the true operating temperature of the photovoltaic terminal 20.

[0049] In some embodiments, the crimping area 50 of the photovoltaic terminal 20 can be designed as a cylindrical crimping structure or a slotted crimping structure to adapt to the crimping requirements of cables 30 with different diameters.

[0050] In this embodiment, the temperature detection device 40 is a temperature sensing element of the connector 100, which is disposed in the crimping area 50 between the photovoltaic terminal 20 and the cable 30 and forms thermal coupling with the photovoltaic terminal 20 to collect temperature information of the photovoltaic terminal 20.

[0051] In some embodiments, the temperature sensing device 40 may be a thermistor, thermocouple, digital temperature sensor, or other sensing element with temperature-to-electrical signal conversion function. Taking a thermistor as an example, the resistance value of a thermistor changes with temperature in a definite functional relationship, and the corresponding temperature can be deduced by measuring the resistance value; taking a digital temperature sensor as an example, a digital temperature sensor integrates a temperature sensing element and signal processing circuit, and can directly output a digital temperature value.

[0052] In some embodiments, if the temperature sensing device 40 is a thermistor, the thermistor may also be coated with epoxy resin.

[0053] In this embodiment, by selecting a thermistor as the temperature detection device, the temperature change of the photovoltaic terminal can be quickly sensed, improving the response efficiency and accuracy of temperature detection. The epoxy resin coating on the outside of the thermistor can reduce the interference of impurities such as water vapor and dust in the external environment on the thermistor, improve the working stability of the thermistor, and also form thermal coupling with the photovoltaic terminal, improving the accuracy of temperature detection.

[0054] In related technologies, temperature sensing devices are typically located on the surface of an insulating shell or outside the connector. Heat must be conducted step by step through the insulating shell material, air gaps, and multi-layered structures, resulting in a long heat conduction path and high thermal resistance. This leads to delayed temperature detection and deviations from the actual temperature. This application addresses this by placing the temperature sensing device 40 in the crimping area 50, allowing heat to reach the device 40 only through a very short heat conduction path. This shortens the thermal response time, reduces heat loss during the transfer process, and thus improves the accuracy of temperature detection.

[0055] Thermal coupling between the temperature sensing device 40 and the photovoltaic terminal 20 can be achieved in a variety of ways.

[0056] In some embodiments, the temperature sensing device 40 may be attached to the outer surface of the pressing area 50, and thermal grease or thermal pads may be applied between the temperature sensing device 40 and the pressing area 50 to reduce contact thermal resistance and enhance heat conduction efficiency.

[0057] In some embodiments, the temperature sensing device 40 can be embedded in a pre-set groove or hole in the crimping area 50, so that the temperature sensing surface of the temperature sensing device 40 is in direct contact with the photovoltaic terminal 20 body, further shortening the heat conduction path. The temperature sensing device 40 can also be elastically pressed into the crimping area 50 by a metal spring or clamp structure.

[0058] It should be noted that the temperature sensing device 40 is disposed in the pressing area 50, but this does not mean that the temperature sensing device 40 must be located at the geometric center of the pressing area 50. As long as there is a low thermal resistance heat conduction path between the temperature sensing device 40 and the pressing area 50, the technical requirements for thermal coupling are met.

[0059] In some embodiments, a structural window is provided on the crimping area 50, and the temperature measuring head of the temperature sensing device 40 is located on the outer periphery of the opening of the structural window away from the photovoltaic terminal, or at least partially extends into the interior of the structural window.

[0060] The structural window is a through-hole, groove, or notch structure opened in a local area of ​​the pressing area 50. It can be used to provide operating space for the assembly and positioning of the temperature sensing device 40, or to facilitate observation of the internal state of the pressing area 50 from the outside. The shape of the structural window can be circular, rectangular, or other shapes, and this embodiment of the application does not limit it.

[0061] The temperature sensing head of the temperature sensing device 40 is the part of the device responsible for temperature sensing, and it may include a temperature sensing element. Taking a thermistor as an example, the temperature sensing element may be made of a metal oxide ceramic material with a significant temperature coefficient of resistance. When the temperature changes, the resistance value of the temperature sensing element changes accordingly, and the resistance change can be converted into a temperature reading through a measuring circuit.

[0062] The temperature sensing head of the temperature sensing device 40 is located on the outer periphery of the opening of the structural window away from the photovoltaic terminal 20. This means the temperature sensing head is positioned on the outer edge of the opening on the side of the structural window facing away from the photovoltaic terminal 20 body, with the sensing surface of the head facing the structural window. A heat conduction path is formed between the temperature sensing head and the pressing area 50 through the opening edge of the structural window. This method allows the temperature sensing head to avoid penetrating the solid structure of the pressing area 50, reducing the impact on the mechanical integrity and current-carrying cross-sectional area of ​​the pressing area 50. The temperature sensing head can be fixed to the outer periphery of the opening using a thermally conductive adhesive, or it can be elastically abutted at this position using a snap-fit ​​structure to improve the stability of the thermal contact.

[0063] In some embodiments, the temperature sensing head of the temperature sensing device 40 extends at least partially into the interior of the structural window. This means that the temperature-sensing part at the front end of the temperature sensing head passes through the opening of the structural window and enters the space enclosed by the window, allowing the temperature sensing head to form direct contact or close-range thermal radiation coupling with the inner wall or inner edge of the pressing area 50. This method can shorten the heat conduction distance between the temperature sensing head and the heat source of the pressing area 50, reduce intermediate thermal resistance, and further improve the response speed and accuracy of temperature detection.

[0064] In this embodiment, by setting a structural window in the pressing area and arranging the temperature sensing head of the temperature detection device on the outer periphery of the opening of the structural window away from the photovoltaic terminal or at least partially extending into the structural window, the temperature sensing head can approach the photovoltaic terminal in a low-cost and reliable manner. When the temperature sensing head is set on the outer periphery of the opening, indirect contact measurement is formed between the temperature sensing head and the photovoltaic terminal, reducing the electrical safety risks that may be caused by direct contact. When the temperature sensing head is at least partially extended into the structural window, the heat conduction distance between the temperature sensing head and the photovoltaic terminal is shortened, and the response sensitivity of temperature measurement is improved.

[0065] In some embodiments, there is a gap between the temperature sensing head of the temperature sensing device 40 and the photovoltaic terminal 20, and thermal coupling is achieved through air heat transfer; or, the temperature sensing head of the temperature sensing device 40 is in contact with the photovoltaic terminal 20, and thermal coupling is achieved through solid conduction.

[0066] The gap between the temperature sensing head of the temperature sensing device 40 and the photovoltaic terminal 20 refers to the tiny distance space reserved between the temperature sensing surface of the temperature sensing head and the outer surface of the photovoltaic terminal 20, which can be on the order of millimeters, such as 2mm or 5mm. When the photovoltaic terminal 20 is working, the heat generated diffuses into the surrounding air, and the air in the gap acts as a heat transfer medium to transfer the heat to the temperature sensing head, enabling the temperature sensing head to sense the temperature change of the photovoltaic terminal 20.

[0067] By using air heat transfer, the temperature sensor and the photovoltaic terminal 20 will not be in direct contact. The allowance for tolerance during assembly reduces the requirements for installation accuracy and improves assembly. The reserved gap can reduce mechanical damage or electrochemical corrosion to the surface of the photovoltaic terminal 20 caused by the temperature sensor, and is conducive to forming electrical isolation between the temperature sensor and the charged photovoltaic terminal 20, thereby improving safety.

[0068] In some embodiments, to further improve the stability and efficiency of air heat transfer, a dielectric material with better thermal conductivity than air and electrical insulation properties, such as thermally conductive silicone grease, thermally conductive gel, or phase change thermally conductive material, can be filled in the gap to reduce the equivalent thermal resistance while maintaining electrical isolation.

[0069] In some embodiments, the temperature sensing head of the temperature sensing device 40 is in contact with the photovoltaic terminal 20, and thermal coupling is achieved through solid conduction. Heat is directly conducted to the temperature sensing head via the solid body of the photovoltaic terminal 20. Since the thermal conductivity of solid materials is higher than that of air, the heat conduction path is short and the thermal resistance is low, enabling low-loss heat transfer and allowing the temperature sensing head to accurately reflect the temperature changes of the photovoltaic terminal 20.

[0070] In this embodiment, by using air heat transfer, the gap between the temperature sensor and the photovoltaic terminal forms electrical isolation, reducing the risk of electrical short circuit between the temperature detection device and the photovoltaic terminal and improving the safety of temperature detection. By using solid conduction, the temperature sensor is in direct contact with the photovoltaic terminal, shortening the heat conduction path and reducing heat transfer loss, thereby improving the response speed and detection accuracy of temperature detection.

[0071] In this embodiment, the lead wire 60 is a signal transmission line between the temperature sensing device 40 and the external monitoring circuit. It is electrically connected to the temperature sensing device 40 and is arranged along the direction of the cable 30. It can transmit the temperature signal collected by the temperature sensing device 40 to the temperature monitoring device or control system outside the connector 100.

[0072] The lead wire 60 is arranged along the cable direction and extends to the outside of the connector 100, eliminating the need for an additional dedicated lead wire outlet on the insulating housing 10.

[0073] In some embodiments, the lead wire 60 can be fixed by a heat shrink tubing disposed on the outside of the photovoltaic cable, so that the temperature detection device 40 can be stably positioned close to the photovoltaic terminal 20 without changing the connector structure, without affecting the normal electrical connection and mechanical performance of the cable, and facilitating integration and wiring.

[0074] In some embodiments, the lead wire 60 can also be integrally formed with the insulating sheath of the cable 30 through a co-extrusion process, or the lead wire 60 can be fixed to the outer surface of the cable 30 by means of binding tape, spiral tube, etc. In other embodiments, the lead wire 60 can also be inserted into the gap inside the cable 30, or arranged along the inner side of the shielding layer of the cable 30.

[0075] Lead wire 60 may include insulated wire, the conductor portion of which may be made of copper wire or copper foil, and the insulation layer is made of heat-resistant and aging-resistant insulating material. One end of lead wire 60 is electrically connected to the electrode or pin of temperature sensing device 40 by welding, crimping or plugging, and the other end extends along the cable direction to the outside of connector 100.

[0076] In some embodiments, such as Figure 2 As shown, the other end of the lead wire 60 extends along the cable direction to the outside of the connector 100 and can be connected to the signal connector 70.

[0077] The signal connector 70 is an electrical interface component independent of the connector 100, used to achieve a pluggable electrical connection between the lead-out line 60 and the downstream temperature acquisition circuit. The signal connector 70 can be a wire-to-board connector, a wire-to-wire connector, or other types of connector. Taking a wire-to-board connector as an example, the signal connector 70 includes a wire-end connector connected to the lead-out line 60 and a board-end connector soldered to the circuit board, achieving electrical conduction between the lead-out line 60 and the downstream temperature acquisition circuit through plugging and mating.

[0078] The signal connector 70 can electrically combine the leads 60 from at least two temperature sensing devices 40 and connect them to the back-end temperature acquisition circuit through a unified connection method.

[0079] In a photovoltaic system, connectors 100 can be arranged in strings, with each string including multiple connectors 100 and corresponding photovoltaic terminals 20. Each connector 100 is equipped with a temperature sensing device 40 and a lead wire 60. If each lead wire 60 is individually connected to the back-end temperature acquisition circuit, it will result in a large number of wires, messy wiring, increased system assembly complexity, and increased risk of wiring errors. By integrating the lead wires 60 of multiple temperature sensing devices 40 into the same connector through a signal connector 70, centralized transmission of multiple terminal temperature signals can be achieved, reducing the number of wires.

[0080] In some embodiments, multiple connectors 100 are connected to the same docking component, which is an inverter.

[0081] In this embodiment, by connecting multiple connectors to the same inverter, the temperature signals of each photovoltaic terminal collected by the temperature detection device can be transmitted centrally through the lead wires. The temperature information of each photovoltaic terminal, the loop current information, and the inverter's own operating status information can be fused and analyzed on the same platform, which improves operation and maintenance efficiency.

[0082] According to the connector of this application, by placing the temperature sensing device in the crimping area between the photovoltaic terminal and the cable, and making the temperature sensing device thermally coupled with the photovoltaic terminal, and arranging the lead wire along the cable direction, the normal electrical connection and mechanical performance of the photovoltaic cable are not affected, thereby realizing the integration of the temperature sensing device and the connector. Since the heat does not need to be transferred step by step through multiple layers of insulating thermal conductive layers and conductive paths, the heat conduction path of the heat generated when the photovoltaic terminal is working is shortened, the heat loss in the transfer process is reduced, thereby improving the accuracy of the temperature detection of the photovoltaic terminal.

[0083] This application also provides a method for detecting over-temperature faults in photovoltaic terminals. The execution subject of this method can be an electronic device or a functional module or entity in an electronic device that can implement the method for detecting over-temperature faults in photovoltaic terminals. The electronic devices mentioned in this application include, but are not limited to, inverters, combiner box monitoring units, independent data acquisition devices, or energy management platforms of photovoltaic systems. The following uses an electronic device as the execution subject to illustrate the method for detecting over-temperature faults in photovoltaic terminals provided in this application.

[0084] like Figure 3 As shown, the over-temperature fault detection method for the photovoltaic terminal includes steps 310, 320, 330 and 340.

[0085] Step 310: Obtain the temperature of the photovoltaic terminal transmitted by the temperature detection device in the above connectors through the lead wire, and obtain the loop current of the circuit in which each connector is located.

[0086] In this embodiment, the temperature of the photovoltaic terminal can be acquired by a temperature sensing device in the aforementioned connector and transmitted via a lead wire. The temperature sensing device is located in the crimping area between the photovoltaic terminal and the cable, forming a thermal coupling with the photovoltaic terminal, and can accurately reflect the true temperature of the photovoltaic terminal during operation.

[0087] In some embodiments, the leads of multiple connectors are connected to the same signal connector, and the temperature of the photovoltaic terminal transmitted by the temperature sensing devices in the multiple connectors through the leads includes: The temperature of the photovoltaic terminal is obtained by transmitting the temperature of the temperature sensing devices in the above connectors through the lead wires via the signal connector.

[0088] In this embodiment, the leads of multiple connectors are connected to the same signal connector, which can establish an electrical connection with the signal connector to receive the temperature signals output by each temperature detection device in a polling or concurrent manner, thereby obtaining the temperature data of multiple photovoltaic terminals.

[0089] In this embodiment, by connecting the lead wires of multiple connectors to the same signal connector, the temperature signals of each photovoltaic terminal collected by the temperature detection device can be centrally acquired through the same signal connector, realizing the centralized transmission of multiple terminal temperature signals and reducing the number of signal acquisition channels and wiring complexity.

[0090] In some embodiments, the temperature of the photovoltaic terminals of different connectors may be collected by other devices, the temperature of the photovoltaic terminals of multiple connectors sent by other devices may be obtained, or the temperature of the photovoltaic terminals of different connectors may be received by user input. This application embodiment does not limit this.

[0091] In the embodiments of this application, loop current refers to the current value flowing through the electrical circuit of each connector. Loop current is the direct cause of Joule heating in photovoltaic terminals, resulting in temperature changes.

[0092] In some embodiments, the loop current of each connector can be obtained directly from the inverter, combiner box monitoring unit or current sensor; the loop current can also be collected by Hall current sensor or shunt, but this application embodiment does not limit this.

[0093] It should be noted that the loop current and the temperature of the photovoltaic terminal maintain a time-dependent relationship, meaning that the loop current and the photovoltaic terminal temperature acquired at the same moment belong to the same sampling period.

[0094] In some embodiments, the temperature data of multiple photovoltaic terminals may include the temperature of photovoltaic terminals at different locations in the same connector string, or the temperature of photovoltaic terminals in different strings, different inverters, or different photovoltaic arrays. This application embodiment does not limit this.

[0095] In some embodiments, multiple connectors are connected to the same mating component, which is an inverter.

[0096] In this embodiment, by connecting multiple connectors to the same inverter as docking components, the temperature signals of each photovoltaic terminal collected by the temperature detection device can be transmitted centrally through the lead wires. The temperature information of each photovoltaic terminal, the loop current information, and the inverter's own operating status information can be fused and analyzed on the same platform, which improves operation and maintenance efficiency.

[0097] Step 320: Identify the current-carrying state of the circuit in which each connector is located based on the circuit current.

[0098] In this embodiment, the current-carrying state refers to the range of current levels in the circuit. The current-carrying state can include normal current-carrying state and abnormal current-carrying state. Abnormal current-carrying states include, but are not limited to, no current-carrying state, low current-carrying state, and overloaded current-carrying state.

[0099] Normal current-carrying state refers to the loop current being within the rated operating current range of the photovoltaic system design. Under normal current-carrying state, the heating of the photovoltaic terminals is mainly caused by the conductor resistance and contact resistance under normal operating current, and the temperature change pattern is predictable, allowing for temperature rise comparison analysis based on theoretical calculations. No current-carrying state refers to the loop current being zero or close to zero, such as at night without sunlight, when the module fails and disconnects, or when the loop switch is open. In this case, the photovoltaic terminals show no significant current-induced heating effect, and the temperature approaches ambient temperature. Low current-carrying state refers to the loop current being much lower than the rated operating current. In this case, the Joule heating effect is weak, and the measurement error of the temperature sensing device and fluctuations in ambient temperature have a significant impact on the temperature rise calculation, resulting in low comparability between theoretical and measured temperature rise values. Overload current state refers to the loop current exceeding the rated operating current, which may be caused by module short circuits, inverter failures, or system anomalies. In this case, the abnormal temperature rise may be due to current overload, requiring separate overload protection rather than over-temperature fault diagnosis.

[0100] In some embodiments, the current-carrying state can be identified by comparing the loop current with a preset current threshold. For example, a lower threshold and an upper threshold are set. When the loop current is greater than the lower threshold and less than the upper threshold, it is determined to be a normal current-carrying state; when the loop current is less than or equal to the lower threshold, it is determined to be a low current-carrying or no current-carrying state; when the loop current is greater than or equal to the upper threshold, it is determined to be an overload state. The current threshold can be set according to factors such as the rated current of the photovoltaic module, the current-carrying capacity of the connector, and system operating experience.

[0101] In some embodiments, the current-carrying state of the circuit in which the connector is located can also be identified by combining the loop currents of the positive and negative lines in the same photovoltaic string. For example, if the following conditions are met: and

[0102] If so, it is determined to be a low current carrying capacity; otherwise, it is determined to be a normal current carrying capacity. in, The values ​​represent the lower current threshold. PVA and PVB are the loop currents of the positive and negative lines in the same photovoltaic string, respectively. They can be obtained by sampling the current sensors located on the lines where the connectors of the positive and negative poles of the photovoltaic string are located, or by reporting the current detection circuit and communication interface inside the inverter.

[0103] PVA stands for positive current, which represents the current flowing from the positive terminal of the photovoltaic module through the positive connector to the inverter; PVB stands for negative current, which represents the current flowing from the inverter through the negative connector back to the negative terminal of the photovoltaic module.

[0104] Under normal operating conditions, the positive and negative currents of the same photovoltaic string are equal in value but opposite in direction. The absolute values ​​of PVA and PVB reflect the actual current output intensity of the photovoltaic string.

[0105] Step 330: Under normal current-carrying conditions, calculate the theoretical temperature rise of each photovoltaic terminal based on the current in each circuit, and obtain the measured temperature rise of each photovoltaic terminal based on the temperature of each photovoltaic terminal.

[0106] In this embodiment, the theoretical temperature rise is the expected temperature rise calculated based on the loop current and the electrical parameters of the photovoltaic terminal, reflecting the expected thermal equilibrium temperature of the photovoltaic terminal under normal electrical connection conditions. The theoretical temperature rise can be calculated using Joule's law and the principle of thermal equilibrium.

[0107] Specifically, in the photovoltaic terminal heating power model, the heating power of the photovoltaic terminal is determined by the product of the square of the loop current and the equivalent resistance of the photovoltaic terminal, that is:

[0108] in, Indicates the loop current. This represents the equivalent contact resistance between the photovoltaic terminal and the crimping joint. This indicates the heating power.

[0109] The temperature change of photovoltaic terminals follows a first-order thermal equilibrium equation:

[0110] in, Indicates the temperature of the photovoltaic terminal; Indicates time; It represents the equivalent heat capacity, which characterizes the amount of heat required to raise the temperature of a photovoltaic terminal and adjacent components by a unit, and is related to the photovoltaic terminal material, mass, and structure. It represents the equivalent heat dissipation coefficient, which characterizes the overall ability of a photovoltaic terminal to dissipate heat to the surrounding environment. It is related to the heat dissipation area, surface condition, air velocity, and installation method. This indicates the ambient or housing reference temperature, which is the ambient temperature at the location of the photovoltaic terminal. It can be obtained through an ambient temperature sensor or approximated by the temperature of the photovoltaic terminal under no-current conditions.

[0111] Under steady-state conditions, the terminal temperature no longer changes, that is:

[0112] In this case, the heating power equals the heat dissipation power, and the theoretical temperature rise under steady-state conditions can be obtained. :

[0113] In actual photovoltaic system operation, factors such as changes in sunlight intensity, cloud cover, or adjustments to system operating conditions can cause significant fluctuations in the loop current. These current changes can lead to transient temperature variations at the terminals. If the theoretical temperature rise is calculated directly using a steady-state model, the normal transient temperature rise may be misjudged as an over-temperature fault due to the lag in temperature response.

[0114] Therefore, the heat balance equation can be modified based on the absolute value and rate of change of the current:

[0115] in, This represents an empirical coefficient used to quantify the effect of the rate of change of current on the terminal heating power. The value of can be determined through experimental calibration or fitting of historical data.

[0116] The theoretical temperature rise under steady-state conditions can be obtained. :

[0117] It can be seen that, under the different conditions mentioned above, the theoretical temperature rise value It is the loop current. The function can be represented as:

[0118] In some embodiments, the measured temperature rise can be calculated based on the measured temperature of the photovoltaic terminal collected by the temperature sensing device:

[0119] in, This indicates the measured temperature rise. Indicates photovoltaic terminals i The measured temperature This indicates the reference temperature. The reference temperature can be set according to the actual scenario, such as the initial temperature of the photovoltaic terminal, the ambient temperature, or the reference temperature under low load conditions.

[0120] In some embodiments, the loop current and photovoltaic terminal temperature can be collected synchronously at a fixed sampling period, and the theoretical temperature rise and the measured temperature rise can be calculated in each sampling period. Alternatively, a sliding window process can be applied to the data over a period of time to calculate the theoretical temperature rise and the measured temperature rise, so that the time base of the theoretical temperature rise and the measured temperature rise is the same.

[0121] Step 340: Identify whether the photovoltaic terminal is overheating based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal.

[0122] In this embodiment of the application, the difference between the measured temperature rise and the theoretical temperature rise is... Represented as:

[0123] Assuming the photovoltaic terminal electrical connection is normal and the contact resistance is within the design range, the measured temperature rise should be close to the theoretical temperature rise, with the difference being... The temperature is within a small, normal fluctuation range. However, when the crimping process is poor, the contact surface oxidizes, or long-term operation leads to contact deterioration, the contact resistance increases. Under the same circuit current, the actual heat generation power is higher than the theoretically calculated value, resulting in a higher measured temperature rise than the theoretical temperature rise. The difference is [not specified in the original text]. Exceeding the preset threshold This indicates that the photovoltaic terminal may be at risk of overheating failure.

[0124] In photovoltaic (PV) systems, multiple PV terminals within the same PV string or inverter are typically under similar environmental and illumination conditions, resulting in a consistent temperature distribution. If the temperature of a particular PV terminal is significantly higher than that of the others in the same string, it indicates a localized over-temperature fault. This is further analyzed by considering the difference between the measured and theoretical temperature rise values. If the temperature exceeds the preset threshold, an over-temperature fault can be identified.

[0125] In some embodiments, when an over-temperature fault is detected in the photovoltaic terminal, corresponding protection actions can be triggered, such as sending a control command to the inverter, executing power transistor blocking to cut off or limit the photovoltaic circuit current, or controlling the circuit tripping device to disconnect the faulty branch, thereby reducing safety hazards such as burning and fire caused by continuous over-temperature of the photovoltaic terminal.

[0126] In some embodiments, when an over-temperature fault is detected in the photovoltaic terminal, a prompt message can be output to notify the operation and maintenance personnel or the upper-level management system of the fault status, facilitating timely handling measures. The prompt message can be a local audible and visual alarm signal, such as a flashing red indicator light to indicate an over-temperature fault, or an intermittent buzzer to alert the operation and maintenance personnel. The prompt message can also be a remote communication message, a human-machine interface display, etc., and this application embodiment does not limit the specific type of message.

[0127] According to the photovoltaic terminal over-temperature fault detection method of this application, the temperatures of multiple photovoltaic terminals are acquired, and the loop current is acquired to identify the current-carrying state. Under the condition of normal current carrying, the theoretical temperature rise value is calculated based on the loop current and the measured temperature rise value is calculated based on the measured temperature. Since the theoretical temperature rise value reflects the expected thermal equilibrium temperature of the photovoltaic terminal under normal electrical connection state, and the measured temperature rise value reflects the actual thermal state of the photovoltaic terminal, the difference between the measured temperature rise value and the theoretical temperature rise value can assess whether the photovoltaic terminal has over-temperature. Furthermore, by comparing the temperature differences between each photovoltaic terminal, the influence of external factors such as changes in ambient temperature, illumination, system operating conditions, and temperature detection device failure can be distinguished, thereby improving the accuracy of photovoltaic terminal over-temperature fault detection.

[0128] In some embodiments, the method further includes: When the current-carrying state is low current-carrying state or no current-carrying state, if there is a photovoltaic terminal with a temperature greater than or equal to the first temperature threshold, at least one of the following is obtained: the temperature change rate of each photovoltaic terminal, the current change rate of the circuit it is in, and the temperature difference between it and other photovoltaic terminals. If the temperature change rate is greater than the first change rate threshold and the current change rate is less than or equal to the second change rate threshold, and / or the temperature difference is greater than the second temperature threshold, it is determined that there is an abnormality in the temperature detection device.

[0129] In this embodiment, the current-carrying state is a low-current-carrying state or an empty-current-carrying state, with no effective current flowing through the photovoltaic terminals or extremely low current. Under normal circumstances, the Joule heating effect is negligible, and the photovoltaic terminal temperature should be close to the ambient temperature or a reference temperature, with consistent temperature distribution across all photovoltaic terminals. In this case, if any photovoltaic terminal has a temperature greater than or equal to a first temperature threshold, it indicates a possible temperature anomaly caused by non-current factors, requiring further identification to determine if a temperature detection device malfunctions. The first temperature threshold can be the ambient temperature plus a certain offset, the upper limit of historical ambient temperature statistics, or other values; this embodiment does not limit the specific value.

[0130] It can obtain at least one of the following parameters: the temperature change rate of each photovoltaic terminal, the current change rate of the circuit it is in, and the temperature difference between it and other photovoltaic terminals.

[0131] A malfunction in the temperature sensing device is determined if any of the following conditions are met.

[0132] Condition one: and

[0133] Condition two:

[0134] in, Indicates the rate of temperature change. This represents the first rate of change threshold. Indicates the rate of change of current. The second rate of change threshold can be 0 or a value close to 0, such as approximately equal to 0, 0.1, 0.01, 0.001, etc. The embodiments of this application do not limit this. and Indicates adjacent photovoltaic modules and temperature, This indicates the second temperature threshold.

[0135] The temperature detection device corresponding to a photovoltaic terminal that meets any of the above conditions can be identified as a temperature detection device with an abnormality.

[0136] In some embodiments, when a malfunction of the temperature detection device is detected, a prompt message can be output to notify maintenance personnel or the upper-level management system of the fault status, facilitating timely handling measures. The prompt message can be a local audible and visual alarm signal, such as a flashing yellow indicator light to indicate a malfunction of the temperature detection device, or an intermittent buzzer to alert maintenance personnel. The prompt message can also be a remote communication message, a human-machine interface display, etc., and this application embodiment does not limit the specific type of message.

[0137] In this embodiment, the temperature detection device is diagnosed for anomalies when the current carrying state is low or no current carrying state. Since the theoretical heat generation of the photovoltaic terminal is low when the current carrying state is low or no current carrying state, the temperature should be close to the ambient temperature or in a low state. Therefore, when a photovoltaic terminal with a temperature greater than or equal to the first temperature threshold is detected, the temperature change rate, current change rate and temperature difference with other photovoltaic terminals are further obtained. When the temperature change rate is greater than the first change rate threshold and the current change rate is less than or equal to the second change rate threshold, it indicates that the temperature rise trend is unrelated to the electrical load, and the temperature rise caused by load fluctuation is ruled out. If the temperature difference with other photovoltaic terminals is greater than the second temperature threshold, it is confirmed that the abnormal temperature rise is a local anomaly, so it can be confirmed that it is a fault of the temperature detection device itself, rather than an over-temperature fault, thus reducing the risk of false alarms in the judgment of over-temperature faults.

[0138] In some embodiments, identifying whether a photovoltaic terminal has an over-temperature fault based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal, includes: If the difference between the measured temperature rise and the theoretical temperature rise is greater than the third temperature threshold and the duration is greater than or equal to the target duration threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, an over-temperature fault is determined to exist.

[0139] In this embodiment, the third temperature threshold can be a certain percentage of the theoretical temperature rise or a fixed temperature value, such as 5°C, 10°C or other values.

[0140] Considering that a brief period of excessively high measured temperature rise may be caused by sudden current changes, measurement noise, or environmental disturbances, as the thermal equilibrium process progresses, the measured temperature rise will gradually approach the theoretical expected value. However, an over-temperature fault will cause the measured temperature rise to continuously deviate from the theoretical expected value and will not recover in a short period of time.

[0141] Therefore, if the difference greater than the third temperature threshold If the duration is greater than or equal to the target duration threshold, it indicates a possible over-temperature fault. The target duration threshold can be 2 minutes, 5 minutes, or other values.

[0142] In this embodiment, in order to further identify whether the abnormal temperature rise is due to an overheating fault of the photovoltaic terminal or an overall temperature rise caused by factors such as changes in ambient temperature and uneven sunlight, it is necessary to further determine the temperature distribution of multiple photovoltaic terminals.

[0143] Specifically, the temperature difference between each photovoltaic terminal can be calculated:

[0144] in, and These represent photovoltaic terminals. and temperature, Indicates photovoltaic terminals and The difference between temperatures.

[0145] Under normal circumstances, the temperature distribution of multiple photovoltaic terminals is consistent:

[0146] in, Indicates the normal temperature threshold; If the following occurs:

[0147] This indicates that the temperature distribution is not consistent.

[0148] In some embodiments, a fourth temperature threshold may be set, which may be greater than... The value, for example, greater than 5℃, 10℃ or other values, in When the temperature is greater than or equal to the fourth temperature threshold, it is determined that the temperature distribution does not conform to the consistency.

[0149] In this embodiment, if there are at least a group of photovoltaic terminals whose temperature difference is greater than or equal to the fourth temperature threshold, it indicates that the temperature distribution is not consistent and the abnormal temperature rise is not caused by factors such as changes in ambient temperature or uneven sunlight. Therefore, it can be determined that there is an over-temperature fault. Photovoltaic terminals whose difference between the measured temperature rise and the theoretical temperature rise is greater than the third temperature threshold can be identified as photovoltaic terminals with an over-temperature fault.

[0150] In this embodiment, since the difference between the measured temperature rise and the theoretical temperature rise reflects the deviation of the actual thermal state of the photovoltaic terminal from the expected thermal state, if the deviation persists for a certain period of time, it eliminates the possibility of transient temperature rise fluctuations caused by instantaneous current surges or measurement noise. If the temperature difference between at least one group of photovoltaic terminals is greater than or equal to the fourth temperature threshold, it further indicates that the temperature distribution of multiple photovoltaic terminals does not conform to the consistency characteristics. The abnormal temperature rise is a photovoltaic terminal over-temperature fault rather than an overall temperature rise caused by factors such as changes in ambient temperature or uneven sunlight. This improves the accuracy and anti-interference ability of photovoltaic terminal over-temperature fault detection and reduces the risk of false alarms caused by operating condition fluctuations or environmental factors.

[0151] In some embodiments, the method further includes: If the difference between the measured temperature rise and the theoretical temperature rise is less than or equal to the third temperature threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, it is determined that there is an abnormality in the temperature detection device.

[0152] In this embodiment, if the difference Less than or equal to the third temperature threshold or difference greater than the third temperature threshold If the duration is less than the target duration threshold, it indicates that the thermal state of the photovoltaic terminal is within the normal range.

[0153] If the thermal state of the photovoltaic (PV) terminals is within the normal range, then the temperature distribution of multiple PV terminals under the same electrical environment should be consistent. If the temperature difference between at least one group of PV terminals is greater than or equal to the fourth temperature threshold, it indicates that the temperature distribution of multiple PV terminals is inconsistent, which contradicts the fact that the thermal state of the PV terminals is within the normal range. Therefore, it can be determined that the cause is more likely a malfunction in the temperature detection device. Alert messages can be generated and displayed to maintenance personnel through local alarms, remote messages, or human-machine interfaces.

[0154] In this embodiment, since the difference between the measured temperature rise and the theoretical temperature rise is within the normal range, it indicates that the expected thermal state calculated based on the electrical load is consistent with the actual thermal state, and the photovoltaic terminal itself does not have an over-temperature fault. In this case, if the temperature difference between at least one group of photovoltaic terminals is too large, it indicates that the temperature distribution of multiple photovoltaic terminals does not conform to the consistency characteristics. Therefore, it can be concluded that the local temperature difference is caused by the measurement abnormality of the temperature detection device itself, which reduces the risk of false alarm in the judgment of over-temperature fault.

[0155] The following scenario illustrates the over-temperature fault detection process of the photovoltaic terminal in this embodiment of the application. For example... Figure 4 As shown, it includes the following steps.

[0156] S1: Data Acquisition.

[0157] In this step, the loop current and the temperature of the photovoltaic terminals can be collected within a preset sampling period. The loop current includes: the loop current PVA of the positive terminal and the loop current PVB of the negative terminal; the temperature of the photovoltaic terminals is measured by the temperature sensing devices corresponding to each connector. Temperature: T1, T2, T3, T4. Ambient temperature or reference temperature: .

[0158] S2: Current status judgment.

[0159] The current-carrying state of the circuit in which the connector is located is identified based on the circuit current. If the following conditions are met: and

[0160] If the current is low, proceed to S3; otherwise, proceed to S4. This indicates the lower limit threshold of the current.

[0161] S3: Low current carrying capacity judgment.

[0162] This step is used to filter out false alarms related to over-temperature faults. Specifically, it checks whether the photovoltaic terminal temperature has abnormally increased when the current-carrying state of the circuit containing the connector is low or no current-carrying. If the following conditions are met:

[0163] If the condition is determined to be normal, return to S1.

[0164] If the following conditions are met:

[0165] If the condition is flagged as a suspected malfunction of the temperature sensing device, proceed to step S7. This indicates the first temperature threshold.

[0166] S4: Calculation of theoretical temperature rise.

[0167] Assuming the current-carrying state of the circuit where the connector is located is under normal current-carrying conditions, the theoretical temperature rise of the photovoltaic terminal is calculated based on the collected circuit current:

[0168] S5: Comparison of measured temperature rise values.

[0169] Based on the data collected by each temperature sensing device, the measured temperature rise of the corresponding photovoltaic terminal is calculated:

[0170] in, This indicates the measured temperature rise. Indicates photovoltaic terminals i The measured temperature Indicates the reference temperature.

[0171] The measured temperature rise was compared with the theoretical temperature rise.

[0172] S6: Over-temperature fault detection.

[0173] Determine if the temperature distribution of multiple photovoltaic terminals is consistent. The temperature difference between each photovoltaic terminal can be calculated.

[0174] in, and These represent photovoltaic terminals. and temperature, Indicates photovoltaic terminals and The difference between temperatures.

[0175] Under normal circumstances, the temperature distribution of multiple photovoltaic terminals is consistent:

[0176] in, Indicates the normal temperature threshold; If the following occurs:

[0177] This indicates that the temperature distribution is not consistent.

[0178] If the temperature distribution is not uniform, it must meet the following conditions:

[0179] and The duration exceeds the preset time threshold If an over-temperature fault is detected, corresponding protection actions can be triggered, such as sending control commands to the inverter, executing power transistor blocking to cut off or limit the photovoltaic circuit current, or controlling the circuit tripping device to disconnect the faulty branch, thereby reducing safety hazards such as burning and fire caused by continuous over-temperature of the photovoltaic terminals.

[0180] Otherwise, proceed to S8.

[0181] S7: Temperature detection device malfunction determination.

[0182] A malfunction in the temperature sensing device is determined if any of the following conditions are met.

[0183] Condition one: and

[0184] Condition two:

[0185] in, Indicates the rate of temperature change. This represents the first rate of change threshold. Indicates the rate of change of current. and Indicates adjacent photovoltaic modules and temperature, This indicates the second temperature threshold.

[0186] The temperature detection device corresponding to a photovoltaic terminal that meets any of the above conditions can be identified as a temperature detection device with an abnormality.

[0187] When a malfunction in the temperature detection device is detected, a prompt message can be output to notify maintenance personnel or the upper-level management system of the fault status, facilitating timely handling. The prompt message can be a local audible and visual alarm signal, such as a flashing yellow indicator light to indicate a malfunction in the temperature detection device, or an intermittent buzzer to alert maintenance personnel. The prompt message can also be a remote communication message, a human-machine interface display, etc., and this embodiment does not limit the specific type of message.

[0188] S8: False alarm elimination judgment.

[0189] If the deviation between the measured temperature rise and the theoretical temperature rise is within the normal range, and the temperature distribution of multiple photovoltaic terminals is consistent, then it is determined to be a non-fault state, i.e., false alarm is eliminated; if the deviation between the measured temperature rise and the theoretical temperature rise is within the normal range, and the temperature distribution of multiple photovoltaic terminals is not consistent, then the cause is more likely to be an abnormality of the temperature detection device, generating a prompt message, and notifying the operation and maintenance personnel through local alarms, remote messages, or human-machine interface display.

[0190] The over-temperature fault detection method for photovoltaic terminals provided in this application can be executed by an over-temperature fault detection device for photovoltaic terminals. This application uses an over-temperature fault detection device for photovoltaic terminals executing the over-temperature fault detection method as an example to illustrate the over-temperature fault detection device for photovoltaic terminals provided in this application.

[0191] This application also provides an over-temperature fault detection device for photovoltaic terminals.

[0192] like Figure 5 As shown, the over-temperature fault detection device for the photovoltaic terminal includes: The first acquisition module 510 is used to acquire the temperature of the photovoltaic terminal transmitted by the temperature detection device in the multiple connectors through the lead wire, and to acquire the loop current of the circuit in which each connector is located. The first identification module 520 is used to identify the current-carrying state of the circuit in which each connector is located based on the circuit current. The second acquisition module 530 is used to calculate the theoretical temperature rise of each photovoltaic terminal based on the current of each circuit when the current carrying state is normal, and to obtain the measured temperature rise of each photovoltaic terminal based on the temperature of each photovoltaic terminal. The second identification module 540 is used to identify whether the photovoltaic terminal is overheating based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal.

[0193] According to the photovoltaic terminal over-temperature fault detection device of this application, the temperature of multiple photovoltaic terminals is acquired, and the loop current is acquired to identify the current carrying state. Under the condition of normal current carrying, the theoretical temperature rise value is calculated based on the loop current and the measured temperature rise value is calculated based on the measured temperature. Since the theoretical temperature rise value reflects the expected thermal equilibrium temperature of the photovoltaic terminal under normal electrical connection state, and the measured temperature rise value reflects the actual thermal state of the photovoltaic terminal, the difference between the measured temperature rise value and the theoretical temperature rise value can assess whether the photovoltaic terminal has over-temperature. Furthermore, by comparing the temperature differences between each photovoltaic terminal, the influence of external factors such as changes in ambient temperature, illumination, system operating conditions, and temperature detection device failure can be distinguished, thereby improving the accuracy of photovoltaic terminal over-temperature fault detection.

[0194] like Figure 6 As shown, this application embodiment also provides an electronic device 600, including a processor 601, a memory 602, and a computer program stored in the memory 602 and executable on the processor 601. When the program is executed by the processor 601, it implements the various processes of the above-described photovoltaic terminal over-temperature fault detection method embodiment and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0195] This application also provides a non-transitory computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various processes of the above-described photovoltaic terminal over-temperature fault detection method embodiment and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0196] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0197] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-mentioned over-temperature fault detection method for photovoltaic terminals.

[0198] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0199] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface and the processor are coupled. The processor is used to run programs or instructions to implement the various processes of the above-described photovoltaic terminal over-temperature fault detection method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0200] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0201] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0202] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0203] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

[0204] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0205] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A connector, characterized in that, include: Insulating outer casing; Photovoltaic terminals, at least partially disposed inside the insulating housing, are used to achieve electrical connection between the cable and the docking component; A temperature sensing device is disposed in the crimping area between the photovoltaic terminal and the cable, and is thermally coupled to the photovoltaic terminal to collect the temperature of the photovoltaic terminal; A lead wire, electrically connected to the temperature sensing device, is arranged along the direction of the cable and is used to transmit the temperature.

2. The connector according to claim 1, characterized in that, The temperature sensing device is a thermistor, and the thermistor is coated with epoxy resin.

3. The connector according to claim 1, characterized in that, The pressing area is provided with a structural window, and the temperature measuring head of the temperature detection device is located on the outer periphery of the opening of the structural window away from the photovoltaic terminal, or at least partially extends into the interior of the structural window.

4. The connector according to claim 1, characterized in that, The temperature sensing device has a gap between its temperature sensing head and the photovoltaic terminal, and thermal coupling is achieved through air heat transfer; alternatively, the temperature sensing head of the temperature sensing device is in contact with the photovoltaic terminal, and thermal coupling is achieved through solid conduction.

5. The connector according to claim 1, characterized in that, Multiple connectors are connected to the same docking component, which is an inverter.

6. A method for detecting over-temperature faults in photovoltaic terminals, characterized in that, include: The temperature of the photovoltaic terminal transmitted by the temperature sensing device in the connector as described in any one of claims 1-5 through the lead wire is obtained, and the loop current of the circuit in which each connector is located is obtained. The current-carrying state of each connector in the circuit is identified based on the circuit current; When the current-carrying state is normal, the theoretical temperature rise of each photovoltaic terminal is calculated based on the current of each circuit, and the measured temperature rise of each photovoltaic terminal is obtained based on the temperature of each photovoltaic terminal. The difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal, are used to identify whether the photovoltaic terminal is overheating.

7. The method according to claim 6, characterized in that, The leads of multiple connectors are connected to the same signal connector, and the step of obtaining the temperature of the photovoltaic terminal transmitted by the temperature sensing device in the multiple connectors as described in any one of claims 1-5 through the leads includes: The temperature of the photovoltaic terminal is obtained through the signal connector by means of the temperature sensing device in the connector as described in any one of claims 1-5, transmitted via the lead wire.

8. The method according to claim 6, characterized in that, The method further includes: When the current-carrying state is a low current-carrying state or an empty current-carrying state, if there is a photovoltaic terminal with a temperature greater than or equal to a first temperature threshold, at least one of the following is obtained: the temperature change rate of each photovoltaic terminal, the current change rate of the circuit it is in, and the temperature difference between each photovoltaic terminal and other photovoltaic terminals. If the temperature change rate is greater than a first change rate threshold and the current change rate is less than or equal to a second change rate threshold, and / or the temperature difference is greater than a second temperature threshold, it is determined that there is an abnormality in the temperature detection device.

9. The method according to claim 6, characterized in that, The step of identifying whether a photovoltaic terminal has an over-temperature fault based on the difference between the measured temperature rise and the theoretical temperature rise, and the difference between the temperatures of each photovoltaic terminal, includes: If the difference between the measured temperature rise and the theoretical temperature rise is greater than the third temperature threshold and the duration is greater than or equal to the target duration threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, an over-temperature fault is determined to exist.

10. The method according to claim 9, characterized in that, The method further includes: If the difference between the measured temperature rise and the theoretical temperature rise is less than or equal to the third temperature threshold, and if the difference between the temperatures of at least one set of photovoltaic terminals is greater than or equal to the fourth temperature threshold, it is determined that there is an abnormality in the temperature detection device.

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