Leakage protection type charger and monitoring method
By combining a dual-core leakage detection module and a temperature and humidity sensor, the problem of incomplete leakage detection in mobile phone chargers in humid environments is solved, enabling stable fixation of different charging heads and remote alarms, thus improving the safety and convenience of the charger.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN KUNXING TECH CO LTD
- Filing Date
- 2026-03-13
- Publication Date
- 2026-06-05
Smart Images
Figure CN122159447A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of leakage protection technology for mobile phone chargers, and in particular to a leakage protection charger and a monitoring method thereof. Background Technology
[0002] As one of the most frequently used electronic devices in daily life, the safety of mobile phone chargers is directly related to the personal safety of users. Currently, mobile phone charging mainly uses a combination of a switching power supply charger and a charging cable. The charger is directly plugged into a power outlet, converting 220V AC power into 5V or higher DC power to charge the phone battery. Existing mobile phone chargers lack a separate leakage protection device, and there is a lack of leakage protection devices suitable for various mobile phone chargers. The main shortcomings are as follows: First, the leakage current detection capability is incomplete, resulting in protection blind spots. Traditional leakage protection devices mostly use single-core zero-sequence current transformers, which can only detect AC leakage signals. However, with the widespread adoption of fast charging technology for mobile phones, the internal circuit topology of chargers has become increasingly complex, with numerous rectifier and filter circuits and power factor correction circuits in the switching power supply circuit. When the internal insulation of the charger fails or becomes damp, the resulting leakage current not only contains AC components but also pulsating DC or even smooth DC components. When faced with the DC component, the traditional single-core leakage current detection scheme will experience pre-saturation of the core, causing the protector to fail to trip properly when a real AC leakage occurs, creating a safety hazard of "the protector is still there, but the protection function has failed." Secondly, there is a lack of perception and comprehensive judgment capabilities regarding the humidity of the charging environment. Mobile phone chargers are often exposed to humid environments such as bathrooms, kitchens, and outdoors during use. Excessive humidity significantly reduces the insulation resistance between internal components, increasing the risk of leakage. Existing leakage protection devices rely solely on a single leakage current threshold for judgment, directly cutting off the power when the detected leakage current exceeds the threshold. This judgment method does not consider the cumulative effect of environmental humidity on leakage risk, cannot provide early warnings in cases of minor leakage but extremely high humidity, and cannot distinguish between temporary leakage caused by moisture and permanent leakage caused by equipment failure, easily leading to false alarms or delayed protection. Third, existing leakage protection devices are not suitable for mobile phone charging heads, and there is a lack of reliable fixing structures for charging heads of different sizes. Summary of the Invention
[0003] The purpose of this invention is to provide a leakage protection charger and monitoring method to solve the problems of existing mobile phone chargers lacking leakage detection capability, charging environment humidity sensing capability, and leakage protection device for reliably fixing mobile phone chargers of different sizes.
[0004] To achieve the above objectives, the present invention provides a leakage current protection charger. A leakage current protection device is installed on the mobile phone charger head. The leakage current protection device includes an insulating shell, on which are provided an output socket for inserting two prongs of the mobile phone charger head and an input pin for charging when plugged into a socket. The live wire and neutral wire connected to the input pin pass through a leakage current detection unit and are connected to the output socket via a power-off unit. The leakage current detection unit is connected to a control unit, which is connected to an environmental sensing unit for monitoring the air humidity of the mobile phone charger head's operating environment. The leakage current detection unit includes a dual-core leakage current detection module, which is connected to the control unit via a signal conditioning circuit one and a signal conditioning circuit two. The insulating shell is provided with a rigid clamping and elastic locking mechanism for fixing the mobile phone charger head.
[0005] Preferably, the control unit, environmental sensing unit, leakage detection unit, power-off unit, and output jack are located inside the insulating housing.
[0006] Preferably, the input pins include a live wire input pin, a neutral wire input pin, and a protective ground pin. The live wire input pin and the neutral wire input pin are respectively connected to one end of the live wire and one end of the neutral wire. The output jacks include a live wire output jack and a neutral wire output jack. The power-off unit includes relay one and relay two. The other end of the live wire and the other end of the neutral wire are respectively connected to the live wire output jack and the neutral wire output jack through relay one and relay two. The protective ground pin is connected to the protective ground wire.
[0007] Preferably, the control unit includes an MCU, a low-voltage gallium nitride switching power supply, and a Bluetooth module, the Bluetooth module being used to connect to a mobile terminal for data transmission; The power-off unit also includes a relay drive circuit, through which the MCU controls the on / off state of relay one and relay two respectively.
[0008] Preferably, the dual-core leakage current detection module includes an upper core and a lower core arranged in parallel and coaxially. The live wire and neutral wire connected to the input pin pass through the center of the upper core and the lower core. A physical gap is left between the upper core and the lower core. The upper core is used to detect AC and pulsating DC leakage current, and the lower core is used to detect smooth DC leakage current. A set of secondary windings is wound on the upper core. One end of the secondary windings is grounded, and the other end of the secondary windings is connected to the input terminal of the signal conditioning circuit. The output terminal of the signal conditioning circuit is connected to the MCU. The lower magnetic core is wound with two sets of coils: an excitation winding and a detection winding. One end of the excitation winding is connected to the output of the push-pull drive circuit, and the input of the push-pull drive circuit is connected to the MCU. The other end of the excitation winding is grounded. One end of the detection winding is connected to the input of the second signal conditioning circuit, and the output of the second signal conditioning circuit is connected to the MCU. The other end of the detection winding is grounded.
[0009] Preferably, the environmental sensing unit includes a temperature and humidity sensor, a grounding detection circuit, and a reset button. The temperature and humidity sensor is connected to the MCU and is used to monitor the humidity of the environment. The temperature and humidity sensor is located above the output socket inside the insulating housing. A miniature ventilation hole communicating with the outside is opened on the inner wall of the insulating housing directly opposite the temperature and humidity sensor.
[0010] Preferably, one end of the reset button is connected to the MCU and the other end is grounded. The input terminal of the low-voltage gallium nitride switching power supply is connected to the live wire and the neutral wire. The output terminal of the low-voltage gallium nitride switching power supply is connected to the relay drive circuit, the push-pull drive circuit, the first signal conditioning circuit, the second signal conditioning circuit, the MCU, the Bluetooth module, and the temperature and humidity sensor. The grounding detection circuit is connected to the neutral wire, protective ground wire, and MCU respectively.
[0011] Preferably, the rigid clamping and elastic locking coordinating mechanism includes a rigid clamping structure and an elastic locking structure. The rigid clamping structure includes a top plate and a bottom plate respectively disposed at the top and bottom of the insulating shell. A sliding post 1 is slidably disposed on the top plate, and a pull handle is disposed at the top of the sliding post 1. The bottom end of the sliding post 2 passes through the insulating shell and connects to the top of the clamping plate 1. Side plates 1 are disposed on both sides of the clamping plate 1. A sliding post 2 is slidably disposed on the bottom plate, and a limit block is disposed at the bottom of the sliding post 2. The top end of the sliding post 2 passes through the bottom plate and connects to the bottom of the clamping plate 2. Side plates 2 are symmetrically disposed on both sides of the clamping plate 2. 2. A sliding groove is provided inside the side plate 1. The top of the side plate 2 is inserted into the sliding groove and slidably connected to the sliding groove. Several gear sets are evenly arranged on both sides of the side plate 2 from bottom to top. The gear sets include gear 1 and gear 2 that are meshed together. Gear 1 and gear 2 are rotatably connected to the side plate 2 through rotating shafts. A rack that is adapted to gear 1 and gear 2 is provided in the sliding groove. Gear 1 and gear 2 are meshed with the rack respectively. Spring 1 and spring 2 are respectively sleeved on sliding column 1 and sliding column 2. Spring 1 is located between the top plate and clamping plate 1, and spring 2 is located between the bottom plate and clamping plate 2.
[0012] Preferably, the elastic locking structure includes elastic ropes symmetrically arranged on both sides of the insulating shell, both ends of which are fixed to the rotating sleeve. A fixing post is provided inside the rotating sleeve, the fixing post is inserted into the rotating sleeve and rotatably connected to the rotating sleeve, and the fixing post is respectively provided on the top plate and the bottom plate.
[0013] The present invention discloses a monitoring method for a leakage current protected charger, comprising the following steps: Step 1, Preparing for charging: Pull the handle to open, and sliding column one will cause the top plate and side plate one to rise. Side plate two, inside side plate one, will descend as side plate one rises through a gear set and rack. Insert the two prongs of the mobile phone charger into the output socket of the leakage protection device. Release the handle to open, and under the action of spring one and spring two, top plate one will descend and top plate two will rise to clamp the mobile phone charger. Insert the input pin of the leakage protection device into the target socket, insert one end of the charging cable into the mobile phone charger, and pull the elastic ropes on both sides of the leakage protection device. The elastic ropes are interlaced and fixed to the end of the charging cable connected to the mobile phone charger. Finally, connect the other end of the charging cable to the mobile phone to charge. Step 2, Real-time Leakage Detection: AC and pulsating DC leakage detection: The upper magnetic core senses the vector sum of the currents of the live wire and the neutral wire in real time. When AC or pulsating DC leakage occurs, the secondary winding of the upper magnetic core generates an induced signal. This induced signal is filtered and amplified by the signal conditioning circuit and then transmitted to the MCU. Smooth DC leakage detection: The MCU timing control push-pull drive circuit outputs an excitation signal to the excitation winding of the lower magnetic core, so that the lower magnetic core is in an alternating saturation working state; when there is a smooth DC leakage between the live wire and the neutral wire, the detection winding of the lower magnetic core induces a voltage signal containing leakage current information, which is processed by the signal conditioning circuit two and then transmitted to the MCU. Step 3, Leakage current determination and graded response: The MCU makes a comprehensive judgment based on the leakage current signal received after processing in step two, combined with the ambient humidity data monitored by the temperature and humidity sensor: Determining minor leakage: If the detected leakage current value is lower than or equal to the preset safety action threshold of 10mA and the ambient humidity is high, the MCU determines it to be a high-risk state and sends a "humid environment, minor leakage exists, please pay attention to safety" prompt message to the mobile terminal via Bluetooth module; Determining severe leakage: If the detected leakage current value exceeds the preset safety action threshold of 10mA, the MCU will immediately determine it as a severe leakage fault; Step 5, Fault Protection and Remote Alarm: After a serious leakage fault is determined, the MCU immediately performs a local power cut-off. The MCU instantly cuts off relay one and relay two through the relay drive circuit, disconnecting the output path between the live wire and the neutral wire, and forcing the mobile phone charger to stop working. At the same time, the MCU packages the leakage type, leakage current amplitude, trigger time, and ambient humidity data at the time of triggering, and sends them to the connected mobile terminal via Bluetooth module to inform the user that "the charger has triggered leakage protection and cut off the power", reminding the user to check the charging equipment or line. Step Six: Manual Reset and Troubleshooting After the leakage protection trips, the circuit remains disconnected. After ruling out faults in the phone charger, charging cable, or socket, the user can manually press the reset button on the insulating housing to send a reset signal to the MCU. Upon receiving the reset signal, the MCU first uses the leakage detection unit to re-detect whether there is a leakage fault in the circuit. If no leakage is detected and the ambient humidity has dropped to a safe range, the MCU controls the relay drive circuit to re-engage relay one and relay two, restoring power supply. If the fault exists, the power is kept off and an alarm message is sent to the mobile terminal again.
[0014] The advantages and positive effects of the leakage protection charger and monitoring method described in this invention are: 1. This invention employs a dual-core leakage current detection module consisting of a parallel and coaxially arranged upper and lower magnetic core. The upper magnetic core, in conjunction with the secondary winding and signal conditioning circuit one, can accurately detect AC leakage current and pulsating DC leakage current. The lower magnetic core is excited by a push-pull drive circuit and detects smooth DC leakage current based on the fluxgate principle. The induced signal is then processed by signal conditioning circuit two and input to the MCU. This invention overcomes the shortcomings of traditional single-core zero-sequence current transformers, which can only detect AC leakage current and whose protection fails due to core pre-saturation when facing DC components. It achieves accurate capture and identification of all types of leakage current signals, including AC, pulsating DC, and smooth DC, thereby improving the safety protection capability of the charger under various complex circuit conditions. 2. This invention, by setting a temperature and humidity sensor inside the insulating shell, monitors the air humidity of the charger's working environment in real time, and makes a comprehensive judgment based on leakage detection data, and performs graded responses, provides early warning of safety hazards under minor leakage, and achieves full coverage from early warning to protection, improving the adaptability and reliability of mobile phone chargers in humid environments such as bathrooms and kitchens. 3. The rigid clamping structure, through the linkage mechanism of top plate, bottom plate, sliding column, clamping plate, spring and gear rack, can automatically adapt to the thickness differences of different brands of mobile phone charging heads; the elastic locking structure uses elastic ropes on both sides of the insulating shell, which can be intertwined and fixed at the connection end of the charging cable and the charging head, effectively preventing loosening caused by accidental pulling; it is easy to operate, which can not only firmly fix the charging head body, but also provide elastic locking at the connection end of the charging cable, solving the problem of poor compatibility and unstable connection between leakage protection device and mobile phone charging head, and greatly improving the tensile strength and contact reliability during the charging process; 4. The control unit integrates a Bluetooth module to communicate with the mobile terminal in real time, enabling the transmission of data such as leakage type, leakage current amplitude, trigger time, and ambient humidity at the time of triggering to the mobile terminal. This allows users to promptly obtain fault details, accurately determine the cause of the fault, and avoid blindly resetting the device. 5. The invention integrates the leakage current detection unit, control unit, environmental sensing unit, power-off unit, and output jack into an insulating housing, making it compact, portable, and easy to use. The rigid clamping and elastic locking mechanism requires no tools; users can simply pull the handle and wrap the elastic rope to complete the installation and fixation, making it convenient and suitable for various user groups. At the same time, the introduction of a low-voltage gallium nitride switching power supply improves power conversion efficiency, reduces power consumption, and further enhances the overall performance of the product.
[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a leakage protection charger according to the present invention; Figure 2 This is a front view of an embodiment of a leakage protection charger according to the present invention; Figure 3 This is a side view of an embodiment of a leakage protection charger according to the present invention; Figure 4 This is a circuit interaction framework diagram of an embodiment of a leakage current protection charger monitoring method according to the present invention.
[0017] Figure label: 1. Mobile phone charging head; 2. Insulating shell; 3. Live wire; 4. Neutral wire; 5. Upper magnetic core; 6. Lower magnetic core; 7. Miniature ventilation hole; 8. Top plate; 9. Sliding column one; 10. Pull-out handle; 11. Clamping plate one; 12. Side plate one; 13. Base plate; 14. Sliding column two; 15. Limiting block; 16. Clamping plate two; 17. Side plate two; 18. Sliding groove; 19. Gear one; 20. Gear two; 21. Rack; 22. Spring one; 23. Spring two; 24. Elastic rope; 25. Rotating sleeve; 26. Fixed column; 27. Charging cable. Detailed Implementation
[0018] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0019] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.
[0020] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0021] Example: like Figure 1 , Figure 2 , Figure 3 As shown, the present invention provides a leakage protection charger, including a mobile phone charging head 1, on which a leakage protection device is installed. The leakage protection device includes an insulating shell 2, and the insulating shell 2 is provided with a rigid clamping and elastic locking mechanism for fixing the mobile phone charging head 1. The rigid clamping and elastic locking mechanism includes a rigid clamping structure and an elastic locking structure.
[0022] The rigid clamping structure includes a top plate 8 and a bottom plate 13 respectively disposed at the top and bottom of the insulating housing 2. A sliding post 9 is slidably disposed on the top plate 8, and a pull handle 10 is disposed at the top of the sliding post 9. The bottom end of a second sliding post 14 passes through the insulating housing 2 and connects to the top end of a clamping plate 11. Side plates 12 are disposed on both sides of the clamping plate 11. A second sliding post 14 is slidably disposed on the bottom plate 13, and a limit block 15 is disposed at the bottom end of the second sliding post 14. The top end of the second sliding post 14 passes through the bottom plate 13 and connects to the bottom end of a clamping plate 16. Side plates 17 are symmetrically disposed on both sides of the clamping plate 16. A sliding groove 18 is disposed within the side plate 12, and the top end of the side plate 17 is inserted into the sliding groove 18 and slidably connected to the sliding groove 18. Several gear sets are evenly arranged from bottom to top on both sides of side plate 2 17. Each gear set includes a meshing gear 19 and a gear 20, which are rotatably connected to side plate 2 17 via rotating shafts. A rack 21, adapted to gear 19 and gear 20, is provided in the sliding groove 18, meshing with the rack 21. Springs 1 22 and 23 are respectively fitted onto sliding pillar 1 9 and sliding pillar 2 14. Spring 1 22 is located between top plate 8 and clamping plate 1 11, and spring 23 is located between bottom plate 13 and clamping plate 2 16. Spring 1 22 is fitted onto sliding pillar 1 9, with its upper end abutting the bottom surface of top plate 8 and its lower end abutting the top surface of clamping plate 11. Spring 23 is fitted onto sliding pillar 2 14, with its upper end abutting the bottom surface of clamping plate 2 16 and its lower end abutting the top surface of bottom plate 13. When the phone charger 1 is not inserted, the elastic force of springs 22 and 23 keeps clamps 11 and 16 tightly fitted. When the handle 10 is pulled open and the phone charger 1 is inserted, the spring's return force becomes the clamping force that holds the charger in place.
[0023] The elastic locking structure includes elastic ropes 24 symmetrically arranged on both sides of the insulating shell 2. The elastic ropes 24 are made of highly elastic, aging-resistant silicone or rubber ropes, which have good insulation and tensile fatigue resistance. Both ends of the elastic ropes 24 are fixed to the rotating sleeve 25. The rotating sleeve 25 is provided with fixing posts 26, which are inserted into the rotating sleeve 25 and rotatably connected to it. The fixing posts 26 are respectively set on the top plate 8 and the bottom plate 13.
[0024] The insulating housing 2 has an output socket for inserting the two prongs of the mobile phone charger 1 and an input pin for charging when plugged into a socket. The live wire 3 and neutral wire 4 connected to the input pin pass through the leakage current detection unit and then connect to the output socket via the power-off unit. The leakage current detection unit is connected to the control unit, which is connected to an environmental sensing unit for monitoring the air humidity of the working environment of the mobile phone charger 1. The control unit, environmental sensing unit, leakage current detection unit, power-off unit, and output socket are located inside the insulating housing 2. The control unit includes an MCU (e.g., STM32G030F6P6), a low-voltage gallium nitride switching power supply, and a Bluetooth module, which is used to connect to the mobile terminal for data transmission.
[0025] The input pins include a live wire 3 input pin, a neutral wire 4 input pin, and a protective ground pin. The live wire 3 input pin and the neutral wire 4 input pin are connected to one end of the live wire 3 and one end of the neutral wire 4, respectively. The output jacks include a live wire 3 output jack and a neutral wire 4 output jack. The power-off unit includes relay one and relay two. The other end of the live wire 3 and the other end of the neutral wire 4 are connected to the live wire 3 output jack and the neutral wire 4 output jack, respectively, through relay one and relay two. The protective ground pin is connected to the protective ground wire. The power-off unit also includes a relay drive circuit. The MCU controls the on / off state of relay one and relay two through the relay drive circuit (using an existing circuit structure, such as the ULN2003 Darlington array, and its specific connection method uses existing electrical connections).
[0026] The leakage current detection unit includes a dual-core leakage current detection module, which is connected to the control unit via signal conditioning circuit one and signal conditioning circuit two. The dual-core leakage current detection module includes an upper core 5 and a lower core 6 arranged parallel and coaxially. The live wire 3 and neutral wire 4, connected to the input pins, pass through the center of the upper core 5 and the lower core 6. A physical gap exists between the upper core 5 and the lower core 6. The upper core 5 is used to detect AC and pulsating DC leakage current, while the lower core 6 is used to detect smooth DC leakage current.
[0027] The upper magnetic core 5 has a secondary winding, which functions as a high-sensitivity current transformer. One end of the secondary winding is grounded, and the other end is connected to the input of signal conditioning circuit one (composed of cascaded basic analog circuit modules such as sampling resistors, differential amplifiers, low-pass filters, voltage followers, and level offsets, with existing electrical connections used for the specific connection method). The output of signal conditioning circuit one is connected to the MCU. The lower magnetic core 6 has two sets of coils wound: an excitation winding and a detection winding. One end of the excitation winding is connected to the output of a push-pull drive circuit (using existing circuit structures, including base current limiting resistors, filter capacitors, transistors, etc., with existing electrical connections used for the specific connection method). The input of the push-pull drive circuit is connected to the MCU, and the other end of the excitation winding is grounded. One end of the detection winding is connected to the input of the signal conditioning circuit two (which is composed of cascaded basic analog circuit modules such as DC blocking capacitor, sampling resistor, differential amplifier, bandpass filter, synchronous detector, and low-pass filter, and its specific connection method adopts the existing electrical connection), and the output of the signal conditioning circuit two is connected to the MCU; the other end of the detection winding is grounded.
[0028] The environmental sensing unit includes a temperature and humidity sensor, a grounding detection circuit, and a reset button. The temperature and humidity sensor is connected to the MCU and is used to monitor the ambient humidity. The temperature and humidity sensor is located above the output jack inside the insulating housing 2, away from heat-generating components such as relays. A miniature ventilation hole 7, communicating with the outside, is provided on the inner wall of the insulating housing 2, directly opposite the temperature and humidity sensor. The reset button (using an existing structure and its specific connection method adopts existing electrical connections) is connected to the MCU on one end and grounded on the other.
[0029] The input terminals of the low-voltage gallium nitride (GaN) switching power supply are connected to live wire 3 (before the relay) and neutral wire 4 (before the relay). The output terminals of the low-voltage GaN switching power supply are connected to the relay drive circuit, push-pull drive circuit, signal conditioning circuit one, signal conditioning circuit two, MCU, Bluetooth module, and temperature and humidity sensor. The grounding detection circuit (using existing circuit structure, including voltage divider resistors, filter capacitors, TVS protection tubes, and current limiting resistors, etc., with specific connections using existing electrical connections) is connected to neutral wire 4, protective ground wire, and MCU. Low-voltage gallium nitride (GaN) devices are introduced into the switching power supply inside the leakage protection head, reducing on-resistance by more than 50% compared to traditional silicon MOSFETs. GaN devices do not have a body diode, eliminating the reverse recovery loss in the freewheeling process of traditional silicon MOSFETs. Innoscience's INN100EA035A, using a 48V to 12V step-down scheme, achieves a peak efficiency of 98.1%, more than 1% higher than silicon solutions. GaN devices have fast switching speeds and low parasitic capacitance, supporting switching frequencies far exceeding those of silicon devices. Furthermore, it can reduce the size and weight of magnetic components such as transformers and inductors by more than 50%, and integrate more functional modules (dual-core leakage detection module, Bluetooth module, etc.) within the limited insulation space of the leakage protection head. GaN material itself allows for higher junction temperatures (typically 150℃), and combined with its low heat generation characteristics, it enables the switching power supply to operate stably even in a sealed housing, avoiding interference with nearby temperature and humidity sensors.
[0030] The main improvements to the internal components of the leakage protection device of this invention are the coordinated improvements to the dual-core leakage detection module, temperature sensor, and Bluetooth module; the remaining circuits use existing circuit connection methods.
[0031] like Figure 4 As shown, the monitoring method for a leakage current protected charger according to the present invention includes the following steps: Step 1, Preparing for charging: Pull the handle 10. The sliding column 9 causes the top plate 8 and side plate 12 to rise. Side plate 17, inside side plate 12, moves downwards via gears and rack 21, allowing the two prongs of the phone charger 1 to be fully inserted into the output socket of the leakage protection device. Release the handle 10. Under the action of springs 22 and 23, top plate 81 descends and top plate 82 rises (rubber clamping points can be set on clamping plates 11 and 16 to improve the clamping effect), clamping the phone charger 1 (applicable to ordinary phone chargers 1, gallium nitride phone chargers 1, etc.). Insert the input pin of the leakage protection device into the target socket and insert one end of the charging cable 27 into the phone charger 1. Pull the elastic cords 24 on both sides of the leakage protection device. The elastic cords 24 are staggered and fixed to the end of the charging cable 27 connected to the phone charger 1 (applicable to ordinary USB ports and Type-C ports of the charging cable 27). In practice, first pull one elastic cord 24 to pass the end of the charging cable 27 away from the phone charger 1 through the inside of the elastic cord 24. Then loosen the elastic cord 24 and adjust its position so that it tightens around the end of the charging cable 27 connected to the phone charger 1. Repeat the same process on the other elastic cord 24. Finally, both elastic cords 24 will be positioned on either side of the charging cable 27, tightening the end of the charging cable 27 connected to the phone charger 1 to secure it. Finally, connect the other end of the charging cable 27 to the phone for charging.
[0032] Before proceeding to the next step of leakage current detection, the leakage current protection device is powered on and initialized, performing a self-test. The MCU reads the current ambient humidity data collected by the temperature and humidity sensors and compares it with the preset safe humidity threshold (80%RH). If the ambient humidity exceeds the safe threshold, the MCU sends an alarm message "Abnormal humidity, high charging risk" to the mobile terminal via Bluetooth module, and controls the relay drive circuit to disconnect relay one and relay two, thus cutting off power to the output jack and preventing electric shock accidents in humid environments. If the humidity is normal, it enters the leakage current monitoring standby state.
[0033] Step 2, Real-time Leakage Detection: AC and pulsating DC leakage current detection: The upper magnetic core 5 senses the vector sum of the currents of the live wire 3 and the neutral wire 4 in real time. When AC or pulsating DC leakage current occurs, the magnetic flux changes, and the secondary winding of the upper magnetic core 5 generates an induced signal. This induced signal is filtered and amplified by the signal conditioning circuit and then transmitted to the MCU.
[0034] Smooth DC leakage detection: The MCU timing control push-pull drive circuit outputs an excitation signal to the excitation winding of the lower magnetic core 6, causing the lower magnetic core 6 to be in an alternating saturation working state. When there is a smooth DC leakage between the live wire 3 and the neutral wire 4, it will cause magnetic flux imbalance. The detection winding of the lower magnetic core 6 will induce a voltage signal containing leakage current information. This voltage signal is processed by the signal conditioning circuit two and then transmitted to the MCU.
[0035] Step 3, Leakage current determination and graded response: The MCU makes a comprehensive judgment based on the leakage current signal received after processing in step two, combined with the ambient humidity data monitored by the temperature and humidity sensor: Determining minor leakage: If the detected leakage current value is lower than or equal to the preset safety action threshold of 10mA, but the ambient humidity is high (close to but not exceeding the power-off threshold in step two), the MCU determines it to be a high-risk state and sends a "humid environment, minor leakage exists, please pay attention to safety" prompt message to the mobile terminal via Bluetooth module. Determining severe leakage: If the detected leakage current value (whether AC, pulsating DC or smooth DC) exceeds the preset safety action threshold of 10mA, the MCU will immediately determine it as a severe leakage fault.
[0036] Step 5, Fault Protection and Remote Alarm: Upon determining a serious leakage fault, the MCU immediately performs a local power cut-off. The MCU instantly cuts off relay one and relay two through the relay drive circuit, disconnecting the output path between the live wire 3 and the neutral wire 4, forcing the mobile phone charger 1 to stop working, and physically eliminating the risk of electric shock.
[0037] At the same time, the MCU packages the leakage current type (AC / pulsating DC / smooth DC), leakage current amplitude, trigger time, and ambient humidity data at the time of triggering, and sends it to the connected mobile terminal via Bluetooth module to inform the user that "the charger has triggered leakage protection and cut off the power supply," reminding the user to check the charging equipment or line.
[0038] Step Six: Manual Reset and Troubleshooting After the leakage protection trips, the circuit remains open to prevent the risk of automatic reset. The user must manually press the reset button on the insulating housing 2 after ruling out external faults such as the phone charger 1, charging cable 27, or socket. When the reset button is pressed, a reset signal is sent to the MCU. Upon receiving the reset signal, the MCU first re-detects whether a leakage fault still exists in the circuit through the leakage detection unit. If no leakage is detected and the ambient humidity has dropped to a safe range, the MCU controls the relay drive circuit to re-engage relays one and two, restoring power supply. If the fault persists, the power is kept off and an alarm message is sent to the mobile terminal again.
[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. A leakage current protection charger, comprising a mobile phone charging head, characterized in that: The mobile phone charger is equipped with a leakage protection device, which includes an insulating shell. The insulating shell has an output socket for inserting the two prongs of the mobile phone charger and an input pin for plugging into a socket for charging. The live wire and neutral wire connected to the input pin pass through the leakage detection unit and are connected to the output socket through a power-off unit. The leakage detection unit is connected to the control unit, which is connected to an environmental sensing unit for monitoring the air humidity of the mobile phone charger's working environment. The leakage detection unit includes a dual-core leakage detection module, which is connected to the control unit through signal conditioning circuit one and signal conditioning circuit two. The insulating shell is equipped with a rigid clamping and elastic locking mechanism for fixing the mobile phone charger.
2. The leakage protection charger according to claim 1, characterized in that: The control unit, environmental sensing unit, leakage detection unit, power-off unit, and output jack are located inside the insulating housing.
3. The leakage protection charger according to claim 1, characterized in that: The input pins include a live wire input pin, a neutral wire input pin, and a protective ground pin. The live wire input pin and the neutral wire input pin are respectively connected to one end of the live wire and one end of the neutral wire. The output jacks include a live wire output jack and a neutral wire output jack. The power-off unit includes relay one and relay two. The other end of the live wire and the other end of the neutral wire are respectively connected to the live wire output jack and the neutral wire output jack through relay one and relay two. The protective ground pin is connected to the protective ground wire.
4. The leakage protection charger according to claim 3, characterized in that: The control unit includes an MCU, a low-voltage gallium nitride switching power supply, and a Bluetooth module, which is used to connect to a mobile terminal for data transmission. The power-off unit also includes a relay drive circuit, through which the MCU controls the on / off state of relay one and relay two respectively.
5. The leakage protection charger according to claim 4, characterized in that: The dual-core leakage current detection module includes an upper core and a lower core arranged in parallel and coaxially. The live wire and neutral wire connected to the input pin pass through the center of the upper and lower cores. A physical gap is left between the upper and lower cores. The upper core is used to detect AC and pulsating DC leakage current, and the lower core is used to detect smooth DC leakage current. A set of secondary windings is wound on the upper core. One end of the secondary windings is grounded, and the other end of the secondary windings is connected to the input terminal of the first signal conditioning circuit. The output terminal of the first signal conditioning circuit is connected to the MCU. The lower magnetic core is wound with two sets of coils: an excitation winding and a detection winding. One end of the excitation winding is connected to the output of the push-pull drive circuit, and the input of the push-pull drive circuit is connected to the MCU. The other end of the excitation winding is grounded. One end of the detection winding is connected to the input of the second signal conditioning circuit, and the output of the second signal conditioning circuit is connected to the MCU. The other end of the detection winding is grounded.
6. The leakage protection charger according to claim 5, characterized in that: The environmental sensing unit includes a temperature and humidity sensor, a grounding detection circuit, and a reset button. The temperature and humidity sensor is connected to the MCU and is used to monitor the humidity of the environment. The temperature and humidity sensor is located above the output socket inside the insulating housing. A miniature ventilation hole that communicates with the outside is opened on the inner wall of the insulating housing, directly opposite the temperature and humidity sensor.
7. The leakage protection charger according to claim 6, characterized in that: One end of the reset button is connected to the MCU, and the other end is grounded. The input terminal of the low-voltage gallium nitride switching power supply is connected to the live wire and the neutral wire. The output terminal of the low-voltage gallium nitride switching power supply is connected to the relay drive circuit, the push-pull drive circuit, the signal conditioning circuit one, the signal conditioning circuit two, the MCU, the Bluetooth module, and the temperature and humidity sensor. The grounding detection circuit is connected to the neutral wire, protective ground wire, and MCU respectively.
8. The leakage protection charger according to claim 1, characterized in that: The rigid clamping and elastic locking mechanism includes a rigid clamping structure and an elastic locking structure. The rigid clamping structure includes a top plate and a bottom plate respectively disposed at the top and bottom of the insulating shell. A sliding post 1 is slidably disposed on the top plate, and a pull handle is disposed at the top of the sliding post 1. The bottom end of the sliding post 2 passes through the insulating shell and connects to the top of the clamping plate 1. Side plates 1 are disposed on both sides of the clamping plate 1. A sliding post 2 is slidably disposed on the bottom plate, and a limit block is disposed at the bottom of the sliding post 2. The top end of the sliding post 2 passes through the bottom plate and connects to the bottom of the clamping plate 2. Side plates 2 are symmetrically disposed on both sides of the clamping plate 2. Side plate one is provided with a sliding groove. The top of side plate two is inserted into the sliding groove and slidably connected to the sliding groove. Several gear sets are evenly arranged on both sides of side plate two from bottom to top. The gear sets include gear one and gear two that are meshed together. Gear one and gear two are rotatably connected to side plate two through rotating shafts. A rack that is adapted to gear one and gear two is provided in the sliding groove. Gear one and gear two are meshed with the rack respectively. Spring one and spring two are respectively sleeved on sliding column one and sliding column two. Spring one is located between the top plate and clamping plate one, and spring two is located between the bottom plate and clamping plate two.
9. The leakage protection charger according to claim 8, characterized in that: The elastic locking structure includes elastic ropes symmetrically arranged on both sides of the insulating shell. Both ends of the elastic ropes are fixed to the rotating sleeve. A fixing post is provided inside the rotating sleeve. The fixing post is inserted into the rotating sleeve and rotatably connected to the rotating sleeve. The fixing post is respectively set on the top plate and the bottom plate.
10. A monitoring method for a leakage current protected charger according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1, Preparing for charging: Pull the handle to open the circuit. Sliding column one will cause the top plate and side plate one to rise. Side plate two, inside side plate one, will descend as side plate one rises, driven by a gear set and rack. Insert the two prongs of the phone charger into the output socket of the leakage protection device. Release the handle. Under the action of spring one and spring two, top plate one will descend and top plate two will rise to clamp the phone charger. Insert the input pin of the leakage protection device into the target socket. Insert one end of the charging cable into the phone charger. Pull the elastic ropes on both sides of the leakage protection device. The elastic ropes are interlaced and fixed to the end of the charging cable connected to the phone charger. Finally, connect the other end of the charging cable to the phone to charge. Step 2, Real-time Leakage Detection: AC and pulsating DC leakage detection: The upper magnetic core senses the vector sum of the currents of the live wire and the neutral wire in real time. When AC or pulsating DC leakage occurs, the secondary winding of the upper magnetic core generates an induced signal. This induced signal is filtered and amplified by the signal conditioning circuit and then transmitted to the MCU. Smooth DC leakage detection: The MCU timing control push-pull drive circuit outputs an excitation signal to the excitation winding of the lower magnetic core, so that the lower magnetic core is in an alternating saturation working state; when there is a smooth DC leakage between the live wire and the neutral wire, the detection winding of the lower magnetic core induces a voltage signal containing leakage current information, which is processed by the signal conditioning circuit two and then transmitted to the MCU. Step 3, Leakage current determination and graded response: The MCU makes a comprehensive judgment based on the leakage current signal received after processing in step two, combined with the ambient humidity data monitored by the temperature and humidity sensor: Determining minor leakage: If the detected leakage current value is lower than or equal to the preset safety action threshold of 10mA and the ambient humidity is high, the MCU determines it to be a high-risk state and sends a "humid environment, minor leakage exists, please pay attention to safety" prompt message to the mobile terminal via Bluetooth module; Determining severe leakage: If the detected leakage current value exceeds the preset safety action threshold of 10mA, the MCU will immediately determine it as a severe leakage fault; Step 5, Fault Protection and Remote Alarm: After a serious leakage fault is determined, the MCU immediately performs a local power cut-off. The MCU instantly cuts off relay one and relay two through the relay drive circuit, disconnecting the output path between the live wire and the neutral wire, and forcing the mobile phone charger to stop working. At the same time, the MCU packages the leakage type, leakage current amplitude, trigger time, and ambient humidity data at the time of triggering, and sends them to the connected mobile terminal via Bluetooth module to inform the user that "the charger has triggered leakage protection and cut off the power", reminding the user to check the charging equipment or line. Step Six: Manual Reset and Troubleshooting After the leakage protection trips, the circuit remains disconnected. After ruling out faults in the phone charger, charging cable, or socket, the user can manually press the reset button on the insulating housing to send a reset signal to the MCU. Upon receiving the reset signal, the MCU first uses the leakage detection unit to re-detect whether there is a leakage fault in the circuit. If no leakage is detected and the ambient humidity has dropped to a safe range, the MCU controls the relay drive circuit to re-engage relay one and relay two, restoring power supply. If the fault exists, the power is kept off and an alarm message is sent to the mobile terminal again.