Protection circuit and charging connection device, charging system

Abstract

The utility model discloses a protection circuit and charging connection device, charging system, this circuit is used for charging connection device, and charging connection device includes the first connecting piece and the second connecting piece of mutual connection, and the first connecting piece is suitable for connecting power supply device, and the second connecting piece is suitable for connecting the power receiving device, and the circuit includes: temperature detection module, temperature detection module sets up in the first connecting piece, DCDC module, DCDC module is connected with temperature detection module, is configured as according to temperature detection module detection temperature and determines whether to stop power supply, switch module, switch module is suitable for connecting power supply device and power receiving device respectively, control module, control module is connected with DCDC module, switch module respectively, and control module is configured as when DCDC module stops power supply, and control switch module disconnects the connection between power supply device and power receiving device. The circuit utilizes DCDC module hardware self -help over -temperature protection function, realizes over -temperature protection, need not software calculation, has over -temperature protection security high advantage.

Description

Technical Field

[0001] This utility model relates to the field of charging technology, and in particular to a protection circuit, a charging connection device, and a charging system. Background Technology

[0002] To prevent overheating during charging, electric vehicles typically install a temperature sensor inside the charger plug. A microcontroller unit (MCU) monitors the temperature collected by the sensor and uses software logic to control the switching on and off of MOSFETs or the opening and closing of relays in the charger's main circuit based on the temperature, thereby terminating charging or discharging.

[0003] Because MCUs may crash and programs may run out of control, relying on software logic to determine the on / off state of the main circuit carries certain risks. Utility Model Content

[0004] This utility model aims to at least partially solve one of the technical problems in related technologies. Therefore, one objective of this utility model is to propose a protection circuit that utilizes the built-in over-temperature protection function of the DC-DC module hardware to achieve over-temperature protection without requiring software calculations, thus offering the advantage of high over-temperature protection safety.

[0005] The second objective of this invention is to provide a charging connection device.

[0006] The third objective of this invention is to provide a charging system.

[0007] To achieve the above objectives, a first aspect of this utility model provides a protection circuit for a charging connection device. The charging connection device includes a first connector and a second connector connected to each other. The first connector is adapted to connect a power supply device, and the second connector is adapted to connect a power receiving device. The circuit includes: a temperature detection module disposed in the first connector; a DC-DC converter module connected to the temperature detection module and configured to determine whether to stop power supply based on the temperature detected by the temperature detection module; a switch module adapted to connect the power supply device and the power receiving device respectively; and a control module connected to the DC-DC converter module and the switch module respectively, configured to control the switch module to disconnect the connection between the power supply device and the power receiving device when the DC-DC converter module stops supplying power.

[0008] According to the protection circuit of this utility model embodiment, the DCDC module has a built-in over-temperature protection function. When the temperature of the first connector detected by the temperature detection module is too high, the DCDC module stops supplying power. This allows the control module to control the switch module to disconnect the connection between the power supply device and the power receiving device when the DCDC module stops supplying power, thus achieving over-temperature protection. No software calculation is required, and it has the advantage of high over-temperature protection safety.

[0009] In addition, the protection circuit proposed according to the above embodiments of this utility model may also have the following additional technical features:

[0010] According to one embodiment of the present invention, the circuit further includes: an AC / CDC module, the DC terminal of the AC / CDC module being connected to the DC / CDC module, the AC terminal of the AC / CDC module being adapted to be connected to the power supply device, and the AC / CDC module being configured to convert the AC power provided by the power supply device into DC power of a first preset voltage; wherein, the DC / CDC module is configured to convert the DC power of the first preset voltage into DC power of a second preset voltage and supply it to the control module.

[0011] According to one embodiment of the present invention, the DC-DC module includes: a DC-DC chip, the enable pin of the DC-DC chip being connected to the temperature detection module, the input pin of the DC-DC chip being connected to the DC terminal of the AC-DC module, and the output pin of the DC-DC chip being connected to the power supply terminal of the control module; and a voltage divider resistor, the first end of which is connected to the input pin of the DC-DC module, and the second end of which is connected to the enable pin of the DC-DC chip.

[0012] According to one embodiment of the present invention, the temperature detection module includes: a temperature control switch, the first end of which is connected to the enable pin of the DC-DC chip, and the second end of which is grounded; and / or a thermistor, the first end of which is connected to the enable pin of the DC-DC chip, and the second end of which is grounded.

[0013] According to one embodiment of the present invention, the switch module includes: a relay having a first contact, a second contact, a third contact, a fourth contact, and a control coil; the first contact is adapted to connect to a first power output terminal of the power supply device; the second contact is adapted to connect to a second power output terminal of the power supply device; the third contact is adapted to connect to a first power input terminal of the power receiving device; the fourth contact is adapted to connect to a second power input terminal of the power receiving device; a first end of the control coil is connected to a control terminal of the control module; and a second end of the control coil is connected to a DC terminal of the ACDC module; wherein, one of the first contact and the third contact is a stationary contact, and the other is a moving contact; the first of the second contact and the fourth contact is a stationary contact, and the other is a moving contact.

[0014] According to one embodiment of the present invention, the control module includes a control chip and a transistor. The power supply pin of the control chip is connected to the power supply terminal of the control module, the ground pin of the control chip is grounded, the input / output pin of the control chip is connected to the base of the transistor, the emitter of the transistor is grounded, and the collector of the transistor is connected to the control terminal of the control module.

[0015] According to one embodiment of the present invention, the control module further includes: a diode, the anode of which is connected to the collector of the transistor, and the cathode of which is connected to the second end of the control coil; a first resistor, the first end of which is connected to the input / output pin of the control chip, and the second end of which is connected to the base of the transistor; and a second resistor, the first end of which is connected to the base of the transistor, and the second end of which is grounded.

[0016] According to one embodiment of the present invention, the ACDC module includes: a rectifier unit, the AC terminal of which is connected to the output terminal of the power supply device; a transformer, the first end of the primary coil of which is connected to the positive terminal of the DC terminal of the rectifier unit, the first end of the primary coil of which is connected to the input pin of the DCDC chip and the second end of the control coil; a switching transistor, the first end of which is connected to the second end of the primary coil of the transformer, and the second end of which is grounded; and an ACDC chip, the drive output pin of which is connected to the control terminal of the switching transistor, the power supply pin of which is connected to the first end of the secondary coil of the transformer, and the second end of the secondary coil of the transformer is grounded.

[0017] To achieve the above objectives, a second aspect of this utility model provides a charging connection device, the device comprising: a first connector adapted to connect to a power supply device; a second connector connected to the first connector via a cable, the second connector being adapted to connect to a power receiving device; and a protection circuit as provided in the first aspect of this utility model.

[0018] The charging connection device according to the present invention utilizes a protection circuit to protect the charging connection device, and has the advantages of low cost and high safety of over-temperature protection.

[0019] In addition, the charging connection device proposed according to the above embodiments of this utility model may also have the following additional technical features:

[0020] According to one embodiment of the present invention, the first connector is adapted to be pluggably connected to a power supply device.

[0021] According to one embodiment of the present invention, the device includes a control box, wherein the control box is connected to the first connector and the second connector respectively via cables, and the DC-DC module, the switch module and the control module in the protection circuit are disposed in the control box.

[0022] According to one embodiment of the present invention, the DC-DC module, the switch module, and the control module in the protection circuit are disposed in the first connector.

[0023] According to one embodiment of the present invention, the first connector is adapted to be fixedly connected to the power supply device.

[0024] According to one embodiment of the present invention, the DC-DC module, the switch module, and the control module in the protection circuit are disposed in the first connector.

[0025] To achieve the above objectives, a third aspect of the present invention provides a charging system, comprising: a power supply device, a power receiving device, and a charging connection device as provided in the second aspect of the present invention.

[0026] The charging system according to the present invention utilizes a charging connection device to realize the charging connection between the power supply device and the power receiving device, which has the advantages of low cost and high safety of over-temperature protection.

[0027] In addition, the charging system proposed according to the above embodiments of this utility model may also have the following additional technical features:

[0028] According to one embodiment of the present invention, the power supply device includes a charging pile, and the power receiving device includes a vehicle.

[0029] Additional aspects and advantages of this invention 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 the invention. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a protection circuit according to an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the protection circuit of another embodiment of the present invention;

[0032] Figure 3 This is a circuit schematic diagram of a DC-DC module according to an embodiment of this utility model;

[0033] Figure 4 This is a circuit diagram of a switch module and a control module according to an embodiment of the present invention;

[0034] Figure 5 This is a circuit schematic diagram of an ACDC module according to an embodiment of this utility model;

[0035] Figure 6 This is a circuit diagram of a protection circuit according to a specific embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of a charging connection device according to an embodiment of the present invention;

[0037] Figure 8 This is a vehicle charging flowchart of a specific embodiment of this utility model;

[0038] Figure 9 This is a schematic diagram of a charging connection device according to an embodiment of the present invention;

[0039] Figure 10 This is a schematic diagram of a charging connection device according to a specific embodiment of the present invention. Figure 1 ;

[0040] Figure 11 This is a schematic diagram of a charging connection device according to a specific embodiment of the present invention. Figure 2 ;

[0041] Figure 12 This is a schematic diagram of a charging connection device according to a specific embodiment of the present invention. Figure 3 ;

[0042] Figure 13 This is a schematic diagram of a charging system according to an embodiment of the present invention. Detailed Implementation

[0043] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0044] The protection circuit, charging connection device, and charging system of this utility model embodiment will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0045] The protection circuit of this utility model embodiment is used for a charging connection device. The charging connection device may include a first connector and a second connector that are connected to each other. The first connector is adapted to connect to a power supply device, and the second connector is adapted to connect to a power receiving device.

[0046] Figure 1 This is a schematic diagram of a protection circuit according to an embodiment of the present invention. Figure 1 As shown, the protection circuit may include:

[0047] A temperature detection module is located in the first connector.

[0048] The DC-DC module is connected to the temperature detection module and is configured to determine whether to stop power supply based on the temperature detected by the temperature detection module.

[0049] A switch module, suitable for connecting a power supply device and a power receiving device respectively;

[0050] The control module is connected to both the DC-DC module and the switch module. The control module is configured to control the switch module to disconnect the power supply device from the power receiving device when the DC-DC module stops supplying power.

[0051] The DC-DC module in this invention has a built-in over-temperature protection function.

[0052] This invention utilizes the built-in over-temperature protection function of the DC-DC module. Based on whether the temperature detected by the temperature detection module exceeds (or is greater than or equal to) a preset temperature threshold, it determines whether to stop the power supply to the DC-DC module. Thus, when the DC-DC module stops supplying power, the control module controls the switch module to disconnect the connection between the power supply device and the power receiving device, thereby achieving over-temperature protection.

[0053] Specifically, a temperature detection module is installed in the first connector to detect the real-time temperature of the first connector. The DC-DC module is connected to the temperature detection module, and determines whether to stop power supply based on whether the temperature detected by the temperature detection module is greater than or equal to a preset temperature threshold.

[0054] The DC-DC module is connected to the temperature detection module. When the temperature detected by the temperature detection module is lower than a preset temperature threshold, the DC-DC module starts working and begins supplying power. When the temperature detected by the temperature detection module is greater than or equal to the preset temperature threshold, the DC-DC module stops working and stops supplying power.

[0055] When the DC-DC module supplies power, the control switch module is activated. When the DC-DC module stops supplying power, the control switch module disconnects the power supply from the receiving device. It should be noted that in this embodiment, the DC-DC module provides the voltage required for the control module to operate.

[0056] The protection circuit in this embodiment utilizes the built-in over-temperature protection function of the DC-DC module. When the temperature of the first connector detected by the temperature detection module is too high, the DC-DC module stops supplying power. This allows the control module to control the switch module to disconnect the connection between the power supply device and the power receiving device when the DC-DC module stops supplying power, thus achieving over-temperature protection. No software calculation is required, and it has the advantage of high over-temperature protection safety.

[0057] In one embodiment of this utility model, such as Figure 2 As shown, the protection circuit may also include:

[0058] The AC / DC module has its DC terminal connected to the DC / DC module and its AC terminal adapted to connect to a power supply device. The AC / DC module is configured to convert the AC power supplied by the power supply device into DC power at a first preset voltage.

[0059] The DC-DC module is configured to convert DC power at a first preset voltage into DC power at a second preset voltage and supply it to the control module.

[0060] Specifically, the AC terminal of the ACDC module is connected to the power supply device via a first connector, and the DC terminal of the ACDC module is connected to the input terminal of the DCDC module. The DCDC module converts the AC power provided by the power supply device into DC power of a first preset voltage, providing the DCDC module with DC power of the first preset voltage. Based on the DC power of the first preset voltage input at the input terminal, the DCDC module converts the DC power of the first preset voltage into DC power of a second preset voltage, providing the control module with the required operating voltage.

[0061] In an embodiment of this utility model, the second preset voltage is determined by the operating voltage required by the control module.

[0062] In one specific embodiment, the first preset voltage may be 12V. The second preset voltage may be 5V or 3.3V, etc., to power the control chip (e.g., MCU) in the control module.

[0063] The DC-DC chip U1 in this embodiment of the present invention is a chip with external overheat protection function.

[0064] In one specific embodiment of this utility model, such as Figure 3 As shown, a DC-DC module may include:

[0065] The enable pin of the DC-DC chip U1 is connected to the temperature detection module, the input pin of the DC-DC chip U1 is connected to the DC terminal of the ACDC module, and the output pin of the DC-DC chip U1 is connected to the power supply terminal of the control module.

[0066] Voltage divider resistor R10 has its first end connected to the input pin of the DC-DC module and its second end connected to the enable pin of the DC-DC chip.

[0067] Specifically, the input (IN) pin of the DC-DC chip U1 is connected to the DC terminal of the ACDC module, and receives the first preset voltage DC power provided by the DC terminal of the ACDC module.

[0068] The enable pin (EN) of the DC-DC chip U1 is connected to the temperature detection module. The input pin (IN) of the DC-DC chip U1 is connected to the first end of the voltage divider resistor R10, and the enable pin (EN) of the DC-DC chip U1 is connected to the second end of the voltage divider resistor R10. The temperature detection module and the voltage divider resistor R10 divide the DC current supplied by the DC terminal of the ACDC module into a first preset voltage. The enable pin (EN) of the DC-DC chip U1 is connected to the voltage generated by the temperature detection module.

[0069] When the temperature of the first connector increases and the voltage generated by the temperature detection module decreases, it indicates that the voltage connected to the enable (EN) pin of the DC-DC chip U1 also decreases. When the temperature of the first connector decreases and the voltage generated by the temperature detection module increases, it indicates that the voltage connected to the enable (EN) pin of the DC-DC chip U1 also increases.

[0070] When the voltage input to the enable (EN) pin of the DC-DC chip U1 is greater than or equal to the reference voltage of the DC-DC module, the DC-DC module operates, and the output (SW) pin of the DC-DC chip U1 begins to supply power to provide the control module with its required operating voltage. When the voltage input to the enable (EN) pin of the DC-DC chip U1 is less than the reference voltage of the DC-DC module, the DC-DC module stops operating, and the output (SW) pin of the DC-DC chip U1 stops supplying power, resulting in no voltage output. It should be noted that the DC-DC chip U1 typically has an internal reference voltage for its enable (EN) pin. The DC-DC chip U1 operates when the voltage input to its enable (EN) pin is greater than or equal to the reference voltage, and stops operating when the voltage is less than the reference voltage.

[0071] It should be noted that the reference voltage of the enable (EN) pin of the DC-DC chip U1 is not set by the user; the value of the reference voltage can be determined by consulting the chip datasheet.

[0072] This embodiment of the utility model abandons the conventional approach of handing the temperature detection value to the MCU software program for judgment and then using software to drive the hardware to achieve protection. Instead, it utilizes the overheat protection function built into the DCDC chip U1 to achieve over-temperature protection without the need for software calculation.

[0073] In this specific embodiment, the output (SW) pin of the DCDC chip U1 is connected to the DC output terminal of the DCDC module, and the DC output terminal of the DCDC module is connected to the power supply terminal of the control module. Figure 3 As shown, a bootstrap capacitor C3 is connected between the DC output terminal of the DC-DC module and the startup (BS) and output (SW) pins of the DC-DC chip U1. The output (SW) pin of the DC-DC chip U1 is connected to the first terminal of the first inductor L1, and the second terminal of the first inductor L1 is connected to the DC output terminal of the DC-DC module. The GND (ground) pin of the DC-DC chip U1 is grounded. The GND pin of the DC-DC chip U1 is connected to the anode of the diode D5, and the cathode of the diode D5 is connected to the SW pin of the DC-DC chip U1. The FB pin of the DC-DC chip U1 is connected to the first terminal of the resistor R11, the second terminal of the resistor R11 is connected to the power supply terminal of the DC-DC module, the first terminal of the resistor R11 is connected to the first terminal of the resistor R12, the second terminal of the resistor R12 is grounded, the second terminal of the resistor R12 is connected to the first terminal of the capacitor C4, and the second terminal of the capacitor C4 is connected to the power supply terminal of the DC-DC module. The feedback (FB) pin of the DC-DC chip U1 is used for the DC-DC chip U1 to adjust the accuracy of the DC-DC module output voltage VCC.

[0074] In this embodiment, the enable (EN) pin of the DC-DC chip U1 is also the temperature detection pin of the DC-DC chip U1. The input (IN) pin of the DC-DC chip U1 is also the power supply pin of the DC-DC chip U1. The output (SW) pin of the DC-DC chip U1 is also the switching pin of the DC-DC chip U1.

[0075] It should be noted that, in this embodiment of the present invention, the resistance value of the voltage divider resistor R10 can be determined based on the magnitude of the first preset voltage, the reference voltage of the DCDC chip U1, the preset temperature threshold, and the temperature detection module.

[0076] In one specific embodiment of this utility model, the temperature detection module may include: a temperature control switch, the first end of which is connected to the enable pin of the DC-DC chip U1, and the second end of which is grounded; and / or a thermistor, the first end of which is connected to the enable pin of the DC-DC chip U1, and the second end of which is grounded.

[0077] In embodiments of this invention, the temperature detection module may employ a temperature control switch, a thermistor, or the like. The thermistor may be a negative temperature coefficient (NTC) thermistor.

[0078] For example, when the temperature detection module is a negative temperature coefficient temperature sensor, when the temperature of the first connector rises, the resistance of the temperature sensor decreases, and the voltage value generated by the temperature sensor also decreases; when the temperature of the first connector falls, the resistance of the temperature sensor increases, and the voltage value generated by the temperature sensor also increases.

[0079] The enable pin of the DC-DC module is connected to the temperature detection module. The voltage value generated by the temperature detection module controls whether the DC-DC module stops supplying power. Specifically, when the voltage value is greater than or equal to the DC-DC module's reference voltage, the DC-DC module operates and starts supplying power. When the voltage value is less than the DC-DC module's reference voltage, the DC-DC module stops operating and stops supplying power.

[0080] In one embodiment of this utility model, such as Figure 4 As shown, the switch module may include:

[0081] Relay K3 has a first contact, a second contact, a third contact, a fourth contact, and a control coil. The first contact is adapted to connect to the first power output terminal of the power supply device, the second contact is adapted to connect to the second power output terminal of the power supply device, the third contact is adapted to connect to the first power input terminal of the power receiving device, and the fourth contact is adapted to connect to the second power input terminal of the power receiving device. The first end of the control coil is connected to the control terminal of the control module, and the second end of the control coil is connected to the DC terminal of the ACDC module.

[0082] Among them, one of the first contact and the third contact is a stationary contact, and the other is a moving contact; among the second contact and the fourth contact, the first is a stationary contact, and the other is a moving contact.

[0083] Specifically, the first and second contacts of relay K3 are connected to the first and second power output terminals of the power supply device, respectively, and the third and fourth contacts of relay K3 are connected to the first and second power input terminals of the power receiving device, respectively. The control terminal of the control module is connected to the first terminal of the control coil, and the DC terminal of the AC / DC module is connected to the second terminal of the control coil. The control terminal of the control module can control the active contact of relay K3 to open or close, thus controlling relay K3 to open or close.

[0084] In one specific embodiment of this utility model, such as Figure 4 As shown, the control module may include:

[0085] The control chip U3 and transistor Q1 are connected. The power supply (VCC) pin of the control chip U3 is connected to the power supply terminal of the control module. The ground (GND) pin of the control chip U3 is grounded. The input / output (IO) pin of the control chip U3 is connected to the base (B) of the transistor Q1. The emitter (E) of the transistor Q1 is grounded. The collector (C) of the transistor is connected to the control terminal of the control module.

[0086] In practice, the control chip U3 uses an MCU.

[0087] In this embodiment, transistor Q1 is an NPN transistor. The base (B) of NPN transistor Q1 is connected to the input / output (IO) pin of control chip U3, the emitter (E) of transistor Q1 is grounded, and the collector (C) of transistor Q1 is connected to the control terminal of control module.

[0088] Specifically, when the DC-DC module stops supplying power, there is no power input to the control module's power supply terminal, the control chip U3 does not operate, and transistor Q1 is turned off, thereby controlling relay K3 to open and disconnect the connection between the power supply device and the powered device. When the DC-DC module is supplying power, the required voltage is provided to the control module's power supply terminal, the control chip U3 operates, and transistor Q1 conducts, thereby controlling relay K3 to close and connect the power supply device and the powered device.

[0089] In one embodiment of this utility model, such as Figure 4 As shown, the control module may also include:

[0090] Diode D2, the anode of diode D2 is connected to the collector of transistor Q1, and the cathode of diode D2 is connected to the second terminal of the control coil;

[0091] The first resistor R1 has its first end connected to the IO pin of the control chip, and its second end connected to the base of the transistor Q1.

[0092] The second resistor R2 has its first end connected to the base of transistor Q1, and its second end grounded.

[0093] Specifically, diode D2 is connected between the collector of transistor Q1 and the second terminal of the control coil. A first resistor R1 is connected between transistor Q1 and the I / O pin of the control chip to provide a bias voltage for transistor Q1, enabling it to operate normally. The base of transistor Q1 is grounded through a second resistor R2 to cancel noise and electromagnetic interference, prevent circuit drift, and improve circuit stability.

[0094] In one specific embodiment, such as Figure 5 As shown, the ACDC module includes:

[0095] The rectifier unit has its AC terminal connected to the output terminal of the power supply device.

[0096] The transformer has its primary coil connected to the positive terminal of the DC rectifier unit. The primary coil of transformer T1A is connected to the input pin of DC-DC chip U1 and the second terminal of the control coil, respectively.

[0097] Switch Q2 is connected to the second terminal of the primary coil of transformer T1A, and the second terminal of switch Q2 is grounded.

[0098] The ACCDC chip's drive output (DRV) pin is connected to the control terminal of the switching transistor Q2, and the ACCDC chip's power supply pin is connected to the first terminal of the transformer's secondary winding. The second terminal of the transformer T1A's secondary winding is grounded.

[0099] Specifically, the rectifier unit, transformer, switch Q2, and ACDC chip work together to convert the AC power supplied by the power supply device into DC power with a first preset voltage.

[0100] In this embodiment, such as Figure 5 As shown, the positive terminal of the DC terminal of the rectifier unit is connected to the anode of the electrolytic capacitor CE1, and the cathode of the electrolytic capacitor CE1 is grounded.

[0101] In this embodiment, such as Figure 5 As shown, the first end of the primary coil is connected to the positive DC terminal of the AC / DC module, the first end of the primary coil is connected to the anode of diode D4, the cathode of diode D4 is connected to the positive DC terminal of the AC / DC module, and an electrolytic capacitor CE2 is connected between the second end of the primary coil and the cathode of diode D4.

[0102] In this embodiment, such as Figure 5 As shown, the first terminal of the transformer's secondary winding is connected to the anode of diode D6, the cathode of diode D6 is connected to the first terminal of capacitor R13, and the second terminal of capacitor R13 is connected to the power supply (ADD) pin of the ACDC chip. The first terminal of the transformer's secondary winding is connected to the first terminal of resistor R15, the second terminal of resistor R15 is connected to the first terminal of resistor R18, and the second terminal of resistor R18 is grounded. The cathode of diode D6 is connected to the anode of electrolytic capacitor CE3, and the cathode of electrolytic capacitor CE3 is grounded. The compensation (COMP) pin of the ACDC chip is grounded through resistor R17. The ground (GND) pin of the ACDC chip is grounded, and the drive output (DRV) pin of the ACDC chip is connected to the control terminal of switching transistor Q2 through resistor R14. The second terminal of switching transistor Q2 is grounded through resistor R16.

[0103] It should be noted that the present invention does not limit the structure and circuit of the DC-DC module and the A-DC module.

[0104] The protection circuit in this embodiment can be used in the charging connection device of electronic devices such as mobile phones and automobiles.

[0105] As a specific embodiment, in a vehicle-use charging connection device, the first connector can be a three-prong plug, and the second connector can be a charging gun head. The charging connection device may also include a CP communication module, a grounding detection module, a voltage detection module, a leakage current detection module, a current detection module, a relay sticking detection module, and a short circuit detection module, etc. (See [reference]). Figure 7 .

[0106] The principle of the protection circuit in this embodiment of the invention will be explained using a charging connection device for a vehicle:

[0107] After connecting the first connector to the mains power, the ACDC module converts the mains power to 12VDC, powering the CP communication module, relay K3 driver, and other modules. Simultaneously, the DC-DC module converts the 12VDC to VCC, which powers the MCU, initiating MCU operation. At this time, the temperature sensor data is transmitted to the DC-DC module in real-time. After connecting the second connector to the vehicle, the relay is in the open state. The MCU control module performs a self-test to determine if charging the vehicle is possible. It communicates with the vehicle via the CP signal line to verify that the charging connection meets the vehicle's charging requirements. Upon completion of the self-test and ensuring the CP signal voltage is within the allowable charging range, the MCU outputs a high-level signal, transistor Q1 conducts, the main circuit relay K3 closes, and charging begins. The temperature sensor continuously monitors the temperature of the first connector and transmits the temperature value to the DC-DC module via cable.

[0108] When the temperature of the first connector is abnormal, and the temperature sensor reading exceeds the set value (preset temperature threshold), the DC-DC module will internally adjust to disconnect the VCC output, stop powering the MCU control module, and simultaneously disconnect transistor Q1 and relay K3. When the temperature sensor detects that the temperature has returned to below the set value, the DC-DC module will restore power, and the MCU will record the fault information. See the control flow above. Figure 8 The flowchart shown.

[0109] This embodiment of the utility model utilizes the overheat protection function built into the DCDC chip U1 to achieve over-temperature protection. The control process does not involve direct control of the main circuit relay drive, nor does it rely on the MCU software logic for temperature judgment. Therefore, it greatly reduces the risk of temperature runaway caused by poor contact of the first connector, while simplifying the MCU program and reducing the possibility of MCU runaway.

[0110] This utility model provides a charging connection device.

[0111] Figure 9 This is a schematic diagram of a charging connection device according to an embodiment of the present invention. Figure 9 As shown, the charging connection device may include:

[0112] First connector 10, adapted to connect to power supply device;

[0113] The second connector 20 is connected to the first connector via a cable, and the second connector is adapted to connect to a power receiving device.

[0114] The protection circuit described above.

[0115] Specifically, the protection circuit may include a temperature detection module, a DC-DC converter module, a switch module, a control module, and an ADC converter module. The temperature acquisition module in the protection circuit is integrated into the first connector to collect the real-time temperature of the first connector when the charging device is charging, and the protection circuit provides over-temperature protection for the charging device. The control module may use an MCU as the control chip.

[0116] In this embodiment of the utility model, the charging connection device 100 may further include a CP communication module, a grounding detection module, a voltage detection module, a leakage current detection module, a current detection module, a relay sticking detection module, and a short circuit detection module, etc.

[0117] The cable in this embodiment may include a neutral wire, a live wire, a ground wire, a temperature sensor signal line, etc., and the change value of the temperature sensor is transmitted to the DC-DC module through the cable.

[0118] In this embodiment of the invention, when the first connector 10 is connected to the mains power, the DC-DC module converts the mains power to 12V DC power, and then steps down the 12V to VCC (5V or 3.3V) to power the MCU. The temperature sensor signal line is connected to the DC-DC chip U1 and monitors the temperature inside the first connector 10 in real time. When the temperature sensor value exceeds the preset temperature threshold, the DC-DC chip U1 disconnects its output through its over-temperature protection function, stops supplying power to the MCU, thereby disconnecting the MCU's control over the relay drive circuit, i.e., turning off the transistor Q1, disconnecting the relay, and stopping vehicle charging.

[0119] The charging circuit of the charging connection device 100 is controlled by detecting the temperature of the first connector 10 using the DC-DC chip U1. There is no main circuit relay circuit. The existing DC-DC module circuit is used to achieve this, without adding additional circuits and components, which reduces the cost and simplifies the MCU program. Temperature judgment is not required through the MCU software logic, which reduces the risk of MCU malfunction.

[0120] In an embodiment of this utility model, the first connector is adapted to be pluggably connected to a power supply device.

[0121] As a specific example, such as Figure 10 As shown, the charging connection device 100 includes a control box 30, wherein the control box 30 is connected to the first connector 10 and the second connector 20 respectively via cables, and the DC-DC module, the switch module and the control module in the protection circuit are disposed in the control box 30.

[0122] Implementably, the first connector 10 is an input three-prong plug, and the second connector 20 is an output nozzle. The temperature acquisition module is integrated into the input three-prong plug. The DC-DC module, switch module, and control module in the protection circuit, as well as the CP communication module, grounding detection module, voltage detection module, leakage current detection module, current detection module, relay sticking detection module, and short circuit detection module in the charging connection device 100, are all housed in the control box 30.

[0123] As another specific embodiment, such as Figure 11 As shown, the DC-DC module, switch module, and control module in the protection circuit are located in the first connector 10.

[0124] Implementably, the first connector 10 is an integrated three-prong plug, and the second connector 20 is an output nozzle. The temperature acquisition module is integrated near the integrated three-prong plug. The DC-DC module, switch module, and control module in the protection circuit, as well as the CP communication module, grounding detection module, voltage detection module, leakage current detection module, current detection module, relay sticking detection module, and short circuit detection module in the charging connection device 100, are all located in the first connector 10.

[0125] In an embodiment of this utility model, the first connector is adapted to be fixedly connected to the power supply device.

[0126] As a specific example, such as Figure 12 As shown, the DC-DC module, switch module, and control module in the protection circuit are located in the first connector 10.

[0127] In an achievable configuration, the first connector 10 is an input terminal block, and the second connector 20 is an output nozzle. The temperature acquisition module is integrated near the input terminal block. The DC-DC module, switch module, and control module in the protection circuit, as well as the CP communication module, grounding detection module, voltage detection module, leakage current detection module, current detection module, relay sticking detection module, and short circuit detection module in the charging connection device 100, are all located in the first connector 10.

[0128] The charging connection device in this embodiment can also be a portable charging device with a three-prong plug, or it can be used in a fixed charging station, including a DC charging device and an AC charging device.

[0129] In related technologies, low-power DC charging connection devices typically use an MCU to control the switching of MOSFETs in the main circuit to regulate the DC charging current. However, this method requires driving multiple MOSFETs in the main circuit, leading to an increase in the required current and a risk of MCU malfunction.

[0130] In contrast, the charging connection device in this embodiment transmits data to the DC-DC module in the control box via a temperature sensor during operation. Based on the feedback value from the temperature sensor, the DC-DC module directly controls its output, thereby disconnecting the VCC power supply and directly affecting the normal operation of the MCU and other power-consuming modules, thus achieving precise control over the car charging process.

[0131] This utility model provides a charging system.

[0132] Figure 13 This is a schematic diagram of a charging system according to an embodiment of the present invention. Figure 13 As shown, the charging system 1000 includes: a power supply device 200, a power receiving device 300, and a charging connection device 100 as described above.

[0133] In one specific embodiment, the power supply device may include a charging station, and the power receiving device may include a vehicle.

[0134] The charging system of this utility model embodiment has the advantages of low cost and high safety when using the charging connection device 100 to control the charging circuit between the power supply device and the power receiving device.

[0135] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "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 the present invention. 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.

[0136] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0137] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0138] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0139] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0140] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A protection circuit, characterized in that, A charging connection device, the charging connection device including a first connector and a second connector connected to each other, the first connector being adapted to connect to a power supply device, and the second connector being adapted to connect to a power receiving device, the circuit including: A temperature detection module is disposed in the first connector; A DC-DC module includes a DC-DC chip, wherein the enable pin of the DC-DC chip is connected to the temperature detection module and is configured to determine whether to stop power supply based on the temperature detected by the temperature detection module, wherein the DC-DC chip has an over-temperature protection function. A switching module, the switching module being adapted to connect the power supply device and the power receiving device respectively; A control module is connected to the DC-DC module and the switch module respectively. The control module is configured to control the switch module to disconnect the connection between the power supply device and the power receiving device when the DC-DC module stops supplying power.

2. The protection circuit according to claim 1, characterized in that, The circuit also includes: An AC / DC module is provided, wherein the DC terminal of the AC / DC module is connected to the DC / DC module, and the AC terminal of the AC / DC module is adapted to be connected to the power supply device. The AC / DC module is configured to convert the AC power provided by the power supply device into DC power with a first preset voltage. The DC-DC module is configured to convert the DC power of the first preset voltage into the DC power of the second preset voltage and supply it to the control module.

3. The protection circuit according to claim 2, characterized in that, The DC-DC module includes: The DC-DC chip has its input pins connected to the DC terminal of the ACDC module, and its output pins connected to the power supply terminal of the control module. A voltage divider resistor, the first end of which is connected to the input pin of the DC-DC module, and the second end of which is connected to the enable pin of the DC-DC chip.

4. The protection circuit according to claim 3, characterized in that, The temperature detection module includes: A temperature control switch, wherein the first terminal of the temperature control switch is connected to the enable pin of the DC-DC chip, and the second terminal of the temperature control switch is grounded; and / or A thermistor, the first end of which is connected to the enable pin of the DC-DC chip, and the second end of which is grounded.

5. The protection circuit according to claim 2, characterized in that, The switching module includes: A relay having a first contact, a second contact, a third contact, a fourth contact, and a control coil; the first contact is adapted to connect to a first power output terminal of the power supply device; the second contact is adapted to connect to a second power output terminal of the power supply device; the third contact is adapted to connect to a first power input terminal of the power receiving device; the fourth contact is adapted to connect to a second power input terminal of the power receiving device; a first end of the control coil is connected to the control terminal of the control module; and a second end of the control coil is connected to the DC terminal of the ACDC module. Among them, one of the first contact and the third contact is a stationary contact, and the other is a moving contact; the first of the second contact and the fourth contact is a stationary contact, and the other is a moving contact.

6. The protection circuit according to claim 5, characterized in that, The control module includes a control chip and a transistor. The power supply pin of the control chip is connected to the power supply terminal of the control module, the ground pin of the control chip is grounded, the input and output pins of the control chip are connected to the base of the transistor, the emitter of the transistor is grounded, and the collector of the transistor is connected to the control terminal of the control module.

7. The protection circuit according to claim 6, characterized in that, The control module also includes: A diode, wherein the anode of the diode is connected to the collector of the transistor, and the cathode of the diode D2 is connected to the second terminal of the control coil; A first resistor, the first end of which is connected to the input / output pin of the control chip, and the second end of which is connected to the base of the transistor; The second resistor has its first end connected to the base of the transistor and its second end grounded.

8. The protection circuit according to claim 5, characterized in that, The ACDC module includes: A rectifier unit, wherein the AC terminal of the rectifier unit is connected to the output terminal of the power supply device; A transformer, wherein the first end of the primary coil of the transformer is connected to the positive terminal of the DC terminal of the rectifier unit, and the first end of the primary coil of the transformer is connected to the input pin of the DC-DC chip and the second end of the control coil, respectively. Switch Q2, the first end of which is connected to the second end of the primary coil of transformer T1A, and the second end of switch Q2 is grounded; An AC / CDC chip is used, wherein the drive output pin of the AC / CDC chip is connected to the control terminal of the switching transistor Q2, the power supply pin of the AC / CDC chip is connected to the first terminal of the second stage coil of the transformer, and the second terminal of the second stage coil of the transformer is grounded.

9. A charging connection device, characterized in that, The device includes: The first connector is adapted to connect a power supply device; The second connector is connected to the first connector via a cable, and the second connector is adapted to connect to a power receiving device. The protection circuit as described in any one of claims 1-8.

10. The charging connection device according to claim 9, characterized in that, The first connector is adapted to be pluggably connected to a power supply device.

11. The charging connection device according to claim 10, characterized in that, The device includes a control box, wherein the control box is connected to the first connector and the second connector respectively via cables, and the DC-DC module, switch module and control module of the protection circuit are disposed in the control box.

12. The charging connection device according to claim 10, characterized in that, The DC-DC module, switch module, and control module in the protection circuit are located in the first connector.

13. The charging connection device according to claim 9, characterized in that, The first connector is adapted to be fixedly connected to the power supply device.

14. The charging connection device according to claim 13, characterized in that, The DC-DC module, switch module, and control module in the protection circuit are located in the first connector.

15. A charging system, characterized in that, include: A power supply device, a power receiving device, and a charging connection device as described in any one of claims 9-14.

16. The charging system according to claim 15, characterized in that, The power supply device includes a charging pile, and the power receiving device includes a vehicle.

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