A charging protection circuit system

Abstract

This utility model proposes a charging protection circuit system, including a power supply input module, a relay drive module, a power conversion module, a current detection module, a control module, and a status indication module. The current detection module includes a current transformer, a signal conditioning circuit, and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through a filter capacitor C2. This system uses precise current detection and intelligent judgment to enable the relay to act as a power-off actuator, achieving multi-functional control with precise control, fast response, and significant energy savings. At the same time, the use of a filter improves anti-interference capability and ensures accurate judgment. Combined with the efficient relay drive, it further achieves fast and reliable execution.

Description

Technical Field

[0001] This utility model relates to the field of charging safety protection technology, and more specifically, to a charging protection circuit system. Background Technology

[0002] The closest existing technology, authorized by CN218783719U, discloses a current-type control circuit, which includes a current transformer module, a window comparator module, a signal isolation module, and an integrated monostable circuit module. The current transformer module includes a measuring current transformer TA1, a precision current transformer TA2, and a sampling resistor R1; the window comparator module includes operational amplifiers U1A and U1B, diodes D1 and D2, and a pull-down resistor R2; the signal isolation module includes an optocoupler U2, a resistor R3, a capacitor R4, a capacitor R5, a capacitor R6, a capacitor R7, and a capacitor C1; the integrated monostable circuit module includes a monostable trigger circuit U3 and a relay K1.

[0003] This power control technology can achieve current blocking, but it has fundamental limitations: its window comparator only outputs pulse signals and cannot quantify the current value; and it is a monostable circuit, which is susceptible to noise interference (such as false triggering caused by power grid harmonics).

[0004] In addition, mechanical timer sockets on the market will forcibly cut off the power at the set time, which may interrupt the normal charging process; while smart network solutions are too expensive to be widely adopted in homes.

[0005] Therefore, there is an urgent need for a charging protection circuit system in the existing charging protection system that can quantify current detection and effectively resist interference. Utility Model Content

[0006] The purpose of this invention is to propose a charging protection circuit system that can quantify current detection and effectively resist interference.

[0007] A charging protection circuit system, characterized in that it comprises:

[0008] The power input module includes AC-L and AC-N terminals for connecting to an AC power source.

[0009] A relay drive module includes a relay JK1 and a switching circuit that controls the on / off state of its coil. The switching circuit includes a MOS transistor Q1 and a control signal terminal connected to its gate.

[0010] The power conversion module is used to convert the input AC power into 3.3V DC voltage;

[0011] The current detection module is used to detect the current flowing through the power supply input terminal and generate a corresponding detection signal. The current detection module includes a current transformer, a signal conditioning circuit and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through filter capacitor C2.

[0012] The control module includes an MCU chip, which is configured with: an analog-to-digital converter (ADC) pin connected to the output of the current detection module for receiving the detection signal; a general purpose input / output (GPIO) pin connected to the gate of the MOSFET Q1 for outputting the control signal; and a status indication module connected to the GPIO pin of the MCU chip for receiving the control signal and indicating the status.

[0013] Furthermore, the reference voltage source is provided by a resistor divider network, which includes resistors R3 and R4, and the reference voltage is 1.65V.

[0014] In some embodiments, the signal conditioning circuit includes a π-type LC filter, the input of which is connected to the output of the operational amplifier circuit U1A, and the output of which is connected to the ADC pin of the MCU chip. The π-type LC filter includes an inductor L1, a capacitor C3, and a capacitor C4. An inductor L1 is provided between the output of the operational amplifier circuit U1A and the ADC pin of the MCU chip. The input and output of the inductor L1 are respectively connected to capacitors C3 and C4.

[0015] Furthermore, the inductor L1 of the π-type LC filter has a value range of 10-100μH, and the capacitors C3 and C4 have a value range of 0.1-1μF, with a cutoff frequency ≤1kHz.

[0016] In some embodiments, the relay drive module further includes a freewheeling diode D3 connected in parallel across the coil of relay JK1. The anode of the freewheeling diode D3 is connected to the source of the MOS transistor Q1, and the cathode is connected to the power supply terminal of the relay JK1 coil.

[0017] In some implementations, a serial communication module is also included, which includes a level conversion chip U3 and a communication interface J1. The serial data transmission pin and the receiving pin of the level conversion chip U3 are respectively connected to the corresponding pins of the MCU chip.

[0018] In some implementations, the status indicator module uses a tri-color LED. In the common cathode or common anode connection mode of the tri-color LED, each color channel is connected to the corresponding GPIO pin of the MCU chip through an independent current-limiting resistor.

[0019] In some embodiments, the control module further includes an external EEPROM memory U2 connected to the MCU chip via an I²C bus for storing system parameters, including normal current range threshold, standby current threshold, overcurrent protection threshold, and preset time parameters.

[0020] Furthermore, the control module is configured to perform the following determinations: First, it converts the voltage signal output by the current detection module into a real-time current value using an ADC; then, it controls the relay's on / off state according to preset control logic and threshold parameters stored in the EEPROM. The preset control logic includes: normal power supply mode, standby / sleep cutoff mode, and overcurrent protection mode.

[0021] Normal power consumption mode: When the real-time current value is within the normal operating range, the control relay JK1 remains closed to continuously supply power;

[0022] Standby / Sleep Cut-off Mode: When the real-time current value is lower than the set standby threshold and continues for a preset time (e.g., 60 seconds), the control relay JK1 is disconnected to cut off the power supply;

[0023] Overcurrent protection mode: When the real-time current value exceeds the set overcurrent protection threshold, the relay JK1 is immediately disconnected to cut off the power supply.

[0024] The beneficial effects of this utility model are as follows: This utility model proposes a charging protection circuit system, including a power supply input module, a relay drive module, a power conversion module, a current detection module, a control module, and a status indication module. The current detection module includes a current transformer, a signal conditioning circuit, and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through a filter capacitor C2. This system uses precise current detection and intelligent judgment to enable the relay to act as a power-off actuator, achieving multi-functional control with precise control, fast response, and significant energy savings. At the same time, the use of a filter improves anti-interference capability and ensures accurate judgment. Combined with the efficient relay drive, it further achieves fast and reliable execution. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the module connection structure of the charging protection circuit system of this application.

[0026] Figure 2 This is a schematic diagram of the circuit structure of the charging protection circuit system of this application.

[0027] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this utility model. Detailed Implementation

[0028] The following embodiments are described to aid in understanding this application. These embodiments are not, and should not be, construed in any way as limiting the scope of protection of this application.

[0029] In the following description, those skilled in the art will recognize that throughout this discussion, components may be described as individual functional units (which may include subunits), but those skilled in the art will recognize that various components or portions thereof may be divided into individual components or may be integrated together (including integrated within a single system or component).

[0030] Furthermore, the connection between components or systems is not intended to be limited to a direct connection; on the contrary, data between these components may be modified, reformatted, or otherwise altered by intermediate components. Additionally, other or fewer connections may be used. It should also be noted that the terms "connection," "link," or "input" should be understood to include direct connections, indirect connections via one or more intermediate devices, and wireless connections. Example 1:

[0031] like Figure 1 The diagram shown is a schematic of the module connection structure of the charging protection circuit system of this application; as shown... Figure 2 The diagram shown is a schematic diagram of the circuit structure of the charging protection circuit system of this application.

[0032] A charging protection circuit system, characterized in that it comprises:

[0033] The power input module includes AC-L and AC-N terminals for connecting to an AC power source.

[0034] A relay drive module includes a relay JK1 and a switching circuit that controls the on / off state of its coil. The switching circuit includes a MOS transistor Q1 and a control signal terminal connected to its gate.

[0035] The power conversion module is used to convert the input AC power into 3.3V DC voltage;

[0036] The current detection module is used to detect the current flowing through the power supply input terminal and generate a corresponding detection signal. The current detection module includes a current transformer, a signal conditioning circuit and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through filter capacitor C2.

[0037] The control module includes an MCU chip, which is configured with: an analog-to-digital converter (ADC) pin connected to the output of the current detection module for receiving the detection signal; a general purpose input / output (GPIO) pin connected to the gate of the MOSFET Q1 for outputting the control signal; and a status indication module connected to the GPIO pin of the MCU chip for receiving the control signal and indicating the status.

[0038] The reference voltage source is provided by a resistor divider network, which includes resistors R3 and R4, and the reference voltage is 1.65V.

[0039] The signal conditioning circuit includes a π-type LC filter, the input of which is connected to the output of the operational amplifier circuit U1A, and the output of which is connected to the ADC pin of the MCU chip. The π-type LC filter includes an inductor L1, a capacitor C3, and a capacitor C4. An inductor L1 is provided between the output of the operational amplifier circuit U1A and the ADC pin of the MCU chip. The input and output of the inductor L1 are respectively connected to capacitors C3 and C4.

[0040] The inductor L1 of the π-type LC filter has a value range of 10-100μH, and the capacitors C3 and C4 have a value range of 0.1-1μF. The cutoff frequency is ≤1kHz.

[0041] The relay drive module also includes a freewheeling diode D3 connected in parallel across the coil of relay JK1. The anode of the freewheeling diode D3 is connected to the source of the MOS transistor Q1, and the cathode is connected to the power supply terminal of the relay JK1 coil.

[0042] It also includes a serial communication module, which includes a level conversion chip U3 and a communication interface J1. The serial data transmission pin and the receiving pin of the level conversion chip U3 are respectively connected to the corresponding pins of the MCU chip.

[0043] The status indicator module uses tri-color LEDs. In the common cathode or common anode connection mode of the tri-color LEDs, each color channel is connected to the corresponding GPIO pin of the MCU chip through an independent current-limiting resistor.

[0044] The control module also includes an external EEPROM memory U2 connected to the MCU chip via an I²C bus, used to store system parameters, including normal current range threshold, standby current threshold, overcurrent protection threshold, and preset time parameters.

[0045] The control module is configured to perform the following determinations: First, it converts the voltage signal output by the current detection module into a real-time current value using an ADC; then, it controls the relay's on / off state according to preset control logic and threshold parameters stored in the EEPROM. The preset control logic includes: normal power supply mode, standby / sleep cutoff mode, and overcurrent protection mode.

[0046] Normal power consumption mode: When the real-time current value is within the normal operating range, the control relay JK1 remains closed to continuously supply power;

[0047] Standby / Sleep Cut-off Mode: When the real-time current value is lower than the set standby threshold and continues for a preset time (e.g., 60 seconds), the control relay JK1 is disconnected to cut off the power supply;

[0048] Overcurrent protection mode: When the real-time current value exceeds the set overcurrent protection threshold, the relay JK1 is immediately disconnected to cut off the power supply.

[0049] The beneficial effects of this utility model are as follows: This utility model proposes a charging protection circuit system, including a power supply input module, a relay drive module, a power conversion module, a current detection module, a control module, and a status indication module. The current detection module includes a current transformer, a signal conditioning circuit, and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through a filter capacitor C2. This system uses precise current detection and intelligent judgment to enable the relay to act as a power-off actuator, achieving multi-functional control with precise control, fast response, and significant energy savings. At the same time, the use of a filter improves anti-interference capability and ensures accurate judgment. Combined with the efficient relay drive, it further achieves fast and reliable execution.

[0050] Although this application discloses several aspects and embodiments, other aspects and embodiments will be obvious to those skilled in the art. Various modifications and improvements can be made without departing from the concept of this application, and all such modifications and improvements fall within the scope of protection of this application. The various aspects and embodiments disclosed in this application are for illustrative purposes only and are not intended to limit this application. The actual scope of protection of this application is determined by the claims.

Claims

1. A charging protection circuit system, characterized by, include: The power input module includes AC-L and AC-N terminals for connecting to an AC power source. A relay drive module includes a relay JK1 and a switching circuit that controls the on / off state of its coil. The switching circuit includes a MOS transistor Q1 and a control signal terminal connected to its gate. The power conversion module is used to convert the input AC power into 3.3V DC voltage; The current detection module is used to detect the current flowing through the power supply input terminal and generate a corresponding detection signal. The current detection module includes a current transformer, a signal conditioning circuit and an operational amplifier circuit. The operational amplifier circuit includes operational amplifier U1A and operational amplifier U1B. The non-inverting input terminal of operational amplifier U1B is connected to a reference voltage source, and the inverting input terminal of operational amplifier U1B is grounded through filter capacitor C2. The control module includes an MCU chip, which is configured with: an analog-to-digital converter (ADC) pin connected to the output of the current detection module for receiving the detection signal; and a general-purpose input / output (GPIO) pin connected to the gate of the MOSFET Q1 for outputting the control signal. The status indication module is connected to the GPIO pin of the MCU chip and is used to receive control signals for status indication.

2. The charge protection circuitry of claim 1, wherein: The reference voltage source is provided by a resistor divider network, which includes resistors R3 and R4, and the reference voltage is 1.65V.

3. The charge protection circuitry of claim 1, wherein: The signal conditioning circuit includes a π-type LC filter, the input of which is connected to the output of the operational amplifier circuit U1A, and the output of which is connected to the ADC pin of the MCU chip. The π-type LC filter includes an inductor L1, a capacitor C3, and a capacitor C4. An inductor L1 is provided between the output of the operational amplifier circuit U1A and the ADC pin of the MCU chip. The input and output of the inductor L1 are respectively connected to capacitors C3 and C4.

4. The charge protection circuitry of claim 3, wherein: The inductor L1 of the π-type LC filter has a value range of 10-100μH, and the capacitors C3 and C4 have a value range of 0.1-1μF. The cutoff frequency is ≤1kHz.

5. The charge protection circuitry of claim 1, wherein: The relay drive module also includes a freewheeling diode D3 connected in parallel across the coil of relay JK1. The anode of the freewheeling diode D3 is connected to the source of the MOS transistor Q1, and the cathode is connected to the power supply terminal of the relay JK1 coil.

6. The charge protection circuitry of claim 1, wherein: It also includes a serial communication module, which includes a level conversion chip U3 and a communication interface J1. The serial data transmission pin and the receiving pin of the level conversion chip U3 are respectively connected to the corresponding pins of the MCU chip.

7. The charge protection circuitry of claim 1, wherein: The status indicator module uses tri-color LEDs. In the common cathode or common anode connection mode of the tri-color LEDs, each color channel is connected to the corresponding GPIO pin of the MCU chip through an independent current-limiting resistor.

8. The charge protection circuitry of claim 1, wherein: The control module also includes an external EEPROM memory U2 connected to the MCU chip via an I²C bus, used to store system parameters, including normal current range threshold, standby current threshold, overcurrent protection threshold, and preset time parameters.

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