Acc output protection circuit for electric two-wheeler
By designing an ACC output protection circuit for electric two-wheelers, the problem of short circuit in the MOSFET at the ACC output terminal is solved by using a combination of output transistors and switching transistors and a dual overcurrent protection circuit. This achieves fast response and high reliability overcurrent protection, improving the stability and safety of the circuit.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGZHOU YADEA LOCOMOTIVE CO LTD
- Filing Date
- 2025-08-21
- Publication Date
- 2026-07-24
AI Technical Summary
The MOSFET at the ACC output terminal of electric two-wheeled vehicles is prone to short circuit faults, which can cause the vehicle to be unable to shut down or be armed, affecting its reliability and stability.
An ACC output protection circuit including an output circuit and a dual overcurrent protection circuit is designed. By combining the output transistor and the switching transistor, the output state is controlled by the enable signal. The first and second protection circuits reduce the voltage between the gate and source of the output transistor and turn off the switching transistor respectively during overcurrent, thereby achieving dual overcurrent protection.
It provides fast-response and highly reliable overcurrent protection, ensuring reliable operation of the circuit under abnormally high current, preventing short-circuit failure of the output MOSFET, and improving the stability and safety of the circuit.
Smart Images
Figure CN224555187U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power electronics, and in particular to an ACC output protection circuit for electric two-wheeled vehicles. Background Technology
[0002] With the acceleration of urbanization and the increasing awareness of environmental protection, two-wheeled electric vehicles can effectively solve the needs of short-distance traffic congestion and energy conservation and emission reduction, thus gaining widespread application. Traditional electric vehicle ignition switches supply power to some electrical devices through the ACC output terminal in the ACC position. However, the output MOSFET at the ACC output terminal is prone to short-circuit faults, causing the vehicle to fail to power off and become unarmed, reducing reliability and stability, and affecting safety. Utility Model Content
[0003] In response to the aforementioned problems and technical requirements, the applicant has proposed an ACC output protection circuit for electric two-wheeled vehicles.
[0004] The technical solution of this utility model is as follows:
[0005] An ACC output protection circuit for an electric two-wheeler includes an output circuit and an overcurrent protection circuit connected together, wherein...
[0006] The input terminal of the output circuit is electrically connected to the power supply, the output terminal of the output circuit is electrically connected to the ACC output terminal, and the enable terminal of the output circuit is connected to an enable signal, which is used to control the output state of the output circuit.
[0007] The overcurrent protection circuit includes a first protection circuit and a second protection circuit connected to each other, which are used to provide dual overcurrent protection for the output circuit.
[0008] A further technical solution is that the output circuit includes an output transistor Q1, a capacitor C2, a Zener diode DZ2, a diode D1, resistors R3, R4, R8, and R11, and a switching transistor Q3, wherein...
[0009] One end of capacitor C2 is connected to the first electrode of output transistor Q1 and the negative terminal of Zener diode DZ2 to form the input terminal of the output circuit. The other end of capacitor C2 is connected to the positive terminal of Zener diode DZ2, one end of resistor R11 and one end of resistor R3. The other end of resistor R11 is connected to the power supply. The other end of resistor R3 is connected to the second electrode of output transistor Q1. The third electrode of output transistor Q1 is connected to the positive terminal of diode D1.
[0010] The second electrode of the output transistor Q1 is connected to the third electrode of the switching transistor Q3. The first electrode of the switching transistor Q3 is grounded through resistor R8. The second electrode of the switching transistor Q3 is connected to one end of resistor R4. The other end of resistor R4 forms the enable terminal of the output circuit.
[0011] A further technical solution is that the enable signal controls the output state of the output circuit by controlling the conduction state of the output transistor Q1. When the enable signal is at an effective level, it controls the switching transistor Q3 to conduct in order to control the output transistor Q1 to conduct, so that the output circuit supplies power to the load connected to the ACC output terminal.
[0012] A further technical solution is that the output transistor Q1 is a PMOS transistor and the switching transistor Q3 is an NPN transistor.
[0013] A further technical solution is that the output circuit also includes a filter circuit, which includes a Zener diode DZ1 and a capacitor C1.
[0014] The negative terminal of diode D1 is connected to the negative terminal of Zener diode DZ1 and one end of capacitor C1 to form the output terminal of the output circuit. The positive terminal of Zener diode DZ1 is grounded, and the other end of capacitor C1 is grounded.
[0015] A further technical solution is that the first protection circuit is used to reduce the voltage between the gate and source of the output transistor Q1 when performing overcurrent protection, and the second protection circuit is used to turn off the switching transistor Q3 when performing overcurrent protection.
[0016] A further technical solution is that the first protection circuit includes resistors R1, R2, R5, R6, and R10, capacitor C3, switching transistor Q2, and switching transistor Q5, wherein...
[0017] One end of resistor R1 is connected to the power supply, and the other end of resistor R1 is connected to one end of resistor R2 and the input terminal of the output circuit. The other end of resistor R2 is connected to one end of capacitor C3, the third electrode of switching transistor Q2, and the second electrode of switching transistor Q5. The other end of capacitor C3 is connected to the power supply. The first electrode of switching transistor Q5 is connected to the power supply. The second electrode of switching transistor Q2 is connected to the third electrode of switching transistor Q5 through resistor R6. The third electrode of switching transistor Q5 is connected to the positive terminal of Zener diode DZ2 through resistor R10. The first electrode of switching transistor Q2 is grounded through resistor R5.
[0018] A further technical solution is that the switching transistor Q2 is an NPN transistor and the switching transistor Q5 is a PNP transistor.
[0019] A further technical solution is that the second protection circuit includes a switching transistor Q4, a resistor R7, and a resistor R9, wherein...
[0020] The first electrode of the switching transistor Q4 is grounded, the third electrode of the switching transistor Q4 is connected to the second electrode of the switching transistor Q3, the second electrode of the switching transistor Q4 is connected to one end of resistor R9 and one end of resistor R7, the other end of resistor R9 is grounded, and the other end of resistor R7 is connected to the third electrode of the switching transistor Q5.
[0021] A further technical solution is that the switching transistor Q4 is an NPN transistor.
[0022] The beneficial technical effects of this utility model are:
[0023] The ACC output protection circuit for electric two-wheeled vehicles provided by this utility model offers dual overcurrent protection and features fast response, high reliability, and high stability. It ensures reliable circuit operation even when there is an abnormally large current at the ACC output terminal. It effectively solves the problem of short-circuit failure of the output MOSFET caused by overload at the ACC output terminal or a large instantaneous current upon power-on. Attached Figure Description
[0024] Figure 1 This is a circuit diagram of one embodiment of the ACC output protection circuit for electric two-wheeled vehicles provided by this utility model. Detailed Implementation
[0025] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this disclosure.
[0026] This utility model provides an ACC output protection circuit for electric two-wheeled vehicles. Please refer to [reference needed]. Figure 1 The ACC output protection circuit includes an output circuit and an overcurrent protection circuit connected together. The input terminal of the output circuit is electrically connected to the power supply, and the output terminal of the output circuit is electrically connected to the ACC output terminal. An enable signal is connected to the enable terminal of the output circuit, and the enable signal is used to control the output state of the output circuit. The overcurrent protection circuit includes a first protection circuit and a second protection circuit connected together, which are used to provide dual overcurrent protection for the output circuit.
[0027] Specifically, the output circuit includes an output transistor Q1, a capacitor C2, a Zener diode DZ2, a diode D1, resistors R3, R4, R8, and R11, and a switching transistor Q3. One end of the capacitor C2 is connected to the first electrode of the output transistor Q1 and the negative terminal of the Zener diode DZ2, forming the input terminal of the output circuit. The other end of the capacitor C2 is connected to the positive terminal of the Zener diode DZ2, one end of resistor R11, and one end of resistor R3. The other end of resistor R11 is connected to the power supply. The other end of resistor R3 is connected to the second electrode of the output transistor Q1. The third electrode of the output transistor Q1 is connected to the positive terminal of the diode D1. The second electrode of the output transistor Q1 is connected to the third electrode of the switching transistor Q3. The first electrode of the switching transistor Q3 is grounded through resistor R8. The second electrode of the switching transistor Q3 is connected to one end of resistor R4. The other end of resistor R4 forms the enable terminal of the output circuit.
[0028] In this embodiment, the output transistor Q1 is a PMOS transistor, and the switching transistor Q3 is an NPN transistor. For the PMOS transistor, the first electrode is the source, the second electrode is the gate, and the third electrode is the drain. For the transistor (PNP and NPN types), the first electrode is the emitter, the second electrode is the base, and the third electrode is the collector. The power supply can be the battery of the electric two-wheeled vehicle, and the ACC output terminal is connected to the load, which can be the equipment in the electric two-wheeled vehicle that requires power.
[0029] When the output circuit is operating, the enable signal (ACC_EN) controls the output state of the output circuit by controlling the conduction state of the output transistor Q1. In the normal output state, the enable signal is at a high level. When the enable signal is at a high level, it turns on the switch transistor Q3 through resistor R4. Resistors R8, R3, and R11 form a voltage divider network, causing the gate voltage of the output transistor Q1 to drop. This results in the voltage between the gate and source of the output transistor Q1 being greater than the threshold voltage of Q1, thus controlling Q1 to conduct and forming an output path. The output circuit then supplies power to the load connected to the ACC output terminal. Conversely, when the enable signal is at a low level, the switch transistor Q3 is turned off, causing Q1 to turn off, and the output circuit does not form an output path. The values of resistors R8, R3, and R11 can be set according to actual conditions, ensuring that the voltage between the gate and source of the output transistor Q1 is greater than its threshold voltage when Q3 is on.
[0030] The capacitor C2 and Zener diode DZ2 are protective devices for the output transistor Q1, used to prevent damage to Q1 due to overvoltage. The diode D1 is used to prevent backflow at the ACC output terminal. The output circuit also includes a filter circuit, which includes a Zener diode DZ1 and a capacitor C1. The cathode of the diode D1 is connected to the cathode of the Zener diode DZ1 and one end of the capacitor C1, forming the output terminal of the output circuit. The anode of the Zener diode DZ1 is grounded, and the other end of the capacitor C1 is grounded. The filter circuit is used to filter the voltage output by the output circuit.
[0031] Furthermore, the dual overcurrent protection specifically refers to the following: the first protection circuit reduces the voltage between the gate and source of the output transistor Q1 during overcurrent protection, thereby turning off the output transistor Q1 and forming the first layer of protection; the second protection circuit turns off the switching transistor Q3 during overcurrent protection, thereby turning off the output transistor Q1 and forming the second layer of protection. The dual overcurrent protection can stably turn off the output transistor Q1 and cut off the output path when an overcurrent occurs in the circuit, improving the overall reliability and safety of the circuit.
[0032] Specifically, the first protection circuit includes resistors R1, R2, R5, R6, and R10, capacitor C3, switching transistor Q2, and switching transistor Q5. One end of resistor R1 is connected to the power supply, and the other end of resistor R1 is connected to one end of resistor R2 and the input terminal of the output circuit. The other end of resistor R2 is connected to one end of capacitor C3, the third electrode of switching transistor Q2, and the second electrode of switching transistor Q5. The other end of capacitor C3 is connected to the power supply. The first electrode of switching transistor Q5 is connected to the power supply. The second electrode of switching transistor Q2 is connected to the third electrode of switching transistor Q5 through resistor R6. The third electrode of switching transistor Q5 is connected to the positive terminal of Zener diode DZ2 through resistor R10. The first electrode of switching transistor Q2 is grounded through resistor R5.
[0033] The second protection circuit includes a switching transistor Q4, resistors R7 and R9. The first electrode of switching transistor Q4 is grounded, the third electrode of switching transistor Q4 is connected to the second electrode of switching transistor Q3, the second electrode of switching transistor Q4 is connected to one end of resistor R9 and one end of resistor R7, the other end of resistor R9 is grounded, and the other end of resistor R7 is connected to the third electrode of switching transistor Q5. In this embodiment, switching transistor Q2 is an NPN transistor, switching transistor Q5 is a PNP transistor, and switching transistor Q4 is an NPN transistor. The transistors have a millisecond-level response speed, enabling the overcurrent protection circuit to have a fast response capability. When the switching transistor is a transistor, the definitions of the first to third electrodes of the switching transistor are consistent with the above, and will not be repeated here.
[0034] The specific working principle of the overcurrent protection current is as follows: Resistor R1 acts as a current sampling resistor. When the current flowing through it exceeds the set threshold, the voltage difference across resistor R1 causes switch Q5 to conduct through resistor R2. Capacitor C3 is a filter capacitor used to prevent instantaneous spike current from causing false turn-on of switch Q5. After Q5 conducts, the high voltage of the power supply is applied to the gate of output transistor Q1 through resistors R10 and R3. The resistance value of resistor R10 is set to a small value so that after switch Q3 conducts, the voltage between the gate and source of output transistor Q1 is less than the threshold voltage, causing output transistor Q1 to turn off, disconnecting the output path, and forming the first level of ACC output protection. The high voltage of the power supply also causes switch Q2 to conduct through resistor R6, which pulls down the base voltage of switch Q5, keeping switch Q5 continuously conducting, forming an interlock. At the same time, the high voltage of the power supply causes switch Q4 to conduct through resistor R7, which pulls down the base voltage of switch Q3. When switch Q3 turns off, output transistor Q1 turns off, forming the second level of ACC output protection. The set threshold can be set according to actual needs, and the resistance value of resistor R10 can also be set according to actual conditions. It is sufficient to meet the functional requirement that when performing overcurrent protection, the high voltage of the power supply is applied to the gate of the output transistor Q1 through resistor R10 and resistor R3, so that the output transistor Q1 is turned off.
[0035] In the description of this specification, the reference to the term "an embodiment / method" means that a specific feature, structure, or characteristic described in connection with that embodiment / method is included in at least one embodiment / method of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / method.
[0036] The above descriptions are merely preferred embodiments of the present invention, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations that can be directly derived or conceived by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included within the protection scope of the present invention.
Claims
1. An ACC output protection circuit for an electric two-wheeled vehicle, characterized in that, This includes the connected output circuit and the overcurrent protection circuit, wherein, The input terminal of the output circuit is electrically connected to the power supply, the output terminal of the output circuit is electrically connected to the ACC output terminal, and the enable terminal of the output circuit is connected to an enable signal, which is used to control the output state of the output circuit. The overcurrent protection circuit includes a first protection circuit and a second protection circuit connected to each other, which are used to provide dual overcurrent protection for the output circuit.
2. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 1, characterized in that, The output circuit includes an output transistor Q1, a capacitor C2, a Zener diode DZ2, a diode D1, resistors R3, R4, R8, and R11, and a switching transistor Q3. One end of capacitor C2 is connected to the first electrode of output transistor Q1 and the negative terminal of Zener diode DZ2 to form the input terminal of the output circuit. The other end of capacitor C2 is connected to the positive terminal of Zener diode DZ2, one end of resistor R11 and one end of resistor R3. The other end of resistor R11 is connected to the power supply. The other end of resistor R3 is connected to the second electrode of output transistor Q1. The third electrode of output transistor Q1 is connected to the positive terminal of diode D1. The second electrode of the output transistor Q1 is connected to the third electrode of the switching transistor Q3. The first electrode of the switching transistor Q3 is grounded through resistor R8. The second electrode of the switching transistor Q3 is connected to one end of resistor R4. The other end of resistor R4 forms the enable terminal of the output circuit.
3. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 2, characterized in that, The enable signal controls the output state of the output circuit by controlling the conduction state of the output transistor Q1. When the enable signal is at an effective level, it controls the switching transistor Q3 to conduct in order to control the output transistor Q1 to conduct, so that the output circuit supplies power to the load connected to the ACC output terminal.
4. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 3, characterized in that, The output transistor Q1 is a PMOS transistor, and the switching transistor Q3 is an NPN transistor.
5. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 2, characterized in that, The output circuit also includes a filter circuit, which includes a Zener diode DZ1 and a capacitor C1. The negative terminal of diode D1 is connected to the negative terminal of Zener diode DZ1 and one end of capacitor C1 to form the output terminal of the output circuit. The positive terminal of Zener diode DZ1 is grounded, and the other end of capacitor C1 is grounded.
6. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 3, characterized in that, The first protection circuit is used to reduce the voltage between the gate and source of the output transistor Q1 when performing overcurrent protection, and the second protection circuit is used to turn off the switching transistor Q3 when performing overcurrent protection.
7. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 2, characterized in that, The first protection circuit includes resistors R1, R2, R5, R6, and R10, capacitor C3, switching transistor Q2, and switching transistor Q5, wherein... One end of resistor R1 is connected to the power supply, and the other end of resistor R1 is connected to one end of resistor R2 and the input terminal of the output circuit. The other end of resistor R2 is connected to one end of capacitor C3, the third electrode of switching transistor Q2, and the second electrode of switching transistor Q5. The other end of capacitor C3 is connected to the power supply. The first electrode of switching transistor Q5 is connected to the power supply. The second electrode of switching transistor Q2 is connected to the third electrode of switching transistor Q5 through resistor R6. The third electrode of switching transistor Q5 is connected to the positive terminal of Zener diode DZ2 through resistor R10. The first electrode of switching transistor Q2 is grounded through resistor R5.
8. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 7, characterized in that, The switching transistor Q2 is an NPN transistor, and the switching transistor Q5 is a PNP transistor.
9. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 7, characterized in that, The second protection circuit includes a switch Q4, a resistor R7, and a resistor R9, wherein, The first electrode of the switching transistor Q4 is grounded, the third electrode of the switching transistor Q4 is connected to the second electrode of the switching transistor Q3, the second electrode of the switching transistor Q4 is connected to one end of resistor R9 and one end of resistor R7, the other end of resistor R9 is grounded, and the other end of resistor R7 is connected to the third electrode of the switching transistor Q5.
10. The ACC output protection circuit for an electric two-wheeled vehicle according to claim 9, characterized in that, The switching transistor Q4 is an NPN transistor.