Overcurrent protection circuit for two-wheeled electric vehicle

Abstract

The utility model discloses an overcurrent protection circuit for a two-wheeled electric vehicle, which relates to the field of electronic circuits and comprises a switch, a switch driving circuit, an output protection current setting circuit, a signal comparison circuit, a protection self-locking circuit and an optional microcontroller circuit. Wherein the protection self-locking circuit is connected with the switch and switch driving circuit, the output protection current setting circuit and the signal comparison circuit, the switch and switch driving circuit is connected with the output protection current setting circuit, and the output protection current setting circuit is connected with the signal comparison circuit. According to the utility model, the instrument of the two-wheeled electric vehicle cannot be burnt out after the load current is too large or even short circuit occurs, the use safety of customers is improved, the after-sales cost is reduced, and the two-wheeled electric vehicle is lower in carbon and more environment-friendly.

Description

Technical Field

[0001] This utility model relates to the field of electronic circuits, specifically to an overcurrent protection circuit for a two-wheeled electric vehicle. Background Technology

[0002] Two-wheeled electric vehicles or e-bikes are a type of transportation that combines electric power with human pedaling. These electric vehicles primarily rely on an electric motor for power, but can also be propelled by the rider's leg strength.

[0003] Traditionally, e-bikes used a combination of an instrument panel and a drive module to power components such as headlights, taillights, and turn signals. However, with increasing competition, cost considerations have led to the removal of the drive module, making it a trend for the e-bike's instrument panel to directly drive these components.

[0004] When the load current is too high and exceeds the load capacity of the electric bicycle's instrument panel, or when the external load seal ages or water gets in and causes a short circuit, the instrument panel will be damaged, posing a safety hazard to the customer. Moreover, replacing the instrument panel requires a lot of manpower and resources, resulting in high after-sales costs.

[0005] No effective solutions have yet been proposed to address the problems in the relevant technologies. Utility Model Content

[0006] In view of the problems in the related technologies, this utility model proposes an overcurrent protection circuit for two-wheeled electric vehicles to overcome the above-mentioned technical problems existing in the existing related technologies.

[0007] Therefore, the specific technical solution adopted by this utility model is as follows:

[0008] An overcurrent protection circuit for a two-wheeled electric vehicle includes a switch and a switch drive circuit, an output protection current setting circuit, a signal comparison circuit, and a protection self-locking circuit. The protection self-locking circuit is connected to the switch and the switch drive circuit, the output protection current setting circuit, and the signal comparison circuit. The switch and the switch drive circuit are connected to the output protection current setting circuit, and the output protection current setting circuit is connected to the signal comparison circuit.

[0009] Furthermore, the switch and switch driving circuit include diode D1, MOSFET Q1, resistors R1, R2, R3, R4, and transistor Q2; wherein, the cathode of diode D1 is connected in sequence to one end of resistor R1 and the source of MOSFET Q1, the anode of diode D1 is connected in sequence to the other end of resistor R1, the gate of MOSFET Q1, and one end of resistor R2, the other end of resistor R2 is connected to the first end of transistor Q2, the third end of transistor Q2 is connected in sequence to one end of resistor R3 and one end of resistor R4, the second end of transistor Q2 is connected to the protection self-locking circuit 4, and the drain of MOSFET Q1 is connected to the output protection current setting circuit.

[0010] Furthermore, the output protection current setting circuit 2 includes resistors R5, R6, R7, R8, R9, and R10; wherein, one end of resistor R5 is connected in sequence to the switch and the switch driving circuit and one end of resistor R6, and the other end of resistor R5 is connected in sequence to resistor R8 and the output terminal; the other end of resistor R6 is connected in sequence to one end of resistor R7, the protection self-locking circuit, and the signal comparison circuit, and the other end of resistor R8 is connected in sequence to one end of resistor R9, one end of resistor R10, and the signal comparison circuit.

[0011] Furthermore, the signal comparison circuit includes an operational amplifier chip U7B and a resistor R12; wherein, the fifth and sixth terminals of the operational amplifier chip U7B are both connected to the output protection current setting circuit, and the seventh terminal of the operational amplifier chip U7B is connected in sequence to one end of the resistor R12 and the protection self-locking circuit.

[0012] Furthermore, the protection self-locking circuit includes diode D2 and resistor R13; wherein, the negative terminal of diode D2 is connected to the output protection current setting circuit, the positive terminal of diode D2 is connected to one end of resistor R13, and the other end of resistor R13 is connected in sequence to the switch, the switch driving circuit, and the signal comparison circuit.

[0013] Optionally, the overcurrent protection circuit for the two-wheeled electric vehicle also includes a microcontroller circuit, which includes GPIO1 pin and GPIO2 pin. GPIO1 pin is connected to the switch drive circuit, and GPIO2 pin is connected to the protection self-locking circuit.

[0014] The beneficial effects of this utility model are as follows:

[0015] This invention achieves the effect of preventing the instrument panel of a two-wheeled electric vehicle from burning out even when the load current is too high or there is a short circuit, thus improving customer safety, reducing after-sales costs, and being more low-carbon and environmentally friendly. The switch drive circuit controls the main switch and drive circuit that controls the output of the instrument to the load; the output protection current setting circuit converts the current signal output by the instrument into a voltage signal and sets the threshold of the output protection current; the signal comparison circuit shuts off the external output of the instrument when the output current exceeds the set threshold of the output protection current; and the protection self-locking circuit cuts off the external output circuit after entering the protection state. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of an overcurrent protection circuit for a two-wheeled electric vehicle according to Embodiment 1 of this utility model;

[0018] Figure 2 This is a schematic diagram of an overcurrent protection circuit for a two-wheeled electric vehicle according to Embodiment 2 of this utility model;

[0019] Figure 3 This is an overall structural framework diagram according to an embodiment of the present utility model.

[0020] In the picture:

[0021] 1. Switch and switch drive circuit; 2. Output protection current setting circuit; 3. Signal comparison circuit; 4. Protection self-locking circuit; 5. Microcontroller circuit. Detailed Implementation

[0022] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0023] According to an embodiment of the present invention, an overcurrent protection circuit for a two-wheeled electric vehicle is provided.

[0024] Example 1

[0025] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figure 1 As shown, the overcurrent protection circuit for a two-wheeled electric vehicle according to an embodiment of the present invention includes a switch and a switch driving circuit 1, an output protection current setting circuit 2, a signal comparison circuit 3, and a protection self-locking circuit 4. The protection self-locking circuit 4 is connected to the switch and the switch driving circuit 1, the output protection current setting circuit 2, and the signal comparison circuit 3. The switch and the switch driving circuit 1 is connected to the output protection current setting circuit 2, and the output protection current setting circuit 2 is connected to the signal comparison circuit 3.

[0026] With the above solution, this utility model achieves the effect of not burning out the instrument panel of a two-wheeled electric vehicle after excessive load current or even short circuit, improving the safety of customers during use, reducing after-sales costs, and being more low-carbon and environmentally friendly.

[0027] In one embodiment, the switch and switch driving circuit 1 include a diode D1, a MOSFET Q1, resistors R1, R2, R3, and R4, and a transistor Q2. The cathode of diode D1 is connected sequentially to one end of resistor R1 and the source of MOSFET Q1; the anode of diode D1 is connected sequentially to the other end of resistor R1, the gate of MOSFET Q1, and one end of resistor R2; the other end of resistor R2 is connected to the first end of transistor Q2; the third end of transistor Q2 is connected sequentially to one end of resistor R3 and one end of resistor R4; the second end of transistor Q2 is connected to a protection latching circuit 4; and the drain of MOSFET Q1 is connected to an output protection current setting circuit 2. When the switch and switch driving circuit 1 is open, it can output discharge externally; when closed, it cuts off external output discharge.

[0028] In one embodiment, the output protection current setting circuit 2 includes resistors R5, R6, R7, R8, R9, and R10. One end of resistor R5 is sequentially connected to the switch drive circuit 1 and one end of resistor R6; the other end of resistor R5 is sequentially connected to the output terminal and one end of resistor R8. The other end of resistor R6 is sequentially connected to one end of resistor R7, the protection self-locking circuit 4, and the signal comparison circuit 3; the other end of resistor R8 is sequentially connected to one end of resistor R9, one end of resistor R10, and the signal comparison circuit 3. The output protection current setting circuit 2 sets the maximum current threshold for the instrument's output and converts it into different voltage signals.

[0029] In one embodiment, the signal comparison circuit 3 includes an operational amplifier chip U7B and a resistor R12; wherein, the fifth and sixth terminals of the operational amplifier chip U7B are both connected to the output protection current setting circuit 2, and the seventh terminal of the operational amplifier chip U7B is sequentially connected to one end of the resistor R12 and the protection self-locking circuit 4. The signal comparison circuit 3 compares the actual output current with the maximum safe current. If the actual output current is greater than the maximum safe current, the main output switch is turned off; if the actual output current is less than the maximum safe current, the main output switch is turned on or off depending on the state required by the instrument; in both cases, the optional microcontroller circuit 5 is notified.

[0030] In one embodiment, the protection self-locking circuit 4 includes a diode D2 and a resistor R13; wherein, the cathode of diode D2 is connected to the output protection current setting circuit 2, the anode of diode D2 is connected to one end of resistor R13, and the other end of resistor R13 is connected in sequence to the switch and switch drive circuit 1 and signal comparison circuit 3. When overcurrent protection occurs and the main output switch is turned off, the protection self-locking circuit 4 locks the protection state.

[0031] Example 2

[0032] like Figure 2 As shown, for the overcurrent protection circuit of the above-mentioned two-wheeled electric vehicle, the overcurrent protection circuit of the two-wheeled electric vehicle can also adopt the following structure to achieve the effect of not burning out the instrument of the two-wheeled electric vehicle after the load current is too large or even short circuit, thereby improving the safety of customers during use, reducing after-sales costs, and having the advantages of being more low-carbon and environmentally friendly. The overcurrent protection circuit of the two-wheeled electric vehicle includes a switch and switch drive circuit 1, an output protection current setting circuit 2, a signal comparison circuit 3, a protection self-locking circuit 4, and a microcontroller circuit 5; the protection self-locking circuit 4 is connected to the switch and switch drive circuit 1, the output protection current setting circuit 2, and the signal comparison circuit 3; the switch and switch drive circuit 1 is connected to the output protection current setting circuit 2; the output protection current setting circuit 2 is connected to the protection self-locking circuit 4; the microcontroller circuit 5 is connected to the switch and switch drive circuit 1 and the signal comparison circuit 3.

[0033] In one embodiment, the microcontroller circuit 5 includes a GPIO1 pin and a GPIO2 pin. The GPIO1 pin is connected to the switch driver circuit 1, and the GPIO2 pin is connected to the protection latching circuit 4. Optionally, the microcontroller circuit 5 reads the actual protection status and displays a corresponding prompt on the screen. Optionally, the microcontroller circuit 5 can also detect whether the overcurrent abnormality has been resolved by attempting to open the output circuit. If the overcurrent condition has been resolved, the normal output state can be restored without power-off restart.

[0034] To facilitate understanding of the above technical solutions of this utility model, the working principle of this utility model in actual process will be described in detail below.

[0035] This invention incorporates current sampling technology, analog voltage setting technology, small-signal comparison technology, signal self-locking technology, and optional microcontroller technology. Through a switch and switch drive circuit 1, an output protection current setting circuit 2, a signal comparison circuit 3, a protection self-locking circuit 4, and an optional microcontroller circuit 5, it adapts to the different current requirements of various electrical products (two-wheeled electric vehicles), providing users with higher safety, lower after-sales costs, and truly achieving low-carbon and environmentally friendly requirements.

[0036] This utility model is based on current detection to perform power supply output overcurrent protection circuit, including a switch and switch driving circuit 1 connected to the output main circuit, a current sampling resistor R5, an output protection current setting circuit 2, a signal comparison circuit 3, a protection self-locking circuit 4, and an optional microcontroller circuit 5.

[0037] The output protection current setting circuit 2 samples the actual output current through the current sampling resistor R5, and then converts it into two different voltage signals through voltage divider resistors of different ratios, which are then sent to the signal comparison circuit 3. The resistance value of the current sampling resistor R5 and the different ratios of the two voltage dividers determine the setting threshold of the output protection current. When the actual output current is greater than the setting threshold of the output protection current, the signal comparison circuit 3 outputs a high level, and the drive circuit of the output master switch is in the off state, thereby turning off the output master switch.

[0038] When the signal comparison circuit 3 outputs a high level, the presence of the protection self-locking circuit 4 will keep the output of the signal comparison circuit 3 at a high level. Even if the overcurrent condition disappears, the protection circuit will still keep the output main switch closed, thus realizing the protection state self-locking function.

[0039] When the output status of signal comparison circuit 3 is connected to optional microcontroller circuit 5, optional microcontroller circuit 5 determines whether to display a warning message on the screen. Only when optional microcontroller circuit 5 confirms that the overcurrent condition does not exist can it decide whether to open the output switch circuit and restore the external discharge output according to the state required by the instrument.

[0040] This invention features a simple circuit structure, employs pure hardware control, and boasts fast response speed and high reliability.

[0041] Functional descriptions of each circuit:

[0042] Switch and switch drive circuit 1: The main switch and its drive for controlling the output of the instrument to the load.

[0043] Output protection current setting circuit 2: The current sampling resistor R5 converts the current signal output by the instrument into a voltage signal. By using different voltage division ratios of the voltage divider circuit and the resistance value of the sampling resistor, the threshold value of the output protection current is set and then sent to the signal comparison circuit 3.

[0044] Signal comparison circuit 2: If the output current is greater than the set output protection current threshold, the instrument's external output is turned off; if the output current is less than the set output protection current threshold, the instrument's external output is turned on or off depending on the instrument's required state. Simultaneously, the comparison result is sent to the optional microcontroller circuit 5.

[0045] Protection self-locking and restart circuit 4: After entering the protection state, the external output circuit is cut off. Even if the overcurrent condition is removed, the protection state can still be maintained.

[0046] Self-locking protection circuit 4: This invention is implemented entirely in hardware and can independently achieve overcurrent protection without an optional microcontroller. If fault indication is required on the instrument display screen, the optional microcontroller circuit 5 is needed to read the signal given by the comparison circuit and display the relevant indication on the screen. If fault indication is not required, the optional microcontroller circuit 5 can be omitted.

[0047] Depending on the product requirements, an instrument may contain one or more output terminals and overcurrent protection circuits; the overcurrent protection circuit for medium and low speed electric vehicle instruments may be used for products with similar functions, including but not limited to instruments for three-wheeled electric vehicles, golf carts, and delivery vehicles.

[0048] like Figure 3 As shown, in practical applications, this utility model is also connected to the instrument power supply, load, instrument display part, etc. Figure 3 The structure within the dashed line is within the scope of this utility model.

[0049] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An overcurrent protection circuit for a two-wheeled electric vehicle, characterized in that, Includes a switch and switch drive circuit (1), an output protection current setting circuit (2), a signal comparison circuit (3), and a protection self-locking circuit (4). The protection self-locking circuit (4) is connected to the switch and switch driving circuit (1), the output protection current setting circuit (2) and the signal comparison circuit (3). The switch and switch driving circuit (1) is connected to the output protection current setting circuit (2), and the output protection current setting circuit (2) is connected to the signal comparison circuit (3). The output protection current setting circuit (2) includes resistors R5, R6, R7, R8, R9, and R10; wherein, one end of resistor R5 is connected in sequence to the switch and switch driving circuit (1) and one end of resistor R6, and the other end of resistor R5 is connected in sequence to the output terminal and one end of resistor R8; the other end of resistor R6 is connected in sequence to one end of resistor R7, the protection self-locking circuit (4), and the signal comparison circuit (3), and the other end of resistor R8 is connected in sequence to one end of resistor R9, one end of resistor R10, and the signal comparison circuit (3); The protection self-locking circuit (4) includes a diode D2 and a resistor R13; wherein, the negative terminal of the diode D2 is connected to the output protection current setting circuit (2), the positive terminal of the diode D2 is connected to one end of the resistor R13, and the other end of the resistor R13 is connected to the switch and switch driving circuit (1) and the signal comparison circuit (3) in sequence.

2. The overcurrent protection circuit for a two-wheeled electric vehicle according to claim 1, characterized in that, The switch and switch driving circuit (1) includes diode D1, MOSFET Q1, resistor R1, resistor R2, resistor R3, resistor R4 and transistor Q2; The negative terminal of diode D1 is connected to one end of resistor R1 and the source of MOSFET Q1 in sequence. The positive terminal of diode D1 is connected to the other end of resistor R1, the gate of MOSFET Q1 and one end of resistor R2 in sequence. The other end of resistor R2 is connected to the first end of transistor Q2. The third end of transistor Q2 is connected to one end of resistor R3 and one end of resistor R4 in sequence. The second end of transistor Q2 is connected to the protection self-locking circuit (4). The drain of MOSFET Q1 is connected to the output protection current setting circuit (2).

3. The overcurrent protection circuit for a two-wheeled electric vehicle according to claim 1, characterized in that, The signal comparison circuit (3) includes an operational amplifier chip U7B and a resistor R12; The fifth and sixth terminals of the operational amplifier chip U7B are connected to the output protection current setting circuit (2), and the seventh terminal of the operational amplifier chip U7B is connected to one end of the resistor R12 and the protection self-locking circuit (4) in sequence.

4. The overcurrent protection circuit for a two-wheeled electric vehicle according to claim 1, characterized in that, It also includes a microcontroller circuit (5), which includes a GPIO1 pin and a GPIO2 pin. The GPIO1 pin is connected to the switch and the switch driving circuit (1), and the GPIO2 pin is connected to the protection self-locking circuit (4).

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