A brushless motor controller

Abstract

The invention discloses a brushless motor controller, which relates to the field of motors. The brushless motor controller comprises: a motor working unit, which is used for, after receiving a PWM signal, turning on the circuit where the brushless motor is located, so that the brushless motor is powered on and works; an automatic current leakage control unit, which is used for detecting changes in the PWM signal, and controlling the brushless motor to ground leakage when the amplitude of the reduction of the duty cycle of the PWM signal exceeds a threshold within a set time; compared with the prior art, the beneficial effects of the invention are as follows: the invention automatically controls the motor leakage based on the change of the PWM signal after the PWM signal is disconnected by setting an automatic current leakage control unit, so that the energy stored in the motor is discharged in time, and damage to the motor and circuit components is avoided; a current leakage indication unit is designed, which indicates when the motor is leaking, so as to help confirm the working state of the motor; and an indication detection unit is designed, which verifies whether the current leakage indication unit is abnormal through a simple device.

Description

Technical Field

[0001] The invention relates to the field of motors, and in particular to a brushless motor controller. Background Art

[0002] The brushless DC motor is a typical mechatronics product, consisting of a motor body and a driver. The commutation function of the motor is achieved through electronic commutation technology.

[0003] In brushless DC motors, relevant protection circuits are often set up, such as stall protection, phase loss protection, overvoltage protection, undervoltage protection, temperature protection, overcurrent protection, etc. When the protection is triggered, the working circuit of the motor is often disconnected by disconnecting the PWM signal.

[0004] It should be noted that when the protection circuit triggers the motor to stop working, the energy stored in the motor is not discharged in time, and there is a possibility of damage to the motor and circuit components, which needs to be improved. Summary of the invention

[0005] The object of the present invention is to provide a brushless motor controller to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A brushless motor controller, comprising:

[0008] The motor working unit is used to connect the circuit of the brushless motor after receiving the PWM signal, so that the brushless motor is powered on and works;

[0009] Automatic leakage control unit, used to detect the change of PWM signal, and control the brushless motor to ground leakage when the amplitude of the duty cycle reduction of PWM signal exceeds the threshold within the set time;

[0010] A leakage current indicating unit, used to indicate the ground leakage current of the brushless motor;

[0011] An indication detection unit, used to control the operation of the leakage indication unit through a manual switch;

[0012] The output end of the motor working unit is connected to the input end of the automatic leakage control unit, and the output end of the automatic leakage control unit is connected to the input end of the leakage indication unit and the output end of the indication detection unit.

[0013] As a further solution of the present invention: the motor working unit includes a first resistor, a first metal-oxide semiconductor field effect transistor, and a brushless motor, one end of the first resistor is connected to the power supply voltage, the other end of the first resistor is connected to the drain of the first metal-oxide semiconductor field effect transistor, the source of the first metal-oxide semiconductor field effect transistor is connected to the input end of the automatic current discharge control unit and one end of the brushless motor, the other end of the brushless motor is grounded, and the gate of the first metal-oxide semiconductor field effect transistor introduces a PWM signal.

[0014] As a further solution of the present invention: the automatic leakage control unit includes a second crystal diode, a second capacitor, a second resistor, a third crystal diode, a fourth crystal diode, a third resistor, a fourth resistor, a third capacitor, a first amplifier, a second metal-oxide semiconductor field effect transistor, and a first crystal diode. The positive electrode of the second crystal diode introduces a PWM signal, the negative electrode of the second crystal diode is connected to one end of the second capacitor, one end of the second resistor, the positive electrode of the third crystal diode, and the positive electrode of the fourth crystal diode. The other end of the second capacitor is grounded, the other end of the second resistor is grounded, the negative electrode of the third crystal diode is connected to one end of the third resistor, and the other end of the third resistor is connected to the positive electrode of the third capacitor. The cathode of the fourth crystal diode is connected to one end of the fourth resistor, the other end of the fourth resistor is connected to the non-inverting end of the first amplifier, the output end of the first amplifier is connected to the gate of the second metal-oxide semiconductor field effect transistor, the source of the second metal-oxide semiconductor field effect transistor is connected to the cathode of the first crystal diode, the anode of the first crystal diode is connected to the output end of the motor working unit, the drain of the second metal-oxide semiconductor field effect transistor is connected to the input end of the leakage indication unit and the output end of the indication detection unit, the third resistor and the fourth resistor have equal resistance values, and the third crystal diode and the fourth crystal diode are crystal diodes of the same model.

[0015] As a further solution of the present invention: the leakage indication unit includes a second optical coupler, a fifth resistor, a sixth resistor, a seventh resistor, a third transistor, a fourth metal-oxide semiconductor field effect transistor, an eighth resistor, a first capacitor, a third voice chip, a fifth crystal diode, and a sixth crystal diode. The first end of the second optical coupler is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit. The second end of the second optical coupler is grounded. The third end of the second optical coupler is connected to one end of the fifth resistor. The other end of the fifth resistor is connected to the power supply voltage. The fourth end of the second optical coupler is connected to one end of the sixth resistor. The other end of the sixth resistor is connected to the base of the third transistor. The collector of the third transistor is connected to one end of the seventh resistor, the other end of the seventh resistor is connected to the power supply voltage, the emitter of the third transistor is connected to the gate of the fourth metal-oxide semiconductor field effect transistor, the drain of the fourth metal-oxide semiconductor field effect transistor is connected to the power supply voltage, the source of the fourth metal-oxide semiconductor field effect transistor is connected to one end of the eighth resistor, the other end of the eighth resistor is connected to one end of the first capacitor, one end of the voice chip, and the cathode of the sixth crystal diode, the other end of the first capacitor is grounded, the other end of the voice chip is connected to the anode of the sixth crystal diode and the anode of the fifth crystal diode, and the cathode of the fifth crystal diode is grounded.

[0016] As a further solution of the present invention: the leakage indication unit includes a fifth crystal diode, the anode of the fifth crystal diode is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit, and the cathode of the fifth crystal diode is grounded.

[0017] As a further solution of the present invention: the leakage indication unit includes a third voice chip, one end of the third voice chip is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit, and the other end of the third voice chip is grounded.

[0018] As a further solution of the present invention: the indication detection unit includes a ninth resistor and a first switch, one end of the ninth resistor is connected to the power supply voltage, the other end of the ninth resistor is connected to one end of the first switch, and the other end of the first switch is connected to the output end of the automatic leakage control unit and the input end of the leakage indication unit.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention sets an automatic leakage control unit, which automatically controls the motor leakage based on the change of the PWM signal after the PWM signal is disconnected, so that the energy stored in the motor is discharged in time to avoid damage to the motor and circuit components; the leakage indication unit is designed to indicate when the motor is leaking, helping to confirm the working status of the motor; the indication detection unit is designed to verify whether the leakage indication unit is abnormal through simple devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The schematic diagram of a brushless motor controller.

[0021] Figure 2 The first embodiment of the circuit diagram of a brushless motor controller is shown in FIG.

[0022] Figure 3 The circuit diagram of the second embodiment of a brushless motor controller is shown in FIG.

[0023] Figure 4 The third embodiment is a circuit diagram of a brushless motor controller. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] See also Figure 1 , a brushless motor controller, comprising:

[0026] The motor working unit 1 is used to connect the circuit of the brushless motor M after receiving the PWM signal, so that the brushless motor M is powered on and works;

[0027] The automatic leakage control unit 2 is used to detect the change of the PWM signal, and when the amplitude of the duty cycle reduction of the PWM signal exceeds a threshold within a set time, the brushless motor M is controlled to be grounded for leakage;

[0028] A leakage current indicating unit 3, used for indicating the ground leakage current of the brushless motor M;

[0029] The indication detection unit 4 is used to control the leakage indication unit 3 to work through a manual switch;

[0030] The output end of the motor working unit 1 is connected to the input end of the automatic leakage control unit 2 , and the output end of the automatic leakage control unit 2 is connected to the input end of the leakage indication unit 3 and the output end of the indication detection unit 4 .

[0031] In this example: See Figure 2 or Figure 3 or Figure 4The motor working unit 1 includes a first resistor R1, a first metal-oxide semiconductor field effect transistor V1, and a brushless motor M. One end of the first resistor R1 is connected to the power supply voltage VCC, the other end of the first resistor R1 is connected to the drain of the first metal-oxide semiconductor field effect transistor V1, the source of the first metal-oxide semiconductor field effect transistor V1 is connected to the input end of the automatic leakage control unit 2 and one end of the brushless motor M, the other end of the brushless motor M is grounded, and the gate of the first metal-oxide semiconductor field effect transistor V1 introduces a PWM signal.

[0032] The power supply voltage VCC is input and transmitted to the drain of the first metal-oxide semiconductor field effect transistor V1 through the first resistor R1. When the PWM signal is input to the gate of the first metal-oxide semiconductor field effect transistor V1, the first metal-oxide semiconductor field effect transistor V1 is turned on. The power supply voltage VCC is grounded through the first resistor R1, the first metal-oxide semiconductor field effect transistor V1, and the brushless motor M. The brushless motor M is powered on and works. The conduction frequency of the first metal-oxide semiconductor field effect transistor V1 is adjusted by adjusting the duty cycle of the PWM signal to change the current flowing through the brushless motor M to adjust the rotation speed of the brushless motor M.

[0033] In another embodiment: the PWM signal can be obtained through a hardware PWM generator or generated by software simulation; many microcontrollers and DSPs (digital signal processors) have built-in hardware PWM generators that can directly generate adjustable PWM signals. By configuring the relevant registers of the PWM generator, the frequency, duty cycle and other parameters of the PWM signal can be set; software simulates PWM, and generates PWM signals through timer interrupts or loop checking time. Although it is less efficient than a hardware PWM generator, it can implement more complex control logic.

[0034] In this example: See Figure 2 or Figure 3 or Figure 4The automatic leakage control unit 2 includes a second crystal diode D2, a second capacitor C2, a second resistor R2, a third crystal diode D3, a fourth crystal diode D4, a third resistor R3, a fourth resistor R4, a third capacitor C3, a first amplifier U1, a second metal-oxide semiconductor field effect transistor V2, and a first crystal diode D1. The positive electrode of the second crystal diode D2 introduces the PWM signal, the negative electrode of the second crystal diode D2 is connected to one end of the second capacitor C2, one end of the second resistor R2, the positive electrode of the third crystal diode D3, and the positive electrode of the fourth crystal diode D4. The other end of the second capacitor C2 is grounded, the other end of the second resistor R2 is grounded, the negative electrode of the third crystal diode D3 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is connected to the positive electrode of the third capacitor C3. The cathode of the fourth crystal diode D4 is connected to one end of the fourth resistor R4, the other end of the fourth resistor R4 is connected to the non-inverting end of the first amplifier U1, the output end of the first amplifier U1 is connected to the gate of the second metal-oxide semiconductor field effect transistor V2, the source of the second metal-oxide semiconductor field effect transistor V2 is connected to the cathode of the first crystal diode D1, the anode of the first crystal diode D1 is connected to the output end of the motor working unit 1, the drain of the second metal-oxide semiconductor field effect transistor V2 is connected to the input end of the leakage indication unit 3 and the output end of the indication detection unit 4, the third resistor R3 and the fourth resistor R4 have equal resistance values, and the third crystal diode D3 and the fourth crystal diode D4 are crystal diodes of the same model.

[0035] The protection circuits such as stall protection, phase loss protection, overvoltage protection, undervoltage protection, temperature protection, and overcurrent protection in the brushless motor circuit (it is a common technology to set up protection circuits in equipment, which will not be introduced in detail here) often disconnect the PWM signal when the protection is triggered. Before the protection is triggered, the brushless motor M is already in an abnormal working state. Therefore, after the PWM signal is disconnected, the energy stored in the brushless motor M is released in time, which can avoid damage to the brushless motor M and circuit components; after the PWM signal is input, it is rectified and filtered by the crystal diode D2 and the capacitor C2 to form a stable voltage signal on the second resistor R2, and the voltage signal corresponding to the current PWM signal is sent to the in-phase end of the first amplifier U1 through the fourth crystal diode D4 and the fourth resistor R4, and the voltage is delayed through the third crystal diode D3, the third resistor R3, and the third capacitor C3, and the voltage signal corresponding to the delayed PWM signal is sent to the inverting end of the first amplifier U1. That is, the in-phase end of the first amplifier U1 is the voltage corresponding to the current PWM signal, and the inverting end of the first amplifier U1 is the voltage corresponding to the PWM signal before the set time.

[0036] Ideally, if the amplifier gain is infinite, even a very small input voltage difference will trigger a significant change in the output voltage. However, in practical applications, due to the limited amplifier gain and the presence of non-ideal factors such as input bias voltage and noise, a certain input voltage difference is required to trigger a significant change in the output voltage. Therefore, through the voltage reduction effect of the third resistor R3 and the fourth resistor R4, when the duty cycle of the PWM signal is adjusted to change the speed of the brushless motor M, the voltage difference between the in-phase terminal and the inverting terminal of the first amplifier U1 is not sufficient to trigger the second metal-oxide semiconductor field effect transistor V2 to turn on.

[0037] When the protection circuit triggers the protection, the PWM signal is disconnected, and the duty cycle of the PWM signal directly becomes 0. At this time, there is a large voltage difference between the in-phase terminal and the inverting terminal of the first amplifier U1, and the first amplifier U1 outputs a low level, triggering the second metal-oxide semiconductor field effect transistor V2 to turn on. At this time, the brushless motor M discharges through the first crystal diode D1, the second metal-oxide semiconductor field effect transistor V2, the discharge indication unit 3, and the public ground, and discharges the energy stored in the brushless motor M in time to avoid damage to the brushless motor M and circuit components. The third resistor R3 and the fourth resistor R4 have equal resistance values, and the third crystal diode D3 and the fourth crystal diode D4 are crystal diodes of the same model, which avoids the inconsistent voltage drop during the transmission of the current voltage signal and the lagging voltage signal, resulting in incorrect voltage judgment of the first amplifier U1.

[0038] In another embodiment: the third resistor R3 and the fourth resistor R4 are replaced with two potentiometers to facilitate the adjustment of the voltage output at the in-phase terminal and the inverting terminal of the first amplifier U1. It should be noted that the resistance values ​​of the two potentiometers are equal.

[0039] In this example: See Figure 2The leakage indication unit 3 includes a second optical coupler U2, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a third transistor V3, a fourth metal-oxide semiconductor field effect transistor V4, an eighth resistor R8, a first capacitor C1, a third voice chip U3, a fifth crystal diode D5, and a sixth crystal diode D6. The first end of the second optical coupler U2 is connected to the output end of the automatic leakage control unit 2 and the output end of the indication detection unit 4. The second end of the second optical coupler U2 is grounded. The third end of the second optical coupler U2 is connected to one end of the fifth resistor R5, and the other end of the fifth resistor R5 is connected to the power supply voltage VCC. The fourth end of the second optical coupler U2 is connected to one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the base of the third transistor V3. The collector of the third transistor V3 is connected to one end of the seventh resistor R7, the other end of the seventh resistor R7 is connected to the power supply voltage VCC, the emitter of the third transistor V3 is connected to the gate of the fourth metal-oxide semiconductor field effect transistor V4, the drain of the fourth metal-oxide semiconductor field effect transistor V4 is connected to the power supply voltage VCC, the source of the fourth metal-oxide semiconductor field effect transistor V4 is connected to one end of the eighth resistor R8, the other end of the eighth resistor R8 is connected to one end of the first capacitor C1, one end of the voice chip, and the cathode of the sixth crystal diode D6, the other end of the first capacitor C1 is grounded, the other end of the voice chip is connected to the anode of the sixth crystal diode D6, the anode of the fifth crystal diode D5, and the cathode of the fifth crystal diode D5 is grounded.

[0040] After the second metal-oxide semiconductor field effect transistor V2 is turned on, the voltage is grounded through the light-emitting crystal diode inside the second optocoupler U2 to complete the discharge. In this process, the light-emitting crystal diode emits light to illuminate the photosensitive transistor inside the second optocoupler U2, and the photosensitive transistor is turned on, so that the power supply voltage VCC, the fifth resistor R5, the photosensitive transistor, and the sixth resistor R6 are turned on, and the output voltage is to the base of the third transistor V3. The base of the third transistor V3 becomes a high level, and the emitter of the third transistor V3 outputs a high level to trigger the fourth metal-oxide semiconductor field effect transistor V4 to turn on, so that the third voice chip U3 is powered and voice prompts the brushless motor M to discharge, and the fifth crystal diode D5 emits light to indicate the brushless motor M is discharging.

[0041] In another embodiment, the sixth crystal diode D6 can be omitted. The sixth crystal diode D6 is used as a voltage-stabilizing crystal diode to ensure the working voltage of the third voice chip U3 and ensure the normal operation of the third voice chip U3.

[0042] In this example: See Figure 3The leakage indication unit 3 includes a fifth crystal diode D5, the anode of the fifth crystal diode D5 is connected to the output end of the automatic leakage control unit 2 and the output end of the indication detection unit 4, and the cathode of the fifth crystal diode D5 is grounded.

[0043] The fifth crystal diode D5 is a light-emitting crystal diode, and at least one fifth crystal diode D5 can be set as the leakage indication unit 3. After the second metal-oxide semiconductor field effect transistor V2 is turned on, the brushless motor M, the first crystal diode D1, the second metal-oxide semiconductor field effect transistor V2, the fifth crystal diode D5, and the common ground form a loop for leakage, and the fifth crystal diode D5 emits light for indication.

[0044] In another embodiment: It should be noted that if the energy stored in the brushless motor M is large, the current flowing through the fifth crystal diode D5 will be too large, and the fifth crystal diode D5 may be damaged. In this case, it is not suitable to only set the fifth crystal diode D5, and a resistor can be connected in series, but this will cause the leakage rate to slow down.

[0045] In this example: See Figure 4 The leakage indication unit 3 includes a third voice chip U3, one end of the third voice chip U3 is connected to the output end of the automatic leakage control unit 2 and the output end of the indication detection unit 4, and the other end of the third voice chip U3 is grounded.

[0046] When the third voice chip U3 is working, it will give a voice prompt to the brushless motor M for current leakage. At least one third voice chip U3 can be set as the current leakage indication unit 3. After the second metal-oxide semiconductor field effect transistor V2 is turned on, the brushless motor M, the first crystal diode D1, the second metal-oxide semiconductor field effect transistor V2, the third voice chip U3 and the common ground form a loop for current leakage. The third voice chip U3 will give a voice prompt for current leakage.

[0047] In another embodiment: It should be noted that if the energy stored in the brushless motor M is small, the current flowing through the third voice chip U3 will be too small, and there is a possibility that the third voice chip U3 will not give a voice prompt. In this case, it is necessary to add an amplifier device or circuit such as a transistor to amplify the current flowing through to ensure that the third voice chip U3 works.

[0048] In this example: See Figure 2 or Figure 3 or Figure 4 The indication detection unit 4 includes a ninth resistor R9 and a first switch S1. One end of the ninth resistor R9 is connected to the power supply voltage VCC, the other end of the ninth resistor R9 is connected to one end of the first switch S1, and the other end of the first switch S1 is connected to the output end of the automatic leakage control unit 2 and the input end of the leakage indication unit 3.

[0049] If the indicating device (fifth crystal diode D5, third voice chip U3) of the leakage indicating unit 3 does not work, there is a lack of prompts, resulting in the user not knowing whether it is the leakage circuit of the brushless motor M that is faulty or the indicating device of the leakage indicating unit 3 that is faulty. At this time, the cause of the fault can be determined by manually closing the first switch S1 and observing the indicating status of the indicating device of the leakage indicating unit 3.

[0050] In another embodiment: the first switch S1 may also be a switch tube, which controls whether the switch tube is turned on by sending a voltage signal to select whether to supply power to the leakage indication unit 3 .

[0051] The working principle of the present invention is: after the motor working unit 1 receives the PWM signal, the circuit where the brushless motor M is located is turned on, and the brushless motor M is powered on and works; the automatic leakage control unit 2 is used to detect the change of the PWM signal, and when the amplitude of the reduction of the duty cycle of the PWM signal exceeds the threshold within the set time, the brushless motor M is controlled to be grounded and leaked; the leakage indication unit 3 is used to indicate the ground leakage of the brushless motor M; the indication detection unit 4 is used to control the operation of the leakage indication unit 3 through a manual switch.

[0052] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered as exemplary and non-restrictive in all respects.

[0053] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A brushless motor controller, characterized in that: The brushless motor controller includes: The motor working unit is used to connect the circuit of the brushless motor after receiving the PWM signal, so that the brushless motor is powered on and works; Automatic leakage control unit, used to detect the change of PWM signal, and control the brushless motor to ground leakage when the amplitude of the duty cycle reduction of PWM signal exceeds the threshold within the set time; A leakage current indicating unit, used to indicate the ground leakage current of the brushless motor; An indication detection unit, used to control the operation of the leakage indication unit through a manual switch; The output end of the motor working unit is connected to the input end of the automatic leakage control unit, and the output end of the automatic leakage control unit is connected to the input end of the leakage indication unit and the output end of the indication detection unit; The automatic leakage control unit includes a second crystal diode, a second capacitor, a second resistor, a third crystal diode, a fourth crystal diode, a third resistor, a fourth resistor, a third capacitor, a first amplifier, a second metal-oxide semiconductor field effect transistor, and a first crystal diode. The positive electrode of the second crystal diode introduces a PWM signal, the negative electrode of the second crystal diode is connected to one end of the second capacitor, one end of the second resistor, the positive electrode of the third crystal diode, and the positive electrode of the fourth crystal diode. The other end of the second capacitor is grounded, the other end of the second resistor is grounded, the negative electrode of the third crystal diode is connected to one end of the third resistor, the other end of the third resistor is connected to one end of the third capacitor, the first amplifier, and the negative electrode of the third crystal diode is connected to one end of the third resistor. The inverting end of the amplifier, the other end of the third capacitor is grounded, the cathode of the fourth crystal diode is connected to one end of the fourth resistor, the other end of the fourth resistor is connected to the non-inverting end of the first amplifier, the output end of the first amplifier is connected to the gate of the second metal-oxide semiconductor field effect transistor, the source of the second metal-oxide semiconductor field effect transistor is connected to the cathode of the first crystal diode, the anode of the first crystal diode is connected to the output end of the motor working unit, the drain of the second metal-oxide semiconductor field effect transistor is connected to the input end of the leakage indication unit and the output end of the indication detection unit, the third resistor and the fourth resistor have equal resistance values, and the third crystal diode and the fourth crystal diode are crystal diodes of the same model.

2. The brushless motor controller according to claim 1, characterized in that: The motor working unit includes a first resistor, a first metal-oxide semiconductor field effect transistor, and a brushless motor. One end of the first resistor is connected to the power supply voltage, the other end of the first resistor is connected to the drain of the first metal-oxide semiconductor field effect transistor, the source of the first metal-oxide semiconductor field effect transistor is connected to the input end of the automatic current discharge control unit and one end of the brushless motor, the other end of the brushless motor is grounded, and the gate of the first metal-oxide semiconductor field effect transistor introduces a PWM signal.

3. The brushless motor controller according to claim 1, characterized in that: The leakage indication unit includes a second optical coupler, a fifth resistor, a sixth resistor, a seventh resistor, a third transistor, a fourth metal-oxide semiconductor field effect transistor, an eighth resistor, a first capacitor, a third voice chip, a fifth crystal diode, and a sixth crystal diode. The first end of the second optical coupler is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit. The second end of the second optical coupler is grounded. The third end of the second optical coupler is connected to one end of the fifth resistor. The other end of the fifth resistor is connected to the power supply voltage. The fourth end of the second optical coupler is connected to one end of the sixth resistor. The other end of the sixth resistor is connected to the base of the third transistor. The collector is connected to one end of the seventh resistor, the other end of the seventh resistor is connected to the power supply voltage, the emitter of the third transistor is connected to the gate of the fourth metal-oxide semiconductor field effect transistor, the drain of the fourth metal-oxide semiconductor field effect transistor is connected to the power supply voltage, the source of the fourth metal-oxide semiconductor field effect transistor is connected to one end of the eighth resistor, the other end of the eighth resistor is connected to one end of the first capacitor, one end of the voice chip, and the cathode of the sixth crystal diode, the other end of the first capacitor is grounded, the other end of the voice chip is connected to the anode of the sixth crystal diode and the anode of the fifth crystal diode, and the cathode of the fifth crystal diode is grounded.

4. The brushless motor controller according to claim 1, characterized in that: The leakage indication unit comprises a fifth crystal diode, the anode of the fifth crystal diode is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit, and the cathode of the fifth crystal diode is grounded.

5. The brushless motor controller according to claim 1, characterized in that: The leakage indication unit comprises a third voice chip, one end of the third voice chip is connected to the output end of the automatic leakage control unit and the output end of the indication detection unit, and the other end of the third voice chip is grounded.

6. The brushless motor controller according to any one of claims 1 to 5, characterized in that: The indication detection unit includes a ninth resistor and a first switch, one end of the ninth resistor is connected to the power supply voltage, the other end of the ninth resistor is connected to one end of the first switch, and the other end of the first switch is connected to the output end of the automatic leakage control unit and the input end of the leakage indication unit.

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