WO2021068241A1 - Brushless direct current motor hall sensor fault-tolerant control device and control method therefor - Google Patents

Abstract

The present invention relates to a brushless direct current motor Hall sensor fault-tolerant control device and a control method therefor, comprising a Hall sensor unit, a brushless direct current motor three-phase stator winding, an inverter and a controller; the Hall sensor unit is connected with the controller and is used for detecting a rotor position of a brushless direct current motor; the inverter is connected with the brushless direct current motor three-phase stator winding and is used for injecting a voltage signal into the brushless direct current motor three-phase stator winding so as to realize driving of the brushless direct-current motor; the controller is connected with the inverter and is used for processing an output signal of the Hall sensor unit and outputting a driving signal to the inverter. The present invention has advantages that through improvement of a traditional Hall sensor acquisition circuit, complete acquisition of edge signals and high and low levels of the Hall sensor is achieved, fault-tolerant control is achieved on the basis of an improved electrical angle calculation method, and the control method is efficient in terms of algorithms and easy to achieve.

Description

Brushless DC motor Hall sensor fault-tolerant control device and control method thereof Technical field

The invention belongs to the field of brushless DC motor control, and in particular relates to a fault-tolerant control device for a Hall sensor of a brushless DC motor and a control method thereof.

Background technique

Brushless DC motors have the advantages of high efficiency, fast response, and high power density. Therefore, brushless DC motors have been widely used in more and more industries. Vector control, also known as sine wave drive control, has higher efficiency, less noise and higher control flexibility than square wave drive control.

In some low-cost controller fields, Hall sensors are used as position sensors to realize the estimation of electrical angles in vector control. Rather, the Hall sensor as a Hall position sensor as a semiconductor element, because of its own characteristics, it is difficult to ensure its long-term and reliable operation in harsh working situations such as high and low temperature, strong impact, and strong vibration. Once the Hall position sensor fails, it will cause serious distortions to the three-phase current of the brushless DC motor. In response to this problem, the existing relatively stable fault-tolerant method is to first diagnose which Hall sensor is faulty, and then rely on the other two Hall sensors to reconstruct the other Hall sensor. However, the fault diagnosis process takes a long time, and some need to stop outputting control signals to the inverter, which affects the control efficiency. Moreover, using two Hall sensors to reconstruct another Hall sensor algorithm is complicated to implement, and is not suitable for application in low-end controllers.

The present invention improves the Hall sensor detection circuit and the electrical angle estimation method, and the fault-tolerant control simplifies the fault diagnosis process and does not rely on signal reconstruction, and the control efficiency is high and easy to implement.

Summary of the invention

The technical problem to be solved by the present invention is to provide a brushless DC motor Hall sensor fault-tolerant control device and a control method thereof, so as to solve the problems of low efficiency and high implementation difficulty of the traditional fault-tolerant control method.

In order to solve the above technical problems, the technical scheme of the present invention is: a brushless DC motor Hall sensor fault-tolerant control device, its innovation lies in: including a Hall sensor unit, a brushless DC motor three-phase stator winding, an inverter and Controller,

The Hall sensor unit is connected to the controller and is used to detect the rotor position of the brushless DC motor; the inverter is connected to the three-phase stator winding of the brushless DC motor and is used to transfer the brushless DC motor to the three-phase stator winding. The three-phase stator windings of the motor inject voltage signals to drive the brushless DC motor; the controller is connected to the inverter and is used to process the output signal of the Hall sensor unit and output the drive to the inverter signal.

Further, the hall sensor unit includes a hall sensor A, a hall sensor B, and a hall sensor C; the controller includes a first group of pins and a second group of pins, and the first group of pins and the first group of pins Both sets of pins are connected to the Hall sensor unit;

Wherein, the function of the first group of pins is set as an external interrupt capture function, which is used to capture the rising and falling edges of the level signals of the Hall sensor A, Hall sensor B, and Hall sensor C; The function of the second group of pins is set as a PWM input capture function, which is used to obtain the high level time and the low level time of the level signals of the Hall sensor A, the Hall sensor B, and the Hall sensor C.

A control method of the above-mentioned brushless DC motor Hall sensor fault-tolerant control device, its innovation is that: the control method includes the following steps:

Step 1: When the rising or falling edge information of the Hall sensor is captured, the brushless DC motor running timing time is cleared, the electrical angle of the brushless DC motor is corrected, and then the high level time or low voltage of the Hall sensor is obtained Peace time

Step 2: According to the sequence of capturing the rising or falling edge of the Hall sensor, judge whether the Hall sensor is faulty; when a fault occurs, calculate the electrical angle with the high level time and low level time of other normal Hall sensors; When no fault occurs, calculate the electrical angle with the high level time and low level time of the three Hall sensors;

Step 3: Calculate the electrical angle based on the electrical angle corrected in step 1, the running timing time of the brushless DC motor and the high level time or low level time of the normal Hall sensor.

Further, the relationship between the acquisition of the high-level time or the low-level time of the Hall sensor in step 1 and the rising edge or the falling edge of the Hall sensor is specifically:

When the rising edge of Hall sensor A is captured, the low level time of Hall sensor A is obtained. When the falling edge of Hall sensor A is captured, the high level time of Hall sensor A is obtained. When the Hall sensor A is captured Obtain the low level time of Hall sensor B at the rising edge of B, obtain the high level time of Hall sensor B when the falling edge of Hall sensor B is captured, and obtain the high level time of Hall sensor B when the rising edge of Hall sensor C is captured The low level time of the Hall sensor C, when the falling edge of the Hall sensor C is captured, the high level time of the Hall sensor C is obtained.

Further, according to the sequence of capturing the rising edge or the falling edge of the Hall sensor in step 2, the specific method for judging the failure of the Hall sensor is as follows:

When the brushless DC motor rotates counterclockwise, when the rising edge of Hall sensor C is captured and the last captured is the rising edge of Hall sensor B, or when the falling edge of Hall sensor C is captured and the last captured When it is the falling edge of Hall sensor B, it is judged that Hall sensor A is faulty; when the rising edge of Hall sensor A is captured and the last time is captured as the rising edge of Hall sensor C, or when Hall sensor A is captured When the rising edge of Hall sensor B is captured and the last time is captured as the falling edge of Hall sensor C, it is judged that Hall sensor B is faulty; when the rising edge of Hall sensor B is captured and the last time is captured as the rising edge of Hall sensor A, or, When the falling edge of Hall sensor B is captured and the last time is captured as the falling edge of Hall sensor A, it is judged that Hall sensor C is faulty;

When the brushless DC motor rotates clockwise, when the rising edge of Hall sensor B is captured and the last captured is the rising edge of Hall sensor C, or when the falling edge of Hall sensor B is captured and the last captured When it is the falling edge of Hall sensor C, it is judged that Hall sensor A is faulty; when the rising edge of Hall sensor C is captured and the last time is captured as the rising edge of Hall sensor A, or when Hall sensor C is captured When the rising edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor A, it is judged that Hall sensor B is faulty; when the rising edge of Hall sensor A is captured and the last time is captured as the rising edge of Hall sensor B, or, When the falling edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor B, it is judged that Hall sensor C is faulty.

Further, in step 3, according to the electrical angle corrected in step 1, the operation timing time of the brushless DC motor and the high-level time or low-level time of the normal Hall sensor are used to calculate the electrical angle of the brushless DC motor. The specific method as follows:

Among them, “θ _r ”is the electrical angle of the brushless DC motor, “T _j ” is the high level time or low level time of the normal Hall sensor, “E _i ”is the corrected electrical angle, and “t ₀ ” is Brushless DC motor running timing time.

Further, the electrical angle correction method in step 1 and the _{value of "E i} "are specifically:

When the brushless DC motor rotates counterclockwise, the electrical angle is corrected to E ₁ =240 when the rising edge of Hall sensor A is captured, and the electrical angle is corrected to E ₂ =300 when the falling edge of Hall sensor C is captured; When the rising edge of Hall sensor B is captured, the electrical angle is corrected to E ₃ =0; when the falling edge of Hall sensor A is captured, the electrical angle is corrected to E ₄ ＝60; when the rising edge of Hall sensor C is captured When the electrical angle is corrected to E ₅ ＝120; when the falling edge of Hall sensor B is captured, the electrical angle is corrected to E ₆ ＝180;

When the brushless DC motor rotates clockwise, the electrical angle is corrected to E ₁ =60 when the rising edge of Hall sensor A is captured, and the electrical angle is corrected to E ₂ =120 when the falling edge of Hall sensor C is captured; When the rising edge of Hall sensor B is captured, the electrical angle is corrected to E ₃ ＝180; when the falling edge of Hall sensor A is captured, the electrical angle is corrected to E ₄ ＝240; when the rising edge of Hall sensor C is captured When the electrical angle is corrected to E ₅ =300; when the falling edge of the Hall sensor B is captured, the electrical angle is corrected to E ₆ =0.

Further, the high-level time or low-level time T _j of the normal Hall sensor, T ₁ to T ₆ are specifically expressed as: T ₁ is the low-level time of the Hall sensor A, and T ₂ is the Hall sensor A. The high level time _{of Hall sensor C, T 3} is the low level time of Hall sensor B, T ₄ is the high level time of Hall sensor A, T ₅ is the low level time of Hall sensor C, T ₆ It is the high level time of Hall sensor B.

Further, the calculation method of the electrical angle is specifically:

When the fault has been determined A Hall sensor with a Hall sensor C is high time T _2, the Hall sensor B is low time T _3, the low time T ₅ C Hall sensor and a Hall sensor B's high level time T ₆ calculates the electrical angle;

When the fault has been judged B Hall sensor, with a Hall sensor A high time T _1, the Hall sensor C high time T _2, A high time T ₄ of the Hall sensor and Hall sensor The low level time T _{5 of} C calculates the electrical angle;

When it is judged that Hall sensor C is faulty, the high level time T ₁ of Hall sensor A, the low level time T ₃ of Hall sensor B, the high level time T _{4 of} Hall sensor A, and the high level time of Hall sensor B The high level time T ₆ calculates the electrical angle.

Further, the calculation method of the electrical angle is specifically as follows: each time the rising or falling edge of the Hall sensor is captured, the brushless DC motor is set to operate for a time t ₀ =0, and the electrical angle θ _{r is} directly equal to the corrected Electrical angle E _i .

Further, a timer is started before step 1 to obtain the running timing t _{0 of the} brushless DC motor.

The advantages of the present invention are:

(1) The present invention realizes the complete collection of the rising edge, falling edge, high level time, and low level time of the three Hall sensors by improving the Hall sensor acquisition circuit, which provides convenience for the estimation of electrical angles. It is more accurate than the traditional Hall sensor detection method;

(2) The present invention analyzes the order of appearance of the Hall sensor, and according to the edge information of the Hall sensor currently captured and the edge information of the Hall sensor captured last time, the fault type of the Hall sensor can be judged. Method suggestions, easy to implement;

(3) The present invention provides an electrical angle estimation method that utilizes the running time of the brushless DC motor, the correction of the electrical angle, and the high-level time or the low-level time of the Hall sensor. It is not only suitable for electrical angle estimation under normal conditions, but also Electric angle estimation under Hall sensor failure, the calculation method is simple and suitable for low-performance controllers.

Description of the drawings

The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

Fig. 1 is a schematic diagram of a fault-tolerant control device for a Hall sensor of a brushless DC motor implemented in the present invention.

Fig. 2 is a flowchart of a fault-tolerant control method for a Hall sensor of a brushless DC motor implemented in the present invention.

Fig. 3 is a schematic diagram of the level signals of Hall sensors A, B, and C according to a specific implementation of the present invention.

FIG. 4 is a schematic diagram of the reverse/clockwise edge signal sequence when the Hall sensor A is faulty according to the specific implementation of the present invention.

Fig. 5 is a schematic diagram of fault-tolerant control when the Hall sensor A fails in a specific implementation of the present invention.

Detailed ways

The following embodiments can enable those skilled in the art to understand the present invention more comprehensively, but they do not limit the present invention to the scope of the described embodiments.

Example

As shown in Figure 1, this embodiment provides a Hall sensor fault-tolerant control device for a brushless DC motor, which includes a Hall sensor unit, a brushless DC motor three-phase stator winding, an inverter, and a controller; the Hall sensor unit It is connected to the controller to detect the rotor position of the brushless DC motor; the inverter is connected to the three-phase stator winding of the brushless DC motor and is used to inject voltage signals into the three-phase stator winding of the brushless DC motor to realize the brushless DC motor The controller is connected with the inverter, and is used to process the output signal of the Hall sensor unit and output the driving signal to the inverter.

Optionally, the Hall sensor unit includes Hall sensor A, Hall sensor B, and Hall sensor C; the controller includes a first set of pins IO-1 and a second set of pins IO-2, and the first set of leads The pin IO-1 and the second group of pins IO-2 are both connected to the Hall sensor unit.

Among them, the three-phase stator windings of the brushless DC motor include U-phase windings, V-phase windings, and W-phase windings; the inverter includes power switching devices T1 to T6.

Optionally, the function of the first group of pins IO-1 is set as an external interrupt capture function, which is used to capture the rising and falling edges of the level signals of Hall sensor A, Hall sensor B, and Hall sensor C; The function of the second group of pins IO-2 is set as the PWM input capture function, which is used to obtain the high level time and low level time of the level signals of Hall sensor A, Hall sensor B, and Hall sensor C.

If only one set of controller pins are used and set as the external interrupt capture function, then only the rising and falling edges of the Hall sensor can be obtained, and additional timers need to be called to measure the high level time and low voltage of the Hall sensor Normal time, this method occupies a lot of resources, and the measurement level time accuracy is low. Or, if only a set of controller pins are used and set to the PWM input capture function, the rising and falling edges of the Hall sensor cannot be distinguished, which affects the electrical angle correction. Therefore, selecting two sets of controller pins to process the Hall sensor at the same time helps to extract the information from the Hall sensor and improve the accuracy of electrical angle calculation.

As shown in FIG. 2, this embodiment provides a fault-tolerant control method for a Hall sensor of a brushless DC motor, which includes the following steps:

Step S1: When the rising or falling edge information of the Hall sensor is captured, the brushless DC motor running timing time is cleared, the electrical angle of the brushless DC motor is corrected, and then the high level time or low voltage of the Hall sensor is obtained. Peace time

Step S2: Determine whether the Hall sensor is faulty according to the sequence of capturing the rising or falling edge of the Hall sensor; when a fault occurs, calculate the electrical angle based on the high level time and low level time of other normal Hall sensors; When no fault occurs, calculate the electrical angle with the high level time and low level time of the three Hall sensors;

Step S3: Calculate the electrical angle according to the electrical angle corrected in step S1, the running timing time of the brushless DC motor and the high level time or low level time of the normal Hall sensor. As shown in Figure 3, it is a schematic diagram of the level signals of Hall sensors A, B, and C.

In step S1, the high-level time or low-level time of the Hall sensor is acquired, and the relationship with the rising or falling edge of the Hall sensor is specifically:

When the rising edge of Hall sensor A is captured, the low level time T1 of Hall sensor A is acquired. When the falling edge of Hall sensor A is captured, the high level time T4 of Hall sensor A is acquired. When the falling edge of Hall sensor A is captured, the high level time T4 of Hall sensor A is acquired. Obtain the low level time T3 of Hall sensor B at the rising edge of Hall sensor B, obtain the high level time T6 of Hall sensor B when the falling edge of Hall sensor B is captured, and obtain the high level time T6 of Hall sensor B when the falling edge of Hall sensor B is captured. The low level time T5 of the Hall sensor C is acquired at the rising edge, and the high level time T2 of the Hall sensor C is acquired when the falling edge of the Hall sensor C is captured.

Optionally, in step S2, according to the sequence of capturing the rising or falling edge of the Hall sensor, the specific method for judging the failure of the Hall sensor is as follows: when the brushless DC motor rotates counterclockwise, when the rising edge of the Hall sensor C is captured And when the last capture is the rising edge of Hall sensor B, or when the falling edge of Hall sensor C is captured and the last capture is the falling edge of Hall sensor B, it is judged that Hall sensor A is faulty; When the rising edge of Hall sensor A and the last time captured as the rising edge of Hall sensor C, or when the falling edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor C, judge Hall Sensor B failure; when the rising edge of Hall sensor B is captured and the last time is captured as the rising edge of Hall sensor A, or when the falling edge of Hall sensor B is captured and the last time is captured as Hall sensor A At the falling edge, it is judged that the Hall sensor C is faulty.

When the brushless DC motor rotates clockwise, when the rising edge of Hall sensor B is captured and the last captured is the rising edge of Hall sensor C, or when the falling edge of Hall sensor B is captured and the last captured When it is the falling edge of Hall sensor C, it is judged that Hall sensor A is faulty; when the rising edge of Hall sensor C is captured and the last time is the rising edge of Hall sensor A, or when Hall sensor C is captured When the rising edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor A, it is judged that Hall sensor B is faulty; when the rising edge of Hall sensor A is captured and the last time is captured as the rising edge of Hall sensor B, or, When the falling edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor B, it is judged that Hall sensor C is faulty.

As shown in Figure 4, it is a schematic diagram of the reverse/clockwise edge signal sequence when Hall sensor A fails. When the brushless DC motor rotates counterclockwise, when the rising edge X3 of Hall sensor C is captured and the last time is captured as the rising edge X1 of Hall sensor B, or when the falling edge X4 of Hall sensor C is captured and goes up When the first capture is the falling edge X2 of Hall sensor B, it is judged that Hall sensor A is faulty; because when the Hall sensor is normal, when the rising edge X3 of Hall sensor C is captured, the edge signal captured last time should be The falling edge of Hall sensor A, or when the falling edge X4 of Hall sensor C is captured, the last captured edge signal should be the rising edge of Hall sensor A.

When the brushless DC motor rotates clockwise, when the rising edge X2 of Hall sensor B is captured and the last time is captured as the rising edge X4 of Hall sensor C, or when the falling edge X1 of Hall sensor B is captured and goes up When one capture is the falling edge X3 of Hall sensor C, it is judged that Hall sensor A is faulty. Because when the Hall sensor is normal, when the rising edge X2 of Hall sensor B is captured, the last captured edge signal should be the falling edge of Hall sensor A, or when the falling edge X1 of Hall sensor B is captured When, the edge signal captured last time should be the rising edge of Hall sensor A.

Optionally, in step 3, the electrical angle of the brushless DC motor is calculated according to the electrical angle corrected in step S1, the running timing time of the brushless DC motor and the high level time or low level time of the normal Hall sensor. The specific method is as follows : Among them, "θr" is the electrical angle of the brushless DC motor, "Tj" is the high level time or low level time of the normal Hall sensor, "Ei" is the corrected electrical angle, and "t0" is the brushless DC motor. Motor running timing time. The formula shows that on the basis of the corrected electrical angle "Ei", the integral of the average electrical angular velocity 180/Tj is added to obtain the calculated electrical angle.

Optionally, the electrical angle correction method and the value of "Ei" in step S1 are specifically as follows: When the brushless DC motor rotates counterclockwise, when the rising edge of Hall sensor A is captured, the electrical angle is corrected to E1=240, When the falling edge of Hall sensor C is captured, the electrical angle is corrected to E2=300; when the rising edge of Hall sensor B is captured, the electrical angle is corrected to E3=0; when the falling edge of Hall sensor A is captured, the electrical angle is corrected to E2=300. The angle is corrected to E4=60; when the rising edge of Hall sensor C is captured, the electrical angle is corrected to E5=120; when the falling edge of Hall sensor B is captured, the electrical angle is corrected to E6=180; when the brushless DC motor When rotating clockwise, when the rising edge of Hall sensor A is captured, the electrical angle is corrected to E1=60, when the falling edge of Hall sensor C is captured, the electrical angle is corrected to E2=120; when Hall sensor B is captured The electrical angle is corrected to E3=180 when the rising edge of the hall sensor A is captured; the electrical angle is corrected to E4=240 when the falling edge of the Hall sensor A is captured; the electrical angle is corrected to E5=300 when the rising edge of the Hall sensor C is captured; When the falling edge of Hall sensor B is captured, the electrical angle is corrected to E6=0.

Optionally, when Hall sensor A is judged to be faulty, use the high level time T2 of Hall sensor C, the low level time T3 of Hall sensor B, the low level time T5 of Hall sensor C, and the Hall sensor C. The high level time T6 of sensor B calculates the electrical angle; when it is judged that Hall sensor B is faulty, use the high level time T1 of Hall sensor A, the high level time T2 of Hall sensor C, and the high level time T2 of Hall sensor A. The high level time T4 and the low level time T5 of Hall sensor C calculate the electrical angle; when it is judged that Hall sensor C is faulty, the high level time of Hall sensor A is T1, and the low level time of Hall sensor B is T3. , The high level time T4 of Hall sensor A and the high level time T6 of Hall sensor B calculate the electrical angle.

Optionally, each time the rising edge or the falling edge of the Hall sensor is captured, the brushless DC motor is set to operate for a timing time t0=0, and the electrical angle θr is directly equal to the corrected electrical angle Ei.

Optionally, a timer is started before step S1 to obtain the running time t0 of the brushless DC motor.

As shown in Figure 5, it is a schematic diagram of fault-tolerant control when Hall sensor A fails. When the rising edge X3 of the Hall sensor C is captured, set the brushless DC motor to run the timing time t0=0, correct the electrical angle to θr=E5=120°, and then obtain the low level time T5 of the Hall sensor C; Between the rising edge X3 of Hall sensor C and the falling edge X2 of Hall sensor B, the electrical angle is calculated according to the low level time T5 of Hall sensor C and the correction angle E5, specifically: When the Hall sensor is captured At the falling edge X2 of B, set the brushless DC motor to run the timing time t0=0, correct the electrical angle to θr=E6=180°, and then obtain the high level time T6 of Hall sensor B; Between the falling edge X2 and the rising edge X4 of the Hall sensor C, the electrical angle is calculated according to the low and high level time T6 of the Hall sensor B and the correction angle E6. The specifics are: the same can be obtained, when the Hall sensor is obtained When the falling edge X4 of C or the rising edge X1 of Hall sensor B is obtained, the high level time or low level time Tj of the corresponding normal Hall sensor and the corrected electrical angle Ei are selected to calculate the electrical angle.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have Various changes and improvements fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims (11)

1. A fault-tolerant control device for a Hall sensor of a brushless DC motor, which is characterized in that it comprises a Hall sensor unit, a three-phase stator winding of a brushless DC motor, an inverter and a controller.

   The Hall sensor unit is connected to the controller and is used to detect the rotor position of the brushless DC motor; the inverter is connected to the three-phase stator winding of the brushless DC motor and is used to transfer the brushless DC motor to the three-phase stator winding. The three-phase stator windings of the motor inject voltage signals to drive the brushless DC motor; the controller is connected to the inverter and is used to process the output signal of the Hall sensor unit and output the drive to the inverter signal.
2. The brushless DC motor Hall sensor fault-tolerant control device according to claim 1, wherein the Hall sensor unit includes Hall sensor A, Hall sensor B, and Hall sensor C; and the controller includes a One set of pins and a second set of pins, and both the first set of pins and the second set of pins are connected to the Hall sensor unit;

   Wherein, the function of the first group of pins is set as an external interrupt capture function, which is used to capture the rising and falling edges of the level signals of the Hall sensor A, Hall sensor B, and Hall sensor C; The function of the second group of pins is set as a PWM input capture function, which is used to obtain the high level time and the low level time of the level signals of the Hall sensor A, the Hall sensor B, and the Hall sensor C.
3. A control method of a fault-tolerant control device for a Hall sensor of a brushless DC motor according to claim 1, wherein the control method comprises the following steps:

   Step 1: When the rising or falling edge information of the Hall sensor is captured, the brushless DC motor running timing time is cleared, the electrical angle of the brushless DC motor is corrected, and then the high level time or low voltage of the Hall sensor is obtained Peace time

   Step 2: According to the sequence of capturing the rising or falling edge of the Hall sensor, judge whether the Hall sensor is faulty; when a fault occurs, calculate the electrical angle with the high level time and low level time of other normal Hall sensors; When no fault occurs, calculate the electrical angle with the high level time and low level time of the three Hall sensors;

   Step 3: Calculate the electrical angle based on the electrical angle corrected in step 1, the running timing time of the brushless DC motor and the high level time or low level time of the normal Hall sensor.
4. The control method of the Hall sensor fault-tolerant control device of the brushless DC motor according to claim 3, wherein the acquisition of the high level time or the low level time of the Hall sensor in step 1 is related to the rise of the Hall sensor. The relationship between the edge or the falling edge is specifically:

   When the rising edge of Hall sensor A is captured, the low level time of Hall sensor A is obtained. When the falling edge of Hall sensor A is captured, the high level time of Hall sensor A is obtained. When the Hall sensor A is captured Obtain the low level time of Hall sensor B at the rising edge of B, obtain the high level time of Hall sensor B when the falling edge of Hall sensor B is captured, and obtain the high level time of Hall sensor B when the rising edge of Hall sensor C is captured The low level time of the Hall sensor C, when the falling edge of the Hall sensor C is captured, the high level time of the Hall sensor C is obtained.
5. The control method of the brushless DC motor Hall sensor fault-tolerant control device according to claim 3, characterized in that: in step 2, according to the sequence of capturing the rising edge or the falling edge of the Hall sensor, determine the specific fault of the Hall sensor Methods as below:

   When the brushless DC motor rotates counterclockwise, when the rising edge of Hall sensor C is captured and the last captured is the rising edge of Hall sensor B, or when the falling edge of Hall sensor C is captured and the last captured When it is the falling edge of Hall sensor B, it is judged that Hall sensor A is faulty; when the rising edge of Hall sensor A is captured and the last time is captured as the rising edge of Hall sensor C, or when Hall sensor A is captured When the rising edge of Hall sensor B is captured and the last time is captured as the falling edge of Hall sensor C, it is judged that Hall sensor B is faulty; when the rising edge of Hall sensor B is captured and the last time is captured as the rising edge of Hall sensor A, or, When the falling edge of Hall sensor B is captured and the last time is captured as the falling edge of Hall sensor A, it is judged that Hall sensor C is faulty;

   When the brushless DC motor rotates clockwise, when the rising edge of Hall sensor B is captured and the last captured is the rising edge of Hall sensor C, or when the falling edge of Hall sensor B is captured and the last captured When it is the falling edge of Hall sensor C, it is judged that Hall sensor A is faulty; when the rising edge of Hall sensor C is captured and the last time is captured as the rising edge of Hall sensor A, or when Hall sensor C is captured When the rising edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor A, it is judged that Hall sensor B is faulty; when the rising edge of Hall sensor A is captured and the last time is captured as the rising edge of Hall sensor B, or, When the falling edge of Hall sensor A is captured and the last time is captured as the falling edge of Hall sensor B, it is judged that Hall sensor C is faulty.
6. The control method of the fault-tolerant control device for the Hall sensor of the brushless DC motor according to claim 3, characterized in that: in step 3, according to the electrical angle corrected in step 1, the running timing of the brushless DC motor is the same as that of the normal Hall sensor. The high-level time or low-level time of the sensor calculates the electrical angle of the brushless DC motor. The specific method is as follows:

   

   

   Among them, “θ _r ”is the electrical angle of the brushless DC motor, “T _j ” is the high level time or low level time of the normal Hall sensor, “E _i ”is the corrected electrical angle, and “t ₀ ” is Brushless DC motor running timing time.
7. The control method of the brushless DC motor Hall sensor fault-tolerant control device according to claim 3 or 6, characterized in that: the electrical angle correction method in step 1 and the _{value of "E i} "are specifically:

   When the brushless DC motor rotates counterclockwise, the electrical angle is corrected to E ₁ =240 when the rising edge of Hall sensor A is captured, and the electrical angle is corrected to E ₂ =300 when the falling edge of Hall sensor C is captured; When the rising edge of Hall sensor B is captured, the electrical angle is corrected to E ₃ =0; when the falling edge of Hall sensor A is captured, the electrical angle is corrected to E ₄ ＝60; when the rising edge of Hall sensor C is captured When the electrical angle is corrected to E ₅ ＝120; when the falling edge of Hall sensor B is captured, the electrical angle is corrected to E ₆ ＝180;

   When the brushless DC motor rotates clockwise, the electrical angle is corrected to E ₁ =60 when the rising edge of Hall sensor A is captured, and the electrical angle is corrected to E ₂ =120 when the falling edge of Hall sensor C is captured; When the rising edge of Hall sensor B is captured, the electrical angle is corrected to E ₃ ＝180; when the falling edge of Hall sensor A is captured, the electrical angle is corrected to E ₄ ＝240; when the rising edge of Hall sensor C is captured When the electrical angle is corrected to E ₅ =300; when the falling edge of the Hall sensor B is captured, the electrical angle is corrected to E ₆ =0.
8. The control method of the brushless DC motor Hall sensor fault-tolerant control device according to claim 6, characterized in that: the high level time or the low level time T _j , T ₁ ～T _{6 of the normal Hall sensor} Specifically expressed as: T ₁ is the low level time of Hall sensor A, T ₂ is the high level time of Hall sensor C, T ₃ is the low level time of Hall sensor B, and T ₄ is the Hall sensor a high level of time, T ₅ is the low time of the Hall sensor C, T ₆ is a high-level period B of the Hall sensor.
9. The control method of a fault-tolerant control device for a Hall sensor of a brushless DC motor according to claim 6, wherein the calculation method of the electrical angle is specifically:

   When the fault has been determined A Hall sensor with a Hall sensor C is high time T _2, the Hall sensor B is low time T _3, the low time T ₅ C Hall sensor and a Hall sensor B's high level time T ₆ calculates the electrical angle;

   When the fault has been judged B Hall sensor, with a Hall sensor A high time T _1, the Hall sensor C high time T _2, A high time T ₄ of the Hall sensor and Hall sensor The low level time T _{5 of} C calculates the electrical angle;

   When it is judged that Hall sensor C is faulty, the high level time T ₁ of Hall sensor A, the low level time T ₃ of Hall sensor B, the high level time T _{4 of} Hall sensor A, and the high level time of Hall sensor B The high level time T ₆ calculates the electrical angle.
10. The control method of the brushless DC motor Hall sensor fault-tolerant control device according to claim 6, characterized in that: the calculation method of the electrical angle is specifically: every time the rising edge or the falling edge of the Hall sensor is captured , Let the brushless DC motor run timing time t ₀ =0, and the electrical angle θ _{r is} directly equal to the corrected electrical angle E _i .
11. The control method of a fault-tolerant control device for a Hall sensor of a brushless DC motor according to claim 3, wherein the timer is started before step 1 to obtain the running timing t _{0 of the} brushless DC motor.

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