Motor position signal fault judgment method, device, system and vehicle

Abstract

The present application discloses a method, device, system and vehicle for judging the position signal fault of a motor. The method for judging the position signal fault of a motor provided in the embodiment of the present application includes: obtaining an electrical signal output by a position sensor, the position sensor is used to obtain the angle of the motor; based on the electrical signal, using a first algorithm to calculate to obtain the first angle of the motor; based on the electrical signal, using a second algorithm to calculate to obtain the second angle of the motor; when the difference between the first angle and the second angle is less than or equal to a preset value, judging that the position signal of the motor is fault-free. In this way, the position sensor signal is diagnosed based on the mathematical characteristics of the electrical signal output by the position sensor itself, and the safety verification of the position sensor is achieved at a relatively low cost, so as to avoid the vehicle from generating unexpected torque during the power output process and ensure the normal driving of the vehicle. No hardware redundancy is required, which reduces the development cost of functional safety monitoring of the position sensor and improves the robustness of the system.

Description

Technical Field

[0001] The present application relates to the field of electric motors, and in particular to a method, device, system and vehicle for determining position signal faults of electric motors. Background Art

[0002] For hybrid and pure electric vehicles, the error of the motor position signal will lead to deviation in the motor torque estimation, resulting in unexpected torque generation and even traffic accidents. Therefore, it is necessary to design a dedicated monitoring solution to detect the validity of the motor position signal. In related technologies, multiple speed sensor signals are usually used for mutual verification. These solutions occupy a lot of hardware resources, are complex to control and have high costs. Summary of the invention

[0003] Embodiments of the present application provide a method, device, system and vehicle for determining a position signal fault of a motor.

[0004] The method for determining a motor position signal fault provided by the embodiment of the present application includes:

[0005] Acquire an electrical signal output by a position sensor, wherein the position sensor is used to acquire the angle of the motor;

[0006] Based on the electrical signal, using a first algorithm to calculate to obtain a first angle of the motor;

[0007] Based on the electrical signal, using a second algorithm to calculate to obtain a second angle of the motor;

[0008] When the difference between the first angle and the second angle is less than or equal to a preset value, it is determined that the position signal of the motor has no fault.

[0009] In this way, the position sensor signal is diagnosed based on the mathematical characteristics of the electrical signal output by the position sensor, and the safety verification of the position sensor is achieved at a low cost, avoiding the vehicle from generating unexpected torque during the power output process and ensuring the normal driving of the vehicle. Without the need for hardware redundancy, self-diagnosis can be performed through the mathematical characteristics of the position sensor signal itself, realizing self-verification of whether the electrical signal is valid, reducing the development cost of the position sensor function safety monitoring, and improving the robustness of the control system.

[0010] In some embodiments, the calculating based on the electrical signal using a first algorithm to obtain a first angle of the motor includes:

[0011] Based on the electrical signal, a tangent value of a first angle of the motor is calculated using a first algorithm;

[0012] The first angle of the motor is obtained according to a tangent value of the first angle of the motor.

[0013] In some embodiments, the first algorithm is:

[0014] Among them, θ n-1 is the angle of the motor at time n-1.

[0015] In some embodiments, the calculating based on the electrical signal using a second algorithm to obtain a second angle of the motor includes:

[0016] Based on the electrical signal, a tangent value of a second angle of the motor is calculated using a second algorithm;

[0017] The second angle of the motor is obtained according to the tangent value of the second angle of the motor.

[0018] In some embodiments, the second algorithm is:

[0019] Among them, θ n is the angle of the motor at time n, θ n-1 is the angle of the motor at time n-1, θ n-2 is the angle of the motor at time n-2.

[0020] In some embodiments, the method for determining a position signal fault of a motor includes:

[0021] Within a preset time, when the difference between the first angle and the second angle is greater than the preset value, it is determined that the position signal of the motor is faulty.

[0022] In some embodiments, before calculating based on the electrical signal using a first algorithm to obtain the first angle of the motor, the method for determining a position signal fault of the motor further includes:

[0023] The electrical signal is modified.

[0024] The control device provided in the embodiment of the present application includes:

[0025] An acquisition module, used to acquire an electrical signal output by a position sensor, wherein the position sensor is used to acquire the angle of the motor;

[0026] A first calculation module, configured to calculate a first angle of the motor based on the electrical signal using a first algorithm;

[0027] A second calculation module, configured to calculate, based on the electrical signal, using a second algorithm to obtain a second angle of the motor;

[0028] The judgment module is used to judge that the position signal of the motor has no fault when the difference between the first angle and the second angle is less than or equal to a preset value.

[0029] The control system provided in the embodiment of the present application includes a motor, a position sensor, an inverter and a controller. The position sensor is connected to the motor. The inverter is connected to the motor. The controller is connected to the position sensor and the inverter, and the controller is used to implement the motor position signal fault judgment method described in any of the above embodiments.

[0030] The vehicle provided in the embodiment of the present application includes the above-mentioned control system.

[0031] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0033] Figure 1 It is a flow chart of a method for determining a position signal fault of a motor according to an embodiment of the present application;

[0034] Figure 2 It is a structural schematic diagram of a control system according to an embodiment of the present application;

[0035] Figure 3 is a schematic diagram of a module of a control device in an embodiment of the present application;

[0036] Figure 4 It is another flow chart of the method for determining the position signal fault of a motor according to an embodiment of the present application;

[0037] Figure 5 is another flow chart of a method for determining a position signal fault of a motor according to an embodiment of the present application;

[0038] Figure 6 It is another flow chart of the method for determining the position signal fault of the motor according to the embodiment of the present application;

[0039] Figure 7 It is another flow chart of the method for determining the position signal fault of the motor according to the embodiment of the present application;

[0040] Figure 8 It is another flow chart of the method for determining the position signal fault of the motor according to the embodiment of the present application;

[0041] Fig. 9is a schematic diagram of a correction process of a motor position signal according to an embodiment of the present application;

[0042] Fig.10 It is another flow chart of the method for determining the position signal fault of a motor according to an embodiment of the present application.

[0043] Description of the main component symbols: control system 10, motor 11, position sensor 12, inverter 13, controller 14, control device 20, acquisition module 21, correction module 22, first calculation module 23, second calculation module 24 and judgment module 25. DETAILED DESCRIPTION

[0044] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0045] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0046] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0047] The disclosure below provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and material examples provided by the present application, but those of ordinary skill in the art can appreciate the application of other processes and / or the use of other materials.

[0048] See also Figure 1 The method for determining the position signal fault of the motor 11 according to the embodiment of the present application includes:

[0049] S10: Acquire an electrical signal output by a position sensor 12, where the position sensor 12 is used to acquire an angle of the motor 11;

[0050] S20: Based on the electrical signal, using a first algorithm to calculate to obtain a first angle θ1 of the motor 11;

[0051] S30: Based on the electrical signal, a second algorithm is used to calculate to obtain a second angle θ2 of the motor 11;

[0052] S40: When the difference between the first angle θ1 and the second angle θ2 is less than or equal to a preset value, it is determined that the position signal of the motor 11 has no fault.

[0053] See also Figure 2 The control system 10 provided in the embodiment of the present application includes a motor 11, a position sensor 12, an inverter 13 and a controller 14. The position sensor 12 is connected to the motor 11. The inverter 13 is connected to the motor 11. The controller 14 is connected to the position sensor 12 and the inverter 13, and the controller 14 is used to implement the above-mentioned method for determining the position signal fault of the motor 11.

[0054] In other words, the controller 14 is used to obtain the electrical signal output by the position sensor 12, and the position sensor 12 is used to obtain the angle of the motor 11; it is also used to calculate, based on the electrical signal, using a first algorithm to obtain a first angle θ1 of the motor 11; it is also used to calculate, based on the electrical signal, using a second algorithm to obtain a second angle θ2 of the motor 11; and it is used to determine that the position signal of the motor 11 is fault-free when the difference between the first angle θ1 and the second angle θ2 is less than or equal to a preset value.

[0055] The vehicle provided in the embodiment of the present application includes the above-mentioned control system 10.

[0056] See also Figure 3The control device 20 provided in the embodiment of the present application includes an acquisition module 21, a first calculation module 23, a second calculation module 24 and a judgment module 25. The acquisition module 21 is used to acquire the electrical signal output by the position sensor 12, and the position sensor 12 is used to acquire the angle of the motor 11. The first calculation module 23 is used to calculate the first angle θ1 of the motor 11 based on the electrical signal using a first algorithm. The second calculation module 24 is used to calculate the second angle θ2 of the motor 11 based on the electrical signal using a second algorithm. The judgment module 25 is used to judge that the position signal of the motor 11 is fault-free when the difference between the first angle θ1 and the second angle θ2 is less than or equal to a preset value.

[0057] In this way, the position sensor 12 signal is diagnosed based on the mathematical characteristics of the electrical signal output by the position sensor 12, and the safety verification of the position sensor 12 is achieved at a relatively low cost, so as to avoid the unexpected torque generation of the vehicle caused by the position signal failure of the motor 11, and ensure the normal driving of the vehicle. No hardware redundancy is required, and self-diagnosis can be performed through the mathematical characteristics of the position sensor 12 signal itself, realizing self-verification of whether the electrical signal is valid and whether the position signal of the motor 11 is faulty, thereby reducing the development cost of the functional safety monitoring of the position sensor 12 and improving the robustness of the control system 10.

[0058] Specifically, most vehicles are driven by permanent magnet synchronous motors 11. When driving, it is necessary to first detect the angular position of the rotor of the motor 11 to adjust the direct-axis current and quadrature-axis current of the motor 11 according to the angular position, thereby changing the output torque of the motor 11. The accuracy of the angular position of the motor 11 will affect the direct-axis current and quadrature-axis current of the motor 11, and the direct-axis current and quadrature-axis current of the motor 11 will affect the output torque of the motor 11. To achieve effective control of the output torque of the motor 11, it is necessary to verify the angle information of the motor 11 in real time to determine whether the position signal of the motor 11 is faulty. This prevents the motor 11 from outputting unexpected torque in the event of a position signal failure, causing a traffic safety accident.

[0059] In step S10, the angle information of the motor 11 is usually detected by a position sensor 12. The position sensor 12 may be an eddy current sensor or a resolver sensor, which is not limited here.

[0060] In one embodiment, the position sensor 12 is an eddy current sensor, which is mounted on the rotating shaft of the motor 11 and rotates synchronously with the motor 11 to sense the angle information of the motor 11. The eddy current sensor may include a transmitting coil and two receiving coils, one receiving coil is used to output a sine signal, and the other receiving coil outputs a cosine signal. The oscillation circuit inside the eddy current sensor forms a sinusoidally changing internal magnetic field through the transmitting coil, and the two receiving coils are located in the oscillating magnetic field, generating an induced electromotive force proportional to the area of ​​the magnetic field. Due to the eddy current effect, the eddy current magnetic field and the source excitation magnetic field of the conductor in the magnetic field are offset, and the target gear position is detected to change with the rotor angle of the motor. The induced voltage of the receiving coil is processed by detection and amplification and finally outputs an electrical signal. The electrical signal may include a sine signal and a cosine signal. The tangent value is calculated according to the sine signal and the cosine signal output by the eddy current sensor 12, and then the corresponding inverse tangent function value is obtained by looking up the table according to the tangent value, thereby obtaining the real-time angle information of the motor 11.

[0061] In step S20 and step S30, based on the electrical signal output by the position sensor 12, different algorithms are used to obtain the angle of the position sensor 12 at the same time, and the difference in the angle of the motor 11 at the same time under the two algorithms is compared. When the difference is greater than a preset value, it can be determined that the position signal of the motor 11 is faulty. Without hardware redundancy, self-diagnosis can be performed by using two different algorithms and the mathematical characteristics of the position sensor 12 signal itself, thereby realizing the verification of whether the position signal of the motor 11 is faulty and reducing the development cost of functional safety monitoring.

[0062] In step S40, when the difference between the first angle θ1 and the second angle θ2 is less than or equal to the preset value, it is determined that the position signal of the motor 11 is fault-free, so that the angular position of the motor 11 can be determined to be accurate. In one embodiment, the preset value is set to 10 degrees. The first angle θ1 of the motor 11 at the 15th ms is calculated to be 35.4 degrees using the first algorithm, and the second angle θ2 of the motor 11 at the 15th ms is calculated to be 36 degrees using the second algorithm. Since the difference between the second angle θ2 and the first angle θ1 is 0.6 degrees, it can be determined that the position signal of the motor 11 is fault-free and the angular position of the motor 11 is accurate.

[0063] It should be noted that after determining that the position signal of the motor 11 is fault-free, the torque request may be obtained first, and then the torque request may be converted into a control instruction according to the first angle θ1 and / or the second angle θ2 of the motor 11. In this way, when it is determined that the position signal of the motor 11 is fault-free, the torque request may be converted into a control instruction for controlling the operation of the motor 11 based on the current position information of the motor 11, so that the vehicle generates the expected torque to ensure normal driving.

[0064] The first algorithm is used to obtain a first angle θ1 of the motor 11 at a certain moment, and the second algorithm is used to obtain a second angle θ2 of the motor 11 at the same moment. When the first angle θ1 is equal to the second angle θ2, the position information of the motor 11 at this moment may be the first angle θ1 or the second angle θ2, and the torque request is converted into a control instruction for controlling the operation of the motor 11 based on the position information of the motor 11 at this moment.

[0065] When the first angle θ1 is different from the second angle θ2, and the difference between the two is less than the preset value, the position information of the motor 11 at that moment can be the first angle θ1 or the second angle θ2, or the average value between the first angle θ1 and the second angle θ2, and the torque request is converted into a control instruction for controlling the operation of the motor 11 based on the position information of the motor 11 at that moment. Figure 4 and Figure 5 In some embodiments, based on the electrical signal, a first algorithm is used to calculate to obtain a first angle θ1 of the motor 11 (step S20), including:

[0066] S21: Based on the electrical signal, a tangent value of a first angle θ1 of the motor 11 is calculated using a first algorithm;

[0067] S22 : Calculate the first angle θ1 of the motor 11 according to the tangent value of the first angle θ1 of the motor 11 .

[0068] In some embodiments, the first calculation module 23 is used to calculate the tangent value of the first angle θ1 of the motor 11 based on the electrical signal using a first algorithm, and is also used to obtain the first angle θ1 of the motor 11 according to the tangent value of the first angle θ1 of the motor 11.

[0069] In some embodiments, the controller 14 is used to calculate the tangent value of the first angle θ1 of the motor 11 based on the electrical signal using a first algorithm, and is also used to obtain the first angle θ1 of the motor 11 according to the tangent value of the first angle θ1 of the motor 11.

[0070] In this way, the tangent value of the first angle θ1 of the motor 11 at a certain moment is calculated using the first algorithm, and the angle corresponding to the tangent value is obtained according to the tangent value, thereby obtaining the angle of the motor 11 at a certain moment.

[0071] Among them, when obtaining the angle of the first angle θ1 of the motor 11 according to the tangent value of the first angle θ1 of the motor 11, it can be obtained by looking up the mapping relationship table between the tangent value and the angle value, or it can be calculated by the inverse tangent trigonometric function, and there is no limitation here.

[0072] In some embodiments, the first algorithm is:

[0073] Among them, θn-1 is the angle of motor 11 at n-1 moments.

[0074] In this way, the ratio of the value of the sine signal to the value of the cosine signal obtained by the position sensor 12 at a certain moment is calculated to obtain the corresponding tangent value, and then the first angle of the motor 11 corresponding to the tangent value can be obtained by table lookup or calculation.

[0075] In one embodiment, at the 12th ms, the value of the sine signal output by the position sensor 12 is 0.5, the value of the cosine signal output by the position sensor 12 is √3 / 2, and the tangent value of the first angle θ1 of the motor 11 is √3 / 3 calculated according to the first algorithm. The table can be looked up later based on the tangent value, and it can be concluded that the first angle θ1 of the motor 11 at the 12th ms is 30 degrees.

[0076] See also Figure 4 and Figure 6 In some embodiments, based on the electrical signal, a second algorithm is used to calculate to obtain a second angle θ2 of the motor 11 (step S30), including:

[0077] S31: Based on the electrical signal, a tangent value of a second angle θ2 of the motor 11 is calculated using a second algorithm;

[0078] S32 : Calculate the second angle θ2 of the motor 11 according to the tangent value of the second angle θ2 of the motor 11 .

[0079] In some embodiments, the second calculation module 24 is used to calculate the tangent value of the second angle θ2 of the motor 11 based on the electrical signal using a second algorithm; and is also used to calculate the second angle θ2 of the motor 11 according to the tangent value of the second angle θ2 of the motor 11.

[0080] In some embodiments, the controller 14 is used to calculate the tangent value of the second angle θ2 of the motor 11 based on the electrical signal using a second algorithm; and is also used to calculate the second angle θ2 of the motor 11 according to the tangent value of the second angle θ2 of the motor 11.

[0081] In this way, the electrical signal of the position sensor 12 is obtained, the tangent value corresponding to the angle of the motor 11 at a certain moment is calculated, and the angle corresponding to the tangent value is obtained based on the tangent value, thereby obtaining the angle of the motor 11 at a certain moment.

[0082] Among them, when obtaining the second angle θ2 of the motor 11 according to the tangent value of the second angle θ2 of the motor 11, the second angle θ2 of the motor 11 can be obtained by looking up the mapping relationship table between the tangent value and the angle value, or it can be calculated by the inverse tangent trigonometric function, and there is no limitation here.

[0083] In some embodiments, the second algorithm is:

[0084] Among them, θ n is the angle of motor 11 at time n, θ n-1 is the angle of motor 11 at time n-1, θ n-2 is the angle of motor 11 at time n-2.

[0085] In this way, the values ​​of the sine signal and the cosine signal obtained by the position sensor 12 at the nth moment and the n-2th moment are obtained, and the tangent value corresponding to the angle of the motor 11 at the n-1th moment is calculated, and then the second angle θ2 of the motor 11 corresponding to the tangent value can be obtained by table lookup or calculation.

[0086] Specifically, the difference between the sine signal and cosine signal of the motor 11 at the nth moment and the n-2th moment is calculated respectively. Since the interval between the two moments is short, the above sine difference and cosine difference can be approximately regarded as the sine and cosine differential values ​​at the n-1 moment. Therefore, the second algorithm can be used to obtain the angle tangent value of the motor 11 at the n-1th moment, and then the angle of the motor 11 at the n-1th moment can be obtained by looking up the table.

[0087] In one embodiment, at 12 ms, the value of the sine signal output by the position sensor 12 is 0.5, and the value of the cosine signal output by the position sensor 12 is 0.866. At 14 ms, the value of the sine signal output by the position sensor 12 is 0.642, and the value of the cosine signal output by the position sensor 12 is 0.766. According to the second calculation algorithm, the tangent value corresponding to the second angle θ2 is 0.704. Subsequently, according to the tangent value, it can be found in the table that the second angle θ2 of the motor 11 at 12 ms is 35.15 degrees.

[0088] See also Figure 4 and Figure 7 In some embodiments, the method for determining the position signal fault of the motor 11 includes:

[0089] S50: within a preset time, when the difference between the first angle θ1 and the second angle θ2 is greater than a preset value, it is determined that the position signal of the motor 11 is faulty.

[0090] In some embodiments, the determination module 25 is configured to determine that the position signal of the motor 11 is faulty when the difference between the first angle θ1 and the second angle θ2 is greater than a preset value within a preset time.

[0091] In some embodiments, the controller 14 is configured to determine that the position signal of the motor 11 is faulty when the difference between the first angle θ1 and the second angle θ2 is greater than a preset value within a preset time.

[0092] Thus, within the preset time, when the difference between the first angle θ1 and the second angle θ2 is greater than the preset value, it can be determined that the position signal of the motor 11 is faulty. The preset time can be set by the user. It should be noted that when the position signal of the motor 11 is faulty, the control system 10 can output the fault state of the position signal of the motor 11 to facilitate the user to perform maintenance.

[0093] In one embodiment, the preset time is set to 200ms, and the preset value is set to 10 degrees. At 15ms, the value of the sine signal output by the position sensor 12 is 1 / 2, and the value of the cosine signal output by the position sensor 12 is 0.866. According to the first algorithm, the tangent value of the first angle θ1 of the motor 11 is 0.577. Subsequently, according to the tangent value table lookup, it can be concluded that the first angle θ1 of the motor 11 at 15ms is 29.99 degrees.

[0094] At the 14th ms, the value of the sine signal output by the position sensor 12 is 0.656, and the value of the cosine signal output by the position sensor 12 is 0.755. At the 16th ms, the value of the sine signal output by the position sensor 12 is 0.707, and the value of the cosine signal output by the position sensor 12 is 0.707. According to the second calculation algorithm, it can be obtained that the tangent value corresponding to the second angle θ2 at the 15th ms is 0.941. Subsequently, according to the tangent value table lookup, it can be obtained that the second angle θ2 of the motor 11 at the 15th ms is 43.26 degrees. At the 15th ms, the difference between the first angle θ1 and the second angle θ2 of the motor 11 is 13.27 degrees, and the difference between the first angle θ1 and the second angle θ2 of the motor 11 is always greater than 10 degrees for 200 ms, so that it can be judged that the position signal of the motor 11 is faulty.

[0095] See also Figure 8 In some embodiments, before calculating the first angle θ1 of the motor 11 using the first algorithm based on the electrical signal (step S20), the method for determining the position signal fault of the motor 11 further includes:

[0096] S15: Correct the electrical signal.

[0097] In some embodiments, the control device 20 may further include a correction module 22, and the correction module 22 is used to correct the electrical signal.

[0098] In certain embodiments, controller 14 is configured to modify the electrical signal.

[0099] In this way, the error of the electrical signal output by the correction position sensor 12 is eliminated to obtain a standardized sine-cosine curve signal, thereby facilitating subsequent verification of the electrical signal to determine whether the position signal of the motor 11 is faulty.

[0100] It is understandable that, when the motor 11 is working and the position sensor 12 detects the angle of the motor 11, the position sensor 12 may be subject to electromagnetic interference or the stability or accuracy of the position sensor 12 itself may be affected, resulting in the electrical signal obtained by the position sensor 12 being a non-standard sine-cosine curve. The purpose of the correction is to convert the non-standard sine-cosine curve into a standard sine-cosine curve through correction.

[0101] Specifically, the maximum and minimum values ​​of the sine voltage signal and the cosine voltage signal within a cycle can be obtained first, and then the sine voltage value and the cosine voltage signal are normalized according to the maximum and minimum values ​​to obtain the normalized sine voltage signal and the cosine voltage signal, and the amplitude range of the sine voltage signal and the cosine voltage signal can be controlled between [-1, 1]. After correcting the electrical signal, the corrected sine signal and the cosine signal can be obtained.

[0102] In some embodiments, correcting the electrical signal may include correcting the amplitude of the electrical signal and correcting the deviation of the electrical signal. That is, the correction parameters required for the electrical signal include the amplitude and deviation of the output value of the position sensor 12. In one embodiment, the electrical signal obtained by the position sensor 12 is as follows: Fig. 9 (A), where the deviation refers to the difference between the mean value of the electrical signal output and the 0 position of the vertical axis, and the amplitude is half of the difference between the maximum value and the minimum value of the electrical signal output. The corrected electrical signal of the position sensor 12 is as follows: Fig. 9 (B) shown.

[0103] Understandably, see Fig.10 , obtain the sine signal and cosine signal output by the position sensor 12, calculate the maximum and minimum values ​​of the sine signal in one cycle, and then perform deviation calculation and amplitude calculation, and at the same time calculate the maximum and minimum values ​​of the cosine signal in one cycle, and then perform deviation calculation and amplitude calculation, so as to correct the sine signal and cosine signal. Based on the corrected sine signal and cosine signal, use the first algorithm to calculate to obtain the tangent value of the first angle θ1 of the motor 11 at a certain moment, and then look up the table according to the tangent value to obtain the corresponding first angle θ1, and use the second algorithm to calculate to obtain the tangent value of the second angle θ2 of the motor 11 at the same moment, and then look up the table according to the tangent value to obtain the corresponding second angle θ2.

[0104] The signal is checked according to the difference between the first angle θ1 and the second angle θ2. When the difference between the first angle θ1 and the second angle θ2 is less than or equal to the preset value, it is determined that the position signal of the motor 11 is fault-free. Within the preset time, when the difference between the first angle θ1 and the second angle θ2 is less than or equal to the preset value, it is determined that the position signal of the motor 11 is faulty. The control system 10 can then output the angle fault state for the user to view and repair.

[0105] In this way, by correcting the electrical signal output by the position sensor 12, it is convenient to subsequently calculate the angle of the motor 11 at the same time through two algorithms, and determine whether the position signal of the motor 11 is faulty based on the difference between the two angle values.

[0106] In summary, by acquiring the electrical signal output by the position sensor 12, based on the electrical signal, the first angle θ1 of the motor 11 is calculated using the first algorithm, and the second angle θ2 of the motor 11 is calculated using the second algorithm. The first angle θ1 and the second angle θ2 are calculated. When the difference between the first angle θ1 and the second angle θ2 is less than or equal to the preset value, it is determined that the position signal of the motor 11 is fault-free. Based on the current position information of the motor 11, the torque request input to the controller 14 is converted into a control instruction to control the operation of the motor 11. Within the preset time, when the difference between the first angle θ1 and the second angle θ2 is greater than the preset value, it is determined that the position signal of the motor 11 is faulty. When the position signal of the motor 11 is faulty, the control system 10 can output the fault state of the position signal of the motor 11 to facilitate the user to perform maintenance.

[0107] Without the need for hardware redundancy, self-diagnosis can be performed through the mathematical characteristics of the position sensor 12 signal itself, realizing self-verification of whether the electrical signal is valid and whether the position signal of the motor 11 is faulty, thereby reducing the development cost of functional safety monitoring of the position sensor 12 and improving the robustness of the control system 10. The safety verification of the position sensor 12 can be achieved at a lower cost, and unexpected torque can be avoided during the power output process of the vehicle, ensuring normal driving of the vehicle.

[0108] In the description of this specification, the description with reference to the terms "one embodiment", "certain embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0109] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for determining a motor position signal fault, characterized in that: include: Acquire an electrical signal output by a position sensor, wherein the position sensor is used to acquire the angle of the motor; Based on the electrical signal, using a first algorithm to calculate to obtain a first angle of the motor; Based on the electrical signal, using a second algorithm to calculate to obtain a second angle of the motor; When the difference between the first angle and the second angle is less than or equal to a preset value, it is determined that the position signal of the motor has no fault; The second algorithm is: Among them, θ n is the angle of the motor at time n, θ n-1 is the angle of the motor at time n-1, θ n-2 is the angle of the motor at time n-2.

2. The method for determining a motor position signal fault according to claim 1, characterized in that: The step of calculating based on the electrical signal using a first algorithm to obtain a first angle of the motor includes: Based on the electrical signal, a tangent value of a first angle of the motor is calculated using a first algorithm; The first angle of the motor is obtained according to a tangent value of the first angle of the motor.

3. The method for determining a motor position signal fault according to claim 1, characterized in that: The first algorithm is: Among them, θ n-1 is the angle of the motor 11 at n-1 seconds.

4. The method for determining a motor position signal fault according to claim 1, characterized in that: The step of calculating based on the electrical signal using a second algorithm to obtain a second angle of the motor includes: Based on the electrical signal, a tangent value of a second angle of the motor is calculated using a second algorithm; The second angle of the motor is obtained according to the tangent value of the second angle of the motor.

5. The method for determining a motor position signal fault according to claim 1, characterized in that: The method for determining a position signal fault of a motor comprises: Within a preset time, when the difference between the first angle and the second angle is greater than the preset value, it is determined that the position signal of the motor is faulty.

6. The method for determining a motor position signal fault according to claim 1, characterized in that: Before calculating based on the electrical signal using a first algorithm to obtain a first angle of the motor, the method for determining a position signal fault of the motor further includes: The electrical signal is modified.

7. A control device, characterized in that: include: An acquisition module, used to acquire an electrical signal output by a position sensor, wherein the position sensor is used to acquire the angle of the motor; A first calculation module, configured to calculate a first angle of the motor based on the electrical signal using a first algorithm; A second calculation module, configured to calculate, based on the electrical signal, using a second algorithm to obtain a second angle of the motor; A judging module, configured to judge that the position signal of the motor has no fault when the difference between the first angle and the second angle is less than or equal to a preset value; The second algorithm is: Among them, λ n is the angle of the motor at time n, λ n-1 is the angle of the motor at time n-1, θ n-2 is the angle of the motor at time n-2.

8. A control system, characterized in that: include: Motor; A position sensor connected to the motor; An inverter connected to the motor; and A controller, wherein the controller is connected to the position sensor and the inverter, and the controller is used to implement the motor position signal fault judgment method according to any one of claims 1 to 6.

9. A vehicle, characterized in that: Includes the control system described in claim 8.

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