Angular position calibration system and control method for synchronous permanent magnet motor rotor

Abstract

The present invention relates to an angular position calibration system for a synchronous permanent magnet motor rotor, comprising a magnetoelectric eddy current sensor, a sensor, and a signal wheel rotor. The present invention also relates to a control method, comprising the steps of: performing output signal voltage range detection; performing output signal common mode voltage detection; performing amplitude normalization detection; and performing differential consistency detection. The present invention simplifies the sensor structure and reduces manufacturing costs; does not require a special RDC decoder; has low energy consumption; realizes differential analog signal output, reduces common mode noise interference, and improves reliability; and develops a suitable algorithm to improve the safety and reliability of the sensor.

Description

Technical Field

[0001] The invention relates to the field of motor control, and in particular to an angular position calibration system and a control method for a synchronous permanent magnet motor rotor. Background Art

[0002] As an irreplaceable component of hybrid electric vehicles, the synchronous permanent magnet motor plays an important role in which the angle position sensor plays an important role. The control of the permanent magnet synchronous motor is based on the precise control of the rotor pole angle and the current phase of the stator coil to ensure the relevant speed / torque control. In order to make it operate normally and efficiently, the angle position sensor must be able to accurately measure the rotation angle of the rotor, thereby controlling the phase of the three-phase current in the stator winding, so that the corresponding coupling electromagnetic torque is generated in the motor and the rotor is operated with maximum efficiency.

[0003] like Figure 1 As shown in the figure, the permanent magnet synchronous motor of electric vehicles currently usually uses a resolver sensor (resolver) to calibrate the angular position of the rotor. A resolver sensor is a signal element whose output voltage changes with the rotor angle. When the excitation winding is excited by an AC voltage of a certain frequency, the voltage amplitude of the output winding is in a sine or cosine function relationship with the rotor angle, or maintains a certain proportional relationship, or is in a linear relationship with the angle within a certain angle range. The resolver is composed of a rotor and a stator winding, and the two are independent of each other. The primary and secondary coils are both wound on the stator. The rotor consists of two sets of coils with a 90° difference. It adopts a brushless design, and the rotor and stator are separated.

[0004] The defects of the prior art are:

[0005] 1. The sensor structure is complex and the manufacturing cost is high;

[0006] 2. A special RDC decoder needs to be matched to realize resolver decoding;

[0007] 3. High energy consumption;

[0008] 4. The functional safety level cannot meet ASIL-C. Summary of the invention

[0009] In view of the above problems, the present invention provides a synchronous permanent magnet motor rotor angular position calibration system and control method, the purpose of which is to simplify the sensor structure and reduce manufacturing costs; do not require a special RDC decoder; have low energy consumption; achieve differential analog signal output, reduce common mode noise interference, and improve reliability; and develop a suitable algorithm to improve the safety and reliability of the sensor.

[0010] To solve the above problems, the technical solution provided by the present invention is:

[0011] A synchronous permanent magnet motor rotor angular position calibration system, comprising a magnetoelectric eddy current sensor; the magnetoelectric eddy current sensor is used to provide a differential Sin+ output signal, a Sin- output signal, a Cos+ output signal, and a Cos- output signal; the magnetoelectric eddy current sensor comprises a sensor and a signal wheel rotor; wherein:

[0012] The signal wheel rotor is used to generate eddy current on its surface; the signal wheel rotor is made of conductive material;

[0013] The sensor includes a PCB; the PCB includes a primary excitation current coil and a secondary coil; wherein:

[0014] The secondary coil is used for receiving the eddy current magnetic field.

[0015] Preferably, the primary excitation current coil is connected to a capacitor with a fixed capacitance value; the primary excitation current coil is excited by a high-frequency current signal generated by the integrated chip drive on the PCB to form a high-frequency oscillation circuit; the high-frequency oscillation circuit generates a changing magnetic field near the primary excitation current coil, which is mutually coupled with the secondary coil.

[0016] Preferably, the secondary coil comprises two groups of independent windings; the two groups of independent windings respectively generate a Sine output voltage signal and a Cosine output voltage signal with a phase shift of 90° electrical angle relative to each other;

[0017] The two sets of independent windings are wound in Sine and Cosine waveform geometries;

[0018] Preferably, the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal provided by the magnetoelectric eddy current sensor are further subjected to an optimization processing flow to obtain optimized differential forms of the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal;

[0019] The optimization process thus includes a modulation and demodulation sub-process, an automatic gain control sub-process, and a high-voltage output protection sub-process.

[0020] Preferably, the optimized Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal are processed by the ECU to obtain a Sin_diff differential signal and a Cos_diff differential signal.

[0021] A method for controlling the angular position of a synchronous permanent magnet motor rotor using the above-mentioned angular position calibration system of the synchronous permanent magnet motor rotor comprises the following steps:

[0022] S100. Perform output signal voltage range detection; then perform the following operations based on the detection result:

[0023] If the detection result of the output signal voltage range detection is that the output signal is within the manually preset normal voltage range, executing S200;

[0024] If the detection result of the output signal voltage range detection is that the output signal is not within the normal voltage range, an abnormal signal alarm and a maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method is terminated;

[0025] S200. Perform output signal common mode voltage detection; then perform the following operations according to the detection result:

[0026] If the detection result of the output signal common mode voltage detection is that the common mode values ​​of the Sin+ output signal and the Sin- output signal after low-pass filtering meet the manually preset common mode value qualification condition, and the common mode values ​​of the Cos+ output signal and the Cos- output signal after low-pass filtering meet the common mode value qualification condition, execute S300;

[0027] If the detection result of the output signal common mode voltage detection is that the common mode values ​​of the Sin+ output signal and the Sin- output signal after low-pass filtering do not meet the common mode value qualification condition, or the common mode values ​​of the Cos+ output signal and the Cos- output signal after low-pass filtering do not meet the common mode value qualification condition, then the signal abnormality alarm and the maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method is terminated;

[0028] S300. Perform amplitude normalization detection; then perform the following operations based on the detection results:

[0029] If the detection result of the amplitude normalization detection is that the amplitude meets the manually preset amplitude normalization qualification condition, executing S400;

[0030] If the detection result of the amplitude normalization detection is that the amplitude does not meet the amplitude normalization qualification condition, the abnormal signal alarm and the maintenance request alarm are issued; then the process of the angle position control method of the synchronous permanent magnet motor rotor is terminated;

[0031] S400. Perform differential consistency detection; then perform the following operations based on the detection results:

[0032] If the detection result of the differential consistency detection is that the differential consistency does not exceed the manually preset differential consistency threshold, a detection qualified signal is issued; and then the process of the angle position control method of the synchronous permanent magnet motor rotor is ended;

[0033] If the detection result of the differential consistency detection is that the differential consistency exceeds the differential consistency threshold, the magnetoelectric eddy current sensor is placed in a safety diagnosis mode.

[0034] Preferably, the output signal voltage range detection in S100 specifically includes the following steps:

[0035] S110. Continuously collect the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal; then obtain the maximum value and the minimum value of the output signal;

[0036] S120. Detect the power supply voltage; then perform the following operations according to the value of the power supply voltage:

[0037] If the power supply voltage is 5V, execute S130;

[0038] If the power supply voltage is not 5V, return to and execute S110 again;

[0039] S130. The ECU detects whether the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, performs the following operations:

[0040] If the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V, execute S140;

[0041] If the maximum value of the output signal obtained in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range;

[0042] S140. The ECU detects whether the minimum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, performs the following operations:

[0043] If the minimum value of the output signal obtained in S110 is between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal being within the normal voltage range;

[0044] If the minimum value of the output signal acquired in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range.

[0045] Preferably, the common mode value of the Sin+ output signal and the Sin- output signal in S200 is expressed as follows:

[0046] Sin_com=(Sin+)+(Sin-)

[0047] Wherein: Sin_com is the common mode value of the Sin+ output signal and the Sin- output signal; Sin+ is the collected value of the Sin+ output signal; Sin- is the collected value of the Sin- output signal;

[0048] The common mode value of the Cos+ output signal and the Cos- output signal in S200 is expressed as follows:

[0049] Cos_com=(Cos+)+(Cos-)

[0050] Wherein: Cos_com is the common mode value of the Cos+ output signal and the Cos- output signal; Cos+ is the collected value of the Cos+ output signal; Cos- is the collected value of the Cos- output signal; the common mode value qualified condition in S200 is expressed as follows:

[0051]

[0052] Wherein: Vcc is the power supply voltage; Sin_com_filtered is the common mode value of the Sin+ output signal and the Sin- output signal after low-pass filtering; Cos_com_filtered is the common mode value of the Cos+ output signal and the Cos- output signal after low-pass filtering.

[0053] Preferably, the amplitude normalization qualification condition in S300 is expressed as follows:

[0054] 1-error≤Sin 2 (θ)+Cos 2 (θ)≤1+error

[0055] Where: error is the accuracy compensation, which is preset manually; θ is the position angle of the rotor; Sin(θ) is the output signal obtained after offset compensation and amplitude normalization of Sin+ or Sin-; Cos(θ) is the output signal obtained after offset compensation and amplitude normalization of Cos+ or Cos-;

[0056] The Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal are expressed as follows:

[0057]

[0058] Where: Vps is the amplitude of the single-ended output signal Sin+ or Sin-; Vpc is the amplitude of the single-ended output signal Cos+ or Cos-; Vos is the bias voltage of the single-ended output signal Sin+ or Sin-; Voc is the bias voltage of the single-ended output signal Cos+ or Cos-;

[0059] Sin(θ) and Cos(θ) are expressed as follows:

[0060]

[0061] Wherein: Sin_diff is the Sin_diff differential signal; Cos_diff is the Cos_diff differential signal; Sin_diff and Cos_diff are expressed as follows:

[0062]

[0063] Offset_Sin and offset_Cos are bias voltages, expressed as follows:

[0064]

[0065] Amplitude_Sin and Amplitude_Cos are the voltage amplitudes, expressed as follows:

[0066]

[0067] Preferably, the differential consistency detection in S400 specifically includes the following steps:

[0068] S410. Obtaining the actual rotor mechanical speed and the number of motor pole pairs of the motor;

[0069] S420. The electrical angle frequency of the motor rotor rotation is calculated based on the actual mechanical speed of the motor rotor and the number of motor pole pairs, and is expressed as follows:

[0070] f el =rotor_speed*Npp / 60

[0071] Where: f el is the electrical angle frequency of the motor rotor rotation, in Hz; rotor_speed is the actual rotor mechanical speed of the motor, in rpm; Npp is the number of motor pole pairs, in s / min;

[0072] S430. Set the sampling frequency; the sampling frequency is an integer multiple of the electrical angle frequency of the motor rotor rotation, expressed as follows:

[0073] f s=N*f el

[0074] Where: f s is the sampling frequency; N is a multiple;

[0075] S440. After sampling through ADC analog-to-digital conversion, the differential signal is calculated and expressed as follows:

[0076]

[0077] Where: ΔSin(n) and ΔCos(n) are both differential signals; n is the number of sampling times;

[0078] S450. Calculate the rotor position angle and express it as follows:

[0079]

[0080] S460. Compare the consistency between the signals Sin(n-1), Cos(n-1) and the differential signals ΔCos(n), ΔSin(n), expressed as follows:

[0081] abs(θest(n)-θout(n-1))<threshold

[0082] Wherein: threshold is the differential consistency threshold.

[0083] Compared with the prior art, the present invention has the following advantages:

[0084] 1. The present invention simplifies the sensor structure and reduces the manufacturing cost;

[0085] 2. The present invention does not require a dedicated RDC decoder;

[0086] 3. The present invention has low energy consumption;

[0087] 4. The present invention realizes differential analog signal output, reduces common mode noise interference, and improves reliability;

[0088] 5. The present invention develops a suitable algorithm to improve the safety and reliability of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 A schematic diagram of a rotary sensor used in the prior art in the background technology;

[0090] Figure 2 A schematic diagram of the relationship between the primary coil and the secondary coil on the PCB board of the eddy current sensor according to a specific embodiment of the present invention;

[0091] Figure 3A schematic diagram of an output signal of an eddy current sensor according to a specific embodiment of the present invention;

[0092] Figure 4 It is a schematic diagram of a flow chart of ECU output signal processing according to a specific embodiment of the present invention;

[0093] Figure 5 It is a schematic diagram of the ECU output signal control strategy of a specific embodiment of the present invention. DETAILED DESCRIPTION

[0094] The present invention is further explained below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0095] A synchronous permanent magnet motor rotor angular position calibration system comprises a magnetoelectric eddy current sensor.

[0096] like Figure 2 As shown, the magnetoelectric eddy current sensor is used to provide a differential Sin+ output signal, a Sin- output signal, a Cos+ output signal, and a Cos- output signal; the magnetoelectric eddy current sensor includes a sensor and a signal wheel rotor; wherein:

[0097] The signal wheel rotor is used to generate eddy current on its surface; the signal wheel rotor is made of conductive material.

[0098] In this specific embodiment, the signal wheel rotor is made of aluminum or steel.

[0099] The sensor includes a PCB; the PCB includes a primary excitation current coil and a secondary coil; wherein:

[0100] The secondary coil is used to receive the eddy current magnetic field.

[0101] In this specific embodiment, the primary excitation current coil is connected to a capacitor with a fixed capacitance value; the primary excitation current coil is excited by a high-frequency current signal generated by the integrated chip drive on the PCB to form a high-frequency oscillation circuit;

[0102] The high frequency oscillation circuit generates a changing magnetic field near the primary excitation current coil, which is mutually coupled with the secondary coil.

[0103] In this specific embodiment, the secondary coil includes two sets of independent windings; the two sets of independent windings respectively generate a Sine output voltage signal and a Cosine output voltage signal with a phase shift of 90° electrical angle relative to each other.

[0104] Two independent windings are wound in Sine and Cosine waveform geometries.

[0105] It should be noted that the two sets of independent windings are wound in Sine and Cosine waveform geometry in order to generate signal outputs that are Sine and Cosine functions of the rotor angular position.

[0106] It needs to be further explained that if Figure 3 As shown in the figure, when the conductive signal wheel passes through the winding coil, eddy currents will be generated on the signal wheel, and the reverse magnetic field generated by the eddy currents can be detected by two sets of independent secondary coils. When the rotor angle changes, the corresponding Sine and Cosine voltage signals will be output accordingly.

[0107] It should be further explained that the reason why the magnetoelectric eddy current sensor provides the Sin+ output signal, Sin- output signal, Cos+ output signal, and Cos- output signal is that the differential form can effectively eliminate the noise interference from the common mode form of the output end.

[0108] In this specific embodiment, the original Sin+ output signal, Sin- output signal, Cos+ output signal, and Cos- output signal provided by the magnetoelectric eddy current sensor need to be further processed to obtain the rotor angle and meet the accuracy requirements, that is, through the optimization processing flow, the optimized differential form of Sin+ output signal, Sin- output signal, Cos+ output signal, and Cos- output signal are obtained to obtain the rotor angle and meet the accuracy requirements.

[0109] The optimization process begins with the processing of the output signal inside the chip, which goes through the modulation and demodulation sub-process, the automatic gain control sub-process, and the high-voltage output protection sub-process respectively.

[0110] like Figure 4 As shown, in this specific embodiment, the optimized Sin+ output signal, Sin- output signal, Cos+ output signal, and Cos- output signal need to be further processed by the ECU to obtain the Sin_diff differential signal and the Cos_diff differential signal.

[0111] It should be noted that the purpose of this step is to eliminate the common-mode signal noise at the output signal end and the errors generated during the sensor assembly process, thereby improving the final output accuracy of the sensor.

[0112] It needs to be further explained that if Figure 5 As shown in the figure, in order to improve the reliability of the sensor and meet the automotive-grade functional safety level ASIL-C requirements, it is necessary to implant a new control strategy on the ECU side.

[0113] It should be further explained that the improvement of the sensor in the present invention is aimed at simplifying the sensor structure and reducing the manufacturing cost. We have developed a new type of eddy current sensor. The eddy current sensor uses eddy current formation to determine displacement. It is formed when a changing magnetic field intersects a conductor. The relative motion causes a circulating flow of electrons or electrons in the conductor. These circulating eddy currents of the electromagnet with a magnetic field can resist the influence of the external magnetic field.

[0114] When the conductive signal wheel passes through the winding coil, eddy currents are generated on the signal wheel. The reverse magnetic field generated by the eddy currents can be detected by two sets of independent secondary coils. When the rotor angle changes, a corresponding set of Sine and Cosine voltage signals will be output accordingly. By taking the inverse tangent of the reorganized signal, the angular position of the rotor can be obtained.

[0115] The sensor has low energy consumption, can realize differential analog signal output, reduce common mode noise interference, improve reliability and accuracy, and does not require a dedicated RDC decoder.

[0116] The functional safety level of the on-board motor rotor position sensor must meet the automotive-grade requirement ASIL-C, so a control strategy needs to be developed for the eddy current sensor to improve its safety and reliability.

[0117] A method for controlling the angular position of a synchronous permanent magnet motor rotor using the angular position calibration system of the synchronous permanent magnet motor rotor comprises the following steps:

[0118] S100. Perform output signal voltage range detection; then perform the following operations based on the detection result:

[0119] If the detection result of the output signal voltage range detection is that the output signal is within the manually preset normal voltage range, S200 is executed.

[0120] If the output signal voltage range detection result is that the output signal is not within the normal voltage range, an abnormal signal alarm and a maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method ends.

[0121] In this specific embodiment, the output signal voltage range detection in S100 specifically includes the following steps:

[0122] S110. Continuously collect the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal; then obtain the maximum value and the minimum value of the output signal.

[0123] like Figure 4As shown, when the ASIC detects an internal fault in the sensor, the output signal is switched to a high-impedance output. Since a lower-impedance pull-up resistor is connected to the ECU end, the output signal voltage is very close to the supply voltage Vcc (>4.75V when Vcc=5V).

[0124] S120. Detect the power supply voltage; then perform the following operations according to the value of the power supply voltage:

[0125] If the value of the power supply voltage is 5V, ie, Vcc=5V, S130 is executed.

[0126] If the value of the power supply voltage is not 5V, that is, Vcc≠5V, the process returns to and executes S110 again.

[0127] S130. The ECU detects whether the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, the following operations are performed:

[0128] If the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V, execute S140;

[0129] If the maximum value of the output signal acquired in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range.

[0130] S140. The ECU detects whether the minimum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, the following operations are performed:

[0131] If the minimum value of the output signal acquired in S110 is between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal being within the normal voltage range.

[0132] If the minimum value of the output signal acquired in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range.

[0133] S200. Perform output signal common mode voltage detection; then perform the following operations according to the detection result:

[0134] If the detection result of the output signal common mode voltage detection is that the common mode values ​​of the Sin+ output signal and the Sin- output signal after low-pass filtering meet the manually preset common mode value qualification conditions, and the common mode values ​​of the Cos+ output signal and the Cos- output signal after low-pass filtering meet the common mode value qualification conditions, execute S300.

[0135] If the detection result of the output signal common mode voltage detection is that the common mode value of the Sin+ output signal and the Sin- output signal after low-pass filtering does not meet the common mode value qualification condition, or the common mode value of the Cos+ output signal and the Cos- output signal after low-pass filtering does not meet the common mode value qualification condition, then an abnormal signal alarm and a maintenance request alarm are issued; then the process of the angle position control method of the synchronous permanent magnet motor rotor is terminated.

[0136] In this specific embodiment, the common mode value of the Sin+ output signal and the Sin- output signal in S200 is expressed by formula (1):

[0137] Sin_com=(Sin+)+(Sin-)(1)

[0138] Wherein: Sin_com is the common mode value of the Sin+ output signal and the Sin- output signal; Sin+ is the acquisition value of the Sin+ output signal; Sin- is the acquisition value of the Sin- output signal.

[0139] The common mode value of the Cos+ output signal and the Cos- output signal in S200 is expressed by formula (2):

[0140] Cos_com=(Cos+)+(Cos-)(2)

[0141] Wherein: Cos_com is the common mode value of the Cos+ output signal and the Cos- output signal; Cos+ is the acquisition value of the Cos+ output signal; Cos- is the acquisition value of the Cos- output signal.

[0142] The qualified condition of the common mode value in S200 is expressed as follows:

[0143]

[0144] Wherein: Vcc is the power supply voltage; Sin_com_filtered is the common mode value of the Sin+ output signal and the Sin- output signal after low-pass filtering; Cos_com_filtered is the common mode value of the Cos+ output signal and the Cos- output signal after low-pass filtering.

[0145] It should be noted that since each group of signals Sin+, Cos+ has reverse outputs Sin-, Cos-, that is, the amplitudes of Sin+ (Cos+) and Sin- (Cos-) are equal, and the phase difference is 180°, theoretically, the common mode value of Sin+ (Cos+) and Sin- (Cos-) is equal to the power supply Vcc.

[0146] S300. Perform amplitude normalization detection; then perform the following operations based on the detection results:

[0147] If the detection result of the amplitude normalization detection is that the amplitude meets the manually preset amplitude normalization qualification condition, S400 is executed.

[0148] If the amplitude normalization detection result is that the amplitude does not meet the amplitude normalization qualification condition, an abnormal signal alarm and a maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method is terminated.

[0149] In this specific embodiment, the amplitude normalization qualification condition in S300 is expressed as follows:

[0150] 1-error≤Sin 2 (θ)+Cos 2 (θ)≤1+error(4)

[0151] Wherein: error is the accuracy compensation amount, which is preset manually; θ is the position angle of the rotor; Sin(θ) is the output signal obtained after offset compensation and amplitude normalization of Sin+ or Sin-; Cos(θ) is the output signal obtained after offset compensation and amplitude normalization of Cos+ or Cos-.

[0152] It should be noted that, in theory, the sum of the squares of normalized Sin(θ) and Cos(θ) should be 1. However, due to the sensor's own errors and line interference, it is impossible to obtain ideal Sin(θ) and Cos(θ) curves, so it is necessary to detect whether Sin(θ) and Cos(θ) satisfy equation (4) in the ECU.

[0153] It should be further explained that error is the accuracy compensation amount, which is preset manually and can be adjusted and determined according to actual accuracy requirements. It can generally be set in the range of 0.05 to 0.15.

[0154] The Sin+ output signal, Sin- output signal, Cos+ output signal, and Cos- output signal are expressed as follows:

[0155]

[0156] Wherein: Vps is the amplitude of the single-ended output signal Sin+ or Sin-; Vpc is the amplitude of the single-ended output signal Cos+ or Cos-; Vos is the bias voltage of the single-ended output signal Sin+ or Sin-; Voc is the bias voltage of the single-ended output signal Cos+ or Cos-.

[0157] Sin(θ) and Cos(θ) are expressed as follows:

[0158]

[0159] Where: Sin_diff is the Sin_diff differential signal; Cos_diff is the Cos_diff differential signal; Sin_diff and Cos_diff are expressed according to formula (7):

[0160]

[0161] Offset_Sin and offset_Cos are bias voltages, expressed as follows:

[0162]

[0163] Amplitude_Sin and Amplitude_Cos are the voltage amplitudes, expressed as follows:

[0164]

[0165] S400. Perform differential consistency detection; then perform the following operations based on the detection results:

[0166] If the detection result of the differential consistency detection is that the differential consistency does not exceed the manually preset differential consistency threshold, a detection pass signal is issued; then the process of the synchronous permanent magnet motor rotor angle position control method ends.

[0167] If the detection result of the differential consistency detection is that the differential consistency exceeds the differential consistency threshold, the magnetoelectric eddy current sensor is placed in a safety diagnosis mode.

[0168] In this specific embodiment, the differential consistency detection in S400 specifically includes the following steps:

[0169] S410. Obtain the actual rotor mechanical speed of the motor and the number of motor pole pairs.

[0170] S420. The electrical angle frequency of the motor rotor rotation is calculated based on the actual motor rotor mechanical speed and the motor pole pair number, and is expressed as follows:

[0171] f el = rotor_speed*Npp / 60(10)

[0172] Where: f el is the electrical angle frequency of the motor rotor rotation, in Hz; rotor_speed is the actual mechanical speed of the motor rotor, in rpm; Npp is the number of motor pole pairs, in s / min.

[0173] It should be noted that f el It is the frequency of the output signals Sin(θ) and Cos(θ), that is, the electrical angle frequency of the motor rotor rotation.

[0174] S430. Set the sampling frequency; the sampling frequency is an integer multiple of the electrical angle frequency of the motor rotor rotation, expressed as formula (11):

[0175] f s =N*f el (11)

[0176] Where: f s is the sampling frequency; N is the multiple.

[0177] It should be noted that the sampling frequency f s The electrical angle frequency f of the motor rotor rotation el The sampling step length is an integral multiple of 360° / N. For example, when N=120, the sampling step length is 3°. The larger the N value, the higher the sampling frequency, the shorter the corresponding sampling step length, and the higher the test accuracy of the sensor. s Depends on the sampling frequency f of the ADC module ADC , f ADC Greater than f at the maximum motor speed s =N*f el .

[0178] S440. After sampling by ADC analog-to-digital conversion, the differential signal is calculated and expressed as follows:

[0179]

[0180] Where: ΔSin(n) and ΔCos(n) are both differential signals; n is the number of sampling times;.

[0181] S450. Calculate the rotor position angle and express it according to formula (13):

[0182]

[0183] S460. Compare the consistency between the signals Sin(n-1), Cos(n-1) and the differential signals ΔCos(n), ΔSin(n), expressed as formula (14):

[0184] abs(θest(n)-θout(n-1))<threshold (14)

[0185] Where: threshold is the differential consistency threshold.

[0186] It should be noted that the consistency can detect the nonlinearity of the sensor at each point. When the consistency exceeds the set threshold, the sensor enters the safety diagnosis mode.

[0187] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0188] The disclosed embodiments are described above to enable any person skilled in the art to implement or use the present invention. Various modifications of these embodiments are obvious to those skilled in the art, and the general principles defined herein may also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0189] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

[0190] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for controlling the angular position of a synchronous permanent magnet motor rotor, characterized in that: The angle position calibration system of the synchronous permanent magnet motor rotor is used; the angle position calibration system of the synchronous permanent magnet motor rotor includes a magnetoelectric eddy current sensor; the magnetoelectric eddy current sensor is used to provide a differential Sin+ output signal, a Sin- output signal, a Cos+ output signal, and a Cos- output signal; the magnetoelectric eddy current sensor includes a sensor and a signal wheel rotor; wherein: The signal wheel rotor is used to generate eddy current on its surface; the signal wheel rotor is made of conductive material; The sensor includes a PCB; the PCB includes a primary excitation current coil and a secondary coil; wherein: The secondary coil is used to receive the eddy current magnetic field; The primary excitation current coil is connected to a capacitor with a fixed capacitance value; the primary excitation current coil is excited by a high-frequency current signal generated by the integrated chip on the PCB to form a high-frequency oscillation circuit; the high-frequency oscillation circuit generates a changing magnetic field near the primary excitation current coil, which is mutually coupled with the secondary coil; The secondary coil comprises two sets of independent windings; the two sets of independent windings respectively generate a Sine output voltage signal and a Cosine output voltage signal with a phase shift of 90° electrical angle relative to each other; The two sets of independent windings are wound in Sine and Cosine waveform geometries; The Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal provided by the magnetoelectric eddy current sensor are further subjected to an optimization processing flow to obtain optimized differential forms of the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal; The optimization process sequentially includes a modulation and demodulation sub-process, an automatic gain control sub-process, and a high-voltage output protection sub-process; The optimized Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal are processed by the ECU to obtain a Sin_diff differential signal and a Cos_diff differential signal; The method for controlling the angular position of a synchronous permanent magnet motor rotor comprises the following steps: S100. Perform output signal voltage range detection; then perform the following operations based on the detection result: If the detection result of the output signal voltage range detection is that the output signal is within the manually preset normal voltage range, executing S200; If the detection result of the output signal voltage range detection is that the output signal is not within the normal voltage range, an abnormal signal alarm and a maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method is terminated; S200. Perform output signal common mode voltage detection; then perform the following operations according to the detection result: If the detection result of the output signal common mode voltage detection is that the common mode values ​​of the Sin+ output signal and the Sin- output signal after low-pass filtering meet the manually preset common mode value qualification condition, and the common mode values ​​of the Cos+ output signal and the Cos- output signal after low-pass filtering meet the common mode value qualification condition, execute S300; If the detection result of the output signal common mode voltage detection is that the common mode values ​​of the Sin+ output signal and the Sin- output signal after low-pass filtering do not meet the common mode value qualification condition, or the common mode values ​​of the Cos+ output signal and the Cos- output signal after low-pass filtering do not meet the common mode value qualification condition, then the signal abnormality alarm and the maintenance request alarm are issued; then the process of the synchronous permanent magnet motor rotor angle position control method is terminated; S300. Perform amplitude normalization detection; then perform the following operations based on the detection results: If the detection result of the amplitude normalization detection is that the amplitude meets the manually preset amplitude normalization qualification condition, executing S400; If the detection result of the amplitude normalization detection is that the amplitude does not meet the amplitude normalization qualification condition, the abnormal signal alarm and the maintenance request alarm are issued; then the process of the angle position control method of the synchronous permanent magnet motor rotor is terminated; The amplitude normalization qualification condition in S300 is expressed as follows: 1-error≤Sin 2 (θ)+Cos 2 (θ)≤1+error Where: error is the accuracy compensation, which is preset manually; θ is the position angle of the rotor; Sin(θ) is the output signal obtained after offset compensation and amplitude normalization of Sin+ or Sin-; Cos(θ) is the output signal obtained after offset compensation and amplitude normalization of Cos+ or Cos-; The Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal are expressed as follows: Where: Vps is the amplitude of the single-ended output signal Sin+ or Sin-; Vpc is the amplitude of the single-ended output signal Cos+ or Cos-; Vos is the bias voltage of the single-ended output signal Sin+ or Sin-; Voc is the bias voltage of the single-ended output signal Cos+ or Cos-; Sin(θ) and Cos(θ) are expressed as follows: Wherein: Sin_diff is the Sin_diff differential signal; Cos_diff is the Cos_diff differential signal; Sin_diff and Cos_diff are expressed as follows: Offset_Sin and offset_Cos are bias voltages, expressed as follows: Amplitude_Sin and Amplitude_Cos are the voltage amplitudes, expressed as follows: S400. Perform differential consistency detection; then perform the following operations based on the detection results: If the detection result of the differential consistency detection is that the differential consistency does not exceed the manually preset differential consistency threshold, a detection qualified signal is issued; and then the process of the angle position control method of the synchronous permanent magnet motor rotor is ended; If the detection result of the differential consistency detection is that the differential consistency exceeds the differential consistency threshold, the magnetoelectric eddy current sensor is placed in a safety diagnosis mode; The differential consistency detection in S400 specifically includes the following steps: S410. Obtaining the actual rotor mechanical speed and the number of motor pole pairs of the motor; S420. The electrical angle frequency of the motor rotor rotation is calculated based on the actual mechanical speed of the motor rotor and the number of motor pole pairs, and is expressed as follows: f el =rotor_speed*Npp / 60 Where: f el is the electrical angle frequency of the motor rotor rotation, in Hz; rotor_speed is the actual rotor mechanical speed of the motor, in rpm; Npp is the number of motor pole pairs, in s / min; S430. Set the sampling frequency; the sampling frequency is an integer multiple of the electrical angle frequency of the motor rotor rotation, expressed as follows: f s =N*f el Where: f s is the sampling frequency; N is a multiple; S440. After sampling through ADC analog-to-digital conversion, the differential signal is calculated and expressed as follows: Where: ΔSin(n) and ΔCos(n) are both differential signals; n is the number of sampling times; S450. Calculate the rotor position angle and express it as follows: S460. Compare the consistency between the signals Sin(n-1), Cos(n-1) and the differential signals ΔCos(n), ΔSin(n), expressed as follows: abs(θest(n)-θout(n-1))<threshold Wherein: threshold is the differential consistency threshold.

2. The method for controlling the angular position of a synchronous permanent magnet motor rotor according to claim 1, characterized in that: The output signal voltage range detection in S100 specifically includes the following steps: S110. Continuously collect the Sin+ output signal, the Sin- output signal, the Cos+ output signal, and the Cos- output signal; then obtain the maximum value and the minimum value of the output signal; S120. Detect the power supply voltage; then perform the following operations according to the value of the power supply voltage: If the power supply voltage is 5V, execute S130; If the power supply voltage is not 5V, return to and execute S110 again; S130. The ECU detects whether the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, performs the following operations: If the maximum value of the output signal obtained in S110 is between 0.25V and 4.75V, execute S140; If the maximum value of the output signal obtained in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range; S140. The ECU detects whether the minimum value of the output signal obtained in S110 is between 0.25V and 4.75V; then, according to the detection result, performs the following operations: If the minimum value of the output signal obtained in S110 is between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal being within the normal voltage range; If the minimum value of the output signal acquired in S110 is not between 0.25V and 4.75V, the detection result of the output signal voltage range detection is set as the output signal is not within the normal voltage range.

3. The method for controlling the angular position of a synchronous permanent magnet motor rotor according to claim 2, characterized in that: The common mode value of the Sin+ output signal and the Sin- output signal in S200 is expressed as follows: Sin_com=(Sin+)+(Sin-) Wherein: Sin_com is the common mode value of the Sin+ output signal and the Sin- output signal; Sin+ is the collected value of the Sin+ output signal; Sin- is the collected value of the Sin- output signal; The common mode value of the Cos+ output signal and the Cos- output signal in S200 is expressed as follows: Cos_com=(Cos+)+(Cos-) Wherein: Cos_com is the common mode value of the Cos+ output signal and the Cos- output signal; Cos+ is the collected value of the Cos+ output signal; Cos- is the collected value of the Cos- output signal; The common mode value qualification condition in S200 is expressed as follows: Wherein: Vcc is the power supply voltage; Sin_com_filtered is the common mode value of the Sin+ output signal and the Sin- output signal after low-pass filtering; Cos_com_filtered is the common mode value of the Cos+ output signal and the Cos- output signal after low-pass filtering.

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