Five-phase hybrid excitation motor rotor position detection method based on excitation winding high-frequency pulsating injection

Abstract

The invention discloses a five-phase hybrid excitation motor rotor position detection method based on excitation winding high-frequency pulsating injection, and the method comprises the steps: injecting a high-frequency pulsating voltage signal to an excitation winding, extracting a current signal containing rotor position information in a q axis of a third harmonic space, and inputting the current signal to a cascade phase-locked loop; the high-frequency carrier frequency is locked through the first-stage phase-locked loop, noise is filtered out, a pure high-frequency component is extracted, the high-frequency component is demodulated through the second-stage phase-locked loop, position error signals are extracted through low-pass filtering, proportional-integral control is combined, the rotor position and rotating speed information of the five-phase hybrid excitation motor is obtained, and operation without a position sensor is achieved. According to the excitation winding injection method provided by the invention, the influence of the salient pole effect of the rotor is fully considered, the characteristic of uniform distribution of an excitation magnetic field is utilized, and the position of the rotor can be accurately detected under the condition that the salient pole ratio of the rotor is low; moreover, the method is high in position detection precision, is high in anti-interference capability, is simple and convenient, and is easy to achieve.

Description

Technical Field

[0001] The present invention belongs to the technical field of five-phase motor control methods, and particularly relates to a rotor position detection method for a five-phase hybrid excitation motor based on high-frequency pulsating injection of an excitation winding. Background Technique

[0002] A five-phase hybrid excitation motor is a new type of multi-phase motor that combines two excitation methods of permanent magnet excitation and electric excitation. Due to the characteristics of high torque / power density, large torque capacity, wide speed regulation range, low torque ripple, and strong fault tolerance ability of this kind of motor, it is very suitable for electric vehicle drive motors. The key to the control of a five-phase hybrid excitation motor lies in the accurate detection of the real-time angular displacement and mechanical speed of the rotor. Therefore, position sensors such as magnetic encoders, optical encoders, resolvers, and Hall sensors are required, which will increase the volume, weight, and overall cost of the drive system and reduce the reliability of the system. The use of sensorless technology can effectively solve the above problems. Therefore, the sensorless technology of five-phase hybrid excitation motors has broad application requirements and far-reaching research significance.

[0003] The present invention proposes a rotor position detection method for a five-phase hybrid excitation motor based on high-frequency pulsating injection of an excitation winding, improves the accuracy and reliability during operation, and promotes the application of such motors in the field of electric vehicles. Summary of the Invention

[0004] The purpose of the present invention is to provide a rotor position detection method for a five-phase hybrid excitation motor based on high-frequency pulsating injection of an excitation winding, and solve the problem that the existing five-phase hybrid excitation motor relies on multiple sensors for real-time detection of the rotor, resulting in a relatively large volume of the system.

[0005] The technical solution adopted by the present invention is: a rotor position detection method for a five-phase hybrid excitation motor based on high-frequency pulsating injection of an excitation winding. By injecting a high-frequency pulsating voltage signal into the excitation winding, a current signal containing rotor position information is extracted on the q-axis of the third harmonic space and input into a cascaded phase-locked loop; the first-level phase-locked loop locks the high-frequency pulsating frequency, filters out noise and extracts a pure high-frequency component, and then the second-level phase-locked loop demodulates and low-pass filters the high-frequency component to extract a position error signal. Combining proportional-integral control, the rotor position and speed information of the five-phase hybrid excitation motor are obtained to achieve sensorless operation. The specific operation steps are as follows:

[0006] Step 1: Establish a mathematical model of the five-phase hybrid excitation motor to obtain a voltage-current relationship matrix of the five-phase hybrid excitation motor.

[0007] Step 2: Establish a relationship matrix between the high-frequency voltage and high-frequency response current of the five-phase hybrid excitation motor in a virtual two-phase rotating coordinate system.

[0008] Step 3: Inject a high-frequency pulsating voltage signal into the excitation winding when the motor runs at a low speed, and collect the phase currents \(i\) A , \(i\) B , \(i\) C , \(i\) D , \(i\) E and the excitation current \(i\) f from the main circuit and the excitation circuit of the motor respectively; Perform Park transformation and virtual transformation on the collected phase currents \(i\) A , \(i\) B , \(i\) C , \(i\) D , \(i\) E to obtain the d-axis armature current and and the q-axis armature current and in the virtual two-phase rotating coordinate system;

[0009] Step 4: Input the current in Step 3 into the first-stage phase-locked loop to lock the frequency of the high-frequency pulsating voltage signal and obtain the high-frequency response current ;

[0010] Step 5: Demodulate the high-frequency response current obtained in Step 4, then filter out the high-frequency components in the demodulated signal through a low-pass filter to obtain a signal containing rotor position estimation error information, and use the second-stage phase-locked loop to process it to obtain the rotor position estimation value, and differentiate the rotor position estimation value to obtain the rotor estimated speed.

[0011] The characteristics of the present invention also lie in that

[0012] The mathematical model and voltage equation of the five-phase hybrid excitation motor described in Step 1 are:

[0013] The mathematical model of the five-phase hybrid excitation motor in the d-q reference coordinate system is:

[0014] Flux linkage equation:

[0015]

[0016] Voltage equation:

[0017]

[0018] Among them, the subscripts "1" and "3" respectively represent the fundamental wave space and the third harmonic space components, \(\psi\) d1 , \(\psi\) d3 are the stator d-axis flux linkages, \(\psi\) q1 , \(\psi\) q3 are the stator q-axis flux linkages, \(\psi\) m1 , \(\psi\)m3 is the amplitude of the permanent magnet flux linkage; L d1 , L d3 is the d-axis inductance, L q1 , L q3 is the q-axis inductance, L f is the inductance of the field winding, M f1 , M f3 is the mutual inductance between the armature and the field winding; i d1 , i d3 is the d-axis current, i q1 , i q3 is the q-axis current, i f is the current of the field winding, ω e is the electrical angular velocity; u d1 , u d3 is the d-axis voltage, u q1 , u q3 is the q-axis voltage, u f is the voltage of the field winding, and R is the resistance of the armature winding.

[0019] Under the condition of high-frequency pulsating signal injection, the reactance value of the motor winding is much larger than the impedance value. Ignoring the influence of the resistance voltage drop, the d-q axis cross-coupling term, and the back electromotive force on the winding terminal voltage, the voltage equation is rewritten as:

[0020]

[0021] From the voltage equation, the current expression in the actual two-phase rotating coordinate system can be obtained as:

[0022]

[0023] In the formula: is the differential form of the currents i d1 , i q1 , i d3 , i q3 .

[0024]

[0025] Step 2 High-frequency current response expression in the virtual two-phase rotating coordinate system:

[0026]

[0027] Among them is the d-q axis high-frequency current response in the fundamental wave space of the virtual two-phase rotating coordinate system, is the d-q axis high-frequency current response in the third harmonic space of the virtual two-phase rotating coordinate system, is the high-frequency current response of the field winding, are the d-q axis high-frequency voltage components in the fundamental wave space under the virtual two-phase rotating coordinate system, are the d-q axis high-frequency voltage components in the third harmonic space under the virtual two-phase rotating coordinate system, is the high-frequency voltage component of the exciting winding;

[0028] In the formula:

[0029]

[0030]

[0031] Among them, M fh1 and M fh3 are the high-frequency mutual inductances in the fundamental wave space and the third harmonic space between the armature and the exciting winding; L dh1 and L dh3 are the high-frequency reactances of the fundamental wave and the third harmonic on the d axis; L fh is the high-frequency reactance of the exciting winding; Δθ e is the phase difference between the d axis and the q axis in the actual and virtual cases.

[0032] The high-frequency pulsating voltage signal injected in Step 3 is:

[0033]

[0034] Among them, U mh is the amplitude of the high-frequency pulsating voltage signal, ω h is the angular velocity of the high-frequency pulsating voltage signal; u ind1 and u ind3 are the d-axis voltage signals u inq1 and u inq3 are the q-axis voltage signals; u inf is the exciting voltage signal.

[0035] Step 4 is specifically as follows:

[0036] The first-stage phase-locked loop phase detector multiplies the virtual q-axis armature current by the oscillation signal output by the first-stage phase-locked loop voltage-controlled oscillator:

[0037]

[0038] Among them, Δe is the instantaneous phase error of the phase detector comparing the q-axis armature current with the internal oscillation signal , is the estimated high-frequency frequency output by the first-stage phase-locked loop voltage-controlled oscillator. When the phase-locked loop is locked, is equal to the frequency ω h of the injected high-frequency pulsating voltage signal;

[0039] Generate an error voltage e for driving a voltage-controlled oscillator through a loop filter fil :

[0040]

[0041] where n is the current signal and n - 1 is the previously acquired signal; K p1 、K i1 are the proportional-integral coefficients of the first-stage phase-locked loop respectively;

[0042] Finally, complete frequency locking by outputting an estimated high-frequency frequency through the voltage-controlled oscillator:

[0043]

[0044] where ω h0 is the initial frequency of the phase detector, and K vco1 is the gain coefficient determining the frequency adjustment sensitivity;

[0045] Step 5 is specifically as follows:

[0046] Demodulate the high-frequency response current using the estimated high-frequency frequency output in Step 4 to obtain the high-frequency response current as given by Equation (9):

[0047]

[0048] At this time, the high-frequency response current of the third-harmonic space q-axis is:

[0049]

[0050] Also:

[0051]

[0052] where I fh is the amplitude of the high-frequency response current;

[0053] Then, from Equation (6), Equation (11), and Equation (12), the demodulated high-frequency response current i qh3-l is obtained as:[[ID=si]]

[0054]

[0055] where is the amplitude of the high-frequency response current;

[0056] Use a low-pass filter to filter out the second-harmonic component in i qh3-l and retain the low-frequency error signal:

[0057]

[0058] Input the error signal output from the low-pass filter into the second-stage phase-locked loop, and obtain the estimated rotor position by adjusting the proportional-integral parameters and the estimated rotor speed

[0059] The beneficial effects of the present invention are as follows:

[0060] (1) The sensorless technology adopted by the present invention effectively reduces the cost, volume and weight of the motor, and improves the applicability of the motor in more application backgrounds.

[0061] (2) The present invention fully considers the influence of salient polarity. By injecting a high-frequency pulsating voltage signal into the excitation winding, the characteristics that the magnetic flux generated by the excitation winding current is coupled with the d-axis magnetic flux and not coupled with the q-axis magnetic flux are used to obtain the rotor position and speed information, which has the characteristic of reducing the influence of rotor salient polarity.

[0062] (3) The present invention adopts the method of extracting the response signal in the third-harmonic space q-axis. The advantage of this method is that the third-harmonic space is less affected by the interference sources near the fundamental frequency, and the anti-interference ability of obtaining the rotor position and speed can be improved.

[0063] (4) The signal in the third-harmonic space is insensitive to the changes of motor parameters (such as resistance, inductance, etc.), and can better overcome the influence of motor parameter changes on position estimation.

[0064] (5) Extracting the response signal through the cascaded phase-locked loop has the advantages of wide frequency adaptability, simpler hardware implementation and being able to adapt to harsh electromagnetic environments.

[0065] (6) The method of the present invention is applicable to both surface-mounted and interior-mounted five-phase hybrid-excitation motors at the same time. Description of the Drawings

[0066] Figure 1 is the flowchart of the rotor position detection method for a five-phase hybrid-excitation motor based on high-frequency pulsating injection into the excitation winding according to the present invention.

[0067] Figure 2 is the block diagram of the part for processing the current signal containing rotor position information and obtaining the estimated rotor position and estimated speed in the method of the present invention.

[0068] Figure 3 is the waveform diagram of the estimated rotor position, the actual rotor position and the rotor position error in Embodiment 6 of the present invention.

[0069] Figure 4 is the waveform diagram of the actual rotor speed and the speed error in Embodiment 6 of the present invention. Detailed Embodiments

[0070] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0071] Embodiment 1

[0072] The rotor position detection method of a five-phase hybrid excitation motor based on high-frequency pulsating injection into the excitation winding of the present invention injects a high-frequency pulsating voltage signal into the excitation winding, extracts the current signal containing rotor position information in the third harmonic space q-axis, and inputs it into a cascaded phase-locked loop; the first-level phase-locked loop locks the high-frequency pulsating frequency, filters out noise and extracts the pure high-frequency component, and then the second-level phase-locked loop demodulates and low-pass filters the high-frequency component to extract the position error signal. Combining proportional-integral control, the rotor position and speed information of the five-phase hybrid excitation motor are obtained to achieve sensorless operation.

[0073] Embodiment 2

[0074] The rotor position detection method of a five-phase hybrid excitation motor based on high-frequency pulsating injection into the excitation winding of the present invention has the following specific operation steps:

[0075] Step 1: Establish the mathematical model of the five-phase hybrid excitation motor to obtain the voltage-current relationship matrix of the five-phase hybrid excitation motor;

[0076] Step 2: Establish the relationship matrix between the high-frequency voltage and the high-frequency response current of the five-phase hybrid excitation motor in the virtual two-phase rotating coordinate system;

[0077] Step 3: When the motor is running at low speed, inject a high-frequency pulsating voltage signal into the excitation winding, and collect the phase currents i A , i B , i C , i D , i E and the excitation current i f from the main circuit and the excitation circuit of the motor respectively; perform Park transformation and virtual transformation on the collected phase currents i A , i B , i C , i D , i E to obtain the d-axis armature current and and the q-axis armature current and

[0078] Step 4: Input the current in Step 3 into the first-level phase-locked loop to lock the high-frequency pulsating voltage signal frequency and obtain the high-frequency response current

[0079] Step 5: The high-frequency response current obtained in Step 4 is demodulated, and then the high-frequency components in the demodulated signal are filtered out through a low-pass filter to obtain a signal containing rotor position estimation error information. The rotor position estimation value is obtained by processing with a second-order phase-locked loop, and the differential of the rotor position estimation value is taken to obtain the rotor estimated speed.

[0080] Embodiment 3

[0081] Based on Embodiment 2, the mathematical model and voltage equation of the five-phase hybrid excitation motor in Step 1 are as follows:

[0082] The mathematical model of the five-phase hybrid excitation motor in the d-q reference coordinate system is:

[0083] Flux linkage equation:

[0084]

[0085] Voltage equation:

[0086]

[0087] Among them, the subscripts "1" and "3" respectively represent the fundamental wave space and the third harmonic space components, ψ d1 , ψ d3 are the stator d-axis flux linkages, ψ q1 , ψ q3 are the stator q-axis flux linkages, ψ m1 , ψ m3 are the permanent magnet flux linkage amplitudes; L d1 , L d3 are the d-axis inductances, L q1 , L q3 are the q-axis inductances, L f is the field winding inductance, M f1 , M f3 are the mutual inductances between the armature and the field winding; i d1 , i d3 are the d-axis currents, i q1 , i q3 are the q-axis currents, i f is the field winding current, ω e is the electrical angular velocity; u d1 , u d3 are the d-axis voltages, u q1 , u q3 are the q-axis voltages, u f is the field winding voltage, and R is the armature winding resistance.

[0088] Under the condition of high-frequency pulsating signal injection, the inductive reactance value of the motor winding is much larger than the impedance value. Ignoring the influence of the resistance voltage drop, the d-q axis cross-coupling term, and the back electromotive force on the winding terminal voltage, the voltage equation is rewritten as:

[0089]

[0090] The current expression in the actual two-phase rotating coordinate system can be obtained from the voltage equation as:

[0091]

[0092] In the formula:

[0093]

[0094] Example 4

[0095] Based on Example 3, the voltage equation expression under high-frequency pulsating voltage is:

[0096]

[0097] The expression of the high-frequency current response related to the high-frequency voltage in the actual two-phase rotating coordinate system can be obtained from the high-frequency pulsating voltage equation as:

[0098]

[0099] In the formula:

[0100]

[0101]

[0102] Let the phase difference between the actual two-phase rotating coordinate system and the virtual two-phase rotating coordinate system be Δθ e , and the transformation matrix from the actual two-phase rotating coordinate system to the virtual rotating coordinate system is:

[0103]

[0104] The transformation matrix from the virtual two-phase rotating coordinate system to the actual rotating coordinate system is:

[0105]

[0106] The expression of the high-frequency current response in the virtual two-phase rotating coordinate system can be obtained:

[0107]

[0108] Among them is the d-q axis high-frequency current response in the fundamental wave space under the virtual two-phase rotating coordinate system, For the high-frequency current responses of the d-q axes in the third-harmonic space under the virtual two-phase rotating coordinate system, For the high-frequency current response of the exciting winding, For the high-frequency voltage components of the d-q axes in the fundamental-wave space under the virtual two-phase rotating coordinate system, For the high-frequency voltage components of the d-q axes in the third-harmonic space under the virtual two-phase rotating coordinate system, For the high-frequency voltage component of the exciting winding; where:

[0109]

[0110]

[0111] Example 5

[0112] Based on Example 4, Step 3 is specifically as follows:

[0113] The injected high-frequency pulsating voltage signal is:

[0114]

[0115] Where, U mh is the amplitude of the high-frequency pulsating voltage signal, ω h is the angular velocity of the high-frequency pulsating voltage signal. u ind1 , u ind3 are the d-axis voltage signals u inq1 , u inq3 are the q-axis voltage signals; u inf is the exciting voltage signal. Compare the exciting current reference value with the actual negative feedback, input the compared value into a PI regulator for adjustment, then inject the high-frequency pulsating voltage signal, and finally input it into PWM.

[0116] Example 6

[0117] Based on Example 5, the flowchart of the rotor position detection method for a five-phase hybrid-excitation motor based on high-frequency pulsating injection into the exciting winding is as shown in Figure 1 and is implemented according to the following steps:

[0118] Step 1: Deduce the motor model of the five-phase hybrid-excitation motor to obtain the voltage-current relationship matrix of the five-phase hybrid-excitation motor;

[0119] Step 2: Deduce the relationship matrix between the high-frequency pulsating injection signal and the high-frequency current response of the five-phase hybrid-excitation motor under the virtual two-phase rotating coordinate system, specifically:

[0120] Step 3: Inject a high-frequency pulsating signal into the exciting winding when the motor is running at low speed, and collect the phase currents i A , i B , i C, i D , i E and the exciting current i f ; The collected phase currents i A , i B , i C , i D , i E are subjected to Park transformation and coordinate axis transformation to obtain the d-axis armature winding current and and the q-axis current and

[0121] Step 4: Input the current in Step 3 into the first-level phase-locked loop. By multiplying with the internal oscillation signal and filtering through the loop filter, lock the high-frequency carrier frequency to obtain the required demodulation signal; as Figure 3 shown, specifically:

[0122] Multiply the collected with the output by the VCO of the first-level phase-locked loop:

[0123]

[0124] where Δe is the instantaneous phase error between and the oscillation signal, and is the estimated high-frequency frequency output by the first-level phase-locked loop. When the phase-locked loop is locked, is equal to the high-frequency pulsating frequency .

[0125] Generate the error voltage e fil for driving VOC through the loop filter:

[0126] e fil [n] = e fil [n - 1] + K p1 (e pd [n] - e pd [n - 1]) + K i1 e pd [n] (8)

[0127] Finally, complete the frequency locking by outputting the estimated high-frequency frequency through VOC:

[0128]

[0129] where ω h0 is the initial frequency of the phase discriminator, and K vco1 is the gain coefficient determining the frequency adjustment sensitivity.

[0130] Step 5: As Figure 2 shown, demodulate the high-frequency response current obtained in Step 4, and then filter out the high-frequency components in the modulation signal through a low-pass filter to obtain a signal containing rotor position estimation error information. Use the second-stage phase-locked loop to process it to obtain the rotor position estimation value, and differentiate the rotor position estimation value to obtain the rotor estimated speed. Specifically:

[0131] Demodulate the high-frequency response current through the pure carrier obtained in Step 4 for the high-frequency response current The high-frequency response current can be obtained from Equation (9) as:

[0132]

[0133] After injecting high frequency into the excitation winding, the high-frequency response current of the third harmonic space q-axis is:

[0134]

[0135] Also:

[0136]

[0137] where I fh is the amplitude of the high-frequency response current.

[0138] Then, from Equation (10), Equation (11) and Equation (12), the demodulated high-frequency response current i qh3-l is:

[0139]

[0140] where is the amplitude of the high-frequency response current.

[0141] Use a low-pass filter to filter out the second harmonic component in i qh3-l and retain the low-frequency error signal:

[0142]

[0143] Input the error signal output by the low-pass filter into the second-stage phase-locked loop, and obtain the rotor estimated position and the rotor estimated speed

[0144] The rotor estimated position and the rotor estimated speed are calculated as follows:

[0145]

[0146] where ω is the estimated rotational speed at the previous moment, Δθ is the correction amount of the position error, Δθ is generated by a PI regulator, and Δθ = K p2 μ + K i2 ∫μdt, where K p2 , K i2 is the proportional-integral coefficient of the second-stage phase-locked loop;

[0147] Differentiating gives the estimated rotational speed :

[0148] Figure 3 is the waveform diagram of the estimated rotor position, the actual rotor position, and the rotor position error obtained by using the detection method of the present invention when the motor is at 100 r / min and a load of 0.5 N·m is suddenly applied. It can be seen that the estimation value in the proposed method tracks the actual value very well, and the position identification of the five-phase hybrid-excitation motor can be achieved.

[0149] Figure 4 is the waveform diagram of the actual rotor speed and the rotational speed error obtained by using the detection method of the present invention when the motor is at 100 r / min and a load of 0.5 N·m is suddenly applied. It can be seen that the estimated rotational speed in the proposed method can track the actual rotational speed very well.

[0150] The above are only some implementation schemes of the present invention. For those skilled in the art, without departing from the principle of the present invention, several improvements and refinements made to the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A rotor position detection method for a five-phase hybrid excitation motor based on high-frequency pulsating injection into the excitation winding, characterized in that, By injecting a high-frequency pulsating voltage signal into the excitation winding, a current signal containing rotor position information is extracted on the q-axis of the third harmonic space and input into the cascaded phase-locked loop. The first-stage phase-locked loop locks the high-frequency pulsating frequency, filters out the noise and extracts the pure high-frequency component. Then, the second-stage phase-locked loop demodulates and low-pass filters the high-frequency component to extract the position error signal. Combining proportional-integral control, the rotor position and speed information of the five-phase hybrid-excitation motor are obtained, realizing sensorless operation.

2. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 1, wherein The specific operation steps are as follows: Step 1: Establish a mathematical model of the five-phase hybrid-excitation motor to obtain the voltage-current relationship matrix of the five-phase hybrid-excitation motor; Step 2: Establish the relationship matrix between the high-frequency voltage and high-frequency response current of the five-phase hybrid-excitation motor in the virtual two-phase rotating coordinate system; Step 3: Inject a high-frequency pulsating voltage signal into the excitation winding when the motor is running at a low speed, and collect the phase currents \(i\) A , \(i\) B , \(i\) C , \(i\) D , \(i\) E and the excitation current \(i\) f ; Perform Park transformation and virtual transformation on the collected phase currents \(i\) A , \(i\) B , \(i\) C , \(i\) D , \(i\) E to obtain the d-axis armature current and and the q-axis armature current and Step 4: Input the current in Step 3 into the first-stage phase-locked loop to lock the frequency of the high-frequency pulsating voltage signal to obtain the high-frequency response current Step 5: Demodulate the high-frequency response current obtained in Step 4, and then filter out the high-frequency components in the demodulated signal through a low-pass filter to obtain a signal containing the rotor position estimation error information. Use the second-level phase-locked loop to process to obtain the rotor position estimation value, and differentiate the rotor position estimation value to obtain the rotor estimated speed. ​ 3. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 1, characterized in that The mathematical model and voltage equation of the five-phase hybrid-excitation motor described in Step 1 are: The mathematical model of the five-phase hybrid-excitation motor in the d-q reference coordinate system is: Flux linkage equation: Voltage equation: where the subscripts "1" and "3" represent the fundamental wave space and third harmonic space components respectively, ψ d1 and ψ d3 are the stator d-axis flux linkages, ψ q1 and ψ q3 are the stator q-axis flux linkages, ψ m1 and ψ m3 are the permanent magnet flux linkage amplitudes; L d1 and L d3 are the d-axis inductances, L q1 and L q3 are the q-axis inductances, L f is the field winding inductance, M f1 and M f3 are the mutual inductances between the armature and the field winding; i d1 and i d3 are the d-axis currents, i q1 and i q3 are the q-axis currents, i f is the field winding current, ω e is the electrical angular velocity; u d1 and u d3 are the d-axis voltages, u q1 and u q3 are the q-axis voltages, u f is the field winding voltage, and R is the armature winding resistance.

4. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 3, characterized in that, Under the condition of high-frequency pulsating signal injection, the inductive reactance value of the motor winding is much larger than the impedance value. Ignoring the influence of the resistance voltage drop, the d-q axis cross-coupling term, and the back electromotive force on the winding terminal voltage, the voltage equation is rewritten as: The current expression in the actual two-phase rotating coordinate system can be obtained from the voltage equation as: Where:

5. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 4, characterized in that The high-frequency current response expression in the virtual two-phase rotating coordinate system in Step 2: wherein is the d-q axis high-frequency current response in the fundamental wave space under the virtual two-phase rotating coordinate system, is the d-q axis high-frequency current response in the third harmonic space under the virtual two-phase rotating coordinate system, is the high-frequency current response of the exciting winding, is the d-q axis high-frequency voltage component in the fundamental wave space under the virtual two-phase rotating coordinate system, is the d-q axis high-frequency voltage component in the third harmonic space under the virtual two-phase rotating coordinate system, is the high-frequency voltage component of the exciting winding; Where: Among them, M fh1 and M fh3 are the high-frequency mutual inductances in the fundamental wave space and the third harmonic space between the armature and the field winding; L dh1 and L dh3 are the high-frequency reactances of the fundamental wave and the third harmonic on the d-axis; L fh is the high-frequency reactance of the field winding; Δθ e is the phase difference between the d-axis and the q-axis in the actual and virtual cases.

6. The rotor position detection method of the five-phase hybrid-excitation motor based on high-frequency pulsating injection into the excitation winding according to claim 5, characterized in that The injected high-frequency pulsating voltage signal in Step 3 is: Among them, U mh is the amplitude of the high-frequency pulsating voltage signal, and ω h is the angular velocity of the high-frequency pulsating voltage signal; u ind1 , u ind3 are the d-axis voltage signals u inq1 , u inq3 are the q-axis voltage signals; u inf is the excitation voltage signal.

7. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 6, characterized in that, Step 4 is as follows: The first-level phase-locked loop phase detector multiplies the virtual q-axis armature current by the oscillation signal output by the first-level phase-locked loop voltage-controlled oscillator : Among them, Δe is the instantaneous phase error between the q-axis armature current compared by the phase discriminator through the multiplier and the internal oscillation signal , is the estimated high-frequency frequency output by the voltage-controlled oscillator of the first-stage phase-locked loop. When the phase-locked loop is locked is equal to the frequency ω h of the injected high-frequency pulsating voltage signal; Generate an error voltage e for driving a voltage-controlled oscillator through a loop filter fil : e fil [n] = e fil [n - 1]+K p1 (Δe[n]-Δe[n - 1])+K i1 Δe[n] (8) where n is the current signal and n-1 is the previously acquired signal; K p1 and K i1 are the proportional-integral coefficients of the first-order phase-locked loop, respectively; Finally, the estimated high-frequency frequency is output by the voltage-controlled oscillator to complete frequency locking: where ω h0 is the initial frequency of the phase detector, and K vco1 is the gain coefficient that determines the frequency adjustment sensitivity.

8. The rotor position detection method of the five-phase hybrid excitation motor based on high-frequency pulsating injection of the excitation winding according to claim 7, characterized in that Step 5 is as follows: Through the estimated high-frequency frequency output in step 4 For the high-frequency response current Demodulation is performed. From formula (9), the high-frequency response current can be obtained as follows: At this time, the high-frequency response current on the q-axis of the third harmonic space is: Also: Among them, I fh is the amplitude of the high-frequency response current; Then, from Equation (6), Equation (11), and Equation (12), the demodulated high-frequency response current i can be obtained qh3＝l : Among them, is the high-frequency response current amplitude; Use a low-pass filter to filter out the second harmonic component in i qh3＝l and retain the low-frequency error signal: The error signal output by the low-pass filter is input into the second-stage phase-locked loop, and the estimated rotor position is obtained by adjusting the proportional-integral parameters and the estimated rotor speed

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