A fault-tolerant control method for permanent magnet synchronous motor based on short-circuit current suppression
By acquiring phase current in a permanent magnet synchronous motor for coordinate transformation and closed-loop control, the inter-turn short-circuit current is identified and suppressed, thus solving the current disturbance problem of the permanent magnet synchronous motor under fault conditions. This enables continuous operation and fault-tolerant control of the motor, making it suitable for high-reliability applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGNAN UNIV
- Filing Date
- 2026-04-13
- Publication Date
- 2026-07-14
AI Technical Summary
Permanent magnet synchronous motors are prone to inter-turn short circuit faults during operation, which can lead to excessive short circuit current, causing winding overheating, permanent magnet demagnetization, and even system shutdown. Existing technologies are difficult to effectively suppress short circuit current and have insufficient adaptability.
By collecting the phase current of the permanent magnet synchronous motor and performing coordinate transformation, the quadrature axis current component is extracted, the current fault characteristic variables are reconstructed, and the short-circuit current is suppressed by closed-loop control. The inter-turn short-circuit characteristic harmonics are identified by fast Fourier transform, and the current reference value is corrected to achieve fault-tolerant control.
It effectively suppresses current disturbances caused by inter-turn short circuit faults, maintains continuous motor operation, improves fault tolerance, and is suitable for high-reliability applications such as electric vehicles and ship propulsion. It is also compatible with three-phase and five-phase motors.
Smart Images
Figure CN122394472A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of permanent magnet synchronous motors, and in particular to a fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression. Background Technology
[0002] Permanent magnet synchronous motors (PMSMs) are widely used in applications with extremely high reliability requirements, such as electric vehicles, ship propulsion, and aerospace, due to their advantages of high torque, high power density, and high efficiency. However, PMSMs are prone to various types of faults during operation, with short-circuit faults and open-circuit faults being the most common. Inter-turn short circuits in the stator windings are one of the most frequent types of faults. When this occurs, a short-circuit current with an amplitude far exceeding the rated current is generated, causing winding overheating, demagnetization of the permanent magnets, and even system shutdown, seriously threatening the safe operation of the equipment.
[0003] Currently, stator inter-turn short-circuit fault suppression technologies are mainly divided into motor design methods and control-based strategies. Motor design methods focus on hardware improvements, enhancing the inherent reliability of the motor through topology optimization and fault-tolerant design. However, they are costly, lack versatility, and are difficult to adapt to motors already in use. Control-based strategies do not require significant hardware modifications and are widely used. Phase terminal short-circuiting is a common method, but it sacrifices the torque contribution of the faulty phase winding, leading to a decrease in motor output torque. Furthermore, this method requires electrical isolation at the hardware level, increasing system complexity and cost. Summary of the Invention
[0004] This application addresses the aforementioned problems and technical requirements by proposing a fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression. The technical solution of this application is as follows:
[0005] A fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression, comprising: The phase current of the permanent magnet synchronous motor is collected and coordinate transformation is performed to obtain the quadrature-axis current component in the fundamental plane. ; Based on the quadrature axis current component The amplitude and phase information of the current fault characteristic variables of the fault phase when an inter-turn short circuit occurs in a permanent magnet synchronous motor are extracted and combined with the real-time electrical angle of the permanent magnet synchronous motor. Reconstruction yields current fault characteristic variables ; Current fault characteristic variables Follow the expected amplitude of fault characteristic variables To achieve closed-loop fault-tolerant control of the permanent magnet synchronous motor.
[0006] Its further technical solution is: current fault characteristic variables , It is the proportion of the number of turns of the faulty phase that are short-circuited to the total number of turns in the phase winding of a permanent magnet synchronous motor. It is the short-circuit current flowing through the short-circuit resistance of the faulty phase.
[0007] A further technical solution is to base it on the quadrature axis current component. The amplitude and phase information of the characteristic variables of current faults includes: Regarding the quadrature axis current component A Fast Fourier Transform (FFT) is performed. If the FFT result contains a characteristic harmonic of inter-turn short circuit at a predetermined frequency, it is determined that the permanent magnet synchronous motor has an inter-turn short circuit fault, and the amplitude and phase information of the current fault characteristic variable is determined based on the amplitude and phase information of the inter-turn short circuit characteristic harmonic. If the FFT result does not contain a characteristic harmonic of inter-turn short circuit at a predetermined frequency, it is determined that the permanent magnet synchronous motor does not have an inter-turn short circuit fault.
[0008] The further technical solution is that the inter-turn short-circuit characteristic harmonic is a second harmonic with a frequency twice that of the motor's electrical frequency.
[0009] A further technical solution involves determining the amplitude and phase information of current fault characteristic variables based on the amplitude and phase information of the inter-turn short-circuit characteristic harmonics, including: Determine the amplitude of characteristic variables of current faults And determine the phase of the characteristic variables of the current fault. ;in, It is the amplitude of the characteristic harmonics of the inter-turn short circuit with a predetermined frequency. It is the phase of the inter-turn short-circuit characteristic harmonic with a predetermined frequency. It refers to the number of phase windings in a permanent magnet synchronous motor.
[0010] A further technical solution involves reconstructing the current fault characteristic variables. , It is based on the quadrature axis current component The amplitude of the extracted current fault characteristic variables, It is based on the quadrature axis current component The phase of the extracted current fault characteristic variables.
[0011] Its further technical solution is to use current fault characteristic variables Follow the expected amplitude of fault characteristic variables Closed-loop fault-tolerant control of permanent magnet synchronous motors for the target purpose includes: Calculate the expected amplitude of fault characteristic variables With current fault characteristic variables The difference between them yields the error signal. ; Using error signals Corrected direct-axis current reference value in the fundamental plane The corrected direct-axis current reference value is obtained. ; Based on the cross-axis current reference value and the corrected direct-axis current reference value The motor control signal is obtained to perform closed-loop fault-tolerant control on the permanent magnet synchronous motor.
[0012] A further technical solution is to utilize error signals. Corrected direct-axis current reference value in the fundamental plane The corrected direct-axis current reference value is obtained. include: Error signal The input to the PI controller obtains the direct-axis current control quantity in the fundamental plane. ; Direct-axis current control quantity Compared with direct-axis current reference value The corrected direct-axis current reference value is obtained by superposition. .
[0013] A further technical solution is to use the quadrature axis current reference value. and the corrected direct-axis current reference value Obtaining motor control signals for controlling permanent magnet synchronous motors includes: The direct-axis current prediction value is obtained based on the phase current of the permanent magnet synchronous motor using a current model. and cross-axis current prediction value ; Using the value function to minimize and Determine the motor control signal for the target.
[0014] The further technical solution is that the permanent magnet synchronous motor targeted by the method is a three-phase permanent magnet synchronous motor or a five-phase permanent magnet synchronous motor.
[0015] The beneficial technical effects of this application are: This application discloses a fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression. This method obtains the quadrature-axis current component of the fundamental plane by real-time acquisition of the motor phase current and coordinate transformation. The quadrature-axis current component is then reconstructed to obtain a current fault characteristic variable characterizing the short-circuit current. This current fault characteristic variable is used as feedback, and the expected amplitude of the fault characteristic variable is used as a setpoint to form a closed-loop regulation, outputting the motor control signal for the permanent magnet synchronous motor. This method can achieve accurate reconstruction of the fault characteristic variable and rapid closed-loop suppression of the short-circuit current. While achieving speed control, it effectively suppresses the current disturbance caused by inter-turn short-circuit faults, effectively reducing the overcurrent hazards caused by inter-turn short circuits in permanent magnet synchronous motors and improving the fault-tolerant operation capability of permanent magnet synchronous motors.
[0016] This method can suppress inter-turn short-circuit current without cutting off the motor power supply, enabling the permanent magnet synchronous motor to continue running even in fault conditions. It effectively avoids losses caused by motor shutdown and is particularly suitable for fields with extremely high reliability requirements, such as electric vehicles and ship propulsion.
[0017] This method does not rely on the redundancy characteristics of motors with a specific number of phases. Based solely on harmonic analysis and closed-loop control of the quadrature axis current component in the fundamental plane, it can simultaneously adapt to three-phase and five-phase permanent magnet synchronous motors, solving the problem of insufficient adaptability of existing technologies and expanding its application range. Attached Figure Description
[0018] Figure 1 It is the short-circuit circuit when an inter-turn short circuit occurs in phase A of a permanent magnet synchronous motor.
[0019] Figure 2 This is a control block diagram of a fault-tolerant control method for a permanent magnet synchronous motor in one embodiment of this application.
[0020] Figure 3 In one embodiment of this application, based on the quadrature axis current component Reconstruction yields current fault characteristic variables A schematic diagram.
[0021] Figure 4 Torque, speed, and quadrature-axis current components in a simulation example The current waveform diagram.
[0022] Figure 5 yes Figure 4 A waveform diagram comparing the reconstructed values and the true values of the current fault characteristic variables in a simulation example.
[0023] Figure 6 yes Figure 4 In the simulation example, the current fault characteristic variables of the permanent magnet synchronous motor are controlled according to the method of this application. The waveform diagram.
[0024] Figure 7 This is another simulation example involving torque, speed, and quadrature-axis current components. The current waveform diagram.
[0025] Figure 8 yes Figure 7 A waveform diagram comparing the reconstructed values and the true values of the current fault characteristic variables in a simulation example.
[0026] Figure 9 yes Figure 7 In the simulation example, the current fault characteristic variables of the permanent magnet synchronous motor are controlled according to the method of this application. The waveform diagram. Detailed Implementation
[0027] The specific embodiments of this application will be further described below with reference to the accompanying drawings.
[0028] This application discloses a fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression. This method, by suppressing short-circuit current, can simultaneously reduce torque ripple, lower copper losses, and improve the operating efficiency of the permanent magnet synchronous motor. This application first analyzes the situation when an inter-turn short-circuit fault occurs in the permanent magnet synchronous motor: When a permanent magnet synchronous motor experiences an inter-turn short circuit fault, the short-circuit resistance... This will short-circuit part of the winding in the faulty phase. Taking phase A winding of a permanent magnet synchronous motor as the faulty phase as an example, the faulty phase in the permanent magnet synchronous motor that experiences an inter-turn short circuit will exhibit... Figure 1 In the short-circuit loop, the phase current of the faulted phase is The resistance of the un-short-circuited portion of the winding in the faulty phase , self-awareness , back electromotive force is The resistance of the short-circuited portion of the winding in the faulty phase , self-awareness , back electromotive force is .
[0029] When a permanent magnet synchronous motor is running, the short-circuit resistance of the faulty phase Short-circuit current will flow through it. This disrupts the original balanced torque output, causing the motor's output torque to become:
[0030] in, It is the phase current of a permanent magnet synchronous motor. It is the back electromotive force. It is the mechanical angular velocity. Short-circuit turns ratio. It is the proportion of the number of turns of the faulty phase that are short-circuited to the total number of turns of the phase winding in a permanent magnet synchronous motor.
[0031] Compared to the motor output torque during normal operation After an inter-turn short circuit fault occurs, the output torque of the permanent magnet synchronous motor will have torque pulsation. Furthermore, the kinematic equations of a permanent magnet synchronous motor are:
[0032] in, This is the load torque of the permanent magnet synchronous motor. This represents the moment of inertia of the permanent magnet synchronous motor. Indicates time. That is, the excess in the motor's output torque. It will affect the mechanical angular velocity Subsequently, due to the rotational speed closed-loop effect, the current feed of the quadrature-axis current component in the fundamental plane is affected, and ultimately, due to the current closed-loop effect, the quadrature-axis current component in the fundamental plane is affected. This leads to the quadrature axis current component. A pulsating component appears. This method is applicable to three-phase or five-phase permanent magnet synchronous motors. For five-phase permanent magnet synchronous motors, the quadrature-axis current component in the fundamental plane is... That is Axis current.
[0033] Therefore, it can be determined that an inter-turn short-circuit fault in a permanent magnet synchronous motor will affect the quadrature-axis current component. Based on this, please refer to Figure 1 The control block diagram shown in this application indicates that the phase current of the permanent magnet synchronous motor is collected. Then, coordinate transformation is performed to obtain the cross-axis current components in the fundamental wave plane. Then, based on the quadrature axis current components Extracting current fault characteristic variables when an inter-turn short circuit occurs in a permanent magnet synchronous motor The amplitude and phase information, combined with the real-time electrical angle of the permanent magnet synchronous motor. Reconstruction yields current fault characteristic variables The characteristic variable of this current fault Short-circuit current used to characterize inter-turn short-circuit faults in permanent magnet synchronous motors Then, using current fault characteristic variables... Follow the expected amplitude of fault characteristic variables This paper proposes a closed-loop fault-tolerant control method for permanent magnet synchronous motors (PMSMs). This method suppresses short-circuit currents by reconstructing current fault characteristic variables and introducing closed-loop control, effectively reducing the overcurrent hazards caused by inter-turn short circuits and improving the fault-tolerant operation capability of PMSMs.
[0034] Furthermore, due to the quadrature axis current component Directly received The impact, The main factor affecting the short-circuit turns ratio is Short-circuit current flowing through the short-circuit resistance of the faulted phase The coupling effect between them, therefore in one embodiment, takes the current fault characteristic variable. The characteristic variable of this current fault It can fully reflect the severity of inter-turn short circuit faults in permanent magnet synchronous motors and is easy to obtain.
[0035] When a permanent magnet synchronous motor experiences an inter-turn short circuit fault, the quadrature axis current component... The pulsating components that appear With this current fault characteristic variable Closely related, as analyzed below: First, regarding torque ripple... The items can be expanded to include:
[0036] in, This refers to the number of phase windings in a permanent magnet synchronous motor, specifically a three-phase permanent magnet synchronous motor. Five-phase permanent magnet synchronous motor . It is the number of pole pairs of the motor. It is the flux linkage amplitude of the permanent magnet. It is a characteristic variable of current fault. amplitude, It is a characteristic variable of current fault. phase, It is the real-time electrical angle of the permanent magnet synchronous motor.
[0037] because Therefore, only torque ripple is considered. With cross-axis current component pulsating component The following relationships sometimes exist:
[0038] Therefore, by simultaneously solving the equations for the AC components, we can obtain:
[0039] Based on this, the quadrature-axis current component can be determined. The pulsating component generated during an inter-turn short-circuit fault The amplitude is equal to quadrature axis current component The pulsating component generated during an inter-turn short-circuit fault The phase is equal to .
[0040] Therefore, through the quadrature axis current component pulsating component The characteristic variables of the current fault can then be reconstructed. amplitude and phase Therefore, based on the quadrature axis current components... The amplitude and phase information of the characteristic variables of current faults includes: Please refer to Figure 3 The flowchart for the quadrature-axis current components When a Fast Fourier Transform (FFT) is performed, if a characteristic harmonic of a predetermined frequency for inter-turn short circuits exists in the FFT result, this characteristic harmonic is considered to be the quadrature-axis current component. The pulsating components that appear This confirms that the permanent magnet synchronous motor has an inter-turn short circuit fault, and the characteristic harmonics of this inter-turn short circuit can be used to determine the fault. Amplitude and phase information determine current fault characteristic variables Amplitude and phase information. When the quadrature-axis current component If the fast Fourier transform results do not contain characteristic harmonics of inter-turn short circuits at a predetermined frequency, it is determined that the permanent magnet synchronous motor does not have an inter-turn short circuit fault.
[0041] As mentioned above, quadrature axis current components The pulsating components that appear Torque pulsation This is caused by short-circuit current. and back electromotive force The frequencies are all related to the electric frequency of the motor. Consistent, therefore torque pulsation The actual frequency is The harmonics, due to the influence of the current closed loop, include the quadrature axis current component. The frequency will also appear in the middle. pulsating component Therefore, in the above embodiments, from the quadrature axis current component... The inter-turn short-circuit characteristic harmonics extracted from the Fast Fourier Transform results at a predetermined frequency are those with the motor frequency. Twice the second harmonic.
[0042] The electric frequency of the motor is extracted. Twice the second harmonic, also known as the pulsating component Then, the pulsation component can be obtained. amplitude and phase Then, based on the pulsation components determined above... Amplitude and phase information and current fault characteristic variables By understanding the relationship between the amplitude and phase information, the amplitude of the current fault characteristic variable can be extracted. And determine the phase of the characteristic variables of the current fault. Then the current fault characteristic variables can be reconstructed. .
[0043] This application implements fault-tolerant control of permanent magnet synchronous motors based on short-circuit current suppression. Please refer to [reference needed]. Figure 2 Calculate the expected amplitude of the pre-set fault characteristic variables. With current fault characteristic variables The difference between them yields the error signal. Then, this error signal is used. Corrected direct-axis current reference value in the fundamental plane The corrected direct-axis current reference value is obtained. This includes: transmitting error signals The input to the PI controller obtains the direct-axis current control quantity in the fundamental plane. Then, the direct-axis current control quantity With the given direct-axis current reference value The corrected direct-axis current reference value is obtained by superposition. .
[0044] For real-time electrical angle The real-time rotational speed is obtained by differentiation. Calculate the setpoint speed. With real-time speed The difference is input to the PI controller to obtain the quadrature axis current reference value. Then, based on the quadrature axis current reference value and the corrected direct-axis current reference value The motor control signal is obtained to perform closed-loop fault-tolerant control on the permanent magnet synchronous motor. In this embodiment, a model predictive current control strategy is employed, including: using a current model to predict the phase current of the permanent magnet synchronous motor. Obtain the predicted value of the direct-axis current. and cross-axis current prediction value Then, the value function is used to minimize... and The optimal voltage vector is selected to determine the motor control signal for the permanent magnet synchronous motor, thereby effectively suppressing current disturbances caused by inter-turn short-circuit faults while achieving speed control. Other motor control technologies can also be used in practice.
[0045] In a simulation example, the rotational speed is given by... The load setpoint is 5 Nm, and the expected amplitude of the fault characteristic variable is... In this simulation example, t =0.1s ago, the permanent magnet synchronous motor did not experience an inter-turn short circuit fault. tAn inter-turn short-circuit fault is injected into the A-phase winding at 0.1s. The torque, speed, and quadrature-axis current components of the permanent magnet synchronous motor are analyzed during the simulation. The timing waveform diagram is as follows Figure 4 As shown. Figure 4 It can be seen that, t If no inter-turn short circuit fault occurs 0.1s prior, the torque output is stable, the speed does not fluctuate significantly, and the quadrature axis current component... No second harmonic was observed. However, t At 0.1s, after an inter-turn short-circuit fault is injected into the A-phase winding, the quadrature-axis current component... Periodic pulsations appear immediately. The quadrature-axis current component is analyzed according to this method. Fourier transform is performed to obtain the amplitude and phase information of the second harmonic, and the current fault characteristic variables are then reconstructed. The time-series waveforms of the true and reconstructed values are shown below. Figure 5 As shown, by Figure 5 It can be seen that the reconstructed current fault characteristic variables The successful tracking of the true value within one electrical cycle demonstrates the speed and accuracy of the reconstruction method. Simultaneously, the reconstructed current fault characteristic variables... As feedback, the expected amplitude of the fault characteristic variable After comparison, the error is input into the PI controller to begin correcting the motor control signal and suppressing short-circuit current. The proportional part of the PI controller makes the controlled variable quickly approach the setpoint, while the integral part eliminates steady-state error, improving control accuracy. The reconstructed current fault characteristic variable's timing waveforms before and after PI regulator adjustment are shown below. Figure 6 As shown, by Figure 6 It can be seen that within one electrical cycle, the current fault characteristic variable was successfully suppressed to the expected amplitude of the fault characteristic variable, proving the stability, accuracy and speed of the closed-loop structure.
[0046] In another simulation example, the rotational speed setpoint The load setpoint is 10 Nm, and the expected amplitude of the fault characteristic variable is... In this simulation example, t =0.05s ago, no inter-turn short circuit fault occurred in the permanent magnet synchronous motor. t An inter-turn short-circuit fault is injected into the A-phase winding at 0.05s. The torque, speed, and quadrature-axis current components of the permanent magnet synchronous motor are analyzed during the simulation. The timing waveform diagram is as follows Figure 7 As shown. Figure 7 It can be seen that, t If no inter-turn short circuit fault occurs 0.05s prior, the torque output is stable, the speed does not fluctuate significantly, and the quadrature axis current component... No second harmonic was observed.t An inter-turn short-circuit fault is introduced at 0.05s, and the quadrature-axis current component... Periodic pulsations appear immediately; the quadrature-axis current component is analyzed according to this method. Fourier transform is performed to obtain the amplitude and phase information of the second harmonic, and the current fault characteristic variables are then reconstructed. The time-series waveforms of the true and reconstructed values are shown below. Figure 8 As shown, by Figure 8 It can be seen that the reconstructed current fault characteristic variables The successful tracking of the true value within one electrical cycle demonstrates the speed and accuracy of the reconstruction method. Simultaneously, the reconstructed current fault characteristic variables... As feedback, the expected amplitude of the fault characteristic variable After comparison, the error is input into the PI controller to begin correcting the motor control signal and suppressing short-circuit current. The proportional part of the PI controller makes the controlled variable quickly approach the setpoint, while the integral part eliminates steady-state error, improving control accuracy. The reconstructed current fault characteristic variable's timing waveforms before and after PI regulator adjustment are shown below. Figure 9 As shown, by Figure 9 It can be seen that within one electrical cycle, the current fault characteristic variable was successfully suppressed to the expected amplitude of the fault characteristic variable, proving the stability, accuracy and speed of the closed-loop structure.
[0047] The two simulation examples above demonstrate that, under different operating conditions, this method can accurately reconstruct fault characteristic variables and quickly close the loop to suppress short-circuit current, proving the method's good response capability and robustness.
[0048] The above descriptions are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations that can be directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.
Claims
1. A fault-tolerant control method for a permanent magnet synchronous motor based on short-circuit current suppression, characterized in that, The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression includes: The phase current of the permanent magnet synchronous motor is collected and coordinate transformation is performed to obtain the quadrature-axis current component in the fundamental plane. ; Based on the quadrature axis current component The amplitude and phase information of the current fault characteristic variables of the fault phase when an inter-turn short circuit occurs in a permanent magnet synchronous motor are extracted and combined with the real-time electrical angle of the permanent magnet synchronous motor. Reconstruction yields current fault characteristic variables ; Current fault characteristic variables Follow the expected amplitude of fault characteristic variables To achieve closed-loop fault-tolerant control of the permanent magnet synchronous motor.
2. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 1, characterized in that, Current fault characteristic variables , It is the proportion of the number of turns of the faulty phase that are short-circuited to the total number of turns in the phase winding of a permanent magnet synchronous motor. It is the short-circuit current flowing through the short-circuit resistance of the faulty phase.
3. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 2, characterized in that, Based on the quadrature axis current component The amplitude and phase information of the characteristic variables of current faults includes: Regarding the quadrature axis current component A Fast Fourier Transform (FFT) is performed. If the FFT result contains a characteristic harmonic of inter-turn short circuit at a predetermined frequency, it is determined that the permanent magnet synchronous motor has an inter-turn short circuit fault, and the amplitude and phase information of the current fault characteristic variable is determined based on the amplitude and phase information of the inter-turn short circuit characteristic harmonic. If the FFT result does not contain a characteristic harmonic of inter-turn short circuit at a predetermined frequency, it is determined that the permanent magnet synchronous motor does not have an inter-turn short circuit fault.
4. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 3, characterized in that, The characteristic harmonic of inter-turn short circuit is the second harmonic, which has a frequency twice that of the motor's electrical frequency.
5. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 3, characterized in that, The amplitude and phase information of the characteristic variables of the current fault, determined based on the amplitude and phase information of the characteristic harmonics of the inter-turn short circuit, includes: Determine the amplitude of characteristic variables of current faults And determine the phase of the characteristic variables of the current fault. ;in, It is the amplitude of the characteristic harmonics of the inter-turn short circuit with a predetermined frequency. It is the phase of the inter-turn short-circuit characteristic harmonic with a predetermined frequency. It refers to the number of phase windings in a permanent magnet synchronous motor.
6. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 1, characterized in that, Reconstruction yields current fault characteristic variables , It is based on the quadrature axis current component The amplitude of the extracted current fault characteristic variables, It is based on the quadrature axis current component The phase of the extracted current fault characteristic variables.
7. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 1, characterized in that, Current fault characteristic variables Follow the expected amplitude of fault characteristic variables Closed-loop fault-tolerant control of permanent magnet synchronous motors for the target purpose includes: Calculate the expected amplitude of fault characteristic variables With current fault characteristic variables The difference between them yields the error signal. ; Using error signals Corrected direct-axis current reference value in the fundamental plane The corrected direct-axis current reference value is obtained. ; Based on the cross-axis current reference value and the corrected direct-axis current reference value The motor control signal is obtained to perform closed-loop fault-tolerant control on the permanent magnet synchronous motor.
8. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 7, characterized in that, Using error signals Corrected direct-axis current reference value in the fundamental plane The corrected direct-axis current reference value is obtained. include: Error signal The input to the PI controller obtains the direct-axis current control quantity in the fundamental plane. ; Direct-axis current control quantity Compared with direct-axis current reference value The corrected direct-axis current reference value is obtained by superposition. .
9. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 7, characterized in that, Based on the cross-axis current reference value and the corrected direct-axis current reference value Obtaining motor control signals for controlling permanent magnet synchronous motors includes: The direct-axis current prediction value is obtained based on the phase current of the permanent magnet synchronous motor using a current model. and cross-axis current prediction value ; Using the value function to minimize and Determine the motor control signal for the target.
10. The fault-tolerant control method for permanent magnet synchronous motors based on short-circuit current suppression according to claim 1, characterized in that, The method is applicable to three-phase permanent magnet synchronous motors or five-phase permanent magnet synchronous motors.