High-speed permanent magnet motor rotor position estimation precision optimization method and system

Abstract

The invention discloses a high-speed permanent magnet motor rotor position estimation precision optimization method and system. The method comprises the steps of calculating a voltage vector estimation value # imgabs4 # at the starting moment of a # imgabs3 # period according to # imgabs0 # period and # imgabs2 # shaft output voltage of a # imgabs1 # period; acquiring a first-order differential of a # imgabs6 # shaft current at the starting moment of a # imgabs5 # period by adopting a current differential method; a back electromotive force observer is adopted to obtain back electromotive force estimated values # imgabs9 # and # imgabs10 # of a # imgabs8 # shaft in a # imgabs7 # period, and then a phase-locked loop (PLL) is adopted to obtain a rotor position angle # imgabs12 # and a motor electric angular speed # imgabs13 # estimated in a # imgabs11 # period. The invention aims to optimize the # imgabs14 # shaft voltage value input into the observer, reduce the discrete error of the # imgabs15 # shaft current differential term, improve the observation precision of the counter electromotive force, solve the problem of advanced estimation angle caused by digital control delay of the phase-locked loop, and improve the angle estimation precision of the phase-locked loop.

Description

Technical Field

[0001] The present invention belongs to the technical field of permanent magnet motor control, and in particular relates to a method and system for optimizing the accuracy of high-speed permanent magnet motor rotor position estimation. Background Art

[0002] For the digital control system of permanent magnet motor, the motor's own characteristics can be used to obtain rotor position information, so as to realize position sensorless control. However, when the motor is running at high speed, the control chip operation speed and sampling frequency are limited, the control and sampling times within a fundamental cycle are reduced, and the control delay increases, resulting in a larger digital control error. At the same time, as the carrier ratio decreases, the discretization error will continue to increase, and eventually affect the accuracy of position sensorless control. In order to solve the problem of increasing angle estimation error at high speed, existing research mainly reduces the error through external and internal compensation methods; for the external method, one method is to use fixed angle value compensation to reduce the angle error, but as the motor speed changes, the size of the angle error will also change, the effect of error compensation will deteriorate, affecting the accuracy of position sensorless control. For the internal compensation method, one method is to reduce the error caused by digital control delay by compensating the amplitude and phase of the output voltage of the control algorithm, but for position sensorless control, it does not conduct further research on the time consistency of the observer input, and the resulting angle estimation error still exists; another method is to estimate the rotor position through a high-order phase-locked loop to reduce the rotor position estimation deviation, but this method increases the complexity of the system. At the same time, if the back-EMF accuracy of the input phase-locked loop cannot be guaranteed, the estimated rotor position will still have a large error. Summary of the invention

[0003] The technical problem to be solved by the present invention is: In view of the above problems in the prior art, a method and system for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor is provided. In the axis coordinate system, the voltage value of the input observer is optimized, the discrete error of the current differential term is reduced, the observation accuracy of the back EMF is improved, and the problem of estimated angle advance caused by the delay of the phase-locked loop digital control is solved to improve the accuracy of the phase-locked loop angle estimation.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: A method for optimizing the accuracy of high-speed permanent magnet motor rotor position estimation comprises the following steps: S1, get the Cycle, cycle Axis voltage value , and , According to the average value equivalent principle of SVPWM, the Cycle start time Estimated shaft voltage , ; S2, using the current differential method to obtain the Cycle start time The first-order differential of the shaft current; S3, according to Cycle start time Estimated shaft voltage , And the current value , , the back EMF observer is used to obtain the Cycle start time Estimated value of the back EMF of the shaft , ; S4, according to cycle Estimated value of the back EMF of the shaft , The first Cycle estimated rotor position angle and the motor electrical angular velocity .

[0005] Optionally, in step S1, the average value equivalent principle of SVPWM is used to calculate the first Cycle start time Estimated shaft voltage , The function expression is: , , in, and Respectively Cycle start time Estimated value of shaft voltage, and Respectively -1 cycle output Shaft voltage, and Respectively -2 cycle output Shaft voltage.

[0006] Optionally, in step S2, a current differential method is used to obtain the current Cycle start time Estimated shaft voltage , At the same time The function expression of the first-order differential of the shaft current is: , in, and Respectively Cycle start time The first-order differential of the shaft current, For the The motor electrical angular velocity of the cycle, and Respectively Cycle start time Shaft current, For the Periodically estimated motor electrical angular velocity.

[0007] Optionally, in step S3, a back electromotive force observer is used to obtain the first Cycle start time Estimated shaft back EMF , The function expression is: , in, and Respectively Cycle start time Estimated value of shaft back EMF, and Respectively Cycle start time Estimated value of shaft voltage, represents the motor stator resistance, and Respectively Cycle start time Shaft current, For the The motor electrical angular velocity estimated by the cycle, , They represent the motor d-axis and q-axis inductances respectively.

[0008] Optionally, in step S4, according to Cycle start time Estimated value of the back EMF of the shaft , The first Cycle estimated rotor position angle and the motor electrical angular velocity include: S4.1, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference ; S4.2, based on the actual rotor position angle and the estimated rotor position angle The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle ; S4.3, Motor electrical angular velocity estimated by cycle The angle is accumulated by the integrator to obtain the Cycle estimated rotor position angle .

[0009] Optionally, in step S4.1, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference The function expression is: , in, and Respectively Cycle start time Estimated value of shaft back EMF, For the The periodically estimated rotor position angle, For the The motor electrical angular velocity estimated by the cycle, To control the cycle.

[0010] Optionally, in step S4.2, the actual rotor position angle is compared with the estimated rotor position angle. The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle The function expression is: , in, Based on -1 cycle estimates the correction amount of the electrical angular velocity, and based on the -1 cycle estimated electrical angular velocity correction To compare the actual rotor position angle with the estimated rotor position angle The difference After inputting into the PI controller, we get:

[0011] In addition, the present invention also provides a high-speed permanent magnet motor rotor position estimation accuracy optimization system, comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method.

[0012] In addition, the present invention also provides a computer-readable storage medium, in which a computer program or instruction is stored. The computer program or instruction is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method through a processor.

[0013] In addition, the present invention also provides a computer program product, including a computer program or instructions, which are programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method through a processor.

[0014] Compared with the prior art, the present invention mainly has the following advantages: Under high-speed control, the position estimation error is mainly composed of two parts: back-EMF estimation error and phase-locked loop error. The causes and solutions of the error are as follows: When observing the back-EMF of a high-speed permanent magnet motor, the traditional method The shaft input current is sampled and calculated at the beginning of this control cycle; however, due to the delay of digital control, The axis input voltage is solved in the previous control cycle, and the reconstructed voltage average value sent by SVPWM in this control cycle. Therefore, to ensure that the observer input voltage and current are instantaneous values ​​at the same time, it is necessary to The shaft input voltage is optimized to improve the estimation accuracy of the back EMF. In terms of back EMF calculation, the traditional method uses the differential method to directly solve the current differential term, which will lead to the amplification of the noise signal. For this reason, a separate filtering link needs to be designed, which increases the complexity of the system. Under the condition that the control period remains unchanged, as the motor speed increases, the truncation error of the differential method will also increase. Therefore, it is necessary to optimize the current differential solution method to improve the accuracy of the differential calculation and reduce the estimation error of the back EMF. In terms of rotor position estimation, the solved The shaft back EMF is input into the phase-locked loop. Considering the delay of digital control, the internal feedback angle of the phase-locked loop is the angle estimated in the previous cycle. If this angle is used to solve the rotor position deviation signal of this cycle, the final estimated angle of the phase-locked loop will be one control cycle ahead of the actual angle. Therefore, it is necessary to compensate the feedback angle of the phase-locked loop to reduce the error of angle estimation and optimize the performance of position sensorless control. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a basic flow chart of the method of the present invention.

[0016] Figure 2 for Schematic diagram of the voltage output, function and current sampling timing of the axis.

[0017] Figure 3 It is a schematic diagram of the given voltage vector output, action timing and optimization solution.

[0018] Figure 4 For the The cycle starts at Shaft voltage The actual motor Shaft voltage waveform.

[0019] Figure 5 For the Cyclic Shaft voltage The actual motor Shaft voltage waveform.

[0020] Figure 6 For the method of the present invention The shaft current derivative and the actual motor Shaft current derivative waveform.

[0021] Figure 7 For the traditional difference method The shaft current derivative and the actual motor Shaft current derivative waveform.

[0022] Figure 8 The method of the present invention obtains Waveforms of shaft back EMF and actual motor back EMF.

[0023] Fig. 9 Obtained by traditional methods Waveforms of shaft back EMF and actual motor back EMF.

[0024] Fig.10 Schematic diagram of the phase-locked loop angle deviation signal compensation method under digital control.

[0025] Fig.11Schematic diagram of position sensorless control of a high-speed permanent magnet motor according to an embodiment of the present invention.

[0026] Fig.12 This is a waveform diagram of the rotor position estimated by the method of the present invention and the actual rotor position of the motor.

[0027] Fig.13 The waveforms of the rotor position estimated by the traditional method and the actual rotor position of the motor. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figure 1 As shown, the method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor in this embodiment includes the following steps: S1, get the Cycle, Cyclic Shaft output voltage and According to the average value equivalent principle of SVPWM, the The cycle starts at Shaft voltage vector estimate ; S2, using the current differential method to obtain the The cycle starts at Shaft current; S3, according to The cycle starts at Shaft voltage vector estimate and The cycle starts at The shaft current is obtained by using the back-EMF observer. Cyclic Estimated shaft back EMF ; S4, according to Cyclic Estimated shaft back EMF The first Cycle estimated rotor position angle and the motor electrical angular velocity .

[0030] At the beginning of the kth control cycle, and Input into SVPWM and send out pulse signal. According to the average value equivalent principle of SVPWM, and is the average value of SVPWM action in the kth control cycle; similarly, and is the average value of SVPWM action in the k-1th control cycle; based on the midpoint principle, in step S1 of this embodiment, the average value equivalent principle of SVPWM is used to calculate the k-1th control cycle. Cycle start time Estimated shaft voltage , The function expression is: , , in, and Respectively Cycle start time Estimated value of shaft voltage, and Respectively -1 cycle output Shaft voltage, and Respectively -2 cycle output Shaft voltage.

[0031] When performing double closed-loop control, consider the delay of digital control. The shaft given voltage has about The delay of is the control cycle. During this process, the motor has rotated 1.5 The angle of the control delay compensation Cyclic Shaft output voltage , The calculation function expression is: , , in, represents any non-zero positive integer, represents the control cycle, Indicates The motor electrical angular velocity estimated by the cycle, Indicates The periodically estimated rotor position angle, , Respectively represent cycle d , q Axis given voltage, , Respectively -1 cycle output shaft voltage; similarly, , Respectively -2 cycle output Shaft voltage. Figure 2 In the example, (k-2)T s 、(k-1)T s , kT s Three cycles The timing of shaft voltage output, action and current sampling. At the beginning of each control cycle, the current of the high-speed permanent magnet motor is sampled; among them, (k-2)T s 、(k-1)T s of After a delay of one control cycle, the shaft output voltage is at (k-1)T s , kT s It is sent to SVPWM and sends pulses. According to the average value equivalent principle of SVPWM, the input SVPWM The shaft voltage is the average value of the entire control cycle, which is indicated by the dotted line in the figure. Therefore, it can be calculated by s , kT s Cycle SVPWM Average shaft voltage , and , Solve to get the starting time of the kth cycle Shaft voltage , . Figure 3 Shown The specific method of the axis output voltage vector action timing and optimization solution is based on the triangle midpoint principle, using the output voltage of the first two cycles to solve the kth cycle start time Shaft voltage , . Figure 4 , Figure 5 are the starting time of the kth cycle respectively Estimated shaft voltage and the k-1th cycle Shaft output voltage The actual motor Comparison of shaft voltage waveforms: At the beginning of each control cycle, compared with the actual motor voltage Shaft voltage value, obtained by optimization The deviation is small, and the k-1 period Shaft voltage There is a large deviation.

[0032] Aiming at the problem that the differential method directly solves the current differential term, which leads to noise amplification and back EMF calculation error, based on The current expression in the coordinate system can directly obtain the current differential result by derivation and equation substitution, avoiding the error caused by solving the problem using the difference method. The optimization solution method for the shaft current differential term is as follows: , in, and Respectively Cycle start time Shaft current, is the current amplitude, represents the motor electrical angular velocity, For time, and Respectively Cycle start time The first-order differential (derivative) of the shaft current. Discretization processing is performed on this basis to obtain the current differential method used in step S2 of this embodiment to obtain the first-order differential (derivative) of the shaft current. Cycle start time Estimated shaft voltage , At the same time The function expression of the first-order differential of the shaft current is: , in, and Respectively Cycle start time The first-order differential of the shaft current, For the The motor electrical angular velocity of the cycle, and Respectively Cycle start time Shaft current, For the Periodically estimated motor electrical angular velocity. Figure 6 , Figure 7 are obtained by the method of this embodiment and the traditional method respectively. The first-order derivative of the shaft current is related to the actual Comparing the first-order derivative of the shaft current, at the beginning of each control cycle, compared with the actual first-order derivative of the current, the first-order derivative of the current obtained in this embodiment has a smaller deviation, while the first-order derivative of the current solved by the traditional difference method has a larger deviation.

[0033] As an optional implementation, in step S3, a back electromotive force observer is used to obtain the first Cycle start time Estimated shaft back EMF , The function expression is: , Since when calculating the back EMF in the kth cycle, The solution has not been performed yet. Considering that the motor speed cannot change suddenly and the speed change between two control cycles is very small, the error can be ignored. Therefore, the above formula uses In addition, as an optimized implementation, in step S3, a back electromotive force observer is used to obtain the first Cycle start time Estimated shaft back EMF , The function expression is: , in, and Respectively Cycle start time Estimated value of shaft back EMF, and Respectively Cycle start time Estimated value of shaft voltage, represents the motor stator resistance, and Respectively Cycle start time Shaft current, For the The motor electrical angular velocity estimated by the cycle, , They represent the motor d-axis and q-axis inductances respectively. Figure 8 , Fig. 9 are obtained by the method of this embodiment respectively The axis back EMF and the traditional method Comparing the shaft back EMF with the actual motor back EMF, at the beginning of each control cycle, the back EMF solved by the present embodiment is almost equal to the actual motor back EMF, while the back EMF solved by the traditional method has a large deviation.

[0034] In step S4 of this embodiment, Cycle start time Estimated value of the back EMF of the shaft , The first Cycle estimated rotor position angle and the motor electrical angular velocity include: S4.1, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference ; S4.2, based on the actual rotor position angle and the estimated rotor position angle The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle ; S4.3, Motor electrical angular velocity estimated by cycle The angle is accumulated by the integrator to obtain the Cycle estimated rotor position angle .

[0035] will be solved The axis back EMF is input into the phase-locked loop. In the kth control cycle, the phase-locked loop feedback angle is the estimated angle of the previous cycle, which causes the final estimated angle to be one cycle ahead of the previous cycle. No solution has been found yet, so we choose to use , by directly adding a control cycle angle to the phase-locked loop feedback angle , to solve the problem of the angle estimation being ahead in the kth cycle. cycle Estimated shaft back EMF , and the actual rotor position angle of the motor in the kth cycle The relationship is as follows: , in, and Respectively cycle Estimated value of shaft back EMF, For the cycle The magnitude of the estimated shaft back EMF.

[0036] By performing angle compensation on the phase-locked loop feedback angle for one control cycle, the estimated rotor position angle of the kth cycle can be approximately solved as follows: , in, and Respectively Cycle and -1 cycle estimated rotor position angle, For the The motor electrical angular velocity estimated by the cycle, To control the cycle.

[0037] In step S4.1 of this embodiment, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference The function expression is: , in, and Respectively Cycle start time Estimated value of shaft back EMF, For the The periodically estimated rotor position angle, For the The motor electrical angular velocity estimated by the cycle, is the control period. And: , , in, For the cycle The magnitude of the estimated shaft back EMF.

[0038] In step S4.2 of this embodiment, the actual rotor position angle and the estimated rotor position angle are compared. The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle The function expression is: , in, Based on -1 cycle estimates the correction amount of the electrical angular velocity, and the Correction of periodic estimated electrical angular velocity To compare the actual rotor position angle with the estimated rotor position angle The difference After inputting into the PI controller, we get Fig.10 In the calculation, the estimated start time of the kth cycle is The axis back EMF is input to the phase-locked loop, and the angle of the control cycle is added to the feedback angle in the k-1 cycle. , a more accurate deviation signal is obtained, which is successively passed through the PI controller, the integrator Get the estimated rotor position angle. Fig.10 As shown, according to the direction of the arrow, in the kth control cycle, it is necessary to estimate , we need to solve , then After PI and integrator Estimated Here the PI controller acts as a controller in the k-1th cycle. Correction based on , and then get the kth cycle .Then Then input the integrator In the example, based on the estimated angle of the k-1 period, the estimated angle value of the kth period is obtained by angle accumulation. The method of this embodiment mainly compensates for The solution value of It is still unknown, but this angle needs to be used in advance. Therefore, the method of this embodiment approximately solves the kth cycle by using the phase-locked loop feedback angle compensation method. ( ), and then the actual rotor position of the motor in the kth cycle The rotor position approximately solved for the kth period Difference , which improves The solution accuracy (the traditional method does not compensate and directly feeds back in the phase-locked loop ). Here through After approximate compensation, we get , when the motor speed changes or there is an error in the estimated speed, the approximate compensation will definitely have a deviation, that is, , and then Input into the PI controller. First, from the previous formula, we can know: 1. If the value after compensation ,Right now , then the correction value of the kth cycle output by the PI controller is , that is, the output of the PI controller Increase, compared with the estimated angle obtained by uncorrected estimated electrical angular velocity, the integrator Output angle 2. If the value after compensation ,Right now , then the correction value of the kth cycle output by the PI controller is , that is, the output of the PI controller Compared with the estimated angle obtained without correcting the estimated electrical angular velocity, the integrator Output angle Will be reduced. Fig.11 The overall control block diagram of the rotor position estimation accuracy optimization method of this embodiment is as follows: The double closed-loop control framework, when running to the kth control cycle, obtains the start time of this cycle by calculation Estimated shaft voltage , , sampling k The current value at the beginning of the cycle, based on The differential solution method of the shaft current expression is used to solve the k Cycle start time The back EMF of the shaft is extracted and estimated using an improved phase-locked loop to obtain relatively accurate electrical angular velocity and rotor position, and the above-mentioned solution values ​​are fed back to the double closed-loop control system to achieve position sensorless control of the high-speed permanent magnet motor. Fig.12 , Fig.13 The rotor position estimated by the method of this embodiment and the rotor position estimated by the traditional method are compared with the actual rotor position of the motor. At the beginning of each control cycle, the rotor position estimated by the method of this embodiment is almost equal to the actual rotor position of the motor, while the rotor position estimated by the traditional method has a large deviation.

[0039] In summary, in this embodiment, The dual closed-loop control strategy is used to control the high-speed permanent magnet motor. At the beginning of the kth cycle, based on the k-1 and k-2 cycles The output voltage of the axis is used to calculate the start time of the kth cycle. The voltage of the axis; ignoring the error of the current sampling circuit, the current sampling and calculation at the beginning of this cycle is The shaft current is an accurate value, which ensures The voltage and current of the shaft are the values ​​at the same time during the operation of the motor; compared with the traditional direct use of k-1 cycle The shaft output voltage is The shaft voltage is optimized and then input into the back-EMF observer to improve the accuracy of back-EMF estimation. The current expression in the coordinate system can be directly obtained by differentiating the expression and substituting the equation. Compared with the traditional differential solution method, this method avoids the introduction of noise signals into the system, effectively reduces the discrete error of the current differential term under high-speed and low-carrier ratio conditions, and ultimately improves the estimation accuracy of the back EMF. Based on the solved back EMF, it is input into the phase-locked loop after feedback angle compensation to estimate the rotor position angle. In the kth control cycle, the angle deviation input of the PI controller is the difference between the actual rotor position of the kth cycle and the estimated rotor position of the kth cycle. This makes the estimated rotor position of the final output extremely close to the actual rotor position. Therefore, this compensation method solves the problem of estimated angle advance caused by the delay of the phase-locked loop digital control and improves the accuracy of the phase-locked loop angle estimation. In addition, this embodiment also provides a high-speed permanent magnet motor rotor position estimation accuracy optimization system, including a microprocessor and a memory connected to each other, and the microprocessor is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method.

[0040] In addition, this embodiment also provides a computer-readable storage medium, in which a computer program or instruction is stored. The computer program or instruction is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method through a processor.

[0041] In addition, this embodiment also provides a computer program product, including a computer program or instructions, which are programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method through a processor.

[0042] Those skilled in the art should understand that the technical solutions provided by the embodiments of the present application may be in the form of methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the process Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including an instruction device, which implements the functions specified in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide for implementing the process in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0043] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for optimizing the accuracy of high-speed permanent magnet motor rotor position estimation, characterized in that: The steps include: S1, get the Cycle, cycle Axis voltage value , and , According to the average value equivalent principle of SVPWM, the Cycle start time Estimated shaft voltage , ; S2, using the current differential method to obtain the Cycle start time The first-order differential of the shaft current; S3, according to Cycle start time Estimated shaft voltage , And the current value , , the back EMF observer is used to obtain the Cycle start time Estimated value of the shaft back EMF , ; S4, according to cycle Estimated value of the back EMF of the shaft , The first Cycle estimated rotor position angle and the motor electrical angular velocity .

2. The method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor according to claim 1, characterized in that: In step S1, the average value equivalent principle of SVPWM is used to calculate the first Cycle start time Estimated shaft voltage , The function expression is: ， ， in, and Respectively Cycle start time Estimated value of shaft voltage, and Respectively -1 cycle output Shaft voltage, and Respectively -2 cycle output Shaft voltage.

3. The method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor according to claim 1, characterized in that: In step S2, a current differential method is used to obtain the current Cycle start time Estimated shaft voltage , At the same time The function expression of the first-order differential of the shaft current is: ， in, and Respectively Cycle start time The first-order differential of the shaft current, For the The motor electrical angular velocity of the cycle, and Respectively Cycle start time Shaft current, For the Periodically estimated motor electrical angular velocity.

4. The method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor according to claim 1, characterized in that: In step S3, a back electromotive force observer is used to obtain the Cycle start time Estimated value of the back EMF of the shaft , The function expression is: ， in, and Respectively Cycle start time Estimated value of shaft back EMF, and Respectively Cycle start time Estimated value of shaft voltage, represents the motor stator resistance, and Respectively Cycle start time Shaft current, For the The motor electrical angular velocity estimated by the cycle, , They represent the motor d-axis and q-axis inductances respectively.

5. The method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor according to claim 1, characterized in that: In step S4, according to Cycle start time Estimated value of the shaft back EMF , The phase-locked loop (PLL) is used to obtain the Cycle estimated rotor position angle and the motor electrical angular velocity include: S4.1, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference : S4.2, based on the actual rotor position angle and the estimated rotor position angle The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle ; S4.3, Motor electrical angular velocity estimated by cycle The angle is accumulated by the integrator to obtain the Cycle estimated rotor position angle .

6. The method for optimizing the high-speed permanent magnet motor rotor position estimation accuracy according to claim 5, characterized in that: In step S4.1, according to Cycle start time Estimated value of the back EMF of the shaft , Calculate the actual rotor position angle and Cycle estimated rotor position angle The difference The function expression is: ， in, and Respectively Cycle start time Estimated value of shaft back EMF, For the The periodically estimated rotor position angle, For the The motor electrical angular velocity estimated by the cycle, To control the cycle.

7. The method for optimizing the high-speed permanent magnet motor rotor position estimation accuracy according to claim 6, characterized in that: In step S4.2, the actual rotor position angle and the estimated rotor position angle are compared. The difference For Motor electrical angular velocity estimated by cycle Correction is made to obtain Motor electrical angular velocity estimated by cycle The function expression is: ， in, For the The correction amount of the electrical angular velocity is estimated periodically, and the Correction of periodic estimated electrical angular velocity To compare the actual rotor position angle with the estimated rotor position angle The difference After inputting into the PI controller, we get:

8. A high-speed permanent magnet motor rotor position estimation accuracy optimization system, comprising a microprocessor and a memory connected to each other, characterized in that: The microprocessor is programmed or configured to execute the method for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor as described in any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program or instruction stored therein, characterized in that: The computer program or instruction is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method described in any one of claims 1 to 7 through a processor.

10. A computer program product comprising a computer program or instructions, characterized in that The computer program or instruction is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method described in any one of claims 1 to 7 through a processor.

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