A method and system for optimizing the accuracy of rotor position estimation for high-speed permanent magnet motors

Abstract

This invention discloses a method and system for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor. The method includes calculating the voltage vector estimate at the beginning of the first cycle based on the shaft output voltages of the first and second cycles; obtaining the first-order derivative of the shaft current at the beginning of the first cycle using a current differentiation method; obtaining the estimated back EMF of the shaft in the first cycle using a back EMF observer; and then obtaining the estimated rotor position angle and motor electrical angular velocity in the first cycle through a phase-locked loop (PLL). This invention aims to optimize the shaft voltage value input to the observer, reduce the discrete error of the shaft current derivative term, improve the observation accuracy of the back EMF, and solve the problem of estimated angle lead caused by the delay in PLL digital control, thereby improving the accuracy of PLL angle estimation.

Description

Technical Field

[0001] This invention belongs to the field of permanent magnet motor control technology, specifically relating to a method and system for optimizing the accuracy of rotor position estimation for a high-speed permanent magnet motor. Background Technology

[0002] For digital control systems of permanent magnet motors, rotor position information can be obtained using the motor's inherent characteristics, thus achieving sensorless control. However, when the motor operates at high speeds, the number of control and sampling operations per fundamental cycle decreases due to limitations in the control chip's processing speed and sampling frequency. This increases control delay, leading to larger digital control errors. Furthermore, as the carrier ratio decreases, discretization errors also amplify, ultimately impacting the accuracy of sensorless control. To address the issue of increased angle estimation errors at high speeds, existing research primarily employs external and internal compensation methods to reduce errors. One external method uses fixed angle value compensation to reduce angle errors; however, as the motor speed changes, the magnitude of the angle error also changes, diminishing the effectiveness of error compensation and affecting the accuracy of sensorless control. For internal compensation methods, one approach is to reduce the error caused by digital control delay by compensating for the amplitude and phase of the output voltage of the control algorithm. However, for sensorless control, this approach does not further study the time consistency of the observer input, and the resulting angle estimation error still exists. Another approach is to estimate the rotor position using a high-order phase-locked loop to reduce the rotor position estimation deviation. However, this approach increases the complexity of the system, and 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 this invention: Addressing the aforementioned problems in the prior art, this invention provides a method and system for optimizing the rotor position estimation accuracy of a high-speed permanent magnet motor. In the axial 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 lead caused by the delay of the phase-locked loop digital control is solved, thereby improving the accuracy of phase-locked loop angle estimation.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A method for optimizing the accuracy of rotor position estimation for a high-speed permanent magnet motor includes the following steps:

[0006] S1, obtain the first Period, First cycle Shaft voltage value , and , Calculate the first SVPWM average equivalent principle. Start of the cycle Voltage estimate of the shaft , ;

[0007] S2, the current differential method is used to obtain the first... Start of the cycle The first derivative of the shaft current;

[0008] S3, according to the Start of the cycle Voltage estimate of the shaft , and current value , The back potential observer is used to obtain the first Start of the cycle Back EMF estimate of the shaft , ;

[0009] S4, according to the cycle Back EMF estimate of the shaft , Obtain the first... through a phase-locked loop (PLL) Rotor position angle for period estimation and the electric angular velocity of the motor .

[0010] Optionally, in step S1, the first step is calculated based on the average value equivalent principle of SVPWM. Start of the cycle Voltage estimate of the shaft , The function expression is:

[0011] ,

[0012] ,

[0013] in, and The first Start of the cycle Estimated value of shaft voltage, and The first -1 cycle output shaft voltage, and The first -2 cycle output Shaft voltage.

[0014] Optionally, in step S2, the current differentiation method is used to obtain the current relative to the first... Start of the cycle Shaft voltage estimate , At the same time The functional expression for the first differential of the shaft current is:

[0015] ,

[0016] in, and The first Start of the cycle The first derivative of the shaft current For the first The periodic electric angular velocity of the motor, and The first Start of the cycle shaft current, For the first The electric angular velocity of the motor is estimated by period.

[0017] Optionally, in step S3, a back potential observer is used to obtain the first... Start of the cycle Back potential estimate , The function expression is:

[0018] ,

[0019] in, and The first Start of the cycle The estimated value of the back EMF of the shaft. and The first Start of the cycle Estimated value of shaft voltage, This represents the stator resistance of the motor. and The first Start of the cycle shaft current, For the first The electric angular velocity of the motor is estimated by period. , These represent the d-axis and q-axis inductances of the motor, respectively.

[0020] Optionally, in step S4, according to the first Start of the cycle Back EMF estimate of the shaft , Obtain the first... through a phase-locked loop (PLL) Rotor position angle for period estimation and the electric angular velocity of the motor include:

[0021] S4.1, according to the first Start of the cycle Back EMF estimate of the shaft , Calculate the actual rotor position angle and the first Rotor position angle for period estimation The difference ;

[0022] S4.2, based on the actual rotor position angle and the estimated rotor position angle The difference For the Electric angular velocity of motor estimated by period After making corrections, the first Electric angular velocity of motor estimated by period ;

[0023] S4.3, will the first Electric angular velocity of motor estimated by period The first angle is obtained by accumulating the angles using the integrator. Rotor position angle for period estimation .

[0024] Optionally, in step S4.1, according to the first Start of the cycle Back EMF estimate of the shaft , Calculate the actual rotor position angle and the first Rotor position angle for period estimation The difference The function expression is:

[0025] ,

[0026] in, and The first Start of the cycle The estimated value of the back EMF of the shaft. For the first Rotor position angle for period estimation For the first The electric angular velocity of the motor is estimated by period. To control the cycle.

[0027] Optionally, in step S4.2, the actual rotor position angle and the estimated rotor position angle are compared... The difference For the Electric angular velocity of motor estimated by period After making corrections, the first Electric angular velocity of motor estimated by period The function expression is:

[0028] ,

[0029] in, For the first The correction amount for estimating the electric angular velocity in period -1, and based on the first period. -1 period estimation correction amount of electric angular velocity To compare the actual rotor position angle with the estimated rotor position angle The difference The result is obtained after inputting into the PI controller.

[0030] Furthermore, the present invention also provides a high-speed permanent magnet motor rotor position estimation accuracy optimization system, including a microprocessor and a memory interconnected thereto, wherein the microprocessor is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method.

[0031] Furthermore, the present invention also provides a computer-readable storage medium storing a computer program or instructions that are programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method by a processor.

[0032] 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 by a processor.

[0033] Compared with the prior art, the present invention has the following main advantages:

[0034] Under high-speed control, the position estimation error mainly consists of two parts: back EMF estimation error and phase-locked loop error. The causes and solutions for these errors are as follows: When observing the back EMF of a high-speed permanent magnet motor, traditional methods... The shaft input current is sampled and calculated at the beginning of this control cycle; however, due to the delay of digital control, The shaft input voltage is calculated in the previous control cycle, while the average reconstructed voltage is sent via SVPWM in the current control cycle. Therefore, to ensure that the observer input voltage and current are instantaneous values ​​at the same moment, it is necessary to adjust the observer... The shaft input voltage is optimized to improve the accuracy of back EMF estimation. In back EMF calculation, the traditional method uses the finite difference method to directly solve the current differential term, which leads to amplification of noise signals. Therefore, a separate filtering stage is needed, increasing system complexity. Furthermore, under the condition of a constant control cycle, the truncation error of the finite difference method increases with the increase of motor speed. Therefore, the current differential solution method needs to be optimized to improve the accuracy of the differential calculation and reduce the estimation error of back EMF. In rotor position estimation, the solved... When the shaft back EMF is input into the phase-locked loop (PLL), considering the delay of digital control, the feedback angle inside the PLL is the angle estimated in the previous cycle. If this angle is used to solve the rotor position deviation signal in the current cycle, the final estimated angle of the PLL will lead the actual angle by one control cycle. Therefore, it is necessary to compensate the feedback angle of the PLL to reduce the angle estimation error and optimize the performance of sensorless control. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the basic process of the method of the present invention.

[0036] Figure 2 for A schematic diagram of the shaft's voltage output, function, and current sampling timing.

[0037] Figure 3 This diagram illustrates the given voltage vector output, timing, and optimization solution.

[0038] Figure 4 For the first The start of the period shaft voltage With the actual motor Shaft voltage waveform diagram.

[0039] Figure 5 For the first Periodic shaft voltage With the actual motor Shaft voltage waveform diagram.

[0040] Figure 6 The method of the present invention Shaft current derivative and actual motor Waveform of the derivative of the shaft current.

[0041] Figure 7 For traditional difference methods Shaft current derivative and actual motor Waveform of the derivative of the shaft current.

[0042] Figure 8 The method of the present invention is used to obtain Waveforms of shaft back EMF and actual motor back EMF.

[0043] Figure 9 Obtained by traditional methods Waveforms of shaft back EMF and actual motor back EMF.

[0044] Figure 10 This is a schematic diagram of a digitally controlled phase-locked loop (PLL) angle deviation signal compensation method.

[0045] Figure 11 This is a schematic diagram of sensorless control of a high-speed permanent magnet motor according to an embodiment of the present invention.

[0046] Figure 12 The waveform diagrams show the rotor position estimated by the method of the present invention and the actual rotor position of the motor.

[0047] Figure 13 The waveforms show the rotor position estimated by the traditional method and the actual rotor position of the motor. Detailed Implementation

[0048] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] like Figure 1 As shown, the high-speed permanent magnet motor rotor position estimation accuracy optimization method in this embodiment includes the following steps:

[0050] S1, obtain the first Period, First Periodic Shaft output voltage and Calculate the first SVPWM average equivalent principle. The start of the period Axis voltage vector estimate ;

[0051] S2, using the current differentiation method to obtain the first... The start of the period shaft current;

[0052] S3, according to the The start of the period Axis voltage vector estimate and the The start of the period The axis current is obtained by observing the back EMF observer. Periodic Back potential estimate ;

[0053] S4, according to the Periodic Back potential estimate Obtain the first... through a phase-locked loop (PLL) Rotor position angle for period estimation and the electric angular velocity of the motor .

[0054] At the start of the k-th control cycle, and The input is fed into the SVPWM and a pulse signal is emitted. According to the SVPWM average value equivalence principle, at this time... and This represents the average value of the SVPWM action during the k-th control cycle; similarly, and This represents the average value of the SVPWM action during the (k-1)th control cycle; based on the midpoint principle, in step S1 of this embodiment, the average value of SVPWM is calculated according to the equivalent principle of SVPWM. Start of the cycle Voltage estimate of the shaft , The function expression is:

[0055] ,

[0056] ,

[0057] in, and The first Start of the cycle Estimated value of shaft voltage, and The first -1 cycle output shaft voltage, and The first -2 cycle output Shaft voltage.

[0058] When implementing dual closed-loop control, the delay of digital control must be considered. The given voltage from the output to the SVPWM action has approximately [a certain duration]. The delay, of which This is for control cycle. During this process, the motor has already rotated 1.5... From the perspective of controlling the delay compensation, the first Periodic Shaft output voltage , The expression for the computation function is:

[0059] ,

[0060] ,

[0061] in, Represent any non-zero positive integer. Indicates the control period. Indicates the first The electric angular velocity of the motor is estimated by period. Indicates the first Rotor position angle for period estimation , They represent the first cycle d , q Shaft given voltage, , The first -1 cycle output Axis voltage; similarly, , The first -2 cycle output Axis voltage. Figure 2 The example shows (k-2)T. s (k-1)T s kT s Three cycles The timing sequence of shaft voltage output, action, and current sampling involves sampling the current of the high-speed permanent magnet motor at the beginning of each control cycle; where (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 The pulse is fed into the SVPWM and sent. According to the SVPWM average value equivalence principle, the input to the SVPWM at this time... The shaft voltage is the average value over the entire control cycle, as indicated by the dashed line in the diagram. Therefore, it can be determined by (k-1)T. s kT s The effect of periodic SVPWM average shaft voltage , and , Solving for the starting time of the k-th period yields... shaft voltage , . Figure 3 Showing The timing of the shaft output voltage vector action and the specific method for optimization are described. Based on the triangle midpoint principle, the output voltage of the first two cycles is used to solve for the starting time of the k-th cycle. shaft voltage , . Figure 4 , Figure 5 These are the start times of the k-th period. Shaft estimated voltage and the (k-1)th period Shaft output voltage With the actual motor A comparison of shaft voltage waveforms at the beginning of each control cycle, compared to the actual motor voltage. The shaft voltage value was obtained through optimized solution. The deviation is very small, while the (k-1)th period's shaft voltage There is a significant deviation.

[0062] To address the issues of noise amplification and back EMF calculation errors caused by directly solving the current differential term using the finite difference method, based on... The current expression in the coordinate system can be directly derived by differentiating and substituting equations, thus avoiding the errors introduced by using the finite difference method. The optimized solution method for the differential term of the shaft current is as follows:

[0063] ,

[0064] in, and The first Start of the cycle shaft current, The current amplitude, Indicates the electric angular velocity of the motor. For time, and The first Start of the cycle The first-order differential (derivative) of the shaft current. Based on this, discretization is performed to obtain the current differential method used in step S2 of this embodiment to obtain the derivative with respect to the first-order derivative. Start of the cycle Shaft voltage estimate , At the same time The functional expression for the first differential of the shaft current is:

[0065] ,

[0066] in, and The first Start of the cycle The first derivative of the shaft current For the first The periodic electric angular velocity of the motor, and The first Start of the cycle shaft current, For the first The electric angular velocity of the motor is estimated by period. Figure 6 , Figure 7 The results obtained using the method of this embodiment and the conventional method are respectively First derivative of shaft current and actual motor Comparing the first derivatives of the shaft current, at the beginning of each control cycle, the first derivative of the current obtained in this embodiment has a smaller deviation compared to the actual first derivative of the current, while the first derivative of the current obtained by the traditional difference method has a larger deviation.

[0067] As an optional implementation, step S3 uses a back potential observer to obtain the first... Start of the cycle Back potential estimate , The function expression is:

[0068] ,

[0069] Because when calculating the back electromotive force in the k-th period... The solution has not yet been performed. Considering that the motor speed cannot change abruptly and the speed change between two control cycles is extremely small, its error can be ignored. Therefore, the above formula uses... Calculations are performed. Furthermore, as an optimized implementation, step S3 uses a back potential observer to obtain the first... Start of the cycle Back potential estimate , The function expression is:

[0070] ,

[0071] in, and The first Start of the cycle The estimated value of the back EMF of the shaft. and The first Start of the cycle Estimated value of shaft voltage, This represents the stator resistance of the motor. and The first Start of the cycle shaft current, For the first The electric angular velocity of the motor is estimated by period. , These represent the d-axis and q-axis inductances of the motor, respectively. Figure 8 , Figure 9 The results obtained by the method in this embodiment are respectively Axial back potential and traditional methods Comparing the shaft back EMF with the actual back EMF of the motor, at the beginning of each control cycle, the back EMF obtained by this embodiment is almost equal to the actual back EMF of the motor, while the back EMF obtained by the traditional method has a large deviation.

[0072] In step S4 of this embodiment, the first Start of the cycle Back EMF estimate of the shaft , Obtain the first... through a phase-locked loop (PLL) Rotor position angle for period estimation and the electric angular velocity of the motor include:

[0073] S4.1, according to the first Start of the cycle Back EMF estimate of the shaft , Calculate the actual rotor position angle and the first Rotor position angle for period estimation The difference ;

[0074] S4.2, based on the actual rotor position angle and the estimated rotor position angle The difference For the Electric angular velocity of motor estimated by period After making corrections, the first Electric angular velocity of motor estimated by period ;

[0075] S4.3, will the first Electric angular velocity of motor estimated by period The first angle is obtained by accumulating the angles using the integrator. Rotor position angle for period estimation .

[0076] The solution The shaft back EMF is input to the phase-locked loop (PLL). In the k-th control cycle, to address the issue that the PLL feedback angle, being the angle estimated in the previous cycle, causes the final estimated angle to be one cycle ahead, the following applies: The solution has not yet been obtained, but we will choose to use it here. By directly adding a control cycle angle to the phase-locked loop feedback angle, This is to address the issue of leading angle estimation in the k-th period. cycle Back potential estimate , and the actual rotor position angle of the motor in the kth cycle The relationship is as follows:

[0077] ,

[0078] in, and The first cycle The estimated value of the back EMF of the shaft. For the first cycle The magnitude of the back EMF estimate.

[0079] By performing angle compensation on the phase-locked loop feedback angle for one control cycle, the estimated rotor position angle for the k-th cycle can be approximately obtained as follows:

[0080] ,

[0081] in, and The first Period and the Rotor position angle estimated over -1 cycle. For the first The electric angular velocity of the motor is estimated by period. To control the cycle.

[0082] In step S4.1 of this embodiment, according to the first Start of the cycle Back EMF estimate of the shaft , Calculate the actual rotor position angle and the first Rotor position angle for period estimation The difference The function expression is:

[0083] ,

[0084] in, and The first Start of the cycle The estimated value of the back EMF of the shaft. For the first Rotor position angle for period estimation For the first The electric angular velocity of the motor is estimated by period. To control the cycle. And we have:

[0085] ,

[0086] ,

[0087] in, For the first cycle The magnitude of the back EMF estimate.

[0088] In step S4.2 of this embodiment, the actual rotor position angle and the estimated rotor position angle are compared... The difference For the Electric angular velocity of motor estimated by period After making corrections, the first Electric angular velocity of motor estimated by period The function expression is:

[0089] ,

[0090] in, For the first The correction amount for estimating the electric angular velocity in the -1 cycle, and the first cycle... Correction amount for periodic estimation of electric angular velocity To compare the actual rotor position angle with the estimated rotor position angle The difference The result is obtained after inputting into the PI controller. Figure 10 In the middle, the estimated start time of the kth period is... The shaft back EMF is input to the phase-locked loop, and the angle is fed back by one control cycle through the (k-1)th cycle feedback angle. This yields a more accurate deviation signal, which then passes sequentially through a PI controller and an integrator. The estimated rotor position angle is obtained. For example... Figure 10 As shown, based on the direction of the arrow, it can be seen that in the k-th control cycle, the value to be estimated is... It needs to be solved first. Then After PI and integrator Estimated The role of the PI controller here is in the (k-1)th cycle. Based on the revision Thus, the k-th period is obtained. .Then Then input the integrator In this embodiment, the estimated angle is obtained based on the estimated angle of period k-1, and the estimated angle value of period k is obtained by accumulating the angles. This method mainly compensates for... The solution value, due to the estimation of the k-th period The exact angle is still unknown, but it is needed in advance. Therefore, the method in this embodiment uses phase-locked loop feedback angle compensation to approximately solve for the k-th period. ( Then, the actual rotor position of the motor in the k-th cycle is determined. Rotor position approximated by the k-th period Difference obtained This improves The solution accuracy (traditional methods do not perform compensation and directly feed back in the phase-locked loop) is high. ). Here through After approximate compensation, the following is obtained When the motor speed changes or there is an error in the estimated speed, approximate compensation will inevitably have a deviation, that is... Then The input is to the PI controller. Firstly, from the previous formula, we know: 1. If the compensated value ,Right now The correction amount output by the PI controller in the kth cycle. That is, the output of the PI controller The integrator increases the angle compared to the estimated angle obtained without correcting the estimated electric angular velocity. Output angle There will be an increase. 2. If the compensated value ,Right now The correction amount output by the PI controller in the kth cycle. That is, the output of the PI controller The integrator decreases in value compared to the estimated angle obtained without correcting the estimated electric angular velocity. Output angle It will decrease. Figure 11 This is the overall control block diagram for the rotor position estimation accuracy optimization method of this embodiment. This embodiment uses... The dual-closed-loop control framework calculates the start time of the k-th control cycle. Voltage estimate of the shaft , Sampling number k The current value at the start of the cycle, and based on The differential solution method for the axis current expression, using an observer to solve for the first... k Start of the cycle The back EMF of the shaft is used to extract and estimate a more accurate electric angular velocity and rotor position from the back EMF using an improved phase-locked loop. The calculated values ​​are then fed back to the dual closed-loop control system to achieve sensorless control of the high-speed permanent magnet motor. Figure 12 , Figure 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 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.

[0091] In summary, this embodiment adopts... The high-speed permanent magnet motor is controlled using a dual closed-loop control strategy. At the beginning of the k-th cycle, based on the k-1 and k-2 cycles... The output voltage of the shaft is calculated to determine the start time of the k-th cycle. The voltage across the shaft; ignoring the error of the current sampling circuit, the voltage is sampled and calculated at the beginning of this cycle. The shaft current is an accurate value, which ensures... The voltage and current of the shaft are the values ​​at the same moment during the motor's operation; compared to the traditional method of directly using the k-1 cycle. The method of shaft output voltage, for Optimizing the axis voltage before inputting it into the back EMF observer can improve the accuracy of back EMF estimation. Based on The current expression in the coordinate system can be directly derived by differentiating and substituting equations to obtain the differential current result. Compared to the traditional differential solution method, this method avoids introducing noise signals into the system, effectively reducing the discrete error of the current differential term under high-speed, low-carrier-ratio conditions, and ultimately improving the estimation accuracy of the back EMF. Based on the solved back EMF, it is input into the phase-locked loop (PLL) after feedback angle compensation to estimate the rotor position angle. In the k-th control cycle, the angle deviation input of the PI controller is the difference between the actual rotor position and the estimated rotor position in the k-th cycle. This makes the final output estimated rotor position extremely close to the actual rotor position. Therefore, this compensation method solves the problem of estimated angle lead caused by the delay of the PLL digital control, improving the accuracy of the PLL angle estimation.

[0092] Furthermore, this embodiment also provides a high-speed permanent magnet motor rotor position estimation accuracy optimization system, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method.

[0093] Furthermore, this embodiment also provides a computer-readable storage medium storing a computer program or instructions that are programmed or configured to execute the high-speed permanent magnet motor rotor position estimation accuracy optimization method via a processor.

[0094] 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 by a processor.

[0095] Those skilled in the art will understand that the technical solutions provided by the embodiments of this application may be in the form of a method, system, or computer program product. Therefore, this application may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application may take the form of a computer program product embodied on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create an implementation for the process. Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0096] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for optimizing the precision of rotor position estimation in high-speed permanent magnet machines, characterized by, comprising the steps of: S1, obtaining the first period, the first period voltage value of the second axis , and , the first period start time voltage estimation value of the second axis , ; S2, the first derivative of the current is obtained Period start time First derivative of the shaft current S3, according to the first Period start time Voltage estimate value of the axis , And the first derivative of the current, using the back EMF observer to obtain the second Period start time Back EMF estimate value of the axis , : ； wherein and are the stator currents of the motor in the d and q axis respectively, the beginning of the period an estimate of the back emf of the axis, and are the stator voltages of the motor in the d and q axis respectively, the beginning of the period an estimate of the voltage of the axis, denotes the stator resistance of the motor, and are the stator currents of the motor in the d and q axis respectively, the beginning of the period the stator currents, is the estimated electrical angular speed of the motor in the period , , denote the d and q axis inductances of the motor respectively; and are the stator currents of the motor in the d and q axis respectively, the beginning of the period the first derivative of the stator currents. S4, according to the first period anti-potential estimate of the shaft , by a phase-locked loop PLL to obtain the first period-estimated rotor position angle and the motor electrical angular velocity ; The average value equivalent principle of SVPWM is used to calculate the first Period start time Voltage estimation value of the axis , The function expression is: ， ， wherein and are the first the start of the period an estimate of the axis voltage, and are the first the output of the axis voltage for the -1 period an estimate of the axis voltage, and are the first the output of the axis voltage for the -2 period an estimate of the axis voltage.

2. The method for optimizing the precision of the rotor position estimation of a high-speed permanent-magnet motor according to claim 1, characterized in that, The current differential method is used in step S2 to obtain the first derivative of the axis current Period start time Axis voltage estimate , The function expression of the first derivative of the axis current at the same time is: The function expression of the first derivative of the axis current at the same time is: ， wherein and are the first the beginning of the period the first derivative of the shaft current, are the first the electrical angular velocity of the electric machine estimated for the period, and are the first the beginning of the period the shaft current, are the first the electrical angular velocity of the electric machine estimated for the period.

3. The method of claim 1, wherein, In step S4, the first Period start time Counter EMF estimate value of the shaft , The first Period estimated rotor position angle And motor electrical angular velocity Include: S4.1, according to the first Period start time Counter EMF estimate value of the shaft , Calculate the difference between the actual rotor position angle and the rotor position angle estimated by the first Period estimation ;​ S4.2, correcting the estimated motor electrical angular velocity of the first period according to the difference between the actual rotor position angle and the estimated rotor position angle ;​​​​​ S4.3, the first periodically estimated electrical angular velocity of the electrical machine the first periodically estimated rotor position angle .

4. The method for optimizing the precision of the rotor position estimation of a high-speed permanent-magnet motor according to claim 3, characterized in that, In step S4.1, according to the first Start of the cycle Back EMF estimate of the shaft , Calculate the actual rotor position angle and the first Rotor position angle for period estimation The difference The function expression is: ， wherein and are the first the start of the period an estimate of the back EMF of the shaft, the first the estimated rotor position angle of the period, the first the estimated electrical angular velocity of the motor of the period, the control period.

5. The method for optimizing the precision of the rotor position estimation of a high-speed permanent-magnet motor according to claim 4, characterized in that, Step S4.2: Correcting the estimated electrical angular velocity of the motor in the first period according to the difference between the actual rotor position angle and the estimated rotor position angle Step S4.3: Correcting the estimated electrical angular velocity of the motor in the first period according to the difference between the actual rotor position angle and the estimated rotor position angle Step S4.4: Correcting the estimated electrical angular velocity of the motor in the first period according to the difference between the actual rotor position angle and the estimated rotor position angle The function expression of the estimated electrical angular velocity of the motor in the first period is:​​​ ， wherein, is the first is the second is the first is the second is the difference between the actual rotor position angle and the estimated rotor position angle is obtained after inputting the PI controller.

6. 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 perform the high-speed permanent magnet motor rotor position estimation precision optimization method of any one of claims 1-5.

7. A computer-readable storage medium having stored therein a computer program or instructions, characterized in that, The computer program or instructions are programmed or configured to perform the high-speed permanent magnet motor rotor position estimation precision optimization method of any one of claims 1-5 by the processor.

8. A computer program product comprising computer programs or instructions, characterized in that, The computer program or instructions are programmed or configured to perform the high-speed permanent magnet motor rotor position estimation precision optimization method of any one of claims 1-5 by the processor. The computer program or instructions are programmed or configured to perform the high-speed permanent magnet motor rotor position estimation precision optimization method of any one of claims 1-5 by the processor.

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