Permanent magnet synchronous motor rotor position information acquisition method and device and control method and device

Abstract

The invention discloses a permanent magnet synchronous motor rotor position information acquisition method and device, and a control method and device, relates to a permanent magnet synchronous motor sensorless control technology, and aims to solve the problem of low accuracy of electrical angle and rotating speed estimation of an existing effective flux linkage method. The permanent magnet synchronous motor rotor position information acquisition method comprises the following steps: acquiring voltage and current data of a permanent magnet synchronous motor; correcting a calculation result of the voltage model by using a current model to obtain an effective flux linkage; filtering the effective flux linkage by using a second-order adaptive band-pass filter; and extracting a rotor electrical angle and a rotating speed from a filtering result by using a speed observer. The permanent magnet synchronous motor control method comprises the following steps: subtracting an estimated rotating speed from a given rotating speed and carrying out PI adjustment to obtain a reference current; the difference between the current feedback and the reference current is obtained, a PI regulator is used, and pre-modulated voltage is obtained; and obtaining a motor end voltage vector for the pre-modulated voltage, and controlling the permanent magnet synchronous motor.

Description

Technical Field

[0001] The present invention relates to the sensorless control technology of permanent magnet synchronous motors, and particularly to a method and device for obtaining rotor position information of permanent magnet synchronous motors, and a control method and device. Background Art

[0002] Permanent Magnet Synchronous Motors (PMSMs) have been widely used due to their advantages such as high efficiency, high reliability, simple control, constant torque below the base speed, and good dynamic performance. The rotor electrical angle of a permanent magnet synchronous motor is usually obtained using a resolver or an optical encoder. Generally, both of these position sensors can accurately obtain the rotor position. However, in a harsh environment, the reliability of the position sensor will be greatly reduced, and even a working failure may occur. In addition, the position sensor will also increase the system volume and cost. Therefore, researching the sensorless control technology of permanent magnet synchronous motors has great theoretical and practical significance.

[0003] In traditional methods, the sensorless control technology of permanent magnet synchronous motors can construct a flux observer by means of a motor voltage model or a current model to obtain an effective flux containing rotor position information, and then obtain the rotor electrical angle and speed. However, due to problems such as the non-linearity of the inverter, certain harmonic components will be mixed into the effective flux signal, which will affect the accuracy of flux calculation, and even cause the model to diverge, seriously affecting the accuracy of electrical angle and speed estimation, and reducing the control performance of the permanent magnet synchronous motor. Summary of the Invention

[0004] The purpose of this application is to solve or alleviate the above problems, and provide a method and device for obtaining rotor position information of a permanent magnet synchronous motor, and a control method and device.

[0005] According to one aspect of the embodiments of this application, a method for obtaining rotor position information of a permanent magnet synchronous motor is provided, including: obtaining voltage and current data of the permanent magnet synchronous motor; according to the voltage and current data, calculating the air-gap flux in the stationary coordinate system using a current model, correcting the air-gap flux calculated by the voltage model according to the air-gap flux, and obtaining an effective flux according to the corrected air-gap flux; filtering the effective flux using a second-order adaptive band-pass filter, and the center frequency of the second-order adaptive band-pass filter is the speed estimated at the previous moment; using a speed observer to extract the rotor electrical angle and speed from the output data of the second-order adaptive band-pass filter, and the rotor electrical angle and speed are the rotor electrical angle and speed estimated at the current moment.

[0006] Optionally, the voltage and current data include the current and voltage of the permanent magnet synchronous motor in the stationary coordinate system, and the current in the synchronous rotating coordinate system.

[0007] Optionally, the method for obtaining the current of the permanent magnet synchronous motor in the stationary coordinate system includes: collecting the three-phase current of the permanent magnet synchronous motor; and performing Clark transformation on the three-phase current to obtain the current in the stationary coordinate system.

[0008] Optionally, the method for obtaining the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system includes: performing Park transformation on the current in the stationary coordinate system to obtain the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system.

[0009] Optionally, the method for calculating the air-gap magnetic flux in the stationary coordinate system using the current model includes: calculating the air-gap magnetic flux in the stationary coordinate system using the current model according to the current in the synchronous rotating coordinate system.

[0010] Optionally, the method for correcting the air-gap magnetic flux calculated by the voltage model according to the air-gap magnetic flux and obtaining the effective magnetic flux according to the corrected air-gap magnetic flux includes: correcting the air-gap magnetic flux calculated by the voltage model according to the air-gap magnetic flux, in combination with the current and voltage in the stationary coordinate system, to obtain the effective magnetic flux.

[0011] According to another aspect of the embodiments of the present application, a control method for a permanent magnet synchronous motor based on the above method is provided, including: subtracting the estimated rotational speed from the given rotational speed, inputting the difference into a first PI regulator to obtain a reference current; subtracting the current feedback obtained according to the current data from the reference current, inputting the two differences into a second PI regulator and a third PI regulator respectively to obtain a pre-modulated voltage; performing space vector pulse width modulation on the pre-modulated voltage to obtain a modulated signal; obtaining a motor terminal voltage vector according to the modulated signal, and performing vector control on the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

[0012] According to still another aspect of the embodiments of the present application, a device for obtaining the rotor position information of a permanent magnet synchronous motor is provided, including: a data acquisition unit adapted to acquire voltage and current data of the permanent magnet synchronous motor; a voltage-current hybrid model calculation unit adapted to calculate the air-gap magnetic flux in the stationary coordinate system using the current model according to the voltage and current data, correct the air-gap magnetic flux calculated by the voltage model according to the air-gap magnetic flux, and obtain the effective magnetic flux according to the corrected air-gap magnetic flux; a filtering unit adapted to filter the effective magnetic flux using a second-order adaptive band-pass filter, the center frequency of the second-order adaptive band-pass filter being the rotational speed estimated at the previous moment; and an information extraction unit adapted to extract the rotor electrical angle and rotational speed from the output data of the second-order adaptive band-pass filter using a speed observer, the rotor electrical angle and rotational speed being the rotor electrical angle and rotational speed estimated at the current moment.

[0013] According to another aspect of the embodiments of the present application, a permanent magnet synchronous motor control device is provided, including: a reference current acquisition unit, adapted to subtract the estimated rotational speed from the given rotational speed, input the difference into a first PI regulator, and obtain a reference current; a pre-modulation voltage acquisition unit, adapted to subtract the current feedback obtained according to the current data from the reference current, input the two differences into a second PI regulator and a third PI regulator respectively, and obtain a pre-modulation voltage; a space vector pulse width modulation unit, adapted to perform space vector pulse width modulation on the pre-modulation voltage to obtain a modulated signal; and a control unit, adapted to obtain a motor terminal voltage vector according to the modulated signal, and perform vector control on the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

[0014] According to another aspect of the embodiments of the present application, a permanent magnet synchronous motor control system is provided, including: a current sampling module, configured to collect three-phase currents of a permanent magnet synchronous motor; a microcontroller, connected to the current sampling module, configured to process the data collected by the current sampling module to obtain an inverter control signal; and an inverter, connected to the microcontroller, configured to operate under the control of the inverter control signal output by the microcontroller to achieve control of the permanent magnet synchronous motor.

[0015] The method and device for obtaining rotor position information of a permanent magnet synchronous motor and the control method and device of the present invention obtain a high-precision air-gap magnetic flux through a voltage-current hybrid model, use a second-order adaptive band-pass filter whose center frequency can adaptively change with the estimated rotational speed to filter out harmonic disturbances in the effective magnetic flux, avoid problems of phase delay and amplitude attenuation, and estimate the rotor electrical angle and rotor speed with higher accuracy according to the output of the second-order adaptive band-pass filter. The present application can solve the problem of poor rotor angle and estimation accuracy caused by problems such as inverter nonlinearity, thereby effectively improving the sensorless control performance of the permanent magnet synchronous motor. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of a permanent magnet synchronous motor control system according to an embodiment of the present application;

[0017] Figure 2 is a schematic principle diagram of a permanent magnet synchronous motor control system according to an embodiment of the present application;

[0018] Figure 3 is a schematic flowchart of a method for obtaining rotor position information of a permanent magnet synchronous motor according to an embodiment of the present application;

[0019] Figure 4It is a comparison chart of the rotational speed error obtained by the permanent magnet synchronous motor rotor position information acquisition method of the embodiment of the present application and the traditional effective flux linkage method. Among them, (a) is the relationship between the rotational speed error obtained by the permanent magnet synchronous motor rotor position information acquisition method of the embodiment of the present application and time, and (b) is the relationship between the rotational speed error obtained by the traditional effective flux linkage method and time;

[0020] Figure 5 It is a comparison chart of the angle error obtained by the permanent magnet synchronous motor rotor position information acquisition method of the embodiment of the present application and the traditional effective flux linkage method. Among them, (a) is the relationship between the angle error obtained by the permanent magnet synchronous motor rotor position information acquisition method of the embodiment of the present application and time, and (b) is the relationship between the angle error obtained by the traditional effective flux linkage method and time;

[0021] Figure 6 It is a schematic flowchart of the permanent magnet synchronous motor control method according to the embodiment of the present application;

[0022] Figure 7 It is a schematic structural diagram of the permanent magnet synchronous motor rotor position information acquisition device according to the embodiment of the present application;

[0023] Figure 8 It is a schematic structural diagram of the permanent magnet synchronous motor control device according to the embodiment of the present application. Detailed implementation manners

[0024] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0025] As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should be further understood that the terms "comprising", "including" indicate the presence of the stated features, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, appearance or addition of one or more other features, operations, elements, components, items, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or meaning any one or any combination. Thus, "A, B or C" or "A, B and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B and C". Exceptions to this definition will occur only when the combination of elements, functions or operations are mutually exclusive in some way.

[0026] In view of the problems of the existing sensorless control technology for permanent magnet synchronous motors, the present invention provides a method and device for obtaining rotor position information of a permanent magnet synchronous motor, a control method and device for a permanent magnet synchronous motor based on this method, and a control system for a permanent magnet synchronous motor based on this method, which can filter out harmonic disturbances in the effective flux linkage signal, improve the accuracy of rotor position estimation, and further improve the performance of the permanent magnet synchronous motor control system.

[0027] Figure 1 FIG. is a schematic structural diagram of a permanent magnet synchronous motor control system according to an embodiment of the present application. As Figure 1 shown, the permanent magnet synchronous motor control system 100 mainly includes a microcontroller 120, an inverter 130, and a current sampling module 140. Among them, the inverter 130 is a three-phase full-bridge inverter. The current sampling module 140 is used to collect the three-phase currents of the permanent magnet synchronous motor 110 and send the collected currents to the microcontroller 120. Figure 2 FIG. is a schematic principle diagram of a permanent magnet synchronous motor control system according to an embodiment of the present application. In the permanent magnet synchronous motor control system, the microcontroller 120 undertakes the calculation function. As Figure 2 shown, the microcontroller 120 internally embeds functional modules such as Clark and Park transformations, voltage-current hybrid models, second-order adaptive band-pass filters, speed observers, IP regulation, and Space Vector Pulse Width Modulation (SVPWM) implemented by software. The microcontroller 120 processes and calculates the three-phase currents of the permanent magnet synchronous motor 110 to obtain an inverter control signal, and this inverter control signal is used to control the power devices of the inverter 130. The inverter 130 operates under the action of the above inverter control signal to achieve the control of the permanent magnet synchronous motor 110.

[0028] In the embodiment of the present application, the microcontroller 120 is configured to implement a method for obtaining rotor position information of a permanent magnet synchronous motor and a control method for a permanent magnet synchronous motor.

[0029] The method for obtaining rotor position information of a permanent magnet synchronous motor in the embodiment of the present application includes: obtaining voltage and current data of the permanent magnet synchronous motor; according to the voltage and current data, calculating the air-gap flux linkage in the stationary coordinate system using a current model, correcting the air-gap flux linkage calculated by the voltage model according to the air-gap flux linkage, and obtaining an effective flux linkage according to the corrected air-gap flux linkage; filtering the effective flux linkage using a second-order adaptive band-pass filter, and the center frequency of the second-order adaptive band-pass filter is the rotational speed estimated at the previous moment; using a speed observer to extract the rotor electrical angle and rotational speed from the output data of the second-order adaptive band-pass filter, and the rotor electrical angle and rotational speed are the rotor electrical angle and rotational speed estimated at the current moment.

[0030] Figure 3 is a schematic flowchart of a method 300 for obtaining the rotor position information of a permanent magnet synchronous motor according to an embodiment of the present application. As Figure 3 shown, in a sampling period, the method 300 for obtaining the rotor position information of the permanent magnet synchronous motor starts from step S310.

[0031] In step S310, the voltage and current data of the permanent magnet synchronous motor 110 are obtained.

[0032] In an embodiment of the present application, the current sampling module samples the three-phase current of the permanent magnet synchronous motor 110 according to a set sampling frequency, and inputs the collected current data into the microcontroller 120 for processing.

[0033] The voltage and current data of the permanent magnet synchronous motor 110 refer to the voltage data and current data required in the calculation of the voltage model and the current model. Specifically, the current data includes the current of the permanent magnet synchronous motor 110 in the stationary coordinate system and the current in the synchronous rotating coordinate system, and the voltage data includes the voltage of the permanent magnet synchronous motor 110 in the stationary coordinate system.

[0034] In one implementation, the method for obtaining the above current data includes:

[0035] Collect the three-phase current of the permanent magnet synchronous motor 110. Here, the three-phase current of the permanent magnet synchronous motor 110 collected at time k (i.e., the current moment) is defined as i a 、i b 、i c ;

[0036] Perform Clark transformation on i a 、i b 、i c according to formula (1) to convert i a 、i b 、i c into the current i α 、i β under the αβ axis of the stationary coordinate system;

[0037]

[0038] Perform Park transformation on i α 、i β according to formula (2) to obtain the current i d 、i q of the permanent magnet synchronous motor 110 under the dq axis of the synchronous rotating coordinate system.

[0039]

[0040] Among them, is the rotor electrical angle at time k predicted in the sampling period at time k - 1 (the previous sampling period).

[0041] The voltage data can be obtained by collecting the input voltage of SVPWM. The input voltage of SVPWM is equivalent to the voltage of the permanent magnet synchronous motor 110 in the stationary coordinate system, and this voltage is also called the pre-modulation voltage.

[0042] Next, in step S320, according to the voltage and current data, the air-gap flux linkage in the stationary coordinate system is calculated using the current model. The air-gap flux linkage calculated by the voltage model is corrected based on the air-gap flux linkage, and the effective flux linkage is obtained based on the corrected air-gap flux linkage.

[0043] In this step, the air-gap flux linkage in the αβ axes of the stationary coordinate system is first calculated according to the current model:

[0044]

[0045] Among them, ψ cα , ψ cβ represent the air-gap flux linkage in the αβ axes of the stationary coordinate system calculated by the current model, L s represents the synchronous inductance of the motor, ψ f represents the permanent magnet flux linkage, L s and ψ f are both known quantities.

[0046] Next, the voltage-current hybrid model is used to calculate the air-gap flux linkage. The voltage-current hybrid model corrects the air-gap flux linkage calculated by the voltage model with ψ cα , ψ cβ as a reference. The calculation formula is expressed as:

[0047]

[0048] Among them, k p , k i are adjustable parameters, R s is the known phase resistance of the motor, ψ sα (k), ψ sβ (k) represent the corrected air-gap flux linkage of the voltage model in the αβ axes of the stationary coordinate system at time k, ψ sα (k + 1), ψ sβ (k + 1) represent the corrected air-gap flux linkage in the αβ axes of the stationary coordinate system at time k + 1 predicted at time k, and this value will be used for the calculation of the effective flux linkage in the next sampling period.

[0049] Next, the effective flux linkage ψ actα and ψ actβ are calculated according to the corrected air-gap flux linkage in the αβ axes of the stationary coordinate system predicted at time k:

[0050] [ψ actα ψ actβ T =[ψ sα (k)ψ sβ (k)] T -L s [i α i β T (5)

[0051] The voltage model of the permanent magnet synchronous motor is greatly affected by the stator resistance. At low speeds, the back electromotive force obtained is low, the stator resistance voltage drop ratio is large, and the resistance value will change due to different environments. Therefore, the accuracy of the air-gap magnetic flux calculated by the voltage model at low speeds is insufficient, while the accuracy of the air-gap magnetic flux calculated by the voltage model at high speeds is relatively high. The current model is not affected by the stator resistance and uses the estimated angle for real-time calculation. Therefore, the accuracy of the air-gap magnetic flux calculated by the current model at low speeds is higher. However, the current model is easily affected by inductance and permanent magnets and has poor robustness. According to formula (4), the voltage-current hybrid model combines the characteristics of the voltage model and the current model, and with the adjustment of the two parameters k p 、k i , the obtained air-gap magnetic flux value can be made close to 0.

[0052] Next, in step S330, a second-order adaptive band-pass filter is used to filter the effective magnetic flux, and the center frequency of the second-order adaptive band-pass filter is the rotational speed estimated at the previous moment.

[0053] In this step, a second-order adaptive band-pass filter is used to filter the effective magnetic flux obtained in the previous step to filter out non-ideal harmonic interference.

[0054] The transfer function of the second-order adaptive band-pass filter in the embodiment of the present application is:

[0055]

[0056] where ω B is the bandwidth of the second-order adaptive band-pass filter, ω0 is the center frequency of the second-order adaptive band-pass filter, and s represents the Laplace operator.

[0057] The formula of the above second-order adaptive band-pass filter is:

[0058]

[0059] where T s ​​Let \(T_s\) be the sampling period, \(y(k)\) be the output of the second - order adaptive band - pass filter at time \(k\), \(y(k - 1)\) be the output of the second - order adaptive band - pass filter at time \(k-1\), \(y(k - 2)\) be the output of the second - order adaptive band - pass filter at time \(k - 2\), \(x(k)\) be the input of the second - order adaptive band - pass filter at time \(k\), \(x(k - 1)\) be the input of the second - order adaptive band - pass filter at time \(k-1\). In the embodiment of the present application, \(x(k)=\psi\). actα and \(\psi\) actβ .

[0060] The center frequency \(\omega_0\) of the above - mentioned second - order adaptive band - pass filter is not fixed, but adapts to the change of the estimated rotational speed, so as to avoid the problems of phase delay or amplitude attenuation. Its value is:

[0061] \(\omega_0=\omega\) k (8)

[0062] where \(\omega\) k is the rotational speed in the current sampling period \(T_s\) predicted by the speed observer at time \(k - 1\) through step S340.

[0063] This step uses the filtering function and low - delay characteristics of the second - order adaptive band - pass filter to filter the effective magnetic flux, and avoids the problems of delay and amplitude attenuation through the adaptive characteristic of the center frequency of the second - order adaptive band - pass filter.

[0064] Next, in step S340, a speed observer is used to extract the rotor electrical angle and rotational speed from the output data of the second - order adaptive band - pass filter. The rotor electrical angle and rotational speed are the rotor electrical angle and rotational speed estimated at the current moment for the next moment.

[0065] The filtered effective magnetic flux contains the rotor electrical angle information of the next sampling period predicted at the current moment (i.e., time \(k\)), and its calculation formula is:

[0066]

[0067] \(\varPhi\) represents the value of the filtered effective magnetic flux (the output of the second - order adaptive band - pass filter).

[0068] Then, extract the rotor rotational speed information of the motor:

[0069]

[0070] where and

[0071] respectively represent the rotor electrical angles at times \(k\) and \(k + 1\) calculated by the speed observer. and \(\omega\)k+1 is the rotor electrical angle and speed in the sampling period at the (k + 1)-th moment estimated by the speed observer for the sampling period at the k-th moment, and β1, β2 are the gain coefficients of the speed observer.

[0072] In the method for obtaining the rotor position information of the permanent magnet synchronous motor according to the embodiment of the present application, since a voltage-current hybrid model and a filter with an adaptive feature are adopted, the accuracy of the rotor electrical angle and speed estimated by the speed observer is improved. As Figure 4 shown, the speed error obtained by the traditional effective flux linkage method is in the range of (-0.5, 0.5) rpm, while the speed error obtained by the method for obtaining the rotor position information of the permanent magnet synchronous motor of the present application is close to 0. As Figure 5 shown, the angle error obtained by the traditional effective flux linkage method is in the range of (-0.5, 0.025) rad, while the angle error obtained by the method for obtaining the rotor position information of the permanent magnet synchronous motor of the present application is also close to 0.

[0073] The embodiment of the present application also provides a control method for a permanent magnet synchronous motor based on the above method for obtaining the rotor position information of the permanent magnet synchronous motor. The control method for the permanent magnet synchronous motor includes: subtracting the estimated speed from the given speed, inputting the difference into a first PI regulator to obtain a reference current; subtracting the current feedback obtained according to the current data from the reference current, inputting the two differences into a second PI regulator and a third PI regulator respectively to obtain a pre-modulated voltage; performing space vector pulse width modulation on the pre-modulated voltage to obtain a modulated signal; obtaining a motor terminal voltage vector according to the modulated signal, and controlling the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

[0074] Figure 6 is a schematic flowchart of a control method 600 for a permanent magnet synchronous motor according to an embodiment of the present application. The method 600 can be implemented based on Figure 2 the principle shown. As Figure 6 shown, the method 600 starts at step S610.

[0075] In step S610, the estimated speed is subtracted from the given speed, and the difference is input into a first PI regulator 121 to obtain a reference current.

[0076] As Figure 2 shown, the speed ω k estimated by the speed observer in the previous sampling period (the sampling period corresponding to the (k - 1)-th moment) is * subtracted from the given speed ω, and the difference is input into the first PI regulator 121 for PI regulation. The first PI regulator 121 outputs a reference current i q * .

[0077] Next, in step S620, the current feedback obtained from the current data is subtracted from the reference current, and the two differences are respectively input into the second PI regulator 122 and the third PI regulator 123 to obtain the pre-modulation voltage.

[0078] The currents i a , i b , i c collected by the current acquisition module are subjected to Clark transformation and Park transformation to obtain the current feedbacks i d , i q . The difference between i d and i q is respectively subtracted from the reference currents i d * and i q * . In the embodiment of the present application, i d * = 0. The difference between i q and i q * is input into the second PI regulator 122, and the difference between i d and i d * is input into the third PI regulator 123. The outputs of the second PI regulator 122 and the third PI regulator 123 are subjected to Park -1 transformation to obtain the pre-modulation voltages u α and u β .

[0079] Next, in step S630, space vector pulse width modulation is performed on the pre-modulation voltage to obtain the modulated signal.

[0080] In this step, SVPWM calculation is performed on the pre-modulation voltages u α and u β obtained in the previous step, and the pre-modulation voltages u α and u β are converted into duty cycle signals.

[0081] Next, in step S640, the motor terminal voltage vector is obtained according to the modulated signal, and the operation of the permanent magnet synchronous motor is vector-controlled according to the motor terminal voltage vector.

[0082] In this step, the on / off of the inverter power devices is controlled according to the duty cycle signal obtained in the previous step, so as to obtain the required motor terminal voltage vector, and the operation of the permanent magnet synchronous motor is controlled according to the motor terminal voltage vector.

[0083] The embodiment of the present application further provides a device for obtaining the rotor position information of a permanent magnet synchronous motor, which can implement the processing of each step of the above method for obtaining the rotor position information of a permanent magnet synchronous motor.

[0084] Figure 7 It is a schematic structural diagram of a device for obtaining rotor position information of a permanent magnet synchronous motor according to an embodiment of the present application. As Figure 7 shown, the device 700 for obtaining rotor position information of a permanent magnet synchronous motor includes a data acquisition unit 710, a voltage-current hybrid model calculation unit 720, a filtering unit 730, and an information extraction unit 740.

[0085] The data acquisition unit 710 acquires voltage and current data of the permanent magnet synchronous motor.

[0086] The voltage-current hybrid model calculation unit 720 is adapted to calculate the air-gap magnetic flux in the stationary coordinate system according to the voltage and current data by using a current model, correct the air-gap magnetic flux calculated by the voltage model according to the air-gap magnetic flux, and obtain the effective magnetic flux according to the corrected air-gap magnetic flux.

[0087] The filtering unit 730 is adapted to filter the effective magnetic flux by using a second-order adaptive band-pass filter, and the center frequency of the second-order adaptive band-pass filter is the rotational speed estimated at the previous moment; and

[0088] The information extraction unit 740 is adapted to extract the rotor electrical angle and rotational speed from the output data of the second-order adaptive band-pass filter by using a speed observer, and the rotor electrical angle and rotational speed are the rotor electrical angle and rotational speed estimated at the current moment.

[0089] As a preferred embodiment of the present application, the voltage and current data include the current and voltage of the permanent magnet synchronous motor in the stationary coordinate system, and the current in the synchronous rotating coordinate system.

[0090] As a preferred embodiment of the present application, the method for obtaining the current of the permanent magnet synchronous motor in the stationary coordinate system includes:

[0091] Collecting the three-phase current of the permanent magnet synchronous motor; and

[0092] Performing Clark transformation on the three-phase current to obtain the current in the stationary coordinate system.

[0093] As a preferred embodiment of the present application, the method for obtaining the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system includes:

[0094] Performing Park transformation on the current in the stationary coordinate system to obtain the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system.

[0095] As a preferred embodiment of the present application, the calculating the air-gap magnetic flux in the stationary coordinate system by using a current model includes:

[0096] Based on the current in the synchronous rotating coordinate system, the air-gap flux linkage in the stationary coordinate system is calculated using the current model.

[0097] As a preferred embodiment of the present application, the correction of the air-gap flux linkage calculated by the voltage model according to the air-gap flux linkage, and obtaining the effective flux linkage according to the corrected air-gap flux linkage includes:

[0098] According to the air-gap flux linkage, combining the current and voltage in the stationary coordinate system, the air-gap flux linkage calculated by the voltage model is corrected to obtain the effective flux linkage.

[0099] The permanent magnet synchronous motor rotor position information acquisition device 700 has the same principle and technical effect as the permanent magnet synchronous motor rotor position information acquisition method 300, and will not be elaborated here.

[0100] The embodiment of the present application also provides a permanent magnet synchronous motor control device, which can implement the processing of each step of the above permanent magnet synchronous motor control method.

[0101] Figure 8 It is a schematic structural diagram of the permanent magnet synchronous motor control device according to the embodiment of the present application. As Figure 8 shown, the permanent magnet synchronous motor control device 800 includes a reference current acquisition unit 810, a pre-modulated voltage acquisition unit 820, a space vector pulse width modulation unit 830, and a control unit 840.

[0102] The reference current acquisition unit 810 is adapted to subtract the estimated rotational speed from the given rotational speed, input the difference into the first PI regulator, and obtain the reference current.

[0103] The pre-modulated voltage acquisition unit 820 is adapted to subtract the current feedback obtained according to the current data from the reference current, input the two differences into the second PI regulator and the third PI regulator respectively, and obtain the pre-modulated voltage.

[0104] The space vector pulse width modulation unit 830 is adapted to perform space vector pulse width modulation on the pre-modulated voltage to obtain a modulated signal.

[0105] The control unit 840 is adapted to obtain the motor terminal voltage vector according to the modulated signal, and perform vector control on the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

[0106] The permanent magnet synchronous motor control device 800 has the same principle and technical effect as the permanent magnet synchronous motor control method 600, and will not be elaborated here.

[0107] The various techniques described herein can be implemented in conjunction with hardware or software, or a combination thereof. Thus, the methods and apparatuses of the present invention, or certain aspects or portions of the methods and apparatuses of the present invention, may take the form of program code (i.e., instructions) embedded in a tangible medium, such as a removable hard disk, a USB flash drive, a floppy disk, a CD-ROM, or any other machine-readable storage medium, wherein when the program is loaded into and executed by a machine such as a computer, the machine becomes an apparatus for practicing the present invention.

Claims

1. A method for obtaining rotor position information of a permanent magnet synchronous motor, characterized in that Comprising: Obtaining voltage and current data of a permanent magnet synchronous motor; According to the voltage and current data, calculating the air-gap flux linkage in the stationary coordinate system by using a current model, correcting the air-gap flux linkage calculated by the voltage model according to the air-gap flux linkage, and obtaining the effective flux linkage according to the corrected air-gap flux linkage; Filtering the effective flux linkage by using a second-order adaptive band-pass filter, wherein the center frequency of the second-order adaptive band-pass filter is the rotational speed estimated at the previous moment; Using a speed observer to extract the rotor electrical angle and rotational speed from the output data of the second-order adaptive band-pass filter, wherein the rotor electrical angle and rotational speed are the rotor electrical angle and rotational speed estimated at the current moment.

2. The method according to claim 1, characterized in that, The voltage and current data includes the current and voltage of the permanent magnet synchronous motor in the stationary coordinate system and the current in the synchronous rotating coordinate system.

3. The method according to claim 2, wherein The method for obtaining the current of the permanent magnet synchronous motor in the stationary coordinate system includes: Collecting the three-phase current of the permanent magnet synchronous motor; and Performing a Clark transformation on the three-phase current to obtain the current in the stationary coordinate system.

4. The method according to claim 2 or 3, characterized in that, The method for obtaining the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system includes: Performing a Park transformation on the current in the stationary coordinate system to obtain the current of the permanent magnet synchronous motor in the synchronous rotating coordinate system.

5. The method according to claim 2, characterized in that, The calculating the air-gap flux linkage in the stationary coordinate system by using the current model includes: Calculating the air-gap flux linkage in the stationary coordinate system by using the current model according to the current in the synchronous rotating coordinate system.

6. The method according to claim 5, wherein The correcting the air-gap flux linkage calculated by the voltage model according to the air-gap flux linkage and obtaining the effective flux linkage according to the corrected air-gap flux linkage includes: According to the air-gap flux linkage, combining the current and voltage in the stationary coordinate system, correcting the air-gap flux linkage calculated by the voltage model, and obtaining the effective flux linkage.

7. A permanent magnet synchronous motor control method based on the method according to any one of claims 1 to 6, characterized in that, Comprising: Subtracting the estimated rotational speed from the given rotational speed, inputting the difference into a first PI regulator to obtain a reference current; Subtracting the current feedback obtained according to the current data from the reference current, inputting the two differences into a second PI regulator and a third PI regulator respectively to obtain a pre-modulated voltage; Performing space vector pulse width modulation on the pre-modulated voltage to obtain a modulated signal; Obtaining a motor terminal voltage vector according to the modulated signal, and performing vector control on the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

8. A device for obtaining rotor position information of a permanent magnet synchronous motor, characterized in that, Comprising: A data acquisition unit adapted to obtain voltage and current data of a permanent magnet synchronous motor; A voltage-current hybrid model calculation unit adapted to calculate the air-gap flux linkage in the stationary coordinate system by using a current model according to the voltage and current data, correct the air-gap flux linkage calculated by the voltage model according to the air-gap flux linkage, and obtain the effective flux linkage according to the corrected air-gap flux linkage; A filtering unit adapted to filter the effective flux linkage by using a second-order adaptive band-pass filter, wherein the center frequency of the second-order adaptive band-pass filter is the rotational speed estimated at the previous moment; And An information extraction unit adapted to use a speed observer to extract the rotor electrical angle and rotational speed from the output data of the second-order adaptive band-pass filter, wherein the rotor electrical angle and rotational speed are the rotor electrical angle and rotational speed estimated at the current moment.

9. A permanent magnet synchronous motor control device, characterized in that, Comprising: A reference current acquisition unit, adapted to subtract the estimated rotational speed from the given rotational speed, input the difference into a first PI regulator, and obtain a reference current; A pre-modulation voltage acquisition unit, adapted to subtract the current feedback obtained according to the current data from the reference current, input the two differences into a second PI regulator and a third PI regulator respectively, and obtain a pre-modulation voltage; A space vector pulse width modulation unit, adapted to perform space vector pulse width modulation on the pre-modulation voltage to obtain a modulated signal; And A control unit, adapted to obtain a motor terminal voltage vector according to the modulated signal, and perform vector control on the operation of the permanent magnet synchronous motor according to the motor terminal voltage vector.

10. A permanent magnet synchronous motor control system, characterized in that, Comprising: A current sampling module, which samples the three-phase current of the permanent magnet synchronous motor; A microcontroller, connected to the current sampling module, processes the data collected by the current sampling module, and obtains an inverter control signal; An inverter, connected to the microcontroller, operates under the control of the inverter control signal output by the microcontroller to realize the control of the permanent magnet synchronous motor.

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