A control method and system of a sensorless motor

Abstract

The application provides a control method and system of a position sensorless motor, which is realized through a flux linkage observer, and comprises the following steps: a first flux linkage observation amplitude is determined by a flux linkage estimation module according to an output current, an output voltage and a historical disturbance estimation value of the motor; a first flux linkage disturbance estimation value and a quadrature axis flux linkage amplitude are determined by a disturbance estimation module according to the first flux linkage observation amplitude, a flux linkage given amplitude and a historical position electric angle, and the first flux linkage disturbance estimation value is fed back to the flux linkage estimation module; a target position electric angle of a rotor in a target motor is determined by a rotor angle estimation module according to the quadrature axis flux linkage amplitude, and the target position electric angle is fed back to the disturbance estimation module. In this way, the disturbance estimation module is constructed in the flux linkage observer, the flux linkage disturbance is estimated and the flux linkage observation amplitude is compensated, so that the accuracy of the determination result of the position electric angle of the rotor in the motor is improved.

Description

Technical Field

[0001] This application relates to the field of motor control technology, and in particular to a control method and system for a sensorless motor. Background Technology

[0002] Sensorless motor control schemes typically employ back-EMF observers or flux linkage observers to estimate the motor position, with flux linkage observers being widely used due to their superior low-speed performance. Active flux linkage observers, as a type of flux linkage observer, are compatible with many types of AC motors, including asynchronous motors, permanent magnet synchronous motors, and synchronous reluctance motors. Currently, most active flux linkage observers use voltage models to observe the active flux linkage. However, when directly using voltage models to observe the active flux linkage, factors such as motor parameter variations, integral drift, high-frequency noise, stator current measurement errors, and stator voltage errors caused by the nonlinearity of the inverter dead time can all lead to discrepancies between the observed and actual active flux linkage values. To address this issue, most current schemes use low-pass or band-pass filters to filter the observed flux linkage. However, such filtering itself distorts the effective signal, thus affecting the dynamic and steady-state performance of the motor control system. Another approach is to introduce a current model of the flux linkage to correct the voltage model of the flux linkage. However, the introduced current model is highly dependent on the parameters of the motor itself. This means that changes in the motor parameters will lead to inaccuracies in the current model, which in turn will result in inaccurate correction of the voltage model by the current model. Consequently, there will still be a deviation between the observed flux linkage and the actual flux linkage. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a control method and system for a sensorless motor. By constructing a disturbance estimation module inside the flux observer, the disturbance of flux can be estimated and compensated, thereby improving the accuracy of the determination of the rotor's position electrical angle in the motor.

[0004] This application provides a control method for a sensorless motor, implemented using a flux linkage observer. The flux linkage observer includes a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module. The control method includes:

[0005] The flux linkage estimation module performs compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment;

[0006] The disturbance estimation module determines the estimated value of the first flux disturbance and the cross-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment.

[0007] The rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude and through phase-locked loop processing; the target position electrical angle is used to output the control signal for controlling the target motor.

[0008] Optionally, the first output current and the first output voltage of the target motor are determined through the following steps:

[0009] Obtain all phase voltages and all phase currents output by the target motor at the current moment;

[0010] The target motor outputs all phase voltages and all phase currents by performing coordinate system transformation to determine the first output current and the first output voltage of the target motor at the current moment, and then inputs the first output current and the first output voltage to the flux linkage estimation module.

[0011] Optionally, the step of determining the first flux linkage observation amplitude at the current moment by the flux linkage estimation module through compensation processing based on the first output current and first output voltage of the target motor at the current moment, and the estimated historical disturbance value determined at the previous moment, includes:

[0012] Substitute the first output current and the first output voltage into the initial flux linkage equation preset in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment.

[0013] The initial flux linkage observation amplitude is compensated using the historical disturbance estimate to determine the first flux linkage observation amplitude.

[0014] Optionally, the step of determining the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment by the disturbance estimation module based on the first flux observed amplitude, the pre-acquired given flux amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment includes:

[0015] Based on the historical position electrical angle, the first magnetic flux observation amplitude is transformed using coordinate system transformation to determine the second magnetic flux observation amplitude at the current moment; wherein, the second magnetic flux observation amplitude includes the cross-axis magnetic flux amplitude;

[0016] The flux linkage error amplitude at the current moment is determined based on the difference between the observed amplitude of the second flux linkage and the given amplitude of the flux linkage.

[0017] The flux linkage error amplitude is input into the proportional-integral estimation formula pre-set in the disturbance estimation module to determine the estimated value of the second flux linkage disturbance at the current moment; wherein, the proportional-integral estimation formula is a formula that characterizes the mapping relationship between error and disturbance after introducing proportional gain and integral gain;

[0018] Based on the historical position electrical angle, the estimated value of the second magnetic flux disturbance is transformed using coordinate system transformation to determine the estimated value of the first magnetic flux disturbance.

[0019] Optionally, the step of determining the target position electrical angle of the rotor in the target motor at the current moment by the rotor angle estimation module based on the quadrature-axis flux linkage amplitude and through phase-locked loop processing includes:

[0020] The proportional-integral unit in the rotor angle estimation module determines the current electric angular velocity of the rotor in the target motor based on the cross-axis flux linkage amplitude.

[0021] The integral unit in the rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the electrical angular velocity.

[0022] Optionally, after determining the estimated value of the first flux disturbance at the current moment, the control method further includes:

[0023] The disturbance estimation module feeds back the first flux disturbance estimate to the flux estimation module so that the flux estimation module can update the historical disturbance estimate.

[0024] Optionally, after determining the target position electrical angle of the rotor in the target motor at the current moment, the control method further includes:

[0025] The rotor angle estimation module feeds back the target position electrical angle to the disturbance estimation module so that the disturbance estimation module can update the historical position electrical angle.

[0026] This application embodiment also provides a control system for a sensorless motor, the control system including a flux linkage observer, the flux linkage observer including a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module:

[0027] The flux linkage estimation module is used to perform compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment.

[0028] The disturbance estimation module is used to determine the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment.

[0029] The rotor angle estimation module is used to determine the target position electrical angle of the rotor in the target motor at the current moment based on the amplitude of the cross-axis flux linkage and through phase-locked loop processing; the target position electrical angle is used to output a control signal to control the target motor.

[0030] Optionally, the control system further includes a determining module, the determining module being used for:

[0031] Obtain all phase voltages and all phase currents output by the target motor at the current moment;

[0032] The target motor outputs all phase voltages and all phase currents by performing coordinate system transformation to determine the first output current and the first output voltage of the target motor at the current moment, and then inputs the first output current and the first output voltage to the flux linkage estimation module.

[0033] Optionally, when the flux linkage estimation module is used to determine the first flux linkage observation amplitude at the current moment based on the first output current and first output voltage of the target motor at the current moment and the estimated value of the historical disturbance determined at the previous moment, the flux linkage estimation module is used to:

[0034] Substitute the first output current and the first output voltage into the initial flux linkage equation preset in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment.

[0035] The initial flux linkage observation amplitude is compensated using the historical disturbance estimate to determine the first flux linkage observation amplitude.

[0036] Optionally, when the disturbance estimation module determines the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment, the disturbance estimation module is used to:

[0037] Based on the historical position electrical angle, the first magnetic flux observation amplitude is transformed using coordinate system transformation to determine the second magnetic flux observation amplitude at the current moment; wherein, the second magnetic flux observation amplitude includes the cross-axis magnetic flux amplitude;

[0038] The flux linkage error amplitude at the current moment is determined based on the difference between the observed amplitude of the second flux linkage and the given amplitude of the flux linkage.

[0039] The flux linkage error amplitude is input into the proportional-integral estimation formula pre-set in the disturbance estimation module to determine the estimated value of the second flux linkage disturbance at the current moment; wherein, the proportional-integral estimation formula is a formula that characterizes the mapping relationship between error and disturbance after introducing proportional gain and integral gain;

[0040] Based on the historical position electrical angle, the estimated value of the second magnetic flux disturbance is transformed using coordinate system transformation to determine the estimated value of the first magnetic flux disturbance.

[0041] Optionally, when the rotor angle estimation module is used to determine the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude and through phase-locked loop processing, the rotor angle estimation module is used to:

[0042] The proportional-integral unit in the rotor angle estimation module determines the current electric angular velocity of the rotor in the target motor based on the cross-axis flux linkage amplitude.

[0043] The integral unit in the rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the electrical angular velocity.

[0044] Optionally, the disturbance estimation module is further configured to:

[0045] The first flux linkage disturbance estimate is fed back to the flux linkage estimation module so that the flux linkage estimation module can update the historical disturbance estimate.

[0046] Optionally, the rotor angle estimation module is further used for:

[0047] The electrical angle of the target position is fed back to the disturbance estimation module so that the disturbance estimation module can update the historical position electrical angle.

[0048] This application also provides an electronic device, including: a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, the steps of the control method described above are performed.

[0049] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the control method described above.

[0050] This application provides a control method and system for a sensorless motor. The control method is implemented using a flux linkage observer, which includes a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module. The control method includes: the flux linkage estimation module performing compensation processing based on the first output current and first output voltage of the target motor at the current moment, and the historical disturbance estimation value determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment; the disturbance estimation module determining the first flux linkage disturbance estimation value and the quadrature-axis flux linkage amplitude at the current moment based on the first flux linkage observation amplitude, a pre-acquired flux linkage given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment; and the rotor angle estimation module determining the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude through a phase-locked loop; the target position electrical angle is used to output a control signal to control the target motor.

[0051] Thus, this application constructs a disturbance estimation module within the flux linkage observer. The observer itself estimates the flux linkage disturbance and compensates for the flux linkage observation amplitude, thereby eliminating the influence of factors such as parameter variations, integral drift, high-frequency noise, and measurement errors on the flux linkage observation values. This enhances the parameter robustness and disturbance resistance of the flux linkage observer, ultimately improving the accuracy of the rotor position electrical angle determination results in the motor.

[0052] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0053] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A flowchart illustrating a sensorless motor control method provided in this application embodiment;

[0055] Figure 2 A schematic diagram illustrating the principle of the flux linkage estimation module provided in this application;

[0056] Figure 3 Schematic diagrams of a stationary coordinate system and a synchronously rotating coordinate system;

[0057] Figure 4 A schematic diagram illustrating the principle of the disturbance estimation module provided in this application;

[0058] Figure 5 A schematic diagram illustrating the principle of the rotor angle estimation module provided in this application;

[0059] Figure 6 This is a schematic diagram of the internal workings of the magnetic flux observer provided in this application;

[0060] Figure 7 Block diagram of a sensorless motor magnetic field orientation vector control system;

[0061] Figure 8 This is a schematic diagram of the structure of a sensorless motor control system provided in an embodiment of this application;

[0062] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. Based on the embodiments of this application, every other embodiment obtained by those skilled in the art without inventive effort falls within the scope of protection of this application.

[0064] Sensorless motor control schemes typically employ back-EMF observers or flux linkage observers to estimate the motor position, with flux linkage observers being widely used due to their superior low-speed performance. Active flux linkage observers, as a type of flux linkage observer, are compatible with many types of AC motors, including asynchronous motors, permanent magnet synchronous motors, and synchronous reluctance motors. Currently, most active flux linkage observers use voltage models to observe the active flux linkage. However, when directly using voltage models to observe the active flux linkage, factors such as motor parameter variations, integral drift, high-frequency noise, stator current measurement errors, and stator voltage errors caused by the nonlinearity of the inverter dead time can all lead to discrepancies between the observed and actual active flux linkage values. To address this issue, most current schemes use low-pass or band-pass filters to filter the observed flux linkage. However, such filtering itself distorts the effective signal, thus affecting the dynamic and steady-state performance of the motor control system. Another approach is to introduce a current model of the flux linkage to correct the voltage model of the flux linkage. However, the introduced current model is highly dependent on the parameters of the motor itself. This means that changes in the motor parameters will lead to inaccuracies in the current model, which in turn will result in inaccurate correction of the voltage model by the current model. Consequently, there will still be a deviation between the observed flux linkage and the actual flux linkage.

[0065] Based on this, the embodiments of this application provide a control method and system for a sensorless motor. By constructing a disturbance estimation module inside the flux linkage observer, the disturbance of flux linkage is estimated and the amplitude of flux linkage observation is compensated, thereby enhancing the parameter robustness and anti-disturbance capability of the flux linkage observer.

[0066] Please see Figure 1 , Figure 1 This is a flowchart illustrating a sensorless motor control method provided in an embodiment of this application.

[0067] Here, the control method should be implemented through a magnetic flux observer, which can be installed on devices that require magnetic field observation and motor control, such as industrial robots, rail transit traction drives, CNC machine tool drives, industrial frequency converters, 3D printers, textile sewing machines, oil pump drives, water pump drives, fan drives, industrial power tools, air conditioners, washing machines, refrigerators, drones, balance scooters, treadmills, cooling fans, air purifiers, vacuum cleaners, floor scrubbers, and sweeping robots.

[0068] Here, the flux linkage observer in this scheme includes a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module. The flux linkage observer can be an active flux linkage observer or other types of flux linkage observers, which are not limited here.

[0069] The conventional formula for defining the flux linkage amplitude is:

[0070] ψ a =(L d -L q )i d +ψ r (1)

[0071] In formula (1), L d and L q Let ψ be the direct-axis inductance and quadrature-axis inductance of the motor. r It is the flux linkage amplitude of the permanent magnet, i d For direct-axis current, ψ a This is the flux linkage amplitude. Based on this flux linkage amplitude ψ... a The definition ensures compatibility with many types of AC synchronous motors, such as when motor L... d equal to L q And ψ r When the value is not 0, this motor is a surface-mounted permanent magnet synchronous motor; L d Less than Lq and ψ r The value is not 0, indicating that this motor is a built-in permanent magnet synchronous motor; L d Greater than L q And ψ r If the value is not 0, this motor is a permanent magnet assisted synchronous reluctance motor; L d Greater than L q And ψ r If the value is 0, this motor is a synchronous reluctance motor.

[0072] like Figure 1 As shown in the embodiments of this application, the control method includes:

[0073] S101, The flux linkage estimation module performs compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment.

[0074] Here, when the first output current, the first output voltage, and the estimated historical disturbance values ​​are located in a stationary coordinate system, the determined observed amplitude of the first flux linkage is also located in a stationary coordinate system. Furthermore, the first output current, the first output voltage, the estimated historical disturbance values, and the observed amplitude of the first flux linkage can also be located in other coordinate systems, which are not limited here.

[0075] The stationary coordinate system is also an αβ coordinate system, and the first flux linkage observation amplitude includes the flux linkage observation components on the α and β axes. The first output voltage is the stator voltage, and the first output voltage includes the stator voltage components on the α and β axes. The first output current is the stator current, and the first output current includes the stator current components on the α and β axes.

[0076] The "previous time" refers to the moment when the electrical angle of the rotor in the target motor was last determined. When the current time is the moment when the electrical angle of the rotor is first determined, the estimated value of the historical disturbance in the stationary coordinate system determined in the previous time is a preset value. For example, the estimated value of the historical disturbance in the stationary coordinate system determined in the previous time can be set to 0.

[0077] The flux linkage estimation module outputs the flux linkage observation amplitude after perturbation compensation.

[0078] In one embodiment provided in this application, the first output current and the first output voltage of the target motor are determined through the following steps:

[0079] S201. Obtain all phase voltages and all phase currents output by the target motor at the current moment.

[0080] S202. Perform coordinate system transformation on all phase voltages and all phase currents output by the target motor to determine the first output current and the first output voltage of the target motor at the current moment, and input the first output current and the first output voltage to the flux linkage estimation module.

[0081] For step S201, assuming the target motor is a three-phase motor, obtain all phase voltages and all phase currents output by the target motor at the current moment, and obtain the three-phase voltages and three-phase currents in the abc coordinate system (three-phase stationary natural coordinate system).

[0082] Regarding step S202, when the phase current and phase voltage are current and voltage in the abc coordinate system, when performing coordinate system transformation on all phase voltages and all phase currents output by the target motor, the specific process can be as follows: perform coordinate system transformation on all phase voltages and all phase currents output by the target motor according to the Clark transformation formula.

[0083] In another embodiment provided in this application, step S101, which involves the flux linkage estimation module performing compensation processing based on the first output current and first output voltage of the target motor at the current moment, and the estimated historical disturbance value determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment, includes:

[0084] S1011. Substitute the first output current and the first output voltage into the initial flux linkage equation preset in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment.

[0085] S1012. The initial magnetic flux observation amplitude is compensated using the historical disturbance estimate to determine the first magnetic flux observation amplitude.

[0086] S1012. The initial flux linkage observation amplitude is added to the historical disturbance estimate, and the sum is determined as the first flux linkage observation amplitude.

[0087] The initial flux linkage observation amplitude mentioned in step S1011 can be the initial flux linkage observation amplitude in a stationary coordinate system. The initial flux linkage observation amplitude includes the components of the initial flux linkage observation amplitude on the α-axis and the components on the β-axis. The initial flux linkage equation is an equation determined by back-derived from the voltage model.

[0088] Here, the initial flux linkage equation is:

[0089] ψ α =∫(u α -Ri α )dt-L q i α (2)

[0090] ψ β =∫(u β -Ri β )dt-L q i β (3)

[0091] The process for determining the initial magnetic flux linkage equation is as follows:

[0092] The motor voltage equation in the stationary coordinate system (αβ coordinate system) is:

[0093]

[0094]

[0095] In equations (4) and (5), R and Lq are the stator resistance and quadrature-axis inductance of the target motor, respectively, u α and u β These are the components of the first output voltage (stator voltage) on the α-axis and the β-axis, respectively. α and i β These are the components of the first output current (stator current) on the α-axis and the β-axis, respectively, ψ α and ψ β These represent the components of the flux linkage amplitude along the α-axis and the β-axis, respectively. Equations (4) and (5) can also be used as voltage models to observe the flux linkage ψ. α and ψ β Therefore, the initial flux linkage equations shown in equations (2) and (3) can be obtained by solving equations (4) and (5).

[0096] The historical disturbance estimate mentioned in step S1012 includes the components of the historical disturbance estimate on the α-axis and the components on the β-axis.

[0097] The initial flux linkage observation amplitude is compensated using the historical disturbance estimate to determine the first flux linkage observation amplitude. Specifically, the initial flux linkage observation amplitude can be added to the historical disturbance estimate to determine the first flux linkage observation amplitude.

[0098] The step of adding the initial flux linkage observation amplitude to the historical disturbance estimate includes: adding the components of the initial flux linkage observation amplitude and the historical disturbance estimate on the α-axis, and adding the components of the initial flux linkage observation amplitude and the historical disturbance estimate on the β-axis.

[0099] Thus, according to equations (2) and (3) and step S1012, the mathematical model of the flux linkage estimation module is:

[0100] ψ αe =∫(u α -Ri α )dt-L q i α +d α (6)

[0101] ψ βe =∫(u β -Ri β )dt-L q i β +d β (7)

[0102] In equations (6) and (7), ψ αe and ψ βe These represent the components of the observed flux linkage amplitude along the α-axis and the β-axis, respectively. α and d β These represent the components of the disturbance estimate on the α-axis and the β-axis, respectively.

[0103] When determining equations (6) and (7) based on equations (2) and (3), the following construction process is performed. d is defined as the flux disturbance caused by factors such as parameter variation, integral drift, high-frequency noise, measurement error, and voltage error. α and d β These represent the components of the disturbance estimate on the α-axis and the β-axis, respectively. d and d p These represent the components of the disturbance estimate on the d-axis (direct axis) and the p-axis (cross axis), respectively. Therefore, the flux linkage observation amplitude equation is defined as:

[0104] ψαe =ψ α +d α (13)

[0105] ψ βe =ψ β +d β (14)

[0106] Thus, by substituting equations (2) and (3) into equations (8) and (9) respectively, the mathematical model of the flux linkage estimation module can be determined, as shown in equations (6) and (7).

[0107] The disturbance estimate is the flux linkage disturbance caused by factors such as parameter variations, integral drift, high-frequency noise, measurement errors, and voltage errors. This scheme defines the flux linkage disturbance as the difference between the observed and actual flux linkage values.

[0108] The flux linkage estimation module can be constructed based on equations (6) and (7). Please refer to [link to relevant documentation]. Figure 2 , Figure 2 The schematic diagram of the flux linkage estimation module provided in this application is as follows: Figure 2 As shown, the symbol 1 / s represents integration.

[0109] In another embodiment provided in this application, after determining the estimated value of the first flux disturbance at the current moment, the control method further includes: the disturbance estimation module feeding back the estimated value of the first flux disturbance to the flux estimation module so that the flux estimation module can update the estimated value of the historical disturbance.

[0110] S102. The disturbance estimation module determines the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment.

[0111] In this step, the disturbance estimation module determines the estimated value of the first flux disturbance at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and the historical position electrical angle of the rotor in the target motor determined at the previous moment. Also, the disturbance estimation module determines the cross-axis flux amplitude based on the first flux observed amplitude and the historical position electrical angle of the rotor in the target motor determined at the previous moment.

[0112] Specifically, if the given flux linkage amplitude is located in a synchronous rotating coordinate system, and the estimated value of the first flux linkage disturbance is located in a stationary coordinate system, and the determined cross-axis flux linkage amplitude is located in a synchronous rotating coordinate system, coordinate transformation is required. The historical position electrical angle is a necessary parameter for coordinate transformation.

[0113] The synchronous rotating coordinate system is also a dq coordinate system; for an example, please refer to [link to example]. Figure 3 , Figure 3 This is a schematic diagram of a stationary coordinate system and a synchronously rotating coordinate system. (See diagram below.) Figure 3 As shown, the αβ coordinate system is a stationary coordinate system, the dq coordinate system is a synchronously rotating coordinate system, and θ r The electrical angle represents the position of the rotor in the motor.

[0114] Based on the electrical angle of the rotor position in the motor and formula (1), the flux linkage equation can be obtained as follows:

[0115] ψ α =ψ a cos(θ r (10)

[0116] ψ β =ψ a sin(θ r (11)

[0117] Thus, θ is defined re To estimate the electrical angle of the rotor position in the motor, the Park transform formula is used to calculate the flux linkage components ψ on the d-axis and q-axis. d and ψ q As shown in equations (12) and (13):

[0118] ψ d =ψ α cos(θ re )+ψ β sin(θ re (12)

[0119] ψ q =ψ α (-sin(θ re ))+ψ β cos(θ re (13)

[0120] In equations (12) and (13), ψ d and ψ q Let the direct-axis flux linkage and the quadrature-axis flux linkage be respectively. Substituting equations (10) and (11) into equations (12) and (13) yields:

[0121] ψ d =ψ a cos(θ r cos(θ) re )+ψ a sin(θ r sin(θ) re (14)

[0122] ψ q =ψ a cos(θ r (-sin(θ)) re ))+ψ a sin(θ r cos(θ) re (15)

[0123] Simplifying equation (15) using the product-to-sum formula yields:

[0124] ψ q =ψ a *sin(θ r -θ re (16)

[0125] From equation (16), it can be seen that when the actual rotor's position electrical angle θ r With respect to the estimated rotor position electrical angle θ re When the difference approaches zero, the quadrature-axis flux linkage also approaches zero, and as can be seen from equation (14), the value of the direct-axis flux linkage at this time approaches the flux linkage amplitude. Therefore, the direct-axis flux linkage contains the flux linkage amplitude information, while the quadrature-axis flux linkage contains the error information of the rotor's position electrical angle.

[0126] Thus, according to equations (14) to (16), when the actual rotor position electrical angle is different from the estimated rotor position electrical angle θ re When the difference approaches zero, the direct-axis flux linkage and the quadrature-axis flux linkage approach their respective flux linkage amplitudes and zero. Therefore, the given flux linkage amplitude ψ in the synchronously rotating coordinate system can be calculated according to equations (17) and (18). qref and ψ dref .

[0127] ψ qref =0 (17)

[0128]

[0129] In equations (17) and (18), ψ dref and Ψ qref These are the components of the magnetic flux given its magnitude on the d-axis and q-axis, respectively.

[0130] In one embodiment provided in this application, step S102, in which the disturbance estimation module determines the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired given flux amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment, includes:

[0131] S1021. Based on the historical position electrical angle, perform coordinate system transformation on the first magnetic flux observation amplitude to determine the second magnetic flux observation amplitude at the current moment; wherein, the second magnetic flux observation amplitude includes the cross-axis magnetic flux amplitude.

[0132] S1022. Determine the flux error amplitude at the current moment based on the difference between the observed flux amplitude and the given flux amplitude.

[0133] S1023. Input the flux linkage error amplitude into the proportional-integral estimation formula preset in the disturbance estimation module to determine the estimated value of the second flux linkage disturbance at the current moment; wherein, the proportional-integral estimation formula is a formula that characterizes the mapping relationship between error and disturbance after introducing proportional gain and integral gain.

[0134] S1024. Based on the historical position electrical angle, perform coordinate system transformation on the estimated value of the second magnetic flux disturbance to determine the estimated value of the first magnetic flux disturbance.

[0135] For steps S1021 to S1024, the execution entity is the disturbance estimation module.

[0136] Specifically, the coordinate system transformation processing of the first magnetic flux observation amplitude based on the historical position electrical angle described in step S1021 can be performed by inputting the first magnetic flux observation amplitude and the historical position electrical angle into the Park transformation formula preset in the disturbance estimation module to determine the second magnetic flux observation amplitude in the synchronous rotating coordinate system at the current moment.

[0137] Regarding step S1022, determining the flux linkage error amplitude at the current moment based on the difference between the observed flux linkage amplitude and the given flux linkage amplitude specifically involves:

[0138] e d =ψ dref -ψ d (19)

[0139] e q =ψ qref -ψ q (20)

[0140] The proportional-integral estimation formula described in step S1023 can specifically take the following form:

[0141] d d =k p e d +k i ∫e d dt (21)

[0142] dq =k p e q +k i ∫e q dt (22)

[0143] Where, d d and d q These are the components of the flux linkage disturbance d along the d-axis and q-axis, respectively, and k p and k i These are the proportional gain and integral gain, respectively. Since both the feedback and the given quantity of the disturbance estimation module are DC quantities, the input error of the disturbance estimation module is also a DC quantity, and its proportional gain and integral gain can be adjusted according to the system bandwidth.

[0144] Therefore, a disturbance estimation module can be constructed based on equations (17) to (22). Please refer to [link / reference]. Figure 4 , Figure 4 The schematic diagram of the disturbance estimation module provided in this application is as follows: Figure 4 As shown, the PI symbol represents the calculation process using the proportional-integral estimation formula, the αβ / dq symbol represents the Park transform formula, and the dq / αβ symbol represents the inverse Park transform formula.

[0145] Thus, by Figure 3 and Figure 4 It can be seen that the components of the flux disturbance estimate d determined by equations (21) and (22) on the d-axis and q-axis can be obtained by using the Park inverse transform formula. d and d p Converted to components of flux linkage disturbance d along the α and β axes α and d β Then, the components ψ of the flux linkage amplitude on the α and β axes after perturbation compensation are observed using the flux linkage observation equations shown in equations (6) and (7). αe and ψ βe This enhances the parameter robustness and disturbance rejection capability of the magnetic flux observer.

[0146] In one embodiment provided in this application, after determining the estimated value of the first flux linkage disturbance at the current moment, the control method further includes: the disturbance estimation module feeding back the estimated value of the first flux linkage disturbance to the flux linkage estimation module, so that the flux linkage estimation module can update the estimated value of the historical disturbance.

[0147] S103. The rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the cross-axis flux linkage amplitude and through phase-locked loop processing.

[0148] In this step, the target position electrical angle is used to output a control signal to control the target motor.

[0149] In one embodiment provided in this application, step S103, in which the rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the cross-axis flux linkage amplitude and through phase-locked loop processing, includes:

[0150] S1031. The proportional-integral unit in the rotor angle estimation module determines the current angular velocity of the rotor in the target motor based on the amplitude of the cross-axis flux linkage.

[0151] S1032. The integration unit in the rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the electrical angular velocity.

[0152] For step S1031, a proportional-integral calculation formula is set in the proportional-integral unit.

[0153] For an example, please refer to Figure 5 , Figure 5 This is a schematic diagram of the rotor angle estimation module provided in this application, as shown below. Figure 5 As shown, ω re Let be the electric angular velocity of the rotor in the target motor.

[0154] In another embodiment provided in this application, after determining the target position electrical angle of the rotor in the target motor at the current moment, the control method further includes: the rotor angle estimation module feeding back the target position electrical angle to the disturbance estimation module so that the disturbance estimation module can update the historical position electrical angle.

[0155] Thus, based on the descriptions of steps S101 to S103 above, the data processing principle in the magnetic flux observer is as follows: Figure 6 As shown, Figure 6 The internal schematic diagram of the magnetic flux observer provided in this application is as follows: Figure 6 As shown, the flux linkage observer itself estimates the flux linkage disturbance and compensates for the flux linkage observation value, thereby eliminating the influence of factors such as parameter variation, integral drift, high-frequency noise, and measurement error on the flux linkage observation value, thus enhancing the parameter robustness and disturbance rejection capability of the flux linkage observer. This scheme does not require the design of additional filters and is independent of the voltage / current model of the flux linkage, and is applicable to AC motor drive systems such as permanent magnet synchronous motors, permanent magnet assisted synchronous reluctance motors, and synchronous reluctance motors.

[0156] For an example, please refer to Figure 7 Taking a sensorless magnetic field orientation vector control system as an example, Figure 7 This is a block diagram of a sensorless motor field orientation vector control system, such as... Figure 7As shown, the flux linkage observer provides the control system with estimated values ​​of the motor rotor position electrical angle and the motor rotor electrical angular velocity. Furthermore, the flux linkage observer proposed in this invention can also be applied to other sensorless motor control systems such as direct torque control.

[0157] Thus, this application constructs a disturbance estimation module within the flux linkage observer. The observer itself estimates the flux linkage disturbance and compensates for the flux linkage observation values, thereby eliminating the influence of factors such as parameter variations, integral drift, high-frequency noise, and measurement errors on the flux linkage observation values. This enhances the parameter robustness and disturbance resistance of the flux linkage observer, ultimately improving the accuracy of the rotor position electrical angle determination results in the motor.

[0158] Please see Figure 8 , Figure 8 This is a schematic diagram of a sensorless motor control system provided in an embodiment of this application. Figure 8 As shown, the control system 800 includes a flux linkage observer 810, which includes a flux linkage estimation module 811, a disturbance estimation module 812, and a rotor angle estimation module 813.

[0159] The flux linkage estimation module 811 is used to perform compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment.

[0160] The disturbance estimation module 812 is used to determine the estimated value of the first flux disturbance and the cross-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment.

[0161] The rotor angle estimation module 813 is used to determine the target position electrical angle of the rotor in the target motor at the current moment based on the amplitude of the cross-axis flux linkage and through phase-locked loop processing; the target position electrical angle is used to output a control signal to control the target motor.

[0162] Optionally, the control system 800 further includes a determining module 820, the determining module 820 being used for:

[0163] Obtain all phase voltages and all phase currents output by the target motor at the current moment;

[0164] The target motor outputs all phase voltages and all phase currents by performing coordinate system transformation to determine the first output current and the first output voltage of the target motor at the current moment, and then inputs the first output current and the first output voltage to the flux linkage estimation module.

[0165] Optionally, when the flux linkage estimation module 811 performs compensation processing based on the first output current and first output voltage of the target motor at the current moment, and the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment, the flux linkage estimation module 811 is used to:

[0166] Substitute the first output current and the first output voltage into the initial flux linkage equation preset in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment.

[0167] The initial flux linkage observation amplitude is compensated using the historical disturbance estimate to determine the first flux linkage observation amplitude.

[0168] Optionally, when the disturbance estimation module 812 is used to determine the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired flux given amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment, the disturbance estimation module 812 is used to:

[0169] Based on the historical position electrical angle, the first magnetic flux observation amplitude is transformed using coordinate system transformation to determine the second magnetic flux observation amplitude at the current moment; wherein, the second magnetic flux observation amplitude includes the cross-axis magnetic flux amplitude;

[0170] The flux linkage error amplitude at the current moment is determined based on the difference between the observed amplitude of the second flux linkage and the given amplitude of the flux linkage.

[0171] The flux linkage error amplitude is input into the proportional-integral estimation formula pre-set in the disturbance estimation module to determine the estimated value of the second flux linkage disturbance at the current moment; wherein, the proportional-integral estimation formula is a formula that characterizes the mapping relationship between error and disturbance after introducing proportional gain and integral gain;

[0172] Based on the historical position electrical angle, the estimated value of the second magnetic flux disturbance is transformed using coordinate system transformation to determine the estimated value of the first magnetic flux disturbance.

[0173] Optionally, when the rotor angle estimation module 813 is used to determine the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude and after phase-locked loop processing, the rotor angle estimation module 813 is used to:

[0174] The proportional-integral unit in the rotor angle estimation module determines the current electric angular velocity of the rotor in the target motor based on the cross-axis flux linkage amplitude.

[0175] The integral unit in the rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the electrical angular velocity.

[0176] Optionally, the disturbance estimation module 812 is further configured to:

[0177] The first flux linkage disturbance estimate is fed back to the flux linkage estimation module 811 so that the flux linkage estimation module 811 can update the historical disturbance estimate.

[0178] Optionally, the rotor angle estimation module 813 is further used for:

[0179] The target position electrical angle is fed back to the disturbance estimation module 812 so that the disturbance estimation module 812 can update the historical position electrical angle.

[0180] Please see Figure 9 , Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 9 As shown, the electronic device 900 includes a processor 910, a memory 920, and a bus 930.

[0181] The memory 920 stores machine-readable instructions executable by the processor 910. When the electronic device 900 is running, the processor 910 and the memory 920 communicate via the bus 930. When the machine-readable instructions are executed by the processor 910, they can perform the operations described above. Figure 1 Figure 2 , Figures 4 to 7 The steps in the method embodiment shown are specifically implemented in the method embodiment and will not be repeated here.

[0182] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can perform the above-described actions. Figure 1 Figure 2 , Figures 4 to 7 The steps in the method embodiment shown are specifically implemented in the method embodiment and will not be repeated here.

[0183] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0184] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0185] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0186] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0187] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0188] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for a sensorless motor, characterized in that, This is achieved through a flux linkage observer, which includes a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module. The control method includes: The flux linkage estimation module performs compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated historical disturbance value determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment. Specifically, this includes: substituting the first output current and the first output voltage into the initial flux linkage equation pre-set in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment; and using the estimated historical disturbance value to compensate for the initial flux linkage observation amplitude to determine the first flux linkage observation amplitude. The disturbance estimation module determines the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired given flux amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment. After determining the estimated value of the first flux disturbance at the current moment, the control method further includes: the disturbance estimation module feeding back the estimated value of the first flux disturbance to the flux estimation module so that the flux estimation module can update the historical disturbance estimation value. The rotor angle estimation module determines the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude through a phase-locked loop. Specifically, this includes: the proportional-integral unit in the rotor angle estimation module determining the electrical angular velocity of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude; and the integral unit in the rotor angle estimation module determining the target position electrical angle of the rotor in the target motor at the current moment based on the electrical angular velocity. The target position electrical angle is used to output a control signal for controlling the target motor. After determining the target position electrical angle of the rotor in the target motor at the current moment, the control method further includes: the rotor angle estimation module feeding back the target position electrical angle to the disturbance estimation module so that the disturbance estimation module can update the historical position electrical angle.

2. The control method according to claim 1, characterized in that, The first output current and the first output voltage of the target motor are determined by the following steps: Obtain all phase voltages and all phase currents output by the target motor at the current moment; The target motor outputs all phase voltages and all phase currents by performing coordinate system transformation to determine the first output current and the first output voltage of the target motor at the current moment, and then inputs the first output current and the first output voltage to the flux linkage estimation module.

3. The control method according to claim 1, characterized in that, The step of the disturbance estimation module determining the estimated value of the first flux disturbance and the quadrature-axis flux amplitude at the current moment based on the first flux observed amplitude, the pre-acquired given flux amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment includes: Based on the historical position electrical angle, the first magnetic flux observation amplitude is transformed using coordinate system transformation to determine the second magnetic flux observation amplitude at the current moment; wherein, the second magnetic flux observation amplitude includes the cross-axis magnetic flux amplitude; The flux linkage error amplitude at the current moment is determined based on the difference between the observed amplitude of the second flux linkage and the given amplitude of the flux linkage. The flux linkage error amplitude is input into the proportional-integral estimation formula pre-set in the disturbance estimation module to determine the estimated value of the second flux linkage disturbance at the current moment; wherein, the proportional-integral estimation formula is a formula that characterizes the mapping relationship between error and disturbance after introducing proportional gain and integral gain; Based on the historical position electrical angle, the estimated value of the second magnetic flux disturbance is transformed using coordinate system transformation to determine the estimated value of the first magnetic flux disturbance.

4. A control system for a sensorless motor, characterized in that, To implement the control method according to any one of claims 1-3, the control system includes a flux linkage observer, which includes a flux linkage estimation module, a disturbance estimation module, and a rotor angle estimation module. The flux linkage estimation module is used to perform compensation processing based on the first output current and first output voltage of the target motor at the current moment, as well as the estimated value of the historical disturbance determined at the previous moment, to determine the first flux linkage observation amplitude at the current moment. The flux linkage estimation module is specifically used to: substitute the first output current and the first output voltage into the initial flux linkage equation preset in the flux linkage estimation module to determine the initial flux linkage observation amplitude at the current moment; The initial flux linkage observation amplitude is compensated using the historical disturbance estimate to determine the first flux linkage observation amplitude; The disturbance estimation module is used to determine the estimated value of the first magnetic flux disturbance and the quadrature-axis magnetic flux amplitude at the current moment based on the first magnetic flux observed amplitude, the pre-acquired given magnetic flux amplitude, and all or part of the parameters in the historical position electrical angle of the rotor in the target motor determined at the previous moment; the disturbance estimation module is also used to: feed back the estimated value of the first magnetic flux disturbance to the magnetic flux estimation module so that the magnetic flux estimation module can update the historical disturbance estimation value; The rotor angle estimation module is used to determine the target position electrical angle of the rotor in the target motor at the current moment based on the quadrature-axis flux linkage amplitude and through phase-locked loop processing. Specifically, the rotor angle estimation module is used to: determine the electrical angular velocity of the rotor in the target motor at the current moment using the proportional-integral unit based on the quadrature-axis flux linkage amplitude; and determine the target position electrical angle of the rotor in the target motor at the current moment using the integral unit based on the electrical angular velocity. The target position electrical angle is used to output a control signal for controlling the target motor. The rotor angle estimation module is also used to: feed back the target position electrical angle to the disturbance estimation module so that the disturbance estimation module can update the historical position electrical angle.

5. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus, and the machine-readable instructions are executed by the processor to perform the steps of the control method as described in any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the control method as described in any one of claims 1 to 3.

Images