Method and system for controlling brushless motor without position sensor based on state observer

Abstract

The invention relates to the technical field of brushless motor control, in particular to a position-sensorless brushless motor control method and system based on a state observer, and the method comprises the steps: carrying out the current detection of a brushless motor to be detected, obtaining an original operation current set, constructing an original observation model of the state observer, obtaining an observation operation current set through the original observation model, and obtaining a position-sensorless brushless motor. Calculating an observation error value of the observation operation current set and the original operation current set, judging whether the observation error value is greater than a minimum error value, if so, adjusting the original observation model to obtain an adjusted observation model, and calculating the observation error value again until the observation error value is not less than the minimum error value to obtain a target observation model; and calculating an observation rotor position angle and an observation rotor rotating speed according to the target observation model. According to the invention, the accuracy of rotor parameter detection and the stability of motor control during brushless motor control can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of brushless motor control, and in particular to a position sensorless brushless motor control method and system based on a state observer. Background Art

[0002] As a high-performance motor system, brushless motors are widely used in aerospace, electric vehicles, industrial automation, home appliances and other fields due to their advantages such as high efficiency, high power density, low noise and long life. However, the control of brushless motors usually relies on position sensors such as Hall sensors to obtain rotor position information to achieve precise commutation control. This sensor-dependent approach has some limitations, such as increased sensor installation costs, reduced reliability, increased size and limited applicability in harsh environments. Therefore, in some usage environments, a brushless motor control method without a position sensor is needed to replace the brushless motor control method with a position sensor.

[0003] The current position sensorless brushless motor control method is mainly implemented through the back-EMF detection method. However, this method has low detection accuracy of the rotor position and speed when the motor is in a low-speed state and the startup phase due to the weak back-EMF signal. In addition, when the motor parameters change or the load changes suddenly, the stability of the control system will decrease. Summary of the invention

[0004] The present invention provides a position sensorless brushless motor control method and system based on a state observer, the main purpose of which is to improve the accuracy of rotor parameter detection during brushless motor control and the stability of motor control.

[0005] To achieve the above object, the present invention provides a position sensorless brushless motor control method based on a state observer, comprising: receiving a motor control instruction, and starting the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer; Performing current detection on the brushless motor to be tested based on a current detector to obtain an original operating current set, wherein the original operating current set includes a plurality of original operating currents, and each original operating current includes an original vertical current and an original parallel current; Constructing an original observation model of the state observer; Using the original observation model, the state parameters of the brushless motor to be measured are calculated to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; Performing observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value, and determining whether the observation error value is greater than a preset minimum error value; If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The adjustment observation model is used as the original observation model, and the step of calculating the state parameters of the brushless motor to be tested by using the original observation model is returned until the observation error value is not greater than the minimum error value, and the original observation model at this time is recorded as the target observation model; According to the target observation model, the observed rotor position angle and the observed rotor speed are calculated, and based on the observed rotor position angle and the observed rotor speed, the position sensorless brushless motor control based on the state observer is completed.

[0006] Optionally, the current detection of the brushless motor to be tested is performed based on a current detector to obtain an original operating current set, including: Under a preset current detection cycle, the current detector is used to monitor the current signal to obtain a continuous operating current, wherein the continuous operating current is a current signal that changes continuously under the current detection cycle; A sampling period of the state observer is obtained, and based on the sampling period, discrete current sampling is performed in the continuous operating current to obtain an original operating current set.

[0007] Optionally, constructing the original observation model of the state observer includes: Setting a current current variable and a historical current variable, wherein the current current variable includes: a current vertical current variable and a current parallel current variable, and the historical current variable includes: a historical vertical current variable and a historical parallel current variable; Based on the sampling period, the current current variable and the historical current variable, an original observation model is constructed, wherein the original observation model is expressed as: in, represents the original observation model, Represents the current vertical current variable, represents the historical vertical current variable, represents the sampling period, represents the preset inductance variable, Represents the preset vertical voltage variable, Represents the preset resistance variable, Represents the preset original vertical control factor, represents the current parallel current variable, represents the historical parallel current variable, Table preset parallel voltage variables, Represents the preset original parallel control factor.

[0008] Optionally, the use of the original observation model to calculate the state parameters of the brushless motor to be measured to obtain an observed operating current set includes: In the step of performing current detection on the brushless motor to be tested based on the current detector, a voltage detector, a resistance detector and an inductance detector are used to perform synchronous parameter detection on the brushless motor to be tested, so as to obtain a synchronous motor parameter set, wherein the synchronous motor parameter set includes a plurality of synchronous motor parameters, and the synchronous motor parameters include: synchronous motor resistance, synchronous motor inductance, synchronous vertical voltage and synchronous parallel voltage; If the step of performing synchronous parameter detection on the brushless motor to be tested is the first time to perform synchronous parameter detection, the preset zero values ​​are recorded as the historical vertical current and the historical parallel current respectively; If the step of performing synchronous parameter detection on the brushless motor to be tested is not the first time to perform synchronous parameter detection, querying the historical vertical current and the historical parallel current; Extracting synchronous motor parameters in the synchronous motor parameter set in sequence, substituting the synchronous motor parameters, historical vertical current and historical parallel current into the original observation model to obtain an observed operating current, wherein the observed operating current includes an observed vertical current and an observed parallel current; The observed operating currents are summarized to obtain an observed operating current set.

[0009] Optionally, performing observation error analysis according to the observed operating current set and the original operating current set to obtain an observation error value includes: According to the observed operating current set and the original operating current set, effective current data analysis is performed to obtain an effective current error factor set and an effective fluctuation weight set; Based on the effective current error factor set and the effective fluctuation weight set, the observation error value is calculated using the following formula: in, represents the observation error value, represents the number of effective current error factors in the effective current error factor set or the number of effective fluctuation weights in the effective fluctuation weight set, represents the first The effective volatility weight, Indicates the effective current error factor concentration An effective current error factor.

[0010] Optionally, performing effective current data analysis according to the observed operating current set and the original operating current set to obtain an effective current error factor set and an effective fluctuation weight set includes: Recording the time when the step of performing current detection on the brushless motor to be tested based on the current detector is completed; Extracting the observed operating current and the original operating current corresponding to the extracted observed operating current from the observed operating current set and the original operating current set respectively, obtaining the current collection moments of the observed operating current and the original operating current, and calculating the time length fluctuation weight between the detection completion moment and the current collection moment; Calculate the unit current error factor; If it is confirmed that the unit current error factor is not greater than the preset controllable error factor, the unit current error factor and the time fluctuation weight are recorded as the effective current error factor and the effective fluctuation weight respectively; The effective current error factors and effective fluctuation weights are respectively summarized to obtain an effective current error factor set and an effective fluctuation weight set.

[0011] Optionally, the calculating the unit current error factor includes: Based on the observed operating current and the original operating current, a unit current error factor is calculated, wherein the unit current error factor is expressed as: in, represents the unit current error factor, Represents the original vertical current in the original operating current, Represents the observed vertical current in the observed operating current, Represents the original parallel current in the original operating current, Represents the observed parallel current in the observed operating current.

[0012] Optionally, adjusting the original observation model to obtain an adjusted observation model includes: The adjustment amplitude factor is set based on the sampling period, wherein the adjustment amplitude factor is expressed as: Among them, the represents the adjustment amplitude factor, Indicates the preset selection constant; According to the adjustment amplitude factor, the adjustment vertical control factor and the adjustment parallel control factor are calculated using the following formula: in, represents the adjustment of the vertical control factor, represents the adjustment of parallel control factors; The adjusted vertical control factor and the adjusted parallel control factor are used to replace the original vertical control factor and the original parallel control factor in the original observation model respectively, so as to obtain the adjusted observation model.

[0013] Optionally, calculating the observed rotor position angle and the observed rotor speed according to the target observation model includes: Identifying a target vertical control factor and a target parallel control factor in the target observation model; Using a preset low-pass filter to extract the vertical back electromotive force in the target vertical control factor and the parallel back electromotive force in the target parallel control factor respectively; According to the vertical back electromotive force and the parallel back electromotive force, the observed rotor position angle and the observed rotor speed are calculated, wherein the observed rotor position angle and the observed rotor speed are respectively expressed as: in, represents the observed rotor position angle, represents the four-quadrant inverse tangent function, represents the vertical back EMF, represents the parallel back EMF, represents the observed rotor speed, Indicates the preset back-EMF constant.

[0014] To achieve the above object, the present invention also provides a position sensorless brushless motor control system based on a state observer, comprising: An original current acquisition module is used to receive a motor control instruction, and start the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer, and performs current detection on the brushless motor to be tested based on the current detector to obtain an original operating current set, wherein the original operating current set includes multiple original operating currents, and each original operating current includes an original vertical current and an original parallel current; A motor current observation module is used to construct an original observation model of the state observer, and to calculate the state parameters of the brushless motor to be measured by using the original observation model to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; an observation model adjustment module, configured to perform observation error analysis according to the observed operating current set and the original operating current set to obtain an observation error value, and determine whether the observation error value is greater than a preset minimum error value; if the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The rotor parameter calculation module is used to use the adjusted observation model as the original observation model, return to the step of using the original observation model to calculate the state parameters of the brushless motor to be tested, until the observation error value is no greater than the minimum error value, and record the original observation model at this time as the target observation model, and calculate the observed rotor position angle and the observed rotor speed according to the target observation model.

[0015] In order to solve the above problem, the present invention further provides an electronic device, the electronic device comprising: A memory storing at least one instruction; The processor executes the instructions stored in the memory to implement the above-mentioned position sensorless brushless motor control method based on the state observer.

[0016] In order to solve the above problems, the present invention also provides a computer-readable storage medium, in which at least one instruction is stored. The at least one instruction is executed by a processor in an electronic device to implement the above-mentioned state observer-based position sensorless brushless motor control method.

[0017] In order to solve the problem described in the background technology, the present invention first starts a brushless motor to be tested, which does not include a position sensor and a speed sensor, thereby reducing the cost, complexity and failure risk of controlling the brushless motor to be tested. Then, the current detection is performed on the brushless motor to be tested based on a current detector to obtain an original operating current set. This step can obtain the current information of the motor in real time, including vertical current and parallel current, and provide basic data for subsequent state estimation. Then, the resistance, inductance and other parameters in the brushless motor to be tested are detected, and an original observation model of the state observer is constructed based on these parameters. The model can describe the dynamic characteristics of the motor when it is running, and provides a specific calculation method for the subsequent estimation of the rotor position and the rotor speed. Furthermore, the original observation model is used to calculate the state parameters of the brushless motor to be tested, and the state parameters are obtained. The observed operating current set is obtained, and the observed error value between the original operating current set and the observed operating current set is calculated, and the dynamic adjustment of the original observation model is completed based on the observed error value. This adjustment method can gradually adjust the original observation model of the state observer so that the observation model always maintains the optimal state, thereby achieving high-precision tracking of the motor operating state. This method not only improves the accuracy of rotor position and rotor speed detection, but also enhances the stability of motor control. Through the above-mentioned dynamic adjustment mechanism, the target observation model finally obtained can estimate the rotor position angle and speed with high accuracy, especially in the low-speed operation and startup stage. Traditional methods are often difficult to accurately obtain rotor position information. This method can effectively solve this problem by continuously adjusting the original observation model, thereby achieving stable control within the full speed range. Therefore, the present invention can improve the accuracy of rotor parameter detection and the stability of motor control during brushless motor control. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic flow chart of a method for controlling a brushless motor without a position sensor based on a state observer provided by an embodiment of the present invention; Figure 2 A functional module diagram of a position sensorless brushless motor control system based on a state observer provided by an embodiment of the present invention; Figure 3 A schematic diagram of the structure of an electronic device for implementing the position sensorless brushless motor control method based on a state observer provided in an embodiment of the present invention.

[0019] Description of reference numerals: 1. Electronic device; 10. Processor; 11. Memory; 12. Bus.

[0020] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0022] The embodiment of the present application provides a method for controlling a brushless motor without a position sensor based on a state observer. The execution subject of the method for controlling a brushless motor without a position sensor based on a state observer includes but is not limited to at least one of the electronic devices such as a server and a terminal that can be configured to execute the method provided by the embodiment of the present application. In other words, the method for controlling a brushless motor without a position sensor based on a state observer can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes but is not limited to: a single server, a server cluster, a cloud server or a cloud server cluster, etc.

[0023] Reference Figure 1 FIG. 1 is a flow chart of a method for controlling a brushless motor without a position sensor based on a state observer according to an embodiment of the present invention. In this embodiment, the method for controlling a brushless motor without a position sensor based on a state observer includes: S1. Receive a motor control instruction, and start a brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer.

[0024] It can be understood that the motor control instruction refers to an instruction initiated manually to control the brushless motor, and the motor control instruction includes the model of the brushless motor to be controlled, wherein the brushless motor refers to a motor without brushes and commutators. Compared with traditional motors, the motor can be driven by electronic commutation, and thus has the advantages of high efficiency, long life, low noise, etc. The brushless motor to be tested refers to the brushless motor to be controlled contained in the motor control instruction, the current detector refers to a device for measuring the running current in the brushless motor, the voltage detector refers to a device for measuring the running voltage in the brushless motor, the resistance detector refers to a device for measuring the resistance in the brushless motor, because the resistance in the brushless motor will change with the increase of the operating temperature, it is necessary to use a resistance detector to detect the resistance in the motor in real time, the inductance detector refers to a device for measuring the inductance in the brushless motor, and the state observer refers to a device for estimating the rotor position and rotor speed of the brushless motor based on a mathematical model algorithm and measurable parameters of the brushless motor, such as the current and voltage of the motor.

[0025] Furthermore, in traditional motor control systems, position sensors and speed sensors, such as Hall sensors and encoders, are usually required to detect the position and speed of the motor rotor. However, position sensors and speed sensors will increase the cost, complexity and failure risk of the system. Therefore, the rotor position and speed can be indirectly estimated through information such as the motor's current and voltage, thereby achieving control of the motor while reducing the control cost and failure risk of the motor.

[0026] S2. Perform current detection on the brushless motor to be tested based on a current detector to obtain an original operating current set, wherein the original operating current set includes multiple original operating currents, and each original operating current includes an original vertical current and an original parallel current.

[0027] It can be understood that the original operating current set refers to the set of original operating currents, the original operating current refers to the current value of the brushless motor when it is running, the original vertical current refers to the current whose direction is perpendicular to the direction of the rotor magnetic field, and the original parallel current refers to the current whose direction is parallel to the direction of the rotor magnetic field.

[0028] It should be explained that the signal obtained by using a current detector to detect the brushless motor to be tested is a continuously changing current signal, but in the actual brushless motor control system, it is impossible to directly process the continuous current signal, so it is necessary to discretize the continuous current signal to obtain the original operating current set, where discretization refers to extracting discrete current signals from the continuous current signal.

[0029] In detail, the current detection of the brushless motor to be tested is performed based on a current detector to obtain an original operating current set, including: Under a preset current detection cycle, the current detector is used to monitor the current signal to obtain a continuous operating current, wherein the continuous operating current is a current signal that changes continuously under the current detection cycle; A sampling period of the state observer is obtained, and based on the sampling period, discrete current sampling is performed in the continuous operating current to obtain an original operating current set.

[0030] It can be understood that the current detection period refers to the duration of current signal monitoring of the brushless motor, the continuous operating current refers to the continuously changing current signal, the sampling period refers to the time interval between collecting two original operating currents in the continuous operating current, and the specific value of the sampling period can be set manually, and the discrete current collection refers to determining an original operating current every current sampling interval in the continuous operating current.

[0031] S3. Constructing an original observation model of the state observer.

[0032] It can be understood that the original observation model refers to a data model used by the state observer to estimate the parameters of the brushless motor to be tested. The rotor position and rotor speed of the brushless motor to be tested can be estimated through the original observation model.

[0033] In detail, the construction of the original observation model of the state observer includes: Setting a current current variable and a historical current variable, wherein the current current variable includes: a current vertical current variable and a current parallel current variable, and the historical current variable includes: a historical vertical current variable and a historical parallel current variable; Based on the sampling period, the current current variable and the historical current variable, an original observation model is constructed, wherein the original observation model is expressed as: in, represents the original observation model, Represents the current vertical current variable, represents the historical vertical current variable, represents the sampling period, represents the preset inductance variable, Represents the preset vertical voltage variable, Represents the preset resistance variable, Represents the preset original vertical control factor, represents the current parallel current variable, represents the historical parallel current variable, Table preset parallel voltage variables, Represents the preset original parallel control factor.

[0034] It can be understood that the current vertical current variable refers to the dependent variable used to represent the current vertical current in the original observation model, the current parallel current variable refers to the dependent variable used to represent the current parallel current in the original observation model, the historical vertical current variable refers to the independent variable used to represent the historical vertical current in the original observation model, the historical parallel current variable refers to the independent variable used to represent the historical parallel current in the original observation model, the inductance variable refers to the independent variable used to represent the inductance in the original observation model, the resistance variable refers to the independent variable used to represent the resistance in the original observation model, the vertical voltage variable refers to the independent variable of the voltage in the vertical direction, the parallel voltage variable refers to the independent variable of the voltage in the parallel direction, the original vertical control factor refers to the parameter for error compensation of the observation parameters in the vertical direction, and the original parallel control factor refers to the parameter for error compensation of the observation parameters in the parallel direction.

[0035] Furthermore, since a state observer is used to estimate the state parameters of the brushless motor to be tested, there is a certain error between the observed values ​​and the actual parameters of the brushless motor to be tested. For example, there is a numerical error between the observed vertical current of the brushless motor to be tested estimated by the state observer and the actual original vertical current. In order to reduce this error, it is necessary to introduce a control factor, which includes a vertical control factor and a parallel control factor, to compensate for this error. When the original observation model at this time is constructed for the first time, the original vertical control factor and the original parallel control factor at this time can be set manually. When the original observation model at this time is not constructed for the first time, the original vertical control factor and the original parallel control factor at this time are the vertical control factor and the parallel control factor in the observation model obtained in the previous sampling period.

[0036] S4. Calculate the state parameters of the brushless motor to be measured by using the original observation model to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set.

[0037] It can be understood that the observed operating current set refers to a collection of observed operating currents, and the observed operating current refers to the operating current of the brushless motor to be tested obtained after calculation by the original observation model, and the observed operating current corresponds to the original operating current collected by the current detector.

[0038] In detail, the original observation model is used to calculate the state parameters of the brushless motor to be measured to obtain the observed operating current set, including: In the step of performing current detection on the brushless motor to be tested based on the current detector, a voltage detector, a resistance detector and an inductance detector are used to perform synchronous parameter detection on the brushless motor to be tested, so as to obtain a synchronous motor parameter set, wherein the synchronous motor parameter set includes a plurality of synchronous motor parameters, and the synchronous motor parameters include: synchronous motor resistance, synchronous motor inductance, synchronous vertical voltage and synchronous parallel voltage; If the step of performing synchronous parameter detection on the brushless motor to be tested is the first time to perform synchronous parameter detection, the preset zero values ​​are recorded as the historical vertical current and the historical parallel current respectively; If the step of performing synchronous parameter detection on the brushless motor to be tested is not the first time to perform synchronous parameter detection, querying the historical vertical current and the historical parallel current; Extracting synchronous motor parameters in the synchronous motor parameter set in sequence, substituting the synchronous motor parameters, historical vertical current and historical parallel current into the original observation model to obtain an observed operating current, wherein the observed operating current includes an observed vertical current and an observed parallel current; The observed operating currents are summarized to obtain an observed operating current set.

[0039] It can be understood that the synchronous parameter detection refers to using a current detector to detect the current of the brushless motor to be tested, while using a voltage detector, a resistance detector and an inductance detector to perform voltage detection, resistance detection and inductance detection on the brushless motor to be tested respectively. The synchronous motor parameter set refers to a collection of synchronous motor parameters. The synchronous motor resistance and the synchronous motor inductance refer to the resistance and inductance of the brushless motor to be tested detected by the voltage detector and the inductance detector respectively. The synchronous vertical voltage and the synchronous parallel voltage refer to the voltage of the brushless motor to be tested perpendicular to the direction of the rotor magnetic field and the voltage parallel to the direction of the rotor magnetic field detected by the voltage detector respectively.

[0040] It should be explained that the zero value refers to the constant zero, the historical vertical current refers to the observed vertical current obtained by the original observation model when the synchronous motor parameters were last collected with reference to the moment when the synchronous motor parameters are currently collected. When the synchronous parameter detection is performed for the first time at this time, the historical vertical current is 0. Similarly, the historical parallel current is the observed parallel current obtained by the last original observation model. The observed vertical current and the observed parallel current respectively refer to the output corresponding to the current vertical current variable and the output corresponding to the current parallel current variable in the original observation model. The observed operating current set refers to the set of observed operating currents.

[0041] S5. Perform observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value, and determine whether the observation error value is greater than a preset minimum error value.

[0042] It should be explained that the observed error value represents the numerical value of the data difference between the observed operating current set and the original operating current set. The larger the data difference between the observed operating current set and the original operating current set, the larger the observed error value is, and the smaller the data difference between the observed operating current set and the original operating current set is, the smaller the observed error value is. The minimum error value refers to the minimum value of the observed error value set manually.

[0043] In detail, performing observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value includes: According to the observed operating current set and the original operating current set, effective current data analysis is performed to obtain an effective current error factor set and an effective fluctuation weight set; Based on the effective current error factor set and the effective fluctuation weight set, the observation error value is calculated using the following formula: in, represents the observation error value, represents the number of effective current error factors in the effective current error factor set or the number of effective fluctuation weights in the effective fluctuation weight set, represents the first The effective volatility weight, Indicates the effective current error factor concentration An effective current error factor.

[0044] It can be understood that the effective current error factor set refers to a set of effective current error factors, wherein the effective current error factor refers to the numerical value of the data difference between the observed operating current and the corresponding original operating current, and the effective fluctuation weight set refers to a set of effective fluctuation weights, wherein the effective fluctuation weight refers to the calculation weight of the effective current error factor when subsequently calculating the observed error value.

[0045] In detail, the effective current data analysis is performed according to the observed operating current set and the original operating current set to obtain an effective current error factor set and an effective fluctuation weight set, including: Recording the time when the step of performing current detection on the brushless motor to be tested based on the current detector is completed; Extracting the observed operating current and the original operating current corresponding to the extracted observed operating current from the observed operating current set and the original operating current set respectively, obtaining the current collection moments of the observed operating current and the original operating current, and calculating the time length fluctuation weight between the detection completion moment and the current collection moment; Calculate the unit current error factor; If it is confirmed that the unit current error factor is not greater than the preset controllable error factor, the unit current error factor and the time fluctuation weight are recorded as the effective current error factor and the effective fluctuation weight respectively; The effective current error factors and effective fluctuation weights are respectively summarized to obtain an effective current error factor set and an effective fluctuation weight set.

[0046] It can be understood that the detection completion moment refers to the moment when the current detection step of the brushless motor to be tested is completed based on the current detector, the current collection moment refers to the moment when the observed operating current and the original operating current are obtained, the duration fluctuation weight refers to the absolute difference between the detection completion moment and the current collection moment, the unit current error factor refers to the numerical value of the data difference between the observed operating current and the original operating current, and the controllable error factor refers to an artificially set error factor constant. When the unit error factor is greater than the controllable error factor, it means that the unit current error factor at this time is too large, resulting in abnormal data, and the unit current error factor cannot be substituted into the subsequent calculation of the observed error value.

[0047] It should be explained that the purpose of introducing the time fluctuation weight in calculating the observation error value is: since the current data collected close to the time when the detection is completed is more in line with the current change trend of the brushless motor to be tested, the unit current error factor at the time of collection close to the time when the detection is completed should be given a higher calculation weight.

[0048] In detail, the calculation of the unit current error factor includes: Based on the observed operating current and the original operating current, a unit current error factor is calculated, wherein the unit current error factor is expressed as: in, represents the unit current error factor, Represents the original vertical current in the original operating current, Represents the observed vertical current in the observed operating current, Represents the original parallel current in the original operating current, Represents the observed parallel current in the observed operating current.

[0049] S6. If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model.

[0050] It can be understood that the adjusted observation model refers to the original observation model after adjustment.

[0051] In detail, the adjusting the original observation model to obtain the adjusted observation model includes: The adjustment amplitude factor is set based on the sampling period, wherein the adjustment amplitude factor is expressed as: Among them, the represents the adjustment amplitude factor, Indicates the preset selection constant; According to the adjustment amplitude factor, the adjustment vertical control factor and the adjustment parallel control factor are calculated using the following formula: in, represents the adjustment of the vertical control factor, represents the adjustment of parallel control factors; The adjusted vertical control factor and the adjusted parallel control factor are used to replace the original vertical control factor and the original parallel control factor in the original observation model respectively, so as to obtain the adjusted observation model.

[0052] It should be explained that the adjustment amplitude factor refers to a manually set value representing the adjustment amplitude when adjusting the original observation model. The larger the adjustment amplitude required by the original observation model, the smaller the adjustment amplitude factor. The smaller the adjustment amplitude required by the original observation model, the larger the adjustment amplitude factor. The value of the adjustment amplitude factor is related to the sampling period. Usually, the value of the adjustment amplitude factor is in integer proportion to the sampling period, that is, the adjustment amplitude factor can be determined by selecting a constant, wherein the selected constant is a manually set constant. When the motor operator hopes that the brushless motor to be tested can quickly complete the rotor position and rotor speed detection, the selected constant can be set to 1. Compared with other selected constants, such as 2 to 9, the adjustment amplitude is larger when the original observation model is adjusted under this selected constant, and thus the adjustment speed is faster. If the motor operator hopes to maintain higher accuracy when detecting the rotor position and rotor speed, the selected constant can be set to 10. Compared with other selected constants, such as 1 to 9, the adjustment amplitude is smaller when the original observation model is adjusted under this selected constant, and the adjustment accuracy is higher.

[0053] S7, taking the adjusted observation model as the original observation model, returning to the step of calculating the state parameters of the brushless motor to be tested using the original observation model, until the observation error value is no greater than the minimum error value, and recording the original observation model at this time as the target observation model.

[0054] It can be understood that the target observation model refers to the original observation model when the observation error value is not less than the minimum error value. When the observation error value is greater than the minimum error value, it means that the error between the parameter observation value obtained by the original observation model at this time and the actual parameter is not within the controllable range. At this time, the original observation model needs to be adjusted to obtain the adjusted observation model. Then, the observation error value of the adjusted observation model needs to be recalculated, that is, the adjusted observation model needs to be used as the original observation model, and the original observation model at this time is substituted into the above-mentioned step of calculating the state parameters of the brushless motor to be tested using the original observation model. When the observation error value is not less than the minimum error value, it means that the parameter observation value obtained by the original observation model at this time can be well matched with the actual parameter, and the original observation model at this time can be used as the observation model for the final calculation of the rotor position angle and rotor speed.

[0055] S8. Calculate the observed rotor position angle and the observed rotor speed according to the target observation model, and complete the position sensorless brushless motor control based on the state observer based on the observed rotor position angle and the observed rotor speed.

[0056] It can be understood that the observed rotor position angle refers to the rotor position angle of the brushless motor to be measured obtained by the target observation model, wherein the rotor position angle refers to the angle between the rotor pole and the stator winding. The observed rotor speed refers to the rotor speed of the brushless motor to be measured obtained by the target observation model, wherein the rotor speed refers to the angular velocity of the rotor when it rotates.

[0057] In detail, the calculating the observed rotor position angle and the observed rotor speed according to the target observation model includes: Identifying a target vertical control factor and a target parallel control factor in the target observation model; Using a preset low-pass filter to extract the vertical back electromotive force in the target vertical control factor and the parallel back electromotive force in the target parallel control factor respectively; According to the vertical back electromotive force and the parallel back electromotive force, the observed rotor position angle and the observed rotor speed are calculated, wherein the observed rotor position angle and the observed rotor speed are respectively expressed as: in, represents the observed rotor position angle, represents the four-quadrant inverse tangent function, represents the vertical back EMF, represents the parallel back EMF, represents the observed rotor speed, Indicates the preset back-EMF constant.

[0058] It can be understood that the target vertical control factor refers to the original vertical control factor in the target observation model, and the target parallel control factor refers to the original parallel control factor in the target observation model. The low-pass filter refers to a signal processing tool that can be used to extract the DC component in the signal, the vertical back EMF refers to the back EMF perpendicular to the direction of the rotor magnetic field, and the parallel back EMF refers to the back EMF parallel to the direction of the rotor magnetic field, wherein the back EMF is an induced voltage generated during the operation of the motor. When the rotor of the motor rotates, its magnetic field will induce a voltage in the stator winding, and this voltage is the back EMF. The back EMF constant refers to a proportional constant, which represents the size of the back EMF generated by the motor per unit speed, and can be queried through the specification of the brushless motor to be tested.

[0059] In order to solve the problem described in the background technology, the present invention first starts a brushless motor to be tested, which does not include a position sensor and a speed sensor, thereby reducing the cost, complexity and failure risk of controlling the brushless motor to be tested. Then, the current detection is performed on the brushless motor to be tested based on a current detector to obtain an original operating current set. This step can obtain the current information of the motor in real time, including vertical current and parallel current, and provide basic data for subsequent state estimation. Then, the resistance, inductance and other parameters in the brushless motor to be tested are detected, and an original observation model of the state observer is constructed based on these parameters. The model can describe the dynamic characteristics of the motor when it is running, and provides a specific calculation method for the subsequent estimation of the rotor position and the rotor speed. Furthermore, the original observation model is used to calculate the state parameters of the brushless motor to be tested, and the state parameters are obtained. The observed operating current set is obtained, and the observed error value between the original operating current set and the observed operating current set is calculated, and the dynamic adjustment of the original observation model is completed based on the observed error value. This adjustment method can gradually adjust the original observation model of the state observer so that the observation model always maintains the optimal state, thereby achieving high-precision tracking of the motor operating state. This method not only improves the accuracy of rotor position and rotor speed detection, but also enhances the stability of motor control. Through the above-mentioned dynamic adjustment mechanism, the target observation model finally obtained can estimate the rotor position angle and speed with high accuracy, especially in the low-speed operation and startup stage. Traditional methods are often difficult to accurately obtain rotor position information. This method can effectively solve this problem by continuously adjusting the original observation model, thereby achieving stable control within the full speed range. Therefore, the present invention can improve the accuracy of rotor parameter detection and the stability of motor control during brushless motor control.

[0060] like Figure 2 , which is a functional module diagram of a position sensorless brushless motor control system based on a state observer provided by an embodiment of the present invention.

[0061] The state observer-based position sensorless brushless motor control system 100 of the present invention can be installed in an electronic device. According to the functions to be implemented, the state observer-based position sensorless brushless motor control system 100 can include an original current acquisition module 101, a motor current observation module 102, an observation model adjustment module 103 and a rotor parameter calculation module 104. The module of the present invention can also be called a unit, which refers to a series of computer program segments that can be executed by an electronic device processor and can complete fixed functions, which are stored in the memory of the electronic device.

[0062] The original current acquisition module 101 is used to receive a motor control instruction, and start the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer, and performs current detection on the brushless motor to be tested based on the current detector to obtain an original operating current set, wherein the original operating current set includes multiple original operating currents, and each original operating current includes an original vertical current and an original parallel current; The motor current observation module 102 is used to construct the original observation model of the state observer, and use the original observation model to calculate the state parameters of the brushless motor to be measured to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; The observation model adjustment module 103 is used to perform observation error analysis according to the observed operating current set and the original operating current set to obtain an observation error value, and determine whether the observation error value is greater than a preset minimum error value. If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The rotor parameter calculation module 104 is used to use the adjusted observation model as the original observation model, return to the step of using the original observation model to calculate the state parameters of the brushless motor to be tested, until the observation error value is no greater than the minimum error value, and record the original observation model at this time as the target observation model, and calculate the observed rotor position angle and the observed rotor speed according to the target observation model.

[0063] In detail, the modules in the position sensorless brushless motor control system 100 based on the state observer in the embodiment of the present invention are used in the same manner as described above. Figure 1 The technical means are the same as the state observer-based position sensorless brushless motor control method described in, and can produce the same technical effects, so they will not be repeated here.

[0064] like Figure 3 , which is a schematic diagram of the structure of an electronic device for implementing a position sensorless brushless motor control method based on a state observer provided by an embodiment of the present invention.

[0065] The electronic device 1 may include a processor 10, a memory 11 and a bus 12, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a position sensorless brushless motor control method program based on a state observer.

[0066] The memory 11 includes at least one type of readable storage medium, and the readable storage medium includes a flash memory, a mobile hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc.), a magnetic memory, a disk, an optical disk, etc. In some embodiments, the memory 11 may be an internal storage unit of the electronic device 1, such as a mobile hard disk of the electronic device 1. In other embodiments, the memory 11 may also be an external storage device of the electronic device 1, such as a plug-in mobile hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device 1. Further, the memory 11 also includes an internal storage unit of the electronic device 1 and an external storage device. The memory 11 can not only be used to store application software and various types of data installed in the electronic device 1, such as the code of the program of the position sensorless brushless motor control method based on the state observer, but also can be used to temporarily store data that has been output or is to be output.

[0067] The processor 10 may be composed of an integrated circuit in some embodiments, for example, a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and combinations of various control chips, etc. The processor 10 is the control core (Control Unit) of the electronic device, and uses various interfaces and lines to connect various components of the entire electronic device, and executes or executes programs or modules stored in the memory 11 (such as a position sensorless brushless motor control method program based on a state observer, etc.), and calls data stored in the memory 11 to execute various functions of the electronic device 1 and process data.

[0068] The bus 12 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 12 may be divided into an address bus, a data bus, a control bus, etc. The bus 12 is configured to realize connection and communication between the memory 11 and at least one processor 10, etc.

[0069] Figure 3 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 3The structure shown does not constitute a limitation on the electronic device 1, and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0070] For example, although not shown, the electronic device 1 may also include a power source (such as a battery) for supplying power to various components. Preferably, the power source may be logically connected to the at least one processor 10 through a power management system, so that the power management system can realize functions such as charging management, discharging management, and power consumption management. The power source may also include any components such as one or more DC or AC power sources, recharging systems, power failure detection circuits, power converters or inverters, and power status indicators. The electronic device 1 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0071] Furthermore, the electronic device 1 may also include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device 1 and other electronic devices.

[0072] Optionally, the electronic device 1 may further include a user interface, which may be a display, an input unit (such as a keyboard), or a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, and an OLED (Organic Light-Emitting Diode) touch device. The display may also be appropriately referred to as a display screen or a display unit, which is used to display information processed in the electronic device 1 and to display a visual user interface.

[0073] The position sensorless brushless motor control method program based on the state observer stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When running in the processor 10, it can achieve: receiving a motor control instruction, and starting the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer; Performing current detection on the brushless motor to be tested based on a current detector to obtain an original operating current set, wherein the original operating current set includes a plurality of original operating currents, and each original operating current includes an original vertical current and an original parallel current; Constructing an original observation model of the state observer; Using the original observation model, the state parameters of the brushless motor to be measured are calculated to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; Performing observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value, and determining whether the observation error value is greater than a preset minimum error value; If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The adjustment observation model is used as the original observation model, and the step of calculating the state parameters of the brushless motor to be tested by using the original observation model is returned until the observation error value is not greater than the minimum error value, and the original observation model at this time is recorded as the target observation model; According to the target observation model, the observed rotor position angle and the observed rotor speed are calculated, and based on the observed rotor position angle and the observed rotor speed, the position sensorless brushless motor control based on the state observer is completed.

[0074] Specifically, the specific implementation method of the processor 10 for the above instructions can refer to Figures 1 to 3 The description of the relevant steps in the corresponding embodiments will not be repeated here.

[0075] Furthermore, if the module / unit integrated in the electronic device 1 is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium can include: any entity or system that can carry the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).

[0076] The present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor of an electronic device, the computer program can implement: receiving a motor control instruction, and starting the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer; Performing current detection on the brushless motor to be tested based on a current detector to obtain an original operating current set, wherein the original operating current set includes a plurality of original operating currents, and each original operating current includes an original vertical current and an original parallel current; Constructing an original observation model of the state observer; Using the original observation model, the state parameters of the brushless motor to be measured are calculated to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; Performing observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value, and determining whether the observation error value is greater than a preset minimum error value; If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The adjustment observation model is used as the original observation model, and the step of calculating the state parameters of the brushless motor to be tested by using the original observation model is returned until the observation error value is not greater than the minimum error value, and the original observation model at this time is recorded as the target observation model; According to the target observation model, the observed rotor position angle and the observed rotor speed are calculated, and based on the observed rotor position angle and the observed rotor speed, the position sensorless brushless motor control based on the state observer is completed.

[0077] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, systems and methods can be implemented in other ways. For example, the system embodiments described above are only illustrative, and actual implementation may have other division methods.

[0078] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0079] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0080] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for controlling a brushless motor without position sensor based on a state observer, characterized in that: The method comprises: receiving a motor control instruction, and starting the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer; Performing current detection on the brushless motor to be tested based on a current detector to obtain an original operating current set, wherein the original operating current set includes a plurality of original operating currents, and each original operating current includes an original vertical current and an original parallel current; Constructing an original observation model of the state observer; Using the original observation model, the state parameters of the brushless motor to be measured are calculated to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; Performing observation error analysis based on the observed operating current set and the original operating current set to obtain an observation error value, and determining whether the observation error value is greater than a preset minimum error value; If the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The adjustment observation model is used as the original observation model, and the step of calculating the state parameters of the brushless motor to be tested by using the original observation model is returned until the observation error value is not greater than the minimum error value, and the original observation model at this time is recorded as the target observation model; According to the target observation model, the observed rotor position angle and the observed rotor speed are calculated, and based on the observed rotor position angle and the observed rotor speed, the position sensorless brushless motor control based on the state observer is completed.

2. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 1, characterized in that: The current detection of the brushless motor to be tested is performed based on a current detector to obtain an original operating current set, including: Under a preset current detection cycle, the current detector is used to monitor the current signal to obtain a continuous operating current, wherein the continuous operating current is a current signal that changes continuously under the current detection cycle; A sampling period of the state observer is obtained, and based on the sampling period, discrete current sampling is performed in the continuous operating current to obtain an original operating current set.

3. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 2, characterized in that: The constructing of the original observation model of the state observer comprises: Setting a current current variable and a historical current variable, wherein the current current variable includes: a current vertical current variable and a current parallel current variable, and the historical current variable includes: a historical vertical current variable and a historical parallel current variable; Based on the sampling period, the current current variable and the historical current variable, an original observation model is constructed, wherein the original observation model is expressed as: in, represents the original observation model, Represents the current vertical current variable, represents the historical vertical current variable, represents the sampling period, represents the preset inductance variable, Represents the preset vertical voltage variable, Represents the preset resistance variable, Represents the preset original vertical control factor, represents the current parallel current variable, represents the historical parallel current variable, Table preset parallel voltage variables, Represents the preset original parallel control factor.

4. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 3, characterized in that: The original observation model is used to calculate the state parameters of the brushless motor to be measured, and the observed operating current set is obtained, including: In the step of performing current detection on the brushless motor to be tested based on the current detector, a voltage detector, a resistance detector and an inductance detector are used to perform synchronous parameter detection on the brushless motor to be tested, so as to obtain a synchronous motor parameter set, wherein the synchronous motor parameter set includes a plurality of synchronous motor parameters, and the synchronous motor parameters include: synchronous motor resistance, synchronous motor inductance, synchronous vertical voltage and synchronous parallel voltage; If the step of performing synchronous parameter detection on the brushless motor to be tested is the first time to perform synchronous parameter detection, the preset zero values ​​are recorded as the historical vertical current and the historical parallel current respectively; If the step of performing synchronous parameter detection on the brushless motor to be tested is not the first time to perform synchronous parameter detection, querying the historical vertical current and the historical parallel current; Extracting synchronous motor parameters in the synchronous motor parameter set in sequence, substituting the synchronous motor parameters, historical vertical current and historical parallel current into the original observation model to obtain an observed operating current, wherein the observed operating current includes an observed vertical current and an observed parallel current; The observed operating currents are summarized to obtain an observed operating current set.

5. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 4, characterized in that: The performing observation error analysis according to the observed operating current set and the original operating current set to obtain the observation error value includes: According to the observed operating current set and the original operating current set, effective current data analysis is performed to obtain an effective current error factor set and an effective fluctuation weight set; Based on the effective current error factor set and the effective fluctuation weight set, the observation error value is calculated using the following formula: in, represents the observation error value, represents the number of effective current error factors in the effective current error factor set or the number of effective fluctuation weights in the effective fluctuation weight set, represents the first The effective volatility weight, Indicates the effective current error factor concentration An effective current error factor.

6. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 5, characterized in that: The effective current data analysis is performed according to the observed operating current set and the original operating current set to obtain an effective current error factor set and an effective fluctuation weight set, including: Recording the time when the step of performing current detection on the brushless motor to be tested based on the current detector is completed; Extracting the observed operating current and the original operating current corresponding to the extracted observed operating current from the observed operating current set and the original operating current set respectively, obtaining the current collection time of the observed operating current and the original operating current, and calculating the time length fluctuation weight between the detection completion time and the current collection time; Calculate the unit current error factor; If it is confirmed that the unit current error factor is not greater than the preset controllable error factor, the unit current error factor and the time fluctuation weight are recorded as the effective current error factor and the effective fluctuation weight respectively; The effective current error factors and effective fluctuation weights are respectively summarized to obtain an effective current error factor set and an effective fluctuation weight set.

7. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 6, characterized in that: The calculating unit current error factor comprises: Based on the observed operating current and the original operating current, a unit current error factor is calculated, wherein the unit current error factor is expressed as: in, represents the unit current error factor, Represents the original vertical current in the original operating current, Represents the observed vertical current in the observed operating current, Represents the original parallel current in the original operating current, Represents the observed parallel current in the observed operating current.

8. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 7, characterized in that: The adjusting the original observation model to obtain the adjusted observation model includes: The adjustment amplitude factor is set based on the sampling period, wherein the adjustment amplitude factor is expressed as: Among them, the represents the adjustment amplitude factor, Indicates the preset selection constant; According to the adjustment amplitude factor, the adjustment vertical control factor and the adjustment parallel control factor are calculated using the following formula: in, represents the adjustment of the vertical control factor, represents the adjustment of parallel control factors; The adjusted vertical control factor and the adjusted parallel control factor are used to replace the original vertical control factor and the original parallel control factor in the original observation model respectively, so as to obtain the adjusted observation model.

9. The method for controlling a brushless motor without position sensor based on a state observer as claimed in claim 8, characterized in that: The step of calculating the observed rotor position angle and the observed rotor speed according to the target observation model comprises: Identifying a target vertical control factor and a target parallel control factor in the target observation model; Using a preset low-pass filter to extract the vertical back electromotive force in the target vertical control factor and the parallel back electromotive force in the target parallel control factor respectively; According to the vertical back electromotive force and the parallel back electromotive force, the observed rotor position angle and the observed rotor speed are calculated, wherein the observed rotor position angle and the observed rotor speed are respectively expressed as: in, represents the observed rotor position angle, represents the four-quadrant inverse tangent function, represents the vertical back EMF, represents the parallel back EMF, represents the observed rotor speed, Indicates the preset back-EMF constant.

10. A position sensorless brushless motor control system based on a state observer, characterized in that: The system comprises: An original current acquisition module is used to receive a motor control instruction, and start the brushless motor to be tested based on the motor control instruction, wherein the brushless motor to be tested has a built-in current detector, a voltage detector, a resistance detector, an inductance detector and a state observer, and performs current detection on the brushless motor to be tested based on the current detector to obtain an original operating current set, wherein the original operating current set includes multiple original operating currents, and each original operating current includes an original vertical current and an original parallel current; A motor current observation module is used to construct an original observation model of the state observer, and to calculate the state parameters of the brushless motor to be measured by using the original observation model to obtain an observed operating current set, wherein the number of observed operating currents in the observed operating current set is the same as the number of original operating currents in the original operating current set; an observation model adjustment module, configured to perform observation error analysis according to the observed operating current set and the original operating current set to obtain an observation error value, and determine whether the observation error value is greater than a preset minimum error value; if the observation error value is greater than the minimum error value, the original observation model is adjusted to obtain an adjusted observation model; The rotor parameter calculation module is used to use the adjusted observation model as the original observation model, return to the step of using the original observation model to calculate the state parameters of the brushless motor to be tested, until the observation error value is no greater than the minimum error value, and record the original observation model at this time as the target observation model, and calculate the observed rotor position angle and the observed rotor speed according to the target observation model.

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