A low-frequency torque compensation control method for synchronous motor

Abstract

The invention discloses a low-frequency torque compensation control method for a synchronous motor, relates to the field of synchronous motors, and solves the problem of inaccurate low-frequency torque judgment of synchronous motors at present. The method comprises: an equipment analysis module performs initial analysis on a target motor, and if an analysis instruction is obtained through analysis, it is sent to a comprehensive prediction module, and if an abnormal signal is obtained through analysis, it is sent to a display terminal; a calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor; the comprehensive prediction module analyzes the power generation status of the target motor, and obtains the estimated electromagnetic torque of the target motor through analysis and sends it to a comprehensive judgment module; the comprehensive judgment module judges the torque compensation degree of the target motor; the control terminal controls and compensates the target motor according to the compensation signal, and the display terminal displays the state of the target motor according to the abnormal signal or the normal signal. The invention accurately judges the low-frequency torque state of the synchronous motor and performs intelligent compensation control.

Description

Technical Field

[0001] The invention belongs to the field of synchronous motors and relates to a torque compensation technology, in particular to a low-frequency torque compensation control method for a synchronous motor. Background Art

[0002] Synchronous motor is a common type of AC motor, and its working principle is based on electromagnetic induction and synchronous rotation of magnetic field. Compared with other types of motors, synchronous motors have advantages such as high efficiency, high power factor and precise speed control, so they are widely used in many application fields. The basic structure of synchronous motor includes stator and rotor. The stator is the fixed part of the motor, usually composed of three-phase windings, which produces a rotating magnetic field. The rotor is the rotating part of the motor, usually composed of permanent magnets or electromagnetic windings, which rotate synchronously with the magnetic field of the stator. When the torque of the synchronous motor is low, it will cause the power generation efficiency to decrease, so it is necessary to compensate for the low-frequency torque of the synchronous motor.

[0003] However, at present, when judging whether a synchronous motor is in low-frequency torque, in most cases, only side information such as final power generation or speed is used to determine whether the synchronous motor is in low-frequency torque, and the specific torque value of the synchronous motor is not calculated, resulting in the inability to accurately judge the degree of low-frequency torque and low frequency; To this end, we propose a low-frequency torque compensation control method for synchronous motors. Summary of the invention

[0004] The purpose of the present invention is to solve the above problems and to propose a low-frequency torque compensation control method for a synchronous motor to solve the problems raised in the above background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A low-frequency torque compensation control method for a synchronous motor, the method is specifically as follows: Step S101, the data acquisition module acquires the real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to the comprehensive prediction module and the calculation module, and sends the motor equipment information of the target motor to the equipment analysis module; Step S102, the equipment analysis module performs an initial analysis on the target motor, and if an analysis instruction is obtained through the analysis, it is sent to the comprehensive prediction module; if an abnormal signal is obtained through the analysis, it is sent to the display terminal; Step S103, the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and sends the grid frequency and the number of motor poles corresponding to the target motor and the stator mutual inductance coefficient corresponding to the stator in the target motor to the comprehensive prediction module; Step S104, the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive determination module; Step S105, the data acquisition module also acquires the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, obtains the estimated electromagnetic torque of the target motor through the analysis and sends it to the comprehensive judgment module; Step S106, the comprehensive determination module determines the torque compensation degree of the target motor, and if a primary compensation signal or a secondary compensation signal is generated, it is sent to the control terminal; if a normal signal is generated, it is sent to the display terminal; Step S107 , the control terminal performs control compensation on the target motor according to the compensation signal, and the display terminal displays the state of the target motor according to the abnormal signal or the normal signal.

[0006] Further, in step S101, the motor equipment information includes the number of motor stators and the motor stator rotation angle corresponding to the target motor, wherein the motor stator rotation angle is specifically the angle between the lines connecting the corresponding left endpoints of different stators and the rotating shaft; The real-time power generation information includes a stator voltage value, a stator current value, and a stator resistance value corresponding to each stator of the target motor.

[0007] Furthermore, the sub-steps of step S102 further include: Obtain the motor equipment information of the target motor, and obtain the number of motor stators and the motor stator angle corresponding to the target motor; The estimated motor stator angle corresponding to the target motor is obtained by dividing the circumference by the number of motor stators; the motor stator angle with the largest angle value is subtracted from the estimated motor stator angle to obtain a first angle difference, and the motor stator angle with the smallest angle value is subtracted from the estimated motor stator angle to obtain a second angle difference; Calculate the average value of the first rotation angle difference and the second rotation angle difference and record it as the motor stator rotation angle difference, and compare the motor stator rotation angle difference with the rotation angle difference threshold; If the motor stator angle difference is greater than or equal to the angle difference threshold, an abnormal signal is generated; If the motor stator angle difference is less than the angle difference threshold, an analysis instruction is generated and a DQ coordinate system corresponding to the target motor is constructed.

[0008] Furthermore, the calculation process of the calculation module in step S104 is specifically as follows: Acquire the real-time power generation information of the target motor, and obtain the stator current value DLn and the stator resistance value DZn corresponding to the target motor; wherein n is the number of the stator in the target motor; Obtain the grid frequency PL and the number of motor poles JDS corresponding to the target motor; The calculated stator torque of each stator of the target motor is calculated by the formula, which is as follows: JZJn=1.5×π×PL×JDS×DLn×DZn×λ1, where λ1 is the usage compensation coefficient, 0<λ1≤1, the longer the target motor is used, the smaller the usage compensation coefficient; The calculated stator torque corresponding to each stator of the target motor is added and summed to obtain the calculated electromagnetic torque of the target motor.

[0009] Furthermore, the analysis process of the comprehensive prediction module in step S105 is specifically as follows: Acquire the real-time power generation information of the target motor, and obtain the stator voltage value DYn, stator current value DLn and stator resistance value DZn corresponding to each stator of the target motor; Establish the abc three-phase coordinate system, project the stator current value of the target motor corresponding to the stator into the abc three-phase coordinate system, and obtain the stator three-phase currents DLn1, DLn2 and DLn3 corresponding to the stator; project the stator voltage value of the target motor corresponding to the stator into the abc three-phase coordinate system to obtain the stator three-phase voltages DYn1, DYn2 and DYn3 corresponding to the stator, where 1, 2, and 3 represent the first phase, the second phase, and the third phase, respectively; The stator three-phase voltage is expressed as (1), where , as well as They are the flux linkages of the three-phase windings; (2), where λ is the flux compensation coefficient, 1<λ<1.5, L1, L2 and L3 are the three-phase winding self-inductance coefficients, M is the stator mutual inductance coefficient, M12 represents the mutual inductance coefficient of the first phase to the second phase corresponding to the three-phase electricity in the stator, M13 represents the mutual inductance coefficient of the first phase to the third phase corresponding to the three-phase electricity in the stator, M21 represents the mutual inductance coefficient of the second phase to the first phase corresponding to the three-phase electricity in the stator, and the same applies to M23, M31 and M32. Indicates the radian value of the motor rotor position; Establish the α-β two-phase stationary coordinate system, where α coincides with the a-axis and β is 90° to the a-axis. ； The stator three-phase current in the abc three-phase shaft system is converted into a two-phase current expression in the α-β two-phase stationary coordinate system. The specific conversion formula is: (3); where DLn0 represents the zero-sequence component, T1 is the Clark transformation matrix; The stator voltage value of each stator in the α-β two-phase stationary coordinate system is obtained by combining equations (1), (2) and (3): (4); (5); where DYnα is the component of the stator voltage value on the α axis, DYnβ is the component of the stator voltage value on the β axis, DLnα is the component of the stator current value on the α axis, DLnβ is the component of the stator current value on the β axis, is the component of the stator flux in the α axis, is the component of the stator flux in the β axis, L is the first inductance, and LC is the second inductance.

[0010] Furthermore, in step S105, the analysis process of the comprehensive prediction module further includes: The stator current value in the α-β two-phase stationary coordinate system is converted into the stator current value in the DQ coordinate system by the formula: ; Wherein, T2 is the Park transformation matrix; By performing Park transformation on formula (5), we can obtain: (6); (7); In the above formula, DLnd is the component of the stator current value on the D axis, DLnq is the component of the stator current value on the Q axis, DYnd is the component of the stator voltage value on the D axis, DYnq is the component of the stator voltage value on the Q axis, is the component of the stator flux in the D axis, is the component of the stator flux on the Q axis, ω e is the angular velocity of the rotor magnetic field, Ld is the inductance corresponding to the D axis, and Lq is the inductance corresponding to the Q axis; Substituting equation (7) into equation (6) yields the stator voltage value of the target motor corresponding to the stator in the DQ coordinate system: (8); The estimated stator torque of the corresponding stator is calculated by the formula, which is as follows: ; The estimated stator torques corresponding to all stators are added together to calculate the estimated electromagnetic torque of the target motor.

[0011] Furthermore, the Clark transformation matrix T1 is specifically: ; The Park transformation matrix T2 is specifically: .

[0012] Furthermore, in step S106, the identification process of the comprehensive identification module is as follows: Obtaining the estimated electromagnetic torque and calculated electromagnetic torque corresponding to the target motor; The calculated electromagnetic torque is compared with the estimated electromagnetic torque, and if the calculated electromagnetic torque is greater than or equal to the estimated electromagnetic torque, a normal signal is generated; If the calculated electromagnetic torque is less than the estimated electromagnetic torque, the motor torque compensation value is obtained by subtracting the calculated electromagnetic torque from the estimated electromagnetic torque; If the motor torque compensation value is less than or equal to the first compensation threshold, a normal signal is generated; If the motor torque compensation value is greater than the first compensation threshold and less than or equal to the second compensation threshold, a primary compensation signal is generated; If the motor torque compensation value is greater than the second compensation threshold, a secondary compensation signal is generated.

[0013] Furthermore, the compensation strength of the secondary compensation signal corresponding to the target motor is greater than the compensation strength of the primary compensation signal corresponding to the target motor.

[0014] Furthermore, in step S107, the control compensation of the control terminal is specifically: If the received signal is a first-level compensation signal, the motor torque compensation value is obtained, and the corresponding parameters of the inverter of the target motor are set according to the motor torque compensation value to ensure that the calculated electromagnetic torque is greater than the estimated electromagnetic torque; If the received signal is a secondary compensation signal, the motor parameters corresponding to the target motor are adjusted.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: The present invention uses an equipment analysis module to perform an initial analysis on the target motor. If an analysis instruction is obtained through the analysis, it is sent to a comprehensive prediction module. If an abnormal signal is obtained through the analysis, it is sent to a display terminal. At the same time, the calculated electromagnetic torque corresponding to each stator in the target motor is calculated through a calculation module, and the calculated electromagnetic torque of the target motor is sent to a comprehensive discrimination module. On the other hand, the comprehensive prediction module analyzes the power generation status of the target motor, and the estimated electromagnetic torque of the target motor is sent to the comprehensive discrimination module. Finally, the torque compensation degree of the target motor is judged through the comprehensive discrimination module. If a primary compensation signal or a secondary compensation signal is generated, it is sent to a control terminal. If a normal signal is generated, it is sent to a display terminal. The control terminal controls and compensates the target motor according to the compensation signal. At the same time, the display terminal displays the state of the target motor according to the abnormal signal or the normal signal. The present invention accurately judges the low-frequency torque state of the synchronous motor and performs intelligent compensation control. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0017] Figure 1 It is a schematic diagram of the method of the present invention; Figure 2 A schematic diagram of a system involved in the present invention; Figure 3 Schematic diagram of the target motor in the present invention; Figure 4 Schematic diagram of the DQ coordinate system in the target motor of the present invention; Figure 5 It is a schematic diagram of the abc three-phase coordinates in the present invention; Figure 6 It is a schematic diagram of comprehensive coordinates in the present invention; Figure 7 The present invention is a schematic diagram of an electronic device. DETAILED DESCRIPTION

[0018] The technical scheme of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Example 1: Please refer to Figure 1-Figure 6 As shown, the technical solution provided by the present invention is: a low-frequency torque compensation control method for a synchronous motor, wherein the synchronous motor is composed of a stator, a rotor, a rotating shaft and bearings, wherein the rotor is a permanent magnet with magnetism, and can generate a constant rotor magnetic field, and a stator winding coil is wound on the stator. When AC is passed into the stator winding coil, the stator winding coil will generate a stator magnetic field and corresponding magnetic flux lines, and the stator magnetic field and the rotor magnetic field interact to generate torque, and the torque drives the rotor to rotate, so that the rotor magnetic field rotates to cut the magnetic flux lines corresponding to the stator magnetic field and generate an induced electromotive force (induced voltage), thereby realizing the ability to generate electricity; for the convenience of explanation, in this embodiment, the synchronous motor is defined as a target motor, and the target motor is identified as an ideal motor, and the ideal motor meets the following conditions: ignoring the eddy current and hysteresis loss of the motor; ignoring the core saturation effect of the stator and rotor of the motor; when the motor is running stably, the current waveform of the three-phase winding is a standard sine wave; the conductivity of the permanent magnetic material is zero, and its internal magnetic permeability is assumed to be the same as the magnetic permeability of air; In this embodiment, the synchronous motor low-frequency torque compensation control method is specifically as follows: Step S101, the data acquisition module acquires the real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to the comprehensive prediction module and the calculation module, and sends the motor equipment information of the target motor to the equipment analysis module; See also Figure 3As shown, the motor equipment information includes the number of motor stators and the motor stator angle corresponding to the target motor, wherein the motor stator angle is specifically the angle between the lines connecting the left endpoints of different stators and the rotating shaft. It should be noted that the motor stator angle can be regarded as the angle between two motor stators, so the number of motor stator angles is the same as the number of motor stators. If the number of motor stators is M, the number of motor stator angles is also M; The real-time power generation information includes the stator voltage value, stator current value and stator resistance value of each stator of the target motor; Step S102, the equipment analysis module performs an initial analysis on the target motor, and if an analysis instruction is obtained through the analysis, it is sent to the comprehensive prediction module; if an abnormal signal is obtained through the analysis, it is sent to the display terminal; In step S102, the analysis process of the device analysis module is as follows: Obtain the motor equipment information of the target motor, and obtain the motor stator number DZS and the motor stator angle DZJ corresponding to the target motor; Then, the estimated motor stator angle corresponding to the target motor is obtained by dividing the circumference by the number of motor stators; the first angle difference is obtained by subtracting the estimated motor stator angle from the motor stator angle with the largest angle value, and the second angle difference is obtained by subtracting the motor stator angle with the smallest angle value from the estimated motor stator angle; Calculate the average value of the first rotation angle difference and the second rotation angle difference and record it as the motor stator rotation angle difference, compare the motor stator rotation angle difference with the rotation angle difference threshold, and if the motor stator rotation angle difference is greater than or equal to the rotation angle difference threshold, generate an abnormal signal, identify the target motor as a faulty motor, and no torque compensation is required; like Figure 3 As shown, if the motor stator angle difference is less than the angle difference threshold, an analysis instruction is generated to construct the DQ coordinate system corresponding to the target motor, wherein the Q axis is also called the quadrature-axis, and the Q axis is perpendicular to the line connecting the N pole and the S pole of the rotor permanent magnet, and the D axis is also called the direct-axis, and the D axis is parallel to the line connecting the N pole and the S pole of the rotor permanent magnet; Step S103, the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and sends the grid frequency and the number of motor poles corresponding to the target motor and the stator mutual inductance coefficient corresponding to the stator in the target motor to the comprehensive prediction module; The database is used to store the grid frequency corresponding to the target motor, the number of motor poles, and the stator mutual inductance coefficient corresponding to the stator in the target motor. The stator mutual inductance coefficient is a measure of the mutual inductance relationship between different windings, which indicates the ratio of the induced electromotive force or current generated in another winding when the current in one winding changes; the grid frequency refers to the periodic change frequency of the voltage or current in the AC power supply system; and the number of motor poles refers to the number of N and S magnetic poles generated by each set of coils of the three-phase AC motor. The number of magnetic poles contained in each phase of each motor is the number of motor poles. Since the magnetic poles appear in pairs, the value of the number of motor poles is an even number; Step S104, the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive determination module; The calculation process of the calculation module is as follows: Acquire the real-time power generation information of the target motor, and obtain the stator current value DLn and the stator resistance value DZn corresponding to the target motor, where n is the number of the stator in the target motor; Obtain the grid frequency PL and the number of motor poles JDS corresponding to the target motor; The calculated stator torque of each stator of the target motor is calculated by the formula, which is as follows: JZJn=1.5×π×PL×JDS×DLn×DZn×λ1, where λ1 is the usage compensation coefficient, 0<λ1≤1, the longer the target motor is used, the smaller the usage compensation coefficient; The calculated stator torque corresponding to each stator of the target motor is added and summed to obtain the calculated electromagnetic torque of the target motor; Step S105, the data acquisition module also acquires the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, obtains the estimated electromagnetic torque of the target motor through the analysis and sends it to the comprehensive judgment module; During the specific collection, the instantaneous rotation speed of the rotor corresponding to the target motor can be collected and obtained by 2π×instantaneous rotation speed / number of motor poles; In step S105, the analysis process of the comprehensive prediction module is as follows: Acquire the real-time power generation information of the target motor, and obtain the stator voltage value DYn, stator current value DLn and stator resistance value DZn corresponding to each stator of the target motor; Establish the abc three-phase coordinate system, project the stator current value of the stator corresponding to the target motor onto the abc three-phase coordinate system, and obtain the stator three-phase currents DLn1, DLn2 and DLn3 corresponding to the stator. Similarly, project the stator voltage value of the stator corresponding to the target motor onto the abc three-phase coordinate system to obtain the stator three-phase voltages DYn1, DYn2 and DYn3 corresponding to the stator, where 1, 2, and 3 represent the first phase, the second phase, and the third phase, respectively. When explaining the attached figures later, only the stator current value is used as an example for explanation; The stator three-phase voltage can be expressed as (1), where , as well as They are the flux linkages of the three-phase windings; (2), where λ is the flux compensation coefficient, 1<λ<1.5, L1, L2 and L3 are the three-phase winding self-inductance coefficients, M is the stator mutual inductance coefficient, M12 represents the mutual inductance coefficient of the first phase to the second phase corresponding to the three-phase electricity in the stator, M13 represents the mutual inductance coefficient of the first phase to the third phase corresponding to the three-phase electricity in the stator, M21 represents the mutual inductance coefficient of the second phase to the first phase corresponding to the three-phase electricity in the stator, and the same applies to M23, M31 and M32. Indicates the radian value of the motor rotor position, that is Figure 6 The angle between the a-axis and the D-axis; Establish the α-β two-phase stationary coordinate system, in which α coincides with the a-axis and β is 90° to the a-axis; The stator three-phase current in the abc three-phase shaft system is converted into a two-phase current expression in the α-β two-phase stationary coordinate system. The specific conversion formula is: (3), where DLn0 represents the zero-sequence component, T1 is the Clark transformation matrix. For example, the Clark transformation matrix is ; By combining (1), (2) and (3), the stator voltage value of each stator in the α-β two-phase stationary coordinate system is obtained as follows: (4); (5); Among them, DYnα is the component of the stator voltage value on the α axis, DYnβ is the component of the stator voltage value on the β axis, DLnα is the component of the stator current value on the α axis, DLnβ is the component of the stator current value on the β axis, is the component of the stator flux in the α axis, is the component of the stator flux in the β axis, L is the first inductance, and LC is the second inductance; The stator current value in the α-β two-phase stationary coordinate system is converted into the stator current value in the DQ coordinate system by the formula: , where T2 is the Park transformation matrix. Exemplarily, the Park transformation matrix can be ; By performing Park transformation on formula (5), we can obtain: (6); (7); In the above formula, DLnd is the component of the stator current value on the D axis, DLnq is the component of the stator current value on the Q axis, DYnd is the component of the stator voltage value on the D axis, DYnq is the component of the stator voltage value on the Q axis, is the component of the stator flux in the D axis, is the component of the stator flux on the Q axis, ω e is the angular velocity of the rotor magnetic field, Ld is the inductance corresponding to the D axis, and Lq is the inductance corresponding to the Q axis; Substituting equation (7) into equation (6) yields the stator voltage value of the target motor corresponding to the stator in the DQ coordinate system: (8); The estimated stator torque of the corresponding stator is calculated by the formula, which is as follows: ; The estimated stator torques corresponding to all stators are added together to calculate the estimated electromagnetic torque of the target motor; Step S106, the comprehensive determination module determines the torque compensation degree of the target motor, and if a primary compensation signal or a secondary compensation signal is generated, it is sent to the control terminal; if a normal signal is generated, it is sent to the display terminal; In step S106, the determination process of the comprehensive determination module is as follows: Obtaining the estimated electromagnetic torque and calculated electromagnetic torque corresponding to the target motor; The calculated electromagnetic torque is compared with the estimated electromagnetic torque. If the calculated electromagnetic torque is greater than or equal to the estimated electromagnetic torque, a normal signal is generated, and it is determined that the torque of the target motor does not need to be compensated. If the calculated electromagnetic torque is less than the estimated electromagnetic torque, the motor torque compensation value is obtained by subtracting the calculated electromagnetic torque from the estimated electromagnetic torque; If the motor torque compensation value is less than or equal to the first compensation threshold, a normal signal is generated to determine that the target motor torque deviation is within an acceptable range; If the motor torque compensation value is greater than the first compensation threshold and less than or equal to the second compensation threshold, a first-level compensation signal is generated, indicating that the torque of the target motor is low and needs slight compensation; If the motor torque compensation value is greater than the second compensation threshold, a secondary compensation signal is generated to identify the target motor torque and require greater compensation; Step S107, the control terminal performs control compensation on the target motor according to the compensation signal, and the display terminal displays the state of the target motor according to the abnormal signal or the normal signal; In step S107, the control compensation of the control terminal is specifically: If the received signal is a first-level compensation signal, the motor torque compensation value is obtained, and the corresponding parameters of the inverter of the target motor are set according to the motor torque compensation value to ensure that the calculated electromagnetic torque is greater than the estimated electromagnetic torque; If the received signal is a secondary compensation signal, the motor parameters corresponding to the target motor are adjusted, including adjusting the rotor impedance and rotor time constant of the motor, so as to improve the response speed and torque capacity of the motor, so as to ensure that the calculated electromagnetic torque is greater than the estimated electromagnetic torque.

[0020] In practice, after the display terminal obtains the abnormal signal or normal signal of the target motor, the user can learn the state of the target motor by reading the abnormal signal or normal signal; In this application, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficient and the proportional coefficient can be determined as long as it does not affect the proportional relationship between the parameter and the result value.

[0021] Embodiment 2: Figure 7An example of a physical structure diagram of an electronic device is provided, and the electronic device may include: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus. The processor may call the logic instructions in the memory to execute a synchronous motor low-frequency torque compensation control method, and the method includes: a data acquisition module acquires the real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to the comprehensive prediction module and the calculation module, and sends the motor equipment information of the target motor to the equipment analysis module; the equipment analysis module performs an initial analysis on the target motor, and if the analysis obtains an analysis instruction, it is sent to the comprehensive prediction module, and if the analysis obtains an abnormal signal, it is sent to the display terminal; the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and at the same time sends the grid frequency, the number of motor poles, and the stator mutual inductance coefficient corresponding to the stator in the target motor to the comprehensive prediction module. Module; the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive judgment module; the data acquisition module also collects the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, and obtains the estimated electromagnetic torque of the target motor through analysis and sends it to the comprehensive judgment module; the comprehensive judgment module judges the torque compensation degree of the target motor, and if the judgment generates a primary compensation signal or a secondary compensation signal, it is sent to the control terminal, and if the judgment generates a normal signal, it is sent to the display terminal; the control terminal controls and compensates the target motor according to the compensation signal, and the display terminal displays the status of the target motor according to the abnormal signal or the normal signal.

[0022] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0023] On the other hand, the present application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute a synchronous motor low-frequency torque compensation control method provided by the above methods, the method comprising: a data acquisition module acquires real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to a comprehensive prediction module and a calculation module, and sends the motor equipment information of the target motor to an equipment analysis module; the equipment analysis module performs an initial analysis on the target motor, and if the analysis obtains an analysis instruction, it is sent to the comprehensive prediction module, and if the analysis obtains an abnormal signal, it is sent to a display terminal; the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and at the same time sends the target motor to the comprehensive prediction module and the calculation module. The corresponding grid frequency, number of motor poles and stator mutual inductance coefficient corresponding to the stator in the target motor are sent to the comprehensive prediction module; the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive judgment module; the data acquisition module also collects the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, analyzes and obtains the estimated electromagnetic torque of the target motor and sends it to the comprehensive judgment module; the comprehensive judgment module judges the torque compensation degree of the target motor, if it is judged that a primary compensation signal or a secondary compensation signal is generated, it is sent to the control terminal, if it is judged that a normal signal is generated, it is sent to the display terminal; the control terminal controls and compensates the target motor according to the compensation signal, and the display terminal displays the status of the target motor according to the abnormal signal or the normal signal.

[0024] On the other hand, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute a synchronous motor low-frequency torque compensation control method provided above, the method comprising: a data acquisition module acquires real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to a comprehensive prediction module and a calculation module, and sends the motor equipment information of the target motor to an equipment analysis module; the equipment analysis module performs an initial analysis on the target motor, and if the analysis obtains an analysis instruction, it is sent to the comprehensive prediction module, and if the analysis obtains an abnormal signal, it is sent to a display terminal; the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and at the same time sends the grid frequency, the number of motor poles and the target motor corresponding to the target motor to the calculation module. The stator mutual inductance coefficient corresponding to the stator in the target motor is sent to the comprehensive prediction module; the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive judgment module; the data acquisition module also collects the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, and obtains the estimated electromagnetic torque of the target motor through analysis and sends it to the comprehensive judgment module; the comprehensive judgment module judges the torque compensation degree of the target motor, if it is judged that a primary compensation signal or a secondary compensation signal is generated, it is sent to the control terminal, if it is judged that a normal signal is generated, it is sent to the display terminal; the control terminal controls and compensates the target motor according to the compensation signal, and the display terminal displays the state of the target motor according to the abnormal signal or the normal signal.

[0025] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0026] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A low-frequency torque compensation control method for a synchronous motor, characterized in that: The specific method is as follows: Step S101, the data acquisition module acquires the real-time power generation information and motor equipment information of the target motor, sends the real-time power generation information of the target motor to the comprehensive prediction module and the calculation module, and sends the motor equipment information of the target motor to the equipment analysis module; Step S102, the equipment analysis module performs an initial analysis on the target motor, and if an analysis instruction is obtained through the analysis, it is sent to the comprehensive prediction module; if an abnormal signal is obtained through the analysis, it is sent to the display terminal; Step S103, the database sends the grid frequency and the number of motor poles corresponding to the target motor to the calculation module, and sends the grid frequency and the number of motor poles corresponding to the target motor and the stator mutual inductance coefficient corresponding to the stator in the target motor to the comprehensive prediction module; Step S104, the calculation module calculates the calculated electromagnetic torque corresponding to each stator in the target motor, and sends the calculated electromagnetic torque of the target motor to the comprehensive determination module; Step S105, the data acquisition module also acquires the angular velocity of the rotor magnetic field rotation corresponding to the target motor and sends it to the comprehensive prediction module, the comprehensive prediction module analyzes the power generation status of the target motor, obtains the estimated electromagnetic torque of the target motor through the analysis and sends it to the comprehensive judgment module; Step S106, the comprehensive determination module determines the torque compensation degree of the target motor, and if a primary compensation signal or a secondary compensation signal is generated, it is sent to the control terminal; if a normal signal is generated, it is sent to the display terminal; Step S107 , the control terminal performs control compensation on the target motor according to the compensation signal, and the display terminal displays the state of the target motor according to the abnormal signal or the normal signal.

2. A synchronous motor low-frequency torque compensation control method according to claim 1, characterized in that: In step S101, the motor equipment information includes the number of motor stators and the motor stator rotation angle corresponding to the target motor, wherein the motor stator rotation angle is specifically the angle between the lines connecting the corresponding left endpoints of different stators and the rotating shaft; The real-time power generation information includes a stator voltage value, a stator current value, and a stator resistance value corresponding to each stator of the target motor.

3. A synchronous motor low-frequency torque compensation control method according to claim 1, characterized in that: The sub-steps of step S102 further include: Obtain the motor equipment information of the target motor, and obtain the number of motor stators and the motor stator angle corresponding to the target motor; The estimated motor stator angle corresponding to the target motor is obtained by dividing the circumference by the number of motor stators; the motor stator angle with the largest angle value is subtracted from the estimated motor stator angle to obtain a first angle difference, and the motor stator angle with the smallest angle value is subtracted from the estimated motor stator angle to obtain a second angle difference; Calculate the average value of the first rotation angle difference and the second rotation angle difference and record it as the motor stator rotation angle difference, and compare the motor stator rotation angle difference with the rotation angle difference threshold; If the motor stator angle difference is greater than or equal to the angle difference threshold, an abnormal signal is generated; If the motor stator angle difference is less than the angle difference threshold, an analysis instruction is generated and a DQ coordinate system corresponding to the target motor is constructed.

4. A synchronous motor low-frequency torque compensation control method according to claim 1, characterized in that: The calculation process of the calculation module in step S104 is as follows: Acquire the real-time power generation information of the target motor, and obtain the stator current value DLn and the stator resistance value DZn corresponding to the target motor; wherein n is the number of the stator in the target motor; Obtain the grid frequency PL and the number of motor poles JDS corresponding to the target motor; The calculated stator torque of each stator of the target motor is calculated by the formula, which is as follows: JZJn=1.5×π×PL×JDS×DLn×DZn×λ1, where λ1 is the usage compensation coefficient, 0<λ1≤1, the longer the target motor is used, the smaller the usage compensation coefficient; The calculated stator torque corresponding to each stator of the target motor is added and summed to obtain the calculated electromagnetic torque of the target motor.

5. The method for low-frequency torque compensation control of a synchronous motor according to claim 1, characterized in that: The analysis process of the comprehensive prediction module in step S105 is as follows: Acquire the real-time power generation information of the target motor, and obtain the stator voltage value DYn, stator current value DLn and stator resistance value DZn corresponding to each stator of the target motor; Establish the abc three-phase coordinate system, project the stator current value of the target motor corresponding to the stator into the abc three-phase coordinate system, and obtain the stator three-phase currents DLn1, DLn2 and DLn3 corresponding to the stator; project the stator voltage value of the target motor corresponding to the stator into the abc three-phase coordinate system to obtain the stator three-phase voltages DYn1, DYn2 and DYn3 corresponding to the stator, where 1, 2, and 3 represent the first phase, the second phase, and the third phase, respectively; The stator three-phase voltage is expressed as (1), where , as well as They are the flux linkage of the three-phase windings; (2), where λ is the flux compensation coefficient, 1<λ<1.5, L1, L2 and L3 are the three-phase winding self-inductance coefficients, M is the stator mutual inductance coefficient, M12 represents the mutual inductance coefficient of the first phase to the second phase corresponding to the three-phase electricity in the stator, M13 represents the mutual inductance coefficient of the first phase to the third phase corresponding to the three-phase electricity in the stator, M21 represents the mutual inductance coefficient of the second phase to the first phase corresponding to the three-phase electricity in the stator, and the same applies to M23, M31 and M32. Indicates the radian value of the motor rotor position; Establish the α-β two-phase stationary coordinate system, where α coincides with the a-axis and β is 90° to the a-axis. ； The stator three-phase current in the abc three-phase shaft system is converted into a two-phase current expression in the α-β two-phase stationary coordinate system. The specific conversion formula is: (3); where DLn0 represents the zero-sequence component, T1 is the Clark transformation matrix; The stator voltage value of each stator in the α-β two-phase stationary coordinate system is obtained by combining equations (1), (2) and (3): （4）； (5); where DYnα is the component of the stator voltage value on the α axis, DYnβ is the component of the stator voltage value on the β axis, DLnα is the component of the stator current value on the α axis, DLnβ is the component of the stator current value on the β axis, is the component of the stator flux in the α axis, is the component of the stator flux in the β axis, L is the first inductance, and LC is the second inductance.

6. A synchronous motor low-frequency torque compensation control method according to claim 5, characterized in that: The analysis process of the comprehensive prediction module in step S105 also includes: The stator current value in the α-β two-phase stationary coordinate system is converted into the stator current value in the DQ coordinate system by the formula: ; Wherein, T2 is the Park transformation matrix; By performing Park transformation on formula (5), we can obtain: （6）； （7）； In the above formula, DLnd is the component of the stator current value on the D axis, DLnq is the component of the stator current value on the Q axis, DYnd is the component of the stator voltage value on the D axis, DYnq is the component of the stator voltage value on the Q axis, is the component of the stator flux in the D axis, is the component of the stator flux on the Q axis, ω e is the angular velocity of the rotor magnetic field, Ld is the inductance corresponding to the D axis, and Lq is the inductance corresponding to the Q axis; Substituting equation (7) into equation (6) yields the stator voltage value of the target motor corresponding to the stator in the DQ coordinate system: （8）； The estimated stator torque of the corresponding stator is calculated by the formula, which is as follows: ； The estimated stator torques corresponding to all stators are added together to calculate the estimated electromagnetic torque of the target motor.

7. A synchronous motor low-frequency torque compensation control method according to claim 6, characterized in that: The Clark transformation matrix T1 is specifically: ; The Park transformation matrix T2 is specifically: .

8. A synchronous motor low-frequency torque compensation control method according to claim 1, characterized in that: In step S106, the identification process of the comprehensive identification module is as follows: Obtaining the estimated electromagnetic torque and calculated electromagnetic torque corresponding to the target motor; The calculated electromagnetic torque is compared with the estimated electromagnetic torque, and if the calculated electromagnetic torque is greater than or equal to the estimated electromagnetic torque, a normal signal is generated; If the calculated electromagnetic torque is less than the estimated electromagnetic torque, the motor torque compensation value is obtained by subtracting the calculated electromagnetic torque from the estimated electromagnetic torque; If the motor torque compensation value is less than or equal to the first compensation threshold, a normal signal is generated; If the motor torque compensation value is greater than the first compensation threshold and less than or equal to the second compensation threshold, a primary compensation signal is generated; If the motor torque compensation value is greater than the second compensation threshold, a secondary compensation signal is generated.

9. A synchronous motor low-frequency torque compensation control method according to claim 7, characterized in that: The compensation strength of the secondary compensation signal corresponding to the target motor is greater than the compensation strength of the primary compensation signal corresponding to the target motor.

10. A synchronous motor low-frequency torque compensation control method according to claim 1, characterized in that: In step S107, the control compensation of the control terminal is specifically: If the received signal is a first-level compensation signal, the motor torque compensation value is obtained, and the corresponding parameters of the inverter of the target motor are set according to the motor torque compensation value to ensure that the calculated electromagnetic torque is greater than the estimated electromagnetic torque; If the received signal is a secondary compensation signal, the motor parameters corresponding to the target motor are adjusted.

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