Motor torque optimization method and device, electronic equipment and storage medium

Abstract

The invention discloses a motor torque optimization method and device, electronic equipment and a storage medium. The method comprises the following steps: acquiring a pre-configured coordinate information matrix; screening the coordinate information matrix based on a preset rotating speed point, a preset torque and a preset formula to obtain a direct-axis current and quadrature-axis current combination meeting a voltage constraint condition; in the direct-axis current and quadrature-axis current combinations meeting the voltage constraint conditions, determining the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal working point; and traversing the preset rotating speed points and the preset torques, and iteratively calculating the coordinate information matrix to obtain optimal working points under different preset rotating speed points and different preset torques. The equal torque line information is obtained through calculation, the expected optimal point is calculated and screened out from the equal torque line information, calibration for different rotating speed points and torque points on the rack is not needed, re-calibration for multiple voltages on the rack is not needed, the workload and time are reduced, and chip resources are saved.

Description

Technical Field

[0001] The present disclosure relates to the field of motor control technology, and in particular to a motor torque optimization method and device, electronic equipment, and storage medium. Background Art

[0002] See also Figure 1 , Figure 1 A classic motor control block diagram provided in the embodiment of the present application, such as Figure 1 As shown in the field-oriented control (foc) control block diagram of the permanent magnet synchronous motor, the torque command Need to be converted into current command and The conversion process is usually implemented by a table lookup method, in which the table data represents the accurate correspondence between the torque command and the current command. Generally, it is necessary to calibrate the motor on a special test bench under different DC side voltages, different motor speeds, and different torque conditions to traverse the stator current synthesis vector and the angle between the stator current synthesis vector and the d-axis, and consider the control strategy of the maximum torque current ratio and the limitation of the inverter voltage to calibrate and obtain the table. This method has a large workload and takes a lot of time, and the calibration accuracy depends on the calibration personnel. Summary of the invention

[0003] The present disclosure provides a motor torque optimization method, device, electronic device and storage medium, which are mainly intended to solve the problem that the calibration method has a large workload, requires a lot of time, and the accuracy depends on the calibration personnel.

[0004] According to a first aspect of the present disclosure, a motor torque optimization method is provided, comprising: Acquire a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a corresponding relationship between torque and a combination of direct-axis current and quadrature-axis current; The coordinate information matrix is ​​screened based on a preset speed point, a preset torque and a preset formula to obtain a combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition; In the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, based on the maximum torque current ratio control strategy, confirming the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal operating point; The preset speed points and the preset torques are traversed, and the coordinate information matrix is ​​iteratively calculated to obtain the optimal working point under different preset speed points and different preset torques.

[0005] Optionally, the coordinate information matrix is ​​screened based on a preset speed point, a preset torque and a preset formula to obtain the direct-axis current and quadrature-axis current combination that satisfies the voltage constraint condition, including: Storing at least one of the preset speed points and at least one of the preset torque points into a preset array; Selecting a target preset speed point and a target torque point in the preset array; Performing torque cycle calculation on the preset torque point based on the target speed point to obtain the direct-axis current and quadrature-axis current combination corresponding to the target preset speed point and the preset torque point; Circularly calculating at least one of the preset speed points and at least one of the preset torque points in the preset array to obtain the direct-axis current and quadrature-axis current combinations corresponding to different preset speed points and different preset torque points; Calculating the stator current synthesis vector and the supply voltage respectively according to different combinations of the direct-axis current and the quadrature-axis current; The stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current are screened based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination that meets the voltage constraint condition.

[0006] Optionally, among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, confirming the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal operating point based on the maximum torque current ratio control strategy includes: In the non-weakening magnetic field region, confirming that the combination of the direct-axis current and the quadrature-axis current at which the stator current is the minimum value is the optimal operating point; In the weak magnetic field region, the combination of the direct-axis current and the quadrature-axis current corresponding to the stator current that meets the inverter voltage restriction condition and has the highest voltage utilization rate is determined as the optimal operating point.

[0007] Optionally, before obtaining the pre-configured coordinate information matrix, the method further includes: The torque matrix is ​​calculated based on a preset torque formula and motor parameters of the target controlled motor.

[0008] Optionally, performing torque cycle calculation on the preset torque point based on the target speed point includes: The isotorque line coordinate information of the preset torque point calculated in the current cycle is obtained, and the stator current synthetic vector and the supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the isotorque line coordinate information.

[0009] Optionally, the screening of the stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination satisfying the voltage constraint condition further includes: When it is determined that there is no combination of the direct-axis current and the quadrature-axis current that satisfies the voltage constraint condition, the preset rotation speed and the preset torque point are re-acquired to perform torque cycle calculation.

[0010] Optionally, storing the correspondence between the preset speed, the preset torque point and the optimal working point includes: The corresponding relationship between the preset rotation speed, the preset torque point and the optimal working point is stored according to a preset format.

[0011] According to a second aspect of the present disclosure, a motor torque optimization device is provided, comprising: An acquisition unit, used to acquire a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a corresponding relationship between torque and a combination of direct-axis current and quadrature-axis current; A screening unit, configured to screen the coordinate information matrix based on a preset speed point, a preset torque and a preset formula to obtain a combination of the direct-axis current and the quadrature-axis current that satisfies a voltage constraint condition; A confirmation unit, configured to confirm, among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, a direct-axis current and quadrature-axis current combination with a minimum stator current as an optimal operating point based on a maximum torque current ratio control strategy; The iterative calculation unit is used to traverse the preset speed points and the preset torques, iteratively calculate the coordinate information matrix, and obtain the optimal working point under different preset speed points and different preset torques.

[0012] Optionally, the screening unit is further used for: Storing at least one of the preset speed points and at least one of the preset torque points into a preset array; Selecting a target preset speed point and a target torque point in the preset array; Performing torque cycle calculation on the preset torque point based on the target speed point to obtain the direct-axis current and quadrature-axis current combination corresponding to the target preset speed point and the preset torque point; Circularly calculating at least one of the preset speed points and at least one of the preset torque points in the preset array to obtain the direct-axis current and quadrature-axis current combinations corresponding to different preset speed points and different preset torque points; Calculating the stator current synthesis vector and the supply voltage respectively according to different combinations of the direct-axis current and the quadrature-axis current; The stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current are screened based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination that meets the voltage constraint condition.

[0013] Optionally, the iterative calculation unit is further used for: In the non-weakening magnetic field region, confirming that the combination of the direct-axis current and the quadrature-axis current at which the stator current is the minimum value is the optimal operating point; In the weak magnetic field region, the combination of the direct-axis current and the quadrature-axis current corresponding to the stator current that meets the inverter voltage restriction condition and has the highest voltage utilization rate is determined as the optimal operating point.

[0014] Optionally, the acquisition unit further includes: The torque matrix is ​​calculated based on a preset torque formula and motor parameters of the target controlled motor.

[0015] Optionally, the screening unit is further used for: The isotorque line coordinate information of the preset torque point calculated in the current cycle is obtained, and the stator current synthetic vector and the supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the isotorque line coordinate information.

[0016] Optionally, the screening unit is further used for: When it is determined that there is no combination of the direct-axis current and the quadrature-axis current that satisfies the voltage constraint condition, the preset rotation speed and the preset torque point are re-acquired to perform torque cycle calculation.

[0017] Optionally, the iterative calculation unit is further used for: The corresponding relationship between the preset rotation speed, the preset torque point and the optimal working point is stored according to a preset format.

[0018] According to a third aspect of the present disclosure, there is provided an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method described in the first aspect.

[0019] According to a fourth aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to enable the computer to execute the method described in the first aspect.

[0020] According to a fifth aspect of the present disclosure, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements the method as described in the first aspect above.

[0021] The motor torque optimization method, device, electronic device and storage medium provided by the present disclosure have the following main technical solutions: obtaining a pre-configured coordinate information matrix; wherein the coordinate information matrix contains the corresponding relationship between the torque and the combination of the direct-axis current and the quadrature-axis current; screening the coordinate information matrix based on the preset speed point, the preset torque and the preset formula to obtain the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition; in the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition, based on the maximum torque current ratio control strategy, confirming the combination of the direct-axis current and the quadrature-axis current with the minimum stator current as the optimal working point; traversing the preset speed point and the preset torque, iteratively calculating the coordinate information matrix, and obtaining the optimal working point under different preset speed points and different preset torques. Compared with the related art, the embodiment of the present application obtains the equal torque line information by calculation, further calculates and screens the desired optimal point in the equal torque line information, does not need to be calibrated on the test bench for different speed points and torque points, and does not need to be recalibrated on the test bench for multiple voltages, which reduces the workload and time and saves chip resources.

[0022] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure. Figure 1 A classic motor control block diagram provided in an embodiment of the present application; Figure 2 A schematic diagram of a flow chart of a motor torque optimization method provided in an embodiment of the present application; Figure 3 A schematic diagram of equal torque line information provided in an embodiment of the present application; Figure 4 A schematic diagram of a flow chart of another motor torque optimization method provided in an embodiment of the present application; Figure 5 A schematic diagram of a motor torque optimization method provided in an embodiment of the present application; Figure 6 A three-dimensional surface diagram of the d-axis flux parameters of a motor provided by an embodiment of the present disclosure; Figure 7A three-dimensional surface diagram of the q-axis flux parameter of a motor provided by an embodiment of the present disclosure; Figure 8 An Id three-dimensional surface graph provided by an embodiment of the present disclosure; Fig. 9 A three-dimensional surface graph of Iq provided by an embodiment of the present disclosure; Fig.10 An overall display diagram of a dq coordinate system plane provided by an embodiment of the present disclosure; Fig.11 A schematic diagram of the structure of a motor torque optimization device provided in an embodiment of the present disclosure; Fig.12 A schematic block diagram of an exemplary electronic device provided for an embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0025] See also Figure 1 , Figure 1 A classic motor control block diagram provided in the embodiment of the present application, such as Figure 1 As shown, the conversion rule module converts the torque command Converted into current command / A common conversion method is to look up the table. To obtain the table data, it is generally necessary to traverse the dynamometer for different preset DC side voltages, different preset motor speeds, and different preset torque points. , , and the calibration is performed considering the control strategy of the maximum torque current ratio and the limitation of the inverter voltage. This method is labor-intensive and naturally takes a lot of time, and the accuracy depends on the calibration personnel. The motor torque optimization method, device, electronic device and storage medium of the embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0026] Figure 2 A schematic flow chart of a motor torque optimization method provided in an embodiment of the present application.

[0027] like Figure 2 As shown, the method comprises the following steps: Step 101, obtaining a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a correspondence between torque and a combination of direct-axis current and quadrature-axis current.

[0028] In the control and simulation of permanent magnet synchronous motor (PMSM), the direct axis current must be set first. and direct axis current The calculation range of the direct axis current usually refers to the component of the motor stator current on the direct axis (d axis), which is parallel to the magnetic field direction of the permanent magnet. In the maximum torque current ratio (MTPA) control, The purpose of setting is to optimize the operating efficiency of the motor. Ideally, in order to obtain maximum torque, it is usually desired As small as possible, or even zero at certain operating points, to reduce magnetic resistance losses.

[0029] In some embodiments, the direct axis current The range of calculations depends on the physical limitations of the motor and the required control performance; for example, the maximum current limit of the motor, magnetic saturation effects, and the capabilities of the motor controller all affect The calculation range of .

[0030] In this embodiment, the stator current The limit value is 600A. Considering the balance between result accuracy and calculation time, the current calculation accuracy is set to Delta that meets the requirements.

[0031] The motor parameter matrix usually contains the parameters of the motor under different current conditions, such as inductance, flux, etc., which will change with the change of current. In this embodiment, the direct axis flux parameters that meet the accuracy have been measured in advance. , and crankshaft flux parameters .

[0032] Step 102 , screening the coordinate information matrix based on a preset speed point, a preset torque and a preset formula to obtain the direct-axis current and quadrature-axis current combination that meets the voltage constraint condition.

[0033] In some embodiments, different inverters need to set the voltage utilization k used for calculation according to their own voltage modulation capabilities and control performance. In this embodiment, the voltage utilization k=1 is calculated and set. When setting the voltage constraint condition, the limitation of the inverter voltage needs to be considered. In practical applications, the voltage constraint condition can be set according to the actual situation, and the embodiment of the present application does not limit this.

[0034] Step 103 , among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, confirm that the direct-axis current and quadrature-axis current combination with the minimum stator current is the optimal operating point based on the maximum torque current ratio control strategy.

[0035] The torque point values ​​to be calculated are pre-set and stored in the matrix In the encrypted torque matrix Select the coordinate information of the equal torque line in the motor. The equal torque line refers to all current combinations that produce the same torque value in the motor working space. / In a two-dimensional coordinate system, Usually used as the horizontal axis, As the ordinate, the lines of equal torque are curves on these coordinate planes.

[0036] See also Figure 3 , Figure 3 A schematic diagram of an equal torque line information provided in an embodiment of the present application, traversing the torque matrix , find all points with the same torque value. You can set a torque threshold to determine which torque values ​​are considered "equal". For each equal torque value, extract all corresponding current combination coordinates to obtain a line containing multiple equal torque lines. / Coordinates An array M of coordinate information.

[0037] Step 104 , traverse the preset speed points and the preset torques, iteratively calculate the coordinate information matrix, and obtain the optimal working point under different preset speed points and different preset torques.

[0038] The optimal operating point refers to the motor operating state that can achieve the highest efficiency or meet specific performance requirements under a given preset speed and preset torque point, and find a specific current combination on the equal torque line. / , so that the motor runs at the specified speed and torque.

[0039] In some embodiments, preset speed and torque points are traversed, and for each point, an isotorque line coordinate information array is searched to find the closest isotorque line, and the optimal working point is determined on the isotorque line.

[0040] Each preset speed and preset torque point is matched to its corresponding optimal working point / The corresponding relationship storage between them can be achieved by creating a data structure, such as a dictionary, a list or a database, etc. Specifically, the embodiments of the present application are not limited to this.

[0041] The motor torque optimization method provided by the present disclosure has the following main technical solutions: obtaining a pre-configured coordinate information matrix; wherein the coordinate information matrix contains the corresponding relationship between the torque and the combination of the direct-axis current and the quadrature-axis current; screening the coordinate information matrix based on the preset speed point, the preset torque and the preset formula to obtain the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition; in the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition, based on the maximum torque current ratio control strategy, confirming the combination of the direct-axis current and the quadrature-axis current with the minimum stator current as the optimal working point; traversing the preset speed point and the preset torque, iteratively calculating the coordinate information matrix, and obtaining the optimal working point under different preset speed points and different preset torques. Compared with the related art, the embodiment of the present application obtains the equal torque line information by calculation, further calculates and screens the desired optimal point in the equal torque line information, does not need to be calibrated on the test bench for different speed points and torque points, and does not need to be recalibrated on the test bench for multiple voltages, which reduces the workload and time and saves chip resources.

[0042] In some embodiments, when the optimal operating point is confirmed in step 104, the confirmation can also be performed according to the following steps: in the non-weakening magnetic region, confirming that the combination of the direct-axis current and the quadrature-axis current at which the stator current is the minimum value is the optimal operating point; In the weak magnetic field region, the combination of the direct-axis current and the quadrature-axis current corresponding to the stator current that meets the inverter voltage restriction condition and has the highest voltage utilization rate is determined as the optimal operating point.

[0043] In some embodiments, before executing step 101, the following steps are also included: calculating a torque matrix based on a preset torque formula and motor parameters of a target controlled motor.

[0044] Torque is a key performance indicator of motor output. It is generated by the electromagnetic torque and magnetic resistance torque of the motor and is directly related to the current and motor parameters. , , , Substitute into the three-phase permanent magnet synchronous motor torque formula (1): Formula (1) Calculate the encrypted torque matrix ;in, is the number of pole pairs of the motor, and is specifically determined according to the number of pairs of magnetic poles in the motor.

[0045] See also Figure 4 , Figure 4 A schematic flow chart of another motor torque optimization method provided in an embodiment of the present application includes: Preset the speed points to be calculated according to the actual situation and store them in the matrix In the process, the speed cycle calculation is started, and the number of cycles is the matrix The number of elements, starting from the first preset speed point, all the preset torque points at this speed are calculated before the next speed point is calculated, until The speed cycle ends only when all speed points are calculated.

[0046] Step 201, storing at least one of the preset speed points and at least one of the preset torque points into a preset array.

[0047] Step 202 , selecting a target preset speed point and a target torque point from the preset array.

[0048] Step 203 , performing torque cycle calculation on the preset torque point based on the target speed point to obtain the direct-axis current and quadrature-axis current combination corresponding to the target preset speed point and the preset torque point.

[0049] Step 204 , performing cyclic calculation on at least one of the preset speed points and at least one of the preset torque points in the preset array to obtain the direct-axis current and quadrature-axis current combinations corresponding to different preset speed points and different preset torque points.

[0050] In some embodiments, when executing step 204, calculations can also be performed according to the following steps: obtaining the equal torque line coordinate information of the preset torque point calculated in the current cycle, and calculating the stator current synthetic vector and the supply voltage corresponding to each coordinate point based on all coordinate information in the equal torque line coordinate information.

[0051] Step 205 , respectively calculating the stator current synthesis vector and the supply voltage according to different combinations of the direct-axis current and the quadrature-axis current.

[0052] The stator current synthetic vector and the power supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the equal torque line coordinate information.

[0053] In order to obtain the optimal torque at the speed we expect / Combination, based on the steady-state model of the motor, the corresponding stator current synthesis vector needs to be further calculated according to formula (2)-formula (5) and supply voltage

[0054] Formula (2) Formula (3) Formula (4) Formula (5) In the formula is the measured motor stator phase resistance, , , for this group / , combined with the motor d / q axis flux obtained from the table, is the current calculated speed; select the equal torque line coordinate information corresponding to the current torque cycle step from the preset array, that is, all corresponding / .combination.

[0055] Step 206 , based on the voltage constraint condition, the stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current are screened to obtain the direct-axis current and the quadrature-axis current combination that satisfies the voltage constraint condition.

[0056] The isotorque line coordinate information of the preset torque point calculated in the current cycle is obtained, and the stator current synthetic vector and the supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the isotorque line coordinate information.

[0057] In this embodiment, the DC voltage Set to 750V, the voltage utilization of the two-level inverter is defined by formula (6): Formula (6), (0 <k<1.1) Different inverters need to set the voltage utilization factor k used for calculation according to their own voltage modulation capability and control performance.

[0058] In this embodiment, the voltage utilization rate k is calculated to be 1. Considering the limitation of the inverter voltage, the calculation results are Should be less than or equal to According to this condition, the elements that meet the requirements are selected and stored in the constTorqueLine matrix, and the corresponding array subscripts are stored in the matrix UsLimResIndex.

[0059] The supply voltage corresponding to the target stator current synthesis vector is determined as the optimal operating point.

[0060] Considering the maximum torque current ratio control strategy, the calculated The elements in the matrix whose subscript is the matrix UsLimResIndex element are filtered and recorded The minimum subscript is MinlsIndex. In the non-weakening magnetic region, this point is the MTPA operating point. In the weakening magnetic region, this point is the current that satisfies the inverter voltage limit condition and has the highest voltage utilization rate at this speed and torque. The minimum expected optimal operating point.

[0061] Reversely map Minlsindex to the matrix ConstTorqueline obtained by S5 to save the optimal operating point result of this speed torque point =ConstTorqueLine(1,UsLimResIndex(MinlsIndex)), The second row of the corresponding column.

[0062] When it is determined that there is no combination of the direct-axis current and the quadrature-axis current that satisfies the voltage constraint condition, the preset rotation speed and the preset torque point are re-acquired to perform torque cycle calculation.

[0063] Determine whether the matrix UsLimResIndex is empty. If it is an empty matrix, it means that all points on the equal torque line All are higher than the inverter voltage limit, the voltage limit ellipse has no intersection with the equal torque line, and the motor cannot output this torque at this speed. The torque calculation at this speed is completed, and the calculation of the next preset speed point is returned to S3. Otherwise, it indicates that there are torque points on the equal torque line that meet the inverter voltage limit. At this time, it is necessary to enter the next state to further screen these torque points.

[0064] In some embodiments, storing the corresponding relationship between the preset speed, the preset torque point and the optimal working point includes: The corresponding relationship between the preset rotation speed, the preset torque point and the optimal working point is stored according to a preset format.

[0065] The above simulation calculation results are stored in the required format, and the matrix format is used for software table lookup.

[0066] See also Figure 5 , Figure 5 A schematic diagram of a motor torque optimization method provided in an embodiment of the present application is shown below. The implementation scheme of the present invention is described in detail in conjunction with the flow chart. The D-axis flux parameters of the high-precision motor to be measured are prepared. ,Q-axis flux parameters and , according to the torque calculation formula, the motor torque is obtained Then draw the torque contour line and save the return value to obtain the coordinate information array M of the equal torque line of all torque points. M contains all the target torque curve clusters defined previously. Coordinate value.

[0067] Use a loop structure to traverse the speed and torque points to be calculated, extract the coordinate information of the corresponding equal torque line in the coordinate information array M and define it into a new array ConstTorqueLine, and then calculate the corresponding , , considering the maximum torque current ratio control strategy and the inverter voltage limit, the expected optimal working point is selected, and the obtained results are organized into the matrix form required in the software for software table lookup. The present invention can save the calibration process of each speed point and torque point under different voltages on the dynamometer bench, and the simulation calculation time takes less than one minute, which greatly reduces the workload, saves time and resources. In addition, due to the high calculation accuracy and no introduction of human factors, the quality and consistency of the results are improved, so that the motor can run at the expected optimal working point under different speeds and voltage conditions. In addition, it can easily adapt to changes in DC voltage without using multiple voltage tables, saving storage space and reducing additional table lookup operations.

[0068] Based on the actual measured difference / Motor DQ axis flux parameter matrix under combination , , the corresponding torque matrix can be calculated, and then the contour lines of all preset torque points can be drawn and their coordinate information can be returned. Each contour line is composed of several groups of / , the coordinate combination represents the equal torque points. We can further calculate the current and voltage of each point, and select the control strategy that considers the maximum torque current ratio and the inverter voltage limitation. / The combined point is the expected optimal working point.

[0069] In order to facilitate understanding of the motor torque optimization method provided in the embodiment of the present application, an example is used below to illustrate.

[0070] Please continue reading Figure 3 , when the torque point is known / After the combination, the optimal / combination.

[0071] Based on the actual measured difference / Motor DQ axis flux parameter matrix under combination / , / ,like Figure 6 and Figure 7 As shown, Figure 6A three-dimensional surface diagram of the d-axis flux parameters of a motor provided in an embodiment of the present application; Figure 7 A three-dimensional surface diagram of the q-axis magnetic flux parameter matrix of a motor provided in an embodiment of the present application; the corresponding torque matrix can be obtained by calculation, and then the contour lines of all preset torque points are drawn and their coordinate information is returned at the same time. Each contour line is composed of several groups of equal torque points represented by 𝐼d / 𝐼q coordinate combinations. Further, we can calculate the current and voltage of each point, and screen out the points of the 𝐼d / 𝐼q combination that considers the control strategy of the maximum torque-to-current ratio and the limitation of the inverter voltage, which is the desired optimal operating point.

[0072] S1: stator current in this embodiment The limit value of , is 600A. Considering the balance between result accuracy and calculation time, the current calculation accuracy is set to Delta. According to the measured motor parameters and the three-phase permanent magnet synchronous motor torque formula (1), the torque matrix is ​​calculated .

[0073] Formula (1) S2: Preset the torque point values ​​to be calculated and store them in the matrix Then draw the contour lines of these torque points in the dq coordinate system plane and save the return values ​​in the matrix M, which contains the torque and / Coordinate information.

[0074] S3: Preset the speed points to be calculated according to the actual situation and store them in the matrix In the process, the speed cycle calculation is started, and the number of cycles is the matrix The number of elements, starting from the first preset speed point, all the preset torque points at this speed are calculated before the next speed point is calculated, until The speed cycle ends only when all speed points are calculated.

[0075] S4: Start torque cycle calculation at the speed point preset in the current speed cycle step in S3, and the number of cycles is the matrix The number of elements from The torque loop starts from the first element in and ends when all torque points are calculated.

[0076] S5: Select the coordinate information of the equal torque line corresponding to the current torque cycle step in S4 from the matrix M, that is, all corresponding / Put the combination in the matrix constTorqueLine, so that all points of the preset torque equal torque line are obtained / In order to obtain the optimal torque at the desired speed / Combination, based on the steady-state model of the motor, needs to be further calculated according to formula (2)-formula (5) and

[0077] Formula (2) Formula (3) Formula (4) Formula (5) In the formula is the measured motor stator phase resistance, , , for this group / , combined with the motor d / q axis flux obtained from the table, Calculate the current speed S6: The DC voltage used in this embodiment is 750V, and the voltage utilization of the two-level inverter is defined by formula (5): Formula (5), (0 <k<1.1) Different inverters need to set the voltage utilization factor k used for calculation according to their own voltage modulation capability and control performance.

[0078] In this embodiment, the voltage utilization rate k is calculated to be 1. Considering the limitation of the inverter voltage, the voltage utilization rate of all points is calculated in S7. Should be less than or equal to According to this condition, the elements that meet the requirements are selected and stored in the constTorqueLine matrix, and the corresponding array subscripts are stored in the matrix UsLimResIndex.

[0079] S7: Determine whether the matrix UsLimResIndex is empty. If it is an empty matrix, it means that all points on the equal torque line All are higher than the inverter voltage limit, the voltage limit ellipse has no intersection with the equal torque line, and the motor cannot output this torque at this speed. The torque calculation at this speed is completed, and the calculation of the next preset speed point is returned to S3. Otherwise, it indicates that there are torque points on the equal torque line that meet the inverter voltage limit. At this time, it is necessary to enter the next state to further screen these torque points.

[0080] S8: Consider the maximum torque current ratio control strategy and convert the value calculated in S5 The elements in the matrix whose subscript is the matrix UsLimResIndex element are filtered and recorded The minimum subscript is MinlsIndex. In the non-weakening magnetic region, this point is the MTPA operating point. In the weakening magnetic region, this point is the current that satisfies the inverter voltage limit condition and has the highest voltage utilization rate at this speed and torque. The minimum expected optimal operating point.

[0081] S9: Reversely map the Minlsindex obtained in S10 to the matrix ConstTorqueline obtained in S5, and save the optimal operating point result of this speed torque point =ConstTorqueLine(1,UsLimResIndex(MinlsIndex)), The second row of the corresponding column.

[0082] S10: Store the above simulation calculation results in the required format, where the matrix format is used for software table lookup and the column vector format is used for archiving. Figure 8 and Fig. 9 , Figure 8 An Id three-dimensional surface graph provided in an embodiment of the present application; Fig. 9 This is a three-dimensional Iq surface diagram provided by the embodiment of the present application, wherein the column vector format is used for archiving. After a finite number of cycles of calculation, the entire simulation calculation results of all preset speeds and torque points are displayed as a whole on the dq coordinate plane as follows Fig.10 As shown, Fig.10 An overall display diagram of a coordinate system plane provided in an embodiment of the present application.

[0083] The motor control block diagram according to the embodiment of the present invention obtains / The matrix is ​​substituted into the software table. The input of the table is the motor speed and the target torque. The measured torque can make the motor output and the target torque match. The torque accuracy in the full speed torque range can reach the standard of torque error within 100Nm within 2Nm and torque error within 2% above 100Nm. In addition, the voltage in the weak magnetic area under steady-state operation is The average value can always satisfy the voltage utilization rate of 1. The actual operation results of the embodiment of the present invention confirm the effectiveness and accuracy of this calculation method.

[0084] It can be found that this method does not need to be calibrated on the test bench for different speed points and torque points, nor does it need to be recalibrated on the test bench for multiple voltages. In addition, the software does not need table lookup data and calculations for multiple voltages to adapt to DC voltage changes. The entire simulation calculation process takes less than 1 minute to get the required results, greatly reducing the workload and time, saving chip resources, and at the same time can accurately run at the expected optimal operating point considering the maximum torque-to-current ratio control strategy and voltage utilization factors.

[0085] Corresponding to the above motor torque optimization method, the present invention also provides a motor torque optimization device. Since the device embodiment of the present invention corresponds to the above method embodiment, details not disclosed in the device embodiment can be referred to the above method embodiment, and will not be repeated in the present invention.

[0086] Fig.11 A schematic diagram of the structure of a motor torque optimization device provided by an embodiment of the present disclosure, such as Fig.11 As shown, including: An acquisition unit 31 is used to acquire a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a corresponding relationship between torque and a combination of a direct-axis current and a quadrature-axis current; A screening unit 32, configured to screen the coordinate information matrix based on a preset speed point, a preset torque and a preset formula to obtain a combination of the direct-axis current and the quadrature-axis current that satisfies a voltage constraint condition; A confirmation unit 33 is used to confirm, among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal operating point based on the maximum torque current ratio control strategy; The iterative calculation unit 34 is used to traverse the preset speed points and the preset torques, iteratively calculate the coordinate information matrix, and obtain the optimal working point under different preset speed points and different preset torques.

[0087] The motor torque optimization device provided by the present disclosure has a main technical solution including: obtaining a pre-configured coordinate information matrix; wherein the coordinate information matrix contains the corresponding relationship between the torque and the combination of the direct-axis current and the quadrature-axis current; screening the coordinate information matrix based on the preset speed point, the preset torque and the preset formula to obtain the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition; in the combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition, based on the maximum torque current ratio control strategy, confirming the combination of the direct-axis current and the quadrature-axis current with the minimum stator current as the optimal working point; traversing the preset speed point and the preset torque, iteratively calculating the coordinate information matrix, and obtaining the optimal working point under different preset speed points and different preset torques. Compared with the related art, the embodiment of the present application obtains the equal torque line information by calculation, and further calculates and screens the desired optimal point in the equal torque line information, and does not need to be calibrated on the test bench for different speed points and torque points, nor does it need to be recalibrated on the test bench for multiple voltages, which reduces the workload and time and saves chip resources.

[0088] Furthermore, in a possible implementation of the embodiment of the present disclosure, the screening unit 32 is further configured to: Storing at least one of the preset speed points and at least one of the preset torque points into a preset array; Selecting a target preset speed point and a target torque point in the preset array; Performing torque cycle calculation on the preset torque point based on the target speed point to obtain the direct-axis current and quadrature-axis current combination corresponding to the target preset speed point and the preset torque point; Circularly calculating at least one of the preset speed points and at least one of the preset torque points in the preset array to obtain the direct-axis current and quadrature-axis current combinations corresponding to different preset speed points and different preset torque points; Calculating the stator current synthesis vector and the supply voltage respectively according to different combinations of the direct-axis current and the quadrature-axis current; The stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current are screened based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination that meets the voltage constraint condition.

[0089] Furthermore, in a possible implementation of the embodiment of the present disclosure, the iterative calculation unit 34 is further configured to: In the non-weakening magnetic field region, confirming that the combination of the direct-axis current and the quadrature-axis current at which the stator current is the minimum value is the optimal operating point; In the weak magnetic field region, the combination of the direct-axis current and the quadrature-axis current corresponding to the stator current that meets the inverter voltage restriction condition and has the highest voltage utilization rate is determined as the optimal operating point.

[0090] Furthermore, in a possible implementation of the embodiment of the present disclosure, the acquisition unit 31 further includes: The torque matrix is ​​calculated based on a preset torque formula and motor parameters of the target controlled motor.

[0091] Furthermore, in a possible implementation of the embodiment of the present disclosure, the screening unit 32 is further configured to: The isotorque line coordinate information of the preset torque point calculated in the current cycle is obtained, and the stator current synthetic vector and the supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the isotorque line coordinate information.

[0092] Furthermore, in a possible implementation of the embodiment of the present disclosure, the screening unit 32 is further configured to: When it is determined that there is no combination of the direct-axis current and the quadrature-axis current that satisfies the voltage constraint condition, the preset rotation speed and the preset torque point are re-acquired to perform torque cycle calculation.

[0093] Furthermore, in a possible implementation of the embodiment of the present disclosure, the iterative calculation unit 34 is further configured to: The corresponding relationship between the preset rotation speed, the preset torque point and the optimal working point is stored according to a preset format.

[0094] It should be noted that the above explanation of the method embodiment is also applicable to the device of the embodiment of the present disclosure, and the principle is the same, which is no longer limited in the embodiment of the present disclosure.

[0095] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device, a readable storage medium and a computer program product.

[0096] Fig.12 A schematic block diagram of an example electronic device 400 that can be used to implement an embodiment of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present disclosure described and / or required herein.

[0097] like Fig.12As shown, the device 400 includes a computing unit 401, which can perform various appropriate actions and processes according to a computer program stored in a ROM (Read-Only Memory) 402 or a computer program loaded from a storage unit 408 to a RAM (Random Access Memory) 403. Various programs and data required for the operation of the device 400 can also be stored in the RAM 403. The computing unit 401, the ROM 402, and the RAM 403 are connected to each other via a bus 404. An I / O (Input / Output) interface 405 is also connected to the bus 404.

[0098] A number of components in the device 400 are connected to the I / O interface 405, including: an input unit 406, such as a keyboard, a mouse, etc.; an output unit 407, such as various types of displays, speakers, etc.; a storage unit 408, such as a disk, an optical disk, etc.; and a communication unit 409, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 409 allows the device 400 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0099] The computing unit 401 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 401 include, but are not limited to, a CPU (Central Processing Unit), a GPU (Graphic Processing Units), various dedicated AI (Artificial Intelligence) computing chips, various computing units running machine learning model algorithms, a DSP (Digital Signal Processor), and any appropriate processor, controller, microcontroller, etc. The computing unit 401 performs the various methods and processes described above, such as the motor torque optimization method. For example, in some embodiments, the motor torque optimization method may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 408. In some embodiments, part or all of the computer program may be loaded and / or installed on the device 400 via the ROM 402 and / or the communication unit 409. When the computer program is loaded into the RAM 403 and executed by the computing unit 401, one or more steps of the method described above may be performed. Alternatively, in other embodiments, the computing unit 401 may be configured to execute the aforementioned motor torque optimization method in any other appropriate manner (for example, by means of firmware).

[0100] Various embodiments of the systems and techniques described above herein may be implemented in digital electronic circuit systems, integrated circuit systems, FPGAs (Field Programmable Gate Arrays), ASICs (Application-Specific Integrated Circuits), ASSPs (Application Specific Standard Products), SOCs (System On Chips), CPLDs (Complex Programmable Logic Devices), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include: being implemented in one or more computer programs that may be executed and / or interpreted on a programmable system including at least one programmable processor that may be a dedicated or general-purpose programmable processor that may receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0101] The program code for implementing the method of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0102] In the context of the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or apparatus. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any suitable combination of the foregoing. More specific examples of machine-readable storage media may include an electrical connection based on one or more wires, a portable computer disk, a hard disk, RAM, ROM, EPROM (Electrically Programmable Read-Only-Memory) or flash memory, optical fiber, CD-ROM (Compact Disc Read-Only Memory), optical storage device, magnetic storage device, or any suitable combination of the foregoing.

[0103] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (Cathode-Ray Tube) or LCD (Liquid Crystal Display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0104] The systems and techniques described herein may be implemented in a computing system that includes a backend component (e.g., as a data server), or a computing system that includes a middleware component (e.g., an application server), or a computing system that includes a frontend component (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: LAN (Local Area Network), WAN (Wide Area Network), the Internet, and blockchain networks.

[0105] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship between the client and the server is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services ("Virtual Private Server", or "VPS" for short). The server may also be a server of a distributed system, or a server combined with a blockchain.

[0106] It should be noted that artificial intelligence is a discipline that studies how computers can simulate certain human thought processes and intelligent behaviors (such as learning, reasoning, thinking, planning, etc.), and includes both hardware-level and software-level technologies. Artificial intelligence hardware technologies generally include technologies such as sensors, dedicated artificial intelligence chips, cloud computing, distributed storage, and big data processing; artificial intelligence software technologies mainly include computer vision technology, speech recognition technology, natural language processing technology, as well as machine learning / deep learning, big data processing technology, knowledge graph technology, and other major directions.

[0107] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0108] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A motor torque optimization method, characterized in that: include: Acquire a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a corresponding relationship between torque and a combination of direct-axis current and quadrature-axis current; The coordinate information matrix is ​​screened based on a preset speed point, a preset torque and a preset formula to obtain a combination of the direct-axis current and the quadrature-axis current that meets the voltage constraint condition; In the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, based on the maximum torque current ratio control strategy, confirming the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal operating point; The preset speed points and the preset torques are traversed, and the coordinate information matrix is ​​iteratively calculated to obtain the optimal working point under different preset speed points and different preset torques.

2. The motor torque optimization method according to claim 1, characterized in that: The coordinate information matrix is ​​screened based on the preset speed point, the preset torque and the preset formula to obtain the direct-axis current and quadrature-axis current combination that meets the voltage constraint condition, including: Storing at least one of the preset speed points and at least one of the preset torque points into a preset array; Selecting a target preset speed point and a target torque point in the preset array; Performing torque cycle calculation on the preset torque point based on the target speed point to obtain the direct-axis current and quadrature-axis current combination corresponding to the target preset speed point and the preset torque point; Circularly calculating at least one of the preset speed points and at least one of the preset torque points in the preset array to obtain the direct-axis current and quadrature-axis current combinations corresponding to different preset speed points and different preset torque points; Calculating the stator current synthesis vector and the supply voltage respectively according to different combinations of the direct-axis current and the quadrature-axis current; The stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current are screened based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination that meets the voltage constraint condition.

3. The motor torque optimization method according to claim 1, characterized in that: The step of confirming, among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, the direct-axis current and quadrature-axis current combination with the minimum stator current as the optimal operating point based on the maximum torque current ratio control strategy comprises: In the non-weakening magnetic field region, confirming that the combination of the direct-axis current and the quadrature-axis current at which the stator current is the minimum value is the optimal operating point; In the weak magnetic field region, the combination of the direct-axis current and the quadrature-axis current corresponding to the stator current that meets the inverter voltage restriction condition and has the highest voltage utilization rate is determined as the optimal operating point.

4. The motor torque optimization method according to claim 1, characterized in that: Before obtaining the pre-configured coordinate information matrix, the method further includes: The torque matrix is ​​calculated based on a preset torque formula and motor parameters of the target controlled motor.

5. The motor torque optimization method according to claim 2, characterized in that: The performing torque cycle calculation on the preset torque point based on the target speed point comprises: The isotorque line coordinate information of the preset torque point calculated in the current cycle is obtained, and the stator current synthetic vector and the supply voltage corresponding to each coordinate point are calculated according to all coordinate information in the isotorque line coordinate information.

6. The motor torque optimization method according to claim 2, characterized in that: The step of screening the stator current synthetic vector and the supply voltage corresponding to different combinations of the direct-axis current and the quadrature-axis current based on the voltage constraint condition to obtain the direct-axis current and the quadrature-axis current combination that satisfies the voltage constraint condition further includes: When it is determined that there is no combination of the direct-axis current and the quadrature-axis current that satisfies the voltage constraint condition, the preset rotation speed and the preset torque point are re-acquired to perform torque cycle calculation.

7. The motor torque optimization method according to any one of claims 1 to 6, characterized in that: After obtaining the optimal working points under different preset speed points and different preset torques, the method further includes: The corresponding relationship between the preset rotation speed, the preset torque point and the optimal working point is stored according to a preset format.

8. A motor torque optimization device, characterized in that: include: An acquisition unit, used to acquire a pre-configured coordinate information matrix; wherein the coordinate information matrix includes a corresponding relationship between torque and a combination of direct-axis current and quadrature-axis current; A screening unit, configured to screen the coordinate information matrix based on a preset speed point, a preset torque and a preset formula to obtain a combination of the direct-axis current and the quadrature-axis current that satisfies a voltage constraint condition; A confirmation unit, configured to confirm, among the direct-axis current and quadrature-axis current combinations satisfying the voltage constraint condition, a direct-axis current and quadrature-axis current combination with a minimum stator current as an optimal operating point based on a maximum torque current ratio control strategy; The iterative calculation unit is used to traverse the preset speed points and the preset torques, iteratively calculate the coordinate information matrix, and obtain the optimal working point under different preset speed points and different preset torques.

9. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium storing computer instructions, characterized in that: The computer instructions are used to cause the computer to execute the method according to any one of claims 1-7.

11. A computer program product, characterized in that The invention comprises a computer program which, when executed by a processor, implements the method according to any one of claims 1 to 7.

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