Motor system control method and device, electronic equipment and storage medium

Abstract

The invention relates to the technical field of vehicles, and discloses a control method and device of a motor system, electronic equipment and a storage medium, and the control method comprises the steps: determining a current direct-axis current, a current direct-axis inductance, a current quadrature-axis current and a current quadrature-axis inductance according to a current torque and a current rotating speed of the motor system; according to the current rotating speed, the current direct-axis current, the current direct-axis inductance, the current quadrature-axis current, the current quadrature-axis inductance and the motor flux linkage, a current back electromotive force value is obtained through calculation; calculating to obtain a to-be-selected switching frequency according to the current back electromotive force value, the rated voltage of the power battery, the equivalent inductance of the motor system and the maximum preset ripple current; if the limited switching frequency exists, the current switching frequency is determined according to the magnitude relation between the to-be-selected switching frequency and the maximum limited switching frequency, and the motor system is controlled to operate based on the current switching frequency. The squeal suppression effect is ensured, and meanwhile, the switching loss is considered.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, specifically to a control method, device, electronic equipment, and storage medium for an electric motor system. Background Technology

[0002] The current output by the inverter in the motor system is not an ideal sine wave. It contains high-frequency components caused by the switching frequency and its sideband ripple. At the same time, the current ripple generates a high-frequency magnetic field in the air gap, which interacts with the permanent magnet or rotor magnetic field to generate an alternating radial electromagnetic force, which may cause resonance and cause howling.

[0003] Some related technologies for improving motor system whistling focus on the hardware level, requiring complex hardware design. The whistling suppression effect depends on the success of the hardware design and is difficult to verify in the initial design stage. Other related technologies focus on the software level, using harmonic injection strategies or random frequency conversion strategies. Although they can suppress motor system whistling to some extent, the suppression effect is poor or excessive, exacerbating switching losses. Summary of the Invention

[0004] In view of the above problems, this application provides a control method, device, electronic device and computer-readable storage medium for a motor system, which is used to select a switching frequency suitable for the current scenario and control the operation of the motor system to ensure the squealing suppression effect while taking into account the switching losses.

[0005] According to one aspect of this application, a control method for a motor system is provided. The control method includes: determining the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system; calculating the current back electromotive force (EMF) value based on the current speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage; calculating a candidate switching frequency based on the current back EMF value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current; and if a limiting switching frequency exists, determining the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency, and controlling the operation of the motor system based on the current switching frequency.

[0006] In one optional approach, determining the current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage based on the current torque and current speed of the motor system includes: determining the target preset torque range to which the current torque of the motor system belongs, and the target preset speed range to which the current speed belongs; and determining a target preset operating condition parameter set based on the target preset torque range and the target preset speed range to determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance.

[0007] In one optional approach, calculating the current back electromotive force (EMF) value based on the current rotational speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage includes: squaring the product of the current quadrature-axis current and the current quadrature-axis inductance to obtain a first squared value; summing the product of the current direct-axis current and the current direct-axis inductance with the motor flux linkage, and squaring the sum to obtain a second squared value; and performing a root operation on the sum of the first squared value and the second squared value, and multiplying the root value with the current rotational speed to obtain the current back EMF value.

[0008] In one optional approach, calculating the candidate switching frequency based on the current back EMF value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current includes: subtracting the rated voltage of the power battery from the current back EMF value to obtain a difference; multiplying the equivalent inductance of the motor system, the maximum preset ripple current, and a preset coefficient to obtain a product; wherein the preset coefficient corresponds to a preset duty cycle; and dividing the difference by the product to obtain the candidate switching frequency.

[0009] In one optional approach, determining the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency includes: if the candidate switching frequency is greater than or equal to the maximum limiting switching frequency, then the maximum limiting switching frequency is determined as the current switching frequency; if the candidate switching frequency is less than the maximum limiting switching frequency, then the candidate switching frequency is determined as the current switching frequency.

[0010] In one alternative approach, the control method further includes: determining the current torque of the motor system based on the current original torque request value; wherein the current original torque request value is derived from the vehicle controller; calibrating the original resolver signal; and determining the current rotational speed based on the calibrated original resolver signal.

[0011] In an optional embodiment, the control method further includes: if there is no limiting switching frequency, then using the candidate switching frequency as the current switching frequency, and controlling the operation of the motor system based on the current switching frequency.

[0012] According to another aspect of this application, a control device for a motor system is provided. The control device includes: a determining module, configured to determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system; a first calculation module, configured to calculate the current back electromotive force (EMF) value based on the current speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage; a second calculation module, configured to calculate the candidate switching frequency based on the current back EMF value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current; and a control module, configured to determine the current switching frequency based on the relationship between the candidate switching frequency and the maximum limited switching frequency if a limiting switching frequency exists, and control the operation of the motor system based on the current switching frequency.

[0013] According to one aspect of this application, an electronic device is provided, comprising: a controller; and a memory for storing one or more programs, which, when executed by the controller, perform the control method described above.

[0014] According to one aspect of this application, a computer-readable storage medium is also provided, on which computer-readable instructions are stored, which, when executed by a computer's processor, cause the computer to perform the control method described above.

[0015] According to one aspect of this application, a computer program product or computer program is also provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the control method described above.

[0016] Based on the real-time torque and real-time speed of the motor system, this application determines the relevant real-time operating parameters of the motor system, and calculates the candidate switching frequency with the best whistling suppression effect by combining the real-time parameters of the power battery and other inherent parameters. In the case of a limited switching frequency, the real-time switching frequency used to control the operation of the motor system is determined according to the relationship between the candidate switching frequency and the maximum limited switching frequency, so as to ensure the whistling suppression effect while taking into account the switching losses.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] Figure 1 This is a flowchart illustrating a control method for a motor system according to an exemplary embodiment of this application.

[0020] Figure 2 is based on Figure 1 The exemplary embodiment shown illustrates a flowchart of another control method for a motor system.

[0021] Figure 3 This is a schematic diagram illustrating the application scenario of the control method for the motor system of this application.

[0022] Figure 4 This is a flowchart illustrating the server execution logic in an exemplary embodiment of this application.

[0023] Figure 5 This is a schematic diagram of the structure of a control device for a motor system shown in an exemplary embodiment of this application.

[0024] Figure 6 This is a schematic diagram of the structure of a computer system for an electronic device illustrated in an exemplary embodiment of this application. Detailed Implementation

[0025] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0026] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0027] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0028] In this application, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0029] Some related technologies for improving motor system whistling focus on the hardware level, requiring complex hardware design. The whistling suppression effect depends on the success of the hardware design and is difficult to verify in the initial design stage. Other related technologies focus on the software level, using harmonic injection strategies or random frequency conversion strategies. Although they can suppress motor system whistling to some extent, the suppression effect is poor or excessive, exacerbating switching losses.

[0030] This application does not improve the hardware of the motor system. The applicant discovered that appropriately increasing the switching frequency of the motor system can reduce the current ripple, thereby reducing the electromagnetic excitation force and significantly improving the whistling sound perceptible to the human ear. However, prolonged high-frequency switching leads to increased switching losses, resulting in reduced electronic control efficiency. At the same time, the increased heat generation also increases the risk of damage to the IGBT (Insulated Gate Bipolar Transistor).

[0031] Therefore, one aspect of this application provides a control method for a motor system. Based on relevant parameters of the motor system and the power battery, the optimal switching frequency for suppressing whistling in the current scenario is calculated. Further, by combining this with a limiting switching frequency, a suitable switching frequency for the current scenario is determined, and the motor system is controlled to operate, thus ensuring whistling suppression while also considering switching losses. Please refer to [link / reference] for details. Figure 1 , Figure 1This is a schematic flowchart illustrating a control method for a motor system according to an exemplary embodiment of this application. The control method includes at least steps S110 to S140, which are described in detail below:

[0032] S110: Determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system.

[0033] Based on the real-time torque and actual speed of the motor system, the relevant real-time operating parameters of the motor system can be quickly determined, including but not limited to the current and inductance of the d-axis (direct axis) and q-axis (quadrature axis).

[0034] For example, the target preset torque range to which the current torque of the motor system belongs and the target preset speed range to which the current speed belongs are determined respectively; based on the target preset torque range and the target preset speed range, the target preset operating condition parameter set is determined to determine the current direct axis current, the current direct axis inductance, the current quadrature axis current and the current quadrature axis inductance.

[0035] Based on the magnitude of the torque, three preset torque ranges are obtained by dividing the torque range into three critical torque values: the preset low torque range (between zero and the first critical torque value), the preset medium torque range (between the first and second critical torque values), and the preset high torque range (between the second and third critical torque values).

[0036] Based on the speed, four preset speed ranges are obtained using four critical speed values: preset stall range (between zero and the first critical speed value), preset low speed range (between the first and second critical speed values), preset medium speed range (between the second and third critical speed values), and preset high speed range (between the third and fourth critical speed values).

[0037] The experimental data from calibration experiments can establish a mapping relationship between torque, speed, and relevant operating condition parameters, thereby constructing a preset relationship table between the corresponding preset torque range, preset speed range, and relevant operating condition parameters. As shown in Table 1, Table 1 is a set of preset torque, preset speed, and preset operating condition parameter relationships. The current torque and current speed are used as two positioning parameters to determine the corresponding target preset ranges, thereby determining the target preset speed range and target preset torque range, and subsequently determining the target preset operating condition parameter set, thus determining the corresponding direct-axis current, direct-axis inductance, quadrature-axis current, and quadrature-axis inductance. Each preset operating condition parameter set in Table 1 includes corresponding preset parameters such as preset direct-axis current, preset direct-axis inductance, preset quadrature-axis current, and preset quadrature-axis inductance. Different preset operating condition parameter sets may be the same (all parameters in the corresponding set are identical), or they may be different, or some of their preset parameters may be the same; this application does not limit this.

[0038] Table 1: Relationship between preset torque, preset speed, and preset operating condition parameters

[0039]

[0040]

[0041] S120: Calculate the current back electromotive force value based on the current speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage.

[0042] For example, the product of the current quadrature-axis current and the current quadrature-axis inductance is squared to obtain a first squared value; the product of the current direct-axis current and the current direct-axis inductance is summed with the motor flux linkage, and the sum is squared to obtain a second squared value; the sum of the first and second squared values ​​is rooted, and the root is multiplied by the current rotational speed to obtain the current back electromotive force (EMF) value. The calculation formula is as follows:

[0043] Among them, V e W represents the back electromotive force. e L represents rotational speed (in radians). q I represents quadrature axis inductance. q L represents the quadrature-axis current. d I represents direct-axis inductance. d Ψ represents the direct-axis current and the motor flux linkage.

[0044] S130: The candidate switching frequency is calculated based on the current back EMF value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current.

[0045] For example, the difference between the rated voltage of the power battery and the current back electromotive force is calculated to obtain the difference; the equivalent inductance of the motor system, the maximum preset ripple current, and the preset coefficient are multiplied to obtain the product; wherein the preset coefficient corresponds to the preset duty cycle; the difference is divided by the product to obtain the selectable switching frequency.

[0046] Among them, f s Indicates the selectable switching frequency, V dc The rated voltage of the power battery is represented by L, the equivalent inductance is represented by ΔI. max Indicates the maximum preset ripple current. V represents the preset coefficient. e W represents the back electromotive force. e L represents rotational speed (in radians). q I represents quadrature axis inductance. q L represents the quadrature-axis current. d I represents direct-axis inductance. d Let f represent the direct-axis current and Ψ represent the motor flux linkage. From this formula, it can be seen that if the speed or torque increases, the calculated f... s Reducing the frequency can suppress the whistling sound, but considering the risk of overheating damage, the switching frequency should be limited according to the power module's limit capacity.

[0047] Below is ΔI max The determination process is explained as follows: In a motor system, the magnitude of the current ripple is mainly related to the voltage step, winding inductance, and switching frequency. Within a single switching cycle, the expression for the current ripple can be approximated as follows: Where D represents the duty cycle, if D is 0.5, the voltage utilization rate of SVPWM (Space Vector Pulse Width Modulation) modulation is higher than that of traditional modulation methods. The current ripple is relatively smaller, and at this point, the ripple ΔI has a maximum value, which is the maximum allowable ripple limit of the system.

[0048] S140: If there is a limiting switching frequency, the current switching frequency is determined according to the relationship between the candidate switching frequency and the maximum limiting switching frequency, and the motor system is controlled to operate based on the current switching frequency.

[0049] The limiting switching frequency is a frequency range used to prevent overheating and damage to the switch. The limiting switching frequency includes a minimum limiting switching frequency and a maximum limiting switching frequency. Exceeding the limiting switching frequency cannot guarantee stable switch operation. To achieve both howling suppression and consideration of switching losses, this embodiment compares the maximum limiting switching frequency with the real-time calculated candidate switching frequency to determine the current switching frequency that balances both requirements, and controls the motor system operation based on the current switching frequency.

[0050] For example, if the selected switching frequency is greater than or equal to the maximum limiting switching frequency, the maximum limiting switching frequency is determined as the current switching frequency; if the selected switching frequency is less than the maximum limiting switching frequency, the selected switching frequency is determined as the current switching frequency.

[0051] If the selected switching frequency is greater than or equal to the maximum limiting switching frequency, it indicates that the selected switching frequency exceeds the limit and may cause overheating and losses in the switch. In this case, the maximum limiting switching frequency is determined as the current switching frequency to maximize the squeal suppression requirement while ensuring the stability of the switch. If the selected switching frequency is less than the maximum limiting switching frequency, it indicates that the switching frequency with the best squeal suppression effect will not cause overheating and losses in the switch. In this case, the selected switching frequency is determined as the current switching frequency to achieve the best squeal suppression effect.

[0052] If there is no limitation on the switching frequency, the candidate switching frequency is used as the current switching frequency, and the motor system operation is controlled based on the current switching frequency. If there is no limitation on the switching frequency, it means that there is no need to consider switching losses, and the goal is directly to suppress whistling, so the candidate switching frequency is used as the current switching frequency.

[0053] This embodiment determines the relevant real-time operating parameters of the motor system based on the real-time torque and real-time speed of the motor system, and calculates the candidate switching frequency with the best whistling suppression effect by combining the real-time parameters of the power battery and other inherent parameters. In the case of a limited switching frequency, the real-time switching frequency used to control the operation of the motor system is determined according to the relationship between the candidate switching frequency and the maximum limited switching frequency, so as to ensure the whistling suppression effect while taking into account the switching loss.

[0054] In another exemplary embodiment of this application, how to obtain the current torque and current speed is described in detail; please refer to [link to relevant documentation]. Figure 2 , Figure 2 is based on Figure 1 The exemplary embodiment shown illustrates a flowchart of another control method for a motor system. This control method, in... Figure 1 Based on S110 to S140 shown, at least S210 to S220 are also included, which are described in detail below:

[0055] S210: Determine the current torque of the motor system based on the current original torque request value; wherein, the current original torque request value is derived from the vehicle controller.

[0056] In some embodiments, the current original torque request value is directly used as the current torque of the motor system. In another embodiment, the current original torque request value needs to be calibrated, and the calibrated torque value is used as the current torque to avoid excessive errors caused by inaccurate original torque request values, which would affect the accuracy of subsequent data processing and calculations.

[0057] S220: The original resolver signal is calibrated, and the current rotational speed is determined based on the calibrated original resolver signal.

[0058] To avoid fluctuations in the original resolver signal, this embodiment filters, selects, and calibrates the real-time acquired original resolver signal to improve the accuracy of the resolver signal. The current rotational speed is then determined based on the calibrated original resolver signal, making the current rotational speed more accurate.

[0059] In order to improve the accuracy of the current speed and current torque, this embodiment starts with the relevant original signals, calibrates the original torque request value and the original resolver signal, and then accurately determines the current speed and current torque.

[0060] In another exemplary embodiment of this application, the application scenarios of the above-mentioned multiple control methods are illustrated by way of example. Please refer to the following for details. Figure 3 , Figure 3 This is a schematic diagram illustrating an application scenario of the motor system control method of this application. It includes a vehicle 100 and a server 200, which can be connected wirelessly. This application does not limit the connection method between them.

[0061] Server 200 is the execution entity of the control method illustrated in any of the above exemplary embodiments, and performs any of the above control methods, as illustrated below:

[0062] Server 200 determines the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system. Server 200 calculates the current back electromotive force (EMF) value based on the current speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage. Server 200 calculates the candidate switching frequency based on the current back EMF value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current. If there is a limiting switching frequency, server 200 determines the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency, and controls the operation of the motor system based on the current switching frequency.

[0063] In one exemplary embodiment, such as Figure 4 As shown, the execution logic of server 200 involves the maximum limit switching frequency and the selected switching frequency calculated in real time. When the vehicle has the switching frequency limiting function enabled (i.e., there is a limit to the switching frequency), server 200 determines the current switching frequency based on the relationship between the selected switching frequency and the maximum limit switching frequency.

[0064] Server 200 can be as follows Figure 3 As shown, the server 200 can be located within vehicle 100, or it can be a physical server independent of vehicle 100, or it can be a server cluster or distributed system composed of multiple physical servers. Multiple servers can form a blockchain, and the server is a node on the blockchain. Server 200 can also be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms. This document does not impose any restrictions on this.

[0065] Another aspect of this application provides a control device for an electric motor system, such as... Figure 5 As shown, Figure 5 This is a schematic diagram illustrating the structure of a control device for a motor system according to an exemplary embodiment of this application. The control device 500 includes:

[0066] The determination module 510 is used to determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system.

[0067] The first calculation module 530 is used to calculate the current back electromotive force value based on the current rotational speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance and motor flux linkage.

[0068] The second calculation module 550 is used to calculate the candidate switching frequency based on the current back electromotive force value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current.

[0069] The control module 570 is used to determine the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency if there is a limiting switching frequency, and to control the operation of the motor system based on the current switching frequency.

[0070] In another embodiment, the determining module 510 includes:

[0071] The first determining unit is used to determine the target preset torque range to which the current torque of the motor system belongs, and the target preset speed range to which the current speed belongs.

[0072] The second determining unit is used to determine the target preset operating condition parameter set based on the target preset torque range and the target preset speed range, so as to determine the current direct axis current, the current direct axis inductance, the current quadrature axis current and the current quadrature axis inductance.

[0073] In another embodiment, the first computing module 530 includes:

[0074] The first calculation unit is used to square the product of the current quadrature-axis current and the current quadrature-axis inductance to obtain the first squared value.

[0075] The second calculation unit is used to sum the product of the current direct-axis current and the current direct-axis inductance with the motor flux linkage, and then square the sum to obtain the second squared value.

[0076] The third calculation unit is used to perform a root operation on the sum of the first square value and the second square value, and then multiply the calculated root value with the current rotational speed to obtain the current back electromotive force value.

[0077] In another embodiment, the second computing module 550 includes:

[0078] The fourth calculation unit is used to calculate the difference between the rated voltage of the power battery and the current back electromotive force value.

[0079] The fifth calculation unit is used to multiply the equivalent inductance of the motor system, the maximum preset ripple current, and the preset coefficient to obtain the product; wherein the preset coefficient corresponds to the preset duty cycle.

[0080] The sixth calculation unit is used to divide the difference by the product to obtain the selectable switching frequency.

[0081] In another embodiment, the control module 570 includes:

[0082] The first control unit is used to determine the maximum limiting switching frequency as the current switching frequency if the selected switching frequency is greater than or equal to the maximum limiting switching frequency.

[0083] The second control unit is used to determine the current switching frequency if the selected switching frequency is less than the maximum limiting switching frequency.

[0084] In another embodiment, the control device 500 further includes:

[0085] The torque determination module is used to determine the current torque of the motor system based on the current original torque request value; wherein the current original torque request value comes from the vehicle controller.

[0086] The speed determination module is used to calibrate the original resolver signal and determine the current speed based on the calibrated original resolver signal.

[0087] In another embodiment, the control device 500 further includes:

[0088] An additional control module is used to select the current switching frequency if there is no limiting switching frequency, and to control the operation of the motor system based on the current switching frequency.

[0089] The control device of this application determines the relevant real-time operating parameters of the motor system based on the real-time torque and real-time speed of the motor system, and calculates the candidate switching frequency with the best whistling suppression effect by combining the real-time parameters of the power battery and other inherent parameters. When there is a limiting switching frequency, the real-time switching frequency used to control the operation of the motor system is determined according to the relationship between the candidate switching frequency and the maximum limiting switching frequency, so as to ensure the whistling suppression effect while taking into account the switching loss.

[0090] It should be noted that the control device provided in the above embodiments and the control method provided in the foregoing embodiments belong to the same concept. The specific way in which each module and unit performs operations has been described in detail in the method embodiments, and will not be repeated here.

[0091] Another aspect of this application provides an electronic device, including: a controller; and a memory for storing one or more programs, which, when executed by the controller, perform the control method described above.

[0092] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of a computer system for an electronic device according to an exemplary embodiment of this application, illustrating a schematic diagram of the structure of a computer system suitable for implementing the embodiments of this application.

[0093] It should be noted that, Figure 6 The computer system 600 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0094] like Figure 6As shown, the computer system 600 includes a Central Processing Unit (CPU) 601, which can perform various appropriate actions and processes, such as executing the methods described in the above embodiments, based on programs stored in Read-Only Memory (ROM) 602 or programs loaded from storage portion 608 into Random Access Memory (RAM) 603. The RAM 603 also stores various programs and data required for system operation. The CPU 601, ROM 602, and RAM 603 are interconnected via a bus 604. An Input / Output (I / O) interface 605 is also connected to the bus 604.

[0095] The following components are connected to I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 610 as needed so that computer programs read from it can be installed into storage section 608 as needed.

[0096] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 609, and / or installed from removable medium 611. When the computer program is executed by central processing unit (CPU) 601, it performs various functions defined in the system of this application.

[0097] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. The transmitted data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0098] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0099] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0100] Another aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the control method as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not assembled into the electronic device.

[0101] Another aspect of this application provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the control methods provided in the various embodiments described above.

[0102] According to one aspect of the embodiments of this application, a computer system is also provided, including a Central Processing Unit (CPU), which can perform various appropriate actions and processes based on a program stored in read-only memory (ROM) or a program loaded from storage into random access memory (RAM), such as performing the methods described above. Various programs and data required for system operation are also stored in the RAM. The CPU, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0103] The following components are connected to the I / O interface: input components including keyboards, mice, etc.; output components including cathode ray tubes (CRTs), liquid crystal displays (LCDs), and speakers; storage components including hard drives; and communication components including network interface cards such as LAN (Local Area Network) cards and modems. The communication components perform communication processing via networks such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical discs, magneto-optical discs, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage components as required.

[0104] The above description is merely a preferred exemplary embodiment of this application and is not intended to limit the implementation of this application. Those skilled in the art can easily make corresponding modifications or alterations based on the main concept and spirit of this application. Therefore, the scope of protection of this application should be determined by the scope of protection claimed in the claims.

Claims

1. A control method for a motor system, characterized in that, The control method includes: Based on the current torque and current speed of the motor system, determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance; The current back electromotive force value is calculated based on the current rotational speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage. The candidate switching frequency is calculated based on the current back electromotive force value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current. If there is a limiting switching frequency, the current switching frequency is determined based on the relationship between the candidate switching frequency and the maximum limiting switching frequency, and the motor system is controlled to operate based on the current switching frequency.

2. The control method according to claim 1, characterized in that, The determination of the current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage based on the current torque and current speed of the motor system includes: The target preset torque range to which the current torque of the motor system belongs, and the target preset speed range to which the current speed belongs, are determined respectively; Based on the target preset torque range and the target preset speed range, a target preset operating condition parameter set is determined to determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance.

3. The control method according to claim 1, characterized in that, The calculation of the current back electromotive force value based on the current rotational speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage includes: The product of the current quadrature-axis current and the current quadrature-axis inductance is squared to obtain the first squared value; The product of the current direct-axis current and the current direct-axis inductance is summed with the motor flux linkage, and the sum is squared to obtain the second squared value. The sum of the first squared value and the second squared value is used to perform a root operation, and the calculated root value is multiplied by the current rotational speed to obtain the current back electromotive force value.

4. The control method according to claim 1, characterized in that, The step of calculating the candidate switching frequency based on the current back electromotive force value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current includes: The difference is calculated by subtracting the rated voltage of the power battery from the current back electromotive force value. The equivalent inductance, maximum preset ripple current, and preset coefficient of the motor system are multiplied to obtain the product; wherein the preset coefficient corresponds to the preset duty cycle. Divide the difference by the product to obtain the selectable switching frequency.

5. The control method according to claim 1, characterized in that, The step of determining the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency includes: If the candidate switching frequency is greater than or equal to the maximum limiting switching frequency, then the maximum limiting switching frequency is determined as the current switching frequency; If the candidate switch frequency is less than the maximum limiting switch frequency, then the candidate switch frequency is determined as the current switch frequency.

6. The control method according to any one of claims 1 to 5, characterized in that, The control method further includes: The current torque of the motor system is determined based on the current original torque request value; wherein the current original torque request value is derived from the vehicle controller. The original resolver signal is calibrated, and the current rotational speed is determined based on the calibrated original resolver signal.

7. The control method according to any one of claims 1 to 5, characterized in that, The control method further includes: If the limiting switching frequency does not exist, the candidate switching frequency is used as the current switching frequency, and the motor system is controlled to operate based on the current switching frequency.

8. A control device for a motor system, characterized in that, The control device includes: The determination module is used to determine the current direct-axis current, current direct-axis inductance, current quadrature-axis current, and current quadrature-axis inductance based on the current torque and current speed of the motor system. The first calculation module is used to calculate the current back electromotive force value based on the current rotational speed, current direct-axis current, current direct-axis inductance, current quadrature-axis current, current quadrature-axis inductance, and motor flux linkage. The second calculation module is used to calculate the candidate switching frequency based on the current back electromotive force value, the rated voltage of the power battery, the equivalent inductance of the motor system, and the maximum preset ripple current. The control module is used to determine the current switching frequency based on the relationship between the candidate switching frequency and the maximum limiting switching frequency if there is a limiting switching frequency, and to control the operation of the motor system based on the current switching frequency.

9. An electronic device, characterized in that, include: Controller; A memory for storing one or more programs, which, when executed by a controller, cause the controller to implement the control method of any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores computer-readable instructions that, when executed by the computer's processor, cause the computer to perform the control method described in any one of claims 1 to 7.

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