Pulse width modulation control method and related equipment
By dynamically selecting the pulse width modulation method in combination with the modulation ratio and torque of the motor, the efficiency and stability issues of the traditional pulse width modulation control method under different working conditions are solved, and the motor noise and vibration are suppressed and the electric drive efficiency is improved.
Patent Information
- Application Number
- CN202411886698.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-09-19
- Estimated Expiration
- 2044-12-20
AI Technical Summary
Traditional pulse width modulation control methods are difficult to provide optimal motor control effects under different operating conditions, especially under low load, high torque or high modulation ratio conditions, which leads to reduced motor efficiency, increased switching losses and shaft voltage fluctuations, affecting system performance and reliability.
By dynamically selecting different pulse width modulation methods, combining the modulation ratio and torque of the motor, and using different space vector pulse width modulation and differential pulse width modulation methods, optimized control is performed according to changes in the motor's operating conditions.
Under different working conditions, it not only suppresses the shaft voltage and reduces noise and vibration, but also improves the electric drive efficiency under high load conditions, and improves the accuracy of motor control and the stability of the system.
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Figure CN119727525B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of motor drive control, and more specifically, to a pulse width modulation control method and related equipment. Background Art
[0002] With the continuous advancement of motor drive technology, pulse width modulation (PWM) control methods are playing an increasingly important role in motor control systems, particularly in electric vehicles, power tools, and industrial automation equipment. PWM control methods can precisely regulate a motor's output voltage and power, thereby optimizing its performance. However, because the motor's operating environment and load conditions often exhibit nonlinear characteristics, traditional PWM control methods often struggle to provide optimal control under varying operating conditions.
[0003] In the existing technology, the motor output voltage is usually controlled through a fixed pulse width modulation method, but this control method fails to fully consider the dynamic changes of the motor under different load, modulation ratio and torque conditions. Especially under low load, high torque or high modulation ratio conditions, a single pulse width modulation control method may lead to reduced motor efficiency, increased switching losses, and even unnecessary shaft voltage fluctuations. This simplified control strategy cannot effectively balance the shaft voltage suppression and electric drive efficiency in the electric drive system in some cases, thereby affecting the overall performance and reliability of the system. Therefore, the existing technology faces the technical problem of being unable to accurately control the motor output voltage under different operating conditions. Summary of the Invention
[0004] The Summary of the Invention section of this application introduces a series of simplified concepts that will be further described in detail in the Detailed Description of the Invention section. The Summary of the Invention section of this application is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.
[0005] The pulse width modulation control method and related devices provided in this application can suppress the shaft voltage, reduce noise and vibration, and improve the electric drive efficiency under high load conditions by dynamically selecting different modulation methods and combining the modulation ratio and torque of the motor.
[0006] In a first aspect, the present application provides a pulse width modulation control method, comprising: obtaining a modulation ratio of a target motor in response to an electric drive start signal; obtaining the motor torque of the target motor when the modulation ratio is less than a first preset ratio; controlling the output voltage of the target motor by a first preset space vector pulse width modulation method when the modulation ratio is less than a second preset ratio and the motor torque is less than the preset torque, wherein the second preset ratio is less than the first preset ratio, and the first preset space vector pulse width modulation method is a space vector pulse width modulation method for suppressing the shaft voltage; when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, controlling the output voltage of the target motor by a second preset space vector pulse width modulation method, wherein the second preset space vector pulse width modulation method is a modulation method combining the first preset space vector pulse width modulation method and the differential pulse width modulation method.
[0007] In some embodiments, it also includes: when the modulation ratio is greater than or equal to the first preset ratio and less than a third preset ratio, obtaining the power factor angle of the target motor; when the power factor angle is less than or equal to the first angle, using a first pulse width modulation method to control the output voltage of the target motor, wherein the first pulse width modulation method is a modulation method in which only any phase in an odd voltage vector sector maintains a low level and only any phase in an even voltage vector sector maintains a high level; when the power factor angle is greater than the first angle and less than the second angle, using a second pulse width modulation method to control the output voltage of the target motor. The output voltage of the target motor is controlled by adopting a third pulse width modulation method, wherein the second pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a low level in the first half and a high level in the second half, and only any one phase in the even voltage vector sector maintains a low level in the first half and a high level in the second half; when the power factor angle is greater than or equal to the second angle, the output voltage of the target motor is controlled by adopting a third pulse width modulation method, wherein the third pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a high level, and only any one phase in the even voltage vector sector maintains a low level.
[0008] In some embodiments, the first preset ratio is 1, the second preset ratio is 0.78, the third preset ratio is 1.15, the first angle is -30 degrees, the second angle is 30 degrees, and the preset torque is 100 Newton meters.
[0009] In some embodiments, the second preset space vector pulse width modulation mode includes a third preset space vector pulse width modulation mode, and the third preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a first proportion and the differential pulse width modulation mode accounts for a second proportion, and the first proportion is smaller than the second proportion; when the modulation ratio is greater than or equal to the second preset ratio and smaller than the first preset ratio, or the modulation ratio is smaller than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the second preset space vector pulse width modulation mode, including: when the modulation ratio is greater than or equal to the second preset ratio and smaller than the first preset ratio, and the motor torque is smaller than the preset torque, the output voltage of the target motor is controlled by the third preset space vector pulse width modulation mode.
[0010] In some embodiments, the second preset space vector pulse width modulation mode also includes a fourth preset space vector pulse width modulation mode, and the fourth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a third proportion and the differential pulse width modulation mode accounts for a fourth proportion, and the third proportion is greater than the fourth proportion; when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the second preset space vector pulse width modulation mode, and also includes: when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fourth preset space vector pulse width modulation mode.
[0011] In some embodiments, the second preset space vector pulse width modulation mode also includes a fifth preset space vector pulse width modulation mode, and the fifth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a fifth proportion and the differential pulse width modulation mode accounts for a sixth proportion, the fifth proportion is smaller than the first proportion, and the sixth proportion is larger than the second proportion; when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the second preset space vector pulse width modulation mode, and also includes: when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fifth preset space vector pulse width modulation mode.
[0012] In some embodiments, the first ratio is 1 / 3, the second ratio is 2 / 3, the third ratio is 2 / 3, the fourth ratio is 1 / 3, the fifth ratio is 1 / 4, and the sixth ratio is 3 / 4.
[0013] In a second aspect, the present application also provides a pulse width modulation control device, comprising: a modulation ratio acquisition unit for acquiring the modulation ratio of a target motor in response to an electric drive start signal; a torque acquisition unit for acquiring the motor torque of the target motor when the modulation ratio is less than a first preset ratio; a modulation unit for controlling the output voltage of the target motor through a first preset space vector pulse width modulation method when the modulation ratio is less than a second preset ratio and the motor torque is less than the preset torque, wherein the second preset ratio is less than the first preset ratio, and the first preset space vector pulse width modulation method is a space vector pulse width modulation method for suppressing the shaft voltage; the modulation unit is also used to control the output voltage of the target motor through a second preset space vector pulse width modulation method when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, wherein the second preset space vector pulse width modulation method is a modulation method combining the first preset space vector pulse width modulation method and the differential pulse width modulation method.
[0014] In a third aspect, the present application further provides an electronic device comprising: a memory and a processor, wherein the processor is configured to implement the steps of the pulse width modulation control method described in the first aspect when executing a computer program stored in the memory.
[0015] In a fourth aspect, the present application further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the pulse width modulation control method described in the first aspect.
[0016] In a fifth aspect, the present application also provides a computer program product, including a computer program or computer executable instructions, which, when executed by a processor, implements the pulse width modulation control method provided in an embodiment of the present application.
[0017] In summary, the present application determines the pulse width modulation method to be used by combining the modulation ratio and motor torque of the motor, and can dynamically adapt to the needs of different working conditions; in low modulation ratio and low torque working conditions, the first preset space vector pulse width modulation method is adopted, whose main feature is shaft voltage suppression, reducing high-frequency oscillations in the motor axis, and helping to reduce motor noise and vibration; in higher modulation ratio or higher torque working conditions, the second preset space vector pulse width modulation method is adopted, which combines the first preset space vector pulse width modulation method and the differential pulse width modulation method, taking into account shaft voltage suppression and improving the efficiency of the electric drive system. In summary, the pulse width modulation control method provided by the present application dynamically selects different modulation methods, combined with the modulation ratio and torque of the motor, to suppress the shaft voltage, reduce noise and vibration, and improve the electric drive efficiency under high load conditions. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present description. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:
[0019] Figure 1 A flow chart of a pulse width modulation control method provided in an embodiment of the present application;
[0020] Figure 2 A schematic diagram of the structure of a pulse width modulation control device provided in an embodiment of the present application;
[0021] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0022] Terms in the specification, claims, and drawings of this application, such as "first," "second," "third," "fourth," and the like (if any), are used to distinguish between similar objects, rather than to describe a particular order or precedence. Therefore, it is understood that these terms can be used interchangeably where appropriate, so that the embodiments described can be implemented in a different order, unless otherwise specified in the drawings or descriptions. In addition, the terms "is" and "has" and any variations thereof in this application are intended to cover all possible constituent elements on a non-exclusive basis. For example, a process, method, system, product, or apparatus that includes several steps or units is not necessarily limited to the steps or units that are explicitly listed, but may also include other steps or units that are not explicitly listed, or steps or units that are inherent to the process, method, product, or apparatus.
[0023] In this application, a "module" or "unit" refers to a computer program or part of a computer program that has a specific function and works in conjunction with other related parts to achieve a predetermined goal. These modules or units can be implemented by software, hardware (such as processing circuits or memories), or a combination of the two. One or more processors or memories can implement one or more modules or units. At the same time, each module or unit can also be part of a larger module or unit.
[0024] The technical solutions in this application will be described in detail below in conjunction with the accompanying drawings in the embodiments. It should be noted that the embodiments described are only part of this application, not all embodiments. In the following description, the "some embodiments" mentioned are only a subset of all possible embodiments, which may be the same or different subsets, and different embodiments can be combined with each other without conflict.
[0025] See also Figure 1 , Figure 1 1 is a flow chart of a pulse width modulation control method provided in an embodiment of the present application. The method may specifically include the following steps 101 to 104:
[0026] Step 101, in response to an electric drive start signal, obtaining a modulation ratio of a target motor;
[0027] In some examples, the electric drive start signal is a control signal used to start the target motor. It can be issued by an electronic control unit (ECU) or a higher-level control system to instruct the target motor to begin operation. This signal is typically generated by a sensor, switch, or by the control system through software, and is triggered by controlling the start-up process of the electric drive system. For example, in an electric vehicle, pressing the "Start" button generates an electric drive start signal, triggering the motor start process. The target motor is the motor to be controlled, typically the main motor or drive motor in the electric drive system. For example, in an electric vehicle, the target motor may be the motor that drives the vehicle. In an autonomous driving system, the specific drive motor is selected through a control signal. The modulation ratio refers to the duty cycle of the motor control signal, representing the ratio of voltage or power provided by the motor control system to the target motor. The modulation ratio reflects the load and control mode of the target motor during operation. For example, assuming the duty cycle of the motor control signal is 50%, that is, the modulation ratio is 0.5, indicating that the control system provides half of the maximum voltage to the motor.
[0028] By implementing step 101, the modulation ratio is obtained to provide basic information for subsequent pulse width modulation mode selection, ensuring that reasonable motor control can be performed according to actual needs during the electric drive startup phase.
[0029] Step 102 , when the modulation ratio is less than a first preset ratio, obtaining the motor torque of the target motor;
[0030] In some examples, the first preset ratio is a preset value used to determine whether the modulation ratio has reached a certain threshold. The first preset ratio can be set based on specific control needs and system performance requirements to determine when a specific control strategy should be adopted. For example, assuming the first preset ratio is set to 0.8, this means that if the modulation ratio is less than 0.8, a specific control mode will be entered. Motor torque refers to the actual or expected output torque of the target motor under the current operating conditions. Motor torque is generally a dynamic variable related to factors such as current, speed, and load. Motor torque can be calculated based on the speed, phase current, and other sensor data of the target motor.
[0031] The implementation of step 102 helps to more accurately determine the load condition of the motor under low modulation ratios. Since a low modulation ratio usually means that the motor load is light or is in a low speed state, the acquisition of torque can provide a more comprehensive basis for the subsequent adjustment of the pulse width modulation method, ensuring the working stability and reliability of the target motor under different load conditions.
[0032] Step 103 , when the modulation ratio is less than the second preset ratio and the motor torque is less than the preset torque, controlling the output voltage of the target motor by using a first preset space vector pulse width modulation method;
[0033] The second preset ratio is smaller than the first preset ratio, and the first preset space vector pulse width modulation mode is a space vector pulse width modulation mode for suppressing the shaft voltage;
[0034] In some examples, the second preset ratio is another threshold for determining the magnitude of the modulation ratio, which is less than the first preset ratio and is used to further refine the switching of the control strategy, helping to flexibly adjust the control strategy under different working conditions and ensure the accuracy and efficiency of motor control. The preset torque is a threshold set for the motor. Whether the motor torque is less than or greater than this value determines whether a different adjustment strategy needs to be adopted; for example, assuming the preset torque is set to 100Nm, this means that a specific control strategy is executed when the output torque of the motor is less than 100Nm. The shaft voltage refers to the voltage applied to the motor shaft, which is usually adjusted by a combination of current and voltage. Excessive shaft voltage can cause motor vibration and noise; Space Vector Pulse Width Modulation (SVPWM) is a modulation technology used to generate an AC voltage waveform in a multi-phase motor drive; the first preset space vector pulse width modulation method is a space vector pulse width modulation method designed to control the output voltage of the motor. The first preset space vector pulse width modulation method will suppress the shaft voltage to reduce high-frequency oscillations in the motor axis, thereby effectively reducing motor noise and vibration.
[0035] Exemplarily, when the modulation ratio is less than a second preset ratio (such as 0.78) and the motor torque is less than a preset torque (such as 100 Nm), the control system will select the first preset space vector pulse width modulation method to control the output voltage of the target motor. In this process, the first preset space vector pulse width modulation method will be used to optimize the voltage output of the motor, especially by suppressing the shaft voltage and reducing the high-frequency oscillation of the motor axial direction.
[0036] The order of sector vector action of the space vector pulse width modulation method in the related art is shown in Table 1, while the order of sector vector action of the first preset space vector pulse width modulation method provided in the embodiment of the present application is shown in Table 1.
[0037] As shown in Table 2.
[0038]
[0039] Table 1 Conventional space vector pulse width modulation sector sequence table
[0040]
[0041]
[0042] Table 2 First preset space vector pulse width modulation sector sequence table
[0043] The three-digit numbers in the table consist of three binary digits (e.g., "101"), each corresponding to a target motor phase (typically A, B, and C). The first digit represents the voltage state of phase A (e.g., high or low), the second digit represents the voltage state of phase B, and the third digit represents the voltage state of phase C. For example, "101" indicates that phase A is high, phase B is low, and phase C is high. The "sectors" in the table refer to the six distinct regions corresponding to the voltage vector. These sectors are formed by dividing the three-phase coordinate system (i.e., the voltages of phases A, B, and C) at different angles to describe different voltage states of the target motor. Assume a standard coordinate system in which the X-axis and Y-axis represent the vector components of the A and B phase voltages, respectively. The vector of the third phase voltage is determined by their relationship. These vectors are divided into six sectors: sector 1 (0° to 60°), sector 2 (60° to 120°), sector 3 (120° to 180°), sector 4 (180° to 240°), sector 5 (240° to 300°), and sector 6 (300° to 360°).
[0044] Through the implementation of step 103, the first preset space vector pulse width modulation method has a shaft voltage suppression characteristic, which can effectively reduce the axial high-frequency oscillation of the motor and reduce noise and vibration; under low load conditions, the shaft voltage suppression can improve the stability of the motor and avoid instability caused by excessive vibration, thereby improving the comfort and reliability of the target motor operation.
[0045] Step 104: When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, controlling the output voltage of the target motor by a second preset space vector pulse width modulation method;
[0046] The second preset space vector pulse width modulation mode is a modulation mode combining the first preset space vector pulse width modulation mode and the differential pulse width modulation mode;
[0047] In some examples, differential pulse width modulation (DPWM) is a pulse width modulation technology that adjusts the voltage output by changing the time difference between two pulses; this method can reduce high-frequency noise, improve harmonic characteristics, and enhance the stability of the motor control system; the second preset space vector pulse width modulation method is based on a control strategy for modulating the motor output voltage, combining the first preset space vector pulse width modulation method with the differential pulse width modulation method to obtain a more optimized voltage waveform.
[0048] Exemplarily, when the modulation ratio is between a first preset ratio (such as 1) and a second preset ratio (such as 0.78) or the motor torque is greater than a set threshold, the motor voltage output is optimized by a second preset space vector pulse width modulation method.
[0049] Through the implementation of step 104, the second preset space vector pulse width modulation method combines the first preset space vector pulse width modulation and the differential pulse width modulation method, which can not only suppress shaft voltage fluctuations but also improve system efficiency; under these operating conditions, the motor requires a more precise control strategy to maintain high efficiency. The introduction of the second preset space vector pulse width modulation method can effectively improve the efficiency of the electric drive system, reduce unnecessary losses, and ensure the stable performance of the target motor.
[0050] In summary, the embodiment of the present application determines the pulse width modulation method to be used by combining the modulation ratio and motor torque of the motor, and can dynamically adapt to the needs of different working conditions; in low modulation ratio and low torque working conditions, the first preset space vector pulse width modulation method is adopted, whose main feature is shaft voltage suppression, reducing high-frequency oscillations in the motor axis, and helping to reduce motor noise and vibration; in higher modulation ratio or higher torque working conditions, the second preset space vector pulse width modulation method is adopted, which combines the first preset space vector pulse width modulation method and the differential pulse width modulation method, taking into account shaft voltage suppression and improving the efficiency of the electric drive system. In summary, the pulse width modulation control method provided by the embodiment of the present application dynamically selects different modulation methods, combined with the modulation ratio and torque of the motor, to suppress the shaft voltage, reduce noise and vibration, and improve the electric drive efficiency under high load conditions.
[0051] In some embodiments, the present invention may further include: when the modulation ratio is greater than or equal to the first preset ratio and less than the third preset ratio, obtaining the power factor angle of the target motor; when the power factor angle is less than or equal to the first angle, using the first pulse width modulation method to control the output voltage of the target motor, wherein the first pulse width modulation method is a modulation method in which only any phase in the odd voltage vector sector maintains a low level and only any phase in the even voltage vector sector maintains a high level; when the power factor angle is greater than the first angle and less than the second angle, using the second pulse width modulation method to control the output voltage of the target motor. The output voltage of the target motor is controlled by adopting a third pulse width modulation method, wherein the second pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a low level in the first half and a high level in the second half, and only any one phase in the even voltage vector sector maintains a low level in the first half and a high level in the second half; when the power factor angle is greater than or equal to the second angle, the output voltage of the target motor is controlled by adopting a third pulse width modulation method, wherein the third pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a high level, and only any one phase in the even voltage vector sector maintains a low level.
[0052] In some examples, the power factor angle is typically used to describe the phase difference between the current and voltage in the target motor, reflecting the power factor of the target motor under different loads, that is, the phase difference between the voltage and current. The power factor angle can be detected by current and voltage sensors to detect the actual operating state of the target motor and extracted using Fourier transform or phase detection. For example, assuming that the phase difference between the voltage waveform and the current waveform of the target motor is 30°, the power factor angle is 30°. The first pulse width modulation mode is a modulation mode in which only one phase maintains a low level in odd-numbered voltage vector sectors and only one phase maintains a high level in even-numbered voltage vector sectors. When the power factor angle of the target motor is less than or equal to the first angle, the modulator selects this mode based on the motor state, that is, it is used for load conditions with a low power factor angle. The second PWM mode maintains a low level for the first half of any phase in odd-numbered voltage vector sectors and a high level for the second half. Similarly, in even-numbered voltage vector sectors, any phase maintains a low level for the first half and a high level for the second half. This mode is selected when the target motor's power factor angle is greater than the first angle and less than the second angle, accommodating loads with medium power factor angles. The third PWM mode maintains a high level for odd-numbered voltage vector sectors and a low level for even-numbered voltage vector sectors. This mode is selected when the target motor's power factor angle is greater than or equal to the second angle, suitable for loads with higher power factor angles.
[0053] Through the implementation of the above embodiments, the influence of the motor power factor angle is further considered; when the power factor angle is small, the first pulse width modulation method is adopted to optimize the response of the motor and reduce unnecessary losses; when the power factor angle is large, the third pulse width modulation method is adopted to improve the efficiency of the motor and reduce unnecessary high-frequency fluctuations; dynamically switching the pulse width modulation method according to the power factor angle can further improve the adaptability and efficiency of the electric drive system.
[0054] In some embodiments, the first preset ratio is 1, the second preset ratio is 0.78, the third preset ratio is 1.15, the first angle is -30 degrees, the second angle is 30 degrees, and the preset torque is 100 Newton meters.
[0055] By implementing the above embodiments, it is possible to more accurately adapt to the motor control requirements under different working conditions. This quantitative parameter configuration can ensure the switching of pulse width modulation modes under different loads and working conditions, thereby improving the control accuracy and response speed of the target motor.
[0056] In some embodiments, the aforementioned second preset space vector pulse width modulation mode may include a third preset space vector pulse width modulation mode, and the aforementioned third preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a first proportion, and the differential pulse width modulation mode accounts for a second proportion, and the first proportion is less than the second proportion; step 104 may include: when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is less than the preset torque, the output voltage of the target motor is controlled by the third preset space vector pulse width modulation mode.
[0057] In some examples, the third preset space vector pulse width modulation method is a modulation method that combines the first preset space vector pulse width modulation method and the differential pulse width modulation method; in the implementation process, the first preset space vector pulse width modulation method accounts for a first proportion (such as 1 / 3), and the differential pulse width modulation method accounts for a second proportion (such as 2 / 3); if the modulation ratio is between the second preset ratio and the first preset ratio, and the motor torque is less than the preset torque, this modulation method is selected.
[0058] By implementing the above embodiment, the ratio of the first pulse width modulation mode to the differential pulse width modulation mode is adjusted, so that the motor output voltage can be adjusted more flexibly, and the motor efficiency and shaft voltage suppression effect can be optimized.
[0059] In some embodiments, the aforementioned second preset space vector pulse width modulation mode may further include a fourth preset space vector pulse width modulation mode, and the aforementioned fourth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a third proportion (such as 2 / 3), and the differential pulse width modulation mode accounts for a fourth proportion (such as 1 / 3), and the third proportion is greater than the fourth proportion; step 104 may further include: when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fourth preset space vector pulse width modulation mode.
[0060] In some examples, the fourth preset space vector pulse width modulation mode is a modulation mode further than the third preset space vector pulse width modulation mode, and the ratio of the first preset space vector pulse width modulation mode to the differential pulse width modulation mode is adjusted. During the implementation process, the proportion of the first preset space vector pulse width modulation mode is the third proportion, and the proportion of the differential pulse width modulation mode is the fourth proportion; when the modulation ratio is less than the second preset ratio (such as 0.78) and the motor torque is greater than or equal to the preset torque (such as 100 Newton meters), the fourth preset space vector pulse width modulation mode is selected.
[0061] Through the implementation of the above embodiment, the fourth preset space vector pulse width modulation mode is introduced, so that under a wider range of working conditions, the combination ratio of the pulse width modulation modes, that is, the ratio of the first pulse width modulation mode and the differential pulse width modulation mode, can be accurately adjusted to meet the requirements of different motor loads and modulation ratios, ensuring that higher efficiency and lower switching losses can be achieved under different working conditions.
[0062] In some embodiments, the aforementioned second preset space vector pulse width modulation mode may further include a fifth preset space vector pulse width modulation mode, and the aforementioned fifth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a fifth proportion (such as 1 / 4), and the differential pulse width modulation mode accounts for a sixth proportion (such as 3 / 4), the fifth proportion is smaller than the first proportion, and the sixth proportion is greater than the second proportion; step 104 may further include: when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fifth preset space vector pulse width modulation mode.
[0063] In some examples, the fifth preset space vector pulse width modulation mode is a more refined modulation mode following the fourth preset space vector pulse width modulation mode, which further adjusts the ratio of the first preset space vector pulse width modulation mode to the differential pulse width modulation mode: the time or period of the first space vector pulse width modulation mode accounts for the fifth ratio, while the time or period of the differential pulse width modulation mode accounts for the sixth ratio; when the modulation ratio is greater than or equal to the second preset ratio (such as 0.78) and less than the first preset ratio (such as 1), and the motor torque is greater than or equal to the preset torque (such as 100 Newton meters), the fifth preset space vector pulse width modulation mode is selected.
[0064] Through the implementation of the above embodiments, a fifth preset space vector pulse width modulation method is further introduced, and the proportion is finely divided, so that under different modulation ratios and motor torque conditions, more accurate pulse width modulation method selection can be achieved, and the stability and efficiency of motor control are optimized, especially under high load or complex working conditions, to ensure that the electric drive system maintains optimal performance.
[0065] In some embodiments, the first ratio is 1 / 3, the second ratio is 2 / 3, the third ratio is 2 / 3, the fourth ratio is 1 / 3, the fifth ratio is 1 / 4, and the sixth ratio is 3 / 4.
[0066] Through the implementation of the above embodiments, the effects of various pulse width modulation methods can be accurately adjusted under different modulation ratios, power factor angles and torque conditions, thereby improving the efficiency of the electric drive system of the target motor and reducing the energy loss and noise of the target motor.
[0067] Furthermore, as an implementation of the aforementioned method embodiment, the present application also provides a pulse width modulation control device for implementing the aforementioned method embodiment. This device embodiment corresponds to the aforementioned method embodiment. For ease of reading, this pulse width modulation control device embodiment will no longer describe the details of the aforementioned method embodiment one by one, but it should be clear that the device in the embodiment of the present application can implement all the contents of the aforementioned method embodiment. Figure 2 As shown, the pulse width modulation control device 20 includes: a modulation ratio acquisition unit 201, a torque acquisition unit 202 and a modulation unit 203, wherein the modulation ratio acquisition unit 201 is used to obtain the modulation ratio of the target motor in response to the electric drive start signal; the torque acquisition unit 202 is used to obtain the motor torque of the target motor when the modulation ratio is less than a first preset ratio; the modulation unit 203 is used to control the output voltage of the target motor through a first preset space vector pulse width modulation mode when the modulation ratio is less than a second preset ratio and the motor torque is less than the preset torque, wherein the second preset ratio is less than the first preset ratio, and the first preset space vector pulse width modulation mode is a space vector pulse width modulation mode that suppresses the shaft voltage; the modulation unit 203 is further used to control the output voltage of the target motor through a second preset space vector pulse width modulation mode when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, wherein the second preset space vector pulse width modulation mode is a modulation mode that combines the first preset space vector pulse width modulation mode with the differential pulse width modulation mode.
[0068] In some embodiments, the modulation unit 203 is further used to obtain the power factor angle of the target motor when the modulation ratio is greater than or equal to the first preset ratio and less than the third preset ratio; when the power factor angle is less than or equal to the first angle, the output voltage of the target motor is controlled by a first pulse width modulation method, wherein the first pulse width modulation method is a modulation method in which only any phase in the odd voltage vector sector maintains a low level and only any phase in the even voltage vector sector maintains a high level; when the power factor angle is greater than the first angle and less than the second angle, the target motor is controlled by a second pulse width modulation method. The output voltage of the target motor is controlled by a third pulse width modulation method, wherein the second pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a low level in the first half and a high level in the second half, and in the even voltage vector sector only any one phase maintains a low level in the first half and a high level in the second half; when the power factor angle is greater than or equal to the second angle, the output voltage of the target motor is controlled by a third pulse width modulation method, wherein the third pulse width modulation method is a modulation method in which only any one phase in the odd voltage vector sector maintains a high level, and in the even voltage vector sector only any one phase maintains a low level.
[0069] In some embodiments, the first preset ratio is 1, the second preset ratio is 0.78, the third preset ratio is 1.15, the first angle is -30 degrees, the second angle is 30 degrees, and the preset torque is 100 Newton meters.
[0070] In some embodiments, the second preset space vector pulse width modulation mode includes a third preset space vector pulse width modulation mode, and the third preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a first proportion and the differential pulse width modulation mode accounts for a second proportion, and the first proportion is less than the second proportion; the modulation unit 203 is also used to control the output voltage of the target motor through the third preset space vector pulse width modulation mode when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is less than the preset torque.
[0071] In some embodiments, the second preset space vector pulse width modulation mode also includes a fourth preset space vector pulse width modulation mode, and the fourth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a third proportion, and the differential pulse width modulation mode accounts for a fourth proportion, and the third proportion is greater than the fourth proportion; the modulation unit 203 is also used to control the output voltage of the target motor through the fourth preset space vector pulse width modulation mode when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque.
[0072] In some embodiments, the second preset space vector pulse width modulation mode also includes a fifth preset space vector pulse width modulation mode, and the fifth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for the fifth proportion and the differential pulse width modulation mode accounts for the sixth proportion, the fifth proportion is smaller than the first proportion, and the sixth proportion is greater than the second proportion; the modulation unit 203 is also used to control the output voltage of the target motor through the fifth preset space vector pulse width modulation mode when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is greater than or equal to the preset torque.
[0073] In some embodiments, the first ratio is 1 / 3, the second ratio is 2 / 3, the third ratio is 2 / 3, the fourth ratio is 1 / 3, the fifth ratio is 1 / 4, and the sixth ratio is 3 / 4.
[0074] The present application also provides a computer-readable storage medium storing computer-executable instructions or a computer program. When the computer-executable instructions or the computer program are executed by a processor, the processor will be caused to execute any step of the pulse width modulation control method provided in the present application.
[0075] In some embodiments, the computer-readable storage medium may be a memory such as RAM, read-only memory (ROM), flash memory, magnetic surface memory, optical disk, or compact disc read-only memory (CD-ROM); or it may be various devices including one or any combination of the above memories.
[0076] In some embodiments, computer-executable instructions may be in the form of a program, software, software module, script, or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.
[0077] In some embodiments, computer-executable instructions may, but need not, correspond to a file in a file system, may be stored as part of a file that stores other programs or data, for example, in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinating files (for example, files storing one or more modules, subroutines, or code portions).
[0078] In some embodiments, computer-executable instructions may be deployed to be executed on one electronic device, or on multiple electronic devices located at one site, or on multiple electronic devices distributed across multiple sites and interconnected by a communication network.
[0079] like Figure 3 As shown, the present application also provides an electronic device 30, including a memory 310, a processor 320 and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, any step of the above-mentioned pulse width modulation control method is implemented.
[0080] The present application also provides a computer program product, which includes a computer program or computer-executable instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer program or computer-executable instructions from the computer-readable storage medium and executes the computer program or computer-executable instructions, causing the electronic device to perform any step of the pulse width modulation control method described above.
[0081] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A pulse width modulation control method, characterized in that: include: In response to the electric drive start signal, obtaining a modulation ratio of the target motor; When the modulation ratio is less than a first preset ratio, obtaining the motor torque of the target motor; When the modulation ratio is less than a second preset ratio and the motor torque is less than a preset torque, the output voltage of the target motor is controlled by a first preset space vector pulse width modulation mode, wherein the second preset ratio is less than the first preset ratio, and the first preset space vector pulse width modulation mode is a space vector pulse width modulation mode that suppresses the shaft voltage; When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by a second preset space vector pulse width modulation method, wherein the second preset space vector pulse width modulation method is a modulation method that combines the first preset space vector pulse width modulation method with a differential pulse width modulation method.
2. The pulse width modulation control method according to claim 1, characterized in that: Also includes: When the modulation ratio is greater than or equal to the first preset ratio and less than a third preset ratio, obtaining a power factor angle of the target motor; When the power factor angle is less than or equal to a first angle, a first pulse width modulation method is used to control the output voltage of the target motor, wherein the first pulse width modulation method is a modulation method in which only any phase in an odd-numbered voltage vector sector maintains a low level and only any phase in an even-numbered voltage vector sector maintains a high level; When the power factor angle is greater than the first angle and less than the second angle, a second pulse width modulation method is used to control the output voltage of the target motor, wherein the second pulse width modulation method is a modulation method in which only any phase in an odd-numbered voltage vector sector maintains a low level in the first half and a high level in the second half, and in an even-numbered voltage vector sector, only any phase maintains a low level in the first half and a high level in the second half; When the power factor angle is greater than or equal to the second angle, a third pulse width modulation method is used to control the output voltage of the target motor, wherein the third pulse width modulation method is a modulation method in which only any phase in an odd-numbered voltage vector sector maintains a high level and only any phase in an even-numbered voltage vector sector maintains a low level.
3. The pulse width modulation control method according to claim 2, characterized in that: The first preset ratio is 1, the second preset ratio is 0.78, the third preset ratio is 1.15, the first angle is -30 degrees, the second angle is 30 degrees, and the preset torque is 100 Newton meters.
4. The pulse width modulation control method according to any one of claims 1 to 3, characterized in that: The second preset space vector pulse width modulation mode includes a third preset space vector pulse width modulation mode, wherein the third preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a first proportion and the differential pulse width modulation mode accounts for a second proportion, and the first proportion is smaller than the second proportion; When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, controlling the output voltage of the target motor by using a second preset space vector pulse width modulation method includes: When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is less than the preset torque, the output voltage of the target motor is controlled by the third preset space vector pulse width modulation method.
5. The pulse width modulation control method according to claim 4, characterized in that: The second preset space vector pulse width modulation mode further includes a fourth preset space vector pulse width modulation mode, wherein the fourth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a third ratio and the differential pulse width modulation mode accounts for a fourth ratio, and the third ratio is greater than the fourth ratio; When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by a second preset space vector pulse width modulation mode, further comprising: When the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fourth preset space vector pulse width modulation method.
6. The pulse width modulation control method according to claim 5, characterized in that: The second preset space vector pulse width modulation mode further includes a fifth preset space vector pulse width modulation mode, wherein the fifth preset space vector pulse width modulation mode is a modulation mode in which the first preset space vector pulse width modulation mode accounts for a fifth ratio and the differential pulse width modulation mode accounts for a sixth ratio, the fifth ratio being smaller than the first ratio and the sixth ratio being larger than the second ratio; When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by a second preset space vector pulse width modulation mode, further comprising: When the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, and the motor torque is greater than or equal to the preset torque, the output voltage of the target motor is controlled by the fifth preset space vector pulse width modulation method.
7. The pulse width modulation control method according to claim 6, characterized in that: The first ratio is 1 / 3, the second ratio is 2 / 3, the third ratio is 2 / 3, the fourth ratio is 1 / 3, the fifth ratio is 1 / 4, and the sixth ratio is 3 / 4.
8. A pulse width modulation control device, characterized in that: include: a modulation ratio acquisition unit, configured to acquire a modulation ratio of a target motor in response to an electric drive start signal; a torque acquisition unit, configured to acquire the motor torque of the target motor when the modulation ratio is less than a first preset ratio; a modulation unit, configured to control the output voltage of the target motor by a first preset space vector pulse width modulation mode when the modulation ratio is less than a second preset ratio and the motor torque is less than a preset torque, wherein the second preset ratio is less than the first preset ratio, and the first preset space vector pulse width modulation mode is a space vector pulse width modulation mode that suppresses the shaft voltage; The modulation unit is further configured to control the output voltage of the target motor through a second preset space vector pulse width modulation method when the modulation ratio is greater than or equal to the second preset ratio and less than the first preset ratio, or when the modulation ratio is less than the second preset ratio and the motor torque is greater than or equal to the preset torque, wherein the second preset space vector pulse width modulation method is a modulation method that combines the first preset space vector pulse width modulation method with a differential pulse width modulation method.
9. An electronic device comprising: A memory and a processor, wherein the processor is configured to implement the steps of the pulse width modulation control method according to any one of claims 1 to 7 when executing a computer program stored in the memory.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the pulse width modulation control method according to any one of claims 1 to 7 are implemented.
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