Harmonic injection method and device, electronic equipment and storage medium

Abstract

The invention provides a harmonic injection method and device, electronic equipment and a storage medium, and relates to the technical field of electric drive. The method comprises the steps of determining a current rotating speed interval of a motor rotating speed, and determining a harmonic injection mode according to the current rotating speed interval; and when the rotating speed of the motor is switched from the current rotating speed interval to other rotating speed intervals, the harmonic injection mode is switched to be matched with the other rotating speed intervals, and the final injection voltage value when the current rotating speed interval is switched is equal to the initial injection voltage value when the current rotating speed interval is switched to other rotating speed intervals. According to the method, corresponding harmonic injection modes are determined for different motor rotating speeds, the adaptability to batch production scatter difference of an electric drive system is good, the current feedback control precision is high, the injection effect is stable, the low-frequency noise suppression effect is excellent, the method is not limited by the bandwidth of a current loop, the method is suitable for a full-speed domain, and the high-speed noise suppression capability can be ensured; and the NVH performance of the electric drive system is effectively ensured by ensuring that the injection voltage values before and after switching are consistent.

Description

Technical Field

[0001] The present invention relates to the technical field of electric drive, and in particular, to a harmonic injection method, device, electronic device, and storage medium. Background Art

[0002] The whistling noise in an electric drive system refers to the high-frequency noise generated during the operation of the motor due to factors such as electromagnetic excitation, high-order harmonics, or mechanical vibration. Its frequency is usually in the range of 1 kHz to 10 kHz, with the characteristics of being sharp and harsh, easy to be perceived by passengers, and seriously affecting the NVH (Noise, Vibration, Harshness) comfort of the whole vehicle.

[0003] In the related art, harmonic injection can be used to cancel the vibration noise caused by the nonlinear characteristics of the motor. For example, by injecting non-ideal harmonic signals (voltage or current) with specific frequencies into the motor through an inverter, and using the electromagnetic force waves of these harmonic signals to cancel the inherent harmonic excitation of the motor, so as to achieve the effect of suppressing noise. However, in different application scenarios, the fixed harmonic injection method in the related art has poor adaptability, and the harmonic injection effect cannot reach the expected effect. Summary of the Invention

[0004] The problem solved by the present invention is how to improve the suppression effect of high-order harmonic noise in different application scenarios.

[0005] To solve the above problems, the present invention provides a harmonic injection method, device, electronic device, and storage medium.

[0006] In a first aspect, the present invention provides a harmonic injection method, including:

[0007] Determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range;

[0008] When the motor speed switches from the current speed range to other speed ranges, switch the harmonic injection method to match the other speed ranges, wherein the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed ranges.

[0009] Optionally, the harmonic injection method includes a closed-loop current injection method and an open-loop voltage injection method. The determining the harmonic injection method according to the current speed range includes:

[0010] When the current speed range is a speed range less than a preset threshold, execute the closed-loop current injection method;

[0011] When the current speed range is a speed range greater than or equal to the preset threshold, execute the open-loop voltage injection method.

[0012] Optionally, the implementation of the closed-loop current injection method includes:

[0013] Determine the injection current amplitude and injection current phase according to the motor speed and motor torque;

[0014] Determine the injection current components in the dq coordinate system according to the injection current amplitude and the injection current phase;

[0015] Perform harmonic injection according to the injection current components.

[0016] Optionally, the performing harmonic injection according to the injection current components includes:

[0017] Compare the injection current components with the feedback harmonic current, and input the difference signal between the injection current components and the feedback harmonic current into a PI regulator to determine the high-order harmonic voltage signal;

[0018] Use the inverse Park transformation to convert the high-order harmonic voltage signal into harmonic voltage components, determine the comprehensive voltage signal to be loaded to the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal to the motor;

[0019] Wherein, the feedback harmonic current is determined by performing Park transformation on the fundamental current component based on the fundamental electrical angle.

[0020] Optionally, the implementation of the open-loop voltage injection method includes:

[0021] Determine the injection voltage amplitude and injection voltage phase according to the motor speed and motor torque;

[0022] Determine the injection voltage components in the dq coordinate system according to the injection voltage amplitude and the injection voltage phase;

[0023] Perform harmonic injection according to the injection voltage components.

[0024] Optionally, the performing harmonic injection according to the injection voltage components includes:

[0025] Based on the fundamental electrical angle, use the inverse Park transformation to convert the injection voltage components into harmonic voltage components, determine the comprehensive voltage signal to be loaded to the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal to the motor.

[0026] Optionally, when the motor speed switches from the current speed range to other speed ranges, switching the harmonic injection method to match the other speed ranges includes:

[0027] When the rotational speed of the motor switches from a rotational speed range less than the preset threshold to a rotational speed range greater than or equal to the preset threshold, switch the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method;

[0028] When the rotational speed of the motor switches from a rotational speed range greater than or equal to the preset threshold to a rotational speed range less than the preset threshold, switch the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method.

[0029] Optionally, the switching of the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method includes:

[0030] Adjust the initial injection voltage value of the open-loop voltage injection method to be consistent with the final injection voltage value of the closed-loop current injection method.

[0031] Optionally, the switching of the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method includes:

[0032] Adjust the initial injection voltage value of the closed-loop current injection method to be consistent with the final injection voltage value of the open-loop voltage injection method, and clear the PI link error signal of the closed-loop current injection method.

[0033] In a second aspect, the present invention provides a harmonic injection device, including:

[0034] A first module, configured to determine the current rotational speed range in which the motor rotational speed is located, and determine the harmonic injection method according to the current rotational speed range;

[0035] A second module, configured to, when the motor rotational speed switches from the current rotational speed range to another rotational speed range, switch the harmonic injection method to match the other rotational speed range, wherein the final injection voltage value when switching out of the current rotational speed range is equal to the initial injection voltage value when switching to the other rotational speed range.

[0036] In a third aspect, the present invention provides an electronic device, including a memory and a processor;

[0037] The memory is used for storing a computer program;

[0038] The processor is configured to, when executing the computer program, implement the harmonic injection method as described in the first aspect.

[0039] In a fourth aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the harmonic injection method as described in the first aspect is implemented.

[0040] The beneficial effects of the harmonic injection method of the present invention are as follows: corresponding harmonic injection methods are determined according to different motor speeds. For example, the closed-loop current injection method is adopted at low and medium speeds, which has good adaptability to the batch production scatter (component differences) of the electric drive system, high current feedback control accuracy, stable injection effect, and excellent low-frequency noise suppression effect. For example, the open-loop voltage injection method is adopted at medium and high speeds, which is not limited by the current loop bandwidth, is applicable to the full speed range (low speed to high speed), and can ensure high-speed noise suppression ability. Corresponding harmonic injection methods are matched according to different application scenarios, enhancing the pertinence and avoiding the problem that a single fixed harmonic injection method cannot be applied to all application scenarios, thereby significantly improving the high-order harmonic noise suppression effect in multiple scenarios. In addition, when the harmonic injection method is switched, by ensuring that the injection voltage values before and after the switch are consistent, abnormal noises caused by motor voltage / current fluctuations are avoided, and thus the NVH performance of the electric drive system is effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic flow chart of the harmonic injection method according to an embodiment of the present invention;

[0042] Figure 2 It is a schematic flow chart of determining the harmonic injection method according to an embodiment of the present invention;

[0043] Figure 3 It is a schematic flow chart of the closed-loop current injection method according to an embodiment of the present invention;

[0044] Figure 4 It is a schematic flow chart of the open-loop voltage injection method according to an embodiment of the present invention;

[0045] Figure 5 It is a schematic flow chart of the harmonic injection method switch according to an embodiment of the present invention;

[0046] Figure 6 It is an execution schematic diagram of the closed-loop current injection method according to an embodiment of the present invention;

[0047] Figure 7 It is an execution schematic diagram of the open-loop voltage injection method according to an embodiment of the present invention;

[0048] Figure 8 It is a system architecture diagram of the harmonic injection device according to an embodiment of the present invention;

[0049] Figure 9 It is a system architecture diagram of the electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of specific embodiments of the present invention with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments described herein. Instead, these embodiments are provided to more thoroughly and completely understand the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not used to limit the protection scope of the present invention.

[0051] It should be understood that the various steps described in the method embodiments of the present invention can be executed in a different order and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this regard.

[0052] The term "including" and its variants used herein are open-ended, that is, "including but not limited to"; the term "based on" is "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules, or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules, or units.

[0053] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly stated in the context, it should be understood as "one or more".

[0054] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only for illustrative purposes and are not used to limit the scope of these messages or information.

[0055] As Figure 1 shown, a harmonic injection method provided by an embodiment of the present invention includes:

[0056] S100: Determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range.

[0057] Specifically, the harmonic injection methods include closed-loop current injection and open-loop voltage injection. For the closed-loop current injection method, the generally applicable speed range is low to medium speed (<5000 rpm), which has good adaptability to the batch production scatter of the electric drive system. However, limited by the current loop bandwidth, stable injection cannot be achieved at medium to high speeds. For the open-loop voltage injection method, the generally applicable speed range is medium to high speed (≥5000 rpm). Open-loop voltage injection is not restricted by speed and can be applied to medium to high speeds. However, its adaptability to the batch production scatter of the electric drive system is poor, and the injection effect in special working conditions is poor. Therefore, it is necessary to determine the appropriate harmonic injection method according to the current speed range in which the motor speed is located.

[0058] S200: When the motor speed switches from the current speed range to other speed ranges, switch the harmonic injection method to match the other speed ranges, where the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

[0059] Specifically, taking the current speed range as low to medium speed (<5000 rpm) as an example, the harmonic injection method at this time is the closed-loop current injection method. When the motor speed switches from low to medium speed (<5000 rpm) to medium to high speed (≥5000 rpm), switch the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method, and the final injection voltage value of the closed-loop current injection method is equal to the initial injection voltage value of the open-loop voltage injection method. Taking the current speed range as medium to high speed (≥5000 rpm) as an example, the harmonic injection method at this time is the open-loop voltage injection method. When the motor speed switches from medium to high speed (≥5000 rpm) to low to medium speed (<5000 rpm), switch the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method, and the final injection voltage value of the open-loop voltage injection method is equal to the initial injection voltage value of the closed-loop current injection method.

[0060] In this embodiment, the corresponding harmonic injection method is determined according to different motor speeds. For example, the closed-loop current injection method is adopted at low to medium speeds, which has good adaptability to the batch production scatter (component differences) of the electric drive system, high current feedback control accuracy, stable injection effect, and excellent low-frequency noise suppression effect. For example, the open-loop voltage injection method is adopted at medium to high speeds, which is not restricted by the current loop bandwidth and is applicable to the full speed range (low speed to high speed), and can ensure the high-speed noise suppression ability. Matching the corresponding harmonic injection method according to different application scenarios enhances the pertinence and avoids the problem that a single fixed harmonic injection method cannot be applied to all application scenarios, thereby significantly improving the high-order harmonic noise suppression effect in multiple scenarios. In addition, when the harmonic injection method is switched, by ensuring that the injection voltage values before and after the switch are consistent, abnormal noises caused by motor voltage / current fluctuations are avoided, and thus the NVH performance of the electric drive system is effectively guaranteed.

[0061] Optionally, the harmonic injection method includes a closed-loop current injection method and an open-loop voltage injection method. Determining the harmonic injection method according to the current speed range includes:

[0062] S110: When the current speed range is a speed range less than a preset threshold, execute the closed-loop current injection method.

[0063] Specifically, as shown in Figure 2 , taking the preset threshold as 5000 rpm as an example, if the current speed range is low to medium speed (<5000 rpm), then execute the closed-loop current injection method, detect the motor current signal in real time through the current control loop, and superimpose a compensating current harmonic at a specific frequency to cancel the non-linear characteristics of the motor.

[0064] S120: When the current speed range is a speed range greater than or equal to the preset threshold, execute the open-loop voltage injection method.

[0065] Specifically, as shown in Figure 2 , if the current speed range is medium to high speed (≥5000 rpm), then execute the open-loop voltage injection method, directly superimpose a harmonic voltage command at a specific frequency in the SVPWM modulation, without current feedback, and directly modulate the motor voltage.

[0066] In this optional embodiment, corresponding harmonic injection methods are determined for different motor speeds, that is, a combined scheme of low-speed closed-loop current injection + high-speed open-loop voltage injection is adopted, which can balance the suppression effect and batch production consistency, and ensure the high-speed noise suppression ability.

[0067] Optionally, executing the closed-loop current injection method includes:

[0068] S111: Determine the injection current amplitude and injection current phase according to the motor speed and motor torque.

[0069] Specifically, as shown in Figure 3 , determine the Nth injection current amplitude is and the Nth injection current phase θ according to the motor speed and motor torque.

[0070] Among them, the radial electromagnetic force fluctuation in the motor is the main source of whistling noise. The source of the radial force is the non-uniform distribution of the magnetic flux density in the motor air gap magnetic field. For motors with a specific slot-pole ratio, the order noise generated during one revolution is also specific, specifically including: (1) Stator slot harmonics, generated by the slot number effect + magnetomotive force distortion, affecting the 24th harmonic. The 24th-order NVH problem corresponds to the 5th and 7th harmonics in the three-phase stationary coordinate system; (2) PWM modulation harmonics, generated by the inverter SVPWM switching characteristics, affecting the 48th harmonic. The 48th harmonic vibration problem corresponds to the 11th and 13th harmonics in the three-phase stationary coordinate system.

[0071] S112: Determine the injection current components in the dq coordinate system according to the injection current amplitude and the injection current phase.

[0072] Specifically, as shown in Figure 3 , the Nth injection current phase θ is converted into orthogonal components sin(θ) and cos(θ) through sine and cosine functions, so that the injection voltage components in the dq coordinate system can be calculated, that is, the Nth harmonic iq injection value = is × sin(θ), and the Nth harmonic id injection value = is × cos(θ).

[0073] S113: Perform harmonic injection according to the injection current components.

[0074] Specifically, as shown in Figure 3 , perform harmonic injection according to the injection current components, that is, determine the comprehensive voltage signal to be loaded onto the motor, and load the comprehensive voltage signal onto the motor.

[0075] In this optional embodiment, by adopting the closed-loop current injection method at low and medium speeds (<5000 rpm), it has good adaptability to the batch production scatter (component differences) of the electric drive system, high current feedback control accuracy, stable injection effect, and excellent low-frequency noise suppression effect.

[0076] Optionally, the performing harmonic injection according to the injection current components includes:

[0077] Compare the injection current components with the feedback harmonic current, input the difference signal between the injection current components and the feedback harmonic current into a PI regulator to determine the high-order harmonic voltage signal; use the inverse Park transformation to convert the high-order harmonic voltage signal into harmonic voltage components, determine the comprehensive voltage signal to be loaded onto the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal onto the motor; wherein, the feedback harmonic current is determined by performing Park transformation on the fundamental current component based on the fundamental electrical angle.

[0078] Specifically, as shown in Figure 6As shown, based on the fundamental electrical angle, Park transformation is performed on the fundamental current components (id and iq) to determine the feedback harmonic current. The injection current component is compared with the feedback harmonic current, and the corresponding difference signal is input into a PI regulator to determine the high-order harmonic voltage signal. The inverse Park transformation is used to convert the high-order harmonic voltage signal into harmonic voltage components (ud_n and uq_n). The fundamental voltage components (ud and uq) are superimposed with the harmonic voltage components (ud_n and uq_n) to obtain the comprehensive voltage signal to be loaded onto the motor. Through the fundamental voltage limit and modulation module, the comprehensive voltage signal is limited and modulated to ensure that the output voltage does not exceed the inverter voltage range.

[0079] Among them, the fundamental electrical angle represents the electrical angle position of the rotation of the motor stator magnetic field. It is the synchronous reference angle of the motor rotor position, directly reflecting the position of the motor rotating magnetic field, and can be obtained through a position sensor (such as an encoder, resolver, etc.) or an observer (such as a PLL phase-locked loop); in the dq coordinate system, the fundamental electrical angle is used for Park transformation and inverse Park transformation to convert current and voltage signals in the three-phase stationary coordinate system to the rotating coordinate system, thereby simplifying the control.

[0080] Among them, the fundamental axis current (i.e., the fundamental current component) refers to the current component at the fundamental frequency, usually representing the projection of the motor stator current in the dq axis coordinate system. The d-axis current (id) and q-axis current (iq) can be converted from the three-phase stationary coordinate system through Park transformation.

[0081] Among them, the fundamental axis voltage (i.e., the fundamental voltage component) is the voltage component defined in the rotating coordinate system (dq coordinate system) in the motor control system, representing the projection of the motor stator voltage on the synchronous rotating coordinate system. The fundamental axis voltage (d-axis voltage ud and q-axis voltage uq) is usually converted from the voltage signal in the three-phase stationary coordinate system through Park transformation.

[0082] Among them, due to the different projections of the harmonic orders in the three-phase stationary coordinate system on the DQ axis, -6 and +6 times the fundamental electrical angle are used for the 5th and 7th harmonics, and -12 and +12 times the fundamental electrical angle are used for the 11th and 13th harmonics.

[0083] Among them, for the harmonic current PI parameters, they can also be determined by looking up a table according to the motor torque and speed. For example, the control parameters of the proportional-integral (PI) regulator in the harmonic current closed-loop control, the proportional gain (Kp) and the integral gain (Ki).

[0084] In this optional embodiment, harmonic injection is performed according to the injection current component, thereby realizing the closed-loop current injection method, which has good adaptability to the batch production scatter (component differences) of the electric drive system, high current feedback control accuracy, stable injection effect, and excellent low-frequency noise suppression effect.

[0085] Optionally, the implementation of the open-loop voltage injection method includes:

[0086] S121: Determine the injection voltage amplitude and injection voltage phase according to the motor speed and motor torque.

[0087] Specifically, in combination with Figure 4 as shown, determine the Nth injection voltage amplitude us and the Nth injection voltage phase θ according to the motor speed and motor torque.

[0088] S122: Determine the injection voltage components in the dq coordinate system according to the injection voltage amplitude and the injection voltage phase.

[0089] Specifically, in combination with Figure 4 as shown, convert the Nth injection voltage phase θ into orthogonal components sin(θ) and cos(θ) through sine and cosine functions, so that the injection voltage components in the dq coordinate system can be calculated, that is, the Nth harmonic uq injection value = us×sin(θ), and the Nth harmonic ud injection value = us×cos(θ).

[0090] S123: Perform harmonic injection according to the injection voltage components.

[0091] Specifically, in combination with Figure 4 and Figure 7 as shown, perform harmonic injection according to the injection voltage components, that is, determine the comprehensive voltage signal to be loaded to the motor, and load the comprehensive voltage signal to the motor.

[0092] In this optional embodiment, by adopting the open-loop voltage injection method at medium and high speeds (≥5000 rpm), it is not limited by the current loop bandwidth, is applicable to the full speed range (low speed to high speed), and can ensure the high-speed noise suppression ability.

[0093] Optionally, the performing harmonic injection according to the injection voltage components includes:

[0094] Based on the fundamental electrical angle, use the inverse Park transformation to convert the injection voltage components into harmonic voltage components, determine the comprehensive voltage signal to be loaded to the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal to the motor.

[0095] Specifically, in combination with Figure 7As shown, based on the fundamental electrical angle, the inverse Park transformation is performed on the injected voltage component to obtain the harmonic voltage components (ud_n and uq_n). The fundamental voltage components (ud and uq) are superimposed with the harmonic voltage components (ud_n and uq_n) to obtain the comprehensive voltage signal to be loaded onto the motor. Through the fundamental voltage limit and modulation module, the comprehensive voltage signal is limited and modulated to ensure that the output voltage does not exceed the inverter voltage range.

[0096] In this alternative embodiment, harmonic injection is performed according to the injected voltage component, thereby implementing an open-loop voltage injection method, which is not limited by the current loop bandwidth, is applicable to the full speed range (low speed to high speed), and can ensure high-speed noise suppression ability.

[0097] Optionally, when the motor speed switches from the current speed range to other speed ranges, switching the harmonic injection method to match the other speed ranges includes:

[0098] S210: When the motor speed switches from a speed range less than the preset threshold to a speed range greater than or equal to the preset threshold, switch the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method.

[0099] Specifically, as shown in Figure 5 When the motor speed accelerates from a speed range less than the preset threshold to a speed range greater than or equal to the preset threshold, the closed-loop current injection method is switched to the open-loop voltage injection method, and the open-loop injected voltage value remains the same as the injected voltage value at the moment of exiting the closed loop.

[0100] S220: When the motor speed switches from a speed range greater than or equal to the preset threshold to a speed range less than the preset threshold, switch the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method.

[0101] Specifically, as shown in Figure 5 When the motor speed decelerates from a speed range greater than or equal to the preset threshold to a speed range less than the preset threshold, the open-loop voltage injection method is switched to the closed-loop current injection method, and the closed-loop current injection voltage value remains the same as the injected voltage value at the moment of exiting the open loop.

[0102] In this alternative embodiment, by switching the harmonic injection method to match the speed range where the motor speed is located when the motor speed changes, the suppression effect and batch production consistency can be balanced, and the high-speed noise suppression ability can be ensured.

[0103] Optionally, switching the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method includes:

[0104] Adjust the initial injection voltage value of the open-loop voltage injection method to be consistent with the final injection voltage value of the closed-loop current injection method.

[0105] Specifically, when the motor speed accelerates from a speed range less than the preset threshold to a speed range greater than the preset threshold, the closed-loop current injection method is switched to the open-loop voltage injection method, and the open-loop injection voltage value is kept consistent with the injection voltage value at the moment of closed-loop exit.

[0106] In this alternative embodiment, by switching the harmonic injection method to the open-loop voltage injection method when the motor speed changes and keeping the injection voltage value consistent, abnormal noises caused by motor voltage / current fluctuations are avoided, thereby effectively ensuring the NVH performance of the electric drive system.

[0107] Optionally, the switching of the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method includes:

[0108] Adjust the initial injection voltage value of the closed-loop current injection method to be consistent with the final injection voltage value of the open-loop voltage injection method, and clear the PI link error signal of the closed-loop current injection method.

[0109] Specifically, since there is an output initial value in the closed-loop current injection, and this initial value usually has a large difference from the output final value at the moment of open-loop voltage injection exit. After direct switching, there will be current fluctuations and even NVH abnormal noises. Therefore, at the moment of open-loop voltage injection exit, a smooth transition is performed for switching to the closed-loop current injection: (1) The final values of open-loop Ud and Uq are given as the initial values of the closed-loop integral term, and the open-loop voltage final value is assigned to the initial value of the closed-loop integral term to ensure a smooth transition of the closed-loop control output voltage and the open-loop output voltage, and to avoid voltage mutations caused by the initial value of the integral term being 0, preventing dynamic impacts on the motor output; (2) Set the initial closed-loop PI link err to 0 to avoid a large voltage output by the PI controller at the moment of switching due to the non-zero initial error value, causing system fluctuations, and ensuring that the system maintains a stable state during the switching.

[0110] In this alternative embodiment, by performing a smooth transition when switching from the open-loop voltage injection method to the closed-loop current injection method, the motor runs smoothly during the system switching process, and at the same time, the dynamic response performance of the system is improved.

[0111] As Figure 8 shown, a harmonic injection device 800 provided by an embodiment of the present invention includes:

[0112] A first module 810, configured to determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range;

[0113] A second module 820, configured to switch the harmonic injection method to match the other speed range when the motor speed switches from the current speed range to the other speed range, wherein the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

[0114] As Figure 9 shown, an electronic device 900 provided by an embodiment of the present invention includes a memory 920 and a processor 910; the memory 920 is configured to store a computer program; the processor 910 is configured to implement the harmonic injection method as described above when executing the computer program.

[0115] Or, an electronic device 900 includes a memory 920 and a processor 910 coupled to the memory 920; the memory 920 is configured to store a computer program; the processor 910 is configured to perform the following operations when executing the computer program:

[0116] Determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range;

[0117] When the motor speed switches from the current speed range to the other speed range, switch the harmonic injection method to match the other speed range, wherein the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

[0118] A computer-readable storage medium provided by an embodiment of the present invention, on which a computer program is stored, and when the computer program is executed by a processor, the harmonic injection method as described above is implemented.

[0119] Or, a non-volatile computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the processor is caused to perform the following operations:

[0120] Determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range;

[0121] When the motor speed switches from the current speed range to the other speed range, switch the harmonic injection method to match the other speed range, wherein the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

[0122] Now, the electronic device 900 that can be a server or a client of the present invention will be described. It is an example of a hardware device that can be applied to various aspects of the present invention. The electronic device 900 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device 900 can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0123] The electronic device 900 includes a computing unit that can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) or a computer program loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The computing unit, ROM, and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0124] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above methods. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc. In the present application, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present invention. In addition, the functional units in various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0125] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the protection scope of the present invention.

Claims

1. A harmonic injection method, characterized in that, Including: Determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range; When the motor speed switches from the current speed range to other speed ranges, switch the harmonic injection method to match the other speed ranges, where the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

2. The harmonic injection method according to claim 1, wherein The harmonic injection method includes a closed-loop current injection method and an open-loop voltage injection method. The determining the harmonic injection method according to the current speed range includes: When the current speed range is a speed range less than a preset threshold, execute the closed-loop current injection method; When the current speed range is a speed range greater than or equal to the preset threshold, execute the open-loop voltage injection method.

3. The harmonic injection method according to claim 2, wherein The executing the closed-loop current injection method includes: Determine the injection current amplitude and injection current phase according to the motor speed and motor torque; Determine the injection current components in the dq coordinate system according to the injection current amplitude and the injection current phase; Perform harmonic injection according to the injection current components.

4. The harmonic injection method according to claim 3, characterized in that, The performing harmonic injection according to the injection current components includes: Compare the injection current components with the feedback harmonic current, and input the difference signal between the injection current components and the feedback harmonic current into a PI regulator to determine the high-order harmonic voltage signal; Use the inverse Park transformation to convert the high-order harmonic voltage signal into harmonic voltage components, determine the comprehensive voltage signal to be loaded to the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal to the motor; Wherein, the feedback harmonic current is determined by performing Park transformation on the fundamental current component based on the fundamental electrical angle.

5. The harmonic injection method according to claim 2, wherein The executing the open-loop voltage injection method includes: Determine the injection voltage amplitude and injection voltage phase according to the motor speed and motor torque; Determine the injection voltage components in the dq coordinate system according to the injection voltage amplitude and the injection voltage phase; Perform harmonic injection according to the injection voltage components.

6. The harmonic injection method according to claim 5, wherein The performing harmonic injection according to the injection voltage components includes: Based on the fundamental electrical angle, use the inverse Park transformation to convert the injection voltage components into harmonic voltage components, determine the comprehensive voltage signal to be loaded to the motor according to the harmonic voltage components and the fundamental voltage components, and load the comprehensive voltage signal to the motor.

7. The harmonic injection method according to claim 2, characterized in that, The when the motor speed switches from the current speed range to other speed ranges, switching the harmonic injection method to match the other speed ranges includes: When the motor speed switches from a speed range less than the preset threshold to a speed range greater than or equal to the preset threshold, switch the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method; When the motor speed switches from a speed range greater than or equal to the preset threshold to a speed range less than the preset threshold, switch the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method.

8. The harmonic injection method according to claim 7, characterized in that Said switching the harmonic injection method from the closed-loop current injection method to the open-loop voltage injection method includes: Adjusting the initial injection voltage value of the open-loop voltage injection method to be consistent with the final injection voltage value of the closed-loop current injection method.

9. The harmonic injection method according to claim 7, wherein Said switching the harmonic injection method from the open-loop voltage injection method to the closed-loop current injection method includes: Adjusting the initial injection voltage value of the closed-loop current injection method to be consistent with the final injection voltage value of the open-loop voltage injection method, and clearing the PI link error signal of the closed-loop current injection method.

10. A harmonic injection device, characterized in that, Includes: A first module, configured to determine the current speed range in which the motor speed is located, and determine the harmonic injection method according to the current speed range; A second module, configured to switch the harmonic injection method to match the other speed range when the motor speed switches from the current speed range to the other speed range, wherein the final injection voltage value when switching out of the current speed range is equal to the initial injection voltage value when switching to the other speed range.

11. An electronic device, characterized in that, Includes a memory and a processor; The memory is used to store a computer program; The processor is configured to implement the harmonic injection method according to any one of claims 1 to 9 when executing the computer program.

12. A computer-readable storage medium, characterized in that, A computer program is stored on the storage medium, and when the computer program is executed by a processor, the harmonic injection method according to any one of claims 1 to 9 is implemented.

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