A motor control method and device, computer equipment and storage medium

Abstract

This invention provides a motor control method, apparatus, computer equipment, and storage medium. The method includes: when the motor controller restores power, obtaining the current phase value, current rotation direction, and speed of the target motor by detecting the differential line voltage signal of the two phases of the target motor; filtering and rectifying the differential signal to obtain a square wave signal; determining the frequency value of the square wave signal and determining the current speed of the target motor based on the frequency value of the square wave signal; generating a control signal based on the current speed, current rotation direction, and current phase value, and using the control signal to control the target motor to accelerate and start. The motor control method, apparatus, computer equipment, and storage medium provided by this invention can process the differential signal to obtain a square wave signal, and achieve direct acceleration and start of the target motor based on the current phase value, current rotation direction, and speed determined by the square wave signal, saving significant time and resources.

Description

Technical Field

[0001] This invention relates to the field of motor control, and specifically to a motor control method, device, computer equipment, and storage medium. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) are widely used in various fields due to their excellent performance, such as small size, high efficiency, high reliability, and strong environmental adaptability. A PMSM consists of a stator, rotor, and end covers. The stator is made of laminated laminations, and the rotor is equipped with permanent magnet material.

[0003] In existing technologies, conventional permanent magnet synchronous motor controllers do not have speed sensors. When the motor controller suddenly loses power and then regains power, it needs to wait for the rotating machinery to come to a complete stop before it can resume operation. However, waiting for the rotating machinery to come to a complete stop wastes a significant amount of time and resources. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem that the existing technology requires waiting for the rotating machinery to come to a standstill before it can continue to start working, which leads to a waste of a lot of time and resources, and thus provides a motor control method, device, computer equipment and storage medium.

[0005] According to a first aspect, the present invention provides a motor control method, the method comprising:

[0006] When the motor controller restores power, it obtains the current phase value, current rotation direction and speed of the target motor by detecting the differential line voltage signal between the two phases of the target motor.

[0007] The differential signal is filtered and rectified to obtain a square wave signal;

[0008] Determine the frequency value of the square wave signal, and determine the current speed of the target motor based on the frequency value of the square wave signal;

[0009] A control signal is generated based on the current rotation speed, the current rotation direction, and the current phase value, and the target motor is accelerated and started using the control signal.

[0010] In one embodiment, detecting the differential line voltage signal between two phases of the target motor includes:

[0011] The back electromotive force (EMF) signals of each phase stator coil of the target motor are obtained separately, and the differential signal of the back EMF of any two phase stator coils is calculated.

[0012] Determine the phase value of the differential signal of the back electromotive force of any two phase stator coils;

[0013] Differential signals whose phase values ​​meet preset conditions are selected as differential signals of the back electromotive force of the two-phase stator coils of the target motor. The preset conditions are that the phase values ​​are integer multiples of π.

[0014] In one embodiment, the method further includes:

[0015] The square wave signal is isolated to obtain an inverted square wave signal;

[0016] The square wave signal is updated using the inverted square wave signal.

[0017] In one embodiment, determining the frequency value of the square wave signal and determining the current speed of the target motor based on the frequency value of the square wave signal includes:

[0018] The time interval between adjacent rising edges or adjacent falling edges in the square wave signal is determined as the period of the square wave signal.

[0019] Based on the linear relationship between the cycle and the preset cycle and the rotational speed, the current rotational speed of the target motor is determined.

[0020] In one embodiment, after controlling the target motor to accelerate and start, the method further includes:

[0021] Obtain the real-time speed of the target motor;

[0022] Determine whether the real-time rotational speed is greater than a preset rotational speed threshold;

[0023] If the real-time speed is greater than the preset speed threshold, then the target motor is controlled to run based on the real-time speed.

[0024] According to a second aspect, the present invention provides a motor control device, the device comprising:

[0025] The acquisition module is used to detect the differential line voltage signal between the two phases of the target motor when the motor controller restores power, and to acquire the current phase value, current rotation direction and speed of the target motor.

[0026] The module is used to filter and rectify the differential signal to obtain a square wave signal;

[0027] The determining module is used to determine the frequency value of the square wave signal and determine the current speed of the target motor based on the frequency value of the square wave signal;

[0028] The control module is used to generate a control signal based on the current rotation speed, the current rotation direction, and the current phase value, and to use the control signal to control the target motor to accelerate and start.

[0029] According to a third aspect, the present invention provides a motor control device, the device comprising: a differential circuit, a signal processing circuit, and a controller, wherein...

[0030] The input terminal of the differential circuit is connected to the stator coils of each phase of the motor, and the output terminal is connected to the input terminal of the signal processing circuit. It is used to determine the differential signal of the back electromotive force of any two phase stator coils based on the back electromotive force signal of each phase stator coil of the motor.

[0031] The signal processing circuit includes an operational amplifier and a comparator, the output of which is connected to the input of the controller, and is used to filter and rectify the differential signal to obtain a square wave signal.

[0032] The controller is used to determine the frequency value of the square wave signal, and based on the frequency value of the square wave signal, determine the current speed of the target motor, generate a control signal based on the current speed, current rotation direction and current phase value, and use the control signal to control the target motor to accelerate and start.

[0033] In one embodiment, the differential circuit includes a resistor-capacitor coupling circuit, wherein,

[0034] The two input terminals of the RC coupling circuit are respectively connected to the two-phase stator coils of the target motor, and the two output terminals are respectively connected to the positive input terminal and the negative input terminal of the operational amplifier.

[0035] In one embodiment, the device further includes an optocoupler, the input of which is connected to the output of the signal processing circuit and the output of which is connected to the input of the controller, for isolating the square wave signal output by the signal processing circuit to obtain an inverted square wave signal.

[0036] According to a fourth aspect, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the method provided in the first aspect and any alternative embodiment of the first aspect.

[0037] The technical solution of this invention has the following advantages:

[0038] This invention provides a motor control method that, when the motor controller is powered on, detects the differential signal of the back electromotive force of the two-phase stator coils of the target motor, processes the differential signal to obtain a square wave signal, determines the current speed of the target motor based on the square wave signal, and controls the target motor to restart based on the current phase value, current rotation direction, and current speed when the target motor is powered on again. Thus, without relying on external speed sensors and sensorless algorithms, the target motor speed can be detected, and there is no need to wait for the rotating machinery to come to a standstill. Instead, the target motor can be accelerated and started at the current speed, achieving direct acceleration and start-up of the target motor under dynamic conditions, saving a lot of time and resources. Attached Figure Description

[0039] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0040] Figure 1 This is a flowchart of a motor control method proposed in an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram illustrating the change in motor speed over time during power-off start-up in an embodiment of the present invention;

[0042] Figure 3 This is a signal processing circuit diagram in an embodiment of the present invention;

[0043] Figure 4 This is a structural block diagram of a motor control device proposed in an embodiment of the present invention;

[0044] Figure 5 This is a schematic diagram of the hardware structure of a computer device proposed in an embodiment of the present invention. Detailed Implementation

[0045] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Currently, when a typical sensorless permanent magnet synchronous motor controller is powered on, the motor rotor is in a non-stationary state of inertial rotation. Because no speed sensor is installed and the algorithm cannot detect its rotational speed and rotor position, the motor cannot start. This causes a significant delay when the controller suddenly cuts off and re-energizes certain rotating machinery driven by the motor at high speeds, waiting for the machinery to come to a complete stop before it can start operating, wasting considerable time and resources. This is especially true for molecular pumps in the vacuum field, where resistance is very low and rotational speeds reach tens of thousands of revolutions per minute. The time from this state to automatic shutdown can be very long, sometimes tens of minutes or even hours.

[0047] To reduce the time wasted waiting for rotating machinery to come to a standstill, this invention provides a motor control method, such as... Figure 1 As shown, the method includes the following steps S101 to S104.

[0048] Step S101: When the motor controller restores power, the current phase value, current rotation direction and target speed of the target motor are obtained by detecting the differential line voltage signal between the two phases of the target motor.

[0049] In this embodiment of the invention, a motor controller is installed inside the target motor. When the motor controller is powered on, it detects the differential line voltage signal between the two phases of the target motor. An inductive switch is pre-installed at the shaft of the target motor. The inductive switch transmits the sensing signal to the PLC (Programmable Logic Controller) to determine the current phase value, current rotation direction, and speed of the target motor. The current rotation direction of the target motor includes both clockwise and counterclockwise rotation directions.

[0050] The rotor of a permanent magnet synchronous motor is a permanent magnet, and its magnetic flux is sinusoidally distributed in space. The uniform rotation of the rotor causes the magnetic flux through the stator coil to change periodically with a sinusoidal pattern. The stator coil can induce a back electromotive force, which changes sinusoidally. By performing differential calculation on the back electromotive force, the differential signal of the back electromotive force of the two-phase stator coil of the target motor can be obtained.

[0051] Step S102: Filter and rectify the differential signal to obtain a square wave signal.

[0052] In this embodiment of the invention, the square wave is composed of a series of sine waves. The differential signal is processed by a low-pass filter to filter out sine waves with frequencies lower than a preset value, thus obtaining a square wave signal. The differential signal can also be filtered and rectified, or it can be input into a square wave conversion chip for processing. The use of a square wave conversion chip to convert a sinusoidal differential signal into a square wave is existing technology and will not be elaborated upon here.

[0053] Step S103: Determine the frequency value of the square wave signal, and determine the current speed of the target motor based on the frequency value of the square wave signal.

[0054] In this embodiment of the invention, the frequency and speed of the motor are linearly related. Based on the waveform of the square wave signal, the frequency value of the square wave signal is determined. According to the predetermined linear relationship, the current speed of the target motor is determined based on the frequency value of the square wave signal.

[0055] Step S104: Generate a control signal based on the current rotation speed, current rotation direction and current phase value, and use the control signal to control the target motor to accelerate and start.

[0056] In this embodiment of the invention, after obtaining the current rotational speed and current phase value, the current rotational speed and current phase value are directly input into the FOC (Field-Oriented Control), enabling control of the target motor based on the current rotational speed and current phase value. Controlling the target motor can be achieved by jointly determining the control signal based on the current rotational speed, current rotational direction, and current phase value, and then transmitting the control signal to the PLC to control the target motor. This allows for rapid start-up of the target motor under any operating condition, reducing the time spent waiting for the rotating machinery to stop.

[0057] Through the above embodiments, when the motor controller is powered on, the differential signal of the back electromotive force of the two-phase stator coils of the target motor can be detected. The differential signal is processed to obtain a square wave signal, and the current speed of the target motor can be determined based on the square wave signal. When the target motor is powered back on, the target motor can be restarted based on the current phase value, current rotation direction, and current speed. Thus, the target motor speed can be detected without relying on external speed sensors and sensorless algorithms. Instead of waiting for the rotating machinery to come to a standstill, it can be accelerated and started at the current speed, realizing direct acceleration and start-up of the target motor under dynamic conditions, saving a lot of time and resources.

[0058] Specifically, in one embodiment, the detection of the line voltage differential signal between the two phases of the target motor in step S101 includes the following steps:

[0059] Step S1011: Obtain the back electromotive force signals of each phase stator coil of the target motor, and calculate the differential signal of the back electromotive force of any two phase stator coils.

[0060] Step S1012: Determine the phase value of the differential signal of the back electromotive force of any two phase stator coils.

[0061] Step S1013: Select differential signals whose phase values ​​meet the preset conditions as differential signals of the back electromotive force of the two-phase stator coils of the target motor. The preset condition is that the phase value is an integer multiple of π.

[0062] In this embodiment of the invention, the three-phase motor has three-phase terminals: U, V, and W.

[0063] When the motor rotor rotates counterclockwise, the opposite electromotive forces are as follows:

[0064] Eu = KWcos(Wt)

[0065]

[0066]

[0067] When the motor rotor rotates clockwise, the opposite electromotive forces are shown below:

[0068] Eu = KWcos(Wt)

[0069]

[0070]

[0071] Where E is the back electromotive force, K is the motor back electromotive force constant, W is the rotor electric angular velocity, and t is the time starting from zero.

[0072] Because the magnitude and phase of the back electromotive force (EMF) have a linear relationship with the rotor's speed and position, but its dynamic range varies greatly and it generates significant interference noise, directly using the stator's back EMF is difficult. However, using the difference between the back EMFs of any two phase stator coils is relatively easy. By filtering, shaping, and pulse-transforming the differential waveform, the rotor's speed and position can be easily calculated. Therefore, the differential signals of the back EMFs of any two phase stator coils are calculated separately when the motor rotor rotates counterclockwise and clockwise:

[0073] When the motor rotor rotates counterclockwise

[0074]

[0075] Ev-Ew=-1.732KWSin(Wt-π)=1.732KWSin(Wt) (3)

[0076]

[0077] The phase values ​​of each differential signal are determined when the motor rotor rotates counterclockwise, respectively. 0、

[0078] When the motor rotor rotates clockwise

[0079]

[0080] Ev-Ew=1.732KWSin(Wt+π) (4)

[0081]

[0082] The phase values ​​of each differential signal are determined when the motor rotor rotates clockwise, respectively. π and

[0083] In this embodiment of the invention, differential signals with phase values ​​that are integer multiples of π are easy to calculate, so the differential signals are filtered based on their phase values. Since the phase values ​​of the differential signals of phases VW are 0 and π when the motor rotor rotates clockwise and counterclockwise, respectively, the differential signals of phases VW are filtered and used as the differential signals of the back electromotive force of the two-phase stator coils of the target motor. The differential signals of phases VW are taken, low-pass filtered, and compared with the zero-crossing point to obtain a square wave signal with a duty cycle of 50% and an angular frequency of W. This signal is input to the CPU pulse input hardware of the motor, and its frequency can be obtained. The rotor phase value at the moment the pulse occurs is either 0 or π.

[0084] Specifically, in one embodiment, the motor control method provided by this embodiment further includes the following steps:

[0085] Step S105: Isolate the square wave signal to obtain an inverted square wave signal.

[0086] Step S106: Update the square wave signal using the inverted square wave signal.

[0087] In this embodiment of the invention, the square wave signal can be isolated using an optocoupler isolator and an isolation chip. The optocoupler isolator, being unidirectional, ensures complete electrical isolation between the input and output terminals. The inverted square wave signal obtained after isolation is used to update the square wave signal, reducing interference from other signals and enhancing the stability of the square wave signal.

[0088] Specifically, in one embodiment, determining the frequency value of the square wave signal and determining the current speed of the target motor based on the frequency value of the square wave signal in step S103 includes the following steps:

[0089] Step S1031: Determine the time interval between adjacent rising edges or adjacent falling edges in the square wave signal as the period of the square wave signal.

[0090] Step S1032: Determine the current speed of the target motor based on the linear relationship between the period and the preset period and the speed.

[0091] In this embodiment of the invention, the time interval between adjacent rising edges or adjacent falling edges of a square wave signal can be acquired using a timer, or the period of the square wave signal can be acquired using an STM32 chip. Acquiring the period of the square wave signal using a timer or an STM32 chip is prior art and will not be elaborated upon here. Based on the period of the square wave signal, the reciprocal of the period is used to obtain the frequency of the square wave signal.

[0092] Calculate the current speed of the target motor using the following formula:

[0093]

[0094] Where n is the motor speed, f is the frequency, and p is the number of pole pairs of the motor's rotating magnetic field. Calculating the speed based on the period is existing technology and will not be elaborated upon here.

[0095] Specifically, in one embodiment, after performing the above step S104, the motor control method provided by this embodiment further includes the following steps:

[0096] Step S107: Obtain the real-time speed of the target motor.

[0097] Step S108: Determine whether the real-time rotational speed is greater than the preset rotational speed threshold.

[0098] Step S109: If the real-time speed is greater than the preset speed threshold, then control the target motor to run based on the real-time speed.

[0099] In this embodiment of the invention, after the target motor is restarted, a speed test is performed on the target motor to obtain its real-time rotational speed. It is then determined whether the real-time rotational speed is greater than a preset speed threshold. This preset speed threshold can be the minimum speed at which the target motor can operate normally, or it can be set according to the speed requirements of the actual application scenario of the target motor; no limitation is made here. Performing a speed test on the restarted target motor facilitates real-time monitoring of its rotational speed, allowing operators to adjust the target motor when its speed is too high or too low, thus reducing the possibility of malfunctions.

[0100] like Figure 2 As shown, Figure 2 This diagram illustrates the change in target motor speed over time after four power outages and restarts following the application of the aforementioned motor control method. It shows that the target motor does not need to wait for the rotating machinery to come to a complete stop before restarting, thereby increasing the starting efficiency of the target motor and reducing the waste of time and resources.

[0101] The present invention also provides a motor control device, such as... Figure 3 As shown, it includes: differential circuit 1, signal processing circuit 2, and controller (not shown in the figure), wherein,

[0102] The input terminals of differential circuit 1 are connected to the stator coils of each phase of the target motor. Figure 3 In this circuit, Motor represents the target motor. The output of differential circuit 1 is connected to the input of signal processing circuit 2. It is used to determine the differential signal of the back electromotive force of any two phase stator coils based on the back electromotive force signals of each phase stator coil of the target motor.

[0103] The signal processing circuit 2 includes an operational amplifier and a comparator. The output of the signal processing circuit 2 is connected to the input of the controller and is used to filter and rectify the differential signal to obtain a square wave signal.

[0104] The controller determines the frequency value of the square wave signal and, based on that frequency, determines the current speed of the target motor. It then generates a control signal based on the current speed, current direction of rotation, and current phase value, and uses this control signal to accelerate the target motor during startup. The specific execution process of the controller is described in the relevant descriptions of the above method embodiments, and will not be repeated here.

[0105] Specifically, the differential circuit 1 includes a resistor-capacitor (RC) coupling circuit, wherein the two input terminals of the RC coupling circuit are respectively connected to two phase stator coils of the target motor, and the two output terminals are respectively connected to the positive input terminal and the negative input terminal of the operational amplifier. The RC coupling circuit includes multiple coupling capacitors to couple the differential signal of the back electromotive force of any two phase stator coils of the target motor to the positive input terminal and the negative input terminal of the operational amplifier.

[0106] In one embodiment, the motor control device further includes an optocoupler U28. The input terminal of the optocoupler U28 is connected to the output terminal of the signal processing circuit 2, and is used to isolate the optical wave signal output by the signal processing circuit 2 to obtain an inverted square wave signal UOUTIN. The output terminal of the optocoupler U28 is connected to the input terminal of the controller. The optocoupler U28 enables complete electrical isolation between the input and output signals, allowing the inverted square wave signal obtained after isolation to update the square wave signal, thereby reducing interference from other signals and enhancing the stability of the square wave signal.

[0107] In this embodiment of the invention, when there is no PWM voltage superposition on the phase lines of the target motor, the differential signal of the back electromotive force of any two phases of the stator coil of the target motor is acquired. For example, the sinusoidal differential signal between the phase lines V and W of the target motor is input to the positive and negative input terminals of operational amplifier IC6B via a differential circuit. After low-pass filtering by operational amplifier IC6B, a sinusoidal signal with a positive bias of 2.5V is output from pin 1 of operational amplifier IC6B. This signal is then compared with the 2.5V voltage output by IC7B via comparator IC7A, generating a square wave signal with a duty cycle of 50% and a frequency consistent with the rotor back electromotive force at pin 7 of comparator IC7A. The square wave signal is filtered and rectified, then passed through optocoupler U28 to obtain an inverted square wave signal. This inverted signal is used to update the square wave signal, which is then transmitted to the relevant CPU hardware pins of the target motor for processing to calculate the rotor speed of the target motor.

[0108] The motor control device provided in this invention can detect the differential signal of the back electromotive force of the two-phase stator coils of the target motor when the motor controller is powered on, process the differential signal to obtain a square wave signal, determine the current speed of the target motor based on the square wave signal, and control the target motor to restart based on the current phase value, current rotation direction and current speed when the target motor is powered on again. Thus, without relying on external speed sensors and sensorless algorithms, the target motor speed can be detected, and there is no need to wait for the rotating machinery to come to a standstill. Instead, it can accelerate and start at the current speed, realizing direct acceleration and start-up of the target motor under dynamic conditions, saving a lot of time and resources.

[0109] Based on the same inventive concept, the present invention also provides a motor control device.

[0110] Figure 4 This is a structural block diagram of a motor control device according to an exemplary embodiment. For example... Figure 4 As shown, the device includes:

[0111] The acquisition module 101 is used to acquire the current phase value, current rotation direction, and speed of the target motor when the motor controller restores power. For details, please refer to the relevant description of step S101 above, which will not be repeated here.

[0112] Module 102 is obtained, which is used to filter and rectify the differential signal to obtain a square wave signal. For details, please refer to the relevant description of step S102 above, which will not be repeated here.

[0113] The determining module 103 is used to determine the frequency value of the square wave signal and determine the current speed of the target motor based on the frequency value of the square wave signal. For details, please refer to the relevant description of step S103 above, which will not be repeated here.

[0114] The control module 104 is used to generate a control signal based on the current rotation speed, current rotation direction, and current phase value, and to control the target motor to accelerate and start using the control signal. For details, please refer to the relevant description of step S104 above, which will not be repeated here.

[0115] The motor control device provided in this invention can detect the differential signal of the back electromotive force of the two-phase stator coils of the target motor when the motor controller is powered on, process the differential signal to obtain a square wave signal, determine the current speed of the target motor based on the square wave signal, and control the target motor to restart based on the current phase value, current rotation direction and current speed when the target motor is powered on again. Thus, without relying on external speed sensors and sensorless algorithms, the target motor speed can be detected, and there is no need to wait for the rotating machinery to come to a standstill. Instead, it can accelerate and start at the current speed, realizing direct acceleration and start-up of the target motor under dynamic conditions, saving a lot of time and resources.

[0116] The specific limitations and beneficial effects of the aforementioned motor control device can be found in the limitations of the motor control method described above, and will not be repeated here. Each of the above modules can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the corresponding operations of each module.

[0117] Figure 5 This is a schematic diagram of the hardware structure of a computer device according to an exemplary embodiment. For example... Figure 5 As shown, the device includes one or more processors 1310 and a memory 1320, the memory 1320 including persistent memory, volatile memory, and a hard disk. Figure 5 Taking a processor 1310 as an example, the device may also include an input device 1330 and an output device 1340.

[0118] The processor 1310, memory 1320, input device 1330, and output device 1340 can be connected via a bus or other means. Figure 5 Taking the example of a connection between China and Israel via a bus.

[0119] Processor 1310 can be a Central Processing Unit (CPU). Processor 1310 can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations thereof. The general-purpose processor can be a microprocessor or any conventional processor.

[0120] The memory 1320, as a non-transitory computer-readable storage medium, includes persistent memory, volatile memory, and a hard disk. It can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the business management method in this embodiment. The processor 1310 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions, and modules stored in the memory 1320, thereby implementing any of the above-mentioned motor control methods.

[0121] The memory 1320 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data that is needed and required. Furthermore, the memory 1320 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 1320 may optionally include memory remotely located relative to the processor 1310, and these remote memories may be connected to the data processing device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0122] Input device 1330 can receive input digital or character information, and generate key signal inputs related to user settings and function control. Output device 1340 may include display devices such as a display screen.

[0123] One or more modules are stored in memory 1320, and when executed by one or more processors 1310, they perform actions such as... Figure 1 The motor control method shown.

[0124] The above-described product can execute the method provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in [reference 1]. Figure 1 The relevant descriptions in the illustrated embodiments.

[0125] This invention also provides a non-transitory computer storage medium storing computer-executable instructions that can execute the methods described in any of the above method embodiments. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0126] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A motor control method, characterized in that, The method includes: When the motor controller restores power, it obtains the current phase value, current rotation direction and speed of the target motor by detecting the differential line voltage signal between the two phases of the target motor. The differential signal is filtered and rectified to obtain a square wave signal; Determine the frequency value of the square wave signal, and determine the current speed of the target motor based on the frequency value of the square wave signal; A control signal is generated based on the current rotation speed, the current rotation direction, and the current phase value, and the target motor is accelerated and started using the control signal. The detection of the differential line voltage signal between the two phases of the target motor includes: The back electromotive force (EMF) signals of each phase stator coil of the target motor are obtained separately, and the differential signal of the back EMF of any two phase stator coils is calculated. Determine the phase value of the differential signal of the back electromotive force of any two phase stator coils; Differential signals whose phase values ​​satisfy a preset condition are selected as the differential signals of the back electromotive force of the two-phase stator coils of the target motor. The preset condition is that the phase value is... Integer multiples of; The three-phase motor has three-phase terminals: U, V, and W. The differential signals of the back electromotive force of any two phase stator coils are calculated when the motor rotor rotates counterclockwise and clockwise, respectively. When the motor rotor rotates counterclockwise, the opposite electromotive forces are shown in the following formula: When the motor rotor rotates clockwise, the opposite electromotive forces are as follows: in, E It is the back electromotive force. K Let be the back electromotive force constant of the motor. W Let t be the rotor's electric angular velocity, and t be the time starting from zero.

2. The method according to claim 1, characterized in that, The method further includes: The square wave signal is isolated to obtain an inverted square wave signal; The square wave signal is updated using the inverted square wave signal.

3. The method according to claim 1 or 2, characterized in that, Determining the frequency value of the square wave signal and determining the current speed of the target motor based on the frequency value of the square wave signal includes: The time interval between adjacent rising edges or adjacent falling edges in the square wave signal is determined as the period of the square wave signal. Based on the linear relationship between the cycle and the preset cycle and the rotational speed, the current rotational speed of the target motor is determined.

4. The method according to claim 1, characterized in that, After controlling the target motor to accelerate and start, the method further includes: Obtain the real-time speed of the target motor; Determine whether the real-time rotational speed is greater than a preset rotational speed threshold; If the real-time speed is greater than the preset speed threshold, then the target motor is controlled to run based on the real-time speed.

5. A motor control device, characterized in that, The device includes: The acquisition module is used to acquire the current phase value, current rotation direction and speed of the target motor by detecting the differential line voltage signal between the two phases of the target motor when the motor controller restores power. The module is used to filter and rectify the differential signal to obtain a square wave signal; The determining module is used to determine the frequency value of the square wave signal and determine the current speed of the target motor based on the frequency value of the square wave signal; The control module is used to generate a control signal based on the current rotation speed, the current rotation direction and the current phase value, and use the control signal to control the target motor to accelerate and start. Specifically, the acquisition module is used to: acquire the back electromotive force (EMF) signals of each phase stator coil of the target motor, and calculate the differential signal of the back EMF of any two phase stator coils; determine the phase value of the differential signal of the back EMF of the arbitrary two phase stator coils; and select the differential signal whose phase value meets a preset condition as the differential signal of the back EMF of the two phase stator coils of the target motor, wherein the preset condition is that the phase value is... Integer multiples of; The three-phase motor has three-phase terminals: U, V, and W. The differential signals of the back electromotive force of any two phase stator coils are calculated when the motor rotor rotates counterclockwise and clockwise, respectively. When the motor rotor rotates counterclockwise, the opposite electromotive forces are shown in the following formula: When the motor rotor rotates clockwise, the opposite electromotive forces are as follows: in, E It is the back electromotive force. K Let be the back electromotive force constant of the motor. W Let t be the rotor's electric angular velocity, and t be the time starting from zero.

6. A motor control device, characterized in that, include: Differential circuits, signal processing circuits, and controllers, among which, The input terminal of the differential circuit is connected to the stator coils of each phase of the motor, and the output terminal is connected to the input terminal of the signal processing circuit. It is used to determine the differential signal of the back electromotive force of any two phase stator coils based on the back electromotive force signal of each phase stator coil of the motor. The signal processing circuit includes an operational amplifier and a comparator, the output of which is connected to the input of the controller, and is used to filter and rectify the differential signal to obtain a square wave signal. The controller is used to determine the frequency value of the square wave signal, and based on the frequency value of the square wave signal, determine the current speed of the target motor, generate a control signal based on the current speed, current rotation direction and current phase value, and use the control signal to control the target motor to accelerate and start. Specifically, the differential circuit is used to: acquire the back electromotive force (EMF) signals of each phase stator coil of the target motor, and calculate the differential signal of the back EMF of any two phase stator coils; determine the phase value of the differential signal of the back EMF of the arbitrary two phase stator coils; and select the differential signal whose phase value satisfies a preset condition as the differential signal of the back EMF of the two phase stator coils of the target motor, wherein the preset condition is that the phase value is... Integer multiples of; The three-phase motor has three-phase terminals: U, V, and W. The differential signals of the back electromotive force of any two phase stator coils are calculated when the motor rotor rotates counterclockwise and clockwise, respectively. When the motor rotor rotates counterclockwise, the opposite electromotive forces are shown in the following formula: When the motor rotor rotates clockwise, the opposite electromotive forces are as follows: in, E It is the back electromotive force. K Let be the back electromotive force constant of the motor. W Let t be the rotor's electric angular velocity, and t be the time starting from zero.

7. The device according to claim 6, characterized in that, The differential circuit includes a resistor-capacitor coupling circuit, wherein... The two input terminals of the RC coupling circuit are respectively connected to the two-phase stator coils of the target motor, and the two output terminals are respectively connected to the positive input terminal and the negative input terminal of the operational amplifier.

8. The device according to claim 6, characterized in that, It also includes an optocoupler isolator, the input of which is connected to the output of the signal processing circuit and the output of which is connected to the input of the controller, for isolating the square wave signal output by the signal processing circuit to obtain an inverted square wave signal.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method as described in any one of claims 1-4.

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