CN116404941B - A motor control method, device and readable storage medium - Google Patents

Abstract

This application provides a motor control method, device and readable storage medium, relating to the technical field of motor control. The method includes: during the motor control process, N (N is 2 or 3) analog-to-digital converters are simultaneously triggered during the current switching cycle of the switching element to sample the current of the three-phase motor to obtain N current values. Within a switching cycle, the action of the switching element is controlled according to N current values to control the operation of the three-phase motor through the drive circuit. During the current sampling process, N analog-to-digital converters operate simultaneously, which can make the deviation between the sampling moments of the obtained current values of the three-phase current close to or equal to zero, so that the obtained current values can more accurately represent the three-phase current values. In this way, when controlling the operation of the three-phase motor according to the current value of the three-phase current, the three-phase motor can have higher stability.

Description

A motor control method, device and readable storage medium

Technical field

The present application relates to the field of motor control technology, and in particular to a motor control method, device and readable storage medium.

Background technique

At present, the three-phase motor control system mainly includes a controller, a drive circuit and a three-phase motor. The controller can sample the three-phase current of the three-phase motor to obtain the current value, and control the action of the switching element in the drive circuit based on the sampled current value to control the operation of the three-phase motor through the drive circuit.

In related technologies, during the process of sampling three-phase currents by the controller, there may be deviations between the sampling times of the three-phase currents. As a result, the sampled current values of the three-phase currents may not be the current values at the same time and cannot be accurate. Characterizes the status of the three-phase motor. In this way, when controlling the operation of the three-phase motor based on the sampled current value, the stability of the three-phase motor will be poor.

Contents of the invention

Embodiments of the present application provide a motor control method, device and readable storage medium, which can make the deviation between the sampling moments of the obtained current values of the three-phase current close to or equal to zero, which is beneficial to improving the stability of the three-phase motor. .

In a first aspect, a motor control method is provided, which method includes:

During the current switching cycle of the switching element, N analog-to-digital converters are simultaneously triggered to sample the current of the three-phase motor to obtain N current values. The switching element is located in the drive circuit of the three-phase motor. Each analog-to-digital converter Sampling one phase current of the three-phase motor respectively, and the N is 2 or 3;

In the next adjacent switching period, the action of the switching element is controlled according to the N current values to control the operation of the three-phase motor through the drive circuit.

In the embodiment of the present application, during the current sampling process, N analog-to-digital converters operate simultaneously, which can make the deviation between the sampling times of the obtained current values of the three-phase current close to or equal to zero, so that the obtained three-phase current can be The current value of the current can more accurately characterize the state of the three-phase motor, so that when controlling the operation of the three-phase motor based on the current value of the three-phase current, the three-phase motor can have higher stability.

At the same time, during the control process of the three-phase motor, there is no need to use an algorithm to reduce the time deviation between the current values of the three-phase currents sampled, which can reduce the calculation amount of the controller, thereby reducing the power consumption of the controller.

In some embodiments, triggering N analog-to-digital converters simultaneously to sample the current of the three-phase motor to obtain N current values includes: simultaneously triggering the N analog-to-digital converters to sample the three-phase motor at the first moment. The N current values are obtained from the current, and the first moment is located after the state switching moment of the switching element and is separated by a preset time length from the state switching moment.

In the embodiment of this application, after the state of the switching element is switched, N analog-to-digital converters are simultaneously triggered at a preset time interval to sample the current of the three-phase motor, and the current value of the three-phase motor when it reaches a stable state can be obtained. In this way, a current value that can accurately characterize the state of the motor is obtained, thereby improving the stability of the three-phase motor when controlling the operation of the three-phase motor based on the current value.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In the embodiment of the present application, the current of the three-phase motor is sampled at a preset time interval after the state of the switching element is switched for the first time. The analog-to-digital converter can be controlled to sample the current of the three-phase motor at the beginning of the switching cycle. Sampling can simplify the current sampling process.

In some embodiments, triggering the N analog-to-digital converters simultaneously at the first moment to sample the current of the three-phase motor to obtain the N current values includes: triggering the N analog-to-digital converters through a trigger wave The converter samples the current of the three-phase motor at the first moment to obtain the N current values, and the trigger wave is obtained by delaying the reference wave of the switching element for the preset time period.

In the embodiment of the present application, a trigger wave that can simultaneously trigger the action of N analog-to-digital converters is obtained by delaying the reference wave of the switching element. The N analog-to-digital converters are triggered by the trigger wave to simultaneously sample the current of the three-phase motor. The control process It is relatively simple and can control the sampling time more accurately, which can improve the accuracy of current sampling and thus improve the stability of the three-phase motor control process.

In some embodiments, the preset time period is greater than or equal to 30 microseconds.

Among them, when the preset time Δt is greater than or equal to 30 microseconds, N analog-to-digital converters can be used to sample the current of the three-phase motor after the three-phase motor enters a stable state, so that the current of the three-phase motor can be obtained. The current value in the steady state can improve the stability of the three-phase motor control process.

In some embodiments, the preset time period is less than or equal to 50 microseconds.

Among them, when the preset time Δt is less than or equal to 50 microseconds, N analog-to-digital converters can sample the current of the three-phase motor in time after the switching element switches state, which can improve the timeliness and accuracy of current sampling. effectiveness.

In some embodiments, the simultaneous triggering of N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values includes: simultaneously triggering the N analog-to-digital converters to sample at the state switching moment of the switching element. The current of the three-phase motor is used to obtain the N current values.

In the embodiment of the present application, N analog-to-digital converters are simultaneously triggered to sample the current of the three-phase motor at the moment when the switching element switches state, which can simplify the current sampling process.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In the embodiment of the present application, the current of the three-phase motor is sampled when the state of the switching element is switched for the first time. The analog-to-digital converter can be controlled to sample the current of the three-phase motor at the beginning of the switching cycle, which can simplify Current sampling process.

In some embodiments, simultaneously triggering the N analog-to-digital converters to sample the current of the three-phase motor at the moment of state switching of the switching element includes: simultaneously triggering the N analog-to-digital converters through the reference wave of the switching element. N analog-to-digital converters sample the current of the three-phase motor.

In the embodiment of the present application, N analog-to-digital converters are simultaneously triggered by the reference wave of the switching element to sample the current of the three-phase motor. The control process is relatively simple and can simplify the current sampling process.

In a second aspect, a motor control device is provided, which device includes:

The trigger module is used to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values during the current switching cycle of the switching element. The switching element is located in the drive circuit of the three-phase motor. Analog-to-digital converters respectively sample one phase current of the three-phase motor, and the N is 2 or 3;

A control module, configured to control the action of the switching element according to the N current values in the next adjacent switching cycle, so as to control the operation of the three-phase motor through the drive circuit.

In some embodiments, the triggering module is specifically configured to simultaneously trigger the N analog-to-digital converters to sample the current of the three-phase motor to obtain the N current values at the first moment. There is a preset time interval between the state switching moment of the switching element and the state switching moment.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In some embodiments, the trigger module is specifically configured to trigger the N analog-to-digital converters to sample the current of the three-phase motor at the first moment to obtain the N current values through a trigger wave. The wave is obtained by delaying the reference wave of the switching element by the preset time period.

In some embodiments, the preset time period is greater than or equal to 30 microseconds.

In some embodiments, the preset time period is less than or equal to 50 microseconds.

In some embodiments, the triggering module is specifically configured to simultaneously trigger the N analog-to-digital converters to sample the current of the three-phase motor at the moment of state switching of the switching element to obtain the N current values.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In some embodiments, the triggering module is specifically configured to simultaneously trigger the N analog-to-digital converters to sample the current of the three-phase motor through the reference wave of the switching element.

In a third aspect, a readable storage medium is provided. A computer program is stored on the readable storage medium. When the computer program is run on a motor control device, the motor control device causes the motor control device to execute the aforementioned first aspect. Provided motor control methods.

In a fourth aspect, a motor control device is provided, including: a processor; a memory; and a computer program, wherein the computer program is stored in the memory, and when the computer program is executed by the processor, the computer program causes the computer program to The motor control device executes the motor control method provided in the first aspect.

In a fifth aspect, a computer program product is provided, including: computer program code. When the computer program code is run on a motor control device, it causes the motor control device to execute the motor control method provided in the first aspect.

A sixth aspect provides a chip, including: a processor for calling and running a computer program from a memory, so that a motor control device installed with the chip executes the motor control method provided in the first aspect.

It can be understood that the motor control device provided by the second aspect and the fourth aspect, the readable storage medium provided by the third aspect, the computer program product provided by the fifth aspect, and the chip provided by the sixth aspect are all used to execute the aforementioned first aspect. The motor control method provided by the aspect, therefore, the beneficial effects it can achieve can be referred to the beneficial effects in the corresponding method provided above, and will not be described again here.

Description of the drawings

Figure 1 shows a schematic structural diagram of a motor control system in the related art.

FIG. 2 shows a timing diagram of a motor control system in the related art.

Figure 3 shows a step flow chart of a motor control method provided by an embodiment of the present application.

FIG. 4 shows a schematic structural diagram of a motor control system provided by an embodiment of the present application.

FIG. 5 shows a timing diagram of a motor control system provided by an embodiment of the present application.

Figure 6 shows a timing diagram of another motor control system provided by an embodiment of the present application.

FIG. 7 shows a timing diagram of another motor control system provided by an embodiment of the present application.

FIG. 8 shows a schematic structural diagram of another motor control system provided by an embodiment of the present application.

FIG. 9 shows a schematic structural diagram of a motor control device provided by an embodiment of the present application.

Figure 10 shows a structural block diagram of a motor control device provided by an embodiment of the present application.

Detailed ways

The technical solutions in this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments.

In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures and technologies are provided to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

The term "comprising" as used herein indicates the presence of described features, integers, steps, operations, elements and/or components but does not exclude the presence of one or more other features, integers, steps, operations, elements, components and/or collections thereof existence or addition. The terms “including,” “includes,” “having,” and variations thereof all mean “including but not limited to,” unless otherwise specifically emphasized. Hereinafter, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the embodiments of this application, unless otherwise specified, "plurality" means two or more.

The term "and/or" in this article is just an association relationship that describes related objects, indicating that three relationships can exist. For example, A and/or B can mean: A exists alone, A and B exist simultaneously, and they exist alone. B these three situations. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

Figure 1 shows a schematic structural diagram of a motor control system in the related art. As shown in Figure 1, the motor control system mainly includes a controller 11, a drive circuit 12 and a three-phase motor 13. The driving circuit 12 may be a three-phase bridge inverter circuit (also called an inverter), including a first bridge arm composed of a first switching element 121 and a second switching element 122, a third switching element 123 and a fourth switch. The second bridge arm is composed of the element 124, and the third bridge arm is composed of the fifth switching element 125 and the sixth switching element 126.

The switching elements include, but are not limited to, insulated gate bipolar transistors (IGBTs) and insulated gate field effect transistors (metal oxide semiconductors, MOSs). The first switching element 121 , the third switching element 123 , and the fifth switching element 125 can also be called the upper arm of the driving circuit 12 . One end of the upper arm is connected to the positive electrode of the DC power supply, and the other end is connected to the three-phase motor 13 . The second switching element 122 , the fourth switching element 124 and the sixth switching element 126 can also be called a lower bridge arm. One end of the lower bridge arm is connected to the negative pole of the DC power supply, and the other end is connected to the three-phase motor 13 .

The controller 11 may be a micro controller unit (MCU). The six output pins of the controller 11 are respectively connected to the control end of a corresponding switching element in the drive circuit 12 for outputting pulse widths to the six switching elements. Modulate (pulse width modulation, PWM) wave to control the switching element to be on or off. The PWM wave output by the controller 11 to the switching element can be called a control wave.

The controller 11 includes one or more analog to digital converters (analog to digital converters, ADC), which can sample analog signals to convert the analog signals into digital signals. The analog-to-digital converter usually includes multiple channels, each channel can be configured to correspond to an input pin of the controller 11, and an analog signal is sampled through the input pin corresponding to the channel.

In the related art, the three-phase currents of the three-phase motor 13 are mainly sampled through three channels of an analog-to-digital converter included in the controller 11 . As shown in Figure 1, the controller 11 includes a first analog-to-digital converter 111. The three channels of the first analog-to-digital converter 111 are configured as three input pins of the controller 11, and the three input pins are connected respectively. The three lower arms in the drive circuit 12. During the operation of the three-phase motor, the three channels of the first analog-to-digital converter 111 respectively sample one phase current of the three-phase motor 13, and three current values of the three-phase current can be sampled.

FIG. 2 shows a timing diagram of a motor control system in the related art. In Figure 2, the abscissa is time t, and the ordinate is voltage U. The first curve 21 , the second curve 22 and the third curve 23 are respectively the three-phase voltages of the three-phase motor 13 . During the control process of the three-phase motor, the controller 11 internally generates the reference wave 24 of the switching element. The reference wave 24 is a PWM wave. The reference wave 24 is used to trigger the six output pins to output control waves to the corresponding switching elements respectively. The first control wave 25 is the control wave of the lower bridge arm, and the second control wave 26 is the control wave of the upper bridge arm.

Among them, the switching element is in a conductive state during a high-level period corresponding to the control wave, and is in a cut-off state during a low-level period corresponding to the control wave, so that the reference wave 24 can control the switching element in the driving circuit 12 to be periodically turned on and off. . The period T of the reference wave 24 is the switching period of the switching element. In each switching period, the switching element is first turned on and then turned off or first turned off and then turned on.

At the same time, the controller 11 outputs the reference wave 24 to the first analog-to-digital converter 111. The rising edge of the reference wave 24 triggers the first analog-to-digital converter 111 to perform one sampling in each switching cycle, and the signal flowing through the lower bridge arm is The analog current is converted into a digital current value to realize the sampling of three-phase current.

Among them, due to the hardware reasons of the analog-to-digital converter, when the analog-to-digital converter is triggered to sample the three-phase current, multiple channels of the analog-to-digital converter perform current sampling at different times, so that each channel in the analog-to-digital converter There is a large time deviation between the sampling moments.

For example, when the controller 11 triggers the first analog-to-digital converter 111 to start sampling the three-phase current through the rising edge of the reference wave 24, the three channels of the first analog-to-digital converter 111 will respectively be at the first sampling time t1 ( The first sampling time is the starting time of the switching cycle), the second sampling time t2 and the third sampling time t3 sample the three-phase current, so that the three current values of the three-phase current sampled are not the current values at the same time. , there is a large time deviation between the sampling moments of the three current values, resulting in that the sampled current values of the three-phase current cannot accurately represent the state of the three-phase motor 13. In this way, the three-phase current values are controlled based on the current values of the three-phase currents. When the motor 13 is running, the stability of the three-phase motor 13 will be poor.

In order to solve the problem of inconsistent sampling times of three-phase currents, algorithms are usually used to correct the current values of the three-phase currents sampled to reduce the time deviation between the current values of the three-phase currents, so that the sampled three-phase currents are The current value of the current is as equal as possible to the current value sampled at the same time. However, the correction effect of the algorithm is poor, and the time deviation between the corrected current values of the three-phase current still exists, and the state of the three-phase motor cannot be accurately represented.

In order to solve the above technical problems, embodiments of the present application provide a motor control method. During the motor control process, N (N is 2 or 3) analog-to-digital converters are simultaneously triggered within the current switching cycle of the switching element to control the three-phase motor. The current is sampled. Each analog-to-digital converter samples one phase current of the three-phase motor 13, and can sample 3 current values of the three-phase current, or obtain 2 current values of the two-phase current through 2 Calculate the current value of the other phase current to obtain the current value of the other phase current. Then, in the next adjacent switching cycle, the switching element action is controlled according to the three current values of the three-phase current, and the three-phase motor operation is controlled through the drive circuit.

During the current sampling process, N analog-to-digital converters operate simultaneously, which can make the deviation between the sampling moments of the obtained current values of the three-phase current close to or equal to zero, so that the obtained current values of the three-phase current can be It can more accurately represent the status of the three-phase motor, so that the three-phase motor can have higher stability when controlling the operation of the three-phase motor according to the current value of the three-phase current.

Compared with the method of reducing the time deviation between the current values of the three-phase current through an algorithm, the time deviation between the sampled current values of the three-phase current can be accurately reduced. At the same time, during the control process of the three-phase motor, there is no need to use an algorithm to reduce the time deviation between the current values of the three-phase currents sampled, which can reduce the calculation amount of the controller, thereby reducing the power consumption of the controller.

Figure 3 shows a step flow chart of a motor control method provided by an embodiment of the present application. As shown in Figure 3, the method can be executed by the controller, including step 31 and step 32.

Step 31: During the current switching cycle of the switching element, trigger N analog-to-digital converters at the same time to sample the current of the three-phase motor to obtain N current values.

Among them, the switching element is located in the drive circuit of the three-phase motor, and each analog-to-digital converter samples one phase current of the three-phase motor, and N is 2 or 3.

FIG. 4 shows a schematic structural diagram of a motor control system provided by an embodiment of the present application. As shown in Figure 4, the controller 11 includes a first analog-to-digital converter 111, a second analog-to-digital converter 112 and a third analog-to-digital converter 113. The corresponding input pin of each analog-to-digital converter is connected to the driving circuit respectively. One of the lower bridge arms in 12.

In some embodiments, the controller 11 can simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor at the moment when the switching element switches state to obtain N current values. For example, during the motor control process, the controller 11 can output the reference wave 24 of the switching element to the analog-to-digital converter, and use the reference wave 24 to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor 13 .

FIG. 5 shows a timing diagram of a motor control system provided by an embodiment of the present application. As shown in Figure 5, the controller 11 internally generates a reference wave 24. The reference wave 24 triggers the level transitions of the three output pins corresponding to the second switching element 122, the fourth switching element 124 and the sixth switching element 126, generating The first control wave 25 and the reference wave 24 trigger the level transitions of the three output pins corresponding to the first switching element 121 , the third switching element 123 and the fifth switching element 125 to generate the second control wave 26 .

At the starting time t4 in the current switching period T1, the first control wave 25 jumps to a low level, which can turn off the second switching element 122, the fourth switching element 124 and the sixth switching element 126. At the same time, at the starting time t4, the second control wave 26 can turn on the first switching element 121, the third switching element 123 and the fifth switching element 125, so that the state of the switching elements in the driving circuit 12 is at the starting time t4. The first switch occurs.

At the intermediate time t5 in the current switching period T1, the first control wave 25 jumps to a high level, which can turn on the second switching element 122, the fourth switching element 124 and the sixth switching element 126. At the same time, the second control wave 26 jumps to a low level, which can turn off the first switching element 121, the third switching element 123 and the fifth switching element 125, so that the state of the switching elements in the driving circuit 12 occurs at the intermediate time t5. Second switch.

Similarly, in the next adjacent switching period T2, the first control wave 25 and the second control wave 26 repeat the above process, which can cause the state of the switching element to cycle on and off in each switching period, thereby realizing three-dimensional switching. Control of phase motor 13.

Among them, in the current switching period T1, the state of the switching element in the driving circuit 12 switches for the first time at the starting time t4, and the second switching occurs at the intermediate time t5. The starting time t4 and the intermediate time t5 can be called switches. The state switching time of the component.

In some embodiments, the analog-to-digital converter can be set to rising edge triggering, and the rising edge of the reference wave 24 can trigger the analog-to-digital converter to sample the current of the three-phase motor 13 . As shown in Figure 5, when the analog-to-digital converter is a rising edge trigger, after the reference wave 24 is input to the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113, it can be started At time t4, the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113 are simultaneously triggered to sample, hold, quantize, and encode the current of the connected lower arm to complete the three-phase current analysis. A sampling is performed to obtain the current value of each phase current.

Among them, when the rising edge of the reference wave 24 triggers the analog-to-digital converter to sample the current of the three-phase motor 13, N analog-to-digital converters can be triggered to sample the three-phase motor 13 at the same time when the state of the switching element is switched for the first time. 13 currents are sampled.

In the embodiment of the present application, N analog-to-digital converters are simultaneously triggered to sample the current of the three-phase motor at the moment when the switching element switches state, which can simplify the current sampling process. The current of the three-phase motor is sampled when the state of the switching element switches for the first time. The analog-to-digital converter can be controlled to sample the current of the three-phase motor at the beginning of the switching cycle, which can simplify the current sampling process.

In the embodiment of the present application, N analog-to-digital converters are simultaneously triggered by the reference wave of the switching element to sample the current of the three-phase motor. The control process is relatively simple and can simplify the current sampling process.

In other embodiments, the analog-to-digital converter may be set to fall-edge triggering, and the falling edge of the reference wave 24 may trigger the analog-to-digital converter to sample the current of the three-phase motor 13 . As shown in Figure 5, when the analog-to-digital converter is falling edge triggered, after the reference wave 24 is input to the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113, it can be t5 simultaneously triggers the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113 to sample, hold, quantize, and encode the current of the connected lower bridge arm to complete the analysis of the three-phase current. After one sampling, the current value of each phase current is obtained.

Among them, when the analog-to-digital converter is triggered by the falling edge of the reference wave 24 to sample the current of the three-phase motor 13, N analog-to-digital converters can be triggered to sample the current of the three-phase motor 13 when the state of the switching element is switched for the second time. The current is sampled.

In practical applications, the reference wave 24 can also be used to simultaneously trigger two analog-to-digital converters in the controller 11 at the starting time t4 or the intermediate time t5 to sample two of the three-phase currents to obtain the three-phase motor 13 2 current values of the two-phase current.

In this embodiment, in the process of simultaneously triggering N analog-to-digital converters to sample three-phase currents, when the analog-to-digital converters include multiple channels, the number of channels of the analog-to-digital converters corresponding to each phase current is the same. . For example, the second channel of the first analog-to-digital converter 111 can be used to sample the first phase current of the three-phase current, and the second channel of the second analog-to-digital converter 112 can be used to sample the second phase current of the three-phase current. The phase current is sampled, and the second channel of the third analog-to-digital converter 113 is used to sample the third phase current of the three-phase current.

Among them, N analog-to-digital converters use the same channel to sample the current, which can reduce the deviation between the sampling moments of different analog-to-digital converters, and can reduce the time deviation between the sampling moments of the sampled N current values. Improve the stability of three-phase motors.

It can be understood that the analog-to-digital converter can also have only one channel. When the analog-to-digital converter has only one channel, each analog-to-digital converter can directly sample one phase current of the three-phase motor.

Step 32: In the next adjacent switching cycle, control the action of the switching element according to the N current values to control the operation of the three-phase motor through the drive circuit.

In this embodiment, after the controller 11 samples and obtains the three current values of the three-phase current of the three-phase motor 13 in the current switching period T1, the controller 11 can adjust the reference wave 24 according to the three current values of the three-phase current. The duty cycle in the next switching cycle T2 can be adjusted by adjusting the duty cycle of the reference wave 24 to adjust the duty cycle of the 6 control waves in the next adjacent switching cycle T2, thereby adjusting the upper bridge in the driving circuit 12 The conduction time of the three-phase motor 13 can be controlled by the drive circuit 12 to control the operation of the three-phase motor 13 .

It can be understood that, after the controller 11 samples the current values of the two-phase currents of the three-phase motor 13 in the current switching period T1, it can calculate the current value of the other phase current based on the current values of the two-phase currents, thus obtaining Three current values of the three-phase current of the three-phase motor 13 in the current switching period T1.

As shown in Figure 3, the controller 11 can execute steps 31 and 32 cyclically, simultaneously triggering 2 or 3 analog-to-digital converters for current sampling in the current switching period T1, and obtain the three-phase current of the three-phase motor 13 in the current switching period T1. The current value of the phase current is obtained, and in the next adjacent switching period T2, the switching elements in the drive circuit 12 are controlled according to the obtained current value to control the operation of the three-phase motor 13. Specifically, the method of controlling the action of the switching element according to the current value of the three-phase current can be specifically set according to the requirements.

Optionally, the step of simultaneously triggering N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values may include:

At the first moment, N analog-to-digital converters are simultaneously triggered to sample the current of the three-phase motor to obtain N current values. The first moment is located after the state switching moment of the switching element and is separated by a preset time period from the state switching moment.

In some embodiments, the controller 11 can delay the reference wave of the switching element for a preset time to obtain a trigger wave, output the trigger wave to N analog-to-digital converters, and simultaneously trigger the N analog-to-digital converters at the first moment through the trigger wave. The current of the three-phase motor 13 is sampled to obtain N current values.

Figure 6 shows a timing diagram of another motor control system provided by an embodiment of the present application. As shown in FIG. 6 , after the controller 11 generates the reference wave 24 , while generating six control waves through the reference wave 24 , the controller 11 can delay the reference wave 24 by a preset time period Δt to generate the trigger wave 27 . The interval between the rising edge of the trigger wave 27 and the rising edge of the reference wave 24 is a preset time length Δt, and the interval between the jumping edge of the trigger wave 27 (including the rising edge and the falling edge) and the jumping edge of the reference wave 24 is a preset time length. Δt.

In some embodiments, the analog-to-digital converter can be set to rising edge triggering, and the rising edge of the trigger wave 27 can trigger the analog-to-digital converter to sample the current of the three-phase motor 13 . As shown in Figure 6, when the analog-to-digital converter is a rising edge trigger, after the trigger wave 27 is input to the first analog-to-digital converter 111, the second analog-to-digital converter 112 and the third analog-to-digital converter 113, the trigger wave 27 can be At time t6, the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113 are simultaneously triggered to sample, hold, quantize, and encode the current of the connected lower bridge arm to complete the three-phase current A sampling is performed to obtain the current value of each phase current.

Among them, when the analog-to-digital converter is triggered by the rising edge of the trigger wave 27 to sample the current of the three-phase motor 13, the first time t6 is located after the starting time t4, and is separated by a preset time period Δ from the starting time t4. t, N analog-to-digital converters can be triggered to sample the current of the three-phase motor 13 at the first time t6 after the first switching of the state of the switching element.

FIG. 7 shows a timing diagram of another motor control system provided by an embodiment of the present application. As shown in FIG. 7 , the analog-to-digital converter can be set to fall edge triggering, and the falling edge of the trigger wave 27 can trigger the analog-to-digital converter to sample the current of the three-phase motor 13 . As shown in Figure 7, when the analog-to-digital converter is a falling edge trigger, after the trigger wave 27 is input to the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113, the trigger wave 27 can be At time t6, the first analog-to-digital converter 111, the second analog-to-digital converter 112, and the third analog-to-digital converter 113 are simultaneously triggered to sample, hold, quantize, and encode the current of the connected lower bridge arm to complete the three-phase current A sampling is performed to obtain the current value of each phase current.

Among them, when the analog-to-digital converter is triggered by the falling edge of the trigger wave 27 to sample the current of the three-phase motor 13, the first time t6 is located after the intermediate time t5 and is separated by a preset time period Δt from the intermediate time t5. N analog-to-digital converters can be triggered to sample the current of the three-phase motor 13 at the first time t6 after the second switching of the state of the switching element.

In practical applications, when the state of the switching element is just switched, the state of the three-phase motor 13 is not stable. The accuracy of the current value of the three-phase current obtained at this time is low. The three-phase motor is controlled according to the current value at this time. When 13 is running, the stability of the three-phase motor 13 is low. The preset time length Δt can be adjusted according to actual needs, so that after the three-phase motor 13 reaches stability, the analog-to-digital converter is triggered to sample and obtain the current value of the three-phase motor 13 .

In the embodiment of this application, after the state of the switching element is switched, N analog-to-digital converters are simultaneously triggered at a preset time interval to sample the current of the three-phase motor, and the current value of the three-phase motor when it reaches a stable state can be obtained. In this way, a current value that can accurately characterize the state of the motor is obtained, thereby improving the stability of the three-phase motor when controlling the operation of the three-phase motor based on the current value.

Among them, the current of the three-phase motor is sampled at a preset time interval after the state of the switching element is switched for the first time. The analog-to-digital converter can be controlled to sample the current of the three-phase motor at the beginning of the switching cycle, which can simplify Current sampling process.

In the embodiment of the present application, a trigger wave that can simultaneously trigger the action of N analog-to-digital converters is obtained by delaying the reference wave of the switching element. The N analog-to-digital converters are triggered by the trigger wave to simultaneously sample the current of the three-phase motor. The control process It is relatively simple and can control the sampling time more accurately, which can improve the accuracy of current sampling and thus improve the stability of the three-phase motor control process.

In some embodiments, the preset time period Δt is greater than or equal to 30 microseconds (μs). For example, the preset time period Δt can be 30 microseconds, 32 microseconds, 35 microseconds, 40 microseconds, 45 microseconds, 48 microseconds, etc., but is not limited thereto.

Among them, when the preset time Δt is greater than or equal to 30 microseconds, N analog-to-digital converters can be used to sample the current of the three-phase motor after the three-phase motor enters a stable state, so that the current of the three-phase motor can be obtained. The current value in the steady state can improve the stability of the three-phase motor control process.

In some embodiments, the preset time period Δt is less than or equal to 50 microseconds (μs). For example, the preset time period Δt can be 50 microseconds, 48 microseconds, 45 microseconds, 40 microseconds, etc., but is not limited thereto.

Among them, when the preset time Δt is less than or equal to 50 microseconds, N analog-to-digital converters can sample the current of the three-phase motor in time after the switching element switches state, which can improve the timeliness and accuracy of current sampling. effectiveness.

FIG. 8 shows a schematic structural diagram of another motor control system provided by an embodiment of the present application. As shown in FIG. 8 , the motor control system may also include a fourth analog-to-digital converter 14 , a fifth analog-to-digital converter 15 , and a sixth analog-to-digital converter 16 provided outside the controller 11 .

Among them, one output pin of the controller 11 is connected to the trigger end of the fourth analog-to-digital converter 14 for outputting the reference wave 24 or the trigger wave 27 to the fourth analog-to-digital converter 14, and one input pin of the controller 11 is connected to the trigger terminal of the fourth analog-to-digital converter 14. The communication end of the fourth analog-to-digital converter 14 is connected and used to obtain the current value sampled by the fourth analog-to-digital converter 14 . Similarly, the trigger terminal and the communication terminal of the fifth analog-to-digital converter 15 and the sixth analog-to-digital converter 16 are respectively connected to the controller 11 .

During the process of sampling the current of the three-phase motor 13 , after generating the reference wave 24 , the controller 11 may send signals to the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 15 and the sixth analog-to-digital converter 15 located outside the controller 11 . The trigger end of the analog-to-digital converter 16 outputs the reference wave 24 at the same time to simultaneously trigger the fourth analog-to-digital converter 14, the fifth analog-to-digital converter 15, and the sixth analog-to-digital converter 16 to sample the three-phase current to obtain three current value. After outputting the reference wave 24 , the controller 11 may receive signals from the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 14 , and the sixth analog-to-digital converter 16 through the communication terminals of the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 15 , and the sixth analog-to-digital converter 16 . The digital converter 15 and the sixth analog-to-digital converter 16 read the sampled current value.

Alternatively, during the process of sampling the current of the three-phase motor 13 , after generating the delayed reference wave 24 to obtain the trigger wave 27 , the controller 11 may send signals to the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 15 and the third analog-to-digital converter 15 . The triggering ends of the six analog-to-digital converters 16 simultaneously output the trigger wave 27 to simultaneously trigger the fourth analog-to-digital converter 14, the fifth analog-to-digital converter 15, and the sixth analog-to-digital converter 16 to conduct the three-phase current processing at the first moment. Sampling, get 3 current values. After outputting the trigger wave 27 , the controller 11 can receive signals from the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 14 , and the sixth analog-to-digital converter 16 through the communication terminals of the fourth analog-to-digital converter 14 , the fifth analog-to-digital converter 15 , and the sixth analog-to-digital converter 16 . The digital converter 15 and the sixth analog-to-digital converter 16 read the sampled current value.

FIG. 9 shows a schematic structural diagram of a motor control device provided by an embodiment of the present application. As shown in FIG. 9 , the motor control device 9 includes a trigger module 91 and a control module 92 .

The trigger module 91 is used to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values during the current switching cycle of the switching element. The switching element is located in the drive circuit of the three-phase motor, and each analog-to-digital converter is The converter samples one phase current of the three-phase motor respectively, and N is 2 or 3;

The control module 92 is used to control the action of the switching element according to the N current values in the next adjacent switching cycle to control the operation of the three-phase motor through the drive circuit.

In some embodiments, the trigger module 91 is specifically configured to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values at the first moment, which is located after the state switching moment of the switching element and is the same as the state switching moment of the switching element. There is a preset time interval between status switching moments.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In some embodiments, the trigger module 91 is specifically configured to trigger N analog-to-digital converters through a trigger wave to sample the current of the three-phase motor at the first moment to obtain N current values. The trigger wave is delayed by the reference wave of the switching element for a preset period of time. get later.

In some embodiments, the preset time period is greater than or equal to 30 microseconds.

In some embodiments, the preset time period is less than or equal to 50 microseconds.

In some embodiments, the trigger module 91 is specifically configured to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor at the moment when the switching element switches state, so as to obtain N current values.

In some embodiments, the state switching moment is the moment when the state of the switching element switches for the first time in the current switching cycle.

In some embodiments, the trigger module 91 is specifically configured to simultaneously trigger N analog-to-digital converters to sample the current of the three-phase motor through the reference wave of the switching element.

Figure 10 shows a structural block diagram of a motor control device provided by an embodiment of the present application. As shown in FIG. 10 , the motor control device 10 includes a processor 101 and a memory 102 , and each of the above devices can be connected through one or more buses 104 .

The motor control device 10 also includes a computer program 103. The computer program 103 is stored in the memory 102. When the computer program 103 is executed by the processor 101, the motor control device 10 is caused to execute the motor control method shown in FIG. 3 above. All relevant content of each step involved in the above method embodiments can be quoted from the functional description of the corresponding physical device, and will not be described again here.

Embodiments of the present application also provide a readable storage medium, which includes a computer program that, when run on a computer, causes the computer to execute the method provided by the above method embodiment.

Embodiments of the present application also provide a computer program product containing instructions, which when the computer program product is run on a computer, causes the computer to execute the method provided by the above method embodiment.

Embodiments of the present application also provide a chip system, including a memory and a processor. The memory is used to store a computer program. The processor is used to call and run the computer program from the memory, so that the motor control device installed with the chip system executes The method provided by the above method embodiment.

The chip system may include an input circuit or interface for sending information or data, and an output circuit or interface for receiving information or data.

It should be understood that in the embodiments of the present application, the processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits ( application specific integrated circuit (ASIC), ready-made field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

It should also be understood that the memory in the embodiments of the present application may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Among them, non-volatile memory can be read-only memory (ROM), programmable ROM (PROM), erasable programmable read-only memory (erasable PROM, EPROM), electrically removable memory. Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory. Volatile memory may be random access memory (RAM), which acts as an external cache. By way of illustration, but not limitation, many forms of random access memory (RAM) are available, such as static random access memory (static RAM, SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory Access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (synchlink DRAM, SLDRAM) and direct memory bus random access memory (direct rambus RAM, DR RAM).

Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be described again here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the coupling or direct coupling or communication connection between each other shown or discussed may be through some interfaces, and the indirect coupling or communication connection of the devices or units may be in electrical, mechanical or other forms.

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 may be located in one place, or they may be 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 this embodiment.

In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, each unit can exist physically alone, or two or more units can be integrated into one unit.

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the existing technology or the part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program code. .

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application. should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims (11)

1. A method of controlling an electric motor, the method comprising:

in the current switching period of a switching element, triggering N analog-to-digital converters to sample the current of a three-phase motor to obtain N current values, wherein the switching element is positioned in a driving circuit of the three-phase motor, each analog-to-digital converter is provided with a plurality of channels, each analog-to-digital converter samples one phase current of the three-phase motor through channels with the same channel number, and N is 2 or 3;

and in the next adjacent switching period, controlling the switching element to act according to the N current values so as to control the three-phase motor to operate through the driving circuit.

2. The method of claim 1, wherein simultaneously triggering the N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values comprises:

And triggering the N analog-to-digital converters to sample the current of the three-phase motor at the first moment to obtain the N current values, wherein the first moment is positioned after the state switching moment of the switching element and is spaced from the state switching moment by a preset time length.

3. The method of claim 2, wherein the state switching time is a time at which switching of the state of the switching element occurs for the first time in the current switching cycle.

4. The method of claim 2, wherein simultaneously triggering the N analog-to-digital converters to sample the current of the three-phase motor at the first time to obtain the N current values comprises:

and triggering the N analog-to-digital converters to sample the current of the three-phase motor at the first time through a trigger wave to obtain the N current values, wherein the trigger wave is obtained after the reference wave of the switching element delays for the preset time length.

5. The method of claim 2, wherein the predetermined time period is greater than or equal to 30 microseconds.

6. The method of any one of claims 2-5, wherein the preset duration is less than or equal to 50 microseconds.

7. The method of claim 1, wherein simultaneously triggering the N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values comprises:

And triggering the N analog-digital converters to sample the current of the three-phase motor at the state switching moment of the switching element so as to obtain the N current values.

8. The method of claim 7, wherein the state switching time is a time at which switching of the state of the switching element occurs for the first time in the current switching cycle.

9. The method according to claim 7 or 8, wherein simultaneously triggering the N analog-to-digital converters to sample the current of the three-phase motor at a state switching instant of the switching element comprises:

and the N analog-digital converters are triggered simultaneously by the reference wave of the switching element to sample the current of the three-phase motor.

10. A motor control device, the device comprising:

the triggering module is used for triggering N analog-to-digital converters to sample the current of the three-phase motor to obtain N current values in the current switching period of the switching element, the switching element is positioned in a driving circuit of the three-phase motor, each analog-to-digital converter is provided with a plurality of channels, each analog-to-digital converter samples one phase of current of the three-phase motor through channels with the same channel number, and N is 2 or 3;

And the control module is used for controlling the switching element to act according to the N current values in the next adjacent switching period so as to control the three-phase motor to run through the driving circuit.

11. A readable storage medium, characterized in that the readable storage medium has stored thereon a computer program which, when run on a motor control device, causes the motor control device to perform the method according to any of claims 1-9.