Motor driver control method and device and motor driver

Abstract

The invention relates to the technical field of rotating speed control, in particular to a control method and device of a motor driver and the motor driver. The method comprises the following steps: determining a first rotating speed and a second rotating speed; whether the estimated rotating speed is smaller than a first rotating speed or not is judged every other preset time, and if yes, the estimated rotating speed is determined through high-frequency signal injection; if not, if the estimated rotating speed is smaller than or equal to the second rotating speed, a first electrical angle and a second electrical angle are determined, and an angle difference value is calculated; executing different schemes according to the comparison condition of the angle difference value and 0; if the angle difference value is greater than 0, determining an estimated rotating speed according to the first electrical angle; if the angle difference value is less than 0, determining an estimated rotating speed through a second sliding-mode observer; if the angle difference is equal to 0, determining an estimated rotating speed according to the second electrical angle; and if the estimated rotating speed is greater than the second rotating speed, determining the estimated rotating speed through the first sliding-mode observer. According to the invention, the problem of inaccurate estimation result in the switching process is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of speed control, in particular to a control method and device of a motor driver and the motor driver. BACKGROUND

[0002] The motor driver is a core device for controlling the operation of a motor, which realizes the speed, direction and torque control of the motor by adjusting voltage, current and signal. The core function of the motor driver is to convert the power of the power supply into mechanical energy of the motor and accurately adjust the speed of the motor according to the control instruction.

[0003] At present, the motor driver drives the motor in the following way: when the motor is at low speed, the high-frequency injection method is used to calculate the rotor angle to control the speed of the motor; when the motor is at high speed, the sliding mode observer method is used to calculate the rotor angle to control the speed of the motor.

[0004] When the high-frequency injection method and the sliding mode observer method are switched, a fixed coefficient weighted average algorithm is currently used to obtain a comprehensive rotor angle, and then the speed is obtained according to the comprehensive rotor angle. At this time, since the rotor angles obtained by the two methods are both error, the comprehensive rotor angle is uncontrollable, so there is a problem of inaccurate estimation result in the switching process. SUMMARY

[0005] Therefore, it is necessary to provide a control method and device of a motor driver and the motor driver to solve the above problems.

[0006] The embodiment of the present application is implemented in the following way: a control method of a motor driver, the control method of the motor driver comprising: determining a first speed and a second speed according to a target speed; every other preset time, determining whether the estimated speed is less than the first speed, if yes, determining the estimated speed by high-frequency signal injection; if the estimated speed is greater than or equal to the first speed, determining whether the estimated speed is greater than the second speed, if no, determining a first electrical angle by high-frequency signal injection and determining a second electrical angle by a first sliding mode observer, and calculating an angle difference between the first electrical angle and the second electrical angle; executing different schemes according to the comparison between the angle difference and 0: if the angle difference is greater than 0, determining the estimated speed according to the first electrical angle; if the angle difference is less than 0, determining the estimated speed by a second sliding mode observer; if the angle difference is equal to 0, determining the estimated speed according to the second electrical angle; if the estimated speed is greater than the second speed, determining the estimated speed by the first sliding mode observer.

[0007] In one of the embodiments, the application provides a control device of a motor driver, which comprises: a rotation speed determination module for determining a first rotation speed and a second rotation speed according to a target rotation speed; a first control module for determining whether the estimated rotation speed is less than the first rotation speed every other preset time, and if yes, determining the estimated rotation speed through high-frequency signal injection; a difference calculation module for determining whether the estimated rotation speed is greater than the second rotation speed if the estimated rotation speed is greater than or equal to the first rotation speed, and if no, determining a first electrical angle through high-frequency signal injection, determining a second electrical angle through the first sliding mode observer, and calculating an angle difference between the first electrical angle and the second electrical angle; a second control module for executing different schemes according to the comparison between the angle difference and 0: if the angle difference is greater than 0, determining the estimated rotation speed according to the first electrical angle; a third control module for determining the estimated rotation speed through the second sliding mode observer if the angle difference is less than 0; a fourth control module for determining the estimated rotation speed according to the second electrical angle if the angle difference is equal to 0; a fifth control module for determining the estimated rotation speed through the first sliding mode observer if the estimated rotation speed is greater than the second rotation speed.

[0008] In one of the embodiments, the application provides a motor driver, which comprises a control module, a power conversion module, and a detection module. The control module is used to execute the steps of the above-mentioned control method of the motor driver. The power conversion module is connected with the control module, and is used to perform power control on the motor according to the control module. The detection module is connected with the control module, and is used to monitor the real-time current and real-time voltage of the motor.

[0009] The control method of the motor driver provided by the embodiment of the application determines the first rotating speed and the second rotating speed according to the target rotating speed; every other preset time, it is judged whether the estimated rotating speed is less than the first rotating speed, if yes, the estimated rotating speed is determined through high-frequency signal injection; if the estimated rotating speed is greater than or equal to the first rotating speed, it is judged whether the estimated rotating speed is greater than the second rotating speed, if no, the first electric angle is determined through high-frequency signal injection, the second electric angle is determined through the first sliding mode observer, and the angle difference between the first electric angle and the second electric angle is calculated; different schemes are executed according to the comparison between the angle difference and 0: if the angle difference is greater than 0, the estimated rotating speed is determined according to the first electric angle; if the angle difference is less than 0, the estimated rotating speed is determined through the second sliding mode observer; if the angle difference is equal to 0, the estimated rotating speed is determined according to the second electric angle; if the estimated rotating speed is greater than the second rotating speed, the estimated rotating speed is determined through the first sliding mode observer. In this way, in the process of switching between the high-frequency injection and the sliding mode observer, that is, in the interval between the first rotating speed and the second rotating speed, every other preset time, the estimated rotating speed is determined in different ways according to the angle difference between the first electric angle and the second electric angle, until the angle difference is equal to 0 and the estimated rotating speed is determined through the first sliding mode observer, each time only one way is selected to determine the estimated rotating speed and the trend is close to 0, thus solving the problem of inaccurate estimation result in the switching process. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 A flow chart of the control method of the motor driver in one embodiment; Figure 2 A structural block diagram of the control device of the motor driver in one embodiment; Figure 3 A structural block diagram of the motor driver in one embodiment; Figure 4 An internal structural block diagram of the control module in one embodiment. DETAILED DESCRIPTION

[0011] In order to make the objectives, technical solutions and advantages of the application clearer, the application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application.

[0012] It can be understood that the terms "first", "second", and the like used herein can be used to describe various elements, but unless specifically stated, these elements are not limited by these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of the application, the first xx script can be referred to as the second xx script, and similarly, the second xx script can be referred to as the first xx script.

[0013] As Figure 1 shown in FIG. 1, in one embodiment, a control method of a motor driver is proposed, which can specifically include the following steps: S101, determining a first speed and a second speed according to a target speed; S102, every other preset time, judging whether the estimated speed is less than the first speed, if yes, determining the estimated speed through high-frequency signal injection; S103, if the estimated speed is greater than or equal to the first speed, judging whether the estimated speed is greater than the second speed, if no, determining the first electrical angle through high-frequency signal injection, determining the second electrical angle through the first sliding mode observer, and calculating the angle difference between the first electrical angle and the second electrical angle; S104, according to the comparison between the angle difference and 0, executing different schemes: if the angle difference is greater than 0, determining the estimated speed according to the first electrical angle; S105, if the angle difference is less than 0, determining the estimated speed through the second sliding mode observer; S106, if the angle difference is equal to 0, determining the estimated speed according to the second electrical angle; S107, if the estimated speed is greater than the second speed, determining the estimated speed through the first sliding mode observer.

[0014] In this embodiment, the target speed is related to the gear selected by the user, and each gear corresponds to a corresponding target speed.

[0015] In this embodiment, the preset time is the interval time for calculating the estimated speed, which can be set to 100 microseconds.

[0016] In this embodiment, the initial value of the estimated speed is 0, and each subsequent determination of the estimated speed is an update of the previous estimated speed.

[0017] In this embodiment, in the process of the estimated speed being greater than or equal to the first speed and less than the second speed, the three schemes in the comparison between the angle difference and 0 can all appear and will be re-judged every other preset time, and the target is that the angle difference is equal to 0 and tends to be stable, so as to gradually transition to determining the estimated speed through the first sliding mode observer.

[0018] In this embodiment, the high-frequency signal injection and the first sliding mode observer are both conventional methods, and correspond to low speed and high speed respectively as the way to calculate the estimated speed.

[0019] In this embodiment, the difference between the second sliding mode observer and the first sliding mode observer is that the gain K of the output is a dynamic variable that tends to decrease.

[0020] In this embodiment, the steps of determining the first electrical angle by injecting a high-frequency signal and then determining the estimated rotational speed by injecting the first electrical angle are the same as those of determining the estimated rotational speed by injecting a high-frequency signal.

[0021] In this embodiment, the steps of determining the second electrical angle through the first sliding mode observer and then determining the estimated rotational speed through the second electrical angle are the same as the steps of determining the estimated rotational speed through the first sliding mode observer.

[0022] This invention provides a motor driver control method that determines a first speed and a second speed based on a target speed. At preset time intervals, it checks whether the estimated speed is less than the first speed. If so, the estimated speed is determined by injecting a high-frequency signal. If the estimated speed is greater than or equal to the first speed, it checks whether the estimated speed is greater than the second speed. If not, a first electrical angle is determined by injecting a high-frequency signal, and a second electrical angle is determined by a first sliding mode observer. The angle difference between the first and second electrical angles is calculated. Different schemes are executed based on the comparison between the angle difference and 0: if the angle difference is greater than 0, the estimated speed is determined based on the first electrical angle; if the angle difference is less than 0, the estimated speed is determined by the second sliding mode observer; if the angle difference is equal to 0, the estimated speed is determined based on the second electrical angle; if the estimated speed is greater than the second speed, the estimated speed is determined by the first sliding mode observer. By doing so, during the switching between high-frequency injection and sliding mode observer modes, i.e. within the range of the first and second speeds, at preset intervals, different methods are selected to determine the estimated speed based on the angle difference between the first and second electrical angles, until the angle difference equals 0 and the method of determining the estimated speed through the first sliding mode observer is stably switched. Only one method is selected each time to determine the estimated speed, and the trend is closer to the angle difference being 0, which solves the problem of inaccurate estimation results during the switching process.

[0023] In one embodiment, determining the first speed and the second speed based on the target speed includes: Depend on Obtain the first rotational speed; Depend on The second rotational speed was obtained; in, The target rotational speed is given by 'a', which is the first preset ratio and 'b', where 'a' is less than 'b'.

[0024] In this embodiment, 'a' can be set to any value between 2% and 5%, and 'b' can be set to any value between 8% and 15%.

[0025] In one embodiment, determining the estimated rotational speed via high-frequency signal injection includes: Inject a high-frequency voltage signal into the motor and use a bandpass filter to extract the high-frequency current response; determining an error signal according to the high-frequency current response; inputting the error signal into a proportional integral observer to obtain a first electrical angle; determining an estimated speed according to a change amount of the first electrical angle.

[0026] In the embodiment, the high-frequency signal injection has multiple ways, such as rotating injection and pulsating injection.

[0027] In the embodiment, the estimated speed is determined according to a change amount of the first electrical angle, which is generally a difference between the latest two first electrical angles divided by a preset time.

[0028] In one embodiment, the second electrical angle is determined by the first sliding mode observer, comprising: obtaining real-time current and real-time voltage; establishing a first current observer model; inputting the real-time current and the real-time current into the first current observer model to obtain a first estimated current; obtaining a first error current according to the first estimated current and the real-time current; determining a first correction value according to the real-time current and the first estimated current; obtaining a first estimated back electromotive force according to the first correction value, the first error current and a switching function; obtaining the second electrical angle according to the first estimated back electromotive force.

[0029] In the embodiment, the estimated back electromotive force, the electrical angle and the speed can be obtained by the sliding mode observer algorithm. The three monitored currents are transformed into and and by clark transformation, and the voltages are the same. and are further transformed into and and by Park transformation, and the voltages are the same. and facilitate the tracking of two parallel PI controllers. , , and The electrical angle and the speed are obtained by the sliding mode observer algorithm, and the estimated back electromotive force is an intermediate calculation.

[0030] In the embodiment, since a low-pass filter is used to obtain the estimated back electromotive force, the amplitude of the estimated back electromotive force will be attenuated and the phase will be lagged, and the phase compensation of the estimated angle is needed, and in order to eliminate the influence of chattering on the sliding mode observer, the winding resistance is set to Set the winding inductance to The relationship between the estimated current and the input quantity can be set as follows: in, , for Estimating current in a coordinate system , To estimate the back electromotive force, , for Real-time voltage in the coordinate system This is a correction value. In the initial estimation, the estimated current on the right side of the equation can be set to the actual current, and the estimated back electromotive force can be set to 0. This yields the estimated current on the left side of the equation. Sliding mode itself gradually converges within the error. Since the constructed error equation is convergent, it will gradually move closer to the sliding surface, and the error will gradually decrease. In other words, the speed calculation and position calculation are based on the convergence of the sliding mode. Therefore, the calculated estimated current needs to be repeatedly corrected.

[0031] In this embodiment, a first correction value is determined based on the real-time current and the first estimated current, where MaxSMCError is a limit value defined in the program by the SMO sliding mode observer. Based on existing technology, the expression for h is: Therefore, if the right-hand side of the expression is the output of the simplified sliding mode observer, satisfying the condition of being less than and (i.e., less than the maximum error in the program), it means the sliding mode observer is in a convergent state, and the estimated current will converge to the actual current, eventually reaching and remaining on the sliding surface. For error values ​​outside the linear range, the output of the sliding mode observer is... or This depends on the sign of the error. The output is the first correction value. Essentially... It is a positive value, and the sign is determined by the first error current.

[0032] In one embodiment, determining the estimated rotational speed via a second sliding mode observer includes: Obtain real-time current and real-time voltage; Establish a second current observer model; The real-time current and the real-time current are input into the second current observer model to obtain the second estimated current; The second error current is obtained based on the second estimated current and the real-time current; The second correction value is determined based on the first electrical angle, the second electrical angle, the real-time current, and the second estimated current. The second estimated back EMF is obtained according to the second correction value, the second error current and the switching function; The third electrical angle is obtained according to the second estimated back EMF; The estimated rotational speed is determined according to the third electrical angle.

[0033] In the embodiment, the second sliding mode observer determines the electrical angle and the estimated rotational speed in the same way as the first sliding mode observer, except that the first correction value and the second correction value are different, the second correction value is a value that tends to decrease, and the first correction value is not.

[0034] In one embodiment, the second correction value is determined according to the first electrical angle, the second electrical angle, the real-time current and the second estimated current, comprising: An intermediate correction value is determined according to the real-time current and the second estimated current; The second correction value is determined by The second correction value is determined by The second correction value is adjusted according to the change of the angle difference value and the change of the second correction value; Wherein, The first electrical angle is The second electrical angle is c1 is the intermediate correction value, and c2 is the preset correction value.

[0035] In the embodiment, the intermediate correction value is determined in the same way as the first correction value.

[0036] In the embodiment, the preset correction value can adopt the average value of the first correction value in the historical record.

[0037] In one embodiment, the second correction value is adjusted according to the change of the angle difference value and the change of the second correction value, comprising: The absolute value of the latest angle difference value is obtained; The absolute value of the last angle difference value is obtained; It is judged whether the absolute value of the latest angle difference value is less than the absolute value of the last angle difference value, if yes, the second correction value is not adjusted, if not, the second correction value is adjusted according to the change of the latest second correction value.

[0038] In the embodiment, after the second correction value is obtained, the second correction value needs to be adjusted. This depends on whether the absolute value of the angle difference value decreases, if yes, the direction of change is correct, and no adjustment is needed, if not, the direction of change is wrong, and adjustment is needed.

[0039] In one embodiment, the second correction value is adjusted according to the change of the latest second correction value, comprising: The change amplitude x is obtained by The change amplitude x is obtained by determines whether the variation amplitude is greater than 0, if yes, the second correction value is adjusted by obtains the adjusted second correction value, if no, the second correction value is adjusted by obtains the adjusted second correction value; wherein C1 is the latest second correction value, and C0 is the previous second correction value of C1.

[0040] In the embodiment, if the variation amplitude is greater than 0, since the second correction value is positive, then is positive, which means that the second correction value is increasing, but the direction is wrong, so it is necessary to greatly reduce the variation of the second correction value, so the second correction value is adjusted by . Anyway, if the variation amplitude is smaller or unchanged, then is negative, which means that the second correction value is decreasing, at this time the second correction value is adjusted by obtains the adjusted second correction value, and the second correction value is slightly increased after adjustment.

[0041] As shown in Figure 2 , in one embodiment, a control device of a motor driver is provided, which can specifically include: a speed determination module, configured to determine a first speed and a second speed according to a target speed; a first control module, configured to determine whether an estimated speed is less than the first speed every other preset time, if yes, determine the estimated speed by high-frequency signal injection; a difference calculation module, configured to, if the estimated speed is greater than or equal to the first speed, determine whether the estimated speed is greater than the second speed, if no, determine a first electrical angle by high-frequency signal injection, determine a second electrical angle by a first sliding mode observer, and calculate an angle difference between the first electrical angle and the second electrical angle; a second control module, configured to execute different schemes according to a comparison between the angle difference and 0: if the angle difference is greater than 0, determine the estimated speed according to the first electrical angle; a third control module, configured to, if the angle difference is less than 0, determine the estimated speed by a second sliding mode observer; a fourth control module, configured to, if the angle difference is equal to 0, determine the estimated speed according to the second electrical angle; a fifth control module, configured to, if the estimated speed is greater than the second speed, determine the estimated speed by the first sliding mode observer.

[0042] In the embodiment, each module of the control device of the motor driver is modularized in the method part of the present application, and specific explanations of each module are referred to the corresponding content in the method part of the present application, which will not be described herein again.

[0043] As shown in Figure 3As shown, in one embodiment, a motor driver is provided, which can specifically include: a control module, a power conversion module, a detection module; The control module is configured to execute the steps of the control method of the motor driver; The power conversion module is connected to the control module and is configured to perform power control on the motor according to the control module; The detection module is connected to the control module and is configured to monitor the real-time current and real-time voltage of the motor.

[0044] In this embodiment, the motor driver further includes a power module and other modules.

[0045] In this embodiment, the detection module is a current sensor and a voltage sensor. The power conversion module converts the input computer into a variable voltage required for the operation of the motor.

[0046] The motor driver provided by the embodiment of the present application determines the first rotating speed and the second rotating speed according to the target rotating speed; every other preset time, it is determined whether the estimated rotating speed is less than the first rotating speed, if yes, the estimated rotating speed is determined through high-frequency signal injection; if the estimated rotating speed is greater than or equal to the first rotating speed, it is determined whether the estimated rotating speed is greater than the second rotating speed, if no, the first electric angle is determined through high-frequency signal injection, the second electric angle is determined through the first sliding mode observer, and the angle difference between the first electric angle and the second electric angle is calculated; different schemes are executed according to the comparison between the angle difference and 0: if the angle difference is greater than 0, the estimated rotating speed is determined according to the first electric angle; if the angle difference is less than 0, the estimated rotating speed is determined through the second sliding mode observer; if the angle difference is equal to 0, the estimated rotating speed is determined according to the second electric angle; if the estimated rotating speed is greater than the second rotating speed, the estimated rotating speed is determined through the first sliding mode observer. In this way, in the process of switching between the high-frequency injection and the sliding mode observer, that is, in the interval between the first rotating speed and the second rotating speed, every other preset time, the estimated rotating speed is determined in different ways according to the angle difference between the first electric angle and the second electric angle, until the angle difference is equal to 0 and the estimated rotating speed is determined through the first sliding mode observer, only one way is selected to determine the estimated rotating speed each time and the trend is close to 0, which solves the problem of inaccurate estimation result in the switching process.

[0047] Figure 4 The internal structure of the control module in one embodiment is shown. As Figure 4As shown, the control module includes a processor, a memory, a network interface, an input device, and a display screen connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium of the control module stores an operating system and may also store a computer program. When executed by the processor, this computer program enables the processor to implement the control method for a motor driver provided in this embodiment of the invention. The internal memory may also store a computer program, which, when executed by the processor, enables the processor to execute the control method for a motor driver provided in this embodiment of the invention. The display screen of the control module can be a liquid crystal display (LCD) or an electronic ink display. The input device of the control module can be a touch layer covering the display screen, or buttons, a trackball, or a touchpad mounted on the control module's casing, or an external keyboard, touchpad, or mouse, etc.

[0048] Those skilled in the art will understand that Figure 4 The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the control module to which the present invention is applied. The specific control module may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0049] In one embodiment, the control device for a motor driver provided by the present invention can be implemented as a computer program, and the computer program can be implemented as follows: Figure 4 The control module shown operates on this system. The memory of the control module can store the various program modules that make up the control device of the motor driver, for example... Figure 2 The diagram shows a speed determination module, a first control module, a difference calculation module, a second control module, a third control module, a fourth control module, and a fifth control module. The computer program comprised of these modules causes the processor to execute the steps of a motor driver control method according to various embodiments of the present invention described in this specification.

[0050] For example, Figure 4 The control module shown can be used as follows Figure 2 The speed determination module in the control device of the motor driver shown executes step S101; the control module can execute step S102 through the first control module; the control module can execute step S103 through the difference calculation module; the control module can execute step S104 through the second control module; the control module can execute step S105 through the third control module; the control module can execute step S106 through the fourth control module; and the control module can execute step S107 through the fifth control module.

[0051] In one embodiment, a control module is provided, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: S101, determining a first rotation speed and a second rotation speed according to a target rotation speed; S102, determining whether an estimated rotation speed is less than the first rotation speed every other preset time, and if so, determining the estimated rotation speed through high-frequency signal injection; S103, if the estimated rotation speed is greater than or equal to the first rotation speed, determining whether the estimated rotation speed is greater than the second rotation speed, and if not, determining a first electrical angle through high-frequency signal injection, determining a second electrical angle through a first sliding mode observer, and calculating an angle difference between the first electrical angle and the second electrical angle; S104, performing different schemes according to a comparison between the angle difference and 0: if the angle difference is greater than 0, determining the estimated rotation speed according to the first electrical angle; S105, if the angle difference is less than 0, determining the estimated rotation speed through a second sliding mode observer; S106, if the angle difference is equal to 0, determining the estimated rotation speed according to the second electrical angle; S107, if the estimated rotation speed is greater than the second rotation speed, determining the estimated rotation speed through the first sliding mode observer.

[0052] In one embodiment, a computer readable storage medium is provided, having a computer program stored thereon, wherein the computer program is executable by a processor to cause the processor to implement the following steps: S101, determining a first rotation speed and a second rotation speed according to a target rotation speed; S102, determining whether an estimated rotation speed is less than the first rotation speed every other preset time, and if so, determining the estimated rotation speed through high-frequency signal injection; S103, if the estimated rotation speed is greater than or equal to the first rotation speed, determining whether the estimated rotation speed is greater than the second rotation speed, and if not, determining a first electrical angle through high-frequency signal injection, determining a second electrical angle through a first sliding mode observer, and calculating an angle difference between the first electrical angle and the second electrical angle; S104, performing different schemes according to a comparison between the angle difference and 0: if the angle difference is greater than 0, determining the estimated rotation speed according to the first electrical angle; S105, if the angle difference is less than 0, determining the estimated rotation speed through a second sliding mode observer; S106, if the angle difference is equal to 0, determining the estimated rotation speed according to the second electrical angle; S107, if the estimated rotation speed is greater than the second rotation speed, determining the estimated rotation speed through the first sliding mode observer.

[0053] It should be understood that, although the steps in the flowcharts of the embodiments of the present application are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, at least some of the steps in the embodiments can include a plurality of sub-steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or sub-steps or stages of other steps. It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware, and the program can be stored in a non-volatile computer readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments of the method. Any reference to memory, storage, database or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0054] Any combination of the technical features of the above-mentioned embodiments can be combined. In order to make the description simple, all possible combinations of the technical features in the above-mentioned embodiments are not described, but as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0055] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application.

Claims

1. A control method of a motor driver characterized by comprising: The control method of the motor driver comprises: determining a first rotation speed and a second rotation speed according to a target rotation speed; every other preset time, judging whether the estimated rotation speed is less than the first rotation speed, if yes, determining the estimated rotation speed through high-frequency signal injection; if the estimated rotation speed is greater than or equal to the first rotation speed, judging whether the estimated rotation speed is greater than the second rotation speed, if no, determining a first electrical angle through high-frequency signal injection, determining a second electrical angle through a first sliding mode observer, and calculating an angle difference between the first electrical angle and the second electrical angle; according to a comparison between the angle difference and 0, executing different schemes: if the angle difference is greater than 0, determining the estimated rotation speed according to the first electrical angle; if the angle difference is less than 0, determining the estimated rotation speed through a second sliding mode observer; if the angle difference is equal to 0, determining the estimated rotation speed according to the second electrical angle; if the estimated rotation speed is greater than the second rotation speed, determining the estimated rotation speed through the first sliding mode observer.

2. The control method of the motor driver according to claim 1, characterized by, The method further comprises: From a first rotational speed is obtained; from a second rotational speed is obtained; wherein, is a target rotation speed, a is a first preset ratio, b is a second preset ratio, and a is less than b.

3. The control method of the motor driver according to claim 1, characterized by, The method further comprises: injecting a high-frequency voltage signal into the motor and extracting a high-frequency current response using a band-pass filter; determining an error signal according to the high-frequency current response; inputting the error signal into a proportional-integral observer to obtain the first electrical angle; determining the estimated rotation speed according to a change amount of the first electrical angle.

4. The control method of the motor driver according to claim 1, characterized by, The method further comprises: obtaining a real-time current and a real-time voltage; establishing a first current observer model; inputting the real-time current and the real-time current into the first current observer model to obtain a first estimated current; determining a first error current according to the first estimated current and the real-time current; determining a first correction value according to the real-time current and the first estimated current; determining a first estimated back electromotive force according to the first correction value, the first error current and a switching function; determining the second electrical angle according to the first estimated back electromotive force.

5. The control method of the motor driver according to claim 1, characterized by, The method further comprises: obtaining a real-time current and a real-time voltage; establishing a second current observer model; inputting the real-time current and the real-time current into the second current observer model to obtain a second estimated current; determining a second error current according to the second estimated current and the real-time current; determining a second correction value according to the first electrical angle, the second electrical angle, the real-time current and the second estimated current; determining a second estimated back electromotive force according to the second correction value, the second error current and a switching function; determining a third electrical angle according to the second estimated back electromotive force; determining the estimated rotation speed according to the third electrical angle.

6. The control method of the motor driver according to claim 5, characterized by, The method further comprises: determining an intermediate correction value according to the real-time current and the second estimated current; determined by determining a second correction value; adjusting the second correction value according to a change of the angle difference and a change of the second correction value; wherein, is a first electrical angle, is a second electrical angle, c1 is an intermediate correction value, and c2 is a preset correction value.

7. The control method of the motor driver according to claim 6, characterized by, The method further comprises: obtaining an absolute value of a latest angle difference; obtaining an absolute value of a previous angle difference; The absolute value of the latest angle difference value is compared with the absolute value of the previous angle difference value, if the absolute value of the latest angle difference value is smaller than the absolute value of the previous angle difference value, the second correction value is not adjusted, if the absolute value of the latest angle difference value is larger than the absolute value of the previous angle difference value, the second correction value is adjusted according to the change of the latest second correction value.

8. The control method of the motor driver according to claim 7, characterized by, The adjusting the second correction value according to the change of the latest second correction value comprises: from obtaining a variation amplitude x; determining whether the variation range is greater than 0, if yes, obtaining the adjusted second correction value by obtaining the adjusted second correction value, if no, obtaining the adjusted second correction value by obtaining the adjusted second correction value. Wherein, C1 is the latest second correction value, C0 is the previous second correction value of C1.

9. A control device of a motor driver characterized by comprising: The control device of the motor driver comprises: The speed determination module is configured to determine the first speed and the second speed according to the target speed; The first control module is configured to determine whether the estimated speed is smaller than the first speed every other preset time, if yes, the estimated speed is determined by the high-frequency signal injection; The difference calculation module is configured to determine whether the estimated speed is greater than the second speed if the estimated speed is greater than or equal to the first speed, if no, the first electrical angle is determined by the high-frequency signal injection, the second electrical angle is determined by the first sliding mode observer, and the angle difference between the first electrical angle and the second electrical angle is calculated; The second control module is configured to execute different schemes according to the comparison between the angle difference and 0: if the angle difference is greater than 0, the estimated speed is determined according to the first electrical angle; The third control module is configured to determine the estimated speed by the second sliding mode observer if the angle difference is smaller than 0; The fourth control module is configured to determine the estimated speed according to the second electrical angle if the angle difference is equal to 0; The fifth control module is configured to determine the estimated speed by the first sliding mode observer if the estimated speed is greater than the second speed.

10. An electric motor drive, characterized by The motor driver comprises a control module, a power conversion module and a detection module; The control module is configured to execute the steps of the control method of the motor driver according to any one of claims 1 to 8; The power conversion module is connected with the control module and is configured to perform power control on the motor according to the control module; The detection module is connected with the control module and is configured to monitor the real-time current and real-time voltage of the motor.

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