Starting method and device of brushless motor and computer equipment

Abstract

The invention discloses a brushless motor starting method and device and computer equipment, and the method comprises the steps: obtaining a voltage base value UqBase which enables a rotor of a brushless motor to be started at a plurality of cogging torque gaps in a no-load manner; starting the brushless motor according to the voltage base value UqBase; in the starting process of the brushless motor, detecting a speed value fed back by the switch Hall in real time; when the speed value is lower than the threshold speed, a second speed ring is adopted for control, and a dynamic Uq compensation control mechanism is adopted so that the brushless motor can be rapidly and stably started under the no-load and on-load conditions; and when the speed value reaches the set threshold speed, the speed ring I is adopted for control, and a conventional current closed-loop control mechanism is switched to enable the brushless motor to be stably switched between the speed ring II and the speed ring I. According to the starting method and device of the brushless motor, the computer equipment and the storage medium, a conventional current closed loop can be smoothly switched, an integral saturation problem is not generated, and abnormal electromagnetic noise does not exist.

Description

Technical Field

[0001] The present invention relates to the technical field of brushless motors, and in particular to a method and device for starting a brushless motor and a computer device. Background Art

[0002] With the continuous development of automatic control technology and electronic technology, field-oriented control is widely used in the control technology of three-phase AC motors. Field-oriented control (FOC) is also called vector control. It is a technology that uses a variable frequency drive (VFD) to control a three-phase AC motor. It controls the output of the motor by adjusting the output frequency, output voltage and angle of the variable frequency drive. Its characteristic is that it can control the magnetic field and torque of the motor individually, similar to the characteristics of a separately excited DC motor. Since the three-phase output current and voltage are represented by vectors during processing, it is called vector control. It is currently the best choice for efficient control of brushless DC motors (BLDC) and permanent magnet synchronous motors (PMSM). FOC accurately controls the size and direction of the magnetic field, making the motor torque stable, low noise, high efficiency, and high-speed dynamic response. Due to the obvious advantages of FOC, it has gradually replaced traditional control methods in many applications and has attracted much attention in the motion control industry.

[0003] In particular, the brushless motor driver with FOC control for switch Hall position feedback has the advantages of closed-loop startup and cost, strong load capacity, and the advantage of non-reversal at startup. Underwater cleaning robots are also driven by permanent magnet synchronous motors (PMSM). The walking motor drive of underwater cleaning robots usually adopts speed closed-loop control, with the outer control loop being the speed closed-loop and the inner control loop being the current loop, where the current loop is a double closed-loop of Iq (input current of the q-axis of the permanent magnet synchronous motor) and Id (input current of the d-axis of the permanent magnet synchronous motor), such as Figure 1 As shown, the output torque is mainly determined by the Iq current and the Iq, Id synthesis vector.

[0004] However, when the control adopts traditional FOC closed-loop control, for brushless motors with large cogging torque and small inductance, especially in the static starting stage, in order to overcome the motor's own cogging torque, the Iq current needs to be increased to a large enough level before the torque generated is sufficient to drag the motor to rotate. This current rise process usually takes a long time, and the back electromotive force is small in the starting stage. Due to the Iq current closed loop, the actual Iq current feedback value will fluctuate, causing high-frequency fluctuations in the Uq voltage, making it impossible for the synthetic current vector to output the desired torque, generating motor noise, long starting time, insufficient starting torque, and even motor reversal. When the Iq open loop is used, that is, the Uq (the output voltage of the q-axis of the permanent magnet synchronous motor) voltage is determined by the external input signal, there is no dynamic automatic adjustment of the Uq function, and it is impossible to automatically match the load. Summary of the invention

[0005] Based on this, it is necessary to provide a brushless motor starting method, device and computer equipment to address the above-mentioned motor noise, long starting time, insufficient starting torque, even motor reversal, and the lack of dynamic automatic adjustment of Uq function and inability to automatically match load technical problems.

[0006] A method for starting a brushless motor comprises the following steps:

[0007] Obtaining a voltage base value Uq_Base, wherein the voltage base value Uq_Base enables the rotor of the brushless motor to start without load at multiple tooth slot torque virtual positions;

[0008] The brushless motor is started according to the voltage base value Uq_Base;

[0009] During the start-up process of the brushless motor, the speed value from the switch Hall feedback is detected in real time;

[0010] When the speed value is lower than the threshold speed, the speed loop 2 control is adopted, and the dynamic Uq compensation control mechanism is adopted to enable the brushless motor to start quickly and stably under no-load and load conditions;

[0011] When the speed value reaches the set threshold speed, speed loop one control is adopted, and the conventional current closed-loop control mechanism is switched to enable the brushless motor to switch smoothly between speed loop two and speed loop one.

[0012] In one embodiment, the step of obtaining a voltage base value Uq_Base, which enables the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions, includes:

[0013] Record the minimum starting Uq voltage at which the brushless motor rotor can start without load at each tooth slot torque virtual position, and obtain multiple minimum starting Uq voltages;

[0014] The largest voltage among multiple minimum starting Uq voltages is selected as the voltage base value Uq_Base.

[0015] In one embodiment, the step of recording the minimum starting Uq voltage at which the rotor of the brushless motor can start without load at each tooth slot torque virtual position to obtain multiple minimum starting Uq voltages includes:

[0016] The rotor position of the current brushless motor is defined as the first angular position and marked;

[0017] Change the Uq voltage source to manual setting, set the Ud voltage to 0, and then gradually adjust the Uq voltage from small to large to determine the minimum Uq voltage required for no-load starting at the current position and record it;

[0018] Rotate the rotor to the next tooth slot torque virtual position, determine the minimum starting Uq voltage at the current position again, and record it, and so on, to obtain multiple minimum starting Uq voltages.

[0019] In one embodiment, the dynamic Uq compensation control mechanism includes:

[0020] Keep Ud given as 0;

[0021] Perform proportional and integral operations based on the difference between speed feedback and given speed;

[0022] The result of the operation Uq_Comp is used as the compensation value;

[0023] The sum of the obtained voltage base value Uq_Base and the real-time compensation value Uq_Comp is used as the given value of the final Uq voltage.

[0024] In one embodiment, the switching conventional current closed-loop control mechanism includes:

[0025] Convert the current Iq current into the initial integral of speed loop 1;

[0026] Clears the compensation value and the integral margin in the step when the speed value is lower than the threshold speed.

[0027] A starting device for a brushless motor, comprising:

[0028] An acquisition module, the acquisition module is used to acquire a voltage base value Uq_Base, the voltage base value Uq_Base can enable the rotor of the brushless motor to start without load at multiple tooth slot torque virtual positions;

[0029] A starting module, the starting module is used to start the brushless motor according to the voltage base value Uq_Base;

[0030] A detection module, wherein the detection module is used to detect the speed value from the switch Hall feedback in real time during the start-up process of the brushless motor;

[0031] Processing module 1, the processing module 1 is used to adopt speed loop 2 control when the speed value is lower than the threshold speed, and adopt a dynamic Uq compensation control mechanism to enable the brushless motor to start quickly and stably under no-load and loaded conditions;

[0032] Processing module 2, the processing module 2 is used to adopt speed loop 1 control when the speed value reaches the set threshold speed, switch the conventional current closed-loop control mechanism to make the brushless motor switch smoothly between speed loop 2 and speed loop 1.

[0033] A computer device comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of any one of the methods described above.

[0034] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of any of the methods described above.

[0035] The above-mentioned brushless motor starting method, device, computer equipment and storage medium obtain a voltage base value Uq_Base that enables the brushless motor's rotor to start at no-load at multiple tooth slot torque virtual positions, and then start the brushless motor based on the voltage base value Uq_Base. In the process of starting the brushless motor, the speed value from the switch Hall feedback is detected in real time, and speed loop two control and speed loop one control are respectively adopted according to the size relationship between the speed value and the threshold speed, thereby achieving fast starting within no-load and rated load, and in particular, it can smoothly switch to a conventional current closed loop without generating integral saturation problems, with a short starting time and without abnormal electromagnetic noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the drive control loop structure of a brushless motor in the prior art;

[0037] Figure 2 A schematic diagram of a flow chart of a method for starting a brushless motor in one embodiment;

[0038] Figure 3 A schematic diagram of a drive control loop structure for obtaining a voltage base value in one embodiment;

[0039] Figure 4 A schematic diagram of a process for obtaining a voltage base value in one embodiment;

[0040] Figure 5 Schematic diagram of a loop structure using speed loop 2 control in one embodiment;

[0041] Figure 6 A schematic diagram of a process of switching speed loop 2 or speed loop 1 in an embodiment;

[0042] Figure 7 is a structural block diagram of a starting device for a brushless motor in one embodiment;

[0043] Figure 8 Schematic diagram of the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0044] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0045] See also Figure 2 The present invention provides a method 10 for starting a brushless motor, and the method 10 for starting a brushless motor comprises the following steps:

[0046] Step S101 : obtaining a voltage base value Uq_Base, wherein the voltage base value Uq_Base enables the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions.

[0047] Step S102: starting the brushless motor according to the voltage base value Uq_Base.

[0048] Step S103: During the start-up process of the brushless motor, the speed value fed back from the switch Hall is detected in real time.

[0049] Step S104: when the speed value is lower than the threshold speed, the speed loop 2 control is adopted, and the dynamic Uq compensation control mechanism is adopted to enable the brushless motor to start quickly and stably under no-load and loaded conditions.

[0050] Step S105: When the speed value reaches the set threshold speed, the speed loop 1 control is adopted, and the conventional current closed-loop control mechanism is switched to enable the brushless motor to switch smoothly between the speed loop 2 and the speed loop 1.

[0051] The above-mentioned brushless motor starting method 10 obtains a voltage base value Uq_Base that enables the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions, and then starts the brushless motor based on the voltage base value Uq_Base. In the process of starting the brushless motor, the speed value from the switch Hall feedback is detected in real time, and speed loop two control and speed loop one control are respectively adopted according to the relationship between the speed value and the threshold speed, so as to achieve fast starting within no-load and rated load, and in particular, it can smoothly switch to a conventional current closed loop without generating integral saturation problems, with a short starting time and without abnormal electromagnetic noise.

[0052] For step S101, specifically, the cogging torque is the torque generated by the interaction between the permanent magnet and the stator core when the permanent magnet motor winding is not energized, and is caused by the tangential component of the interaction force between the permanent magnet and the armature teeth. When the output voltage Ud of the d-axis of the permanent magnet synchronous motor is set to 0, the minimum Uq voltage that can make the motor rotate by overcoming the cogging torque is the minimum Uq voltage that the brushless motor can start at no-load at the current cogging torque virtual position. In the absence of load, under the action of this minimum Uq voltage, the brushless motor can overcome the cogging torque and make the rotor rotate at no-load.

[0053] It should be noted that there are multiple magnetic poles and core teeth in the brushless DC motor, that is, there are multiple tooth torque virtual positions (the magnetic lines of force of the permanent magnet rotor in the motor will naturally pull the rotor to the position where the magnetic resistance path is the smallest). Therefore, in the process of obtaining the voltage base value Uq_Base, it is necessary to detect the minimum starting Uq voltage that can be started without load at each tooth torque virtual position. In one embodiment, the step of obtaining the voltage base value Uq_Base, which enables the rotor of the brushless motor to start without load at multiple tooth torque virtual positions, includes: recording the minimum starting Uq voltage that can start the rotor of the brushless motor without load at each tooth torque virtual position, and obtaining multiple minimum starting Uq voltages; selecting the largest voltage among the multiple minimum starting Uq voltages as the voltage base value Uq_Base.

[0054] It can be understood that by using the maximum voltage value among multiple minimum starting Uq voltages as the starting Uq voltage for no-load starting of the rotor at the cogging torque virtual position, this maximum voltage value can definitely enable the rotor to start no-load at each cogging torque virtual position. In this way, using the maximum voltage among multiple minimum starting Uq voltages as the voltage base value Uq_Base solves the problem of uneven starting voltage caused by uneven cogging torque and different required torques, so that the rotor can be started no-load at each cogging torque virtual position.

[0055] However, how to obtain the minimum starting Uq voltage that can be started at no-load at each tooth slot torque virtual position is particularly important. Therefore, in one embodiment, the step of recording the minimum starting Uq voltage that can be started at no-load at each tooth slot torque virtual position of the brushless motor rotor to obtain multiple minimum starting Uq voltages includes: defining the current rotor position of the brushless motor as the first angular position and marking it; changing the Uq voltage source to manual setting, setting the Ud voltage to 0, and then gradually adjusting the Uq voltage from small to large, determining the minimum Uq voltage required for no-load starting at the current position, and recording it; rotating the rotor to the next tooth slot torque virtual position, determining the minimum starting Uq voltage at the current position again, and recording it, and so on, to obtain multiple minimum starting Uq voltages.

[0056] Take the motor of an underwater cleaning robot or a swimming pool cleaning machine as an example. They all use FOC control. Three switch Halls with an electrical angle distribution of 120 degrees are used to identify the position of the motor rotor. The control loop is an outer speed closed loop and an inner current inner loop. The verification motor has 4 pairs of poles and 6 slots. The external force rotates the rotor. There is a tooth torque virtual position every 60 degrees of electrical angle. There are 24 tooth slot virtual positions for 4 pairs of poles. In the absence of external force, the rotor will eventually stop at the tooth torque virtual position angle, that is, the magnetic field lines of the permanent magnet rotor in the motor will naturally pull the rotor to the position with the smallest magnetic resistance path.

[0057] like Figure 3 and Figure 4 As shown, the lowest Uq voltage calibration is the minimum starting Uq voltage calibration. The current rotor position is defined as the first angular position and marked. Change the Uq voltage source to manual setting. Set the Ud voltage to 0, and then gradually adjust the Uq voltage from small to large to determine the minimum Uq voltage required for no-load starting at the current position, and record it; then rotate the rotor to the next tooth slot torque virtual position, and determine the minimum starting Uq voltage at the current position again, and record it. Rotate a total of 6 positions in this way to ensure that it can start smoothly when no-load. Finally, record a total of 6 Uq voltage values, and take the largest voltage as the Uq voltage base value, that is, Uq_Base, to solve the problem of uneven tooth slot torque and different required torque.

[0058] For step S102, specifically, the brushless motor is started based on the voltage base value Uq_Base. Since the voltage base value Uq_Base at this time can start the brushless motor under no-load state, the insufficient torque, motor noise, long starting time, insufficient starting torque, and even motor reversal caused by uneven tooth slot torque can be avoided after starting the brushless motor in this step. Therefore, based on the voltage base value Uq_Base, the starting torque is sufficient, so that the brushless motor starts smoothly without noise. In this way, only the threshold speed of the brushless motor can be paid attention to, and the control mechanism of the loop can be switched according to the size of the threshold speed, so that the brushless motor is more stable during the entire starting process.

[0059] For step S103, specifically, the switch Hall is also called the Hall position sensor. The function of the Hall position sensor is to sense the position of the object to be measured and convert it into a usable output signal, which is used to detect the position and reflect the switch of a certain state of a certain component. To this end, the switch Hall installed in the brushless motor and distributed at a preset position with a preset electrical angle can be used to detect the speed value of the brushless motor during the startup process in real time. For example, three switch Halls with an electrical angle distribution of 120 degrees are used to identify the motor rotor position. That is to say, the three switch Halls are distributed in the brushless motor along the rotation direction of the rotor, 120 degrees apart from each other.

[0060] In this step, the speed value from the switch Hall feedback is detected in real time during the startup process, the speed value from the switch Hall feedback is compared with the threshold speed, and the control mechanism of the brushless motor control loop is adjusted according to the comparison result. In order to ensure the smoothness of switching between different control mechanisms, the detection frequency of the switch Hall is real-time detection, so that the switching response can be quickly made according to the speed value at the first time to ensure the smoothness of switching between different control mechanisms. It should be noted that the speed value can be the angular velocity ω of the brushless motor rotor, or it can be the number of revolutions n of the brushless motor rotor. The threshold speed can be a threshold angular velocity or a threshold number of revolutions. In order to facilitate unified understanding, in various embodiments of the present invention, the speed value is the angular velocity ω, and the threshold speed can be the threshold angular velocity.

[0061] For step S104, different from conventional FOC control, the modification of the startup speed loop is divided into before and after the threshold speed. Figure 5 As shown, Figure 5 A schematic diagram of the loop structure using speed loop 2 control is shown. When the speed value is lower than the threshold speed, speed loop 2 control is adopted, and a dynamic Uq compensation control mechanism is adopted so that the brushless motor can start quickly and stably under no-load and load conditions. That is to say, the speed value from the switch Hall feedback is detected in real time during the startup process, and when the speed is lower than the threshold speed, speed loop 2 control is adopted. Preferably, in one embodiment, the dynamic Uq compensation control mechanism includes: keeping the Ud given at 0; performing proportional and integral operations based on the difference between the speed feedback and the speed given; using the result Uq_Comp after the operation as the compensation value; and using the sum of the obtained voltage base value Uq_Base and the real-time compensation value Uq_Comp as the final Uq voltage given value.

[0062] It should be noted that the second speed loop control, i.e. the dynamic Uq compensation control of the present invention, is adopted, and the Ud setting is kept at 0, i.e., proportional and integral operations are performed according to the difference between the speed feedback and the speed setting. The proportional and integral operations are calculated using the following formula, where Kp is the proportional coefficient, Ki is the integral coefficient, and e(k)

[0063]

[0064] The difference between the current speed given value and the feedback value, the output result u(k) is used as the compensation value, Uq = Uq_Comp + Uq_Base. The operation rules of the proportional and integral operation formulas can refer to the existing technology and will not be repeated here.

[0065] Furthermore, the result of the operation Uq_Comp is used as the compensation value, that is, the sum of the obtained voltage base value Uq_Base and the real-time compensation value Uq_Comp is used as the final given value of the Uq voltage, ensuring that the motor can start quickly and stably under no-load and load conditions. At this time, the speed loop 2 is running, the current loop is in an open-loop operation state, and the current loop integral is cleared in real time. It can be understood that the current loop adopts PI proportional / integral control, that is, the difference between the current set value and the real-time feedback value is used for proportional calculation (the difference is multiplied by a coefficient Kp to amplify it, which is only valid for the current difference calculation and is not accumulated) and integral calculation (the difference is multiplied by another coefficient Ki, and the result is added to the previous integral result. The difference calculation result is accumulated over time to form the current loop integral); when the speed control loop 2 is working, its output directly controls the Uq voltage compensation value output instead of controlling the Iq set value. At this time, the electric loop current d / q axis is in an open-loop state, so its integral accumulation is incorrect and needs to be cleared in real time to avoid affecting the operating stability when the speed loop 1 is switched later (it should be noted that the proportion, integral / integral amount, etc. in PI control are existing technologies and are classic control methods, which will not be repeated here).

[0066] For step S105, specifically, the comparison between the real-time speed value of the switch Hall feedback and the threshold speed is the key to determine whether to switch from speed loop 2 to speed loop 1. In this step, when the speed value reaches the set threshold speed, speed loop 1 control is adopted, that is, switching from speed loop 2 to speed loop 1, that is, switching the conventional current closed-loop control mechanism to enable the brushless motor to switch smoothly between speed loop 2 and speed loop 1. Preferably, the switching conventional current closed-loop control mechanism includes: converting the current Iq current into the initial integral of speed loop 1; clearing the compensation value and integral margin in the step when the speed value is lower than the threshold speed. It can be understood that when speed loop 1 is working (the current loop will also be in a closed-loop state, and when speed loop 2 is working, the current loop is in an open-loop state), its output result is the given value of the current loop Iq current, which is composed of the proportional amplification calculation of the speed difference and the integral accumulation calculation, wherein the proportional calculation is only the calculation of the current speed difference, and in particular the integral calculation is the cumulative calculation of the current and past speed differences; before switching, the motor has been running stably, and there is enough Iq current to generate enough torque to overcome the external load. In order to switch to speed loop 1 to run smoothly without step fluctuations (step fluctuations in the current given value will cause motor operation fluctuations), that is, to ensure that the Iq current fluctuations before and after the switch are as small as possible, it is necessary to reversely convert the Iq current feedback value during the current operation into the integral when the 'speed loop 1' is just running, so as to make up for the integral when the speed loop 1 is first run / calculated, that is, the "initial integral", and output a sufficient current given value. The compensation value and integral margin refer to the compensation value Uq_Comp of the speed loop 2 proportional integral operation in step S104, which is composed of the current speed difference value after proportional calculation and integral accumulation calculation, wherein the integral accumulation calculation part is the integral margin or integral amount, and the two values ​​are cleared here to prepare for the next startup to prevent the current data from affecting the next operation. In this way, the Iq current is converted into the initial integral amount of the speed loop 1, and the compensation value and integral margin in the step are cleared, which can ensure the smoothness of the switching between the two speed loops.

[0067] In this embodiment, when the feedback speed reaches the set threshold speed, the conventional current closed-loop control is switched, such as Figure 1 and Figure 6 As shown, in particular, the current Iq current is converted into the initial integral of the speed loop 1, and the compensation value and integral margin in the step are cleared, ensuring the smoothness of the switching between the two speed loops. It can be understood that when moving in the reverse direction, the Uq reference voltage and compensation value can be negative.

[0068] like Figure 7As shown, the present invention provides a brushless motor starting device, the brushless motor starting device comprises: an acquisition module 101, an acquisition module 102, a detection module 103, a processing module 104 and a processing module 2 105, wherein:

[0069] The acquisition module 101 is used to acquire a voltage base value Uq_Base, which enables the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions.

[0070] The acquisition module 102 is used to start the brushless motor according to the voltage base value Uq_Base.

[0071] The detection module 103 is used to detect the speed value from the switch Hall feedback in real time during the start-up process of the brushless motor.

[0072] The processing module 1 104 is used to adopt the speed loop 2 control when the speed value is lower than the threshold speed, and adopt the dynamic Uq compensation control mechanism to enable the brushless motor to start quickly and stably under no-load and loaded conditions.

[0073] The processing module 2 105 is used to adopt the speed loop 1 control and switch the conventional current closed-loop control mechanism to enable the brushless motor to switch smoothly between the speed loop 2 and the speed loop 1 when the speed value reaches the set threshold speed.

[0074] The acquisition module 101 includes a recording unit and a selection unit.

[0075] The recording unit is used to record the minimum starting Uq voltage at which the rotor of the brushless motor can start without load at each tooth slot torque virtual position, and obtain multiple minimum starting Uq voltages; the selection unit is used to select the largest voltage among the multiple minimum starting Uq voltages as the voltage base value Uq_Base.

[0076] The recording unit includes a definition marking unit, a voltage regulation recording unit and an analogy acquisition unit.

[0077] The definition marking unit is used to define the rotor position of the current brushless motor as the first angular position and mark it; the voltage regulation recording unit is used to change the Uq voltage source to manual setting, set the Ud voltage to 0, and then gradually adjust the Uq voltage from small to large, determine the minimum Uq voltage required for no-load starting at the current position, and record it; the analogy acquisition unit is used to rotate the rotor to the next tooth slot torque virtual position, determine the minimum starting Uq voltage at the current position again, and record it, and so on, to obtain multiple minimum starting Uq voltages.

[0078] The specific definition of the starting device of the brushless motor can be found in the definition of the starting method of the brushless motor above, which will not be repeated here. Each module in the above-mentioned starting device of the brushless motor can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0079] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 8 As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for starting a brushless motor is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0080] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0081] In one embodiment, the present invention provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the following steps are implemented:

[0082] A voltage base value Uq_Base is obtained, and the voltage base value Uq_Base can enable the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions; the brushless motor is started according to the voltage base value Uq_Base; during the start-up process of the brushless motor, the speed value from the switch Hall feedback is detected in real time; when the speed value is lower than the threshold speed, the speed loop 2 control is adopted, and the dynamic Uq compensation control mechanism is adopted so that the brushless motor can start quickly and stably under no-load and load conditions; when the speed value reaches the set threshold speed, the speed loop 1 control is adopted, and the conventional current closed-loop control mechanism is switched to enable the brushless motor to switch smoothly between the speed loop 2 and the speed loop 1.

[0083] In one embodiment, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the following steps are implemented:

[0084] A voltage base value Uq_Base is obtained, and the voltage base value Uq_Base can enable the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions; the brushless motor is started according to the voltage base value Uq_Base; during the start-up process of the brushless motor, the speed value from the switch Hall feedback is detected in real time; when the speed value is lower than the threshold speed, the speed loop 2 control is adopted, and the dynamic Uq compensation control mechanism is adopted so that the brushless motor can start quickly and stably under no-load and load conditions; when the speed value reaches the set threshold speed, the speed loop 1 control is adopted, and the conventional current closed-loop control mechanism is switched to enable the brushless motor to switch smoothly between the speed loop 2 and the speed loop 1.

[0085] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), 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).

[0086] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for starting a brushless motor, characterized in that: The steps include: Obtaining a voltage base value Uq_Base, wherein the voltage base value Uq_Base enables the rotor of the brushless motor to start without load at multiple tooth slot torque virtual positions; The brushless motor is started according to the voltage base value Uq_Base; During the start-up process of the brushless motor, the speed value from the switch Hall feedback is detected in real time; When the speed value is lower than the threshold speed, the speed loop 2 control is adopted, and the dynamic Uq compensation control mechanism is adopted to enable the brushless motor to start quickly and stably under no-load and load conditions; When the speed value reaches the set threshold speed, speed loop one control is adopted, and the conventional current closed-loop control mechanism is switched to enable the brushless motor to switch smoothly between speed loop two and speed loop one.

2. The method for starting a brushless motor according to claim 1, characterized in that: The step of obtaining a voltage base value Uq_Base, wherein the voltage base value Uq_Base enables the rotor of the brushless motor to start at no-load at multiple tooth slot torque virtual positions, comprises: Record the minimum starting Uq voltage at which the brushless motor rotor can start without load at each tooth slot torque virtual position, and obtain multiple minimum starting Uq voltages; The largest voltage among multiple minimum starting Uq voltages is selected as the voltage base value Uq_Base.

3. The method for starting a brushless motor according to claim 2, characterized in that: The step of recording the minimum starting Uq voltage at which the rotor of the brushless motor can be started without load at each tooth slot torque virtual position to obtain multiple minimum starting Uq voltages comprises: The rotor position of the current brushless motor is defined as the first angular position and marked; Change the Uq voltage source to manual setting, set the Ud voltage to 0, and then gradually adjust the Uq voltage from small to large to determine the minimum Uq voltage required for no-load starting at the current position and record it; Rotate the rotor to the next tooth slot torque virtual position, determine the minimum starting Uq voltage at the current position again, and record it, and so on, to obtain multiple minimum starting Uq voltages.

4. The method for starting a brushless motor according to claim 1, characterized in that: The dynamic Uq compensation control mechanism includes: Keep Ud given as 0; Perform proportional and integral operations based on the difference between speed feedback and given speed; The result of the operation Uq_Comp is used as the compensation value; The sum of the obtained voltage base value Uq_Base and the real-time compensation value Uq_Comp is used as the given value of the final Uq voltage.

5. The method for starting a brushless motor according to claim 4, characterized in that: The switching conventional current closed-loop control mechanism comprises: Convert the current Iq current into the initial integral of speed loop 1; Clears the compensation value and the integral margin in the step when the speed value is lower than the threshold speed.

6. A starting device for a brushless motor, characterized in that: include: An acquisition module, the acquisition module is used to acquire a voltage base value Uq_Base, the voltage base value Uq_Base can enable the rotor of the brushless motor to start without load at multiple tooth slot torque virtual positions; A starting module, the starting module is used to start the brushless motor according to the voltage base value Uq_Base; A detection module, wherein the detection module is used to detect the speed value from the switch Hall feedback in real time during the start-up process of the brushless motor; Processing module 1, the processing module 1 is used to adopt speed loop 2 control when the speed value is lower than the threshold speed, and adopt a dynamic Uq compensation control mechanism to enable the brushless motor to start quickly and stably under no-load and loaded conditions; Processing module 2, the processing module 2 is used to adopt speed loop 1 control when the speed value reaches the set threshold speed, switch the conventional current closed-loop control mechanism to make the brushless motor switch smoothly between speed loop 2 and speed loop 1.

7. The starting device of the brushless motor according to claim 6, characterized in that: The acquisition module includes a recording unit and a selection unit. The recording unit is used to record the minimum starting Uq voltage at which the rotor of the brushless motor can start without load at each tooth slot torque virtual position, and obtain multiple minimum starting Uq voltages; The selection unit is used to select the largest voltage among a plurality of minimum starting Uq voltages as the voltage base value Uq_Base.

8. The starting device of the brushless motor according to claim 7, characterized in that: The recording unit includes a definition marking unit, a voltage regulation recording unit and an analogy acquisition unit. The definition marking unit is used to define the current rotor position of the brushless motor as the first angular position and mark it; The voltage regulation recording unit is used to change the Uq voltage source to manual setting, set the Ud voltage to 0, and then gradually adjust the Uq voltage from small to large, determine the minimum Uq voltage required for no-load starting at the current position, and record it; The analogy acquisition unit is used to rotate the rotor to the next tooth slot torque virtual position, determine the minimum starting Uq voltage at the current position again, and record it, and so on, to obtain multiple minimum starting Uq voltages.

9. A computer device, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

Images