Adaptive starting method for non-inductive motor of electric massager

Abstract

The present application relates to the field of motor starting of electric massager, in particular to a kind of adaptive starting method of electric massager non-inductive motor, adaptive starting of electric massager is realized, and the adaptability and versatility of electric massager starting are greatly improved.The adaptive starting method of electric massager non-inductive motor of the present application includes: reading the first PWM duty cycle stored;The first PWM duty cycle read is corrected, and the second PWM duty cycle is obtained;Motor starting control is carried out according to the second PWM duty cycle;The first PWM duty cycle stored is updated.The present application is suitable for the adaptive starting of electric massager non-inductive motor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of motor starting of electric massagers, in particular to an adaptive starting method of a non-inductive motor of an electric massager. BACKGROUND

[0002] An electric massager, such as a fascia gun, is mainly composed of a battery, a motor and a control circuit board. The motor drives the massage head to make reciprocating motion through an eccentric wheel transmission, achieving the massage effect of hitting back and forth on the human body, with small size and being carried by the user.

[0003] The motor uses a direct-current inductive motor and a direct-current non-inductive motor. The inductive motor is composed of an armature core winding, a rotor magnet and a driving circuit board, the driving board and the motor are integrated, and the Hall sensor on the driving board can detect the rotor position in real time, facilitating the starting and running of the motor. The driving circuit board provides a motor control interface, which is controlled by the control board of the fascia gun to control the start and stop and the speed of the motor.

[0004] In order to further reduce the size and cost, the motor of the fascia gun is replaced from the inductive motor to the non-inductive motor. In this way, the motor driving board of the inductive motor can be omitted, and the control board of the fascia gun directly drives the armature winding commutation.

[0005] Since the motor driving board is cancelled, there is no Hall sensor under the motor, and the position of the rotor cannot be known when the non-inductive motor starts, so the position of the rotor magnet can only be determined according to the back electromotive force of the coil. Since the back electromotive force of the non-inductive motor is proportional to the speed of the motor, the back electromotive force is zero when the motor is stationary or very small when the motor is at low speed, so the position of the rotor magnet cannot be determined according to the back electromotive force signal at this time.

[0006] Therefore, the non-inductive motor back electromotive force starting method needs to use a special starting technology to start from static state and accelerate until the speed is large enough. When the zero-crossing is detected by the back electromotive force, the non-inductive motor is switched to the running state. This process is called "three-stage" starting, which mainly includes three stages of rotor pre-positioning, acceleration and running state switching. In this way, the motor rotation can be controlled, and the motor can be switched after reaching a certain speed, ensuring the reliability of the starting.

[0007] However, the non-inductive motor cannot detect the back electromotive force in the static state, so it can only accelerate the motor to a certain speed in an open-loop manner, so that the back electromotive force reaches a level that can detect the zero-crossing point, and then switch to closed-loop speed regulation. The so-called open-loop acceleration is to ignore the current position of the rotor, and forcibly commutate according to the set voltage and commutation frequency to drive the rotor to rotate. And gradually increase the commutation frequency to accelerate the rotation of the rotor.

[0008] In the open-loop acceleration process, the current position of the rotor is unknown, so the angle between the stator magnetic field and the rotor magnetic field cannot be controlled, and overcurrent or step loss is easily generated. If the rotor has reached the position aligned with the direction of the stator magnetic field without phase conversion, the current in the stator winding will be large, resulting in overcurrent. If phase conversion occurs before the rotor reaches the specified position, step loss is generated, which may make the direction of the stator magnetic field lag behind the rotor magnetic field, reverse the rotor, and then switch between forward rotation and reverse rotation, causing the rotor to swing repeatedly, and even finally resulting in a deadlock.

[0009] Further, due to the need for the fascia gun to reduce noise, etc., the distance between the motor piston rod and the sliding sleeve is very small, resulting in inconsistent tension between the sliding sleeves due to production tolerances and temperature changes during use, causing inconsistent loads on the motor. At the same time, the battery voltage on the fascia gun is variable, which causes the same acceleration curve to run on fascia guns with different loads and different voltages, resulting in inconsistent starting effects. For example, the same starting curve may encounter a large-load fascia gun, resulting in step loss due to the rotor being late to reach the specified position and phase conversion occurring before the rotor reaches the specified position. If a small-load fascia gun is encountered, the rotor may have reached the position aligned with the direction of the stator magnetic field without phase conversion, resulting in a large current in the stator winding and overcurrent. In extreme cases, the start may be unsuccessful, affecting product performance. In extreme cases, the small-load fascia gun may vibrate significantly during startup, and the large-load fascia gun may take too long to start, affecting user experience. SUMMARY

[0010] The purpose of the present application is to provide an adaptive starting method for a non-inductive motor of an electric massager, which realizes adaptive starting of the electric massager under different conditions and greatly improves the adaptability and universality of the electric massager startup.

[0011] The present application achieves the above-mentioned purpose by adopting the following technical solutions: an adaptive starting method for a non-inductive motor of an electric massager, comprising:

[0012] reading a stored first PWM duty cycle;

[0013] correcting the read first PWM duty cycle to obtain a second PWM duty cycle;

[0014] controlling motor startup according to the second PWM duty cycle;

[0015] updating the stored first PWM duty cycle.

[0016] Further, the correction of the read first PWM duty cycle to obtain a second PWM duty cycle specifically includes:

[0017] Collecting the current battery voltage, referring to the pre-stored battery voltage and PWM duty cycle corresponding relationship, reading the PWM duty cycle corresponding to the current battery voltage as the second PWM duty cycle.

[0018] Further, the specific method of pre-storing the battery voltage and PWM duty cycle corresponding relationship includes:

[0019] In the test phase, the fascia gun battery voltage is collected in real time, the PWM duty cycle required to maintain the motor winding end fixed voltage under different battery voltages is measured, and the corresponding relationship between the battery voltage and the PWM duty cycle is stored in the electric massager control module.

[0020] Further, the first PWM duty cycle is corrected to obtain the second PWM duty cycle, specifically including:

[0021] Collecting the current environment temperature, calculating the second PWM duty cycle according to the environment temperature according to the following formula:

[0022] P2=P1+K1*(T0-T), P2 is the second PWM duty cycle, P1 is the first PWM duty cycle; K1>0, and is a correction coefficient determined by testing, T0 is the threshold temperature, T is the real-time collected environment temperature.

[0023] Further, the first PWM duty cycle is updated, specifically: the first PWM duty cycle is updated according to the second PWM duty cycle.

[0024] Further, the method further includes:

[0025] Recording the actual motor starting time S1 this time;

[0026] According to the actual motor starting time S1 and the standard starting time S, the PWM duty cycle is compensated and corrected to calculate the third PWM duty cycle: P3=P2+K2*(S1-S), K2>0, and is a compensation correction coefficient determined by debugging, P3 is the third PWM duty cycle.

[0027] The first PWM duty cycle is updated, specifically: the first PWM duty cycle is updated according to the third PWM duty cycle.

[0028] Further, obtaining the standard starting time S specifically includes:

[0029] The second PWM duty cycle is loaded to the fascia gun motor, the motor winding end is kept at a constant voltage, a commutation time curve is pre-set in the fascia gun control module, and the fascia gun motor is started, and through debugging, the standard time S from static to detection of reverse electromotive force closed loop operation when starting smoothly is obtained.

[0030] An adaptive starting method of a non-inductive motor of an electric massager, comprising:

[0031] reading a stored first PWM duty cycle;

[0032] performing motor starting control according to the first PWM duty cycle;

[0033] recording an actual motor starting time S1 of this time;

[0034] correcting the first PWM duty cycle according to the actual motor starting time S1 and a standard starting time S to obtain a third PWM duty cycle;

[0035] updating the stored first PWM duty cycle according to the third PWM duty cycle.

[0036] Further, the correction of the first PWM duty cycle specifically comprises:

[0037] the correction is performed by using the following formula: P3=P1+K2*(S1-S), wherein P1 is the first PWM duty cycle, and P3 is the third PWM duty cycle.

[0038] The obtaining of the standard starting time S specifically comprises:

[0039] loading the first PWM duty cycle to a motor of a fascia gun to keep a constant voltage of a winding end of the motor, presetting a commutation time curve in a control module of the fascia gun, starting the motor of the fascia gun, and obtaining, through debugging, a standard time S from static state to closed-loop operation of detecting a reverse electromotive force when the motor is started smoothly.

[0040] Further, the electric massager is a fascia gun.

[0041] The present application has the following beneficial effects:

[0042] The present application corrects the read PWM duty cycle in real time during the starting process of the electric massager, and updates the stored PWM duty cycle by using the corrected PWM duty cycle, thereby realizing adaptive starting of the electric massager under different conditions and greatly improving the adaptability and universality of the starting of the electric massager.

[0043] The present application corrects the PWM duty cycle by using the current voltage, thereby reducing the influence of voltage change on the starting process of the electric massager.

[0044] Since the lower the temperature is, the tighter the sliding sleeve is, and the greater the motor load is, the starting voltage needs to be increased, and the higher the temperature is, the looser the sliding sleeve is, and the starting voltage needs to be reduced. Therefore, the present application corrects the current PWM duty cycle by collecting the ambient temperature in real time, thereby reducing the influence of the ambient temperature on the starting process of the electric massager.

[0045] By starting time measurement and comparison, the PWM duty cycle is compensated and corrected, and the adaptability of the whole starting process is improved. After compensation and correction, the PWM duty cycle is updated in the control module of the electric massager.

[0046] Through the above correction method, the PWM duty cycle is updated and corrected each time the restarts, making the starting process more suitable for the electric massager body, making up for the tolerance in the manufacturing process or the mechanical loss after long-term use of the sliding sleeve, and greatly improving the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The corresponding relationship curve between the battery voltage and the PWM duty cycle provided by the embodiment of the application is shown in the figure;

[0048] Figure 2 The actual measured battery voltage and PWM duty cycle curve during starting provided by the embodiment of the application is shown in the figure;

[0049] Figure 3 The first flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0050] Figure 4 The second flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0051] Figure 5 The third flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0052] Figure 6 The fourth flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0053] Figure 7 The fifth flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0054] Figure 8 The sixth flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure;

[0055] Figure 9 The seventh flowchart of the PWM duty cycle correction process provided by the embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0056] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present application.

[0057] In order to facilitate the understanding of the present application, before the description of the solutions, the basic principle of the present application is described. The basic principle of the present application is that a starting curve or a starting table or other starting function relationship is preset in the electric massager, in the running process, the preset starting curve or starting table or other starting function relationship is corrected through real-time battery voltage, ambient temperature and starting time, and the main parameters involved are saved and updated, so that the next time the starting is performed, the starting can be performed through the optimized starting curve or starting table or other starting function relationship, and the starting success, the stability and adaptability of the starting process are ensured.

[0058] The open-loop starting relationship mainly includes two important parameters, the voltage applied to the motor winding and the commutation time. There are usually three methods to set the starting relationship.

[0059] The fixed voltage is continuously shortened in the starting process to start, which is called constant voltage frequency increasing method. There is also a fixed commutation time, which is continuously improved in the voltage method, which is called constant frequency voltage increasing method. There is also a voltage rising and commutation time shortening in the starting process, which is called voltage rising and frequency increasing method.

[0060] According to the characteristics of the electric massager, the present application mainly adopts the constant voltage frequency increasing method for starting.

[0061] The adaptive starting method of the inductive motor of the electric massager of the present application comprises:

[0062] Reading the stored first PWM duty cycle;

[0063] Correcting the read first PWM duty cycle to obtain a second PWM duty cycle;

[0064] Controlling the motor starting according to the second PWM duty cycle;

[0065] Updating the stored first PWM duty cycle.

[0066] The real-time correction of the read PWM duty cycle in the starting process of the present application mainly includes three correction methods of voltage correction, temperature correction and starting time correction, and the three correction methods can be combined arbitrarily, and the specific conditions are as follows:

[0067] In one embodiment of the present application, the method for correcting the PWM duty cycle by the current voltage comprises the steps as shown in Figure 3

[0068] collecting the current battery voltage, referring to the pre-stored corresponding relationship between the battery voltage and the PWM duty cycle, reading the PWM duty cycle corresponding to the current battery voltage as the second PWM duty cycle.

[0069] updating the stored first PWM duty cycle according to the second PWM duty cycle.

[0070] The specific method for pre-storing the corresponding relationship between the battery voltage and the PWM duty cycle comprises:

[0071] collecting the battery voltage of the electric massager in real time in the test stage, measuring the PWM duty cycle required for maintaining the fixed voltage of the motor winding end under different battery voltages, and storing the corresponding relationship between the battery voltage and the PWM duty cycle into the control module of the electric massager.

[0072] In one embodiment of the present application, the method for correcting the PWM duty cycle by the current temperature comprises the steps as shown in Figure 4

[0073] collecting the current environment temperature, and calculating the second PWM duty cycle according to the environment temperature according to the following formula:

[0074] P2=P1+K1*(T0-T), P2 is the second PWM duty cycle, P1 is the first PWM duty cycle; K1>0, and is a correction coefficient determined by test, T0 is the threshold temperature, and T is the real-time collected environment temperature.

[0075] updating the stored first PWM duty cycle according to the second PWM duty cycle.

[0076] In one embodiment of the present application, the method for correcting the PWM duty cycle by the starting time comprises the steps as shown in Figure 5

[0077] reading the stored first PWM duty cycle;

[0078] controlling the motor starting according to the first PWM duty cycle;

[0079] recording the actual motor starting time S1 this time;

[0080] correcting the first PWM duty cycle according to the actual motor starting time S1 and the standard starting time S to obtain the third PWM duty cycle;

[0081] updating the stored first PWM duty cycle according to the third PWM duty cycle. ​​​

[0082] In this embodiment, the following formula is used for correction: P3=P1+K2*(S1-S), P1 is the first PWM duty ratio, and P3 is the third PWM duty ratio.

[0083] The standard starting time S is specifically obtained by:

[0084] The first PWM duty ratio is loaded to the fascia gun motor to keep the voltage at the motor winding end constant, a commutation time curve is preset in the fascia gun control module, and the fascia gun motor is started, and through debugging, it is obtained that the standard time S from static to detection of reverse electromotive force closed loop operation during smooth starting.

[0085] In one embodiment of the present application, the method for correcting the PWM duty ratio by the current voltage and the current temperature is as shown in Figure 6 , and specifically includes:

[0086] The current battery voltage is collected, the corresponding PWM duty ratio of the current battery voltage is read by referring to the pre-stored corresponding relationship between the battery voltage and the PWM duty ratio, and the PWM duty ratio is read as the second PWM duty ratio.

[0087] The current environment temperature is collected, and the corresponding PWM duty ratio is corrected according to the environment temperature, and the correction method is as follows: P2=P+K1*(T0-T), P2 is the second PWM duty ratio, and P is the corresponding PWM duty ratio.

[0088] The first PWM duty ratio is updated according to the second PWM duty ratio.

[0089] In this embodiment, the temperature correction can be performed first, and then the voltage correction.

[0090] In one embodiment of the present application, the method for correcting the PWM duty ratio by the current voltage and the starting time is as shown in Figure 7 , and specifically includes:

[0091] The current battery voltage is collected, the corresponding PWM duty ratio of the current battery voltage is read by referring to the pre-stored corresponding relationship between the battery voltage and the PWM duty ratio, and the PWM duty ratio is read as the second PWM duty ratio.

[0092] The motor starting control is performed according to the second PWM duty ratio.

[0093] The actual motor starting time S1 of this time is recorded.

[0094] The PWM duty ratio is compensated and corrected according to the actual motor starting time S1 and the standard starting time S, and the third PWM duty ratio P3 is calculated: P3=P2+K2*(S1-S), K2>0, and is a compensation correction coefficient determined by debugging, and P3 is the third PWM duty ratio.

[0095] According to the third PWM duty cycle, the stored first PWM duty cycle is updated.

[0096] In the embodiment, the standard starting time S specifically includes:

[0097] The second PWM duty cycle is loaded to the muscle fascia gun motor, so that the motor winding end maintains a constant voltage, a commutation time curve is preset in the muscle fascia gun control module, and the muscle fascia gun motor is started, and through debugging, it is obtained that the standard time S from static to detection of reverse electromotive force closed loop operation when starting smoothly.

[0098] In an embodiment of the present application, the method for correcting the PWM duty cycle by the current temperature and the starting time is as shown in Figure 8 The method specifically includes:

[0099] The current environment temperature is collected, and according to the environment temperature, the second PWM duty cycle is calculated according to the following formula:

[0100] P2=P1+K1*(T0-T), P2 is the second PWM duty cycle, P1 is the first PWM duty cycle; K1>0, and is a correction coefficient determined by testing, T0 is a threshold temperature, and T is a real-time collected environment temperature;

[0101] According to the second PWM duty cycle, the motor starting control is performed;

[0102] The actual motor starting time S1 of this time is recorded;

[0103] According to the actual motor starting time S1 and the standard starting time S, the PWM duty cycle is compensated and corrected to obtain the third PWM duty cycle: P3=P2+K2*(S1-S), K2>0, and is a compensation correction coefficient determined by debugging, and P3 is the third PWM duty cycle.

[0104] According to the third PWM duty cycle, the stored first PWM duty cycle is updated.

[0105] In the embodiment, the standard starting time S specifically includes:

[0106] The second PWM duty cycle is loaded to the muscle fascia gun motor, so that the motor winding end maintains a constant voltage, a commutation time curve is preset in the muscle fascia gun control module, and the muscle fascia gun motor is started, and through debugging, it is obtained that the standard time S from static to detection of reverse electromotive force closed loop operation when starting smoothly.

[0107] In an embodiment of the present application, the method for correcting the PWM duty cycle by the current voltage, the current temperature and the starting time is as shown in Figure 9 The method specifically includes:

[0108] In the embodiment, the electric massager is a fascia gun, and the fascia gun is powered by a battery, the time of the battery voltage applied to the motor winding is adjusted by PWM pulse width, and the speed of the motor is controlled by reducing and increasing the voltage. During the power supply process, the voltage of the battery gradually decreases as the power decreases. Therefore, in order to eliminate the influence of voltage change on the starting curve, the battery voltage is collected in real time during the test phase before formal starting, and the duty cycle required to maintain the fixed voltage at the motor winding end under different voltages is measured. The battery voltage and the PWM duty cycle form a corresponding relationship curve, as shown in Figure 1 .

[0109] The higher the battery voltage, the smaller the PWM duty cycle required, and the lower the battery voltage, the larger the PWM duty cycle required to maintain the voltage at the motor winding end unchanged. The battery voltage and PWM duty cycle curve is pre-stored in the electric massager control chip.

[0110] During the adaptive starting process, the battery voltage is collected in real time, the PWM duty cycle is read according to the curve, and the voltage applied to the motor winding is ensured unchanged. The actually measured battery voltage and PWM duty cycle curve are as shown in Figure 2 .

[0111] Because the lower the temperature, the tighter the sliding sleeve, and the greater the motor load, the starting voltage needs to be increased, and the higher the temperature, the looser the sliding sleeve, and the starting voltage needs to be reduced. Therefore, the queried PWM duty cycle is corrected by the real-time collected environmental temperature T, and the correction method is as follows:

[0112] P=P+K1*(T0-T), P is the current PWM duty cycle, K1 is the correction coefficient determined by test, T0 is the threshold temperature, and T is the real-time collected environmental temperature. The threshold temperature T0 is usually 25 degrees. If the temperature rises, the P value decreases, and if the temperature decreases, the P value increases.

[0113] Then the P value corrected by the temperature is loaded to the electric massager motor to maintain a constant voltage at the motor winding end, a commutation time curve is pre-set in the electric massager control module, and the electric massager motor is tested and started. Through debugging, the standard time S from static to detection of reverse electromotive force closed loop operation is obtained when starting smoothly.

[0114] The actual starting time S1 is recorded, and the values of the standard starting time S and the actual starting time S1 are compared. If S1>S, the PWM duty cycle is increased; if S1

[0115] Finally, the corrected compensation PWM duty ratio is stored in the electric massager control module, and the PWM duty ratio in the control module is updated. In this way, after each start, the P value is corrected, the start curve is more suitable for the electric massager, the tolerance in the manufacturing process is compensated, or the mechanical loss after long-term use of the sliding sleeve, and the user experience is improved.

[0116] In summary, the present application does not increase the hardware of the existing electric massager, and the cost is low; for different individual differences, the stored curve is updated and optimized after each start, so that the next start is more reasonable, so that the start curve can approach the reasonable interval infinitely, so that the start curve can match the changes of the electric massager hardware, such as temperature, voltage, sliding sleeve wear, etc. Greatly improve the adaptability of the electric massager start, improve the user experience.

Claims

1. An adaptive start method for the sensorless motor of an electric massager, characterized in that, include: Read the first PWM duty cycle from storage; The first PWM duty cycle is corrected to obtain the second PWM duty cycle; Motor start control is performed based on the second PWM duty cycle; The stored first PWM duty cycle is updated according to the second PWM duty cycle; The method also includes: Record the actual start-up time S1 of the motor. The PWM duty cycle is compensated and corrected based on the actual motor start time S1 and the standard start time S, and the third PWM duty cycle is calculated: P3=P2+K2*(S1-S), K2>0, and is the compensation correction coefficient determined by debugging. P2 is the second PWM duty cycle, P3 is the third PWM duty cycle, and the stored first PWM duty cycle is updated based on the third PWM duty cycle.

2. The adaptive start method for the sensorless motor of the electric massager according to claim 1, characterized in that, The step of correcting the read first PWM duty cycle to obtain the second PWM duty cycle specifically includes: The current battery voltage is collected, and the PWM duty cycle corresponding to the current battery voltage is read as the second PWM duty cycle, referring to the pre-stored correspondence between battery voltage and PWM duty cycle.

3. The adaptive start method for the sensorless motor of the electric massager according to claim 2, characterized in that, The specific methods for determining the correspondence between pre-stored battery voltage and PWM duty cycle include: During the testing phase, the battery voltage of the fascia gun is collected in real time. The PWM duty cycle required to maintain a fixed voltage at the motor winding end is measured under different battery voltages. The correspondence between battery voltage and PWM duty cycle is stored in the electric massager control module.

4. The adaptive start method for the sensorless motor of the electric massager according to claim 1, characterized in that, The step of correcting the read first PWM duty cycle to obtain the second PWM duty cycle specifically includes: Collect the current ambient temperature, and calculate the second PWM duty cycle based on the ambient temperature using the following formula: P2 = P1 + K1 * (T0 - T), where P2 is the second PWM duty cycle and P1 is the first PWM duty cycle; K1 > 0 and is a correction coefficient determined through testing; T0 is the threshold temperature and T is the ambient temperature collected in real time.

5. The adaptive start method for the sensorless motor of the electric massager according to claim 1, characterized in that, Obtaining the standard startup time S specifically includes: The second PWM duty cycle is applied to the fascia gun motor to keep the voltage at the motor winding terminals constant. At the same time, a commutation time curve is preset in the fascia gun control module, and the fascia gun motor is started. Through debugging, the standard start-up time S from standstill to detection of back electromotive force closed-loop operation is obtained during smooth start-up.

6. An adaptive start method for the sensorless motor of an electric massager, characterized in that, include: Read the first PWM duty cycle from storage; Motor start control is performed based on the first PWM duty cycle; Record the actual start-up time S1 of the motor. The first PWM duty cycle is corrected based on the actual motor start time S1 and the standard start time S to obtain the third PWM duty cycle; The stored first PWM duty cycle is updated according to the third PWM duty cycle; The correction of the first PWM duty cycle specifically includes: The correction is performed using the following formula: P3 = P1 + K2 * (S1 - S), where P1 is the duty cycle of the first PWM, P3 is the duty cycle of the third PWM, and K2 > 0, which is the compensation correction coefficient determined during debugging.

7. The adaptive start method for the sensorless motor of the electric massager according to claim 6, characterized in that, Obtaining the standard startup time S specifically includes: The first PWM duty cycle is applied to the fascia gun motor to keep the voltage at the motor winding terminals constant. At the same time, a commutation time curve is preset in the fascia gun control module, and the fascia gun motor is started. Through debugging, the standard start-up time S from standstill to detection of back electromotive force closed-loop operation is obtained during smooth start-up.

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