Handheld fan of three-phase brushless motor non-inductive foc controller

Abstract

The utility model discloses a handheld fan with a three-phase brushless motor and a non-inductive foc controller, which comprises a handle and a fan cover integrally connected with the handle, a control circuit board and a battery are arranged in the handle, an annular seat is arranged in the fan cover, a hollow mounting seat is arranged in the annular seat, a three-phase brushless motor body is mounted on the mounting seat, and the three-phase brushless motor body is connected with the fan cover. Fan blades are fixedly connected to the outer surface of a rotating shaft of the three-phase brushless motor body, the three-phase brushless motor body and the battery are both connected with the control circuit board, a control button is arranged on the handle, and the control button is in signal connection with the control circuit board; a non-inductive foc controller body and a motor rotating speed estimator are integrated on the control circuit board, a non-inductive foc closed-loop control algorithm is achieved by collecting motor phase current, a three-phase brushless motor body is driven to operate, an armature resultant magnetic field of the motor is a constant-speed continuous rotating magnetic field, phase current of an armature changes in a sinusoidal mode, and sudden change of current is avoided. When the motor operates, current noise is not generated, the efficiency reaches the optimal state when electric energy of the motor is converted into mechanical energy, and the operation efficiency of the motor is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of fans, in particular to a handheld fan with a three-phase brushless motor and a sensorless FOC controller. Background Art

[0002] Similar products currently available on the market use single-phase / three-phase brushless motors to drive the fan blades to rotate, realizing the blowing function of a portable handheld fan.

[0003] 1. Single-phase brushless motors use a boost power supply method to achieve motor operation, and use different boost voltages to achieve motor speed regulation. The boost circuit has large power loss and low battery power utilization. Most single-phase motors use magnetic rubber rotors, and the power-to-mechanical energy conversion efficiency is low. The product has a short battery life, weak wind power, and a poor user experience.

[0004] 2. The three-phase brushless motor uses a six-step square wave commutation drive solution, and the motor speed is adjusted through the PWM duty cycle. The current noise is large when the motor is running, which is annoying and the product experience is not good. Utility Model Content

[0005] The utility model aims to provide a handheld fan with a three-phase brushless motor and a sensorless FOC controller to solve the problems raised in the above background technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A handheld fan with a three-phase brushless motor and a sensorless FOC controller, comprising a handle and a fan cover connected to the handle, characterized in that the handle is equipped with a control circuit board and a battery, a ring seat is provided in the fan cover, a hollow mounting seat is provided in the ring seat, a three-phase brushless motor body is installed on the mounting seat, a fan blade is fixedly connected to the outer surface of the rotating shaft of the three-phase brushless motor body, the three-phase brushless motor body and the battery are connected to the control circuit board, a control button is provided on the handle, and the control button is connected to the control circuit board signal;

[0008] The control circuit board is integrated with a sensorless FOC controller body and a motor speed estimator.

[0009] Furthermore, the sensorless FOC controller body comprises:

[0010] foc motor magnetic field observation module, used to observe the speed of the motor when it is working at medium and high frequency;

[0011] The foc magnetic field orientation algorithm control module calculates the magnetic field orientation of the fan three-phase brushless motor body based on the fan three-phase brushless motor body speed value;

[0012] foc control module, used to control the fan three-phase brushless motor body;

[0013] The motor speed estimator includes:

[0014] Fuzzy DTC flux observer, observes the stator flux of the three-phase brushless motor;

[0015] The fuzzy PI stator resistance estimator estimates the stator resistance in real time based on the stator α-β coordinate system of the fan three-phase brushless motor body, and performs actual measurement compensation for the stator resistance changes caused by environmental factors.

[0016] Furthermore, the handle includes a front shell and a rear shell, the fan cover includes a front cover and a rear cover, the front shell and the front cover are symmetrically provided with a plurality of buckles, the rear shell and the rear cover are provided with a plurality of slots corresponding to the buckles, and the plurality of buckles pass through the slots and are connected with the rear cover.

[0017] Furthermore, a wiring groove is provided on the rear cover, one end of the wiring groove is communicated with the ring seat, and the other end of the wiring groove is communicated with the inside of the handle.

[0018] Furthermore, the rear cover is symmetrically provided with "L"-shaped fixing blocks on both sides of the lower end of the wiring slot, and a cover body corresponding to the wiring slot is placed on the fixing block, and the cover body is used to prevent the cable from tilting.

[0019] Furthermore, an undercut is provided in the handle, the undercut abuts against the end surface of the control circuit board, a plurality of fixing posts are symmetrically provided above the undercut, and a plurality of fixing holes for inserting the fixing posts are provided on the control circuit board.

[0020] Furthermore, the rotating shaft is provided with an abutment ring on the outer side of the mounting seat, and the abutment ring can abut against the fan blade.

[0021] Furthermore, a fixing groove is provided at the end of the rotating shaft, a fixing ring is provided on the fixing groove, and an end surface of the fixing ring abuts against the back surface of the rear cover.

[0022] Furthermore, the three-phase brushless motor body includes a stator and a rotor, and the stator and the rotor interact with each other magnetically.

[0023] Furthermore, the stator includes a plurality of teeth and silicon steel sheets corresponding to the teeth, a plurality of teeth are provided with tooth tops on the outside, annular magnets are provided outside the plurality of tooth tops, an annular sleeve is provided outside the annular magnet, a through hole is provided in the middle of the silicon steel sheet, a side wall of the through hole abuts against an outer wall of a mounting seat, the mounting seat is used to install a rotor, the rotor includes bearings abutted against two ends of the mounting seat, and a rotating shaft is inserted through the two bearings.

[0024] Beneficial effects of the utility model:

[0025] The utility model realizes the inductive FOC closed-loop control algorithm by collecting the motor phase current, drives the three-phase brushless motor body to operate, the armature synthetic magnetic field of the motor is a uniform and continuously rotating magnetic field, the armature phase current changes sinusoidally without current mutation, and no current noise is generated when the motor is running. At the same time, the efficiency of the motor is optimal when the electrical energy is converted into mechanical energy, and the motor operation efficiency is improved.

[0026] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : The overall structure diagram of the utility model.

[0028] Figure 2 : The internal structure diagram of the rear cover of the present utility model.

[0029] Figure 3 : The internal structure diagram of the front cover of the present utility model.

[0030] Figure 4 : Exploded view of the overall structure of the utility model.

[0031] Figure 5 : The three-phase brushless motor body structure diagram of the utility model.

[0032] Figure 6 : Explosion diagram of the three-phase brushless motor body of the utility model.

[0033] Figure 7 : Flow chart of the utility model's non-sensing FOC controller body controlling the fan rotation.

[0034] Figure numerals: 1. handle; 2. fan cover; 3. three-phase brushless motor body; 4. control circuit board; 5. battery; 6. control button; 7. fan blade; 11. front shell; 12. rear shell; 13. ring seat; 14. mounting seat; 16. abutment ring; 17. buckle; 18. slot; 19. abutment; 21. front cover; 22. rear cover; 23. cover body; 24. fixing block; 25. wiring slot; 26. fixing column; 27. undercut; 31. tooth portion; 32. silicon steel sheet; 33. tooth top; 34. ring sleeve; 35. through hole; 36. bearing; 37. rotating shaft; 38. magnet; 39. fixing ring; 41. fixing hole; 371. fixing slot. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0036] Please refer to Figure 1-7 ;

[0037] A handheld fan with a three-phase brushless motor body and a sensorless FOC controller comprises a handle 1 and a fan cover 2 connected to the handle 1. The handle 1 has a built-in control circuit board 4 and a battery 5. A ring seat 13 is provided in the fan cover 2. A hollow mounting seat 14 is provided in the ring seat 13. A three-phase brushless motor body 3 is mounted on the mounting seat 14. The three-phase DC brushless motor in this embodiment is a reference (high-speed BLDC motor). A fan blade 7 is fixedly connected to the outer surface of the rotating shaft 37 of the three-phase brushless motor body 3. The three-phase brushless motor body 3 and the battery 5 are both connected to the control circuit board 4. The control circuit board 4 predicts the magnetic field position of the motor through an algorithm, thereby accurately controlling the speed and torque of the motor without a position sensor. This prediction enables the controller to accurately control the speed and torque of the motor, thereby achieving efficient and smooth operation. At the same time, The control circuit board 4 can detect the status of the battery 5 and adjust the operation mode of the fan according to the power of the battery 5, which not only prolongs the service life of the battery 5, but also ensures that the fan can still operate efficiently when the battery 5 is low in power. A control button 6 is provided on the handle 1, and the control button 6 is connected to the control circuit board 4 signal. The control button 6 has the function of controlling the start and stop and speed regulation of the fan. The inductive FOC closed-loop control algorithm is realized by collecting the motor phase current to drive the three-phase brushless motor body 3 to operate. The armature synthetic magnetic field of the motor is a uniform and continuously rotating magnetic field. The phase current of the armature changes sinusoidally without current mutation. No current noise is generated when the motor is running. At the same time, the efficiency of the motor is optimal when the electrical energy is converted into mechanical energy, and the motor operation efficiency is improved. The control circuit board 4 is integrated with a inductive FOC controller body and a motor speed estimator.

[0038] The sensorless FOC controller body in this embodiment includes:

[0039] foc motor magnetic field observation module, used to observe the speed of the motor when it is working at medium and high frequency;

[0040] The foc magnetic field orientation algorithm control module calculates the magnetic field orientation of the fan three-phase brushless motor body 3 based on the rotation speed value of the fan three-phase brushless motor body 3;

[0041] The foc control module is used to control the fan three-phase brushless motor body 3;

[0042] The motor speed estimator includes:

[0043] Fuzzy DTC flux observer, observes the stator flux of the three-phase brushless motor body;

[0044] The fuzzy PI stator resistance estimator estimates the stator resistance in real time based on the stator α-β coordinate system of the fan three-phase brushless motor body 3, and performs measured compensation for the stator resistance change caused by environmental factors, referring to the Chinese patent document "CN116345976A, an algorithm and system for realizing low-frequency control of a brushless motor with sensorless FOC".

[0045] In this embodiment, the handle 1 includes a front shell 11 and a rear shell 12, and the fan cover 2 includes a front cover 21 and a rear cover 22. A plurality of buckles 17 are symmetrically provided on the front shell 11 and the front cover 21, and a plurality of slots 18 corresponding to the buckles 17 are provided on the rear shell 12 and the rear cover 22. A plurality of buckles 17 pass through the slots 18 and are engaged with the rear cover 22, thereby firmly fixing the front cover 21 and the rear cover 22, and the front shell 11 and the rear shell 12 together.

[0046] In this embodiment, a wiring groove 25 is provided on the rear cover 22. One end of the wiring groove 25 is communicated with the ring seat 13, and the other end is communicated with the inside of the handle 1. The wiring groove 25 is used as a passage for the cable.

[0047] Furthermore, the rear cover 22 is symmetrically provided with "L"-shaped fixing blocks 24 on both sides of the lower end of the wiring slot 25, and a cover body 23 corresponding to the shape of the wiring slot 25 is placed on the fixing block 24. The cover body 23 is used to prevent the cable from curling up, so that the cable can be hidden through the wiring slot 25. It can not only increase the cleanliness of the entire fan interior, but also avoid the cable from accidentally touching the fan blades 7 when the cable is tilted when rotating to cause damage.

[0048] In this embodiment, an undercut 27 is provided in the handle 1, and an abutment member 19 is provided on the side opposite to the undercut 27. The abutment member 19 and the undercut 27 abut against the same end surface of the control circuit board 4. A plurality of fixing columns 26 are symmetrically provided above the undercut 27, and a plurality of fixing holes 41 for inserting the fixing columns 26 are provided on the control circuit board 4. Specifically, the abutment member 19 and the undercut 27 abut against the same end surface of the control circuit board 4, thereby ensuring that the control circuit board 4 will not separate from the fixing columns 26.

[0049] In this embodiment, the rotating shaft 37 is located on the outer side of the mounting seat 14 and is provided with an abutment ring 16, which can abut against the fan blades 7. Since the fan blades 7 will shake when rotating, the rotating shaft 37 will drive the fan blades 7 to move relatively when shaking, so that the fan blades 7 may contact the end surface of the mounting seat 14 and cause wear. By providing the abutment ring 16, direct contact between the mounting seat 14 and the fan blades 7 can be effectively avoided, which can effectively reduce the wear of the fan blades 7 on the end surface of the mounting seat 14 and improve the service life of the fan. In addition, the abutment ring 16 in this embodiment preferably adopts a donut-like shape to minimize the contact area between the fan blades 7 and the abutment ring 16, effectively reducing the kinetic energy loss when the fan blades 7 abut against the abutment member 19 during rotation, thereby improving the stability of the fan during rotation.

[0050] In this embodiment, a fixing groove 371 is provided at the end of the rotating shaft 37, and a fixing ring 39 is provided on the fixing groove 371. The end surface of the fixing ring 39 abuts against the back surface of the rear cover 22 to prevent the rotating shaft 37 from falling off and improve the stability of use.

[0051] In this embodiment, the three-phase brushless motor body 3 includes a stator and a rotor. The stator and the rotor interact magnetically to make the rotor rotate.

[0052] Specifically, the stator includes a plurality of teeth 31 and silicon steel sheets 32 corresponding to the teeth 31. The teeth 31 are wound with enameled wire packages, which form magnetic lines of force when energized. For example, two enameled wire packages form a group of enameled wire packages, which form a magnetic line of force loop when energized. The silicon steel sheets 32 are mainly used to reduce magnetic resistance and participate in magnetic circuit operation. A plurality of teeth 31 are provided with tooth tops 33 on the outside, and annular magnets 38 are provided on the outside of the plurality of tooth tops 33. A ring sleeve 34 is provided on the outside of the annular magnet 38. A through hole 35 is provided in the middle of the silicon steel sheet 32. The side wall of the through hole 35 abuts against the outer wall of the mounting seat 14. The mounting seat 14 is used to install a rotor. The rotor includes bearings 36 abutting against both ends of the mounting seat 14. A rotating shaft 37 is inserted into the two bearings 36. Specifically, the enameled wire package serves as a current-carrying conductor of the coil winding. Through the alternating frequency and waveform of the current, a magnetic field is formed around the stator to drive the rotor to rotate, thereby driving the three-phase brushless motor body 3 to rotate.

[0053] The method for controlling the rotation of a fan based on a sensorless FOC controller body includes:

[0054] S1, start state, the user starts the fan by pressing the control button 6, and the control circuit board 4 enters the initialization state after receiving the start signal, and analyzes the received signal to determine the position of the motor;

[0055] S2, the control circuit board 4 performs a self-check to confirm that the power supply, the motor and the controller are in good condition and have no faults, analyzes the collected phase current signals, determines the position and speed of the motor, and adjusts the motor drive signal in real time to ensure that the armature synthetic magnetic field rotates evenly;

[0056] S3, the controller sends a start command to the three-phase brushless motor body 3 to drive the three-phase brushless motor body 3 to run, the motor starts to run at a preset low speed, and controls the circuit board 4 to adjust the motor speed according to the wind speed set by the user. In this process, the foc controller detects the current and voltage of the motor in real time, and can accurately control it without a position sensor;

[0057] S4, after the motor reaches the required speed, the control circuit board 4 ensures that the motor runs stably at the speed while optimizing energy consumption. At this time, the user can adjust the wind speed at any time through the control button 6, and the control circuit board 4 will respond to the user's input and adjust the motor speed in real time;

[0058] S5, the user presses the control button 6, the control circuit board 4 receives the stop signal, instructs the motor to gradually decelerate until it stops, and cuts off the power supply.

[0059] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0060] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims

1. A handheld fan with a three-phase brushless motor and a sensorless FOC controller, comprising a handle (1) and a fan cover (2) integrally connected to the handle (1), characterized in that: The handle (1) is provided with a control circuit board (4) and a battery (5); a ring seat (13) is provided in the fan cover (2); a hollow mounting seat (14) is provided in the ring seat (13); a three-phase brushless motor body (3) is mounted on the mounting seat (14); a fan blade (7) is fixedly connected to the outer surface of the rotating shaft (37) of the three-phase brushless motor body (3); the three-phase brushless motor body (3) and the battery (5) are both connected to the control circuit board (4); a control button (6) is provided on the handle (1); and the control button (6) is connected to the control circuit board (4) by signal. The control circuit board (4) is integrated with a sensorless FOC controller body and a motor speed estimator.

2. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: The sensorless FOC controller body comprises: foc motor magnetic field observation module, used to observe the speed of the motor when it is working at medium and high frequency; A foc magnetic field orientation algorithm control module calculates the magnetic field orientation of the fan three-phase brushless motor body (3) based on the rotation speed value of the fan three-phase brushless motor body (3); A foc control module, used to control a fan three-phase brushless motor body (3); The motor speed estimator includes: A fuzzy DTC flux observer observes the stator flux of the three-phase brushless motor body (3); The fuzzy PI stator resistance estimator estimates the stator resistance in real time based on the stator α-β coordinate system of the fan three-phase brushless motor body (3), and performs actual measurement compensation for the stator resistance change caused by environmental factors.

3. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: The handle (1) comprises a front shell (11) and a rear shell (12); the fan cover (2) comprises a front cover (21) and a rear cover (22); the front shell (11) and the front cover (21) are symmetrically provided with a plurality of buckles (17); the rear shell (12) and the rear cover (22) are provided with a plurality of slots (18) corresponding to the buckles (17); and the plurality of buckles (17) pass through the slots (18) and are engaged with the rear cover (22).

4. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 3, characterized in that: The rear cover (22) is provided with a wiring groove (25), one end of which is communicated with the ring seat (13), and the other end of which is communicated with the inside of the handle (1).

5. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 4, characterized in that: The rear cover (22) is symmetrically provided with "L"-shaped fixing blocks (24) on both sides of the lower end of the wiring slot (25), and a cover body (23) corresponding to the wiring slot (25) is placed on the fixing block (24), and the cover body (23) is used to prevent the cable from tilting.

6. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: An undercut (27) is provided in the handle (1), and a contact piece (19) is provided on a side opposite to the undercut (27). The contact piece (19) and the undercut (27) are both in contact with the same end surface of the control circuit board (4). A plurality of fixing posts (26) are symmetrically provided above the undercut (27), and a plurality of fixing holes (41) for inserting the fixing posts (26) are provided on the control circuit board (4).

7. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: The rotating shaft (37) is provided with an abutment ring (16) on the outer side of the mounting seat (14), and the abutment ring (16) can abut against the fan blade (7).

8. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: A fixing groove (371) is provided at the end of the rotating shaft (37), a fixing ring (39) is provided on the fixing groove (371), and the end surface of the fixing ring (39) abuts against the back surface of the rear cover (22).

9. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 1, characterized in that: The three-phase brushless motor body (3) comprises a stator and a rotor, and the stator and the rotor interact with each other magnetically.

10. A handheld fan with a three-phase brushless motor and a sensorless FOC controller according to claim 9, characterized in that: The stator comprises a plurality of tooth portions (31) and silicon steel sheets (32) corresponding to the tooth portions (31); tooth top portions (33) are arranged outside the plurality of tooth top portions (33); annular magnets (38) are arranged outside the plurality of tooth top portions (33); a ring sleeve (34) is arranged outside the annular magnet (38); a through hole (35) is arranged in the middle of the silicon steel sheet (32); a side wall of the through hole (35) abuts against an outer wall of a mounting seat (14); a rotor is mounted inside the mounting seat (14); the rotor comprises bearings (36) abutting against two ends of the mounting seat (14); a rotating shaft (37) is inserted through two of the bearings (36).

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