JP3196982U - Brushless DC motor rotation speed control device - Google Patents

Abstract

A rotational speed control system for a brushless DC motor capable of responding to changes in rotational speed in a very wide range is provided. A rotational speed control system for a brushless DC motor includes a brushless DC motor, at least one Hall sensor component, an inverter circuit, a gate drive circuit, and a microcontroller. Rotational speed control that outputs high torque during low-speed operation through a system that drives two stator coil circuits alternately, and outputs low torque during high-speed operation through a system that drives any stator coil circuit Achieve effect. As a result, the motor operation can be started without using a high-output power source, and when the motor operation reaches the set rotational speed, the operation of the system that drives the coil circuit of any stator Can be switched. [Selection] Figure 1

Description

  The present invention relates to a motor rotation speed control technology, and relates to a rotation speed control system for a brushless DC motor that can output high torque during low-speed operation and can output low torque during high-speed operation.

A motor (also called an electric motor) converts electric power into mechanical energy and drives the machine to rotate, vibrate, or linearly move.
In addition to being widely used in the fields of automatic control and electric devices, motors are used in many home appliances in daily life.
As a result, the types and operations of motors are becoming increasingly diverse.

There are many types of motors, and they are roughly classified into DC motors and AC motors depending on the drive current.
The basic structure is composed of a stator and a rotor.

AC motors have a simple structure and are inexpensive, but once they were relatively difficult to control speed changes, they have been mainly applied to constant rotation speeds or multi-stage speed changes.
Since the rotational speed of the AC motor is actually proportional to the frequency of the supplied current during actual operation, in principle, the higher the frequency, the faster the rotational speed.
Due to the fact that inverters have been applied to AC motor speed change control, and it has already been a considerable time in the industry, and the development of power electronic components due to the rapid development of large-scale IC circuits in recent years, complicated control has become possible. It is realized by software based on a microprocessor.

In general, a rotor of a DC motor is an electromagnet (configured by winding an enamel wire), and a stator is a permanent magnet.
A permanent magnet constitutes a magnetic field, and an electromagnetic magnet wound with a coil constitutes a rotor.
By changing the direction of the current in a timely manner, the rotor rotates continuously in the same direction.

For example, a brush direct current motor rotates an armature by causing an electric current to flow through an electric brush, and a plurality of lines are wound around a rotor by a generated vertical magnetic field to adjust an electric brush and a commutator. Through the current flowing into the armature, the rotor magnetic field is controlled and the vertical direction in the magnetic field is maintained.

On the other hand, the brushless DC motor can solve the maintenance problem of the electric brush and commutator of the brush DC motor.
The biggest difference in the principle of operation between the brush type DC motor and the brush type DC motor is that the brushless DC motor is changed to electronic rectification to achieve the purpose of maintaining the rotor and the stator magnetic field at a predetermined phase difference.

When adjusting the rotational speed of a conventional brushless DC motor, it can be achieved by varying the voltage, which is seemingly simple and easy.
However, when the motor is heavily loaded, a serious torque shortage problem occurs.
For this reason, the motor cannot be started and operated from the suspended state unless a power source with high power is selected.
This not only restricts the power source used for the brushless DC motor, but also consumes more power during the full-time operation of the brushless DC motor.

Taiwan patent TWI353705 Taiwan patent TWI411198

  However, the above-described device has drawbacks in use and needs to be improved. The cause is as follows.

When adjusting the rotational speed of a conventional brushless DC motor, if a large load is applied to the motor, a serious problem of insufficient torque occurs. And cannot be driven.
This not only restricts the power source used for the brushless DC motor, but also consumes more power during the full-time operation of the brushless DC motor.

  The present invention has been made in view of the above-mentioned problems, and the purpose of the present invention is to provide a rotational speed of a brushless DC motor that can output high torque during low-speed operation of the applied brushless DC motor and can output low torque during high-speed operation. To provide a control system.

The rotational speed control system for a brushless DC motor according to the present invention includes at least a brushless DC motor, an inverter circuit, a gate drive circuit, and a microcontroller.
A brushless DC motor has two stators and one rotor.
Two stators are arranged and installed along a homologous axis.
Each stator includes a main body having an annular shape.
On the main body, a stator tooth extending to the center of the main body is installed.
A tip is installed at each stator tooth end.
A coil having a predetermined number of gates is wound around each stator tooth.
In addition, the two stator chips intersect and surround each other to form a circular hole structure.
The rotor is installed relative to each other in the shape of a circular structure of two stators.
The rotor is installed on the shaft so as to surround a plurality of permanent magnets.
In addition, all the permanent magnets are arranged and installed in such a manner that N poles / S poles cross each other on the outer periphery of the shaft.

The inverter circuit is electrically connected between the two stators of the brushless DC motor and the DC power source.
The gate drive circuit constitutes an electrical connection between the microcontroller and the inverter circuit.
A microcontroller connects to an external speed control signal.

Utilizing the technical features described above, the rotational speed control system of the brushless DC motor of the present invention configures an electrical connection between two stators and a DC power source through an inverter circuit when in use.
In addition, it corresponds to the integrated operation of the microcontroller and the gate drive circuit, and based on the received rotation speed control signal and the signal transmitted by the hall sensor component, the two stator coil circuits are driven alternately, or any The stator coil circuit is driven to form an interacting electromagnetic field in the energized stator and rotor.
Thus, the rotor rotates continuously in the same direction.
As a result, high torque can be output during low-speed operation through a system that alternately drives two stator coil circuits, and low torque can be output during high-speed operation through a system that drives any stator coil circuit. Achieve rotational speed control effect.
Based on the technical features described above, the rotational speed control system of the brushless DC motor has at least one Hall sensor component installed around the rotor of the brushless DC motor, and responds to changes in the permanent magnet position of the rotor. Generate a current signal.
Based on the above technical features, the inverter circuit employs a series or parallel connection method and is electrically connected.
Based on the above technical features, the range of the gap between adjacent chips is 2 mm to 5 mm.
Based on the above technical features, each stator tooth has an electrical angle (180 degrees / m) between adjacent coils. m is the number of stators.
Based on the above technical features, at least one Hall sensor component is installed around the rotor of the brushless DC motor, and is electrically connected to the microcontroller, and the rotational speed of the rotor is detected by the Hall sensor component.
Based on the above technical features, at least two hall sensor parts are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller. And the timing of current exchange is detected by another Hall sensor component.
Based on the above technical features, at least three hall sensor parts are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller. , Detect the current exchange timing with another Hall sensor component, and detect and determine the rotation direction of the rotor with another Hall sensor component.
Based on the above technical features, the microcontroller connects the external rotational speed control signal and the current signal of at least one Hall sensor component, and based on the received rotational speed control signal and the signal transmitted by the Hall sensor component. The gate electrode is controlled to drive the circuit, and the two stator coil circuits are driven alternately.

Based on the above technical features, the microcontroller connects the external rotational speed control signal and the current signal of at least one Hall sensor component, and based on the received rotational speed control signal and the signal transmitted by the Hall sensor component. The coil circuit of an arbitrary stator is driven, whereby the energized stator and the corresponding rotor form an interacting electromagnetic field.
Each stator is provided with 8 stator teeth, and each rotor is provided with 8 permanent magnets.
Each stator is provided with an even number of stator teeth, and the rotor is provided with an even number of permanent magnets.
Each stator is provided with an even number of stator teeth, and the rotor is provided with an even number of permanent magnets corresponding to the stator.
Each stator is formed by stacking a plurality of pieces of silicon steel having a homologous structure.
The length of each permanent magnet in the axial direction includes the installation range of the two stator chips.

The brushless DC motor rotational speed control system of the present invention outputs a high torque during low-speed operation through a method of alternately driving two stator coil circuits, and a system for driving an arbitrary stator coil circuit. Through this, low torque can be output during high-speed operation, motor operation can be started without using a high-output power supply, and when the motor operation reaches the set rotation speed, any stator coil The operation is switched to a system that drives the circuit, so that the restriction on the power source for using the brushless DC motor can be lowered, and the power saving effect is provided in the full-time operation process of the brushless DC motor.

1 is a schematic diagram of a configuration of a rotational speed control system for a brushless DC motor according to the present invention. It is a three-dimensional external view of the brushless DC motor of the present invention. 1 is an exploded view of a brushless DC motor according to the present invention. 1 is a structural cross-sectional view of a brushless DC motor of the present invention. In the brushless direct current motor of the present invention, when driving by the method of alternately driving the coil circuit of two stators, it is a schematic diagram showing the magnetic interaction relationship between the stator and the rotor. In the brushless DC motor of the present invention, it is a schematic diagram showing the magnetic interaction relationship between the stator and the rotor when it is operated by a method of driving a coil circuit of an arbitrary stator.

(One embodiment)
A rotational speed control system for a brushless DC motor according to an embodiment of the present invention is a rotational speed control system for a brushless DC motor that can output high torque during low speed operation and can output low torque during high speed operation. The rotational speed control effect of outputting high torque and low torque during high speed operation can be achieved, and it is possible to cope with a very wide range of rotational speed changes.

A rotational speed control system for a brushless DC motor according to an embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, which is a schematic diagram of the configuration of a rotational speed control system for a brushless DC motor according to the present invention, the rotational speed control system for a brushless DC motor according to the present invention comprises one brushless DC motor 20, at least one Hall sensor component. 11, an inverter circuit 12, a gate drive circuit 13, and a microcontroller 14.

As shown in FIGS. 1 to 5, the brushless DC motor 20 is provided with two stators 21 and one rotor 22.
The two stators 21 are arranged and installed along a homologous axis.
Each stator 21 includes a main body 211 having an annular shape.
On the main body 211, stator teeth 212 extending toward the center of the main body 211 are installed.
A tip 213 is installed at the end of each stator tooth 212.
A coil 214 having a predetermined number of gates is wound and installed on each stator tooth 213.

The gap between each stator 21 and the adjacent chip 213 is 2 mm to 5 mm. If the gap is smaller than 2 mm, winding is difficult. If the gap is larger than 5 mm, unnecessary magnetic force is easily generated and the cost is high.
In addition, the chips 213 of the two stators 21 intersect and surround each other and have a circular hole-like structure form.

The rotor 22 is installed relative to the circular hole structure of the two stators 21.
The rotor 22 is installed on the shaft 221 so as to surround the plurality of permanent magnets 222.
Moreover, all the permanent magnets 222 are arranged and installed on the outer periphery of the shaft 221 in such a manner that the N poles / S poles are arranged so as to intersect each other.

Each stator tooth 212 has an electrical angle of 180 ° / m between the adjacent coils 214. m is the number of stators.
Here, there is no doubt that the relationship between the mechanical angle and the electrical angle is determined by the number of stators.
Each stator tooth 212 has an electrical angle of 180 ° / m between each adjacent coil. m is the number of stators.
Therefore, one cycle of electrical angles does not correspond to one cycle of mechanical angles.
In the embodiment of the present invention, two stators 21 are taken as an example, each stator 21 has eight stator teeth 212, and one period of the electrical angle is 1/4 of the rotation angle of the rotor 22. It corresponds to.
At this time, even if the electrical angle is a sensing voltage in a certain angle, it changes to a sensing voltage detected at a different mechanical angle.
If the mechanical angles are different, a change occurs in the sensed voltage based on the mechanical structure of the number of stators 21.

At least one Hall sensor component 11 is installed in the vicinity of the rotor 22 of the brushless DC motor 20.
Thus, a corresponding current signal is generated in accordance with the change in the position of the permanent magnet 222 of the rotor 22.
In the present embodiment, three Hall sensor components 11 that are electrically connected to the microcontroller 14 are installed around the rotor 22 of the brushless DC motor 20.
One Hall sensor component senses the rotational speed of the rotor, one Hall sensor component senses the timing of current exchange, and one Hall sensor component senses and determines the rotational direction of the rotor. .

The inverter circuit 12 is electrically connected between the two stators 21 of the brushless DC motor 20 and the DC power supply.
The inverter circuit 12 is composed of at least four electronic components.
Each electronic component is electrically connected to constitute the inverter circuit 12.
In the embodiment of the present invention, there are eight electronic components.
The inverter circuit 12 employs a series or parallel connection method and is electrically connected.

The gate drive circuit 13 constitutes an electrical connection between the microcontroller 14 and the inverter circuit 12.
The microcontroller 14 is connected to the external rotation speed control signal and the current signal of at least one Hall sensor component 11.
The electronic component is a transistor.

As shown in the embodiment of FIGS. 1 and 2, the inverter circuit 12 includes eight transistors Q1 to Q8.
The transistors Q1 to Q4 are connected to a single stator coil circuit.
The transistors Q5 to Q8 are connected to another stator coil circuit.
The gate drive circuit 13 is connected to the transistors Q1 to Q8, respectively.
Thereby, the open or shut-off of the transistors Q1 to Q8 is controlled.

In addition, the gate drive circuit 13 is controlled based on the received rotation speed control signal and the signal fed back to the microcontroller 14 by the hall sensor component 11 to transmit the signal to the inverter circuit 12.
The inverter circuit 12 simultaneously activates a plurality of electronic components, switches the electromagnetic field of the corresponding electronic components, and forms an N pole / S pole intersection.
As a result, the coil circuits of the two stators 21 are simultaneously activated and alternately driven, and the gate drive circuit 13 controls the open or shut-off of the transistors Q1 to Q8.
As a result, the coil circuits of the two stators 21 are alternately energized.

Alternatively, the gate drive circuit 13 is controlled based on the received rotation speed control signal and the signal fed back to the microcontroller 14 by the hall sensor component 11 to transmit the signal to the inverter circuit 12.
The inverter circuit 12 drives only some electronic components and switches to electronic components that affect any stator.
In this way, the coil circuit of the arbitrary stator 21 is driven, and the energized stator 21 and the corresponding rotor 22 form an interaction electromagnetic field, and the gate drive circuit 13 controls the open or shut-off of the transistors Q1 to Q8. To do.
Thereby, the coil circuit of the arbitrary stator 21 is single-phase energized.

In principle, the rotational speed control system for a brushless DC motor according to the present invention constitutes an electrical connection between the two stators 21 and the DC power source through the inverter circuit 12 when in use.
Moreover, it corresponds to the integrated operation of the microcontroller 14 and the gate drive circuit 13, and based on the received rotational speed control signal and the signal transmitted by the hall sensor component 11, the coil circuit of the two stators 21 (see FIG. 5). Are alternately driven or a coil circuit (see FIG. 6) of an arbitrary stator 21 is driven to form an interacting electromagnetic field in the energized stator 21 and rotor 22.
Thus, the rotor 22 rotates continuously in the same direction.

In the above embodiment, the rotor position of the motor is sensed and detected using the hall sensor component, and the rotor position of the motor is sensed and detected using another sensor.

That is, the brushless DC motor system of the present invention does not require a high-output power source, and can operate the brushless DC motor to be applied by starting it from a stopped state.
Moreover, after the operation to the set rotational speed, the operation can be switched to the operation in which the coil circuit of an arbitrary stator is driven.
As a result, the restriction on the power source for using the brushless DC motor can be reduced, and a power saving effect can be provided in the full-time operation process of the brushless DC motor.

Furthermore, when implementing the brushless DC motor 20 to which the present invention is applied, a plurality of silicon steel pieces having the same structural form as the stators 21 are overlapped to constitute each.
In the present embodiment, eight stator teeth 212 are installed on each stator 21, and eight permanent magnets 222 are installed on the rotor 22.
Moreover, the length of each permanent magnet 222 in the axial direction preferably includes the installation range of the chips 213 of the two stators 21.

Naturally, each stator 21 can be provided with an even number of stator teeth, and each rotor 22 can be provided with an even number of permanent magnets 222.
For example, the eight stator teeth 212 correspond to the four permanent magnets 222, or each stator 21 is provided with an even number of stator teeth 212, and the rotor 22 is connected to the stator 21. A corresponding even number of permanent magnets 222 are installed.

The brushless DC motor to which the present invention is applied should be designed with different numbers of stator teeth and rotor permanent magnets for each stator depending on the actual size. Can do.
In addition, the coil rectification timing of each stator can be effectively controlled by the corresponding operation of the appropriate drive circuit, and the operation efficiency of the entire brushless DC motor can be easily improved, or the range of change in the rotational speed can be expanded. it can.

Compared with the prior art, the rotational speed control system of the brushless DC motor of the present invention outputs a high torque during low-speed operation through a method of alternately driving the coil circuits of two stators, and an arbitrary stator. Low torque can be output during high-speed operation through the method of driving the coil circuit.
The rotation speed control method can start the motor operation without using a high-output power source.

Moreover, after the motor operation reaches the set rotational speed, it can be switched to the operation with the method of driving the coil circuit of any stator, which not only reduces the limitation of the power supply for using the brushless DC motor, Power saving effect is provided in the full-time operation process of brushless DC motor.
Thus, the brushless motor control system can achieve a rotational speed control effect that outputs high torque during low-speed operation and low torque during high-speed operation, and can cope with a very wide range of rotational speed changes.

  By summing up the descriptions of the above embodiments, the operation, use, and effects of the present invention can be fully understood. However, the embodiment described above is merely a preferred embodiment of the present invention, and is not intended to limit the scope of the utility model registration claim of the present invention. That is, all simple changes and modifications having the same effect based on the scope of the claims of the utility model registration of the present invention and the contents of the description shall fall within the scope of the present invention.

Q1 to Q8 Transistor 11 Hall sensor component 12 Inverter circuit 13 Gate drive circuit 14 Microcontroller 20 Brushless DC motor 21 Stator 211 Main body 212 Stator teeth 213 Chip 214 Coil 22 Rotor 221 Shaft 222 Permanent magnet

The present invention relates to a motor rotation speed control technique, and more particularly to a rotation speed control device for a brushless DC motor that can output high torque during low-speed operation and can output low torque during high-speed operation.

A motor (also called an electric motor) converts electric power into mechanical energy and drives the machine to rotate, vibrate, or linearly move.
In addition to being widely used in the fields of automatic control and electric devices, motors are used in many home appliances in daily life.
As a result, the types and operations of motors are becoming increasingly diverse.

There are many types of motors, and they are roughly classified into DC motors and AC motors depending on the drive current.
The basic structure is composed of a stator and a rotor.

AC motors have a simple structure and are inexpensive, but once they were relatively difficult to control speed changes, they have been mainly applied to constant rotation speeds or multi-stage speed changes.
Since the rotational speed of the AC motor is actually proportional to the frequency of the supplied current during actual operation, in principle, the higher the frequency, the faster the rotational speed.
Due to the fact that inverters have been applied to AC motor speed change control, and it has already been a considerable time in the industry, and the development of power electronic components due to the rapid development of large-scale IC circuits in recent years, complicated control has become possible. It is realized by software based on a microprocessor.

In general, a rotor of a DC motor is an electromagnet (configured by winding an enamel wire), and a stator is a permanent magnet.
A permanent magnet constitutes a magnetic field, and an electromagnetic magnet wound with a coil constitutes a rotor.
By changing the direction of the current in a timely manner, the rotor rotates continuously in the same direction.

For example, a brush direct current motor rotates an armature by causing an electric current to flow through an electric brush, and a plurality of lines are wound around a rotor by a generated vertical magnetic field to adjust an electric brush and a commutator. Through the current flowing into the armature, the rotor magnetic field is controlled and the vertical direction in the magnetic field is maintained.

On the other hand, the brushless DC motor can solve the maintenance problem of the electric brush and commutator of the brush DC motor.
The biggest difference in the principle of operation between the brush type DC motor and the brush type DC motor is that the brushless DC motor is changed to electronic rectification to achieve the purpose of maintaining the rotor and the stator magnetic field at a predetermined phase difference.

When adjusting the rotational speed of a conventional brushless DC motor, it can be achieved by varying the voltage, which is seemingly simple and easy.
However, when the motor is heavily loaded, a serious torque shortage problem occurs.
For this reason, the motor cannot be started and operated from the suspended state unless a power source with high power is selected.
This not only restricts the power source used for the brushless DC motor, but also consumes more power during the full-time operation of the brushless DC motor.

Taiwan patent TWI353705 Taiwan patent TWI411198

  However, the above-described device has drawbacks in use and needs to be improved. The cause is as follows.

When adjusting the rotational speed of a conventional brushless DC motor, if a large load is applied to the motor, a serious problem of insufficient torque occurs. And cannot be driven.
This not only restricts the power source used for the brushless DC motor, but also consumes more power during the full-time operation of the brushless DC motor.

The present invention has been made in view of the above-mentioned problems, and the purpose of the present invention is to provide a rotational speed of a brushless DC motor that can output high torque during low-speed operation of the applied brushless DC motor and can output low torque during high-speed operation. It is to provide a control device .

A brushless DC motor rotation speed control device according to the present invention includes at least a brushless DC motor, an inverter circuit, a gate drive circuit, and a microcontroller.
A brushless DC motor has two stators and one rotor.
Two stators are arranged and installed along a homologous axis.
Each stator includes a main body having an annular shape.
On the main body, a stator tooth extending to the center of the main body is installed.
A tip is installed at each stator tooth end.
A coil having a predetermined number of gates is wound around each stator tooth.
In addition, the two stator chips intersect and surround each other to form a circular hole structure.
The rotor is installed relative to each other in the shape of a circular structure of two stators.
The rotor is installed on the shaft so as to surround a plurality of permanent magnets.
In addition, all the permanent magnets are arranged and installed in such a manner that N poles / S poles cross each other on the outer periphery of the shaft.

The inverter circuit is electrically connected between the two stators of the brushless DC motor and the DC power source.
The gate drive circuit constitutes an electrical connection between the microcontroller and the inverter circuit.
A microcontroller connects to an external speed control signal.

Utilizing the technical features described above, the rotational speed control device for a brushless DC motor of the present invention constitutes an electrical connection between two stators and a DC power source through an inverter circuit when in use.
In addition, it corresponds to the integrated operation of the microcontroller and the gate drive circuit, and based on the received rotation speed control signal and the signal transmitted by the hall sensor component, the two stator coil circuits are driven alternately, or any The stator coil circuit is driven to form an interacting electromagnetic field in the energized stator and rotor.
Thus, the rotor rotates continuously in the same direction.
As a result, high torque can be output during low-speed operation through a system that alternately drives two stator coil circuits, and low torque can be output during high-speed operation through a system that drives any stator coil circuit. Achieve rotational speed control effect.
Based on the technical features described above, the brushless DC motor rotational speed control device has at least one Hall sensor component installed around the rotor of the brushless DC motor, and responds to changes in the permanent magnet position of the rotor. Generate a current signal.
Based on the above technical features, the inverter circuit employs a series or parallel connection method and is electrically connected.
Based on the above technical features, the range of the gap between adjacent chips is 2 mm to 5 mm.
Based on the above technical features, each stator tooth has an electrical angle (180 degrees / m) between adjacent coils. m is the number of stators.
Based on the above technical features, at least one Hall sensor component is installed around the rotor of the brushless DC motor, and is electrically connected to the microcontroller, and the rotational speed of the rotor is detected by the Hall sensor component.
Based on the above technical features, at least two hall sensor parts are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller. And the timing of current exchange is detected by another Hall sensor component.
Based on the above technical features, at least three hall sensor parts are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller. , Detect the current exchange timing with another Hall sensor component, and detect and determine the rotation direction of the rotor with another Hall sensor component.
Based on the above technical features, the microcontroller connects the external rotational speed control signal and the current signal of at least one Hall sensor component, and based on the received rotational speed control signal and the signal transmitted by the Hall sensor component. Then, the gate drive circuit is controlled to drive the two stator coil circuits alternately.

Based on the above technical features, the microcontroller connects the external rotational speed control signal and the current signal of at least one Hall sensor component, and based on the received rotational speed control signal and the signal transmitted by the Hall sensor component. The coil circuit of an arbitrary stator is driven, whereby the energized stator and the corresponding rotor form an interacting electromagnetic field.
Each stator is provided with 8 stator teeth, and each rotor is provided with 8 permanent magnets.
Each stator is provided with an even number of stator teeth, and the rotor is provided with an even number of permanent magnets.
Each stator is provided with an even number of stator teeth, and the rotor is provided with an even number of permanent magnets corresponding to the stator.
Each stator is formed by stacking a plurality of pieces of silicon steel having a homologous structure.
The length of each permanent magnet in the axial direction includes the installation range of the two stator chips.

The rotational speed control device for a brushless DC motor according to the present invention is a system that outputs a high torque during low-speed operation and drives an arbitrary stator coil circuit through a system that alternately drives two stator coil circuits. Through this, low torque can be output during high-speed operation, motor operation can be started without using a high-output power supply, and when the motor operation reaches the set rotation speed, any stator coil The operation is switched to a system that drives the circuit, so that the restriction on the power source for using the brushless DC motor can be lowered, and the power saving effect is provided in the full-time operation process of the brushless DC motor.

1 is a schematic diagram of a configuration of a rotational speed control device for a brushless DC motor according to the present invention. It is a three-dimensional external view of the brushless DC motor of the present invention. 1 is an exploded view of a brushless DC motor according to the present invention. 1 is a structural cross-sectional view of a brushless DC motor of the present invention. In the brushless direct current motor of the present invention, when driving by the method of alternately driving the coil circuit of two stators, it is a schematic diagram showing the magnetic interaction relationship between the stator and the rotor. In the brushless DC motor of the present invention, it is a schematic diagram showing the magnetic interaction relationship between the stator and the rotor when it is operated by a method of driving a coil circuit of an arbitrary stator.

(One embodiment)
Rotational speed control device for a brushless DC motor according to an embodiment of the present invention is a high torque can be output at the time of low speed operation, and a speed control device for a brushless DC motor capable of outputting a low torque during high-speed operation, during low-speed operation The rotational speed control effect of outputting high torque and low torque during high speed operation can be achieved, and it is possible to cope with a very wide range of rotational speed changes.

A brushless DC motor rotational speed control apparatus according to an embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, which is a schematic configuration diagram of a rotational speed control device for a brushless DC motor according to the present invention , the rotational speed control device for a brushless DC motor according to the present invention includes one brushless DC motor 20, at least one Hall sensor component. 11, an inverter circuit 12, a gate drive circuit 13, and a microcontroller 14.

As shown in FIGS. 1 to 5, the brushless DC motor 20 is provided with two stators 21 and one rotor 22.
The two stators 21 are arranged and installed along a homologous axis.
Each stator 21 includes a main body 211 having an annular shape.
On the main body 211, stator teeth 212 extending toward the center of the main body 211 are installed.
A tip 213 is installed at the end of each stator tooth 212.
A coil 214 having a predetermined number of gates is wound and installed on each stator tooth 213.

The gap between each stator 21 and the adjacent chip 213 is 2 mm to 5 mm. If the gap is smaller than 2 mm, winding is difficult. If the gap is larger than 5 mm, unnecessary magnetic force is easily generated and the cost is high.
In addition, the chips 213 of the two stators 21 intersect and surround each other and have a circular hole-like structure form.

The rotor 22 is installed relative to the circular hole structure of the two stators 21.
The rotor 22 is installed on the shaft 221 so as to surround the plurality of permanent magnets 222.
Moreover, all the permanent magnets 222 are arranged and installed on the outer periphery of the shaft 221 in such a manner that the N poles / S poles are arranged so as to intersect each other.

Each stator tooth 212 has an electrical angle of 180 ° / m between the adjacent coils 214. m is the number of stators.
Here, there is no doubt that the relationship between the mechanical angle and the electrical angle is determined by the number of stators.
Each stator tooth 212 has an electrical angle of 180 ° / m between each adjacent coil. m is the number of stators.
Therefore, one cycle of electrical angles does not correspond to one cycle of mechanical angles.
In the embodiment of the present invention, two stators 21 are taken as an example, each stator 21 has eight stator teeth 212, and one period of the electrical angle is 1/4 of the rotation angle of the rotor 22. It corresponds to.
At this time, even if the electrical angle is a sensing voltage in a certain angle, it changes to a sensing voltage detected at a different mechanical angle.
If the mechanical angles are different, a change occurs in the sensed voltage based on the mechanical structure of the number of stators 21.

At least one Hall sensor component 11 is installed in the vicinity of the rotor 22 of the brushless DC motor 20.
Thus, a corresponding current signal is generated in accordance with the change in the position of the permanent magnet 222 of the rotor 22.
In the present embodiment, three Hall sensor components 11 that are electrically connected to the microcontroller 14 are installed around the rotor 22 of the brushless DC motor 20.
One Hall sensor component senses the rotational speed of the rotor, one Hall sensor component senses the timing of current exchange, and one Hall sensor component senses and determines the rotational direction of the rotor. .

The inverter circuit 12 is electrically connected between the two stators 21 of the brushless DC motor 20 and the DC power supply.
The inverter circuit 12 is composed of at least four electronic components.
Each electronic component is electrically connected to constitute the inverter circuit 12.
In the embodiment of the present invention, there are eight electronic components.
The inverter circuit 12 employs a series or parallel connection method and is electrically connected.

The gate drive circuit 13 constitutes an electrical connection between the microcontroller 14 and the inverter circuit 12.
The microcontroller 14 is connected to the external rotation speed control signal and the current signal of at least one Hall sensor component 11.
The electronic component is a transistor.

As shown in the embodiment of FIGS. 1 and 2, the inverter circuit 12 includes eight transistors Q1 to Q8.
The transistors Q1 to Q4 are connected to a single stator coil circuit.
The transistors Q5 to Q8 are connected to another stator coil circuit.
The gate drive circuit 13 is connected to the transistors Q1 to Q8, respectively.
Thereby, the open or shut-off of the transistors Q1 to Q8 is controlled.

In addition, the gate drive circuit 13 is controlled based on the received rotation speed control signal and the signal fed back to the microcontroller 14 by the hall sensor component 11 to transmit the signal to the inverter circuit 12.
The inverter circuit 12 simultaneously activates a plurality of electronic components, switches the electromagnetic field of the corresponding electronic components, and forms an N pole / S pole intersection.
As a result, the coil circuits of the two stators 21 are simultaneously activated and alternately driven, and the gate drive circuit 13 controls the open or shut-off of the transistors Q1 to Q8.
As a result, the coil circuits of the two stators 21 are alternately energized.

Alternatively, the gate drive circuit 13 is controlled based on the received rotation speed control signal and the signal fed back to the microcontroller 14 by the hall sensor component 11 to transmit the signal to the inverter circuit 12.
The inverter circuit 12 drives only some electronic components and switches to electronic components that affect any stator.
In this way, the coil circuit of the arbitrary stator 21 is driven, and the energized stator 21 and the corresponding rotor 22 form an interaction electromagnetic field, and the gate drive circuit 13 controls the open or shut-off of the transistors Q1 to Q8. To do.
Thereby, the coil circuit of the arbitrary stator 21 is single-phase energized.

In principle, the rotational speed control device for a brushless DC motor according to the present invention constitutes an electrical connection between the two stators 21 and the DC power source through the inverter circuit 12 when in use.
Moreover, it corresponds to the integrated operation of the microcontroller 14 and the gate drive circuit 13, and based on the received rotational speed control signal and the signal transmitted by the hall sensor component 11, the coil circuit of the two stators 21 (see FIG. 5). Are alternately driven or a coil circuit (see FIG. 6) of an arbitrary stator 21 is driven to form an interacting electromagnetic field in the energized stator 21 and rotor 22.
Thus, the rotor 22 rotates continuously in the same direction.

In the above embodiment, the rotor position of the motor is sensed and detected using the hall sensor component, and the rotor position of the motor is sensed and detected using another sensor.

That is, the brushless DC motor device of the present invention does not require a high-output power source, and can operate the brushless DC motor to be applied by starting it from a stopped state.
Moreover, after the operation to the set rotational speed, the operation can be switched to the operation in which the coil circuit of an arbitrary stator is driven.
As a result, the restriction on the power source for using the brushless DC motor can be reduced, and a power saving effect can be provided in the full-time operation process of the brushless DC motor.

Furthermore, when implementing the brushless DC motor 20 to which the present invention is applied, a plurality of silicon steel pieces having the same structural form as the stators 21 are overlapped to constitute each.
In the present embodiment, eight stator teeth 212 are installed on each stator 21, and eight permanent magnets 222 are installed on the rotor 22.
Moreover, the length of each permanent magnet 222 in the axial direction preferably includes the installation range of the chips 213 of the two stators 21.

Naturally, each stator 21 can be provided with an even number of stator teeth, and each rotor 22 can be provided with an even number of permanent magnets 222.
For example, the eight stator teeth 212 correspond to the four permanent magnets 222, or each stator 21 is provided with an even number of stator teeth 212, and the rotor 22 is connected to the stator 21. A corresponding even number of permanent magnets 222 are installed.

The brushless DC motor to which the present invention is applied should be designed with different numbers of stator teeth and rotor permanent magnets for each stator depending on the actual size. Can do.
In addition, the coil rectification timing of each stator can be effectively controlled by the corresponding operation of the appropriate drive circuit, and the operation efficiency of the entire brushless DC motor can be easily improved, or the range of change in the rotational speed can be expanded. it can.

Compared with the prior art, the rotational speed control device of the brushless DC motor of the present invention outputs a high torque during low-speed operation through a method of alternately driving two stator coil circuits, and an arbitrary stator. Low torque can be output during high-speed operation through the method of driving the coil circuit.
The rotation speed control method can start the motor operation without using a high-output power source.

Moreover, after the motor operation reaches the set rotational speed, it can be switched to the operation with the method of driving the coil circuit of any stator, which not only reduces the limitation of the power supply for using the brushless DC motor, Power saving effect is provided in the full-time operation process of brushless DC motor.
Thus, the brushless motor control device can achieve a rotational speed control effect that outputs high torque during low-speed operation and low torque during high-speed operation, and can cope with a very wide range of rotational speed changes.

  By summing up the descriptions of the above embodiments, the operation, use, and effects of the present invention can be fully understood. However, the embodiment described above is merely a preferred embodiment of the present invention, and is not intended to limit the scope of the utility model registration claim of the present invention. That is, all simple changes and modifications having the same effect based on the scope of the claims of the utility model registration of the present invention and the contents of the description shall fall within the scope of the present invention.

Q1 to Q8 Transistor 11 Hall sensor component 12 Inverter circuit 13 Gate drive circuit 14 Microcontroller 20 Brushless DC motor 21 Stator 211 Main body 212 Stator teeth 213 Chip 214 Coil 22 Rotor 221 Shaft 222 Permanent magnet

Claims (15)

The brushless DC motor rotational speed control system includes at least a brushless DC motor, an inverter circuit, a gate drive circuit, and a microcontroller.
The brushless DC motor is provided with two stators and one rotor. The two stators are arranged along a homologous axis, and each stator has an annular shape. A stator tooth extending to the center of the main body is installed on the main body, a tip is installed at each stator tooth end, and a predetermined gate is provided on each stator tooth. A plurality of coils are wound, and the two stator chips cross and surround each other to form a circular hole structure, and the rotor has a two stator circular hole structure The rotor is installed so as to surround a plurality of permanent magnets on the shaft, and all the permanent magnets are arranged so that N poles / S poles intersect at the outer periphery of the shaft. Arranged in
The inverter circuit is electrically connected between two stators of a brushless DC motor and a DC power source,
The gate drive circuit constitutes an electrical connection between the microcontroller and the inverter circuit, and is connected to an external rotation speed control signal by the microcontroller. In the brushless DC motor rotational speed control system, at least one Hall sensor component is installed around the rotor of the brushless DC motor.
The rotation speed control system of a brushless DC motor according to claim 1, wherein a corresponding current signal is generated in accordance with a change in a permanent magnet position of the rotor. The rotation speed control system for a brushless DC motor according to claim 1, wherein the inverter circuit employs a series or parallel connection system and is electrically connected. The rotation speed control system for a brushless DC motor according to claim 1, wherein a range of a gap between the adjacent chips is 2 mm to 5 mm. Each stator tooth has an electrical angle (180 degrees / m) between adjacent coils. 2. The rotational speed control system for a brushless DC motor according to claim 1, wherein m is the number of stators. In the rotational speed control system of the brushless DC motor, at least one Hall sensor component is installed around the rotor of the brushless DC motor, and is electrically connected to the microcontroller.
3. The brushless DC motor rotational speed control system according to claim 2, wherein the rotational speed of the rotor is detected by the hall sensor component. In the rotational speed control system of the brushless DC motor, at least two hall sensor components are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller.
The brushless DC motor according to claim 2, wherein the rotation speed of the rotor is detected by one Hall sensor component, and the timing of current exchange is detected by another Hall sensor component. Rotational speed control system. In the rotational speed control system of the brushless DC motor, at least three Hall sensor parts are installed around the rotor of the brushless DC motor, and are electrically connected to the microcontroller.
One of the hall sensor components detects the rotational speed of the rotor, another one of the hall sensor components detects the current exchange timing, and another one of the hall sensor components detects the rotor. The rotational speed control system for a brushless DC motor according to claim 2, wherein the rotational direction is detected and determined.   The gate electrode is connected to the external rotation speed control signal and the current signal of the at least one hall sensor component by the microcontroller, and based on the received rotation speed control signal and the signal transmitted by the hall sensor component. 3. The rotational speed control system for a brushless DC motor according to claim 2, wherein the circuit is driven to alternately drive the coil circuits of the two stators.   The microcontroller 14 is connected to the external rotational speed control signal and the current signal of the at least one hall sensor component, and based on the received rotational speed control signal and the signal transmitted by the hall sensor component, an arbitrary The rotational speed control system for a brushless DC motor according to claim 2, wherein the stator coil circuit is driven, and the stator energized thereby forms a interacting electromagnetic field.   The brushless according to any one of claims 1 to 10, wherein each stator is provided with eight stator teeth, and each rotor is provided with eight permanent magnets. DC motor rotation speed control system. Each stator is provided with an even number of stator teeth,
The rotational speed control system for a brushless DC motor according to any one of claims 1 to 10, wherein an even number of permanent magnets are installed in the rotor. Each stator is provided with an even number of stator teeth,
The rotational speed control system for a brushless DC motor according to any one of claims 1 to 10, wherein an even number of permanent magnets corresponding to the stator are installed in the rotor.   The rotation speed control system for a brushless DC motor according to any one of claims 1 to 10, wherein each of the stators is configured by overlapping a plurality of silicon steel pieces having a homologous structure.   The rotational speed control of the brushless DC motor according to any one of claims 1 to 10, wherein an axial length of each permanent magnet includes an installation range of the two stator chips. system.