KR20040017723A - Single Phase Motor - Google Patents

Abstract

PURPOSE: A single phase switched reluctance motor is provided to allow the motor to be quickly driven, while achieving improved reliability of motor control operation. CONSTITUTION: A single phase switched reluctance motor comprises a stator, a rotor, a ring magnet(150), a parking magnet(160) opposed to the ring magnet, a sensor unit(300), and a driving control unit for applying driving pulses in accordance with the position and speed of the rotor detected by the sensor unit. The stator includes n salient poles formed at the inside of the stator, wherein each of the salient poles is wound with a field coil. The rotor includes n salient poles formed at the outside of the rotor, wherein the rotor rotates by the electromagnetic force generated between the stator and the rotor. The ring magnet(150) includes n/2 N-poles and n/2 S-poles disposed into a ring shape along the circumference of the rotor. The parking magnet parks the rotor in the forward direction torque generating area by the attractive force between the ring magnet and the parking magnet. The sensor unit senses the position and speed of the rotor.

Description

Single Phase Switched Reluctance Motor {Single Phase Motor}

The present invention relates to a single phase switched reluctance motor, in particular a single phase switch reluctance which eliminates the step of artificially aligning the position of the rotor such that the motor rotor is braked in an unstable equilibrium position so that the rotor does not rotate in reverse when waiting for driving. It's about a motor.

Hereinafter, the configuration and operation of the single-phase switched reluctance motor of the related art will be described in detail with reference to FIGS. 1 to 6.

FIG. 1 is a driving circuit diagram of a typical single phase switched reluctance motor, and FIG. 2 is a structural cross-sectional view of a rotor for braking a conventional single phase switched reluctance motor.

A single phase switched reluctance motor (SRM) includes a driver (not shown), a stator (20) wound around field coils (W1 to W3) receiving current from the driver, and the stator (20). It consists of a rotor (Rotor, 10) is rotated by the reluctance torque generated between the stator 20 when the current flows in the field coil in the inner side of.

The stator 20 includes a yoke formed in a cylindrical shape having an upper and lower sides open, a plurality of protrusions protruding at regular intervals from the inner wall of the yoke to the rotor 10 located at the center of the yoke, and wound on the protrusions. It consists of field coils W1 to W3.

The rotor 10 has a plurality of cores protruding from the circumference of the circumferentially spaced six protrusions are formed to form a rotor core 18, the center of the rotor 10 to transmit the driving force of the motor The rotary shaft 17 is driven to rotate together with the rotor 10. Bearings 19 are provided at the top and bottom of the rotor 10 for supporting and rotating the bottom of the rotor 10, and the core 18 of the rotor is located between the upper and lower bearings 19.

The driving unit receives a detection signal from a plurality of optical means or a sensor means 30, such as a Hall sensor for detecting the position or speed of the rotor 10 to turn on the switch connected to a pair of field coils facing each other sequentially The current is conducted as it generates a drive pulse that turns on / off.

Single-phase switched reluctance motor has two switches (SW1, SW2), the switch is turned on / off at the same time, the switch connects two opposite poles at the same time the field coil (W1 to wrap around the poles) W3) is connected so that the current applied from the driver flows to the field coil.

When a current flows in the field coil, a reluctance torque is generated between the stator 20 and the rotor 10 to be rotated and driven in a direction in which the magnetic resistance is minimized.

In addition, the switched reluctance motor uses a magnetic force to wait for the rotor 10 to be driven at a specific position so that the rotational drive in the direction (forward direction) to be controlled, the two magnets that cause the magnetic force is the rotor A ring magnet 15 formed in a ring shape on a circumferential surface of the ring 10 and a parking magnet 16 fixed to a position parallel to the ring magnet to form a mutual magnetic force with the ring magnet 15. When the electron 10 is braked, the rotor 10 is fixed to a specific position by mutual attraction forces acting on the two magnets, which are illustrated in FIGS. 2 and 3.

3 is a configuration diagram of a ring magnet and a parking magnet of a conventional single-phase switched reluctance motor, as shown in the number of N poles and S poles is equal to the number of protrusion poles (6), respectively. In addition, the parking magnet has a single N-pole and S-pole having the same width as that of the ring magnet and are located opposite the ring magnet.

The rotation period per rotor pole of the rotor is equal to 360 degrees / 6, and the rotation period according to the magnetic change of the N pole is also equal to 360 degrees / 6. Therefore, the period of the inductance (magnetic induction) waveform formed between each salient pole of the rotor and stator is 60 degrees. 4 illustrates a pulse waveform and an inductance profile generated by the sensor means of the conventional single phase switched reluctance motor.

The sensor means includes a first sensor and a second sensor, and detects a change in the magnetic force line of the ring magnet to generate a pulse signal. Pulse signals generated from the first sensor and the second sensor, respectively, are referred to as a first pulse signal and a second pulse signal, and each signal has a time difference according to a sensing position, and the period of the signal is 60 degrees.

The driving unit induces rotation of the motor by applying a driving pulse to the stator in a logical common section of the rising signal of the first sensor, the rising signal of the second sensor, and the falling signal of the first sensor output from the sensor means. The common section is bold-lined on the inductance profile of FIG. 4, which means that the inclination of the inductance waveform is a positive section, which is a forward torque generating region for inducing the rotor to rotate in the forward direction. In this forward torque generation region, the driving unit may control the rotation speed of the motor by adjusting the width of the driving pulse.

5 is a diagram illustrating an unstable equilibrium position (UEP) of a rotor of a conventional single phase switched reluctance motor, and FIG. 6 is a diagram illustrating an alignment step of the rotor of a conventional single phase switched reluctance motor.

The positional relationship between the ring magnet and the parking magnet may be classified into a stable equilibrium position (SEP) or an unstable equilibrium position (UEP) during standby of the single phase switched reluctance motor. Assuming that the rotating direction (forward direction) is a counterclockwise direction, when the fixed rotor is driven again between 0 to +30 degrees, the salient pole of the rotor 10 close to the salient pole A of the stator 20 to which current is applied (A ') is rotated in a direction to be matched, i.e. counterclockwise, wherein the ring magnet and the parking magnet have different poles facing each other to work with each other, and this position is called a stable equilibrium position.

However, as shown in FIG. 5, when the driving pulse is applied while the rotor 10 is fixed at -30 to 0 degrees, the driving pulse is rotated in the clockwise direction, thereby causing an abnormal control of the device in which the motor is embedded. As the magnet 15 and the parking magnet 16 are opposite to each other, only repulsive force is generated between the same poles, so that the left and right alignment of the rotor 10 is not possible due to mutual attraction. This is called location (UEP). When the ring magnet and the parking magnet form a relationship between the UEP, the rotor 10 rotates in the reverse direction, which may cause a failure of a device such as deterioration of durability of the motor.

Therefore, when the rotor is braked in the UEP, as shown in FIG. 6, the motor driving unit applies an alignment pulse for a predetermined time before the driving pulse is applied to completely match the rotor pole A 'of the rotor and the pole pole A of the stator. After that, there was an inconvenience in that a correction step was performed to block the alignment pulse so that the salient pole A 'of the rotor 10 was fixed between 0 to +30 degrees. As a result, the speed of the motor control is lowered, which causes the inconvenience of using a device in which the motor is embedded.

The present invention has been made to solve the above-mentioned problems of the prior art, the rotation of the motor at all times without the correction step for aligning the position of the rotor when the motor waits to drive in a position to generate the reverse rotation torque, the rotation at all times A single phase switched reluctance motor is provided in which the number of N poles and S poles of a ring magnet and a parking magnet is reduced to the number of pole poles / 2, respectively, so as to brake and wait for driving in a position that generates a self-rotating forward torque.

1 is a driving circuit diagram of a typical single phase switched reluctance motor;

2 is a structural cross-sectional view of a rotor for braking a conventional single phase switched reluctance motor;

3 is a configuration diagram of a ring magnet and a parking magnet of a conventional single-phase switched reluctance motor,

4 is a view showing a pulse waveform generated by the sensor means of the conventional single-phase switched reluctance motor,

5 shows the unstable equilibrium position (UEP) of a rotor of a conventional single phase switched reluctance motor,

6 is a diagram illustrating an alignment step of a rotor of a conventional single-phase switched reluctance motor,

7 is a structural cross-sectional view of the rotor for braking the single-phase switched reluctance motor of the present invention;

8 is a configuration diagram of a ring magnet and a parking magnet of the single-phase switched reluctance motor of the present invention;

9 shows the stable equilibrium position SEP of the rotor of the single-phase switched reluctance motor of the present invention;

10 shows the unstable equilibrium position (UEP) of the rotor of the single phase switched reluctance motor of the present invention;

FIG. 11 is a diagram showing pulse waveforms generated by the sensor means of the single-phase switched reluctance motor of the present invention.

<Explanation of symbols on main parts of the drawings>

10: rotor A ': rotor pole

20: stator A: pole of stator

15, 150: ring magnet 16, 160: parking magnet

17: axis of rotation 18: rotor core

19: bearing 30, 300: sensor

W1, W2, W3: Field coil SW1, SW2: Switch

In the single-phase switched reluctance motor according to the present invention for solving the above problems, n protrusions are formed inward, a field coil is wound around the protrusions, and n protrusions are formed outward, and between the stators. The rotor rotated by the generated electromagnetic force, a ring magnet in which n / 2 N-poles and n / 2 S-poles are arranged in a ring shape on the circumferential surface of the rotor, and the ring magnets face each other. And a parking magnet arranged to face the other side of the ring magnet and a parking magnet configured to brake the rotor to a forward torque generating region by an attractive force acting between the ring magnets, and to detect position and speed information of the rotor. Means and a drive control unit for applying a drive pulse according to the position and speed information of the rotor sensed by the sensor means. The.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The driving method of the single-phase switched reluctance motor of the present invention is the same as that of FIG. 1, and FIG. 7 is a structural cross-sectional view of the rotor for braking the single-phase switched reluctance motor of the present invention, and FIG. 8 is a single-phase switched reluctance of the present invention. It is a block diagram of the ring magnet and parking magnet of a motor.

As shown in FIG. 7, the rotor has a rotor core 180 formed by stacking cores having six protrusions protruded outward from the circumference at a predetermined interval, and a rotating shaft 170 transmitting a driving force of the motor at the center thereof. It is rotationally driven together with the rotor. Bearings 190 are located at the top and bottom of the rotor to support and rotate the bottom of the rotor, and the core 180 of the rotor is located between the upper and lower bearings 190.

The ring magnet 150 is molded by a mold material between one of the inner and outer surfaces of the rotor by a mold material to be fixed to the rotating shaft, or fixed to the end of the rotating shaft and integrally rotated with the rotor. Accordingly, when the driving pulse for allowing the rotor to be rotated is blocked, the ring magnet 150 is braked by an electromagnetic force acting between the parking magnet 160, so that the parking magnet is horizontally opposed to the ring magnet. .

As shown in FIGS. 7 and 8, the ring magnet 150 has N poles and S poles arranged alternately from left to right, and the N poles and S poles each have a number of protrusion poles / 2. Therefore, the rotation period of the N pole is 120 degrees, and the rotation period of the S pole is also 120 degrees, which is twice the rotation angle of the salient pole. In addition, the parking magnet is composed of a single N pole and S pole having the same spacing as the N pole and the S pole of the ring magnet.

The sensor means 300 is a first that outputs three signals required by the driving unit (not shown) for driving control of the motor as the N pole and the S pole of the ring magnet are reduced to (number of pole poles / 2), respectively. To third sensors S1 to S3.

Fig. 9 shows the stable equilibrium position (SEP) of the rotor of the single-phase switched reluctance motor of the present invention, and Fig. 10 shows the unstable equilibrium position (UEP) of the rotor of the single-phase switched reluctance motor of the present invention.

In the case of the single-phase switched reluctance motor composed of the rotor 10 having six salient poles and the stator 20 having six salient poles, the rotation period of the salient pole is 60 degrees because the angle between the salient poles is 60 degrees. When the center of the salient pole A of the stator is 0 degrees, the position of the salient pole A 'of the rotor has a displacement of 30 degrees to the right and 30 degrees to the left. For convenience, the right side is represented by + and the left side is represented by-from the center.

The stable equilibrium position (SEP) is a position where different poles face each other so that attractive force acts between the ring magnet and the parking magnet, and the rotor pole A of the rotor is located between 0 to 30 degrees so that the motor driving unit generates a driving pulse. When applied, the rotor rotates counterclockwise. The 0 to 30 degrees is an area in which the forward rotation torque is generated.

The unstable equilibrium position (UEP) as shown in FIG. 10 is a position where the same poles are opposed to each other so that the repulsive force acts between the ring magnet 150 and the parking magnet 160. Compared with FIG. 9, the ring magnet and the parking This is a positional relationship formed when the rotor is rotated by 60 degrees as the pole spacing of the magnet is doubled. Since the rotation period of the salient pole A 'is 60 degrees, the salient pole A' is waiting to be driven in the same region between 0 and 30 degrees, that is, the region in which the forward rotation torque is generated, as shown in FIG.

That is, as the period of the N pole-> N pole of the ring magnet 150 is 120 degrees, and the period of the N-> S pole is 60 degrees, the ring so that the rotation period of the salient pole A 'is equal to 60 degrees By varying the number of poles of the magnet 150, the positional relationship between the ring magnet and the parking magnet is such that the rotor pole is positioned in an area that always generates a forward rotational torque regardless of the stable equilibrium position or the unstable equilibrium position. .

11 is a diagram showing the pulse waveform generated by the sensor means 300 of the single-phase switched reluctance motor of the present invention, wherein the N and S poles of the ring magnet 150 are respectively (number of pole poles / 2). As shown in FIG. 2, the driving unit includes first to third sensors S1 to S3 for outputting three signals required for driving control of the motor. In addition to the first and second sensors of the prior art, a third sensor is auxiliaryly attached to output three signals.

The plurality of sensors are arranged horizontally on the other side of the ring magnet to detect the periodic change in the polarity of the north pole and the south pole of the ring magnet that is integrally rotated with the rotor, to generate the first to third pulse signal .

Accordingly, the first to third pulse signals have an angle of 360 degrees divided by (number of poles / 2), that is, a period of 120 degrees, and are generated by delaying each pulse signal by an angle difference according to the arrangement of each sensor. .

In addition, when looking at the inductance profile of the rotor, the rotation period of the salient pole is 60 degrees, the region having positive slope is the region where the forward rotation torque is generated (0 to 30 degrees), and the region having the negative slope is the reverse direction. It is an area (-30 to 0 degrees) at which rotation torque is generated.

The motor driving unit drives the rotor to rotate in a logical common section AND of the rising signal of the first pulse signal, the rising signal of the second pulse signal, and the falling signal of the third pulse signal sensed by the sensor means. Apply a pulse. Therefore, the inductance profile (bold line processing) corresponding to the common section always has a positive slope, wherein the rotor rotates in the forward direction at all times regardless of the positional relationship between the ring magnet and the parking magnet by an applied driving pulse. Will be.

As described above, the present invention has been described using an example of a single-phase switched reluctance motor in which the number of salient poles of the stator and the rotor is six, but the position of the salient pole and the magnet may be changed according to the system to which the motor is applied.

The single-phase switched reluctance motor of the present invention configured as described above comprises a ring magnet composed of 1/2 N pole and S pole of the number of poles of the rotor and the stator, and a single N having the same width as the pole of the ring magnet. Although the rotor is braked in the unbalanced stable position (UEP) by the parking magnet composed of poles and S poles, the rotor is rotated in the forward direction to ensure the reliability and safety of the control, and also to align the driving standby position of the rotor. As a separate correction step is omitted, the motor can be driven more quickly.

Claims (9)

A stator having n protrusions formed inward and a field coil wound around the protrusions; A rotor formed with n protrusions on the outside and rotated by electromagnetic force generated between the stators; a ring magnet in which n / 2 N poles and n / 2 S poles are arranged in a ring shape on the circumferential surface of the rotor; A parking magnet disposed opposite the ring magnet and braking the rotor to a forward torque generating region by an attractive force acting between the ring magnets; Sensor means disposed opposite the other side of the ring magnet to detect position and speed information of the rotor; Single phase switched reluctance motor, characterized in that it comprises a drive control unit for applying a drive pulse in accordance with the position and speed information of the rotor sensed by the sensor means. The method of claim 1, Single ring switched reluctance motor, characterized in that the ring magnet is fixed to any one of the inner and outer surfaces of the rotor. The method of claim 1, The ring magnet is a single-phase switched reluctance motor, characterized in that the N pole and the S pole are arranged alternately left and right. The method of claim 1, The ring magnet is a single phase switched reluctance motor, characterized in that fixed to the end of the rotary shaft to be integrally rotated with the rotor. The method of claim 1, The parking magnet is a single-phase switched reluctance motor, characterized in that consisting of a single N pole and S pole having the same distance as the N pole and S pole of the ring magnet. The method of claim 1, The sensor means comprises a first to third sensor, the single phase switched reluctance motor, characterized in that arranged on the other side of the ring magnet. The method of claim 6, The sensor means generates first to third pulse signals, respectively, as the polarity of the magnet of the ring magnet periodically changes, and the first to third pulse signals each have a period of an angle divided by 360 degrees n / 2. Single phase switched reluctance motor characterized by having. The method of claim 6, Single phase switched reluctance motor, characterized in that the pulse signal is delayed by the angle difference according to the arrangement of the first to third sensors. The method according to claim 1 or 6, The motor driving unit rotates the rotor in a logical common section (AND) of the rising signal of the first pulse signal, the rising signal of the second pulse signal, and the falling signal of the third pulse signal sensed by the sensor means. Single-phase switched reluctance motor, characterized in that for applying a driving pulse.