Motor unit and motor controller thereof

Abstract

The invention provides a motor unit and a motor controller thereof. The motor unit is provided with the motor controller and a motor. The motor controller comprises a switching circuit, a control circuit and a phase signal generating circuit. The phase signal generating circuit receives a phase input signal to generate a phase output signal to the control circuit. The control circuit firstly enables the phase output signal to maintain a first digital level in a first duration to drive the motor, so that a rotor is separated from a dead zone. And then the control circuit enables the phase output signal to maintain a second digital level in a second duration to drive the motor, so that the rotor is separated from the dead zone. The motor unit and the motor controller can make commutation smooth.

Description

Technical Field

[0001] The present invention relates to a motor unit, and in particular to a single-phase motor unit. Background Art

[0002] Traditionally, motor drive methods can be categorized into two types. One uses Hall sensors to switch phases and drive the motor. The other drives the motor without Hall sensors. When single-phase motor systems are equipped with Hall sensors and asymmetric silicon steel laminations, this asymmetry can cause commutation jitter and lead to noise issues. Therefore, a new technology is needed to overcome this problem. Summary of the Invention

[0003] In view of the aforementioned problems, an object of the present invention is to provide a motor unit and a motor controller thereof that can achieve smooth commutation.

[0004] The present invention provides a motor unit comprising a motor controller, a motor, a comparator, and a Hall effect sensor, wherein the motor controller is used to drive the motor. A fan comprises the motor, a fan blade, and the Hall effect sensor. The motor comprises a rotor, a silicon steel sheet, and a coil, wherein the motor is a single-phase motor. The rotor is divided into two north magnetic poles and two south magnetic poles for switching the motor phase. In a static state, the intersection of the north magnetic pole and the south magnetic pole corresponds to a mechanism zero point position. The Hall effect sensor is positioned corresponding to the mechanism zero point position.

[0005] The motor controller comprises a switching circuit, a control circuit, and a phase signal generating circuit. The Hall sensor detects the position of the rotor and generates a first voltage signal and a second voltage signal. The comparator generates a phase input signal based on the first and second voltage signals. The switching circuit supplies a motor current to the motor. The control circuit generates a plurality of control signals to control the switching circuit. The phase signal generating circuit receives the phase input signal and generates a phase output signal to the control circuit. The control circuit switches the motor phase based on the phase output signal. The control circuit first maintains the phase output signal at a first digital level for a first duration to drive the motor, thereby allowing the rotor to escape a dead zone. Then, the control circuit maintains the phase output signal at a second digital level for a second duration to drive the motor, thereby allowing the rotor to escape the dead zone. The first duration may be adjacent to the second duration. The first digital level may be different from the second digital level. The motor may further have a first terminal and a second terminal. The first terminal has a first signal, and the second terminal has a second signal. A waveform of the first signal may be synchronous with and opposite to a waveform of the phase output signal. A waveform of the second signal may be synchronous with and identical to a waveform of the phase output signal.

[0006] According to an embodiment of the present invention, the control circuit stores an initial level of the phase input signal. The first digital level may be opposite to the initial level.

[0007] According to another embodiment of the present invention, the control circuit stores an initial level of the phase input signal, and the first digital level may be the same as the initial level.

[0008] The control circuit can cause the phase output signal to be asynchronous with the phase input signal during the first duration and the second duration. After a certain time point, the control circuit can cause a waveform of the phase output signal to be synchronous with and identical to a waveform of the phase input signal. Before the certain time point, the control circuit can cause a waveform of the phase output signal to be asynchronous with a waveform of the phase input signal. The motor unit and the motor controller can be configured to operate in a startup mode by causing the rotor to exit the dead zone at least twice or more. Furthermore, the motor unit and the motor controller can be configured to perform a forward / reverse rotation function by causing the rotor to exit the dead zone at least twice or more. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a schematic diagram of a fan according to an embodiment of the present invention.

[0010] Figure 2 FIG. 1 is a schematic diagram of a motor unit according to an embodiment of the present invention.

[0011] Figure 3 1 is a timing diagram of a first embodiment and a second embodiment of the present invention.

[0012] Figure 4 1 is a timing diagram of a third embodiment and a fourth embodiment of the present invention.

[0013] Explanation of the accompanying drawings: 1-fan; 10-motor unit; 11-motor controller; 100-rotor; 110-silicon steel sheet; 120-coil; 130-fan blade; 140-Hall sensor; N-north magnetic pole; S-south magnetic pole; 150-switching circuit; 151-first transistor; 152-second transistor; 153-third transistor; 154-fourth transistor; M-motor; 160-control circuit; 170-phase signal generating circuit; 180-comparator; O1-first terminal; O2-second terminal; C1-first control signal; C2-second control signal; C3-third control signal; C4-fourth control signal; V1-first voltage signal; V2-second voltage signal; Vpi-phase input signal; Vpo-phase output signal; VCC-voltage source; GND-third terminal; T-time point; T1-first duration; T2-second duration; Vo1-first signal; Vo2-second signal. DETAILED DESCRIPTION

[0014] The following description will make the purpose, features, and advantages of the present invention more apparent.Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0015] Figure 1 Figure 1 is a schematic diagram of a fan 1 according to an embodiment of the present invention. The fan 1 has a motor M, a fan blade 130, and a Hall sensor 140, where the dotted line indicates the zero position of the mechanism. The motor M has a rotor 100, a silicon steel sheet 110, and a coil 120, where the motor M can be a single-phase motor. The rotor 100 can be divided into two north magnetic poles N and two south magnetic poles S to switch the motor phase. According to an embodiment of the present invention, the rotor 100 can be divided into 2M north magnetic poles N and 2M south magnetic poles S to switch the motor phase, where M is a positive integer and M is greater than or equal to 1. The coil 120 is wound around the silicon steel sheet 110 and changes the magnetic field through electromagnetic induction to drive the rotor 100. The silicon steel sheet 110 can have a symmetrical structure. In a static state, this symmetrical structure allows the intersection of the north magnetic pole N and the south magnetic pole S to correspond to the zero position of the mechanism. In addition, the Hall sensor 140 can be set at a position corresponding to the zero position of the mechanism.

[0016] Figure 2 Figure 1 is a schematic diagram of a motor unit 10 according to an embodiment of the present invention. The motor unit 10 includes a motor controller 11, a motor M, a comparator 180, and a Hall sensor 140. The motor controller 11 is configured to drive the motor M. The motor M further includes a first terminal O1 and a second terminal O2. The first terminal O1 receives a first signal Vo1, and the second terminal O2 receives a second signal Vo2. The motor controller 11 includes a switching circuit 150, a control circuit 160, and a phase signal generating circuit 170. The switching circuit 150 includes a first transistor 151, a second transistor 152, a third transistor 153, and a fourth transistor 154 for supplying a motor current to the motor M. The first transistor 151 is coupled to a voltage source VCC and the first terminal O1, while the second transistor 152 is coupled to the first terminal O1 and a third terminal GND. The third transistor 153 is coupled to the voltage source VCC and the second terminal O2, while the fourth transistor 154 is coupled to the second terminal O2 and the third terminal GND. The first transistor 151, the second transistor 152, the third transistor 153, and the fourth transistor 154 can be a P-type metal oxide semiconductor transistor or an N-type metal oxide semiconductor transistor. Figure 2 As shown, the first transistor 151 and the third transistor 153 are two P-type metal oxide semiconductor transistors, and the second transistor 152 and the fourth transistor 154 are two N-type metal oxide semiconductor transistors.

[0017] The control circuit 160 generates a first control signal C1, a second control signal C2, a third control signal C3, and a fourth control signal C4 to control the conduction of the first transistor 151, the second transistor 152, the third transistor 153, and the fourth transistor 154, respectively. The Hall sensor 140 detects the position of the rotor 100 and generates a first voltage signal V1 and a second voltage signal V2. The comparator 180 generates a phase input signal Vpi to the phase signal generation circuit 170 based on the first voltage signal V1 and the second voltage signal V2. The phase signal generation circuit 170 receives the phase input signal Vpi and generates a phase output signal Vpo to the control circuit 160. The control circuit 160 switches the motor phase based on the phase output signal Vpo. In other words, the motor controller 11 drives the motor M based on the phase output signal Vpo.

[0018] Figure 3 1 is a timing diagram of a first embodiment and a second embodiment of the present invention. According to the first embodiment of the present invention, the control circuit 160 can first store an initial level of the phase input signal Vpi. Figure 3 As shown, the initial level is a high level. The control circuit 160 can then cause the phase output signal Vpo to maintain a level opposite to the initial level for a first duration T1 to drive the motor M, allowing the rotor 100 to escape a dead zone. That is, the control circuit 160 can drive the motor M in a direction opposite to the stored phase. The control circuit 160 can then cause the phase output signal Vpo to maintain the same level as the initial level for a second duration T2 to drive the motor M, allowing the rotor 100 to escape the dead zone. That is, the control circuit 160 can drive the motor M in a direction identical to the stored phase. The first duration T1 can be adjacent to the second duration T2. Furthermore, the control circuit 160 can cause the phase output signal Vpo to be asynchronous with the phase input signal Vpi during the first duration T1 and the second duration T2. It should be noted that during these two driving operations, the control circuit 160 does not reference the high / low level turning points of the phase input signal Vpi to drive the motor M. Therefore, these two driving operations can be considered an alignment process, the primary purpose of which is to ensure that the rotor 100 has a sufficiently large swing angle to smoothly exit the dead zone. Then, after a time point T, the control circuit 160 synchronizes and makes the waveform of the phase output signal Vpo identical to the waveform of the phase input signal Vpi, thereby ensuring smooth operation of the motor M. Furthermore, the waveform of the first signal Vo1 can be synchronized with and opposite to the waveform of the phase output signal Vpo. The waveform of the second signal Vo2 can be synchronized with and identical to the waveform of the phase output signal Vpo.

[0019] According to a second embodiment of the present invention, the control circuit 160 may not store the initial level. Therefore, storing the initial level of the phase input signal Vpi is not a necessary technical feature of the present invention. The control circuit 160 may first maintain the phase output signal Vpo at a low level for a first duration T1 to drive the motor M, allowing the rotor 100 to escape a dead zone. The control circuit 160 may then maintain the phase output signal Vpo at a high level for a second duration T2 to drive the motor M, allowing the rotor 100 to escape the dead zone. The first duration T1 may be adjacent to the second duration T2. Furthermore, the control circuit 160 may desynchronize the phase output signal Vpo with the phase input signal Vpi during the first duration T1 and the second duration T2. It should be noted that during these two driving actions, the control circuit 160 does not reference a high / low level turning point of the phase input signal Vpi to drive the motor M. Therefore, these two driving actions can be considered a positioning process, the primary purpose of which is to ensure that the rotor 100 has a sufficiently large swing angle to successfully escape the dead zone. After time T, the control circuit 160 can synchronize the waveform of the phase output signal Vpo with and be identical to the waveform of the phase input signal Vpi, thereby enabling smooth operation of the motor M. Furthermore, the waveform of the first signal Vo1 can be synchronized with and opposite to the waveform of the phase output signal Vpo. The waveform of the second signal Vo2 can be synchronized with and identical to the waveform of the phase output signal Vpo.

[0020] Figure 4 1 is a timing diagram of a third embodiment and a fourth embodiment of the present invention. According to the third embodiment of the present invention, the control circuit 160 can first store an initial level of the phase input signal Vpi. Figure 4As shown, the initial level is a high level. The control circuit 160 can then maintain the phase output signal Vpo at the same level as the initial level during a first duration T1 to drive the motor M, allowing the rotor 100 to escape a dead zone. Specifically, the control circuit 160 can drive the motor M in the same direction as a stored phase. The control circuit 160 can then maintain the phase output signal Vpo at a level opposite to the initial level during a second duration T2 to drive the motor M, allowing the rotor 100 to escape the dead zone. Specifically, the control circuit 160 can drive the motor M in the opposite direction of the stored phase. The first duration T1 can be adjacent to the second duration T2. Furthermore, the control circuit 160 can cause the phase output signal Vpo to be asynchronous with the phase input signal Vpi during the first duration T1 and the second duration T2. It should be noted that during these two driving operations, the control circuit 160 does not reference the high / low level turning points of the phase input signal Vpi to drive the motor M. Therefore, these two driving operations can be considered a positioning process, the primary purpose of which is to ensure that the rotor 100 has a sufficiently large swing angle to smoothly exit the dead zone. Subsequently, after time T, the control circuit 160 can synchronize the waveform of the phase output signal Vpo with and be identical to the waveform of the phase input signal Vpi, thereby ensuring smooth operation of the motor M. Furthermore, the waveform of the first signal Vo1 can be synchronized with and opposite to the waveform of the phase output signal Vpo. The waveform of the second signal Vo2 can be synchronized with and identical to the waveform of the phase output signal Vpo.

[0021] According to a fourth embodiment of the present invention, the control circuit 160 may not store the initial level. Therefore, storing the initial level of the phase input signal Vpi is not a necessary technical feature of the present invention. The control circuit 160 may first maintain the phase output signal Vpo at a high level for a first duration T1 to drive the motor M, allowing the rotor 100 to escape a dead zone. The control circuit 160 may then maintain the phase output signal Vpo at a low level for a second duration T2 to drive the motor M, allowing the rotor 100 to escape the dead zone. The first duration T1 may be adjacent to the second duration T2. Furthermore, the control circuit 160 may desynchronize the phase output signal Vpo with the phase input signal Vpi during the first duration T1 and the second duration T2. It should be noted that during these two driving actions, the control circuit 160 does not reference a high / low level turning point of the phase input signal Vpi to drive the motor M. Therefore, these two driving actions can be considered a positioning process, the primary purpose of which is to ensure that the rotor 100 has a sufficiently large swing angle to smoothly escape the dead zone. After time T, the control circuit 160 can synchronize the waveform of the phase output signal Vpo with and be identical to the waveform of the phase input signal Vpi, thereby enabling smooth operation of the motor M. Furthermore, the waveform of the first signal Vo1 can be synchronized with and opposite to the waveform of the phase output signal Vpo. The waveform of the second signal Vo2 can be synchronized with and identical to the waveform of the phase output signal Vpo.

[0022] The first duration T1 and the second duration T2 can be a first predetermined value and a second predetermined value, respectively. Through continuous experimentation and testing of various motor load and fan combinations, the first duration T1 can be within a range of 0.0001 to 10 seconds, and the second duration T2 can be within a range of 0.0001 to 10 seconds. The preferred embodiment is that the first duration T1 can be within a range of 0.001 to 1 second, and the second duration T2 can be within a range of 0.001 to 1 second. Furthermore, the first duration T1 and the second duration T2 can be adjustable, respectively, to a first value and a second value. The motor controller 11 can further include a voltage divider circuit and a register, wherein the voltage divider circuit can be composed of two or more resistors. The user can adjust the first duration T1 or the second duration T2 based on the voltage divider circuit. The user can also adjust the first duration T1 or the second duration T2 based on the register. The first duration T1 and the second duration T2 can be related to the motor load. The heavier the motor load, the longer the first duration T1 and the second duration T2. When the motor load is lighter, the first duration T1 and the second duration T2 are shorter.

[0023] Specifically, by allowing the rotor 100 to escape the dead zone at least twice or more, the above four embodiments can all enable the motor unit 10 and the motor controller 11 to operate in a start-up mode, wherein the start-up mode can be a forced start-up mode. Similarly, by allowing the rotor 100 to escape the dead zone at least twice or more, the above four embodiments can all enable the motor unit 10 and the motor controller 11 to perform a forward and reverse rotation function. In other words, the motor unit 10 and the motor controller 11 in the present invention can allow the rotor 100 to escape the dead zone twice or more to overcome the problem of dead zone locking. In summary, the above four embodiments can all have the following characteristics: the control circuit 160 can first allow the phase output signal Vpo to maintain a first digital level within a first duration T1 to drive the motor M, so that the rotor 100 can escape a dead zone. The control circuit 160 can then maintain the phase output signal Vpo at a second digital level for a second duration T2 to drive the motor M, allowing the rotor 100 to escape the dead zone. The first duration T1 can be adjacent to the second duration T2, and the first digital level can be different from the second digital level. The control circuit 160 can desynchronize the phase output signal Vpo with the phase input signal Vpi during the first duration T1 and the second duration T2. After time T, the control circuit 160 can synchronize the waveform of the phase output signal Vpo with and be identical to the waveform of the phase input signal Vpi, thereby ensuring smooth operation of the motor M. That is, before time T, the control circuit 160 can desynchronize the waveform of the phase output signal Vpo with the waveform of the phase input signal Vpi.

[0024] According to the four aforementioned embodiments, when the motor unit 10 includes symmetrical silicon steel laminations 110, the motor unit 10 and motor controller 11 enable smooth commutation and reduced noise during steady-state operation of the motor M, thereby overcoming the problems of the prior art. In other words, the motor controller 11 can be applied to a symmetrical silicon steel lamination mechanism. Furthermore, when the motor unit 10 includes symmetrical silicon steel laminations 110, fan manufacturers can utilize the silicon steel laminations 110 in a stator mechanism of a three-phase motor, thereby saving costs.

[0025] While the present invention has been described with reference to preferred embodiments, it should be understood that the invention is not limited to the embodiments provided. Rather, the present invention is intended to cover various modifications and similar arrangements that would be apparent to one skilled in the art. Therefore, the claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.

[0026] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the claims of the present invention should fall within the scope of the present invention.

Claims

1. A motor unit, characterized in that: Include: A motor, wherein the motor comprises a rotor and a symmetrical silicon steel sheet; and A motor controller, wherein the motor controller includes a switching circuit, a control circuit and a phase signal generating circuit, the motor controller is used to drive the motor, the switching circuit supplies a motor current to the motor, the control circuit generates a plurality of control signals to control the switching circuit, the phase signal generating circuit receives a phase input signal to generate a phase output signal to the control circuit, the control circuit switches the motor phase according to the phase output signal, the control circuit first maintains the phase output signal at a first digital level for a first duration to drive the motor so that the rotor leaves a dead zone, and then the control circuit maintains the phase output signal at a second digital level for a second duration to drive the motor so that the rotor leaves the dead zone, the first digital level being different from the second digital level.

2. The motor unit according to claim 1, wherein The control circuit stores an initial level of the phase input signal, and the first digital level is opposite to the initial level.

3. The motor unit according to claim 1, wherein The control circuit stores an initial level of the phase input signal, and the first digital level is the same as the initial level.

4. The motor unit according to claim 1, wherein The motor unit further includes a Hall sensor. The Hall sensor detects a position of the rotor and generates a first voltage signal and a second voltage signal.

5. The motor unit according to claim 4, wherein: The motor unit further includes a comparator, which is used to generate the phase input signal according to the first voltage signal and the second voltage signal.

6. The motor unit according to claim 1, wherein The rotor is divided into 2M north magnetic poles and 2M south magnetic poles to switch the motor phase, where M is a positive integer and M is greater than or equal to 1.

7. The motor unit according to claim 6, wherein: In a static state, an intersection of the north magnetic pole and the south magnetic pole corresponds to a mechanism zero point position.

8. The motor unit according to claim 1, wherein The motor unit further includes a Hall sensor, which is arranged at a position corresponding to a mechanism zero point.

9. The motor unit according to claim 1, wherein The motor unit is configured to operate in a starting mode by causing the rotor to escape from the dead zone at least twice or more.

10. The motor unit according to claim 1, wherein The motor unit is used to perform a forward and reverse rotation function by causing the rotor to escape from the dead zone at least twice or more.

11. The motor unit according to claim 1, wherein The control circuit causes the phase output signal to be asynchronous with the phase input signal during the first duration and the second duration.

12. The motor unit according to claim 1, wherein After a time point, the control circuit makes a waveform of the phase output signal synchronized with and identical to a waveform of the phase input signal.

13. The motor unit according to claim 12, wherein: Before the time point, the control circuit causes a waveform of the phase output signal to be asynchronous with a waveform of the phase input signal.

14. The motor unit according to claim 1, wherein The motor further has a first terminal and a second terminal. The first terminal has a first signal, and the second terminal has a second signal. A waveform of the first signal is synchronous with and opposite to a waveform of the phase output signal.

15. The motor unit according to claim 14, wherein A waveform of the second signal is synchronized with and identical to a waveform of the phase output signal.

16. The motor unit according to claim 1, wherein The first duration is a first predetermined value, and the second duration is a second predetermined value.

17. The motor unit according to claim 1, wherein The first duration is within a range of 0.0001 to 10 seconds, and the second duration is within a range of 0.0001 to 10 seconds.

18. The motor unit according to claim 1, wherein The first duration is a first adjustable value, and the second duration is a second adjustable value.

19. The motor unit according to claim 1, wherein The motor controller further includes a voltage divider circuit, and a user adjusts the first duration or the second duration according to the voltage divider circuit.

20. The motor unit according to claim 1, wherein The motor controller further has a register, and a user adjusts the first duration or the second duration according to the register.

21. The motor unit according to claim 1, wherein The first duration and the second duration are related to a motor load.

22. The motor unit according to claim 1, wherein When a motor load is heavier, the first duration and the second duration are longer; when the motor load is lighter, the first duration and the second duration are shorter.

23. The motor unit according to claim 1, wherein The motor unit enables the motor to switch phases smoothly in a steady-state operation state.

24. The motor unit according to claim 1, wherein The motor unit enables the motor to reduce noise in a steady-state operation.

25. The motor unit according to claim 1, wherein The symmetrical silicon steel sheet is applied to a stator mechanism of a three-phase motor.

26. The motor unit according to claim 1, wherein The motor is a single-phase motor.

27. A motor controller for driving a motor, characterized in that: The motor controller includes: a switching circuit for supplying a motor current to the motor; a control circuit for generating a plurality of control signals to control the switch circuit; and A phase signal generating circuit is used to receive a phase input signal to generate a phase output signal to the control circuit, wherein the control circuit switches the motor phase according to the phase output signal. The control circuit first causes the phase output signal to maintain a first digital level for a first duration to drive the motor so that a rotor escapes a dead zone. Then, the control circuit causes the phase output signal to maintain a second digital level for a second duration to drive the motor so that the rotor escapes the dead zone. The first digital level is different from the second digital level. After a time point, the control circuit causes a waveform of the phase output signal to be synchronized and identical to a waveform of the phase input signal.

28. The motor controller according to claim 27, wherein: Before the time point, the control circuit causes a waveform of the phase output signal to be asynchronous with a waveform of the phase input signal.

29. The motor controller according to claim 27, wherein: The control circuit stores an initial level of the phase input signal, and the first digital level is opposite to the initial level.

30. The motor controller according to claim 27, wherein: The control circuit stores an initial level of the phase input signal, and the first digital level is the same as the initial level.

31. The motor controller according to claim 27, wherein: The motor controller is configured to operate in a starting mode by causing the rotor to escape from the dead zone at least twice or more.

32. The motor controller according to claim 27, wherein: The motor controller is used to execute a forward and reverse rotation function by making the rotor escape from the dead zone at least twice or more.

33. The motor controller according to claim 27, wherein: The control circuit causes the phase output signal to be asynchronous with the phase input signal during the first duration and the second duration.

34. The motor controller according to claim 27, wherein: The motor further has a first terminal and a second terminal. The first terminal has a first signal, and the second terminal has a second signal. A waveform of the first signal is synchronous with and opposite to a waveform of the phase output signal.

35. The motor controller according to claim 34, wherein: A waveform of the second signal is synchronized with and identical to a waveform of the phase output signal.

36. The motor controller according to claim 27, wherein: The first duration is a first predetermined value, and the second duration is a second predetermined value.

37. The motor controller according to claim 27, wherein: The first duration is within a range of 0.0001 to 10 seconds, and the second duration is within a range of 0.0001 to 10 seconds.

38. The motor controller according to claim 27, wherein: The first duration is a first adjustable value, and the second duration is a second adjustable value.

39. The motor controller according to claim 27, wherein: The motor controller further includes a voltage divider circuit, and a user adjusts the first duration or the second duration according to the voltage divider circuit.

40. The motor controller according to claim 27, wherein: The motor controller further has a register, and a user adjusts the first duration or the second duration according to the register.

41. The motor controller according to claim 27, wherein: The first duration and the second duration are related to a motor load.

42. The motor controller according to claim 27, wherein: When a motor load is heavier, the first duration and the second duration are longer; when the motor load is lighter, the first duration and the second duration are shorter.

43. The motor controller according to claim 27, wherein: The motor controller enables the motor to switch phases smoothly in a steady-state operation state.

44. The motor controller according to claim 27, wherein: The motor controller enables the motor to reduce noise in a steady-state operation.

45. The motor controller of claim 27, wherein: The motor is a single-phase motor.

46. The motor controller of claim 27, wherein: The motor controller is applied to a symmetrical silicon steel sheet mechanism.

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