Single-phase variable-speed asynchronous motor, control method thereof and air conditioner

Abstract

The application provides a single-phase variable-speed asynchronous motor, a control method thereof and an air conditioner. The single-phase variable-speed asynchronous motor comprises a stator core, N stator slots are formed on the stator core, N is an even number not less than 12 and divisible by 4, winding wires are embedded in the N stator slots one by one, the axial ends of the stator core are respectively provided with control plates, the two ends of the N winding wires are respectively electrically connected with the control plates, the control plates are configured to selectively connect or disconnect two of the N winding wires according to different target paths when the single-phase variable-speed asynchronous motor is at different rotating speeds, and the N winding wires are electrically connected to the target paths at different rotating speeds. According to the application, the operating requirements at different rotating speeds are ensured, all the winding wires are electrically connected to the corresponding target paths at different rotating speeds, the additional winding consumption is not increased, the winding wires are not idle, and the motor manufacturing cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of motor manufacturing technology, specifically relating to a single-phase variable speed asynchronous motor and its control method, and an air conditioner. Background Technology

[0002] The number of poles in an AC asynchronous motor determines its synchronous speed. Motor design requires consideration not only of speed but also efficiency and temperature rise; therefore, the designed operating speed should be as close as possible to the synchronous speed. Air conditioning unit motors often have a wide range of speed requirements depending on the location and application, and a single AC asynchronous motor cannot simultaneously meet both efficiency and speed demands.

[0003] The prior art discloses a pole-changing and speed-changing stator winding control method, but this stator winding relies on four single-pole double-throw switches to control the pole-changing of the stator winding, resulting in idle motor windings and high winding cost. Summary of the Invention

[0004] Therefore, the present invention provides a single-phase variable speed asynchronous motor and its control method, as well as an air conditioner, which can overcome the shortcomings of the prior art in which the stator winding of the asynchronous motor is controlled by pole changing, resulting in idle motor windings and high winding cost.

[0005] To address the aforementioned problems, this invention provides a single-phase variable-speed asynchronous motor, comprising a stator core having N stator slots, where N is an even number not less than 12 and divisible by 4.

[0006] Each of the N stator slots is fitted with a corresponding winding wire. Each of the two ends of the stator core has a control board. The two ends of the N winding wires are electrically connected to the control board. The control board is configured to selectively connect or disconnect two strands of the N winding wires according to different target paths when the single-phase variable speed asynchronous motor is at different speeds. At different speeds, all N winding wires are electrically connected to the target path, and the windings in the target path corresponding to each speed are full-pitch windings.

[0007] In some implementations...

[0008] N=32. The winding lines in the stator slots are sequentially spaced 1, 2, 3, ..., 30, 31, 32 along the circumference of the stator core. The target path includes an eight-pole main phase path and an eight-pole secondary phase path. The winding sequence of the eight-pole main phase path is: [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]. -[2-31], current flows in from 31 and out from 27, and a switching circuit is provided between the two connected winding wires respectively; the winding sequence of the eight-pole secondary phase path is: [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29], current flows in from 1 and out from 29, and a switching circuit is provided between the two connected winding wires respectively.

[0009] In some implementations...

[0010] The target path also includes a four-pole main phase path and a four-pole secondary phase path. The winding sequence of the four-pole main phase path is: [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29], with current flowing in from 6 and out from 29. A switching circuit is provided between the two connected windings. The winding sequence of the four-pole secondary phase path is: [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25], with current flowing in from 2 and out from 25. A switching circuit is provided between the two connected windings.

[0011] In some implementations...

[0012] The target path also includes a two-pole main phase path and a two-pole secondary phase path. The winding sequence of the two-pole main phase path is: [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25], with current flowing in from 12 and out from 25. A switching circuit is provided between the two connected windings. The winding sequence of the two-pole secondary phase path is: [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17], with current flowing in from 4 and out from 17. A switching circuit is provided between the two connected windings.

[0013] In some implementations...

[0014] The switching circuit includes a transistor.

[0015] In some implementations...

[0016] The control board is clamped between the end of the stator core and the corresponding motor end cover.

[0017] In some implementations...

[0018] The number of turns of the winding wire embedded in each of the stator slots is the same.

[0019] The present invention also provides a control method for a single-phase variable speed asynchronous motor, wherein the single-phase variable speed asynchronous motor is the aforementioned single-phase variable speed asynchronous motor, and the control method includes:

[0020] Obtain motor speed control commands;

[0021] The motor speed is obtained according to the acquired motor speed control command;

[0022] The target path is selected and controlled to match the motor speed based on the motor speed.

[0023] In some implementations...

[0024] When the motor speed is the first speed, N=32, and the target path includes an eight-pole main phase path and an eight-pole secondary phase path, control [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]-[2-31] to form the eight-pole main phase path current flow, and control [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29] to form the eight-pole secondary phase path current flow; or,

[0025] When the motor speed is the second speed, N=32, and the target path includes a four-pole main phase path and a four-pole secondary phase path, control [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29] to form the four-pole main phase path current flow, and control [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25] to form the four-pole secondary phase path current flow; or...

[0026] When the motor speed is the third speed, N=32, and the target path includes a two-phase main path and a two-phase secondary path, control [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25] to form the current flow of the two-phase main path, and control [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17] to form the current flow of the two-phase secondary path.

[0027] Among them, the first speed < the second speed < the third speed.

[0028] The present invention also provides an air conditioner.

[0029] This includes the aforementioned single-phase variable speed asynchronous motor.

[0030] This invention provides a single-phase variable speed asynchronous motor and its control method, as well as an air conditioner. The control board is used as a component to switch the connection or disconnection of different winding lines. It can be implemented through corresponding software programs, thereby realizing the change of the number of poles of the motor and ensuring the operation requirements of different speeds. It can expand the design range of the motor speed, thereby facilitating the motor efficiency to be in a higher range. At the same time, at different speeds, all the winding lines are electrically connected to the corresponding target path, without increasing the amount of additional winding, and the winding lines are not idle, thus reducing the manufacturing cost of the motor. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the connection between the stator core, winding wires and control board in a single-phase variable speed asynchronous motor according to an embodiment of the present invention. The state of the control board is not its actual assembled state.

[0032] Figure 2 for Figure 1 The wiring diagram for various target paths on one of the control boards shows that the thick solid lines indicate the eight-pole main phase and sub-phase paths, the thin solid lines indicate the two-pole main phase and sub-phase paths, and the dashed lines indicate the four-pole main phase and sub-phase paths. The other control board is exactly the same.

[0033] Figure 3 for Figure 1 A schematic diagram of the winding of the eight-pole main phase (M main-m) / secondary phase (A secondary-a) path after the stator core is unfolded;

[0034] Figure 4 for Figure 1 A schematic diagram of the winding of the four-pole main phase (M main-m) / secondary phase (A secondary-a) path after the stator core is unfolded;

[0035] Figure 5 for Figure 1 A schematic diagram of the winding of the primary phase (M-m) / secondary phase (A-a) path after the stator core is unfolded.

[0036] The reference numerals in the attached figures are as follows:

[0037] 100. Stator core; 101. Stator slot; 102. Winding wire; 200. Control board. Detailed Implementation

[0038] See also Figures 1 to 5 As shown, according to an embodiment of the present invention, a single-phase variable speed asynchronous motor is provided, including a stator core 100, wherein the stator core 100 is provided with N stator slots 101, where N is an even number not less than 12 and divisible by 4 (e.g., 12, 16, 24, 32, etc.). Each of the N stator slots 101 is fitted with a winding wire 102 (formed by multiple windings). Each of the two ends of the stator core 100 has a control board 200. The two ends of the N winding wires 102 are electrically connected to the control board 200. The control board 200 is configured to selectively connect or disconnect two strands of the N winding wires 102 according to different target paths when the single-phase variable speed asynchronous motor is at different speeds. At different speeds, all N winding wires 102 are electrically connected to the target path. The windings in the target path corresponding to each speed are full-pitch windings, which are also full-pitch coils, i.e., y = Z, where y is the coil pitch, y is an integer, Z is the number of stator slots in the stator core, and p is the number of motor pole pairs. In this technical solution, the control board 200 is used as a component to switch the connection or disconnection of different winding wires 102. It can be implemented by corresponding software programs, thereby realizing the change of the number of poles of the motor and ensuring the operation requirements of different speeds. This expands the design range of the motor speed, which helps to keep the motor efficiency in a higher range. At the same time, at different speeds, all the winding wires 102 are electrically connected to the corresponding target path, without increasing the amount of additional winding. The winding wires are not idle, which reduces the manufacturing cost of the motor.

[0039] like Figure 2 , Figure 3 As shown, in some embodiments, N=32, and the winding lines 102 in the stator slots 101 are sequentially spaced 1, 2, 3, ..., 30, 31, 32 along the circumference of the stator core 100 (e.g., ...). Figures 2 to 5 The markings in the text (which can also be understood as the corresponding stator slot numbers) indicate that the target path includes an octagonal main phase path and an octagonal sub-phase path, wherein, as shown in the text... Figure 3 As shown, the winding sequence of the eight-pole main phase path is: [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]-[2-31]. Current flows in from 3 and out from 27. Switching circuits are respectively provided between the two connected winding wires 102. It should be noted that at this time, 3-6, 10-7, 11-14, 18-15, 19-22, 26-23, and 30-27 form adjacent eight poles with opposite polarities. Figure 3As shown, the winding sequence of the eight-pole secondary phase path is: [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29]. Current flows in from 1 and out from 29. Switching circuits are respectively provided between the two connected winding wires 102. It should be noted that at this time, 1-4, 8-5, 9-12, 16-13, 17-20, 24-21, 25-28, and 32-29 form adjacent eight poles with opposite polarities. Thus, when the stator core is eight-pole, all the winding wires 102 are electrically connected to the corresponding target path, without increasing the amount of additional winding, and the winding wires are not idle, reducing the manufacturing cost of the motor. It should be noted that the winding lines 102 within the same pair of brackets represent the same pole, while any two adjacent pairs of brackets have opposite polarities due to the different winding directions. The following four-pole and two-pole windings all follow this rule.

[0040] like Figure 2 , Figure 4 As shown, the target path also includes a four-pole main phase path and a four-pole secondary phase path. The winding sequence of the four-pole main phase path is: [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29], with current flowing in from 6 and out from 29. Switching circuits are respectively provided between the two connected winding wires 102. The winding sequence of the four-pole secondary phase path is: [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25], with current flowing in from 2 and out from 25. Switching circuits are respectively provided between the two connected winding wires 102. It should be noted that the windings under the same pole adopt a concentric winding method from the inside to the outside. Thus, when the stator core is four-pole, all the winding wires 102 are electrically connected to the corresponding target path, without increasing the amount of additional winding, and the winding wires are not idle, thereby reducing the manufacturing cost of the motor.

[0041] like Figure 2 , Figure 5As shown, the target path also includes a two-pole main phase path and a two-pole secondary phase path. The winding sequence of the two-pole main phase path is: [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25], with current flowing in from 12 and out from 25. Switching circuits are respectively provided between the two connected winding wires 102. The winding sequence of the secondary phase path is: [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17], with current flowing in from 4 and out from 17. Switching circuits are respectively provided between the two connected winding wires 102. It should be noted that the windings under the same pole are concentric and wound from the inside out. Thus, when the stator core is two-pole, all the winding wires 102 are electrically connected to the corresponding target path, without increasing the amount of additional winding, and the winding wires are not idle, thereby reducing the manufacturing cost of the motor.

[0042] It should be noted that, although Figures 3 to 5 The diagram shows a single winding, but it is actually a diagram showing 32 winding wires 102 forming a corresponding path according to the target path, rather than a single winding.

[0043] The switching circuit can be a conventional control switching circuit, such as a transistor, specifically a MOS switch, which can be programmed to control its switching using configured software. For example, when the base voltage of the transistor is greater than 0.7V, the collector and emitter are conducting, and when the base voltage is less than 0.7V, the collector and emitter are not conducting, thereby realizing the switching function of the switching circuit.

[0044] The control board 200 can be assembled separately at the shaft end of the stator core 100. In some embodiments, the control board 200 is clamped between the end of the stator core 100 and the corresponding motor end cover. The motor end cover is used to seal the shaft end of the motor and position the control board 200 at the same time, simplifying the assembly process.

[0045] The number of turns of the winding wire 102 embedded in each of the stator slots 101 is the same, so as to form a symmetrical stator magnetic field.

[0046] According to an embodiment of the present invention, a control method for a single-phase variable-speed asynchronous motor is also provided, wherein the single-phase variable-speed asynchronous motor is the single-phase variable-speed asynchronous motor described above, and the control method includes:

[0047] Obtain motor speed control commands;

[0048] The motor speed is obtained according to the acquired motor speed control command;

[0049] The target path is selected and controlled to match the motor speed based on the motor speed.

[0050] In some implementations, when the motor speed is a first speed, N=32, and the target path includes an eight-pole main phase path and an eight-pole secondary phase path, the current flow in the eight-pole main phase path is controlled to form [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]-[2-31], and the current flow in the eight-pole secondary phase path is controlled to form [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29]. It is understood that the switching circuits in the eight-pole main phase path and the eight-pole secondary phase path are controlled to be connected, while other switching circuits are controlled to be disconnected; or...

[0051] When the motor speed is the second speed, N=32, and the target path includes a four-pole main phase path and a four-pole secondary phase path, the current flow in the four-pole main phase path is controlled to be formed by [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29], and the current flow in the four-pole secondary phase path is controlled to be formed by [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25]. It can be understood that the switching circuits in the four-pole main phase path and the four-pole secondary phase path are controlled to be connected, while other switching circuits are controlled to be disconnected; or...

[0052] When the motor speed is the third speed, N=32, and the target path includes a two-phase main path and a two-phase secondary path, the current flow in the two-phase main path is controlled to be formed by [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25], and the current flow in the two-phase secondary path is controlled to be formed by [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17]. It can be understood that the switching circuits in the two-phase main path and the two-phase secondary path are controlled to be connected, while other switching circuits are controlled to be disconnected.

[0053] Among them, the first speed < the second speed < the third speed.

[0054] For example, under a 220V / 50Hz power supply, if you want to use a speed below 750rpm, select the eight-pole option, and control it according to the target path corresponding to the first speed. If you want to use a speed in the range of 750-1500rpm, select the four-pole option, and control it according to the target path corresponding to the second speed. If you want to use a speed above 1500rpm, select the two-pole option, and control it according to the target path corresponding to the third speed.

[0055] According to embodiments of the present invention, an air conditioner is also provided, including the aforementioned single-phase variable-speed asynchronous motor. It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0056] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A single-phase variable speed asynchronous motor, comprising a stator core (100), wherein the stator core (100) has N stator slots (101) formed thereon, where N is an even number not less than 12 and divisible by 4, characterized in that, N stator slots (101) are each fitted with a corresponding winding wire (102). Each end of the stator core (100) has a control board (200). The two ends of the N winding wires (102) are electrically connected to the control board (200). The control board (200) is configured such that when the single-phase variable speed asynchronous motor is at different speeds, two strands of the N winding wires (102) can be selectively connected or disconnected according to different target paths. At different rotational speeds, all N strands of the winding wires (102) are electrically connected to the target path, and the windings in the target path corresponding to each rotational speed are all full-pitch windings; N=32, and the winding wires (102) in the stator slots (101) are sequentially spaced 1, 2, 3, ..., 30, 31, 32 along the circumference of the stator core (100). The target path includes an eight-pole main phase path and an eight-pole secondary phase path, wherein the winding sequence of the eight-pole main phase path is: [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]-[2-31], current flows in from 3 and out from 31, and a switching circuit is provided between the two connected winding wires (102); the winding sequence of the eight-pole secondary phase path is: [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29], current flows in from 1 and out from 29, and a switching circuit is provided between the two connected winding wires (102).

2. The single-phase variable speed asynchronous motor according to claim 1, characterized in that, The target path also includes a four-pole main phase path and a four-pole secondary phase path. The winding sequence of the four-pole main phase path is: [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29]. Current flows in from 6 and out from 29. Switching circuits are respectively provided between the two connected winding lines (102). The winding sequence of the four-pole secondary phase path is: [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25]. Current flows in from 2 and out from 25. Switching circuits are respectively provided between the two connected winding lines (102).

3. The single-phase variable speed asynchronous motor according to claim 2, characterized in that, The target path also includes a main phase path and a secondary phase path. The winding sequence of the main phase path is: [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25]. Current flows in from 12 and out from 25. Switching circuits are provided between the two connected windings (102). The winding sequence of the secondary phase path is: [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17]. Current flows in from 4 and out from 17. Switching circuits are provided between the two connected windings (102).

4. The single-phase variable speed asynchronous motor according to claim 2 or 3, characterized in that, The switching circuit includes a transistor.

5. The single-phase variable speed asynchronous motor according to claim 1, characterized in that, The control board (200) is clamped between the end of the stator core (100) and the corresponding motor end cover.

6. The single-phase variable speed asynchronous motor according to claim 1, characterized in that, The number of turns of the winding wire (102) embedded in each of the stator slots (101) is the same.

7. A control method for a single-phase variable speed asynchronous motor, characterized in that, The single-phase variable speed asynchronous motor is any one of claims 1 to 6, and the control method includes: Obtain motor speed control commands; The motor speed is obtained according to the acquired motor speed control command; The target path is selected and controlled to match the motor speed based on the motor speed.

8. The control method according to claim 7, characterized in that, When the motor speed is the first speed, N=32, and the target path includes an eight-pole main phase path and an eight-pole secondary phase path, control [3-6]- [10-7]- [11-14]- [18-15]- [19-22]- [26-23]- [27-30]-[2-31] to form the current flow of the eight-pole main phase path, and control [1-4]-[8-5]-[9-12]-[16-13]-[17-20]-[24-21]-[25-28]-[32-29] to form the current flow of the eight-pole secondary phase path; or, When the motor speed is the second speed, N=32, and the target path includes a four-pole main phase path and a four-pole secondary phase path, control [6-11-5-12]-[19-14-20-13]-[22-27-21-28]-[3-30-4-29] to form the current flow of the four-pole main phase path, and control [2-7-1-8]-[15-10-16-9]-[18-23-17-24]-[31-26-32-25] to form the current flow of the four-pole secondary phase path; or, When the motor speed is the third speed, N=32, and the target path includes a two-phase main path and a two-phase secondary path, control [12-21-11-22-10-23-9-24]-[5-28-6-27-7-26-8-25] to form the current flow of the two-phase main path, and control [4-13-3-14-2-15-1-16]-[29-20-30-19-31-18-32-17] to form the current flow of the two-phase secondary path. Among them, the first speed < the second speed < the third speed.

9. An air conditioner, characterized in that, The single-phase variable speed asynchronous motor includes any one of claims 1 to 6.

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