Winding coil connection method and device of motor, speed regulation method and device, motor and medium

Abstract

The invention discloses a winding coil connection method and device of a motor, a speed regulation method and device, the motor and a medium. The winding coil connection method comprises the steps that the winding coil connection method is applied to a single-phase permanent magnet motor, and critical rotating speeds matched with rotating speed requirements are set according to the different rotating speed requirements when the motor runs; wherein the minimum value of the critical rotating speed is larger than or equal to the grid-connected synchronous rotating speed of the motor, and the maximum value of the critical rotating speed is smaller than or equal to the maximum value of the rotating speed of the motor; and determining a series-parallel connection mode of the winding coil according to the critical rotation speed and the target rotation speed of the motor. According to the method, the no-load counter electromotive force of the motor during high-speed operation can be reduced only by changing the series-parallel connection mode of the winding coils, so that the defect that the cost is too high when the high-speed operation of the motor is met through a booster circuit is overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of motor grid connection, and in particular to a motor winding coil connection method, a speed regulation method, a device, a motor and a medium. Background Art

[0002] When the motor of the compressor in daily household appliances is connected to the grid, it can not only reduce the loss of the controller switching device, but also further improve the working efficiency of the compressor. However, when the motor of the compressor is connected to the grid and directly powered, its voltage is in an uncontrollable state. In order to make the compressor have better performance under grid-connected conditions, the no-load back EMF of the motor is generally set close to the grid voltage. However, the no-load back EMF of the motor is proportional to the frequency, and the speed is also proportional to the frequency. Therefore, when the motor speed is higher than its grid-connected synchronous speed, its no-load back EMF will also increase with the increase of speed. However, the cost of using a boost circuit to meet the high-speed operation of the motor is too high, so the method of reducing the no-load back EMF when the motor is running at high speed still needs to be improved. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defect in the prior art that the cost of using a boost circuit to meet the high-speed operation of a motor is too high, and to provide a motor winding coil connection method, a speed regulation method, a motor and a medium.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] In a first aspect, a method for connecting a winding coil of a motor is provided, which is applied to a single-phase permanent magnet motor. The method for connecting a winding coil comprises:

[0006] According to different speed requirements when the motor is running, a critical speed matching the speed requirement is set; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum value of the motor speed;

[0007] The series-parallel connection mode of the winding coils is determined according to the critical speed and the target speed of the motor.

[0008] Optionally, the setting of a critical speed matching the speed requirement includes:

[0009] After all winding coils are connected in series, the effective value of the no-load back EMF of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ; Among them, E m Indicates the effective value of the no-load back EMF of the motor.

[0010] Optionally, the motor has A poles and A teeth, and each tooth is wound with k coils, wherein A and k are both positive integers;

[0011] The setting of the critical speed matching the speed requirement further includes:

[0012] When k = 1, the winding current is i The coils are first connected in series to form a branch circuit, forming a total of m i series branches, and then connect the m i After the branches are connected in parallel, the corresponding motor's no-load back EMF reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i ; Among them, m i represents the factors of A other than 1, and i represents a positive integer greater than 1;

[0013] and / or,

[0014] When k≠1, q coils are selected from the A*k coils, and the q coils are connected in series and parallel according to a preset manner, so that the number of coils connected in series per phase is x. i The first line of; wherein, q is a multiple of A and q≤A*k, x i is a positive integer;

[0015] After the first circuit is operated, the corresponding motor's no-load back EMF effective value reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i .

[0016] Optionally, the setting of a critical speed matching the speed requirement further includes:

[0017] When k≠1, one coil is selected from each tooth of the motor for series connection to form a series branch containing A coils, and then A*k coils can form k series branches;

[0018] After all the k series branches are connected in series, the effective value of the no-load back EMF of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ;

[0019] Select p series branches from the k series branches, connect the p series branches according to a preset series-parallel connection method, and form a number of coils in series per phase. i * The second line of A, p is a positive integer and p<k, a i is a positive integer and a i+1 <ai <p;

[0020] After the second circuit is operated, the corresponding motor's no-load back EMF effective value reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i ; Among them, n switch_i =k*n switch_1 / a i .

[0021] Optionally, the first critical speed and the i-th critical speed are respectively [n min , n max ] is divided into several adjacent critical speed intervals; where n min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed;

[0022] The series-parallel connection mode of the winding coils is adjusted according to the critical speed range in which the target speed of the motor is located.

[0023] In a second aspect, a speed regulation method for a motor is provided, the speed regulation method comprising:

[0024] When the target speed is greater than the minimum value of the motor speed and less than or equal to the maximum value of the critical speed, the series-parallel connection mode of the winding coils is set by any of the above-mentioned winding coil connection methods of the motor to adjust the speed of the motor;

[0025] When the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed, a magnetic field weakening speed regulation mode is adopted.

[0026] In a third aspect, a winding coil connection device of a motor is provided, the winding coil connection device comprising:

[0027] A setting module, used to set a critical speed matching the speed requirement according to different speed requirements when the motor is running; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum speed of the motor;

[0028] Determination module: used to determine the series-parallel connection mode of the winding coil according to the critical speed and the target speed of the motor.

[0029] In a fourth aspect, a speed regulating device for a motor is provided, the device comprising the winding coil connecting device for the motor described above;

[0030] A regulating module, used for setting the series-parallel connection mode of the winding coils by any of the above-mentioned winding coil connection methods of the motor to regulate the speed of the motor when the target speed is greater than the minimum speed of the motor and less than or equal to the maximum speed of the critical speed;

[0031] A module is used to adopt a magnetic field weakening speed regulation mode when the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed.

[0032] In a fifth aspect, a motor is provided, comprising a winding composed of a plurality of coils, the motor comprising the above-mentioned winding coil connection device and / or the above-mentioned motor speed regulating device;

[0033] The motor has A poles and A teeth, and each tooth is wound with k coils, wherein A and k are both positive integers.

[0034] In a sixth aspect, a computer-readable medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the method for connecting the winding coils of the motor described above and / or the method for speed regulation of the motor described above are implemented.

[0035] The positive and progressive effect of the present invention is that according to different speed requirements when the motor is running, a critical speed matching the speed requirement is set, and then the series-parallel connection mode of the winding coils is determined according to the critical speed and the target speed of the motor. This method can reduce the no-load back electromotive force when the motor is running at high speed by simply changing the series-parallel connection mode of the winding coils, thereby solving the defect that the cost of using a boost circuit to meet the high-speed operation of the motor is too high. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flow chart of a method for connecting winding coils of a motor provided in Embodiment 1 of the present invention;

[0037] Figure 2 A speed interval diagram of a motor divided by a critical speed provided in Embodiment 1 of the present invention;

[0038] Figure 3 A winding coil circuit diagram of a 4-pole 4-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0039] Figure 4 A structural diagram of a winding coil circuit of a 4-pole 4-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0040] Figure 5 A winding coil circuit diagram of a 4-pole 4-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with 3 coils;

[0041] Figure 6A structural diagram of a winding coil circuit of a 4-pole 4-tooth motor provided by Embodiment 1 of the present invention, wherein each tooth is wound with 3 coils;

[0042] Figure 7 A winding coil circuit diagram of a 6-pole 6-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0043] Figure 8 A structural diagram of a winding coil circuit of a 6-pole 6-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0044] Fig. 9 A winding coil circuit diagram of a 6-pole 6-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with 3 coils;

[0045] Fig.10 A structural diagram of a winding coil circuit of a 6-pole 6-tooth motor provided by Embodiment 1 of the present invention, wherein each tooth is wound with 3 coils;

[0046] Fig.11 A winding coil circuit diagram of an 8-pole 8-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0047] Fig.12 A structural diagram of a winding coil circuit of an 8-pole 8-tooth motor provided in Example 1 of the present invention, wherein each tooth is wound with a coil;

[0048] Fig.13 A winding coil circuit diagram of an 8-pole 8-tooth motor provided by Embodiment 1 of the present invention, in which 6 coils are wound around each tooth;

[0049] Fig.14 A flow chart of a motor speed regulation method provided in Embodiment 2 of the present invention;

[0050] Fig.15 A schematic diagram of a module of a winding coil connection device for a motor provided in Embodiment 3 of the present invention;

[0051] Fig.16 A schematic diagram of a module of a motor speed regulating device provided in Embodiment 4 of the present invention;

[0052] Fig.17 This is a schematic diagram of the structure of a motor provided in Example 5 of the present invention. DETAILED DESCRIPTION

[0053] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0054] Example 1

[0055] In order to solve the defect that the cost is too high when a boost circuit is used to meet the high-speed operation of a motor, an embodiment of the present invention provides a method for connecting a winding coil of a motor, which is applied to a single-phase permanent magnet motor. Figure 1 This is a flow chart of a method for connecting the winding coils of a motor provided in Embodiment 1 of the present invention. The method for connecting the winding coils of a motor comprises the following steps:

[0056] Step 101, according to different speed requirements when the motor is running, set a critical speed that matches the speed requirement; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum value of the motor speed.

[0057] According to the set critical speed, the motor speed can be divided into speed ranges more reasonably. Figure 2 , the horizontal value represents the motor speed. According to the different motor speeds, its speed is divided into several speed intervals, among which, Figure 2 The rpm in the figure is the motor speed per minute, n min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed, n s Indicates the grid-connected synchronous speed of the motor, n switch_1 、n switch_2 and n switch_i Indicates the critical speed corresponding to different speed requirements when the motor is running. The minimum value of the motor speed is set because when the motor speed is lower than the minimum value of the motor speed, the motor is limited by the mechanical structure of the compressor, which will cause resonance; the maximum value of the motor speed is set because when the motor speed is higher than the maximum value of the motor speed, the electromagnetic noise of the motor is too large. Preferably, the minimum value of the critical speed can be made equal to the grid-connected synchronous speed of the motor, so that the number of winding coils can be reduced as much as possible while meeting the target speed of the motor.

[0058] Step 102: Determine the series-parallel connection mode of the winding coils according to the critical speed and the target speed of the motor.

[0059] By comparing the target speed of the motor with the critical speed, the speed range in which the target speed of the motor falls can be obtained, and then the series-parallel connection mode of the winding coils can be accurately adjusted to match the target speed of the motor. Among them, the method of adjusting the series-parallel connection of the winding coils includes but is not limited to using a wire tap to connect a switching switch, so as to switch between multiple series-parallel connection modes of the winding coils to meet different speed requirements of the motor.

[0060] In this embodiment, when the motor is connected to the grid, the grid directly supplies power to it. Therefore, the voltage is in an uncontrollable state. In order to make the motor have better performance under grid-connected conditions, its no-load back EMF is generally designed to be closer to the grid voltage. However, the operating speed range of the motor is about 700rpm-4500rpm.

[0061] E=4.44K w NfΦ (1)

[0062] f=pn / 60 (2)

[0063] Where, E represents the no-load back EMF of the motor, K w represents the winding coefficient (its value is less than or equal to 1, and for a single-phase permanent magnet motor with A poles and A teeth, its value is equal to 1), N represents the number of series turns per phase of the motor, f represents the frequency of the motor, Ф represents the magnetic flux per pole of the motor, p represents the number of poles of the motor, and n represents the required speed of the motor. Among them, when the value of f is equal to the grid frequency, the corresponding motor speed is the grid-connected synchronous speed. When the motor is off-grid (non-grid-connected state, controlled by the controller), according to formula (1) and formula (2), the no-load back EMF of the motor is proportional to the number of series turns per phase of the motor N and the frequency f of the motor, and the required speed of the motor is proportional to the frequency f of the motor. Therefore, when the required speed of the motor is higher than the grid-connected speed, the no-load back EMF of the motor will also increase with the increase of the required speed of the motor, so that the maximum voltage allowed by the controller also needs to increase accordingly. When the motor speed increases to a certain extent, the no-load back EMF can be reduced by reducing the number of series turns per phase of the motor winding.

[0064] Therefore, in order to achieve the highest efficiency when the motor is directly connected to the power grid, it is necessary to select a reasonable number of motor poles and teeth so that the motor is in a light-load and low-speed condition under the power grid frequency. Because the speeds of 4-pole 4-tooth, 6-pole 6-tooth and 8-pole 8-tooth motors under the power grid frequency are 1500rpm, 1000rpm and 750rpm respectively, they are more in line with the target conditions, so 4-pole 4-tooth, 6-pole 6-tooth and 8-pole 8-tooth are the best motor pole and tooth combinations.

[0065] In one embodiment, setting a critical speed that matches the speed requirement includes: after all the coils of the windings are operated in series, the effective value of the no-load back electromotive force of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ; Among them, E m Indicates the effective value of the no-load back EMF of the motor.

[0066] When the allowable voltage of the motor is constant, when all the coils of the winding are connected in series, the number of series coils per phase connected to the motor winding can be maximized. At this time, when the corresponding no-load back EMF effective value reaches Em, the target speed of the motor is minimum.

[0067] In one embodiment, the motor has A poles and A teeth, and each tooth is wound with k coils, wherein A and k are both positive integers; setting the critical speed matching the speed requirement also includes: when k=1, each A / m of the winding is i The coils are first connected in series to form a branch, forming a total of m i series branches, and then connect m i After the branches are connected in parallel, the corresponding motor's no-load back EMF reaches E m The speed at which the critical speed is ith is called the i-th critical speed, and the i-th critical speed is recorded as n switch_i ; Among them, m i represents a factor of A other than 1, i represents a positive integer greater than 1; preferably, the number of turns of each coil on the tooth is the same.

[0068] In this embodiment, when k=1, n is set in this way. switch_1 , which can make the critical speed range of the motor more reasonably divided and better meet the different speed requirements of the motor.

[0069] In one embodiment, the motor has k coils wound around each tooth, A and k are both positive integers; setting a critical speed matching the speed requirement, further comprising: when k≠1, selecting q coils from A*k coils, connecting the q coils in a preset series-parallel manner, forming a series connection of x coils per phase. i The first line of; wherein, q is a multiple of A and q≤A*k, x i is a positive integer; after the first circuit is operated, the corresponding motor's no-load back EMF effective value reaches E m The speed at which the critical speed is ith is called the i-th critical speed, and the i-th critical speed is recorded as n switch_i Preferably, the number of turns of each coil on the tooth is the same.

[0070] When k≠1, use this method to set n switch_i , which can make the critical speed range of the motor more reasonably divided and better meet the different speed requirements of the motor.

[0071] In one embodiment, setting a critical speed that matches the speed requirement further includes: when k≠1, selecting a coil from each tooth of the motor to connect in series to form a series branch containing A coils, and then A*k coils can form k series branches;

[0072] After all k series branches are connected in series, the effective value of the no-load back EMF of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ;

[0073] Select p series branches from k series branches, and connect the p series branches according to a preset series-parallel connection method to form a coil number of a in series for each phase i *The second line of A, where p is a positive integer and p < k, and a i is a positive integer and a i+1 < a i < p; after the second line operates, the effective value of the no-load back electromotive force of the corresponding motor reaches E m The speed at this time is the i-th critical speed, and the i-th critical speed is denoted as n switch_i ; where, n switch_i = k * n switch_1 / a i .

[0074] When k ≠ 1, this method can optimally divide the critical speed range of the motor, and the connection method of the windings in each critical speed range can have the highest matching degree with the different speed requirements of the motor.

[0075] In one embodiment, the first critical speed and the i-th critical speed successively divide [n min , n max into several adjacent critical speed ranges; where, n min represents the minimum value of the motor speed, and n max represents the maximum value of the motor speed; according to the critical speed range where the target speed of the motor is located, adjust the series-parallel connection method of the winding coils.

[0076] By successively dividing [n min , n max into several adjacent critical speed ranges using the first critical speed and the i-th critical speed, the series-parallel connection method of the winding coils in each critical speed range can be set more reasonably to meet the target speed of the motor.

[0077] The following further illustrates the winding coil connection method in combination with the winding coil connection examples of 4-pole 4-tooth, 6-pole 6-tooth, and 8-pole 8-tooth motors.

[0078] When it is a 4-pole 4-tooth motor, its grid-connected synchronous speed n s is 1500 rpm, and the speed range of the motor is 1000 rpm to 4500 rpm. Among them, rpm is the speed of the motor per minute. Assume that n represents the target speed, k is the number of coils on each tooth, n min represents the minimum value of the motor speed, and n max represents the maximum value of the motor speed.

[0079] See Figure 3 and Figure 4, select k = 1, there are 4 winding coils in total, switches ② and ③ can be controlled by single-pole double-position switches. switch_1 Set to 1500rpm, n switch_2 is 3000rpm, then:

[0080] Judgement min <n≤n switch_1 , that is, when the motor speed is greater than 1000rpm and less than or equal to 1500rpm, switch ① is closed, switches ② and ③ are opened, and all four coils are connected in series;

[0081] Judgement switch_1 <n≤n switch_2 , that is, when the motor speed is greater than 1500rpm and less than or equal to 3000rpm, switch ① is opened, switches ② and ③ are closed, and the four coils are first connected in series in pairs, and then the lines connected in series in pairs are connected in parallel to form two branches;

[0082] Judgement switch_2 <n<n max , that is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode.

[0083] See also Figure 5 and Figure 6 , select k = 3, there are 12 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. switch_1 Set to 1500rpm, n switch_2 is 4500rpm.

[0084] Determine the speed n min <n≤n switch_1 , that is, when the motor speed is greater than 1000rpm and less than or equal to 1500rpm, switches ① and ② are closed, switches ③, ④, ⑤ and ⑥ are opened, and all 12 coils are connected in series;

[0085] Determine the speed n switch_1 <n≤n switch_2 That is, when the motor speed is greater than 1500rpm and less than or equal to 4500rpm, switches ① and ② are opened, switches ③, ④, ⑤ and ⑥ are closed, and the 12 coils are first connected in series every 4 coils, and then the circuits after every 4 coils are connected in series are connected in parallel into 3 branches.

[0086] When it is a 6-pole 6-tooth motor, its grid-connected synchronous speed n s is 1000rpm, and the motor speed range is 900rpm~4500rpm. Among them, rpm is the motor speed per minute. Assume that n represents the target speed, n min Indicates the minimum value of the motor speed, nmax Indicates the maximum value of the motor speed.

[0087] See also Figure 7 and Figure 8 , select k = 1, there are 6 winding coils in total, switches ① and ② can be controlled by single-pole two-position switches, switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. switch_1 Set to 1000rpm, n switch_2 is 3000rpm, then:

[0088] Judgement min <n≤n switch_1 , that is, when the motor speed is greater than 900rpm and less than or equal to 1000rpm, switches ① and ② are closed, switches ③, ④, ⑤ and ⑥ are opened, and all 6 coils are connected in series;

[0089] Judgement switch_1 <n≤n switch_2 , that is, when the motor speed is greater than 1000rpm and less than or equal to 3000rpm, switches ① and ② are opened, switches ③, ④, ⑤ and ⑥ are closed, and the six coils are first connected in series in pairs, and then the two-by-two series circuits are connected in parallel into three branches;

[0090] Judgement switch_2 <n<n max , that is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode.

[0091] See also Fig. 9 and Fig.10 , select k = 3; there are 18 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. switch_1 Set to 1000rpm, n switch_2 is 3000rpm.

[0092] Determine the speed n min <n≤n switch_1 , that is, when the motor speed is greater than 900rpm and less than or equal to 1000rpm, switches ① and ② are closed, switches ③, ④, ⑤ and ⑥ are opened, and all 18 coils are connected in series;

[0093] Determine the speed n switch_1 <n≤n switch_2 That is, when the motor speed is greater than 1000rpm and less than or equal to 3000rpm, switches ① and ② are opened, switches ③, ④, ⑤ and ⑥ are closed, and the 18 coils are first connected in series every 6 coils, and then the circuits after every 6 coils are connected in series are connected in parallel into 3 branches.

[0094] Judgement switch_2<n<n max , that is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode.

[0095] When it is an 8-pole 8-tooth motor, its grid-connected synchronous speed n s is 750rpm, and the motor speed range is 700rpm~4500rpm. Among them, rpm is the motor speed per minute. Assume that n represents the target speed, n min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed.

[0096] See also Fig.11 and Fig.12 , select k = 1, there are 8 winding coils in total, switches ① and ③ can be controlled by single-pole two-position switches, switches ⑤ and ⑧ can be controlled by single-pole two-position switches, switches ④, ⑥, ⑦ and ⑨ can be controlled by single-pole four-position switches. switch_1 Set to 750rpm, n switch_2 1500rpm, n switch_3 is 3000rpm, then:

[0097] Judgement min <n≤n switch_1 , that is, when the motor speed is greater than 700rpm and less than or equal to 750rpm, switches ①, ② and ③ are closed, the remaining switches are open, and all 8 coils are connected in series;

[0098] Judgement switch_1 <n≤n switch_2 , that is, when the motor speed is greater than 750rpm and less than or equal to 1500rpm, switches ①, ③, ⑤ and ⑧ are closed, and the other switches are opened. The 8 coils are first connected in series in groups of four, and then the four series-connected lines are connected in parallel to form 2 branches;

[0099] Judgement switch_2 <n≤n switch_3 , that is, when the motor speed is greater than 1500rpm and less than or equal to 3000rpm, switches ④, ⑤, ⑥, ⑦, ⑧ and ⑨ are closed, switches ①, ② and ③ are opened, and the 8 coils are first connected in series in pairs, and then the lines connected in series in pairs are connected in parallel into 4 branches;

[0100] Judgement switch_3 <n<n max , that is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode.

[0101] See also Fig.13, select k = 6; there are 48 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. switch_1 Set to 750rpm, n switch_2 1500rpm, n switch_3 2250rpm, n switch_4 is 4500rpm, then:

[0102] Determine the speed n min <n≤n switch_1 , that is, when the motor speed is greater than 700rpm and less than or equal to 750rpm, switches ①, ②, ③, ④ and ⑤ are closed, the remaining switches are open, and all 48 coils are connected in series;

[0103] Determine the speed n switch_1 <n≤n switch_2 , that is, when the motor speed is greater than 750rpm and less than or equal to 1500rpm, switches ②, ④, ⑥, ⑦, ⑩, and Close, and the rest of the switches are open. The 48 coils are first connected in series every 8 to form 6 branches, then every 2 branches in the 6 branches are connected in parallel to form 3 branches, and finally the 3 branches are connected in series;

[0104] Determine the speed n switch_2 <n≤n switch_3 , that is, when the motor speed is greater than 1500rpm and less than or equal to 2250rpm, switches ③, ⑥, ⑦, ⑧, ⑨, and Close, and the rest of the switches are open. 48 coils are first connected in series every 8 to form 6 branches, then every 3 branches in the 6 branches are connected in parallel to form 2 branches, and finally the 2 branches are connected in series;

[0105] Determine the speed n switch_3 <n≤n switch_4 That is, when the motor speed is greater than 2250rpm and less than or equal to 4500rpm, switches ①, ②, ③, ④ and ⑤ are opened, and the remaining switches are closed. The 48 coils are first connected in series every 8, and then the circuits after every 8 coils are connected in series are connected in parallel.

[0106] Example 2

[0107] In order to better explain the motor speed regulation method, Fig.14 A flow chart of a motor speed regulation method provided in Embodiment 2 of the present invention;

[0108] Step 301: when the target speed is greater than the minimum value of the motor speed and less than or equal to the maximum value of the critical speed, the series-parallel connection mode of the winding coils is set by the above-mentioned motor winding coil connection method to adjust the speed of the motor;

[0109] When the target speed is greater than the minimum value of the motor speed and less than or equal to the maximum value of the critical speed, a winding coil connection method with a matching critical speed range can make the motor speed reach the target speed. Therefore, a winding coil connection method corresponding to the target speed of the motor can be used to reduce the no-load back electromotive force of the motor.

[0110] Step 302: When the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed, a magnetic field weakening speed regulation method is adopted.

[0111] When the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed, there is no available winding coil connection method to make the motor speed reach the target speed, so it is necessary to use a weak magnetic speed regulation method to make the motor speed reach the target speed.

[0112] The speed regulation method is further explained below with reference to the speed regulation examples of motors with 4 poles and 4 teeth, 6 poles and 6 teeth, and 8 poles and 8 teeth.

[0113] When it is a 4-pole 4-tooth motor, the motor speed range is 1000rpm~4500rpm. Among them, rpm is the motor speed per minute. Assume that n represents the target speed, k is the number of coils on each tooth, and n is min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed.

[0114] Select k = 1, there are 4 winding coils, switches ② and ③ can be controlled by single-pole double-position switches. Assume that the maximum value of the critical speed n switch_max is 3000rpm, then:

[0115] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 1000rpm and less than or equal to 3000rpm, select the winding coil series-parallel connection mode that matches the motor target speed so that the motor speed reaches the target speed;

[0116] Judgement switch_max <n<n max That is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode, and weak magnetic speed regulation is required to make the motor speed reach the target speed.

[0117] Select k = 3, there are 12 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. Assume that the maximum value of the critical speed n switch_max is 4500rpm, then:

[0118] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 1000rpm and less than or equal to 4500rpm, a winding coil series-parallel connection mode matching the motor target speed is selected to make the motor speed reach the target speed.

[0119] When it is a 6-pole 6-tooth motor, the motor speed range is 900rpm~4500rpm. Among them, rpm is the motor speed per minute. Then:

[0120] Select k = 1, there are 6 winding coils, switches ① and ② can be controlled by single-pole two-position switches, switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. Assume that the maximum value of the critical speed n switch-_max is 3000rpm, then:

[0121] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 900rpm and less than or equal to 3000rpm, a winding coil series-parallel connection mode matching the motor target speed is selected to make the motor speed reach the target speed;

[0122] Judgement switch_max <n<n max That is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode, and weak magnetic speed regulation is required to make the motor speed reach the target speed.

[0123] Select k = 3; there are 18 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. Assume that the maximum value of the critical speed n switch_max is 4500rpm, then:

[0124] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 900rpm and less than or equal to 4500rpm, a winding coil series-parallel connection mode matching the motor target speed is selected to make the motor speed reach the target speed;

[0125] When it is an 8-pole 8-tooth motor, the motor speed range is 700rpm~4500rpm. Among them, rpm is the motor speed per minute. Assume that n represents the target speed, n min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed.

[0126] Select k = 1, there are 8 winding coils in total, switches ① and ③ can be controlled by single-pole two-position switches, switches ⑤ and ⑧ can be controlled by single-pole two-position switches, switches ④, ⑥, ⑦ and ⑨ can be controlled by single-pole four-position switches. Assume that the maximum value of the critical speed n switch_max is 3000rpm, then:

[0127] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 700rpm and less than or equal to 3000rpm, select the winding coil series-parallel connection mode that matches the motor target speed so that the motor speed reaches the target speed;

[0128] Judgement switch_max <n<n max That is, when the motor speed is greater than 3000rpm and less than 4500rpm, there is no available winding coil series-parallel connection mode, and weak magnetic speed regulation is required to make the motor speed reach the target speed.

[0129] Select k = 6; there are 48 winding coils in total, switches ① and ② are controlled by single-pole two-position switches, and switches ③, ④, ⑤ and ⑥ can be controlled by single-pole four-position switches. Assume that the maximum value of the critical speed n switch_max is 4500rpm, then:

[0130] Judgement min <n≤n switch_max , that is, when the motor speed is greater than 700rpm and less than or equal to 4500rpm, a winding coil series-parallel connection mode matching the motor target speed is selected to make the motor speed reach the target speed.

[0131] The motor can achieve stepless speed regulation: when n min <n≤n switch_1 , the motor can reach the required load in different series-parallel connection modes of the winding coils, and the no-load back EMF does not exceed the allowable range. However, since the motor has higher operating efficiency in the mode where all coils are connected in series, the motor selects the mode where all coils are connected in series; when n switch_1 <n≤n switch_i , the motor's no-load back EMF will exceed the limit in the current winding coil series-parallel connection mode. When the motor cannot reach the required load, it is necessary to switch to other winding coil series-parallel connection modes to meet the motor's required load. switch_i <n≤n max When there is no feasible winding coil series-parallel connection mode to meet the required load of the motor, it is necessary to use the weak magnetic speed control method in this speed range to meet the required load of the motor. min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed, nswitch_1 represents the first critical speed, n switch_i represents the i-th critical speed, i is a positive integer greater than 1, and n represents the target speed of the motor.

[0132] The motor runs in step-by-step speed regulation: Assume that the motor speed can be divided into x levels when it is not stopped, and the x-level speeds are recorded as n v_1 , n v_2 , ... n v_x And n v_1 ≥n min , n v_x ≤n max . v_1 , n v_2 , ... n v_x The set composed of is denoted as V. Assume n v_j is an element in the set V, if there exists n v_j =n switch_i or v_j =n switch_1 , then when the motor speed is greater than n v_j When n is reached, the motor switches to the matching winding coil series-parallel connection mode; if n does not exist v_j =n switch_i or v_j =n switch_1 , then find the speed n in the set V v_a , if there exists n v_a <n switch_i And n v_a+1 >n switch_i Or there is n v_a <n switch_1 And n v_a+1 >n switch_1 When, n switch_i It cannot be the maximum critical speed. When the motor speed is greater than n v_a When n switch_i <n v_a ≤n max When there is no feasible winding coil series-parallel connection mode to meet the required load of the motor, it is necessary to use the weak magnetic speed control method in this speed range to meet the required load of the motor. min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed, n switch_1 represents the first critical speed, n switch_i represents the i-th critical speed, a, x, j are all positive integers, and i is a positive integer greater than 1.

[0133] Example 3

[0134] Corresponding to the aforementioned embodiment of the method for connecting the winding coils of a motor, the present invention also provides an embodiment of the device for connecting the winding coils of a motor.

[0135] Fig.15 A schematic diagram of a module of a winding coil connection device of a motor provided in Embodiment 3 of the present invention, wherein the winding coil connection device comprises:

[0136] A setting module, used to set a critical speed matching the speed requirement according to different speed requirements when the motor is running; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum speed of the motor;

[0137] Determination module: used to determine the series-parallel connection mode of the winding coil according to the critical speed and the target speed of the motor.

[0138] Example 4

[0139] Corresponding to the aforementioned embodiment of the motor speed regulation method, the present invention also provides an embodiment of the motor speed regulation device.

[0140] Fig.16 A schematic diagram of a module of a motor speed regulating device provided in Embodiment 4 of the present invention, the device comprising the winding coil connection device of the motor;

[0141] A regulating module, used for setting the series-parallel connection mode of the winding coils by any of the above-mentioned winding coil connection methods of the motor to regulate the speed of the motor when the target speed is greater than the minimum speed of the motor and less than or equal to the maximum speed of the critical speed;

[0142] A module is used to adopt a magnetic field weakening speed regulation mode when the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed.

[0143] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of the present invention. Ordinary technicians in this field can understand and implement it without paying creative work.

[0144] Example 5

[0145] In order to illustrate the structure of the motor, this embodiment provides a motor. Preferably, the motor is a single-phase permanent magnet motor, and the motor includes a winding composed of a plurality of coils, a winding coil connecting device such as the above-mentioned winding coil connecting device, and a speed regulating device of the motor such as the above-mentioned motor; the motor has A poles and A teeth, and each tooth is wound with k coils, wherein A and k are both positive integers. Fig.17 This is a schematic diagram of the structure of a motor provided in Example 5 of the present invention.

[0146] The motor is a 6-stage 6-tooth motor, with k coils wound around each tooth. Fig.17 Coil 1, coil 2, ... coil k represent k coils wound on the tooth 171, where k is a positive integer. Preferably, the number of turns of each coil on the tooth is the same.

[0147] The motor can realize any of the above-mentioned motor winding coil connection methods and motor speed regulation methods, and can more flexibly switch the series-parallel connection mode of the coil and the speed regulation mode according to the target speed of the motor to meet the working requirements of the motor.

[0148] Example 6

[0149] An embodiment of the present invention further provides a computer-readable medium having a computer program stored thereon, and when the program is executed by a processor, the method provided by any of the above embodiments is implemented.

[0150] The readable medium may include but is not limited to: a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device or any suitable combination thereof.

[0151] In a possible implementation manner, the embodiment of the present invention may also be implemented in the form of a program product, which includes a program code. When the program product is run on a terminal device, the program code is used to enable the terminal device to execute a method for implementing any of the above embodiments.

[0152] The program code for executing the present invention may be written in any combination of one or more programming languages, and may be executed entirely on a user device, partially on a user device, as an independent software package, partially on a user device and partially on a remote device, or entirely on a remote device.

[0153] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A method for connecting a winding coil of a motor, characterized in that: Applied to a single-phase permanent magnet motor, the winding coil connection method includes: According to different speed requirements when the motor is running, a critical speed matching the speed requirement is set; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum value of the motor speed; The series-parallel connection mode of the winding coils is determined according to the critical speed and the target speed of the motor.

2. The method for connecting the winding coils of a motor according to claim 1, characterized in that: The setting of a critical speed matching the speed requirement includes: After all winding coils are connected in series, the effective value of the no-load back EMF of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ; Among them, E m Indicates the effective value of the no-load back EMF of the motor.

3. The method for connecting the winding coils of a motor according to claim 2, characterized in that: The motor has A poles and A teeth, and each tooth is wound with k coils, where A and k are both positive integers; The setting of the critical speed matching the speed requirement further includes: When k = 1, the winding current is i The coils are first connected in series to form a branch circuit, forming a total of m i series branches, and then connect the m i After the branches are connected in parallel, the corresponding motor's no-load back EMF reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i ; Among them, m i represents the factors of A other than 1, and i represents a positive integer greater than 1; and / or, When k≠1, q coils are selected from the A*k coils of the winding, and the q coils are connected in a predetermined series-parallel manner to form a winding having a number of x coils connected in series per phase. i The first line of; wherein, q is a multiple of A and q≤A*k, x i is a positive integer; After the first circuit is operated, the corresponding motor's no-load back EMF effective value reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i .

4. The method for connecting the winding coils of a motor according to claim 3, characterized in that: The setting of the critical speed matching the speed requirement further includes: When k≠1, one coil is selected from each tooth of the motor for series connection to form a series branch containing A coils, and then A*k coils can form k series branches; After all the k series branches are connected in series, the effective value of the no-load back EMF of the corresponding motor reaches E m The speed at which the speed is the first critical speed, and the first critical speed is recorded as n switch_1 ; Select p series branches from the k series branches, connect the p series branches according to a preset series-parallel connection method, and form a number of coils in series per phase. i * The second line of A, p is a positive integer and p<k, a i is a positive integer and a i+1 i <p;​ After the second circuit is operated, the corresponding motor's no-load back EMF effective value reaches E m The speed at which the critical speed is i is the i-th critical speed, and the i-th critical speed is recorded as n switch_i ; Among them, n switch_i =k*n switch_1 / a i .

5. The method for connecting the winding coils of a motor according to claim 3, characterized in that: The first critical speed and the i-th critical speed are respectively [n min , n max ] is divided into several adjacent critical speed intervals; where n min Indicates the minimum value of the motor speed, n max Indicates the maximum value of the motor speed; The series-parallel connection mode of the winding coils is adjusted according to the critical speed range in which the target speed of the motor is located.

6. A method for regulating the speed of a motor, characterized in that: The speed regulation method comprises: When the target speed is greater than the minimum value of the motor speed and less than or equal to the maximum value of the critical speed, the series-parallel connection mode of the winding coils is set by the winding coil connection method of the motor according to any one of claims 1 to 5 to adjust the speed of the motor; When the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed, a magnetic field weakening speed regulation mode is adopted.

7. A winding coil connection device for a motor, characterized in that: The winding coil connection device comprises: A setting module, used to set a critical speed matching the speed requirement according to different speed requirements when the motor is running; wherein the minimum value of the critical speed is greater than or equal to the grid-connected synchronous speed of the motor, and the maximum value of the critical speed is less than or equal to the maximum speed of the motor; Determination module: used to determine the series-parallel connection mode of the winding coil according to the critical speed and the target speed of the motor.

8. A speed regulating device for a motor, characterized in that: The device comprises the winding coil connection device of the motor according to claim 7; A regulating module, used for setting the series-parallel connection mode of the winding coils by the winding coil connection method of the motor according to any one of claims 1 to 5 to regulate the speed of the motor when the target speed is greater than the minimum speed of the motor and less than or equal to the maximum speed of the critical speed; A module is used to adopt a magnetic field weakening speed regulation mode when the target speed is greater than the maximum value of the critical speed and less than the maximum value of the motor speed.

9. A motor, characterized in that: The motor comprises a winding composed of a plurality of coils, a winding coil connection device as claimed in claim 7 and / or a motor speed regulating device as claimed in claim 8; The motor has A poles and A teeth, and each tooth is wound with k coils, wherein A and k are both positive integers.

10. A computer readable medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for connecting the winding coils of a motor described in any one of claims 1 to 5 and / or the method for regulating the speed of a motor described in claim 6 are implemented.

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