Harmonic self-starting permanent magnet synchronous motor

Abstract

This invention discloses a harmonic self-starting permanent magnet synchronous motor, which utilizes rotor winding coils with different pitches to generate induced electromotive forces of different magnitudes and directions in magnetic fields with different pole pairs generated by the stator. This is equivalent to connecting an additional resistor, increasing the rotor resistance during motor startup and thus providing good starting performance. During normal operation, by changing the stator winding connection, the stator magnetomotive force harmonics are canceled, and the motor returns to a conventional motor state. At this time, the rotor resistance returns to normal, which is equivalent to removing the additional resistor, resulting in high operating efficiency. Therefore, by using rotor windings, it is possible to increase the starting torque of the motor without an additional starting resistor, while maintaining the structural characteristics of the motor without slip rings and brushes.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and specifically to a harmonic self-starting permanent magnet synchronous motor. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) have advantages such as high efficiency, high power factor, and stable operation, and are widely used in industrial transmission, new energy vehicles, and home appliances. However, traditional PMSMs suffer from starting difficulties, especially under heavy-load starting scenarios, where their starting torque is insufficient and the starting current is too large, making it difficult to meet the requirements of actual working conditions.

[0003] Existing technologies often involve adding slip rings and brushes to the rotor side and inserting a starting resistor in series. This increases the rotor resistance to improve starting torque and suppress starting current. However, the presence of slip rings and brushes not only increases the structural complexity of the motor and raises maintenance costs, but also makes it prone to wear, poor contact, and other faults, reducing the reliability of motor operation. At the same time, the removal and activation of the additional starting resistor requires complex control circuitry, further increasing the overall cost and failure rate of the system. Traditional brushless starting schemes often suffer from the drawback of not being able to balance starting performance and operating efficiency. The starting winding generates additional losses during normal motor operation, reducing the motor's operating efficiency. If the starting winding needs to be removed, a switching device must be added, which cannot fundamentally simplify the motor structure. Summary of the Invention

[0004] This invention proposes a harmonic self-starting permanent magnet synchronous motor to solve the technical problems mentioned in the background.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A harmonic self-starting permanent magnet synchronous motor of the present invention includes a stator and a rotor. The stator is provided with two relatively independent sets of windings, namely a starting winding and an auxiliary winding. The rotor is provided with a set of permanent magnets and two sets of rotor windings. Both the starting winding and the auxiliary winding produce a pole pair number of... The fundamental magnetic field simultaneously generates a pole pair number of , And the rotation direction of the harmonic magnetic field is the same as that of the fundamental magnetic field; Both sets of rotor windings are in accordance with opposite pole The phases are arranged in a regular pattern, consisting of the first rotor winding and the second rotor winding. The coil pitch of the first rotor winding is as follows: The poles are arranged with corresponding full or short pole pitches, and the second rotor winding coil pitch is arranged according to... The number of slots corresponding to the polar harmonic is twice the number of slots with the same pitch. The first rotor winding's first... The first phase Branch, and the second rotor winding's first The first phase Branch circuits are connected in parallel, when the two branches are generated by the stator. When the fundamental magnetic field is applied, the phase difference between the axes of the magnetic fields induced by the two branches is approximately... Electrical angle, and the second rotor winding's first The first phase Branch circuit, located in the stator generation In a polar magnetic field, the vector summation value of the induced electromotive force is equal to zero; The rotor is arranged with a set of pole pairs. Permanent magnets.

[0006] Preferably, when the motor starts, the starting winding on the stator is connected to the power grid, and the starting winding generates a number of pole pairs. The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

[0007] Preferably, when the auxiliary winding on the motor stator is connected to the power grid, the auxiliary winding generates a pole pair number of... The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

[0008] Preferably, the The , .

[0009] Preferably, the motor starting winding generates The polar magnetic field generated by the auxiliary winding For polar magnetic fields, in phase difference Electrical angle refers to the spatially in-phase magnetic fields that are superimposed within the motor.

[0010] Preferably, the motor starting winding generates , The polar harmonic magnetic field generated by the auxiliary winding , For polar harmonic magnetic fields, the phase difference is respectively Electrical angle refers to the spatial phase opposition within the motor, where the magnetic fields cancel each other out.

[0011] Preferably, when the motor starting winding and auxiliary winding are simultaneously connected to the power grid, the combined spatial magnetic field generated by the starting winding and auxiliary winding is: Opposite magnetic field.

[0012] Preferably, the motor is for For each pole, both sets of rotor windings have high winding coefficients, and when both sets of rotor windings are in the stator generation... In the polar magnetic field, both sets of rotor windings have strong electromagnetic coupling with the stator side.

[0013] Preferably, the motor is for For each pole, the first rotor winding has a high winding coefficient, while the second rotor winding has a winding coefficient close to zero. When both sets of rotor windings are in the stator generation... In a polar magnetic field, the electromagnetic coupling between the first rotor winding and the stator side is strong, while the electromagnetic coupling between the second rotor winding and the stator side is weak, meaning that the second rotor winding is equivalent to a section of resistance.

[0014] Preferably, the first rotor winding of the motor is... The first phase Side road, for Branch, and the second rotor winding's first The first phase Branch circuits are connected in parallel, when the two branches are generated by the stator. In a polar magnetic field, it is equivalent to The branch circuit is connected in series with a resistor.

[0015] As can be seen from the above technical solution, the present invention provides a harmonic self-starting permanent magnet synchronous motor. Compared with the prior art, the present invention has the following advantages: by utilizing the harmonic magnetic field characteristics of the stator winding and the impedance change characteristics of the rotor double-pitch winding, a brushless and resistance-free solution is achieved to increase starting resistance and reduce running resistance: during startup, only the starting winding works, and the rotor winding is effectively resisted to increase starting torque and suppress starting current; during normal operation, the auxiliary winding is engaged to cancel the stator harmonic magnetic field, and the rotor winding returns to a low-resistance state, ensuring the motor's operating efficiency. At the same time, synchronous operation is achieved by relying on permanent magnets, combining the reliability of asynchronous starting with the high efficiency of synchronous operation. Attached Figure Description

[0016] Figure 1 This is a diagram showing the slot number phase and the grouping of the three-phase windings when the stator Zs=36 and p1=4 in this invention. Figure 2 This is a phase diagram of the slot number when stator Zs=36 and p2=3, and a schematic diagram of the three-phase winding grouped according to p1=4 with p2=3 pole pairs of the present invention. Figure 3This is a schematic diagram showing the grouping of the starting winding and auxiliary winding when the stator Zs=36, p1=4, p2=3 of the present invention. Figure 4 This invention provides the grouping of each phase starting winding according to star and delta configurations when stator Zs=36, p1=4, p2=3, and the phase diagram of slot number under p1=4 pole pair. Figure 5 This is the stator winding wiring diagram for the present invention when stator Zs=36, p1=4, p2=3.

[0017] Figure 6 This is a diagram showing the proportion of the fundamental and harmonic magnetic fields and magnetomotive forces after the stator starting winding of the present invention is connected to the power grid when stator Zs=36, p1=4, p2=3. Figure 7 The stator starting winding and auxiliary winding are connected to the power grid simultaneously when the stator Zs=36, p1=4, p2=3, according to the present invention, stator winding phase diagram. Figure 8 This is the slot phase diagram of the rotor winding with 4 pole pairs when the rotor Zr=32 and p1=4. Figure 9 This is the rotor winding wiring diagram when the rotor Zr=32 of the present invention; Figure 10 This shows the distribution of rotor winding unit groups in the rotor slots when the rotor Zr=32 according to the present invention; Figure 11 When the rotor Zr=32 in this invention, the rotor winding is in Wiring diagram of the winding unit group in the magnetic field of the counter-polar stator; Figure 12 When the rotor Zr=32 in this invention, the rotor winding is in Equivalent circuit in the magnetic field of the polar stator; Figure 13 When the rotor Zr=32 in this invention, the rotor winding is in The equivalent circuit in the polar stator magnetic field. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0019] This embodiment of a harmonic self-starting permanent magnet synchronous motor includes a stator and a rotor. The stator is provided with two relatively independent sets of windings, namely a starting winding and an auxiliary winding. The rotor is provided with a set of permanent magnets and two sets of rotor windings. Both the starting winding and the auxiliary winding produce a pole pair number of The fundamental magnetic field simultaneously generates a pole pair number of , And the rotation direction of the harmonic magnetic field is the same as that of the fundamental magnetic field; Both sets of rotor windings are in accordance with opposite pole The phases are arranged in a regular pattern, consisting of the first rotor winding and the second rotor winding. The coil pitch of the first rotor winding is as follows: The poles are arranged with corresponding full or short pole pitches, and the second rotor winding coil pitch is arranged according to... The number of slots corresponding to the polar harmonic is twice the number of slots with the same pitch. The first rotor winding's first... The first phase Branch, and the second rotor winding's first The first phase Branch circuits are connected in parallel, when the two branches are generated by the stator. When the fundamental magnetic field is applied, the phase difference between the axes of the magnetic fields induced by the two branches is approximately... Electrical angle, and the second rotor winding's first The first phase Branch circuit, located in the stator generation When in a polar magnetic field, the vector summation value of the induced electromotive force is equal to zero. , , ); The rotor is arranged with a set of pole pairs. Permanent magnets.

[0020] When the motor starts, the starting winding on the stator is connected to the power grid, and the starting winding generates a pole pair number of... The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

[0021] When the auxiliary winding on the motor stator is connected to the power grid, the auxiliary winding generates a pole pair number of... The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

[0022] The starting winding of the motor generates The polar magnetic field generated by the auxiliary winding For polar magnetic fields, in phase difference Electrical angle refers to the spatially in-phase magnetic fields that are superimposed within the motor.

[0023] The starting winding of the motor generates , The polar harmonic magnetic field generated by the auxiliary winding , For polar harmonic magnetic fields, the phase difference is respectively Electrical angle refers to the spatial phase opposition within the motor, where the magnetic fields cancel each other out.

[0024] When the starting winding and auxiliary winding of the motor are connected to the power grid simultaneously, the combined spatial magnetic field generated by the starting winding and auxiliary winding is: Opposite magnetic field.

[0025] Motor for For each pole, both sets of rotor windings have high winding coefficients, and when both sets of rotor windings are in the stator generation... In the polar magnetic field, both sets of rotor windings have strong electromagnetic coupling with the stator side.

[0026] Motor for For each pole, the first rotor winding has a high winding coefficient, while the second rotor winding has a winding coefficient close to zero. When both sets of rotor windings are in the stator generation... In a polar magnetic field, the electromagnetic coupling between the first rotor winding and the stator side is strong, while the electromagnetic coupling between the second rotor winding and the stator side is weak, meaning that the second rotor winding is equivalent to a section of resistance.

[0027] The first rotor winding of the motor The first phase Side road, for Branch, and the second rotor winding's first The first phase Branch circuits are connected in parallel, when the two branches are generated by the stator. In a polar magnetic field, it is equivalent to The branch circuit is connected in series with a resistor.

[0028] In practical applications, this embodiment selects a unit with a power rating of 15kW, 36 stator slots, and a permanent magnet pole pair number of... The stator and rotor structural parameters of the harmonic self-starting permanent magnet synchronous motor are as follows: The stator winding parameters are as follows: like Figure 1 As shown, the stator winding first follows... The slot numbers assigned to the three phases of the extremely regular 60° phase band winding; like Figure 2 As shown, the slot numbers occupied by the above three phases are arranged according to the main harmonics. A three-phase slot numbering diagram arranged with opposite phases; to obtain the scheme with the strongest main harmonics, it should be in A 4-3 B 4-3 C 4-3 The auxiliary windings on the three-phase sequence are designed with the slot numbers of the three phases to make the slot number allocation most concentrated, and to... The primary harmonics are 120° apart.

[0029] like Figure 3 As shown, the starting winding and auxiliary winding are grouped together; the A-phase windings 1, 2, and -33 within the thick solid line frame are connected in series to form the A-phase auxiliary winding A. F The B-phase windings 5, -36, and 31 within the thick solid line frame are connected in series to form the B-phase auxiliary winding B. F The C-phase windings -3, 34, and 35 within the thick solid line frame are connected in series to form the C-phase auxiliary winding C. F The remaining winding coils in the A-phase winding group constitute the A-phase starting winding, namely, coils 28, 29, -24, 19, 20, -15, 10, 11, and -6 form the A-phase starting winding A. Q The starting windings of phases B and C Q C Q They are: B Q Phase starting windings 32, -27, 22, -18, 13, 14, -9, 4, C Q Phase starting windings: -30, 25, 26, -21, 16, 17, -12, 7, 8.

[0030] like Figure 4 As shown, the starting windings of phases A, B, and C are in The slot number phase diagram for the pole. To improve the starting torque of the motor, the starting windings of each phase are divided into two groups according to their phase, namely, A. Q△ Phase, B Q△ Phase, C Q△ A group of phases, A QY Phase, B QY Phase, C QY A group. In At the extreme, A Q△ The winding centerline leads by A QY The winding centerline is 30° electrical angle. For example... Figure 5 The stator winding wiring diagram is shown below. When the motor starts, switch K1 is closed and K2 remains open. The distribution coefficient of the stator starting winding is...

[0031] However, when using the ordinary uniform distribution connection method... Compared with the ordinary connection method, the distribution coefficient of the starting winding of the Y-Δ connection method is improved. .

[0032] like Figure 6 The starting winding and auxiliary winding shown both use double-layer short-pitch windings, with a winding phase number of... The pitch of both the starting winding and the auxiliary winding is ,correspond For extremely short pitch, when the starting winding operates alone, in addition to generating In addition to the polar fundamental magnetic field, it can also generate opposite pole, The proportion of the fundamental and harmonic magnetic fields of the opposite poles after the stator starting winding is connected to the power grid.

[0033] like Figure 7 As shown, after the starting process is completed, K2 closes, and the auxiliary winding is connected to the power grid. The polar magnetic field is superimposed in phase with the starting winding. opposite pole, The polar harmonic magnetic field cancels out with the starting winding in opposite phase, resulting in a pure stator composite magnetic field. The fundamental magnetic field. With the stator starting winding and auxiliary winding simultaneously connected to the power grid, it's easy to see that the phase distribution of each coil constituting each phase winding in the stator is the same. When the poles are aligned, the three-phase windings lag by 120° electrical degrees in sequence, and there is no reverse fundamental magnetic field, which is exactly the same as the performance of a normal 4-pole motor.

[0034] The rotor winding parameters are as follows: like Figure 8 As shown, the rotor has 32 slots, and both sets of wound windings are arranged in a 2-phase regular phase band. The diagram shows the slot number of the 32 slots and 4 pole pairs, as well as the phase diagram of the grouping of the two sets of rotor windings. The number of pole pairs is consistent with that of a permanent magnet. Corresponding to the number of pole pairs of the main harmonics of the stator; Depend on Figure 8 It can be seen that the first phase of the first set of rotor windings consists of 8 coil groups, namely coil groups 1 and 2, coil groups -5 and -6, coil groups 9 and 10, coil groups -13 and -14, coil groups 17 and 18, coil groups -21 and -22, coil groups 25 and 26, and coil groups -29 and -30. Under 4 pole pairs, these 8 coil groups have the same phase and amplitude. Similarly, the 8 coil groups constituting the second phase of the first set of rotor windings also have the same phase and amplitude, and the amplitude is the same as the amplitude of the induced electromotive force of each coil group in the first phase winding, but the phase lags behind the induced electromotive force of each coil group in the first phase by 90° electrical angle.

[0035] Similarly, it is not difficult to prove that the amplitude of the induced electromotive force of each coil group in the first and second phases of the second set of rotor windings is also equal; in terms of phase, the induced electromotive force of each coil group in the second phase lags behind the induced electromotive force of each coil group in the first phase by 90° electrical angle.

[0036] like Figure 9 The rotor two-winding connection diagram shown is for ensuring The rotor has a high winding utilization rate when the polar fundamental wave is applied. Here, the pitch of the first set of rotor windings is taken as... opposite poles Full pitch, the second set of rotor winding pitch is taken as Rounding down twice the number of slots (16 / 3 slots) to 32 / 3 slots, select... When the second winding uses an 11-slot pitch, in In a polar magnetic field, the second winding branch is approximately equivalent to a pure resistance, increasing the rotor's equivalent resistance to 5-6 times its original value, thus meeting the heavy-load starting requirements. To obtain a larger starting torque, the number of turns is taken as follows. , .

[0037] Figure 9 In the diagram, a1 and a2 are connected together. Taking the potential at point a1 as the reference point, we have: Suppose that the connection between b1 and b2 is broken, and the connection between c1 and c2, ..., h1 and h2 is also broken.

[0038] When the rotor winding is in When in the stator magnetic field, the induced electromotive force generated in the first coil group of the first phase of the first set of rotor windings, namely coils 1 and 2, is:

[0039]

[0040] but

[0041] In the formula, It represents the effective value of the electromotive force induced in a single conductor of the rotor within the four pole magnetic field of the stator.

[0042] Similarly, it is not difficult to prove that the amplitude and phase of the induced electromotive force generated by the other 7 coil groups are equal to this.

[0043] Assume the leakage impedance of each turn of the coil is Then, from the Thevenin equivalent circuit, we can see that:

[0044] In the formula, When the rotor winding is in The effective value of the induced current in the first phase winding of the first set of rotor windings when in the magnetic field of the polar stator; Then the position of point b1 is

[0045] The induced electromotive force generated in the stator magnetic field by the first coil group of the first phase of the second rotor winding, namely coils -29 and -30, is:

[0046]

[0047] but

[0048] Similarly, it is not difficult to prove that the amplitude and phase of the induced electromotive force generated by the other 7 coil groups are equal to this.

[0049] Considering that the leakage impedance at the rotor winding ends is relatively small, and ignoring the differences at the rotor coil ends, we can still assume that the leakage impedance of each coil turn is constant. Then, from the Thevenin equivalent circuit, we can see that:

[0050] In the formula, When the rotor winding is in The effective value of the induced current in the first phase winding of the second set of rotor windings when in the magnetic field of the polar stator; Then the location of point b2 is

[0051] Obviously, Connecting b1 and b2 with a connecting wire does not affect the external characteristics of the rotor circuit. Similarly, connecting c1 and c2... ... The presence of the connection line between h1 and h2 does not affect the external characteristics of the rotor circuit; and and They are approximately equal, and both sets of rotor windings have good electromagnetic coupling with the stator magnetic field.

[0052] according to Figure 9 As shown in the diagram, one branch of the first rotor winding is connected in parallel with one branch of the second rotor winding, and then the two ends are short-circuited to form a winding unit group. Figure 10 The distribution of winding unit groups in the rotor slots is given.

[0053] It is easy to see that the two branches are close in phase under the four pole pairs, and after the magnetic fields are combined, they interact with the stator's four pole pairs magnetic field to generate electromagnetic torque. Typically... Much larger The combined magnetic field axis of the two branches is closer to the central axis of coils 1 and 2. When the rotor winding is in When in the magnetic field of the polar stator, the wiring diagram and equivalent circuit of the unit winding are as follows: Figure 11 as well as Figure 12 As shown.

[0054] When the rotor winding is in When in the magnetic field of the polar stator, the wiring diagram and equivalent circuit of the winding unit group are as follows: Figure 13 As shown. The induced electromotive force generated by each turn of coils 1, 2, -29, and -30 are respectively

[0055]

[0056] but

[0057] In the formula, It represents the effective value of the electromotive force induced in a single conductor of the rotor within the three-pole magnetic field of the stator.

[0058]

[0059]

[0060] but

[0061] Compare the induced electromotive force generated by each one-turn coil in the three-pair magnetic field. Much larger The coil groups -29 and -30 are approximately equivalent to a series of resistors.

[0062] Figure 9 In the first set of rotor windings, the vector sum of the electromotive forces induced in each branch by the three pairs of pole magnetic fields is zero. Similarly, the vector sum of the electromotive forces induced in each branch of the second set of rotor windings by the three pairs of pole magnetic fields is also zero. However, since there are connecting lines between b1 and b2, c1 and c2, and h1 and h2, and... Much larger Then, coil groups 1 and 2 form a loop current with coil groups -29 and -30. Since coil groups -29 and -30 are approximately equivalent to a series of resistors at this time, it is equivalent to a resistor being inserted into the rotor circuit, which improves the power factor of the rotor circuit.

[0063] The working condition verification is as follows: Starting phase: Only the stator starting winding is connected to the 380V power frequency grid. The stator generates a 4-pole fundamental wave and a 3-pole and a 2-pole harmonic magnetic field. The rotor parallel winding is effectively resisted under the 3-pole harmonic magnetic field. The motor starts asynchronously. The measured starting torque reaches twice the rated torque, and the starting current is limited to three times the rated current. Operation phase: When the motor speed increases to 90% of the synchronous speed, the auxiliary winding is connected to the grid, the stator harmonic magnetic field is canceled, the equivalent resistance of the rotor winding is restored to the normal value, and the motor enters the synchronous operation state by relying on the permanent magnet. The measured operating efficiency reaches 95.2%, the power factor is 0.98, and there is no additional winding loss.

[0064] In summary, the harmonic self-starting permanent magnet synchronous motor of the present invention achieves efficient self-starting without brush or additional resistance by switching the stator harmonic magnetic field and adaptively changing the impedance of the rotor double-pitch winding. It has both excellent starting performance and operating efficiency, and has broad application prospects in industrial transmission, new energy, home appliances and other fields.

[0065] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0066] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0067] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A harmonic self-starting permanent magnet synchronous motor, characterized in that, It includes a stator and a rotor. The stator has two relatively independent sets of windings, namely a starting winding and an auxiliary winding. The rotor has one set of permanent magnets and two sets of rotor windings. Both the starting winding and the auxiliary winding produce a pole pair number of... The fundamental magnetic field, and produces a pole pair number of , And the rotation direction of the harmonic magnetic field is the same as that of the fundamental magnetic field; Both sets of rotor windings are in accordance with opposite pole The phases are arranged in a regular pattern, consisting of the first rotor winding and the second rotor winding. The coil pitch of the first rotor winding is as follows: The poles are arranged with corresponding full or short pole pitches, and the second rotor winding coil pitch is arranged according to... The arrangement of slots with twice the total pitch corresponding to the polar harmonics, the first rotor winding's first... Phase 1 Branch, and the second rotor winding's first Phase 1 Branches are connected in parallel, when the branch of the first rotor winding and the branch of the second rotor winding are in the stator generation When the fundamental magnetic field is applied, the phase difference between the central axes of the magnetic fields induced by the branches of the first and second rotor windings is [missing information]. Electrical angle, and the second rotor winding's first Phase 1 Branch circuit, located in the stator generation In a polar magnetic field, the vector summation value of the induced electromotive force is equal to zero; the starting winding of the motor generates... , The polar harmonic magnetic field generated by the auxiliary winding , For polar harmonic magnetic fields, the phase difference is respectively Electrical angle refers to the spatial phase opposition within the motor, where the magnetic fields cancel each other out.

2. The harmonic self-starting permanent magnet synchronous motor according to claim 1, characterized in that: When the motor starts, the starting winding on the stator is connected to the power grid, and the starting winding generates a pole pair number of... The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

3. The harmonic self-starting permanent magnet synchronous motor according to claim 2, characterized in that: When the auxiliary winding on the motor stator is connected to the power grid, the auxiliary winding generates a pole pair number of... The fundamental magnetic field, and the number of pole pairs is , The harmonic magnetic field, and , , The opposite magnetic fields rotate in the same direction.

4. A harmonic self-starting permanent magnet synchronous motor according to claim 3, characterized in that: The rotor is arranged with a set of pole pairs. Permanent magnets.

5. A harmonic self-starting permanent magnet synchronous motor according to claim 4, characterized in that: The motor starting winding generates The polar magnetic field generated by the auxiliary winding For polar magnetic fields, in phase difference Electrical angle refers to the spatially in-phase magnetic fields that are superimposed within the motor.

6. A harmonic self-starting permanent magnet synchronous motor according to claim 5, characterized in that: When the motor starting winding and auxiliary winding are simultaneously connected to the power grid, the combined spatial magnetic field generated by the starting winding and auxiliary winding is: Opposite magnetic field.

7. A harmonic self-starting permanent magnet synchronous motor according to claim 6, characterized in that: The motor is for For each pole, both sets of rotor windings have high winding coefficients, and when both sets of rotor windings are in the stator generation... In the polar magnetic field, both sets of rotor windings have strong electromagnetic coupling with the stator side.

8. A harmonic self-starting permanent magnet synchronous motor according to claim 7, characterized in that: The motor is for For each pole, the first rotor winding has a high winding coefficient, while the second rotor winding has a winding coefficient close to zero. When both sets of rotor windings are in the stator generation... In a polar magnetic field, the electromagnetic coupling between the first rotor winding and the stator side is strong, while the electromagnetic coupling between the second rotor winding and the stator side is weak, meaning that the second rotor winding is equivalent to a section of resistance.

9. A harmonic self-starting permanent magnet synchronous motor according to claim 8, characterized in that: The first rotor winding of the motor Phase 1 Side road, for Branch, and the second rotor winding's first Phase 1 Branch circuits are connected in parallel, when the two branches are generated by the stator. In a polar magnetic field, it is equivalent to The branch circuit is connected in series with a resistor.

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