CN216904479U

CN216904479U - EC motor

Info

Publication number: CN216904479U
Application number: CN202220167571.4U
Authority: CN
Inventors: 余海刚; 沙宇峰; 金海英
Original assignee: Chuangxin Electrical Motor Co ltd Shangyu Of Zhejiang
Current assignee: Chuangxin Electrical Motor Co ltd Shangyu Of Zhejiang
Priority date: 2022-01-21
Filing date: 2022-01-21
Publication date: 2022-07-05
Anticipated expiration: 2032-01-21

Abstract

The utility model discloses an EC motor, which can overcome the defect of fractional slot concentrated winding and ensure the improvement of the performance of the EC motor. The utility model adopts the design technology that the number of the stator slots is 3 times of the number of the poles of the motor, reduces the harmonic content and the harmonic intensity of the winding, reduces the loss, improves the efficiency and the power factor, reduces the heating, reduces the vibration and the noise of the motor, and greatly improves the speed regulation operation performance of the EC motor in the broadband range. Meanwhile, the stator punching sheet of the circular bottom groove type is adopted, the stator punching sheet has the advantages of long service life of the punching die and convenience in uniform distribution of magnetic flux density of iron core teeth and iron core yoke portions, the defect of fractional groove concentrated winding is overcome, and a solution scheme of designing a high-performance EC motor, which is simple, practical and strong in operability, is provided.

Description

EC motor

Technical Field

The utility model belongs to the technical field of motors, and particularly relates to an EC motor.

Background

An EC (Electrical Commutation) motor, which is a typical mechatronic product; an alternating current-to-direct current module is arranged in the driver, a direct current power supply is only the appearance of the EC motor, and the EC motor is an alternating current permanent magnet synchronous motor essentially. EC motor is actually just a BLDC (brushless direct current) motor of a different name, but why is the term added to a sufficiently complex motor type? One reason may be to avoid confusion among those familiar with ac motors, avoiding the association with any DC motor with a "brushed design" that has dominated the DC motor market for many years; the 'electronic commutation' is used instead of the 'brushless direct current', so that a user is not easy to confuse the design of a modern, high-efficiency and long-service-life motor with a brush motor, and the brush motor has the disadvantages of low efficiency, frequent maintenance and short service life.

Along with the development of ventilation technology, the requirements of intellectualization and energy conservation of the industrial air supply industry are higher and higher, the traditional AC motor is gradually replaced by an energy-saving, efficient and intelligent integrated EC motor along with the release of new energy efficiency requirements, products in the current foreign market are updated and upgraded, the propulsion speed is quite high, the domestic market is followed closely, the EC motor enters a major outbreak stage, the EC motor greatly replaces the AC motor to be applied, the market also provides more rigorous long-life requirements of 15 years and more, particularly in the industries such as subways, high-speed rails, tunnels, 5G data centers and the like, the service life is required to be more than 20 years, so the current conventional EC motor can not meet the requirements far, and the novel long-life EC motor is urgently needed by the market.

Therefore, the EC motor is a permanent magnet synchronous motor with a driver, and compared with the traditional AC motor, the EC motor, namely a three-phase alternating current permanent magnet synchronous motor, is more and more widely applied due to the advantages of energy conservation, high efficiency, intellectualization and the like. The EC motor mostly adopts fractional slot concentrated windings which are more and more widely applied because of the advantages of short end windings, compact structure and the like, but magnetomotive force harmonic waves generated by the concentrated windings are more complex and have large amplitude, and have adverse effects on the performance of the motor, the magnetomotive force harmonic waves increase the eddy current loss of magnetic steel, and the rotor is easy to cause heating and the permanent magnet is demagnetized.

Disclosure of Invention

In view of the above, the present invention provides an EC motor, which can overcome the defect of fractional slot concentrated winding and ensure the improvement of the performance of the EC motor.

The utility model provides an EC motor, includes controller, stator, rotor and end cover, and wherein the stator comprises frame and the stator core based on the round bottom groove, inlays in stator core's the groove and is equipped with the coil winding, and the rotor comprises pivot and the rotor core that is equipped with the magnet steel, and the end cover is connected respectively at frame both ends, and the controller input end connects three-phase alternating current power, and the controller output is connected to the coil winding in the stator core groove.

Furthermore, the stator core is formed by laminating stator punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm or 0.35 mm.

Furthermore, the coil windings in the stator core slots are 3-phase windings, the outgoing lines of the coil windings are 3, the stator punching sheets are equally split on the circumference of the inner diameter, the number of the stator slots is 3 times of the pole number of the motor, the harmonic content and the harmonic intensity of the windings can be reduced, the loss is reduced, the efficiency and the power factor are improved, the heat generation is reduced, the vibration and the noise of the motor are reduced, and the performance of speed regulation operation of the EC motor in a wide frequency range is greatly improved.

Furthermore, the groove type of the stator punching sheet is a round bottom groove, namely a pear-shaped groove, and compared with a flat bottom groove commonly adopted by fractional groove concentrated windings, the groove type has the advantages of long service life of a punching die and convenience for uniform distribution of magnetic flux density of iron core teeth and iron core yoke parts.

Furthermore, the rotor core is formed by laminating rotor punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm or 0.35 mm.

Furthermore, n magnetic steel grooves are formed in the rotor punching sheet, wherein n is 2 times, 3 times or 4 times of the number of pole pairs of the motor; when n is 2 times, 3 times or 4 times of the number of the pole pairs of the motor, the magnetic steel combinations of the rotor iron core are correspondingly V-shaped, U-shaped and W-shaped, the number of the magnetic steel combinations in the corresponding shapes is equal to the number of the pole pairs of the motor, and the magnetic steel combinations are uniformly distributed on the circumference of the rotor punching sheet. The magnetic steel combination has the advantages that: under the same physical size of the motor, the magnetic flux of each pole is increased, and the power factor, the efficiency and the power density of the motor can be improved; or the physical size of the motor can be minimized under the same output power of the motor.

The utility model adopts the design technology that the number of the stator slots is 3 times of the number of the poles of the motor, reduces the harmonic content and the harmonic intensity of the winding, reduces the loss, improves the efficiency and the power factor, reduces the heating, reduces the vibration and the noise of the motor, and greatly improves the speed regulation operation performance of the EC motor in the wide frequency range. Meanwhile, the stator punching sheet with the circular bottom groove type is adopted, so that the punching die has the advantages of long service life, convenience for uniform distribution of magnetic flux density of the iron core teeth and the iron core yoke parts, the defect of fractional groove concentrated winding is overcome, and a simple, practical and strong-operability solution for designing a high-performance EC motor is provided.

Drawings

Fig. 1(a) is a schematic diagram of a stator lamination commonly used for fractional-slot concentrated winding.

Fig. 1(b) is a schematic view of a flat-bottom slot of a stator lamination commonly used for fractional-slot concentrated winding.

Fig. 2(a) is a schematic view of a stator punching sheet according to the present invention.

Fig. 2(b) is a schematic view of a circular bottom groove of the stator punching sheet of the utility model.

Fig. 3 is a schematic wiring diagram of a stator winding of a conventional 12-slot 10-pole EC motor.

Fig. 4 is a schematic diagram of the stator winding wiring of a 30-slot 10-pole EC motor of the present invention.

FIG. 5 is a schematic view of a rotor punching sheet of a V-shaped magnetic steel slot.

FIG. 6 is a schematic view of a rotor punching sheet of a U-shaped magnetic steel slot.

FIG. 7 is a schematic view of a rotor punching sheet of a W-shaped magnetic steel slot.

Detailed Description

In order to more specifically describe the present invention, the following detailed description is provided for the technical solution of the present invention with reference to the accompanying drawings and the specific embodiments.

The EC motor comprises a controller, a stator, a rotor, end covers and the like, wherein the stator comprises a base and a stator core, a coil winding is embedded in a groove of the stator core, the rotor comprises a rotating shaft and a rotor core provided with magnetic steel, the end covers are respectively connected with two ends of the base, the input end of the controller is connected with a three-phase alternating current power supply, and the output end of the controller is connected to the coil winding of the stator core with the winding.

The core of the motor is a stator and a rotor, and the core of the stator is a punching sheet and a winding; in the EC motor, the groove type of the stator punching sheet is a round bottom groove, namely a pear-shaped groove, as shown in fig. 2 (b); compared with the flat-bottom slot shown in fig. 1(b) which is commonly used in fractional slot concentrated windings, the slot type has the advantages of long service life of a punching die and convenience in uniform distribution of magnetic flux density of the iron core teeth and the iron core yoke. The stator iron core is formed by laminating stator punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm (or 0.35mm), the coil winding is a 3-phase winding, and 3 outgoing lines are provided.

The stator punching sheet is equally divided into slots on the circumference of the inner diameter, and the number of the stator slots is equal to 3 times of the number of poles of the motor. For convenience of explanation, a 10-pole motor is taken as an example. Fig. 1(a) shows a 12-slot 10-pole stator lamination of the prior art, fig. 2(a) shows a stator lamination of the present invention, and the number of stator slots is 10 × 3 or 30.

The wiring of the 12-slot 10-pole stator winding in the prior art is shown in fig. 3, and is a concentrated winding with the span of 1, the number of coils of each motor is 12, and the problem that the fractional-slot concentrated winding is complex in harmonic wave and large in amplitude is inevitable. By harmonic analysis of the 12-slot 10-pole three-phase winding, it was found that: in the range of V1 to 55, in addition to the fundamental wave (V5), there are 18 kinds of harmonics such as 1, 7, 11, 13, 17, 19, 23, 29, 31, 35, 37, 41, 43, 47, 49, 53, 55, etc., and the harmonic intensity is up to 71.428571, which is very close to 100 of the fundamental wave, and the existence of such many harmonics will produce various adverse effects on the motor operation, for example: large vibration, electromagnetic noise, low efficiency, severe heat generation, etc.

The 30-slot 10-pole stator winding wiring of the utility model is a single-layer chain type winding with the span of 3 as shown in figure 4, and the number of coils of each motor is 15. By harmonic analysis of the 30-slot 10-pole three-phase winding, it was found that: in the range of V1 to 55, except for the fundamental wave (V5), only 3 kinds of harmonics, such as V25, 35, and 55, exist, and the harmonic intensity is 20 at the maximum, which is one fifth of the fundamental wave intensity. The utility model adopts the design technology that the number of the stator slots is 3 times of the number of the poles of the motor, reduces the harmonic content and the harmonic intensity of the winding, reduces the loss, improves the efficiency and the power factor, reduces the heating, reduces the vibration and the noise of the motor, and greatly improves the speed regulation operation performance of the EC motor in the wide frequency range.

Although the number (15) of 30-slot 10-pole coils is more than the number (12) of 12-slot 10-pole motor coils, the single-layer chain type winding structure is convenient for conventional wire inserting operation, flexible and convenient, and is particularly suitable for small-batch, multi-specification and customized production, so that the production efficiency is higher. In addition, compared with the 12-slot 10-pole motor manufacturing, the 30-slot 10-pole motor does not need to be additionally provided with expensive special winding equipment.

The rotor is also the core of the motor, the rotor core of the utility model is formed by laminating rotor punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm (or 0.35mm), n magnetic steel grooves are formed on the rotor punching sheets, n is equal to 2 times, 3 times or 4 times of the number of pole pairs of the motor and corresponds to the combination of V-shaped, U-shaped and W-shaped magnetic steels respectively, and the combination number of the V-shaped, U-shaped or W-shaped magnetic steels is equal to the number of the poles of the motor and the combination is uniformly distributed on the circumference of the rotor punching sheets. Fig. 5 shows an example of a 10-pole rotor sheet of the present invention, which has 20 magnetic steel slots, forming 10 groups of "V" shaped magnetic pole combinations; fig. 6 shows an example of a 6-pole rotor sheet of the present invention, which has 18 magnetic steel slots, forming 6 groups of "U" shaped magnetic pole combinations; fig. 7 shows an example of a 4-pole rotor sheet of the present invention, which has 16 magnetic steel slots, and forms 4 groups of W-shaped magnetic pole combinations. The magnetic steel combination has the advantages that: under the same physical size of the motor, the magnetic flux of each pole is increased, and the power factor, the efficiency and the power density of the motor can be improved; alternatively, the physical size of the motor can be minimized at the same output power of the motor.

The foregoing description of the embodiments is provided to enable one of ordinary skill in the art to make and use the utility model, and it is to be understood that other modifications of the embodiments, and the generic principles defined herein may be applied to other embodiments without the use of inventive faculty, as will be readily apparent to those skilled in the art. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications to the present invention based on the disclosure of the present invention within the protection scope of the present invention.

Claims

1. An EC motor, includes controller, stator, rotor and end cover, its characterized in that: the stator comprises a base and a stator core based on a circular bottom groove, a coil winding is embedded in the groove of the stator core, the rotor comprises a rotating shaft and a rotor core provided with magnetic steel, two ends of the base are respectively connected with an end cover, the input end of the controller is connected with a three-phase alternating current power supply, and the output end of the controller is connected to the coil winding in the groove of the stator core.

2. The EC motor of claim 1, wherein: the stator core is formed by laminating stator punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm or 0.35 mm.

3. The EC motor of claim 2, wherein: the coil winding in the stator core slot is 3 phase windings, the outgoing lines of the coil winding are 3, the stator punching sheet is equally divided into slots on the circumference of the inner diameter, and the number of the stator slots is 3 times of the number of poles of the motor.

4. The EC motor of claim 2, wherein: the groove type of the stator punching sheet is a round bottom groove.

5. The EC motor of claim 1, wherein: the rotor core is formed by laminating rotor punching sheets which are punched by high-quality cold-rolled electrical silicon steel sheets with the thickness of 0.5mm or 0.35 mm.

6. The EC motor of claim 5, wherein: n magnetic steel grooves are formed in the rotor punching sheet, wherein n is 2 times, 3 times or 4 times of the number of pole pairs of the motor; when n is 2 times, 3 times or 4 times of the number of the pole pairs of the motor, the magnetic steel combinations of the rotor iron core are correspondingly V-shaped, U-shaped and W-shaped, the number of the magnetic steel combinations in the corresponding shapes is equal to the number of the pole pairs of the motor, and the magnetic steel combinations are uniformly distributed on the circumference of the rotor punching sheet.